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Sample records for centre dot ccl4

  1. Ferroelectric phase transition in hydrogen-bonded 2-aminopyridine phosphate (NC sub 4 H sub 4 NH sub 2)centre dot H sub 3 PO sub 4

    CERN Document Server

    Czapla, Z; Waskowska, A

    2003-01-01

    A new crystal of 2-aminopyridine phosphate (NC sub 4 H sub 4 NH sub 2)centre dot H sub 3 PO sub 4 has been grown and its x-ray structure and physical properties were studied. At room temperature the crystals are monoclinic, space group C2/c. The flat 2-aminopyridine cations are hydrogen bonded to the anionic [PO sub 4 ] groups. The interesting feature of the crystal structure is the three-dimensional network of hydrogen bonds including, among others, two strong, symmetrical O centre dot centre dot centre dot H, H centre dot centre dot centre dot O interactions with disordered proton locations. Symmetrically related PO sub 4 anions linked through these protons form infinite (PO sub 4) subinfinity chains along the crystal a-axis. The anomalies in the temperature dependence of the electric permittivity showed that the crystal undergoes ferroelectric phase transition at T sub c = 103.5 K. The spontaneous polarization takes place along the crystal a-axis, being parallel to the chains of the hydrogen-bonded PO sub ...

  2. The Formation and Motion of CCl4- in CCl4 - Ar Mixture

    International Nuclear Information System (INIS)

    Martinez, H.; Yousif, F. B.

    2006-01-01

    This article deals with the measurement of the mobility of negative ions in the mixtures of CCl4 with Ar with the CCl4 ratio up to 33.3%. The Pulsed Townsend Technique was employed to produce an integrated ionic avalanches over a range of the density-reduced electric field E/N for which ionization is either negligible or absent, and attachment processes are dominant, leading to the formation of mostly CCl 4 - . The E/N range of measurement was 1 to 50 Td (1Td = 10-17 Vcm2). Our measurements strongly suggest that attachment is the dominant process and only negative ions are formed

  3. Higher expression of CCL2, CCL4, CCL5, CCL21, and CXCL8 chemokines in the skin associated with parasite density in canine visceral leishmaniasis.

    Directory of Open Access Journals (Sweden)

    Daniel Menezes-Souza

    Full Text Available BACKGROUND: The immune response in the skin of dogs infected with Leishmania infantum is poorly understood, and limited studies have described the immunopathological profile with regard to distinct levels of tissue parasitism and the clinical progression of canine visceral leishmaniasis (CVL. METHODOLOGY/PRINCIPAL FINDINGS: A detailed analysis of inflammatory cells (neutrophils, eosinophils, mast cells, lymphocytes, and macrophages as well as the expression of chemokines (CCL2, CCL4, CCL5, CCL13, CCL17, CCL21, CCL24, and CXCL8 was carried out in dermis skin samples from 35 dogs that were naturally infected with L. infantum. The analysis was based on real-time polymerase chain reaction (PCR in the context of skin parasitism and the clinical status of CVL. We demonstrated increased inflammatory infiltrate composed mainly of mononuclear cells in the skin of animals with severe forms of CVL and high parasite density. Analysis of the inflammatory cell profile of the skin revealed an increase in the number of macrophages and reductions in lymphocytes, eosinophils, and mast cells that correlated with clinical progression of the disease. Additionally, enhanced parasite density was correlated with an increase in macrophages and decreases in eosinophils and mast cells. The chemokine mRNA expression demonstrated that enhanced parasite density was positively correlated with the expression of CCL2, CCL4, CCL5, CCL21, and CXCL8. In contrast, there was a negative correlation between parasite density and CCL24 expression. CONCLUSIONS/SIGNIFICANCE: These findings represent an advance in the knowledge about skin inflammatory infiltrates in CVL and the systemic consequences. Additionally, the findings may contribute to the design of new and more efficient prophylactic tools and immunological therapies against CVL.

  4. Mineralization of CCl4 and CCl2F2 on solid surfaces

    International Nuclear Information System (INIS)

    Gaeb, S.; Schmitzer, J.; Turner, W.V.; Korte, F.; Technische Univ. Muenchen, Freising

    1980-01-01

    The mineralization of 14 CCl 4 and 14 CCl 2 F 2 in the dark is shown to be greatly dependent on the nature of the solid surfaces to which they are exposed, alumina being more effective than silica gel and a number of natural sands. Activation of the solids by drying or mechanically by tumbling leads to increased mineralization rates. (orig.)

  5. Hepatoprotective effect of basil ( Ocimum basilicum L.) on CCl 4 ...

    African Journals Online (AJOL)

    The hepatoprotective effect of basil (Ocimum basilicum) extract against liver fibrosis-induced by carbon tetrachloride (CCl4) was studied in rats. Rats were allocated into five groups: Group I (control group); Group II [CCl4 group; rats were injected subcutaneously with CCl4 (1 ml/kg b.w.) twice weekly for 4 weeks ...

  6. CCR4 agonists CCL22 and CCL17 are elevated in pediatric OMS sera: rapid and selective down-regulation of CCL22 by ACTH or corticosteroids.

    Science.gov (United States)

    Pranzatelli, Michael R; Tate, Elizabeth D; McGee, Nathan R; Colliver, Jerry A; Ransohoff, Richard M

    2013-05-01

    To study the role of Th2-attracting chemokines in opsoclonus-myoclonus syndrome (OMS), a serious neurological paraneoplastic disorder in need of better immunological understanding and therapy. The CCR4 agonists CCL22 and CCL17 were measured in serum by ELISA in children with OMS (238 and 260, respectively), pediatric controls (115 and 143), and other inflammatory neurological disorders (33 and 24). Both CCL22 (+55 %) and CCL17 (+121 %) were significantly elevated in untreated OMS compared to controls and inter-correlated (p OMS also were higher than in OIND (21 %, 41 %). The concentration of CCL22 in ACTH and steroids groups (not IVIg) was 51 % lower than in controls, but only a smaller effect of ACTH on CCL17 was found. Prospective longitudinal studies revealed a precipitous 81 % drop in CCL22 even by the first week of high-dose ACTH therapy, staying below control mean for at least 12 weeks, and a 34 % reduction after 8 months of combined treatment. Response to ACTH was dose-related (r = -0.50, p OMS. Marked and rapid reduction in CCL22, not CCL17, with either ACTH or steroid therapy suggests differential regulation and cellular sources of CCR4 ligands, and CCL22 as a potential candidate biomarker for ACTH or corticosteroid effect.

  7. CCl4 cirrhosis in rats

    DEFF Research Database (Denmark)

    Fischer-Nielsen, A; Poulsen, H E; Hansen, B A

    1991-01-01

    Cirrhosis of the rat liver was induced by a 12 week individualized CCl4/phenobarbital treatment. After treatment, all surviving animals (81%) showed cirrhosis of the liver. The cirrhosis induced was irreversible when evaluated 24 weeks after cessation of treatment. Quantitative liver function...

  8. Systemic levels of CCL2, CCL3, CCL4 and CXCL8 differ according to age, time period and season among children newly diagnosed with type 1 diabetes and their healthy siblings

    DEFF Research Database (Denmark)

    Thorsen, S U; Eising, S; Mortensen, H B

    2014-01-01

    The mechanisms by which antigen-specific T cells migrate to the islets of Langerhans in type 1 diabetes (T1D) are largely unknown. Chemokines attract immune cells to sites of inflammation. The aim was to elucidate the role of inflammatory chemokines in T1D at time of diagnosis. From a population......-based registry of children diagnosed with T1D from 1997 to 2005, we studied five different inflammatory chemokines (CCL2, CCL3, CCL4, CCL5 and CXCL8). Four hundred and eighty-two cases and 479 sibling frequencies matched on age and sample year distribution were included. Patients showed lower levels of CCL4...... compared to siblings, but this result was not significant after correction for multiple testing. CCL2, CCL3, CCL4 and CXCL8 levels were highest in the most recent cohorts (P

  9. Chlorination of uranium oxides with CCl4 using a mechanochemical method

    Science.gov (United States)

    Kitawaki, Shinichi; Nagai, Takayuki; Sato, Nobuaki

    2013-08-01

    A chlorination method for uranium oxides at low temperature was investigated by using a mechanochemical method. In particular, the possibility of the chlorination of uranium oxides, such as UO2 and U3O8, via mechanochemical reaction with CCl4 was studied using a planetary ball mill. Mechanochemical experiments were conducted to evaluate the effect of milling time, CCl4/uranium oxide molar ratio, and revolution speed on the reaction. The synthesized products were then subjected to X-ray diffraction analysis, and it was found that the chlorination of U3O8 with CCl4 to UOCl2, UCl4, and U2O2Cl5 proceeded. However, the chlorination reaction could not be observed when using UO2 powder as the raw material. The chlorination reaction could not be observed when using UO2 powder as the raw material. The chlorination of U3O8 with CCl4 to form UOCl2, UCl4, and U2O2Cl5 via mechanochemical reaction occurs at room temperature. The ratio of chlorination increases with milling time when the appropriate amount of CCl4 is employed. However, the use of excess liquid CCl4 decreases the mechanochemical effect.

  10. Solving the carbon tetrachloride (CCl4) budget mystery using surface observations

    Science.gov (United States)

    Liang, Q.; Newman, P. A.; Daniel, J. S.; Reimann, S.; Hall, B. D.; Dutton, G. S.; Kuijpers, L. J. M.

    2014-12-01

    Carbon tetrachloride (CCl4) is a major anthropogenic ozone-depleting substance, with an ozone depletion potential (with respect to CFC-11) of 0.82. CCl4 is also a greenhouse gas and the 100-yr global warming potential is 1,400. In 1987, the Montreal Protocol (MP) included CCl4, and production and consumption were phased out for developed countries in 1996. Developing countries were allowed a delayed reduction, but CCl4 was fully phased out from emissive uses in 2010. However, the near-zero 2007-2012 emissions estimate based on the UNEP reported production and feedstock usage cannot be reconciled with the observed slow decline of atmospheric concentrations, year-to-year variability, and the inter-hemispheric gradient (IHG). We use available source and sink data in the NASA 3-Dimensional (3-D) Chemistry Climate Model, GEOSCCM, to test existing emissions and lifetime estimates against CCl4 mixing ratio observations. Our model results show that the IHG and global trend provide useful information for quantitatively constraining CCl4 emissions and lifetime estimates. The observed IHG (1.5±0.2 ppt for 2000-2012) is primarily caused by ongoing current emissions, while ocean and soil losses and stratosphere-troposphere exchange together contribute a small negative gradient (~0 - -0.3 ppt). Using the observed CCl4 global trend and IHG from the National Oceanic and Atmospheric Administration - Global Monitoring Division (NOAA-GMD) and Advanced Global Atmospheric Gases Experiment (AGAGE) networks, we deduce the mean global emissions for the 2000-2012 period are 39 (34-45, lower-upper limit emission estimates) Gg/yr (~ 30% of the peak 1980s emissions) and a corresponding total lifetime of 35 (37-32, upper-lower limit lifetime estimates) years. These results point to the need for a more accurate bottom-up estimate of CCl4 emissions as well as re-evaluation of the CCl4 best estimate lifetime (currently 25 years).

  11. ideal hepatotoxicity model in rats using carbon tetrachloride (ccl4)

    African Journals Online (AJOL)

    DR. AMINU

    various concentrations of CCl4 had mean serum activities/ levels of AST, ... biological degenerative reaction, and may be an ... determine the dose range of the concentration of CCl4 ... total protein and albumin assessed by Biuret and BCG.

  12. Epstein-Barr virus EBNA2 directs doxorubicin resistance of B cell lymphoma through CCL3 and CCL4-mediated activation of NF-κB and Btk.

    Science.gov (United States)

    Kim, Joo Hyun; Kim, Won Seog; Hong, Jung Yong; Ryu, Kung Ju; Kim, Seok Jin; Park, Chaehwa

    2017-01-17

    Epstein-Barr virus (EBV)-encoded nuclear antigen, EBNA2, expressed in EBV-infected B lymphocytes is critical for lymphoblastoid cell growth. Microarray profiling and cytokine array screening revealed that EBNA2 is associated with upregulation of the chemokines CCL3 and CCL4 in lymphoma cells. Depletion or inactivation of CCL3 or CCL4 sensitized DLBCL cells to doxorubicin. Our results indicate that EBV influences cell survival via an autocrine mechanism whereby EBNA2 increases CCL3 and CCL4, which in turn activate the Btk and NF-κB pathways, contributing to doxorubicin resistance of B lymphoma cells. Western blot data further confirmed that CCL3 and CCL4 direct activation of Btk and NF-κB. Based on these findings, we propose that a pathway involving EBNA2/Btk/NF-κB/CCL3/CCL4 plays a key role in doxorubicin resistance, and therefore, inhibition of specific components of this pathway may sensitize lymphoma cells to doxorubicin. Evaluation of the relationship between CCL3 expression and EBV infection revealed high CCL3 levels in EBV-positive patients. Our data collectively suggest that doxorubicin treatment for EBNA2-positive DLBCL cells may be effectively complemented with a NF-κB or Btk inhibitor. Moreover, evaluation of the CCL3 and CCL4 levels may be helpful for selecting DLBCL patients likely to benefit from doxorubicin treatment in combination with the velcade or ibrutinib.

  13. Chlorination of uranium oxides with CCl4 using a mechanochemical method

    International Nuclear Information System (INIS)

    Kitawaki, Shinichi; Nagai, Takayuki; Sato, Nobuaki

    2013-01-01

    Highlights: • UCl 4 or UOCl 2 could be synthesized from U 3 O 8 with CCl 4 by using a planetary ball mill. • The chlorination could not be observed when using UO 2 powder as the starting material. • Extension of milling time was effective for chlorinating U 3 O 8 with the appropriate amount of CCl 4 . -- Abstract: A chlorination method for uranium oxides at low temperature was investigated by using a mechanochemical method. In particular, the possibility of the chlorination of uranium oxides, such as UO 2 and U 3 O 8 , via mechanochemical reaction with CCl 4 was studied using a planetary ball mill. Mechanochemical experiments were conducted to evaluate the effect of milling time, CCl 4 /uranium oxide molar ratio, and revolution speed on the reaction. The synthesized products were then subjected to X-ray diffraction analysis, and it was found that the chlorination of U 3 O 8 with CCl 4 to UOCl 2 , UCl 4 , and U 2 O 2 Cl 5 proceeded. However, the chlorination reaction could not be observed when using UO 2 powder as the raw material

  14. In vivo metabolism of CCl4 by gerbils pretreated with chlordecone, phenobarbital, or mirex

    International Nuclear Information System (INIS)

    Cai, Z.; Mehendale, H.M.

    1990-01-01

    Gerbils are known to be much more sensitive to CCl 4 lethality than rats as indicated by 48 hours LD 50 (0.08 vs 2.8 ml/kg). On the other hand, gerbils are refractory to chlordecone (CD) potentiation of CCl 4 toxicity. To investigate the possible mechanism underlying gerbil's high sensitivity to CCl 4 lethality, the authors studied in vivo metabolism of CCl 4 in gerbils pretreated with dietary CD (10 ppm), phenobarbital (PB, 225 ppm) or mirex (M, 10 ppm). The hepatic content of CCl 4 , the expiration of 14 CCl 4 and 14 CCl 4 -derived Co 2 , and lipid peroxidation were measured and the results were compared with our previous data for rats. After 15-day dietary pretreatment, male gerbils (60-80 g) received 14 CCl 4 (80 ml/kg; sp act: 0.04 mCi/mmol) ip in corn oil and the expired air was collected for 6 hours. More than 80% of the dose administered was expired as parent compound in 6 hours regardless of pretreatments. Expiration of 14 CCl 4 derived 14 CO 2 in control gerbils was 3.5-fold more than in control rats and was increased significantly in pretreated gerbils (M>PB>CD). PB and M pretreatments resulted in significant increase of 14 C label bound to non-lipid fraction of hepatic content as compared with CD or control gerbils. The radiolabel present in hepatic content of control gerbils was 5-fold higher than that of control rats. In vivo liquid peroxidation measured as diene conjugation in lipid extracts from the livers was lower in gerbils than in rats, and there were no significant differences among control and pretreated gerbils. These data indicate that the more extensive metabolism of CCl 4 in gerbils may partially explain their high sensitivity to CCl 4 toxicity. However, the significantly enhanced metabolism of CCl 4 found in CD, PB, or M pretreated gerbils did not lead to amplification of CCl 4 hepatotoxic and lethal effects

  15. Role of suppressed hepatocellular regeneration and Ca2+ in chlordecone-potentiated CCl4 hepatotoxicity

    International Nuclear Information System (INIS)

    Bell, A.N.

    1987-01-01

    The mechanism by which the chlorinated pesticide chlordecone (CD; Kepone) potentiates CCl 4 -induced hepatotoxicity and lethality was investigated. It was hypothesized that perturbations in Ca 2+ homeostasis, greater than those observed with a low dose of CCl 4 alone, in concert with a suppression of hepatocellular regeneration induced by CD alone or by CD + CCl 4 are responsible, at least in part, for CD-potentiated CCl 4 hepatotoxicity. Ca 2+ homeostasis was evaluated by measuring total cell Ca 2+ and 45 Ca 2+ uptake in viable isolated hepatocyte suspension obtained from normal and CD-pretreated rats receiving CCl 4 in vivo. In the normal rats in vivo CCL challenge did not affect 45 Ca 2+ uptake by viable isolated hepatocytes. In contrast, 45 Ca 2+ uptake was inhibited in viable isolated hepatocytes obtained from rats exposed to CD + CCl 4

  16. CCl 4 chemistry on the magnetite selvedge of single-crystal hematite: competitive surface reactions

    Science.gov (United States)

    Adib, K.; Camillone, N., III; Fitts, J. P.; Rim, K. T.; Flynn, G. W.; Joyce, S. A.; Osgood, R. M., Jr.

    2002-01-01

    Temperature programmed reaction/desorption (TPR/D) studies were undertaken to characterize the surface chemistry which occurs between CCl 4 and the Fe 3O 4 (1 1 1) selvedge of single crystal α-Fe 2O 3 (0 0 0 1). Six separate desorption events are clearly observed and four desorbing species are identified: CCl 4, OCCl 2, C 2Cl 4 and FeCl 2. It is proposed that OCCl 2, CCl 4 and C 2Cl 4 are produced in reactions involving the same precursor, CCl 2. Three reaction paths compete for the CCl 2 precursor: oxygen atom abstraction (for OCCl 2), molecular recombinative desorption (for CCl 4) and associative desorption (for C 2Cl 4). During the TPR/D temperature ramp, the branching ratio is observed to depend upon temperature and the availability of reactive sites. The data are consistent with a rich site-dependent chemistry.

  17. A study of the x-irradiated Cs sub 5 H sub 3 (SO sub 4) sub 4 centre dot H sub 2 O crystal by EPR in the 80-415 K temperature range

    CERN Document Server

    Waplak, S; Baranov, A I; Shuvalov, L A

    1997-01-01

    The EPR spectra of the x-irradiated fast proton conductor Cs sub 5 H sub 3 (SO sub 4) sub 4 centre dot H sub 2 O were investigated in the temperature range of 80-415 K. Two kinds of paramagnetic SO sub 4 sup - centres with different proton configurations below about 370 K and freeze-out behaviour of one of them below about 200 K were observed. The role of acid proton dynamics with respect to the glassy-like transition is discussed. (author)

  18. Hepatoprotective effects of Portulaca oleracea extract against CCl4-induced damage in rats.

    Science.gov (United States)

    Eidi, Akram; Mortazavi, Pejman; Moghadam, Jalal Zarringhalam; Mardani, Parisa Mousavi

    2015-07-01

    Purslane (Portulaca oleracea L., Portulacaceae) has been traditionally used in folk medicine to afford protection against liver injury, although its actual efficacy remains uncertain. To evaluate purslane as a hepatoprotective agent, we investigated the protective effect of its ethanol extract against carbon tetrachloride (CCl4)-induced hepatic toxicity in rats. A total of 108 male Wistar rats were randomly divided into 12 groups. The first group was maintained as normal control, whereas CCl4 (0.5 ml/kg bw, 50% CCl4 in olive oil, i.p.), purslane extract (0.005, 0.01, 0.05, 0.1, and 0.15 g/kg bw, intragastrically), and purslane extract (five doses as above) along with CCl4 were administered to the Groups II, III-VII, and VIII-XII, respectively. The rats were sacrificed on the 30th day, and blood was withdrawn by cardiac puncture. Liver damage was assessed by measuring hepatic marker enzymes (ALT, AST, ALP, GGT, and SOD) and histopathological observation. Treatment with CCl4 resulted in increased serum activities of marker enzymes with a concomitant decrease in SOD. Histological alterations were also observed in the liver tissue upon CCl4 treatment. Administration of purslane extract (0.01, 0.05, 0.1, and 0.15 g/kg b.w.) significantly showed a marked tendency towards normalization of all measured biochemical parameters in CCl4-treated rats. Histopathological changes also paralleled the detected alteration in markers of liver function. These results demonstrate that purslane exerts protective effects against CCl4-induced damage in rat liver and supports a potential therapeutic use of purslane as an alternative for patients with liver diseases.

  19. Chlorination of uranium oxides with CCl{sub 4} using a mechanochemical method

    Energy Technology Data Exchange (ETDEWEB)

    Kitawaki, Shinichi, E-mail: kitawaki.shinichi@jaea.go.jp [Nuclear Fuel Cycle Engineering Laboratories, Japan Atomic Energy Agency, 4-33 Muramatsu, Tokai, Naka, Ibaraki 319-1194 (Japan); Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba, Sendai, Miyagi 980-8577 (Japan); Nagai, Takayuki [Nuclear Fuel Cycle Engineering Laboratories, Japan Atomic Energy Agency, 4-33 Muramatsu, Tokai, Naka, Ibaraki 319-1194 (Japan); Sato, Nobuaki [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba, Sendai, Miyagi 980-8577 (Japan)

    2013-08-15

    Highlights: • UCl{sub 4} or UOCl{sub 2} could be synthesized from U{sub 3}O{sub 8} with CCl{sub 4} by using a planetary ball mill. • The chlorination could not be observed when using UO{sub 2} powder as the starting material. • Extension of milling time was effective for chlorinating U{sub 3}O{sub 8} with the appropriate amount of CCl{sub 4}. -- Abstract: A chlorination method for uranium oxides at low temperature was investigated by using a mechanochemical method. In particular, the possibility of the chlorination of uranium oxides, such as UO{sub 2} and U{sub 3}O{sub 8}, via mechanochemical reaction with CCl{sub 4} was studied using a planetary ball mill. Mechanochemical experiments were conducted to evaluate the effect of milling time, CCl{sub 4}/uranium oxide molar ratio, and revolution speed on the reaction. The synthesized products were then subjected to X-ray diffraction analysis, and it was found that the chlorination of U{sub 3}O{sub 8} with CCl{sub 4} to UOCl{sub 2}, UCl{sub 4}, and U{sub 2}O{sub 2}Cl{sub 5} proceeded. However, the chlorination reaction could not be observed when using UO{sub 2} powder as the raw material.

  20. In vivo metabolism of CCl4 by rats pretreated with chlordecone, mirex, or phenobarbital

    International Nuclear Information System (INIS)

    Mehendale, H.M.; Klingensmith, J.S.

    1988-01-01

    The propensity of chlordecone (CD) to potentiate hepatotoxic and lethal effects of CCl4 is well established. Mirex (M), a close structural analogue of CD, or phenobarbital (PB), powerful inducers of hepatic microsomal drug metabolizing enzymes, are much weaker potentiators of CCl4 toxicity. The purpose of this study was to test the possibility that CD potentiates the toxicity of CCl4 by increasing the metabolism of CCl4 to a greater degree than either PB or M. We compared the in vivo metabolism of CCl4 in rats pretreated with CD, M, or PB, by measuring the hepatic content of 14CCl4, the expiration of 14CCl4, expiration of 14CCl4-derived 14CO2, and lipid peroxidation. Male Sprague-Dawley rats (250-270 g) were pretreated with a single oral dose of CD (10 mg/kg), M (10 mg/kg), or corn oil vehicle (1 ml/kg). PB pretreatment consisted of an ip injection of sodium PB (80 mg/kg) in saline (0.9%) for 2 successive days. Twenty-four hours later, 14CCl4 (0.1 ml/kg; sp act: 0.04 mCi/mmol) was administered ip in corn oil and the radioactivity present in the expired air was collected for 6 hr. Excretion of the parent compound as represented by the 14C label in the toluene trap was unchanged by any of the pretreatments. Expiration of 14CO2 measured during the 6 hr after CCl4 administration was increased in animals pretreated with PB or CD. In vivo lipid peroxidation measured as diene conjugation in lipids extracted from the livers was increased to a similar extent in animals pretreated with PB and CD, whereas the serum transaminases (ALT, AST) were significantly elevated only in animals pretreated with CD.M did not affect 14CO2 production and was without a significant effect on the lipid peroxidation

  1. Prevention of CCl4 induced hypogonadism with Raphanus sativus seeds in rat.

    Science.gov (United States)

    Tabassum, Farhana; Khan, Muhammad Rashid

    2017-03-01

    Raphanus sativus seeds are used as condiment and to treat hypogonadism, various ailments of liver and kidneys. The aim of this study was to evaluate the potential protective effects of methanol extract of R. sativus seeds (RSME) against hypogonadism induced with carbon tetrachloride (CCl 4 ) in Sprague-Dawley male rats. Thirty six rats were divided in to six groups with six animals in each. Animals of Group I were control and treated with saline, Group II, III and IV were given orally CCl 4 (1 ml/kg bw; 10% in corn oil). Rats of Group III and IV were also simultaneously given RSME at 100 mg/kg bw and 200 mg/kg bw respectively. However, Group V and VI received RSME (100; 200 mg/kg bw, respectively) alone. All treatments were given at alternate days for 15 days. Treatment of CCl4 to rats decreased (P < 0.001) the level of CAT, POD, SOD, GST, GSH-Px and GSR antioxidant enzymes in testes of rat. Concentration of lipid peroxides (TBARS) was increased (P < 0.001) whereas concentration of GSH was decreased (P < 0.001) in testes of CCl4 treated animals. Concentration of testosterone, FSH and LH in serum was decreased (P < 0.001) while the level of estradiol and prolactin was increased (P < 0.001) in CCl4 treated rats. Injuries in seminiferous tubules were determined in histopathology of testes. Administration of RSME, dose dependently, markedly ameliorated the oxidative stress of CCl4 thereby restoring the level of antioxidant enzymes, lipid peroxides, reduced glutathione, male hormones and alterations in histopathology.

  2. Experimental determination of CCl4 hydrate phase equlibria up to high pressures

    NARCIS (Netherlands)

    Shariati - Sarabi, A.; Lameris, G.H.; Peters, C.J.

    2015-01-01

    A number of hydrate phase boundaries of the binary system of tetrachloromethane (CCl4) + water were measured experimentally at several temperatures and from low pressures up to 89.25 MPa. These hydrate phase boundaries included hydrate–ice–vapor, hydrate–liquid CCl4–vapor, hydrate–water–vapor,

  3. Current sources of carbon tetrachloride (CCl4) in our atmosphere

    Science.gov (United States)

    Sherry, David; McCulloch, Archie; Liang, Qing; Reimann, Stefan; Newman, Paul A.

    2018-02-01

    Carbon tetrachloride (CCl4 or CTC) is an ozone-depleting substance whose emissive uses are controlled and practically banned by the Montreal Protocol (MP). Nevertheless, previous work estimated ongoing emissions of 35 Gg year-1 of CCl4 into the atmosphere from observation-based methods, in stark contrast to emissions estimates of 3 (0-8) Gg year-1 from reported numbers to UNEP under the MP. Here we combine information on sources from industrial production processes and legacy emissions from contaminated sites to provide an updated bottom-up estimate on current CTC global emissions of 15-25 Gg year-1. We now propose 13 Gg year-1 of global emissions from unreported non-feedstock emissions from chloromethane and perchloroethylene plants as the most significant CCl4 source. Additionally, 2 Gg year-1 are estimated as fugitive emissions from the usage of CTC as feedstock and possibly up to 10 Gg year-1 from legacy emissions and chlor-alkali plants.

  4. Herbal Supplement Ameliorates Cardiac Hypertrophy in Rats with CCl4-Induced Liver Cirrhosis

    Directory of Open Access Journals (Sweden)

    Ping-Chun Li

    2012-01-01

    Full Text Available We used the carbon tetrachloride (CCl4 induced liver cirrhosis model to test the molecular mechanism of action involved in cirrhosis-associated cardiac hypertrophy and the effectiveness of Ocimum gratissimum extract (OGE and silymarin against cardiac hypertrophy. We treated male wistar rats with CCl4 and either OGE (0.02 g/kg B.W. or 0.04 g/kg B.W. or silymarin (0.2 g/kg B.W.. Cardiac eccentric hypertrophy was induced by CCl4 along with cirrhosis and increased expression of cardiac hypertrophy related genes NFAT, TAGA4, and NBP, and the interleukin-6 (IL-6 signaling pathway related genes MEK5, ERK5, JAK, and STAT3. OGE or silymarin co-treatment attenuated CCl4-induced cardiac abnormalities, and lowered expression of genes which were elevated by this hepatotoxin. Our results suggest that the IL-6 signaling pathway may be related to CCl4-induced cardiac hypertrophy. OGE and silymarin were able to lower liver fibrosis, which reduces the chance of cardiac hypertrophy perhaps by lowering the expressions of IL-6 signaling pathway related genes. We conclude that treatment of cirrhosis using herbal supplements is a viable option for protecting cardiac tissues against cirrhosis-related cardiac hypertrophy.

  5. Flat-topped emission centred at 1 250 nm from quantum dot superluminescent diodes

    Directory of Open Access Journals (Sweden)

    R.A. Hogg

    2010-01-01

    Full Text Available We present a method for tailoring a broadband and flat-topped emission spectrum in quantum dot superluminescent diodes based upon modification of the dots-in-compositionally-modulated-well (DCMWELL technique. We demonstrate flat-topped emission with 95 nm full width at half maximum (FWHM, centred at 1 250 nm, and with output power in excess of 8 mW.

  6. Ferroelectric TGS ((NH sub 2 CH sub 2 COOH) sub 3 centre dot H sub 2 SO sub 4) under high pressure

    CERN Document Server

    Kobayashi, Y; Furuta, H; Endo, S; Deguchi, K

    2002-01-01

    The ferroelectric transition temperature T sub c of (NH sub 2 CH sub 2 COOH) sub 3 centre dot H sub 2 SO sub 4 (TGS), which is a typical order-disorder-type ferroelectric, was determined by dielectric constant and Raman scattering measurements under high pressure. T sub c increased, passed through a maximum and then decreased slightly with increasing pressure, and then abruptly dropped at about 2.5 GPa, where a transition to a new high-pressure phase was confirmed to exist. A tentative p-T phase diagram was proposed for TGS.

  7. The essential oil of Artemisia capillaris protects against CCl4-induced liver injury in vivo

    Directory of Open Access Journals (Sweden)

    Qinghan Gao

    Full Text Available Abstract To study the hepatoprotective effect of the essential oil of Artemisia capillaris Thunb., Asteraceae, on CCl4-induced liver injury in mice, the levels of serum aspartate aminotransferase and alanine aminotransferase, hepatic levels of reduced glutathione, activity of glutathione peroxidase, and the activities of superoxide dismutase and malondialdehyde were assayed. Administration of the essential oil of A. capillaris at 100 and 50 mg/kg to mice prior to CCl4 injection was shown to confer stronger in vivo protective effects and could observably antagonize the CCl4-induced increase in the serum alanine aminotransferase and aspartate aminotransferase activities and malondialdehyde levels as well as prevent CCl4-induced decrease in the antioxidant superoxide dismutase activity, glutathione level and glutathione peroxidase activity (p < 0.01. The oil mainly contained β-citronellol, 1,8-cineole, camphor, linalool, α-pinene, β-pinene, thymol and myrcene. This finding demonstrates that the essential oil of A. capillaris can protect hepatic function against CCl4-induced liver injury in mice.

  8. MIPAS IMK/IAA carbon tetrachloride (CCl4) retrieval and first comparison with other instruments

    Science.gov (United States)

    Eckert, Ellen; von Clarmann, Thomas; Laeng, Alexandra; Stiller, Gabriele P.; Funke, Bernd; Glatthor, Norbert; Grabowski, Udo; Kellmann, Sylvia; Kiefer, Michael; Linden, Andrea; Babenhauserheide, Arne; Wetzel, Gerald; Boone, Christopher; Engel, Andreas; Harrison, Jeremy J.; Sheese, Patrick E.; Walker, Kaley A.; Bernath, Peter F.

    2017-07-01

    MIPAS thermal limb emission measurements were used to derive vertically resolved profiles of carbon tetrachloride (CCl4). Level-1b data versions MIPAS/5.02 to MIPAS/5.06 were converted into volume mixing ratio profiles using the level-2 processor developed at Karlsruhe Institute of Technology (KIT) Institute of Meteorology and Climate Research (IMK) and Consejo Superior de Investigaciones Científicas (CSIC), Instituto de Astrofísica de Andalucía (IAA). Consideration of peroxyacetyl nitrate (PAN) as an interfering species, which is jointly retrieved, and CO2 line mixing is crucial for reliable retrievals. Parts of the CO2 Q-branch region that overlap with the CCl4 signature were omitted, since large residuals were still found even though line mixing was considered in the forward model. However, the omitted spectral region could be narrowed noticeably when line mixing was accounted for. A new CCl4 spectroscopic data set leads to slightly smaller CCl4 volume mixing ratios. In general, latitude-altitude cross sections show the expected CCl4 features with highest values of around 90 pptv at altitudes at and below the tropical tropopause and values decreasing with altitude and latitude due to stratospheric decomposition. Other patterns, such as subsidence in the polar vortex during winter and early spring, are also visible in the distributions. The decline in CCl4 abundance during the MIPAS Envisat measurement period (July 2002 to April 2012) is clearly reflected in the altitude-latitude cross section of trends estimated from the entire retrieved data set.

  9. MIPAS IMK/IAA carbon tetrachloride (CCl4 retrieval and first comparison with other instruments

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    E. Eckert

    2017-07-01

    Full Text Available MIPAS thermal limb emission measurements were used to derive vertically resolved profiles of carbon tetrachloride (CCl4. Level-1b data versions MIPAS/5.02 to MIPAS/5.06 were converted into volume mixing ratio profiles using the level-2 processor developed at Karlsruhe Institute of Technology (KIT Institute of Meteorology and Climate Research (IMK and Consejo Superior de Investigaciones Científicas (CSIC, Instituto de Astrofísica de Andalucía (IAA. Consideration of peroxyacetyl nitrate (PAN as an interfering species, which is jointly retrieved, and CO2 line mixing is crucial for reliable retrievals. Parts of the CO2 Q-branch region that overlap with the CCl4 signature were omitted, since large residuals were still found even though line mixing was considered in the forward model. However, the omitted spectral region could be narrowed noticeably when line mixing was accounted for. A new CCl4 spectroscopic data set leads to slightly smaller CCl4 volume mixing ratios. In general, latitude–altitude cross sections show the expected CCl4 features with highest values of around 90 pptv at altitudes at and below the tropical tropopause and values decreasing with altitude and latitude due to stratospheric decomposition. Other patterns, such as subsidence in the polar vortex during winter and early spring, are also visible in the distributions. The decline in CCl4 abundance during the MIPAS Envisat measurement period (July 2002 to April 2012 is clearly reflected in the altitude–latitude cross section of trends estimated from the entire retrieved data set.

  10. A novel role of Yin-Yang-1 in pulmonary tuberculosis through the regulation of the chemokine CCL4.

    Science.gov (United States)

    Rangel-Santiago, Jesus F; Baay-Guzman, Guillermina J; Duran-Padilla, Marco A; Lopez-Bochm, Karla A; Garcia-Romero, Beatriz L; Hernandez-Cueto, Daniel D; Pantoja-Escobar, Gerardo; Vega, Mario I; Hernandez-Pando, Rogelio; Huerta-Yepez, Sara

    2016-01-01

    Mycobacterium tuberculosis (M. tb) is the etiological agent of pulmonary tuberculosis (TB); this disease remains a worldwide health problem. Yin-Yang-1 (YY1) plays a major role in the maintenance and progression of some pulmonary diseases, including pulmonary fibrosis. However, the role of YY1 in TB remains unknown. The aim of this study was to elucidate the role of YY1 in the regulation of CCL4 and its implication in TB. We determined whether YY1 regulates CCL4 using reporter plasmids, ChIP and siRNA assays. Immunohistochemistry and digital pathology were used to measure the expression of YY1 and CCL4 in a mouse model of TB. A retrospective comparison of patients with TB and control subjects was used to measure the expression of YY1 and CCL4 using tissue microarrays. Our results showed that YY1 regulates the transcription of CCL4; moreover, YY1, CCL4 and TGF-β were overexpressed in the lung tissues of mice with TB during the late stages of the disease and the tissues of TB patients. The expression of CCL4 and TGF-β correlated with YY1 expression. In conclusion, YY1 regulates CCL4 transcription; moreover, YY1 is overexpressed in experimental and human TB and is positively correlated with CCL4 and TGF-β expression. Therefore, treatments that decrease YY1 expression may be a new therapeutic strategy against TB. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Antifibrotic effects of D-limonene (5(1-methyl-4-[1-methylethenyl]) cyclohexane) in CCl4 induced liver toxicity in Wistar rats.

    Science.gov (United States)

    Ahmad, Sheikh Bilal; Rehman, Muneeb U; Fatima, Bilques; Ahmad, Bilal; Hussain, Ishraq; Ahmad, Sheikh Pervaiz; Farooq, Adil; Muzamil, Showkeen; Razzaq, Rahil; Rashid, Shahzada Mudasir; Ahmad Bhat, Showkat; Mir, Manzoor Ur Rahman

    2018-03-01

    This study was designed to assess the potential antifibrotic effect of D-Limonene-a component of volatile oils extracted from citrus plants. D-limonene is reported to have numerous therapeutic properties. CCl 4 -intduced model of liver fibrosis in Wistar rats is most widely used model to study chemopreventive studies. CCl 4 -intoxication significantly increased serum aminotransferases and total cholesterol these effects were prevented by cotreatment with D-Limonene. Also, CCl 4 -intoxication caused depletion of glutathione and other antioxidant enzymes while D-Limonene preserved them within normal values. Hydroxyproline and malondialdehyde content was increased markedly by CCl 4 treatment while D-Limonene prevented these alterations. Levels of TNF-α, TGF-β, and α-SMA were also assessed; CCl 4 increased the expression of α-SMA, NF-κB and other downstream inflammatory cascade while D-Limonene co-treatment inhibited them. Collectively these findings indicate that D-Limonene possesses potent antifibrotic effect which may be attributed to its antioxidant and anti-inflammatory properties. © 2017 Wiley Periodicals, Inc.

  12. Antioxidant activity of the oyster mushroom, Pleurotus ostreatus, on CCl(4)-induced liver injury in rats.

    Science.gov (United States)

    Jayakumar, T; Ramesh, E; Geraldine, P

    2006-12-01

    This study was undertaken to investigate the putative antioxidant activity of the oyster mushroom Pleurotus ostreatus on CCl(4)-induced liver damage in male Wistar rats. Intraperitoneal administration of CCl(4) (2ml/kg) to rats for 4 days resulted in significantly elevated (pSALP) compared to controls. In the liver, significantly elevated levels (pSALP levels reverted to near normal, while the hepatic concentration of GSH, CAT, SOD and Gpx were significantly increased (p<0.05) and that of MDA significantly (p<0.05) lowered, when compared to CCl(4)-exposed untreated rats. Histopathological studies confirmed the hepatoprotective effect conferred by the extract of P. ostreatus. These results suggest that an extract of P. ostreatus is able to significantly alleviate the hepatotoxicity induced by CCl(4) in the rat.

  13. The Protective Effect of Liquorice Plant Extract on CCl4-Induced Hepatotoxicity in Common Carp (Cyprinus carpio

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    Hassan Malekinejad

    2010-12-01

    Full Text Available The protective effect of liquorice plant extract (LPE on CCl4-induced hepatotoxicity in common carp was evaluated using fifty adult carps. The fish were cultured in a standard environment in terms of water flow rate, oxygen, pH, food and temperature. The fish were assigned into 5 groups (N = 10 as control, sham, and tests. The test groups were pre-treated for 3 h with various concentrations of LPE, 3 days before CCl4 exposure. The control and sham groups received normal saline before and after CCl4 exposure. To induce hepatotoxicity, animals in the sham and test groups were exposed against 100 l L-1 CCl4 for 45 min. The fish in all groups 1 h after CCl4 exposure were anesthetized and the blood samples were collected. Immediately the liver specimens were dissected out and were stored in 10 % formalin for further pathological studies. Determination of serum level of ALP and SGOT revealed that acute form of CCl4 exposure elevated significantly (P < 0.05 the serum level of either tested hepatic marker enzymes. While 3 days pretreatment with LPE prevented from ALP and SGOT enhancement. The pathological evaluation revealed that the CCl4 exposure resulted in a minor pathologic manifestation such as slight congestion, which the LPE pretreated groups showed the remarkable improvement. The anti-oxidant capacity of LPE was assayed by FRAP and DPPH methods. Both provided techniques showed that LPE exerts an excellent anti-oxidant effect. This data suggest that LPE exerts protective effect against CCl4-induced hepatotoxicity. Moreover, the hepatoprotective effect of LPE may attribute to its antioxidant capacity.

  14. Prevention of carbon tetrachloride (CCl4)-induced toxicity in testes of rats treated with Physalis peruviana L. fruit.

    Science.gov (United States)

    Abdel Moneim, Ahmed E

    2016-06-01

    Treatment of rats with carbon tetrachloride (CCl4; 2 ml/kg body weight) once a week for 12 weeks caused a significant decrease in serum levels of testosterone, luteinizing hormone, and follicle-stimulating hormone. These decreases in sex hormones were reduced with Physalis peruviana L. (Cape gooseberry) juice supplementation. In addition, testicular activity of antioxidant enzymes such as superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glutathione-S-transferase suppressed with CCl4 were elevated after P. peruviana juice supplements. P. peruviana juice supplementation significantly increased the testicular glutathione and significantly decreased the level of lipid peroxidation and the nitric oxide production compared with the CCl4 group. In addition, the decline in the activity of antioxidant enzymes after CCl4 was ameliorated by P. peruviana Moreover, degeneration of germ and Leydig cells along with deformities in spermatogenesis induced after CCl4 injections were prevented with the supplementation of P. peruviana juice. Furthermore, P. peruviana juice attenuated CCl4-induced apoptosis in testes tissue by inhibition of caspase-3 activity. The results clearly demonstrate that P. peruviana juice augments the antioxidants defense mechanism against CCl4-induced reproductive toxicity and provides evidence that the juice may have a therapeutic role in free radical-mediated diseases and infertility. © The Author(s) 2014.

  15. Hepatoprotective effect of methanolic Tanacetum parthenium extract on CCl4-induced liver damage in rats

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    Yavar Mahmoodzadeh

    Full Text Available The purpose of this study was to investigate the effects of Tanacetum Parthenium Extract (TPE on Lipid peroxidation, antioxidant enzymes, biochemical factors, and liver enzymes in the rats damaged by Carbon Tetrachloride (CCl4.54 male Wistar rats were divided into 9 groups each consisting of 6 rats. Two of the groups were control groups (normal and damage control groups, 4 of them were exposure groups which were respectively administered with 40, 80, and 120 mg/kg of TPE and silymarin for 14 days before being damaged by CCl4, and the other 3 groups were post-treatment groups which received 80 and 120 mg/kg of TPE and silymarin 2, 6, 24, and 48 h after being injected with CCl4. At the end of the study, biochemical factors, serum liver enzymes, malondialdehyde level, antioxidant enzymes, and liver morphology were assayed.Pre- and post-treatment with TPE could significantly decrease ALT, AST, ALP, TG, LDL, TC, and glucose levels and increase HDL, and albumin levels and catalase, SOD, and GPx activities compared to the CCl4-damaged control group.The results of this study are indicative of the antioxidant activity of TPE, its potential hepatoprotective effects, and its probable therapeutic properties for laboratory animals damaged by CCl4. Keywords: Tanacetum parthenium, Carbon tetrachloride, Oxidative stress, Antioxidant enzymes, Liver damage

  16. Hepatoprotective effect of Opuntia dillenii seed oil on CCl4 induced acute liver damage in rat

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    Mohamed Bouhrim

    2018-01-01

    Full Text Available Objective: To investigate the hepatoprotective effect of Opuntia dillenii seed oil (ODSO on CCl4 provoked liver injury in rat. Methods: Animals were treated orally with ODSO at a concentration of 2 mL/kg, once daily for one week before the first intraperitoneal injection of CCl4, and thereafter the administration of the oil was continued for 7 days until the introduction of the second injection of CCl4. Fourteen hours after the last dose of CCl4, rats were sacrificed, and the relative liver weight, weight gain, alkaline phosphatase, aspartate amino transferase, alanine aminotransferase, direct bilirubin, total bilirubin, triglycerides, total cholesterol, very low density lipoprotein, low density lipoprotein, high density lipoprotein, plasmatic glucose, urea, creatinine, acid uric and malondialdehyde were determined. Results: The significant increase was found in relative liver weight and plasma levels of alanine aminotransferase, aspartate amino transferase, alkaline phosphatase, total bilirubin, direct bilirubin, triglycerides, very low-density lipoprotein, urea, uric acid and malondialdehyde. Likewise, the significant decrease was indicated in the weight gain and the level of glucose plasmatic, and high-density lipoprotein levels in CCl4 produced liver injury in rats were re-established to normal levels when treated with ODSO. While, no change was observed in the total cholesterol, low-density lipoprotein and creatinine in all animals. Conclusions: We conclude that the ODSO has a protective effect on CCl4-mediated liver injury. Hence, we suggest its inclusion as a preventive control of liver disorders.

  17. CCl4 distribution derived from MIPAS ESA v7 data: intercomparisons, trend, and lifetime estimation

    Science.gov (United States)

    Valeri, Massimo; Barbara, Flavio; Boone, Chris; Ceccherini, Simone; Gai, Marco; Maucher, Guido; Raspollini, Piera; Ridolfi, Marco; Sgheri, Luca; Wetzel, Gerald; Zoppetti, Nicola

    2017-08-01

    Atmospheric emissions of carbon tetrachloride (CCl4) are regulated by the Montreal Protocol due to its role as a strong ozone-depleting substance. The molecule has been the subject of recent increased interest as a consequence of the so-called mystery of CCl4, the discrepancy between atmospheric observations and reported production and consumption. Surface measurements of CCl4 atmospheric concentrations have declined at a rate almost 3 times lower than its lifetime-limited rate, suggesting persistent atmospheric emissions despite the ban. In this paper, we study CCl4 vertical and zonal distributions in the upper troposphere and lower stratosphere (including the photolytic loss region, 70-20 hPa), its trend, and its stratospheric lifetime using measurements from the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS), which operated onboard the ENVISAT satellite from 2002 to 2012. Specifically, we use the MIPAS data product generated with Version 7 of the Level 2 algorithm operated by the European Space Agency.The CCl4 zonal means show features typical of long-lived species of anthropogenic origin that are destroyed primarily in the stratosphere, with larger quantities in the troposphere and a monotonic decrease with increasing altitude in the stratosphere. MIPAS CCl4 measurements have been compared with independent measurements from other satellite and balloon-borne remote sounders, showing a good agreement between the different datasets.CCl4 trends are calculated as a function of both latitude and altitude. Negative trends of about text">-10 to -15 pptv decade-1 (-10 to -30 % decade-1) are found at all latitudes in the upper troposphere-lower stratosphere region, apart from a region in the southern midlatitudes between 50 and 10 hPa where the trend is positive with values around 5-10 pptv decade-1 (15-20 % decade-1). At the lowest altitudes sounded by MIPAS, we find trends consistent with those determined on the basis of long-term ground

  18. The chemokines CCL11, CCL20, CCL21, and CCL24 are preferentially expressed in polarized human secondary lymphoid follicles.

    Science.gov (United States)

    Buri, Caroline; Gutersohn, Andreas; Hauser, Chantal; Kappeler, Andreas; Mueller, Christoph

    2004-10-01

    Chemokines regulate cellular trafficking to and from lymphoid follicles. Here, the distribution pattern of four CCL chemokines is defined by in situ hybridization in human lymphoid follicles from tonsils and lymph nodes (LNs) of newborns and adults. Cells expressing CCL11 (eotaxin) and CCL20 (Exodus) were preferentially located within follicles, while cells expressing CCL21 (secondary lymphoid-tissue chemokine) and CCL24 (eotaxin-2) mRNA were almost exclusively found in the perifollicular areas. Hence, the two CCR3-binding chemokines, CCL11 and CCL24, showed a mutually exclusive expression pattern in the intra- and extra-follicular areas, respectively. Chemokine gene expression paralleled follicular maturation: in tonsils, where approximately 80% of follicles are polarized, CCL11 and CCL20 mRNA-positive cells were detected more frequently than in lymph nodes from adults, where about half of follicles are non-polarized. No intrafollicular chemokine expression was detectable in the primary follicles from newborns. Extrafollicular cells expressing CCL21 and CCL24 were again more frequent in tonsils than in LNs from adults. The observed preferential presence of cells expressing CC chemokines in polarized human lymphoid follicles indicates that chemokines are not only instrumental in the induction of follicle formation, but may also be involved in their further differentiation.

  19. Hepatoprotective activity of Mentha arvensis Linn. leaves against CCL4 induced liver damage in rats

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    Kalpana Patil

    2012-05-01

    Full Text Available Objective: To study the Hepatoprotective activity of ethanol, chloroform and aqueous extracts of Mentha arvensis leaves against CCL4 induced liver damage in rats. Methods: Hepatotoxicity was induced by CCL4 and the biochemical parameters such as serum glutamate pyruvate transminase (sGPT, serum glutamate oxaloacetate transaminase (sGOT, alkaline phosphatase (sALP, serum bilirubin (sB and histopathological changes in liver were studied along with silymarin as standard Hepatoprotective agents. Results: The Phytochemical investigation of the extracts showed presence of flavonoids, steroids, triterpenoids, alkaloids, glycosides, carbohydrates, tannins, phenolic compounds. Treatment of the rats with chloroform, ethanol and aqueous extract with CCL 4 administration caused a significant reduction in the values of sGOT, sGPT, sALP and sB (P<0.01 almost comparable to the silymarin. The Hepatoprotective was confirmed by histopathological examination of the liver tissue of control and treated animals. Conclusions: From the results it can be concluded that Mentha arvensis possesses Hepatoprotective effect against CCL4 induced liver damage in rats.

  20. Protective effect of Cucurbita pepo fruit peel against CCl4 induced neurotoxicity in rat.

    Science.gov (United States)

    Zaib, Sania; Khan, Muhammad Rashid

    2014-11-01

    Cucurbita pepo is a common vegetable used all over the world. In folk medicine it is used in gastroenteritis, hepatorenal and in brain anomalies. In the present study, protective effect of Cucurbita pepo fruit peel against CCl4-induced neurotoxicity in rats was investigated. In this study, 36 Sprague-Dawley female rats (190±15 g) were randomly divided into 6 groups of 6 rats each. Group I was given 1 ml/kg bw (body weight) of corn oil intraperotoneally (i.p); Group II, III and IV were treated with 20% CCl4 in corn oil (1ml/kg bw i.p.). However, animals of Group III and IV were also treated with CPME (methanol extract of C. pepo fruit peel) at 200 and 400mg/kg bw respectively. Animals of Group V and VI were administered only with CPME at 200 and 400mg/kg bw respectively. These treatments were administered 3 days a week for two weeks. Administration of CCl4 cause acute neurotoxicity as depicted by significant depletion (p<0.05) in the activities of antioxidant enzymes; catalase, superoxide dismutase, peroxidase, glutathione reductase, glutathione-S-transferase, glutathione peroxidase, quinone reductase, while enhanced the γ-glutamyl transferase level in brain samples. CCl4 intoxication decreased the reduced glutathione (GSH) level whereas markedly (p<0.05) enhanced lipid peroxidation in brain samples. Co-treatment of CPME significantly (p<0.05) protected the brain tissues against CCl4 constituted injuries by restoring activities of antioxidant enzymes and ameliorated lipid peroxidation in a dose dependent fashion. These neuroprotective effects might be due to the presence of antioxidant constituents.

  1. Protective effect of Curcuma longa L. extract on CCl4-induced acute hepatic stress.

    Science.gov (United States)

    Lee, Geum-Hwa; Lee, Hwa-Young; Choi, Min-Kyung; Chung, Han-Wool; Kim, Seung-Wook; Chae, Han-Jung

    2017-02-01

    The Curcuma longa L. (CLL) rhizome has long been used to treat patients with hepatic dysfunction. CLL is a member of the ginger family of spices that are widely used in China, India, and Japan, and is a common spice, coloring, flavoring, and traditional medicine. This study was performed to evaluate the hepatoprotective activity of CLL extract and its active component curcumin in an acute carbon tetrachloride (CCl 4 )-induced liver stress model. Acute hepatic stress was induced by a single intraperitoneal injection of CCl 4 (0.1 ml/kg body weight) in rats. CLL extract was administered once a day for 3 days at three dose levels (100, 200, and 300 mg/kg/day) and curcumin was administered once a day at the 200 mg/kg/day. We performed alanine transaminase (ALT) and aspartate transaminase (AST). activity analysis and also measured total lipid, triglyceride, and cholesterol levels, and lipid peroxidation. At 100 g CLL, the curcuminoid components curcumin (901.63 ± 5.37 mg/100 g), bis-demethoxycurcumin (108.28 ± 2.89 mg/100 g), and demethoxycurcumin (234.85 ± 1.85 mg/100 g) were quantified through high liquid chromatography analysis. In CCl 4 -treated rats, serum AST and ALT levels increased 2.1- and 1.2-fold compared with the control. AST but not ALT elevation induced by CCl 4 was significantly alleviated in CLL- and curcumin-treated rats. Peroxidation of membrane lipids in the liver was significantly prevented by CLL (100, 200, and 300 mg/kg/day) on tissue lipid peroxidation assay and immunostaining with anti-4HNE antibody. We found that CLL extract and curcumin exhibited significant protection against liver injury by improving hepatic superoxide dismutase (p < 0.05) and glutathione peroxidase activity, and glutathione content in the CCl 4 -treated group (p < 0.05), leading to a reduced lipid peroxidase level. Our data suggested that CLL extract and curcumin protect the liver from acute CCl 4 -induced injury in a rodent model by suppressing

  2. Pistacia chinensis: A Potent Ameliorator of CCl4 Induced Lung and Thyroid Toxicity in Rat Model

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    Kiran Naz

    2014-01-01

    Full Text Available In the current study protective effect of ethanol extract of Pistacia chinensis bark (PCEB was investigated in rats against CCl4 induced lung and thyroid injuries. PCEB dose dependently inhibited the rise of thiobarbituric acid-reactive substances, hydrogen peroxide, nitrite, and protein content and restored the levels of antioxidant enzymes, that is, catalase, peroxidase, superoxide dismutase, glutathione-S-transferase, glutathione reductase, glutathione peroxidase, γ-glutamyl transpeptidase, and quinone reductase in both lung and thyroid tissues of CCl4 treated rats. Decrease in number of leukocytes, neutrophils, and hemoglobin and T3 and T4 content as well as increase in monocytes, eosinophils, and lymphocytes count with CCl4 were restored to normal level with PCEB treatment. Histological study of CCl4 treated rats showed various lung injuries like rupture of alveolar walls and bronchioles, aggregation of fibroblasts, and disorganized Clara cells. Similarly, histology of CCl4 treated thyroid tissues displayed damaged thyroid follicles, hypertrophy, and colloidal depletion. However, PCEB exhibited protective behaviour for lungs and thyroid, with improved histological structure in a dose dependant manner. Presence of three known phenolic compounds, that is, rutin, tannin, and gallic acid, and three unknown compounds was verified in thin layer chromatographic assessment of PCEB. In conclusion, P. chinensis exhibited antioxidant activity by the presence of free radical quenching constituents.

  3. Protective effects of Carissa opaca fruits against CCl4-induced oxidative kidney lipid peroxidation and trauma in rat

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    Sumaira Sahreen

    2015-09-01

    Full Text Available Background: Carbon tetrachloride (CCl4 is a potent nephrotoxin, as it causes acute as well as chronic toxicity in kidneys. Therefore, this study was carried out to assess the pharmacological potential of different fractions of Carissa opaca fruits on CCl4-induced oxidative trauma in the kidney. Methods: The parameters studied in this respect were the kidney function tests viz, serum profile, urine profile, genotoxicity, characteristic morphological findings, and antioxidant enzymatic level of kidneys. Result: The protective effects of various fractions of C. opaca fruits against CCl4 administration were reviewed by rat renal function alterations. Chronic toxicity caused by 8-week treatment of CCl4 to the rats significantly decreased the pH level, activities of antioxidant enzymes, and glutathione contents, whereas a significant increase was found in the case of specific gravity, red blood cells, white blood cells, level of urea, and lipid peroxidation in comparison to control group. Administration of various fractions of C. opaca fruit with CCl4 showed protective ability against CCl4 intoxication by restoring the urine profile, activities of antioxidant enzymes, and lipid peroxidation in rat. CCl4 induction in rats also caused DNA fragmentation and glomerular atrophy by means of dilation, disappearance of Bowmen's space, congestion in the capillary loops, dilation in renal tubules, and foamy look of epithelial cells of tubular region, which were restored by co-admiration of various fractions of C. opaca. Conclusion: Results revealed that the methanolic fractions of C. opaca are the most potent and helpful in kidney trauma.

  4. Hepatic mitochondrial and microsomal recovery of rats intoxicated with CCl/sub 4/

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, T.; Hirai, Y.; Koga, N.; Tomokuni, K.

    1983-01-01

    The hepatic mitochondrial and microsomal recovery of rats intoxicated with CCl/sub 4/ was investigated with specific reference to the oxygen utilization of liver slices. In control rats, the major oxygen utilization of the liver slices was attributed to mitochondrial particles. Since the mitochondrial oxygen utilization was inhibited by cyanide, the microsomal oxygen utilization was induced by NADPH and phenobarbital (a substrate for microsomal mixed function oxidase). Changes in oxygen utilization were observed in the recovery course of rats intoxicated with CCl/sub 4/, and the recovery of mitochondria was found to be faster than that of microsomes. A sex difference was present in the recovery mechanism of the microsomes.

  5. Prevention of CCl4-induced liver damage by ginger, garlic and vitamin E.

    Science.gov (United States)

    Patrick-Iwuanyanwu, K C; Wegwu, M O; Ayalogu, E O

    2007-02-15

    The hepatoprotective effects of garlic (Allium sativum), ginger (Zingiber officinale) and vitamin E pre-treatment against carbon tetrachloride (CCl4)-induced liver damage in male wistar albino rats were investigated. Carbon tetrachloride (0.5 mL kg(-1) body weight) was administered after 28 days of feeding animals with diets containing ginger, garlic, vitamin E and various mixtures of ginger and garlic. Serum alanine amino transferase, aspartate amino transferase and alkaline phosphatase levels, 24 h after CCl4 administration, decreased significantly (p hepatic cells decreased remarkably in pre-treated rats.

  6. Rat Plasma Oxidation Status After Nigella Sativa L. Botanical Treatment in CCL(4)-Treated Rats.

    Science.gov (United States)

    Soleimani, Hengameh; Ranjbar, Akram; Baeeri, Maryam; Mohammadirad, Azadeh; Khorasani, Reza; Yasa, Narguess; Abdollahi, Mohammad

    2008-01-01

    ABSTRACT Nigella sativa Linn. (family Ranunculaceae), commonly known as black cumin, is native to the Mediterranean area and has been used for thousands of years as a health and beauty aid. The present study investigated the protective effects of Nigella sativa (NS) extract (NSE) and oil (NSO) on CCl(4)-induced nitrosative stress and protein oxidation in rat. CCl(4) (0.8 mg/kg) was used as an aid for induction of nitrosative stress. In vitro antioxidant potential was tested in the presence of 2,4-dinitrophenylhyrdazine (DPPH) as an organic nitrogen radical. Doses of 0.2, 0.3, and 1 mg/kg of the NS extract and oil were administered to CCL(4)-treated rats for 10 days. At the end of treatment, blood was taken from rats under anesthesia and plasma was separated. The concentration of nitric oxide (NO), total antioxidant power (TAP), carbonyl molecules (CM) as measure of protein oxidation (PO), tumor necrosis factor-alpha (TNF-alpha), and total thiol molecules (TTM) were measured in plasma. In vitro evaluation of antioxidant effects of NSE and NSO showed that the highest antioxidant activity (80%) was observed with the concentration of 10 and 20 mg/ml, respectively, that were equal to vitamin E (200 mg/ml). Administration of CCL(4) increased plasma PO, NO, TNF-alpha and decreased TAP and TTM. Both NSE and NSO showed significant protection against CCl(4)-induced changes in biochemical parameters, but not dose-dependently. Doses of 0.3 and 1 mg/kg were more effective than doses of 0.2 mg/kg for both NSE and NSO, but dose of 1 mg/kg was the most effective one. The results indicate the potential of NS in preventing CCL(4)-induced toxic nitrosative stress. It is concluded that NS has marked antioxidant potentials that may be beneficial in alleviating complications of many illnesses related to oxidative/nitrosative stress in humans, but preclinical safety measures should be completed before clinical trials.

  7. Immune response CC Chemokines, CCL2 and CCL5 are associated with Pulmonary Sarcoidosis

    LENUS (Irish Health Repository)

    Palchevskiy, Vyacheslav

    2011-04-04

    Abstract Background Pulmonary sarcoidosis involves an intense leukocyte infiltration of the lung with the formation of non-necrotizing granulomas. CC chemokines (chemokine (C-C motif) ligand 2 (CCL2)-CCL5) are chemoattractants of mononuclear cells and act through seven transmembrane G-coupled receptors. Previous studies have demonstrated conflicting results with regard to the associations of these chemokines with sarcoidosis. In an effort to clarify previous discrepancies, we performed the largest observational study to date of CC chemokines in bronchoalveolar lavage fluid (BALF) from patients with pulmonary sarcoidosis. Results BALF chemokine levels from 72 patients affected by pulmonary sarcoidosis were analyzed by enzyme-linked immunosorbent assay (ELISA) and compared to 8 healthy volunteers. BALF CCL3 and CCL4 levels from pulmonary sarcoidosis patients were not increased compared to controls. However, CCL2 and CCL5 levels were elevated, and subgroup analysis showed higher levels of both chemokines in all stages of pulmonary sarcoidosis. CCL2, CCL5, CC chemokine receptor type 1 (CCR1), CCR2 and CCR3 were expressed from mononuclear cells forming the lung granulomas, while CCR5 was only found on mast cells. Conclusions These data suggest that CCL2 and CCL5 are important mediators in recruiting CCR1, CCR2, and CCR3 expressing mononuclear cells as well as CCR5-expressing mast cells during all stages of pulmonary sarcoidosis.

  8. Immune response CC chemokines CCL2 and CCL5 are associated with pulmonary sarcoidosis.

    Science.gov (United States)

    Palchevskiy, Vyacheslav; Hashemi, Nastran; Weigt, Stephen S; Xue, Ying Ying; Derhovanessian, Ariss; Keane, Michael P; Strieter, Robert M; Fishbein, Michael C; Deng, Jane C; Lynch, Joseph P; Elashoff, Robert; Belperio, John A

    2011-04-04

    Pulmonary sarcoidosis involves an intense leukocyte infiltration of the lung with the formation of non-necrotizing granulomas. CC chemokines (chemokine (C-C motif) ligand 2 (CCL2)-CCL5) are chemoattractants of mononuclear cells and act through seven transmembrane G-coupled receptors. Previous studies have demonstrated conflicting results with regard to the associations of these chemokines with sarcoidosis. In an effort to clarify previous discrepancies, we performed the largest observational study to date of CC chemokines in bronchoalveolar lavage fluid (BALF) from patients with pulmonary sarcoidosis. BALF chemokine levels from 72 patients affected by pulmonary sarcoidosis were analyzed by enzyme-linked immunosorbent assay (ELISA) and compared to 8 healthy volunteers. BALF CCL3 and CCL4 levels from pulmonary sarcoidosis patients were not increased compared to controls. However, CCL2 and CCL5 levels were elevated, and subgroup analysis showed higher levels of both chemokines in all stages of pulmonary sarcoidosis. CCL2, CCL5, CC chemokine receptor type 1 (CCR1), CCR2 and CCR3 were expressed from mononuclear cells forming the lung granulomas, while CCR5 was only found on mast cells. These data suggest that CCL2 and CCL5 are important mediators in recruiting CCR1, CCR2, and CCR3 expressing mononuclear cells as well as CCR5-expressing mast cells during all stages of pulmonary sarcoidosis.

  9. Effect of Calitropis Procera Aqueous Root Extract Against CCL4 ...

    African Journals Online (AJOL)

    ABUBAKAR

    ABSTRACT. The hepatocurative effect of aqueous root extract of Calitropis Procera on CCl4 induced hepatotoxicity in rabbits was studied in groups of rabbit and the levels of liver enzymes; aspartate amino transferase (AST), alanine amino transferase (ALT) and alkaline phosphatase (ALP). Serum concentrations of total ...

  10. The in vitro NADPH-dependent inhibition by CCl4 of the ATP-dependent calcium uptake of hepatic microsomes from male rats. Studies on the mechanism of the inactivation of the hepatic microsomal calcium pump by the CCl3 radical

    International Nuclear Information System (INIS)

    Srivastava, S.P.; Chen, N.Q.; Holtzman, J.L.

    1990-01-01

    The hepatotoxicity of CCl4 is mediated through its initial reduction by cytochrome P-450 to the CCl3 radical. This radical then damages important metabolic systems such as the ATP-dependent microsomal Ca2+ pump. Previous studies from our laboratory on isolated microsomes have shown that NADPH in the absence of toxic agents inhibits this pump. We have now found in in vitro incubations that CCl4 (0.5-2.5 mM) enhanced the NADPH-dependent inhibition of Ca2+ uptake from 28% without CCl4 to a maximum of 68%. These concentrations are in the range found in the livers and blood of lethally intoxicated animals and are toxic to cultured hepatocytes. The inhibition of Ca2+ uptake was due both to a decrease in the Ca2(+)-dependent ATPase and to an enhanced release of Ca2+ from the microsomes. The NADPH-dependent CCl4 inhibition was greater under N2 and was totally prevented by CO. GSH (1-10 mM) added during the incubation with CCl4 prevented the inhibition. This protection was also seen when the incubations were performed under nitrogen. When samples were preincubated with CCl4, the CCl4 metabolism was stopped, and then the Ca2+ uptake was determined; GSH reversed the CCl4 inhibition of Ca2+ uptake. This reversal showed saturation kinetics for GSH with two Km values of 0.315 and 93 microM when both the preincubation and the Ca2+ uptake were performed under air, and 0.512 and 31 microM when both were performed under nitrogen. Cysteine did not prevent the NADPH-dependent CCl4 inhibition of Ca2+ uptake. CCl4 increased lipid peroxidation in air, but no lipid peroxidation was seen under nitrogen. Lipid peroxidation was only modestly reversed by GSH. GSH did not remove 14C bound to samples preincubated with the 14CCl4

  11. Effects of Nigella sativa L. and Urtica dioica L. on selected mineral status and hematological values in CCl4-treated rats.

    Science.gov (United States)

    Meral, Ismail; Kanter, Mehmet

    2003-01-01

    This study was designed to investigate the effects of Nigella sativa L. (NS), known as black seed, or/and Urtica dioica L. (UD), known as stinging nettle root, treatments on serum Na, K, Cl, and Ca levels and some hematological values of CCl4-treated rats. Sixty healthy male Sprague-Dawley rats, weighing 250-300 g, were randomly allotted into 1 of 4 experimental groups: A (CCl4-only treated), B (CCl4+UD treated), C (CCl4+NS treated), and D (CCl4+UD+NS treated), each containing 15 animals. All groups received CCl4 (0.8 mL/kg of body weight, subcutaneously, twice a week for 90 d starting d 1). In addition, B, C, and D groups also received the daily ip injection of 0.2 mL/kg NS and/or 2 mL/kg UD oils for 45 d starting d 46. Group A, on the other hand, received only 2 mL/kg normal saline solution for 45 d starting d 46. Blood samples for the biochemical analysis were taken by cardiac puncture from five randomly chosen rats in each treatment group at the beginning, d 45, and d 90 of the experiment. The CCl4 treatment for 45 d significantly (p0.05) the serum Na and Cl levels. NS or UD treatments (alone or combination) for 45 d starting d 46 significantly (p<0.05) decreased the elevated serum K and Ca levels and also increased (p<0.05) the reduced RBC, WBC, PCV, and Hb levels. It is concluded that NS and/or UD treatments might ameliorate the CCl4-induced disturbances of anemia, some minerals, and body's defense mechanism in CCl4-treated rats.

  12. Acetonic and Methanolic Extracts of Heterotheca inuloides, and Quercetin, Decrease CCl4-Oxidative Stress in Several Rat Tissues

    Science.gov (United States)

    Coballase-Urrutia, Elvia; Pedraza-Chaverri, José; Cárdenas-Rodríguez, Noemí; Huerta-Gertrudis, Bernardino; García-Cruz, Mercedes Edna; Montesinos-Correa, Hortencia; Sánchez-González, Dolores Javier; Camacho-Carranza, Rafael; Espinosa-Aguirre, Jesús Javier

    2013-01-01

    The present study was designed to test the hypothesis that the acetonic and methanolic extracts of H. inuloides prevent carbon tetrachloride-(CCl4) induced oxidative stress in vital tissues. Pretreatment with both H. inuloides extracts or quercetin attenuated the increase in serum activity of alkaline phosphatase (ALP), total bilirubin (BB), creatinine (CRE), and creatine kinase (CK), and impeded the decrease of γ-globulin (γ-GLOB) and albumin (ALB) observed in CCl4-induced tissue injury. The protective effect was confirmed by histological analysis with hematoxylin-eosin and periodic acid/Schiff's reagent. Level of lipid peroxidation was higher in the organs of rats exposed to CCl4 than in those of the animals treated with Heterohteca extracts or quercetin, and these showed levels similar to the untreated group. Pretreatment of animals with either of the extracts or quercetin also prevented the increase of 4-hydroxynonenal and 3-nitrotyrosine. Pretreatment with the plant extracts or quercetin attenuated CCl4 toxic effects on the activity of several antioxidant enzymes. The present results strongly suggest that the chemopreventive effect of the extracts used and quercetin, against CCl4 toxicity, is associated with their antioxidant properties and corroborated previous results obtained in liver tissue. PMID:23365610

  13. Mechanism of the Inhibitory Effects of Eucommia ulmoides Oliv. Cortex Extracts (EUCE in the CCl4-Induced Acute Liver Lipid Accumulation in Rats

    Directory of Open Access Journals (Sweden)

    Chang-Feng Jin

    2013-01-01

    Full Text Available Eucommia ulmoides Oliv. (EU has been used for treatment of liver diseases. The protective effects of Eucommia Ulmoides Oliv. cortex extracts (EUCE on the carbon tetrachloride- (CCl4- induced hepatic lipid accumulation were examined in this study. Rats were orally treated with EUCE in different doses prior to an intraperitoneal injection of 1 mg/kg CCl4. Acute injection of CCl4 decreased plasma triglyceride but increased hepatic triglyceride and cholesterol as compared to control rats. On the other hand, the pretreatment with EUCE diminished these effects at a dose-dependent manner. CCl4 treatment decreased glutathione (GSH and increased malondialdehyde (MDA accompanied by activated P450 2E1. The pretreatment with EUCE significantly improved these deleterious effects of CCl4. CCl4 treatment increased P450 2E1 activation and ApoB accumulation. Pretreatment with EUCE reversed these effects. ER stress response was significantly increased by CCl4, which was inhibited by EUCE. One of the possible ER stress regulatory mechanisms, lysosomal activity, was examined. CCl4 reduced lysosomal enzymes that were reversed with the EUCE. The results indicate that oral pretreatment with EUCE may protect liver against CCl4-induced hepatic lipid accumulation. ER stress and its related ROS regulation are suggested as a possible mechanism in the antidyslipidemic effect of EUCE.

  14. The extraction behaviour of As(III) and As(V) in APDC-CCl4 system

    International Nuclear Information System (INIS)

    Yang Ruiying; Zhu Xuping

    1997-01-01

    The extraction and back-extraction behaviour of As(III) and As(V) in APDC-CCl 4 system have been studied by using 76 As trace technique. As(III) can be extracted quantitatively by APDC-CCl 4 system at pH = 1-3. As(V) can be extracted after being reduced to As(III) by Na 2 S 2 O 3 . Water with high pH value can be used for back-extraction. The method can be applied in the separation of inorganic As(III) and As(V) in water quality inspection

  15. Antioxidant and protective effect of inulin and catechin grafted inulin against CCl4-induced liver injury.

    Science.gov (United States)

    Liu, Jun; Lu, Jian-feng; Wen, Xiao-yuan; Kan, Juan; Jin, Chang-hai

    2015-01-01

    In this study, the antioxidant activity and hepatoprotective effect of inulin and catechin grafted inulin (catechin-g-inulin) against carbon tetrachloride (CCl4)-induced acute liver injury were investigated. Results showed that both inulin and catechin-g-inulin had moderate scavenging activity on superoxide radical, hydroxyl radical and H2O2, as well as lipid peroxidation inhibition effect. The antioxidant activity decreased in the order of Vc > catechin >catechin-g-inulin > inulin. Administration of inulin and catechin-g-inulin could significantly reduce the elevated levels of serum aspartate transaminase, alanine transaminase and alkaline phosphatase as compared to CCl4 treatment group. Moreover, inulin and catechin-g-inulin significantly increased the levels of hepatic superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione and total antioxidant capacity, whereas markedly decreased the malondialdehyde level when compared with CCl4 treatment group. Notably, catechin-g-inulin showed higher hepatoprotective effect than inulin. In addition, the hepatoprotective effect of catechin-g-inulin was comparable to positive standard of silymarin. Our results suggested that catechin-g-inulin had potent antioxidant activity and potential protective effect against CCl4-induced acute liver injury. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Constraining the carbon tetrachloride (CCl4) budget using its global trend and inter-hemispheric gradient

    Science.gov (United States)

    Liang, Qing; Newman, Paul A.; Daniel, John S.; Reimann, Stefan; Hall, Bradley D.; Dutton, Geoff; Kuijpers, Lambert J. M.

    2014-07-01

    Carbon tetrachloride (CCl4) is a major anthropogenic ozone-depleting substance and greenhouse gas and has been regulated under the Montreal Protocol. However, the near-zero 2007-2012 emissions estimate based on the UNEP reported production and feedstock usage cannot be reconciled with the observed slow decline of atmospheric concentrations and the inter-hemispheric gradient (IHG) for CCl4. Our 3-D model simulations suggest that the observed IHG (1.5 ± 0.2 ppt for 2000-2012) is primarily caused by ongoing current emissions, while ocean and soil losses and stratosphere-troposphere exchange together contribute a small negative gradient (~0 - -0.3 ppt). Using the observed CCl4 global trend and IHG, we deduce that the mean global emissions for the 2000-2012 period are 393445 Gg/yr (~30% of the peak 1980s emissions) and a corresponding total lifetime of 353732 years.

  17. Oral Delivery of Curcumin Polymeric Nanoparticles Ameliorates CCl4-Induced Subacute Hepatotoxicity in Wistar Rats

    Directory of Open Access Journals (Sweden)

    Gregory Marslin

    2018-05-01

    Full Text Available Curcumin is the major bioactive compound of Curcuma longa, an important medicinal plant used in traditional herbal formulations since ancient times. In the present study, we report that curcumin nanoparticles (ηCur protects Wistar rats against carbon tetrachloride (CCl4-induced subacute hepatotoxicity. Nanoparticles of sizes less than 220 nm with spherical shape were prepared using PLGA and PVA respectively as polymer and stabilizer. Test animals were injected via intraperitoneal route with 1 mL/kg CCl4 (8% in olive oil twice a week over a period of 8 weeks to induce hepatotoxicity. On the days following the CCl4 injection, test animals were orally administered with either curcumin or its equivalent dose of ηCur. Behavioural observation, biochemical analysis of serum and histopathological examination of liver of the experimental animals indicated that ηCur offer significantly higher hepatoprotection compared to curcumin.

  18. Role of CCL-2, CCR-2 and CCR-4 in cerulein-induced acute pancreatitis and pancreatitis-associated lung injury.

    Science.gov (United States)

    Frossard, Jean Louis; Lenglet, Sébastien; Montecucco, Fabrizio; Steffens, Sabine; Galan, Katia; Pelli, Graziano; Spahr, Laurent; Mach, Francois; Hadengue, Antoine

    2011-05-01

    Acute pancreatitis is an inflammatory process of variable severity. Leucocytes are thought to play a key role in the development of pancreatitis and pancreatitis-associated lung injury. The interactions between inflammatory cells and their mediators are crucial for determining tissue damage. Monocyte chemoattractant protein-1 (or CCL-2), CCR-2 and CCR-4 are chemokines and chemokine receptors involved in leucocyte trafficking. The aim of the study was to evaluate the role of the CCL-2, CCR-2 and CCR-4 chemokine receptors in the pathogenesis of cerulein-induced pancreatitis and pancreatitis-associated lung injury. To address the role of CCL-2, CCR-2 and CCR-4 that attracts leucocytes cells in inflamed tissues, pancreatitis was induced by administering supramaximal doses of cerulein in mice that do not express CCL-2, CCR-2 or CCR-4. The severity of pancreatitis was measured by serum amylase, pancreatic oedema and acinar cell necrosis. Lung injury was quantitated by evaluating lung microvascular permeability and lung myeloperoxidase activity. Chemokine and chemokine-receptor expression were quantitated by real-time PCR. The nature of inflammatory cells invading the pancreas and lungs was studied by immunostaining. The authors have found that pancreas CCL-2 and CCR-2 levels rise during pancreatitis. Both pancreatitis and the associated lung injury are blunted, but not completely prevented, in mice deficient in CCL-2, whereas the deficiency in either CCR-2 or CCR-4 does not reduce the severity of both the pancreatitis and the lung injury. The amounts of neutrophils and monocyte/macrophages (MOMA)-2 cells were significantly lower in mice deficient in CCL-2 compared with their sufficient littermates. These results suggest that CCL-2 plays a key role in pancreatitis by modulating the infiltration by neutrophils and MOMA-2 cells, and that its deficiency may improve the outcome of the disease.

  19. Effect of extracts from araticum (Annona crassiflora on CCl4-induced liver damage in rats

    Directory of Open Access Journals (Sweden)

    Roberta Roesler

    2011-03-01

    Full Text Available The influence of ethanolic extracts of Annona crassiflora on the activities of hepatic antioxidant enzymes was examined. Extracts of A. crassiflora seeds and peel were administered orally (50 mg of galic acid equivalents.kg-1 to Wistar rats for 14 consecutive days followed by a single oral dose of carbon tetrachloride (CCl4, 2 g.kg-1. Lipid peroxidation and the activities of hepatic catalase (CAT, cytochromes P450 (CP450 and b5, glutathione peroxidase (GPx, glutathione reductase (GRed, superoxide dismutase (SOD, and the content of glutathione equivalents (GSH were evaluated. The treatment with CCl4 increased lipid peroxidation, the level of GSH equivalents and the content of cytochrome b5 by 44, 140 and 32%, respectively, with concomitant reductions of 23, 34 and 39% in the activities of CAT, SOD, and CP450, respectively. The treatment with A. crassiflora seeds and peel extracts alone inhibited lipid peroxidation by 27 and 22%, respectively without affecting the CP450 content. The pretreatment with the A. crassiflora extracts prevented the lipid peroxidation, the increase in GSH equivalents and the decrease in CAT activity caused by CCl4, but it had no effect on the CCl4-mediated changes in CP450 and b5 and SOD. These results show that A. crassiflora seeds and peel contain antioxidant activity in vivo that could be of potential therapeutic use.

  20. Breviscapine ameliorates CCl4‑induced liver injury in mice through inhibiting inflammatory apoptotic response and ROS generation.

    Science.gov (United States)

    Liu, Yu; Wen, Pei-Hao; Zhang, Xin-Xue; Dai, Yang; He, Qiang

    2018-05-02

    Acute liver injury is characterized by fibrosis, inflammation and apoptosis, leading to liver failure, cirrhosis or cancer and affecting the clinical outcome in the long term. However, no effective therapeutic strategy is currently available. Breviscapine, a mixture of flavonoid glycosides, has been reported to have multiple biological functions. The present study aimed to investigate the effects of breviscapine on acute liver injury induced by CCl4 in mice. C57BL/6 mice were subjected to intraperitoneal injection with CCl4 for 8 weeks with or without breviscapine (15 or 30 mg/kg). Mice treated with CCl4 developed acute liver injury, as evidenced by histological analysis, Masson trichrome and Sirius Red staining, accompanied with elevated levels of alanine aminotransferase and aspartate aminotransferase. Furthermore, increases in pro‑inflammatory cytokines, chemokines and apoptotic factors, including caspase‑3 and poly(ADP ribose) polymerase‑2 (PARP‑2), were observed. Breviscapine treatment significantly and dose‑dependently reduced collagen deposition and the fibrotic area. Inflammatory cytokines were downregulated by breviscapine through inactivating Toll‑like receptor 4/nuclear factor-κB signaling pathways. In addition, co‑administration of breviscapine with CCl4 decreased the apoptotic response by enhancing B‑cell lymphoma-2 (Bcl‑2) levels, while reducing Bcl‑2‑associated X protein, apoptotic protease activating factor 1, caspase‑3 and PARP activity. Furthermore, CCl4‑induced oxidative stress was blocked by breviscapine through improving anti‑oxidants and impeding mitogen‑activated protein kinase pathways. The present study highlighted that breviscapine exhibited liver‑protective effects against acute hepatic injury induced by CCl4 via suppressing inflammation and apoptosis.

  1. Comparison of hepatic fibrosis models and associated hepatic fibronectin expression in Wistar rats treated by bile duct ligation and CCl4

    Directory of Open Access Journals (Sweden)

    LIU Xiaoya

    2015-02-01

    Full Text Available ObjectiveTo compare serum biochemical parameters, liver pathology, and fibronectin (FN expression in Wister rats with hepatic fibrosis induced by bile duct ligation (BDL and carbon tetrachloride (CCl4. MethodsNinety healthy male Wister rats were assigned to CCl4 model (n=44, CCl4 control (n=6, BDL model (n=30, and BDL control groups (n=10. Animal models of hepatic fibrosis were established by intraperitoneal injection of olive oil solution containing 50% CCl4 in the CCl4 model group and by BDL in the BDL group. General conditions of rats were examined. Expression of serum alanine aminotransferase (ALT, serum aspartate aminotransferase (AST, total bilirubin (TBil, and direct bilirubin (DBil was measured by biochemical analysis. Expression of serum hyaluronic acid (HA and laminin (LN was measured by ELISA assay. Pathological changes in liver tissue were examined through hematoxylin-eosin and Masson staining. Expression of FN was assayed by immunohistochemistry. Comparison between groups was made by t test. ResultsSerum biochemical analysis showed that TBil and DBil levels in BDL model rats increased to and maintained at relatively high levels from day 7 after surgery (P<0.05; these two parameters in CCl4 model rats increased gradually from week 2 and peaked at week 8 after injection (P<0.05. The indicators of hepatic fibrosis, i.e., HA and LN levels, were significantly higher in the BDL model group than in the CCl4 model group. Pathologically, the CCl4 model group showed diffuse fatty degeneration of liver cells, with extremely significant fiber interval formation in the portal area - portal area or the portal area - central vein; the BDL model group showed coexistence of significant intrahepatic bile duct hyperplasia, inflammatory cell infiltration, and fiber interval formation. In the BDL model group, FN expression was dispersive and irregular with thin fibrous tissues; in the CCl4 model group, FN was mostly expressed in the interlobular septa

  2. Preventive and curative effects of Cocculus hirsutus (Linn. Diels leaves extract on CCl4 provoked hepatic injury in rats

    Directory of Open Access Journals (Sweden)

    Lavanya Goodla

    2017-12-01

    Full Text Available The present study was designed to estimate the protective or curative potency of an extract from Cocculus hirsutus leaves against CCl4 intoxication via its antioxidant property in rats. Liver enzyme markers (SGOT, SGPT, ALP, LDH, and bilirubin and oxidative stress markers {lipid peroxidation (LPO, enzymatic antioxidants [superoxide dismutase, catalase and glutathione peroxidase] and non-enzymatic antioxidants [reduced glutathione, vitamin C and E]} were analyzed by spectrophotometry. Histopathological studies on hepatic tissue were also performed by the method of Hematoxylin and Eosin staining. Rats administrated with 30% CCl4 in olive oil intraperitoneally resulted in significant increase in the levels of SGOT, SGPT, ALP, LDH, and bilirubin compared to control rats. Significant elevation of hepatic LPO and depletion of enzymatic and non-enzymatic antioxidants levels were observed in CCl4 induced rats. When CCl4 induced rats were co-treated with C. hirsutus at doses of 250 and 500 mg/kg b·wt, all the altered levels of liver marker enzymes and oxidative stress markers were restored to near control values. Histopathological studies provided direct evidence of the hepatoprotective effect of C. hirsutus. In conclusion, extract from C. hirsutus could protect the liver from CCl4-induced oxidative damage, by scavenging the free radicals generated during the metabolism of CCl4. Keywords: Antioxidants, Carbon tetrachloride, Cocculus hirsutus, Hepatoprotective effect, Lipid peroxidation

  3. Lycium barbarum polysaccharides improve CCl4-induced liver fibrosis, inflammatory response and TLRs/NF-kB signaling pathway expression in wistar rats.

    Science.gov (United States)

    Gan, Fang; Liu, Qing; Liu, Yunhuan; Huang, Da; Pan, Cuiling; Song, Suquan; Huang, Kehe

    2018-01-01

    Lycium barbarum polysaccharides (LBPs) have multiple biological and pharmacological functions, including antioxidant, anti-inflammatory and anticancer activities. This research was conducted to evaluate whether LBPs could alleviate carbon tetrachloride (CCl 4 )-induced liver fibrosis and the underlying signaling pathway mechanism. Fifty male wistar rats were randomly allocated to five groups (n=10): control, CCl 4 and CCl 4 with 400, 800 or 1600mg/kg LBPs, respectively. Each wistar rat from each group was used for blood and tissue collections at the end of experiment. The results showed that CCl 4 induced liver fibrosis as demonstrated by increasing histopathological damage, α-smooth muscle actin expression, aspartate transaminase activities, alkaline phosphatase activities and alanine aminotransferase activities. LBPs supplementation alleviated CCl 4 -induced liver fibrosis as demonstrated by reversing the above parameters. In addition, CCl 4 treatment induced the oxidative injury, increased the mRNA levels of tumor necrosis factor-α, monocyte chemoattractant protein-1 and interleukin-1β, and up-regulated the protein expressions of toll-like receptor 4 (TLR4), TLR2, myeloid differentiation factor 88, nuclear factor-kappa B (NF-kB) and p-p65. LBPs supplementation alleviated CCl 4 -induced oxidative injury, inflammatory response and TLRs/NF-kB signaling pathway expression by reversing the above some parameters. These results suggest that the alleviating effects of LBPs on CCl 4 -induced liver fibrosis in wistar rats may be through inhibiting the TLRs/NF-kB signaling pathway expression. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Targeted knock down of CCL22 and CCL17 by siRNA during DC differentiation and maturation affects the recruitment of T subsets.

    Science.gov (United States)

    Kang, Shijun; Xie, Jianmin; Ma, Shudong; Liao, Wangjun; Zhang, Junyi; Luo, Rongcheng

    2010-01-01

    Chemokines secreted by DC are instrumental for DC to regulate their own migratory capacities and to recruit T lymphocytes during local tumour immune response. Using the recently developed chemokine protein arrays, we analyzed 38 chemokines associated with monocyte-derived DC (MoDC), including the CC family (CCL2, CCL3, CCL4, CCL17, CCL18, CCL22, CCL23, CCL24, CCL27) and the CXC family (CXCL3, CXCL5, CXCL7, CXCL8, CXCL16) chemokines. Our results indicate that MoDC largely inherit the chemokines constitutively expressed by monocytes, with a significant induction of CCL17, CCL22 and CCL23. Spent culture supernatant collected from MoDC exhibited chemotatic abilities to activate CD4(+), CD8(+), and CD25(+) Foxp3(+) regulatory T cells (Tregs). Selective knock down of CCL22 and CCL17 expression by siRNA decreased the ratios of CD4(+) to CD8(+), as well as the frequency of Tregs recruited by MoDC. Intratumoural injection of MoDC transfected with siCCL22 and siCCL17, significantly reduced the number of Tregs while increasing the number of infiltrating CD8(+) T cells in human tumour xenografts in athymic nude mice. This study demonstrates that chemokine expression of MoDC is complex and may change dynamically. Using siRNA to selectively knock down chemokines which are highly chemoattractive to Tregs may consequentially alter the lymphocyte populations recruited into the tumour microenvironment, therefore has the potency to provide insight into cellular interactions in cancer immunology. This may lead to a new strategy for DC vaccine development to improve cancer immunobiotherapy.

  5. Relevance of CCL3/CCR5 axis in oral carcinogenesis.

    Science.gov (United States)

    da Silva, Janine Mayra; Moreira Dos Santos, Tálita Pollyanna; Sobral, Lays Martin; Queiroz-Junior, Celso Martins; Rachid, Milene Alvarenga; Proudfoot, Amanda E I; Garlet, Gustavo Pompermaier; Batista, Aline Carvalho; Teixeira, Mauro Martins; Leopoldino, Andréia Machado; Russo, Remo Castro; Silva, Tarcília Aparecida

    2017-08-01

    The chemokine CCL3 is a chemotactic cytokine crucial for inflammatory cell recruitment in homeostatic and pathological conditions. CCL3 might stimulate cancer progression by promoting leukocyte accumulation, angiogenesis and tumour growth. The expression of CCL3 and its receptors CCR1 and CCR5 was demonstrated in oral squamous cell carcinoma (OSCC), but their role was not defined. Here, the functions of CCL3 were assessed using a model of chemically induced tongue carcinogenesis with 4-nitroquinoline-1-oxide (4NQO). Lineages of OSCC were used to analyse the effects of CCL3 in vitro . The 4NQO-induced lesions exhibited increased expression of CCL3, CCR1 and CCR5. CCL3 -/- and CCR5 -/- mice presented reduced incidence of tongue tumours compared to wild-type (WT) and CCR1 -/- mice. Consistently, attenuated cytomorphological atypia and reduced cell proliferation were observed in lesions of CCL3 -/- and CCR5 -/- mice. OSCC from CCL3 -/- mice exhibited lower infiltration of eosinophils and reduced expression of Egf, Fgf1, Tgf-β1, Vegfa, Vegfb, Itga-4, Vtn, Mmp-1a, Mmp-2 and Mmp-9 than WT mice. In vitro , CCL3 induced invasion and production of CCL5, IL-6, MMP -2, -8, -9. Blockage of CCL3 in vitro using α-CCL3 or Evasin-1 (a CCL3-binding protein) impaired tumour cell invasion. In conclusion, CCL3/CCR5 axis has pro-tumourigenic effects in oral carcinogenesis. The induction of inflammatory and angiogenic pathways and eosinophils recruitment appear to be the underlying mechanism explaining these effects. These data reveal potential protective effects of CCL3 blockade in oral cancer.

  6. Fine structure of the CCl3 UV absorption spectrum and CCl3 kinetics

    DEFF Research Database (Denmark)

    Ellermann, T.

    1992-01-01

    The UV gas-phase spectrum of CCl3 was recorded in the range 220-300 nm using pulse radiolysis of CHCl3/SF6 or CCl4/Ar gas mixtures. The UV spectrum exhibits a pronounced vibrational fine structure which is assigned to transition into the (C2A1'(3s)) Rydberg state. The vibronic progression has...

  7. A novel route to nanosized molybdenum boride and carbide and/or metallic molybdenum by thermo-synthesis method from MoO3, KBH4, and CCl4

    International Nuclear Information System (INIS)

    Li Yuanzhi; Fan Yining; Chen Yi

    2003-01-01

    Nanosized molybdenum boride and carbide were synthesized from MoO 3 , KBH 4 , and CCl 4 by thermo-synthesis method at lower temperature. The relative content of Mo, Mo 2 C, and molybdenum boride in the product was decided by the molar ratio between MoO 3 , KBH 4 , and CCl 4 . Increasing the molar ratio of CCl 4 to MoO 3 was favorable to the production of Mo 2 C. Increasing the molar ratio of KBH 4 to MoO 3 was favorable to the production of molybdenum boride. By carefully adjusting the reaction conditions and annealing in Ar at 900 deg. C, a single phase of MoB could be obtained

  8. The CCl4 action upon physiological indices in Lepus timidus and the protective role of some substances

    Directory of Open Access Journals (Sweden)

    Alina PAUNESCU

    2009-11-01

    Full Text Available Aim of this study is to demonstrate the hepatoprotective role of grape seed oil and Cynara scolymus leaf extract. This experiment lasted for 12 days performed on male and female rabbit. The animals were intoxicated in the latest day of experiment (day 12th with CCl4 in a dose of 30μl/100g body weight and a group of them was treated for 12 days with 0.4 mg/kg body weight/day of Cynara scolymus (artichoke leaf extract while another group was treated with grape seed oil (1ml/kg body weight/day. Intoxication with CCl4 caused an increase a glycemia and a number of leukocytes, decrease cholesterol, triglycerides value, and a number of erythrocytes. We observed that the extract of Cynara scolymus leaf and the grape seed oil had a protective effect against CCl4 intoxication.

  9. Surface termination dependence of the reactivity of single crystal hematite with CCl 4

    Science.gov (United States)

    Camillone, Nicholas, III; Adib, Kaveh; Fitts, Jeffrey P.; Rim, Kwang T.; Flynn, George W.; Joyce, S. A.; Osgood, Richard M.

    2002-06-01

    We describe ultrahigh vacuum Auger electron spectrometric measurements of the uptake of chlorine following the room temperature exposure of single crystal hematite, α-Fe2O3, to CCl4. We compare the surface chemistry of two specific surface phases formed on the basal plane of α-Fe2O3: the Fe3O4(1 1 1)-(2×2) ;selvedge; and the α-Fe2O3/Fe1-xO ;biphase.; For Fe3O4(1 1 1)-(2×2) an estimated saturation level of Cl of ∼75% of a monolayer is readily attained. Carbon uptake is well below that expected for simple stoichiometric dissociative chemisorption, consistent with desorption of organic products during the surface reaction. Low energy electron diffraction measurements suggest that, dependent upon preparation procedures, at least two types of α-Fe2O3/Fe1-xO biphase structures can be formed. Surprisingly, upon exposure to CCl4, Cl uptake does not occur on either of these biphase surfaces, despite the fact that these surfaces are thought to have the same surface concentrations of iron and oxygen as Fe3O4(1 1 1). The dramatic difference between the reactivity of the Fe3O4 and biphase surfaces suggests that the active site for the dissociative adsorption of CCl4 on Fe3O4(1 1 1)-(2×2) comprises both an iron cation and an oxygen anion with a surface-normal-oriented dangling bond that is uncapped by iron cations. Electron stimulated and thermal desorption of Cl from the saturated Fe3O4(1 1 1)-(2×2) selvedge is also reported.

  10. 67Ga in transferrin-unbound form is taken up by inflamed liver of mouse treated with CCl4

    International Nuclear Information System (INIS)

    Ohkubo, Yasuhito; Sasayama, Akio; Takegahara, Ikumi; Katoh, Shinsuke; Abe, Kenichi; Kohno, Hiroyuki; Kubodera, Akiko.

    1990-01-01

    In order to investigate whether or not transferrin is involved in the uptake of 67 Ga by inflamed liver (acute inflammatory tissues) the uptake of 67 Ga by the liver of mice treated with carbon tetrachloride (CCl 4 ) was studied. The serum GPT value reached its maximum on the 1st day after the CCl 4 treatment. The uptake of 67 Ga by the liver also reached its maximum on the 1st day after the CCl-4 treatment and the amount uptake into inflamed liver was about 6 times that uptaken into normal liver. On the other hand, the uptake of 125 I-transferrin into inflamed liver on the 1st day after CCl 4 treatment was only about 1.6 times that into normal liver. Moreover, cold Fe 3+ decreased the uptake of 67 Ga by normal liver but increased the uptake of 67 Ga by inflamed liver. These results show that transferrin plays an important role in the uptake of 67 Ga by normal liver but not by inflamed liver, i.e. 67 Ga in the transferrin-unbound form is preferentially taken up by inflamed liver. (author)

  11. Chemistry of CCl 4 on Fe 3O 4(1 1 1)-(2 × 2) surfaces in the presence of adsorbed D 2O studied by temperature programmed desorption

    Science.gov (United States)

    Adib, K.; Totir, G. G.; Fitts, J. P.; Rim, K. T.; Mueller, T.; Flynn, G. W.; Joyce, S. A.; Osgood, R. M.

    2003-07-01

    Temperature programmed desorption (TPD) was used to study surface reactions of Fe 3O 4(1 1 1)-(2 × 2) sequentially exposed, at ˜100 K, to vapor-phase D 2O and CCl 4. Previous TPD and XPS results have indicated that in the absence of D 2O, CCl 4 dissociatively adsorbs on Fe 3O 4(1 1 1) producing chemisorbed Cl and CCl 2. Subsequent heating of the surface results in abstraction of lattice iron and oxygen atoms and causes them to desorb as FeCl 2 and OCCl 2, respectively. This study shows that when this Fe 3O 4 surface is exposed only to D 2O, TPD measures a rich surface chemistry with multiple desorption events extending as high as ˜800 K, indicating dissociative adsorption of D 2O on the Fe 3O 4(1 1 1) surface. After sequential exposure to D 2O and then CCl 4, the production of FeCl 2 and OCCl 2 from adsorbed CCl 4 is suppressed, indicating that D 2O fragments block the surface reactive sites.

  12. Protective Effect of γ-Irradiated Dried Powder of Artichoke Leaves against CCl4 Oxidative Stress Induced in Rat Liver

    International Nuclear Information System (INIS)

    Hamza, R.G.; El shahat, A.N.; Mekawey, H.M.S.

    2012-01-01

    Liver injuries are one of the most degenerative worldwide diseases and can lead to different complications. Artichoke (Cynara scolymus L.) is full of natural antioxidants and has hepato protective effect against liver toxicity. Gamma irradiation has been widely used as a first choice sterilization method of raw medicinal plants to be used in the phytotherapic industry worldwide .This study was designed to investigate the effect of dietary supplementation with γ- irradiated artichoke against carbon tetrachloride (CCl 4 )-induced oxidative stress and hepatotoxicity. The results of high performance liquid chromatography (HPLC) analysis of artichoke leaves indicated that the value of some of the main phenolic constituents was elevated under the effect of γ-irradiation (10 KGy). CCl 4 administration resulted in significant increase in the activity of serum alkaline phosphatase, gamma glutamyl transferase and transaminase in addition to an increase in the level of total bilirubine, malondialdehyde (MDA), glucose and the concentration of some lipid contents. Furthermore, CCl 4 administration reduced glutathione content, superoxides dismutase (SOD) and catalase (CAT) activity as well as a remarkable decrease in the level of insulin and high density lipoprotein-cholesterol was observed. In CCl 4 -treated rats dietary supplemented with either raw or γ-irradiated artichoke, a significant amelioration was observed on the adverse effects of the above mentioned parameters induced by CCl 4 administration. The present findings concluded that artichoke may be useful, as dietary supplement and possess phenolic compounds, for the prevention of oxidative stress-induced hepatotoxicity

  13. Beneficial impact of CCL2 and CCL12 neutralization on experimental malignant pleural effusion.

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    Antonia Marazioti

    Full Text Available Using genetic interventions, we previously determined that C-C motif chemokine ligand 2 (CCL2 promotes malignant pleural effusion (MPE formation in mice. Here we conducted preclinical studies aimed at assessing the specific therapeutic potential of antibody-mediated CCL2 blockade against MPE. For this, murine MPEs or skin tumors were generated in C57BL/6 mice by intrapleural or subcutaneous delivery of lung (LLC or colon (MC38 adenocarcinoma cells. Human lung adenocarcinoma cells (A549 were used to induce MPEs in severe combined immunodeficient mice. Intraperitoneal antibodies neutralizing mouse CCL2 and/or CCL12, a murine CCL2 ortholog, were administered at 10 or 50 mg/kg every three days. We found that high doses of CCL2/12 neutralizing antibody treatment (50 mg/kg were required to limit MPE formation by LLC cells. CCL2 and CCL12 blockade were equally potent inhibitors of MPE development by LLC cells. Combined CCL2 and CCL12 neutralization was also effective against MC38-induced MPE and prolonged the survival of mice in both syngeneic models. Mouse-specific CCL2-blockade limited A549-caused xenogeneic MPE, indicating that host-derived CCL2 also contributes to MPE precipitation in mice. The impact of CCL2/12 antagonism was associated with inhibition of immune and vascular MPE-related phenomena, such as inflammation, new blood vessel assembly and plasma extravasation into the pleural space. We conclude that CCL2 and CCL12 blockade are effective against experimental MPE induced by murine and human adenocarcinoma in mice. These results suggest that CCL2-targeted therapies may hold promise for future use against human MPE.

  14. CCL22-specific T Cells

    DEFF Research Database (Denmark)

    Martinenaite, Evelina; Munir Ahmad, Shamaila; Hansen, Morten

    2016-01-01

    Tumor cells and tumor-infiltrating macrophages produce the chemokine CCL22, which attracts regulatory T cells (Tregs) into the tumor microenvironment, decreasing anticancer immunity. Here, we investigated the possibility of targeting CCL22-expressing cells by activating specific T cells. We...... analyzed the CCL22 protein signal sequence, identifying a human leukocyte antigen A2- (HLA-A2-) restricted peptide epitope, which we then used to stimulate peripheral blood mononuclear cells (PMBCs) to expand populations of CCL22-specific T cells in vitro. T cells recognizing an epitope derived from...... the signal-peptide of CCL22 will recognize CCL22-expressing cells even though CCL22 is secreted out of the cell. CCL22-specific T cells recognized and killed CCL22-expressing cancer cells. Furthermore, CCL22-specific T cells lysed acute monocytic leukemia cells in a CCL22 expression-dependent manner. Using...

  15. Experimental approach to IGF-1 therapy in CCl4-induced acute liver damage in healthy controls and mice with partial IGF-1 deficiency.

    Science.gov (United States)

    Morales-Garza, Luis A; Puche, Juan E; Aguirre, Gabriel A; Muñoz, Úrsula; García-Magariño, Mariano; De la Garza, Rocío G; Castilla-Cortazar, Inma

    2017-05-04

    Cell necrosis, oxidative damage, and fibrogenesis are involved in cirrhosis development, a condition in which insulin-like growth factor 1 (IGF-1) levels are diminished. This study evaluates whether the exogenous administration of low doses of IGF-1 can induce hepatoprotection in acute carbon tetrachloride (CCl 4 )-induced liver damage compared to healthy controls (Wt Igf +/+ ). Additionally, the impact of IGF-1 deficiency on a damaged liver was investigated in mice with a partial deficit of this hormone (Hz Igf1 +/- ). Three groups of 25 ± 5-week-old healthy male mice (Wt Igf +/+ ) were included in the protocol: untreated controls (Wt). Controls that received CCl 4 (Wt + CCl 4 ) and Wt + CCl 4 were treated subcutaneously with IGF-1 (2 µg/100 g body weight/day) for 10 days (Wt + CCl 4  + IGF1). In parallel, three IGF-1-deficient mice (Hz Igf1 +/- ) groups were studied: untreated Hz, Hz + CCl 4 , and Hz + CCl 4  + IGF-1. Microarray and real-time quantitative polymerase chain reaction (RT-qPCR) analyses, serum aminotransferases levels, liver histology, and malondialdehyde (MDA) levels were assessed at the end of the treatment in all groups. All data represent mean ± SEM. An altered gene coding expression pattern for proteins of the extracellular matrix, fibrosis, and cellular protection were found, as compared to healthy controls, in which IGF-1 therapy normalized in the series including healthy mice. Liver histology showed that Wt + CCl 4  + IGF1 mice had less oxidative damage, fibrosis, lymphocytic infiltrate, and cellular changes when compared to the Wt + CCl 4 . Moreover, there was a correlation between MDA levels and the histological damage score (Pearson's r = 0.858). In the IGF-1-deficient mice series, similar findings were identified, denoting a much more vulnerable hepatic parenchyma. IGF1 treatment improved the biochemistry, histology, and genetic expression of pro-regenerative and cytoprotective factors in both series

  16. Attenuation of CCl4-Induced Oxidative Stress and Hepatonephrotoxicity by Saudi Sidr Honey in Rats

    Directory of Open Access Journals (Sweden)

    Mohammed Al-Yahya

    2013-01-01

    Full Text Available The present study was undertaken to investigate the possible protective effect of Saudi Sidr honey (SSH on carbon tetrachloride (CCl4 induced oxidative stress and liver and kidney damage in rat. Moreover, the antioxidant activity and the phenolic and flavonoidal contents were determined. The hepatorenal protective activity of the SSH was determined by assessing biochemical, hematological, and histological parameters. Serum transaminases, ALP, GGT, creatinine, bilirubin urea, uric acid, and MDA level in liver and kidney tissues were significantly elevated, and the antioxidant status of nonprotein sulfhydryls, albumin, and total protein levels in liver and kidney were declined significantly in CCl4 alone treated animals. Pretreatment with SSH and silymarin prior to the administration of CCl4 significantly prevented the increase of the serum levels of enzyme markers and reduced oxidative stress. SSH also exhibited a significant lipid-lowering effect and caused an HDL-C enhanced level in serum. The histopathological evaluation of the liver and kidney also revealed that honey protected incidence of both liver and kidney lesions. Moreover, SSH showed a strong antioxidant activity in DPPH and β-carotene-linoleic acid assays. SSH was found to contain phenolic compounds. Additionally, the SSH supplementation restored the hepatocytes viability against 2′,7′-dichlorofluorescein (DCF toxicity in ex vivo test.

  17. Antihepatotoxic effect of golden berry (Physalis peruviana Linn.) in carbon tetrachloride (CCl4) intoxicated rats.

    Science.gov (United States)

    Taj, Darakhshan; Khan, Hira; Sultana, Viqar; Ara, Jehan; Ehteshamul-Haque, Syed

    2014-05-01

    Liver is the main site in the body for intense metabolism and excretion. A number of chemicals and drugs which are used routinely cause liver damage. The present study investigates the antihepatotoxic effect of Physalis peruviana whole ripe fruit, water and ethanol extracts of fruit in normal as well as in carbon tetrachloride (CCl(4)) intoxicated rats. The CCl(4) treated rats showed marked elevation in liver enzymes: alanine transaminse, aspratate transaminase, alkaline phosphatase, lactate dehydrogenase and other biochemical parameters: bilirubin, creatinine and urea, thus indicating liver injury. Whereas animal treated/fed with various preparations of Physalis peruviana showed significant lowering effect (pPhysalis peruviana showed highest activity in both rat models while ripe fruit and ethanol extract showed moderate activity compared to standard drug.

  18. Effect of different levels of marigold (Calendula officinails oil extract on performance, blood parameters and immune response of broiler chickens challenged with CCl4

    Directory of Open Access Journals (Sweden)

    Reyhaneh Vahed

    2016-04-01

    Full Text Available Introduction Although use of antibiotic as growth promoter in poultry and animal nutrition have led to positive effects, researches indicated that antibiotic residues in animal and poultry products caused resistance of bacteria and fungi strains and a resistance to antibiotics as a treatment tool for human diseases. Herbal extracts, probiotics and enzymes are suggested as replacers for antibiotics in animal and poultry nutrition. Plants and their active substances with their variety of functions are used as medicinal plants for years to prevent and treat many diseases in human, animal and poultry. Oil extracts of marigold has many active substances such as saponins, flavonoids and antioxidants and serve as a strong antioxidant to control free radicals. Therefore, the extract of marigold was used to test its curing effects on challenged birds with tetra hydrochloride (CCl4, an inducer for liver damage. Material and methods This experiment was conducted to evaluate the effects of marigold oil extracts (MOE on performance, blood parameters and immune response of broiler chickens in a 42-day period. A total of 200 Ross 308 male broiler chickens were allocated to five dietary treatments with four replicates of 10 birds each. Treatments consisted of 1 control (without marigold extract and CCl4, 2 CCl4, 3-5 150, 300, and 450 mg/kg marigold oil extract as supplement + CCl4 (1 mg/kg body weight. CCl4 was injected intraperitoneally from 21 to 30 days of age in a 2- day intervals. During this period sodium chloride (0.9% was added to control group. At day 33, one chick from each replicate of treatments was selected, and their blood and internal organs were used for different bio assays. Results and Discussion No significant differences detected among treatments for performance. However, the highest and the lowest feed intake at starter and grower periods obtained from the treatments used MOE and control groups, respectively (table 2. The highest and the

  19. Hepatoprotective and antioxidant effects of single clove garlic against CCl4-induced hepatic damage in rabbits.

    Science.gov (United States)

    Naji, Khalid Mohammed; Al-Shaibani, Elham Shukri; Alhadi, Fatima A; Al-Soudi, Safa'a Abdulrzaq; D'souza, Myrene R

    2017-08-17

    The increase in demand and consumption of single clove garlic or 'Solo garlic' (Allium sativum) has resulted in an increase in research on its therapeutic properties. The present study aims to evaluate the antioxidant activities, oxidant-scavenging efficiency and preventive effects of SCG (single clove garlic) and MCG (multi clove garlic) on CCl 4 -induced acute hepatotoxicity in male rabbits. For this purpose, rabbits were orally administered with 3 ml of CCl 4 /kg of body weight, followed by 0.8 g of MCG or SCG/kg twice a week for three successive weeks. Oxidative hepatotoxicity was then assessed. SCG extracts exhibited higher antioxidant capacity than the MCG extract. Scavenging ability of SCG showed significant (p garlic storage constituents varies with the number of cloves present. CCl 4 -induced hepatotoxicity demonstrated histological changes including severe damage in the structure of liver tissues which correlated well to oxidative stress levels. Simultaneously, administration of SCG resulted in a significant reduction of serum alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and total bilirubin (TB) levels in addition to improvement in some histological parameters. Low levels of lipid peroxidation (malondialdehyde, MDA) (p < 0.001), along with a huge reduction in peroxidase (POx) (p < 0.001) revealed protection against oxidative toxicity in the liver homogenate. Higher levels of catalase (CAT) (p < 0.001) and superoxide dismutase (SOD) (p < 0.05) when compared to the MCG test (TM) group indicates that removal of H 2 O 2 is based on CAT activity in SCG test (TS) group rather than the POx activity demonstrated in the former group. The present study indicates that SCG possesses more protective ability than MCG against CCl 4 -induced liver injury and might be an effective alternative medicine against acute oxidative liver toxicity.

  20. KNOWLEDGE AND MISCONCEPTIONS OF PULMONARY TUBERCULOSIS PATIENTS AT DOTS CENTRE, URBAN MEERUT.

    Directory of Open Access Journals (Sweden)

    R Bansal

    2013-06-01

    Full Text Available Background: India is the second most populated country in the world; it has more new TB cases annually than any other country. In 2008, 1.98 million were estimated to have occurred in India, of whom 0.87 million were infectious cases, thus amounting to a fifth of the global burden of TB.With the entire country geographically covered under the DOTS program, research into socioeconomic impact of TB on patients and their households is crucial for providing comprehensive patient-friendly TB services and to document the benefits of DOTS. Objective: The present study was undertaken with the following objectives: (1 To determine the socio-demographic variables of registered patients for DOTS Treatment at Urban Health Training center Meerut. (2 To assess knowledge, awareness and attitude regarding Pulmonary Tuberculosis and its treatment among the patients. Materials and Methods: A cross-sectional study of 200 TB patients was done using a pre-tested semi-quantitative questionnaire in UHTC Meerut Period of Study: During 2010-2012. Results: Knowledge and awareness regarding Pulmonary Tuberculosis in patients at DOTS centre, Urban Meerut was very poor. There is a great need to educate the people about misconceptions like food and utensils as mode of transmission. BCC using the person to person contact in community , at health center and awareness campaigns are crucial in educating the ignorance seen in our field practice area. Conclusion: Poor knowledge and misconceptions concerning tuberculosis was quite concern in the patients. TB control program will remain ineffective unless myths and fears of TB patients are addressed related to causation of tuberculosis, mode of spread, and methods of prevention.

  1. KNOWLEDGE AND MISCONCEPTIONS OF PULMONARY TUBERCULOSIS PATIENTS AT DOTS CENTRE, URBAN MEERUT.

    Directory of Open Access Journals (Sweden)

    R Bansal

    2013-08-01

    Full Text Available Background: India is the second most populated country in the world; it has more new TB cases annually than any other country. In 2008, 1.98 million were estimated to have occurred in India, of whom 0.87 million were infectious cases, thus amounting to a fifth of the global burden of TB.With the entire country geographically covered under the DOTS program, research into socioeconomic impact of TB on patients and their households is crucial for providing comprehensive patient-friendly TB services and to document the benefits of DOTS. Objective: The present study was undertaken with the following objectives: (1 To determine the socio-demographic variables of registered patients for DOTS Treatment at Urban Health Training center Meerut. (2 To assess knowledge, awareness and attitude regarding Pulmonary Tuberculosis and its treatment among the patients. Materials and Methods: A cross-sectional study of 200 TB patients was done using a pre-tested semi-quantitative questionnaire in UHTC Meerut Period of Study: During 2010-2012. Results: Knowledge and awareness regarding Pulmonary Tuberculosis in patients at DOTS centre, Urban Meerut was very poor. There is a great need to educate the people about misconceptions like food and utensils as mode of transmission. BCC using the person to person contact in community , at health center and awareness campaigns are crucial in educating the ignorance seen in our field practice area. Conclusion: Poor knowledge and misconceptions concerning tuberculosis was quite concern in the patients. TB control program will remain ineffective unless myths and fears of TB patients are addressed related to causation of tuberculosis, mode of spread, and methods of prevention.

  2. Oligonol Ameliorates CCl4-Induced Liver Injury in Rats via the NF-Kappa B and MAPK Signaling Pathways

    Directory of Open Access Journals (Sweden)

    Jeonghyeon Bak

    2016-01-01

    Full Text Available Oxidative stress is thought to be a key risk factor in the development of hepatic diseases. Blocking or retarding the reactions of oxidation and the inflammatory process by antioxidants could be a promising therapeutic intervention for prevention or treatment of liver injuries. Oligonol is a low molecular weight polyphenol containing catechin-type monomers and oligomers derived from lychee fruit. In this study, we investigated the anti-inflammatory effect of oligonol on carbon tetrachloride- (CCl4- induced acute hepatic injury in rats. Oral administration of oligonol (10 or 50 mg/kg reduced CCl4-induced abnormalities in liver histology and serum AST and serum ALT levels. Oligonol treatment attenuated the CCl4-induced production of inflammatory mediators, including TNF-α, IL-1β, cyclooxygenase-2 (COX-2, and inducible nitric oxide synthase (iNOS mRNA levels. Western blot analysis showed that oligonol suppressed proinflammatory nuclear factor-kappa B (NF-κB p65 activation, phosphorylation of extracellular signal-regulated kinase (ERK, c-Jun NH2-terminal kinase (JNK, and p38 mitogen-activated protein kinases (MAPKs as well as Akt. Oligonol exhibited strong antioxidative activity in vitro and in vivo, and hepatoprotective activity against t-butyl hydroperoxide-induced HepG2 cells. Taken together, oligonol showed antioxidative and anti-inflammatory effects in CCl4-intoxicated rats by inhibiting oxidative stress and NF-κB activation via blockade of the activation of upstream kinases including MAPKs and Akt.

  3. Preparation of ThO2 sols suitable for gelation into microspheres in CCl4-ammonia media

    International Nuclear Information System (INIS)

    Yamagishi, Shigeru; Takahashi, Yoshihisa

    1985-01-01

    Production conditions of ThO 2 sols are studied for satisfactorily gelling them into microspheres in CCl 4 -ammonia media, which result gel-spheres with good sphericities but need high-quality source-sols for crackfree gelation. Two-stage pH-setting techniques were added to the previously reported method, which had been developed to produce ThO 2 sols suitable for gelation in hexone-ammonia media and was characterized by preneutralization followed by neutralization under pH-control. As a result, colloid fractions of Th in sols were increased without decreasing colloid size. This enabled one to obtain crackfree, large, spherical ThO 2 particles by gelation in the CCl 4 -ammonia media. (author)

  4. Intrinsic renal cells induce lymphocytosis of Th22 cells from IgA nephropathy patients through B7-CTLA-4 and CCL-CCR pathways.

    Science.gov (United States)

    Gan, Lu; Zhou, Qiaoling; Li, Xiaozhao; Chen, Chen; Meng, Ting; Pu, Jiaxi; Zhu, Mengyuan; Xiao, Chenggen

    2018-04-01

    IgA nephropathy (IgAN), the most common glomerulonephritis, has an unclear pathogenesis. The role of Th22 cells, which are intimately related to proteinuria and progression in IgAN, in mediating infection-related IgAN is unclear. This study aimed to characterize the association between intrinsic renal cells (tubular epithelial cells and mesangial cells) and Th22 cells in immune regulation of infection-related IgAN and to elucidate the impact of Th22 lymphocytosis; the proinflammatory cytokines IL-1, IL-6, and TNF-α; and CCL chemokines on kidney fibrosis. Hemolytic streptococcus infection induced an increase in IL-1, IL-6, and TNF-α, resulting in Th22 cell differentiation from T lymphocytes obtained from patients with IgAN, and the CCL20-CCR6, CCL22-CCR4, and/or CCL27-CCR10 axes facilitated Th22 cell chemotaxis. The increased amount of Th22 cells caused an increase in TGF-β1 levels, and anti-CD80, anti-CD86, and CTLA-4Ig treatment reduced TGF-β1 levels by inhibiting Th22 lymphocytosis and secretion of cytokines and chemokines, thus potentially relieving kidney fibrosis. Our data suggest that Th22 cells might be recruited into the kidneys via the CCL20-CCR6, CCL22-CCR4, and/or CCL27-CCR10 axes by mesangial cells and tubular epithelial cells in infection-related IgAN. Th22 cell overrepresentation was attributed to stimulation of the B7-CTLA-4Ig antigen-presenting pathway and IL-1, IL-6, and TNF-α.

  5. Protective effect of Sida cordata leaf extract against CCl(4) induced acute liver toxicity in rats.

    Science.gov (United States)

    Mistry, Sunil; Dutt, K R; Jena, J

    2013-04-13

    To investigate the hepatoprotective potential of Sida cordata (Malvaceae) (S. cordata) in experimental rats to validate its traditional claim. Wister albino rats were divided into 6 groups: Group I served as control; Group II served as hepatotoxic (CCl(4) treated) group; Group III, IV and V served as (100, 200 and 400 mg/kg b.w.) S. cordata leaf extract (SCLE) treated groups; Group VI served as positive control (Silymarin) treated group. Liver marker enzymes serum glutamate oxyloacetic transaminase, serum glutamic pyruvic transaminase, pancreatic enzymatic antioxidants superoxide dismutase (SOD), lipid peroxidation, catalase (CAT), reduced glutathione (GSH) were measured and compared along with histopathological studies. Obtained results show that the treatment with SCLE significantly (P<0.05-<0.001) and dose-dependently reduced CCl4 induced elevated serum level of hepatic enzymes. Furthermore, SCLE significantly (up to P<0.001) reduced the lipid peroxidation in the liver tissue and restored activities of defence antioxidant enzymes GSH, SOD and CAT towards normal levels, which was confirmed by the histopathological studies. The results of this study strongly indicate the protective effect of SCLE against CCl(4) induced acute liver toxicity in rats and thereby scientifically support its traditional use. Copyright © 2013 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  6. CCl 4 chemistry on the reduced selvedge of a α-Fe 2O 3(0 0 0 1) surface: a scanning tunneling microscopy study

    Science.gov (United States)

    Rim, Kwang Taeg; Fitts, Jeffrey P.; Müller, Thomas; Adib, Kaveh; Camillone, Nicholas; Osgood, Richard M.; Joyce, S. A.; Flynn, George W.

    2003-09-01

    Scanning tunneling microscopy (STM) and low energy electron diffraction (LEED) were used to study the degradation of CCl 4 on the reduced selvedge of a natural single crystal α-Fe 2O 3(0 0 0 1) surface in ultrahigh vacuum. Before exposure to CCl 4, STM images indicate that approximately 85% of the reduced surface exhibits a Fe 3O 4(1 1 1) 2 × 2 termination, while the remaining 15% is terminated by 1 × 1 and superstructure phases. Images obtained after room temperature dosing with CCl 4 and subsequent flashing to 600 K reveal that chlorine atoms are adsorbed only on surface regions with the Fe 3O 4(1 1 1) 2 × 2 termination, not on 1 × 1 and superstructure regions. Chlorine atoms from dissociative adsorption of CCl 4 are observed to occupy two distinct positions located atop lattice protrusions and in threefold oxygen vacancy sites. However, in companion chemical labeling experiments, chlorine atoms provided by room temperature, dissociative Cl 2 adsorption on this surface are found to occupy sites atop lattice protrusions exclusively. The clear dissimilarity in STM feature shape and brightness at the two distinct chlorine adsorption sites arising from CCl 4 dissociation as well as the results of the Cl 2 chemical labeling experiments are best explained via reactions on a Fe 3O 4(1 1 1) 2 × 2 selvedge terminated by a 1/4 monolayer of tetrahedrally coordinated iron atoms. On this surface, adsorption atop an iron atom occurs for both the CCl 4 and Cl 2 dissociative reactions. A second adsorption site, assigned as binding to second layer iron atoms left exposed following surface oxygen atom abstraction resulting in the formation of phosgene (COCl 2), only appears in the case of reaction with CCl 4. The reaction mechanism and active site requirements for CCl 4 degradation on iron oxide surfaces are discussed in light of this evidence and in the context of our previously reported results from Auger electron spectroscopy (AES), LEED, temperature-programmed desorption

  7. Hepatoprotective potential of antioxidant potent fraction from Urtica dioica Linn. (whole plant in CCl4 challenged rats

    Directory of Open Access Journals (Sweden)

    Bhuwan Chandra Joshi

    2015-01-01

    Full Text Available The aim of the present study was to isolate hepatoprotective component from Urtica dioica Linn. (whole plant against CCl4-induced hepatotoxicity in-vitro (HepG2 cells and in-vivo (rats model. Antioxidant activity of hydro alcoholic extract and its fractions petroleum ether fraction (PEF, ethyl acetate fraction (EAF, n-butanol fraction (NBF and aqueous fraction (AF were determined by DPPH and NO radicals scavenging assay. Fractions were subjected to in-vitro HepG2 cell line study. Further, the most potent fraction (EAF was subjected to in-vivo hepatoprotective potential against CCl4 challenged rats. The in-vivo hepatoprotective active fraction was chromatographed on silica column to isolate the bioactive constituent(s. Structure elucidation was done by using various spectrophotometric techniques like UV, IR, 1H NMR, 13C NMR and MS spectroscopy. Ethyl acetate fraction (EAF of hydro-alcoholic extract of U. dioica possessed the potent antioxidant activity viz. DPPH (IC50 78.99 ± 0.17 μg/ml and NO (IC50101.39 ± 0.30 μg/ml. The in-vitro HepG2 cell line study showed that the EAF prevented the cell damage. The EAF significantly attenuated the increased liver enzymes activities in serum and oxidative parameters in tissue of CCl4-induced rats, suggesting hepatoprotective and anti-oxidant action respectively. Column chromatography of most potent antioxidant fraction (EAF lead to the isolation of 4-hydroxy-3-methoxy cinnamic acid (ferulic acid which is responsible for its hepatoprotective potential. Hence, the present study suggests that EAF of hydro-alcoholic extract has significant antioxidant and hepatoprotective potential on CCl4 induced hepatotoxicity in-vitro and in-vivo.

  8. Hepatoprotective potential of antioxidant potent fraction from Urtica dioica Linn. (whole plant) in CCl4 challenged rats.

    Science.gov (United States)

    Joshi, Bhuwan Chandra; Prakash, Atish; Kalia, Ajudhia N

    2015-01-01

    The aim of the present study was to isolate hepatoprotective component from Urtica dioica Linn. (whole plant) against CCl 4 -induced hepatotoxicity in-vitro (HepG2 cells) and in-vivo (rats) model. Antioxidant activity of hydro alcoholic extract and its fractions petroleum ether fraction (PEF), ethyl acetate fraction (EAF), n -butanol fraction (NBF) and aqueous fraction (AF) were determined by DPPH and NO radicals scavenging assay. Fractions were subjected to in-vitro HepG2 cell line study. Further, the most potent fraction (EAF) was subjected to in-vivo hepatoprotective potential against CCl 4 challenged rats. The in-vivo hepatoprotective active fraction was chromatographed on silica column to isolate the bioactive constituent(s). Structure elucidation was done by using various spectrophotometric techniques like UV, IR, 1 H NMR, 13 C NMR and MS spectroscopy. Ethyl acetate fraction (EAF) of hydro-alcoholic extract of U. dioica possessed the potent antioxidant activity viz. DPPH (IC 50 78.99 ± 0.17 μg/ml) and NO (IC 50 101.39 ± 0.30 μg/ml). The in-vitro HepG2 cell line study showed that the EAF prevented the cell damage. The EAF significantly attenuated the increased liver enzymes activities in serum and oxidative parameters in tissue of CCl 4 -induced rats, suggesting hepatoprotective and anti-oxidant action respectively. Column chromatography of most potent antioxidant fraction (EAF) lead to the isolation of 4-hydroxy-3-methoxy cinnamic acid (ferulic acid) which is responsible for its hepatoprotective potential. Hence, the present study suggests that EAF of hydro-alcoholic extract has significant antioxidant and hepatoprotective potential on CCl 4 induced hepatotoxicity in-vitro and in-vivo .

  9. Supplementation of Citrus maxima Peel Powder Prevented Oxidative Stress, Fibrosis, and Hepatic Damage in Carbon Tetrachloride (CCl4) Treated Rats.

    Science.gov (United States)

    Chowdhury, Mohammed Riaz Hasan; Sagor, Md Abu Taher; Tabassum, Nabila; Potol, Md Abdullah; Hossain, Hemayet; Alam, Md Ashraful

    2015-01-01

    Citrus maxima peel is rich in natural phenolic compounds and has a long use in the traditional medicine. HPLC-DAD analysis on Citrus maxima peel powder exhibited the presence of various phenolic compounds such as caffeic acid and (-)-epicatechin. To determine the plausible hepatoprotective activity of Citrus maxima peel powder, we used carbon tetrachloride (CCl4) treated rat model. Liver damage in rats was confirmed by measuring the AST, ALT, and ALP enzyme activities. In addition, lipid peroxidation products (MDA), nitric oxide, advanced protein oxidation products level (APOP), and catalase activities were also analyzed along with the histological profiling for the inflammatory cell infiltration, collagen, and iron deposition in liver. Dietary supplementation of Citrus maxima peel powder exhibited significant reduction of serum AST, ALT, and ALP activities in carbon tetrachloride treated rats. Moreover, Citrus maxima peel powder also showed a significant reduction of the oxidative stress markers (MDA, NO, and APOP level) and restored the catalase activity in CCl4 treated rats. Histological examination of the liver section revealed reduced inflammatory cells infiltration, collagen, and iron deposition in CCl4 treated rats. The results from this study demonstrated that Citrus maxima peel powder produced significant hepatoprotective action in CCl4 administered rats.

  10. Supplementation of Citrus maxima Peel Powder Prevented Oxidative Stress, Fibrosis, and Hepatic Damage in Carbon Tetrachloride (CCl4 Treated Rats

    Directory of Open Access Journals (Sweden)

    Mohammed Riaz Hasan Chowdhury

    2015-01-01

    Full Text Available Citrus maxima peel is rich in natural phenolic compounds and has a long use in the traditional medicine. HPLC-DAD analysis on Citrus maxima peel powder exhibited the presence of various phenolic compounds such as caffeic acid and (−-epicatechin. To determine the plausible hepatoprotective activity of Citrus maxima peel powder, we used carbon tetrachloride (CCl4 treated rat model. Liver damage in rats was confirmed by measuring the AST, ALT, and ALP enzyme activities. In addition, lipid peroxidation products (MDA, nitric oxide, advanced protein oxidation products level (APOP, and catalase activities were also analyzed along with the histological profiling for the inflammatory cell infiltration, collagen, and iron deposition in liver. Dietary supplementation of Citrus maxima peel powder exhibited significant reduction of serum AST, ALT, and ALP activities in carbon tetrachloride treated rats. Moreover, Citrus maxima peel powder also showed a significant reduction of the oxidative stress markers (MDA, NO, and APOP level and restored the catalase activity in CCl4 treated rats. Histological examination of the liver section revealed reduced inflammatory cells infiltration, collagen, and iron deposition in CCl4 treated rats. The results from this study demonstrated that Citrus maxima peel powder produced significant hepatoprotective action in CCl4 administered rats.

  11. Preliminary report on electron energy-loss measurements for CCl3, CCl2F2, CCl3F

    International Nuclear Information System (INIS)

    Bushnell, D.L. Jr.; Huebner, R.H.; Celotta, R.J.; Mielczarek, S.R.

    1975-01-01

    Currently, nation-wide research efforts are devoted to studying the possible ozone (O 3 ) depletion in the stratosphere by the chemical action of chlorine atoms released from CCl 2 F 2 or CCl 3 F upon absorption of ultraviolet radiation. Since electron-impact data taken in the forward scattering direction can be used to derive oscillator strengths and thus to yield apparent photoabsorption cross sections, such an analysis for CCl 2 F 2 , CCLl 3 F, and CClF 3 was carried out. Oscillator-strength distributions were obtained between 5 and 20 eV and are compared to available photoabsorption data. Certain photoabsorption values agree very well with these electron-impact data, but other optical studies deviate in some spectral regions by as much as a factor of 5. Also, the electron energy-loss spectrum reveals electronic transitions previously undetected by photoabsorption

  12. UV Absorption Cross Sections of Nitrous Oxide (N2O) and Carbon Tetrachloride (CCl4) Between 210 and 350 K and the Atmospheric Implications

    Science.gov (United States)

    Carlon, Nabilah Rontu; Papanastasiou, Dimitrios K.; Fleming, Eric L.; Jackman, Charles H.; Newman, Paul A.; Burkholder, James B.

    2010-01-01

    Absorption cross sections of nitrous oxide (N2O) and carbon tetrachloride (CCl4) are reported at five atomic UV lines (184.95, 202.548, 206.200, 213.857, and 228.8 nm) at 27 temperatures in the range 210-350 K. In addition, UV absorption spectra of CCl4 are reported between 200-235 nm as a function of temperature (225-350 K). The results from this work are critically compared with results from earlier studies. For N2O, the present results are in good agreement with the current JPL recommendation enabling a reduction in the estimated uncertainty in the N2O atmospheric photolysis rate. For CCl4, the present cross section results are systematically greater than the current recommendation at the reduced temperatures most relevant to stratospheric photolysis. The new cross sections result in a 5-7% increase in the modeled CCl4 photolysis loss, and a slight decrease in the stratospheric lifetime, from 51 to 50 years, for present day conditions. The corresponding changes in modeled inorganic chlorine and ozone in the stratosphere are quite small. A CCl4 cross section parameterization for use in 37 atmospheric model calculations is presented.

  13. UV and infrared absorption spectra, atmospheric lifetimes, and ozone depletion and global warming potentials for CCl2FCCl2F (CFC-112, CCl3CClF2 (CFC-112a, CCl3CF3 (CFC-113a, and CCl2FCF3 (CFC-114a

    Directory of Open Access Journals (Sweden)

    M. E. Davis

    2016-07-01

    Full Text Available The potential impact of CCl2FCF3 (CFC-114a and the recently observed CCl2FCCl2F (CFC-112, CCl3CClF2 (CFC-112a, and CCl3CF3 (CFC-113a chlorofluorocarbons (CFCs on stratospheric ozone and climate is presently not well characterized. In this study, the UV absorption spectra of these CFCs were measured between 192.5 and 235 nm over the temperature range 207–323 K. Precise parameterizations of the UV absorption spectra are presented. A 2-D atmospheric model was used to evaluate the CFC atmospheric loss processes, lifetimes, ozone depletion potentials (ODPs, and the associated uncertainty ranges in these metrics due to the kinetic and photochemical uncertainty. The CFCs are primarily removed in the stratosphere by short-wavelength UV photolysis with calculated global annually averaged steady-state lifetimes (years of 63.6 (61.9–64.7, 51.5 (50.0–52.6, 55.4 (54.3–56.3, and 105.3 (102.9–107.4 for CFC-112, CFC-112a, CFC-113a, and CFC-114a, respectively. The range of lifetimes given in parentheses is due to the 2σ uncertainty in the UV absorption spectra and O(1D rate coefficients included in the model calculations. The 2-D model was also used to calculate the CFC ozone depletion potentials (ODPs with values of 0.98, 0.86, 0.73, and 0.72 obtained for CFC-112, CFC-112a, CFC-113a, and CFC-114a, respectively. Using the infrared absorption spectra and lifetimes determined in this work, the CFC global warming potentials (GWPs were estimated to be 4260 (CFC-112, 3330 (CFC-112a, 3650 (CFC-113a, and 6510 (CFC-114a for the 100-year time horizon.

  14. The protective effect of ENA Actimineral resource A on CCl4-induced liver injury in rats.

    Science.gov (United States)

    Hong, Il-Hwa; Ji, Hoon; Hwa, Sung-Yong; Jeong, Won-Il; Jeong, Da-Hee; Do, Sun-Hee; Kim, Ji-Min; Ki, Mi-Ran; Park, Jin-Kyu; Goo, Moon-Jung; Hwang, Ok-Kyung; Hong, Kyung-Sook; Han, Jung-Youn; Chung, Hae-Young; Jeong, Kyu-Shik

    2011-06-01

    ENA Actimineral Resource A (ENA-A) is alkaline water that is composed of refined edible cuttlefish bone and two different species of seaweed, Phymatolithon calcareum and Lithothamnion corallioides. In the present study, ENA-A was investigated as an antioxidant to protect against CCl(4)-induced oxidative stress and hepatotoxicity in rats. Liver injury was induced by either subacute or chronic CCl(4) administration, and the rats had free access to tap water mixed with 0% (control group) or 10% (v/v) ENA-A for 5 or 8 weeks. The results of histological examination and measurement of antioxidant activity showed that the reactive oxygen species production, lipid peroxidation, induction of CYP2E1 were decreased and the antioxidant activity, including glutathione and catalase production, was increased in the ENA-A groups as compared with the control group. On 2-DE gel analysis of the proteomes, 13 differentially expressed proteins were obtained in the ENA-A groups as compared with the control group. Antioxidant proteins, including glutathione S-transferase, kelch-like ECH-associated protein 1, and peroxiredoxin 1, were increased with hepatocyte nuclear factor 3-beta and serum albumin precursor, and kininogen precursor decreased more in the ENA-A groups than compared to the control group. In conclusion, our results suggest that ENA-A does indeed have some protective capabilities against CCl(4)-induced liver injury through its antioxidant function.

  15. Nanodiamond-based nanostructures for coupling nitrogen-vacancy centres to metal nanoparticles and semiconductor quantum dots.

    Science.gov (United States)

    Gong, Jianxiao; Steinsultz, Nat; Ouyang, Min

    2016-06-08

    The ability to control the interaction between nitrogen-vacancy centres in diamond and photonic and/or broadband plasmonic nanostructures is crucial for the development of solid-state quantum devices with optimum performance. However, existing methods typically employ top-down fabrication, which restrict scalable and feasible manipulation of nitrogen-vacancy centres. Here, we develop a general bottom-up approach to fabricate an emerging class of freestanding nanodiamond-based hybrid nanostructures with external functional units of either plasmonic nanoparticles or excitonic quantum dots. Precise control of the structural parameters (including size, composition, coverage and spacing of the external functional units) is achieved, representing a pre-requisite for exploring the underlying physics. Fine tuning of the emission characteristics through structural regulation is demonstrated by performing single-particle optical studies. This study opens a rich toolbox to tailor properties of quantum emitters, which can facilitate design guidelines for devices based on nitrogen-vacancy centres that use these freestanding hybrid nanostructures as building blocks.

  16. Spontaneous polarization and pyroelectric effect in improper ferroelectrics-ferroelastics Gd2(MoO4)3 and Tb2(MoO4)3 at low temperature

    International Nuclear Information System (INIS)

    Matyjasik, S; Shaldin, Yu.V.

    2013-01-01

    Experimental dependencies for spontaneous polarization ΔP s (T) and pyroelectric coefficient γ s (T)for Gd 2 (MoO 4 ) 3 (GMO) and Tb 2 (MoO 4 ) 3 (TMO) reported here differs from those for intrinsic ferroelectrics. We found fundamental distinction in GMO and TMO samples behavior at their repolarization at the fixed temperatures 300 and 4.2 K. In TMO monodomainization temperature does not affect experimental data, while in GMO monodomainization at 4.2 K results in increase of ΔP s (T) by order of magnitude at 85 K and γ s (T) dependence shows well-defined anomalies, reaching a record magnitude of 3 centre dot 10 -4 C/(m 2 centre dot K) at T = 25 K. At T = 200 K the pyroelectric coefficients values are -1.45 centre dot 10 -6 C/(m 2 centre dot K) and-1.8 centre dot 10 -6 C/(m 2 centre dot K). Taking into account our data, results related to transformation of structure in (001) plane and symmetry reasons we suggested crystallographic model of GMO type improper ferroelectric. It is formed by four meso-tetrahedrons constructed of three coordination tetrahedrons MO 4 (a, b and c types). In the framework of this model we discuss the physical meaning of pseudodeviator Q 12 *, coefficient, that initiate the phase transition at T > 433 K from noncentrosymmetric phase (mm2) to another one (4-bar2m).

  17. Dissociative adsorption of CCl 4 on the Fe 3O 4(1 1 1)-(2×2) selvedge of α-Fe 2O 3(0 0 0 1)

    Science.gov (United States)

    Adib, K.; Mullins, D. R.; Totir, G.; Camillone, N.; Fitts, J. P.; Rim, K. T.; Flynn, G. W.; Osgood, R. M.

    2003-02-01

    The surface reactions of CCl 4 with the Fe 3O 4(1 1 1)-(2×2) selvedge of naturally occurring α-Fe 2O 3(0 0 0 1) single-crystals have been investigated using synchrotron X-ray photoelectron spectroscopy (XPS) and temperature-programmed desorption (TPD). CCl 4 was found to dissociate on the Fe 3O 4 surface at 100 K producing chemisorbed Cl and adsorbed CCl 2. TPD shows that the large majority of the dissociatively adsorbed CCl 2 fragments extract lattice oxygen and desorb as phosgene at >275 K. However, the XPS spectra show no evidence for the formation of surface-bound phosgene, at 100 K, indicating that its formation involves two steps. The first step, dissociation, is spontaneous at 100 K, whereas the second, oxygen atom abstraction to form phosgene, requires thermal excitation. Cl chemisorption yielded two separate species, the mono- and dichloride terminations of surface iron sites. The identification of these two surface terminations is based on the coverage dependence and the surface temperature history of their Cl 2p 3/2 peak intensity. For example, heating to >450 K allows the monochloride to transform into iron dichloride, indicating Cl adatom mobility at these temperatures.

  18. Profile of circulating levels of IL-1Ra, CXCL10/IP-10, CCL4/MIP-1β and CCL2/MCP-1 in dengue fever and parvovirosis

    Directory of Open Access Journals (Sweden)

    Luzia Maria de-Oliveira-Pinto

    2012-02-01

    Full Text Available Dengue virus (DENV and parvovirus B19 (B19V infections are acute exanthematic febrile illnesses that are not easily differentiated on clinical grounds and affect the paediatric population. Patients with these acute exanthematic diseases were studied. Fever was more frequent in DENV than in B19V-infected patients. Arthritis/arthralgias with DENV infection were shown to be significantly more frequent in adults than in children. The circulating levels of interleukin (IL-1 receptor antagonist (Ra, CXCL10/inducible protein-10 (IP-10, CCL4/macrophage inflammatory protein-1 beta and CCL2/monocyte chemotactic protein-1 (MCP-1 were determined by multiplex immunoassay in serum samples obtained from B19V (37 and DENV-infected (36 patients and from healthy individuals (7. Forward stepwise logistic regression analysis revealed that circulating CXCL10/IP-10 tends to be associated with DENV infection and that IL-1Ra was significantly associated with DENV infection. Similar analysis showed that circulating CCL2/MCP-1 tends to be associated with B19V infection. In dengue fever, increased circulating IL-1Ra may exert antipyretic actions in an effort to counteract the already increased concentrations of IL-1β, while CXCL10/IP-10 was confirmed as a strong pro-inflammatory marker. Recruitment of monocytes/macrophages and upregulation of the humoral immune response by CCL2/MCP-1 by B19V may be involved in the persistence of the infection. Children with B19V or DENV infections had levels of these cytokines similar to those of adult patients.

  19. ESR investigation of the reactions of glutathione, cysteine and penicillamine thiyl radicals: competitive formation of RSOcenter dot, Rcenter dot, RSSRcenter dot-. , and RSScenter dot

    Energy Technology Data Exchange (ETDEWEB)

    Becker, David; Swarts, Steven; Champagne, Mark; Sevilla, M D

    1988-05-01

    The reactions of cysteine, glutathione and penicillamine thiyl radicals with oxygen and their parent thiols in frozen solutions have been elucidated with e.s.r. The major sulfur radicals observed are: (1) thiyl radicals, RS center dot; (2) disulfide radical anions, RSSR anion radicals; (3) perthiyl radicals, RSS center dot and upon introduction of oxygen; (4) sulfinyl radicals, RSO center dot, where R represents the remainder of the cysteine, glutathione or penicillamine moiety. The radical product observed depends on pH, concentration of thiol, and presence or absence of molecular oxygen. The sulfinyl radical is a ubiquitous intermediate, peroxyl radical attack on thiols may lead to sulfinyl radicals. The authors elaborate the observed reaction sequences that lead to sulfinyl radicals and, using /sup 17/O isotopic substitution studies, demonstrate the oxygen atom in sulfinyl radicals originates from dissolved molecular oxygen. The glutathione radical is found to abstract hydrogen from the ..cap alpha..-carbon position on the cysteine residue of glutathione to form a carbon-centred radical.

  20. Flavonoid constituents of Dobera glabra leaves: amelioration impact against CCl4-induced changes in the genetic materials in male rats.

    Science.gov (United States)

    Elkhateeb, Ahmed; Abdel Latif, Rasha R; Marzouk, Mona M; Hussein, Sameh R; Kassem, Mona E S; Khalil, Wagdy K B; El-Ansari, Mohamed A

    2017-12-01

    Dobera glabra (Forssk.) Poir (Salvadoraceae) is a highly valued tree with diverse importance as special mineral sourced feed and a folkloric tool for forecasting droughts. However, there are no reports on its phytochemical and biological investigations. Phytochemical investigation of D. glabra leaves and its protective potential against CCl 4 inducing changes in the genetic materials. D. glabra extract, DGE (70% MeOH/H 2 O), was applied to polyamide column chromatography, eluting with MeOH/H 2 O of decreasing polarities, followed by preparative chromatographic tools, yielded seven compounds. Three DGE doses (50, 100 and 200 mg/kg bw/d) were administrated for 8 weeks intragastrically to male albino rats prior treated with CCl 4 (0.5 mL/kg/bw). The reactive oxygen species (ROS) levels, expression changes of glutamate transporters (GLAST, GLT-1 and SNAT3) mRNA, DNA fragmentation and glutathione peroxidase (GPx) activity were investigated in the liver tissues of these rats. Isorhamnetin-3-O-β-glucopyranoside-7-O-α-rhamnopyranoside, isorhamnetin-3-O-α-rhamnopyranoside-7-O-β-glucopyranoside, kaempferol-3,7-di-O-α-rhamnopyranoside, isorhamnetin-3-O-β-glucopyranoside, kaempferol-3-O-β-glucopyranoside, isorhamnetin and kaempferol were identified. DGE (200 mg/kg bw) + CCl 4 exhibited the most significant reduction in ROS levels and DNA fragmentation with 251.3% and141% compared to 523.1% and 273.2% for CCl 4 , respectively. Additionally, it increased significantly the mRNA expression of GLAST, GLT-1 and SNAT3 to 2.16-, 1.72- and 2.09-fold, respectively. Also, GPx activity was increased to 4.8 U/mg protein/min compared to CCl 4 (1.8 U/mg protein/min). Flavonoid constituents, antioxidant effect and genotoxic protection activity of D. glabra were first reported. DGE may be valuable in the treatment and hindrance of hepatic oxidative stress and genotoxicity.

  1. CH_3Cl, CH_2Cl_2, CHCl_3, and CCl_4: Infrared spectra, radiative efficiencies, and global warming potentials

    International Nuclear Information System (INIS)

    Wallington, Timothy J.; Pivesso, Bruno Pasquini; Lira, Alane Moura; Anderson, James E.; Nielsen, Claus Jørgen; Andersen, Niels Højmark; Hodnebrog, Øivind

    2016-01-01

    Infrared spectra for the title compounds were measured experimentally in 700 Torr of air at 295 K and systematically modeled in B3LYP, M06-2X and MP2 calculations employing various basis sets. Calibrated infrared spectra over the wavenumber range 600–3500 cm"−"1 are reported and combined with literature data to provide spectra for use in experimental studies and radiative transfer calculations. Integrated absorption cross sections are (units of cm"−"1 molecule"−"1): CH_3Cl, 660–780 cm"−"1, (3.89±0.19)×10"−"1"8; CH_2Cl_2, 650–800 cm"−"1, (2.16±0.11)×10"−"1"7; CHCl_3, 720–810 cm"−"1, (4.08±0.20)×10"−"1"7; and CCl_4, 730–825 cm"−"1, (6.30±0.31)×10"−"1"7. CH_3Cl, CH_2Cl_2, CHCl_3, and CCl_4 have radiative efficiencies of 0.004, 0.028, 0.070, and 0.174 W m"−"2 ppb"−"1 and global warming potentials (100 year horizon) of 5, 8, 15, and 1775, respectively. Quantum chemistry calculations generally predict larger band intensities than the experimental values. The best agreement with experiments is obtained in MP2(Full) calculations employing basis sets of at least triple-zeta quality augmented by diffuse functions. The B3LYP functional is found ill-suited for calculating vibrational frequencies and infrared intensities of halocarbons. - Highlights: • Infrared spectra reported for CH_3Cl, CH_2Cl_2, CHCl_3, and CCl_4. • REs of CH_3Cl, CH_2Cl_2, CHCl_3, and CCl_4 are 0.004, 0.028, 0.070, and 0.174 W m"−"2 ppb"−"1, respectively. • GWPs of CH_3Cl, CH_2Cl_2, CHCl_3, and CCl_4 are 5, 8, 15, and 1775, respectively.

  2. Antioxidative and cytoprotective effects of andrographolide against CCl4-induced hepatotoxicity in HepG2 cells.

    Science.gov (United States)

    Krithika, R; Verma, R J; Shrivastav, P S

    2013-05-01

    This article describes antioxidative and cytoprotective property of andrographolide, a major active component of the plant Andrographis paniculata (A. paniculata). High yields (2.7%) of andrographolide was isolated from the aerial parts of this plant via silica column chromatography. The purity of the compound was determined by high-performance thin-layer chromatography (HPTLC) and reversed phase high-performance liquid chromatography (HPLC) analysis. The structure was elucidated using techniques such as UV-visible spectrophotometry, elemental analysis, Fourier transform infrared (FT-IR), (1)H nuclear magnetic resonance ((1)H NMR), (13)C nuclear magnetic resonance ((13)C NMR) and mass spectral analysis and the data obtained were comparable with reported results. It was observed that andrographolide exhibited significant antioxidative property (IC50 = 3.2 µg/ml) by its ability to scavenge a stable free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH) as compared to known antioxidants like ascorbic acid, butylated hydroxy toluene (BHT) and the plant extract. The cytoprotective role of andrographolide against carbon tetrachloride (CCl4) toxicity in human hepatoma HepG2 cell line was assessed using trypan blue exclusion test, 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, by estimation of various leakage enzymes and by measuring the glutathione levels. The recovery obtained for andrographolide treatment in the presence of CCl4 was two-fold compared to A. paniculata extract for all other related biochemical parameters investigated. The results of the study indicate that andrographolide is a potent inhibitor of CCl4-mediated lipid peroxidation.

  3. Assessment of the hepatoprotective activity of the seeds of Hunteria umbellata (Hallier F.) on carbon tetrachloride (CCl4) induced liver damage in Wistar albino rats

    Science.gov (United States)

    Ogunlana, Olubanke Olujoke; Ogunlana, Oluseyi Ebenezer; Adelani, Isaacson Bababode; Adebayo, Angie Osariem Igbinoba; David, Opetoritse Laju; Adeleye, Oluwaseye Joseph; Udeogu, Stephanie Adaora; Adeyemi, Alaba Oladipupo; Akinyele, Julie Oluranti

    2018-04-01

    This study was designed to evaluate the hepatoprotective activity of the seeds of Hunteria umbellata (HU) on carbon tetrachloride (CCl4) induced rats. Rats of groups 1 (normal control), 3 and 5 were not treated with CCl4 while rats of groups 2 (negative control), 4 and 6 rats were treated with single dose of CCl4 (2 ml/kg) by intraperitoneal administration. Normal control group 1 rats were given distilled water, groups 3 and 4 rats were given 50 mg/kg of silymarin while groups 5 and 6 rats were given 500 mg/kg of HU. Treatment was administered orally for 28 days and sacrificed on the 29th day after an overnight fast. The weights of the rats were taken before and after the treatment. Blood samples were collected in heparinized tubes and biochemical analysis of liver functions and lipid profile tests were carried out on plasma. There was a significant change (pgroup treated with HU compared to the CCl4 untreated group 2 animals. The results obtained showed that the ethanolic extract of HU has hepatoprotective property.

  4. Antioxidative effects of pumpkin seed (Cucurbita pepo) protein isolate in CCl4-induced liver injury in low-protein fed rats.

    Science.gov (United States)

    Nkosi, C Z; Opoku, A R; Terblanche, S E

    2006-11-01

    The effects of pumpkin seed (Cucurbita pepo) protein isolate on the plasma activity levels of catalase (CA), superoxide dismutase (SOD), glutathione peroxidase (GSHpx) and total antioxidant capacity (TAC) as well as glucose-6-phosphatase (G6Pase) in liver homogenates and lipid peroxidation (LPO-malondialdehyde-MDA) levels in liver homogenates and liver microsomal fractions against carbon tetrachloride (CCl(4))-induced acute liver injury in low-protein fed Sprague-Dawley rats (Rattus norvegicus) were investigated. A group of male Sprague-Dawley rats maintained on a low-protein diet for 5 days were divided into three subgroups. Two subgroups were injected with carbon tetrachloride and the other group with an equivalent amount of olive oil. Two hours after CCl(4) intoxication one of the two subgroups was administered with pumpkin seed protein isolate and thereafter switched onto a 20% pumpkin seed protein isolate diet. The other two groups of rats were maintained on the low-protein diet for the duration of the investigation. Groups of rats from the different subgroups were killed at 24, 48 and 72 h after their respective treatments. After 5 days on the low-protein diet the activity levels of all the enzymes as well as antioxidant levels were significantly lower than their counterparts on a normal balanced diet. However, a low-protein diet resulted in significantly increased levels of lipid peroxidation. The CCl(4) intoxicated rats responded in a similar way, regarding all the variables investigated, to their counterparts on a low-protein diet. The administration of pumpkin seed protein isolate after CCl(4) intoxication resulted in significantly increased levels of all the variables investigated, with the exception of the lipid peroxidation levels which were significantly decreased. From the results of the present study it is concluded that pumpkin seed protein isolate administration was effective in alleviating the detrimental effects associated with protein

  5. Kinetics of electron-induced decomposition of CF2Cl2 coadsorbed with water (ice): A comparison with CCl4

    International Nuclear Information System (INIS)

    Faradzhev, N.S.; Perry, C.C.; Kusmierek, D.O.; Fairbrother, D.H.; Madey, T.E.

    2004-01-01

    The kinetics of decomposition and subsequent chemistry of adsorbed CF 2 Cl 2 , activated by low-energy electron irradiation, have been examined and compared with CCl 4 . These molecules have been adsorbed alone and coadsorbed with water ice films of different thicknesses on metal surfaces (Ru; Au) at low temperatures (25 K; 100 K). The studies have been performed with temperature programmed desorption (TPD), reflection absorption infrared spectroscopy (RAIRS), and x-ray photoelectron spectroscopy (XPS). TPD data reveal the efficient decomposition of both halocarbon molecules under electron bombardment, which proceeds via dissociative electron attachment (DEA) of low-energy secondary electrons. The rates of CF 2 Cl 2 and CCl 4 dissociation increase in an H 2 O (D 2 O) environment (2-3x), but the increase is smaller than that reported in recent literature. The highest initial cross sections for halocarbon decomposition coadsorbed with H 2 O, using 180 eV incident electrons, are measured (using TPD) to be 1.0±0.2x10 -15 cm 2 for CF 2 Cl 2 and 2.5±0.2x10 -15 cm 2 for CCl 4 . RAIRS and XPS studies confirm the decomposition of halocarbon molecules codeposited with water molecules, and provide insights into the irradiation products. Electron-induced generation of Cl - and F - anions in the halocarbon/water films and production of H 3 O + , CO 2 , and intermediate compounds COF 2 (for CF 2 Cl 2 ) and COCl 2 , C 2 Cl 4 (for CCl 4 ) under electron irradiation have been detected using XPS, TPD, and RAIRS. The products and the decomposition kinetics are similar to those observed in our recent experiments involving x-ray photons as the source of ionizing irradiation

  6. CCL2 recruits T cells into the brain in a CCR2-independent manner

    DEFF Research Database (Denmark)

    Cédile, Oriane; Wlodarczyk, Agnieszka; Owens, Trevor

    2017-01-01

    CCR2, a receptor for CCL2. Expression of another receptor for CCL2, CCR4, and CXCR3, a receptor for CXCL10, which was also induced, were both increased in CCL2-treated CNS. CCR4 was expressed by neurons and astrocytes as well as CD4 T cells, and CXCR3 was expressed by CD4 and CD8 T cells. Chemokine...

  7. Vibrational Spectroscopy of the CCl[subscript 4] v[subscript 1] Mode: Theoretical Prediction of Isotopic Effects

    Science.gov (United States)

    Gaynor, James D.; Wetterer, Anna M.; Cochran, Rea M.; Valente, Edward J.; Mayer, Steven G.

    2015-01-01

    Raman spectroscopy is a powerful experimental technique, yet it is often missing from the undergraduate physical chemistry laboratory curriculum. Tetrachloromethane (CCl[subscript 4]) is the ideal molecule for an introductory vibrational spectroscopy experiment and the symmetric stretch vibration contains fine structure due to isotopic variations…

  8. Effect of selected natural products, thioproline and pegasys on hepatic platelet activating factor (PAF) in CCL4-induced hepatic fibrosis in rats

    International Nuclear Information System (INIS)

    Badria, Farid A.

    2007-01-01

    This study aimed to estimate hepatic levels of platelet activating factor (PAF) in liver fibrosis induced by CCl4 in rats. A group of selected natural products; boswellic acids, curcumin and glycrrhizin (preparation named OMNI; a drug under clinical trials for treatment of hepatitis C virus), Mirazid (a commercially available schistomicidal drug), Thioproline (a commercially available hepatoprotective agent) and Pegasys (peg interferon alpha-2a; a commercially available therapy for treatment of Hepatitis C virus) were examined for their effect on hepatic PAF groups each comprised 9 rats. Group 1 was treated only with CCl4, group 2 to 5 were treated with OMNI, Mirazid, Thioproline and Pegasys, respectively whereas the 6th group was the normal control group (with no treatment, except an injection of the vehicle). Liver damage was induced in all groups except normal control group (groups 1 to 5) by i.p. injection of 40% CCl4 in corn oil (0.375 ml/kg) 3 times a week for 3 weeks. One week after CCl4 intoxication, all tested drugs were injected i.p. daily for 3 weeks. Hepatic PAF concentration was estimated by HPTLC (high performance thin layer chromatography), while levels of serum transminases (ALT, AST), hepatic hydroxyproline (as marker of liver fibrosis), serum malondialdehyde and catalase (as markers of oxidative stress) were estimated sepctrophotometrically. The hepatic PAF levels were significantly higher in CCl4 group (24.24+-2.01 pmol equiv. /mg) (p<0.001). Treatment with OMNI, Mirazid, Thioproline and Pegasys reduced hepatic PAF significantly to be 11.84+-0.22, 14.5+-1.00, 13.17+-0, 54 and 14.26+-1.09pmol equiv. /mg respectively. This study may add further rational to the anti-fibrotic activity of the tested drugs via reduction of hepatic PAF. (author)

  9. Biochemical and molecular modulation of CCl4-induced peripheral and central damage by Tilia americana var. mexicanaextracts.

    Science.gov (United States)

    Coballase-Urrutia, Elvia; Cárdenas-Rodríguez, Noemí; González-García, María Carolina; Núñez-Ramírez, Eithan; Floriano-Sánchez, Esaú; González-Trujano, María Eva; Fernández-Rojas, Berenice; Pedraza-Chaverrí, José; Montesinos-Correa, Hortencia; Rivera-Espinosa, Liliana; Sampieri, Aristides Iii; Carmona-Aparicio, Liliana

    2017-03-01

    Around the world, species from the genus Tilia are commonly used because of their peripheral and central medicinal effects; they are prepared as teas and used as tranquilizing, anticonvulsant, and analgesic agents. In this study, we provide evidence of the protective effects of organic and aqueous extracts (100 mg/kg, i.p.) obtained from the leaves of Tilia americana var. mexicana on CCl 4 -induced liver and brain damage in the rat. Protection was observed in the liver and brain (cerebellum, cortex and cerebral hemispheres) by measuring the activity of antioxidant enzymes and levels of malondialdehyde (MDA) using spectrophotometric methods. Biochemical parameters were also assessed in serum samples from the CCl 4 -treated rats. The T. americana var. mexicana leaf extracts provided significant protection against CCl 4 -induced peripheral and central damage by increasing the activity of antioxidant enzymes, diminishing lipid peroxidation, and preventing alterations in biochemical serum parameters, such as the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), γ-globulin (γ-GLOB), serum albumin (ALB), total bilirubin (BB), creatinine (CREA) and creatine kinase (CK), relative to the control group. Additionally, we correlated gene expression with antioxidant activity in the experimental groups treated with the organic and aqueous Tilia extracts and observed a non-statistically significant positive correlation. Our results provide evidence of the underlying biomedical properties of T. americana var. mexicana that confer its neuro- and hepatoprotective effects.

  10. Molecular beam electric deflection of the tetrahalides CF4, CCl4, SiF4, SiCl4, GeCl4, TiF4, TiCl4, VF4, and VCl4

    International Nuclear Information System (INIS)

    Muenter, A.A.; Dyke, T.R.; Falconer, W.E.; Klemperer, W.

    1975-01-01

    Using molecular beam electric deflection, the temperature dependence of polar behavior has been studied for the molecules CF 4 , CCl 4 , SiF 4 , SiCl 4 , GeCl 4 , TiF 4 TiCl 4 , VF 4 , VF 4 , and VCl 4 . A number of these molecules show polar behavior consistent with a vibrationally induced dipole moment for states with one or both of the triply degenerate vibrations excited. In four of the tetrachloride species, the presence of a vibrationally induced dipole moment was confirmed by the change in polar behavior with isotopic substituion of the Cl atoms. The deflection behavior of the transition metal tetrahalides varied from nonpolar in VCl 4 to very polar in TiF 4

  11. Hepatoprotective effect of ethanol extract from Berchemia lineate against CCl4-induced acute hepatotoxicity in mice.

    Science.gov (United States)

    Li, Cong; Yi, Li-Tao; Geng, Di; Han, Yuan-Yuan; Weng, Lian-Jin

    2015-05-01

    The roots of Berchemia lineate (L.) DC. (Rhamnaceae) have been long used as a remedy for the treatment of some diseases in Guangxi Province, China. The present study investigates the hepatoprotective effect of Berchemia lineate ethanol extract (BELE) on CCl4-induced acute liver damage in mice. Effect of BELE administrated for 7 consecutive days was evaluated in mice by the serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total bilirubin (TBIL), albulin (ALB), globulin (GLB), and total protein (TP) levels, as well as liver superoxide dismutase (SOD) activity and malondialdehyde (MDA) level. Moreover, histopathological examinations were also taken. Compared with the model group, administration of 400 mg/kg BELE for 7 d in mice significantly decreased the serum ALT (56.25 U/L), AST (297.67 U/L), ALP (188.20 U/L), and TBIL (17.90 mol/L), along with the elevation of TP (64.67 g/L). In addition, BELE (100, 200, and 400 mg/kg, i.g.) treated mice recorded a dose-dependent increment of SOD (291.17, 310.32, and 325.67 U/mg prot) and reduction of MDA (7.27, 6.77, and 5.33 nmol/mg prot) levels. Histopathological examinations also confirmed that BELE can ameliorate CCl4-induced liver injuries, characterized by extensive hepatocellular degeneration/necrosis, inflammatory cell infiltration, congestion, and sinusoidal dilatation. The results indicated that BELE possessed remarkable protective effect against acute hepatotoxicity and oxidative injuries induced by CCl4, and that the hepatoprotective effects of BELE may be due to both the inhibition of lipid peroxidation and the increase of antioxidant activity.

  12. Cross section and asymmetry parameter calculations for the C 1s photoionization of CH4, CF4, and CCl4

    International Nuclear Information System (INIS)

    Natalense, Alexandra P. P.; Brescansin, Luiz M.; Lucchese, Robert R.

    2003-01-01

    We have computed cross sections and asymmetry parameters for the C 1s photoionization of CX 4 (X=H, F, Cl) using the Schwinger variational method with Pade corrections. We present a comparative study that shows the influence of the identity of the X atom on the computed cross sections. Predicted cross sections are in good agreement with available photoionization and photoabsorption experimental data. We conclude that the presence of heavy outer atoms produces resonance structures in the photoionization cross sections and in the asymmetry parameters. We find a single nonvalence resonant state in the photoionization of CF 4 and multiple resonances in CCl 4 that have significant d-orbital character in the vicinity of the Cl atoms

  13. Crystal structure, hydrogen bonding, and sup 8 sup 1 Br NQR of low-temperature phase of 4-aminopyridinium tetrabromoantimonate (3)

    CERN Document Server

    Hashimoto, M; Fuess, H; Svoboda, I; Ehrenberg, H

    2003-01-01

    The crystal structure of the low-temperature phase (LTP) of the title compound was determined at 220 K (monoclinic, P2 sub 1 sub / sub c). The 4-aminopyridinium cations (4-NH sub 2 C sub 5 H sub 4 NH sup +) were found to be ordered in LTP, while being severely disordered in the room-temperature phase (monoclinic, C2/c). The tetrabromoantimonate anions (SbBr sub 4 sup -) were incorporated into the infinite polyanion chains of irregular SbBr sub 6 octahedra with two-edges sharing. The trans-Br-Sb-Br moiety in the SbBr sub 4 sup - anion was approximately symmetric differing from the asymmetric Br-Sb centre dot centre dot centre dot Br moiety found in LTP of pyridinium tetrabromoantimonate (3). The N-H moieties in both of the pyridine ring and the amino (-NH sub 2) group participate in the formation of N-H centre dot centre dot centre dot Br hydrogen bonds. It was shown that the sup 8 sup 1 Br NQR spectrum of LTP is closely related to the anion structure and the hydrogen bonds. The distinctive anion structures, a...

  14. The fate of atmospheric phosgene and the stratospheric chlorine loadings of its parent compounds: CCl4, C2Cl4, C2HCL3, CH3CCl3, and CHCl3

    Science.gov (United States)

    Kindler, T. P.; Chameides, W. L.; Wine, P. H.; Cunnold, D. M.; Alyea, F. N.; Franklin, J. A.

    1995-01-01

    A study of the tropospheric and stratospheric cycles of phosgene is carried out to determine its fate and ultimate role in controlling the ozone depletion potentials of its parent compounds. Tropospheric phosgene is produced from the OH-initiated oxidation of C2Cl4, CH3CCl3, CHCl3, and C2HCl3. Simulations using a two-dimensional model indicate that these processes produce about 90 pptv/yr of tropospheric phosgene with an average concentration of about 18 pptv, in reasonable agreement with observations. We estimate a residence time of about 70 days for tropospheric phosgene, with the vast majority being removed by hydrolysis in cloudwater. Only about 0.4% of the phosgene produced in the troposphere avoids wet removal and is transported to the stratosphere, where its chlorine can be released to participate in the catalytic destruction of ozone. Stratospheric phosgene is produced from the photochemical degradation of CCl4, C2Cl4, CHCl3, and CH3CCl3 and is removed by photolysis and downward transport to the troposphere. Model calculations, in good agreement with observations, indicate that these processes produce a peak stratospheric concentration of about 25-30 pptv at an altitude of about 25 km. In contrast to tropospheric phosgene, stratospheric phosgene is found to have a lifetime against photochemical removal of the order of years. As a result, a significant portion of the phosgene that is produced in the stratosphere is ultimately returned to the troposphere, where it is rapidly removed by clouds. This phenomenon effectively decreases the amount of reactive chlorine injected into the stratosphere and available for ozone depletion from phosgene's parent compounds. A similar phenomenon due to the downward transport of stratospheric COFCl produced from CFC-11 is estimated to cause a 7% decrease in the amount of reactive chlorine injected into the stratosphere from this compound. Our results are potentially sensitive to a variety of parameters, most notably the rate

  15. CCL2 is critical for immunosuppression to promote cancer metastasis.

    Science.gov (United States)

    Kudo-Saito, Chie; Shirako, Hiromi; Ohike, Misa; Tsukamoto, Nobuo; Kawakami, Yutaka

    2013-04-01

    We previously found that cancer metastasis is accelerated by immunosuppression during Snail-induced epithelial-to-mesenchymal transition (EMT). However, the molecular mechanism still remained unclear. Here, we demonstrate that CCL2 is a critical determinant for both tumor metastasis and immunosuppression induced by Snail(+) tumor cells. CCL2 is significantly upregulated in various human tumor cells accompanied by Snail expression induced by snail transduction or TGFβ treatment. The Snail(+) tumor-derived CCL2 amplifies EMT events in other cells including Snail(-) tumor cells and epithelial cells within tumor microenvironment. CCL2 secondarily induces Lipocalin 2 (LCN2) in the Snail(+) tumor cells in an autocrine manner. CCL2 and LCN2 cooperatively generate immunoregulatory dendritic cells (DCreg) having suppressive activity accompanied by lowered expression of costimulatory molecules such as HLA-DR but increased expression of immunosuppressive molecules such as PD-L1 in human PBMCs. The CCL2/LCN2-induced DCreg cells subsequently induce immunosuppressive CD4(+)FOXP3(+) Treg cells, and finally impair tumor-specific CTL induction. In murine established tumor model, however, CCL2 blockade utilizing the specific siRNA or neutralizing mAb significantly inhibits Snail(+) tumor growth and metastasis following systemic induction of anti-tumor immune responses in host. These results suggest that CCL2 is more than a chemoattractant factor that is the significant effector molecule responsible for immune evasion of Snail(+) tumor cells. CCL2 would be an attractive target for treatment to eliminate cancer cells via amelioration of tumor metastasis and immunosuppression.

  16. Continuous high expression of XBP1 and GRP78 is important for the survival of bone marrow cells in CCl4-treated cirrhotic liver

    International Nuclear Information System (INIS)

    Marumoto, Yoshio; Terai, Shuji; Urata, Yohei; Matsumoto, Toshihiko; Mizunaga, Yuko; Yamamoto, Naoki; Jin, Haiyan; Fujisawa, Koichi; Murata, Tomoaki; Shinoda, Koh; Nishina, Hiroshi; Sakaida, Isao

    2008-01-01

    We have previously shown that infusion of bone marrow cells (BMC) improves CCl 4 -induced cirrhosis. However, it is unclear why the injected BMC are resistant to CCl 4 damage and subsequently improve the local microenvironment in damaged liver. To analyze the cellular phenomena involved in this process, we studied the damaged liver using electron microscopy. We found that CCl 4 caused rough endoplasmic reticula to swell in hepatocytes. To analyze the gene expression patterns associated with this process, we conducted PCR-selected suppressive subtractive hybridization. We found that expression levels of HSP84, HSP40, and XBP1 differed markedly between control liver and liver infused with BMC. Immunohistochemical staining revealed that expression levels of HSP84 and HSP40 were markedly higher in the early phase of differentiation immediately after BMC infusion, but decreased over time. XBP1 expression remained high during the late phase, and GRP78 expression increased with XBP1 activation. We also found that GFP-positive BMC expressed XBP1 and GRP78. XBP1 and GRP78 are associated with ER stress. Thus, continuous high XBP1 and GRP78 expression might be essential for the survival and proliferation of BMC in a CCl 4 -induced persistent liver damage environment

  17. Effects of curcumin on antioxidative activities and cytokine production in Jian carp (Cyprinus carpio var. Jian) with CCl4-induced liver damage.

    Science.gov (United States)

    Cao, Liping; Ding, Weidong; Du, Jingliang; Jia, Rui; Liu, Yingjuan; Zhao, Caiyuan; Shen, Yujin; Yin, Guojun

    2015-03-01

    We investigated the protective effects of curcumin on liver-damaged Cyprinus carpio var. Jian (Jian carp). The carp were fed 0.1%, 0.5%, or 1.0% curcumin for 60 days, then injected intraperitoneally with 30% carbon tetrachloride solution. Liver and blood samples were collected to measure the liver index, serum- and liver-associated enzymes, liver histology, nuclear factor-κB (NF-κB)/c-Rel, interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and IL-12 mRNA expression, and the level of NF-κB/c-Rel protein in the liver, and for a comet assay. We found that 0.5% and 1.0% curcumin significantly reduced the CCl(4)-induced increase in the liver index. The comet assay showed that the tail moment, olive tail moment, tail length, and tail DNA% improved in fish pretreated with 0.5 or 1.0% curcumin. CCl(4)-induced histological changes, including extensive hepatocyte degeneration, indistinct cell borders, nuclear condensation, and karyolysis were clearly reduced after treatment with 0.5% and 1.0% curcumin. Moreover, 0.5% and 1.0% curcumin significantly inhibited the CCl(4)-induced increase in serum glutamic oxaloacetic transaminase and promoted the restoration of superoxide dismutase in the liver; 1.0% curcumin significantly reduced serum glutamic pyruvic transaminase and lactate dehydrogenase and hepatic malondialdehyde, but significantly increased the total antioxidant capacity and glutathione levels in the liver. The CCl(4)-induced upregulation of NF-κB/c-Rel, IL-1β, and TNF-α mRNAs and NF-κB/c-Rel protein levels was inhibited by 0.5% and 1.0% curcumin, and IL-12 mRNA was reduced by all three doses of curcumin. The effects of curcumin on the liver index, enzymes, histological changes, and cytokines were dose-dependent. Our results indicate that curcumin reduces CCl(4)-induced liver damage in Jian carp by upregulating antioxidative activities and inhibiting NF-κB, IL-1β, TNF-α, and IL-12 expression. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Intrapulmonary Human Cytomegalovirus Replication in Lung Transplant Recipients Is Associated With a Rise of CCL-18 and CCL-20 Chemokine Levels.

    Science.gov (United States)

    Weseslindtner, Lukas; Görzer, Irene; Roedl, Kevin; Küng, Erik; Jaksch, Peter; Klepetko, Walter; Puchhammer-Stöckl, Elisabeth

    2017-01-01

    In lung transplant recipients (LTRs), human cytomegalovirus (HCMV) DNA detection in the bronchoalveolar lavage fluid (BALF) indicates HCMV replication in the pulmonary compartment. Such local HCMV replication episodes may remain asymptomatic or may lead to symptomatic HCMV disease. Here, we investigated LTRs with intrapulmonary HCMV replication for the chemokines CCL-18 and CCL-20. In particular, we analyzed whether these chemokines rise in the allograft and/or the blood and are associated with HCMV disease. CCL-18 and CCL-20 levels were quantitated by ELISA in BALF and serum samples from 60 LTRs. During the posttransplant follow-up, these LTRs displayed HCMV DNA detection in the BALF by PCR, whereas other infectious agents were undetectable. Furthermore, we investigated samples from 10 controls who did not display any HCMV replication episode during the follow-up. HCMV replication in the allograft was associated with a significant increase of CCL-18 and CCL-20 BALF levels (P Wilcoxon signed-rank test) and a significant rise of CCL-20 (P Wilcoxon signed-rank test) but not of CCL-18 in the blood. In controls, no such chemokine increase was observed. Furthermore, CCL-18 BALF levels were significantly higher in 8 LTRs who additionally developed HCMV disease, as compared with the other 52 patients in whom HCMV replication remained asymptomatic (P test). HCMV replication in the allograft causes an intrapulmonary increase of CCL-18 and CCL-20 and a systemic rise of CCL-20 serum levels. Strong intrapulmonary CCL-18 responses are associated with symptomatic HCMV disease, proposing that CCL-18 BALF levels could serve as a marker.

  19. Preventive activity of banana peel polyphenols on CCl4-induced experimental hepatic injury in Kunming mice.

    Science.gov (United States)

    Wang, Rui; Feng, Xia; Zhu, Kai; Zhao, Xin; Suo, Huayi

    2016-05-01

    The aim of the present study was to evaluate the preventive effects of banana peel polyphenols (BPPs) against hepatic injury. Mice were divide into normal, control, 100 mg/kg and 200 mg/kg banana peel polyphenol and silymarin groups. All the mice except normal mice were induced with hepatic damage using CCl 4 . The serum and tissue levels of mice were determined by a kit and the tissues were further examined by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot analysis. BPPs reduced the serum levels of aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase in a CCl 4 -induced mouse model of hepatic injury. Furthermore, BPPs reduced the levels of malondialdehyde and triglyceride, while increasing glutathione levels in the serum and liver tissues of mice. In addition, the effects of 200 mg/kg treatment were more evident, and these effects were comparable to those of the drug silymarin. Serum levels of the cytokines, interleukin (IL)-6, IL-12, tumor necrosis factor (TNF)-α and interferon-γ, were reduced in the mice treated with BPPs compared with injury control group mice, and these levels were comparable to those of the normal and silymarin-treated groups. Histopathological examination indicated that BPPs were able to reduce the extent of CCl 4 -induced liver tissue injury and protect the liver cells. Furthermore, the mRNA and protein expression levels of the inflammation-associated factors cyclooxygenase-2, nitric oxide synthase, TNF-α and IL-1β were reduced in mice treated with BPPs compared with the control group mice. Mice that received 200 mg/kg BPP exhibited reduced expression levels of these factors compared with mice that received 100 mg/kg BPP. In conclusion, the results of the present study suggested that BPPs exert a good preventive effect against hepatic injury.

  20. s-wave threshold in electron attachment - Observations and cross sections in CCl4 and SF6 at ultralow electron energies

    Science.gov (United States)

    Chutjian, A.; Alajajian, S. H.

    1985-01-01

    The threshold photoionization method was used to study low-energy electron attachment phenomena in and cross sections of CCl4 and SF6 compounds, which have applications in the design of gaseous dielectrics and diffuse discharge opening switches. Measurements were made at electron energies from below threshold to 140 meV at resolutions of 6 and 8 meV. A narrow resolution-limited structure was observed in electron attachment to CCl4 and SF6 at electron energies below 10 meV, which is attributed to the divergence of the attachment cross section in the limit epsilon, l approaches zero. The results are compared with experimental collisional-ionization results, electron-swarm unfolded cross sections, and earlier threshold photoionization data.

  1. Hepatoprotective properties of aqueous leaf extract of Persea Americana, Mill (Lauraceae) 'avocado' against CCL4-induced damage in rats.

    Science.gov (United States)

    Brai, Bartholomew I C; Adisa, Rahmat A; Odetola, Adebimpe A

    2014-01-01

    Natural products from plants have received considerable attention in recent years due to their diverse pharmacological properties, including antioxidants and hepatoprotective activities. The protective effects of aqueous extract of Persea americana (AEPA) against carbon tetrachloride (CCl4)-induced hepatotoxicity in male albino rats was investigated. Liver damage was induced in rats by administering a 1:1 (v/v) mixture of CCl4 and olive oil [3 ml/kg, subcutaneously (sc)] after pre-treatment for 7 days with AEPA. Hepatoprotective effects of AEPA was evaluated by estimating the activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and levels of total bilirubin (TBL). The effects of AEPA on biomarkers of oxidative damage (lipid peroxidation) and antioxidant enzymes namely, catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione S-transferase (GST) were measured in liver post mitochondrial fraction. AEPA and Reducdyn® showed significant (p<0.05) hepatoprotective activity by decreasing the activities of ALT, AST, ALP and reducing the levels of TBL. The activities of antioxidant enzymes, levels of malondialdehyde and protein carbonyls were also decreased dose-dependently in the AEPA-treated rats. Pre-treatment with AEPA also decreased the serum levels of glutathione significantly. These data revealed that AEPA possesses significant hepatoprotective effects against CCl4-induced toxicity attributable to its constituent phytochemicals. The mechanism of hepatoprotection seems to be through modulation of antioxidant enzyme system.

  2. The β-chemokines CCL2 and CCL7 are two novel differentiation factors for midbrain dopaminergic precursors and neurons

    International Nuclear Information System (INIS)

    Edman, Linda C.; Mira, Helena; Arenas, Ernest

    2008-01-01

    β-chemokines are secreted factors that regulate diverse functions in the adult brain, such as neuro-immune responses and neurotransmission, but their function in the developing brain is largely unknown. We recently found that the orphan nuclear receptor, Nurr1, up regulates CCL2 and CCL7 in neural stem cells, suggesting a possible function of β-chemokines in midbrain development. Here we report that two β-chemokines, CCL2 and CCL7, and two of their receptors, CCR1 and CCR2, are expressed and developmentally regulated in the ventral midbrain (VM). Moreover, we found that the expression of CCL7 was down regulated in the Nurr1 knockout mice, linking CCL7 to dopamine (DA) neuron development. When the function of CCL2 and CCL7 was examined, we found that they selectively enhanced the differentiation of Nurr1+ precursors into DA neurons, but not their survival or progenitor proliferation in primary precursor cultures. Moreover, both CCL2 and CCL7 promoted neuritogenesis in midbrain DA neuron cultures. Thus, our results show for the first time a function of β-chemokines in the developing brain and identify β-chemokines as novel class of pro-differentiation factors for midbrain DA neurons. These data also suggest that β-chemokines may become useful tools to enhance the differentiation of DA cell preparations for cell replacement therapy and drug discovery in Parkinson's disease (PD)

  3. Exhaust properties of centre-column-limited plasmas on MAST

    International Nuclear Information System (INIS)

    Maddison, G.P.; Akers, R.J.; Brickley, C.; Gryaznevich, M.P.; Lott, F.C.; Patel, A.; Sykes, A.; Turner, A.; Valovic, M.

    2007-01-01

    The lowest aspect ratio possible in a spherical tokamak is defined by limiting the plasma on its centre column, which might therefore maximize many physics benefits of this fusion approach. A key issue for such discharges is whether loads exhausted onto the small surface area of the column remain acceptable. A first series of centre-column-limited pulses has been examined on MAST using fast infra-red thermography to infer incident power densities as neutral-beam heating was scanned from 0 to 2.5 MW. Simple mapping shows that efflux distributions on the column armour are governed mostly by magnetic geometry, which moreover spreads them advantageously over almost the whole vertical length. Hence steady peak power densities between sawteeth remained low, -2 , comparable with the target strike-point value in a reference diverted plasma at lower power. Plasma purity and normalized thermal energy confinement through the centre-column-limited (CCL) series were also similar to properties of MAST diverted cases. A major bonus of CCL geometry is a propensity for exhaust to penetrate through its inner scrape-off layer connecting to the column into an expanding outer plume, which forms a 'natural divertor'. Effectiveness of this process may even increase with plasma heating, owing to rising Shafranov shift and/or toroidal rotation. A larger CCL device could potentially offer a simpler, more economic next-step design

  4. Steatosis induced CCL5 contributes to early-stage liver fibrosis in nonalcoholic fatty liver disease progress.

    Science.gov (United States)

    Li, Bing-Hang; He, Fang-Ping; Yang, Xin; Chen, Yuan-Wen; Fan, Jian-Gao

    2017-02-01

    The rapidly increasing prevalence of nonalcoholic fatty liver disease (NAFLD) has become one of the major public health threats in China and worldwide. However, during the development of NAFLD, the key mechanism underlying the progression of related fibrosis remains unclear, which greatly impedes the development of optimal NAFLD therapy. In the current study, we were endeavored to characterize a proinflammatory cytokine, CCL5, as a major contributor for fibrosis in NAFLD. The results showed that CCL5 was highly expressed in fatty liver and NASH patients. In NAFLD rats induced by 8-week-HFD, CCL5 and its receptor, CCR5, were significantly up-regulated and liver fibrosis exclusively occurred in this group. In addition, we showed that hepatocytes are the major source contributing to this CCL5 elevation. Interestingly, a CCL5 inhibitor Met-CCL5, significantly decreased liver fibrosis but not hepatic steatosis. Using a cell model of hepatic steatosis, we found that the conditioned medium of lipid-overloaded hepatocytes (Fa2N-4 cells) which produced excessive CCL5 stimulated the profibrotic activities of hepatic stellate cells (LX-2) as manifested by increased migration rate, proliferation and collagen production of LX-2 cells. CCL5 knockdown in Fa2N-4 cells, Met-CCL5 or CCR5 antibody treatment on LX-2 cells all significantly inhibited the conditioned medium of FFA-treated Fa2N-4 cells to exert stimulatory effects on LX-2 cells. Consistently, the conditioned medium of Fa2N-4 cells with CCL5 over-expression significantly enhanced migration rate, cell proliferation and collagen production of LX-2 cells. All these results support that CCL5 produced by steatotic hepatocytes plays an essential role in fibrotic signaling machinery of NAFLD. In addition, we were able to identify C/EBP-β as the up-stream regulator of CCL5 gene transcription in hepatocytes treated with free fatty acid (FFA). Our data strongly supported that CCL5 plays a pivotal regulatory role in

  5. Dicranostiga leptopodu (Maxim.) Fedde extracts attenuated CCl4-induced acute liver damage in mice through increasing anti-oxidative enzyme activity to improve mitochondrial function.

    Science.gov (United States)

    Tang, Deping; Wang, Fang; Tang, Jinzhou; Mao, Aihong; Liao, Shiqi; Wang, Qin

    2017-01-01

    Dicranostiga Leptodu (Maxim.) fedde (DLF), a poppy plant, has been reported have many benefits and medicinal properties, including free radicals scavenging and detoxifying. However, the protective effect of DLF extracts against carbon tetrachloride (CCl 4 )-induced damage in mice liver has not been elucidated. Here, we demonstrated that DLF extracts attenuated CCl 4 -induced liver damage in mice through increasing anti-oxidative enzyme activity to improve mitochondrial function. In this study, the mice liver damage evoked by CCl 4 was marked by morphology changes, significant rise in lipid peroxidation, as well as alterations of mitochondrial respiratory function. Interestingly, pretreatment with DLF extracts attenuated CCl 4 -induced morphological damage and increasing of lipid peroxidation in mice liver. Additionally, DLF extracts improved mitochondrial function by preventing the disruption of respiratory chain and suppression of mitochondrial Na + K + -ATPase and Ca 2+ -ATPase activity. Furthermore, administration with DLF extracts elevated superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) levels and maintained the balance of redox status. This results showed that toxic protection effect of DLF extracts on mice liver is mediated by improving mitochondrial respiratory function and keeping the balance of redox status, which suggesting that DLF extracts could be used as potential toxic protection agent for the liver against hepatotoxic agent. Copyright © 2016. Published by Elsevier Masson SAS.

  6. Immunohistochemical Analysis of Platelet Extract Effects on Liver Injury Induced by CCl4 in Male Rats

    Directory of Open Access Journals (Sweden)

    Zahra Hesami

    2016-01-01

    Full Text Available Backgrounds & objectives: Liver damage results in a large accumulation of external cellular matrix that affects the function of this important body organ in a long term and finally stops its function completely. The growth factors existing in platelet extract are more cost-effective, available, and stable than recombinant ones. To determine whether the platelet extract effects on histological changes in liver injury induced by carbon tetrachloride (CCl4, we used immunohistochemical analysis in male rats. Methods: In this project the 28 male Wistar rats (250-300 g were randomly divided into 4 groups, each consisting of 7 animals. The rats were divided into four experimental groups as follows: the first group (sham intraperitoneally received only olive oil as the solvent of carbon tetrachloride; second group (CCl4 intraperitoneally received carbon tetrachloride dissolved in olive oil (ratio of about 1: 1 at a concentration of 1 ml/kg and a twice a week for eight weeks; third group subcutaneously received only platelet extract at a concentration of 0.5 ml/kg twice a week for three weeks; and fourth group received both CCl4 intraperitoneally for eight weeks and platelet extract subcutaneously for last three weeks. After 8 weeks of trial blood and liver sampling were done. Blood samples sent for enzymatic (AST, ALT tests and liver samples tested for histological and immunohistochemical studies. The data were analyzed using  one-way ANOVA followed by Tukey test by Graph pad Prism 5 software and data were considered significant at p≤ 0.05. Results: The results show that platelet extract causes a significant (p≤ 0.001 decrease in liver enzymes and albumin improves the function of liver. The level of alfa smooth muscle actin (α-SMA as an index of hepatic stellate cell activation was decreased by platelet extract administration which eventually reduced the necrosis and fibrosis induced by carbon tetrachloride in studied rats

  7. Differential elastic electron scattering cross sections for CCl4 by 1.5-100 eV energy electron impact

    Science.gov (United States)

    Limão-Vieira, P.; Horie, M.; Kato, H.; Hoshino, M.; Blanco, F.; García, G.; Buckman, S. J.; Tanaka, H.

    2011-12-01

    We report absolute elastic differential, integral and momentum transfer cross sections for electron interactions with CCl4. The incident electron energy range is 1.5-100 eV, and the scattered electron angular range for the differential measurements varies from 15°-130°. The absolute scale of the differential cross section was set using the relative flow technique with helium as the reference species. Comparison with previous total cross sections shows good agreement. Atomic-like behaviour in this scattering system is shown here for the first time, and is further investigated by comparing the CCl4 elastic cross sections to recent results on the halomethanes and atomic chlorine at higher impact energies [H. Kato, T. Asahina, H. Masui, M. Hoshino, H. Tanaka, H. Cho, O. Ingólfsson, F. Blanco, G. Garcia, S. J. Buckman, and M. J. Brunger, J. Chem. Phys. 132, 074309 (2010)], 10.1063/1.3319761.

  8. Inflammatory mediators in breast cancer: Coordinated expression of TNFα & IL-1β with CCL2 & CCL5 and effects on epithelial-to-mesenchymal transition

    International Nuclear Information System (INIS)

    Soria, Gali; Gutman, Mordechai; Ben-Baruch, Adit; Ofri-Shahak, Maya; Haas, Ilana; Yaal-Hahoshen, Neora; Leider-Trejo, Leonor; Leibovich-Rivkin, Tal; Weitzenfeld, Polina; Meshel, Tsipi; Shabtai, Esther

    2011-01-01

    The inflammatory chemokines CCL2 (MCP-1) & CCL5 (RANTES) and the inflammatory cytokines TNFα & IL-1β were shown to contribute to breast cancer development and metastasis. In this study, we wished to determine whether there are associations between these factors along stages of breast cancer progression, and to identify the possible implications of these factors to disease course. The expression of CCL2, CCL5, TNFα and IL-1β was determined by immunohistochemistry in patients diagnosed with: (1) Benign breast disorders (=healthy individuals); (2) Ductal Carcinoma In Situ (DCIS); (3) Invasive Ducal Carcinoma without relapse (IDC-no-relapse); (4) IDC-with-relapse. Based on the results obtained, breast tumor cells were stimulated by the inflammatory cytokines, and epithelial-to-mesenchymal transition (EMT) was determined by flow cytometry, confocal analyses and adhesion, migration and invasion experiments. CCL2, CCL5, TNFα and IL-1β were expressed at very low incidence in normal breast epithelial cells, but their incidence was significantly elevated in tumor cells of the three groups of cancer patients. Significant associations were found between CCL2 & CCL5 and TNFα & IL-1β in the tumor cells in DCIS and IDC-no-relapse patients. In the IDC-with-relapse group, the expression of CCL2 & CCL5 was accompanied by further elevated incidence of TNFα & IL-1β expression. These results suggest progression-related roles for TNFα and IL-1β in breast cancer, as indeed indicated by the following: (1) Tumors of the IDC-with-relapse group had significantly higher persistence of TNFα and IL-1β compared to tumors of DCIS or IDC-no-relapse; (2) Continuous stimulation of the tumor cells by TNFα (and to some extent IL-1β) has led to EMT in the tumor cells; (3) Combined analyses with relevant clinical parameters suggested that IL-1β acts jointly with other pro-malignancy factors to promote disease relapse. Our findings suggest that the coordinated expression of CCL2 & CCL5

  9. Quadra-quantum Dots and Related Patterns of Quantum Dot Molecules:

    Directory of Open Access Journals (Sweden)

    Somsak Panyakeow

    2010-10-01

    Full Text Available Abstract Laterally close-packed quantum dots (QDs called quantum dot molecules (QDMs are grown by modified molecular beam epitaxy (MBE. Quantum dots could be aligned and cross hatched. Quantum rings (QRs created from quantum dot transformation during thin or partial capping are used as templates for the formations of bi-quantum dot molecules (Bi-QDMs and quantum dot rings (QDRs. Preferable quantum dot nanostructure for quantum computation based on quantum dot cellular automata (QCA is laterally close-packed quantum dot molecules having four quantum dots at the corners of square configuration. These four quantum dot sets are called quadra-quantum dots (QQDs. Aligned quadra-quantum dots with two electron confinements work like a wire for digital information transmission by Coulomb repulsion force, which is fast and consumes little power. Combination of quadra-quantum dots in line and their cross-over works as logic gates and memory bits. Molecular Beam Epitaxial growth technique called ‘‘Droplet Epitaxy” has been developed for several quantum nanostructures such as quantum rings and quantum dot rings. Quantum rings are prepared by using 20 ML In-Ga (15:85 droplets deposited on a GaAs substrate at 390°C with a droplet growth rate of 1ML/s. Arsenic flux (7–8×10-6Torr is then exposed for InGaAs crystallization at 200°C for 5 min. During droplet epitaxy at a high droplet thickness and high temperature, out-diffusion from the centre of droplets occurs under anisotropic strain. This leads to quantum ring structures having non-uniform ring stripes and deep square-shaped nanoholes. Using these peculiar quantum rings as templates, four quantum dots situated at the corners of a square shape are regrown. Two of these four quantum dots are aligned either or , which are preferable crystallographic directions of quantum dot alignment in general.

  10. Chemokines CXCL10 and CCL2

    DEFF Research Database (Denmark)

    Sørensen, Torben Lykke; Sellebjerg, F; Jensen, C V

    2001-01-01

    leukocyte count, the CSF concentration of neopterin, matrix metalloproteinase (MMP)-9, and intrathecal IgG and IgM synthesis. The concentration of CCL2 increased between baseline for 3 weeks in both groups, more distinctly so in patients treated with methylprednisolone. CCL2 correlated negatively with MMP-9...... patients in relapse, whilst levels of CCL2 (MCP-1) were reduced. Here, we report a serial analysis of CSF CXCL10 and CCL2 concentrations in 22 patients with attacks of MS or acute optic neuritis (ON) treated with methylprednisolone, and 26 patients treated with placebo in two randomized controlled trials....... Chemokine concentrations were measured by enzyme linked immunosorbent assay (ELISA) in CSF obtained at baseline and after 3 weeks, and were compared with other measures of intrathecal inflammation. At baseline CSF concentrations of CCL2 were significantly lower in the patient group than in controls...

  11. Red Sea Suberea mollis Sponge Extract Protects against CCl4-Induced Acute Liver Injury in Rats via an Antioxidant Mechanism

    Directory of Open Access Journals (Sweden)

    Aymn T. Abbas

    2014-01-01

    Full Text Available Recent studies have demonstrated that marine sponges and their active constituents exhibited several potential medical applications. This study aimed to evaluate the possible hepatoprotective role as well as the antioxidant effect of the Red Sea Suberea mollis sponge extract (SMSE on carbon tetrachloride- (CCl4- induced acute liver injury in rats. In vitro antioxidant activity of SMSE was evaluated by 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH assay. Rats were orally administered three different concentrations (100, 200, and 400 mg/kg of SMSE and silymarin (100 mg/kg along with CCl4 (1 mL/kg, i.p., every 72 hr for 14 days. Plasma aspartate aminotransferase (AST, alanine aminotransferase (ALT, alkaline phosphatase (ALP, and total bilirubin were measured. Hepatic malondialdehyde (MDA, reduced glutathione (GSH, nitric oxide (NO, superoxide dismutase (SOD, glutathione peroxidase (GPx, and catalase (CAT were also measured. Liver specimens were histopathologically examined. SMSE showed strong scavenging activity against free radicals in DPPH assay. SMSE significantly reduced liver enzyme activities. Moreover, SMSE significantly reduced hepatic MDA formation. In addition, SMSE restored GSH, NO, SOD, GPx, and CAT. The histopathological results confirmed these findings. The results of this study suggested a potent protective effect of the SMSE against CCl4-induced hepatic injury. This may be due to its antioxidant and radical scavenging activity.

  12. Impact of a CXCL12/CXCR4 Antagonist in Bleomycin (BLM Induced Pulmonary Fibrosis and Carbon Tetrachloride (CCl4 Induced Hepatic Fibrosis in Mice.

    Directory of Open Access Journals (Sweden)

    Leola N Chow

    Full Text Available Modulation of chemokine CXCL12 and its receptor CXCR4 has been implicated in attenuation of bleomycin (BLM-induced pulmonary fibrosis and carbon tetrachloride (CCl4-induced hepatic injury. In pulmonary fibrosis, published reports suggest that collagen production in the injured lung is derived from fibrocytes recruited from the circulation in response to release of pulmonary CXCL12. Conversely, in hepatic fibrosis, resident hepatic stellate cells (HSC, the key cell type in progression of fibrosis, upregulate CXCR4 expression in response to activation. Further, CXCL12 induces HSC proliferation and subsequent production of collagen I. In the current study, we evaluated AMD070, an orally bioavailable inhibitor of CXCL12/CXCR4 in alleviating BLM-induced pulmonary and CCl4-induced hepatic fibrosis in mice. Similar to other CXCR4 antagonists, treatment with AMD070 significantly increased leukocyte mobilization. However, in these two models of fibrosis, AMD070 had a negligible impact on extracellular matrix deposition. Interestingly, our results indicated that CXCL12/CXCR4 signaling has a role in improving mortality associated with BLM induced pulmonary injury, likely through dampening an early inflammatory response and/or vascular leakage. Together, these findings indicate that the CXCL12-CXCR4 signaling axis is not an effective target for reducing fibrosis.

  13. Ethanol extract and its dichloromethane fraction of Alpinia oxyphylla Miquel exhibited hepatoprotective effects against CCl4-induced oxidative damage in vitro and in vivo with the involvement of Nrf2.

    Science.gov (United States)

    Zhang, Qiao; Hu, Xiaolong; Hui, Fuhai; Song, Qi; Cui, Can; Wang, Changli; Zhao, Qingchun

    2017-07-01

    Alpinia oxyphylla Miq. (A. oxyphylla), as a kind of medicine which also be used as food, is widely used in East Asian for the treatment of dyspepsia, diarrhea, abdominal pain and deficiency cold of spleen and stomach. This study aimed to investigate the protective effects of ethanol extract (EE) and its dichloromethane fraction (DM) of A. oxyphylla, which are rich in phenolic compounds, against CCl 4 -induced hepatic injury in vitro and in vivo. EE, DM and silymarin ameliorated CCl 4 -induced decrease of cell viability and increase of reactive oxygen species (ROS) in HepG2 cells. The CCl 4 -induced changes of glutathione (GSH) and methane dicarboxylic aldehyde (MDA) levels, and the decrease of superoxide dismutase (SOD) and catalase (CAT) activities were all restored with the pretreatment of EE, DM and silymarin. The results in liver injury model in rats showed that EE, DM and silymarin could significant decrease the levels of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and total bilirubin than the model group. Liver histopathology revealed that EE and DM attenuated the incidence of liver lesions triggered by CCl 4 intoxication. They also effectively relieved CCl 4 -induced oxidative damage. Western blot analysis indicated NF-E2-related factor (Nrf2) pathway played an critical role in the protection of EE and DM against CCl 4 -induced oxidative stress. In conclusion, the extracts from A. oxyphylla might be used as hepatoprotective agents. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  14. Quadra-Quantum Dots and Related Patterns of Quantum Dot Molecules: Basic Nanostructures for Quantum Dot Cellular Automata Application

    Directory of Open Access Journals (Sweden)

    Somsak Panyakeow

    2010-10-01

    Full Text Available Laterally close-packed quantum dots (QDs called quantum dot molecules (QDMs are grown by modified molecular beam epitaxy (MBE. Quantum dots could be aligned and cross hatched. Quantum rings (QRs created from quantum dot transformation during thin or partial capping are used as templates for the formations of bi-quantum dot molecules (Bi-QDMs and quantum dot rings (QDRs. Preferable quantum dot nanostructure for quantum computation based on quantum dot cellular automata (QCA is laterally close-packed quantum dot molecules having four quantum dots at the corners of square configuration. These four quantum dot sets are called quadra-quantum dots (QQDs. Aligned quadra-quantum dots with two electron confinements work like a wire for digital information transmission by Coulomb repulsion force, which is fast and consumes little power. Combination of quadra-quantum dots in line and their cross-over works as logic gates and memory bits. Molecular Beam Epitaxial growth technique called 'Droplet Epitaxy' has been developed for several quantum nanostructures such as quantum rings and quantum dot rings. Quantum rings are prepared by using 20 ML In-Ga (15:85 droplets deposited on a GaAs substrate at 390'C with a droplet growth rate of 1ML/s. Arsenic flux (7'8'10-6Torr is then exposed for InGaAs crystallization at 200'C for 5 min. During droplet epitaxy at a high droplet thickness and high temperature, out-diffusion from the centre of droplets occurs under anisotropic strain. This leads to quantum ring structures having non-uniform ring stripes and deep square-shaped nanoholes. Using these peculiar quantum rings as templates, four quantum dots situated at the corners of a square shape are regrown. Two of these four quantum dots are aligned either or, which are preferable crystallographic directions of quantum dot alignment in general.

  15. Inversion of spin levels in Ni sup 2 sup + : Zn(BF sub 4) sub 2 centre dot 6H sub 2 O at all -round compression and effect of transition coincidence

    CERN Document Server

    Krygin, I M; Nejlo, G N; Prokhorov, A D

    2001-01-01

    The study of the EPR spectrum of the Ni sup 2 sup + ion, replacing Zn sup 2 sup + in the Zn(BF sub 4) centre dot 6H sub 2 O crystals in the wide temperature range by the all-round compression in the X- and Q-ranges is carried out. The basic changes by varying temperature and pressure occur with the D parameter, characterizing the initial splitting by practically unchanged g-factor. The increase in the temperature is accompanied by the D nonlinear growth. The all-round compression linearly changes the initial splitting and leads to the change in the D-sign, signifying the spin levels inversion by 3.5 kbar. Coincidence of EPR lines, relative to different transitions, leads to the crevasse appearance in the outline of this one, that is connected with cross-relaxation inside the spin system

  16. Otitis Media and Nasopharyngeal Colonization in ccl3-/- Mice.

    Science.gov (United States)

    Deniffel, Dominik; Nuyen, Brian; Pak, Kwang; Suzukawa, Keigo; Hung, Jun; Kurabi, Arwa; Wasserman, Stephen I; Ryan, Allen F

    2017-11-01

    We previously found CC chemokine ligand 3 (CCL3) to be a potent effector of inflammation during otitis media (OM): exogenous CCL3 rescues the OM phenotype of tumor necrosis factor-deficient mice and the function of macrophages deficient in several innate immune molecules. To further delineate the role of CCL3 in OM, we evaluated middle ear (ME) responses of ccl3 -/- mice to nontypeable Haemophilus influenzae (NTHi). CCL chemokine gene expression was evaluated in wild-type (WT) mice during the complete course of acute OM. OM was induced in ccl3 -/- and WT mice, and infection and inflammation were monitored for 21 days. Phagocytosis and killing of NTHi by macrophages were evaluated by an in vitro assay. The nasopharyngeal bacterial load was assessed in naive animals of both strains. Many CCL genes showed increased expression levels during acute OM, with CCL3 being the most upregulated, at levels 600-fold higher than the baseline. ccl3 -/- deletion compromised ME bacterial clearance and prolonged mucosal hyperplasia. ME recruitment of leukocytes was delayed but persisted far longer than in WT mice. These events were linked to a decrease in the macrophage capacity for NTHi phagocytosis and increased nasopharyngeal bacterial loads in ccl3 -/- mice. The generalized impairment in inflammatory cell recruitment was associated with compensatory changes in the expression profiles of CCL2, CCL7, and CCL12. CCL3 plays a significant role in the clearance of infection and resolution of inflammation and contributes to mucosal host defense of the nasopharyngeal niche, a reservoir for ME and upper respiratory infections. Therapies based on CCL3 could prove useful in treating or preventing persistent disease. Copyright © 2017 American Society for Microbiology.

  17. HMG-CoA reductase regulates CCL17-induced colon cancer cell migration via geranylgeranylation and RhoA activation

    International Nuclear Information System (INIS)

    Al-Haidari, Amr A.; Syk, Ingvar; Thorlacius, Henrik

    2014-01-01

    Highlights: • Simvastatin blocked CCL17-induced and CCR4-dependent RhoA activation in HT29 cells. • CCL17/CCR4-mediated migration of colon cancer cells was antagonised by simvastatin. • Cell migration recovered by adding Mevalonate and geranylgeranyl pyrophosphate. • Targeting HMG-CoA reductase might be useful to inhibit colon cancer metastasis. - Abstract: Background: Simvastatin is widely used to lower cholesterol levels in patients with cardiovascular diseases, although accumulating evidence suggests that statins, such as simvastatin, also exert numerous anti-tumoral effects. Aim: The aim of this study was to examine the effect of simvastatin on colon cancer cell migration. Methods: Migration assays were performed to evaluate CCL17-induced colon cancer cell (HT-29) chemotaxis. In vitro tumor growth and apoptosis were assessed using a proliferation assay and annexin V assay, respectively. Active RhoA protein levels in CCL17-stimulated colon cancer cells were quantified using a G-LISA assay. Results: We found that simvastatin dose-dependently decreased CCL17-induced colon cancer cell migration. Simvastatin had no effect on colon cancer cell proliferation or apoptosis. Inhibition of beta chemokine receptor 4, CCR4, reduced CCL17-evoked activation of RhoA in colon cancer cells. Moreover, administration of mevalonate reversed the inhibitory effect of simvastatin on CCL17-induced colon cancer cell migration. Interestingly, co-incubation with geranylgeranyl pyrophosphate (GGPP) antagonized the inhibitory impact of simvastatin on colon cancer cell migration triggered by CCL17. Moreover, we observed that simvastatin decreased CCL17-induced activation of RhoA in colon cancer cells. Administration of mevalonate and GGPP reversed the inhibitory effect of simvastatin on CCL17-provoked RhoA activation in colon cancer cells. Conclusions: Taken together, our findings show for the first time that HMG-CoA reductase regulates CCL17-induced colon cancer cell migration via

  18. Non-invasive evaluation of liver stiffness after splenectomy in rabbits with CCl4-induced liver fibrosis.

    Science.gov (United States)

    Wang, Ming-Jun; Ling, Wen-Wu; Wang, Hong; Meng, Ling-Wei; Cai, He; Peng, Bing

    2016-12-14

    To investigate the diagnostic performance of liver stiffness measurement (LSM) by elastography point quantification (ElastPQ) in animal models and determine the longitudinal changes in liver stiffness by ElastPQ after splenectomy at different stages of fibrosis. Liver stiffness was measured in sixty-eight rabbits with CCl 4 -induced liver fibrosis at different stages and eight healthy control rabbits by ElastPQ. Liver biopsies and blood samples were obtained at scheduled time points to assess liver function and degree of fibrosis. Thirty-one rabbits with complete data that underwent splenectomy at different stages of liver fibrosis were then included for dynamic monitoring of changes in liver stiffness by ElastPQ and liver function according to blood tests. LSM by ElastPQ was significantly correlated with histologic fibrosis stage ( r = 0.85, P fibrosis, moderate fibrosis, and cirrhosis, respectively. Longitudinal monitoring of the changes in liver stiffness by ElastPQ showed that early splenectomy (especially F1) may delay liver fibrosis progression. ElastPQ is an available, convenient, objective and non-invasive technique for assessing liver stiffness in rabbits with CCl 4 -induced liver fibrosis. In addition, liver stiffness measurements using ElastPQ can dynamically monitor the changes in liver stiffness in rabbit models, and in patients, after splenectomy.

  19. Variations in CCL3L gene cluster sequence and non-specific gene copy numbers

    Directory of Open Access Journals (Sweden)

    Edberg Jeffrey C

    2010-03-01

    Full Text Available Abstract Background Copy number variations (CNVs of the gene CC chemokine ligand 3-like1 (CCL3L1 have been implicated in HIV-1 susceptibility, but the association has been inconsistent. CCL3L1 shares homology with a cluster of genes localized to chromosome 17q12, namely CCL3, CCL3L2, and, CCL3L3. These genes are involved in host defense and inflammatory processes. Several CNV assays have been developed for the CCL3L1 gene. Findings Through pairwise and multiple alignments of these genes, we have shown that the homology between these genes ranges from 50% to 99% in complete gene sequences and from 70-100% in the exonic regions, with CCL3L1 and CCL3L3 being identical. By use of MEGA 4 and BioEdit, we aligned sense primers, anti-sense primers, and probes used in several previously described assays against pre-multiple alignments of all four chemokine genes. Each set of probes and primers aligned and matched with overlapping sequences in at least two of the four genes, indicating that previously utilized RT-PCR based CNV assays are not specific for only CCL3L1. The four available assays measured median copies of 2 and 3-4 in European and African American, respectively. The concordance between the assays ranged from 0.44-0.83 suggesting individual discordant calls and inconsistencies with the assays from the expected gene coverage from the known sequence. Conclusions This indicates that some of the inconsistencies in the association studies could be due to assays that provide heterogenous results. Sequence information to determine CNV of the three genes separately would allow to test whether their association with the pathogenesis of a human disease or phenotype is affected by an individual gene or by a combination of these genes.

  20. Non-invasive evaluation of liver stiffness after splenectomy in rabbits with CCl4-induced liver fibrosis

    OpenAIRE

    Wang, Ming-Jun; Ling, Wen-Wu; Wang, Hong; Meng, Ling-Wei; Cai, He; Peng, Bing

    2016-01-01

    AIM To investigate the diagnostic performance of liver stiffness measurement (LSM) by elastography point quantification (ElastPQ) in animal models and determine the longitudinal changes in liver stiffness by ElastPQ after splenectomy at different stages of fibrosis. METHODS Liver stiffness was measured in sixty-eight rabbits with CCl4-induced liver fibrosis at different stages and eight healthy control rabbits by ElastPQ. Liver biopsies and blood samples were obtained at scheduled time points...

  1. Immunohistochemical Analysis of Platelet Extract Effects on Liver Injury Induced by CCl4 in Male Rats

    OpenAIRE

    Zahra Hesami; Maryam Ayatollahi; Bita Geramizadeh; Akram Jamshidzadeh; Akbar Vahdati

    2016-01-01

    Backgrounds & objectives: Liver damage results in a large accumulation of external cellular matrix that affects the function of this important body organ in a long term and finally stops its function completely. The growth factors existing in platelet extract are more cost-effective, available, and stable than recombinant ones. To determine whether the platelet extract effects on histological changes in liver injury induced by carbon tetrachloride (CCl4), we used immunohistochemical analysis ...

  2. Comparison of chemokines (CCL-5 and SDF-1), chemokine receptors (CCR-5 and CXCR-4) and IL-6 levels in patients with different severities of depression.

    Science.gov (United States)

    Ogłodek, Ewa A; Szota, Anna; Just, Marek J; Moś, Danuta; Araszkiewicz, Aleksander

    2014-10-01

    Depression can be perceived as a psychoneuroimmunological disorder in which cytokines affecting the body's neurochemical and neuroendocrine functions play an important role. Among cytokines, chemokines participating in activation of the inflammatory response are considered to be crucial. 160 men and women were enrolled in the study. 120 of them were diagnosed with various types of depression. The mean age was 45.2 ± 4.5 years (range: 19-47 years). The control group consisted of 40 healthy individuals. The average age in this group was 42.4 ± 4.1 years. Plasma levels of chemokines and their receptors (CCL-5 - RANTES and CXCR-5, SDF-1 and CXCR-4), as well as of IL-6, were assessed by ELISA. There was an increase in SDF-1 and CCL-5 levels in women and men with different severities of depression, versus the control group. Also, an increase in the IL-6 levels, CXCR4 and CCR-5 receptors was observed in both women and men with all types of depression. Levels of SDF-1 and CCL-5 chemokines, as well as of CCR-5 and CXCR4 chemokine receptors, were higher in women than in men. The results of this study indicate the need for assessment of CCL-5 and SDF-1 chemokines levels, as they are likely markers of developing depression. Early measurement of these chemokines levels may be helpful in choosing the best pharmacotherapy. Copyright © 2014 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  3. Polyphenolic screening and protective properties of some vegetables against CCl4 liver damage

    International Nuclear Information System (INIS)

    Salawu, S.O.; Akindahunsi, A.A.

    2007-12-01

    In the present study, we screened for the polyphenolic compounds present in some selected tropical vegetables and the protective effect of the vegetable extract against CCl 4 -induced hepatotoxicity in rats as a way of evaluating their medicinal potential in addition to their nutritional values. The use of HPLC/DAD/MS revealed the presence of some phenolic compounds in the studied vegetables. Crassocephalum crepidioides; caffeoyl derivatives, Talinum triangulare; rutin and kaempferol derivatives, Amaranthus hybridus; caffeoyl derivative, rutin and kaempferol derivative, Hibiscus esculentus; caffeoyl derivative, quercetin derivative and an unidentified flavonoid, Xanthosoma mafaffa; six unidentified flavonoids with similar absorption maximum at different retention times) and Celocia argentia (luteolin derivative and four unidentified flavonoids. Carbon tetrachloride at a dose of 0.5ml/kg body weight (b.w) produced liver damage in rats as manifested by the rise in the levels of ALT (IU/l), AST (IU/l) and total protein (g/l) in the serum (40.60 ± 3.50, 80.60 ± 5.10, 73.20 ± 1.87), in the liver homogenate (1300.00 ± 7.38, 1660.00 ± 13.69, 250.00 ± 7.51) and MDA content (nmol TBARS/mg Liver Protein) in the liver homogenate (82.00 ± 0.02, 82.00 ± 0.07) compared to the control. The result revealed a reduction of the serum marker enzymes (ALT, AST and Total protein), compared with the CCl 4 treated group after the administration of the various polyphenolic extract. In a similar manner, the extract brings about a reduction of the MDA content. It could be concluded that the protective properties exhibited by the vegetables could be amongst other factor due to the presence of some polyphenols. (author)

  4. Effect of parsley (Petroselinum crispum (Mill.) Nym. ex A.W. Hill, Apiaceae) extracts on some biochemical parameters of oxidative stress in mice treated with CCl(4).

    Science.gov (United States)

    Popović, Mira; Kaurinović, Biljana; Jakovljević, Vida; Mimica-Dukic, Neda; Bursać, Marija

    2007-08-01

    The in vitro and in vivo antioxidant activity of different extracts of leaves and root of parsley (Petroselinum crispum (Mill.) Nym. ex A.W. Hill, Apiaceae) were studied. Free radical scavenging capacity (RSC) was evaluated measuring the scavenging activity on the 2,2-diphenyl-1-picrylhydrazil (DPPH) and OH radicals. Also, the effects on lipid peroxidation (LP) were evaluated. The results obtained showed that all examined extracts act as good scavengers of DPPH and OH radicals and reduce the intensity of LP. The in vivo effects were evaluated on some antioxidant systems (activities of LPx, GSH-Px, Px, CAT and XOD, and GSH content) in the mice liver and blood after treatment with the examined parsley extracts, or in combination with carbon tetrachloride (CCl(4)). On the basis of the results obtained it can be concluded that the examined extracts exhibited a certain protective effect. However, combined treatments with CCl(4) and the examined extracts showed both positive and negative synergism, inducing or suppressing the influence of CCl(4) alone. (c) 2007 John Wiley & Sons, Ltd.

  5. Local elevation of CCL22: A new trend in immunotherapy (skin model

    Directory of Open Access Journals (Sweden)

    Omer Yahia Elhussein Mohamed

    2016-11-01

    Full Text Available Many evidences supported the suggestion that one of the reasons for the failure of immunosuppressant like Corticosteroides, Calcinurine inhibitors and VitD3 in reestablishing skin immune tolerance is relying on inhibition of CCL22 expression from skin dendritic cells. Inhibition of CCL22 decreases CD4+ CD25+ FoxP3+ regulatory T cells homing to macular area and reduces the suppression capacity of these cells that make a sort of an imbalance between effector and regulatory T cells. Addition of CCL22 into the skin lesion from external sources could change the ratio between effector and regulatory T cells which dramatically alter immune system and reestablish immune tolerance. This action can't be established by the later immunosuppressant (e.g. corticosteroids and calcinurine inhibitors alone which give CCL22 an important role in the treatment of skin autoimmune and graft rejection diseases.

  6. Amelioration effects against N-nitrosodiethylamine and CCl(4)-induced hepatocarcinogenesis in Swiss albino rats by whole plant extract of Achyranthes aspera.

    Science.gov (United States)

    Kartik, R; Rao, Ch V; Trivedi, S P; Pushpangadan, P; Reddy, G D

    2010-12-01

    The prevalence of oxidative stress may be implicated in the etiology of many pathological conditions. Protective antioxidant action imparted by many plant extracts and plant products make them a promising therapeutic drug for free-radical-induced pathologies. In this study, we assessed the antioxidant potential and suppressive effects of Achyranthes aspera by evaluating the hepatic diagnostic markers on chemical-induced hepatocarcinogenesis. The in vivo model of hepatocarcinogenesis was studied in Swiss albino rats. Experimental rats were divided into five groups: control, positive control (NDEA and CCl(4)), A. aspera treated (100, 200, and 400 mg/kg b.w.). At 20 weeks after the administration of NDEA and CCl(4), treated rats received A. aspera extract (AAE) at a dose of 100, 200, and 400 mg/kg once daily route. At the end of 24 weeks, the liver and relative liver weight and body weight were estimated. Lipid peroxidation (LPO), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST), and reduced glutathione (GSH) were assayed. The hepatic diagnostic markers namely serum glutamic oxaloacetic transminase (AST), serum glutamic pyruvate transminase (ALT), serum alkaline phosphatase (ALP), gamma glutamyl transpeptidase (GGT), and bilirubin (BL) were also assayed, and the histopathological studies were investigated in control, positive control, and experimental groups. The extract did not show acute toxicity and the per se effect of the extract showed decrease in LPO, demonstrating antioxidant potential and furthermore no change in the hepatic diagnosis markers was observed. Administration of AAE suppressed hepatic diagnostic and oxidative stress markers as revealed by decrease in NDEA and CCl(4) -induced elevated levels of SGPT, SGOT, SALP, GGT, bilirubin, and LPO. There was also a significant elevation in the levels of SOD, CAT, GPx, GST, and GSH as observed after AAE treatment. The liver and relative liver weight were

  7. Flavanones from Sedum sarmentosum Bunge Alleviate CCl4-Induced Liver Fibrosis in Rats by Targeting TGF-β1/TβR/Smad Pathway In Turn Inhibiting Epithelial Mesenchymal Transition

    Directory of Open Access Journals (Sweden)

    Yuancan Lin

    2018-01-01

    Full Text Available Objective. The aim of the study is to evaluate the therapeutic effects of flavanones from Sedum sarmentosum Bunge (FSSB on CCl4-induced liver fibrosis in rats and the underlying mechanisms of action. Methods. An experimental model of liver fibrosis was established by subcutaneous injection of rats with CCl4 (40% v/v, 3 ml/kg twice per week for six weeks. FSSB (100, 200, and 400 mg/kg was intragastrically administered once per day consecutively for five weeks. Results. Our results showed that FSSB significantly attenuated CCl4-induced liver fibrosis as evidenced by reducing the elevated levels of serum biochemical indexes and improving the histological changes, including decreasing the elevation in serum alanine transaminase (ALT, aspartate transaminase (AST, hyaluronic acid (HA, and laminin (LN level, reducing infiltration of inflammatory cells and collagen fibers in liver tissue. In addition, compared to the model group, FSSB markedly downregulated the protein and mRNA expression of TGF-β1, TGF-β1 receptors I and II (TβRI and TβRII, Smad2, Smad3, and Vimentin in liver tissue, at the mean time upregulating the expression of Smad7 and E-cadherin. Conclusions. The results suggest that FSSB alleviated CCl4-induced liver fibrosis probably through inhibition of TGF-β/TβR/Smad pathway in turn inhibiting epithelial mesenchymal transition.

  8. Vapor pressure isotope effect in 13CClF3/12CClF3 by cryogenic distillation kinetics

    International Nuclear Information System (INIS)

    Wieck, H.J.; Ishida, T.

    1975-08-01

    The vapor pressure of 13 CClF 3 relative to the vapor pressure of 12 CClF 3 was measured as a function of temperature between 169 0 and 206 0 K by using a modified Bigeleisen distillation column. The transient build-up of the isotopic concentration gradient along the length of the packed column during the start-up period was monitored by taking samples from the condenser section as a function of time. The gaseous samples were completely oxidized to carbon dioxide in the presence of a platinum catalyst and a large excess of oxygen at temperatures between 1050 and 1100 0 C. The combustion products were purified by means of gas chromatography, and the purified carbon dioxide samples were analyzed in a Nier-type isotope-ratio mass spectrometer. The data of each distillation run were reduced in the light of Cohen's theory of the kinetics of square cascade of close-separation stages. The vapor pressure isotope effect for the carbon substitution in CClF 3 at temperatures between 169 0 and 206 0 K was found to be an inverse effect and to be rather insensitive to changes in temperature. The relative vapor pressure may be expressed 1n(P'/P) = [(1.5 +- 14.1)/T 2 ] - [(0.159 +- 0.076)/T], or 1n(P'/P) = [(0.173 +- 0.098)/T] - [(0.11 +- 0.53) x 10 -3 ], where P' and P are the vapor pressures of 12 CClF 3 and 13 CClF 3 , respectively. To the first-order, the presence of chlorine isotopes would not affect the fractionation of carbon isotopes by the distillation of CClF 3

  9. Significance of CCL2, CCL5 and CCR2 polymorphisms for adverse prognosis of Japanese encephalitis from an endemic population of India.

    Science.gov (United States)

    Chowdhury, Purvita; Khan, Siraj Ahmed

    2017-10-20

    Japanese encephalitis (JE) is a major contributor for viral encephalitis in Asia. Vaccination programme has limited success for largely populated JE endemic countries like India and disease exposure is unavoidable. Involvement of chemokines and its co-receptors for adverse prognosis of JE have been documented both in vitro and in vivo. Identification of the genetic predisposing factor for JE infection in humans is crucial but not yet established. Therefore, we investigated the association of single nucleotide polymorphisms (SNPs) in chemokines (CCL2 and CCL5) and its co-receptors (CCR2 and CCR5) with their protein level for JE. The study enrolled 87 symptomatic JE cases (mild: severe = 24:63) and 94 asymptomatic controls. Our study demonstrated that CCL2 (rs1024611G), CCL5 (rs2280788G) and CCR2 (rs1799864A) significantly associated with JE (Odds ratio = 1.63, 2.95 and 2.62, respectively and P = 0.045, P = 0.05 and P = 0.0006, respectively). The study revealed that rs1024611G allele was associated with elevated level of CCL2. CCL5 elevation associated with JE mortality having a Cox proportional hazard of 1.004 (P = 0.033). In conclusion, SNPs of chemokine viz. CCL2 (rs1024611G) and its receptor CCR2 (rs1799864A) significantly associated with JE which may serve as possible genetic predisposing factor and CCL5 protein level may act as marker for disease survival.

  10. Application of gas chromatography to the study of the chemical effects produced by the radiolysis and the 35Cl(n,p)35S reaction on the CCl4

    International Nuclear Information System (INIS)

    Davila R, J.I.

    1980-01-01

    In this work the gas radiochromatography, which is essential in the hot atom chemistry is used. By means of this technique the chemical effects of the 35 Cl(n,p) 35 S, and the radiolysis of liquid CCl 4 were studied. The samples of liquid CCl 4 were capsulated in cuarzo bulbs and were deaereated by several cycles of freeze and pumping in a vacuum line. The sample's irradiation was made in the Triga Mark III Salazar reactor with an approximated flux of 10 12 n-cm 2 -s -1 during ten hours. The sample's analysis was made using a gas radiochromatographer composed of a gas chromatographer, proportional flux detector and an adequate electronic system. In this form were obtained the radiochromatographics of the 35 S labelled compounds possibly formed by hot atom chemistry and at the same time the hexachloroetane formed by the secondary radiolytic effect of the ionizing radiation on the CCl 4 was identified. (author)

  11. Atmospheric Histories (1765-2015) for CFC-11, CFC-12, CFC-113, CCl4, SF6 and N2O (NCEI Accession 0164584)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The initiation of global atmospheric monitoring programs for CFC-11, CFC-12, CFC-113 and CCl4 began in the late 1970's and early 1980's. Atmospheric concentrations...

  12. CCL5 promotes proliferation of MCF-7 cells through mTOR-dependent mRNA translation

    International Nuclear Information System (INIS)

    Murooka, Thomas T.; Rahbar, Ramtin; Fish, Eleanor N.

    2009-01-01

    The proliferative capacity of cancer cells is regulated by factors intrinsic to cancer cells and by secreted factors in the microenvironment. Here, we investigated the proto-oncogenic potential of the chemokine receptor, CCR5, in MCF-7 breast cancer cell lines. At physiological levels, CCL5, a ligand for CCR5, enhanced MCF-7.CCR5 proliferation. Treatment with the mTOR inhibitor, rapamycin, inhibited this CCL5-inducible proliferation. Because mTOR directly modulates mRNA translation, we investigated whether CCL5 activation of CCR5 leads to increased translation. CCL5 induced the formation of the eIF4F translation initiation complex through an mTOR-dependent process. Indeed, CCL5 initiated mRNA translation, shown by an increase in high-molecular-weight polysomes. Specifically, we show that CCL5 mediated a rapid up-regulation of protein expression for cyclin D1, c-Myc and Dad-1, without affecting their mRNA levels. Taken together, we describe a mechanism by which CCL5 influences translation of rapamycin-sensitive mRNAs, thereby providing CCR5-positive breast cancer cells with a proliferative advantage.

  13. Effect of budesonide and cetirizine hydrochloride on neurotrophic factor, airway function and chemokines CCL17 and CCL22 in patients with allergic rhinitis

    Directory of Open Access Journals (Sweden)

    Xiang Xu

    2017-11-01

    Full Text Available Objective: To investigate the effect of budesonide combined with cetirizine hydrochloride on neurotrophic factor, airway function and chemokines CCL17 and CCL12 in patients with allergic rhinitis. Methods: A total of 123 patients with Allergic Rhinitis were randomly divided into three groups, A group treated with budesonide nasal spray, B group treated with cetirizine hydrochloride, C group treated with budesonide combined with cetirizine hydrochloride, then the Neurotrophic factors, airway function indexes and chemokines CCL17 and CCL12 levels in three groups were compared. Results: Before the treatments, the three groups of patients in neurotrophic factor, airway function index and chemokines CCL17, CCL22 have no differences, Compared with before the treatments, after receiving different treatments, the three groups of patients in all indicators were Showed significant differences. In the indexes of neurotrophic factor (NGF, BDNF, NT-3mRNA expression, there was no significant difference between group A and group B, and group C was lower than group A and B. In airway function indexes (FVC, FEV1 and PEF, A group was significantly higher than B group, C group was significantly higher than A group; In the chemokines CCL17 and CCL22 indicators, C group was lower than A group, A group was lower than B group, the difference was significant. Conclusions: Budesonide combined with cetirizine hydrochloride in the treatment of Allergic Rhinitis, can effectively control the patients' neurotrophic factor, pulmonary ventilation and chemokine CC17, CCL22 indicators, the effect is better than Budesonide alone or Cetirizine hydrochloride.

  14. Kaposi sarcoma-associated herpes virus targets the lymphotactin receptor with both a broad spectrum antagonist vCCL2 and a highly selective and potent agonist vCCL3

    DEFF Research Database (Denmark)

    Lüttichau, Hans R; Johnsen, Anders H; Jurlander, Jesper

    2007-01-01

    virus (KSHV) encodes three chemokine-like proteins named vCCL1, vCCL2, and vCCL3. In this study vCCL3 was probed in parallel with vCCL1 and vCCL2 against a panel of the 18 classified human chemokine receptors. In calcium mobilization assays vCCL1 acted as a selective CCR8 agonist, whereas vCCL2......Large DNA viruses such as herpesvirus and poxvirus encode proteins that target and exploit the chemokine system of their host. These proteins have the potential to block or change the orchestrated recruitment of leukocytes to sites of viral infection. The genome of Kaposi sarcoma-associated herpes...... was found to act as a broad spectrum chemokine antagonist of human chemokine receptors, including the lymphotactin receptor. In contrast vCCL3 was found to be a highly selective agonist for the human lymphotactin receptor XCR1. The potency of vCCL3 was found to be 10-fold higher than the endogenous human...

  15. The protective effects of aqueous extracts of wild-growing and fermented Royal Sun mushroom, Agaricus brasiliensis S. Wasser et al. (higher basidiomycetes), in CCl4-induced oxidative damage in rats.

    Science.gov (United States)

    Zhang, Chunjing; Han, Chunchao; Zhao, Baosheng; Yu, Haitao

    2012-01-01

    Culinary-medicinal Royal Sun mushroom, Agaricus brasiliensis (AbS), has traditionally been used for the prevention of a range of diseases, including cancer, hepatitis, atherosclerosis, hypercholesterolemia, diabetes, and dermatitis. The hepatoprotective effect of the fermented mushroom of A. brasiliensis (FMAE) and wild-growing A. brasiliensis (WMAE) were studied in this paper. An in vivo study of carbon tetrachloride (CCl4)-induced antioxidant activity in 2-month-old rats was conducted by examining the levels of activities of alanine aminotransaminase (ALT) and aspartate aminotransaminase (AST) and the antioxidant enzymes, including glutathione peroxidase (GSHPx) and catalase (CAT). Rats were divided into four groups, each containing six rats. The first group served as a control group. The second group was the CCl4 group. Group I and group II were treated orally with distilled water for 14 days respectively. Group III and Group IV were treated orally by WMAE and FMAE at oral doses of 50 mg/kg-day, respectively. Both WMAE and FMAE could reduce CCl4-induced toxicity, particularly hepatotoxicity, by suppressing ALT and AST activities, and increasing antioxidant enzyme activity. The studies demonstrate that both the fermented and wild-growing A. brasiliensis could protect the liver against CCl4-induced oxidative damage in rats.

  16. Adipose derived mesenchymal stem cells transplantation via portal vein improves microcirculation and ameliorates liver fibrosis induced by CCl4 in rats

    Directory of Open Access Journals (Sweden)

    Wang Yu

    2012-06-01

    Full Text Available Abstract Introduction Adipose derived mesenchymal stem cells (ADMSCs, carrying the similar characteristics to bone marrow mesenchymal stem cells, only much more abundant and easier to obtain, may be a promising treatment for liver fibrosis. We aim to investigate the therapeutic potential of ADMSCs transplantation in liver fibrosis caused by carbon tetrachloride (CCl4 in rats as well as its underlying mechanism, and to further explore the appropriate infusion pathway. Methods ADMSCs were isolated, cultured and identified. Placebo and ADMSCs were transplanted via portal vein and tail vein respectively into carbon tetrachloride (CCl4-induced liver fibrosis rats. Computed tomography (CT perfusion scan and microvessel counts were performed to measure the alteration of liver microcirculation after therapy. Liver function tests and histological findings were estimated. Results CT perfusion scan shown significant decrease of hepatic arterial perfusion index, significant increased portal vein perfusion, total liver perfusion in rats receiving ADMSCs from portal vein, and Factor VIII (FVIII immunohistochemical staining shown significant decrease of microvessels in rats receiving ADMSCs from portal vein, indicating microcirculation improvement in portal vein group. Vascular endothelial growth Factor (VEGF was significantly up-regulated in fibrosis models, and decreased after ADMSCs intraportal transplantation. A significant improvement of liver functional test and histological findings in portal vein group were observed. No significance was found in rats receiving ADMSCs from tail vein. Conclusions ADMSCs have a therapeutic effect against CCl4-mediated liver fibrosis. ADMSCs may benefit the fibrotic liver through alteration of microcirculation, evidenced by CT perfusion scan and down-regulation of VEGF. Intraportal transplantation is a better pathway than tail vein transplantation.

  17. Amelioration effects against N-nitrosodiethylamine and CCl4-induced hepatocarcinogenesis in Swiss albino rats by whole plant extract of Achyranthes aspera

    Science.gov (United States)

    Kartik, R.; Rao, Ch. V.; Trivedi, S.P.; Pushpangadan, P.; Reddy, G.D.

    2010-01-01

    Objective: The prevalence of oxidative stress may be implicated in the etiology of many pathological conditions. Protective antioxidant action imparted by many plant extracts and plant products make them a promising therapeutic drug for free-radical-induced pathologies. In this study, we assessed the antioxidant potential and suppressive effects of Achyranthes aspera by evaluating the hepatic diagnostic markers on chemical-induced hepatocarcinogenesis. Materials and Methods: The in vivo model of hepatocarcinogenesis was studied in Swiss albino rats. Experimental rats were divided into five groups: control, positive control (NDEA and CCl4), A. aspera treated (100, 200, and 400 mg/kg b.w.). At 20 weeks after the administration of NDEA and CCl4, treated rats received A. aspera extract (AAE) at a dose of 100, 200, and 400 mg/kg once daily route. At the end of 24 weeks, the liver and relative liver weight and body weight were estimated. Lipid peroxidation (LPO), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST), and reduced glutathione (GSH) were assayed. The hepatic diagnostic markers namely serum glutamic oxaloacetic transminase (AST), serum glutamic pyruvate transminase (ALT), serum alkaline phosphatase (ALP), gamma glutamyl transpeptidase (GGT), and bilirubin (BL) were also assayed, and the histopathological studies were investigated in control, positive control, and experimental groups. Results: The extract did not show acute toxicity and the per se effect of the extract showed decrease in LPO, demonstrating antioxidant potential and furthermore no change in the hepatic diagnosis markers was observed. Administration of AAE suppressed hepatic diagnostic and oxidative stress markers as revealed by decrease in NDEA and CCl4 -induced elevated levels of SGPT, SGOT, SALP, GGT, bilirubin, and LPO. There was also a significant elevation in the levels of SOD, CAT, GPx, GST, and GSH as observed after AAE treatment. The

  18. Comparison of the Hepatoprotective Effects of Four Endemic Cirsium Species Extracts from Taiwan on CCl4-Induced Acute Liver Damage in C57BL/6 Mice

    Directory of Open Access Journals (Sweden)

    Zi-Wei Zhao

    2018-04-01

    Full Text Available Species of Cirsium (Asteraceae family have been used in folk hepatoprotective medicine in Taiwan. We collected four Cirsium species—including the aerial part of Cirsium arisanense (CAH, the aerial part of Cirsium kawakamii (CKH, the flower part of Cirsium japonicum DC. var. australe (CJF, and Cirsii Herba (CH—and then made extractions from them with 70% methanol. We compared the antioxidant contents and activities of these four Cirsium species extracts by a spectrophotometric method and high-performance liquid chromatography–photodiode array detector (HPLC-DAD. We further evaluated the hepatoprotective effects of these extracts on CCl4-induced acute liver damage in C57BL/6 mice. The present study found CAH possesses the highest antioxidant activity among the four Cirsium species, and these antioxidant activities are closely related to phenylpropanoid glycoside (PPG contents. The extracts decreased serum ALT and AST levels elevated by injection with 0.2% CCl4. However, only CJF and CH decreased hepatic necrosis. Silibinin decreased serum alanine aminotransferase (ALT and aspartate aminotransferase (AST levels and hepatic necrosis caused by CCl4. CJF and CH restored the activities of hepatic antioxidant enzymes and decreased hepatic malondialdehyde (MDA levels. CJF further restored the expression of hepatic antioxidant enzymes including Cu/Zn-superoxide dismutase (Cu/Zn-SOD, Mn-superoxide dismutase (Mn-SOD, and glutathione S-transferase (GST proteins. HPLC chromatogram indicated that CKH, CJF, and CH contained silibinin diastereomers (α and β. Only CJF contained diosmetin. Hence, the hepatoprotective mechanism of CJF against CCl4-induced acute liver damage might be involved in restoring the activities and protein expression of the hepatic antioxidant defense system and inhibiting hepatic inflammation, and these hepatoprotective effects are related to the contents of silibinin diastereomers and diosmetin.

  19. Contribution of dot-blot assay to the diagnosis and management of myositis: a three-year practice at a university hospital centre.

    Science.gov (United States)

    Martel, Clothilde; Vignaud, Guillaume; Liozon, Eric; Magy, Laurent; Gallouedec, Gael; Ly, Kim; Bezanahary, Holly; Cypierre, Anne; Lapébie, François-Xavier; Palat, Sylvain; Gondran, Guillaume; Jauberteau, Marie-Odile; Fauchais, Anne-Laure

    2016-01-01

    Idiopathic inflammatory myopathies (IIM) are heterogeneous autoimmune diseases with wide clinical spectrum that may lead to delayed diagnosis. The aim of this study was to examine the impact of IIM-specific dot-blot assay on diagnostic process of patients presenting with muscular or systemic symptoms evocating of IIM. We collected all the prescriptions of an IIM specific dot-blot assay (8 autoantigens including Jo-1, PL-7, PL-12, SRP, Mi-2, Ku, PM/Scl and Scl-70) over a 38-month period. 316 myositis dot-blot assays (MSD) were performed in 274 patients (156 women, mean age 53±10.6 years) referring for muscular and/or systemic symptoms suggesting IIM. The timing of dot prescription through the diagnostic process was highly variable: without (35%), concomitantly (16%) or after electromyographic studies (35%). Fifty-nine patients (22%) had IIM according to Bohan and Peter's criteria. Among them, 29 (49%) had positive dot (8 Jo-1, 6 PM-Scl, 5 PL-12, 5 SRP, 2 Mi-2, 2 PL-7 and 1 Ku). Various other diagnoses were performed including 35 autoimmune disease or granulomatosis (12%), 19 inflammatory rheumatic disease (7%), 16 non inflammatory muscular disorders (6%), 10 drug-induced myalgia (4%), 11 infectious myositis (4%). Except 11 borderline SRP results and one transient PM-Scl, MSD was positive only in one case of IIM. Dot allowed clinicians to correct diagnosis in 4 cases and improved the diagnosis of IIM subtypes in 4 cases. This study reflects the interest of myositis dot in the rapid diagnosis process of patients with non-specific muscular symptoms leading to various diagnoses including IIM.

  20. Rac1 plays a role in CXCL12 but not CCL3-induced chemotaxis and Rac1 GEF inhibitor NSC23766 has off target effects on CXCR4.

    Science.gov (United States)

    Mills, Shirley C; Howell, Lesley; Beekman, Andrew; Stokes, Leanne; Mueller, Anja

    2018-01-01

    Cell migration towards a chemotactic stimulus relies on the re-arrangement of the cytoskeleton, which is triggered by activation of small G proteins RhoA, Rac1 and Cdc42, and leads to formation of lamellopodia and actin polymerisation amongst other effects. Here we show that Rac1 is important for CXCR4 induced chemotaxis but not for CCR1/CCR5 induced chemotaxis. For CXCL12-induced migration via CXCR4, breast cancer MCF-7 cells are reliant on Rac1, similarly to THP-1 monocytes and Jurkat T-cells. For CCL3-induced migration via CCR1 and/or CCR5, Rac1 signalling does not regulate cell migration in either suspension or adherent cells. We have confirmed the involvement of Rac1 with the use of a specific Rac1 blocking peptide. We also used a Rac1 inhibitor EHT 1864 and a Rac1-GEF inhibitor NSC23766 to probe the importance of Rac1 in chemotaxis. Both inhibitors did not block CCL3-induced chemotaxis, but they were able to block CXCL12-induced chemotaxis. This confirms that Rac1 activation is not essential for CCL3-induced migration, however NSC23766 might have secondary effects on CXCR4. This small molecule exhibits agonistic features in internalisation and cAMP assays, whereas it acts as an antagonist for CXCR4 in migration and calcium release assays. Our findings strongly suggest that Rac1 activation is not necessary for CCL3 signalling, and reveal that NSC23766 could be a novel CXCR4 receptor ligand. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.

  1. Laser capture microdissection and cDNA array analysis of endometrium identify CCL16 and CCL21 as epithelial-derived inflammatory mediators associated with endometriosis

    Directory of Open Access Journals (Sweden)

    Jones Rebecca L

    2007-05-01

    Full Text Available Abstract Background Understanding the pathophysiology of chemokine secretion in endometriosis may offer a novel area of therapeutic intervention. This study aimed to identify chemokines differentially expressed in epithelial glands in eutopic endometrium from normal women and those with endometriosis, and to establish the expression profiles of key chemokines in endometriotic lesions. Methods Laser capture microdissection isolated epithelial glands from endometrial eutopic tissue from women with and without endometriosis in the mid-secretory phase of their menstrual cycles. Gene profiling of the excised glands used a human chemokine and receptor cDNA array. Selected chemokines were further examined using real-time PCR and immunohistochemistry. Results 22 chemokine/receptor genes were upregulated and two downregulated in pooled endometrial epithelium of women with endometriosis compared with controls. CCL16 and CCL21 mRNA was confirmed as elevated in some women with endometriosis compared to controls on individual samples. Immunoreactive CCL16 and CCL21 were predominantly confined to glands in eutopic and ectopic endometrium: leukocytes also stained. Immunoreactive CCL16 was overall higher in glands in ectopic vs. eutopic endometrium from the same woman (P Conclusion This study provides novel candidate molecules and suggests a potential local role for CCL16 and CCL21 as mediators contributing to the inflammatory events associated with endometriosis.

  2. Chemokine MCP1/CCL2 and RANTES/CCL5 gene polymorphisms influence Henoch–Schönlein purpura susceptibility and severity

    Directory of Open Access Journals (Sweden)

    Hsin-Hui Yu

    2015-04-01

    Conclusion: Our results support the fact that chemokines play important roles in the pathogenesis of HSP. MCP1/CCL2 gene polymorphisms were associated with susceptibility for HSP. RANTES/CCL5 gene polymorphisms may be related to disease severity and HSP nephritis.

  3. CCL3L1-CCR5 genotype influences durability of immune recovery during antiretroviral therapy of HIV-1–infected individuals

    Science.gov (United States)

    Ahuja, Sunil K; Kulkarni, Hemant; Catano, Gabriel; Agan, Brian K; Camargo, Jose F; He, Weijing; O'Connell, Robert J; Marconi, Vincent C; Delmar, Judith; Eron, Joseph; Clark, Robert A; Frost, Simon; Martin, Jeffrey; Ahuja, Seema S; Deeks, Steven G; Little, Susan; Richman, Douglas; Hecht, Frederick M; Dolan, Matthew J

    2008-01-01

    The basis for the extensive variability seen in the reconstitution of CD4+ T cell counts in HIV-infected individuals receiving highly active antiretroviral therapy (HAART) is not fully known. Here, we show that variations in CCL3L1 gene dose and CCR5 genotype, but not major histocompatibility complex HLA alleles, influence immune reconstitution, especially when HAART is initiated at <350 CD4+ T cells/mm3. The CCL3L1-CCR5 genotypes favoring CD4+ T cell recovery are similar to those that blunted CD4+ T cell depletion during the time before HAART became available (pre-HAART era), suggesting that a common CCL3L1-CCR5 genetic pathway regulates the balance between pathogenic and reparative processes from early in the disease course. Hence, CCL3L1-CCR5 variations influence HIV pathogenesis even in the presence of HAART and, therefore, may prospectively identify subjects in whom earlier initiation of therapy is more likely to mitigate immunologic failure despite viral suppression by HAART. Furthermore, as reconstitution of CD4+ cells during HAART is more sensitive to CCL3L1 dose than to CCR5 genotypes, CCL3L1 analogs might be efficacious in supporting immunological reconstitution. PMID:18376407

  4. Attenuation of CCl4-induced hepatic fibrosis in mice by vaccinating against TGF-β1.

    Directory of Open Access Journals (Sweden)

    Xiaobao Fan

    Full Text Available Transforming growth factor β1 (TGF-β1 is the pivotal pro-fibrogenic cytokine in hepatic fibrosis. Reducing the over-produced expression of TGF-β1 or blocking its signaling pathways is considered to be a promising therapeutic strategy for hepatic fibrosis. In this study, we evaluated the feasibility of attenuating hepatic fibrosis by vaccination against TGF-β1 with TGF-β1 kinoids. Two TGF-β1 kinoid vaccines were prepared by cross-linking TGF-β1-derived polypeptides (TGF-β1(25-[41-65] and TGF-β1(30-[83-112] to keyhole limpet hemocyanin (KLH. Immunization with the two TGF-β1 kinoids efficiently elicited the production of high-levels of TGF-β1-specific antibodies against in BALB/c mice as tested by enzyme-linked immunosorbent assay (ELISA and Western blotting. The antisera neutralized TGF-β1-induced growth-inhibition on mink lung epithelial cells (Mv1Lu and attenuated TGF-β1-induced Smad2/3 phosphorylation, α-SMA, collagen type 1 alpha 2 (COL1A2, plasminogen activator inhibitor-1 (PAI-1 and tissue inhibitor of metalloproteinase-1 (TIMP-1 expression in the rat hepatic stellate cell (HSC line, HSC-T6. Vaccination against TGF-β1 with the kinoids significantly suppressed CCl4-induced collagen deposition and the expression of α-SMA and desmin, attenuated hepatocyte apoptosis and accelerated hepatocyte proliferation in BALB/c mice. These results demonstrated that immunization with the TGF-β1 kinoids efficiently attenuated CCl4-induced hepatic fibrosis and liver injury. Our study suggests that vaccination against TGF-β1 might be developed into a feasible therapeutic approach for the treatment of chronic fibrotic liver diseases.

  5. Effect of different uranium compounds on the properties of U-Pt-Y-Ba-O double-perovskite pinning centres in textured Y-Ba-Cu-O superconductor

    Energy Technology Data Exchange (ETDEWEB)

    Sawh, Ravi-Persad; Weinstein, Roy; Parks, Drew; Gandini, Alberto [Beam Particle Dynamics Laboratories, University of Houston, Houston, TX 77204-5005 (United States); Department of Physics, University of Houston, Houston, TX 77204-5005 (United States); Texas Center for Superconductivity and Advanced Materials, University of Houston, Houston, TX 77204-5005 (United States)

    2005-02-01

    An experiment was performed to test the effect of different uranium compounds on the properties of chemical pinning centres. UO{sub 2}, UO{sub 3}, and UO{sub 4}{center_dot}2H{sub 2}O wereadmixed to Y 123+Pt, and textured. Tests of J{sub c} via measurements of trapped field (B{sub trap}) indicate a clear dependence of B{sub trap} on the U compound admixed to create the pinning centres. In all three cases there is a monotonic increase in B{sub trap} as the mass (M{sub U}) of U is increased. However, the magnitude of the increase in B{sub trap} depends on the admixed U compound. The highest increase in B{sub trap} is measured in samples doped with UO{sub 4}{center_dot}2H{sub 2}O, and the lowest is obtained in samples doped with UO{sub 2}. Microstructure studies indicate that the composition of the U-rich pinning deposits is the same in all three cases, i.e. all are the previously identified (U{sub 0.6}Pt{sub 0.4})Y Ba{sub 2}O{sub 6} compound. The primary difference among the three types of samples is that the size of the U-Pt-Y-Ba-O pinning deposits depends on the admixed U compound. While all are in the nanometre domain, the diameter of these deposits was markedly larger in UO{sub 2} doped samples than in UO{sub 3} doped samples, and smallest in UO{sub 4}{center_dot}2H{sub 2}O doped samples. Because some form of poisoning limits the amount of U that can be added to create pinning centres, to M{sub U} {approx}1 wt%, smaller deposits result in a greater number of pinning centres. We conclude that UO{sub 4}{center_dot}2H{sub 2}O is more effective than either UO{sub 3} or UO{sub 2} in the formation of U-Pt-Y-Ba-O pinning centres because of diminished pinning centre size, and consequent increase in pinning centre density.

  6. Hepatoprotective and Antioxidant Effect of Hibiscus Polyphenol Rich Extract (HPE) Against Carbon Tetrachloride (CCL4) - Induced Damage in Rats

    OpenAIRE

    Adetutu, Adewale; Owoade, Abiodun O.

    2013-01-01

    Aims: Hibiscus sabdariffa is a medicinal plant that is consumed for its health benefits in Africa. The study was designed to investigate the hepatoprotective potentials of Hibiscus polyphenolic rich extract (HPE), (a group of phenolic compounds occurring in the dried calyx of Hibiscus sabdariffa) against CCl4-induced damaged in rats. Place and Duration of Study: Department of Biochemistry, Ladoke Akintola University of Technology, Ogbomosho, Nigeria, between January 2011 and June 2012. Method...

  7. TNF-α and IL-1β Dependent Induction of CCL3 Expression by Nucleus Pulposus Cells Promotes Macrophage Migration through CCR1

    Science.gov (United States)

    Wang, Jianru; Tian, Ye; Phillips, Kate L.E.; Chiverton, Neil; Haddock, Gail; Bunning, Rowena A.; Cross, Alison K.; Shapiro, Irving M.; LeMaitre, Christine L.; Risbud, Makarand V.

    2012-01-01

    Objective To investigate TNF-α and IL-1β regulation of CCL3 expression in nucleus pulposus (NP) cells and in macrophage migration. Methods qRT-PCR and immunohistochemistry were used to measure CCL3 expression in NP cells. Transfections were used to determine the role of NF-κB, C/EBP-β and MAPK on cytokine mediated CCL3 promoter activity. Effect of NP-conditioned medium on macrophage migration was measured using a transwell system. Results An increase in CCL3 expression and promoter activity was observed in NP cells after TNF-α or IL-1β treatment. Treatment of cells with NF-κB and MAPK inhibitors abolished the effect of the cytokines on CCL3 expression. The inductive effect of p65 and C/EBP-β on CCL3 promoter was confirmed through gain- and loss-of-function studies. Noteworthy, co-transfection of p50 completely blocked cytokine and p65 dependent induction. In contrast, c-Rel and RelB had little effect on promoter activity. Lentiviral transduction with Sh-p65 and Sh-Ikkβ significantly decreased TNF-α dependent increase in CCL3 expression. Analysis of degenerate human NP tissues showed that CCL3, but not CCL4 expression correlated positively with the grade of tissue degeneration. Importantly, treatment of macrophages with conditioned medium of NP cells treated with TNF-α or IL-1β promoted their migration; pretreatment of macrophages with antagonist to CCR1, primary receptor for CCL3 and CCL4, blocked cytokine mediated migration. Conclusions By controlling the activation of MAPK, NF-κB and C/EBPβ signaling, TNF-α and IL-1β modulate the expression of CCL3 in NP cells. The CCL3-CCR1 axis may play an important role in promoting macrophage infiltration in degenerate, herniated discs. PMID:23233369

  8. Regulation of CCL5 expression in smooth muscle cells following arterial injury.

    Directory of Open Access Journals (Sweden)

    Huan Liu

    Full Text Available Chemokines play a crucial role in inflammation and in the pathophysiology of atherosclerosis by recruiting inflammatory immune cells to the endothelium. Chemokine CCL5 has been shown to be involved in atherosclerosis progression. However, little is known about how CCL5 is regulated in vascular smooth muscle cells. In this study we report that CCL5 mRNA expression was induced and peaked in aorta at day 7 and then declined after balloon artery injury, whereas IP-10 and MCP-1 mRNA expression were induced and peaked at day 3 and then rapidly declined.The expression of CCL5 receptors (CCR1, 3 & 5 were also rapidly induced and then declined except CCR5 which expression was still relatively high at day 14 after balloon injury. In rat smooth muscle cells (SMCs, similar as in aorta CCL5 mRNA expression was induced and kept increasing after LPS plus IFN-gamma stimulation, whereas IP-10 mRNA expression was rapidly induced and then declined. Our data further indicate that induction of CCL5 expression in SMCs was mediated by IRF-1 via binding to the IRF-1 response element in CCL5 promoter. Moreover, p38 MAPK was involved in suppression of CCL5 and IP-10 expression in SMCs through common upstream molecule MKK3. The downstream molecule MK2 was required for p38-mediated CCL5 but not IP-10 inhibition. Our findings indicate that CCL5 induction in aorta and SMCs is mediated by IRF-1 while activation of p38 MAPK signaling inhibits CCL5 and IP-10 expression. Methods targeting MK2 expression could be used to selectively regulate CCL5 but not IP-10 expression in SMCs.

  9. TPL-2 restricts Ccl24-dependent immunity to Heligmosomoides polygyrus

    Science.gov (United States)

    Kannan, Yashaswini; Entwistle, Lewis J.; Pelly, Victoria S.; Perez-Lloret, Jimena; Ley, Steven C.

    2017-01-01

    TPL-2 (COT, MAP3K8) kinase activates the MEK1/2-ERK1/2 MAPK signaling pathway in innate immune responses following TLR, TNFR1 and IL-1R stimulation. TPL-2 contributes to type-1/Th17-mediated autoimmunity and control of intracellular pathogens. We recently demonstrated TPL-2 reduces severe airway allergy to house dust mite by negatively regulating type-2 responses. In the present study, we found that TPL-2 deficiency resulted in resistance to Heligmosomoides polygyrus infection, with accelerated worm expulsion, reduced fecal egg burden and reduced worm fitness. Using co-housing experiments, we found resistance to infection in TPL-2 deficient mice (Map3k8–/–) was independent of microbiota alterations in H. polygyrus infected WT and Map3k8–/–mice. Additionally, our data demonstrated immunity to H. polygyrus infection in TPL-2 deficient mice was not due to dysregulated type-2 immune responses. Genome-wide analysis of intestinal tissue from infected TPL-2-deficient mice identified elevated expression of genes involved in chemotaxis and homing of leukocytes and cells, including Ccl24 and alternatively activated genes. Indeed, Map3k8–/–mice had a significant influx of eosinophils, neutrophils, monocytes and Il4GFP+ T cells. Conditional knockout experiments demonstrated that specific deletion of TPL-2 in CD11c+ cells, but not Villin+ epithelial cells, LysM+ myeloid cells or CD4+ T cells, led to accelerated resistance to H. polygyrus. In line with a central role of CD11c+ cells, CD11c+ CD11b+ cells isolated from TPL-2-deficient mice had elevated Ccl24. Finally, Ccl24 neutralization in TPL-2 deficient mice significantly decreased the expression of Arg1, Retnla, Chil3 and Ear11 correlating with a loss of resistance to H. polygyrus. These observations suggest that TPL-2-regulated Ccl24 in CD11c+CD11b+ cells prevents accelerated type-2 mediated immunity to H. polygyrus. Collectively, this study identifies a previously unappreciated role for TPL-2 controlling immune

  10. Effect of Jiangzhi tablet on serum indexes of mice with fatty liver induced by CCL4

    Science.gov (United States)

    Geng, Xiuli; Kong, Xuejun; Li, Chongxian; Hao, Shaojun; Wang, Hongyu; Chen, Weiliang; Zhang, Zhengchen

    2018-04-01

    To investigate the effect of Jiangzhi tablet on serum indexes of mice with fatty liver induced by CCL4, 60 mice were randomly divided into blank control group, model group, positive group, high, middle and low dose group. High fat diet fed mice for 2 weeks, in second the beginning of the weekend, each group of experimental animal except the blank group in the afternoon 1:00 subcutaneous injection of 40% CCl4 of edible oil (0.05 mL/10g, 2 times / week) for modeling; at the same time, 9:00 in the morning to lipid-lowering tablets LARGEMEDTUM and small dose group (0.1125g/ml, 0.05625g/ml, 0.02815g/ml) and Gantai tablet group (0.045g/ml) mice fed with corresponding drugs, the model group received the same volume of physiological saline. At the end of the fifth week, the eyeballs were collected and the serum was separated. The levels of serum triglyceride, high density lipoprotein, low density lipoprotein, serum AST, ALT and ALP were detected. Compared with the model group, Dongbao Gantai group, Jiangzhi tablets, high dose group had significantly decreased TG and LDL content in serum of mice (ptablets low dose group can significantly reduce TG and LDL content in serum (ptablet high dose group and middle dose group could significantly reduce the content of ALT, ALP, AST in serum of mice (ptablets in small dose group can significantly reduce ALP and AST content in serum (ptablets have a better intervention effect on the mice model of fatty liver induced by small dose of carbon tetrachloride.

  11. Why are SiX5(-) and GeX5(-) (X = F, Cl) stable but not CF5(-) and CCl5(-)?

    Science.gov (United States)

    Marchaj, Marzena; Freza, Sylwia; Skurski, Piotr

    2012-03-01

    The possible existence of the CF(5)(-), CCl(5)(-), SiF(5)(-), SiCl(5)(-), GeF(5)(-), and GeCl(5)(-) anions has been investigated using ab initio methods. The species containing Si and Ge as central atoms were found to adopt the D(3h)-symmetry trigonal bipyramidal equilibrium structures whose thermodynamic stabilities were confirmed by examining the most probable fragmentation channels. The ab initio re-examination of the electronic stabilities of the SiF(5)(-), SiCl(5)(-), GeF(5)(-), and GeCl(5)(-) anions [using the OVGF(full) method with the 6-311+G(3df) basis set] led to the very large vertical electron detachment (VDE) energies of 9.316 eV (SiF(5)(-)) and 9.742 eV (GeF(5)(-)), whereas smaller VDEs of 6.196 and 6.452 eV were predicted for the SiCl(5)(-) and GeCl(5)(-) species, respectively. By contrast, the high-symmetry and structurally compact anionic CF(5)(-) and CCl(5)(-) systems cannot exist due to the strongly repulsive potential predicted for the X(-) (F(-) or Cl(-)) approaching the CX(4) (CF(4) or CCl(4)). The formation of weakly bound CX(4)···X(-) (CF(4)···F(-) and CCl(4)···Cl(-)) anionic complexes (consisting of pseudotetrahedral neutral CX(4) with the weakly tethered X(-)) might be expected at low temperatures (approaching 0 K), whereas neither CX(5)(-) (CF(5)(-), CCl(5)(-)) systems nor CX(4)···X(-) (CF(4)···F(-) and CCl(4)···Cl(-)) complexes can exist in the elevated temperatures (above 0K) due to their susceptibility to the fragmentation (leading to the X(-) loss). © 2012 American Chemical Society

  12. CCL5 and CCR5 interaction promotes cell motility in human osteosarcoma.

    Directory of Open Access Journals (Sweden)

    Shih-Wei Wang

    Full Text Available BACKGROUND: Osteosarcoma is characterized by a high malignant and metastatic potential. CCL5 (previously called RANTES was originally recognized as a product of activated T cells, and plays a crucial role in the migration and metastasis of human cancer cells. It has been reported that the effect of CCL5 is mediated via CCR receptors. However, the effect of CCL5 on migration activity and integrin expression in human osteosarcoma cells is mostly unknown. METHODOLOGY/PRINCIPAL FINDINGS: Here we found that CCL5 increased the migration and expression of αvβ3 integrin in human osteosarcoma cells. Stimulation of cells with CCL5 increased CCR5 but not CCR1 and CCR3 expression. CCR5 mAb, inhibitor, and siRNA reduced the CCL5-enhanced the migration and integrin up-regulation of osteosarcoma cells. Activations of MEK, ERK, and NF-κB pathways after CCL5 treatment were demonstrated, and CCL5-induced expression of integrin and migration activity was inhibited by the specific inhibitor and mutant of MEK, ERK, and NF-κB cascades. In addition, over-expression of CCL5 shRNA inhibited the migratory ability and integrin expression in osteosarcoma cells. CONCLUSIONS/SIGNIFICANCE: CCL5 and CCR5 interaction acts through MEK, ERK, which in turn activates NF-κB, resulting in the activations of αvβ3 integrin and contributing the migration of human osteosarcoma cells.

  13. Electron paramagnetic resonance and optical absorption study of V{sup 4+} centres in YVO{sub 4} crystals

    Energy Technology Data Exchange (ETDEWEB)

    Garces, N Y [Department of Physics, West Virginia University, Morgantown, WV 26506 (United States); Stevens, K T [Northrop Grumman Space Technology, Synoptics, Charlotte, NC 28273 (United States); Foundos, G K [Northrop Grumman Space Technology, Synoptics, Charlotte, NC 28273 (United States); Halliburton, L E [Department of Physics, West Virginia University, Morgantown, WV 26506 (United States)

    2004-10-06

    Electron paramagnetic resonance (EPR) has been used to characterize three distinct V{sup 4+} centres in undoped Czochralski-grown yttrium orthovanadate (YVO{sub 4}) crystals. These EPR signals are observed at low temperatures, and their average c-axis splittings between adjacent {sup 51}V hyperfine lines are 40 G, 123 G, and 140 G. We refer to these centres as [V{sup 4+}]{sub A}, [V{sup 4+}]{sub B}, and [V{sup 4+}]{sub C}, respectively. The [V{sup 4+}]{sub A} and [V{sup 4+}]{sub B} centres are present in as-grown crystals. Exposure at 77 K to ionizing radiation (x-rays or an ultraviolet laser beam) destroys these centres and creates the [V{sup 4+}]{sub C} centres. The as-grown state of the crystal is restored upon returning to room temperature. Angular dependence data are used to determine the principal values and principal directions of the g tensor and the {sup 51}V hyperfine tensor for each of the centres. We suggest that the [V{sup 4+}]{sub A} centre is a V{sup 4+} ion adjacent to an oxygen vacancy and that the [V{sup 4+}]{sub B} centre is a V{sup 4+} ion substituting for a Y{sup 3+} ion (i.e. a vanadium antisite defect). The [V{sup 4+}]{sub C} centre is assigned to a V{sup 4+} ion at a regular vanadium site with a nearby stabilizing defect, possibly a Zr{sup 4+} on a Y{sup 3+} site. In as-grown crystals, there is a correlation between the number of [V{sup 4+}]{sub A} centres and the intensity (at 380 nm) of a broad near-edge optical absorption band. This band, now associated with oxygen vacancies, gives YVO{sub 4} a 'yellow' appearance.

  14. Evolution of the Copper Surface in the Course of Oxidation by CCl4-L (L=THF, Dmf, Dmso): Scanning Probe Microscope Study

    Science.gov (United States)

    Panteleev, S. V.; Maslennikov, S. V.; Ignatov, S. K.; Spirina, I. V.; Kruglova, M. V.; Gribkov, B. A.; Vdovichev, S. N.

    2013-04-01

    The evolution of compact surface of the 100 nm copper film deposited on the glass-ceramics doped with vanadium coating in the course of the oxidation by the CCl4-L (L = dimethylformamide (DMF), tetrahydrofuran (THF), dimethylsulfoxide (DMSO), CCl4 concentration ≈ 1 mol/L) was studied by atomic force microscopy (AFM) in contact mode. The dynamics of active centers formation and destruction was investigated in the course of the oxidation process. The metallic sample dissolution rate was estimated as a function of the coordinating solvent nature. The development of the metal surface oxidation was established to lead to a significant increase of surface roughness. This phenomenon can be explained by the fact that different parts of the surface react at different rates. Further course of the reaction leads to a significant decrease of the surface roughness of copper films. The amount of the metal reacted has an almost linear dependence on the reaction time. AFM scans indicate that there is the same mechanism of the reaction between copper and carbon tetrachloride for all solvents.

  15. Electron-impact dissociative ionization of CClF3 and CCl3F

    International Nuclear Information System (INIS)

    Martinez, Roberto; Sierra, Borja; Basterretxea, Francisco J.; Sanchez Rayo, Maria N.; Castano, Fernando

    2006-01-01

    A crossed-beam experiment of well characterized kinetic energy (KE) electrons and supersonic halomethanes CCl 3 F and CClF 3 in Ar carrier has been carried out in order to quantify the kinetic energy distributions (KEDs), the appearance energies (AEs) and the channels involved in the production of nascent ions. The ion KEDs were derived from the band profiles of the time-of-flight mass spectrum and the total KEDs computed using conservation laws. Heavier ions are created with KED peaked at thermal energies in contrast with low mass atoms or other fragments, where the distribution is broader and the maximum is at much higher energies. A discussion of the dissociative ionization pathways derived from the appearance energies, total average KEDs, thermodynamic enthalpies and computed electron dissociation energies is reported. The role of the vibrational and rotational energies into the dissociative processes is also discussed

  16. Thermodynamic studies of aqueous and CCl4 solutions of 15-crown-5 at 298.15 K: an application of McMillan-Mayer and Kirkwood-Buff theories of solutions.

    Science.gov (United States)

    Dagade, Dilip H; Shetake, Poonam K; Patil, Kesharsingh J

    2007-07-05

    The density and osmotic coefficient data for solutions of 15-crown-5 (15C5) in water and in CCl4 solvent systems at 298.15 K have been reported using techniques of densitometry and vapor pressure osmometry in the concentration range of 0.01-2 mol kg-1. The data are used to obtain apparent molar and partial molar volumes, activity coefficients of the components as a function of 15C5 concentration. Using the literature heat of dilution data for aqueous system, it has become possible to calculate entropy of mixing (DeltaS(mix)), excess entropy of solution (DeltaS(E)), and partial molar entropies of the components at different concentrations. The results of all these are compared to those obtained for aqueous 18-crown-6 solutions reported earlier. It has been observed that the partial molar volume of 15C5 goes through a minimum and that of water goes through a maximum at approximately 1.2 mol kg(-1) in aqueous solutions whereas the opposite is true in CCl4 medium but at approximately 0.5 mol kg(-1). The osmotic and activity coefficients of 15C5 and excess free energy change for solution exhibit distinct differences in the two solvent systems studied. These results have been explained in terms of hydrophobic hydration and interactions in aqueous solution while weak solvophobic association of 15C5 molecules in CCl4 solutions is proposed. The data are further subjected to analysis by applying McMillan-Mayer and Kirkwood-Buff theories of solutions. The analysis shows that osmotic second virial coefficient value for 15C5 is marginally less than that of 18C6 indicating that reduction in ring flexibility does not affect the energetics of the interactions much in aqueous solution while the same gets influenced much in nonpolar solvent CCl4.

  17. Mutations in BALB mitochondrial DNA induce CCL20 up-regulation promoting tumorigenic phenotypes

    Energy Technology Data Exchange (ETDEWEB)

    Sligh, James [Department of Medicine—Dermatology Division, University of Arizona, Tucson, AZ 857 24 (United States); University of Arizona Cancer Center, Tucson, AZ 85724 (United States); Janda, Jaroslav [University of Arizona Cancer Center, Tucson, AZ 85724 (United States); Jandova, Jana, E-mail: jjandova@email.arizona.edu [Department of Medicine—Dermatology Division, University of Arizona, Tucson, AZ 857 24 (United States); University of Arizona Cancer Center, Tucson, AZ 85724 (United States)

    2014-11-15

    Highlights: • Alterations in mitochondrial DNA are commonly found in various human cancers. • Mutations in BALB mitochondrial DNA induce up-regulation of chemokine CCL20. • Increased growth and motility of mtBALB cells is associated with CCL20 levels. • mtDNA changes in BALB induce in vivo tumor growth through CCL20 up-regulation. • Mutations in mitochondrial DNA play important roles in keratinocyte neoplasia. - Abstract: mtDNA mutations are common in human cancers and are thought to contribute to the process of neoplasia. We examined the role of mtDNA mutations in skin cancer by generating fibroblast cybrids harboring a mutation in the gene encoding the mitochondrial tRNA for arginine. This somatic mutation (9821insA) was previously reported in UV-induced hyperkeratotic skin tumors in hairless mice and confers specific tumorigenic phenotypes to mutant cybrids. Microarray analysis revealed and RT-PCR along with Western blot analysis confirmed the up-regulation of CCL20 and its receptor CCR6 in mtBALB haplotype containing the mt-Tr 9821insA allele compared to wild type mtB6 haplotype. Based on reported role of CCL20 in cancer progression we examined whether the hyper-proliferation and enhanced motility of mtBALB haplotype would be associated with CCL20 levels. Treatment of both genotypes with recombinant CCL20 (rmCCL20) resulted in enhanced growth and motility of mtB6 cybrids. Furthermore, the acquired somatic alteration increased the in vivo tumor growth of mtBALB cybrids through the up-regulation of CCL20 since neutralizing antibody significantly decreased in vivo tumor growth of these cells; and tumors from anti-CCL20 treated mice injected with mtBALB cybrids showed significantly decreased CCL20 levels. When rmCCL20 or mtBALB cybrids were used as chemotactic stimuli, mtB6 cybrids showed increased motility while anti-CCL20 antibody decreased the migration and in vivo tumor growth of mtBALB cybrids. Moreover, the inhibitors of MAPK signaling and NF

  18. NMR investigation on isotope effect of glycinium phosphite H sub 3 NCH sub 2 COOH centre dot H sub 2 PO sub 3

    CERN Document Server

    Ishibashi, T

    2003-01-01

    The motions of the phosphite anions and glycinium cations in H sub 3 NCH sub 2 COOH centre dot H sub 2 PO sub 3 (GPI) and its deuterated analogue (DGPI) were investigated by sup 1 H, sup 1 sup 3 C and sup 3 sup 1 P spin-lattice relaxation times T sub 1. For both GPI and DGPI, T sub 1 's of the sup 1 H, sup 1 sup 3 C and sup 3 sup 1 P nuclei reflect the amino rotation, methylene libration and motion of the phosphite anions, respectively. Activation energies obtained from T sub 1 's of sup 1 H, sup 1 sup 3 C and sup 3 sup 1 P nuclei are 28.6(2), 26.0(4) and 26.2(4) kJ/mol for GPI and are 34.9(6), 27(1), 47(2) kJ/mol for DGPI, respectively. The deuterium substitution increases E sub a for the motion influenced by the hydrogen bonding. In all the observed motions, correlation times of DGPI are larger than those of GPI. (author)

  19. CCL2 binding is CCR2 independent in primary adult human astrocytes.

    Science.gov (United States)

    Fouillet, A; Mawson, J; Suliman, O; Sharrack, B; Romero, I A; Woodroofe, M N

    2012-02-09

    Chemokines are low relative molecular mass proteins, which have chemoattractant actions on many cell types. The chemokine, CCL2, has been shown to play a major role in the recruitment of monocytes in central nervous system (CNS) lesions in multiple sclerosis (MS). Since resident astrocytes constitute a major source of chemokine synthesis including CCL2, we were interested to assess the regulation of CCL2 by astrocytes. We showed that CCL2 bound to the cell surface of astrocytes and binding was not modulated by inflammatory conditions. However, CCR2 protein was not detected nor was activation of the classical CCR2 downstream signaling pathways. Recent studies have shown that non-signaling decoy chemokine receptors bind and modulate the expression of chemokines at site of inflammation. Here, we show that the D6 chemokine decoy receptor is constitutively expressed by primary human adult astrocytes at both mRNA and protein level. In addition, CCL3, which binds to D6, but not CCL19, which does not bind to D6, displaced CCL2 binding to astrocytes; indicating that CCL2 may bind to this cell type via the D6 receptor. Our results suggest that CCL2 binding to primary adult human astrocytes is CCR2-independent and is likely to be mediated via the D6 decoy chemokine receptor. Therefore we propose that astrocytes are implicated in both the establishment of chemokine gradients for the migration of leukocytes into and within the CNS and in the regulation of CCL2 levels at inflammatory sites in the CNS. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Stark-shift of impurity fundamental state in a lens shaped quantum dot

    Science.gov (United States)

    Aderras, L.; Bah, A.; Feddi, E.; Dujardin, F.; Duque, C. A.

    2017-05-01

    We calculate the Stark effect and the polarisability of shallow-donor impurity located in the centre of lens shaped quantum dot by a variational method and in the effective-mass approximation. Our theoretical model assumes an infinite confinement to describe the barriers at the dot boundaries and the electric field is considered to be applied in the z-direction. The systematic theoretical investigation contains results with the quantum dot size and the strength of the external field. Our calculations reveal that the interval wherein the polarisability varies depends strongly on the dot size.

  1. Haplotypes in CCR5-CCR2, CCL3 and CCL5 are associated with natural resistance to HIV-1 infection in a Colombian cohort.

    Science.gov (United States)

    Vega, Jorge A; Villegas-Ospina, Simón; Aguilar-Jiménez, Wbeimar; Rugeles, María T; Bedoya, Gabriel; Zapata, Wildeman

    2017-06-01

    Variants in genes encoding for HIV-1 co-receptors and their natural ligands have been individually associated to natural resistance to HIV-1 infection. However, the simultaneous presence of these variants has been poorly studied. To evaluate the association of single and multilocus haplotypes in genes coding for the viral co-receptors CCR5 and CCR2, and their ligands CCL3 and CCL5, with resistance or susceptibility to HIV-1 infection. Nine variants in CCR5-CCR2, two SNPs in CCL3 and two in CCL5 were genotyped by PCR-RFLP in 35 seropositive (cases) and 49 HIV-1-exposed seronegative Colombian individuals (controls). Haplotypes were inferred using the Arlequin software, and their frequency in individual or combined loci was compared between cases and controls by the chi-square test. A p' value ;0.05 after Bonferroni correction was considered significant. Homozygosis of the human haplogroup (HH) E was absent in controls and frequent in cases, showing a tendency to susceptibility. The haplotypes C-C and T-T in CCL3 were associated with susceptibility (p'=0.016) and resistance (p';0.0001) to HIV-1 infection, respectively. Finally, in multilocus analysis, the haplotype combinations formed by HHC in CCR5-CCR2, T-T in CCL3 and G-C in CCL5 were associated with resistance (p'=0.006). Our results suggest that specific combinations of variants in genes from the same signaling pathway can define an HIV-1 resistant phenotype. Despite our small sample size, our statistically significant associations suggest strong effects; however, these results should be further validated in larger cohorts.

  2. Structure-guided mutational analysis reveals the functional requirements for product specificity of DOT1 enzymes.

    Science.gov (United States)

    Dindar, Gülcin; Anger, Andreas M; Mehlhorn, Christine; Hake, Sandra B; Janzen, Christian J

    2014-11-12

    DOT1 enzymes are conserved methyltransferases that catalyse the methylation of lysine 79 on histone H3 (H3K79). Most eukaryotes contain one DOT1 enzyme, whereas African trypanosomes have two homologues, DOT1A and DOT1B, with different enzymatic activities. DOT1A mediates mono- and dimethylation of H3K76, the homologue of H3K79 in other organisms, whereas DOT1B additionally catalyses H3K76 trimethylation. However, it is unclear how these different enzymatic activities are achieved. Here we employ a trypanosomal nucleosome reconstitution system and structure-guided homology modelling to identify critical residues within and outside the catalytic centre that modulate product specificity. Exchange of these residues transfers the product specificity from one enzyme to the other, and reveals the existence of distinct regulatory domains adjacent to the catalytic centre. Our study provides the first evidence that a few crucial residues in DOT1 enzymes are sufficient to catalyse methyl-state-specific reactions. These results might also have far-reaching consequences for the functional understanding of homologous enzymes in higher eukaryotes.

  3. CCL2 responses to Mycobacterium tuberculosis are associated with disease severity in tuberculosis.

    Directory of Open Access Journals (Sweden)

    Zahra Hasan

    Full Text Available BACKGROUND: Leucocyte activating chemokines such as CCL2, CCL3, and CXCL8 together with proinflammatory IFNgamma, TNFalpha and downmodulatory IL10 play a central role in the restriction of M. tuberculosis infections, but is unclear whether these markers are indicative of tuberculosis disease severity. METHODOLOGY: We investigated live M. tuberculosis- and M. bovis BCG-induced peripheral blood mononuclear cell responses in patients with tuberculosis (TB and healthy endemic controls (ECs, n = 36. TB patients comprised pulmonary (PTB, n = 34 and extrapulmonary groups, subdivided into those with less severe localized extrapulmonary TB (L-ETB, n = 16 or severe disseminated ETB (D-ETB, n = 16. Secretion of CCL2, IFNgamma, IL10 and CCL3, and mRNA expression of CCL2, TNFalpha, CCL3 and CXCL8 were determined. RESULTS: M. tuberculosis- and BCG-induced CCL2 secretion was significantly increased in both PTB and D-ETB (p<0.05, p<0.01 as compared with L-ETB patients. CCL2 secretion in response to M. tuberculosis was significantly greater than to BCG in the PTB and D-ETB groups. M. tuberculosis-induced CCL2 mRNA transcription was greater in PTB than L-ETB (p = 0.023, while CCL2 was reduced in L-ETB as compared with D-ETB (p = 0.005 patients. M. tuberculosis-induced IFNgamma was greater in L-ETB than PTB (p = 0.04, while BCG-induced IFNgamma was greater in L-ETB as compared with D-ETB patients (p = 0.036. TNFalpha mRNA expression was raised in PTB as compared with L-ETB group in response to M. tuberculosis (p = 0.02 and BCG (p = 0.03. Mycobacterium-induced CCL3 and CXCL8 was comparable between TB groups. CONCLUSIONS: The increased CCL2 and TNFalpha in PTB patients may support effective leucocyte recruitment and M. tuberculosis localization. CCL2 alone is associated with severity of TB, possibly due to increased systemic inflammation found in severe disseminated TB or due to increased monocyte infiltration to lung parenchyma in pulmonary disease.

  4. Progress and Results from the 4DH Research Centre

    DEFF Research Database (Denmark)

    Werner, Sven; Lund, Henrik; Mathiesen, Brian Vad

    2014-01-01

    With lower and more flexible distribution temperatures, fourth generation district heating systems can utilize renewable energy sources, while meeting the requirements of low-energy buildings and energy conservation measures in the existing building stock. 4DH is an international strategic research...... centre located at Aalborg University, which develops 4th generation district heating technologies and systems (4GDH). This technology is fundamental to the implementation of the Danish objective of being fossil fuel-free by 2050 and the European 2020 goals. The research centre is working between 2012...... and 2017, with The Danish Council for Strategic Research as main financier and the participating 31 Danish and international companies and universities as cofinanciers. Thirteen PhD student projects constitute a vital part of the research centre. In 4GDH systems, synergies are created between three areas...

  5. Accuracy and differential bias in copy number measurement of CCL3L1 in association studies with three auto-immune disorders.

    Science.gov (United States)

    Carpenter, Danielle; Walker, Susan; Prescott, Natalie; Schalkwijk, Joost; Armour, John Al

    2011-08-18

    Copy number variation (CNV) contributes to the variation observed between individuals and can influence human disease progression, but the accurate measurement of individual copy numbers is technically challenging. In the work presented here we describe a modification to a previously described paralogue ratio test (PRT) method for genotyping the CCL3L1/CCL4L1 copy variable region, which we use to ascertain CCL3L1/CCL4L1 copy number in 1581 European samples. As the products of CCL3L1 and CCL4L1 potentially play a role in autoimmunity we performed case control association studies with Crohn's disease, rheumatoid arthritis and psoriasis clinical cohorts. We evaluate the PRT methodology used, paying particular attention to accuracy and precision, and highlight the problems of differential bias in copy number measurements. Our PRT methods for measuring copy number were of sufficient precision to detect very slight but systematic differential bias between results from case and control DNA samples in one study. We find no evidence for an association between CCL3L1 copy number and Crohn's disease, rheumatoid arthritis or psoriasis. Differential bias of this small magnitude, but applied systematically across large numbers of samples, would create a serious risk of false positive associations in copy number, if measured using methods of lower precision, or methods relying on single uncorroborated measurements. In this study the small differential bias detected by PRT in one sample set was resolved by a simple pre-treatment by restriction enzyme digestion.

  6. Accuracy and differential bias in copy number measurement of CCL3L1 in association studies with three auto-immune disorders

    Directory of Open Access Journals (Sweden)

    Carpenter Danielle

    2011-08-01

    Full Text Available Abstract Background Copy number variation (CNV contributes to the variation observed between individuals and can influence human disease progression, but the accurate measurement of individual copy numbers is technically challenging. In the work presented here we describe a modification to a previously described paralogue ratio test (PRT method for genotyping the CCL3L1/CCL4L1 copy variable region, which we use to ascertain CCL3L1/CCL4L1 copy number in 1581 European samples. As the products of CCL3L1 and CCL4L1 potentially play a role in autoimmunity we performed case control association studies with Crohn's disease, rheumatoid arthritis and psoriasis clinical cohorts. Results We evaluate the PRT methodology used, paying particular attention to accuracy and precision, and highlight the problems of differential bias in copy number measurements. Our PRT methods for measuring copy number were of sufficient precision to detect very slight but systematic differential bias between results from case and control DNA samples in one study. We find no evidence for an association between CCL3L1 copy number and Crohn's disease, rheumatoid arthritis or psoriasis. Conclusions Differential bias of this small magnitude, but applied systematically across large numbers of samples, would create a serious risk of false positive associations in copy number, if measured using methods of lower precision, or methods relying on single uncorroborated measurements. In this study the small differential bias detected by PRT in one sample set was resolved by a simple pre-treatment by restriction enzyme digestion.

  7. Hepatoprotective activity of petroleum ether, diethyl ether, and methanol extract of Scoparia dulcis L. against CCl4-induced acute liver injury in mice.

    Science.gov (United States)

    Praveen, T K; Dharmaraj, S; Bajaj, Jitendra; Dhanabal, S P; Manimaran, S; Nanjan, M J; Razdan, Rema

    2009-06-01

    The present study was aimed at assessing the hepatoprotective activity of 1:1:1 petroleum ether, diethyl ether, and methanol (PDM) extract of Scoparia dulcis L. against carbon tetrachloride-induced acute liver injury in mice. The PDM extract (50, 200, and 800 mg/kg, p.o.) and standard, silymarin (100 mg/kg, p.o) were tested for their antihepatotoxic activity against CCl4-induced acute liver injury in mice. The hepatoprotective activity was evaluated by measuring aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and total proteins in serum, glycogen, lipid peroxides, superoxide dismutase, and glutathione reductase levels in liver homogenate and by histopathological analysis of the liver tissue. In addition, the extract was also evaluated for its in vitro antioxidant activity using 1, 1-Diphenyl-2-picrylhydrazyl scavenging assay. The extract at the dose of 800 mg/kg, p.o., significantly prevented CCl4-induced changes in the serum and liver biochemistry (P Scoparia dulcis L. possesses potential hepatoprotective activity, which may be attributed to its free radical scavenging potential, due to the terpenoid constituents.

  8. Autocrine CCL19 blocks dendritic cell migration toward weak gradients of CCL21

    DEFF Research Database (Denmark)

    Hansen, Morten; Met, Özcan; Larsen, Niels Bent

    2016-01-01

    Background aims. Maturation of dendritic cells (DCs) induces their homing from peripheral to lymphatic tissues guided by CCL21. However, in vitro matured human monocyte-derived DC cancer vaccines injected intradermally migrate poorly to lymph nodes (LNs). In vitro maturation protocols generate DCs...

  9. Neuronal CCL2 is upregulated during hepatic encephalopathy and contributes to microglia activation and neurological decline.

    Science.gov (United States)

    McMillin, Matthew; Frampton, Gabriel; Thompson, Michelle; Galindo, Cheryl; Standeford, Holly; Whittington, Eric; Alpini, Gianfranco; DeMorrow, Sharon

    2014-07-10

    Acute liver failure leads to systemic complications with one of the most dangerous being a decline in neurological function, termed hepatic encephalopathy. Neurological dysfunction is exacerbated by an increase of toxic metabolites in the brain that lead to neuroinflammation. Following various liver diseases, hepatic and circulating chemokines, such as chemokine ligand 2 (CCL2), are elevated, though their effects on the brain following acute liver injury and subsequent hepatic encephalopathy are unknown. CCL2 is known to activate microglia in other neuropathies, leading to a proinflammatory response. However, the effects of CCL2 on microglia activation and the pathogenesis of hepatic encephalopathy following acute liver injury remain to be determined. Hepatic encephalopathy was induced in mice via injection of azoxymethane (AOM) in the presence or absence of INCB 3284 dimesylate (INCB), a chemokine receptor 2 inhibitor, or C 021 dihydrochloride (C021), a chemokine receptor 4 inhibitor. Mice were monitored for neurological decline and time to coma (loss of all reflexes) was recorded. Tissue was collected at coma and used for real-time PCR, immunoblots, ELISA, or immunostaining analyses to assess the activation of microglia and consequences on pro-inflammatory cytokine expression. Following AOM administration, microglia activation was significantly increased in AOM-treated mice compared to controls. Concentrations of CCL2 in the liver, serum, and cortex were significantly elevated in AOM-treated mice compared to controls. Systemic administration of INCB or C021 reduced liver damage as assessed by serum liver enzyme biochemistry. Administration of INCB or C021 significantly improved the neurological outcomes of AOM-treated mice, reduced microglia activation, reduced phosphorylation of ERK1/2, and alleviated AOM-induced cytokine upregulation. These findings suggest that CCL2 is elevated systemically following acute liver injury and that CCL2 is involved in both the

  10. A New Oleanolic Acid Derivative against CCl4-Induced Hepatic Fibrosis in Rats

    Directory of Open Access Journals (Sweden)

    Hongjun Xiang

    2017-03-01

    Full Text Available A novel hepatoprotective oleanolic acid derivative, 3-oxours-oleana-9(11, 12-dien-28-oic acid (Oxy-Di-OA, has been reported. In previous studies, we found that Oxy-Di-OA presented the anti-HBV (Hepatitis B Virus activity (IC50 = 3.13 µg/mL. Remarkably, it is superior to lamivudine in the inhibition of the rebound of the viral replication rate. Furthermore, Oxy-Di-OA showed good performance of anti-HBV activity in vivo. Some studies showed that liver fibrosis may affiliate with HBV gene mutations. In addition, the anti-hepatic fibrosis activity of Oxy-Di-OA has not been studied. Therefore, we evaluated the protective effect of Oxy-Di-OA against carbon tetrachloride (CCl4-induced liver injury in rats. Daily intraperitoneally administration of Oxy-Di-OA prevented the development of CCl4-induced liver fibrosis, which was evidenced by histological study and immunohistochemical analysis. The entire experimental protocol lasted nine weeks. Oxy-Di-OA significantly suppressed the increases of plasma aspartate aminotransferase (AST and alanine aminotransferase (ALT levels (p < 0.05. Furthermore, Oxy-Di-OA could prevent expression of transforming growth factor β1 (TGF-β1. It is worth noting that the high-dose group Oxy-Di-OA is superior to bifendate in elevating hepatic function. Compared to the model group, Oxy-Di-OA in the high-dose group and low-dose group can significantly reduce the liver and spleen indices (p < 0.05. The acute toxicity test showed that LD50 and a 95% confidence interval (CIs value of Oxy-Di-OA were 714.83 mg/kg and 639.73–798.73 mg/kg via intraperitoneal injection in mice, respectively. The LD50 value of Oxy-Di-OA exceeded 2000 mg/kg via gavage in mice. In addition, a simple and rapid high performance liquid chromatography-ultraviolet (HPLC-UV method was developed and validated to study the pharmacokinetic characteristics of the compound. After single-dose oral administration, time to reach peak concentration of Oxy-Di-OA (Cmax

  11. An eco-friendly molecularly imprinted fluorescence composite material based on carbon dots for fluorescent detection of 4-nitrophenol

    International Nuclear Information System (INIS)

    Hao, Tongfan; Wei, Xiao; Nie, Yijing; Zhou, Zhiping; Xu, Yeqing; Yan, Yongsheng

    2016-01-01

    We on report an eco-friendly molecularly imprinted material based on carbon dots (C-dots) via a facile and efficient sol–gel polymerization for selective fluorescence detection of 4-nitrophenol (4-NP). The amino-modified C-dots were firstly synthesized by a hydrothermal process using citric acid as the carbon source and poly(ethyleneimine) as the surface modifier, and then after a sol–gel molecular imprinting process, the molecularly imprinted fluorescence material was obtained. The material (MIP-C-dots) showed strong fluorescence from C-dots and high selectivity due to the presence of a molecular imprint. After the detection conditions were optimized, the relative fluorescence intensity (F_0/F) of MIP-C-dots presented a good linearity with 4-NP concentrations in the linear range of 0.2 − 50 μmol L"-"1 with a detection limit (3σ/k) of 0.06 μmol L"-"1. In addition, the correlation coefficient was 0.9978 and the imprinting factor was 2.76. The method was applicable to the determination of trace 4-NP in Yangtze River water samples and good recoveries from 92.6–107.3 % were obtained. The present study provides a general strategy to fabricate materials based on C-dots with good fluorescence property for selective fluorescence detection of organic pollutants. (author)

  12. Engineering colloidal quantum dot solids within and beyond the mobility-invariant regime

    KAUST Repository

    Zhitomirsky, David

    2014-05-06

    © 2014 Macmillan Publishers Limited. Colloidal quantum dots are attractive materials for efficient, low-cost and facile implementation of solution-processed optoelectronic devices. Despite impressive mobilities (1-30 cm2V-1 s-1) reported for new classes of quantum dot solids, it is-surprisingly-the much lower-mobility (10-3-10-2 cm2V-1 s-1) solids that have produced the best photovoltaic performance. Here we show that it is not mobility, but instead the average spacing among recombination centres that governs the diffusion length of charges in today\\'s quantum dot solids. In this regime, colloidal quantum dot films do not benefit from further improvements in charge carrier mobility. We develop a device model that accurately predicts the thickness dependence and diffusion length dependence of devices. Direct diffusion length measurements suggest the solid-state ligand exchange procedure as a potential origin of the detrimental recombination centres. We then present a novel avenue for in-solution passivation with tightly bound chlorothiols that retain passivation from solution to film, achieving an 8.5% power conversion efficiency.

  13. Protective Effect of Zingiber Officinale against CCl4-Induced Liver Fibrosis Is Mediated through Downregulating the TGF-β1/Smad3 and NF-ĸB/IĸB Pathways.

    Science.gov (United States)

    Hasan, Iman H; El-Desouky, M A; Hozayen, Walaa G; Abd el Aziz, Ghada M

    2016-01-01

    No ideal hepatoprotective agents are available in modern medicine to effectively prevent liver disorders. In this study, we aimed at evaluating the potential of Zingiber officinale in the regression of liver fibrosis and its underlining mechanism of action. To induce liver fibrosis, male Wistar rats received CCl4 (2 ml/kg/2 times/week; i.p.), with and without 300 or 600 mg/kg Z. officinale extract daily through oral gavage. To assess the protective effect of Z. officinale, liver function parameters, histopathology, inflammatory markers and gene expression of transforming growth factor-beta 1 (TGF-β1)/Smad3 and nuclear factor-kappa B (NF-ĸB)/IĸB pathways were analyzed. Results demonstrate that Z. officinale extract markedly prevented liver injury as evident by the decreased liver marker enzymes. Concurrent administration of Z. officinale significantly protected against the CCl4-induced inflammation as showed by the decreased pro-inflammatory cytokine levels as well as the downregulation of the NF-ĸB)/IĸB and TGF-β1/Smad3 pathways in CCl4-administered rats. In conclusion, our study provides evidence that the protective effect of Z. officinale against rat liver fibrosis could be explained through its ability to modulate the TGF-β1/Smad3 and NF-ĸB)/IĸB signaling pathways. © 2015 S. Karger AG, Basel.

  14. Highly fluorescent carbon dots as nanoprobes for sensitive and selective determination of 4-nitrophenol in surface waters

    International Nuclear Information System (INIS)

    Ahmed, Gaber Hashem Gaber; Laíño, Rosana Badía; Calzón, Josefa Angela García; García, Marta Elena Díaz

    2015-01-01

    We report on the synthesis of carbon dots (C-dots) by thermal carbonization of a mixture of ethyleneglycol bis-(2-aminoethyl ether)-N,N,N’,N’-tetraacetic acid (EGTA) and tris(hydroxymethyl)aminomethane (Tris). The resulting C-dots were characterized by X-ray diffraction, proton and carbon nuclear magnetic resonance, FTIR and fluorescence spectroscopy, and high-resolution TEM. The data reveal that the C-dots are mainly capped with hydroxy and carbonyl groups and are highly fluorescent with an emission peak that shifts from 427 to 438 nm if the excitation wavelength is increased from 310 to 360–370 nm. Fluorescence is quenched by 4-nitrophenol (4-NP), and this effect was exploited to design a simple and rapid protocol for the determination of 4-NP. The detection limit is 28 nM and the linear range extends from 0.1 to 50 μM. The method was successfully applied to the determination of 4-NP in spiked river and sea waters. (author)

  15. Serum PARC/CCL-18 concentrations and health outcomes in chronic obstructive pulmonary disease.

    Science.gov (United States)

    Sin, Don D; Miller, Bruce E; Duvoix, Annelyse; Man, S F Paul; Zhang, Xuekui; Silverman, Edwin K; Connett, John E; Anthonisen, Nicholas A; Wise, Robert A; Tashkin, Donald; Celli, Bartolome R; Edwards, Lisa D; Locantore, Nicholas; Macnee, William; Tal-Singer, Ruth; Lomas, David A

    2011-05-01

    There are no accepted blood-based biomarkers in chronic obstructive pulmonary disease (COPD). Pulmonary and activation-regulated chemokine (PARC/CCL-18) is a lung-predominant inflammatory protein that is found in serum. To determine whether PARC/CCL-18 levels are elevated and modifiable in COPD and to determine their relationship to clinical end points of hospitalization and mortality. PARC/CCL-18 was measured in serum samples from individuals who participated in the ECLIPSE (Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints) and LHS (Lung Health Study) studies and a prednisolone intervention study. Serum PARC/CCL-18 levels were higher in subjects with COPD than in smokers or lifetime nonsmokers without COPD (105 vs. 81 vs. 80 ng/ml, respectively; P < 0.0001). Elevated PARC/CCL-18 levels were associated with increased risk of cardiovascular hospitalization or mortality in the LHS cohort and with total mortality in the ECLIPSE cohort. Serum PARC/CCL-18 levels are elevated in COPD and track clinical outcomes. PARC/CCL-18, a lung-predominant chemokine, could be a useful blood biomarker in COPD.

  16. Serum concentrations of chemokines (CCL-5 and CXCL-12), chemokine receptors (CCR-5 and CXCR-4), and IL-6 in patients with posttraumatic stress disorder and avoidant personality disorder.

    Science.gov (United States)

    Ogłodek, Ewa A; Szota, Anna M; Moś, Danuta M; Araszkiewicz, Aleksander; Szromek, Adam R

    2015-12-01

    Posttraumatic stress disorder (PTSD) can be perceived as a psychoneuroimmunological disorder in which cytokines affecting the neurochemical and neuroendocrine functions of the body play an important role. Among cytokines, chemokines participating in activation of the inflammatory response are considered to be crucial. 220 men and women were enrolled in the study. 180 of them constituted the study group. The studied groups consisted of: 60 patients with a diagnosed avoidant personality disorders (APD), 60 patients with a diagnosed APD and with PTSD and of 60 patients with PTSD but without a APD. There were 30 women and 30 men in each group of 60 subjects. The control group consisted of 40 healthy individuals. The plasma levels of chemokines and their receptors (CCL-5, CXCR-5, CXCL-12 and CXCR-4), as well as IL-6, were assessed by ELISA. There was an increase in the CXCL-12 and CCL-5 levels in women and men with the PTSD versus the control group. Also, increased levels of IL-6 and the receptors CXCR-4, CCR-5 were observed in women and men with PTSD. The levels of CXCL-12 and CCL-5 chemokines, as well as CCR-5 and CXCR4 receptors were higher in women than in men. The results of this study indicate a need for assessment of the CCL-5 and CXCL-12 chemokine levels, as they are likely markers of PTSD. Measurement of the concentrations of chemokines, chemokine receptors and IL-6 in women and men with PTSD along with concomittant APD may be useful for early detection of mental disorders. Copyright © 2015 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  17. A highly efficient single-photon source based on a quantum dot in a photonic nanowire

    DEFF Research Database (Denmark)

    Claudon, Julien; Bleuse, Joel; Malik, Nitin Singh

    2010-01-01

    4 or a semiconductor quantum dot5–7. Achieving a high extraction efficiency has long been recognized as a major issue, and both classical solutions8 and cavity quantum electrodynamics effects have been applied1,9–12. We adopt a different approach, based on an InAs quantum dot embedded in a GaAs photonic nanowire......The development of efficient solid-state sources of single photons is a major challenge in the context of quantum communication,optical quantum information processing and metrology1. Such a source must enable the implementation of a stable, single-photon emitter, like a colour centre in diamond2...

  18. Targeting CCl4 -induced liver fibrosis by RNA interference-mediated inhibition of cyclin E1 in mice.

    Science.gov (United States)

    Bangen, Jörg-Martin; Hammerich, Linda; Sonntag, Roland; Baues, Maike; Haas, Ute; Lambertz, Daniela; Longerich, Thomas; Lammers, Twan; Tacke, Frank; Trautwein, Christian; Liedtke, Christian

    2017-10-01

    Initiation and progression of liver fibrosis requires proliferation and activation of resting hepatic stellate cells (HSCs). Cyclin E1 (CcnE1) is the regulatory subunit of the cyclin-dependent kinase 2 (Cdk2) and controls cell cycle re-entry. We have recently shown that genetic inactivation of CcnE1 prevents activation, proliferation, and survival of HSCs and protects from liver fibrogenesis. The aim of the present study was to translate these findings into preclinical applications using an RNA interference (RNAi)-based approach. CcnE1-siRNA (small interfering RNA) efficiently inhibited CcnE1 gene expression in murine and human HSC cell lines and in primary HSCs, resulting in diminished proliferation and increased cell death. In C57BL/6 wild-type (WT) mice, delivery of stabilized siRNA using a liposome-based carrier targeted approximately 95% of HSCs, 70% of hepatocytes, and 40% of CD45 + cells after single injection. Acute CCl 4 -mediated liver injury in WT mice induced endogenous CcnE1 expression and proliferation of surviving hepatocytes and nonparenchymal cells, including CD45 + leukocytes. Pretreatment with CcnE1-siRNA reverted CcnE1 induction to baseline levels of healthy mice, which was associated with reduced liver injury, diminished proliferation of hepatocytes and leukocytes, and attenuated overall inflammatory response. For induction of liver fibrosis, WT mice were challenged with CCl 4 for 4-6 weeks. Co-treatment with CcnE1-siRNA once a week was sufficient to continuously block CcnE1 expression and cell-cycle activity of hepatocytes and nonparenchymal cells, resulting in significantly ameliorated liver fibrosis and inflammation. Importantly, CcnE1-siRNA also prevented progression of liver fibrosis if applied after onset of chronic liver injury. Therapeutic targeting of CcnE1 in vivo using RNAi is feasible and has high antifibrotic activity. (Hepatology 2017;66:1242-1257). © 2017 by the American Association for the Study of Liver Diseases.

  19. Distinct Upstream Role of Type I IFN Signaling in Hematopoietic Stem Cell-Derived and Epithelial Resident Cells for Concerted Recruitment of Ly-6Chi Monocytes and NK Cells via CCL2-CCL3 Cascade.

    Directory of Open Access Journals (Sweden)

    Erdenebileg Uyangaa

    Full Text Available Type I interferon (IFN-I-dependent orchestrated mobilization of innate cells in inflamed tissues is believed to play a critical role in controlling replication and CNS-invasion of herpes simplex virus (HSV. However, the crucial regulators and cell populations that are affected by IFN-I to establish the early environment of innate cells in HSV-infected mucosal tissues are largely unknown. Here, we found that IFN-I signaling promoted the differentiation of CCL2-producing Ly-6Chi monocytes and IFN-γ/granzyme B-producing NK cells, whereas deficiency of IFN-I signaling induced Ly-6Clo monocytes producing CXCL1 and CXCL2. More interestingly, recruitment of Ly-6Chi monocytes preceded that of NK cells with the levels peaked at 24 h post-infection in IFN-I-dependent manner, which was kinetically associated with the CCL2-CCL3 cascade response. Early Ly-6Chi monocyte recruitment was governed by CCL2 produced from hematopoietic stem cell (HSC-derived leukocytes, whereas NK cell recruitment predominantly depended on CC chemokines produced by resident epithelial cells. Also, IFN-I signaling in HSC-derived leukocytes appeared to suppress Ly-6Ghi neutrophil recruitment to ameliorate immunopathology. Finally, tissue resident CD11bhiF4/80hi macrophages and CD11chiEpCAM+ dendritic cells appeared to produce initial CCL2 for migration-based self-amplification of early infiltrated Ly-6Chi monocytes upon stimulation by IFN-I produced from infected epithelial cells. Ultimately, these results decipher a detailed IFN-I-dependent pathway that establishes orchestrated mobilization of Ly-6Chi monocytes and NK cells through CCL2-CCL3 cascade response of HSC-derived leukocytes and epithelium-resident cells. Therefore, this cascade response of resident-to-hematopoietic-to-resident cells that drives cytokine-to-chemokine-to-cytokine production to recruit orchestrated innate cells is critical for attenuation of HSV replication in inflamed tissues.

  20. On the diameter of dot-critical graphs

    Directory of Open Access Journals (Sweden)

    Doost Ali Mojdeh

    2009-01-01

    Full Text Available A graph G is \\(k\\-dot-critical (totaly \\(k\\-dot-critical if \\(G\\ is dot-critical (totaly dot-critical and the domination number is \\(k\\. In the paper [T. Burtona, D. P. Sumner, Domination dot-critical graphs, Discrete Math, 306 (2006, 11-18] the following question is posed: What are the best bounds for the diameter of a \\(k\\-dot-critical graph and a totally \\(k\\-dot-critical graph \\(G\\ with no critical vertices for \\(k \\geq 4\\? We find the best bound for the diameter of a \\(k\\-dot-critical graph, where \\(k \\in\\{4,5,6\\}\\ and we give a family of \\(k\\-dot-critical graphs (with no critical vertices with sharp diameter \\(2k-3\\ for even \\(k \\geq 4\\.

  1. Ccl22/MDC, is a prostaglandin dependent pyrogen, acting in the anterior hypothalamus to induce hyperthermia via activation of brown adipose tissue.

    Science.gov (United States)

    Osborn, Olivia; Sanchez-Alavez, Manuel; Dubins, Jeffrey S; Gonzalez, Alejandro Sanchez; Morrison, Brad; Hadcock, John R; Bartfai, Tamas

    2011-03-01

    CC Chemokine ligand 22 (Ccl22) is a selective, high affinity ligand at the CC chemokine receptor 4 (Ccr4). We have identified cDNAs encoding both ligand and receptor of the Ccl22-Ccr4 pair in cDNA libraries of the anterior hypothalamus/pre-optic area (AH/POA) by PCR. The AH/POA is the key brain region where endogenous pyrogens have been shown to act on warm sensitive neurons to affect thermogenesis in brown adipose tissue (BAT) and other thermogenically responsive tissues. We show that functional Ccr4 receptors are present in the AH/POA neurons as injection of Ccl22 into the POA but not to other hypothalamic nuclei induces an increase in core body temperature as measured by radiotelemetry. Indomethacin (5 mg/kg s.c) pre-treatment markedly reduced the hyperthermia evoked by POA injection of Ccl22 (10 ng/0.5 ul) and thus suggests that this hyperthermia is mediated through cyclooxygenase activation and thus likely through the formation and action of the pyrogen prostaglandin E2. The temperature elevation involves a decrease in the respiratory exchange ratio and increased activation of the brown adipose tissue as demonstrated by ¹⁸F-FDG-PET imaging. We describe a novel role to the ligand Ccl22 and its receptor Ccr4 in the anterior hypothalamus in temperature regulation that depends on the synthesis of the endogenous pyrogen, prostaglandin E2. Copyright © 2010 Elsevier Ltd. All rights reserved.

  2. Quantum Dots

    Science.gov (United States)

    Tartakovskii, Alexander

    2012-07-01

    Part I. Nanostructure Design and Structural Properties of Epitaxially Grown Quantum Dots and Nanowires: 1. Growth of III/V semiconductor quantum dots C. Schneider, S. Hofling and A. Forchel; 2. Single semiconductor quantum dots in nanowires: growth, optics, and devices M. E. Reimer, N. Akopian, M. Barkelid, G. Bulgarini, R. Heeres, M. Hocevar, B. J. Witek, E. Bakkers and V. Zwiller; 3. Atomic scale analysis of self-assembled quantum dots by cross-sectional scanning tunneling microscopy and atom probe tomography J. G. Keizer and P. M. Koenraad; Part II. Manipulation of Individual Quantum States in Quantum Dots Using Optical Techniques: 4. Studies of the hole spin in self-assembled quantum dots using optical techniques B. D. Gerardot and R. J. Warburton; 5. Resonance fluorescence from a single quantum dot A. N. Vamivakas, C. Matthiesen, Y. Zhao, C.-Y. Lu and M. Atature; 6. Coherent control of quantum dot excitons using ultra-fast optical techniques A. J. Ramsay and A. M. Fox; 7. Optical probing of holes in quantum dot molecules: structure, symmetry, and spin M. F. Doty and J. I. Climente; Part III. Optical Properties of Quantum Dots in Photonic Cavities and Plasmon-Coupled Dots: 8. Deterministic light-matter coupling using single quantum dots P. Senellart; 9. Quantum dots in photonic crystal cavities A. Faraon, D. Englund, I. Fushman, A. Majumdar and J. Vukovic; 10. Photon statistics in quantum dot micropillar emission M. Asmann and M. Bayer; 11. Nanoplasmonics with colloidal quantum dots V. Temnov and U. Woggon; Part IV. Quantum Dot Nano-Laboratory: Magnetic Ions and Nuclear Spins in a Dot: 12. Dynamics and optical control of an individual Mn spin in a quantum dot L. Besombes, C. Le Gall, H. Boukari and H. Mariette; 13. Optical spectroscopy of InAs/GaAs quantum dots doped with a single Mn atom O. Krebs and A. Lemaitre; 14. Nuclear spin effects in quantum dot optics B. Urbaszek, B. Eble, T. Amand and X. Marie; Part V. Electron Transport in Quantum Dots Fabricated by

  3. TWEAK activates the non-canonical NFkappaB pathway in murine renal tubular cells: modulation of CCL21.

    Directory of Open Access Journals (Sweden)

    Ana B Sanz

    2010-01-01

    Full Text Available TWEAK is a member of the TNF superfamily of cytokines that contribute to kidney tubulointerstitial injury. It has previously been reported that TWEAK induces transient nuclear translocation of RelA and expression of RelA-dependent cytokines in renal tubular cells. Additionally, TWEAK induced long-lasting NFkappaB activation suggestive of engagement of the non-canonical NFkappaB pathway. We now explore TWEAK-induced activation of NFkappaB2 and RelB, as well as expression of CCL21, a T-cell chemotactic factor, in cultured murine tubular epithelial cells and in healthy kidneys in vivo. In cultured tubular cells, TWEAK and TNFalpha activated different DNA-binding NFkappaB complexes. TWEAK-induced sustained NFkappaB activation was associated with NFkappaB2 p100 processing to p52 via proteasome and nuclear translocation and DNA-binding of p52 and RelB. TWEAK, but not TNFalpha used as control, induced a delayed increase in CCL21a mRNA (3.5+/-1.22-fold over control and CCL21 protein (2.5+/-0.8-fold over control, which was prevented by inhibition of the proteasome, or siRNA targeting of NIK or RelB, but not by RelA inhibition with parthenolide. A second NFkappaB2-dependent chemokine, CCL19, was upregulates by TWEAK, but not by TNFalpha. However, both cytokines promoted chemokine RANTES expression (3-fold mRNA at 24 h. In vivo, TWEAK induced nuclear NFkappaB2 and RelB translocation and CCL21a mRNA (1.5+/-0.3-fold over control and CCL21 protein (1.6+/-0.5-fold over control expression in normal kidney. Increased tubular nuclear RelB and tubular CCL21 expression in acute kidney injury were decreased by neutralization (2+/-0.9 vs 1.3+/-0.6-fold over healthy control or deficiency of TWEAK (2+/-0.9 vs 0.8+/-0.6-fold over healthy control. Moreover, anti-TWEAK treatment prevented the recruitment of T cells to the kidney in this model (4.1+/-1.4 vs 1.8+/-1-fold over healthy control. Our results thus identify TWEAK as a regulator of non-canonical NFkappa

  4. Complex dynamics in planar two-electron quantum dots

    International Nuclear Information System (INIS)

    Schroeter, Sebastian Josef Arthur

    2013-01-01

    Quantum dots play an important role in a wide range of recent experimental and technological developments. In particular they are promising candidates for realisations of quantum bits and further applications in quantum information theory. The harmonically confined Hooke's atom model is experimentally verified and separates in centre-of-mass and relative coordinates. Findings that are contradictory to this separability call for an extension of the model, in particular changing the confinement potential. In order to study effects of an anharmonic confinement potential on spectral properties of planar two-electron quantum dots a sophisticated numerical approach is developed. Comparison between the Helium atom, Hooke's atom and an anharmonic potential model are undertaken in order to improve the description of quantum dots. Classical and quantum features of complexity and chaos are investigated and used to characterise the dynamics of the system to be mixed regular-chaotic. Influence of decoherence can be described by quantum fidelity, which measures the effect of a perturbation on the time evolution. The quantum fidelity of eigenstates of the system depends strongly on the properties of the perturbation. Several methods for solving the time-dependent Schrödinger equation are implemented and a high level of accuracy for long time evolutions is achieved. The concept of offset entanglement, the entanglement of harmonic models in the noninteracting limit, is introduced. This concept explains different questions raised in the literature for harmonic quantum dot models, recently. It shows that only in the groundstate the electrons are not entangled in the fermionic sense. The applicability, validity, and origin of Hund's first rule in general quantum dot models is further addressed. In fact Hund's first rule is only applicable, and in this case also valid, for one pair of singlet and triplet states in Hooke's atom. For more realistic models of two-electron quantum dots an

  5. Serum PARC/CCL-18 Concentrations and Health Outcomes in Chronic Obstructive Pulmonary Disease

    Science.gov (United States)

    Sin, Don D.; Miller, Bruce E.; Duvoix, Annelyse; Man, S. F. Paul; Zhang, Xuekui; Silverman, Edwin K.; Connett, John E.; Anthonisen, Nicholas A.; Wise, Robert A.; Tashkin, Donald; Celli, Bartolome R.; Edwards, Lisa D.; Locantore, Nicholas; MacNee, William; Tal-Singer, Ruth; Lomas, David A.

    2011-01-01

    Rationale: There are no accepted blood-based biomarkers in chronic obstructive pulmonary disease (COPD). Pulmonary and activation-regulated chemokine (PARC/CCL-18) is a lung-predominant inflammatory protein that is found in serum. Objectives: To determine whether PARC/CCL-18 levels are elevated and modifiable in COPD and to determine their relationship to clinical end points of hospitalization and mortality. Methods: PARC/CCL-18 was measured in serum samples from individuals who participated in the ECLIPSE (Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints) and LHS (Lung Health Study) studies and a prednisolone intervention study. Measurements and Main Results: Serum PARC/CCL-18 levels were higher in subjects with COPD than in smokers or lifetime nonsmokers without COPD (105 vs. 81 vs. 80 ng/ml, respectively; P LHS cohort and with total mortality in the ECLIPSE cohort. Conclusions: Serum PARC/CCL-18 levels are elevated in COPD and track clinical outcomes. PARC/CCL-18, a lung-predominant chemokine, could be a useful blood biomarker in COPD. Clinical trial registered with www.clinicaltrials.gov (NCT 00292552). PMID:21216880

  6. Complete quantum control of exciton qubits bound to isoelectronic centres.

    Science.gov (United States)

    Éthier-Majcher, G; St-Jean, P; Boso, G; Tosi, A; Klem, J F; Francoeur, S

    2014-05-30

    In recent years, impressive demonstrations related to quantum information processing have been realized. The scalability of quantum interactions between arbitrary qubits within an array remains however a significant hurdle to the practical realization of a quantum computer. Among the proposed ideas to achieve fully scalable quantum processing, the use of photons is appealing because they can mediate long-range quantum interactions and could serve as buses to build quantum networks. Quantum dots or nitrogen-vacancy centres in diamond can be coupled to light, but the former system lacks optical homogeneity while the latter suffers from a low dipole moment, rendering their large-scale interconnection challenging. Here, through the complete quantum control of exciton qubits, we demonstrate that nitrogen isoelectronic centres in GaAs combine both the uniformity and predictability of atomic defects and the dipole moment of semiconductor quantum dots. This establishes isoelectronic centres as a promising platform for quantum information processing.

  7. Vectorization of DOT3.5 code

    International Nuclear Information System (INIS)

    Nonomiya, Iwao; Ishiguro, Misako; Tsutsui, Tsuneo

    1990-07-01

    In this report, we describe the vectorization of two-dimensional Sn-method radiation transport code DOT3.5. Vectorized codes are not only the NEA original version developed at ORNL but also the versions improved by JAERI: DOT3.5 FNS version for fusion neutronics analyses, DOT3.5 FER version for fusion reactor design, and ESPRIT module of RADHEAT-V4 code system for radiation shielding and radiation transport analyses. In DOT3.5, input/output processing time amounts to a great part of the elapsed time when a large number of energy groups and/or a large number of spatial mesh points are used in the calculated problem. Therefore, an improvement has been made for the speedup of input/output processing in the DOT3.5 FNS version, and DOT-DD (Double Differential cross section) code. The total speedup ratio of vectorized version to the original scalar one is 1.7∼1.9 for DOT3.5 NEA version, 2.2∼2.3 fro DOT3.5 FNS version, 1.7 for DOT3.5 FER version, and 3.1∼4.4 for RADHEAT-V4, respectively. The elapsed times for improved DOT3.5 FNS version and DOT-DD are reduced to 50∼65% that of the original version by the input/output speedup. In this report, we describe summary of codes, the techniques used for the vectorization and input/output speedup, verification of computed results, and speedup effect. (author)

  8. Red light emitting solid state hybrid quantum dot-near-UV GaN LED devices

    International Nuclear Information System (INIS)

    Song, Hongjoo; Lee, Seonghoon

    2007-01-01

    We produced core-shell (CdSe)ZnSe quantum dots by direct colloidal chemical synthesis and the surface-passivation method-an overcoating of the core CdSe with a larger-bandgap material ZnSe. The (CdSe)ZnSe quantum dots(QDs) play the role of a colour conversion centre. We call these quantum dots nanophosphors. We fabricated red light emitting hybrid devices of (CdSe)ZnSe QDs and a near-UV GaN LED by combining red light emitting (CdSe)ZnSe quantum dots (as a colour conversion centre) with a near-UV(NUV) GaN LED chip (as an excitation source). A few good red phosphors have been known for UV excitation wavelengths, and red phosphors for UV excitation have been sought for a long time. Here we tested the possibility of using (CdSe)ZnSe QDs as red nanophosphors for UV excitation. The fabricated red light emitting hybrid device of (CdSe)ZnSe and a NUV GaN LED chip showed a good luminance. We demonstrated that the (CdSe)ZnSe quantum dots were promising red nanophosphors for NUV excitation and that a red LED made of QDs and a NUV excitation source was a highly efficient hybrid device

  9. CCL8 BASED IMMUNOLOGICAL MONITORING

    DEFF Research Database (Denmark)

    2008-01-01

    The present invention relates to an immunological method and, more particularly, a method for measuring cell-mediated immune reactivity (CMI) in mammals based on the production of CCL8.The invention further discloses an assay and a kit for measuring CMI to an antigen using whole blood or other...

  10. Serum CCL-18 level is a risk factor for COPD exacerbations requiring hospitalization

    Science.gov (United States)

    Dilektasli, Asli Gorek; Demirdogen Cetinoglu, Ezgi; Uzaslan, Esra; Budak, Ferah; Coskun, Funda; Ursavas, Ahmet; Ercan, Ilker; Ege, Ercument

    2017-01-01

    Introduction Chemokine (C-C motif) ligand 18 (CCL-18) has been shown to be elevated in chronic obstructive pulmonary disease (COPD) patients. This study primarily aimed to evaluate whether the serum CCL-18 level differentiates the frequent exacerbator COPD phenotype from infrequent exacerbators. The secondary aim was to investigate whether serum CCL-18 level is a risk factor for exacerbations requiring hospitalization. Materials and methods Clinically stable COPD patients and participants with smoking history but normal spirometry (NSp) were recruited for the study. Modified Medical Research Council Dyspnea Scale, COPD Assessment Test, spirometry, and 6-min walking test were performed. Serum CCL-18 levels were measured with a commercial ELISA Kit. Results Sixty COPD patients and 20 NSp patients were recruited. Serum CCL-18 levels were higher in COPD patients than those in NSp patients (169 vs 94 ng/mL, PCOPD (168 vs 196 ng/mL) subgroups did not achieve statistical significance (P=0.09). Serum CCL-18 levels were significantly higher in COPD patients who had experienced at least one exacerbation during the previous 12 months. Overall, ROC analysis revealed that a serum CCL-18 level of 181.71 ng/mL could differentiate COPD patients with hospitalized exacerbations from those who were not hospitalized with a 88% sensitivity and 88.2% specificity (area under curve: 0.92). Serum CCL-18 level had a strong correlation with the frequency of exacerbations requiring hospitalization (r=0.68, PCOPD, as it is associated with frequency of exacerbations, particularly with severe COPD exacerbations requiring hospitalization, as well as with functional parameters and symptom scores. PMID:28115842

  11. The CCL3L1-CCR5 genotype influences the development of AIDS, but not HIV susceptibility or the response to HAART

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, Tanmoy [Los Alamos National Laboratory; Stanton, Jennifer [NORTHWESTERN UNIV; Kim, Eun - Young [NORTHWESTERN UNIV; Kunstman, Kevin [NORTHWESTERN UNIV; Phair, John [NORTHWESTERN UNIV; Jacobson, Lisa P [JOHNS HOPKINS UNIV; Wolinsky, Steven M [NORTHWESTERN UNIV

    2008-01-01

    A selective advantage against infectious diseases such as HIV/AIDS is associated with differences in the genes relevant to immunity and virus replication. The CC chemokine receptor 5 (CCR5), the principal coreceptor for HIV, and its chemokine ligands, including CCL3L1, influences the CD4+ target cells susceptibility to infection. The CCL3L1 gene is in a region of segmental duplication on the q-arm of human chromosome 17. Increased numbers of CCL3L1 gene copies that affect the gene expression phenotype might have substantial protective effects. Here we show that the population-specific CCL3L1 gene copy number and the CCR5 {Delta}32 protein-inactivating deletion that categorizes the CCL3L1-CCR5 genotype do not influence HIV/AIDS susceptibility or the robustness of immune recovery after the initiation of highly active antiretroviral therapy (HAART).

  12. Study of InGaN/GaN quantum dot systems by TEM techniques and photoluminescence spectroscopy

    International Nuclear Information System (INIS)

    Kashtiban, R J; Bangert, U; Harvey, A J; Sherliker, B; Halsall, M P

    2010-01-01

    InGaN/GaN multilayer quantum dot structures produced by MOCVD techniques on c-plane sapphire were studied by transmission electron microscopy (TEM) and photoluminescence (PL) techniques. Indium fluctuations ranging from 1-4 nm were observed with both energy filtered TEM (EFTEM) and high angle annular dark field (HAADF) scanning TEM. The existence of V-shaped defects with nucleation centres at the termination of threading dislocation were observed in HAADF images. There was also evidence of the formation of large quantum dots at low densities from lattice HRTEM images. This was further confirmed by PL measurements through the observation of a single sharp line at low power with the typical saturation behaviour at higher power excitation.

  13. Rate constant for the reaction of OH with CH3CCl2F (HCFC-141b) determined by relative rate measurements with CH4 and CH3CCl3

    Science.gov (United States)

    Huder, Karin; Demore, William B.

    1993-01-01

    Determination of accurate rate constants for OH abstraction is of great importance for the calculation of lifetimes for HCFCs and their impact on the atmosphere. For HCFC-141b there has been some disagreement in the literature for absolute measurements of this rate constant. In the present work rate constant ratios for HCFC-141b were measured at atmospheric pressure in the temperature range of 298-358 K, with CH4 and CH3CCl3 as reference gases. Ozone was photolyzed at 254 nm in the presence of water vapor to produce OH radicals. Relative depletions of 141b and the reference gases were measured by FTIR. Arrhenius expressions for 141b were derived from each reference gas and found to be in good agreement with each other. The combined expression for HCFC-141b which we recommend is 1.4 x 10 exp -12 exp(-1630/T) with k at 298 K being 5.9 x 10 exp -15 cu cm/molec-s. This value is in excellent agreement with the JPL 92-20 recommendation.

  14. Chemokine CCL2 and chemokine receptor CCR2 in early active multiple sclerosis

    DEFF Research Database (Denmark)

    Sørensen, Torben Lykke; Ransohoff, R M; Strieter, R M

    2004-01-01

    The chemokine monocyte chemoattractant protein (MCP)-1/CCL2 and its receptor CCR2 have been strongly implicated in disease pathogenesis in experimental autoimmune encephalomyelitis, an animal model of multiple sclerosis (MS), whereas data on the CCL2-CCR2 axis are scarce in MS. We studied...... the expression of CCR2 on leukocytes in blood and cerebrospinal fluid (CSF) from patients with monosymptomatic optic neuritis and MS, and the concentration of CCL2 in the CSF from these patients. Results were compared with the results in non-inflammatory neurological controls and were correlated with other...... parameters (magnetic resonance imaging and CSF data). Our findings suggest a limited role for CCL2/CCR2 in early active MS....

  15. Ab Initio Theoretical Studies on the Kinetics of Hydrogen Abstraction Type Reactions of Hydroxyl Radicals with CH3CCl2F and CH3CClF2

    Science.gov (United States)

    Saheb, Vahid; Maleki, Samira

    2018-03-01

    The hydrogen abstraction reactions from CH3Cl2F (R-141b) and CH3CClF2 (R-142b) by OH radicals are studied theoretically by semi-classical transition state theory. The stationary points for the reactions are located by using KMLYP density functional method along with 6-311++G(2 d,2 p) basis set and MP2 method along with 6-311+G( d, p) basis set. Single-point energy calculations are performed by the CBS-Q and G4 combination methods on the geometries optimized at the KMLYP/6-311++G(2 d,2 p) level of theory. Vibrational anharmonicity coefficients, x ij , which are needed for semi-classical transition state theory calculations, are computed at the KMLYP/6-311++G(2 d,2 p) and MP2/6-311+G( d, p) levels of theory. The computed barrier heights are slightly sensitive to the quantum-chemical method. Thermal rate coefficients are computed over the temperature range from 200 to 2000 K and they are shown to be in accordance with available experimental data. On the basis of the computed rate coefficients, the tropospheric lifetime of the CH3CCl2F and CH3CClF2 are estimated to be about 6.5 and 12.0 years, respectively.

  16. Recombinant guinea pig CCL5 (RANTES) differentially modulates cytokine production in alveolar and peritoneal macrophages.

    Science.gov (United States)

    Skwor, Troy A; Cho, Hyosun; Cassidy, Craig; Yoshimura, Teizo; McMurray, David N

    2004-12-01

    The CC chemokine ligand 5 (CCL5; regulated on activation, normal T expressed and secreted) is known to recruit and activate leukocytes; however, its role in altering the responses of host cells to a subsequent encounter with a microbial pathogen has rarely been studied. Recombinant guinea pig (rgp)CCL5 was prepared, and its influence on peritoneal and alveolar macrophage activation was examined by measuring cytokine and chemokine mRNA expression in cells stimulated with rgpCCL5 alone or exposed to rgpCCL5 prior to lipopolysaccharide (LPS) stimulation. Levels of mRNA for guinea pig tumor necrosis factor alpha (TNF-alpha), interleukin (IL)-1beta, CCL2 (monocyte chemoattractant protein-1), and CXC chemokine ligand 8 (IL-8) were analyzed by reverse transcription followed by real-time polymerase chain reaction analysis using SYBR Green. Bioactive TNF-alpha protein concentration was measured using the L929 bioassay. Both macrophage populations displayed significant enhancement of all the genes and TNF-alpha protein levels when stimulated with rgpCCL5, except for CCL2 in alveolar macrophages. When peritoneal or alveolar macrophages were pretreated with rgpCCL5 for 2 h and then exposed to low concentrations of LPS, diminished cytokine and chemokine mRNA levels were apparent at 6 h compared with LPS alone. At the protein level, there was a reduction in TNF-alpha protein at 6 h in the CCL5-pretreated cells compared with LPS alone. These results further support a role for CCL5 in macrophage activation in addition to chemotactic properties and suggest a role in regulating the inflammatory response to LPS in the guinea pig by modulating the production of proinflammatory cytokines by macrophages.

  17. The Chemokine MIP-1α/CCL3 impairs mouse hippocampal synaptic transmission, plasticity and memory.

    Science.gov (United States)

    Marciniak, Elodie; Faivre, Emilie; Dutar, Patrick; Alves Pires, Claire; Demeyer, Dominique; Caillierez, Raphaëlle; Laloux, Charlotte; Buée, Luc; Blum, David; Humez, Sandrine

    2015-10-29

    Chemokines are signaling molecules playing an important role in immune regulations. They are also thought to regulate brain development, neurogenesis and neuroendocrine functions. While chemokine upsurge has been associated with conditions characterized with cognitive impairments, their ability to modulate synaptic plasticity remains ill-defined. In the present study, we specifically evaluated the effects of MIP1-α/CCL3 towards hippocampal synaptic transmission, plasticity and spatial memory. We found that CCL3 (50 ng/ml) significantly reduced basal synaptic transmission at the Schaffer collateral-CA1 synapse without affecting NMDAR-mediated field potentials. This effect was ascribed to post-synaptic regulations, as CCL3 did not impact paired-pulse facilitation. While CCL3 did not modulate long-term depression (LTD), it significantly impaired long-term potentiation (LTP), an effect abolished by Maraviroc, a CCR5 specific antagonist. In addition, sub-chronic intracerebroventricular (icv) injections of CCL3 also impair LTP. In accordance with these electrophysiological findings, we demonstrated that the icv injection of CCL3 in mouse significantly impaired spatial memory abilities and long-term memory measured using the two-step Y-maze and passive avoidance tasks. These effects of CCL3 on memory were inhibited by Maraviroc. Altogether, these data suggest that the chemokine CCL3 is an hippocampal neuromodulator able to regulate synaptic plasticity mechanisms involved in learning and memory functions.

  18. Role of estrogen receptor β selective agonist in ameliorating portal hypertension in rats with CCl4-induced liver cirrhosis.

    Science.gov (United States)

    Zhang, Cheng-Gang; Zhang, Bin; Deng, Wen-Sheng; Duan, Ming; Chen, Wei; Wu, Zhi-Yong

    2016-05-14

    To investigate the role of diarylpropionitrile (DPN), a selective agonist of estrogen receptor β (ERβ), in liver cirrhosis with portal hypertension (PHT) and isolated hepatic stellate cells (HSCs). Female Sprague-Dawley rats were ovariectomized (OVX), and liver cirrhosis with PHT was induced by CCl4 injection. DPN and PHTPP, the selective ERβ agonist and antagonist, were used as drug interventions. Liver fibrosis was assessed by hematoxylin and eosin (HE) and Masson's trichrome staining and by analyzing smooth muscle actin expression. Hemodynamic parameters were determined in vivo using colored microspheres technique. Protein expression and phosphorylation were determined by immunohistochemical staining and Western blot analysis. Messenger RNA levels were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR). Collagen gel contraction assay was performed using gel lattices containing HSCs treated with DPN, PHTPP, or Y-27632 prior to ET-1 addition. Treatment with DPN in vivo greatly lowered portal pressure and improved hemodynamic parameters without affecting mean arterial pressure, which was associated with the attenuation of liver fibrosis and intrahepatic vascular resistance (IHVR). In CCl4-treated rat livers, DPN significantly decreased the expression of RhoA and ROCK II, and even suppressed ROCK II activity. Moreover, DPN remarkedly increased the levels of endothelial nitric oxide synthase (eNOS) and phosphorylated eNOS, and promoted the activities of protein kinase G (PKG), which is an NO effector in the liver. Furthermore, DPN reduced the contractility of activated HSCs in the 3-dimensional stress-relaxed collagen lattices, and decreased the ROCK II activity in activated HSCs. Finally, in vivo/in vitro experiments demonstrated that MLC activity was inhibited by DPN. For OVX rats with liver cirrhosis, DPN suppressed liver RhoA/ROCK signal, facilitated NO/PKG pathways, and decreased IHVR, giving rise to reduced portal pressure. Therefore, DPN

  19. BMP15 Prevents Cumulus Cell Apoptosis Through CCL2 and FBN1 in Porcine Ovaries

    Directory of Open Access Journals (Sweden)

    Bo Zhai

    2013-07-01

    Full Text Available Background: Bone morphogenetic protein-15 (BMP15 is a maternal gene necessary for mammalian reproduction. BMP15 expression increased in oocytes accompanied by follicle growth and development. The function and regulation mechanism of BMP15 in porcine cumulus cell apoptosis process is still unclear now. Methods: In this study, flow cytometry (FCM was used to analyze the effects of BMP15 with different concentrations to cumulus cell apoptosis. High-throughput sequencing technology was carried out to screen regulatory genes linked closely with BMP15. In order to confirm the function of (MCP-1/CCL2 and FBN1 in cumulus cell apoptosis, RNA interference (RNAi method was used to inhibit the expression of (MCP-1/CCL2 and FBN1. Apoptosis and proliferation of cumulus cell treated with siRNA transfection technology were measured by FCM, 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide, quantitative real time-PCR (RT-qPCR and western blotting. Results: The results showed that the apoptosis levels of cumulus cell treated by BMP15 decreased significantly in a dose-dependent manner. The expression of related genes protein 1 (MCP-1/CCL2 and fibrillin1 (FBN1 were both regulated by BMP15. After transfection, the proliferation of porcine cumulus cells increased significantly and apoptosis of cumulus cells was prevented while FBN1 was silenced after BMP15 treatment. The proliferation of cumulus cells decreased significantly and apoptosis rate of cumulus cells increased significantly while CCL2 was silenced. Conclusion: The results obtained in this study firstly demonstrated that CCL2 and FBN1 are important regulatory factors of BMP15 in preventing cumulus cell apoptosis in porcine ovaries.

  20. Complex dynamics in planar two-electron quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Schroeter, Sebastian Josef Arthur

    2013-06-25

    Quantum dots play an important role in a wide range of recent experimental and technological developments. In particular they are promising candidates for realisations of quantum bits and further applications in quantum information theory. The harmonically confined Hooke's atom model is experimentally verified and separates in centre-of-mass and relative coordinates. Findings that are contradictory to this separability call for an extension of the model, in particular changing the confinement potential. In order to study effects of an anharmonic confinement potential on spectral properties of planar two-electron quantum dots a sophisticated numerical approach is developed. Comparison between the Helium atom, Hooke's atom and an anharmonic potential model are undertaken in order to improve the description of quantum dots. Classical and quantum features of complexity and chaos are investigated and used to characterise the dynamics of the system to be mixed regular-chaotic. Influence of decoherence can be described by quantum fidelity, which measures the effect of a perturbation on the time evolution. The quantum fidelity of eigenstates of the system depends strongly on the properties of the perturbation. Several methods for solving the time-dependent Schrödinger equation are implemented and a high level of accuracy for long time evolutions is achieved. The concept of offset entanglement, the entanglement of harmonic models in the noninteracting limit, is introduced. This concept explains different questions raised in the literature for harmonic quantum dot models, recently. It shows that only in the groundstate the electrons are not entangled in the fermionic sense. The applicability, validity, and origin of Hund's first rule in general quantum dot models is further addressed. In fact Hund's first rule is only applicable, and in this case also valid, for one pair of singlet and triplet states in Hooke's atom. For more realistic models of two

  1. Chemokines CXCL10 and CCL2: differential involvement in intrathecal inflammation in multiple sclerosis

    DEFF Research Database (Denmark)

    Sørensen, T.L.; Sellebjerg, F; Jensen, C.V.

    2001-01-01

    leukocyte count, the CSF concentration of neopterin, matrix metalloproteinase (MMP)-9, and intrathecal IgG and IgM synthesis. The concentration of CCL2 increased between baseline for 3 weeks in both groups, more distinctly so in patients treated with methylprednisolone. CCL2 correlated negatively with MMP-9...... patients in relapse, whilst levels of CCL2 (MCP-1) were reduced. Here, we report a serial analysis of CSF CXCL10 and CCL2 concentrations in 22 patients with attacks of MS or acute optic neuritis (ON) treated with methylprednisolone, and 26 patients treated with placebo in two randomized controlled trials....... Chemokine concentrations were measured by enzyme linked immunosorbent assay (ELISA) in CSF obtained at baseline and after 3 weeks, and were compared with other measures of intrathecal inflammation. At baseline CSF concentrations of CCL2 were significantly lower in the patient group than in controls...

  2. Basophils, high-affinity IgE receptors, and CCL2 in human anaphylaxis.

    Science.gov (United States)

    Korosec, Peter; Turner, Paul J; Silar, Mira; Kopac, Peter; Kosnik, Mitja; Gibbs, Bernhard F; Shamji, Mohamed H; Custovic, Adnan; Rijavec, Matija

    2017-09-01

    The role of basophils in anaphylaxis is unclear. We sought to investigate whether basophils have an important role in human anaphylaxis. In an emergency department study we recruited 31 patients with acute anaphylaxis, predominantly to Hymenoptera venom. We measured expression of basophil activation markers (CD63 and CD203c); the absolute number of circulating basophils; whole-blood FCER1A, carboxypeptidase A3 (CPA3), and L-histidine decarboxylase (HDC) gene expression; and serum markers (CCL2, CCL5, CCL11, IL-3, and thymic stromal lymphopoietin) at 3 time points (ie, during the anaphylactic episode and in convalescent samples 7 and 30 days later). We recruited 134 patients with Hymenoptera allergy and 76 healthy control subjects for comparison. We then investigated whether the changes observed during venom-related anaphylaxis also occur during allergic reactions to food in 22 patients with peanut allergy undergoing double-blind, placebo-controlled food challenge to peanut. The number of circulating basophils was significantly lower during anaphylaxis (median, 3.5 cells/μL) than 7 and 30 days later (17.5 and 24.7 cells/μL, P < .0001) and compared with those in patients with venom allergy and healthy control subjects (21 and 23.4 cells/μL, P < .0001). FCER1A expression during anaphylaxis was also significantly lower than in convalescent samples (P ≤ .002) and control subjects with venom allergy (P < .0001). CCL2 levels (but not those of other serum markers) were significantly higher during anaphylaxis (median, 658 pg/mL) than in convalescent samples (314 and 311 pg/mL at 7 and 30 days, P < .001). Peanut-induced allergic reactions resulted in a significant decrease in circulating basophil counts compared with those in prechallenge samples (P = .016), a decrease in FCER1A expression (P = .007), and an increase in CCL2 levels (P = .003). Our findings imply an important and specific role for basophils in the pathophysiology of human

  3. Photolysis of Br2 in CCl4 studied by time-resolved X-ray scattering.

    Science.gov (United States)

    Kong, Qingyu; Lee, Jae Hyuk; Lo Russo, Manuela; Kim, Tae Kyu; Lorenc, Maciej; Cammarata, Marco; Bratos, Savo; Buslaps, Thomas; Honkimaki, Veijo; Ihee, Hyotcherl; Wulff, Michael

    2010-03-01

    A time-resolved X-ray solution scattering study of bromine molecules in CCl(4) is presented as an example of how to track atomic motions in a simple chemical reaction. The structures of the photoproducts are tracked during the recombination process, geminate and non-geminate, from 100 ps to 10 micros after dissociation. The relaxation of hot Br(2)(*) molecules heats the solvent. At early times, from 0.1 to 10 ns, an adiabatic temperature rise is observed, which leads to a pressure gradient that forces the sample to expand. The expansion starts after about 10 ns with the laser beam sizes used here. When thermal artefacts are removed by suitable scaling of the transient solvent response, the excited-state solute structures can be obtained with high fidelity. The analysis shows that 30% of Br(2)(*) molecules recombine directly along the X potential, 60% are trapped in the A/A' state with a lifetime of 5.5 ns, and 10% recombine non-geminately via diffusive motion in about 25 ns. The Br-Br distance distribution in the A/A' state peaks at 3.0 A.

  4. Tanshinol ameliorates CCl4-induced liver fibrosis in rats through the regulation of Nrf2/HO-1 and NF-κB/IκBα signaling pathway

    Directory of Open Access Journals (Sweden)

    Wang R

    2018-05-01

    Full Text Available Rong Wang,* Jing Wang,* Fuxing Song, Shengnan Li, Yongfang Yuan Department of Pharmacy, Shanghai 9th People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China *These authors contributed equally to this work Abstract: Tanshinol, a water-soluble component isolated from Salvia miltiorrhiza Bunge, has a variety of biological activities involving anti-fibrotic effect. However, the exact role and the underlying mechanisms remain largely unclear. This study mainly focused on the anti-hepatic fibrotic activities and mechanisms of tanshinol on carbon tetrachloride (CCl4-induced liver fibrosis in rats via anti-oxidative and anti-inflammation pathways. The rats were divided into 4 groups as follows: control, model, tanshinol 20 mg/kg, and tanshinol 40 mg/kg. Except for the control group, CCl4 was used to induce liver fibrosis processing for 8 weeks, meanwhile rats in tanshinol groups were intraperitoneally injected with additional tanshinol. Control group simultaneously received the same volumes of olive oil and saline. The potentially protective effect and mechanisms of tanshinol on liver fibrosis in rats were evaluated. The serum levels of alanine aminotransferase, aspartate aminotransferase, and total bilirubin were obviously lower in the tanshinol treatment groups related to model group. Compared with the model group, the levels of hyaluronic acid, type IV collagen, Laminin (LN, and procollagen III peptide (PIIIP in serum were significantly decreased after tanshinol treatment. Furthermore, tanshinol could regulate Nrf2/HO-1 signaling pathway and increase the level of superoxide dismutase (SOD and glutathione peroxidase (GSH-Px, and also decrease the level of malondialdehyde (MDA to against damage induced by oxidative stress. Simultaneously tanshinol could regulate nuclear factor kappa B signaling pathway to inhibit expression of inflammation factors, including transforming growth factor-β, tumor necrosis factor-α, Cox-2

  5. Rapid transport of CCL11 across the blood-brain barrier: regional variation and importance of blood cells.

    Science.gov (United States)

    Erickson, Michelle A; Morofuji, Yoichi; Owen, Joshua B; Banks, William A

    2014-06-01

    Increased blood levels of the eotaxin chemokine C-C motif ligand 11 (CCL11) in aging were recently shown to negatively regulate adult hippocampal neurogenesis. How circulating CCL11 could affect the central nervous system (CNS) is not clear, but one possibility is that it can cross the blood-brain barrier (BBB). Here, we show that CCL11 undergoes bidirectional transport across the BBB. Transport of CCL11 from blood into whole brain (influx) showed biphasic kinetics, with a slow phase preceding a rapid phase of uptake. We found that the slow phase was explained by binding of CCL11 to cellular components in blood, whereas the rapid uptake phase was mediated by direct interactions with the BBB. CCL11, even at high doses, did not cause BBB disruption. All brain regions except striatum showed a delayed rapid-uptake phase. Striatum had only an early rapid-uptake phase, which was the fastest of any brain region. We also observed a slow but saturable transport system for CCL11 from brain to blood. C-C motif ligand 3 (CCR3), an important receptor for CCL11, did not facilitate CCL11 transport across the BBB, although high concentrations of a CCR3 inhibitor increased brain uptake without causing BBB disruption. Our results indicate that CCL11 in the circulation can access many regions of the brain outside of the neurogenic niche via transport across the BBB. This suggests that blood-borne CCL11 may have important physiologic functions in the CNS and implicates the BBB as an important regulator of physiologic versus pathologic effects of this chemokine.

  6. HPV16-E7 expression in squamous epithelium creates a local immune suppressive environment via CCL2- and CCL5- mediated recruitment of mast cells.

    Directory of Open Access Journals (Sweden)

    Anne-Sophie Bergot

    2014-10-01

    Full Text Available Human Papillomavirus (HPV 16 E7 protein promotes the transformation of HPV infected epithelium to malignancy. Here, we use a murine model in which the E7 protein of HPV16 is expressed as a transgene in epithelium to show that mast cells are recruited to the basal layer of E7-expressing epithelium, and that this recruitment is dependent on the epithelial hyperproliferation induced by E7 by inactivating Rb dependent cell cycle regulation. E7 induced epithelial hyperplasia is associated with increased epidermal secretion of CCL2 and CCL5 chemokines, which attract mast cells to the skin. Mast cells in E7 transgenic skin, in contrast to those in non-transgenic skin, exhibit degranulation. Notably, we found that resident mast cells in E7 transgenic skin cause local immune suppression as evidenced by tolerance of E7 transgenic skin grafts when mast cells are present compared to the rejection of mast cell-deficient E7 grafts in otherwise competent hosts. Thus, our findings suggest that mast cells, recruited towards CCL2 and CCL5 expressed by epithelium induced to proliferate by E7, may contribute to an immunosuppressive environment that enables the persistence of HPV E7 protein induced pre-cancerous lesions.

  7. Andrographis paniculata ameliorates carbon tetrachloride (CCl(4))-dependent hepatic damage and toxicity: diminution of oxidative stress.

    Science.gov (United States)

    Koh, Pei Hoon; Mokhtar, Ruzaidi Azli Mohd; Iqbal, Mohammad

    2011-01-01

    Andrographis paniculata (hempedu bumi) is a plant that possesses many medicinal values in treating several diseases and for health care maintenance. However, its hepatoprotective activity and mechanism of action have not been fully investigated. Therefore, this study aimed to evaluate the hepatoprotective effects of A. paniculata and its mechanism of action in rats. Carbon tetrachloride (CCl(4)) challenge of rats at a dose of 1.2 ml/kg body weight-induced oxidative stress in the liver. This was evidenced by augmentation in lipid peroxidation, which was accompanied by a decrease in the activities of antioxidant enzymes and depletion in the level of reduced glutathione (P paniculata (P paniculata to scavenge the 2,2-Diphenyl-2-picrylhydrazyl radical was determined through its EC(50) value. The EC(50) value of A. paniculata was 583.60 ± 4.25 µg/ml. In addition, A. paniculata was found to contain 65.37 ± 1.20 mg/g total phenolics expressed as gallic acid equivalent. From these studies, it is concluded that A. paniculata could be used as a hepatoprotective agent and possesses the potential to treat or prevent degenerative diseases where oxidative stress is implicated.

  8. pVT-Second Virial Coefficients B(T ), Viscosity η(T ), and Self-Diffusion ρD(T) of the Gases: BF3, CF4, SiF4, CCl4, SiCl4, SF6, MoF6, WF6, UF6, C(CH3)4, and Si(CH3)4 Determined by Means of an Isotropic Temperature-Dependent Potential

    Science.gov (United States)

    Zarkova, L.; Hohm, U.

    2002-03-01

    We present results on self-consistent calculations of second pVT-virial coefficients B(T), viscosity data η(T), and diffusion coefficients ρD(T) for eleven heavy globular gases: boron trifluoride (BF3), carbon tetrafluoride (CF4), silicon tetrafluoride (SiF4), carbon tetrachloride (CCl4), silicon tetrachloride (SiCl4), sulfur hexafluoride (SF6), molybdenum hexafluoride (MoF6), tungsten hexafluoride (WF6), uranium hexafluoride (UF6), tetramethyl methane (C(CH3)4, TMM), and tetramethyl silane (Si(CH3)4, TMS). The calculations are performed mainly in the temperature range between 200 and 900 K by means of isotropic n-6 potentials with temperature-dependent separation rm(T) and potential well depth ɛ(T). The potential parameters at T=0 K (ɛ, rm, n) and the enlargement of the first level radii δ are obtained solving an ill-posed problem of minimizing the squared deviations between experimental and calculated values normalized to their relative experimental error. The temperature dependence of the potential is obtained as a result of the influence of vibrational excitation on binary interactions. This concept of the isotropic temperature-dependent potential (ITDP) is presented in detail where gaseous SF6 will serve as an example. The ITDP is subsequently applied to all other gases. This approach and the main part of the results presented here have already been published during 1996-2000. However, in some cases the data are upgraded due to the recently improved software (CF4, SF6) and newly found experimental data (CF4, SiF4, CCl4, SF6).

  9. 3,4-Phenylenedioxythiophene (PheDOT) Based Hole-Transporting Materials for Perovskite Solar Cells.

    Science.gov (United States)

    Chen, Jian; Chen, Bai-Xue; Zhang, Fang-Shuai; Yu, Hui-Juan; Ma, Shuang; Kuang, Dai-Bin; Shao, Guang; Su, Cheng-Yong

    2016-04-05

    Two new electron-rich molecules based on 3,4-phenylenedioxythiophene (PheDOT) were synthesized and successfully adopted as hole-transporting materials (HTMs) in perovskite solar cells (PSCs). X-ray diffraction, absorption spectra, photoluminescence spectra, electrochemical properties, thermal stabilities, hole mobilities, conductivities, and photovoltaic parameters of PSCs based on these two HTMs were compared with each other. By introducing methoxy substituents into the main skeleton, the energy levels of PheDOT-core HTM were tuned to match with the perovskite, and its hole mobility was also improved (1.33×10(-4)  cm(2)  V(-1)  s(-1) , being higher than that of spiro-OMeTAD, 2.34×10(-5)  cm(2)  V(-1)  s(-1)). The PSC based on MeO-PheDOT as HTM exhibits a short-circuit current density (Jsc) of 18.31 mA cm(-2) , an open-circuit potential (Voc ) of 0.914 V, and a fill factor (FF) of 0.636, yielding an encouraging power conversion efficiency (PCE) of 10.64 % under AM 1.5G illumination. These results give some insight into how the molecular structures of HTMs affect their performances and pave the way for developing high-efficiency and low-cost HTMs for PSCs. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Transforming Growth Factor-β and Interleukin-1β Signaling Pathways Converge on the Chemokine CCL20 Promoter.

    Science.gov (United States)

    Brand, Oliver J; Somanath, Sangeeta; Moermans, Catherine; Yanagisawa, Haruhiko; Hashimoto, Mitsuo; Cambier, Stephanie; Markovics, Jennifer; Bondesson, Andrew J; Hill, Arthur; Jablons, David; Wolters, Paul; Lou, Jianlong; Marks, James D; Baron, Jody L; Nishimura, Stephen L

    2015-06-05

    CCL20 is the only chemokine ligand for the chemokine receptor CCR6, which is expressed by the critical antigen presenting cells, dendritic cells. Increased expression of CCL20 is likely involved in the increased recruitment of dendritic cells observed in fibroinflammatory diseases such as chronic obstructive pulmonary disease (COPD). CCL20 expression is increased by the proinflammatory cytokine IL-1β. We have determined that IL-1β-dependent CCL20 expression is also dependent on the multifunctional cytokine TGF-β. TGF-β is expressed in a latent form that must be activated to function, and activation is achieved through binding to the integrin αvβ8 (itgb8). Here we confirm correlative increases in αvβ8 and IL-1β with CCL20 protein in lung parenchymal lysates of a large cohort of COPD patients. How IL-1β- and αvβ8-mediated TGF-β activation conspire to increase fibroblast CCL20 expression remains unknown, because these pathways have not been shown to directly interact. We evaluate the 5'-flanking region of CCL20 to determine that IL-1β-driven CCL20 expression is dependent on αvβ8-mediated activation of TGF-β. We identify a TGF-β-responsive element (i.e. SMAD) located on an upstream enhancer of the human CCL20 promoter required for efficient IL-1β-dependent CCL20 expression. By chromatin immunoprecipitation, this upstream enhancer complexes with the p50 subunit of NF-κB on a NF-κB-binding element close to the transcriptional start site of CCL20. These interactions are confirmed by electromobility shift assays in nuclear extracts from human lung fibroblasts. These data define a mechanism by which αvβ8-dependent activation of TGF-β regulates IL-1β-dependent CCL20 expression in COPD. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  11. CCL5 promotes VEGF-C production and induces lymphangiogenesis by suppressing miR-507 in human chondrosarcoma cells.

    Science.gov (United States)

    Wang, Li-Hong; Lin, Chih-Yang; Liu, Shih-Chia; Liu, Guan-Ting; Chen, Yen-Ling; Chen, Jih-Jung; Chan, Chia-Han; Lin, Ting-Yi; Chen, Chi-Kuan; Xu, Guo-Hong; Chen, Shiou-Sheng; Tang, Chih-Hsin; Wang, Shih-Wei

    2016-06-14

    Chondrosarcoma is the second most frequently occurring type of bone malignancy that is characterized by the distant metastasis propensity. Vascular endothelial growth factor-C (VEGF-C) is the major lymphangiogenic factor, and makes crucial contributions to tumor lymphangiogenesis and lymphatic metastasis. Chemokine CCL5 has been reported to facilitate angiogenesis and metastasis in chondrosarcoma. However, the effect of chemokine CCL5 on VEGF-C regulation and lymphangiogenesis in chondrosarcoma has largely remained a mystery. In this study, we showed a clinical correlation between CCL5 and VEGF-C as well as tumor stage in human chondrosarcoma tissues. We further demonstrated that CCL5 promoted VEGF-C expression and secretion in human chondrosarcoma cells. The conditioned medium (CM) from CCL5-overexpressed cells significantly induced tube formation of human lymphatic endothelial cells (LECs). Mechanistic investigations showed that CCL5 activated VEGF-C-dependent lymphangiogenesis by down-regulating miR-507. Moreover, inhibiting CCL5 dramatically reduced VEGF-C and lymphangiogenesis in the chondrosarcoma xenograft animal model. Collectively, we document for the first time that CCL5 induces tumor lymphangiogenesis by the induction of VEGF-C in human cancer cells. Our present study reveals miR-507/VEGF-C signaling as a novel mechanism in CCL5-mediated tumor lymphangiogenesis. Targeting both CCL5 and VEGF-C pathways might serve as the potential therapeutic strategy to block cancer progression and metastasis in chondrosarcoma.

  12. Pseudogenization of the MCP-2/CCL8 chemokine gene in European rabbit (genus Oryctolagus, but not in species of Cottontail rabbit (Sylvilagus and Hare (Lepus

    Directory of Open Access Journals (Sweden)

    van der Loo Wessel

    2012-08-01

    Full Text Available Abstract Background Recent studies in human have highlighted the importance of the monocyte chemotactic proteins (MCP in leukocyte trafficking and their effects in inflammatory processes, tumor progression, and HIV-1 infection. In European rabbit (Oryctolagus cuniculus one of the prime MCP targets, the chemokine receptor CCR5 underwent a unique structural alteration. Until now, no homologue of MCP-2/CCL8a, MCP-3/CCL7 or MCP-4/CCL13 genes have been reported for this species. This is interesting, because at least the first two genes are expressed in most, if not all, mammals studied, and appear to be implicated in a variety of important chemokine ligand-receptor interactions. By assessing the Rabbit Whole Genome Sequence (WGS data we have searched for orthologs of the mammalian genes of the MCP-Eotaxin cluster. Results We have localized the orthologs of these chemokine genes in the genome of European rabbit and compared them to those of leporid genera which do (i.e. Oryctolagus and Bunolagus or do not share the CCR5 alteration with European rabbit (i.e. Lepus and Sylvilagus. Of the Rabbit orthologs of the CCL8, CCL7, and CCL13 genes only the last two were potentially functional, although showing some structural anomalies at the protein level. The ortholog of MCP-2/CCL8 appeared to be pseudogenized by deleterious nucleotide substitutions affecting exon1 and exon2. By analyzing both genomic and cDNA products, these studies were extended to wild specimens of four genera of the Leporidae family: Oryctolagus, Bunolagus, Lepus, and Sylvilagus. It appeared that the anomalies of the MCP-3/CCL7 and MCP-4/CCL13 proteins are shared among the different species of leporids. In contrast, whereas MCP-2/CCL8 was pseudogenized in every studied specimen of the Oryctolagus - Bunolagus lineage, this gene was intact in species of the Lepus - Sylvilagus lineage, and was, at least in Lepus, correctly transcribed. Conclusion The biological function of a gene was often

  13. CCL28 induces mucosal homing of HIV-1-specific IgA-secreting plasma cells in mice immunized with HIV-1 virus-like particles.

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    Veronica Rainone

    Full Text Available Mucosae-associated epithelial chemokine (MEC or CCL28 binds to CCR3 and CCR10 and recruits IgA-secreting plasma cells (IgA-ASCs in the mucosal lamina propria. The ability of this chemokine to enhance migration of IgA-ASCs to mucosal sites was assessed in a mouse immunization model using HIV-1(IIIB Virus-like particles (VLPs. Mice receiving either HIV-1(IIIB VLPs alone, CCL28 alone, or the irrelevant CCL19 chemokine were used as controls. Results showed a significantly increased CCR3 and CCR10 expression on CD19(+ splenocytes of HIV-1(IIIB VPL-CCL28-treated mice. HIV-1 Env-specific IFN-γ, IL-4 and IL-5 production, total IgA, anti-Env IgA as well as gastro-intestinal mucosal IgA-secreting plasma cells were also significantly augmented in these mice. Notably, sera and vaginal secretions from HIV-1(IIIB VLP-CCL28-treated mice exhibited an enhanced neutralizing activity against both a HIV-1/B-subtype laboratory strain and a heterologous HIV-1/C-subtype primary isolate. These data suggest that CCL28 could be useful in enhancing the IgA immune response that will likely play a pivotal role in prophylactic HIV vaccines.

  14. Association of CCL11 promoter polymorphisms with schizophrenia in a Korean population.

    Science.gov (United States)

    Kang, Won Sub; Kim, Young Jong; Park, Hae Jeong; Kim, Su Kang; Paik, Jong-Woo; Kim, Jong Woo

    2018-05-20

    Immunological alterations and dysregulation of the inflammatory response have been suggested to play a crucial role in schizophrenia pathophysiology. Growing evidence supports the involvement of chemokines in brain development, thus many chemokines have been studied in relation with schizophrenia. The C-C motif chemokine ligand 11 (CCL11) has been shown to be related with synaptic plasticity and neurogenesis. Moreover, altered levels of CCL11 have been observed in schizophrenia patients. Therefore, we examined whether single nucleotide polymorphisms (SNPs) of the CCL11 in the promoter region contribute to susceptibility to schizophrenia. Four promoter SNPs [rs17809012 (-384T>C), rs16969415 (-426C>T), rs17735961 (-488C>A), and rs4795896 (576G>A)] were genotyped in 254 schizophrenia patients and 405 control subjects using Fluidigm SNPtype assays. The genotype frequency of CCL11 rs4795896 (-576G>A) showed significant association with schizophrenia in a recessive model (AA vs. GG/AG, p schizophrenia (p schizophrenia (p = 0.0044, p schizophrenia in a Korean population. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. CCL2-ethanol interactions and hippocampal synaptic protein expression in a transgenic mouse model

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    Donna eGruol

    2014-04-01

    Full Text Available Chronic exposure to ethanol produces a number of detrimental effects on behavior. Neuroadaptive changes in brain structure or function underlie these behavioral changes and may be transient or persistent in nature. Central to the functional changes are alterations in the biology of neuronal and glial cells of the brain. Recent data show that ethanol induces glial cells of the brain to produce elevated levels of neuroimmune factors including CCL2, a key innate immune chemokine. Depending on the conditions of ethanol exposure, the upregulated levels of CCL2 can be transient or persistent and outlast the period of ethanol exposure. Importantly, results indicate that the upregulated levels of CCL2 may lead to CCL2-ethanol interactions that mediate or regulate the effects of ethanol on the brain. Glial cells are in close association with neurons and regulate many neuronal functions. Therefore, effects of ethanol on glial cells may underlie some of the effects of ethanol on neurons. To investigate this possibility, we are studying the effects of chronic ethanol on hippocampal synaptic function in a transgenic mouse model that expresses elevated levels of CCL2 in the brain through enhanced glial expression, a situation know to occur in alcoholics. Both CCL2 and ethanol have been reported to alter synaptic function in the hippocampus. In the current study, we determined if interactions are evident between CCL2 and ethanol at level of hippocampal synaptic proteins. Two ethanol exposure paradigms were used; the first involved ethanol exposure by drinking and the second involved ethanol exposure in a paradigm that combines drinking plus ethanol vapor. The first paradigm does not produce dependence on ethanol, whereas the second paradigm is commonly used to produce ethanol dependence. Results show modest effects of both ethanol exposure paradigms on the level of synaptic proteins in the hippocampus of CCL2 transgenic mice compared with their non

  16. Modulation of pathogen-induced CCL20 secretion from HT-29 human intestinal epithelial cells by commensal bacteria.

    LENUS (Irish Health Repository)

    Sibartie, Shomik

    2009-01-01

    BACKGROUND: Human intestinal epithelial cells (IECs) secrete the chemokine CCL20 in response to infection by various enteropathogenic bacteria or exposure to bacterial flagellin. CCL20 recruits immature dendritic cells and lymphocytes to target sites. Here we investigated IEC responses to various pathogenic and commensal bacteria as well as the modulatory effects of commensal bacteria on pathogen-induced CCL20 secretion. HT-29 human IECs were incubated with commensal bacteria (Bifidobacterium infantis or Lactobacillus salivarius), or with Salmonella typhimurium, its flagellin, Clostridium difficile, Mycobacterium paratuberculosis, or Mycobacterium smegmatis for varying times. In some studies, HT-29 cells were pre-treated with a commensal strain for 2 hr prior to infection or flagellin stimulation. CCL20 and interleukin (IL)-8 secretion and nuclear factor (NF)-kappaB activation were measured using enzyme-linked immunosorbent assays. RESULTS: Compared to untreated cells, S. typhimurium, C. difficile, M. paratuberculosis, and flagellin activated NF-kappaB and stimulated significant secretion of CCL20 and IL-8 by HT-29 cells. Conversely, B. infantis, L. salivarius or M. smegmatis did not activate NF-kappaB or augment CCL20 or IL-8 production. Treatment with B. infantis, but not L. salivarius, dose-dependently inhibited the baseline secretion of CCL20. In cells pre-treated with B. infantis, C. difficile-, S. typhimurium-, and flagellin-induced CCL20 were significantly attenuated. B. infantis did not limit M. Paratuberculosis-induced CCL20 secretion. CONCLUSION: This study is the first to demonstrate that a commensal strain can attenuate CCL20 secretion in HT-29 IECs. Collectively, the data indicate that M. paratuberculosis may mediate mucosal damage and that B. infantis can exert immunomodulatory effects on IECs that mediate host responses to flagellin and flagellated enteric pathogens.

  17. Transgenic Mouse Model Harboring the Transcriptional Fusion Ccl20-Luciferase as a Novel Reporter of Pro-Inflammatory Response

    Science.gov (United States)

    Crispo, Martina; Van Maele, Laurye; Tabareau, Julien; Cayet, Delphine; Errea, Agustina; Ferreira, Ana María; Rumbo, Martin; Sirard, Jean Claude

    2013-01-01

    The chemokine CCL20, the unique ligand of CCR6 functions as an attractant of immune cells. Expression of CCL20 is induced by Toll-like Receptor (TLR) signaling or proinflammatory cytokine stimulation. However CCL20 is also constitutively produced at specific epithelial sites of mucosa. This expression profile is achieved by transcriptional regulation. In the present work we characterized regulatory features of mouse Ccl20 gene. Transcriptional fusions between the mouse Ccl20 promoter and the firefly luciferase (luc) encoding gene were constructed and assessed in in vitro and in vivo assays. We found that liver CCL20 expression and luciferase activity were upregulated by systemic administration of the TLR5 agonist flagellin. Using shRNA and dominant negative form specific for mouse TLR5, we showed that this expression was controlled by TLR5. To address in situ the regulation of gene activity, a transgenic mouse line harboring a functional Ccl20-luc fusion was generated. The luciferase expression was highly concordant with Ccl20 expression in different tissues. Our data indicate that the transgenic mouse model can be used to monitor activation of innate response in vivo. PMID:24265691

  18. Identification of CCL5/RANTES as a novel contraction-reducible myokine in mouse skeletal muscle.

    Science.gov (United States)

    Ishiuchi, Yuri; Sato, Hitoshi; Komatsu, Narumi; Kawaguchi, Hideo; Matsuwaki, Takashi; Yamanouchi, Keitaro; Nishihara, Masugi; Nedachi, Taku

    2018-03-17

    Skeletal muscle is an endocrine organ that secretes several proteins, which are collectively termed myokines. Although many studies suggest that exercise regulates myokine secretion, the underlying mechanisms remain unclear and all the exercise-dependent myokines have not yet been identified. Therefore, in this study, we attempted to identify novel exercise-dependent myokines by using our recently developed in vitro contractile model. Differentiated C2C12 myotubes were cultured with or without electrical pulse stimulation (EPS) for 24 h to induce cell contraction, and the myokines secreted in conditioned medium were analyzed using a cytokine array. Although most myokine secretions were not affected by EPS, the secretion of Chemokine (C-C motif) ligand 5 (CCL5) (regulated on activation, normal T cell expressed and secreted (RANTES)) was significantly reduced by EPS. This was further confirmed by ELISA and quantitative PCR. Contraction-dependent calcium transients and activation of 5'-AMP activating protein kinase (AMPK) appears to be involved in this decrease, as the chelating Ca 2+ by EGTA blocked contraction-dependent CCL5 reduction, whereas the pharmacological activation of AMPK significantly reduced it. However, Ccl5 gene expression was increased by AMPK activation, suggesting that AMPK-dependent CCL5 decrease occurred via post-transcriptional regulation. Finally, mouse experiments revealed that voluntary wheel-running exercise reduced serum CCL5 levels and Ccl5 gene expression in the fast-twitch muscles. Overall, our study provides the first evidence of an exercise-reducible myokine, CCL5, in the mouse skeletal muscle. Although further studies are required to understand the precise roles of the skeletal muscle cell contraction-induced decrease in CCL5, this decrease may explain some exercise-dependent physiological changes such as those in immune responses. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. Monocyte-derived dendritic cells exposed to Der p 1 allergen enhance the recruitment of Th2 cells: major involvement of the chemokines TARC/CCL17 and MDC/CCL22

    NARCIS (Netherlands)

    Hammad, Hamida; Smits, Hermelijn H.; Ratajczak, Céline; Nithiananthan, Asokananthan; Wierenga, Eddy A.; Stewart, Geoffrey A.; Jacquet, Alain; Tonnel, Andre-Bernard; Pestel, Joël

    2003-01-01

    Dendritic cells (DC) are potent antigen - presenting cells that can orientate the immune response towards a Th1 or a Th2 type. DC produce chemokines that are involved in the recruitment of either Th1 cells, such as IP10 (CXCL10), Th2 cells such as TARC (CCL17) and MDC (CCL22), or non-polarized T

  20. CCL: console command language, RSX11M V4. 0, V7. OC tutorial

    Energy Technology Data Exchange (ETDEWEB)

    Downward, J. G.

    1981-01-01

    The normal user interface to an RSX11M operating system is via MCR (Monitor Console Routine). If terminal input is not specifically requested by a task, all data or commands typed in at a user's terminal, are sent by the terminal driver to MCR for decoding. The MCR task (and its child ...SYS) decode user commands (ACT, ABORT,RUN, DEV, ETC.). Tasks installed with special names of the form ...XYZ are treated as an external MCR command. Hence if a user types, XYZ COMMANDLINE, the commandline in its entirety (or at least up to 79 characters) is sent as input to the task ...XYZ. This is the conventional way of supplying most system commands and controlling the operation of the RSX11M utility program. The limitations of this method are: (1) each task must be installed to get MCR command lines; (2) each installed task uses valuable POOL space; (3) only privileged users can INSTALL and REMOVE tasks; and (4) non-privileged users are restricted to RUNning non-installed tasks. To solve this problem, a user tailorable Console Command Language (CCL) has been implemented which allows each user to have a private task control language to pass command lines to tasks that are not installed in th system as external MCR commands.

  1. Bovine CCL28 Mediates Chemotaxis via CCR10 and Demonstrates Direct Antimicrobial Activity against Mastitis Causing Bacteria.

    Directory of Open Access Journals (Sweden)

    Kyler B Pallister

    Full Text Available In addition to the well characterized function of chemokines in mediating the homing and accumulation of leukocytes to tissues, some chemokines also exhibit potent antimicrobial activity. Little is known of the potential role of chemokines in bovine mammary gland health and disease. The chemokine CCL28 has previously been shown to play a key role in the homing and accumulation of IgA antibody secreting cells to the lactating murine mammary gland. CCL28 has also been shown to act as an antimicrobial peptide with activity demonstrated against a wide range of pathogens including bacteria, fungi and protozoans. Here we describe the cloning and function of bovine CCL28 and document the concentration of this chemokine in bovine milk. Bovine CCL28 was shown to mediate cellular chemotaxis via the CCR10 chemokine receptor and exhibited antimicrobial activity against a variety of bovine mastitis causing organisms. The concentration of bovine CCL28 in milk was found to be highly correlated with the lactation cycle. Highest concentrations of CCL28 were observed soon after parturition, with levels decreasing over time. These results suggest a potential role for CCL28 in the prevention/resolution of bovine mastitis.

  2. AMP-activated protein kinase activation mediates CCL3-induced cell migration and matrix metalloproteinase-2 expression in human chondrosarcoma

    Science.gov (United States)

    2013-01-01

    Chemokine (C-C motif) ligand 3 (CCL3), also known as macrophage inflammatory protein-1α, is a cytokine involved in inflammation and activation of polymorphonuclear leukocytes. CCL3 has been detected in infiltrating cells and tumor cells. Chondrosarcoma is a highly malignant tumor that causes distant metastasis. However, the effect of CCL3 on human chondrosarcoma metastasis is still unknown. Here, we found that CCL3 increased cellular migration and expression of matrix metalloproteinase (MMP)-2 in human chondrosarcoma cells. Pre-treatment of cells with the MMP-2 inhibitor or transfection with MMP-2 specific siRNA abolished CCL3-induced cell migration. CCL3 has been reported to exert its effects through activation of its specific receptor, CC chemokine receptor 5 (CCR5). The CCR5 and AMP-activated protein kinase (AMPK) inhibitor or siRNA also attenuated CCL3-upregulated cell motility and MMP-2 expression. CCL3-induced expression of MMP-2 and migration were also inhibited by specific inhibitors, and inactive mutants of AMPK, p38 mitogen activated protein kinase (p38 or p38-MAPK), and nuclear factor κB (NF-κB) cascades. On the other hand, CCL3 treatment demonstrably activated AMPK, p38, and NF-κB signaling pathways. Furthermore, the expression levels of CCL3, CCR5, and MMP-2 were correlated in human chondrosarcoma specimens. Taken together, our results indicate that CCL3 enhances the migratory ability of human chondrosarcoma cells by increasing MMP-2 expression via the CCR5, AMPK, p38, and NF-κB pathways. PMID:24047437

  3. CCL21 Cancer Immunotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Yuan, E-mail: yuanlin@mednet.ucla.edu [Department of Head and Neck Surgery, David Geffen School of Medicine at UCLA, 10833 Le Conte Avenue, Los Angeles, CA 90095 (United States); Jonsson Comprehensive Cancer Center, David Geffen School of Medicine at UCLA, 10833 Le Conte Avenue, Los Angeles, CA 90095 (United States); UCLA Head and Neck Cancer Program, David Geffen School of Medicine at UCLA, 10833 Le Conte Avenue, Los Angeles, CA 90095 (United States); Clinical and Translational Science Institute, David Geffen School of Medicine at UCLA, 10833 Le Conte Avenue, Los Angeles, CA 90095 (United States); Division of Pulmonary and Critical Care Medicine, Department of Medicine, David Geffen School of Medicine at UCLA, 37-131 CHS, 10833 Le Conte Avenue, Los Angeles, CA 90095 (United States); Sharma, Sherven [Jonsson Comprehensive Cancer Center, David Geffen School of Medicine at UCLA, 10833 Le Conte Avenue, Los Angeles, CA 90095 (United States); Clinical and Translational Science Institute, David Geffen School of Medicine at UCLA, 10833 Le Conte Avenue, Los Angeles, CA 90095 (United States); Division of Pulmonary and Critical Care Medicine, Department of Medicine, David Geffen School of Medicine at UCLA, 37-131 CHS, 10833 Le Conte Avenue, Los Angeles, CA 90095 (United States); Veterans’ Affairs Greater Los Angeles Healthcare System, Los Angeles, CA 90073 (United States); John, Maie St. [Department of Head and Neck Surgery, David Geffen School of Medicine at UCLA, 10833 Le Conte Avenue, Los Angeles, CA 90095 (United States); Jonsson Comprehensive Cancer Center, David Geffen School of Medicine at UCLA, 10833 Le Conte Avenue, Los Angeles, CA 90095 (United States); UCLA Head and Neck Cancer Program, David Geffen School of Medicine at UCLA, 10833 Le Conte Avenue, Los Angeles, CA 90095 (United States); Clinical and Translational Science Institute, David Geffen School of Medicine at UCLA, 10833 Le Conte Avenue, Los Angeles, CA 90095 (United States)

    2014-05-07

    Cancer, a major health problem, affects 12 million people worldwide every year. With surgery and chemo-radiation the long term survival rate for the majority of cancer patients is dismal. Thus novel treatments are urgently needed. Immunotherapy, the harnessing of the immune system to destroy cancer cells is an attractive option with potential for long term anti-tumor benefit. Cytokines are biological response modifiers that stimulate anti-tumor immune responses. In this review, we discuss the anti-tumor efficacy of the chemotactic cytokine CCL21 and its pre-clinical and clinical application in cancer.

  4. Leukocyte attraction by CCL20 and its receptor CCR6 in humans and mice with pneumococcal meningitis

    NARCIS (Netherlands)

    Klein, Matthias; Brouwer, Matthijs C.; Angele, Barbara; Geldhoff, Madelijn; Marquez, Gabriel; Varona, Rosa; Häcker, Georg; Schmetzer, Helga; Häcker, Hans; Hammerschmidt, Sven; van der Ende, Arie; Pfister, Hans-Walter; van de Beek, Diederik; Koedel, Uwe

    2014-01-01

    We previously identified CCL20 as an early chemokine in the cerebrospinal fluid (CSF) of patients with pneumococcal meningitis but its functional relevance was unknown. Here we studied the role of CCL20 and its receptor CCR6 in pneumococcal meningitis. In a prospective nationwide study, CCL20 levels

  5. InAs/GaAs quantum dots for THz generation

    International Nuclear Information System (INIS)

    Daghestani, N.S.; Cataluna, M.A.; Berry, G.; Rose, M.J.; Ross, G.

    2012-01-01

    We report pulsed terahertz generation from InAs/GaAs quantum-dot based photoconductive devices. For 800 nm optical excitation, the dots act as recombination centres for carriers generated in the GaAs layers. Using photoreflective pump-probe measurements we demonstrate that the photogenerated carrier lifetime decreases when a lateral bias is applied. This can be attributed to an increase in the capture area of the dots when under bias. Two types of antenna metallization were investigated; non-Ohmic, and quasi-Ohmic contacts. Non-Ohmic antennae displayed resilience to Joule heating when operated at a field strength of 46 MV/m. The breakdown field of the devices was 48 MV/m, which is comparable to the breakdown field of bulk GaAs (∝50 MV/m). The maximum estimated infrared-to-THz conversion efficiency is ∝1x10 -5 . (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  6. CCL5 rs2107538 Polymorphism Increased the Risk of Tuberculosis in a Sample of Iranian Population

    Directory of Open Access Journals (Sweden)

    Hamid Reza Kouhpayeh

    2016-01-01

    Full Text Available Cysteine-cysteine chemokine ligand 5 (CCL5 with immunoregulatory and inflammatory activities has an important role in granuloma formations that activates and stimulates T-cells and macrophages. Cysteine-cysteine chemokine receptor 5 (CCR5 is a chemokine receptor, which is important for migration of immune cells to site of infection. In the present study we investigated the possible association between CCL5 –403G/A (rs2107538, CCL5 –28C/G (rs2280788 and CCR5 Δ32 polymorphisms and pulmonary tuberculosis (PTB in an Iranian population. This case-control study was performed on 160 patients with pulmonary tuberculosis and 160 unrelated healthy subjects. The CCL5 –403G/A, CCL5 –28C/G and CCR5 Δ32 polymorphisms were genotyped by allele-specific polymerase chain reaction (AS-PCR, tetra amplification refractory mutation system polymerase chain reaction (T-ARMS PCR and PCR, respectively. Our results showed that GA as well as GA+AA genotypes of CCL5 –403G/A (rs2107538 increased the risk of PTB in comparison with GG genotype (OR=1.70, 95% CI=1.03–2.81, P=0.038 and OR=1.64, 95% CI=1.00–2.68, P=0.049, respectively. No significant association was found between CCL5 –28C/G as well as CCR5 Δ32 polymorphism and PTB risk. In conclusion, our findings proposed that CCL5 –403G>A polymorphism may be a risk factor for susceptibility to PTB in our population. Larger sample sizes with different ethnicities are required to validate our findings.

  7. CCL3L1-CCR5 genotype improves the assessment of AIDS Risk in HIV-1-infected individuals.

    Science.gov (United States)

    Kulkarni, Hemant; Agan, Brian K; Marconi, Vincent C; O'Connell, Robert J; Camargo, Jose F; He, Weijing; Delmar, Judith; Phelps, Kenneth R; Crawford, George; Clark, Robert A; Dolan, Matthew J; Ahuja, Sunil K

    2008-09-08

    Whether vexing clinical decision-making dilemmas can be partly addressed by recent advances in genomics is unclear. For example, when to initiate highly active antiretroviral therapy (HAART) during HIV-1 infection remains a clinical dilemma. This decision relies heavily on assessing AIDS risk based on the CD4+ T cell count and plasma viral load. However, the trajectories of these two laboratory markers are influenced, in part, by polymorphisms in CCR5, the major HIV coreceptor, and the gene copy number of CCL3L1, a potent CCR5 ligand and HIV-suppressive chemokine. Therefore, we determined whether accounting for both genetic and laboratory markers provided an improved means of assessing AIDS risk. In a prospective, single-site, ethnically-mixed cohort of 1,132 HIV-positive subjects, we determined the AIDS risk conveyed by the laboratory and genetic markers separately and in combination. Subjects were assigned to a low, moderate or high genetic risk group (GRG) based on variations in CCL3L1 and CCR5. The predictive value of the CCL3L1-CCR5 GRGs, as estimated by likelihood ratios, was equivalent to that of the laboratory markers. GRG status also predicted AIDS development when the laboratory markers conveyed a contrary risk. Additionally, in two separate and large groups of HIV+ subjects from a natural history cohort, the results from additive risk-scoring systems and classification and regression tree (CART) analysis revealed that the laboratory and CCL3L1-CCR5 genetic markers together provided more prognostic information than either marker alone. Furthermore, GRGs independently predicted the time interval from seroconversion to CD4+ cell count thresholds used to guide HAART initiation. The combination of the laboratory and genetic markers captures a broader spectrum of AIDS risk than either marker alone. By tracking a unique aspect of AIDS risk distinct from that captured by the laboratory parameters, CCL3L1-CCR5 genotypes may have utility in HIV clinical management

  8. CCL11 is increased in the CNS in chronic traumatic encephalopathy but not in Alzheimer's disease.

    Science.gov (United States)

    Cherry, Jonathan D; Stein, Thor D; Tripodis, Yorghos; Alvarez, Victor E; Huber, Bertrand R; Au, Rhoda; Kiernan, Patrick T; Daneshvar, Daniel H; Mez, Jesse; Solomon, Todd M; Alosco, Michael L; McKee, Ann C

    2017-01-01

    CCL11, a protein previously associated with age-associated cognitive decline, is observed to be increased in the brain and cerebrospinal fluid (CSF) in chronic traumatic encephalopathy (CTE) compared to Alzheimer's disease (AD). Using a cohort of 23 deceased American football players with neuropathologically verified CTE, 50 subjects with neuropathologically diagnosed AD, and 18 non-athlete controls, CCL11 was measured with ELISA in the dorsolateral frontal cortex (DLFC) and CSF. CCL11 levels were significantly increased in the DLFC in subjects with CTE (fold change = 1.234, p history of head trauma. This increase was also seen to correlate with years of exposure to American football (β = 0.426, p = 0.048) independent of age (β = -0.046, p = 0.824). Preliminary analyses of a subset of subjects with available post-mortem CSF showed a trend for increased CCL11 among individuals with CTE (p = 0.069) mirroring the increase in the DLFC. Furthermore, an association between CSF CCL11 levels and the number of years exposed to football (β = 0.685, p = 0.040) was observed independent of age (β = -0.103, p = 0.716). Finally, a receiver operating characteristic (ROC) curve analysis demonstrated CSF CCL11 accurately distinguished CTE subjects from non-athlete controls and AD subjects (AUC = 0.839, 95% CI 0.62-1.058, p = 0.028). Overall, the current findings provide preliminary evidence that CCL11 may be a novel target for future CTE biomarker studies.

  9. CC-Chemokine CCL15 Expression and Possible Implications for the Pathogenesis of IgE-Related Severe Asthma

    Directory of Open Access Journals (Sweden)

    Yasuo Shimizu

    2012-01-01

    Full Text Available Airway inflammation is accompanied by infiltration of inflammatory cells and an abnormal response of airway smooth muscle. These cells secrete chemokines and express the cell surface chemokine receptors that play an important role in the migration and degranulation of inflammatory cells. Omalizumab is a monoclonal antibody directed against immunoglobulin E, and its blocking of IgE signaling not only reduces inflammatory cell infiltration mediated by the Th2 immune response but also inhibits other immune responses. The chemokine CCL15 is influenced by omalizumab, and the source of CCL15 has been reported to be airway smooth muscle cells and basophils. CCL15 binds to its receptor CCR1, which has been reported to be expressed by various inflammatory cells and also by airway smooth muscle cells. Therefore, CCL15/CCR1 signaling could be a target for the treatment of asthma. We review the role of CCL15 in the pathogenesis of asthma and also discuss the influence of IgE-mediated immunomodulation via CCL15 and its receptor CCR1.

  10. Up-regulation of the chemokine CCL21 in the skin of subjects exposed to irritants

    Directory of Open Access Journals (Sweden)

    Kuznitzky Raquel

    2004-04-01

    Full Text Available Abstract Background Expression of murine CCL21 by dermal lymphatic endothelial cells (LEC has been demonstrated to be one of the most important steps in Langerhans cell emigration from skin. Previously, our group and others have found that this chemokine is up-regulated in different human inflammatory skin diseases mediated by diverse specific immune responses. This study was carried out to investigate the involvement of CCL21 in human skin after challenge with irritant agents responsible for inducing Irritant Contact Dermatitis (ICD. Results Eleven normal individuals were challenged with different chemical or physical irritants. Two patients with Allergic Contact Dermatitis (ACD were also challenged with the relevant antigen in order to have a positive control for CCL21 expression. Macroscopic as well as microscopic responses were evaluated. We observed typical ICD responses with mostly mononuclear cells in perivascular areas, but a predominance of polymorphonuclear cells away from the inflamed blood vessels and in the epidermis at 24 hours. Immunohistochemical studies showed up-regulation of CCL21 by lymphatic endothelial cells in all the biopsies taken from ICD and ACD lesions compared to normal skin. Kinetic study at 10, 48, 96 and 168 hours after contact with a classical irritant (sodium lauryl sulphate showed that the expression of CCL21 was increased in lymphatic vessels at 10 hours, peaked at 48 hours, and then gradually declined. There was a strong correlation between CCL21 expression and the macroscopic response (r = 0.69; p = 0.0008, but not between CCL21 and the number of infiltrating cells in the lesions. Conclusions These results provide new evidence for the role of CCL21 in inflammatory processes. Since the up-regulation of this chemokine was observed in ICD and ACD, it is tempting to speculate that this mechanism operates independently of the type of dermal insult, facilitating the emigration of CCR7+ cells.

  11. GRUNCLE, 1. Collision Source Calculation for Program DOT. DOT-3.5, 2-D Neutron Transport, Gamma Transport Program DOT with New Space-Scaling

    International Nuclear Information System (INIS)

    1996-01-01

    mesh. Anisotropic scattering is treated using a Legendre expansion of arbitrary order. Convergence can be accelerated by several optional schemes, including a pointwise rescaling technique. DOT-3.5/E: Differs from DOT-3.5 in that exponential supplementary equations, as well as the usual diamond and weighted schemes, may be used to find the mesh-centre flux from the fluxes at the faces of the mesh. The model: 1. always gives positive solutions and does not require any fix-up techniques provided that the source is non-negative; 2. improves convergence rate in most neutron deep-penetration problems and, for any practical spatial discretization, always requires CPU times not only smaller than those required by DOT-3 mixed (linear + step fix-up) model, but also shorter (generally 10-20%) than the times required by DOT-3.5 weighted difference model; 3. increasing spatial mesh size supplies solutions which are always reasonable overestimates of the exact solution and its numerical behaviour is more stable and coherent than the mixed mode. Experience up to now from several deep penetration problems in (r,z) and (x,y) geometry shows that, while for neutrons the exponential model almost always works very well, for gamma rays its behaviour may be critical and in some cases there is lack of convergence. C - Restrictions on the complexity of the problem: The total storage requirement is determined by a formula given in the input description. No other restrictions to problem size are applicable

  12. CCL11 is increased in the CNS in chronic traumatic encephalopathy but not in Alzheimer's disease.

    Directory of Open Access Journals (Sweden)

    Jonathan D Cherry

    Full Text Available CCL11, a protein previously associated with age-associated cognitive decline, is observed to be increased in the brain and cerebrospinal fluid (CSF in chronic traumatic encephalopathy (CTE compared to Alzheimer's disease (AD. Using a cohort of 23 deceased American football players with neuropathologically verified CTE, 50 subjects with neuropathologically diagnosed AD, and 18 non-athlete controls, CCL11 was measured with ELISA in the dorsolateral frontal cortex (DLFC and CSF. CCL11 levels were significantly increased in the DLFC in subjects with CTE (fold change = 1.234, p < 0.050 compared to non-athlete controls and AD subjects with out a history of head trauma. This increase was also seen to correlate with years of exposure to American football (β = 0.426, p = 0.048 independent of age (β = -0.046, p = 0.824. Preliminary analyses of a subset of subjects with available post-mortem CSF showed a trend for increased CCL11 among individuals with CTE (p = 0.069 mirroring the increase in the DLFC. Furthermore, an association between CSF CCL11 levels and the number of years exposed to football (β = 0.685, p = 0.040 was observed independent of age (β = -0.103, p = 0.716. Finally, a receiver operating characteristic (ROC curve analysis demonstrated CSF CCL11 accurately distinguished CTE subjects from non-athlete controls and AD subjects (AUC = 0.839, 95% CI 0.62-1.058, p = 0.028. Overall, the current findings provide preliminary evidence that CCL11 may be a novel target for future CTE biomarker studies.

  13. Chemiluminescence behavior of the carbon dots and the reduced state carbon dots

    Energy Technology Data Exchange (ETDEWEB)

    Teng, Ping [Key Laboratory on Luminescence and Real-Time Analysis, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China); Xie, Jianxin [College of Resources and Environment, Yuxi Normal University, Yuxi, Yunnan 653100 (China); Long, Yijuan; Huang, Xiaoxiao; Zhu, Rui; Wang, Xiliang; Liang, Liping [Key Laboratory on Luminescence and Real-Time Analysis, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China); Huang, Yuming, E-mail: ymhuang@swu.edu.cn [Key Laboratory on Luminescence and Real-Time Analysis, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China); Zheng, Huzhi, E-mail: zhenghz@swu.edu.cn [Key Laboratory on Luminescence and Real-Time Analysis, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China)

    2014-02-15

    Potassium permanganate (KMnO{sub 4}) can react with two different carbon nanoparticles, i.e., carbon dots (CDs) and reduced state carbon dots (r-CDs), in a strong acid medium to generate chemiluminescence (CL). Furthermore, the different CL intensities and CL behaviors due to the different surface groups on these two kinds of carbon nanoparticles were confirmed. CL spectra, fluorescence spectra, UV–vis absorption spectra, and electron paramagnanetic resonance spectra were applied to investigate the CL mechanism. The main reaction pathways were proposed as follows: for the CL reaction between CDs and KMnO{sub 4}, the excited states of CDs (CDs{sup ⁎}) and Mn(II) (Mn(II){sup ⁎}) emerged as KMnO{sub 4} could inject holes into CDs, then, the CDs{sup ⁎} and Mn(II){sup ⁎} acted as luminophors to yield CL; in the r-CDs-KMnO{sub 4} system, r-CDs were oxidized by KMnO{sub 4} directly, and CDs{sup ⁎} and Mn(II){sup ⁎} were produced, at the same time, CL occurred. What is more interesting is that the CL intensity of the r-CD system is stronger than that of the CD system, which confirms that functional groups have strong effect on the CL behavior. It inspired us that new carbon nanoparticles with excellent luminous performance can be designed by tuning their surface groups. -- Highlights: • Carbon dots (CDs) and reduced state carbon dots (r-CDs) can react with potassium permanganate (KMnO{sub 4}) in a strong acid to generate chemiluminescence (CL). • With different surface groups, the CL intensity of r-CDs-KMnO{sub 4} system is different from that of CDs-KMnO{sub 4} system. • The CL mechanisms of the two systems were investigated.

  14. CCL5–Glutamate Cross-Talk in Astrocyte-Neuron Communication in Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Anna Pittaluga

    2017-09-01

    Full Text Available The immune system (IS and the central nervous system (CNS are functionally coupled, and a large number of endogenous molecules (i.e., the chemokines for the IS and the classic neurotransmitters for the CNS are shared in common between the two systems. These interactions are key elements for the elucidation of the pathogenesis of central inflammatory diseases. In recent years, evidence has been provided supporting the role of chemokines as modulators of central neurotransmission. It is the case of the chemokines CCL2 and CXCL12 that control pre- and/or post-synaptically the chemical transmission. This article aims to review the functional cross-talk linking another endogenous pro-inflammatory factor released by glial cells, i.e., the chemokine Regulated upon Activation Normal T-cell Expressed and Secreted (CCL5 and the principal neurotransmitter in CNS (i.e., glutamate in physiological and pathological conditions. In particular, the review discusses preclinical data concerning the role of CCL5 as a modulator of central glutamatergic transmission in healthy and demyelinating disorders. The CCL5-mediated control of glutamate release at chemical synapses could be relevant either to the onset of psychiatric symptoms that often accompany the development of multiple sclerosis (MS, but also it might indirectly give a rationale for the progression of inflammation and demyelination. The impact of disease-modifying therapies for the cure of MS on the endogenous availability of CCL5 in CNS will be also summarized. We apologize in advance for omission in our coverage of the existing literature.

  15. Photoemission Studies of Si Quantum Dots with Ge Core: Dots formation, Intermixing at Si-clad/Ge-core interface and Quantum Confinement Effect

    OpenAIRE

    Yudi Darma

    2008-01-01

    Spherical Si nanocrystallites with Ge core (~20nm in average dot diameter) have been prepared by controlling selective growth conditions of low-pressure chemical vapor deposition (LPCVD) on ultrathin SiO2 using alternately pure SiH4 and 5% GeH4 diluted with He. XPS results confirm the highly selective growth of Ge on the pregrown Si dots and subsequently complete coverage by Si selective growth on Ge/Si dots. Compositional mixing and the crystallinity of Si dots with Ge core as a function of ...

  16. Effects of venom immunotherapy on serum level of CCL5/RANTES in patients with Hymenoptera venom allergy.

    Science.gov (United States)

    Gawlik, Radoslaw; Glück, Joanna; Jawor, Barbara; Rogala, Barbara

    2015-01-01

    Hymenoptera venoms are known to cause life-threatening IgE-mediated anaphylactic reactions in allergic individuals. Venom immunotherapy is a recommended treatment of insect allergy with still the mechanism not being completely understood. We decided to assess the serum CCL5/RANTES level in patients who experienced severe anaphylactic reaction to Hymenoptera venom and to find out changes in the course of immunotherapy. Twenty patients (9 men, 11 women, mean age: 31.91 ± 7.63 years) with history of anaphylactic reaction after insect sting were included into the study. Diagnosis was made according to sIgE and skin tests. All of them were enrolled into rush venom immunotherapy with bee or wasp venom extracts (Pharmalgen, ALK-Abello, Horsholm, Denmark). Serum levels of CCL5/RANTES were measured using a commercially available ELISA kit (R&D Systems, Minneapolis, MN). CCL5/RANTES serum concentration are higher in insect venom allergic patients than in healthy controls (887.5 ± 322.77 versus 387.27 ± 85.11 pg/ml). Serum concentration of CCL5/RANTES in insect venom allergic patient was significantly reduced in the course of allergen immunotherapy already after 6 days of vaccination (887.5 ± 322.77 versus 567.32 ± 92.16 pg/ml). CCL5/RANTES serum doesn't correlate with specific IgE. Chemokine CCL5/RANTES participates in allergic inflammation induced by Hymenoptera venom allergens. Specific immunotherapy reduces chemokine CCL5/RANTES serum level already after initial days of venom immunotherapy.

  17. CCL2/CCL5 secreted by the stroma induce IL-6/PYK2 dependent chemoresistance in ovarian cancer.

    Science.gov (United States)

    Pasquier, Jennifer; Gosset, Marie; Geyl, Caroline; Hoarau-Véchot, Jessica; Chevrot, Audrey; Pocard, Marc; Mirshahi, Massoud; Lis, Raphael; Rafii, Arash; Touboul, Cyril

    2018-02-19

    Minimal residual disease is the main issue of advanced ovarian cancer treatment. According to the literature and previous results, we hypothesized that Mesenchymal Stromal Cells (MSC) could support this minimal residual disease by protecting ovarian cancer cells (OCC) from chemotherapy. In vitro study confirmed that MSC could induce OCC chemoresistance without contact using transwell setting. Further experiments showed that this induced chemoresistance was dependent on IL-6 OCC stimulation. We combined meticulous in vitro profiling and tumor xenograft models to study the role of IL-6 in MSC/OCC intereactions. We demonstrated that Tocilizumab® (anti-IL-6R therapy) in association with chemotherapy significantly reduced the peritoneal carcinosis index (PCI) than chemotherapy alone in mice xenografted with OCCs+MSCs. Further experiments showed that CCL2 and CCL5 are released by MSC in transwell co-culture and induce OCCs IL-6 secretion and chemoresistance. Finally, we found that IL-6 induced chemoresistance was dependent on PYK2 phosphorylation. These findings highlight the potential key role of the stroma in protecting minimal residual disease from chemotherapy, thus favoring recurrences. Future clinical trials targeting stroma could use anti-IL-6 therapy in association with chemotherapy.

  18. CCL5 promotes vascular endothelial growth factor expression and induces angiogenesis by down-regulating miR-199a in human chondrosarcoma cells.

    Science.gov (United States)

    Liu, Guan-Ting; Huang, Yuan-Li; Tzeng, Huey-En; Tsai, Chun-Hao; Wang, Shih-Wei; Tang, Chih-Hsin

    2015-02-28

    Chondrosarcoma is a primary malignant bone cancer, with a potent capacity to invade locally and cause distant metastasis. Angiogenesis is a critical step in tumor growth and metastasis. Chemokine CCL5 (previously called RANTES) has been shown to facilitate tumor progression and metastasis. However, the relationship of CCL5 with vascular endothelial growth factor (VEGF) expression and angiogenesis in human chondrosarcoma is mostly unknown. In this study, CCL5 increased VEGF expression and also promoted chondrosarcoma medium-mediated angiogenesis in vitro as well as angiogenesis effects in the chick chorioallantoic membrane and Matrigel plug nude mice model in vivo. MicroRNA analysis was performed in CCL5-treated chondrosarcoma cells versus control cells to investigate the mechanism of CCL5-mediated promotion of chondrosarcoma angiogenesis. Among the miRNAs regulated by CCL5, miR-199a was the most downregulated miRNA after CCL5 treatment. In addition, co-transfection with miR-199a mimic reversed the CCL5-mediated VEGF expression and angiogenesis in vitro and in vivo. Moreover, overexpression of CCL5 increased tumor-associated angiogenesis and tumor growth by downregulating miR-199a in the xenograft tumor angiogenesis model. Taken together, these results demonstrated that CCL5 promotes VEGF-dependent angiogenesis in human chondrosarcoma cells by downregulating miR-199a. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  19. Targeting chemokine (C-C motif) ligand 2 (CCL2) as an example of translation of cancer molecular biology to the clinic.

    Science.gov (United States)

    Zhang, Jian; Patel, Lalit; Pienta, Kenneth J

    2010-01-01

    Chemokines are a family of small and secreted proteins that play pleiotropic roles in inflammation-related pathological diseases, including cancer. Among the identified 50 human chemokines, chemokine (C-C motif) ligand 2 (CCL2) is of particular importance in cancer development since it serves as one of the key mediators of interactions between tumor and host cells. CCL2 is produced by cancer cells and multiple different host cells within the tumor microenvironment. CCL2 mediates tumorigenesis in many different cancer types. For example, CCL2 has been reported to promote prostate cancer cell proliferation, migration, invasion, and survival, via binding to its functional receptor CCR2. Furthermore, CCL2 induces the recruitment of macrophages and induces angiogenesis and matrix remodeling. Targeting CCL2 has been demonstrated as an effective therapeutic approach in preclinical prostate cancer models, and currently, neutralizing monoclonal antibody against CCL2 has entered into clinical trials in prostate cancer. In this chapter, targeting CCL2 in prostate cancer will be used as an example to show translation of laboratory findings from cancer molecular biology to the clinic. Copyright © 2010 Elsevier Inc. All rights reserved.

  20. Perceptual strategies of pigeons to detect a rotational centre--a hint for star compass learning?

    Directory of Open Access Journals (Sweden)

    Bianca Alert

    Full Text Available Birds can rely on a variety of cues for orientation during migration and homing. Celestial rotation provides the key information for the development of a functioning star and/or sun compass. This celestial compass seems to be the primary reference for calibrating the other orientation systems including the magnetic compass. Thus, detection of the celestial rotational axis is crucial for bird orientation. Here, we use operant conditioning to demonstrate that homing pigeons can principally learn to detect a rotational centre in a rotating dot pattern and we examine their behavioural response strategies in a series of experiments. Initially, most pigeons applied a strategy based on local stimulus information such as movement characteristics of single dots. One pigeon seemed to immediately ignore eccentric stationary dots. After special training, all pigeons could shift their attention to more global cues, which implies that pigeons can learn the concept of a rotational axis. In our experiments, the ability to precisely locate the rotational centre was strongly dependent on the rotational velocity of the dot pattern and it crashed at velocities that were still much faster than natural celestial rotation. We therefore suggest that the axis of the very slow, natural, celestial rotation could be perceived by birds through the movement itself, but that a time-delayed pattern comparison should also be considered as a very likely alternative strategy.

  1. CCL5 promotes VEGF-dependent angiogenesis by down-regulating miR-200b through PI3K/Akt signaling pathway in human chondrosarcoma cells

    Science.gov (United States)

    Liu, Guan-Ting; Chen, Hsien-Te; Tsou, Hsi-Kai; Tan, Tzu-Wei; Fong, Yi-Chin; Chen, Po-Chen; Yang, Wei-Hung; Wang, Shih-Wei; Chen, Jui-Chieh; Tang, Chih-Hsin

    2014-01-01

    Chondrosarcoma is the second most common primary malignant bone cancer, with potential for local invasion and distant metastasis. Chemokine CCL5 (formerly RANTES) of the CC-chemokine family plays a crucial role in metastasis. Angiogenesis is essential for the cancer metastasis. However, correlation of CCL5 with vascular endothelial growth factor (VEGF) expression and angiogenesis in human chondrosarcoma is still unknown. CCL5-mediated VEGF expression was assessed by qPCR, ELISA, and Western blotting. CCL5-induced angiogenesis was examined by migration and tube formation in endothelial progenitor cells in vitro. CCL5 increased VEGF expression and also promoted chondrosarcoma conditional medium-mediated angiogenesis in vitro and in vivo. Stimulation of chondrosarcoma with CCL5 augmented PI3K and Akt phosphorylation, while PI3K and Akt inhibitor or siRNA abolished CCL5-induced VEGF expression and angiogenesis. We also demonstrated CCL5 inhibiting miR-200b expression and miR-200b mimic reversing the CCL5-enhanced VEGF expression and angiogenesis. Moreover, in chondrosarcoma patients showed the positive correlation between CCL5 and VEGF; negative correlation between CCL5 and miR-200b. Taken together, results demonstrate CCL5 promoting VEGF-dependent angiogenesis in human chondrosarcoma cells by down-regulating miR-200b through PI3K/Akt signaling pathway. PMID:25301739

  2. Aspects of the historical development of targetry for heavy ions of 0.05-2000 A centre dot MeV at GSI

    CERN Document Server

    Folger, H

    1999-01-01

    The progressively improved GSI accelerators provide beams of heavy ions from energies of 0.05-2000 A centre dot MeV at high particle intensities now. Therefore, a wide variety of common and new heavy-ion target techniques had to be installed and developed during the past 25 years to prepare and characterize self-supported or backed heavy-ion-targets of chemical elements and compounds from hydrogen (as polyethylene) to uranium. The thickness ranged from 2x10 sup - sup 6 to 20 g/cm sup 2 for beam spots of about 5 mm in diameter. Homogeneity, surface structure or individual shape had to be adapted to the needs of each experiment. Special setups were required for targets of poisonous materials, of highly enriched stable isotopes or those of radioactive species in minute amounts. The capability of thin-layer technologies was as well applied to prepare and measure stripper foils or various high-vacuum deposits for experimental or accelerator purposes. The development of different rotating target wheels and control ...

  3. Randomized study of initial treatment with radiationter dot MCNU or radiationter dot MCNUter dot interferon-. beta. for malignant glioma

    Energy Technology Data Exchange (ETDEWEB)

    Kiya, Katsuzo; Uozumi, Tohru; Kurisu, Kaoru (Hiroshima Univ. (Japan). School of Medicine) (and others)

    1990-02-01

    The efficacy of radiation{center dot}MCNU (MR group) or radiation{center dot}MCNU{center dot}interferon-{beta} (IMR group) for malignant glioma was studied by a randomized trial at numerous medical facilities. MR group was irradiated with 50{approx}60 Gy and intravenously injected with 2 mg/kg of MCNU on the initial day of irradiation and 6 weeks later. IMR group was also given intravenous administration of interferon-{beta} at the dose of 2x10{sup 6}IU/m{sup 2} for 5 serial-days every eight weeks. There was no difference in background between the two groups. The response rate in MR group and IMR group was 44.4% (4/9) and 30.0% (3/10), respectively, showing no significant difference. The resected tumor volume before the start of these regimens seemed to correlate the response to the treatment in both groups. The major toxicity was myelosuppression, especially using MCNU with interferon-{beta}. These results indicated that this combined therapy is effective for malignant glioma, and should be executed further trials and follow up study. (author).

  4. The relationship between nasopharyngeal CCL5 and microbiota on disease severity among infants with bronchiolitis.

    Science.gov (United States)

    Hasegawa, K; Mansbach, J M; Ajami, N J; Petrosino, J F; Freishtat, R J; Teach, S J; Piedra, P A; Camargo, C A

    2017-11-01

    Emerging evidence suggests that the airway microbiota plays an important role in viral bronchiolitis pathobiology. However, little is known about the combined role of airway microbiota and CCL5 in infants with bronchiolitis. In this multicenter prospective cohort study of 1005 infants (age microbiota profiles with regard to the risk of both intensive care use (P interaction =.02) and hospital length-of-stay ≥3 days (P interaction =.03). Among infants with lower CCL5 levels, the Haemophilus-dominant microbiota profile was associated with a higher risk of intensive care use (OR, 3.20; 95%CI, 1.18-8.68; P=.02) and hospital length-of-stay ≥3 days (OR, 4.14; 95%CI, 2.08-8.24; Pmicrobiota profiles and these severity outcomes (all P≥.10). © 2017 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd.

  5. Tumor hypoxia modulates podoplanin/CCL21 interactions in CCR7+ NK cell recruitment and CCR7+ tumor cell mobilization.

    Science.gov (United States)

    Tejchman, Anna; Lamerant-Fayel, Nathalie; Jacquinet, Jean-Claude; Bielawska-Pohl, Aleksandra; Mleczko-Sanecka, Katarzyna; Grillon, Catherine; Chouaib, Salem; Ugorski, Maciej; Kieda, Claudine

    2017-05-09

    Podoplanin (PDPN), an O-glycosylated, transmembrane, mucin-type glycoprotein, is expressed by cancer associated fibroblasts (CAFs). In malignant transformation, PDPN is subjected to changes and its role is yet to be established. Here we show that it is involved in modulating the activity of the CCL21/CCR7 chemokine/receptor axis in a hypoxia-dependent manner. In the present model, breast cancer MDA-MB-231 cells and NKL3 cells express the surface CCR7 receptor for CCL21 chemokine which is a potent chemoattractant able to bind to PDPN. The impact of the CCL21/CCR7 axis in the molecular mechanism of the adhesion of NKL3 cells and of MDA-MB-231 breast cancer cells was reduced in a hypoxic tumor environment. In addition to its known effect on migration, CCL21/CCR7 interaction was shown to allow NK cell adhesion to endothelial cells (ECs) and its reduction by hypoxia. A PDPN expressing model of CAFs made it possible to demonstrate the same CCL21/CCR7 axis involvement in the tumor cells to CAFs recognition mechanism through PDPN binding of CCL21. PDPN was induced by hypoxia and its overexpression undergoes a reduction of adhesion, making it an anti-adhesion molecule in the absence of CCL21, in the tumor. CCL21/CCR7 modulated NK cells/ECs and MDA-MB-231 cells/CAF PDPN-dependent interactions were further shown to be linked to hypoxia-dependent microRNAs as miRs: miR-210 and specifically miR-21, miR-29b which influence PDPN expression.

  6. Elucidating a Key Anti-HIV-1 and Cancer-Associated Axis: The Structure of CCL5 (Rantes) in Complex with CCR5

    Science.gov (United States)

    Tamamis, Phanourios; Floudas, Christodoulos A.

    2014-06-01

    CCL5 (RANTES) is an inflammatory chemokine which binds to chemokine receptor CCR5 and induces signaling. The CCL5:CCR5 associated chemotactic signaling is of critical biological importance and is a potential HIV-1 therapeutic axis. Several studies provided growing evidence for the expression of CCL5 and CCR5 in non-hematological malignancies. Therefore, the delineation of the CCL5:CCR5 complex structure can pave the way for novel CCR5-targeted drugs. We employed a computational protocol which is primarily based on free energy calculations and molecular dynamics simulations, and report, what is to our knowledge, the first computationally derived CCL5:CCR5 complex structure which is in excellent agreement with experimental findings and clarifies the functional role of CCL5 and CCR5 residues which are associated with binding and signaling. A wealth of polar and non-polar interactions contributes to the tight CCL5:CCR5 binding. The structure of an HIV-1 gp120 V3 loop in complex with CCR5 has recently been derived through a similar computational protocol. A comparison between the CCL5 : CCR5 and the HIV-1 gp120 V3 loop : CCR5 complex structures depicts that both the chemokine and the virus primarily interact with the same CCR5 residues. The present work provides insights into the blocking mechanism of HIV-1 by CCL5.

  7. Emerging role of chemokine CC motif ligand 4 related mechanisms in diabetes mellitus and cardiovascular disease: friends or foes?

    Science.gov (United States)

    Chang, Ting-Ting; Chen, Jaw-Wen

    2016-08-24

    Chemokines are critical components in pathology. The roles of chemokine CC motif ligand 4 (CCL4) and its receptor are associated with diabetes mellitus (DM) and atherosclerosis cardiovascular diseases. However, due to the complexity of these diseases, the specific effects of CCL4 remain unclear, although recent reports have suggested that multiple pathways are related to CCL4. In this review, we provide an overview of the role and potential mechanisms of CCL4 and one of its major receptors, fifth CC chemokine receptor (CCR5), in DM and cardiovascular diseases. CCL4-related mechanisms, including CCL4 and CCR5, might provide potential therapeutic targets in DM and/or atherosclerosis cardiovascular diseases.

  8. The porcine skin associated T-cell homing chemokine CCL27: molecular cloning and mRNA expression in piglets infected experimentally with Staphylococcus hyicus

    DEFF Research Database (Denmark)

    Johnsen, C. K.; Jensen, Annette Nygaard; Ahrens, P.

    2003-01-01

    CCL27 (also named CTACK, ALP, ILC and ESkine) is a CC chemokine primarily expressed by keratinocytes of the skin. The cognate receptor of CCL27 named CCR10 (GPR-2), is also expressed in skin-derived cells, and in addition by a subset of peripheral blood T-cells and in a variety of other tissues....... In this paper, we report the cloning of porcine CCL27 cDNA and investigation of CCL27 mRNA expression in Staphylococcus hyicus infected piglets. At the protein level, 77 and 74% homology was found to human and mouse CCL27 sequences, respectively. The results of the expression analyses show that CCL27 m...

  9. Imaging and Manipulating Energy Transfer Among Quantum Dots at Individual Dot Resolution.

    Science.gov (United States)

    Nguyen, Duc; Nguyen, Huy A; Lyding, Joseph W; Gruebele, Martin

    2017-06-27

    Many processes of interest in quantum dots involve charge or energy transfer from one dot to another. Energy transfer in films of quantum dots as well as between linked quantum dots has been demonstrated by luminescence shift, and the ultrafast time-dependence of energy transfer processes has been resolved. Bandgap variation among dots (energy disorder) and dot separation are known to play an important role in how energy diffuses. Thus, it would be very useful if energy transfer could be visualized directly on a dot-by-dot basis among small clusters or within films of quantum dots. To that effect, we report single molecule optical absorption detected by scanning tunneling microscopy (SMA-STM) to image energy pooling from donor into acceptor dots on a dot-by-dot basis. We show that we can manipulate groups of quantum dots by pruning away the dominant acceptor dot, and switching the energy transfer path to a different acceptor dot. Our experimental data agrees well with a simple Monte Carlo lattice model of energy transfer, similar to models in the literature, in which excitation energy is transferred preferentially from dots with a larger bandgap to dots with a smaller bandgap.

  10. Noncanonical Pathway for Regulation of CCL2 Expression by an mTORC1-FOXK1 Axis Promotes Recruitment of Tumor-Associated Macrophages

    Directory of Open Access Journals (Sweden)

    Hirokazu Nakatsumi

    2017-11-01

    Full Text Available C-C chemokine ligand 2 (CCL2 plays pivotal roles in tumor formation, progression, and metastasis. Although CCL2 expression has been found to be dependent on the nuclear factor (NF-κB signaling pathway, the regulation of CCL2 production in tumor cells has remained unclear. We have identified a noncanonical pathway for regulation of CCL2 production that is mediated by mammalian target of rapamycin complex 1 (mTORC1 but independent of NF-κB. Multiple phosphoproteomics approaches identified the transcription factor forkhead box K1 (FOXK1 as a downstream target of mTORC1. Activation of mTORC1 induces dephosphorylation of FOXK1, resulting in transactivation of the CCL2 gene. Inhibition of the mTORC1-FOXK1 axis attenuated insulin-induced CCL2 production as well as the accumulation of tumor-associated monocytes-macrophages and tumor progression in mice. Our results suggest that FOXK1 directly links mTORC1 signaling and CCL2 expression in a manner independent of NF-κB and that CCL2 produced by this pathway contributes to tumor progression.

  11. Bright infrared quantum-dot light-emitting diodes through inter-dot spacing control

    KAUST Repository

    Sun, Liangfeng; Choi, Joshua J.; Stachnik, David; Bartnik, Adam C.; Hyun, Byung-Ryool; Malliaras, George G.; Hanrath, Tobias; Wise, Frank W.

    2012-01-01

    Infrared light-emitting diodes are currently fabricated from direct-gap semiconductors using epitaxy, which makes them expensive and difficult to integrate with other materials. Light-emitting diodes based on colloidal semiconductor quantum dots, on the other hand, can be solution-processed at low cost, and can be directly integrated with silicon. However, so far, exciton dissociation and recombination have not been well controlled in these devices, and this has limited their performance. Here, by tuning the distance between adjacent PbS quantum dots, we fabricate thin-film quantum-dot light-emitting diodes that operate at infrared wavelengths with radiances (6.4 W sr '1 m '2) eight times higher and external quantum efficiencies (2.0%) two times higher than the highest values previously reported. The distance between adjacent dots is tuned over a range of 1.3 nm by varying the lengths of the linker molecules from three to eight CH 2 groups, which allows us to achieve the optimum balance between charge injection and radiative exciton recombination. The electroluminescent powers of the best devices are comparable to those produced by commercial InGaAsP light-emitting diodes. By varying the size of the quantum dots, we can tune the emission wavelengths between 800 and 1,850 nm.© 2012 Macmillan Publishers Limited.

  12. Bright infrared quantum-dot light-emitting diodes through inter-dot spacing control.

    Science.gov (United States)

    Sun, Liangfeng; Choi, Joshua J; Stachnik, David; Bartnik, Adam C; Hyun, Byung-Ryool; Malliaras, George G; Hanrath, Tobias; Wise, Frank W

    2012-05-06

    Infrared light-emitting diodes are currently fabricated from direct-gap semiconductors using epitaxy, which makes them expensive and difficult to integrate with other materials. Light-emitting diodes based on colloidal semiconductor quantum dots, on the other hand, can be solution-processed at low cost, and can be directly integrated with silicon. However, so far, exciton dissociation and recombination have not been well controlled in these devices, and this has limited their performance. Here, by tuning the distance between adjacent PbS quantum dots, we fabricate thin-film quantum-dot light-emitting diodes that operate at infrared wavelengths with radiances (6.4 W sr(-1) m(-2)) eight times higher and external quantum efficiencies (2.0%) two times higher than the highest values previously reported. The distance between adjacent dots is tuned over a range of 1.3 nm by varying the lengths of the linker molecules from three to eight CH(2) groups, which allows us to achieve the optimum balance between charge injection and radiative exciton recombination. The electroluminescent powers of the best devices are comparable to those produced by commercial InGaAsP light-emitting diodes. By varying the size of the quantum dots, we can tune the emission wavelengths between 800 and 1,850 nm.

  13. Bright infrared quantum-dot light-emitting diodes through inter-dot spacing control

    KAUST Repository

    Sun, Liangfeng

    2012-05-06

    Infrared light-emitting diodes are currently fabricated from direct-gap semiconductors using epitaxy, which makes them expensive and difficult to integrate with other materials. Light-emitting diodes based on colloidal semiconductor quantum dots, on the other hand, can be solution-processed at low cost, and can be directly integrated with silicon. However, so far, exciton dissociation and recombination have not been well controlled in these devices, and this has limited their performance. Here, by tuning the distance between adjacent PbS quantum dots, we fabricate thin-film quantum-dot light-emitting diodes that operate at infrared wavelengths with radiances (6.4 W sr \\'1 m \\'2) eight times higher and external quantum efficiencies (2.0%) two times higher than the highest values previously reported. The distance between adjacent dots is tuned over a range of 1.3 nm by varying the lengths of the linker molecules from three to eight CH 2 groups, which allows us to achieve the optimum balance between charge injection and radiative exciton recombination. The electroluminescent powers of the best devices are comparable to those produced by commercial InGaAsP light-emitting diodes. By varying the size of the quantum dots, we can tune the emission wavelengths between 800 and 1,850 nm.© 2012 Macmillan Publishers Limited.

  14. Evaluation of the transforming growth factor-beta activity in normal and dry eye human tears by CCL-185 cell bioassay.

    Science.gov (United States)

    Zheng, Xiaofen; De Paiva, Cintia S; Rao, Kavita; Li, De-Quan; Farley, William J; Stern, Michael; Pflugfelder, Stephen C

    2010-09-01

    To develop a new bioassay method using human lung epithelial cells (CCL-185) to assess activity of transforming growth factor beta (TGF-beta) in human tear fluid from normal subjects and patients with dry eye. Two epithelial cell lines, mink lung cells (CCL-64) and human lung cells (CCL-185), were compared to detect the active form of TGF-beta by BrdU incorporation (quantitation of cell DNA synthesis) and WST assay (metabolic activity of viable cells). The effect of TGF-beta on the growth of CCL-185 cells was observed microscopically. Human tears from normal control subjects and patients with dry eye (DE) with and without Sjögren syndrome were evaluated for TGF-beta concentration by Luminex microbead assay, and TGF-beta activity by the CCL-185 cell growth inhibition bioassay. The metabolic activity of viable CCL-185 cells, measured by WST, was shown to be proportional to the TGF-beta1 concentration (R = 0.919) and confirmed by BrdU assay (R = 0.969). Compared with CCL-185, metabolic activity of viable cells and DNA synthesis, measured by WST and BrdU incorporation assays, were shown to be less proportional to the TGF-beta1 concentration in the CCL-64 line (R = 0.42 and 0.17, respectively). Coincubation with human anti-TGF-beta1 antibody (MAB-240) yielded a dose-dependent inhibition of TGF-beta1 (0.3 ng/mL) activity. CCL-185 cell growth observed microscopically was noted to decrease in response to increasing TGF-beta1 concentrations. Levels of immuodetectable TGF-beta1 and TGF-beta2 were similar in normal and DE tears. TGF-beta bioactivity in DE human tears measured by the CCL-185 cells assay was found to be higher (9777.5 +/- 10481.9 pg/mL) than those in normal controls (4129.3 +/- 1342.9 pg/mL) (P tears and 37.6% TGF-beta in normal tears were found to be biologically active. The CCL-185 cell assay was found to be a suitable tool for assessing TGF-beta activity in human tears. Tear TGF-beta bioactivity increases in DE, particularly in Sjögren syndrome, where

  15. Leaving the street and reconstructing lives: impact of DOTS in empowering homeless people in Tokyo, Japan.

    Science.gov (United States)

    Kawatsu, L; Sato, N; Ngamvithayapong-Yanai, J; Ishikawa, N

    2013-07-01

    Since 2000, the Public Health Centre (PHC) in Shinjuku, an area of Tokyo with one of the largest homeless populations in Japan, has been implementing PHC-based DOTS treatment for homeless tuberculosis (TB) patients, with much epidemiological success. Anecdotal evidence indicates that homeless patients treated under DOTS have experienced various positive changes. However, this experience has not yet been systematically analysed. To explore the changes experienced by homeless TB patients, and to discuss the possible role of PHC-based DOTS treatment in effecting these changes. A qualitative study via in-depth interviews with 18 ex-homeless patients who completed DOTS-based treatment at Shinjuku City PHC. The data were analysed using the interpretive content analysis method. The various changes experienced by the participants were categorised into five sub-categories of empowerment, including improved mental health and interpersonal relationships. Some of these changes were attributable to the participants undergoing PHC-based DOTS, which, by addressing their various emotional needs, helped to trigger patient empowerment. Based on our findings, a model of empowerment using PHC-based DOTS was constructed. PHC-based DOTS not only successfully controlled TB, it also empowered homeless patients by addressing their emotional needs. The interpersonal skills of the nurses played a critical role in this process.

  16. Huperzine A inhibits CCL2 production in experimental autoimmune encephalomyelitis mice and in cultured astrocyte.

    Science.gov (United States)

    Tian, G X; Zhu, X Q; Chen, Y; Wu, G C; Wang, J

    2013-01-01

    The active role of chemokines and inflammatory cytokines in the central nervous system (CNS) during the pathogenesis of experimental autoimmune encephalomyelitis (EAE) has been clearly established. Recent studies from our laboratory reported that Huperzine A (HupA) can attenuate the disease process in EAE by the inhibition of inflammation, demyelination, and axonal injury in the spinal cord as well as encephalomyelitic T-cell proliferation. In this study, the effects of low dose HupA on CCL2, TNF-alpha, IL-6, and IL-1beta expression were evaluated in EAE. The effect of HupA on lipopolysachharide (LPS)-induced inflammatory molecule secretion was investigated in cultured-astrocytes in vitro. In MOG35-55-induced EAE mice, intraperitoneal injections of HupA (0.1 mg/kg•d−1) significantly suppressed the expression of CCL2, IL-6, TNF-alpha, and IL-1beta in the spinal cord. HupA also repressed LPS-induced CCL2 production, but with little influence on pro-inflammatory cytokines in primary cultured astrocytes. The inhibition effect of HupA on CCL2 is PPARgamma-dependent and nicotine receptor-independent. Conditioned culture media from HupA-treated astrocyte decreased PBMC migration in vitro. Collectively, these results suggest that HupA can ameliorate EAE by inhibiting CCL2 production in astrocyte, which may consequently decrease inflammatory cell infiltration in the spinal cord. HupA may have a potential therapeutic value for the treatment of MS and other neuroinflammatory diseases.

  17. Broadleaf Mahonia attenuates granulomatous lobular mastitis-associated inflammation by inhibiting CCL-5 expression in macrophages

    Science.gov (United States)

    Wang, Zhiyu; Wang, Neng; Liu, Xiaoyan; Wang, Qi; Xu, Biao; Liu, Pengxi; Zhu, Huayu; Chen, Jianping; Situ, Honglin; Lin, Yi

    2018-01-01

    Granulomatous lobular mastitis (GLM) is a type of chronic mammary inflammation with unclear etiology. Currently systematic corticosteroids and methitrexate are considered as the main drugs for GLM treatment, but a high toxicity and risk of recurrence greatly limit their application. It is therefore an urgent requirement that safe and efficient natural drugs are found to improve the GLM prognosis. Broadleaf Mahonia (BM) is a traditional Chinese herb that is believed to have anti-inflammatory properties according to ancient records of traditional Chinese medicine. The present study investigated this belief and demonstrated that BM significantly inhibited the expression of interleukin-1β (IL-1β), IL-6, cyclooxygenase-2 and inducible nitric oxide synthase in RAW264.7 cells, but had little influence on the cell viability, cell cycle and apoptosis. Meanwhile, the lipopolysaccharide-induced elevation of reactive oxygen species and nitric oxide was also blocked following BM treatment, accompanied with decreased activity of nuclear factor-κB and MAPK signaling. A cytokine array further validated that BM exhibited significant inhibitory effects on several chemoattractants, including chemokine (C-C motif) ligand (CCL)-2, CCL-3, CCL-5 and secreted tumor necrosis factor receptor 1, among which CCL-5 exhibited the highest inhibition ratio in cell and clinical GLM specimens. Collectively, the results show that BM is a novel effective anti-inflammatory herb in vitro and ex vivo, and that CCL-5 may be closely associated with GLM pathogenesis. PMID:29138800

  18. Investigation of defects in electron-irradiated diamond of the type Ia by positron annihilation

    International Nuclear Information System (INIS)

    Novikov, N.V.; Ositinskaya, T.D.; Mikhalenkov, V.S.; Chernyashevskij, A.V.; Shakhovtsov, V.I.; AN Ukrainskoj SSR, Kiev; AN Ukrainskoj SSR, Kiev

    1997-01-01

    To produce vacancy defects, type Ia diamond was irradiated with 3.5 MeV electrons at doses of 5 centre dot 10 16 , 2 centre dot 10 17 , 4 centre dot 10 17 , and 2 centre dot 10 18 e/cm -2 . After each dose, the specimen was investigated using positron annihilation (ACAR), optical spectroscopy in IR, visible regions, and EPR. From ACAR spectra, the S-parameters were found and positron trapping rates were determined. Their behaviour with increasing irradiation doses shows that, in type Ia diamond along with neutral vacancies V degree, deeper traps of positrons are formed, which are most likely vacancies in the negative charge state V - . Specific trapping rates of the V 0 and V - defects are found to be 1.3 centre dot 10 15 and 3.8 centre dot 10 15 s -1 , respectively; trapping cross sections for these defects are also estimated

  19. Validity of the Worth 4 Dot Test in Patients with Red-Green Color Vision Defect.

    Science.gov (United States)

    Bak, Eunoo; Yang, Hee Kyung; Hwang, Jeong-Min

    2017-05-01

    The Worth four dot test uses red and green glasses for binocular dissociation, and although it has been believed that patients with red-green color vision defects cannot accurately perform the Worth four dot test, this has not been validated. Therefore, the purpose of this study was to demonstrate the validity of the Worth four dot test in patients with congenital red-green color vision defects who have normal or abnormal binocular vision. A retrospective review of medical records was performed on 30 consecutive congenital red-green color vision defect patients who underwent the Worth four dot test. The type of color vision anomaly was determined by the Hardy Rand and Rittler (HRR) pseudoisochromatic plate test, Ishihara color test, anomaloscope, and/or the 100 hue test. All patients underwent a complete ophthalmologic examination. Binocular sensory status was evaluated with the Worth four dot test and Randot stereotest. The results were interpreted according to the presence of strabismus or amblyopia. Among the 30 patients, 24 had normal visual acuity without strabismus nor amblyopia and 6 patients had strabismus and/or amblyopia. The 24 patients without strabismus nor amblyopia all showed binocular fusional responses by seeing four dots of the Worth four dot test. Meanwhile, the six patients with strabismus or amblyopia showed various results of fusion, suppression, and diplopia. Congenital red-green color vision defect patients of different types and variable degree of binocularity could successfully perform the Worth four dot test. They showed reliable results that were in accordance with their estimated binocular sensory status.

  20. CCL3 Enhances Antitumor Immune Priming in the Lymph Node via IFNγ with Dependency on Natural Killer Cells

    Directory of Open Access Journals (Sweden)

    Frederick Allen

    2017-10-01

    Full Text Available Lymph node (LN plays a critical role in tumor cell survival outside of the primary tumor sites and dictates overall clinical response in many tumor types (1, 2. Previously, we and others have demonstrated that CCL3 plays an essential role in orchestrating T cell—antigen-presenting cell (APC encounters in the draining LN following vaccination, and such interactions enhance the magnitude of the memory T cell pool (3–5. In the current study, we investigate the cellular responses in the tumor-draining lymph nodes (TDLNs of a CCL3-secreting CT26 colon tumor (L3TU as compared to wild-type tumor (WTTU during the priming phase of an antitumor response (≤10 days. In comparison to WTTU, inoculation of L3TU resulted in suppressed tumor growth, a phenomenon that is accompanied by altered in vivo inflammatory responses on several fronts. Autologous tumor-derived CCL3 (aCCL3 secretion by L3TU bolstered the recruitment of T- and B-lymphocytes, tissue-migratory CD103+ dendritic cells (DCs, and CD49b+ natural killer (NK cells, resulting in significant increases in the differentiation and activation of multiple Interferon-gamma (IFNγ-producing leukocytes in the TDLN. During this early phase of immune priming, NK cells constitute the major producers of IFNγ in the TDLN. CCL3 also enhances CD8+ T cell proliferation and differentiation by augmenting DC capacity to drive T cell activation in the TDLN. Our results revealed that CCL3-dependent IFNγ production and CCL3-induced DC maturation drive the priming of effective antitumor immunity in the TDLN.

  1. Genetic Polymorphism at CCL5 Is Associated With Protection in Chagas' Heart Disease: Antagonistic Participation of CCR1+ and CCR5+ Cells in Chronic Chagasic Cardiomyopathy.

    Science.gov (United States)

    Batista, Angelica Martins; Alvarado-Arnez, Lucia Elena; Alves, Silvia Marinho; Melo, Gloria; Pereira, Isabela Resende; Ruivo, Leonardo Alexandre de Souza; da Silva, Andrea Alice; Gibaldi, Daniel; da Silva, Thayse do E S Protásio; de Lorena, Virginia Maria Barros; de Melo, Adriene Siqueira; de Araújo Soares, Ana Karine; Barros, Michelle da Silva; Costa, Vláudia Maria Assis; Cardoso, Cynthia C; Pacheco, Antonio G; Carrazzone, Cristina; Oliveira, Wilson; Moraes, Milton Ozório; Lannes-Vieira, Joseli

    2018-01-01

    Chronic cardiomyopathy is the main clinical manifestation of Chagas disease (CD), a disease caused by Trypanosoma cruzi infection. A hallmark of chronic chagasic cardiomyopathy (CCC) is a fibrogenic inflammation mainly composed of CD8 + and CD4 + T cells and macrophages. CC-chemokine ligands and receptors have been proposed to drive cell migration toward the heart tissue of CD patients. Single nucleotide polymorphisms (SNPs) in CC-chemokine ligand and receptor genes may determine protein expression. Herein, we evaluated the association of SNPs in the CC-chemokines CCL2 (rs1024611) and CCL5 (rs2107538, rs2280788) and the CCL5/RANTES receptors CCR1 (rs3181077, rs1491961, rs3136672) and CCR5 (rs1799987) with risk and progression toward CCC. We performed a cross-sectional association study of 406 seropositive patients from endemic areas for CD in the State of Pernambuco, Northeast Brazil. The patients were classified as non-cardiopathic (A, n  = 110) or cardiopathic (mild, B1, n  = 163; severe, C, n  = 133). Serum levels of CCL5 and CCL2/MCP-1 were elevated in CD patients but were neither associated with risk/severity of CCC nor with SNP genotypes. After logistic regression analysis with adjustment for the covariates gender and ethnicity, CCL5 -403 (rs2107538) CT heterozygotes (OR = 0.5, P -value = 0.04) and T carriers (OR = 0.5, P -value = 0.01) were associated with protection against CCC. To gain insight into the participation of the CCL5-CCR5/CCR1 axis in CCC, mice were infected with the Colombian T. cruzi strain. Increased CCL5 concentrations were detected in cardiac tissue. In spleen, frequencies of CCR1 + CD8 + T cells and CD14 + macrophages were decreased, while frequencies of CCR5 + cells were increased. Importantly, CCR1 + CD14 + macrophages were mainly IL-10 + , while CCR5 + cells were mostly TNF + . CCR5-deficient infected mice presented reduced TNF concentrations and injury in heart tissue. Selective blockade of CCR1 (Met

  2. Genetic Polymorphism at CCL5 Is Associated With Protection in Chagas’ Heart Disease: Antagonistic Participation of CCR1+ and CCR5+ Cells in Chronic Chagasic Cardiomyopathy

    Science.gov (United States)

    Batista, Angelica Martins; Alvarado-Arnez, Lucia Elena; Alves, Silvia Marinho; Melo, Gloria; Pereira, Isabela Resende; Ruivo, Leonardo Alexandre de Souza; da Silva, Andrea Alice; Gibaldi, Daniel; da Silva, Thayse do E. S. Protásio; de Lorena, Virginia Maria Barros; de Melo, Adriene Siqueira; de Araújo Soares, Ana Karine; Barros, Michelle da Silva; Costa, Vláudia Maria Assis; Cardoso, Cynthia C.; Pacheco, Antonio G.; Carrazzone, Cristina; Oliveira, Wilson; Moraes, Milton Ozório; Lannes-Vieira, Joseli

    2018-01-01

    Chronic cardiomyopathy is the main clinical manifestation of Chagas disease (CD), a disease caused by Trypanosoma cruzi infection. A hallmark of chronic chagasic cardiomyopathy (CCC) is a fibrogenic inflammation mainly composed of CD8+ and CD4+ T cells and macrophages. CC-chemokine ligands and receptors have been proposed to drive cell migration toward the heart tissue of CD patients. Single nucleotide polymorphisms (SNPs) in CC-chemokine ligand and receptor genes may determine protein expression. Herein, we evaluated the association of SNPs in the CC-chemokines CCL2 (rs1024611) and CCL5 (rs2107538, rs2280788) and the CCL5/RANTES receptors CCR1 (rs3181077, rs1491961, rs3136672) and CCR5 (rs1799987) with risk and progression toward CCC. We performed a cross-sectional association study of 406 seropositive patients from endemic areas for CD in the State of Pernambuco, Northeast Brazil. The patients were classified as non-cardiopathic (A, n = 110) or cardiopathic (mild, B1, n = 163; severe, C, n = 133). Serum levels of CCL5 and CCL2/MCP-1 were elevated in CD patients but were neither associated with risk/severity of CCC nor with SNP genotypes. After logistic regression analysis with adjustment for the covariates gender and ethnicity, CCL5 −403 (rs2107538) CT heterozygotes (OR = 0.5, P-value = 0.04) and T carriers (OR = 0.5, P-value = 0.01) were associated with protection against CCC. To gain insight into the participation of the CCL5–CCR5/CCR1 axis in CCC, mice were infected with the Colombian T. cruzi strain. Increased CCL5 concentrations were detected in cardiac tissue. In spleen, frequencies of CCR1+ CD8+ T cells and CD14+ macrophages were decreased, while frequencies of CCR5+ cells were increased. Importantly, CCR1+CD14+ macrophages were mainly IL-10+, while CCR5+ cells were mostly TNF+. CCR5-deficient infected mice presented reduced TNF concentrations and injury in heart tissue. Selective blockade of CCR1 (Met-RANTES therapy) in

  3. Genetic Polymorphism at CCL5 Is Associated With Protection in Chagas’ Heart Disease: Antagonistic Participation of CCR1+ and CCR5+ Cells in Chronic Chagasic Cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Angelica Martins Batista

    2018-04-01

    Full Text Available Chronic cardiomyopathy is the main clinical manifestation of Chagas disease (CD, a disease caused by Trypanosoma cruzi infection. A hallmark of chronic chagasic cardiomyopathy (CCC is a fibrogenic inflammation mainly composed of CD8+ and CD4+ T cells and macrophages. CC-chemokine ligands and receptors have been proposed to drive cell migration toward the heart tissue of CD patients. Single nucleotide polymorphisms (SNPs in CC-chemokine ligand and receptor genes may determine protein expression. Herein, we evaluated the association of SNPs in the CC-chemokines CCL2 (rs1024611 and CCL5 (rs2107538, rs2280788 and the CCL5/RANTES receptors CCR1 (rs3181077, rs1491961, rs3136672 and CCR5 (rs1799987 with risk and progression toward CCC. We performed a cross-sectional association study of 406 seropositive patients from endemic areas for CD in the State of Pernambuco, Northeast Brazil. The patients were classified as non-cardiopathic (A, n = 110 or cardiopathic (mild, B1, n = 163; severe, C, n = 133. Serum levels of CCL5 and CCL2/MCP-1 were elevated in CD patients but were neither associated with risk/severity of CCC nor with SNP genotypes. After logistic regression analysis with adjustment for the covariates gender and ethnicity, CCL5 −403 (rs2107538 CT heterozygotes (OR = 0.5, P-value = 0.04 and T carriers (OR = 0.5, P-value = 0.01 were associated with protection against CCC. To gain insight into the participation of the CCL5–CCR5/CCR1 axis in CCC, mice were infected with the Colombian T. cruzi strain. Increased CCL5 concentrations were detected in cardiac tissue. In spleen, frequencies of CCR1+ CD8+ T cells and CD14+ macrophages were decreased, while frequencies of CCR5+ cells were increased. Importantly, CCR1+CD14+ macrophages were mainly IL-10+, while CCR5+ cells were mostly TNF+. CCR5-deficient infected mice presented reduced TNF concentrations and injury in heart tissue. Selective blockade of CCR1 (Met-RANTES therapy

  4. Serum amyloid P down-regulates CCL-1 expression, and inhibits ...

    African Journals Online (AJOL)

    Differentially expressed proteins in SAP-Tg and C57BL/6 serum were analyzed, and further determined by enzymelinked immunosorbent assay (ELISA) and ... SAP recombinant protein, ELISA results showed that CCL-1 secretion significantly ...

  5. CdSe/ZnS Quantum Dot-Labeled Lateral Flow Strips for Rapid and Quantitative Detection of Gastric Cancer Carbohydrate Antigen 72-4

    Science.gov (United States)

    Yan, Xinyu; Wang, Kan; Lu, Wenting; Qin, Weijian; Cui, Daxiang; He, Jinghua

    2016-03-01

    Carbohydrate antigen 72-4 (CA72-4) is an important biomarker associated closely with diagnosis and prognosis of early gastric cancer. How to realize quick, sensitive, specific, and quantitative detection of CA72-4 in clinical specimens has become a great requirement. Herein, we reported a CdSe/ZnS quantum dot-labeled lateral flow test strip combined with a charge-coupled device (CCD)-based reader was developed for rapid, sensitive, and quantitative detection of CA72-4. Two mouse monoclonal antibodies (mAbs) against CA72-4 were employed. One of them was coated as a test line, while another mAb was labeled with quantum dots and coated onto conjugate pad. The goat anti-mouse IgG was immobilized as a control line. After sample was added, a sandwich structure was formed with CA72-4 and these two mAbs. The fluorescent signal from quantum dots (QD)-labeled mAb in sandwich structure was related to the amount of detected CA72-4. A CCD-based reader was used to realize quantitative detection of CA72-4. Results showed that developed QD-labeled lateral flow strips to detect CA72-4 biomarker with the sensitivity of 2 IU/mL and 10 min detection time. One hundred sera samples from clinical patients with gastric cancer and healthy people were used to confirm specificity of this strip method; results showed that established strip method own 100 % reproducibility and 100 % specificity compared with Roche electrochemiluminescence assay results. In conclusion, CdSe/ZnS quantum dot-labeled lateral flow strips for detection of CA72-4 could realize rapid, sensitive, and specific detection of clinical samples and could own great potential in clinical translation in near future.

  6. Real-Time 200 Gb/s (4x56.25 Gb/s) PAM-4 Transmission over 80 km SSMF using Quantum-Dot Laser and Silicon Ring-Modulator

    DEFF Research Database (Denmark)

    Eiselt, Nicklas; Griesser, Helmut; Eiselt, Michael

    2017-01-01

    We report real-time 4x56.26-Gb/s DWDM PAM-4 transmission over 80-km SSMF with novel optical transmitter sub-assembly comprising multi-wavelength quantum-dot laser and silicon ring modulators. Pre-FEC BERs below 1E-4 are achieved after 80-km, allowing error-free operation with HD-FEC...

  7. CdTe quantum dots functionalized with 4-amino-2,2,6,6-tetramethylpiperidine-N-oxide as luminescent nanoprobe for the sensitive recognition of bromide ion

    International Nuclear Information System (INIS)

    Adegoke, Oluwasesan; Hosten, Eric; McCleland, Cedric; Nyokong, Tebello

    2012-01-01

    Graphical abstract: A bromide ion-selective modified nanoprobe sensor based on 4-amino-2,2,6,6-tetramethylpiperidine-N-oxide (4AT)-functionalized CdTe quantum dots (QDs-4AT) showed a high selectivity and sensitivity for the determination of bromide ion using fluorescence recovery. Highlights: ► Water soluble CdTe quantum dots interact with tetramethylpiperidine-N-oxide. ► Quantum dots fluorescence is quenched by the radical. ► In the presence of bromide ions the fluorescence is restored. ► The sensor is more selective to bromine ions than other common ions. - Abstract: A novel bromide ion-selective modified nanoprobe sensor based on 4-amino-2,2,6,6-tetramethylpiperidine-N-oxide (4AT)-functionalized CdTe quantum dots (QDs-4AT) has been developed. Fluorescence quenching of the QDs by 4AT was observed. The functionalized QDs-4AT nanoprobe allowed a highly sensitive determination of bromide ion via analyte-induced change in the photoluminescence (fluorescence recovery) of the modified QDs. A detection limit of 0.6 nM of bromide ion was obtained, while the interfering effect of other inorganic cations and anions was investigated to examine the selectivity of the nanoprobe. The linear range was between 0.01 and 0.13 μM. Combined fluorescence lifetime and electron paramagnetic resonance measurements confirmed electron transfer processes between bromide ion and QDs-4AT.

  8. Photoemission Studies of Si Quantum Dots with Ge Core: Dots formation, Intermixing at Si-clad/Ge-core interface and Quantum Confinement Effect

    Directory of Open Access Journals (Sweden)

    Yudi Darma

    2008-03-01

    Full Text Available Spherical Si nanocrystallites with Ge core (~20nm in average dot diameter have been prepared by controlling selective growth conditions of low-pressure chemical vapor deposition (LPCVD on ultrathin SiO2 using alternately pure SiH4 and 5% GeH4 diluted with He. XPS results confirm the highly selective growth of Ge on the pregrown Si dots and subsequently complete coverage by Si selective growth on Ge/Si dots. Compositional mixing and the crystallinity of Si dots with Ge core as a function of annealing temperature in the range of 550-800oC has been evaluated by XPS analysis and confirms the diffusion of Ge atoms from Ge core towards the Si clad accompanied by formation of GeOx at the Si clad surface. The first subband energy at the valence band of Si dot with Ge core has been measured as an energy shift at the top of the valence band density of state using XPS. The systematic shift of the valence band maximum towards higher binding energy with progressive deposition in the dot formation indicate the charging effect of dots and SiO2 layer by photoemission during measurements.

  9. Direct synthesis of aqueous quantum dots through 4,4'-bipyridine-based twin ligand strategy.

    Science.gov (United States)

    Kalita, Mausam; Cingarapu, Sreeram; Roy, Santanu; Park, Seok Chan; Higgins, Daniel; Jankowiak, Ryszard; Chikan, Viktor; Klabunde, Kenneth J; Bossmann, Stefan H

    2012-04-16

    We report a new class of derivatized 4,4'-bipyridinium ligands for use in synthesizing highly fluorescent, extremely stable, water-soluble CdSe and CdTe quantum dots (QDs) for bioconjugation. We employed an evaporation-condensation technique, also known as solvated metal atom dispersion (SMAD), followed by a digestive ripening procedure. This method has been used to synthesize both metal nanoparticles and semiconductors in the gram scale with several stabilizing ligands in various solvents. The SMAD technique comprised evaporation condensation and stabilization of CdSe or CdTe in tetrahydrofuran. The as-prepared product was then digestively ripened in both water and dimethyl formamide, leading to narrowing of the particle size distributions. The ligands were synthesized by nucleophilic substitution (S(N)2) reactions using 4,4'-bipyridine as a nucleophile. Confocal microscopy images revealed the orange color of the nanocrystalline QDs with diameters of ~5 nm. The size has been confirmed by using transmission electron microscopy. As a part of our strategy, 85% of the 4,4'-bipyridinium salt was synthesized as propionic acid derivative and used to both stabilize the QDs in water and label basic amino acids and different biomarkers utilizing the carboxylic acid functional group. Fifteen percent of the 4,4'-bipyridinium salt was synthesized as N-propyl maleimide and used as a second ligand to label any protein containing the amino acid cysteine by means of a 1,4-Michael addition. © 2012 American Chemical Society

  10. 15 CFR 738.2 - Commerce Control List (CCL) structure.

    Science.gov (United States)

    2010-01-01

    ... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Commerce Control List (CCL) structure. 738.2 Section 738.2 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued) BUREAU OF INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE EXPORT ADMINISTRATION REGULATIONS...

  11. Increased CCL24/eotaxin-2 with postnatal ozone exposure in allergen-sensitized infant monkeys is not associated with recruitment of eosinophils to airway mucosa

    International Nuclear Information System (INIS)

    Chou, Debbie L.; Gerriets, Joan E.; Schelegle, Edward S.; Hyde, Dallas M.; Miller, Lisa A.

    2011-01-01

    Epidemiology supports a causal link between air pollutant exposure and childhood asthma, but the mechanisms are unknown. We have previously reported that ozone exposure can alter the anatomic distribution of CD25+ lymphocytes in airways of allergen-sensitized infant rhesus monkeys. Here, we hypothesized that ozone may also affect eosinophil trafficking to allergen-sensitized infant airways. To test this hypothesis, we measured blood, lavage, and airway mucosa eosinophils in 3-month old monkeys following cyclical ozone and house dust mite (HDM) aerosol exposures. We also determined if eotaxin family members (CCL11, CCL24, CCL26) are associated with eosinophil location in response to exposures. In lavage, eosinophil numbers increased in animals exposed to ozone and/or HDM. Ozone + HDM animals showed significantly increased CCL24 and CCL26 protein in lavage, but the concentration of CCL11, CCL24, and CCL26 was independent of eosinophil number for all exposure groups. In airway mucosa, eosinophils increased with exposure to HDM alone; comparatively, ozone and ozone + HDM resulted in reduced eosinophils. CCL26 mRNA and immunofluorescence staining increased in airway mucosa of HDM alone animals and correlated with eosinophil volume. In ozone + HDM animal groups, CCL24 mRNA and immunofluorescence increased along with CCR3 mRNA, but did not correlate with airway mucosa eosinophils. Cumulatively, our data indicate that ozone exposure results in a profile of airway eosinophil migration that is distinct from HDM mediated pathways. CCL24 was found to be induced only by combined ozone and HDM exposure, however expression was not associated with the presence of eosinophils within the airway mucosa. -- Highlights: ► Ozone can modulate the localization of eosinophils in infant allergic airways. ► Expression of eotaxins within the lung is affected by ozone and allergen exposure. ► CCL24 induction by ozone and allergen exposure is not linked to eosinophilia.

  12. CCL20 and Beta-Defensin 2 Production by Human Lung Epithelial Cells and Macrophages in Response to Brucella abortus Infection

    Science.gov (United States)

    Fernández, Andrea G.; Bonetto, Josefina; Giambartolomei, Guillermo H.; Fossati, Carlos A.; Baldi, Pablo C.

    2015-01-01

    Both CCL20 and human β-defensin 2 (hBD2) interact with the same membrane receptor and display chemotactic and antimicrobial activities. They are produced by airway epithelia in response to infectious agents and proinflammatory cytokines. Whereas Brucella spp. can infect humans through inhalation, their ability to induce CCL20 and hBD2 in lung cells is unknown. Here we show that B. abortus induces CCL20 expression in human alveolar (A549) or bronchial (Calu-6) epithelial cell lines, primary alveolar epithelial cells, primary human monocytes, monocyte-derived macrophages and the monocytic cell line THP-1. CCL20 expression was mainly mediated by JNK1/2 and NF-kB in both Calu-6 and THP-1 cells. CCL20 secretion was markedly induced in A549, Calu-6 and THP-1 cells by heat-killed B. abortus or a model Brucella lipoprotein (L-Omp19) but not by the B. abortus lipopolysaccharide (LPS). Accordingly, CCL20 production by B. abortus-infected cells was strongly TLR2-dependent. Whereas hBD2 expression was not induced by B. abortus infection, it was significantly induced in A549 cells by conditioned media from B. abortus-infected THP-1 monocytes (CMB). A similar inducing effect was observed on CCL20 secretion. Experiments using blocking agents revealed that IL-1β, but not TNF-α, was involved in the induction of hBD2 and CCL20 secretion by CMB. In the in vitro antimicrobial assay, the lethal dose (LD) 50 of CCL20 for B. abortus (>50 μg/ml) was markedly higher than that against E. coli (1.5 μg/ml) or a B. abortus mutant lacking the O polysaccharide in its LPS (8.7 ug/ml). hBD2 did not kill any of the B. abortus strains at the tested concentrations. These results show that human lung epithelial cells secrete CCL20 and hBD2 in response to B. abortus and/or to cytokines produced by infected monocytes. Whereas these molecules do not seem to exert antimicrobial activity against this pathogen, they could recruit immune cells to the infection site. PMID:26448160

  13. SU(4) Kondo effect in double quantum dots with ferromagnetic leads

    Science.gov (United States)

    Weymann, Ireneusz; Chirla, Razvan; Trocha, Piotr; Moca, Cǎtǎlin Paşcu

    2018-02-01

    We investigate the spin-resolved transport properties, such as the linear conductance and the tunnel magnetoresistance, of a double quantum dot device attached to ferromagnetic leads and look for signatures of the SU (4 ) symmetry in the Kondo regime. We show that the transport behavior greatly depends on the magnetic configuration of the device, and the spin-SU(2) as well as the orbital and spin-SU(4) Kondo effects become generally suppressed when the magnetic configuration of the leads varies from the antiparallel to the parallel one. Furthermore, a finite spin polarization of the leads lifts the spin degeneracy and drives the system from the SU(4) to an orbital-SU(2) Kondo state. We analyze in detail the crossover and show that the Kondo temperature between the two fixed points has a nonmonotonic dependence on the degree of spin polarization of the leads. In terms of methods used, we characterize transport by using a combination of analytical and numerical renormalization group approaches.

  14. Electronic transport through a quantum dot chain with strong dot-lead coupling

    International Nuclear Information System (INIS)

    Liu, Yu; Zheng, Yisong; Gong, Weijiang; Gao, Wenzhu; Lue, Tianquan

    2007-01-01

    By means of the non-equilibrium Green function technique, the electronic transport through an N-quantum-dot chain is theoretically studied. By calculating the linear conductance spectrum and the local density of states in quantum dots, we find the resonant peaks in the spectra coincides with the eigen-energies of the N-quantum-dot chain when the dot-lead coupling is relatively weak. With the increase of the dot-lead coupling, such a correspondence becomes inaccurate. When the dot-lead coupling exceeds twice the interdot coupling, such a mapping collapses completely. The linear conductance turn to reflect the eigen-energies of the (N-2)- or (N-1)-quantum dot chain instead. The two peripheral quantum dots do not manifest themselves in the linear conductance spectrum. More interestingly, with the further increase of the dot-lead coupling, the system behaves just like an (N-2)- or (N-1)-quantum dot chain in weak dot-lead coupling limit, since the resonant peaks becomes narrower with the increase of dot-lead coupling

  15. Printer model for dot-on-dot halftone screens

    Science.gov (United States)

    Balasubramanian, Raja

    1995-04-01

    A printer model is described for dot-on-dot halftone screens. For a given input CMYK signal, the model predicts the resulting spectral reflectance of the printed patch. The model is derived in two steps. First, the C, M, Y, K dot growth functions are determined which relate the input digital value to the actual dot area coverages of the colorants. Next, the reflectance of a patch is predicted as a weighted combination of the reflectances of the four solid C, M, Y, K patches and their various overlays. This approach is analogous to the Neugebauer model, with the random mixing equations being replaced by dot-on-dot mixing equations. A Yule-Neilsen correction factor is incorporated to account for light scattering within the paper. The dot area functions and Yule-Neilsen parameter are chosen to optimize the fit to a set of training data. The model is also extended to a cellular framework, requiring additional measurements. The model is tested with a four color xerographic printer employing a line-on-line halftone screen. CIE L*a*b* errors are obtained between measurements and model predictions. The Yule-Neilsen factor significantly decreases the model error. Accuracy is also increased with the use of a cellular framework.

  16. The anti-inflammatory effect of low-dose radiation therapy involves a diminished CCL20 chemokine expression and granulocyte/endothelial cell adhesion

    Energy Technology Data Exchange (ETDEWEB)

    Roedel, F. [Dept. of Radiotherapy and Oncology, Univ. of Frankfurt/Main (Germany); Hofmann, D.; Auer, J.; Roellinghoff, M.; Beuscher, H.U. [Inst. of Microbiology and Immunology, Univ. of Erlangen-Nuremberg, Erlangen (Germany); Keilholz, L. [Dept. of Radiotherapy, Clinical Center Bayreuth (Germany); Sauer, R. [Dept. of Radiooncology, Univ. of Erlangen-Nuremberg, Erlangen (Germany)

    2008-01-15

    Background and purpose: low-dose radiotherapy (LD-RT) is known to exert an anti-inflammatory effect, however, the underlying molecular mechanisms are not fully understood. The manipulation of polymorphonuclear neutrophil (PMN) function and/or recruitment may be one mechanism. Chemokines contribute to this process by creating a chemotactic gradient and by activating integrins. This study aimed to characterize the effect of LD-RT on CCL20 chemokine production and PMN/endothelial cell (EC) adhesion. Material and methods: the EC line EA.hy.926 was irradiated with doses ranging from 0 to 3 Gy and was co-cultured with PMNs from healthy donors either by direct cell contact or separated by transwell membrane chambers. CXCL8, CCL18, CCL20 chemokine and tumor necrosis factor-(TNF-){alpha} cytokine levels in supernatants were determined by ELISA and adhesion assays were performed. The functional impact of the cytokines transforming growth factor-(TGF-){beta}{sub 1} and TNF-{alpha} and of the intercellular adhesion molecule-(ICAM-)1 on CCL20 expression was analyzed by using neutralizing antibodies. Results: as compared to CXCL8 and CCL18, CCL20 chemokine secretion was found to be exclusively induced by a direct cell-cell contact between PMNs and EA.hy.926 ECs in a TNF-{alpha}-dependent, but ICAM-1-independent manner. Furthermore, irradiation with doses between 0.5 and 1 Gy resulted in a significant reduction of CCL20 release which was dependent on TGF-{beta}{sub 1} (p < 0.01). The decrease of CCL20 paralleled with a significant reduction in PMN/EA.hy.926 EC adhesion (p < 0.001). Conclusion: the modulation of CCL20 chemokine expression and PMN/EC adhesion adds a further facet to the plethora of mechanisms contributing to the anti-inflammatory efficacy of LD-RT. (orig.)

  17. The quantum mechanical description of the dot-dot interaction in ionic colloids

    International Nuclear Information System (INIS)

    Morais, P.C.; Qu, Fanyao

    2007-01-01

    In this study the dot-dot interaction in ionic colloids is systematically investigated by self-consistently solving the coupled Schroedinger and Poisson equations in the frame of finite difference method (FDM). In a first approximation the interacting two-dot system (dimer) is described using the picture of two coupled quantum wells. It was found that the dot-dot interaction changes the colloid characteristic by changing the hopping coefficient (t) and consequently the nanodot surface charge density (σ). The hopping coefficient and the surface charge density were investigated as a function of the dot size and dot-dot distance

  18. Elevated plasma chemokine CCL18/PARC in beta-thalassemia

    NARCIS (Netherlands)

    Dimitriou, E.; Verhoek, M.; Altun, S.; Karabatsos, F.; Moraitou, M.; Youssef, J.; Boot, R.; Sarafidou, J.; Karagiorga, M.; Aerts, H.; Michelakakis, H.

    2005-01-01

    Plasma CCL18/PARC, a member of the CC chemokine family, has been found to be several ten-fold increased in symptomatic Gaucher type I patients. Elevated plasma chitotriosidase levels are a well-known abnormality in Gaucher patients, however, its diagnostic use is limited by the frequent genetic

  19. Ovarian cancer stem-like cells differentiate into endothelial cells and participate in tumor angiogenesis through autocrine CCL5 signaling.

    Science.gov (United States)

    Tang, Shu; Xiang, Tong; Huang, Shuo; Zhou, Jie; Wang, Zhongyu; Xie, Rongkai; Long, Haixia; Zhu, Bo

    2016-06-28

    Cancer stem cells (CSCs) are well known for their self-regeneration and tumorigenesis potential. In addition, the multi-differentiation potential of CSCs has become a popular issue and continues to attract increased research attention. Recent studies demonstrated that CSCs are able to differentiate into functional endothelial cells and participate in tumor angiogenesis. In this study, we found that ovarian cancer stem-like cells (CSLCs) activate the NF-κB and STAT3 signal pathways through autocrine CCL5 signaling and mediate their own differentiation into endothelial cells (ECs). Our data demonstrate that CSLCs differentiate into ECs morphologically and functionally. Anti-CCL5 antibodies and CCL5-shRNA lead to markedly inhibit EC differentiation and the tube formation of CSLCs, both in vitro and in vivo. Recombinant human-CCL5 significantly promotes ovarian CSLCs that differentiate into ECs and form microtube network. The CCL5-mediated EC differentiation of CSLCs depends on binding to receptors, such as CCR1, CCR3, and CCR5. The results demonstrated that CCL5-CCR1/CCR3/CCR5 activates the NF-κB and STAT3 signal pathways, subsequently mediating the differentiation of CSLCs into ECs. Therefore, this study was conducted based on the theory that CSCs improve tumor angiogenesis and provides a novel strategy for anti-angiogenesis in ovarian cancer. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  20. CdTe quantum dots functionalized with 4-amino-2,2,6,6-tetramethylpiperidine-N-oxide as luminescent nanoprobe for the sensitive recognition of bromide ion

    Energy Technology Data Exchange (ETDEWEB)

    Adegoke, Oluwasesan [Department of Chemistry, Rhodes University, Grahamstown 6140 (South Africa); Hosten, Eric; McCleland, Cedric [Department of Chemistry, Nelson Mandela Metropolitan University (South Campus), Port Elizabeth 6031 (South Africa); Nyokong, Tebello, E-mail: t.nyokong@ru.ac.za [Department of Chemistry, Rhodes University, Grahamstown 6140 (South Africa)

    2012-04-06

    Graphical abstract: A bromide ion-selective modified nanoprobe sensor based on 4-amino-2,2,6,6-tetramethylpiperidine-N-oxide (4AT)-functionalized CdTe quantum dots (QDs-4AT) showed a high selectivity and sensitivity for the determination of bromide ion using fluorescence recovery. Highlights: Black-Right-Pointing-Pointer Water soluble CdTe quantum dots interact with tetramethylpiperidine-N-oxide. Black-Right-Pointing-Pointer Quantum dots fluorescence is quenched by the radical. Black-Right-Pointing-Pointer In the presence of bromide ions the fluorescence is restored. Black-Right-Pointing-Pointer The sensor is more selective to bromine ions than other common ions. - Abstract: A novel bromide ion-selective modified nanoprobe sensor based on 4-amino-2,2,6,6-tetramethylpiperidine-N-oxide (4AT)-functionalized CdTe quantum dots (QDs-4AT) has been developed. Fluorescence quenching of the QDs by 4AT was observed. The functionalized QDs-4AT nanoprobe allowed a highly sensitive determination of bromide ion via analyte-induced change in the photoluminescence (fluorescence recovery) of the modified QDs. A detection limit of 0.6 nM of bromide ion was obtained, while the interfering effect of other inorganic cations and anions was investigated to examine the selectivity of the nanoprobe. The linear range was between 0.01 and 0.13 {mu}M. Combined fluorescence lifetime and electron paramagnetic resonance measurements confirmed electron transfer processes between bromide ion and QDs-4AT.

  1. Quantum dots

    International Nuclear Information System (INIS)

    Kouwenhoven, L.; Marcus, C.

    1998-01-01

    Quantum dots are man-made ''droplets'' of charge that can contain anything from a single electron to a collection of several thousand. Their typical dimensions range from nanometres to a few microns, and their size, shape and interactions can be precisely controlled through the use of advanced nanofabrication technology. The physics of quantum dots shows many parallels with the behaviour of naturally occurring quantum systems in atomic and nuclear physics. Indeed, quantum dots exemplify an important trend in condensed-matter physics in which researchers study man-made objects rather than real atoms or nuclei. As in an atom, the energy levels in a quantum dot become quantized due to the confinement of electrons. With quantum dots, however, an experimentalist can scan through the entire periodic table by simply changing a voltage. In this article the authors describe how quantum dots make it possible to explore new physics in regimes that cannot otherwise be accessed in the laboratory. (UK)

  2. CCL19/CCR7 contributes to the pathogenesis of endometriosis via PI3K/Akt pathway by regulating the proliferation and invasion of ESCs.

    Science.gov (United States)

    Diao, Ruiying; Wei, Weixia; Zhao, Jinghui; Tian, Fuying; Cai, Xueyong; Duan, Yong-Gang

    2017-11-01

    The level of CCL19 increased in the peritoneal fluid of women with endometriosis, but the precise mechanism of CCL19/CCR7 in the pathogenesis of endometriosis remains unknown. ELISA and immunohistochemistry were performed to analyze CCL19/CCR7 expressions in peritoneal fluid and endometrium from women with endometriosis (n = 38) and controls (n = 32). Cell proliferation and transwell invasion assays were applied to detect proliferation and invasion of human endometrial stromal cells (ESCs). Expressions of Bcl2, MMP2, MMP9, and p-AKT/AKT were analyzed by Western blot. Peritoneal fluid concentration of CCL19 in patients with endometriosis was higher than that in controls. Those patients with moderate/severe endometriosis had significantly higher peritoneal fluid concentrations of CCL19 compared to those with minimal/mild endometriosis. Higher CCL19 and CCR7 were found in the endometrium with endometriosis compared to control. CCL19 significantly enhanced ESC proliferation and invasion through CCR7 via activating PI3K/Akt signal pathways. CCL19/CCR7 interaction significantly enhanced phosphorylation of Akt, Bcl2, MMP2, and MMP9 in ESCs. These data indicate CCL19/CCR7 contributes to proliferation and invasion of ESCs, which are conducive to the pathogenesis of endometriosis through activating PI3K/Akt pathway. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Blood expression levels of chemokine receptor CCR3 and chemokine CCL11 in age-related macular degeneration

    DEFF Research Database (Denmark)

    Falk, Mads Krüger; Singh, Amardeep; Faber, Carsten

    2014-01-01

    Dysregulation of the CCR3/CCL11 pathway has been implicated in the pathogenesis of choroidal neovascularisation, a common feature of late age-related macular degeneration (AMD). The aim of this study was to investigate the expression of CCR3 and its ligand CCL11 in peripheral blood in patients...

  4. Increased CCL24/eotaxin-2 with postnatal ozone exposure in allergen-sensitized infant monkeys is not associated with recruitment of eosinophils to airway mucosa

    Energy Technology Data Exchange (ETDEWEB)

    Chou, Debbie L.; Gerriets, Joan E. [California National Primate Research Center, UC Davis, Davis, CA 95616 (United States); Schelegle, Edward S.; Hyde, Dallas M. [California National Primate Research Center, UC Davis, Davis, CA 95616 (United States); Department of Anatomy, Physiology, and Cell Biology, UC Davis School of Veterinary Medicine, Davis, CA 95616 (United States); Miller, Lisa A., E-mail: lmiller@ucdavis.edu [California National Primate Research Center, UC Davis, Davis, CA 95616 (United States); Department of Anatomy, Physiology, and Cell Biology, UC Davis School of Veterinary Medicine, Davis, CA 95616 (United States)

    2011-12-15

    Epidemiology supports a causal link between air pollutant exposure and childhood asthma, but the mechanisms are unknown. We have previously reported that ozone exposure can alter the anatomic distribution of CD25+ lymphocytes in airways of allergen-sensitized infant rhesus monkeys. Here, we hypothesized that ozone may also affect eosinophil trafficking to allergen-sensitized infant airways. To test this hypothesis, we measured blood, lavage, and airway mucosa eosinophils in 3-month old monkeys following cyclical ozone and house dust mite (HDM) aerosol exposures. We also determined if eotaxin family members (CCL11, CCL24, CCL26) are associated with eosinophil location in response to exposures. In lavage, eosinophil numbers increased in animals exposed to ozone and/or HDM. Ozone + HDM animals showed significantly increased CCL24 and CCL26 protein in lavage, but the concentration of CCL11, CCL24, and CCL26 was independent of eosinophil number for all exposure groups. In airway mucosa, eosinophils increased with exposure to HDM alone; comparatively, ozone and ozone + HDM resulted in reduced eosinophils. CCL26 mRNA and immunofluorescence staining increased in airway mucosa of HDM alone animals and correlated with eosinophil volume. In ozone + HDM animal groups, CCL24 mRNA and immunofluorescence increased along with CCR3 mRNA, but did not correlate with airway mucosa eosinophils. Cumulatively, our data indicate that ozone exposure results in a profile of airway eosinophil migration that is distinct from HDM mediated pathways. CCL24 was found to be induced only by combined ozone and HDM exposure, however expression was not associated with the presence of eosinophils within the airway mucosa. -- Highlights: Black-Right-Pointing-Pointer Ozone can modulate the localization of eosinophils in infant allergic airways. Black-Right-Pointing-Pointer Expression of eotaxins within the lung is affected by ozone and allergen exposure. Black-Right-Pointing-Pointer CCL24 induction by

  5. Increase of (CdSe/ZnS)Cys quantum dot luminescence intensity in the presence of TPPS4 porphyrin

    International Nuclear Information System (INIS)

    Parra, Gustavo G.; Borissevitch, Iouri E.; Oleinikov, Vladimir A.

    2012-01-01

    Full text: Nanocrystal semiconductor particles or Quantum Dots (QD) possess extraordinary photophysical characteristics, such as extreme high fluorescence quantum yield and optical absorption and very narrow fluorescence band, which can be easily shifted by changing of QD particle size. Due to these characteristics, QD is promising for fluorescence cancer diagnostics and photodynamic treatment. The efficiency of these processes can be in- creased by energy transfer between QD and classic fluorescence probes and photosensitizers (PS). In this work we present on the study of the increase of (CdSe/ZnS)Cys quantum dot luminescence intensity, stimulated by interaction with TPPS 4 porphyrin. The optical absorption and steady-state and time-resolved fluorescence techniques were employed. Water soluble QD (CdSe/ZnS) with emission at 580 nm, functionalized with cysteine (Cys), were studied. TPPS 4 porphyrin was used as a stimulator of QD luminescence. All experiments were realized in PBS buffer (pH 7.3; 7.5 mM) in Milli-Q quality water. The TPPS 4 adding into the QD solutions until the 5μM concentration produced an increase in QD luminescence intensity and lifetime, while for TPPS 4 concentrations higher than 20μM the reduction of the fluorescence intensity was observed, the emission spectra and fluorescence decays profile being unchanged. This effect can not be due to the electrostatic interaction between (CdSe/ZnS)Cys and TPPS 4 because both, (CdSe/ZnS)Cys and TPPS 4 , are negatively charged. We suppose that TPPS 4 porphyrin interacts directly with QD (ZnS) shell, reducing the dangling bound number. This reduction decreases, in turn, the probability of nonradiative ways of the excitation energy dissipation. When the majority of dangling bound is occupied by the TPPS 4 molecules, the effect of QD luminescence reduction (quenching) by porphyrin predominates, probably, via the energy transfer from QD to TPPS 4 . However, because of complexity in the systems involving

  6. Development of operational models of receptor activation including constitutive receptor activity and their use to determine the efficacy of the chemokine CCL17 at the CC chemokine receptor CCR4.

    Science.gov (United States)

    Slack, R J; Hall, D A

    2012-07-01

    BACKGROUND AND PURPOSE The operational model provides a key conceptual framework for the analysis of pharmacological data. However, this model does not include constitutive receptor activity, a frequent phenomenon in modern pharmacology, particularly in recombinant systems. Here, we developed extensions of the operational model which include constitutive activity and applied them to effects of agonists at the chemokine receptor CCR4. EXPERIMENTAL APPROACH The effects of agonists of CCR4 on [(35) S]GTPγS binding to recombinant cell membranes and on the filamentous (F-) actin content of human CD4(+) CCR4(+) T cells were determined. The basal [(35) S]GTPγS binding was changed by varying the GDP concentration whilst the basal F-actin contents of the higher expressing T cell populations were elevated, suggesting constitutive activity of CCR4. Both sets of data were analysed using the mathematical models. RESULTS The affinity of CCL17 (also known as TARC) derived from analysis of the T cell data (pK(a) = 9.61 ± 0.17) was consistent with radioligand binding experiments (9.50 ± 0.11) while that from the [(35) S]GTPγS binding experiments was lower (8.27 ± 0.09). Its intrinsic efficacy differed between the two systems (110 in T cells vs. 11). CONCLUSIONS AND IMPLICATIONS The presence of constitutive receptor activity allows the absolute intrinsic efficacy of agonists to be determined without a contribution from the signal transduction system. Intrinsic efficacy estimated in this way is consistent with Furchgott's definition of this property. CCL17 may have a higher intrinsic efficacy at CCR4 in human T cells than that expressed recombinantly in CHO cells. © 2012 GSK Services Unlimited. British Journal of Pharmacology © 2012 The British Pharmacological Society.

  7. Record Charge Carrier Diffusion Length in Colloidal Quantum Dot Solids via Mutual Dot-To-Dot Surface Passivation.

    Science.gov (United States)

    Carey, Graham H; Levina, Larissa; Comin, Riccardo; Voznyy, Oleksandr; Sargent, Edward H

    2015-06-03

    Through a combination of chemical and mutual dot-to-dot surface passivation, high-quality colloidal quantum dot solids are fabricated. The joint passivation techniques lead to a record diffusion length for colloidal quantum dots of 230 ± 20 nm. The technique is applied to create thick photovoltaic devices that exhibit high current density without losing fill factor. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Age-related differences in anxiety-like behavior and amygdalar CCL2 responsiveness to stress following alcohol withdrawal in male Wistar rats.

    Science.gov (United States)

    Harper, Kathryn M; Knapp, Darin J; Park, Meredith A; Breese, George R

    2017-01-01

    Behavioral and neuroimmune vulnerability to withdrawal from chronic alcohol varies with age. The relation of anxiety-like behavior to amygdalar CCL2 responses following stress after withdrawal from chronic intermittent alcohol (CIA) was investigated in adolescent and adult rats. Adolescent and adult Wistar rats were exposed to CIA (three 5-day blocks of dietary alcohol separated by 2 days of withdrawal) at concentrations that created similar blood alcohol levels across age. Twenty-four hours into the final withdrawal, half of the rats were exposed to 1 h of restraint stress. Four hours post-stress, rats were used for behavior or tissue assays. Anxiety-like behavior was increased versus controls by CIA in adolescents and by CIA + stress in adults. CCL2 mRNA was increased versus controls by CIA in adolescents and by CIA and CIA + stress in adults. CCL2 co-localization with neuronal marker NeuN was decreased versus controls by CIA in adolescents and by CIA + stress in adults. CCL2 co-localization with astrocytic marker GFAP was decreased versus controls by CIA and CIA + stress in adolescents, but experimental groups did not differ from controls in adults. CCL2 co-localization with microglial marker Iba1 was decreased versus controls by stress alone in adolescents and by CIA + stress in adults. Changes in CCL2 protein might control behavior at either age but are particularly associated with CIA alone in adolescents and with CIA + stress in adults. That the number of CeA neurons expressing CCL2 was altered after CIA and stress is consistent with CCL2 involvement in neural function.

  9. Nonlinear Dot Plots.

    Science.gov (United States)

    Rodrigues, Nils; Weiskopf, Daniel

    2018-01-01

    Conventional dot plots use a constant dot size and are typically applied to show the frequency distribution of small data sets. Unfortunately, they are not designed for a high dynamic range of frequencies. We address this problem by introducing nonlinear dot plots. Adopting the idea of nonlinear scaling from logarithmic bar charts, our plots allow for dots of varying size so that columns with a large number of samples are reduced in height. For the construction of these diagrams, we introduce an efficient two-way sweep algorithm that leads to a dense and symmetrical layout. We compensate aliasing artifacts at high dot densities by a specifically designed low-pass filtering method. Examples of nonlinear dot plots are compared to conventional dot plots as well as linear and logarithmic histograms. Finally, we include feedback from an expert review.

  10. Updated version of the DOT 4 one- and two-dimensional neutron/photon transport code

    International Nuclear Information System (INIS)

    Rhoades, W.A.; Childs, R.L.

    1982-07-01

    DOT 4 is designed to allow very large transport problems to be solved on a wide range of computers and memory arrangements. Unusual flexibilty in both space-mesh and directional-quadrature specification is allowed. For example, the radial mesh in an R-Z problem can vary with axial position. The directional quadrature can vary with both space and energy group. Several features improve performance on both deep penetration and criticality problems. The program has been checked and used extensively

  11. Spectroscopic characteristics of carbon dots (C-dots) derived from carbon fibers and conversion to sulfur-bridged C-dots nanosheets.

    Science.gov (United States)

    Vinci, John C; Ferrer, Ivonne M; Guterry, Nathan W; Colón, Verónica M; Destino, Joel F; Bright, Frank V; Colón, Luis A

    2015-09-01

    We synthesized sub-10 nm carbon nanoparticles (CNPs) consistent with photoluminescent carbon dots (C-dots) from carbon fiber starting material. The production of different C-dots fractions was monitored over seven days. During the course of the reaction, one fraction of C-dots species with relatively high photoluminescence was short-lived, emerging during the first hour of reaction but disappearing after one day of reaction. Isolation of this species during the first hour of the reaction was crucial to obtaining higher-luminescent C-dots species. When the reaction proceeded for one week, the appearance of larger nanostructures was observed over time, with lateral dimensions approaching 200 nm. The experimental evidence suggests that these larger species are formed from small C-dot nanoparticles bridged together by sulfur-based moieties between the C-dot edge groups, as if the C-dots polymerized by cross-linking the edge groups through sulfur bridges. Their size can be tailored by controlling the reaction time. Our results highlight the variety of CNP products, from sub-10 nm C-dots to ~200 nm sulfur-containing carbon nanostructures, that can be produced over time during the oxidation reaction of the graphenic starting material. Our work provides a clear understanding of when to stop the oxidation reaction during the top-down production of C-dots to obtain highly photoluminescent species or a target average particle size.

  12. Photostable epoxy polymerized carbon quantum dots luminescent thin films and the performance study

    Directory of Open Access Journals (Sweden)

    Chang Zhang

    Full Text Available High photostable epoxy polymerized carbon quantum dots (C-dots luminescent thin films were prepared and their performances were compared with the CdTe quantum dots (QDs. First, water soluble C-dots (λem = 543.60 nm were synthesized. Poly (ethylene glycol diglycidyl ether (PEG and diaminooctane were used as the polymer matrix to make the epoxy resin films. FT-IR spectra showed that there were vibration at 3448 cm−1 and 1644 cm−1 which contributed to -OH and -NH respectively. SEM observations showed that the polymerizations of the films were uniform and there were no structure defects. Mechanical tests showed the tensile modulus of C-dots composite films were 4.6, 4.9, 6.4 and 7.8 MPa respectively with corresponding 0%, 1%, 2% and 5% mass fraction of C-dots, while the tensile modulus of CdTe QDs films were 4.6 MPa under the same mass fraction of CdTe QDs. Compared with semiconductor QDs, the decay of quantum yield were 5% and 10% for the C-dots and CdTe QDs, respectively. The pictures in the continuous irradiation of 48 h showed that the C-dots film was more photostable. This study provides much helpful and profound towards the fluorescent enhancement films in the field of flexible displays. Keywords: Carbon-dots, Waterborne epoxy resin, Luminescent materials, Quantum dots displays

  13. Protein engineering of the chemokine CCL20 prevents psoriasiform dermatitis in an IL-23-dependent murine model

    DEFF Research Database (Denmark)

    Getschman, A E; Imai, Y; Larsen, O

    2017-01-01

    signaling. When given in an IL-23-dependent mouse model for psoriasis, CCL20 S64C prevented psoriatic inflammation and the up-regulation of IL-17A and IL-22. Our results validate CCR6 as a tractable therapeutic target for psoriasis and demonstrate the value of CCL20 S64C as a lead compound....

  14. Hubble's View of Little Blue Dots

    Science.gov (United States)

    Kohler, Susanna

    2018-02-01

    with masses spanning 105.8107.4solar masses, specific star formation rates of 10-7.4, and redshifts of 0.5 z 5.4.Exploring these little blue dots, the Elmegreens find that the galaxies sizes tend to be just a few hundred light-years across. They are gas-dominated; gas currently outweighs stars in these galaxies by perhaps a factor of five. Impressively, based on the incredibly high specific star formation rates observed in these little blue dots, they appear to have formed all of their stars in the last 1% of the age of the universe for them.An Origin for Globulars?Log-log plot of star formation rate vs. mass for the three main groups of little blue dots (red, green, and blue markers), a fourth group of candidates with different properties (brown markers), and previously discovered local blueberry galaxies. The three main groups of little blue dots appear to be low-mass analogs of blueberries. [Elmegreen Elmegreen 2017]Intriguingly, this rapid star formation might be the key to answering a long-standing question: where do globular clusters come from? The Elmegreens propose that little blue dots might actually be an explanation for the origin of these orbiting, spherical, low-metallicity clusters of stars.The authors demonstrate that, if the current star formation rates observed in little blue dots were to persist for another 50 Myr before feedback or gas exhaustion halted star production, the little blue dots could form enough stars to create clusters of roughly a million solar masses which is large enough to explain the globular clusters we observe today.If little blue dots indeed rapidly produced such star clusters in the past, the clusters could later be absorbed into the halos of todays spiral and elliptical galaxies, appearing to us as the low-metallicity globular clusters that orbit large galaxies today.CitationDebra Meloy Elmegreen and Bruce G. Elmegreen 2017 ApJL 851 L44. doi:10.3847/2041-8213/aaa0ce

  15. The Increased Expression of CCL20 and CCR6 in Rectal Mucosa Correlated to Severe Inflammation in Pediatric Ulcerative Colitis

    Directory of Open Access Journals (Sweden)

    Keiichi Uchida

    2015-01-01

    Full Text Available Background/Aims. The aim of this study is to clarify the differences of CCL20 and CCR6 expression, chemokine correlated to intestinal homeostasis, between pediatric and adult ulcerative colitis (UC patients. Methods. Onehundred forty-one patients who underwent proctocolectomy were divided to two groups including childhood-onset UC (CUC, <16 years old, n=24 and adult-onset UC (AUC, ≧16 years old, n=117. A total of 141 formalin-fixed, paraffin-embedded tissue samples of rectum were obtained from these patients. Histological inflammation of rectum in resected specimen was evaluated by using Geboes histological assessment. In immunohistochemistry study, the CCL20 expression was evaluated by intensity and the stained area, and the CCR6 expression was evaluated by lymphocytes infiltration pattern. Results. CCL20 score and CCR6 positive lymphocytes infiltration pattern were statistically significantly correlated with histological inflammation severity of UC in all patients (P<0.05. CCL20 and CCR6 expression in CUC were statistically significantly higher than that in AUC in all or pathologically severe cases (P<0.05. Conclusions. CCL20 and CCR6 may play a significant role in local damage and pathological changes in UC especially pediatric patients. In the future, our understanding of the differences in CCL-CCR6 interaction between adults and children may lead to the pathogenesis of IBD.

  16. Charge sensing of a few-donor double quantum dot in silicon

    Energy Technology Data Exchange (ETDEWEB)

    Watson, T. F., E-mail: tfwatson15@gmail.com; Weber, B.; Büch, H.; Fuechsle, M.; Simmons, M. Y., E-mail: michelle.simmons@unsw.edu.au [Australian Research Council Centre of Excellence for Quantum Computation and Communication Technology, University of New South Wales, Sydney, New South Wales 2052 (Australia)

    2015-12-07

    We demonstrate the charge sensing of a few-donor double quantum dot precision placed with atomic resolution scanning tunnelling microscope lithography. We show that a tunnel-coupled single electron transistor (SET) can be used to detect electron transitions on both dots as well as inter-dot transitions. We demonstrate that we can control the tunnel times of the second dot to the SET island by ∼4 orders of magnitude by detuning its energy with respect to the first dot.

  17. Gunn's dots in retinal images of 2,286 adolescents

    DEFF Research Database (Denmark)

    Boberg-Ans, Lars C.; Munch, Inger C.; Larsen, Michael

    2017-01-01

    a 6 mm grid centered on the optic disc. Results: One or more Gunn's dots were seen in at least one eye in 82.6% of children. The median number of Gunn's dots per eye was 46 (range 0-482). Most Gunn's dots were found inferior and superior of the optic disc (49.3% and 45.8%, respectively, of the total...... number of Gunn's dots in the population). The odds for having 1 or more Gunn's dots were 3-fold greater in children with dark brown irides compared with children with blue irides (odds ratio 2.99, 95% CI 1.81 to 4.94, P, 0.0001 adjusted for age, sex, retinal nerve fiber layer thickness, refraction...

  18. Bifunctional NaYF4:Er3+/Yb3+ submicron rods, implemented in quantum dot sensitized solar cell(Conference Presentation)

    Science.gov (United States)

    Guerrero, J. Pablo; Cerdán Pasarán, Andrea; López-Luke, Tzarara; Ramachari, D.; Esparza, Diego; De la Rosa Cruz, Elder; Romero Arellano, Victor Hugo

    2016-09-01

    In this work are presented the results obtained with solar cells sensitized with quantum dots of cadmium sulphide (CdS) incorporating luminescent materials (NaYF4:Yb/Er). The study revealed that through using a bifunctional layer of NaYF4:Yb/Er submicron rods, the infrared radiation is absorbed in 980nm to generate luminescence in the visible region to 530nm, under the UP-conversion process, in the same way simultaneously, NaYF4:Yb/Er layer causes scattering toward the quantum dots, the emission and scattering generated by this material is reabsorbed by the QD-CdS, and these in turn are absorbing in its range of solar radiation absorption, Thus generates an increase in the electron injection into the semiconductor of TiO2. The results of a cell incorporating NaYF4: Yb/Er at 0.07M shown photoconversion efficiencies of 3.39% improving efficiency with respect to the reference solar cell without using NaYF4: Yb/Er of 1.99%. The obtained values of current and voltage showed a strong dependence of the percentage of NaYF4 Yb/Er, and the mechanism of incorporation of this material.

  19. Cyr61/CCN1 induces CCL20 production by keratinocyte via activating p38 and JNK/AP-1 pathway in psoriasis.

    Science.gov (United States)

    Li, Huidan; Li, Haichuan; Huo, Rongfen; Wu, Pinru; Shen, Zhengyu; Xu, Hui; Shen, Baihua; Li, Ningli

    2017-10-01

    Psoriasis is a common chronic skin disease characterized by epidermal hyperplasia and inflammation. Cysteine-rich angiogenic inducer 61 (Cyr61/CCN1) has recently been implicated in psoriasis pathogenesis by promoting keratinocyte activation. However, the mechanisms by which CCN1 enhances cutaneous inflammation are not fully understood. In this study, we investigated the role of CCN1 on the expression of CCL20 in human keratinocyte. By double-label immunofluorescence staining, we first identified that the expression of CCN1 colocalized well with CCL20 production in the epidermis of psoriasis skin lesion. Furthermore, in vivo, blocking or knockdown CCN1 expression ameliorated skin inflammation and reduced the expression of CCL20 in both imiquimod and IL-23-induced psoriasis-like mouse models, which indicated that CCN1 might be involved in the regulation of CCL20 production in psoriasis. Next, in vitro, we stimulated primary normal human epidermal keratinocyte (NHEK) with exogenous protein CCN1 and found that CCN1 directly upregulated CCL20 production independent of TNF-α, IL-22 and IL-17 pathway. Lastly, the signaling pathway study showed that CCN1 enhanced the binding of AP-1 to the CCL20 promoter via crosstalk with p38 and JNK. Our study demonstrates that CCN1 stimulates CCL20 production in vitro and in vivo, and thus supports the notion that overexpressed CCN1 in hyperproliferating keratinocyte is functionally involved in the recruitment of inflammatory cells to skin lesions affected by psoriasis. Copyright © 2017 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.

  20. Hepatoprotective effect of Solanum xanthocarpum fruit extract against CCl4 induced acute liver toxicity in experimental animals.

    Science.gov (United States)

    Gupta, Ramesh K; Hussain, Talib; Panigrahi, G; Das, Avik; Singh, Gireesh Narayan; Sweety, K; Faiyazuddin, Md; Rao, Chandana Venkateswara

    2011-12-01

    To investigate the hepatoprotective potential of Solanum xanthocarpum (Solanaceae) (S. xanthocarpum) in experimental rats to validate its traditional claim. 50% ethanolic fruit extract of S. xanthocarpum (SXE, 100, 200 or 400 mg/kg body weight) was administered daily for 14 days in experimental animals. Liver injury was induced chemically, by CCl(4) administration (1 mL/kg i. p.). The hepatoprotective activity was assessed using various biochemical parameters like aspartate aminotransferase (AST), alanine aminotransferase (ALT), Serum alkaline phosphatise (SALP) and total bilirubin. Meanwhile, in vivo antioxidant activities as lipid peroxidation (LPO), reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) were screened along with histopathological studies. Obtained results demonstrated that the treatment with SXE significantly (P<0.05-<0.001) and dose-dependently prevented chemically induced increase in serum levels of hepatic enzymes. Furthermore, SXE significantly (up to P<0.001) reduced the lipid peroxidation in the liver tissue and restored activities of defence antioxidant enzymes GSH, SOD and catalase towards normal levels. Histopathology of the liver tissue showed that SXE attenuated the hepatocellular necrosis and led to reduction of inflammatory cells inflltration. The results of this study strongly indicate the protective effect of SXE against acute liver injury which may be attributed to its hepatoprotective activity, and there by scientifically support its traditional use. Copyright © 2011 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  1. Spin storage in quantum dot ensembles and single quantum dots

    International Nuclear Information System (INIS)

    Heiss, Dominik

    2009-01-01

    This thesis deals with the investigation of spin relaxation of electrons and holes in small ensembles of self-assembled quantum dots using optical techniques. Furthermore, a method to detect the spin orientation in a single quantum dot was developed in the framework of this thesis. A spin storage device was used to optically generate oriented electron spins in small frequency selected quantum dot ensembles using circularly polarized optical excitation. The spin orientation can be determined by the polarization of the time delayed electroluminescence signal generated by the device after a continuously variable storage time. The degree of spin polarized initialization was found to be limited to 0.6 at high magnetic fields, where anisotropic effects are compensated. The spin relaxation was directly measured as a function of magnetic field, lattice temperature and s-shell transition energy of the quantum dot by varying the spin storage time up to 30 ms. Very long spin lifetimes are obtained with a lower limit of T 1 =20 ms at B=4 T and T=1 K. A strong magnetic field dependence T 1 ∝B -5 has been observed for low temperatures of T=1 K which weakens as the temperature is increased. In addition, the temperature dependence has been determined with T 1 ∝T -1 . The characteristic dependencies on magnetic field and temperature lead to the identification of the spin relaxation mechanism, which is governed by spin-orbit coupling and mediated by single phonon scattering. This finding is qualitatively supported by the energy dependent measurements. The investigations were extended to a modified device design that enabled studying the spin relaxation dynamics of heavy holes in self-assembled quantum dots. The measurements show a polarization memory effect for holes with up to 0.1 degree of polarization. Furthermore, investigations of the time dynamics of the hole spin relaxation reveal surprisingly long lifetimes T 1 h in the microsecond range, therefore, comparable with

  2. Spin storage in quantum dot ensembles and single quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Heiss, Dominik

    2009-10-15

    This thesis deals with the investigation of spin relaxation of electrons and holes in small ensembles of self-assembled quantum dots using optical techniques. Furthermore, a method to detect the spin orientation in a single quantum dot was developed in the framework of this thesis. A spin storage device was used to optically generate oriented electron spins in small frequency selected quantum dot ensembles using circularly polarized optical excitation. The spin orientation can be determined by the polarization of the time delayed electroluminescence signal generated by the device after a continuously variable storage time. The degree of spin polarized initialization was found to be limited to 0.6 at high magnetic fields, where anisotropic effects are compensated. The spin relaxation was directly measured as a function of magnetic field, lattice temperature and s-shell transition energy of the quantum dot by varying the spin storage time up to 30 ms. Very long spin lifetimes are obtained with a lower limit of T{sub 1}=20 ms at B=4 T and T=1 K. A strong magnetic field dependence T{sub 1}{proportional_to}B{sup -5} has been observed for low temperatures of T=1 K which weakens as the temperature is increased. In addition, the temperature dependence has been determined with T{sub 1}{proportional_to}T{sup -1}. The characteristic dependencies on magnetic field and temperature lead to the identification of the spin relaxation mechanism, which is governed by spin-orbit coupling and mediated by single phonon scattering. This finding is qualitatively supported by the energy dependent measurements. The investigations were extended to a modified device design that enabled studying the spin relaxation dynamics of heavy holes in self-assembled quantum dots. The measurements show a polarization memory effect for holes with up to 0.1 degree of polarization. Furthermore, investigations of the time dynamics of the hole spin relaxation reveal surprisingly long lifetimes T{sub 1}{sup h

  3. Leukotactin-1/CCL15 induces cell migration and differentiation of human eosinophilic leukemia EoL-1 cells through PKCdelta activation.

    Science.gov (United States)

    Lee, Ji-Sook; Kim, In Sik

    2010-06-01

    Leukotactin-1 (Lkn-1)/CCL15 is a CC chemokine that binds to the CCR1 and CCR3. Lkn-1 functions as an essential factor in the migration of monocytes, lymphocytes, and neutrophils. Although eosinophils express both receptors, the role of Lkn-1 in immature eosinophils remains to be elucidated. In this present study, we investigated the contribution of the CCR1-binding chemokines to chemotactic activity and in the differentiation in the human eosinophilic leukemia cell line EoL-1. Lkn-1 induced the stronger migration of EoL-1 cells than other CCR1-binding chemokines such as RANTES/CCL5, MIP-1alpha/CCL3 and HCC-4/CCL16. Lkn-1-induced chemotaxis was inhibited by pertussis toxin, an inhibitor of G(i)/G(o) protein; U73122, an inhibitor of phospholipase C and rottlerin, an inhibitor of protein kinase C delta (PKCdelta). Lkn-1 increased PKCdelta activity, which was partially blocked by the pertussis toxin and U73122. Lkn-1 enhanced the butyric acid-induced differentiation via PKCdelta after binding to the increased CCR1 because Lkn-1 caused EoL-1 cells to change morphologically into mature eosinophil-like cells. Likewise, Lkn-1 increased the expression of both eosinophil peroxidase (EPO) and the major basic protein (MBP). PKCdelta activation due to Lkn-1 is involved in migration, as well as the butyric acid-induced differentiation. This finding contributes to an understanding of CC chemokines in eosinophil biology and to the development of novel therapies for the treatment of eosinophilic disorders. This study suggests the pivotal roles of Lkn-1 in the regulation of the movement and development of eosinophils.

  4. Multifunctional SA-PProDOT Binder for Lithium Ion Batteries.

    Science.gov (United States)

    Ling, Min; Qiu, Jingxia; Li, Sheng; Yan, Cheng; Kiefel, Milton J; Liu, Gao; Zhang, Shanqing

    2015-07-08

    An environmentally benign, highly conductive, and mechanically strong binder system can overcome the dilemma of low conductivity and insufficient mechanical stability of the electrodes to achieve high performance lithium ion batteries (LIBs) at a low cost and in a sustainable way. In this work, the naturally occurring binder sodium alginate (SA) is functionalized with 3,4-propylenedioxythiophene-2,5-dicarboxylic acid (ProDOT) via a one-step esterification reaction in a cyclohexane/dodecyl benzenesulfonic acid (DBSA)/water microemulsion system, resulting in a multifunctional polymer binder, that is, SA-PProDOT. With the synergetic effects of the functional groups (e.g., carboxyl, hydroxyl, and ester groups), the resultant SA-PProDOT polymer not only maintains the outstanding binding capabilities of sodium alginate but also enhances the mechanical integrity and lithium ion diffusion coefficient in the LiFePO4 (LFP) electrode during the operation of the batteries. Because of the conjugated network of the PProDOT and the lithium doping under the battery environment, the SA-PProDOT becomes conductive and matches the conductivity needed for LiFePO4 LIBs. Without the need of conductive additives such as carbon black, the resultant batteries have achieved the theoretical specific capacity of LiFePO4 cathode (ca. 170 mAh/g) at C/10 and ca. 120 mAh/g at 1C for more than 400 cycles.

  5. Dendritic cell CNS recruitment correlates with disease severity in EAE via CCL2 chemotaxis at the blood–brain barrier through paracellular transmigration and ERK activation

    Directory of Open Access Journals (Sweden)

    Sagar Divya

    2012-10-01

    Full Text Available Abstract Background Transmigration of circulating dendritic cells (DCs into the central nervous system (CNS across the blood–brain barrier (BBB has not thus far been investigated. An increase in immune cell infiltration across the BBB, uncontrolled activation and antigen presentation are influenced by chemokines. Chemokine ligand 2 (CCL2 is a potent chemoattractant known to be secreted by the BBB but has not been implicated in the recruitment of DCs specifically at the BBB. Methods Experimental autoimmune encephalomyelitis (EAE was induced in C57BL/6 mice by injection of MOG35–55 peptide and pertussis toxin intraperitoneally. Animals with increasing degree of EAE score were sacrificed and subjected to near-infrared and fluorescence imaging analysis to detect and localize the accumulation of CD11c+-labeled DCs with respect to CCL2 expression. To further characterize the direct effect of CCL2 in DC trafficking at the BBB, we utilized an in vitro BBB model consisting of human brain microvascular endothelial cells to compare migratory patterns of monocyte-derived dendritic cells, CD4+ and CD8+ T cells. Further, this model was used to image transmigration using fluorescence microcopy and to assess specific molecular signaling pathways involved in transmigration. Results Near-infrared imaging of DC transmigration correlated with the severity of inflammation during EAE. Ex vivo histology confirmed the presence of CCL2 in EAE lesions, with DCs emerging from perivascular spaces. DCs exhibited more efficient transmigration than T cells in BBB model studies. These observations correlated with transwell imaging, which indicated a paracellular versus transcellular pattern of migration by DCs and T cells. Moreover, at the molecular level, CCL2 seems to facilitate DC transmigration in an ERK1/2-dependent manner. Conclusion CNS recruitment of DCs correlates with disease severity in EAE via CCL2 chemotaxis and paracellular transmigration across the BBB

  6. ZZ CAD, 51 Neutron-Group, 25 Gamma-Group Albedo Data for 4 Materials from DOT Flux

    International Nuclear Information System (INIS)

    1992-01-01

    A - Description of problem or function: Format: BREESE tape-writing program, MORSE; Number of groups: 51 neutron, 25 gamma-ray group albedo data. Nuclides: 1) 12 inches of water. 2) 12 inches of ordinary concrete. 3) 9 inches of carbon steel (SA508). 4) 1/2 inches of steel over 12 inches of concrete. (O, Ca, Al, C, Si, H, K, Mg, Fe, Na, Mn); Origin: DOT angular flux tape. CAD is a set of 51 neutron, 25 gamma-ray group albedo data for the following four materials: 1) 12 inches of water. 2) 12 inches of ordinary concrete. 3) 9 inches of carbon steel (SA508). 4) 1/2 inches of steel over 12 inches of concrete. The differential angular albedos are a function of the five incident polar directions and 30 reflected directions. B - Method of solution: The data has been generated from a DOT angular flux tape using the code CARP (abstract PSR-0131). C - Restrictions on the complexity of the problem: Since the amount of data is so large, it is necessary to run CARP, using the group reduction option, in order to run a problem on most computers

  7. Carbon Dots/NiCo2 O4 Nanocomposites with Various Morphologies for High Performance Supercapacitors.

    Science.gov (United States)

    Wei, Ji-Shi; Ding, Hui; Zhang, Peng; Song, Yan-Fang; Chen, Jie; Wang, Yong-Gang; Xiong, Huan-Ming

    2016-11-01

    A series of carbon dots/NiCo 2 O 4 composites with various morphologies are prepared and tested for supercapacitors. These samples have good electrical conductivities and efficient ions transport paths, so they exhibit high specific capacitances, superior rate performances, and high cycling stabilities. The optimal composite for hybrid supercapacitor exhibits a high energy density up to 62.0 Wh kg -1 . © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Strong-coupling polaron effect in quantum dots

    International Nuclear Information System (INIS)

    Zhu Kadi; Gu Shiwei

    1993-11-01

    Strong-coupling polaron in a parabolic quantum dot is investigated by the Landau-Pekar variational treatment. The polaron binding energy and the average number of virtual phonons around the electron as a function of the effective confinement length of the quantum dot are obtained in Gaussian function approximation. It is shown that both the polaron binding energy and the average number of virtual phonons around the electron decrease by increasing the effective confinement length. The results indicate that the polaronic effects are more pronounced in quantum dots than those in two-dimensional and three-dimensional cases. (author). 15 refs, 4 figs

  9. A study on socio-demographic profile and feasibility of DOTS provider registered under RNTCP in Varanasi district Uttar Pradesh

    Directory of Open Access Journals (Sweden)

    Mohd. Afzalul Haque

    2014-03-01

    Full Text Available Introduction: Tuberculosis is a major chronic disorder affecting the larger population more than any other disease in the country. DOTS was introduced in India in 1993 as part of the Revised National Tuberculosis Programme (RNTCP following a review of India’s National Tuberculosis Programme (NTP a year earlier (1 .Patient satisfaction is an important parameter for assessing the quality of patient care services. There is need to assess the health care provider regarding the consumer satisfaction as often as possible, this paper summarizes our experience about role of DOTS provider in the management of TB patient in rural population of Varanasi districts Utter Pradesh. Objective: (1 To assess the perception of registered tuberculosis patients regarding DOTS provider for the treatment of tuberculosis. (2 To assess the accessibility, acceptability & availability of community DOTS provider. Design: A longitudinal study. Setting: Three microscopic centre of Cholapur Tuberculosis unit of Varanasi districts. Methods: Registered patients were interviewed twice: once in the beginning and another at the completion of the treatment or after the permanent discontinuation of the treatment. Patients were interviewed for their socio-demographic profiles, opinion about DOTS and its providers. Side effects experienced and action taken etc. Data was collected on a semi-structured, pre-tested questionnaire. DOTS providers were interviewed and treatment cards analyzed for any interruption of treatment and action taken. Data was collected from 1st June 2004 to 31th June 2005 till the completion of the regimen. Results: Majority of DOTS providers were young males (82.7% of 26 years to 40 years, while the representation of females was only 5 (17.3%. Almost more than 80% of the patients started their treatment within 1-10 days. For majority of cases (83% the distance of DOTS provider from patient’s house was within 1 km. Mean time spent to go to DOTS provider was 27

  10. Energies and wave functions of an off-centre donor in hemispherical quantum dot: Two-dimensional finite difference approach and ritz variational principle

    Energy Technology Data Exchange (ETDEWEB)

    Nakra Mohajer, Soukaina; El Harouny, El Hassan [Laboratoire de Physique de la Matière Condensée, Département de Physique, Faculté des Sciences, Université Abdelmalek Essaadi, B.P. 2121 M’Hannech II, 93030 Tétouan (Morocco); Ibral, Asmaa [Equipe d’Optique et Electronique du Solide, Département de Physique, Faculté des Sciences, Université Chouaïb Doukkali, B. P. 20 El Jadida Principale, El Jadida (Morocco); Laboratoire d’Instrumentation, Mesure et Contrôle, Département de Physique, Faculté des Sciences, Université Chouaïb Doukkali, B. P. 20 El Jadida Principale, El Jadida (Morocco); El Khamkhami, Jamal [Laboratoire de Physique de la Matière Condensée, Département de Physique, Faculté des Sciences, Université Abdelmalek Essaadi, B.P. 2121 M’Hannech II, 93030 Tétouan (Morocco); and others

    2016-09-15

    Eigenvalues equation solutions of a hydrogen-like donor impurity, confined in a hemispherical quantum dot deposited on a wetting layer and capped by an insulating matrix, are determined in the framework of the effective mass approximation. Conduction band alignments at interfaces between quantum dot and surrounding materials are described by infinite height barriers. Ground and excited states energies and wave functions are determined analytically and via one-dimensional finite difference approach in case of an on-center donor. Donor impurity is then moved from center to pole of hemispherical quantum dot and eigenvalues equation is solved via Ritz variational principle, using a trial wave function where Coulomb attraction between electron and ionized donor is taken into account, and by two-dimensional finite difference approach. Numerical codes developed enable access to variations of donor total energy, binding energy, Coulomb correlation parameter, spatial extension and radial probability density with respect to hemisphere radius and impurity position inside the quantum dot.

  11. Energies and wave functions of an off-centre donor in hemispherical quantum dot: Two-dimensional finite difference approach and ritz variational principle

    International Nuclear Information System (INIS)

    Nakra Mohajer, Soukaina; El Harouny, El Hassan; Ibral, Asmaa; El Khamkhami, Jamal

    2016-01-01

    Eigenvalues equation solutions of a hydrogen-like donor impurity, confined in a hemispherical quantum dot deposited on a wetting layer and capped by an insulating matrix, are determined in the framework of the effective mass approximation. Conduction band alignments at interfaces between quantum dot and surrounding materials are described by infinite height barriers. Ground and excited states energies and wave functions are determined analytically and via one-dimensional finite difference approach in case of an on-center donor. Donor impurity is then moved from center to pole of hemispherical quantum dot and eigenvalues equation is solved via Ritz variational principle, using a trial wave function where Coulomb attraction between electron and ionized donor is taken into account, and by two-dimensional finite difference approach. Numerical codes developed enable access to variations of donor total energy, binding energy, Coulomb correlation parameter, spatial extension and radial probability density with respect to hemisphere radius and impurity position inside the quantum dot.

  12. PennDOT : fact book

    Science.gov (United States)

    2008-06-01

    PennDOT was created in 1970 when the former : Department of Highways was merged with transportation related : functions from the Departments of Revenue, : Commerce, Community Affairs and Military Affairs. With : an annual budget of about $5.4 billion...

  13. Killed Whole-Cell Oral Cholera Vaccine Induces CCL20 Secretion by Human Intestinal Epithelial Cells in the Presence of the Short-Chain Fatty Acid, Butyrate

    Directory of Open Access Journals (Sweden)

    Ju-Ri Sim

    2018-01-01

    Full Text Available Short-chain fatty acids (SCFAs, such as acetate, butyrate, and propionate, modulate immune responses in the gut. However, the effect of SCFAs on mucosal vaccine-induced immune cell migration is poorly understood. Here, we investigated whether SCFAs modulate chemokine expression induced by the killed whole-cell oral cholera vaccine, Shanchol™, in human intestinal epithelial cells. Shanchol™ induced expression of CCL2, CCL5, CCL20, and CXCL10 at the mRNA level, but not at the protein level. Interestingly, CCL20 secretion was substantially increased by co-stimulation with Shanchol™ and butyrate, while neither acetate nor propionate showed such effect. Enhanced CCL20 secretion was associated with GPR109A activation, and histone deacetylase (HDAC inhibition. In addition, co-treatment with Shanchol™ and butyrate synergistically increased the secretion of adenosine triphosphate (ATP. Moreover, CCL20 secretion was decreased by inhibiting the extracellular ATP receptor P2X7. However, neither inflammasomes nor caspases were involved in CCL20 production. The culture supernatant of cells treated with Shanchol™ and butyrate augmented human immature dendritic cell migration. Collectively, these results suggest that butyrate enhances Shanchol™-induced CCL20 production in human intestinal epithelial cells via HDAC inhibition and ATP-P2X7 signaling by activating GPR109A. These effects potentially enhance the mucosal immune responses in the gut induced by this oral cholera vaccine.

  14. A cross-sectional study: serum CCL3/MIP-1α levels may reflect lumbar intervertebral disk degeneration in Han Chinese people

    Directory of Open Access Journals (Sweden)

    Zhang YL

    2018-03-01

    Full Text Available Yi-Li Zhang,1,2,* Bei Li,1,2,* Zeng-Huan Zhou1 1School of Public Health, Southern Medical University, Guangzhou, Guangdong Province, People’s Republic of China; 2School of Health Services Management, Southern Medical University, Guangzhou, Guangdong Province, People’s Republic of China *These authors contributed equally to this work Background: The macrophage inflammatory protein-1α (MIP-1α, also named chemokine cytokine ligand 3 (CCL3, has been detected in nucleus pulposus and increased following cytokine stimulation. Objective: The current study was performed to explore the relationship between serum CCL3/MIP-1α levels with lumbar intervertebral disk degeneration (IDD. Patients and methods: A total of 132 disk degeneration patients confirmed by magnetic resonance imaging and 126 healthy controls were enrolled in the current study. Radiological evaluation of the IDD was conducted using a 3.0-T magnetic resonance imaging scanner for entire lumbar vertebra region. Degeneration of intervertebral disk was assessed by Schneiderman criteria. Serum CCL3/MIP-1α levels were investigated using a sandwich enzyme-linked immunosorbent assay. The Visual Analog Scale scores and Oswestry Disability Index index were recorded for clinical severity. Results: Elevated concentrations of CCL3 in serum were found in IDD patients compared with asymptomatic volunteers. The case group included 49 IDD patients with grade 1, 42 with grade 2, and 41 with grade 3. Grade 3 and 2 had significantly higher CCL3 concentrations in serum compared with those with grade 1. The serum CCL3 levels were positively related to the degree of disk degeneration. In addition, the serum CCL3 levels also demonstrated a significant correlation with the clinical severity determined by Visual Analog Scale scores and Oswestry Disability Index index. Conclusion: Serum CCL3 may serve as a biomarker of IDD. Keywords: chemokine cytokine ligand 3, intervertebral disk degeneration, cross

  15. [CCL21 promotes the metastasis of human pancreatic cancer Panc-1 cells via epithelial- mesenchymal transition].

    Science.gov (United States)

    Liu, Qing; Chen, Fangfang; Duan, Tanghai; Zhu, Haitao; Xie, Xiaodong; Wu, Yingying; Zhang, Zhijian; Wang, Dongqing

    2015-01-01

    To investigate the mechanism underlying that chemokine (C-C motif) ligand 21 (CCL21) promotes the metastasis ability of human pancreatic cancer Panc-1 cells. Transwell(TM) was used to access the chemotaxis effect of CCL21 on Panc-1 cells. Real-time quantitative PCR was performed to detect the expression of C-C chemokine receptor type 7 (CCR7) mRNA in the upper and lower chambers. Immunofluorescence staining and Western blotting were employed to examine the expressions of the epithelial-mesenchymal transition (EMT)-related proteins and CD133 of Panc-1 cells in the lower chamber, which were compared with those of the upper chamber as the control. The numbers of the Panc-1 cells induced by 0, 50, 100, 200 ng/mL CCL21 were 13.00 ± 3.00, 78.00 ± 9.00, 161.00 ± 11.00, 281.00 ± 17.00, respectively; with the increase of the concentration of CCL21, there were more cells migrating from the upper to the lower chamber; and the cells in the lower chamber expressed higher level of CCR7 mRNA than the ones staying in the upper chamber. The relative protein expressions of MMP-9, vimentin, E-cadherin and CD133 in the lower chamber were 0.42 ± 0.04, 0.36 ± 0.03, 0.12 ± 0.02, 0.46 ± 0.03, respectively, which were statistically significantly different from those in the upper chamber (0.15 ± 0.02, 0.25 ± 0.02, 0.25 ± 0.03, 0.13 ± 0.02, respectively). CCL21/CCR7 axis maybe play an important role in the metastasis of pancreatic cancer stem cells by EMT and up-regulation of MMP-9.

  16. Community Documentation Centre on Industrial Risk. Bulletin no. 4

    International Nuclear Information System (INIS)

    Gow, H.B.F.

    1991-01-01

    The Directorate-General for Environment, Nuclear Safety and Civil Protection of the Commission of the European Communities is responsible for the effective and harmonized implementation of the Directive 82/501/EEC on the major-accident hazards of certain industrial activities. To this end, the Commission, in collaboration with the Committee of Competent Authorities responsible for the implementation of this Directive in the twelve Member States, carries out a whole range of activities. One of the most essential areas for action identified was the need for a systematic diffusion of information concerning the practical implementation of the Directive in the Member States, including the technical rules and guidelines applied, the safety practices and the lessons learnt from major accidents. Therefore, the Commission decided to set up a Community Documentation Centre on Industrial Risks (CDCIR). This Documentation Centre is run by the European Commission, Joint Research Centre, Institute for Systems Engineering and Informatics (ISEI), at Ispra, Italy, among its support activities on the implementation of the Directive. The Documentation Centre will collect, classify and review technical rules, guidelines and documents concerning the requirements of the Directive, as well as the safety of industrial installations produced by governments, administrative, scientific or technical bodies, national or international organizations and industrial or professional associations. Documents on major accidents in the form of reports, videotapes will also be collected and reviewed. The Centre is accessible to interested visitors, documents which are not covered by copyright and are not restricted can be obtained from the Documentation Centre on request. Periodical volumes which will feature the inventory, including abstracts, of the collected material will be published and made available to all interested parties. The Centre will also publish documents devoted to compare existing

  17. Computer simulation and cold model testing of CCL cavities

    International Nuclear Information System (INIS)

    Chang, C.R.; Yao, C.G.; Swenson, D.A.; Funk, L.W.

    1993-01-01

    The SSC coupled-cavity-linac (CCL) consists of nine modules with eight tanks in each module. Multicavity magnetically coupled bridge couplers are used to couple the eight tanks within a module into one RF resonant chain. The operating frequency is 1282.851 MHz. In this paper the authors discuss both computer calculations and cold model measurements to determine the geometry dimension of the RF structure

  18. Templated self-assembly of SiGe quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Dais, Christian

    2009-08-19

    This PhD thesis reports on the fabrication and characterization of exact aligned SiGe quantum dot structures. In general, SiGe quantum dots which nucleate via the Stranski-Krastanov growth mode exhibit broad size dispersion and nucleate randomly on the surface. However, to tap the full potential of SiGe quantum dots it is necessary to control the positioning and size of the dots on a nanometer length, e.g. for electronically addressing of individual dots. This can be realized by so-called templated self-assembly, which combines top-down lithography with bottom-up selfassembly. In this process the lithographically defined pits serve as pre-defined nucleation points for the epitaxially grown quantum dots. In this thesis, extreme ultraviolet interference lithography at a wavelength of e=13.4 nm is employed for prepatterning of the Si substrates. This technique allows the precise and fast fabrication of high-resolution templates with a high degree of reproducibility. The subsequent epitaxial deposition is either performed by molecular beam epitaxy or low-pressure chemical vapour deposition. It is shown that the dot nucleation on pre-patterned substrates depends strongly on the lithography parameters, e.g. size and periodicity of the pits, as well as on the epitaxy parameters, e.g. growth temperature or material coverage. The interrelations are carefully analyzed by means of scanning force microscopy, transmission electron microscopy and X-ray diffraction measurements. Provided that correct template and overgrowth parameters are chosen, perfectly aligned and uniform SiGe quantum dot arrays of different period, size as well as symmetry are created. In particular, the quantum dot arrays with the so far smallest period (35 nm) and smallest size dispersion are fabricated in this thesis. Furthermore, the strain fields of the underlying quantum dots allow the fabrication of vertically aligned quantum dot stacks. Combining lateral and vertical dot alignment results in three

  19. Reassessing the role of DotF in the Legionella pneumophila type IV secretion system.

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    Molly C Sutherland

    Full Text Available Legionella pneumophila, the causative agent of a severe pneumonia termed Legionnaires' Disease, survives and replicates within both protozoan hosts and human alveolar macrophages. Intracellular survival is dependent upon secretion of a plethora of protein effectors that function to form a replicative vacuole, evade the endocytic pathway and subvert host immune defenses. Export of these factors requires a type IV secretion system (T4SS called Dot/Icm that is composed of twenty-seven proteins. This report focuses on the DotF protein, which was previously postulated to have several different functions, one of which centered on binding Dot/Icm substrates. In this report, we examined if DotF functions as the T4SS inner membrane receptor for Dot/Icm substrates. Although we were able to recapitulate the previously published bacterial two-hybrid interaction between DotF and several substrates, the interaction was not dependent on the Dot/Icm substrates' signal sequences as predicted for a substrate:receptor interaction. In addition, binding did not require the cytoplasmic domain of DotF, which was anticipated to be involved in recognizing substrates in the cytoplasm. Finally, inactivation of dotF did not abolish intracellular growth of L. pneumophila or translocation of substrates, two phenotypes dependent on the T4SS receptor. These data strongly suggest that DotF does not act as the major receptor for Dot/Icm substrates and therefore likely performs an accessory function within the core-transmembrane subcomplex of the L. pneumophila Dot/Icm type IV secretion system.

  20. A structure development in electron-irradiated type Ia diamond

    International Nuclear Information System (INIS)

    Novikov, N.V.; Ositinskaya, T.D.; Tkach, V.N.

    1998-01-01

    A type Ia diamond crystal with nitrogen impurity in different forms was irradiated by 3.5 MeV electrons with increasing doses 5 centre dot 10 16 , 2 centre dot 10 17 , 4 centre dot 10 17 , 2 centre dot 10 18 e/cm 2 and investigated before and after each dose by positron annihilation, EPR, and optical spectroscopy. After irradiation with the highest dose, the effect of development of a visible defective structure of the crystal is revealed. A description of this effect and data of EPR and IR-measurements depending on irradiation doses are presented. First results of cathodoluminescence (CL) studies in the form CL-topograms and CL-spectra for difference zones of the crystal are also given

  1. Directional secretory response of double stranded RNA-induced thymic stromal lymphopoetin (TSLP) and CCL11/eotaxin-1 in human asthmatic airways.

    Science.gov (United States)

    Nino, Gustavo; Huseni, Shehlanoor; Perez, Geovanny F; Pancham, Krishna; Mubeen, Humaira; Abbasi, Aleeza; Wang, Justin; Eng, Stephen; Colberg-Poley, Anamaris M; Pillai, Dinesh K; Rose, Mary C

    2014-01-01

    Thymic stromal lymphoproetin (TSLP) is a cytokine secreted by the airway epithelium in response to respiratory viruses and it is known to promote allergic Th2 responses in asthma. This study investigated whether virally-induced secretion of TSLP is directional in nature (apical vs. basolateral) and/or if there are TSLP-mediated effects occurring at both sides of the bronchial epithelial barrier in the asthmatic state. Primary human bronchial epithelial cells (HBEC) from control (n = 3) and asthmatic (n = 3) donors were differentiated into polarized respiratory tract epithelium under air-liquid interface (ALI) conditions and treated apically with dsRNA (viral surrogate) or TSLP. Sub-epithelial effects of TSLP were examined in human airway smooth muscle cells (HASMC) from normal (n = 3) and asthmatic (n = 3) donors. Clinical experiments examined nasal airway secretions obtained from asthmatic children during naturally occurring rhinovirus-induced exacerbations (n = 20) vs. non-asthmatic uninfected controls (n = 20). Protein levels of TSLP, CCL11/eotaxin-1, CCL17/TARC, CCL22/MDC, TNF-α and CXCL8 were determined with a multiplex magnetic bead assay. Our data demonstrate that: 1) Asthmatic HBEC exhibit an exaggerated apical, but not basal, secretion of TSLP after dsRNA exposure; 2) TSLP exposure induces unidirectional (apical) secretion of CCL11/eotaxin-1 in asthmatic HBEC and enhanced CCL11/eotaxin-1 secretion in asthmatic HASMC; 3) Rhinovirus-induced asthma exacerbations in children are associated with in vivo airway secretion of TSLP and CCL11/eotaxin-1. There are virally-induced TSLP-driven secretory immune responses at both sides of the bronchial epithelial barrier characterized by enhanced CCL11/eotaxin-1 secretion in asthmatic airways. These results suggest a new model of TSLP-mediated eosinophilic responses in the asthmatic airway during viral-induced exacerbations.

  2. Directional secretory response of double stranded RNA-induced thymic stromal lymphopoetin (TSLP and CCL11/eotaxin-1 in human asthmatic airways.

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    Gustavo Nino

    Full Text Available Thymic stromal lymphoproetin (TSLP is a cytokine secreted by the airway epithelium in response to respiratory viruses and it is known to promote allergic Th2 responses in asthma. This study investigated whether virally-induced secretion of TSLP is directional in nature (apical vs. basolateral and/or if there are TSLP-mediated effects occurring at both sides of the bronchial epithelial barrier in the asthmatic state.Primary human bronchial epithelial cells (HBEC from control (n = 3 and asthmatic (n = 3 donors were differentiated into polarized respiratory tract epithelium under air-liquid interface (ALI conditions and treated apically with dsRNA (viral surrogate or TSLP. Sub-epithelial effects of TSLP were examined in human airway smooth muscle cells (HASMC from normal (n = 3 and asthmatic (n = 3 donors. Clinical experiments examined nasal airway secretions obtained from asthmatic children during naturally occurring rhinovirus-induced exacerbations (n = 20 vs. non-asthmatic uninfected controls (n = 20. Protein levels of TSLP, CCL11/eotaxin-1, CCL17/TARC, CCL22/MDC, TNF-α and CXCL8 were determined with a multiplex magnetic bead assay.Our data demonstrate that: 1 Asthmatic HBEC exhibit an exaggerated apical, but not basal, secretion of TSLP after dsRNA exposure; 2 TSLP exposure induces unidirectional (apical secretion of CCL11/eotaxin-1 in asthmatic HBEC and enhanced CCL11/eotaxin-1 secretion in asthmatic HASMC; 3 Rhinovirus-induced asthma exacerbations in children are associated with in vivo airway secretion of TSLP and CCL11/eotaxin-1.There are virally-induced TSLP-driven secretory immune responses at both sides of the bronchial epithelial barrier characterized by enhanced CCL11/eotaxin-1 secretion in asthmatic airways. These results suggest a new model of TSLP-mediated eosinophilic responses in the asthmatic airway during viral-induced exacerbations.

  3. RANTES/CCL5 and risk for coronary events: results from the MONICA/KORA Augsburg case-cohort, Athero-Express and CARDIoGRAM studies.

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    Christian Herder

    Full Text Available The chemokine RANTES (regulated on activation, normal T-cell expressed and secreted/CCL5 is involved in the pathogenesis of cardiovascular disease in mice, whereas less is known in humans. We hypothesised that its relevance for atherosclerosis should be reflected by associations between CCL5 gene variants, RANTES serum concentrations and protein levels in atherosclerotic plaques and risk for coronary events.We conducted a case-cohort study within the population-based MONICA/KORA Augsburg studies. Baseline RANTES serum levels were measured in 363 individuals with incident coronary events and 1,908 non-cases (mean follow-up: 10.2±4.8 years. Cox proportional hazard models adjusting for age, sex, body mass index, metabolic factors and lifestyle factors revealed no significant association between RANTES and incident coronary events (HR [95% CI] for increasing RANTES tertiles 1.0, 1.03 [0.75-1.42] and 1.11 [0.81-1.54]. None of six CCL5 single nucleotide polymorphisms and no common haplotype showed significant associations with coronary events. Also in the CARDIoGRAM study (>22,000 cases, >60,000 controls, none of these CCL5 SNPs was significantly associated with coronary artery disease. In the prospective Athero-Express biobank study, RANTES plaque levels were measured in 606 atherosclerotic lesions from patients who underwent carotid endarterectomy. RANTES content in atherosclerotic plaques was positively associated with macrophage infiltration and inversely associated with plaque calcification. However, there was no significant association between RANTES content in plaques and risk for coronary events (mean follow-up 2.8±0.8 years.High RANTES plaque levels were associated with an unstable plaque phenotype. However, the absence of associations between (i RANTES serum levels, (ii CCL5 genotypes and (iii RANTES content in carotid plaques and either coronary artery disease or incident coronary events in our cohorts suggests that RANTES may not be a

  4. Facile synthetic method for pristine graphene quantum dots and graphene oxide quantum dots: origin of blue and green luminescence.

    Science.gov (United States)

    Liu, Fei; Jang, Min-Ho; Ha, Hyun Dong; Kim, Je-Hyung; Cho, Yong-Hoon; Seo, Tae Seok

    2013-07-19

    Pristine graphene quantum dots and graphene oxide quantum dots are synthesized by chemical exfoliation from the graphite nanoparticles with high uniformity in terms of shape (circle), size (less than 4 nm), and thickness (monolayer). The origin of the blue and green photoluminescence of GQDs and GOQDs is attributed to intrinsic and extrinsic energy states, respectively. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. An essential role of syntaxin 3 protein for granule exocytosis and secretion of IL-1α, IL-1β, IL-12b, and CCL4 from differentiated HL-60 cells.

    Science.gov (United States)

    Naegelen, Isabelle; Plançon, Sébastien; Nicot, Nathalie; Kaoma, Tony; Muller, Arnaud; Vallar, Laurent; Tschirhart, Eric J; Bréchard, Sabrina

    2015-03-01

    Besides their roles in the killing of pathogens, neutrophils have the capacity to package a variety of cytokines into cytoplasmic granules for subsequent release upon inflammatory conditions. Because the rapid secretion of cytokines orchestrates the action of other immune cells at the infection site and thus, can contribute to the development and chronicity of inflammatory diseases, we aimed to determine the intracellular SNARE machinery responsible for the regulation of cytokine secretion and degranulation. From a constructed gene-expression network, we first selected relevant cytokines for functional validation by the CBA approach. We established a cytokine-secretion profile for human neutrophils and dHL-60 cells, underlining their similar ability to secrete a broad variety of cytokines within proinflammatory conditions mimicked by LPS stimulation. Secondly, after screening of SNARE genes by microarray experiments, we selected STX3 for further functional studies. With the use of a siRNA strategy, we show that STX3 is clearly required for the maximal release of IL-1α, IL-1β, IL-12b, and CCL4 without alteration of other cytokine secretion in dHL-60 cells. In addition, we demonstrate that STX3 is involved in MMP-9 exocytosis from gelatinase granules, where STX3 is partly localized. Our results suggest that the secretion of IL-1α, IL-1β, IL-12b, and CCL4 occurs during gelatinase degranulation, a process controlled by STX3. In summary, these findings provide first evidence that STX3 has an essential role in trafficking pathways of cytokines in neutrophil granulocytes. © Society for Leukocyte Biology.

  6. Reduced SHARPIN and LUBAC Formation May Contribute to CCl4- or Acetaminophen-Induced Liver Cirrhosis in Mice

    Directory of Open Access Journals (Sweden)

    Takeshi Yamamotoya

    2017-02-01

    Full Text Available Linear ubiquitin chain assembly complex (LUBAC, composed of SHARPIN (SHANK-associated RH domain-interacting protein, HOIL-1L (longer isoform of heme-oxidized iron-regulatory protein 2 ubiquitin ligase-1, and HOIP (HOIL-1L interacting protein, forms linear ubiquitin on nuclear factor-κB (NF-κB essential modulator (NEMO and induces NF-κB pathway activation. SHARPIN expression and LUBAC formation were significantly reduced in the livers of mice 24 h after the injection of either carbon tetrachloride (CCl4 or acetaminophen (APAP, both of which produced the fulminant hepatitis phenotype. To elucidate its pathological significance, hepatic SHARPIN expression was suppressed in mice by injecting shRNA adenovirus via the tail vein. Seven days after this transduction, without additional inflammatory stimuli, substantial inflammation and fibrosis with enhanced hepatocyte apoptosis occurred in the livers. A similar but more severe phenotype was observed with suppression of HOIP, which is responsible for the E3 ligase activity of LUBAC. Furthermore, in good agreement with these in vivo results, transduction of Hepa1-6 hepatoma cells with SHARPIN, HOIL-1L, or HOIP shRNA adenovirus induced apoptosis of these cells in response to tumor necrosis factor-α (TNFα stimulation. Thus, LUBAC is essential for the survival of hepatocytes, and it is likely that reduction of LUBAC is a factor promoting hepatocyte death in addition to the direct effect of drug toxicity.

  7. On the geochemistry of 'Chernobyl' Cs-137 and Sr-90 in the Black Sea

    International Nuclear Information System (INIS)

    Batrakov, G.F.; Chudinovskikh, T.V.; Zemlyanoi, A.D.; Eremeev, V.N.

    1998-01-01

    The following correlations for Cs 137 and Sr 90 were found. For Cs-137, the relation of its concentration in suspended matter to that in the dissolved component is 2.4 centre dot 10 5 in the Dnieper waters and 0.0037 centre dot 10 5 in the North-West shelf waters; for Sr-90 - 0.44 centre dot 10 3 and 2.8 centre dot 10 3 , respectively. The relation of the concentration of dissolved Cs-137 in the sea and in the Dnieper waters is 4.3, and for Sr-90 - 0.25. It is evident that these basic correlations for Cs-137 are close to those for stable cesium. These correlations for Sr-90 differ very much from those for stable strontium. So, the situation formed for the last time in the boundary area 'the Dnieper river - the North-Western Black Sea' is close to the balanced one for Cs-137, while it is very far from that for Sr-90

  8. DESIGN AND ANALYSIS OF THE SNS CCL HOT MODEL WATER COOLING SYSTEM USING THE SINDA/FLUINT NETWORK MODELING TOOL

    Energy Technology Data Exchange (ETDEWEB)

    C. AMMERMAN; J. BERNARDIN

    1999-11-01

    This report presents results for design and analysis of the hot model water cooling system for the Spallation Neutron Source (SNS) coupled-cavity linac (CCL). The hot model, when completed, will include segments for both the CCL and coupled-cavity drift-tube linac (CCDTL). The scope of this report encompasses the modeling effort for the CCL portion of the hot model. This modeling effort employed the SINDA/FLUINT network modeling tool. This report begins with an introduction of the SNS hot model and network modeling using SINDA/FLUINT. Next, the development and operation of the SINDA/FLUINT model are discussed. Finally, the results of the SINDA/FLUINT modeling effort are presented and discussed.

  9. Low intraprostatic DHT promotes the infiltration of CD8+ T cells in BPH tissues via modulation of CCL5 secretion.

    Science.gov (United States)

    Fan, Yu; Hu, Shuai; Liu, Jie; Xiao, Fei; Li, Xin; Yu, Wei; Cui, Yun; Sun, Mengkui; Lv, Tianjing; He, Qun; Jin, Jie

    2014-01-01

    Clinical studies suggested thatandrogen might be associated with infiltrating T cells in prostate of benign prostatic hyperplasia (BPH) patients, but detail of T-cell subset and mechanism still remained unclear. The present study tested the hypothesis that intraprostatic 5 α -dihydrotestosterone (DHT) exerts effects on T cells recruitment by BPH epithelial cells. Prostate tissues from 64 cases of BPH patients after transurethral resection of prostate (TURP) were divided into 2 groups: (1) no medication history; (2) administration of 5 α -reductase type II inhibitor-finasteride 5 mg daily for at least 6 months before surgery. Group 2 presented significantly higher CD8+ T cells infiltration than group 1, but no changes in CD4+ T cells (immunohistochemistry and flow cytometry). In vitro study more CD8+ T cell migrated to the prostate tissue lysates from group 2 and BPH-1 cells in low DHT condition. Transcription of chemokine (C-C motif) Ligand 5 (CCL5) mRNA in BPH-1 cells and chemokine (C-C motif) receptor 5 (CCR5) mRNA in CD8+ T cells were upregulated in low DHT condition (q-PCR). CCL5 expression was also identified to be higher in group 2 prostate tissues by IHC. This study suggested that intraprostatic DHT may participate in regulating inflammatory response which was induced by human prostatic epithelial cell, via modulating CCL5 secretion.

  10. Low Intraprostatic DHT Promotes the Infiltration of CD8+ T Cells in BPH Tissues via Modulation of CCL5 Secretion

    Directory of Open Access Journals (Sweden)

    Yu Fan

    2014-01-01

    Full Text Available Clinical studies suggested thatandrogen might be associated with infiltrating T cells in prostate of benign prostatic hyperplasia (BPH patients, but detail of T-cell subset and mechanism still remained unclear. The present study tested the hypothesis that intraprostatic 5α-dihydrotestosterone (DHT exerts effects on T cells recruitment by BPH epithelial cells. Prostate tissues from 64 cases of BPH patients after transurethral resection of prostate (TURP were divided into 2 groups: (1 no medication history; (2 administration of 5α-reductase type II inhibitor-finasteride 5 mg daily for at least 6 months before surgery. Group 2 presented significantly higher CD8+ T cells infiltration than group 1, but no changes in CD4+ T cells (immunohistochemistry and flow cytometry. In vitro study more CD8+ T cell migrated to the prostate tissue lysates from group 2 and BPH-1 cells in low DHT condition. Transcription of chemokine (C-C motif Ligand 5 (CCL5 mRNA in BPH-1 cells and chemokine (C-C motif receptor 5 (CCR5 mRNA in CD8+ T cells were upregulated in low DHT condition (q-PCR. CCL5 expression was also identified to be higher in group 2 prostate tissues by IHC. This study suggested that intraprostatic DHT may participate in regulating inflammatory response which was induced by human prostatic epithelial cell, via modulating CCL5 secretion.

  11. Electron paramagnetic resonance and electron-nuclear double-resonance study of Ti{sup 3+} centres in KTiOPO{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Setzler, S D [BAE Systems, Nashua, NH 03061 (United States); Stevens, K T [Northrop Grumman, Space Technology, Synoptics, Charlotte, NC 28273 (United States); Fernelius, N C [Air Force Research Laboratory, Materials and Manufacturing Directorate, AFRL/MLPSO, Wright-Patterson AFB, OH 45433 (United States); Scripsick, M P [Nova Phase, Newton, NJ 07860 (United States); Edwards, G J [Department of Physics, West Virginia University, Morgantown, WV 26506 (United States); Halliburton, L E [Department of Physics, West Virginia University, Morgantown, WV 26506 (United States)

    2003-06-18

    Electron paramagnetic resonance and electron-nuclear double resonance have been used to characterize four Ti{sup 3+} centres in undoped crystals of potassium titanyl phosphate (KTiOPO{sub 4} or KTP). These 3d{sup 1} defects (S = 1/2) are produced by ionizing radiation (either 60 kV x-rays or 355 nm photons from a tripled Nd:YAG laser), and form when the regular Ti{sup 4+} ions in the crystal trap an electron. Two of these trapped-electron centres are only observed in hydrothermally grown KTP and the other two are dominant in flux-grown KTP. Both of the Ti{sup 3+} centres in hydrothermally grown crystals have a neighbouring proton (i.e. an OH{sup -} molecule). In the flux-grown crystals, one of the Ti{sup 3+} centres is adjacent to an oxygen vacancy and the other centre is tentatively attributed to a self-trapped electron (i.e. a Ti{sup 3+} centre with no stabilizing entity nearby). The g matrix and phosphorus hyperfine matrices are determined for all four Ti{sup 3+} centres, and the proton hyperfine matrix is determined for the two centres associated with OH{sup -} ions. These Ti{sup 3+} centres contribute to the formation of the grey tracks often observed in KTP crystals used to generate the second harmonic of high-power, near-infrared lasers.

  12. Assessment of CCL2 and CXCL8 chemokines in serum, bronchoalveolar lavage fluid and lung tissue samples from dogs affected with canine idiopathic pulmonary fibrosis.

    Science.gov (United States)

    Roels, Elodie; Krafft, Emilie; Farnir, Frederic; Holopainen, Saila; Laurila, Henna P; Rajamäki, Minna M; Day, Michael J; Antoine, Nadine; Pirottin, Dimitri; Clercx, Cecile

    2015-10-01

    Canine idiopathic pulmonary fibrosis (CIPF) is a progressive disease of the lung parenchyma that is more prevalent in dogs of the West Highland white terrier (WHWT) breed. Since the chemokines (C-C motif) ligand 2 (CCL2) and (C-X-C motif) ligand 8 (CXCL8) have been implicated in pulmonary fibrosis in humans, the aim of the present study was to investigate whether these same chemokines are involved in the pathogenesis of CIPF. CCL2 and CXCL8 concentrations were measured by ELISA in serum and bronchoalveolar lavage fluid (BALF) from healthy dogs and WHWTs affected with CIPF. Expression of the genes encoding CCL2 and CXCL8 and their respective receptors, namely (C-C motif) receptor 2 (CCR2) and (C-X-C motif) receptor 2 (CXCR2), was compared in unaffected lung tissue and biopsies from dogs affected with CIPF by quantitative PCR and localisation of CCL2 and CXCL8 proteins were determined by immunohistochemistry. Significantly greater CCL2 and CXCL8 concentrations were found in the BALF from WHWTs affected with CIPF, compared with healthy dogs. Significantly greater serum concentrations of CCL2, but not CXCL8, were found in CIPF-affected dogs compared with healthy WHWTs. No differences in relative gene expression for CCL2, CXCL8, CCR2 or CXCR2 were observed when comparing lung biopsies from control dogs and those affected with CIPF. In affected lung tissues, immunolabelling for CCL2 and CXCL8 was observed in bronchial airway epithelial cells in dogs affected with CIPF. The study findings suggest that both CCL2 and CXCL8 are involved in the pathogenesis of CIPF. Further studies are required to determine whether these chemokines might have a clinical use as biomarkers of fibrosis or as targets for therapeutic intervention. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Chemokine CCL2 and its receptor CCR2 in the medullary dorsal horn are involved in trigeminal neuropathic pain

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    Zhang Zhi-Jun

    2012-07-01

    Full Text Available Abstract Background Neuropathic pain in the trigeminal system is frequently observed in clinic, but the mechanisms involved are largely unknown. In addition, the function of immune cells and related chemicals in the mechanism of pain has been recognized, whereas few studies have addressed the potential role of chemokines in the trigeminal system in chronic pain. The present study was undertaken to test the hypothesis that chemokine C-C motif ligand 2 (CCL2-chemokine C-C motif receptor 2 (CCR2 signaling in the trigeminal nucleus is involved in the maintenance of trigeminal neuropathic pain. Methods The inferior alveolar nerve and mental nerve transection (IAMNT was used to induce trigeminal neuropathic pain. The expression of ATF3, CCL2, glial fibrillary acidic protein (GFAP, and CCR2 were detected by immunofluorescence histochemical staining and western blot. The cellular localization of CCL2 and CCR2 were examined by immunofluorescence double staining. The effect of a selective CCR2 antagonist, RS504393 on pain hypersensitivity was checked by behavioral testing. Results IAMNT induced persistent (>21 days heat hyperalgesia of the orofacial region and ATF3 expression in the mandibular division of the trigeminal ganglion. Meanwhile, CCL2 expression was increased in the medullary dorsal horn (MDH from 3 days to 21 days after IAMNT. The induced CCL2 was colocalized with astroglial marker GFAP, but not with neuronal marker NeuN or microglial marker OX-42. Astrocytes activation was also found in the MDH and it started at 3 days, peaked at 10 days and maintained at 21 days after IAMNT. In addition, CCR2 was upregulated by IAMNT in the ipsilateral medulla and lasted for more than 21 days. CCR2 was mainly colocalized with NeuN and few cells were colocalized with GFAP. Finally, intracisternal injection of CCR2 antagonist, RS504393 (1, 10 μg significantly attenuated IAMNT-induced heat hyperalgesia. Conclusion The data suggest that CCL2-CCR

  14. Plasma Chemokines in Patients with Alcohol Use Disorders: Association of CCL11 (Eotaxin-1) with Psychiatric Comorbidity

    Science.gov (United States)

    García-Marchena, Nuria; Araos, Pedro Fernando; Barrios, Vicente; Sánchez-Marín, Laura; Chowen, Julie A.; Pedraz, María; Castilla-Ortega, Estela; Romero-Sanchiz, Pablo; Ponce, Guillermo; Gavito, Ana L.; Decara, Juan; Silva, Daniel; Torrens, Marta; Argente, Jesús; Rubio, Gabriel; Serrano, Antonia; de Fonseca, Fernando Rodríguez; Pavón, Francisco Javier

    2017-01-01

    Recent studies have linked changes in peripheral chemokine concentrations to the presence of both addictive behaviors and psychiatric disorders. The present study further explore this link by analyzing the potential association of psychiatry comorbidity with alterations in the concentrations of circulating plasma chemokine in patients of both sexes diagnosed with alcohol use disorders (AUD). To this end, 85 abstinent subjects with AUD from an outpatient setting and 55 healthy subjects were evaluated for substance and mental disorders. Plasma samples were obtained to quantify chemokine concentrations [C–C motif (CC), C–X–C motif (CXC), and C–X3–C motif (CX3C) chemokines]. Abstinent AUD patients displayed a high prevalence of comorbid mental disorders (72%) and other substance use disorders (45%). Plasma concentrations of chemokines CXCL12/stromal cell-derived factor-1 (p < 0.001) and CX3CL1/fractalkine (p < 0.05) were lower in AUD patients compared to controls, whereas CCL11/eotaxin-1 concentrations were strongly decreased in female AUD patients (p < 0.001). In the alcohol group, CXCL8 concentrations were increased in patients with liver and pancreas diseases and there was a significant correlation to aspartate transaminase (r = +0.456, p < 0.001) and gamma-glutamyltransferase (r = +0.647, p < 0.001). Focusing on comorbid psychiatric disorders, we distinguish between patients with additional mental disorders (N = 61) and other substance use disorders (N = 38). Only CCL11 concentrations were found to be altered in AUD patients diagnosed with mental disorders (p < 0.01) with a strong main effect of sex. Thus, patients with mood disorders (N = 42) and/or anxiety (N = 16) had lower CCL11 concentrations than non-comorbid patients being more evident in women. The alcohol-induced alterations in circulating chemokines were also explored in preclinical models of alcohol use with male Wistar rats. Rats exposed to

  15. Increase of (CdSe/ZnS)Cys quantum dot luminescence intensity in the presence of TPPS{sub 4} porphyrin

    Energy Technology Data Exchange (ETDEWEB)

    Parra, Gustavo G.; Borissevitch, Iouri E. [Universidade de Sao Paulo (FFCLRP/USP), Ribeirao Preto, SP (Brazil). Fac. de Filosofia, Ciencias e Letras de Ribeirao Preto. Dept. de Fisica; Kuzmin, Vladimir A. [Emanuel Institute of Biophysical Chemistry, RAS-RU, Moscow (Russian Federation); Oleinikov, Vladimir A. [Shemyakin and Ovchinnikov Institute of Biooganic Cemistry, RAS-RU, Moscow (Russian Federation)

    2012-07-01

    Full text: Nanocrystal semiconductor particles or Quantum Dots (QD) possess extraordinary photophysical characteristics, such as extreme high fluorescence quantum yield and optical absorption and very narrow fluorescence band, which can be easily shifted by changing of QD particle size. Due to these characteristics, QD is promising for fluorescence cancer diagnostics and photodynamic treatment. The efficiency of these processes can be in- creased by energy transfer between QD and classic fluorescence probes and photosensitizers (PS). In this work we present on the study of the increase of (CdSe/ZnS)Cys quantum dot luminescence intensity, stimulated by interaction with TPPS{sub 4} porphyrin. The optical absorption and steady-state and time-resolved fluorescence techniques were employed. Water soluble QD (CdSe/ZnS) with emission at 580 nm, functionalized with cysteine (Cys), were studied. TPPS{sub 4} porphyrin was used as a stimulator of QD luminescence. All experiments were realized in PBS buffer (pH 7.3; 7.5 mM) in Milli-Q quality water. The TPPS{sub 4} adding into the QD solutions until the 5{mu}M concentration produced an increase in QD luminescence intensity and lifetime, while for TPPS{sub 4} concentrations higher than 20{mu}M the reduction of the fluorescence intensity was observed, the emission spectra and fluorescence decays profile being unchanged. This effect can not be due to the electrostatic interaction between (CdSe/ZnS)Cys and TPPS{sub 4} because both, (CdSe/ZnS)Cys and TPPS{sub 4}, are negatively charged. We suppose that TPPS{sub 4} porphyrin interacts directly with QD (ZnS) shell, reducing the dangling bound number. This reduction decreases, in turn, the probability of nonradiative ways of the excitation energy dissipation. When the majority of dangling bound is occupied by the TPPS{sub 4} molecules, the effect of QD luminescence reduction (quenching) by porphyrin predominates, probably, via the energy transfer from QD to TPPS{sub 4}. However

  16. DOT for patients with limited access to health care facilities in a hill district of eastern Nepal.

    Science.gov (United States)

    Wares, D F; Akhtar, M; Singh, S

    2001-08-01

    The hill district in Nepal, where access to health care facilities is difficult. To compare results before and after a decentralised directly observed treatment (DOT) intervention. Prospective study of patients registered in Dhankuta district, Nepal, 1996-1999. Patients received their intensive phase treatment under health worker supervision via one of three DOT options: 1) ambulatory from the peripheral government health facilities; 2) ambulatory from an international non-governmental organisation (INGO) TB clinic in district centre; or 3) resident in INGO TB hostel in district centre. Historical data from 1995-1996, with unsupervised short-course chemotherapy, were used for comparison. Of 307 new cases, respectively 126 (41%), 86 (28%) and 95 (31%) took their intensive phase treatment via options 1, 2 and 3. Smear conversion (at 2 months) and cure rates in new smear-positive pulmonary tuberculosis cases were respectively 81.6% (vs. 58.8% historical, P = 0.001) and 84.9% (vs. 76.7% historical, P = 0.03). Overall costs to the INGO provider fell by 7%, mainly as a result of staffing reductions in the INGO services made possible by rationalisation with government services during the intervention. By offering varied DOT delivery routes, including an in-patient option, satisfactory results are possible with DOT even in areas where access to health care facilities is difficult. Provision of in-patient care via an INGO TB hostel allowed a significant proportion of new cases (31%) to receive their intensive phase treatment who otherwise may have had difficulty accessing treatment, due either to the distance to the nearest health facility or to disease severity. Substitution of government hospital beds or local hotel beds for the INGO hostel beds may allow the model to be reproduced elsewhere in similar geographical conditions in Nepal, but further studies should be performed in a non-INGO supported district beforehand.

  17. CCL18: a urinary marker of Gaucher cell burden in Gaucher patients

    NARCIS (Netherlands)

    Boot, Rolf G.; Verhoek, Marri; Langeveld, Mirjam; Renkema, G. Herma; Hollak, Carla E. M.; Weening, Jan J.; Donker-Koopman, Wilma E.; Groener, Johanna E.; Aerts, Johannes M. F. G.

    2006-01-01

    Glucosylceramide-laden tissue macrophages in Gaucher patients secrete large quantities of chitotriosidase and CC chemokine ligand 18 (CCL18), resulting in markedly increased plasma levels. We have comparatively investigated the occurrence of both parameters in plasma and urine samples of Gaucher

  18. Transport in quantum dots

    International Nuclear Information System (INIS)

    Deus, Fernanda; Continetino, Mucio

    2011-01-01

    Full text. In this work we study the time dependent transport in interacting quantum dot. This is a zero-dimensional nano structure system which has quantized electronic states. In our purpose, we are interested in studying such system in a Coulomb blockade regime where a mean-field treatment of the electronic correlations are appropriate. The quantum dot is described by an Anderson type of Hamiltonian where the hybridization term arises from the contact with the leads. We consider a time dependence of both the energy of the localized state in the quantum dot and of the hybridization-like term. These time dependent parameters, under certain conditions, induce a current in the quantum dot even in the absence of difference on the chemical potential of the leads. The approach to this non-equilibrium problem requires the use of a Keldysh formalism. We calculate the non- equilibrium Green's functions and obtain results for the average (equilibrium term) and the non-equilibrium values of the electronic occupation number in the dot. we consider the possibility of a magnetic solution, with different values for the average up and down spins in the quantum dot. Our results allow to obtain, for instance, the tunneling current through the dot. The magnetic nature of the dot, for a certain range of parameters should give rise also to an induced spin current through the dot

  19. Synthesis of colloidal SnSe quantum dots by electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Li Zhen; Peng Liwei; Fang Yaoguo; Chen Zhiwen [Shanghai Applied Radiation Institute, Shanghai University, Shanghai 201800 (China); Pan Dengyu [Institute of Nanochemistry and Nanobiology, Shanghai University, Shanghai 201800 (China); Wu Minghong, E-mail: mhwu@staff.shu.edu.cn [Shanghai Applied Radiation Institute, Shanghai University, Shanghai 201800 (China)

    2011-12-15

    Water-soluble orthorhombic colloidal SnSe quantum dots with an average diameter of 4 nm were successfully prepared by a novel irradiation route using an electronic accelerator as a radiation source and hexadecyl trimethyl ammonium bromide (CTAB) as a surfactant. The quantum dots exhibit a large direct bandgap of 3.89 eV, greatly blue shifted compared with that of bulk SnSe (1.0 eV) due to the quantum confinement effect. The quantum dots show blue photoluminescence at {approx}420 nm. The influence of CTAB on the growth of the quantum dots was investigated and a possible reaction/growth mechanism was proposed. - Highlights: > A rapid, facile and green strategy is developed to synthesize SnSe QDs. > The raw materials are green and easily obtained. > The surfactant CTAB plays an important role in the formation of SnSe quantum dots. > The obtained SnSe QDs is well-dispersed with the average size of around 4 nm.

  20. EPR study of Gd sup 3 sup + centres in Tl sub 2 ZnF sub 4 crystals

    CERN Document Server

    Arakawa, M; Ebisu, H; Takeuchi, H

    2003-01-01

    EPR measurements have been made at room temperature on Tl sub 2 ZnF sub 4 crystals doped with Gd sup 3 sup + and co-doped with Gd sup 3 sup + and Li sup +. For crystals doped only with Gd sup 3 sup + , a spectrum with tetragonal symmetry (A centre) is observed. For co-doped crystals new spectra with tetragonal (B centre) and monoclinic (C centre) symmetries are observed in place of the spectrum of the A centre. The A centre is identified as the substitutional Gd sup 3 sup + ion at a Zn sup 2 sup + site in six-fold coordination without any local charge compensation in its immediate neighbourhood. On the basis of spin Hamiltonian separation analysis, the separated parameter b sub 2 sub a sub ( sub 1 sub ) for the C centre has a value close to the b sub 2 sup 0 parameter for the B centre. The B and C centres in co-doped crystals are ascribed to a Gd sup 3 sup + ion substituted for a Tl sup + site in nine-fold coordination, where the divalent excess positive charge on Gd sup 3 sup + is compensated by a Li sup + i...

  1. Simulation of quantum dots size and spacing effect for intermediate band solar cell application based on InAs quantum dots arrangement in GaAs

    Energy Technology Data Exchange (ETDEWEB)

    Hendra, P. I. B., E-mail: ib.hendra@gmail.com; Rahayu, F., E-mail: ib.hendra@gmail.com; Darma, Y., E-mail: ib.hendra@gmail.com [Physical Vapor Deposition Laboratory, Physics of Material Electronics Research, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132 (Indonesia)

    2014-03-24

    Intermediate band solar cell (IBSC) has become a promising technology in increasing solar cell efficiency. In this work we compare absorption coefficient profile between InAs quantum dots with GaAs bulk. We calculate the efficiency of GaAs bulk and GaAs doped with 2, 5, and 10 nm InAs quantum dot. Effective distances in quantum dot arrangement based on electron tunneling consideration were also calculated. We presented a simple calculation method with low computing power demand. Results showed that arrangement of quantum dot InAs in GaAs can increase solar cell efficiency from 23.9 % initially up to 60.4%. The effective distance between two quantum dots was found 2 nm in order to give adequate distance to prevent electron tunneling and wave functions overlap.

  2. Modeling of the quantum dot filling and the dark current of quantum dot infrared photodetectors

    International Nuclear Information System (INIS)

    Ameen, Tarek A.; El-Batawy, Yasser M.; Abouelsaood, A. A.

    2014-01-01

    A generalized drift-diffusion model for the calculation of both the quantum dot filling profile and the dark current of quantum dot infrared photodetectors is proposed. The confined electrons inside the quantum dots produce a space-charge potential barrier between the two contacts, which controls the quantum dot filling and limits the dark current in the device. The results of the model reasonably agree with a published experimental work. It is found that increasing either the doping level or the temperature results in an exponential increase of the dark current. The quantum dot filling turns out to be nonuniform, with a dot near the contacts containing more electrons than one in the middle of the device where the dot occupation approximately equals the number of doping atoms per dot, which means that quantum dots away from contacts will be nearly unoccupied if the active region is undoped

  3. Presence of photoluminescent carbon dots in Nescafe® original instant coffee: applications to bioimaging.

    Science.gov (United States)

    Jiang, Chengkun; Wu, Hao; Song, Xiaojie; Ma, Xiaojun; Wang, Jihui; Tan, Mingqian

    2014-09-01

    The presence of the carbon dots (C-dots) in food is a hotly debated topic and our knowledge about the presence and the use of carbon dots (C-dots) in food is still in its infancy. We report the finding of the presence of photoluminescent (PL) C-dots in commercial Nescafe instant coffee. TEM analysis reveals that the extracted C-dots have an average size of 4.4 nm. They were well-dispersed in water and strongly photoluminescent under the excitation of ultra-violet light with a quantum yield (QY) about 5.5%, which were also found to possess clear upconversion PL properties. X-ray photoelectron spectroscopy characterization demonstrates that the C-dots contain C, O and N three elements with the relative contents ca. 30.1, 62.2 and 7.8%. The X-ray diffraction (XRD) analysis indicates that the C-dots are amorphous. Fourier-transform infrared (FTIR) spectra were employed to characterize the surface groups of the C-dots. The C-dots show a pH independent behavior by varying the pH value from 2 to 11. The cytotoxicity study revealed that the C-dots did not cause any toxicity to cells at a concentration as high as 20 mg/mL. The C-dots have been directly applied in cells and fish imaging, which suggested that the C-dots present in commercial coffee may have more potential biological applications. Copyright © 2014. Published by Elsevier B.V.

  4. Effects of undenatured whey protein supplementation on CXCL12- and CCL21-mediated B and T cell chemotaxis in diabetic mice

    Directory of Open Access Journals (Sweden)

    Badr Gamal

    2011-11-01

    Full Text Available Abstract Background Long and persistent uncontrolled diabetes tends to degenerate the immune system and leads to an increased incidence of infection. Whey proteins (WPs enhance immunity during early life and have a protective role in some immune disorders. In this study, the effects of camel WP on the chemotaxis of B and T cells to CXCL12 and CCL21 in diabetic mice were investigated. Results Flow cytometric analysis of the surface expressions of CXCR4 (CXCL12 receptor and CCR7 (CCL21 receptor on B and T cells revealed that the surface expressions of CXCR4 and CCR7 were not significantly altered in diabetic and WP-supplemented diabetic mice compared with control mice. Nevertheless, B and T lymphocytes from diabetic mice were found to be in a stunned state, with a marked and significant (P Conclusion Our data revealed the benefits of WP supplementation in enhancing cytoskeletal rearrangement and chemotaxis in B and T cells, and subsequently improving the immune response in diabetic mice.

  5. Costs and cost-effectiveness of different DOT strategies for the treatment of tuberculosis in Pakistan. Directly Observed Treatment.

    Science.gov (United States)

    Khan, M A; Walley, J D; Witter, S N; Imran, A; Safdar, N

    2002-06-01

    An economic study was conducted alongside a clinical trial at three sites in Pakistan to establish the costs and effectiveness of different strategies for implementing directly observed treatment (DOT) for tuberculosis. Patients were randomly allocated to one of three arms: DOTS with direct observation by health workers (at health centres or by community health workers); DOTS with direct observation by family members; and DOTS without direct observation. The clinical trial found no statistically significant difference in cure rate for the different arms. The economic study collected data on the full range of health service costs and patient costs of the different treatment arms. Data were also disaggregated by gender, rural and urban patients, by treatment site and by economic categories, to investigate the costs of the different strategies, their cost-effectiveness and the impact that they might have on patient compliance with treatment. The study found that direct observation by health centre-based health workers was the least cost-effective of the strategies tested (US dollars 310 per case cured). This is an interesting result, as this is the model recommended by the World Health Organization and International Union against Tuberculosis and Lung Disease. Attending health centres daily during the first 2 months generated high patient costs (direct and in terms of time lost), yet cure rates for this group fell below those of the non-observed group (58%, compared with 62%). One factor suggested by this study is that the high costs of attending may be deterring patients, and in particular, economically active patients who have most to lose from the time taken by direct observation. Without stronger evidence of benefits, it is hard to justify the costs to health services and patients that this type of direct observation imposes. The self-administered group came out as most cost-effective (164 dollars per case cured). The community health worker sub-group achieved the

  6. Internalization of targeted quantum dots by brain capillary endothelial cells in vivo.

    Science.gov (United States)

    Paris-Robidas, Sarah; Brouard, Danny; Emond, Vincent; Parent, Martin; Calon, Frédéric

    2016-04-01

    Receptors located on brain capillary endothelial cells forming the blood-brain barrier are the target of most brain drug delivery approaches. Yet, direct subcellular evidence of vectorized transport of nanoformulations into the brain is lacking. To resolve this question, quantum dots were conjugated to monoclonal antibodies (Ri7) targeting the murine transferrin receptor. Specific transferrin receptor-mediated endocytosis of Ri7-quantum dots was first confirmed in N2A and bEnd5 cells. After intravenous injection in mice, Ri7-quantum dots exhibited a fourfold higher volume of distribution in brain tissues, compared to controls. Immunofluorescence analysis showed that Ri7-quantum dots were sequestered throughout the cerebral vasculature 30 min, 1 h, and 4 h post injection, with a decline of signal intensity after 24 h. Transmission electron microscopic studies confirmed that Ri7-quantum dots were massively internalized by brain capillary endothelial cells, averaging 37 ± 4 Ri7-quantum dots/cell 1 h after injection. Most quantum dots within brain capillary endothelial cells were observed in small vesicles (58%), with a smaller proportion detected in tubular structures or in multivesicular bodies. Parenchymal penetration of Ri7-quantum dots was extremely low and comparable to control IgG. Our results show that systemically administered Ri7-quantum dots complexes undergo extensive endocytosis by brain capillary endothelial cells and open the door for novel therapeutic approaches based on brain endothelial cell drug delivery. © The Author(s) 2015.

  7. The Coxiella Burnetii type IVB secretion system (T4BSS) component DotA is released/secreted during infection of host cells and during in vitro growth in a T4BSS-dependent manner.

    Science.gov (United States)

    Luedtke, Brandon E; Mahapatra, Saugata; Lutter, Erika I; Shaw, Edward I

    2017-06-01

    Coxiella burnetii is a Gram-negative intracellular pathogen and is the causative agent of the zoonotic disease Q fever. To cause disease, C. burnetii requires a functional type IVB secretion system (T4BSS) to transfer effector proteins required for the establishment and maintenance of a membrane-bound parasitophorous vacuole (PV) and further modulation of host cell process. However, it is not clear how the T4BSS interacts with the PV membrane since neither a secretion pilus nor an extracellular pore forming apparatus has not been described. To address this, we used the acidified citrate cysteine medium (ACCM) along with cell culture infection and immunological techniques to identify the cellular and extracellular localization of T4BSS components. Interestingly, we found that DotA and IcmX were secreted/released in a T4BSS-dependent manner into the ACCM. Analysis of C. burnetii-infected cell lines revealed that DotA colocalized with the host cell marker CD63 (LAMP3) at the PV membrane. In the absence of bacterial protein synthesis, DotA also became depleted from the PV membrane. These data are the first to identify the release/secretion of C. burnetii T4BSS components during axenic growth and the interaction of a T4BSS component with the PV membrane during infection of host cells. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  8. DOT's CAFE rulemaking analysis.

    Science.gov (United States)

    2013-02-13

    Presentation discusses what DOT needs to consider in setting CAFE standards. How DOT's use of the CAFE Compliance and Effects Modeling System helps to analyze potential CAFE Standards. How DOT might approach the next round of CAFE standards for model...

  9. [Louis Braille (1809-1852)--inventor of raised dots system].

    Science.gov (United States)

    Maciejewicz, Piotr; Kopacz, Dorota

    2005-01-01

    Louis Braille was born on January 4th 1809 in Coupvray, France. An injury to his eye at the age of three, resulted in total loss of vision. In 1819 he entered the Institute for Blind Youth in Paris. There he would live, study, and later teach. When he was fifteen, he developed system of reading and writing by means of raised dots, which is known today as Braille. The basis of the Braille system is known as a Braille cell. The cell is comprised of six dots numbered in a specific order. Each dot or combination of dots represents a letter of the alphabet. This Braille system has established itself internationally and formed the basic Braille for all languages.

  10. Inhibition of human immunodeficiency virus replication by a dual CCR5/CXCR4 antagonist

    DEFF Research Database (Denmark)

    Princen, Katrien; Hatse, Sigrid; Vermeire, Kurt

    2004-01-01

    Here we report that the N-pyridinylmethyl cyclam analog AMD3451 has antiviral activity against a wide variety of R5, R5/X4, and X4 strains of human immunodeficiency virus type 1 (HIV-1) and HIV-2 (50% inhibitory concentration [IC(50)] ranging from 1.2 to 26.5 microM) in various T-cell lines, CCR5...... at the virus entry stage. AMD3451 dose-dependently inhibited the intracellular Ca(2+) signaling induced by the CXCR4 ligand CXCL12 in T-lymphocytic cells and in CXCR4-transfected cells, as well as the Ca(2+) flux induced by the CCR5 ligands CCL5, CCL3, and CCL4 in CCR5-transfected cells. The compound did...... not interfere with chemokine-induced Ca(2+) signaling through CCR1, CCR2, CCR3, CCR4, CCR6, CCR9, or CXCR3 and did not induce intracellular Ca(2+) signaling by itself at concentrations up to 400 microM. In freshly isolated monocytes, AMD3451 inhibited the Ca(2+) flux induced by CXCL12 and CCL4...

  11. The positive correlation of the CCL2-CCR2 axis with the disease activity may indicate the fundamental role in the pathogenesis of oral lichen planus.

    Science.gov (United States)

    Yin, Jingfang; Yang, Xi; Zeng, Qi; Yang, Linglan; Cheng, Bin; Tao, Xiaoan

    2016-01-01

    The important roles of CCL2 and its receptor CCR2 had been reported in a series of inflammatory disorders. However, few studies investigated the potential role of CCL2/CCR2 axis in oral lichen planus (OLP). Therefore, this study aimed to detect the expression of CCL2 and CCR2 in OLP lesions and compare their changes before and after treatment. CCL2 and CCR2 expression was investigated using immunohistochemical staining and real-time RT-PCR in 32 patients with OLP and eight controls. Moreover, changes in their expression after treatment with triamcinolone acetonide were assessed in lesions from three patients. CCL2+ and CCR2+ cells were few in the controls and remarkably increased in the epithelial and subepithelial layers of lesions (n = 32, all P < 0.001). However, the densities of CCL2+ and CCR2+ cells were not significantly different between reticular (n = 12) and erythematous/erosive lesions (n = 20), although they significantly decreased after treatment (627.7 ± 108.2 vs. 258.3 ± 148.3, P = 0.017; 1034.7 ± 74.6 vs. 648 ± 77.6, P = 0.003, respectively). CCL2+/CCR2+ cell numbers were positively correlated with disease activity (correlation coefficient, 0.588; P < 0.001; correlation coefficient, 0.409; P = 0.02, respectively). The results of this study indicated that the CCL2-CCR2 axis was involved in the pathogenesis of OLP and was positively correlated with disease activity. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. TRPV1 receptor inhibition decreases CCL2-induced hyperalgesia

    Czech Academy of Sciences Publication Activity Database

    Špicarová, Diana; Adámek, Pavel; Kalynovska, Nataliia; Mrózková, Petra; Paleček, Jiří

    2014-01-01

    Roč. 81, JUN (2014), s. 75-84 ISSN 0028-3908 R&D Projects: GA ČR(CZ) GA305/09/1228; GA ČR(CZ) GPP303/12/P510; GA ČR(CZ) GBP304/12/G069; GA MŠk(CZ) LH12058 Grant - others:Univerzita Karlova(CZ) 253154 Institutional support: RVO:67985823 Keywords : pain * spinal cord * synaptic transmission * CCL2 * TRPV1 * EPSC Subject RIV: FH - Neurology Impact factor: 5.106, year: 2014

  13. Regulation of CCL2 expression by an upstream TALE homeodomain protein-binding site that synergizes with the site created by the A-2578G SNP.

    Science.gov (United States)

    Page, Stephen H; Wright, Edward K; Gama, Lucio; Clements, Janice E

    2011-01-01

    CC Chemokine Ligand 2 (CCL2) is a potent chemoattractant produced by macrophages and activated astrocytes during periods of inflammation within the central nervous system. Increased CCL2 expression is correlated with disease progression and severity, as observed in pulmonary tuberculosis, HCV-related liver disease, and HIV-associated dementia. The CCL2 distal promoter contains an A/G polymorphism at position -2578 and the homozygous -2578 G/G genotype is associated with increased CCL2 production and inflammation. However, the mechanisms that contribute to the phenotypic differences in CCL2 expression are poorly understood. We previously demonstrated that the -2578 G polymorphism creates a TALE homeodomain protein binding site (TALE binding site) for PREP1/PBX2 transcription factors. In this study, we identified the presence of an additional TALE binding site 22 bp upstream of the site created by the -2578 G polymorphism and demonstrated the synergistic effects of the two sites on the activation of the CCL2 promoter. Using chromatin immunoprecipitation (ChIP) assays, we demonstrated increased binding of the TALE proteins PREP1 and PBX2 to the -2578 G allele, and binding of IRF1 to both the A and G alleles. The presence of TALE binding sites that form inverted repeats within the -2578 G allele results in increased transcriptional activation of the CCL2 distal promoter while the presence of only the upstream TALE binding site within the -2578 A allele exerts repression of promoter activity.

  14. Theoretical investigations on the defect structures and spin Hamiltonian parameters for various orthorhombic Rh{sup 2+} centres in KTiOPO{sub 4} and KTiOAsO{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Chang-Chun, E-mail: ccding626@163.com; Wu, Shao-Yi, E-mail: wushaoyi@uestc.edu.cn; Zhang, Li-Juan; Li, Guo-Liang; Zhang, Zhi-Hong

    2015-12-15

    The defect structures and spin Hamiltonian parameters (SHPs) for three Rh{sup 2+} centres (denoted C{sub 1} in KTiOAsO{sub 4} and C{sub 2} and C{sub 3} in KTiOPO{sub 4}) are theoretically investigated by utilising the perturbation formulae for a 4d{sup 7} ion under orthorhombically (D{sub 2h}) elongated octahedra. The defect structures are characterized by the axial elongation ratios of 4.91%, 4.93% and 4.90% along the Z axis and the planar bond length variation ratios of 0.05%, 0.01% and 0.04% for centres C{sub 1}, C{sub 2} and C{sub 3}, respectively, owing to the Jahn–Teller effect. The nearly identical moderate axial elongation ratios and the slightly different tiny planar bond length variation ratios may suitably account for the comparable moderate axial g anisotropies ∆g (≈0.6087, 0.6124 and 0.6067) and the slightly dissimilar tiny perpendicular g anisotropies δg (≈0.0649, 0.0097 and 0.0509) of the three centres, respectively. All centres demonstrate similar strong crystal-field interactions and moderate covalence arising from the comparable short impurity-ligand distances.

  15. Short-wavelength InAlGaAs/AlGaAs quantum dot superluminescent diodes

    Science.gov (United States)

    Liang, De-Chun; An, Qi; Jin, Peng; Li, Xin-Kun; Wei, Heng; Wu, Ju; Wang, Zhan-Guo

    2011-10-01

    This paper reports the fabrication of J-shaped bent-waveguide superluminescent diodes utilizing an InAlGaAs/AlGaAs quantum dot active region. The emission spectrum of the device is centred at 884 nm with a full width at half maximum of 37 nm and an output power of 18 mW. By incorporating an Al composition into the quantum dot active region, short-wavelength superluminescent diode devices can be obtained. An intersection was found for the light power-injection current curves measured from the straight-waveguide facet and the bent-waveguide facet, respectively. The result is attributed to the conjunct effects of the gain and the additional loss of the bent waveguide. A numerical simulation is performed to verify the qualitative explanation. It is shown that bent waveguide loss is an important factor that affects the output power of J-shaped superluminescent diode devices.

  16. Models of mass segregation at the Galactic Centre

    International Nuclear Information System (INIS)

    Freitag, Marc; Amaro-Seoane, Pau; Kalogera, Vassiliki

    2006-01-01

    We study the process of mass segregation through 2-body relaxation in galactic nuclei with a central massive black hole (MBH). This study has bearing on a variety of astrophysical questions, from the distribution of X-ray binaries at the Galactic centre, to tidal disruptions of main- sequence and giant stars, to inspirals of compact objects into the MBH, an important category of events for the future space borne gravitational wave interferometer LISA. In relatively small galactic nuclei, typical hosts of MBHs with masses in the range 10 4 - 10 7 M o-dot , the relaxation induces the formation of a steep density cusp around the MBH and strong mass segregation. Using a spherical stellar dynamical Monte-Carlo code, we simulate the long-term relaxational evolution of galactic nucleus models with a spectrum of stellar masses. Our focus is the concentration of stellar black holes to the immediate vicinity of the MBH. Special attention is given to models developed to match the conditions in the Milky Way nucleus

  17. Electron paramagnetic resonance and electron-nuclear double-resonance study of Ti sup 3 sup + centres in KTiOPO sub 4

    CERN Document Server

    Setzler, S D; Fernelius, N C; Scripsick, M P; Edwards, G J; Halliburton, L E

    2003-01-01

    Electron paramagnetic resonance and electron-nuclear double resonance have been used to characterize four Ti sup 3 sup + centres in undoped crystals of potassium titanyl phosphate (KTiOPO sub 4 or KTP). These 3d sup 1 defects (S = 1/2) are produced by ionizing radiation (either 60 kV x-rays or 355 nm photons from a tripled Nd:YAG laser), and form when the regular Ti sup 4 sup + ions in the crystal trap an electron. Two of these trapped-electron centres are only observed in hydrothermally grown KTP and the other two are dominant in flux-grown KTP. Both of the Ti sup 3 sup + centres in hydrothermally grown crystals have a neighbouring proton (i.e. an OH sup - molecule). In the flux-grown crystals, one of the Ti sup 3 sup + centres is adjacent to an oxygen vacancy and the other centre is tentatively attributed to a self-trapped electron (i.e. a Ti sup 3 sup + centre with no stabilizing entity nearby). The g matrix and phosphorus hyperfine matrices are determined for all four Ti sup 3 sup + centres, and the proto...

  18. Phonon impact on optical control schemes of quantum dots: Role of quantum dot geometry and symmetry

    Science.gov (United States)

    Lüker, S.; Kuhn, T.; Reiter, D. E.

    2017-12-01

    Phonons strongly influence the optical control of semiconductor quantum dots. When modeling the electron-phonon interaction in several theoretical approaches, the quantum dot geometry is approximated by a spherical structure, though typical self-assembled quantum dots are strongly lens-shaped. By explicitly comparing simulations of a spherical and a lens-shaped dot using a well-established correlation expansion approach, we show that, indeed, lens-shaped dots can be exactly mapped to a spherical geometry when studying the phonon influence on the electronic system. We also give a recipe to reproduce spectral densities from more involved dots by rather simple spherical models. On the other hand, breaking the spherical symmetry has a pronounced impact on the spatiotemporal properties of the phonon dynamics. As an example we show that for a lens-shaped quantum dot, the phonon emission is strongly concentrated along the direction of the smallest axis of the dot, which is important for the use of phonons for the communication between different dots.

  19. L-Cysteine Capped CdSe Quantum Dots Synthesized by Photochemical Route.

    Science.gov (United States)

    Singh, Avinash; Kunwar, Amit; Rath, M C

    2018-05-01

    L-cysteine capped CdSe quantum dots were synthesized via photochemical route in aqueous solution under UV photo-irradiation. The as grown CdSe quantum dots exhibit broad fluorescence at room temperature. The CdSe quantum dots were found to be formed only through the reactions of the precursors, i.e., Cd(NH3)2+4 and SeSO2-3 with the photochemically generated 1-hydroxy-2-propyl radicals, (CH3)2COH radicals, which are formed through the process of H atom abstraction by the photoexcited acetone from 2-propanol. L-Cysteine was found to act as a suitable capping agent for the CdSe quantum dots and increases their biocompatability. Cytotoxicty effects of these quantum dots were evaluated in Chinese Hamster Ovary (CHO) epithelial cells, indicated a significant lower level for the L-cysteine capped CdSe quantum dots as compare to the bare ones.

  20. Studies of quantum dots in the quantum Hall regime

    Science.gov (United States)

    Goldmann, Eyal

    We present two studies of quantum dots in the quantum Hall regime. In the first study, presented in Chapter 3, we investigate the edge reconstruction phenomenon believed to occur when the quantum dot filling fraction is n≲1 . Our approach involves the examination of large dots (≤40 electrons) using a partial diagonalization technique in which the occupancies of the deep interior orbitals are frozen. To interpret the results of this calculation, we evaluate the overlap between the diagonalized ground state and a set of trial wavefunctions which we call projected necklace (PN) states. A PN state is simply the angular momentum projection of a maximum density droplet surrounded by a ring of localized electrons. Our calculations reveal that PN states have up to 99% overlap with the diagonalized ground states, and are lower in energy than the states identified in Chamon and Wen's study of the edge reconstruction. In the second study, presented in Chapter 4, we investigate quantum dots in the fractional quantum Hall regime using a Hartree formulation of composite fermion theory. We find that under appropriate conditions, the chemical potential of the dots oscillates periodically with B due to the transfer of composite fermions between quasi-Landau bands. This effect is analogous the addition spectrum oscillations which occur in quantum dots in the integer quantum Hall regime. Period f0 oscillations are found in sharply confined dots with filling factors nu = 2/5 and nu = 2/3. Period 3 f0 oscillations are found in a parabolically confined nu = 2/5 dot. More generally, we argue that the oscillation period of dots with band pinning should vary continuously with B, whereas the period of dots without band pinning is f0 .

  1. CCR3 expression induced by IL-2 and IL-4 functioning as a death receptor for B cells

    DEFF Research Database (Denmark)

    Jinquan, Tan; Jacobi, Henrik H; Jing, Chen

    2003-01-01

    We report that CCR3 is not expressed on freshly isolated peripheral and germinal B cells, but is up-regulated after stimulation with IL-2 and IL-4 (approximately 98% CCR3(+)). Ligation of CCR3 by eotaxin/chemokine ligand (CCL) 11 induces apoptosis in IL-2- and IL-4-stimulated primary CD19......-4, and eotaxin/CCL11 (88% CD95 and 84% CD95L). We therefore propose that ligation of such newly induced CCR3 on peripheral and germinal B cells by eotaxin/CCL11 leads to the enhanced levels of CD95 and CD95L expression. Ligation of CD95 by its CD95L expressed on neigboring B cells triggers relevant....... Interaction between CCR3 and eotaxin/CCL11 may, besides promoting allergic reactions, drive activated B cells to apoptosis, thereby reducing levels of Ig production, including IgE, and consequently limit the development of the humoral immune response. The apoptotic action of eotaxin/CCL11 suggests...

  2. Analysis of the antimicrobial activities of a chemokine-derived peptide (CDAP-4) on Pseudomonas aeruginosa

    International Nuclear Information System (INIS)

    Martinez-Becerra, Francisco; Silva, Daniel-Adriano; Dominguez-Ramirez, Lenin; Mendoza-Hernandez, Guillermo; Lopez-Vidal, Yolanda; Soldevila, Gloria; Garcia-Zepeda, Eduardo A.

    2007-01-01

    Chemokines are key molecules involved in the control of leukocyte trafficking. Recently, a novel function as antimicrobial proteins has been described. CCL13 is the only member of the MCP chemokine subfamily displaying antimicrobial activity. To determine Key residues involved in its antimicrobial activity, CCL13 derived peptides were synthesized and tested against several bacterial strains, including Pseudomonas aeruginosa. One of these peptides, corresponding to the C-terminal region of CCL13 (CDAP-4) displayed good antimicrobial activity. Electron microscopy studies revealed remarkable morphological changes after CDAP-4 treatment. By computer modeling, CDAP-4 in α helical configuration generated a positive electrostatic potential that extended beyond the surface of the molecule. This feature is similar to other antimicrobial peptides. Altogether, these findings indicate that the antimicrobial activity was displayed by CCL13 resides to some extent at the C-terminal region. Furthermore, CDAP-4 could be considered a good antimicrobial candidate with a potential use against pathogens including P. aeruginosa

  3. Next steps towards a Climate Innovation Centre in Ghana. Discussion Paper

    International Nuclear Information System (INIS)

    De Coninck, H.C.; Wuertenberger, L.; Akon-Yamga, G.

    2011-03-01

    A climate innovation centre is an institution aimed at enabling development through catalysing climate technology research, development, market creation and policy. This discussion paper discusses the possibilities, considerations and next steps for a Climate Innovation Centre (CIC) in Ghana based on new insights within the government of Ghana, a mapping of climate innovation in Ghana, new developments in the international climate negotiations and other multilateral processes, and analysis conducted by ECN. The conclusion is that a Climate Innovation Centre can fill significant gaps in climate resilient development in Ghana. It seems important that a Ghana CIC does not become yet another institution that focuses on basic research in the area of climate change. Rather, it should connect the dots of the Ghanaian climate innovation system and act as a knowledge facilitator, also for the private sector. Various models of climate innovation centres exist. Before choices are made for a model or a combination of models for Ghana, it is recommended to allow for a broad stakeholder process. The World Bank's infoDev programme could be a model for such a process. Such stakeholder engagement should be aligned with other policymaking processes on adaptation and low-carbon development, as well as related policy arenas, such as agriculture, transport, waste and energy.

  4. Next steps towards a Climate Innovation Centre in Ghana. Discussion Paper

    Energy Technology Data Exchange (ETDEWEB)

    De Coninck, H.C.; Wuertenberger, L. [ECN Policy Studies, Petten (Netherlands); Akon-Yamga, G. [Science and Technology Policy Research Institute STEPRI, Accra (Guinea)

    2011-03-15

    A climate innovation centre is an institution aimed at enabling development through catalysing climate technology research, development, market creation and policy. This discussion paper discusses the possibilities, considerations and next steps for a Climate Innovation Centre (CIC) in Ghana based on new insights within the government of Ghana, a mapping of climate innovation in Ghana, new developments in the international climate negotiations and other multilateral processes, and analysis conducted by ECN. The conclusion is that a Climate Innovation Centre can fill significant gaps in climate resilient development in Ghana. It seems important that a Ghana CIC does not become yet another institution that focuses on basic research in the area of climate change. Rather, it should connect the dots of the Ghanaian climate innovation system and act as a knowledge facilitator, also for the private sector. Various models of climate innovation centres exist. Before choices are made for a model or a combination of models for Ghana, it is recommended to allow for a broad stakeholder process. The World Bank's infoDev programme could be a model for such a process. Such stakeholder engagement should be aligned with other policymaking processes on adaptation and low-carbon development, as well as related policy arenas, such as agriculture, transport, waste and energy.

  5. Organic-inorganic hybrid carbon dots for cell imaging

    Science.gov (United States)

    Liu, Huan; Zhang, Hongwen; Li, Jiayu; Tang, Yuying; Cao, Yu; Jiang, Yan

    2018-04-01

    In this paper, nitrogen-doped carbon dots (CDs) had been synthesized directly by one-step ultrasonic treatment under mild conditions. During the functionalization process, Octa-aminopropyl polyhedral oligomeric silsesquioxane hydrochloride salt (OA-POSS) was used as stabilizing and passivation agent, which lead to self-assembling of CDs in aqueous medium solution. OA-POSS was obtained via hydrolytic condensation of γ-aminopropyl triethoxy silane (APTES). The average size of CDs prepared was approximately 3.3 nm with distribution between 2.5 nm and 4.5 nm. The prepared organic-inorganic hybrid carbon dots have several characteristics such as photoluminescence emission wavelength, efficient cellular uptake, and good biocompatibility. The results indicate that OA-POSS can maintain the fluorescence properties of the carbon dots effectively, and reduced cytotoxicity provides the possibility for biomedical applications. More than 89% of the Hela cells were viable when incubated with 2 mg ml‑1 or lesser organic-inorganic hybrid carbon dots. Thus, it provides a potential for multicolor imaging with HeLa cells.

  6. Functional role of CCL5/RANTES for HCC progression during chronic liver disease

    NARCIS (Netherlands)

    Mohs, Antje; Kuttkat, Nadine; Reissing, Johanna; Zimmermann, Henning Wolfgang; Sonntag, Roland; Proudfoot, Amanda; Youssef, Sameh A.; de Bruin, Alain; Cubero, Francisco Javier; Trautwein, Christian

    Background & Aims: During liver inflammation, triggering fibrogenesis and carcinogenesis immune cells play a pivotal role. In the present study we investigated the role of CCL5 in human and in murine models of chronic liver inflammation leading to hepatocellular carcinoma (HCC) development. Methods:

  7. The interaction between d-dot's

    International Nuclear Information System (INIS)

    Hirayama, Masaki; Machida, Masahiko; Koyama, Tomio; Ishida, Takekazu; Kato, Masaru

    2005-01-01

    We investigated the interaction between two square d-dot's. The d-dot is the nano-scaled superconducting composite structure that is made of a d-wave superconducting dot embedded in the s-wave superconducting matrix. In the numerical calculation, using the finite element method, we solved the two-components Ginzburg-Landau equation self-consistently. We obtained two kinds of solutions, which can be considered as ferromagnetic and antiferromagnetic configurations, when two d-dot's are separated parallel and diagonally. Also we discuss the applicability of d-dot's as an artificial spin system where the interactions can be controlled by the fabrication

  8. Electroluminescence of colloidal ZnSe quantum dots

    International Nuclear Information System (INIS)

    Dey, S.C.; Nath, S.S.

    2011-01-01

    The article reports a green chemical synthesis of colloidal ZnSe quantum dots at a moderate temperature. The prepared colloid sample is characterised by UV-vis absorption spectroscopy and transmission electron microscopy. UV-vis spectroscopy reveals as-expected blue-shift with strong absorption edge at 400 nm and micrographs show a non-uniform size distribution of ZnSe quantum dots in the range 1-4 nm. Further, photoluminescence and electroluminescence spectroscopies are carried out to study optical emission. Each of the spectroscopies reveals two emission peaks, indicating band-to-band transition and defect related transition. From the luminescence studies, it can be inferred that the recombination of electrons and holes resulting from interband transition causes violet emission and the recombination of a photon generated hole with a charged state of Zn-vacancy gives blue emission. Meanwhile electroluminescence study suggests the application of ZnSe quantum dots as an efficient light emitting device with the advantage of colour tuning (violet-blue-violet). - Highlights: → Synthesis of ZnSe quantum dots by a green chemical route. → Characterisation: UV-vis absorption spectroscopy and transmission electron microscopy. → Analysis of UV-vis absorption spectrum and transmission electron micrographs. → Study of electro-optical properties by photoluminescence and electroluminescence. → Conclusion: ZnSe quantum dots can be used as LED with dual colour emission.

  9. Preparation of carbon quantum dots based high photostability luminescent membranes.

    Science.gov (United States)

    Zhao, Jinxing; Liu, Cui; Li, Yunchuan; Liang, Jiyuan; Liu, Jiyan; Qian, Tonghui; Ding, Jianjun; Cao, Yuan-Cheng

    2017-06-01

    Urethane acrylate (UA) was used to prepare carbon quantum dots (C-dots) luminescent membranes and the resultants were examined with FT-IR, mechanical strength, scanning electron microscope (SEM) and quantum yields (QYs). FT-IR results showed the polyurethane acrylate (PUA) prepolymer -C = C-vibration at 1101 cm -1 disappeared but there was strong vibration at1687cm -1 which was contributed from the-C = O groups in cross-linking PUA. Mechanical strength results showed that the different quantity of C-dots loadings and UV-curing time affect the strength. SEM observations on the cross-sections of the membranes are uniform and have no structural defects, which prove that the C-dots are compatible with the water-soluble PUA resin. The C-dot loading was increased from 0 to 1 g, the maximum tensile stress was nearly 2.67 MPa, but the tensile strain was decreased from 23.4% to 15.1% and 7.2% respectively. QYs results showed that the C-dots in the membrane were stable after 120 h continuous irradiation. Therefore, the C-dots photoluminescent film is the promising material for the flexible devices in the future applications. Copyright © 2016 John Wiley & Sons, Ltd.

  10. Optical rectification in a strained GaAs{sub 0.9}P{sub 0.1}/GaAs{sub 0.6}P{sub 0.4} quantum dot: Simultaneous effects of electric and magnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    Vinolin, Ada [Dept. of Physics, Madurai Kamaraj University College, Alagarkoil Road, Madurai-625002 (India); Peter, A. John, E-mail: a.john.peter@gmail.com [Dept. of Physics, Government Arts College, Melur-625106, Tamilnadu (India)

    2014-04-24

    Simultaneous effects of electric field and magnetic field on exciton binding energy as a function of dot radius in a cylindrical GaAs{sub 0.9}P{sub 0.1}/GaAs{sub 0.6}P{sub 0.4} strained quantum dot are investigated. The strain contribution includes the strong built-in electric field induced by the spontaneous and piezoelectric polarizations. Numerical calculations are performed using variational procedure within the single band effective mass approximation. Optical rectification in the GaAs{sub 0.9}P{sub 0.1}/GaAs{sub 0.6}P{sub 0.4} quantum dot is computed in the presence of electric and magnetic fields.

  11. CCL20, (gamma)(delta) T cells, and IL-22 in corneal epithelial healing

    Science.gov (United States)

    After corneal epithelial abrasion, leukocytes and platelets rapidly enter the corneal stroma, and CCR6 (+) IL-17(+) gamma delta T cells migrate into the epithelium. Gamma delta T-cell-deficient (TCRd(-/-)) mice have significantly reduced inflammation and epithelial wound healing. Epithelial CCL20 mR...

  12. Quantum dot spectroscopy

    DEFF Research Database (Denmark)

    Leosson, Kristjan

    1999-01-01

    Semiconductor quantum dots ("solid state atoms") are promising candidates for quantum computers and future electronic and optoelectronic devices. Quantum dots are zero-dimensional electronic systems and therefore have discrete energy levels, similar to atoms or molecules. The size distribution of...

  13. Quantum dot spectroscopy

    DEFF Research Database (Denmark)

    Leosson, Kristjan

    Semiconductor quantum dots ("solid-state atoms") are promising candidates for quantum computers and future electronic and optoelectronic devices. Quantum dots are zero-dimensional electronic systems and therefore have discrete energy levels, similar to atoms or molecules. The size distribution of...

  14. Logical Qubit in a Linear Array of Semiconductor Quantum Dots

    Directory of Open Access Journals (Sweden)

    Cody Jones

    2018-06-01

    Full Text Available We design a logical qubit consisting of a linear array of quantum dots, we analyze error correction for this linear architecture, and we propose a sequence of experiments to demonstrate components of the logical qubit on near-term devices. To avoid the difficulty of fully controlling a two-dimensional array of dots, we adapt spin control and error correction to a one-dimensional line of silicon quantum dots. Control speed and efficiency are maintained via a scheme in which electron spin states are controlled globally using broadband microwave pulses for magnetic resonance, while two-qubit gates are provided by local electrical control of the exchange interaction between neighboring dots. Error correction with two-, three-, and four-qubit codes is adapted to a linear chain of qubits with nearest-neighbor gates. We estimate an error correction threshold of 10^{-4}. Furthermore, we describe a sequence of experiments to validate the methods on near-term devices starting from four coupled dots.

  15. Transport through overlapping states in quantum dots and double dot molecules

    International Nuclear Information System (INIS)

    Berkovits, R.

    2006-01-01

    Full Text: We shall review the transport properties of interacting quantum dots with overlapping orbitals for which the orthodox Coulomb blockade picture no longer holds. We shall concentrate on he conductance through a serial double dot structure for which the inter-dot tunneling is stronger than the tunneling to the leads. When the dots are occupied by 1 or 3 electrons the usual Kondo peak is observed. For the case in which 2 electrons occupy the molecule a singlet is formed. Nevertheless, the conductance in that case has a constant non-zero value, and might even be equal to the maximum conductance of 2e 2 /h for certain values of the molecule parameters. We show that this is the result of the subtle interplay between the symmetric and anti-symmetric orbitals of the molecule caused by interactions and interference

  16. Synthesis of quantum dots

    Science.gov (United States)

    McDaniel, Hunter

    2017-10-17

    Common approaches to synthesizing alloyed quantum dots employ high-cost, air-sensitive phosphine complexes as the selenium precursor. Disclosed quantum dot synthesis embodiments avoid these hazardous and air-sensitive selenium precursors. Certain embodiments utilize a combination comprising a thiol and an amine that together reduce and complex the elemental selenium to form a highly reactive selenium precursor at room temperature. The same combination of thiol and amine acts as the reaction solvent, stabilizing ligand, and sulfur source in the synthesis of quantum dot cores. A non-injection approach may also be used. The optical properties of the quantum dots synthesized by this new approach can be finely tuned for a variety of applications by controlling size and/or composition of size and composition. Further, using the same approach, a shell can be grown around a quantum dot core that improves stability, luminescence efficiency, and may reduce toxicity.

  17. One-pot and ultrafast synthesis of nitrogen and phosphorus co-doped carbon dots possessing bright dual wavelength fluorescence emission

    Science.gov (United States)

    Sun, Xiangcheng; Brückner, Christian; Lei, Yu

    2015-10-01

    Very brief microwave heating of aniline, ethylene diamine, and phosphoric acid in water at ambient pressure generated nitrogen and phosphorus co-doped carbon dots (N,P-CDs) that exhibit bright dual blue (centred at 450 nm; 51% quantum yield) and green (centred at 510 nm, 38% quantum yield) fluorescence emission bands. The N,P-CDs were characterized using TEM, XRD, XPS, IR, UV-vis, and fluorescence spectroscopy, demonstrating their partially crystalline carbon, partially amorphous structures, and the incorporation of O, N, and P into the carbogenic scaffold. The N,P-CDs demonstrated excitation-dependent and nearly pH-independent emission properties. The unique dual emission properties lay the foundation for the use of N,P-CDs in ratiometric sensing applications.Very brief microwave heating of aniline, ethylene diamine, and phosphoric acid in water at ambient pressure generated nitrogen and phosphorus co-doped carbon dots (N,P-CDs) that exhibit bright dual blue (centred at 450 nm; 51% quantum yield) and green (centred at 510 nm, 38% quantum yield) fluorescence emission bands. The N,P-CDs were characterized using TEM, XRD, XPS, IR, UV-vis, and fluorescence spectroscopy, demonstrating their partially crystalline carbon, partially amorphous structures, and the incorporation of O, N, and P into the carbogenic scaffold. The N,P-CDs demonstrated excitation-dependent and nearly pH-independent emission properties. The unique dual emission properties lay the foundation for the use of N,P-CDs in ratiometric sensing applications. Electronic supplementary information (ESI) available: Detailed experimental section, XRD, FTIR, explosive sensing and the applications results. See DOI: 10.1039/c5nr05549k

  18. Quantum Dots: Theory

    Energy Technology Data Exchange (ETDEWEB)

    Vukmirovic, Nenad; Wang, Lin-Wang

    2009-11-10

    This review covers the description of the methodologies typically used for the calculation of the electronic structure of self-assembled and colloidal quantum dots. These are illustrated by the results of their application to a selected set of physical effects in quantum dots.

  19. Preparation and characterization of Fe3O4-Ag2O quantum dots decorated cellulose nanofibers as a carrier of anticancer drugs for skin cancer.

    Science.gov (United States)

    Fakhri, Ali; Tahami, Shiva; Nejad, Pedram Afshar

    2017-10-01

    The Best performance drug delivery systems designed with Fe 3 O 4 -Ag 2 O quantum dots decorated cellulose nanofibers which that grafted with Etoposide and Methotrexate. Morphology properties were characterized by Scanning and Transmittance electron microscopy. The crystalline structure of prepared sample was evaluated using by X-ray diffraction. The vibrating sample magnetometer analysis was used for magnetic behavior of samples. The size distributions of Fe 3 O 4 -Ag 2 O QDs/Cellulose fibers nanocomposites indicate that the average diameter was 62.5nm. The Saturation magnetization (Ms) indicates the Fe 3 O 4 -Ag 2 O QDs/Cellulose fibers nanocomposites have ferromagnetic properties in nature. For make carrier, the Iron and Silver should be binds to cellulose nanofibers and to drug molecules and observe in UV-vis spectroscopy. The drug release kinetics was studied in vitro as spectrophotometrically. The release of Etoposide and Methotrexate were carried out with a constant speed, and the equilibrium reached at 24 and 30h with a total amount 78.94% and 63.84%, respectively. The results demonstrated that the obtained Fe 3 O 4 -Ag 2 O quantum dots/cellulose fibers nanocomposites could be applied for drug delivery systems. Cytotoxicity and antioxidant study confirmed the activity of the drug incorporated in nanocomposites. In addition, the cytotoxicity of drug was increased when loaded on nanocomposites, compared to pure Fe 3 O 4 -Ag 2 O quantum dots/cellulose fibers nanocomposites. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. 49 CFR 40.13 - How do DOT drug and alcohol tests relate to non-DOT tests?

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false How do DOT drug and alcohol tests relate to non... TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Employer Responsibilities § 40.13 How do DOT drug and... non-DOT drug and alcohol testing programs. This prohibition includes the use of the DOT forms with...

  1. Fabrication and optical properties of multishell InAs quantum dots on GaAs nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Xin; Zhang, Xia, E-mail: xzhang@bupt.edu.cn; Li, Junshuai; Cui, Jiangong; Ren, Xiaomin [State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876 (China)

    2015-02-07

    Hybrid nanostructures combining nanowires with quantum dots promote the development of nanoelectronic and nanophotonic devices with integrated functionalities. In this work, we present a complex nanostructure with multishell quantum dots grown on nanowires. 1–4 shells of Stranski-Krastanov InAs quantum dots are grown on the sidewalls of GaAs nanowires by metal organic chemical vapor deposition. Different dot shells are separated by 8 nm GaAs spacer shells. With increasing the number of shells, the quantum dots become sparser and tend to align in one array, which is caused by the shrinkage of facets on which dots prefer to grow as well as the strain fields produced by the lower set of dots which influences the migration of In adatoms. The size of quantum dots increases with the increase of shell number due to enhanced strain fields coupling. The spectra of multishell dots exhibit multiwavelength emission, and each peak corresponds to a dot shell. This hybrid structure may serve as a promising element in nanowire intermediate band solar cells, infrared nanolasers, and photodetectors.

  2. DotFETs: MOSFETs strained by a Single SiGE dot in a Low-Temperature ELA Technology

    OpenAIRE

    Biasotto, C.

    2011-01-01

    The work presented in this thesis was performed in the context of the European Sixth Framework Program FP6 project “Disposable Dot Field Effect Transistor for High Speed Si Integrated Circuits”, referred to as the D-DotFET project. The project had the goal of realizing strain-enhanced mobility in CMOS transistors by transferring strain from a self-assembled germanium dot to the channel of a transistor fabricated above the dot. The initial idea was to dispose of the Ge dot underneath the chann...

  3. Vibrational Spectroscopy of the CCI[subscript 4]?[subscript 1] Mode: Effect of Thermally Populated Vibrational States

    Science.gov (United States)

    Gaynor, James D.; Wetterer, Anna M.; Cochran, Rea M.; Valente, Edward J.; Mayer, Steven G.

    2015-01-01

    In our previous article on CCl[subscript 4] in this "Journal," we presented an investigation of the fine structure of the symmetric stretch of carbon tetrachloride (CCl[subscript 4]) due to isotopic variations of chlorine in C[superscript 35]Cl[subscript x][superscript 37]Cl[subscript 4-x]. In this paper, we present an investigation of…

  4. Effect of small doses of ionizing radiation on motility, rosette formation, and antioxidant state of leukocytes under modification of G-proteins by cholera and pertussis toxins

    International Nuclear Information System (INIS)

    Zhirnov, V.V.; Luik, A.I.; Metelitsa, L.A.; Mogilevich, S.E.; Charochkina, L.L.

    2000-01-01

    The responses of motility and rosette formation of leukocytes to small radioactive doses (from 6 centre dot 10 -10 to 6 centre dot 10 -4 Gy) are studied. The influence of these doses on cell functions and oxidative homeostasis are investigated under the modification of transducing components of membrane signal pathways (adenylate cyclase and polyphosphoinositide cascades) with pertussis and cholera toxins

  5. Hyperdense dots mimicking microcalcifications : Mammographic findings

    International Nuclear Information System (INIS)

    Kim, Nam Hyeon; Park, Jeong Mi; Goo, Hyun Woo; Bang, Sun Woo

    1996-01-01

    To differentiate fine hyperdense dots mimicking microcalcifications from true microcalcifications on mammography. Mammograms showing hyperdense dots in ten patients (mean age, 59 years) were evaluated. Two radiologists were asked to differentiate with the naked eye the hyperdense dots seen on ten mammograms and proven microcalcifications seen on ten mammograms. Densitometry was also performed for all lesions and the contrast index was calculated. The shape and distribution of the hyperdense dots were evaluated and enquires were made regarding any history of breast disease and corresponding treatment. Biopsies were performed for two patients with hyperdense dots. Two radiologists made correct diagnoses in 19/20 cases(95%). The contrast index was 0.10-0.88 (mean 0.58) for hyperdense dots and 0.02-0.45 (mean 0.17) for true microcalcifications. The hyperdense dots were finer and homogeneously rounder than the microcalcifications. Distribution of the hyperdense dots was more superficial in subcutaneous fat (seven cases) and subareolar area (six cases). All ten patients with hyperdense dots had history of mastitis and abscesses and had been treated by open drainage (six cases) and/or folk remedy (four cases). In eight patients, herb patches had been attached. Biopsies of hyperdense dots did not show any microcalcification or evidence of malignancy. These hyperdense dots were seen mainly in older patients. Their characteristic density, shape, distribution and clinical history makes differential diagnosis from true microcalcifications easy and could reduce unnecessary diagnostic procedures such as surgical biopsy

  6. Hyperdense dots mimicking microcalcifications : Mammographic findings

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Nam Hyeon; Park, Jeong Mi; Goo, Hyun Woo; Bang, Sun Woo [Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

    1996-12-01

    To differentiate fine hyperdense dots mimicking microcalcifications from true microcalcifications on mammography. Mammograms showing hyperdense dots in ten patients (mean age, 59 years) were evaluated. Two radiologists were asked to differentiate with the naked eye the hyperdense dots seen on ten mammograms and proven microcalcifications seen on ten mammograms. Densitometry was also performed for all lesions and the contrast index was calculated. The shape and distribution of the hyperdense dots were evaluated and enquires were made regarding any history of breast disease and corresponding treatment. Biopsies were performed for two patients with hyperdense dots. Two radiologists made correct diagnoses in 19/20 cases(95%). The contrast index was 0.10-0.88 (mean 0.58) for hyperdense dots and 0.02-0.45 (mean 0.17) for true microcalcifications. The hyperdense dots were finer and homogeneously rounder than the microcalcifications. Distribution of the hyperdense dots was more superficial in subcutaneous fat (seven cases) and subareolar area (six cases). All ten patients with hyperdense dots had history of mastitis and abscesses and had been treated by open drainage (six cases) and/or folk remedy (four cases). In eight patients, herb patches had been attached. Biopsies of hyperdense dots did not show any microcalcification or evidence of malignancy. These hyperdense dots were seen mainly in older patients. Their characteristic density, shape, distribution and clinical history makes differential diagnosis from true microcalcifications easy and could reduce unnecessary diagnostic procedures such as surgical biopsy.

  7. Realization of electrically tunable single quantum dot nanocavities

    Energy Technology Data Exchange (ETDEWEB)

    Hofbauer, Felix Florian Georg

    2009-03-15

    We investigated the design, fabrication and optical investigation of electrically tunable single quantum dot-photonic crystal defect nanocavities operating in both the weak and strong coupling regimes of the light matter interaction. We demonstrate that the quantum confined Stark effect can be employed to quickly and reversibly switch the dot-cavity coupling, simply by varying a gate voltage. Our results show that exciton transitions from individual dots can be tuned by up to {proportional_to}4 meV relative to the nanocavity mode, before the emission quenches due to carrier tunneling escape from the dots. We directly probe spontaneous emission, irreversible polariton decay and the statistics of the emitted photons from a single-dot nanocavity in the weak and strong coupling regimes. New information is obtained on the nature of the dot-cavity coupling in the weak coupling regime and electrical control of zero dimensional polaritons is demonstrated for the first time. The structures investigated are p-i-n photodiodes consisting of an 180nm thick free-standing GaAs membrane into which a two dimensional photonic crystal is formed by etching a triangular lattice of air holes. Low mode volume nanocavities (V{sub mode}<1.6 ({lambda}/n){sup 3}) are realized by omitting 3 holes in a line to form L3 cavities and a single layer of InGaAs self-assembled quantum dots is embedded into the midpoint of the membrane. The nanocavities are electrically contacted via 35 nm thick p- and n-doped contact layers in the GaAs membrane. In the weak coupling regime, time resolved spectroscopy reveals a {proportional_to}7 x shortening of the spontaneous emission lifetime as the dot is tuned through the nanocavity mode, due to the Purcell effect. Upon strongly detuning the same quantum dot transition from the nanocavity mode we observe an additional {proportional_to}8 x lengthening of the spontaneous emission lifetime. These observations unequivocally highlight two regimes of dot

  8. Tanshinone IIA Inhibits Epithelial-Mesenchymal Transition in Bladder Cancer Cells via Modulation of STAT3-CCL2 Signaling

    Directory of Open Access Journals (Sweden)

    Sung-Ying Huang

    2017-07-01

    Full Text Available Tanshinone IIA (Tan-IIA is an extract from the widely used traditional Chinese medicine (TCM Danshen (Salvia miltiorrhiza, and has been found to attenuate the proliferation of bladder cancer (BCa cells (The IC50 were: 5637, 2.6 μg/mL; BFTC, 2 μg/mL; T24, 2.7 μg/mL, respectively.. However, the mechanism of the effect of Tan-IIA on migration inhibition of BCa cells remains unclear. This study investigates the anti-metastatic effect of Tan-IIA in human BCa cells and clarifies its molecular mechanism. Three human BCa cell lines, 5637, BFTC and T24, were used for subsequent experiments. Cell migration and invasion were evaluated by transwell assays. Real-time RT-PCR and western blotting were performed to detect epithelial-mesenchymal transition (EMT-related gene expression. The enzymatic activity of matrix metalloproteinases (MMP was evaluated by zymography assay. Tan-IIA inhibited the migration and invasion of human BCa cells. Tan-IIA suppressed both the protein expression and enzymatic activity of MMP-9/-2 in human BCa cells. Tan-IIA up-regulated the epithelial marker E-cadherin and down-regulated mesenchymal markers such as N-cadherin and Vimentin, along with transcription regulators such as Snail and Slug in BCa cells in a time- and dose-dependent manner. Mechanism dissection revealed that Tan-IIA-inhibited BCa cell invasion could function via suppressed chemokine (C-C motif ligand 2 (CCL2 expression, which could be reversed by the addition of CCL2 recombinant protein. Furthermore, Tan-IIA could inhibit the phosphorylation of the signal transducer and activator of transcription 3 (STAT3 (Tyr705, which cannot be restored by the CCL2 recombinant protein addition. These data implicated that Tan-IIA might suppress EMT on BCa cells through STAT3-CCL2 signaling inhibition. Tan-IIA inhibits EMT of BCa cells via modulation of STAT3-CCL2 signaling. Our findings suggest that Tan-IIA can serve as a potential anti-metastatic agent in BCa therapy.

  9. Intracellular distribution of nontargeted quantum dots after natural uptake and microinjection

    Science.gov (United States)

    Damalakiene, Leona; Karabanovas, Vitalijus; Bagdonas, Saulius; Valius, Mindaugas; Rotomskis, Ricardas

    2013-01-01

    Background: The purpose of this study was to elucidate the mechanism of natural uptake of nonfunctionalized quantum dots in comparison with microinjected quantum dots by focusing on their time-dependent accumulation and intracellular localization in different cell lines. Methods: The accumulation dynamics of nontargeted CdSe/ZnS carboxyl-coated quantum dots (emission peak 625 nm) was analyzed in NIH3T3, MCF-7, and HepG2 cells by applying the methods of confocal and steady-state fluorescence spectroscopy. Intracellular colocalization of the quantum dots was investigated by staining with Lysotracker®. Results: The uptake of quantum dots into cells was dramatically reduced at a low temperature (4°C), indicating that the process is energy-dependent. The uptake kinetics and imaging of intracellular localization of quantum dots revealed three accumulation stages of carboxyl-coated quantum dots at 37°C, ie, a plateau stage, growth stage, and a saturation stage, which comprised four morphological phases: adherence to the cell membrane; formation of granulated clusters spread throughout the cytoplasm; localization of granulated clusters in the perinuclear region; and formation of multivesicular body-like structures and their redistribution in the cytoplasm. Diverse quantum dots containing intracellular vesicles in the range of approximately 0.5–8 μm in diameter were observed in the cytoplasm, but none were found in the nucleus. Vesicles containing quantum dots formed multivesicular body-like structures in NIH3T3 cells after 24 hours of incubation, which were Lysotracker-negative in serum-free medium and Lysotracker-positive in complete medium. The microinjected quantum dots remained uniformly distributed in the cytosol for at least 24 hours. Conclusion: Natural uptake of quantum dots in cells occurs through three accumulation stages via a mechanism requiring energy. The sharp contrast of the intracellular distribution after microinjection of quantum dots in comparison

  10. Search | Page 4 | IDRC - International Development Research Centre

    International Development Research Centre (IDRC) Digital Library (Canada)

    Search | Page 7 | IDRC - International Development Research Centre. Hammou Lammrani has been working for IDRC in the Middle East and North Africa since 2007. Specialising in agriculture, water, and knowledge management, .

  11. IR absorption spectrum (4200-3100 cm-1) of H2O and (H2O)2 in CCl4. Estimates of the equilibrium constant and evidence that the atmospheric water absorption continuum is due to the water dimer

    International Nuclear Information System (INIS)

    Nicolaisen, Flemming M.

    2009-01-01

    IR absorption spectra, 4200-3100 cm -1 , of water in CCl 4 solutions are presented. It is shown that for saturated solutions significant amounts of water are present as dimer (ca. 2%). The IR spectra of the monomer and dimer are retrieved. The integrated absorption coefficients of the monomer absorption are significantly enhanced relative to the gas phase values. The dimer spectrum consists of 5 bands, of which 4 were expected from data from cold beams and cold matrices. The origin of the 'extra' band is discussed. In addition it is argued that the dimer absorption bands intensities must be enhanced relative to the gas phase values. Based on recent calculations of band strengths, and observed frequency shifts relative to the gas phase, the intensity enhancement factors are estimated as well as the monomer/dimer equilibrium constant in CCl 4 solution at T=296 K (K c =1.29 mol -1 L). It is noted that the observed dimer spectrum has a striking resemblance with the water vapour continuum determined by Burch in 1985 which was recently remeasured by Paynter et al. and it is concluded that the atmospheric water absorption continuum in the investigated spectral region must be due to water dimer. Based on the newly published spectral data a revised value of the gas phase equilibrium constant is suggested (K p =0.035 atm -1 at T=296 K) as well as a value for the standard enthalpy of formation, ΔH 0 =15.4 kJ mol -1 .

  12. Chemokine CCL2–CCR2 Signaling Induces Neuronal Cell Death via STAT3 Activation and IL-1β Production after Status Epilepticus

    Science.gov (United States)

    Tian, Dai-Shi; Feng, Li-Jie; Liu, Jun-Li

    2017-01-01

    Elevated levels of chemokine C-C motif ligand 2 (CCL2) and its receptor CCR2 have been reported in patients with temporal lobe epilepsy and in experimental seizures. However, the functional significance and molecular mechanism underlying CCL2–CCR2 signaling in epileptic brain remains largely unknown. In this study, we found that the upregulated CCL2 was mainly expressed in hippocampal neurons and activated microglia from mice 1 d after kainic acid (KA)-induced seizures. Taking advantage of CX3CR1GFP/+:CCR2RFP/+ double-transgenic mice, we demonstrated that CCL2–CCR2 signaling has a role in resident microglial activation and blood-derived monocyte infiltration. Moreover, seizure-induced degeneration of neurons in the hippocampal CA3 region was attenuated in mice lacking CCL2 or CCR2. We further showed that CCR2 activation induced STAT3 (signal transducer and activator of transcription 3) phosphorylation and IL-1β production, which are critical for promoting neuronal cell death after status epilepticus. Consistently, pharmacological inhibition of STAT3 by WP1066 reduced seizure-induced IL-1β production and subsequent neuronal death. Two weeks after KA-induced seizures, CCR2 deficiency not only reduced neuronal loss, but also attenuated seizure-induced behavioral impairments, including anxiety, memory decline, and recurrent seizure severity. Together, we demonstrated that CCL2–CCR2 signaling contributes to neurodegeneration via STAT3 activation and IL-1β production after status epilepticus, providing potential therapeutic targets for the treatment of epilepsy. SIGNIFICANCE STATEMENT Epilepsy is a global concern and epileptic seizures occur in many neurological conditions. Neuroinflammation associated with microglial activation and monocyte infiltration are characteristic of epileptic brains. However, molecular mechanisms underlying neuroinflammation in neuronal death following epilepsy remain to be elucidated. Here we demonstrate that CCL2–CCR2 signaling is

  13. From DOT to Dotty

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    - Module types are interfaces, which can be abstracted. In this talk Martin will present DOT, a particularly simple calculus that can express systems following these principles. DOT has been developed as the foundation of the next version of Scala. He will also report on dotty, a new Scala compiler that implements the constructs of DOT in its core data structures and that uses the lessons learned to drive Scala’s evolution.

  14. CCR9-CCL25 interactions promote cisplatin resistance in breast cancer cell through Akt activation in a PI3K-dependent and FAK-independent fashion

    Directory of Open Access Journals (Sweden)

    Lillard James W

    2011-05-01

    Full Text Available Abstract Background Chemotherapy heavily relies on apoptosis to kill breast cancer (BrCa cells. Many breast tumors respond to chemotherapy, but cells that survive this initial response gain resistance to subsequent treatments. This leads to aggressive cell variants with an enhanced ability to migrate, invade and survive at secondary sites. Metastasis and chemoresistance are responsible for most cancer-related deaths; hence, therapies designed to minimize both are greatly needed. We have recently shown that CCR9-CCL25 interactions promote BrCa cell migration and invasion, while others have shown that this axis play important role in T cell survival. In this study we have shown potential role of CCR9-CCL25 axis in breast cancer cell survival and therapeutic efficacy of cisplatin. Methods Bromodeoxyuridine (BrdU incorporation, Vybrant apoptosis and TUNEL assays were performed to ascertain the role of CCR9-CCL25 axis in cisplatin-induced apoptosis of BrCa cells. Fast Activated Cell-based ELISA (FACE assay was used to quantify In situ activation of PI3Kp85, AktSer473, GSK-3βSer9 and FKHRThr24 in breast cancer cells with or without cisplatin treatment in presence or absence of CCL25. Results CCR9-CCL25 axis provides survival advantage to BrCa cells and inhibits cisplatin-induced apoptosis in a PI3K-dependent and focal adhesion kinase (FAK-independent fashion. Furthermore, CCR9-CCL25 axis activates cell-survival signals through Akt and subsequent glycogen synthase kinase-3 beta (GSK-3β and forkhead in human rhabdomyosarcoma (FKHR inactivation. These results show that CCR9-CCL25 axis play important role in BrCa cell survival and low chemotherapeutic efficacy of cisplatin primarily through PI3K/Akt dependent fashion.

  15. Philippines : tous les projets | Page 4 | CRDI - Centre de recherches ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Région: Central Asia, Far East Asia, South Asia, Philippines, Taiwan, Hong Kong, Singapore. Financement total : CA$ 29,200.00. Mise sur pied d'un réseau philippin de télécentres communautaires. Projet. Plus de 300 télécentres communautaires mènent actuellement leurs activités au sein d'administrations locales partout ...

  16. RTEMS Centre - Support and Maintenance Centre to RTEMS Operating System

    Science.gov (United States)

    Silva, H.; Constantino, A.; Freitas, D.; Coutinho, M.; Faustino, S.; Mota, M.; Colaço, P.; Sousa, J.; Dias, L.; Damjanovic, B.; Zulianello, M.; Rufino, J.

    2009-05-01

    RTEMS CENTRE - Support and Maintenance Centre to RTEMS Operating System is a joint ESA/Portuguese Task Force initiative to develop a support and maintenance centre to the Real-Time Executive for Multiprocessor Systems (RTEMS). This paper gives a high level visibility of the progress, the results obtained and the future work in the RTEMS CENTRE [6] and in the RTEMS Improvement [7] projects. RTEMS CENTRE started officially in November 2006, with the RTEMS 4.6.99.2 version. A full analysis of RTEMS operating system was produced. The architecture was analysed in terms of conceptual, organizational and operational concepts. The original objectives [1] of the centre were primarily to create and maintain technical expertise and competences in this RTOS, to develop a website to provide the European Space Community an entry point for obtaining support (http://rtemscentre.edisoft.pt), to design, develop, maintain and integrate some RTEMS support tools (Timeline Tool, Configuration and Management Tools), to maintain flight libraries and Board Support Packages, to develop a strong relationship with the World RTEMS Community and finally to produce some considerations in ARINC-653, DO-178B and ECSS E-40 standards. RTEMS Improvement is the continuation of the RTEMS CENTRE. Currently the RTEMS, version 4.8.0, is being facilitated for a future qualification. In this work, the validation material is being produced following the Galileo Software Standards Development Assurance Level B [5]. RTEMS is being completely tested, errors analysed, dead and deactivated code removed and tests produced to achieve 100% statement and decision coverage of source code [2]. The SW to exploit the LEON Memory Management Unit (MMU) hardware will be also added. A brief description of the expected implementations will be given.

  17. Synthesis of colloidal InP nanocrystal quantum dots

    International Nuclear Information System (INIS)

    Sirbu, L.; Gutul, T.; Todosiciuc, A.; Danila, M.; Muller, R.; Sarua, A.; Webster, R.; Tiginyanu, I.M.; Ursaki, V.

    2013-01-01

    InP nano dots with the diameter of 4-10 nm were synthesized using sol-gel method. The nano dot dimensions were obtained using TEM, and we found the d(111) spacing to be 0.328 nm which agrees within 3% of the literature value. Prepared nanoparticles where characterized then by Raman spectroscopy and Xray diffraction. Performed measurements confirm good crystalline quality of obtained InP particles, which can be used as a basis for THz emitters, LED, and OLED displays. (authors)

  18. Performance of the dot product function in radiative transfer code SORD

    Science.gov (United States)

    Korkin, Sergey; Lyapustin, Alexei; Sinyuk, Aliaksandr; Holben, Brent

    2016-10-01

    The successive orders of scattering radiative transfer (RT) codes frequently call the scalar (dot) product function. In this paper, we study performance of some implementations of the dot product in the RT code SORD using 50 scenarios for light scattering in the atmosphere-surface system. In the dot product function, we use the unrolled loops technique with different unrolling factor. We also considered the intrinsic Fortran functions. We show results for two machines: ifort compiler under Windows, and pgf90 under Linux. Intrinsic DOT_PRODUCT function showed best performance for the ifort. For the pgf90, the dot product implemented with unrolling factor 4 was the fastest. The RT code SORD together with the interface that runs all the mentioned tests are publicly available from ftp://maiac.gsfc.nasa.gov/pub/skorkin/SORD_IP_16B (current release) or by email request from the corresponding (first) author.

  19. Wetting layers effect on InAs/GaAs quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Sun Chao [State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, P.O. Box 49(BUPT), Xitucheng Road No. 10, Beijing 100876 (China); Lu Pengfei, E-mail: photon.bupt@gmail.com [State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, P.O. Box 49(BUPT), Xitucheng Road No. 10, Beijing 100876 (China); Yu Zhongyuan; Cao Huawei; Zhang Lidong [State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, P.O. Box 49(BUPT), Xitucheng Road No. 10, Beijing 100876 (China)

    2012-11-15

    FEM combining with the K{center_dot}P theory is adopted to systematically investigate the effect of wetting layers on the strain-stress profiles and electronic structures of self-organized InAs quantum dot. Four different kinds of quantum dots are introduced at the same height and aspect ratio. We found that 0.5 nm wetting layer is an appropriate thickness for InAs/GaAs quantum dots. Strain shift down about 3%{approx}4.5% for the cases with WL (0.5 nm) and without WL in four shapes of quantum dots. For band edge energy, wetting layers expand the potential energy gap width. When WL thickness is more than 0.8 nm, the band edge energy profiles cannot vary regularly. The electron energy is affected while for heavy hole this impact on the energy is limited. Wetting layers for the influence of the electronic structure is obviously than the heavy hole. Consequently, the electron probability density function spread from buffer to wetting layer while the center of hole's function moves from QDs internal to wetting layer when introduce WLs. When WLs thickness is larger than 0.8 nm, the electronic structures of quantum dots have changed obviously. This will affect the instrument's performance which relies on the quantum dots' optical properties.

  20. Blocking the recruitment of naive CD4+ T cells reverses immunosuppression in breast cancer

    Science.gov (United States)

    Su, Shicheng; Liao, Jianyou; Liu, Jiang; Huang, Di; He, Chonghua; Chen, Fei; Yang, LinBing; Wu, Wei; Chen, Jianing; Lin, Ling; Zeng, Yunjie; Ouyang, Nengtai; Cui, Xiuying; Yao, Herui; Su, Fengxi; Huang, Jian-dong; Lieberman, Judy; Liu, Qiang; Song, Erwei

    2017-01-01

    The origin of tumor-infiltrating Tregs, critical mediators of tumor immunosuppression, is unclear. Here, we show that tumor-infiltrating naive CD4+ T cells and Tregs in human breast cancer have overlapping TCR repertoires, while hardly overlap with circulating Tregs, suggesting that intratumoral Tregs mainly develop from naive T cells in situ rather than from recruited Tregs. Furthermore, the abundance of naive CD4+ T cells and Tregs is closely correlated, both indicating poor prognosis for breast cancer patients. Naive CD4+ T cells adhere to tumor slices in proportion to the abundance of CCL18-producing macrophages. Moreover, adoptively transferred human naive CD4+ T cells infiltrate human breast cancer orthotopic xenografts in a CCL18-dependent manner. In human breast cancer xenografts in humanized mice, blocking the recruitment of naive CD4+ T cells into tumor by knocking down the expression of PITPNM3, a CCL18 receptor, significantly reduces intratumoral Tregs and inhibits tumor progression. These findings suggest that breast tumor-infiltrating Tregs arise from chemotaxis of circulating naive CD4+ T cells that differentiate into Tregs in situ. Inhibiting naive CD4+ T cell recruitment into tumors by interfering with PITPNM3 recognition of CCL18 may be an attractive strategy for anticancer immunotherapy. PMID:28290464

  1. From micro- to nanomagnetic dots: evolution of the eigenmode spectrum on reducing the lateral size

    International Nuclear Information System (INIS)

    Carlotti, G; Madami, M; Gubbiotti, G; Tacchi, S; Hartmann, F; Emmerling, M; Kamp, M; Worschech, L

    2014-01-01

    Brillouin light scattering experiments and micromagnetic simulations have been exploited to investigate the spectrum of thermally excited magnetic eigenmodes in 10 nm-thick elliptical Permalloy dots, when the longer axis D is scaled down from about 1000 to 100 nm. It is shown that for D larger than about 200 nm the characteristics of the spin-wave eigenmodes are dominated by dipolar energy, while for D in the range of about 100 to 200 nm exchange energy effects cause qualitative and quantitative differences in the spin-wave spectrum. In this ‘mesoscopic’ regime, the usual classification scheme, involving one fundamental mode with large average magnetization and many other modes collected in families with specific symmetries, no longer holds. Rather, one finds the simultaneous presence of two modes with ‘fundamental’ character, i.e. with a significant and comparable value of the average dynamical magnetization: the former is at larger frequency and has its maximum amplitude at the dot's centre, while the latter occurs at lower frequency and is localized at the dot's edges. Interestingly, the maximum intensity swaps from the higher frequency mode to the lower frequency one, just when the dot size is reduced from about 200 to 100 nm. This is relevant in view of the exploitation of nanodots for the design of nanomagnetic devices with lateral dimensions in the above interval, such as memory cells, logic gates, reading heads and spin-torque oscillators. (paper)

  2. From micro- to nanomagnetic dots: evolution of the eigenmode spectrum on reducing the lateral size

    Science.gov (United States)

    Carlotti, G.; Gubbiotti, G.; Madami, M.; Tacchi, S.; Hartmann, F.; Emmerling, M.; Kamp, M.; Worschech, L.

    2014-07-01

    Brillouin light scattering experiments and micromagnetic simulations have been exploited to investigate the spectrum of thermally excited magnetic eigenmodes in 10 nm-thick elliptical Permalloy dots, when the longer axis D is scaled down from about 1000 to 100 nm. It is shown that for D larger than about 200 nm the characteristics of the spin-wave eigenmodes are dominated by dipolar energy, while for D in the range of about 100 to 200 nm exchange energy effects cause qualitative and quantitative differences in the spin-wave spectrum. In this ‘mesoscopic’ regime, the usual classification scheme, involving one fundamental mode with large average magnetization and many other modes collected in families with specific symmetries, no longer holds. Rather, one finds the simultaneous presence of two modes with ‘fundamental’ character, i.e. with a significant and comparable value of the average dynamical magnetization: the former is at larger frequency and has its maximum amplitude at the dot's centre, while the latter occurs at lower frequency and is localized at the dot's edges. Interestingly, the maximum intensity swaps from the higher frequency mode to the lower frequency one, just when the dot size is reduced from about 200 to 100 nm. This is relevant in view of the exploitation of nanodots for the design of nanomagnetic devices with lateral dimensions in the above interval, such as memory cells, logic gates, reading heads and spin-torque oscillators.

  3. Synthesis of CdSe Quantum Dots Using Fusarium oxysporum

    Directory of Open Access Journals (Sweden)

    Takaaki Yamaguchi

    2016-10-01

    Full Text Available CdSe quantum dots are often used in industry as fluorescent materials. In this study, CdSe quantum dots were synthesized using Fusarium oxysporum. The cadmium and selenium concentration, pH, and temperature for the culture of F. oxysporum (Fusarium oxysporum were optimized for the synthesis, and the CdSe quantum dots obtained from the mycelial cells of F. oxysporum were observed by transmission electron microscopy. Ultra-thin sections of F. oxysporum showed that the CdSe quantum dots were precipitated in the intracellular space, indicating that cadmium and selenium ions were incorporated into the cell and that the quantum dots were synthesized with intracellular metabolites. To reveal differences in F. oxysporum metabolism, cell extracts of F. oxysporum, before and after CdSe synthesis, were compared using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE. The results suggested that the amount of superoxide dismutase (SOD decreased after CdSe synthesis. Fluorescence microscopy revealed that cytoplasmic superoxide increased significantly after CdSe synthesis. The accumulation of superoxide may increase the expression of various metabolites that play a role in reducing Se4+ to Se2− and inhibit the aggregation of CdSe to make nanoparticles.

  4. The electronic donation and frequency shifts on the YCCH⋯BH4- boron-bonded complexes (Y = H, CH3, CF3 and CCl3)

    Science.gov (United States)

    Pordeus, Renato Q.; Rego, Danilo G.; Oliveira, Boaz G.

    2015-06-01

    In this theoretical work, the tetrahydroborate ion (BH4-) was used as proton acceptor in the formation of the YCC-H⋯BH4- complexes (Y = H, CH3, CCl3 and CF3). Using B3LYP/6-311++G(d,p) level of theory, the results of structure corroborate with the analyses of infrared spectra showing that the changes in the bond lengths are in good agreement with the frequency shifts of the HCC-H, H3CCC-H, Cl3CCC-H and F3CCC-H proton donors. Based on the calculations carried out by the Quantum Theory of Atoms in Molecules (QTAIM), the reductions of electronic density corroborate with the red shifts in the frequencies of the C-H bonds. In addition to that, the C-H bonds are polarized because the contributions of s orbital diminish whereas of p increase. In line with this, the variations on the atomic radii computed via QTAIM calculations show that carbon outweigh hydrogen as follows (ΔrC > ΔrH). This scenario is indirectly supported by the Bent's rule of the chemical bonding. Although the interaction energies (corrected with BSSE and ZPE) vary between -19 and -67 kJ mol-1, these complexes interact without covalent character.

  5. Stark shifting two-electron quantum dot

    International Nuclear Information System (INIS)

    Dineykhan, M.; Zhaugasheva, S.A.; Duysebaeva, K.S.

    2003-01-01

    Advances in modern technology make it possible to create semiconducting nano-structures (quantum dot) in which a finite number of electrons are 'captured' in a bounded volume. A quantum dot is associated with a quantum well formed at the interface, between two finite-size semiconductors owing to different positions of the forbidden gaps on the energy scale in these semiconductors. The possibility of monitoring and controlling the properties of quantum dots attracts considerable attention to these objects, as a new elemental basis for future generations of computers. The quantum-mechanical effects and image potential play a significant role in the description of the formation mechanism quantum dot, and determined the confinement potential in a two-electron quantum dot only for the spherical symmetric case. In the present talk, we considered the formation dynamics of two-electron quantum dot with violation of spherical symmetry. So, we have standard Stark potential. The energy spectrum two-electron quantum dot were calculated. Usually Stark interactions determined the tunneling phenomena between quantum dots

  6. Hydrogenic impurity in double quantum dots

    International Nuclear Information System (INIS)

    Wang, X.F.

    2007-01-01

    The ground state binding energy and the average interparticle distances for a hydrogenic impurity in double quantum dots with Gaussian confinement potential are studied by the variational method. The probability density of the electron is calculated, too. The dependence of the binding energy on the impurity position is investigated for GaAs quantum dots. The result shows that the binding energy has a minimum as a function of the distance between the two quantum dots when the impurity is located at the center of one quantum dot or at the center of the edge of one quantum dot. When the impurity is located at the center of the two dots, the binding energy decreases monotonically

  7. [Effect of quantum dots CdSe/ZnS's concentration on its fluorescence].

    Science.gov (United States)

    Jin, Min; Huang, Yu-hua; Luo, Ji-xiang

    2015-02-01

    The authors measured the absorption and the fluorescence spectra of the quantum dots CdSe/ZnS with 4 nm in size at different concentration with the use of the UV-Vis absorption spectroscopy and fluorescence spectrometer. The effect of quantum dots CdSe/ZnS's concentration on its fluorescence was especially studied and its physical mechanism was analyzed. It was observed that the optimal concentration of the quantum dots CdSe/ZnS for fluorescence is 2 micromole x L(-1). When the quantum dot's concentration is over 2 micromol x L(-1), the fluorescence is decreased with the increase in the concentration. While the quantum dot's concentration is less than 2 micromol x L(-1), the fluorescence is decreased with the decrease in the concentration. There are two main reasons: (1) fluorescence quenching and 2) the competition between absorption and fluorescence. When the quantum dot's concentration is over 2 micromol x L(-1), the distance between quantum dots is so close that the fluorescence quenching is induced. The closer the distance between quantum dots is, the more serious the fluorescence quenching is induced. Also, in this case, the absorption is so large that some of the quantum dots can not be excited because the incident light can not pass through the whole sample. As a result, the fluorescence is decreased with the increase in the quantum dot's concentration. As the quantum dot's concentration is below 2 micromol x L(-1), the distance between quantum dots is far enough that no more fluorescence quenching is induced. In this case, the fluorescence is determined by the particle number per unit volume. More particle number per unit volume produces more fluorescence. Therefore, the fluorescence is decreased with the decrease in the quantum dot's concentration.

  8. Sub-monolayer dot vertical-cavity surface-emitting lasers

    International Nuclear Information System (INIS)

    Blokhin, S.A.; Maleev, N.A.; Kuz'menkov, A.G.

    2006-01-01

    Vertical-cavity surface-emitting lasers (VCSELs) based on submonolayer InGaAs quantum-dot active region and doped with AlGaAs/GaAs distributed Bragg reflectors were grown by molecular beam epitaxy. 3 μm aperture single-mode VCSELs demonstrate lasing at 980 nm with threshold current of 0.6 mA, maximum output power of 4 mW and external differential efficiency as high as 68%. Ultimately low internal optical losses were measured for these multimode sub-monolayer quantum dot VCSELs [ru

  9. Emission switching in carbon dots coated CdTe quantum dots driving by pH dependent hetero-interactions

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Xiao; Wang, Hao; Yi, Qinghua; Wang, Yun; Cong, Shan; Zhao, Jie; Sun, Yinghui; Zou, Guifu, E-mail: zouguifu@suda.edu.cn, E-mail: jiexiong@uestc.edu.cn [College of Physics, Optoelectronics and Energy and Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006 (China); Qian, Zhicheng [School of Electronic and Information Engineering, Xi' an Jiaotong University, Xi' an 710049 (China); Huang, Jianwen; Xiong, Jie, E-mail: zouguifu@suda.edu.cn, E-mail: jiexiong@uestc.edu.cn [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China); Luo, Hongmei [Department of Chemical and Materials Engineering, New Mexico State University, Las Cruces, New Mexico 88003 (United States)

    2015-11-16

    Due to the different emission mechanism between fluorescent carbon dots and semiconductor quantum dots (QDs), it is of interest to explore the potential emission in hetero-structured carbon dots/semiconducting QDs. Herein, we design carbon dots coated CdTe QDs (CDQDs) and investigate their inherent emission. We demonstrate switchable emission for the hetero-interactions of the CDQDs. Optical analyses indicate electron transfer between the carbon dots and the CdTe QDs. A heterojunction electron process is proposed as the driving mechanism based on N atom protonation of the carbon dots. This work advances our understanding of the interaction mechanism of the heterostructured CDQDs and benefits the future development of optoelectronic nanodevices with new functionalities.

  10. Incommensurate phases in the improper ferroelastic MgGeF sub 6 centre dot 6H sub 2 O:Mn sup 2 sup + studied by means of EPR

    CERN Document Server

    Skrylnik, P G

    2002-01-01

    The results of an EPR study of the inhomogeneous phases existing in the temperature interval T sub C = 311.0 +- 0.3 K < T < T sub i sub 1 = 403 +- 0.3 K in improper ferroelastic crystals of MgGeF sub 6 centre dot 6H sub 2 O:Mn sup 2 sup + are presented. On the basis of the analysis of the temperature and angle dependences of the experimental parameters and numerical calculations, the conclusion has been drawn that at T sub i sub 1 the crystals considered undergo a transition to a structurally modulated phase and the order parameter of this transition may be the angle of the Mg[H sub 2 O] sub 6 sup 2 sup + octahedra rotation around the crystal C sub 3 -axis. From T sub i sub 1 to T sub C the modes of the modulated phase follow according to a completely classical scenario for incommensurate crystals: the origin of the incommensurate structure with plane-wave modulation at T sub i sub 1 , the appearance of structural phase solitons below T sub i sub 2 = 380 +- 0.3 K and decrease of the soliton density to v...

  11. Double Tunneling Injection Quantum Dot Lasers for High Speed Operation

    Science.gov (United States)

    2017-10-23

    Double Tunneling-Injection Quantum Dot Lasers for High -Speed Operation The views, opinions and/or findings contained in this report are those of...SECURITY CLASSIFICATION OF: 1. REPORT DATE (DD-MM-YYYY) 4. TITLE AND SUBTITLE 13. SUPPLEMENTARY NOTES 12. DISTRIBUTION AVAILIBILITY STATEMENT 6...State University Title: Double Tunneling-Injection Quantum Dot Lasers for High -Speed Operation Report Term: 0-Other Email: asryan@vt.edu Distribution

  12. Decoration of TiO_2 nanotube arrays by graphitic-C_3N_4 quantum dots with improved photoelectrocatalytic performance

    International Nuclear Information System (INIS)

    Sun, Bo; Lu, Na; Su, Yan; Yu, Hongtao; Meng, Xiangyu; Gao, Zhanming

    2017-01-01

    Highlights: • TiO_2 nanotube arrays/graphitic-C_3N_4 quantum dots heterojunction was prepared via a facile dipping method. • The optimized dipping duration and concentration of heterojunction were investigated. • The prepared heterojunction extends optical absorption and reduces the recombination of charge carriers. • The photocurrent generated by the optimal g-C_3N_4 QDs/TNTAs photoanode is 4.3 times that of pristine TNTAs. • 98.6% of phenol is degraded in 120 min and the degradation rate is 4.9 times as great as that of pristine TNTAs. - Abstract: In this paper, we present a novel method to improve the photoelectrocatalytic (PEC) property of TiO_2 nanotube arrays (TNTAs) by way of decorating it with visible-light-respond graphitic-C_3N_4 quantum dots (g-C_3N_4 QDs). The g-C_3N_4 QDs/TNTAs heterojunction is successfully prepared using a facile dipping method. The optimal condition of preparing g-C_3N_4 QDs/TNTAs heterojunction is found as 60 min of dipping duration and 0.2 mg mL"−"1 of g-C_3N_4 QDs dipping solution. The fabricated g-C_3N_4 QDs/TNTAs heterojunction shows improved PEC activity comparing to TNTAs due to its better separation capability of photo-generated charges and wider optical absorption. And the photocurrent generated by the optimal g-C_3N_4 QDs/TNTAs photoanode is 4.3 times than that of pristine TNTAs. Besides, the g-C_3N_4 QDs/TNTAs heterojunction also exhibits superior PEC activities in degradation of phenol. 98.6% of phenol is successfully degraded in 120 min and the pseudo-first-order kinetic constant of phenol degradation is 4.9 times as great as that of pristine TNTAs. This work indicates that the g-C_3N_4 QDs/TNTAs heterojunction is expected to be a promising nanomaterial for pollutant degradation and further application in solar energy conversion.

  13. [Effects of intrathecal administration of AM22-52 on mechanical allodynia and CCL2 expression in DRG in bone cancer rats].

    Science.gov (United States)

    Chen, Ya-Juan; Huo, Yuan-Hui; Hong, Yanguo

    2017-02-25

    The pain peptide adrenomedullin (AM) plays a pivotal role in pathological pain. The present study was designed to investigate the effect of blockade of AM receptor on bone cancer pain (BCP) and its mechanism. BCP was developed by inoculation of Walker 256 mammary gland carcinoma cells in the tibia medullary cavity of Sprague Dawley rats. The selective AM receptor antagonist AM 22-52 was administered intrathecally on 15 d after the inoculation. Quantitative real-time PCR was used to detect mRNA level of CC chemokine ligand 2 (CCL2) in dorsal root ganglion (DRG). Double immunofluorescence staining was used to analyze the localizations of CCL2 and AM in DRG of normal rats. The results showed that, from 6 to15 d after the inoculation, the animals showed significant reduction in the mechanical pain threshold in the ipsilateral hindpaw, companied by the decline in bone density of tibia bone. The expression of CCL2 mRNA in DRG of BCP rats was increased by 3 folds (P DRG neurons. These results suggest that AM may play a role in the pathogenesis of BCP. The increased AM bioactivity up-regulates CCL2 expression in DRG, which may contribute to the induction of pain hypersensitivity in bone cancer.

  14. The early activation marker CD69 regulates the expression of chemokines and CD4 T cell accumulation in intestine.

    Directory of Open Access Journals (Sweden)

    Katarina Radulovic

    Full Text Available Migration of naïve and activated lymphocytes is regulated by the expression of various molecules such as chemokine receptors and ligands. CD69, the early activation marker of C-type lectin domain family, is also shown to regulate the lymphocyte migration by affecting their egress from the thymus and secondary lymphoid organs. Here, we aimed to investigate the role of CD69 in accumulation of CD4 T cells in intestine using murine models of inflammatory bowel disease. We found that genetic deletion of CD69 in mice increases the expression of the chemokines CCL-1, CXCL-10 and CCL-19 in CD4(+ T cells and/or CD4(- cells. Efficient in vitro migration of CD69-deficient CD4 T cells toward the chemokine stimuli was the result of increased expression and/or affinity of chemokine receptors. In vivo CD69(-/- CD4 T cells accumulate in the intestine in higher numbers than B6 CD4 T cells as observed in competitive homing assay, dextran sodium sulphate (DSS-induced colitis and antigen-specific transfer colitis. In DSS colitis CD69(-/- CD4 T cell accumulation in colonic lamina propria (cLP was associated with increased expression of CCL-1, CXCL-10 and CCL-19 genes. Furthermore, treatment of DSS-administrated CD69(-/- mice with the mixture of CCL-1, CXCL-10 and CCL-19 neutralizing Abs significantly decreased the histopathological signs of colitis. Transfer of OT-II×CD69(-/- CD45RB(high CD4 T cells into RAG(-/- hosts induced CD4 T cell accumulation in cLP. This study showed CD69 as negative regulator of inflammatory responses in intestine as it decreases the expression of chemotactic receptors and ligands and reduces the accumulation of CD4 T cells in cLP during colitis.

  15. Wetting layers effect on InAs/GaAs quantum dots

    International Nuclear Information System (INIS)

    Sun Chao; Lu Pengfei; Yu Zhongyuan; Cao Huawei; Zhang Lidong

    2012-01-01

    FEM combining with the K·P theory is adopted to systematically investigate the effect of wetting layers on the strain-stress profiles and electronic structures of self-organized InAs quantum dot. Four different kinds of quantum dots are introduced at the same height and aspect ratio. We found that 0.5 nm wetting layer is an appropriate thickness for InAs/GaAs quantum dots. Strain shift down about 3%∼4.5% for the cases with WL (0.5 nm) and without WL in four shapes of quantum dots. For band edge energy, wetting layers expand the potential energy gap width. When WL thickness is more than 0.8 nm, the band edge energy profiles cannot vary regularly. The electron energy is affected while for heavy hole this impact on the energy is limited. Wetting layers for the influence of the electronic structure is obviously than the heavy hole. Consequently, the electron probability density function spread from buffer to wetting layer while the center of hole's function moves from QDs internal to wetting layer when introduce WLs. When WLs thickness is larger than 0.8 nm, the electronic structures of quantum dots have changed obviously. This will affect the instrument's performance which relies on the quantum dots' optical properties.

  16. Decoherence in Nearly-Isolated Quantum Dots

    DEFF Research Database (Denmark)

    Folk, J.; M. Marcus, C.; Harris jr, J.

    2000-01-01

    Decoherence in nearly-isolated GaAs quantum dots is investigated using the change in average Coulomb blockade peak height upon breaking time-reversal symmetry. The normalized change in average peak height approaches the predicted universal value of 1/4 at temperatures well below the single...

  17. Photoluminescence of hybrid quantum dot systems

    Czech Academy of Sciences Publication Activity Database

    Král, Karel; Menšík, Miroslav

    2015-01-01

    Roč. 7, č. 4 (2015), 347-349 ISSN 2164-6627 R&D Projects: GA MŠk LH12236; GA MŠk LH12186 Institutional support: RVO:68378271 ; RVO:61389013 Keywords : quantum dots * energy transfer * electron-phonon interaction Subject RIV: BM - Solid Matter Physics ; Magnetism

  18. TO EVALUATE PREVALENCE OF DIABETES AND HIV IN NEWLY-DIAGNOSED MULTIDRUGRESISTANT TUBERCULOSIS PATIENTS ADMITTED FOR PRETREATMENT EVALUATION IN DOTS PLUS CENTRE, THANJAVUR

    Directory of Open Access Journals (Sweden)

    Namasivayam Kuppusamy

    2017-07-01

    Full Text Available BACKGROUND More than 9 million people fall sick with tuberculosis every year in the world. People with weak immune system as a result of disease like diabetes and HIV are at high risk of developing MDR-TB infection. Proper monitoring and evaluation are needed to control MDR-TB in HIV and diabetes patients. The aim of the study is to find the prevalence of diabetes and HIV among MDR-TB patients admitted for pretreatment evaluation in Dots Plus Centre, Thanjavur Medical College, Tamilnadu. MATERIALS AND METHODS The medical records with datas of 96 patients with MDR-TB who are having diabetes and HIV infection were examined. These cases were diagnosed and registered during January 2015 to December 2015. These patients had drug resistant to first line antituberculosis drugs (isoniazid and rifampicin. Duration of diabetes and HIV infection were noted. Age were categorised in to four groups- 20-29 years, 30-39 years, 40-49 years and above 50 years. The potential risk of association of diabetes, HIV or both with MDR-TB was evaluated by univariate conditional logistic regression model. RESULTS Out of 96 newly-diagnosed MDR-TB patients, prevalence of diabetes is about 34.37%, out of which (84.84% were males and (15.15% were females. Out of 34.37%, 38.54% of patients had controlled diabetes, 61.45% patients had uncontrolled diabetes. Nearly, more than half of diabetes patient falls under uncontrolled diabetes. More number of male patients had diabetes with MDR-TB when compared to females. 10.4% of these persons got oral hypoglycaemic agent and 6.3% got insulin as treatment for diabetes. 1% had irregular treatment with poor compliance. Prevalence of HIV is about 4.16% out of which 75% were males and 25% were females. One patient had both diabetes and HIV with MDR tuberculosis. CONCLUSION In our retrospective study, prevalence of diabetes in MDR-TB patients were more common in males than in females, most of them were in the age groups of 40 years and above

  19. A 2x2 quantum dot array with controllable inter-dot tunnel couplings

    OpenAIRE

    Mukhopadhyay, Uditendu; Dehollain, Juan Pablo; Reichl, Christian; Wegscheider, Werner; Vandersypen, Lieven M. K.

    2018-01-01

    The interaction between electrons in arrays of electrostatically defined quantum dots is naturally described by a Fermi-Hubbard Hamiltonian. Moreover, the high degree of tunability of these systems make them a powerful platform to simulate different regimes of the Hubbard model. However, most quantum dot array implementations have been limited to one-dimensional linear arrays. In this letter, we present a square lattice unit cell of 2$\\times$2 quantum dots defined electrostatically in a AlGaA...

  20. Apigenin inhibits TNFα/IL-1α-induced CCL2 release through IKBK-epsilon signaling in MDA-MB-231 human breast cancer cells.

    Directory of Open Access Journals (Sweden)

    David Bauer

    Full Text Available Mortality associated with breast cancer is attributable to aggressive metastasis, to which TNFα plays a central orchestrating role. TNFα acts on breast tumor TNF receptors evoking the release of chemotactic proteins (e.g. MCP-1/CCL2. These proteins direct inward infiltration/migration of tumor-associated macrophages (TAMs, tumor-associated neutrophils (TANs, myeloid-derived suppressor cells (MDSCs, T-regulatory cells (Tregs, T helper IL-17-producing cells (Th17s, metastasis-associated macrophages (MAMs and cancer-associated fibroblasts (CAFs. Tumor embedded infiltrates collectively enable immune evasion, tumor growth, angiogenesis, and metastasis. In the current study, we investigate the potential of apigenin, a known anti-inflammatory constituent of parsley, to downregulate TNFα mediated release of chemokines from human triple-negative cells (MDA-MB-231 cells. The results show that TNFα stimulation leads to large rise of CCL2, granulocyte macrophage colony-stimulating factor (GMCSF, IL-1α and IL-6, all suppressed by apigenin. While many aspects of the transcriptome for NFkB signaling were evaluated, the data show signaling patterns associated with CCL2 were blocked by apigenin and mediated through suppressed mRNA and protein synthesis of IKBKe. Moreover, the data show that the attenuation of CCL2 by apigenin in the presence TNFα paralleled the suppression of phosphorylated extracellular signal-regulated kinase 1 (ERK 1/ 2. In summary, the obtained findings suggest that there exists a TNFα evoked release of CCL2 and other LSP recruiting cytokines from human breast cancer cells, which can be attenuated by apigenin.

  1. Gas Chromatographic-Ion Trap Mass Spectrometric Analysis of Volatile Organic Compounds by Ion-Molecule Reactions Using the Electron-Deficient Reagent Ion CCl{3/+}

    Science.gov (United States)

    Wang, Cheng-Zhong; Su, Yue; Wang, Hao-Yang; Guo, Yin-Long

    2011-10-01

    When using tetrachloromethane as the reagent gas in gas chromatography-ion trap mass spectrometry equipped with hybrid ionization source, the cation CCl{3/+} was generated in high abundance and further gas-phase experiments showed that such an electron-deficient reagent ion CCl{3/+} could undergo interesting ion-molecule reactions with various volatile organic compounds, which not only present some informative gas-phase reactions, but also facilitate qualitative analysis of diverse volatile compounds by providing unique mass spectral data that are characteristic of particular chemical structures. The ion-molecule reactions of the reagent ion CCl{3/+} with different types of compounds were studied, and results showed that such reactions could give rise to structurally diagnostic ions, such as [M + CCl3 - HCl]+ for aromatic hydrocarbons, [M - OH]+ for saturated cyclic ether, ketone, and alcoholic compounds, [M - H]+ ion for monoterpenes, M·+ for sesquiterpenes, [M - CH3CO]+ for esters, as well as the further fragment ions. The mechanisms of ion-molecule reactions of aromatic hydrocarbons, aliphatic ketones and alcoholic compounds with the reagent ion CCl{3/+} were investigated and proposed according to the information provided by MS/MS experiments and theoretical calculations. Then, this method was applied to study volatile organic compounds in Dendranthema indicum var. aromaticum and 20 compounds, including monoterpenes and their oxygen-containing derivatives, aromatic hydrocarbon and sesquiterpenes were identified using such ion-molecule reactions. This study offers a perspective and an alternative tool for the analysis and identification of various volatile compounds.

  2. Combination of short-length TiO_2 nanorod arrays and compact PbS quantum-dot thin films for efficient solid-state quantum-dot-sensitized solar cells

    International Nuclear Information System (INIS)

    Zhang, Zhengguo; Shi, Chengwu; Chen, Junjun; Xiao, Guannan; Li, Long

    2017-01-01

    Graphical abstract: The TiO_2 nanorod array with the length of 600 nm, the diameter of 20 nm, the areal density of 500 μm"−"2 was successfully prepared. The compact PbS quantum-dot thin film was firstly obtained on the TiO_2 nanorod array by spin-coating-assisted successive ionic layer absorption and reaction with using 1,2-ethanedithiol. The photoelectric conversion efficiency (PCE) of the compact PbS quantum-dot thin film sensitized solar cells achieved 4.10% using spiro-OMeTAD as a hole transporting layer, while the PCE of the PbS quantum-dot sensitized solar cells was only 0.54%. - Highlights: • Preparation of TiO_2 nanorod arrays with the length of 600 nm, diameter of 20 nm. • The compact PbS QD thin film and short-length TiO_2 nanorod array were combined. • EDT addition improved PbS nanoparticle coverage and photovoltaic performance. • The compact PbS QD thin film sensitized solar cell achieved the PCE of 4.10%. - Abstract: Considering the balance of the hole diffusion length and the loading quantity of quantum-dots, the rutile TiO_2 nanorod array with the length of 600 nm, the diameter of 20 nm, and the areal density of 500 μm"−"2 is successfully prepared by the hydrothermal method using the aqueous grown solution of 38 mM titanium isopropoxide and 6 M hydrochloric acid at 170 °C for 105 min. The compact PbS quantum-dot thin film on the TiO_2 nanorod array is firstly obtained by the spin-coating-assisted successive ionic layer absorption and reaction with using 1,2-ethanedithiol (EDT). The result reveals that the strong interaction between lead and EDT is very important to control the crystallite size of PbS quantum-dots and obtain the compact PbS quantum-dot thin film on the TiO_2 nanorod array. The all solid-state sensitized solar cell with the combination of the short-length, high-density TiO_2 nanorod array and the compact PbS quantum-dot thin film achieves the photoelectric conversion efficiency of 4.10%, along with an open

  3. CCL19 as a Chemokine Risk Factor for Posttreatment Lyme Disease Syndrome: a Prospective Clinical Cohort Study

    Science.gov (United States)

    Soloski, Mark J.; Rebman, Alison W.; Crowder, Lauren A.; Wagner, Catriona A.; Robinson, William H.; Bechtold, Kathleen T.

    2016-01-01

    Approximately 10% to 20% of patients optimally treated for early Lyme disease develop persistent symptoms of unknown pathophysiology termed posttreatment Lyme disease syndrome (PTLDS). The objective of this study was to investigate associations between PTLDS and immune mediator levels during acute illness and at several time points following treatment. Seventy-six participants with physician-documented erythema migrans and 26 healthy controls with no history of Lyme disease were enrolled. Sixty-four cytokines, chemokines, and inflammatory markers were measured at each visit for a total of 6 visits over 1 year. An operationalized definition of PTLDS incorporating symptoms and functional impact was applied at 6 months and 1 year following treatment completion, and clinical outcome groups were defined as the return-to-health, symptoms-only, and PTLDS groups. Significance analysis of microarrays identified 7 of the 64 immune mediators to be differentially regulated by group. Generalized logit regressions controlling for potential confounders identified posttreatment levels of the T-cell chemokine CCL19 to be independently associated with clinical outcome group. Receiver operating characteristic analysis identified a CCL19 cutoff of >111.67 pg/ml at 1 month following treatment completion to be 82% sensitive and 83% specific for later PTLDS. We speculate that persistently elevated CCL19 levels among participants with PTLDS may reflect ongoing, immune-driven reactions at sites distal to secondary lymphoid tissue. Our findings suggest the relevance of CCL19 both during acute infection and as an immunologic risk factor for PTLDS during the posttreatment phase. Identification of a potential biomarker predictor for PTLDS provides the opportunity to better understand its pathophysiology and to develop early interventions in the context of appropriate and specific clinical information. PMID:27358211

  4. Dicke states in multiple quantum dots

    Science.gov (United States)

    Sitek, Anna; Manolescu, Andrei

    2013-10-01

    We present a theoretical study of the collective optical effects which can occur in groups of three and four quantum dots. We define conditions for stable subradiant (dark) states, rapidly decaying super-radiant states, and spontaneous trapping of excitation. Each quantum dot is treated like a two-level system. The quantum dots are, however, realistic, meaning that they may have different transition energies and dipole moments. The dots interact via a short-range coupling which allows excitation transfer across the dots, but conserves the total population of the system. We calculate the time evolution of single-exciton and biexciton states using the Lindblad equation. In the steady state the individual populations of each dot may have permanent oscillations with frequencies given by the energy separation between the subradiant eigenstates.

  5. Zinc Cadmium Selenide Cladded Quantum Dot Based Electroluminescent and Nonvolatile Memory Devices

    Science.gov (United States)

    Al-Amody, Fuad H.

    This dissertation presents electroluminescent (EL) and nonvolatile memory devices fabricated using pseudomorphic ZnCdSe-based cladded quantum dots (QDs). These dots were grown using our own in-school built novel reactor. The EL device was fabricated on a substrate of ITO (indium tin oxide) coated glass with the quantum dots sandwiched between anode and cathode contacts with a small barrier layer on top of the QDs. The importance of these cladded dots is to increase the quantum yield of device. This device is unique as they utilize quantum dots that are pseudomorphic (nearly lattice-matched core and the shell of the dot). In the case of floating quantum dot gate nonvolatile memory, cladded ZnCdSe quantum dots are deposited on single crystalline gate insulator (ZnMgS/ZnMgSe), which is grown using metal-organic chemical vapor deposition (MOCVD). The control gate dielectric layer of the nonvolatile memory is Si3N4 or SiO2 and is grown using plasma enhanced chemical vapor deposition (PECVD). The cladded dots are grown using an improved methodology of photo-assisted microwave plasma metal-organic chemical vapor deposition (PMP-MOCVD) enhanced reactor. The cladding composition of the core and shell of the dots was engineered by the help of ultraviolet light which changed the incorporation of zinc (and hence composition of ZnCdSe). This makes ZnxCd1--xSe-ZnyCd1--y Se QDs to have a low composition of zinc in the core than the cladding (x

  6. Downregulation of MIP-1alpha/CCL3 with praziquantel treatment in Schistosoma haematobium and HIV-1 co-infected individuals in a rural community in Zimbabwe

    DEFF Research Database (Denmark)

    Zinyama-Gutsire, Rbl; Gomo, E.; Kallestrup, P

    2009-01-01

    influence. METHODS: To determine levels of MIP-1alpha/CCL3 chemokine in plasma of S. haematobium and HIV-1 co-infected and uninfected individuals in a rural black Zimbabwean community.A cohort was established of HIV-1 and schistosomiasis infection and co-infection comprising 379 participants. Outcome...... measures consisted of HIV-1 and schistosomiasis status and levels of MIP-1alpha/CCL3 in plasma at baseline and three months post treatment. An association was established between MIP-1alpha/CCL3 plasma levels with HIV-1 and S. haematobium infections. RESULTS: A total of 379 adults formed the established...... cohort comprising 76 (20%) men and 303 (80%) women. Mean age was 33.25, range 17 - 62 years. The median MIP-1alpha/CCL3 plasma concentration was significantly higher in S. haematobium infected compared with uninfected individuals (p = 0.029). In contrast, there was no difference in the median MIP-1alpha...

  7. Linewidth statistics of single InGaAs quantum dot photolumincescence lines

    DEFF Research Database (Denmark)

    Leosson, Kristjan; Jensen, Jacob Riis; Hvam, Jørn Märcher

    2000-01-01

    We have used photoluminescence spectroscopy with high spatial and spectral resolution to measure the linewidths of single emission lines from In0.5Ga0.5As/GaAs self-assembled quantum dots. At 10 K, we find a broad, asymmetric distribution of linewidths with a maximum at 50 mu eV. The distribution......-dot luminescence lines depends only weakly on temperature up to 50 K, showing a broadening of 0.4 mu eV/K. Above 50 K, a thermally activated behavior of the linewidth is observed. This temperature dependence is consistent with the discrete energy level structure of the dots....

  8. Optimization of Si–C reaction temperature and Ge thickness in C-mediated Ge dot formation

    Energy Technology Data Exchange (ETDEWEB)

    Satoh, Yuhki, E-mail: yu-ki@ecei.tohoku.ac.jp; Itoh, Yuhki; Kawashima, Tomoyuki; Washio, Katsuyoshi

    2016-03-01

    To form Ge dots on a Si substrate, the effect of thermal reaction temperature of sub-monolayer C with Si (100) was investigated and the deposited Ge thickness was optimized. The samples were prepared by solid-source molecular beam epitaxy with an electron-beam gun for C sublimation and a Knudsen cell for Ge evaporation. C of 0.25 ML was deposited on Si (100) at a substrate temperature of 200 °C, followed by a high-temperature treatment at the reaction temperature (T{sub R}) of 650–1000 °C to create Si–C bonds. Ge equivalent to 2 to 5 nm thick was subsequently deposited at 550 °C. Small and dense dots were obtained for T{sub R} = 750 °C but the dot density decreased and the dot diameter varied widely in the case of lower and higher T{sub R}. A dot density of about 2 × 10{sup 10} cm{sup −2} was achieved for Ge deposition equivalent to 3 to 5 nm thick and a standard deviation of dot diameter was the lowest of 10 nm for 5 nm thick Ge. These results mean that C-mediated Ge dot formation was strongly influenced not only by the c(4 × 4) reconstruction condition through the Si–C reaction but also the relationship between the Ge deposition thickness and the exposed Si (100)-(2 × 1) surface area. - Highlights: • The effect of Si–C reaction temperature on Ge dot formation was investigated. • Small and dense dots were obtained for T{sub R} = 750 °C. • The dot density of about 2 × 10{sup 10} cm{sup −2} was achieved for Ge = 3 to 5 nm. • The standard deviation of dot diameter was the lowest of 10 nm at Ge = 5 nm.

  9. Investigation of carrier dynamics in InAs/GaAsSb quantum dots with different silicon delta-doping levels

    Energy Technology Data Exchange (ETDEWEB)

    Ban, Keun-Yong [Arizona State Univ., Tempe, AZ (United States). School of Electrical, Computer and Energy Engineering; Kim, Yeongho [Korea Research Inst. of Chemistry Technology (KRICT), Daejeon (Korea, Republic of). Division of Metrology for Future Technology; Kuciauskas, Darius [National Renewable Energy Lab. (NREL), Golden, CO (United States); Bremner, Stephen P. [Univ. of New South Wales, Sydney, NSW (Australia). School of Photovoltaic and Renewable Energy Engineering; Honsberg, Christiana B. [Arizona State Univ., Tempe, AZ (United States). School of Electrical, Computer and Energy Engineering

    2016-11-10

    The optical properties of InAs quantum dots (QDs) embedded in a GaAsSb matrix with different delta (d)-doping levels of 0, 2, 4, and 6 electrons per dot (e-/dot), incorporated to control the occupation of QD electronic states, are studied by photoluminescence (PL) spectroscopy. The time-resolved PL data taken at 10 K reveal that the increase of δ-doping density from 2 to 6 e-/dot decreases the recombination lifetime of carriers at ground states of the QDs from 996 ± 36 to 792 ± 19 ps, respectively. Furthermore, the carrier lifetime of the sample with 4 e-/dot is found to increase at a slower rate than that of the undoped sample as temperature increases above 70 K. An Arrhenius plot of the temperature dependent PL intensity indicates that the thermal activation energy of electrons in the QDs, required for carrier escape from the dot ground state to continuum state, is increased when the d-doping density is high enough (>4 e-/dot). These results are attributed to the enhanced Coulomb interaction of electrons provided by the d-doping, leading to reduced thermal quenching of the PL.

  10. Obesity exacerbates colitis-associated cancer via IL-6-regulated macrophage polarisation and CCL-20/CCR-6-mediated lymphocyte recruitment.

    Science.gov (United States)

    Wunderlich, Claudia M; Ackermann, P Justus; Ostermann, Anna Lena; Adams-Quack, Petra; Vogt, Merly C; Tran, My-Ly; Nikolajev, Alexei; Waisman, Ari; Garbers, Christoph; Theurich, Sebastian; Mauer, Jan; Hövelmeyer, Nadine; Wunderlich, F Thomas

    2018-04-25

    Colorectal cancer (CRC) is one of the most lethal cancers worldwide in which the vast majority of cases exhibit little genetic risk but are associated with a sedentary lifestyle and obesity. Although the mechanisms underlying CRC and colitis-associated colorectal cancer (CAC) remain unclear, we hypothesised that obesity-induced inflammation predisposes to CAC development. Here, we show that diet-induced obesity accelerates chemically-induced CAC in mice via increased inflammation and immune cell recruitment. Obesity-induced interleukin-6 (IL-6) shifts macrophage polarisation towards tumour-promoting macrophages that produce the chemokine CC-chemokine-ligand-20 (CCL-20) in the CAC microenvironment. CCL-20 promotes CAC progression by recruiting CC-chemokine-receptor-6 (CCR-6)-expressing B cells and γδ T cells via chemotaxis. Compromised cell recruitment as well as inhibition of B and γδ T cells protects against CAC progression. Collectively, our data reveal a function for IL-6 in the CAC microenvironment via lymphocyte recruitment through the CCL-20/CCR-6 axis, thereby implicating a potential therapeutic intervention for human patients.

  11. Constructing three-dimensional porous graphene-carbon quantum dots/g-C3N4 nanosheet aerogel metal-free photocatalyst with enhanced photocatalytic activity

    Science.gov (United States)

    He, Huijuan; Huang, Langhuan; Zhong, Zijun; Tan, Shaozao

    2018-05-01

    Photocatalysis has been widely considered to be an effective way for solving the worldwide environmental pollution issues. Herein, a new type of three-dimensional (3D) ternary graphene-carbon quantum dots/g-C3N4 nanosheet (GA-CQDs/CNN) aerogel visible-light-driven photocatalyst was synthesized via a two-step hydrothermal method. In this unique ternary photocatalyst, both carbon quantum dots (CQDs) and reduced graphene oxide (rGO) could improve the visible light absorption and promote the charge separation. Furthermore, reduced graphene oxide (rGO) could act as a supportor for the 3D framework. Such a ternary system overcame the drawbacks of bulk g-C3N4 (BCN) and achieved the enhanced photocatalytic activity and long-term stability. As a result, the methyl orange (MO) removal ratio of GA-CQDs/CNN-24% was up to 91.1%, which was about 7.6 times higher than that of bulk g-C3N4 (BCN) under the identical conditions. Moreover that GA-CQDs/CNN-24% exhibited inappreciable loss of photocatalytic activity after four-cycle degradation processes. Finally, the photocatalytic mechanism of GA-CQDs/CNN-24% was interpreted both theoretically and experimentally.

  12. Dot gain compensation in the blue noise mask

    Science.gov (United States)

    Yao, Meng; Parker, Kevin J.

    1995-04-01

    Frequency modulated (FM) halftoning or 'stochastic screening,' has attracted a great deal of attention in the printing industry in recent years. It has several advantages over conventional halftoning. But one serious problem that arises in FM halftoning is dot gain. One approach to stochastic screening uses a specially constructed halftone screen, the blue noise mask (BNM), to produce an unstructured and visually appealing pattern of halftone dots at any gray level. In this paper, we will present methods to correct dot gain with the BNM. Dot gain is related to the area-to-perimeter ration of printed spots. We can exploit this feature in different ways. At a medium level, a B>NM pattern will have 'connected' as well as 'isolated' dots. Normally, as we build down BNM patterns to lower levels, a specific number of white dots will be replace by black dots. Since connected white dots are more likely to be picked than isolated white dots, this will results in substantial dot gain because of the increasing number of isolated white dots. We show that it is possible to constrain the process of constructing a BNM such that isolated dots are preferentially removes, thus significantly reducing dot gain in a BNM.

  13. Electron correlations in quantum dots

    International Nuclear Information System (INIS)

    Tipton, Denver Leonard John

    2001-01-01

    Quantum dot structures confine electrons in a small region of space. Some properties of semiconductor quantum dots, such as the discrete energy levels and shell filling effects visible in addition spectra, have analogies to those of atoms and indeed dots are sometimes referred to as 'artificial atoms'. However, atoms and dots show some fundamental differences due to electron correlations. For real atoms, the kinetic energy of electrons dominates over their mutual Coulomb repulsion energy and for this reason the independent electron approximation works well. For quantum dots the confining potential may be shallower than that of real atoms leading to lower electron densities and a dominance of mutual Coulomb repulsion over kinetic energy. In this strongly correlated regime the independent electron picture leads to qualitatively incorrect results. This thesis concentrates on few-electron quantum dots in the strongly correlated regime both for quasi-one-dimensional and two-dimensional dots in a square confining potential. In this so-called 'Wigner' regime the ground-state electronic charge density is localised near positions of classical electrostatic minima and the interacting electronic spectrum consists of well separated spin multiplets. In the strongly correlated regime the structure of low-energy multiplets is explained by mapping onto lattice models with extended-Hubbard and Heisenberg effective Hamiltonians. The parameters for these effective models are calculated within a Hartree approximation and are shown to reproduce well the exact results obtained by numerical diagonalisation of the full interacting Hamiltonian. Comparison is made between square dots and quantum rings with full rotational symmetry. In the very low-density regime, direct diagonalisation becomes impractical due to excessive computer time for convergence. In this regime a numerical renormalisation group method is applied to one-dimensional dots, enabling effective spin-interactions to be

  14. Gd(iii)-doped carbon dots as a dual fluorescent-MRI probe

    KAUST Repository

    Bourlinos, Athanasios B.; Bakandritsos, Aristides; Kouloumpis, Antonios; Gournis, Dimitrios; Krysmann, Marta; Giannelis, Emmanuel P.; Polakova, Katerina; Safarova, Klara; Hola, Katerina; Zboril, Radek

    2012-01-01

    We describe the synthesis of Gd(iii)-doped carbon dots as dual fluorescence-MRI probes for biomedical applications. The derived Gd(iii)-doped carbon dots show uniform particle size (3-4 nm) and gadolinium distribution and form stable dispersions in water. More importantly, they exhibit bright fluorescence, strong T1-weighted MRI contrast and low cytotoxicity. © The Royal Society of Chemistry 2012.

  15. Magnon-driven quantum dot refrigerators

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yuan; Huang, Chuankun; Liao, Tianjun; Chen, Jincan, E-mail: jcchen@xmu.edu.cn

    2015-12-18

    Highlights: • A three-terminal quantum dot refrigerator is proposed. • The effects of magnetic field, applied voltage, and polarization are considered. • The region that the system can work as a refrigerator is determined. • Two different magnon-driven quantum dot refrigerators are compared. - Abstract: A new model of refrigerator consisting of a spin-splitting quantum dot coupled with two ferromagnetic reservoirs and a ferromagnetic insulator is proposed. The rate equation is used to calculate the occupation probabilities of the quantum dot. The expressions of the electron and magnon currents are obtained. The region that the system can work in as a refrigerator is determined. The cooling power and coefficient of performance (COP) of the refrigerator are derived. The influences of the magnetic field, applied voltage, and polarization of two leads on the performance are discussed. The performances of two different magnon-driven quantum dot refrigerators are compared.

  16. Multi-Excitonic Quantum Dot Molecules

    Science.gov (United States)

    Scheibner, M.; Stinaff, E. A.; Doty, M. F.; Ware, M. E.; Bracker, A. S.; Gammon, D.; Ponomarev, I. V.; Reinecke, T. L.; Korenev, V. L.

    2006-03-01

    With the ability to create coupled pairs of quantum dots, the next step towards the realization of semiconductor based quantum information processing devices can be taken. However, so far little knowledge has been gained on these artificial molecules. Our photoluminescence experiments on single InAs/GaAs quantum dot molecules provide the systematics of coupled quantum dots by delineating the spectroscopic features of several key charge configurations in such quantum systems, including X, X^+,X^2+, XX, XX^+ (with X being the neutral exciton). We extract general rules which determine the formation of molecular states of coupled quantum dots. These include the fact that quantum dot molecules provide the possibility to realize various spin configurations and to switch the electron hole exchange interaction on and off by shifting charges inside the molecule. This knowledge will be valuable in developing implementations for quantum information processing.

  17. 78 FR 48868 - Proposed Cercla Administrative Cost Recovery Settlement; MassDOT, MassDOT Route 1 Right-of-Way...

    Science.gov (United States)

    2013-08-12

    ... Settlement; MassDOT, MassDOT Route 1 Right-of-Way Site, Chelsea, MA AGENCY: Environmental Protection Agency... (``CERCLA''), 42 U.S.C. 9622(h)(1), concerning the MassDOT Route 1 Right-of-Way Site in Chelsea... (OES04-3), Boston, MA 02109-3912 (Telephone No. 617-918-1886) and should refer to: In re: MassDOT Route 1...

  18. Renin-angiotensin system inhibition ameliorates CCl4-induced liver fibrosis in mice through the inactivation of nuclear transcription factor kappa B.

    Science.gov (United States)

    Saber, Sameh; Mahmoud, Amr A A; Helal, Noha S; El-Ahwany, Eman; Abdelghany, Rasha H

    2018-06-01

    Therapeutic interventions for liver fibrosis are still limited due to the complicated molecular pathogenesis. Renin-angiotensin system (RAS) seems to contribute to the development of hepatic fibrosis. Therefore, we aimed to examine the effect of RAS inhibition on CCl 4 -induced liver fibrosis. Mice were treated with silymarin (30 mg·kg -1 ), perindopril (1 mg·kg -1 ), fosinopril (2 mg·kg -1 ), or losartan (10 mg·kg -1 ). The administration of RAS inhibitors improved liver histology and decreased protein expression of alpha smooth muscle actin (α-SMA) and hepatic content of hydroxyproline. These effects found to be mediated via inactivation of nuclear transcription factor kappa B (NFκB) pathway by the inhibition of NFκB p65 phosphorylation at the Ser536 residue and phosphorylation-induced degradation of nuclear factor kappa-B inhibitor alpha (NFκBia) subsequently inhibited NFκB-induced TNF-α and TGF-β1, leading to lower levels of tissue inhibitor of metalloproteinase-1 (TIMP-1) and vascular endothelial growth factor (VEGF). We concluded that the tissue affinity of the angiotensin converting enzyme inhibitors (ACEIs) has no impact on its antifibrotic activity and that interfering the RAS either through the inhibition of ACE or the blockade of AT1R has the same therapeutic benefit. These results suggest RAS inhibitors as promising candidates for further clinical trials in the management of hepatic fibrosis.

  19. Theoretical studies of the dependence of EPR parameters on local structure for the tetragonal Er(3+) centres in YVO4 and ScVO4.

    Science.gov (United States)

    Chai, Rui-Peng; Hao, Dan-Hui; Kuang, Xiao-Yu; Liang, Liang

    2015-11-05

    The dependences of the EPR parameters on the local distortion parameters Δθ and ΔR as well as the crystal-field parameters have been studied by diagonalizing the 364×364 complete energy matrices for a tetragonal Er(3+) centre in the YVO4 and ScVO4 crystals. The results show that the local distortion angle Δθ and the fourth-order crystal-field parameter Ā4 are most sensitive to the EPR g-factors g// and g⊥, whereas the local distortion length ΔR and the second-order parameter Ā2 are less sensitive to the g-factors. Furthermore, we found that the abnormal EPR g-factors for the Er(3+) ion in the ScVO4 may be ascribed to the stronger nephelauxetic effect and covalent bonding effect, as a result of an expanded local distortion for the Er(3+) centre in the ScVO4 crystal. Simultaneously, the contributions of the J-J mixing effects from the terms of excited states to the EPR parameters have been evaluated quantitatively. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. How European centres diagnose, treat, and prevent CIED infections

    DEFF Research Database (Denmark)

    Bongiorni, Maria Grazia; Marinskis, Germanas; Lip, Gregory Y H

    2012-01-01

    in most centres and is substantially under 2% in the majority of centres interviewed. However, there are still differences in terms of prophylactic antibiotic therapy: 8.9% of the centres administer oxacillin as preoperative treatment, 4.4% of them do not give any antibiotic therapy, all centres use some...

  1. Combination of short-length TiO{sub 2} nanorod arrays and compact PbS quantum-dot thin films for efficient solid-state quantum-dot-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhengguo [School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei 230009 (China); School of Chemistry and Chemical Engineering, Beifang University of Nationalities, Yinchuan 750021 (China); Shi, Chengwu, E-mail: shicw506@foxmail.com [School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei 230009 (China); Chen, Junjun; Xiao, Guannan; Li, Long [School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei 230009 (China)

    2017-07-15

    Graphical abstract: The TiO{sub 2} nanorod array with the length of 600 nm, the diameter of 20 nm, the areal density of 500 μm{sup −2} was successfully prepared. The compact PbS quantum-dot thin film was firstly obtained on the TiO{sub 2} nanorod array by spin-coating-assisted successive ionic layer absorption and reaction with using 1,2-ethanedithiol. The photoelectric conversion efficiency (PCE) of the compact PbS quantum-dot thin film sensitized solar cells achieved 4.10% using spiro-OMeTAD as a hole transporting layer, while the PCE of the PbS quantum-dot sensitized solar cells was only 0.54%. - Highlights: • Preparation of TiO{sub 2} nanorod arrays with the length of 600 nm, diameter of 20 nm. • The compact PbS QD thin film and short-length TiO{sub 2} nanorod array were combined. • EDT addition improved PbS nanoparticle coverage and photovoltaic performance. • The compact PbS QD thin film sensitized solar cell achieved the PCE of 4.10%. - Abstract: Considering the balance of the hole diffusion length and the loading quantity of quantum-dots, the rutile TiO{sub 2} nanorod array with the length of 600 nm, the diameter of 20 nm, and the areal density of 500 μm{sup −2} is successfully prepared by the hydrothermal method using the aqueous grown solution of 38 mM titanium isopropoxide and 6 M hydrochloric acid at 170 °C for 105 min. The compact PbS quantum-dot thin film on the TiO{sub 2} nanorod array is firstly obtained by the spin-coating-assisted successive ionic layer absorption and reaction with using 1,2-ethanedithiol (EDT). The result reveals that the strong interaction between lead and EDT is very important to control the crystallite size of PbS quantum-dots and obtain the compact PbS quantum-dot thin film on the TiO{sub 2} nanorod array. The all solid-state sensitized solar cell with the combination of the short-length, high-density TiO{sub 2} nanorod array and the compact PbS quantum-dot thin film achieves the photoelectric conversion

  2. Growth and temperature dependent photoluminescence of InGaAs quantum dot chains

    International Nuclear Information System (INIS)

    Yang, Haeyeon; Kim, Dong-Jun; Colton, John S.; Park, Tyler; Meyer, David; Jones, Aaron M.; Thalman, Scott; Smith, Dallas; Clark, Ken; Brown, Steve

    2014-01-01

    Highlights: • We examine the optical properties of novel quantum dot chains. • Study shows that platelets evolve into quantum dots during heating of the InGaAs platelets encapsulated with GaAs. • Single stack of quantum dots emits light at room temperature. • Quantum dots are of high quality, confirmed by cross-section TEM images and photoluminescence. • Light emission at room temperature weakens beyond the detection limit when the quantum dots form above the critical annealing temperature. - Abstract: We report a study of growth and photoluminescence from a single stack of MBE-grown In 0.4 Ga 0.6 As quantum dot chains. The InGaAs epilayers were grown at a low temperature so that the resulting surfaces remain flat with platelets even though their thicknesses exceed the critical thickness of the conventional Stranski–Krastanov growth mode. The flat InGaAs layers were then annealed at elevated temperatures to induce the formation of quantum dot chains. A reflection high energy electron diffraction study suggests that, when the annealing temperature is at or below 480 °C, the surface of growth front remains flat during the periods of annealing and growth of a 10 nm thick GaAs capping layer. Surprisingly, transmission electron microscopy images do indicate the formation of quantum dot chains, however, so the dot-chains in those samples may form from precursory platelets during the period of temperature ramping and subsequent capping with GaAs due to intermixing of group III elements. The optical emission from the quantum dot layer demonstrates that there is a critical annealing temperature of 480–500 °C above which the properties of the low temperature growth approach are lost, as the optical properties begin to resemble those of quantum dots produced by the conventional Stranski–Krastanov technique

  3. Evaluation of the Effects of Some Brazilian Medicinal Plants on the Production of TNF-α and CCL2 by THP-1 Cells

    Directory of Open Access Journals (Sweden)

    Grasielle S. Gusman

    2015-01-01

    Full Text Available Several plant species are traditionally used in Brazil to treat various inflammatory diseases. Tumor necrosis factor- (TNF- α and chemokine (C-C motif ligand 2 (CCL2 are key inflammatory mediators in diseases like rheumatoid arthritis and atherosclerosis, respectively; nevertheless, only a few extracts have been assayed against these targets. We herein report the effect of 19 plant extracts on TNF-α and CCL2 release by lipopolysaccharide- (LPS- stimulated THP-1 cells, a human monocytic leukemia cell line, along with their radical scavenging activity on DPPH. The extracts of Caryocar brasiliense, Casearia sylvestris, Coccoloba cereifera, and Terminalia glabrescens inhibited TNF-α production in a concentration-dependent manner. Fractionation of these extracts potentiated the anti-TNF-α effect, which was shown to concentrate in polar fractions, mainly composed by polyphenols. Significant CCL2 inhibition was elicited by Lippia sidoides and Terminalia glabrescens extracts, whose fractionation resulted in highly active low polar fractions. All assayed extracts showed strong radical scavenging activity, but antioxidant activity did not correlate with inhibition of TNF-α or CCL2 production. Our results allowed identifying extracts with selective capacity to block cytokine production; therefore, further purification of these extracts may yield molecules that could be useful in the treatment of chronic inflammatory diseases.

  4. Optical transition energy of magneto-polaron in a GaAs{sub 0.9}P{sub 0.1}/GaAs{sub 0.6}P{sub 0.4} quantum dot

    Energy Technology Data Exchange (ETDEWEB)

    Vinolin, Ada [Dept. of Physics, Madurai Kamaraj University College, Alagarkoil Road, Madurai-625002. India (India); Peter, A. John, E-mail: a.john.peter@gmail.com [Dept. of Physics, Govt. Arts College, Melur-625106. Madurai. India (India)

    2015-06-24

    Magneto-LO-polaron in a cylindrical GaAs{sub 0.9} P{sub 0.1} / GaAs{sub 0.6} P{sub 0.4} quantum dot is investigated taking into consideration of geometrical confinement effect. The effects of phonon on the exciton binding energy and the interband emission energy as a function of dot radius are found. The calculations are performed within the single band effective mass approximation using the variational method based on the Lee-Low-Pine LLP transformation.

  5. CCRL1/ACKR4 is expressed in key thymic microenvironments but is dispensable for T lymphopoiesis at steady state in adult mice

    DEFF Research Database (Denmark)

    Lucas, Beth; White, Andrea J.; Ulvmar, Maria H.

    2015-01-01

    Thymus colonisation and thymocyte positioning are regulated by interactions between CCR7 and CCR9, and their respective ligands, CCL19/CCL21 and CCL25. The ligands of CCR7 and CCR9 also interact with the atypical receptor CCRL1 (also known as ACKR4), which is expressed in the thymus and has recen...

  6. Prophylactic Subacute Administration of Zinc Increases CCL2, CCR2, FGF2, and IGF-1 Expression and Prevents the Long-Term Memory Loss in a Rat Model of Cerebral Hypoxia-Ischemia

    Directory of Open Access Journals (Sweden)

    Victor Manuel Blanco-Alvarez

    2015-01-01

    Full Text Available Prophylactic subacute administration of zinc decreases lipoperoxidation and cell death following a transient cerebral hypoxia-ischemia, thus suggesting neuroprotective and preconditioning effects. Chemokines and growth factors are also involved in the neuroprotective effect in hypoxia-ischemia. We explored whether zinc prevents the cerebral cortex-hippocampus injury through regulation of CCL2, CCR2, FGF2, and IGF-1 expression following a 10 min of common carotid artery occlusion (CCAO. Male rats were grouped as follows: (1 Zn96h, rats injected with ZnCl2 (one dose every 24 h during four days; (2 Zn96h + CCAO, rats treated with ZnCl2 before CCAO; (3 CCAO, rats with CCAO only; (4 Sham group, rats with mock CCAO; and (5 untreated rats. The cerebral cortex-hippocampus was dissected at different times before and after CCAO. CCL2/CCR2, FGF2, and IGF-1 expression was assessed by RT-PCR and ELISA. Learning in Morris Water Maze was achieved by daily training during 5 days. Long-term memory was evaluated on day 7 after learning. Subacute administration of zinc increased expression of CCL2, CCR2, FGF2, and IGF-1 in the early and late phases of postreperfusion and prevented the CCAO-induced memory loss in the rat. These results might be explained by the induction of neural plasticity because of the expression of CCL2 and growth factors.

  7. Biocompatible Quantum Dots for Biological Applications

    Science.gov (United States)

    Rosenthal, Sandra J.; Chang, Jerry C.; Kovtun, Oleg; McBride, James R.; Tomlinson, Ian D.

    2011-01-01

    Semiconductor quantum dots are quickly becoming a critical diagnostic tool for discerning cellular function at the molecular level. Their high brightness, long-lasting, sizetunable, and narrow luminescence set them apart from conventional fluorescence dyes. Quantum dots are being developed for a variety of biologically oriented applications, including fluorescent assays for drug discovery, disease detection, single protein tracking, and intracellular reporting. This review introduces the science behind quantum dots and describes how they are made biologically compatible. Several applications are also included, illustrating strategies toward target specificity, and are followed by a discussion on the limitations of quantum dot approaches. The article is concluded with a look at the future direction of quantum dots. PMID:21276935

  8. Quantum measurement of coherent tunneling between quantum dots

    International Nuclear Information System (INIS)

    Wiseman, H. M.; Utami, Dian Wahyu; Sun, He Bi; Milburn, G. J.; Kane, B. E.; Dzurak, A.; Clark, R. G.

    2001-01-01

    We describe the conditional and unconditional dynamics of two coupled quantum dots when one dot is subjected to a measurement of its occupation number by coupling it to a third readout dot via the Coulomb interaction. The readout dot is coupled to source and drain leads under weak bias, and a tunnel current flows through a single bound state when energetically allowed. The occupation of the quantum dot near the readout dot shifts the bound state of the readout dot from a low conducting state to a high conducting state. The measurement is made by continuously monitoring the tunnel current through the readout dot. We show that there is a difference between the time scale for the measurement-induced decoherence between the localized states of the dots, and the time scale on which the system becomes localized due to the measurement

  9. Chemokines involved in protection from colitis by CD4+CD25+ regulatory T cells

    DEFF Research Database (Denmark)

    Kristensen, Nanna Ny; Brudzewsky, Dan; Gad, Monika

    2006-01-01

    /chemokine receptor-specific gene expression profiling system of 67 genes, the authors have determined the expression profile of chemokine and chemokine receptor genes in the rectum of colitic mice and in mice that have been protected fromcolitis by CD4CD25 regulatory T cells. In mice protected from colitis......, the authors found down regulation of the mRNA expression of the inflammatory chemokine receptors CCR1 and CXCR3 and their ligands CXCL9, CXCL10, CCL5, and CCL7. Also the transcripts for CCR9, CCL25, CCL17, and CXCL1 are found down regulated in protected compared with colitic animals. In addition, the authors......' results suggest that CCL20 is used by CCR6 regulatory T cells in the complex process of controlling colitis because transcripts for this chemokine were expressed to a higher level in protected animals. The chemokine pathways identified in the present study may be of importance for the development of new...

  10. Administration of Lactobacillus salivarius LI01 or Pediococcus pentosaceus LI05 prevents CCl4-induced liver cirrhosis by protecting the intestinal barrier in rats.

    Science.gov (United States)

    Shi, Ding; Lv, Longxian; Fang, Daiqiong; Wu, Wenrui; Hu, Chenxia; Xu, Lichen; Chen, Yanfei; Guo, Jing; Hu, Xinjun; Li, Ang; Guo, Feifei; Ye, Jianzhong; Li, Yating; Andayani, Dewi; Li, Lanjuan

    2017-07-31

    Alterations in the gut microbiome have been reported in liver cirrhosis, and probiotic interventions are considered a potential treatment strategy. This study aimed to evaluate the effects and mechanisms of Lactobacillus salivarius LI01, Pediococcus pentosaceus LI05, Lactobacillus rhamnosus GG, Clostridium butyricum MIYAIRI and Bacillus licheniformis Zhengchangsheng on CCl 4 -induced cirrhotic rats. Only administration of LI01 or LI05 prevented liver fibrosis and down-regulated the hepatic expression of profibrogenic genes. Serum endotoxins, bacterial translocations (BTs), and destruction of intestinal mucosal ultrastructure were reduced in rats treated with LI01 or LI05, indicating maintenance of the gut barrier as a mechanism; this was further confirmed by the reduction of not only hepatic inflammatory cytokines, such as TNF-α, IL-6, and IL-17A, but also hepatic TLR2, TLR4, TLR5 and TLR9. Metagenomic sequencing of 16S rRNA gene showed an increase in potential beneficial bacteria, such as Elusimicrobium and Prevotella, and a decrease in pathogenic bacteria, such as Escherichia. These alterations in gut microbiome were correlated with profibrogenic genes, gut barrier markers and inflammatory cytokines. In conclusion, L. salivarius LI01 and P. pentosaceus LI05 attenuated liver fibrosis by protecting the intestinal barrier and promoting microbiome health. These results suggest novel strategies for the prevention of liver cirrhosis.

  11. DNA nanosensor based on biocompatible graphene quantum dots and carbon nanotubes.

    Science.gov (United States)

    Qian, Zhao Sheng; Shan, Xiao Yue; Chai, Lu Jing; Ma, Juan Juan; Chen, Jian Rong; Feng, Hui

    2014-10-15

    An ultrasensitive nanosensor based on fluorescence resonance energy transfer (FRET) between biocompatible graphene quantum dots and carbon nanotubes for DNA detection was reported. We take advantage of good biocompatibility and strong fluorescence of graphene quantum dots, base pairing specificity of DNA and unique fluorescence resonance energy transfer between graphene quantum dots and carbon nanotubes to achieve the analysis of low concentrations of DNA. Graphene quantum dots with high quantum yield up to 0.20 were prepared and served as the fluorophore of DNA probe. FRET process between graphene quantum dots-labeled probe and oxidized carbon nanotubes is easily achieved due to their efficient self-assembly through specific π-π interaction. This nanosensor can distinguish complementary and mismatched nucleic acid sequences with high sensitivity and good reproducibility. The detection method based on this nanosensor possesses a broad linear span of up to 133.0 nM and ultralow detection limit of 0.4 nM. The constructed nanosensor is expected to be highly biocompatible because of all its components with excellent biocompatibility. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. The MCP-1, CCL-5 and SDF-1 chemokines as pro-inflammatory markers in generalized anxiety disorder and personality disorders.

    Science.gov (United States)

    Ogłodek, Ewa A; Szota, Anna M; Just, Marek J; Moś, Danuta M; Araszkiewicz, Aleksander

    2015-02-01

    The co-occurrence of generalized anxiety disorder and personality disorders suggests the existence of association between the neurobiological predispositions leading to the development of these disorders and activation of cytokine system. Pro-inflammatory chemokines such as CCL-5/RANTES (regulated upon activation normal T cell expressed and secreted) and CXCL12/SDF-1 (stromal derived factor) play an important role in immune response. A total of 160 participants were enrolled in the study, 120 of whom comprised the study group (people with the dual diagnosis of personality disorder and generalized anxiety disorder). The mean age was 41.4 ± 3.5 years (range: 20-44 years). The control group consisted of 40 healthy individuals in the mean age of 40.8 ± 3.1 years (range: 20-43 years). A blood sample was collected from each participant and the plasma levels of the CCL-2/MCP-1 (monocyte chemoattractant protein-1), RANTES and SDF-1 chemokines were determined by ELISA. Increased levels of MCP-1 and SDF-1 were found both in women and in men versus the control group for all types of personality disorders. The levels of CCL-5 in men were significantly increased versus the control group and significantly higher in women than in men. Neither women nor men with avoidant or obsessive-compulsive personality disorder showed any significant differences in MCP-1 or SFD-1 levels. In subjects with borderline personality disorder, the levels of the study chemokines were higher in women than in men. Our study has shown the need for determination of proinflammatory interleukins which are considered as biomarkers of personality disorders and generalized anxiety disorders. Copyright © 2014 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  13. RANTES/CCL5 and risk for coronary events: Results from the MONICA/KORA Augsburg case-cohort, Athero-express and CARDIoGRAM studies

    OpenAIRE

    Kathiresan, Sekar; Reilly, Muredach; Samani, Nilesh; Schunkert, Heribert; Erdmann, Jeanette; Moll, Frans; Boerwinkle, Eric; Hall, Anne; Hengstenberg, Christian; König, Inke; Laaksonen, Reijo; McPherson, Ruth; Thompson, John; Thorsteinsdottir, Unnur; Ziegler, Andreas

    2011-01-01

    textabstractBackground: The chemokine RANTES (regulated on activation, normal T-cell expressed and secreted)/CCL5 is involved in the pathogenesis of cardiovascular disease in mice, whereas less is known in humans. We hypothesised that its relevance for atherosclerosis should be reflected by associations between CCL5 gene variants, RANTES serum concentrations and protein levels in atherosclerotic plaques and risk for coronary events. Methods and Findings: We conducted a case-cohort study withi...

  14. Hydrothermal green synthesis of magnetic Fe3O4-carbon dots by lemon and grape fruit extracts and as a photoluminescence sensor for detecting of E. coli bacteria.

    Science.gov (United States)

    Ahmadian-Fard-Fini, Shahla; Salavati-Niasari, Masoud; Ghanbari, Davood

    2018-10-05

    The aim of this work is preparing of a photoluminescence nanostructures for rapid detection of bacterial pathogens. Firstly, carbon dots (CDs) were synthesized by grape fruit, lemon, turmeric extracts and hydrothermal method. Then Fe 3 O 4 (magnetite) nanoparticles was achieved using these bio-compatible capping agents. Finally, magnetite-carbon dots were synthesized as a novel magnetic and photoluminescence nanocomposite. X-ray diffraction (XRD) confirms the crystallinity and phase of the products, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) investigate the morphology, shape and size of the magnetite, carbon dot and nanocomposites. Fourier transform infrared (FT-IR) spectroscopy shows the purity of the nanostructures. Ultraviolet-visible (UV-Vis) absorption and photo-luminescence (PL) spectroscopy show suitable photo-luminescence under ultraviolet irradiation. Vibrating sample magnetometer (VSM) shows super paramagnetic property of the product. Interestingly carbon dots were used as a non-toxic photoluminescence sensor for detecting of Escherichia coli (E. coli) bacteria. Results show quenching of photoluminescence of the CDs nanocomposite by increasing amount of E. coli bacteria. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. PLAG (1-Palmitoyl-2-Linoleoyl-3-Acetyl-rac-Glycerol Modulates Eosinophil Chemotaxis by Regulating CCL26 Expression from Epithelial Cells.

    Directory of Open Access Journals (Sweden)

    Jinseon Jeong

    Full Text Available Increased number of eosinophils in the circulation and sputum is associated with the severity of asthma. The respiratory epithelium produces chemokine (C-C motif ligands (CCL which recruits and activates eosinophils. A chemically synthesized monoacetyl-diglyceride, PLAG (1-palmitoyl-2-linoleoyl-3-acetyl-rac-glycerol is a major constituent in the antlers of Sika deer (Cervus nippon Temminck which has been used in oriental medicine. This study was aimed to investigate the molecular mechanism of PLAG effect on the alleviation of asthma phenotypes. A549, a human alveolar basal epithelial cell, and HaCaT, a human keratinocyte, were activated by the treatment of interleukin-4 (IL-4, and the expression of chemokines, known to be effective on the induction of eosinophil migration was analyzed by RT-PCR. The expression of IL-4 induced genes was modulated by the co-treatment of PLAG. Especially, CCL26 expression from the stimulated epithelial cells was significantly blocked by PLAG, which was confirmed by ELISA. The transcriptional activity of signal transducer and activator of transcription 6 (STAT6, activated by IL-4 mediated phosphorylation and nuclear translocation, was down-regulated by PLAG in a concentration-dependent manner. In ovalbumin-induced mouse model, the infiltration of immune cells into the respiratory tract was decreased by PLAG administration. Cytological analysis of the isolated bronchoalveolar lavage fluid (BALF cells proved the infiltration of eosinophils was significantly reduced by PLAG. In addition, PLAG inhibited the migration of murine bone marrow-derived eosinophils, and human eosinophil cell line, EoL-1, which was induced by the addition of A549 culture medium.

  16. Metamorphic quantum dots: Quite different nanostructures

    International Nuclear Information System (INIS)

    Seravalli, L.; Frigeri, P.; Nasi, L.; Trevisi, G.; Bocchi, C.

    2010-01-01

    In this work, we present a study of InAs quantum dots deposited on InGaAs metamorphic buffers by molecular beam epitaxy. By comparing morphological, structural, and optical properties of such nanostructures with those of InAs/GaAs quantum dot ones, we were able to evidence characteristics that are typical of metamorphic InAs/InGaAs structures. The more relevant are: the cross-hatched InGaAs surface overgrown by dots, the change in critical coverages for island nucleation and ripening, the nucleation of new defects in the capping layers, and the redshift in the emission energy. The discussion on experimental results allowed us to conclude that metamorphic InAs/InGaAs quantum dots are rather different nanostructures, where attention must be put to some issues not present in InAs/GaAs structures, namely, buffer-related defects, surface morphology, different dislocation mobility, and stacking fault energies. On the other hand, we show that metamorphic quantum dot nanostructures can provide new possibilities of tailoring various properties, such as dot positioning and emission energy, that could be very useful for innovative dot-based devices.

  17. Efficient carbon dots/NiFe-layered double hydroxide/BiVO4 photoanodes for photoelectrochemical water splitting

    Science.gov (United States)

    Lv, Xiaowei; Xiao, Xin; Cao, Minglei; Bu, Yi; Wang, Chuanqing; Wang, Mingkui; Shen, Yan

    2018-05-01

    Modification of semiconductor photoanodes with oxygen evolution catalyst (OEC) is an effective approach for improving photoelectrochemical (PEC) water splitting efficiency. In the configuration, how to increase the activity of OEC is crucial to further improve PEC performance. Herein, a ternary photoanode system was designed to enhance PEC efficiency of photoelectrodes through introducing carbon dots (CDs), NiFe-layered double hydroxide (NiFe-LDH) nanosheets on BiVO4 particles. Systematic research shows that NiFe-LDH serves as an OEC which accelerates oxygen evolution kinetics, while the introduction of CDs can further reduce charge transfer resistance and overpotential for oxygen evolution. Under the synergistic effect of NiFe-LDH and CDs, the photocurrent and incident photon to current conversion efficiency (IPCE) of the resulting CDs/NiFe-LDH/BiVO4 photoanode is improved significantly than those of the NiFe-LDH/BiVO4 electrode. Consequently, such a ternary heterostructure could be an alternative way to further enhance PEC water splitting performance.

  18. Quantum dots: Rethinking the electronics

    Energy Technology Data Exchange (ETDEWEB)

    Bishnoi, Dimple [Department of Physics, S. S. Jain Subodh PG College, Jaipur, Rajasthan Pin-302004 (India)

    2016-05-06

    In this paper, we demonstrate theoretically that the Quantum dots are quite interesting for the electronics industry. Semiconductor quantum dots (QDs) are nanometer-scale crystals, which have unique photo physical, quantum electrical properties, size-dependent optical properties, There small size means that electrons do not have to travel as far as with larger particles, thus electronic devices can operate faster. Cheaper than modern commercial solar cells while making use of a wider variety of photon energies, including “waste heat” from the sun’s energy. Quantum dots can be used in tandem cells, which are multi junction photovoltaic cells or in the intermediate band setup. PbSe (lead selenide) is commonly used in quantum dot solar cells.

  19. The electronic properties of semiconductor quantum dots

    International Nuclear Information System (INIS)

    Barker, J.A.

    2000-10-01

    This work is an investigation into the electronic behaviour of semiconductor quantum dots, particularly self-assembled quantum dot arrays. Processor-efficient models are developed to describe the electronic structure of dots, deriving analytic formulae for the strain tensor, piezoelectric distribution and diffusion- induced evolution of the confinement potential, for dots of arbitrary initial shape and composition profile. These models are then applied to experimental data. Transitions due to individual quantum dots have a narrow linewidth as a result of their discrete density of states. By contrast, quantum dot arrays exhibit inhomogeneous broadening which is generally attributed to size variations between the individual dots in the ensemble. Interpreting the results of double resonance spectroscopy, it is seen that variation in the indium composition of the nominally InAs dots is also present. This result also explains the otherwise confusing relationship between the spread in the ground-state and excited-state transition energies. Careful analysis shows that, in addition to the variations in size and composition, some other as yet unidentified broadening mechanism must also be present. The influence of rapid thermal annealing on dot electronic structure is also considered, finding that the experimentally observed blue-shift and narrowing of the photoluminescence linewidth may both be explained in terms of normal In/Ga interdiffusion. InAs/GaAs self-assembled quantum dots are commonly assumed to have a pyramidal geometry, so that we would expect the energy separation of the ground-state electron and hole levels in the dot to be largest at a positive applied field. This should also be the case for any dot of uniform composition whose shape tapers inwards from base to top, counter to the results of experimental Stark-shift spectroscopy which show a peak transition energy at a negative applied field. It is demonstrated that this inversion of the ground state

  20. The DotA protein from Legionella pneumophila is secreted by a novel process that requires the Dot/Icm transporter

    OpenAIRE

    Nagai, Hiroki; Roy, Craig R.

    2001-01-01

    Legionella pneumophila requires the dot/icm genes to create an organelle inside eukaryotic host cells that will support bacterial replication. The dot/icm genes are predicted to encode a type IV-related secretion apparatus. However, no proteins have been identified that require the dot/icm genes for secretion. In this study we show that the DotA protein, which was previously found to be a polytopic membrane protein, is secreted by the Dot/Icm transporter into culture supernatants. Secreted Do...

  1. On the size and temperature dependence of the energy gap in cadmium-selenide quantum dots embedded in fluorophosphate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Lipatova, Zh. O., E-mail: zluka-yo@mail.ru; Kolobkova, E. V.; Babkina, A. N.; Nikonorov, N. V. [ITMO University (Russian Federation)

    2017-03-15

    The temperature and size dependences of the energy gap in CdSe quantum dots with diameters of 2.4, 4.0, and 5.2 nm embedded in fluorophosphate glasses are investigated. It is shown that the temperature coefficient of the band gap dE{sub g}/dT in the quantum dots differs from the bulk value and depends strictly on the dot size. It is found that, furthermore, the energy of each transition in these quantum dots is characterized by an individual temperature coefficient dE/dT.

  2. Design of quaternary logic circuit using quantum dot gate-quantum dot channel FET (QDG-QDCFET)

    Science.gov (United States)

    Karmakar, Supriya

    2014-10-01

    This paper presents the implementation of quaternary logic circuits based on quantum dot gate-quantum dot channel field effect transistor (QDG-QDCFET). The super lattice structure in the quantum dot channel region of QDG-QDCFET and the electron tunnelling from inversion channel to the quantum dot layer in the gate region of a QDG-QDCFET change the threshold voltage of this device which produces two intermediate states between its ON and OFF states. This property of QDG-QDCFET is used to implement multi-valued logic for future multi-valued logic circuit. This paper presents the design of basic quaternary logic operation such as inverter, AND and OR operation based on QDG-QDCFET.

  3. Characterization of electronic charged states of P-doped Si quantum dots using AFM/Kelvin probe

    International Nuclear Information System (INIS)

    Makihara, Katsunori; Xu, Jun; Ikeda, Mitsuhisa; Murakami, Hideki; Higashi, Seiichiro; Miyazaki, Seiichi

    2006-01-01

    Phosphorous doping to Si quantum dots was performed by a pulse injection of 1% PH 3 diluted with He during the dot formation on thermally grown SiO 2 from thermal decomposition of pure SiH 4 , and electron charging to and discharging from P-doped Si dots were studied to characterize their electronic charged states using a Kelvin probe technique in atomic force microscopy (AFM). The potential change corresponding to the extraction of one electron from each of the P-doped Si dots was observed after applying a tip bias as low as + 0.2 V while for undoped Si dots, with almost the same size as P-doped Si dots, almost the same amount of the potential change was detectable only when the tip bias was increased to ∼ 1 V. It is likely that, for P-doped Si dots, the electron extraction from the conduction band occurs and results in a positively charged state with ionized P donor

  4. 14 CFR 300.8 - Gifts and hospitality and other conduct affecting DOT employees.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Gifts and hospitality and other conduct... CHAPTER § 300.8 Gifts and hospitality and other conduct affecting DOT employees. (a) No person, otherwise... for persons interested in the business of DOT to provide hospitality, gifts, entertainment, or favors...

  5. Different valence Sn doping - A simple way to detect oxygen concentration variation of ZnO quantum dots synthesized under ultrasonic irradiation.

    Science.gov (United States)

    Yang, Weimin; Zhang, Bing; Zhang, Qitu; Wang, Lixi; Song, Bo; Wu, Fan; Wong, C P

    2017-09-01

    An ultrasonic method is employed to synthesize the Sn doped Zn 0.95 Sn 0.05 O quantum dots with green light emission. Sn 2+ and Sn 4+ ions are used to create different optical defects inside Zn 0.95 Sn 0.05 O quantum dots and the changing trend of oxygen concentration under different ultrasonic irradiation power are investigated. The photoluminescence spectra are employed to characterize the optical defects of Zn 0.95 Sn 0.05 O quantum dots. The UV-vis spectra are used to study the band gap of Zn 0.95 Sn 0.05 O quantum dots, which is influenced by their sizes. The results indicate that ultrasonic power would influence the size of Zn 0.95 Sn 0.05 O quantum dots as well as the type and quantity of defects in ZnO quantum dots. Changing trends in size of Sn 2+ and Sn 4+ doped Zn 0.95 Sn 0.05 O quantum dots are quite similar with each other, while the changing trends in optical defects types and concentration of Sn 2+ and Sn 4+ doped Zn 0.95 Sn 0.05 O quantum dots are different. The difference of the optical defects concentration changing between Sn 2+ doped Zn 0.95 Sn 0.05 O quantum dots (V O defects) and Sn 4+ doped Zn 0.95 Sn 0.05 O quantum dots (O Zn and O i defects) shows that the formation process of ZnO under ultrasonic irradiation wiped oxygen out. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Peripheral Neuropathic Facial/Trigeminal Pain and RANTES/CCL5 in Jawbone Cavitation

    Directory of Open Access Journals (Sweden)

    Johann Lechner

    2015-01-01

    Full Text Available Introduction. In this study, we elucidate the possible causative role of chronic subclinical inflammation in jawbone of patients with atypical facial pain (AFP and trigeminal neuralgia (TRN in the local overexpression of the chemokine regulated on activation and normal T-cell expressed and secreted (RANTES/C-C motif ligand 5 CCL5. Neurons contain opioid receptors that transmit antipain reactions in the peripheral and central nervous system. Proinflammatory chemokines like RANTES/CCL5 desensitize μ-opioid receptors in the periphery sensory neurons and it has been suggested that RANTES modifies the nociceptive reaction. Materials and Methods. In 15 patients with AFP/TRN, we examined fatty degenerated jawbone (FDOJ samples for the expression of seven cytokines by multiplex analysis and compared these results with healthy jawbones. Results. Each of these medullary jawbone samples exhibited RANTES as the only highly overexpressed cytokine. The FDOJ cohort with AFP/TRN showed a mean 30-fold overexpression of RANTES compared to healthy jawbones. Conclusions. To the best of our knowledge, no other research has identified RANTES overexpression in silent inflamed jawbones as a possible cause for AFP/TRN. Thus, we hypothesize that the surgical clearing of FDOJ might diminish RANTES signaling pathways in neurons and contribute to resolving chronic neurological pain in AFP/TRN patients.

  7. Biosynthesis of luminescent quantum dots in an earthworm

    Science.gov (United States)

    Stürzenbaum, S. R.; Höckner, M.; Panneerselvam, A.; Levitt, J.; Bouillard, J.-S.; Taniguchi, S.; Dailey, L.-A.; Khanbeigi, R. Ahmad; Rosca, E. V.; Thanou, M.; Suhling, K.; Zayats, A. V.; Green, M.

    2013-01-01

    The synthesis of designer solid-state materials by living organisms is an emerging field in bio-nanotechnology. Key examples include the use of engineered viruses as templates for cobalt oxide (Co3O4) particles, superparamagnetic cobalt-platinum alloy nanowires and gold-cobalt oxide nanowires for photovoltaic and battery-related applications. Here, we show that the earthworm's metal detoxification pathway can be exploited to produce luminescent, water-soluble semiconductor cadmium telluride (CdTe) quantum dots that emit in the green region of the visible spectrum when excited in the ultraviolet region. Standard wild-type Lumbricus rubellus earthworms were exposed to soil spiked with CdCl2 and Na2TeO3 salts for 11 days. Luminescent quantum dots were isolated from chloragogenous tissues surrounding the gut of the worm, and were successfully used in live-cell imaging. The addition of polyethylene glycol on the surface of the quantum dots allowed for non-targeted, fluid-phase uptake by macrophage cells.

  8. Semiconductor quantum-dot lasers and amplifiers

    DEFF Research Database (Denmark)

    Hvam, Jørn Märcher; Borri, Paola; Ledentsov, N. N.

    2002-01-01

    -power surface emitting VCSELs. We investigated the ultrafast dynamics of quantum-dot semiconductor optical amplifiers. The dephasing time at room temperature of the ground-state transition in semiconductor quantum dots is around 250 fs in an unbiased amplifier, decreasing to below 50 fs when the amplifier...... is biased to positive net gain. We have further measured gain recovery times in quantum dot amplifiers that are significantly lower than in bulk and quantum-well semiconductor optical amplifiers. This is promising for future demonstration of quantum dot devices with high modulation bandwidth...

  9. Batf3-dependent CD8α+ Dendritic Cells Aggravates Atherosclerosis via Th1 Cell Induction and Enhanced CCL5 Expression in Plaque Macrophages.

    Science.gov (United States)

    Li, Yalin; Liu, Xueyan; Duan, Wei; Tian, Hua; Zhu, Guangming; He, Hao; Yao, Shutong; Yi, Shuying; Song, Wengang; Tang, Hua

    2017-04-01

    Dendritic cells (DCs) play an important role in controlling T cell-mediated adaptive immunity in atherogenesis. However, the role of the basic leucine zipper transcription factor, ATF-like 3 (Batf3)-dependent CD8α + DC subset in atherogenesis remains unclear. Here we show that Batf3 -/- Apoe -/- mice, lacking CD8α + DCs, exhibited a significant reduction in atherogenesis and T help 1 (Th1) cells compared with Apoe -/- controls. Then, we found that CD8α + DCs preferentially induce Th1 cells via secreting interleukin-12 (IL-12), and that the expression of interferon-gamma (IFN-γ)or chemokine (C-C motif) ligand 5 (CCL5) in aorta were significantly decreased in Batf3 -/- Apoe -/- mice. We further demonstrated that macrophages were the major CCL5-expressing cells in the plaque, which was significantly reduced in Batf3 -/- Apoe -/- mice. Furthermore, we found CCL5 expression in macrophages was promoted by IFN-γ. Finally, we showed that Batf3 -/- Apoe -/- mice displayed decreased infiltration of leukocytes in the plaque. Thus, CD8α + DCs aggravated atherosclerosis, likely by inducing Th1 cell response, which promoted CCL5 expression in macrophages and increased infiltration of leukocytes and lesion inflammation. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  10. Transport properties of a Kondo dot with a larger side-coupled noninteracting quantum dot

    International Nuclear Information System (INIS)

    Liu, Y S; Fan, X H; Xia, Y J; Yang, X F

    2008-01-01

    We investigate theoretically linear and nonlinear quantum transport through a smaller quantum dot in a Kondo regime connected to two leads in the presence of a larger side-coupled noninteracting quantum dot, without tunneling coupling to the leads. To do this we employ the slave boson mean field theory with the help of the Keldysh Green's function at zero temperature. The numerical results show that the Kondo conductance peak may develop multiple resonance peaks and multiple zero points in the conductance spectrum owing to constructive and destructive quantum interference effects when the energy levels of the large side-coupled noninteracting dot are located in the vicinity of the Fermi level in the leads. As the coupling strength between two quantum dots increases, the tunneling current through the quantum device as a function of gate voltage applied across the two leads is suppressed. The spin-dependent transport properties of two parallel coupled quantum dots connected to two ferromagnetic leads are also investigated. The numerical results show that, for the parallel configuration, the spin current or linear spin differential conductance are enhanced when the polarization strength in the two leads is increased

  11. Assembling tin dioxide quantum dots to graphene nanosheets by a facile ultrasonic route.

    Science.gov (United States)

    Chen, Chen; Wang, Lijun; Liu, Yanyu; Chen, Zhiwen; Pan, Dengyu; Li, Zhen; Jiao, Zheng; Hu, Pengfei; Shek, Chan-Hung; Wu, C M Lawrence; Lai, Joseph K L; Wu, Minghong

    2013-03-26

    Nanocomposites have significant potential in the development of advanced materials for numerous applications. Tin dioxide (SnO2) is a functional material with wide-ranging prospects because of its high electronic mobility and wide band gap. Graphene as the basic plane of graphite is a single atomic layer two-dimensional sp(2) hybridized carbon material. Both have excellent physical and chemical properties. Here, SnO2 quantum dots/graphene composites have been successfully fabricated by a facile ultrasonic method. The experimental investigations indicated that the graphene was exfoliated and decorated with SnO2 quantum dots, which was dispersed uniformly on both sides of the graphene. The size distribution of SnO2 quantum dots was estimated to be ranging from 4 to 6 nm and their average size was calculated to be about 4.8 ± 0.2 nm. This facile ultrasonic route demonstrated that the loading of SnO2 quantum dots was an effective way to prevent graphene nanosheets from being restacked during the reduction. During the calcination process, the graphene nanosheets distributed between SnO2 nanoparticles have also prevented the agglomeration of SnO2 nanoparticles, which were beneficial to the formation of SnO2 quantum dots.

  12. 15 CFR 742.4 - National security.

    Science.gov (United States)

    2010-01-01

    ... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false National security. 742.4 Section 742.4... INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE EXPORT ADMINISTRATION REGULATIONS CONTROL POLICY-CCL BASED CONTROLS § 742.4 National security. (a) License requirements. It is the policy of the United States to...

  13. Sol-Gel Chemistry for Carbon Dots.

    Science.gov (United States)

    Malfatti, Luca; Innocenzi, Plinio

    2018-03-14

    Carbon dots are an emerging class of carbon-based nanostructures produced by low-cost raw materials which exhibit a widely-tunable photoluminescence and a high quantum yield. The potential of these nanomaterials as a substitute of semiconductor quantum dots in optoelectronics and biomedicine is very high, however they need a customized chemistry to be integrated in host-guest systems or functionalized in core-shell structures. This review is focused on recent advances of the sol-gel chemistry applied to the C-dots technology. The surface modification, the fine tailoring of the chemical composition and the embedding into a complex nanostructured material are the main targets of combining sol-gel processing with C-dots chemistry. In addition, the synergistic effect of the sol-gel precursor combined with the C-dots contribute to modify the intrinsic chemo-physical properties of the dots, empowering the emission efficiency or enabling the tuning of the photoluminescence over a wide range of the visible spectrum. © 2018 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Reducing pure dephasing of quantum bits by collective encoding in quantum dot arrays

    International Nuclear Information System (INIS)

    Grodecka, A; Machnikowski, P; Jacak, L

    2006-01-01

    We show that phonon-induced pure dephasing of an excitonic (charge) quantum bit in a quantum dot (QD) may be reduced by collective encoding of logical qubits in QD arrays. We define the logical qubit on an array of 2, 4 and 8 QDs, connecting the logical 0) state with the presence of excitons in the appropriately chosen half of dots and the logical 1) state with the other half of the dots occupied. We give quantitative estimates of the resulting total error of a single qubit operation for an InAs/GaAs system

  15. Large quantum dots with small oscillator strength

    DEFF Research Database (Denmark)

    Stobbe, Søren; Schlereth, T.W.; Höfling, S.

    2010-01-01

    We have measured the oscillator strength and quantum efficiency of excitons confined in large InGaAs quantum dots by recording the spontaneous emission decay rate while systematically varying the distance between the quantum dots and a semiconductor-air interface. The size of the quantum dots...... is measured by in-plane transmission electron microscopy and we find average in-plane diameters of 40 nm. We have calculated the oscillator strength of excitons of that size assuming a quantum-dot confinement given by a parabolic in-plane potential and a hard-wall vertical potential and predict a very large...... intermixing inside the quantum dots....

  16. Thermally oxidized formation of new Ge dots over as-grown Ge dots in the Si capping layer

    International Nuclear Information System (INIS)

    Nie Tianxiao; Lin Jinhui; Shao Yuanmin; Wu Yueqin; Yang Xinju; Fan Yongliang; Jiang Zuimin; Chen Zhigang; Zou Jin

    2011-01-01

    A Si-capped Ge quantum dot sample was self-assembly grown via Stranski-Krastanov mode in a molecular beam epitaxy system with the Si capping layer deposited at 300 deg. C. After annealing the sample in an oxygen atmosphere at 1000 deg. C, a structure, namely two layers of quantum dots, was formed with the newly formed Ge-rich quantum dots embedded in the oxidized matrix with the position accurately located upon the as-grown quantum dots. It has been found that the formation of such nanostructures strongly depends upon the growth temperature and oxygen atmosphere. A growth mechanism was proposed to explain the formation of the nanostructure based on the Ge diffusion from the as-grown quantum dots, Ge segregation from the growing oxide, and subsequent migration/agglomeration.

  17. Tailoring surface groups of carbon quantum dots to improve photoluminescence behaviors

    International Nuclear Information System (INIS)

    Tian, Ruixue; Hu, Shengliang; Wu, Lingling; Chang, Qing; Yang, Jinlong; Liu, Jun

    2014-01-01

    Highlights: • We develop a facile and green method to tailor surface groups. • Photoluminescence behaviors of carbon quantum dots are improved by tailoring their surface groups. • Highly luminescent efficiency is produced by amino-hydrothermal treatment of reduced carbon quantum dots. - Abstract: A facile and green method to tailor surface groups of carbon quantum dots (CQDs) is developed by hydrothermal treatment in an autoclave. The photoluminescence (PL) behaviors of CQDs depend on the types of surface groups. Highly efficient photoluminescence is obtained through amino-hydrothermal treatment of the CQDs reduced by NaBH 4 . The effects of surface groups on PL behavior are attributed to the degrees of energy band bending induced by surface groups

  18. Nano assembly of N-doped graphene quantum dots anchored Fe3O4/halloysite nanotubes for high performance supercapacitor

    International Nuclear Information System (INIS)

    Ganganboina, Akhilesh Babu; Chowdhury, Ankan Dutta; Doong, Ruey-an

    2017-01-01

    Highlights: •Halloysite coated Fe 3 O 4 is served as the framework for supporting graphene quantum dots. •GQDs can be well distributed onto Fe 3 O 4 /HNTs to prevent structural failure. •High specific capacitance of 418 F g −1 in 1 M Na 2 SO 4 neutral electrolyte is observed. •The composites show excellent electrochemical performance with energy density of 10.4–29.0 Wh kg −1 . -- Abstract: The development of robust and low cost electrode materials with superior electrochemical properties has been a subject of focus on energy storage devices. Herein, the development of N-doped graphene quantum dots (N-GQDs) deposited on Fe 3 O 4 -halloysite nanotubes (Fe 3 O 4 -HNTs) as active anode materials has been established for supercapacitor applications. The Fe 3 O 4 nanoparticles synthesised by coprecipitation have been in-situ deposited on HNT surfaces following by the coating of (3-aminopropyl)-triexthoxysilane to anchor 4–10 nm N-GQDs via the formation of amide linkage. The N-GQD@Fe 3 O 4 -HNTs exhibits a high specific capacitance of 418 F g −1 and maintains good rate capability in neutral electrolyte solutions. In addition, the anode materials show excellent electrochemical performance with energy and power densities of 10.4–29 W h kg −1 and 0.25–5.2 kW kg −1 , respectively. Such excellent electrochemical features can be attributed to the synergistic contribution from individual components. The Fe 3 O 4 -HNTs provide 1-dimensional matrix to shorten the diffusion path of electrons and electrolyte ions as well as to absorb the mechanical stress during cycling along with excess sites for charge storage, while N-GQDs offer abundantly accessible electroactive sites for rapid electrons and electrolyte ions transport as well as enhance electrical conductivity of Fe 3 O 4 -HNTs. Results obtained in this study clearly demonstrate that metal oxide-HNTs are promising support to anchor N-GQDs nanomaterials as the high performance anode materials for next

  19. An Evaluation of Treatment Outcomes in a Cohort of Clients on the DOTS Strategy, 2012-2016.

    Science.gov (United States)

    Tetteh, Ato Kwamena; Agyarko, Edward; Otchere, Joseph; Bimi, Langbong; Ayi, Irene

    2018-01-01

    We present, for the first time, an evaluation of treatment outcomes in a cohort at a TB referral centre in the Central Region of Ghana. Of the 213 clients placed on DOTS, 59.2% (126/213) were sputum smear-positive. An overall cure rate of 90.2% (51.6% cured + 37.6% completed) and a death rate of 8.5% (18/213) were estimated. Of the number of clients who died, 5.7% (12/213) were males ( χ 2 = 2.891, p = 0.699; LR = 3.004, p = 0.699). Deaths were only recorded among clients who were > 19 years old ( χ 2 = 40.319, p = 0.099; LR = 41.244, p = 0.083). Also, 0.9% (2/213) was lost to follow-up, while 1.4% (3/213) had treatment failure. In total, 13.6% (7.0%, 15/213 males, and 6.6%, 14/213 females) of clients who were placed on DOTS were HIV seropositive. Ages of 40-49 years had the highest number, 13/213 (6.1%), infected with HIV, though the difference among the remaining age groups was not statistically significant ( χ 2 = 9.621, p = 0.142). Furthermore, 7.0% (15/213) had TB/HIV coinfection. Out of them, 9 were cured and 5 died at home, while 1 had treatment failure. Tuberculosis/HIV infection prevention advocacy and interventions that address sociodemographic determinants of unfavourable treatment outcomes are urgently required to augment national efforts towards control.

  20. Optical properties of quantum-dot-doped liquid scintillators

    International Nuclear Information System (INIS)

    Aberle, C; Winslow, L; Li, J J; Weiss, S

    2013-01-01

    Semiconductor nanoparticles (quantum dots) were studied in the context of liquid scintillator development for upcoming neutrino experiments. The unique optical and chemical properties of quantum dots are particularly promising for the use in neutrinoless double-beta decay experiments. Liquid scintillators for large scale neutrino detectors have to meet specific requirements which are reviewed, highlighting the peculiarities of quantum-dot-doping. In this paper, we report results on laboratory-scale measurements of the attenuation length and the fluorescence properties of three commercial quantum dot samples. The results include absorbance and emission stability measurements, improvement in transparency due to filtering of the quantum dot samples, precipitation tests to isolate the quantum dots from solution and energy transfer studies with quantum dots and the fluorophore PPO