Sample records for lymphocyte atp content

  1. Extracellular ATP reduces HIV-1 transfer from immature dendritic cells to CD4+ T lymphocytes

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    Barat Corinne


    Full Text Available Abstract Background Dendritic cells (DCs are considered as key mediators of the early events in human immunodeficiency virus type 1 (HIV-1 infection at mucosal sites. Previous studies have shown that surface-bound virions and/or internalized viruses found in endocytic vacuoles of DCs are efficiently transferred to CD4+ T cells. Extracellular adenosine triphosphate (ATP either secreted or released from necrotic cells induces a distorted maturation of DCs, transiently increases their endocytic capacity and affects their migratory capacity. Knowing that high extracellular ATP concentrations are present in situations of tissue injury and inflammation, we investigated the effect of ATP on HIV-1 transmission from DCs to CD4+ T lymphocytes. Results In this study, we show that extracellular ATP reduces HIV-1 transfer from immature monocyte-derived DCs (iDCs to autologous CD4+ T cells. This observed decrease in viral replication was related to a lower proportion of infected CD4+ T cells following transfer, and was seen with both X4- and R5-tropic isolates of HIV-1. Extracellular ATP had no effect on direct CD4+ T cell infection as well as on productive HIV-1 infection of iDCs. These observations indicate that extracellular ATP affects HIV-1 infection of CD4+ T cells in trans with no effect on de novo virus production by iDCs. Additional experiments suggest that extracellular ATP might modulate the trafficking pathway of internalized virions within iDCs leading to an increased lysosomal degradation, which could be partly responsible for the decreased HIV-1 transmission. Conclusion These results suggest that extracellular ATP can act as a factor controlling HIV-1 propagation.

  2. Measurement of T-lymphocyte responses in whole-blood cultures using newly synthesized DNA and ATP. (United States)

    Sottong, P R; Rosebrock, J A; Britz, J A; Kramer, T R


    The proliferative response is most frequently determined by estimating the amount of [(3)H]thymidine incorporated into newly synthesized DNA. The [(3)H]thymidine procedure requires the use of radioisotopes as well as lengthy periods of incubation (>72 h). An alternative method of assessing T-lymphocyte activation in whole-blood cultures involves the measurement of the nucleotide ATP instead of [(3)H]thymidine incorporation. In addition, the Luminetics assay of T-cell activation measures specific T-lymphocyte subset responses through the use of paramagnetic particles coated with monoclonal antibodies against CD antigens. This assay permits rapid (24 h) analysis of lymphocyte subset activation responses to mitogens and recall antigens in small amounts of blood.

  3. Plasma ATP concentration and venous oxygen content in the forearm during dynamic handgrip exercise

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    Askew Christopher D


    Full Text Available Abstract Background It has been proposed that adenosine triphosphate (ATP released from red blood cells (RBCs may contribute to the tight coupling between blood flow and oxygen demand in contracting skeletal muscle. To determine whether ATP may contribute to the vasodilatory response to exercise in the forearm, we measured arterialised and venous plasma ATP concentration and venous oxygen content in 10 healthy young males at rest, and at 30 and 180 seconds during dynamic handgrip exercise at 45% of maximum voluntary contraction (MVC. Results Venous plasma ATP concentration was elevated above rest after 30 seconds of exercise (P Conclusions Collectively these results indicate that ATP in the plasma originated from the muscle microcirculation, and are consistent with the notion that deoxygenation of the blood perfusing the muscle acts as a stimulus for ATP release. That ATP concentration was elevated just 30 seconds after the onset of exercise also suggests that ATP may be a contributing factor to the blood flow response in the transition from rest to steady state exercise.

  4. Effect of UV-B irradiance on the ATP content of microorganisms of the Weddell Sea (Antartica)

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    Vosjan, J.H.; Nieuwland, G. (Netherlands Inst. for Sea Research, Den Burg (Netherlands)); Doehler, G. (Frankfurt Universitaet (Federal Republic of Germany). Botanisches Institut)


    The effect of UV-B irradiation on the ATP content of natural assemblages of planktonic microorganisms in the upper 30-m water layer of the Weddell Sea (Antartica) was studied. After five hours of irradiation with UV (290-320 nm) of 1.35 W.m{sup -2} a 75% decrease in the ATP content of the microorganisms was observed. (author). 11 refs.; 3 figs.

  5. Effect of UV-B irradiance on the ATP content of microorganisms of the Weddell Sea (Antartica)

    International Nuclear Information System (INIS)

    Vosjan, J.H.; Nieuwland, G.; Doehler, G.


    The effect of UV-B irradiation on the ATP content of natural assemblages of planktonic microorganisms in the upper 30-m water layer of the Weddell Sea (Antartica) was studied. After five hours of irradiation with UV (290-320 nm) of 1.35 W.m -2 a 75% decrease in the ATP content of the microorganisms was observed. (author). 11 refs.; 3 figs

  6. Lymphocyte subset contents in cerebrospinal fluid of children with viral encephalitis

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    An-Ran Xu


    Full Text Available Objective: To study the lymphocyte subset contents in cerebrospinal fluid of children with viral encephalitis and their correlation with disease. Methods: Children with viral encephalitis were selected as VE group, children excluded of central nervous system infection by lumbar puncture or children without central nervous system diseases but receiving surgery with spinal anesthesia were selected as control group, and then cerebrospinal fluid and serum were collected to detect lymphocyte subset contents, nerve injury molecule contents as well as inflammatory response indicators and oxidative stress response indicators. Results: CD3+, CD3+CD4+, CD4/CD8 and CD16+CD56+ in cerebrospinal fluid of VE group were lower than those of control group, and both CD3+CD8+ and CD19+ were higher than those of control group; CD3+, CD3+CD4+, CD4/CD8 and CD16+CD56+ in cerebrospinal fluid of children with abnormal MRI were lower than those of children with normal MRI, and both CD3+CD8+ and CD19+ were higher than those of children with normal MRI; NSE, MBP, S-100 and NPT contents in cerebrospinal fluid and serum of VE group were significantly higher than those of control group and had good correlation with lymphocyte subset contents; MMP9, TNF-α and IL-6 contents in cerebrospinal fluid of VE group were significantly higher than those of control group, and SOD and GSH-Px contents were significantly lower than those of control group and had good correlation with lymphocyte subset contents. Conclusions: CD4+/CD8+T lymphocyte ratio and NK cell content decrease, and B lymphocyte content increases in cerebrospinal fluid of children with viral encephalitis, and lymphocyte subset contents have inhibitory effect on MRI manifestation, degree of inflammatory response and oxidative stress response.


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    M. V. Peshikova


    Full Text Available Abstract. The aim of the present work was to evaluate the contents of some lymphocyte sub-populations in peripheral blood of the children with tumors of hematopoietic and lymphoid tissues, depending on infectious complication of cytostatic therapy and neutropenia. In all children undergoing cytostatic therapy for acute lympho-blastic leukemia and non-B cell non-Hodgkinґs lymphomas, we found significant decrease in the numbers of CD95 lymphocytes, absolute amounts of natural killer cells (CD16, CD56-lymphocytes and activated lymphocytes (СD11b, HLA-DR-cells, irrespective of neutrophile numbers in their blood and infectious complications. However, absolute number of CD25- lymphocytes was significantly decreased in the children with neutropenia. Relative contents of CD16, CD56, СD11b, HLA-DR, CD25-lymphocytes did not significantly differ from those in healthy children, or they were found to be significantly increased.

  8. Characterization and evaluation of a modified local lymph node assay using ATP content as a non-radio isotopic endpoint. (United States)

    Idehara, Kenji; Yamagishi, Gaku; Yamashita, Kunihiko; Ito, Michio


    The murine local lymph node assay (LLNA) is an accepted and widely used method for assessing the skin-sensitizing potential of chemicals. Here, we describe a non-radio isotopic modified LLNA in which adenosine triphosphate (ATP) content is used as an endpoint instead of radioisotope (RI); the method is termed LLNA modified by Daicel based on ATP content (LLNA-DA). Groups of female CBA/JNCrlj mice were treated topically on the dorsum of both ears with test chemicals or a vehicle control on days 1, 2, and 3; an additional fourth application was conducted on day 7. Pretreatment with 1% sodium lauryl sulfate solution was performed 1 h before each application. On day 8, the amount of ATP in the draining auricular lymph nodes was measured as an alternative endpoint by the luciferin-luciferase assay in terms of bioluminescence (relative light units, RLU). A stimulation index (SI) relative to the concurrent vehicle control was derived based on the RLU value, and an SI of 3 was set as the cut-off value. Using the LLNA-DA method, 31 chemicals were tested and the results were compared with those of other test methods. The accuracy of LLNA-DA vs LLNA, guinea pig tests, and human tests was 93% (28/30), 80% (20/25), and 79% (15/19), respectively. The estimated concentration (EC) 3 value was calculated and compared with that of the original LLNA. It was found that the EC3 values obtained by LLNA-DA were almost equal to those obtained by the original LLNA. The SI value based on ATP content is similar to that of the original LLNA as a result of the modifications in the chemical treatment procedure, which contribute to improving the SI value. It is concluded that LLNA-DA is a promising non-RI alternative method for evaluating the skin-sensitizing potential of chemicals.

  9. Differences in semen freezability and intracellular ATP content between the rooster (Gallus gallus domesticus) and the Barbary partridge (Alectoris barbara). (United States)

    Madeddu, M; Berlinguer, F; Pasciu, V; Succu, S; Satta, V; Leoni, G G; Zinellu, A; Muzzeddu, M; Carru, C; Naitana, S


    This study aimed to compare viability, ATP content, and DNA integrity of rooster (Gallus gallus domesticus) and Barbary partridge (Alectoris barbara) fresh and frozen spermatozoa in order to identify factors possibly related to differences in semen freezability. Ejaculates were obtained from March to May by the abdominal massage method from 3 adult roosters and 12 adult Barbary partridges. Semen was frozen with different cryoprotectants using Lake's diluents as a base medium: 1) glycerol 11%; 2) glycerol 11% and trehalose 70 mmol/L; 3) dimethylacetamide (DMA) 6%; 4) DMA 6% and trehalose 70 mmol/L. Both fresh and frozen semen showed a lower viability and higher intracellular ATP concentrations in the Barbary partridge compared with the rooster (P rooster a higher viability was recorded when semen was frozen in glycerol containing media compared to DMA (P rooster DNA fragmentation was higher in DMA ctr medium compared with the other media and with values found in Barbary partridge semen frozen in the same medium (P rooster and the Barbary partridge and the wide variation observed in ATP levels may account for differences in semen freezability between the two species. (c) 2010 Elsevier Inc. All rights reserved.

  10. Addition of granulosa cell mass to the culture medium of oocytes derived from early antral follicles increases oocyte growth, ATP content, and acetylation of H4K12. (United States)

    Sugiyama, Miyako; Sumiya, Mei; Shirasuna, Koumei; Kuwayama, Takehito; Iwata, Hisataka


    The main aim of the present study was to examine the hypothesis that an increase in the number of granulosa cells surrounding developing bovine oocytes results in both high ATP levels and an increase in the acetylation level of H4K12 in oocytes grown in vitro. Oocyte-granulosa cell complexes (OGCs) were collected from early antral follicles (EAFs, 0.4-0.7 mm in diameter), and individually cultured on 96-well plates with or without additional granulosa cell mass that had been prepared from other OGCs. After 16 days of culture, we examined: (i) the rate of antrum formation of the OGCs; (ii) the diameter, maturation, and fertilization rate of the oocytes; and (iii) the ATP content and acetylation level of H4K12 in the oocytes grown in vitro. Granulosa cell mass added to the culture medium contributed to the development of OGCs with a higher rate of antrum formation and oocyte growth. Furthermore, the addition of granulosa cells increased the ATP content and acetylation level of H4K12 in oocytes grown in vitro compared with those developed without addition of granulosa cells. In addition, there was a positive correlation between the ATP content in oocytes grown in vitro and the number of granulosa cells in the corresponding OGCs. The results suggest that granulosa cells play a role not only in the development of OGCs and the growth of oocytes, but also in the determination of ATP content and the acetylation of H4K12 in the oocytes developed in vitro.

  11. ATP signals

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    Novak, Ivana


    The Department of Biology at the University of Copenhagen explains the function of ATP signalling in the pancreas......The Department of Biology at the University of Copenhagen explains the function of ATP signalling in the pancreas...

  12. Properties of Na+ ,K+ -activated, Mg2+ -dependent ATP-hydrolyze of blood lymphocytes in patients with reаctive arthritis

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    O.V. Melnyk


    with RеA. We observed that Na+,K+-ATPase of peripheral blood lymphocytes of patients with RеA retains its endogenous receptor properties – sensitivity to ouabain does not change. It is assumed that under conditions of rheumatic pathology the impact on the Na+,K+-ATPase structure occurs both externally and on the cytoplasmic membrane surface. The above experimental data can be used for further clarification of the membrane mechanisms of ion exchange in immunocompetent cells of patients suffering from autoimmune diseases.

  13. Defective G2 repair in Down syndrome; Effect of caffeine, adenosine and niacinamide in control and X-ray irradiated lymphocytes

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    Pincheira, J.; Rodriguez, M. (Department of Cellular Biology and Genetics, University of Chile, Santiago (Chile)); Bravo, M. (Department of Pediatrics, University of Chile, Santiago (Chile)); Navarrete, M.H.; Lopez-Saez, J.F. (Department of Biology, Faculty of Science, Universidad Autonoma y CCIC, Madrid (Spain))


    Lymphocytes from both Down syndrome (DS) patients and age-matched control donors have been investigated to identify a possible disturbance in chromosomal G2 repair. Analyses of caffeine treatments during G2 have shown that the frequency of chromosomal aberrations is higher in DS lymphocytes than in normal lymphocytes. Likewise, G2 duration is longer in DS cells than in normal cells. In both control and DS lymphocytes, caffeine treatments increase the frequencies of chromatid breakages and decrease the average of G2 duration. The reversal of the caffeine potentiation effect by adenosine and niacinamide is higher in DS cells than in normal cells. Furthermore, ATP content per cell in DS lymphocytes is one third of that estimated in normal lymphocytes. The increase of ATP level produced by adenosine or niacinamide generally correlates with the reversal of the caffeine effect on chromosome aberrations. Under the experimental conditions tested, a good negative exponential correlation between ATP level and chromosome aberrations has been detected in both normal and DS lymphocytes which were or were not X-irradiated. Finally, we postulate a decrease in G2 repair capability of DS lymphocytes caused by a low availability of ATP and/or some other factor correlating with it. (au).

  14. Effects of rare earth and acid rain pollution on plant chloroplast ATP synthase and element contents at different growth stages. (United States)

    Zhang, Fan; Hu, Huiqing; Wang, Lihong; Zhou, Qing; Huang, Xiaohua


    Combined rare earth and acid rain pollution has become a new environmental problem, seriously affecting plant survival. The effects of these two kinds of pollutants on plant photosynthesis have been reported, but the micro mechanisms are not very clear. In this research, we studied the effects of lanthanum [La(III), 0.08, 1.20 and 2.40 mM] and acid rain (pH value = 2.5, 3.5 and 4.5) on the ATPase activity and gene transcription level and the functional element contents in rice leaf chloroplasts. The results showed that the combined 0.08 mM La(III) and pH 4.5 acid rain increased the ATPase activity and gene transcription level as well as contents of some functional elements. But other combined treatments of acid rain and La(III) reduced the ATPase activity and gene transcription level as well as functional element contents. The change magnitude of the above indexes at rice booting stage was greater than that in seedling stage or grain filling stage. These results reveal that effects of La(III) and acid rain on ATPase activity and functional element contents in rice leaf chloroplasts are related to the combination of La(III) dose and acid rain intensity and the plant growth stage. In addition, the changes in the ATPase activity were related to ATPase gene transcription level. This study would provide a reference for understanding the microcosmic mechanism of rare earth and acid rain pollution on plant photosynthesis and contribute to evaluate the possible environmental risks associated with combined La(III) and acid rain pollution. The effects of La(III) and acid rain on activity and gene transcription level of rice chloroplast ATPase and contents of functional elements were different at different growth stages. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Celecoxib and Ibuprofen Restore the ATP Content and the Gluconeogenesis Activity in the Liver of Walker-256 Tumor-Bearing Rats

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    Camila Oliveira de Souza


    Full Text Available Background/Aims: The main purpose of this study was to investigate the effects of celecoxib and ibuprofen, both non-steroidal anti-inflammatory drugs (NSAIDs, on the decreased gluconeogenesis observed in liver of Walker-256 tumor-bearing rats. Methods: Celecoxib and ibuprofen (both at 25 mg/Kg were orally administered for 12 days, beginning on the same day when the rats were inoculated with Walker-256 tumor cells. Results: Celecoxib and ibuprofen treatment reversed the reduced production of glucose, pyruvate, lactate and urea from alanine as well as the reduced production of glucose from pyruvate and lactate in perfused liver from tumor-bearing rats. Besides, celecoxib and ibuprofen treatment restored the decreased ATP content, increased triacylglycerol levels and reduced mRNA expression of carnitine palmitoyl transferase 1 (CPT1, while ibuprofen treatment restored the reduced mRNA expression of peroxisome proliferator-activated receptor alpha (PPARα in the liver of tumor-bearing rats. Both treatments tended to decrease TNFα, IL6 and IL10 in the liver of tumor-bearing rats. Finally, the treatment with celecoxib, but not with ibuprofen, reduced the growth of Walker-256 tumor. Conclusion: Celecoxib and ibuprofen restored the decreased gluconeogenesis in the liver of Walker-256 tumor-bearing rats. These effects did not involve changes in tumor growth and probably occurred by anti-inflammatory properties of these NSAIDs, which increased expression of genes associated with fatty acid oxidation (PPARα and CPT1 and consequently the ATP production, normalizing the energy status in the liver of tumor-bearing rats.

  16. Optimisation of ATP determination in drinking water

    DEFF Research Database (Denmark)

    Corfitzen, Charlotte B.; Albrechtsen, Hans-Jørgen

    Adenosine Triphosphate (ATP) can be used as a relative measure of cell activity, and is measured by the light output from the reaction between luciferin and ATP catalyzed by firefly luciferase. The measurement has potential as a monitoring and surveillance tool within drinking water distribution,...... be separated from the water phase by filtration.......Adenosine Triphosphate (ATP) can be used as a relative measure of cell activity, and is measured by the light output from the reaction between luciferin and ATP catalyzed by firefly luciferase. The measurement has potential as a monitoring and surveillance tool within drinking water distribution...... and an Advance Coupe luminometer. The investigations showed a 60 times higher response of the PCP-kit, making it more suitable for measurement of samples with low ATP content. ATP-standard dilutions prepared in tap water were stable for at least 15 months when stored frozen at -80ºC, and storage of large...

  17. Curcumin attenuates Cr(VI)-induced ascites and changes in the activity of aconitase and F(1)F(0) ATPase and the ATP content in rat liver mitochondria. (United States)

    García-Niño, Wylly Ramsés; Zazueta, Cecilia; Tapia, Edilia; Pedraza-Chaverri, José


    Occupational and environmental exposure to potassium dichromate (K2Cr2O7), a hexavalent chromium compound, can result in liver damage associated with oxidative stress and mitochondrial dysfunction. The purpose of this study was to evaluate the effect of the antioxidant curcumin (400 mg/kg b.w.) on the K2Cr2O7-induced injury, with special emphasis on ascitic fluid accumulation and oxidative phosphorylation mitochondrial enzymes and the adenosine triphosphate (ATP) levels in isolated mitochondria from livers of rats treated with K2Cr2O7 (15 mg/kg b.w.). Thus, curcumin attenuated the ascites generation, prevented the decrease in the activities of aconitase and F1F0 ATPase, and maintained the ATP levels. The activity of complex II was not completely reestablished by curcumin, whereas complexes III and IV activities were unchanged. © 2014 Wiley Periodicals, Inc.

  18. ATP Release Channels

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    Akiyuki Taruno


    Full Text Available Adenosine triphosphate (ATP has been well established as an important extracellular ligand of autocrine signaling, intercellular communication, and neurotransmission with numerous physiological and pathophysiological roles. In addition to the classical exocytosis, non-vesicular mechanisms of cellular ATP release have been demonstrated in many cell types. Although large and negatively charged ATP molecules cannot diffuse across the lipid bilayer of the plasma membrane, conductive ATP release from the cytosol into the extracellular space is possible through ATP-permeable channels. Such channels must possess two minimum qualifications for ATP permeation: anion permeability and a large ion-conducting pore. Currently, five groups of channels are acknowledged as ATP-release channels: connexin hemichannels, pannexin 1, calcium homeostasis modulator 1 (CALHM1, volume-regulated anion channels (VRACs, also known as volume-sensitive outwardly rectifying (VSOR anion channels, and maxi-anion channels (MACs. Recently, major breakthroughs have been made in the field by molecular identification of CALHM1 as the action potential-dependent ATP-release channel in taste bud cells, LRRC8s as components of VRACs, and SLCO2A1 as a core subunit of MACs. Here, the function and physiological roles of these five groups of ATP-release channels are summarized, along with a discussion on the future implications of understanding these channels.

  19. (/sup 3/H)ouabain binding to leukaemic cells and intralymphocytic sodium content in chronic lymphocytic leukaemia; no evidence for alterations of the Na/sup +//K/sup +/-pump

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    Berntorp, E; Berntorp, K


    The number of specific (/sup 3/H)ouabain binding sites and dissociation constants (K/sub d/) were determined by Scatchard analysis of values for leucocytes from patients with B-cell chronic lymphocytic leukaemia (CCL), chronic myeloid leukaemia (CML), acute blastic leukaemia (AL) and healthy subjects. CCL lymphocytes and normal B-cells bound significantly less (/sup 3/H)ouabain than did normal T-lymphocytes. CML granulocytes showed the same binding characteristics as normal granulocytes, while blast cells from AL patients bound significantly more (/sup 3/H)ouabain than did normal granulocytes or B-cells. The increased binding capacity in blast cells might, at least partly, reflect their larger cell size. A decrease in K/sub d/ values was only found in CLL lymphocytes, as compared with normal B-cells. Intralymphocytic sodium content in CLL lymphocytes was significantly increased, as sompared with that in T-cell-enriched normal lymphocytes. (/sup 3/H)ouabain binding did not show any relationship to different prognostic variables in CLL. The present data mainly argue against altered Na/sup +//K/sup +/-ATPase enzyme activity as an indicator of malignancy.

  20. Glycolysis and ATP degradation in cod ( Gadus morhua ) at subzero temperatures in relation to thaw rigor

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    Cappeln, Gertrud; Jessen, Flemming


    Glycolysis was shown to occur during freezing of cod of decrease in glycogen and an increase in lactate. In addition, the ATP content decreased during freezing. Synthesis of ATP was measured as degradation of glycogen. During storage at -9 and - 12 degreesC it was found that degradation of ATP...

  1. Content

    DEFF Research Database (Denmark)

    Keiding, Tina Bering

    secondary levels. In subject matter didactics, the question of content is more developed, but it is still mostly confined to teaching on lower levels. As for higher education didactics, discussions on selection of content are almost non-existent on the programmatic level. Nevertheless, teachers are forced...... curriculum, in higher education, and to generate analytical categories and criteria for selection of content, which can be used for systematic didactical reflection. The larger project also concerns reflection on and clarification of the concept of content, including the relation between content at the level......Aim, content and methods are fundamental categories of both theoretical and practical general didactics. A quick glance in recent pedagogical literature on higher education, however, reveals a strong preoccupation with methods, i.e. how teaching should be organized socially (Biggs & Tang, 2007...

  2. ATP Release from Human Airway Epithelial Cells Exposed to Staphylococcus aureus Alpha-Toxin

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    Romina Baaske


    Full Text Available Airway epithelial cells reduce cytosolic ATP content in response to treatment with S. aureus alpha-toxin (hemolysin A, Hla. This study was undertaken to investigate whether this is due to attenuated ATP generation or to release of ATP from the cytosol and extracellular ATP degradation by ecto-enzymes. Exposure of cells to rHla did result in mitochondrial calcium uptake and a moderate decline in mitochondrial membrane potential, indicating that ATP regeneration may have been attenuated. In addition, ATP may have left the cells through transmembrane pores formed by the toxin or through endogenous release channels (e.g., pannexins activated by cellular stress imposed on the cells by toxin exposure. Exposure of cells to an alpha-toxin mutant (H35L, which attaches to the host cell membrane but does not form transmembrane pores, did not induce ATP release from the cells. The Hla-mediated ATP-release was completely blocked by IB201, a cyclodextrin-inhibitor of the alpha-toxin pore, but was not at all affected by inhibitors of pannexin channels. These results indicate that, while exposure of cells to rHla may somewhat reduce ATP production and cellular ATP content, a portion of the remaining ATP is released to the extracellular space and degraded by ecto-enzymes. The release of ATP from the cells may occur directly through the transmembrane pores formed by alpha-toxin.

  3. Contents

    Directory of Open Access Journals (Sweden)

    Editor IJRED


    Full Text Available International Journal of Renewable Energy Development Volume 1             Number 3            October 2012                ISSN 2252- 4940   CONTENTS OF ARTICLES page Design and Economic Analysis of a Photovoltaic System: A Case Study 65-73 C.O.C. Oko , E.O. Diemuodeke, N.F. Omunakwe, and E. Nnamdi     Development of Formaldehyde Adsorption using Modified Activated Carbon – A Review 75-80 W.D.P Rengga , M. Sudibandriyo and M. Nasikin     Process Optimization for Ethyl Ester Production in Fixed Bed Reactor Using Calcium Oxide Impregnated Palm Shell Activated Carbon (CaO/PSAC 81-86 A. Buasri , B. Ksapabutr, M. Panapoy and N. Chaiyut     Wind Resource Assessment in Abadan Airport in Iran 87-97 Mojtaba Nedaei       The Energy Processing by Power Electronics and its Impact on Power Quality 99-105 J. E. Rocha and B. W. D. C. Sanchez       First Aspect of Conventional Power System Assessment for High Wind Power Plants Penetration 107-113 A. Merzic , M. Music, and M. Rascic   Experimental Study on the Production of Karanja Oil Methyl Ester and Its Effect on Diesel Engine 115-122 N. Shrivastava,  , S.N. Varma and M. Pandey  

  4. Effect of irradiation on detection of bacteria in dehydrated vegetables with ATP bioluminescence assay

    International Nuclear Information System (INIS)

    Xiao Huan; Luo Shishi; Wang Zegang; Feng Min; Zhu Jiating; Chen Xiulan; Zhai Jianqing


    ATP bioluminescence intensity of 4 kinds of irradiated dehydrated vegetables was inconsistent with the bacteria number, the reasons were investigated in this paper. Results showed that irradiation had little effect on background luminescence, and there was no effect on luciferase-luminous system. When irradiation killed the bacteria, the ATPase activity also decreased. As a result, the ATP content in bacteria didn't decreased with the killed of bacteria, which contributed to the increase of free ATP in ATP extract and finally led to the disagreement between the bioluminescence intensity and the actual number of bacteria. When the free ATP in the dehydrated vegetable was removed, the bioluminescence intensity of ATP extract was consistent with the actual number of bacteria in irradiated dehydrated vegetable and ATP bioluminescence technology could be used in bacteria detection of irradiated samples. (authors)

  5. Chronic lymphocytic leukemia (CLL) (United States)

    ... is used for painful and enlarged lymph nodes. Blood transfusions or platelet transfusions may be required if blood ... unexplained fatigue, bruising, excessive sweating, or weight loss. Alternative ... Leukemia - chronic lymphocytic (CLL); Blood cancer - chronic lymphocytic leukemia; Bone marrow cancer - chronic ...

  6. Degradation of ATP and glycogen in cod ( Gadus morhua ) muscle during freezing

    DEFF Research Database (Denmark)

    Cappeln, Gertrud; Jessen, Flemming


    Changes in ATP, IMP, lactate and glycogen contents in the muscle of cod were followed during freezing at temperatures of -20C and -45C. ATP degradation was accompanied by a corresponding increase in IMP content. Simultaneous measurement of temperature showed that at both freezing rates......, the greatest decrease in ATP content was observed when the temperature reached -0.8C. Glycolysis occurred during freezing of cod as indicated by an increase in lactate content. The changes found in all measured metabolites were more pronounced when freezing was performed at a slow rate compared to a fast rate...

  7. Effects of de-alcoholised wines with different polyphenol content on DNA oxidative damage, gene expression of peripheral lymphocytes, and haemorheology: an intervention study in post-menopausal women. (United States)

    Giovannelli, Lisa; Pitozzi, Vanessa; Luceri, Cristina; Giannini, Lucia; Toti, Simona; Salvini, Simonetta; Sera, Francesco; Souquet, Jean-Marc; Cheynier, Veronique; Sofi, Francesco; Mannini, Lucia; Gori, Anna Maria; Abbate, Rosanna; Palli, Domenico; Dolara, Piero


    Epidemiological studies suggest that a moderate consumption of wine is associated with a reduced risk of cardiovascular diseases and with a reduced mortality for all causes, possibly due to increased antioxidant defences. The present intervention study was undertaken to evaluate the in vivo effects of wine polyphenols on gene expression in humans, along with their supposed antioxidant activity. Blood haemorheology and platelet function were also evaluated. In order to avoid interferences from alcohol, we used de-alcoholised wine (DAW) with different polyphenol content. A randomised cross-over trial of high-proanthocyanidin (PA) red DAW (500 mL/die, PA dose = 7 mg/kg b.w.) vs. low-PA rosé DAW (500 mL/die, PA dose = 0.45 mg/kg) was conducted in 21 post-menopausal women in Florence, Italy. Oxidative DNA damage by the comet assay and gene expression by microarray was measured in peripheral blood lymphocytes, collected during the study period. Blood samples were also collected for the evaluation of haematological, haemostatic, haemorheological, and inflammatory parameters. The results of the present study provide evidence that consumption of substantial amounts of de-alcoholised wine for 1 month does not exert a protective activity towards oxidative DNA damage, nor modifies significantly the gene expression profile of peripheral lymphocytes, whereas it shows blood-fluidifying actions, expressed as a significant decrease in blood viscosity. However, this effect does not correlate with the dosage of polyphenols of the de-alcoholised wine. More intervention studies are needed to provide further evidence of the health-protective effects of wine proanthocyanidins.

  8. Radiation effects on lymphocytes

    International Nuclear Information System (INIS)

    Roser, B.


    This review of the ontogeny of lymphocyte populations concentrates on sites of production, rates of production, and the factors governing the differentiation and longevity of the various lymphocyte pools. The physiology of the lymphocyte pools is described with particular emphasis on recirculation from blood to lymph through lymphoid tissues. The separate routes of recirculation of both thymus-derived and nonthymus-derived lymphocytes and the possible anatomical sites and mechanisms of lymphocyte cooperation are discussed. Radiation effects on lymphocyte populations are divided into two sections. First, the effects of whole-body irradiation on the total lymphocyte pools are discussed including the differential effects of irradiation on T lymphocytes, B lymphocytes, lymphoblasts, and plasma cells. The differential sensitivity of various types of immune response is correlated, where possible, with the differential sensitivity of the lymphocyte types involved. Second, experimental attempts to selectively deplete discrete subpopulations of the total lymphocyte pools, e.g., recirculating cells, are briefly discussed with particular emphasis on studies on the effects of the localization of radionuclides in lymphoid tissue

  9. ATP synthesis is impaired in isolated mitochondria from myotubes established from type 2 diabetic subjects

    DEFF Research Database (Denmark)

    Minet, Ariane D; Gaster, Michael


    To date, it is unknown whether mitochondrial dysfunction in skeletal muscle from subjects with type 2 diabetes is based on primarily reduced mitochondrial mass and/or a primarily decreased mitochondrial ATP synthesis. Mitochondrial mass were determined in myotubes established from eight lean, eight...... mass and the ATP synthesis rate, neither at baseline nor during acute insulin stimulation, were not different between groups. The ratio of ATP synthesis rate at hexokinase versus ATP synthesis rate at baseline was lower in diabetic mitochondria compared to lean mitochondria. Thus the lower content...... obese and eight subjects with type 2 diabetes precultured under normophysiological conditions. Furthermore, mitochondria were isolated and ATP production was measured by luminescence at baseline and during acute insulin stimulation with or without concomitant ATP utilization by hexokinase. Mitochondrial...

  10. Biodistribution of radiolabeled lymphocytes

    International Nuclear Information System (INIS)

    Fawwaz, R.A.; Oluwole, S.; Wang, T.S.; Kuromoto, N.; Iga, C.; Hardy, M.A.; Alderson, P.O.


    Factors that might affect the biodistribution and clinical utility of radiolabeled lymphocytes were evaluated in experimental animals. Indium-111 (In-111) labeled lymphocytes obtained from peripheral blood, lymph node, or spleen were found in significant amounts in the lymphoid tissues of Lewis rats as early as 3 hours after infusion. A progressive increase in nodal activity with concomitant fall of activity in other organs followed, indicating active recirculation of the lymphocytes. In vitro irradiation of the In-111 labeled lymphocytes resulted in no detectable lymphocyte recirculation and/or reduced localization in lymphoid tissue. Splenectomized animals and those sensitized to an organ allograft before cell infusion showed increased activity in their bone marrow. These results suggest that the source of the injected cells, cell irradiation dose level and host sensitization should be considered when radiolabeled lymphocytes are being prepared for use in clinical diagnosis and therapy

  11. Extracellular ATP induces albuminuria in pregnant rats

    NARCIS (Netherlands)

    Faas, M.M.; van der Schaaf, G.; Borghuis, T.; Jongman, R.M.; van Pampus, Maria; de Vos, P.; van Goor, Harry; Bakker, W.W.

    BACKGROUND: As circulating plasma ATP concentrations are increased in pre-eclampsia, we tested whether increased plasma ATP is able to induce albuminuria during pregnancy. METHODS: Pregnant (day 14) and non-pregnant rats were infused with ATP (3000 microg/kg bw) via a permanent jugular vein cannula.

  12. ATP Release and Effects in Pancreas

    DEFF Research Database (Denmark)

    Novak, Ivana; Amstrup, Jan; Henriksen, Katrine Lütken


    ATP and other nucleotides are released from various cells, but the pathway and physiological stimulus for ATP release are often unclear. The focus of our studies is the understanding of ATP release and signaling in rat exocrine pancreas. In acinar suspension mechanical stimulation, hypotonic shock...

  13. Increased NTPDase Activity in Lymphocytes during Experimental Sepsis (United States)

    Bertoncheli, Claudia de Mello; Zimmermann, Carine Eloise Prestes; Jaques, Jeandre Augusto dos Santos; Leal, Cláudio Alberto Martins; Ruchel, Jader Betsch; Rocha, Bruna Cipolatto; Pinheiro, Kelly de Vargas; Souza, Viviane do Carmo Gonçalves; Stainki, Daniel Roulim; Luz, Sônia Cristina Almeida; Schetinger, Maria Rosa Chitolina; Leal, Daniela Bitencourt Rosa


    We investigated in rats induced to sepsis the activity of ectonucleoside triphosphate diphosphohydrolase (NTPDase; CD39; E.C., an enzyme involved in the modulation of immune responses. After 12 hours of surgery, lymphocytes were isolated from blood and NTPDase activity was determined. It was also performed the histology of kidney, liver, and lung. The results demonstrated an increase in the hydrolysis of adenosine-5′-triphosphate (ATP) (P 0.05). Histological analysis showed several morphological changes in the septic group, such as vascular congestion, necrosis, and infiltration of mononuclear cells. It is known that the intracellular milieu contains much more ATP nucleotides than the extracellular. In this context, the increased ATPasic activity was probably induced as a dynamic response to clean up the elevated ATP levels resulting from cellular death. PMID:22645477

  14. To the nucleolar bodies (nucleoli) in cells of the lymphocytic lineage in patients suffering from B - chronic lymphocytic leukemia. (United States)

    Smetana, K; Karban, J; Trneny, M


    The present study was undertaken to provide more information on nucleoli in lymphocytes of B - chronic lymphocytic leukemia. The computer assisted nucleolar and cytoplasmic RNA image densitometry, reflecting the nucleolar and cytoplasmic RNA concentration at the single cell level, demonstrated a remarkable stability during the differentiation and maturation of B- lymphocytes. In contrast, as it was expected, the nucleolar diameter during the lymphocytic development markedly decreased. Thus the nucleolar RNA content of leukemic B-lymphocytes was apparently related to the nucleolar size. In both immature and mature lymphocytes, the cytostatic treatment increased the incidence of micronucleoli, which represent the "inactive" type of nucleoli. However, the decreased values of the nucleolar diameter were statistically significant only in mature lymphocytes of treated patients. On the other hand, despite such observation, it must be mentioned that "large active" and "ring shaped resting" nucleoli were still present in immature and mature lymphocytes after the cytostatic therapy and such cells might represent a potential pool of proliferating cells. As it is generally accepted "large active nucleoli" with multiple fibrillar centers are known to be characteristic for proliferating cells. "Ring shaped resting nucleoli" are present in sleeping cells, which may be stimulated to return to the cell cycle and to proliferate again. In addition, the nucleolar RNA distribution also indicated that Gumprecht ghosts mostly originated from mature lymphocytes. Increased ratio of the nucleolar to cytoplasmic RNA density in Gumprecht ghosts or apoptotic cells and apoptotic bodies of the lymphocytic origin was related to the decreased cytoplasmic RNA concentration. The increased nucleolar size together with the markedly decreased cytoplasmic RNA concentration characteristic for Gumprecht ghosts just reflected the spreading of lymphocytes during smear preparations. In apoptotic cells or

  15. Biometric indices of recirculating lymphocytes after acute and chronic gamma-irradiation

    International Nuclear Information System (INIS)

    Kalinin, E.V.


    The karyometry method was used to study the distribution of mature lymphocytes of lymphatic organs and peripheral blood among classes of nuclear volumes. Radiation injury was accompanied by a selection of populations of short-lived lymphocytes with very big nuclei the content of which was function of cumulative radiation dose. The number of small lymphocytes dependend on the phase of the radiation reaction

  16. The effects of membrane cholesterol and simvastatin on red blood cell deformability and ATP release. (United States)

    Forsyth, Alison M; Braunmüller, Susanne; Wan, Jiandi; Franke, Thomas; Stone, Howard A


    It is known that deformation of red blood cells (RBCs) is linked to ATP release from the cells. Further, membrane cholesterol has been shown to alter properties of the cell membrane such as fluidity and bending stiffness. Membrane cholesterol content is increased in some cardiovascular diseases, for example, in individuals with acute coronary syndromes and chronic stable angina, and therefore, because of the potential clinical relevance, we investigated the influence of altered RBC membrane cholesterol levels on ATP release. Because of the correlation between statins and reduced membrane cholesterol in vivo, we also investigated the effects of simvastatin on RBC deformation and ATP release. We found that reducing membrane cholesterol increases cell deformability and ATP release. We also found that simvastatin increases deformability by acting directly on the membrane in the absence of the liver, and that ATP release was increased for cells with enriched cholesterol after treatment with simvastatin. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Sodium homeostasis in lymphocytes and blood pressure alterations before and during salt restriction in normotensives and in essential hypertensives

    DEFF Research Database (Denmark)

    Jest, P; Pedersen, K E; Klitgaard, N A


    Blood pressure, lymphocytic sodium content and sodium efflux were studied in hypertensive and normotensive subjects during salt restriction. Diastolic blood pressure decreased significantly in both groups. In essential hypertension the initial high lymphocyte sodium content decreased during salt...... mechanisms with regard to lymphocyte sodium metabolism differs between hypertensive and normotensive subjects....

  18. Diversity and regulation of ATP sulfurylase in photosynthetic organisms

    Directory of Open Access Journals (Sweden)

    Laura ePrioretti


    Full Text Available ATP sulfurylase (ATPS catalyzes the first committed step in the sulfate assimilation pathway, the activation of sulfate prior to its reduction. ATPS has been studied in only a few model organisms and even in these cases to a much smaller extent than the sulfate reduction and cysteine synthesis enzymes. This is possibly because the latter were considered of greater regulatory importance for sulfate assimilation. Recent evidences (reported in this paper challenge this view and suggest that ATPSes may have a crucial regulatory role in sulfate assimilation, at least in algae.In the ensuing text, we summarize the current knowledge on ATPS, with special attention to the processes that control its activity and gene(s expression. Special attention is given to algae ATPSes. The focus on algae is the consequence of the fact that a comprehensive investigation of ATPSes revealed that the algal enzymes, especially those that are most likely involved in the pathway of sulfate reduction to cysteine, possess features that are not present in other organisms. For instance, algae ATPSes show a great diversity of isoforms and a high content of cysteine residues, whose positions are often conserved. It is interesting that, at least with respect to the number of cysteines, the ATPSes of eukaryotic algae are closer to the marine cyanobacteria of the genera Synechococcus and Prochlorococcus and are more distant from freshwater cyanobacteria. These characteristics might have evolved in parallel with the radiation of algae in the oceans and the increase of sulfate concentration in seawater.

  19. Optimization of ATP synthase function in mitochondria and chloroplasts via the adenylate kinase equilibrium

    Directory of Open Access Journals (Sweden)

    Abir U Igamberdiev


    Full Text Available The bulk of ATP synthesis in plants is performed by ATP synthase, the main bioenergetics engine of cells, operating both in mitochondria and in chloroplasts. The reaction mechanism of ATP synthase has been studied in detail for over half a century; however, its optimal performance depends also on the steady delivery of ATP synthase substrates and the removal of its products. For mitochondrial ATP synthase, we analyze here the provision of stable conditions for (i the supply of ADP and Mg2+, supported by adenylate kinase (AK equilibrium in the intermembrane space, (ii the supply of phosphate via membrane transporter in symport with H+, and (iii the conditions of outflow of ATP by adenylate transporter carrying out the exchange of free adenylates. We also show that, in chloroplasts, AK equilibrates adenylates and governs Mg2+ contents in the stroma, optimizing ATP synthase and Calvin cycle operation, and affecting the import of inorganic phosphate in exchange with triose phosphates. It is argued that chemiosmosis is not the sole component of ATP synthase performance, which also depends on AK-mediated equilibrium of adenylates and Mg2+, adenylate transport and phosphate release and supply.

  20. Mechanisms of constitutive and ATP-evoked ATP release in neonatal mouse olfactory epithelium

    Directory of Open Access Journals (Sweden)

    Hayoz Sébastien


    Full Text Available Abstract Background ATP is an extracellular signaling molecule with many ascribed functions in sensory systems, including the olfactory epithelium. The mechanism(s by which ATP is released in the olfactory epithelium has not been investigated. Quantitative luciferin-luciferase assays were used to monitor ATP release, and confocal imaging of the fluorescent ATP marker quinacrine was used to monitor ATP release via exocytosis in Swiss Webster mouse neonatal olfactory epithelial slices. Results Under control conditions, constitutive release of ATP occurs via exocytosis, hemichannels and ABC transporters and is inhibited by vesicular fusion inhibitor Clostridium difficile toxin A and hemichannel and ABC transporter inhibitor probenecid. Constitutive ATP release is negatively regulated by the ATP breakdown product ADP through activation of P2Y receptors, likely via the cAMP/PKA pathway. In vivo studies indicate that constitutive ATP may play a role in neuronal homeostasis as inhibition of exocytosis inhibited normal proliferation in the OE. ATP-evoked ATP release is also present in mouse neonatal OE, triggered by several ionotropic P2X purinergic receptor agonists (ATP, αβMeATP and Bz-ATP and a G protein-coupled P2Y receptor agonist (UTP. Calcium imaging of P2X2-transfected HEK293 “biosensor” cells confirmed the presence of evoked ATP release. Following purinergic receptor stimulation, ATP is released via calcium-dependent exocytosis, activated P2X1,7 receptors, activated P2X7 receptors that form a complex with pannexin channels, or ABC transporters. The ATP-evoked ATP release is inhibited by the purinergic receptor inhibitor PPADS, Clostridium difficile toxin A and two inhibitors of pannexin channels: probenecid and carbenoxolone. Conclusions The constitutive release of ATP might be involved in normal cell turn-over or modulation of odorant sensitivity in physiological conditions. Given the growth-promoting effects of ATP, ATP-evoked ATP

  1. Conformational dynamics of ATP/Mg:ATP in motor proteins via data mining and molecular simulation (United States)

    Bojovschi, A.; Liu, Ming S.; Sadus, Richard J.


    The conformational diversity of ATP/Mg:ATP in motor proteins was investigated using molecular dynamics and data mining. Adenosine triphosphate (ATP) conformations were found to be constrained mostly by inter cavity motifs in the motor proteins. It is demonstrated that ATP favors extended conformations in the tight pockets of motor proteins such as F1-ATPase and actin whereas compact structures are favored in motor proteins such as RNA polymerase and DNA helicase. The incorporation of Mg2+ leads to increased flexibility of ATP molecules. The differences in the conformational dynamics of ATP/Mg:ATP in various motor proteins was quantified by the radius of gyration. The relationship between the simulation results and those obtained by data mining of motor proteins available in the protein data bank is analyzed. The data mining analysis of motor proteins supports the conformational diversity of the phosphate group of ATP obtained computationally.

  2. Muscle interstitial ATP and norepinephrine concentrations in the human leg during exercise and ATP infusion

    DEFF Research Database (Denmark)

    Mortensen, Stefan P.; Gonzalez-Alonso, Jose; Nielsen, Jens Jung


    ATP and NE concentrations to gain insight into the interstitial and intravascular mechanisms by which ATP causes muscle vasodilation and sympatholysis. Leg hemodynamics and muscle interstitial nucleotide and norepinephrine (NE) concentrations were measured during: 1) femoral arterial ATP infusion (0......, respectively (Pcontracting muscle (Pmuscle, whereas interstitial NE concentrations increased similarly in both active...... and inactive muscles. These results suggest that the vasodilatory and sympatholytic effects of intraluminal ATP are mainly mediated via endothelial prinergic receptors. Intraluminal ATP and muscle contractions appear to modulate sympathetic nerve activity by inhibiting the effect of NE rather than blunting its...

  3. Chemokines, lymphocytes, and HIV

    Directory of Open Access Journals (Sweden)

    Farber J.M.


    Full Text Available Chemokines are members of a family of more than 30 human cytokines whose best-described activities are as chemotactic factors for leukocytes and that are presumed to be important in leukocyte recruitment and trafficking. While many chemokines can act on lymphocytes, the roles of chemokines and their receptors in lymphocyte biology are poorly understood. The recent discoveries that chemokines can suppress infection by HIV-1 and that chemokine receptors serve, along with CD4, as obligate co-receptors for HIV-1 entry have lent urgency to studies on the relationships between chemokines and lymphocytes. My laboratory has characterized Mig and Crg-2/IP-10, chemokines that are induced by IFN-g and that specifically target lymphocytes, particularly activated T cells. We have demonstrated that the genes for these chemokines are widely expressed during experimental infections in mice with protozoan and viral pathogens, but that the patterns of mig and crg-2 expression differed, suggesting non-redundant roles in vivo. Our related studies to identify new chemokine receptors from activated lymphocytes resulted in the cloning of STRL22 and STRL33. We and others have shown that STRL22 is a receptor for the CC chemokine MIP-3a, and STRL22 has been re-named CCR6. Although STRL33 remains an orphan receptor, we have shown that it can function as a co-receptor for HIV-1 envelope glycoproteins, and that it is active with a broader range of HIV-1 envelope glycoproteins than the major co-receptors described to date. The ability of STRL33 to function with a wide variety of envelope glycoproteins may become particularly important if therapies are instituted to block other specific co-receptors. We presume that investigations into the roles of chemokines and their receptors in lymphocyte biology will provide information important for understanding the pathogenesis of AIDS and for manipulating immune and inflammatory responses for clinical benefit

  4. Degradation of ATP and glycogen in cod ( Gadus morhua ) muscle during freezing

    DEFF Research Database (Denmark)

    Cappeln, Gertrud; Jessen, Flemming


    , the greatest decrease in ATP content was observed when the temperature reached -0.8C. Glycolysis occurred during freezing of cod as indicated by an increase in lactate content. The changes found in all measured metabolites were more pronounced when freezing was performed at a slow rate compared to a fast rate...

  5. Estimation of Viable Biomass In Wastewater And Activated Sludge By Determination of ATP, Oxygen Utilization Rate And FDA Hydrolysis

    DEFF Research Database (Denmark)

    Jørgensen, Poul-Erik; Eriksen, T.; Jensen, B.K.


    ATP content, oxygen utilization rate (OUR) and fluorescein diacetate (FDA) hydrolysis were tested for the ability to express the amount of viable biomass in wastewater and activated sludge. The relationship between biomass and these activity parameters was established in growth cultures made...... with biomass, while FDA hydrolysis in the sludge failed to show any such correlation. Conversion factors of 3 mg ATP/g dw, 300 mg O2/h g dw and 0.4 A/h (mg dw/ml) for ATP, OUR and FDA methods, respectively, were calculated. When the methods were applied for in situ determinations in four different wastewater...... plants, it was found that ATP content and respiration rate estimated viable biomass to range from 81 to 293 mg dw/g SS for raw wastewater and from 67 to 187 mg dw/g SS for activated sludge with a rather weak correlation between ATP and respiration measurements. The FDA hydrolysis estimated viable biomass...

  6. The behavior of pig lymphocyte populations in vivo

    International Nuclear Information System (INIS)

    Binns, R.M.; Licence, S.T.; Pabst, R.


    Lymphocyte migration provides the means of rapidly recognizing and responding to antigen and widely disseminating the resulting immune response. The porcine lymphoid system differs from that of man in structural inversion of lymph nodes and route of lymphocyte recirculation and the existence of two Peyer's patch types, one of which differs from the conventional pattern in structure, cell content and lack of lymphocyte traffic and in its regression in old age. Recirculating T and B lymphocytes enter and leave spleen and lymph nodes by the blood but Null cells do not; lymphocytes also migrate through nonlymphoid tissues. The lung is one such important site, with a small migration in and out of alveolar space and a large traffic associated with the blood vessel wall, predominantly involving T cells. Blood lymphocytes hardly traffic into the peritoneal cavity, yet major traffic of particulate material or cells is possible in this important site of abdominal defense, so often used for immunization, and follows a distinct, well defined route. Cells migrate out of subcutaneous tissue via the draining node. Lymphocytes are produced and emigrate into blood from labelled thymus. They differ in size and surface phenotype from both thymocytes and peripheral T cells. Lymphocytes also migrate from blood into most tissues. In most nonlymphoid tissues, entry relates to blood flow but in many lymphoid tissues it is an active process which differs in tempo and extent, eg, between different nodes and between the two Peyer's patch types

  7. Mutations in the Atp1p and Atp3p subunits of yeast ATP synthase differentially affect respiration and fermentation in Saccharomyces cerevisiae. (United States)

    Francis, Brian R; White, Karen H; Thorsness, Peter E


    ATP1-111, a suppressor of the slow-growth phenotype of yme1Delta lacking mitochondrial DNA is due to the substitution of phenylalanine for valine at position 111 of the alpha-subunit of mitochondrial ATP synthase (Atp1p in yeast). The suppressing activity of ATP1-111 requires intact beta (Atp2p) and gamma (Atp3p) subunits of mitochondrial ATP synthase, but not the stator stalk subunits b (Atp4p) and OSCP (Atp5p). ATP1-111 and other similarly suppressing mutations in ATP1 and ATP3 increase the growth rate of wild-type strains lacking mitochondrial DNA. These suppressing mutations decrease the growth rate of yeast containing an intact mitochondrial chromosome on media requiring oxidative phosphorylation, but not when grown on fermentable media. Measurement of chronological aging of yeast in culture reveals that ATP1 and ATP3 suppressor alleles in strains that contain mitochondrial DNA are longer lived than the isogenic wild-type strain. In contrast, the chronological life span of yeast cells lacking mitochondrial DNA and containing these mutations is shorter than that of the isogenic wild-type strain. Spore viability of strains bearing ATP1-111 is reduced compared to wild type, although ATP1-111 enhances the survival of spores that lacked mitochondrial DNA.

  8. Acute Lymphocytic Leukemia (United States)

    ... that may increase the risk of acute lymphocytic leukemia include: Previous cancer treatment. Children and adults who've had certain types of chemotherapy and radiation therapy for other kinds of cancer may have an increased ... leukemia. Exposure to radiation. People exposed to very high ...

  9. Metal-dependent regulation of ATP7A and ATP7B in fibroblast cultures

    Directory of Open Access Journals (Sweden)

    Lenartowicz Malgorzata


    Full Text Available Deficiency of one of the copper transporters ATP7A and ATP7B leads to the rare X-linked disorder Menkes Disease (MD or the rare autosomal disorder Wilson disease (WD, respectively. In order to investigate whether the ATP7A and the ATP7B genes may be transcriptionally regulated, we measured the expression level of the two genes at various concentrations of iron, copper and insulin. Treating fibroblasts from controls or from individuals with MD or WD for 3 and10 days with iron chelators revealed that iron deficiency led to increased transcript levels of both ATP7A and ATP7B. Copper deficiency obtained by treatment with the copper chelator led to a downregulation of ATP7A in the control fibroblasts, but surprisingly not in the WD fibroblasts. In contrast, the addition of copper led to an increased expression of ATP7A, but a decreased expression of ATP7B. Thus, whereas similar regulation patterns for the two genes were observed in response to iron deficiency, different responses were observed after changes in the access to copper. Mosaic fibroblast cultures from female carriers of MD treated with copper or copper chelator for 6-8 weeks led to clonal selection. Cells that express the normal ATP7A allele had a selective growth advantage at high copper concentrations, whereas more surprisingly, cells that express the mutant ATP7A allele had a selective growth advantage at low copper concentrations. Thus, although the transcription of ATP7A is regulated by copper, clonal growth selection in mosaic cell cultures is affected by the level of copper. Female carriers of MD are rarely affected probably due to a skewed inactivation of the X-chromosome bearing the ATP7A mutation.

  10. Effects and mechanism of acid rain on plant chloroplast ATP synthase. (United States)

    Sun, Jingwen; Hu, Huiqing; Li, Yueli; Wang, Lihong; Zhou, Qing; Huang, Xiaohua


    Acid rain can directly or indirectly affect plant physiological functions, especially photosynthesis. The enzyme ATP synthase is the key in photosynthetic energy conversion, and thus, it affects plant photosynthesis. To clarify the mechanism by which acid rain affects photosynthesis, we studied the effects of acid rain on plant growth, photosynthesis, chloroplast ATP synthase activity and gene expression, chloroplast ultrastructure, intracellular H(+) level, and water content of rice seedlings. Acid rain at pH 4.5 remained the chloroplast structure unchanged but increased the expression of six chloroplast ATP synthase subunits, promoted chloroplast ATP synthase activity, and increased photosynthesis and plant growth. Acid rain at pH 4.0 or less decreased leaf water content, destroyed chloroplast structure, inhibited the expression of six chloroplast ATP synthase subunits, decreased chloroplast ATP synthase activity, and reduced photosynthesis and plant growth. In conclusion, acid rain affected the chloroplast ultrastructure, chloroplast ATPase transcription and activity, and P n by changing the acidity in the cells, and thus influencing the plant growth and development. Finally, the effects of simulated acid rain on the test indices were found to be dose-dependent.

  11. ATP, IMP, and glycogen in cod muscle at onset and during development of rigor mortis depend on the sampling location

    DEFF Research Database (Denmark)

    Cappeln, Gertrud; Jessen, Flemming


    Variation in glycogen, ATP, and IMP contents within individual cod muscles were studied in ice stored fish during the progress of rigor mortis. Rigor index was determined before muscle samples for chemical analyzes were taken at 16 different positions on the fish. During development of rigor......, the contents of glycogen and ATP decreased differently in relation to rigor index depending on sampling location. Although fish were considered to be in strong rigor according to the rigor index method, parts of the muscle were not in rigor as high ATP concentrations were found in dorsal and tall muscle....

  12. Redox regulation of ATP sulfurylase in microalgae

    Czech Academy of Sciences Publication Activity Database

    Prioretti, L.; Lebrun, R.; Gontero, B.; Giordano, Mario


    Roč. 478, č. 4 (2016), s. 1555-1562 ISSN 0006-291X Institutional support: RVO:61388971 Keywords : ATP sulfurylase * cysteine * Sulfur metabolism Subject RIV: EE - Microbiology, Virology Impact factor: 2.466, year: 2016

  13. The Role of ATP in Sleep Regulation

    Directory of Open Access Journals (Sweden)

    Sachiko eChikahisa


    Full Text Available One of the functions of sleep is to maintain energy balance in the brain. There are a variety of hypotheses related to how metabolic pathways interact with sleep/wake regulation. A major finding that demonstrates an interaction between sleep and metabolic homeostasis is the involvement of adenosine in sleep homeostasis. An accumulation of adenosine is supplied from ATP, which can act as an energy currency in the cell. Extracellularly, ATP can act as an activity-dependent signaling molecule, especially in regard to communication between neurons and glia, including astrocytes. Furthermore, the intracellular AMP/ATP ratio controls the activity of AMP-activated protein kinase (AMPK, which is a potent energy regulator and is recently reported to play a role in the regulation of sleep homeostasis. Brain ATP may support multiple functions in the regulation of the sleep/wake cycle and sleep homeostasis.

  14. NCEP ATP III dan Framingham score


    Hasan, Refli; Fahila, Reny


    Laporan ini merupakan Program Pendidikan Kolesterol National yang diperbaharui yaitu pedoman klinis untuk melakukan pengujian kolesterol dan manajemen. ATP III dibuat berdasarkan bukti dan laporan ekstensif yang akan menjadi referensi dan rekomendasi ilmiah. Laporan ATP III dapat dijadikan pedoman untuk pemberian terapi penurun kolesterol yang intensif dalam praktek. Pedoman ini hanya sebagai informasi , tidak dapat mempengaruhi secara mutlak dalam penilaian klinis dokter yang akhirnya menent...

  15. Regulation of DNA synthesis and the cell cycle in human prostate cancer cells and lymphocytes by ovine uterine serpin

    Directory of Open Access Journals (Sweden)

    Hansen Peter J


    Full Text Available Abstract Background Uterine serpins are members of the serine proteinase inhibitor superfamily. Like some other serpins, these proteins do not appear to be functional proteinase inhibitors. The most studied member of the group, ovine uterine serpin (OvUS, inhibits proliferation of several cell types including activated lymphocytes, bovine preimplantation embryos, and cell lines for lymphoma, canine primary osteosarcoma and human prostate cancer (PC-3 cells. The goal for the present study was to evaluate the mechanism by which OvUS inhibits cell proliferation. In particular, it was tested whether inhibition of DNA synthesis in PC-3 cells involves cytotoxic actions of OvUS or the induction of apoptosis. The effect of OvUS in the production of the autocrine and angiogenic cytokine interleukin (IL-8 by PC-3 cells was also determined. Finally, it was tested whether OvUS blocks specific steps in the cell cycle using both PC-3 cells and lymphocytes. Results Recombinant OvUS blocked proliferation of PC-3 cells at concentrations as low as 8 μg/ml as determined by measurements of [3H]thymidine incorporation or ATP content per well. Treatment of PC-3 cells with OvUS did not cause cytotoxicity or apoptosis or alter interleukin-8 secretion into medium. Results from flow cytometry experiments showed that OvUS blocked the entry of PC-3 cells into S phase and the exit from G2/M phase. In addition, OvUS blocked entry of lymphocytes into S phase following activation of proliferation with phytohemagglutinin. Conclusion Results indicate that OvUS acts to block cell proliferation through disruption of the cell cycle dynamics rather than induction of cytotoxicity or apoptosis. The finding that OvUS can regulate cell proliferation makes this one of only a few serpins that function to inhibit cell growth.

  16. Genetické a funkční příčiny mitochondriálních chorob vyvolaných defekty ATP syntázy


    Tauchmannová, Kateřina


    Disorders of ATP synthase, the key enzyme of mitochondrial energy provision belong to the most severe metabolic diseases presenting mostly as early-onset mitochondrial encephalo-cardio-myopathies. Mutations in four nuclear genes can result in isolated deficiency of ATP synthase, all sharing a similar biochemical phenotype - pronounced decrease in the content of fully assembled and functional ATP synthase complex. The thesis summarises studies on two distinct causes of ATP synthase deficiency....

  17. The Role of ATP in the Regulation of NCAM Function

    DEFF Research Database (Denmark)

    Hübschmann, Martin; Skladchikova, Galina


    overlaps with the site of NCAM-FGFR interaction, and ATP is capable of disrupting NCAM-FGFR binding. This implies that NCAM signaling through FGFR can be regulated by ATP, which is supported by the observation that ATP can abrogate NCAM-induced neurite outgrowth. Finally, ATP can induce NCAM ectodomain...... shedding, possibly affecting the structural plasticity associated with learning and memory....

  18. Curcumin and Cholecalciferol in Treating Patients With Previously Untreated Stage 0-II Chronic Lymphocytic Leukemia or Small Lymphocytic Lymphoma (United States)


    Contiguous Stage II Small Lymphocytic Lymphoma; Noncontiguous Stage II Small Lymphocytic Lymphoma; Stage 0 Chronic Lymphocytic Leukemia; Stage I Chronic Lymphocytic Leukemia; Stage I Small Lymphocytic Lymphoma; Stage II Chronic Lymphocytic Leukemia

  19. Duchenne muscular dystrophy: normal ATP turnover in cultured cells

    International Nuclear Information System (INIS)

    Fox, I.H.; Bertorini, T.; Palmieri, G.M.A.; Shefner, R.


    This paper examines ATP metabolism in cultured muscle cells and fibroblasts from patients with Duchenne dystrophy. ATP and ADP levels were the same in cultured cells from normal subjects and patients and there was no difference in ATP synthesis or degradation. The ATP synthesis was measured by the incorporation of C 14-U-adenine into aTP and ADP. although there was a significant decrease in radioactively labelled ATP after incubation with deoxyglucose in Duchenne muscle cells, there was no difference in ATP concentration of ADP metabolism

  20. Blockade of Extracellular ATP Effect by Oxidized ATP Effectively Mitigated Induced Mouse Experimental Autoimmune Uveitis (EAU.

    Directory of Open Access Journals (Sweden)

    Ronglan Zhao

    Full Text Available Various pathological conditions are accompanied by ATP release from the intracellular to the extracellular compartment. Extracellular ATP (eATP functions as a signaling molecule by activating purinergic P2 purine receptors. The key P2 receptor involved in inflammation was identified as P2X7R. Recent studies have shown that P2X7R signaling is required to trigger the Th1/Th17 immune response, and oxidized ATP (oxATP effectively blocks P2X7R activation. In this study we investigated the effect of oxATP on mouse experimental autoimmune uveitis (EAU. Our results demonstrated that induced EAU in B6 mice was almost completely abolished by the administration of small doses of oxATP, and the Th17 response, but not the Th1 response, was significantly weakened in the treated mice. Mechanistic studies showed that the therapeutic effects involve the functional change of a number of immune cells, including dendritic cells (DCs, T cells, and regulatory T cells. OxATP not only directly inhibits the T cell response; it also suppresses T cell activation by altering the function of DCs and Foxp3+ T cell. Our results demonstrated that inhibition of P2X7R activation effectively exempts excessive autoimmune inflammation, which may indicate a possible therapeutic use in the treatment of autoimmune diseases.

  1. Extracellular ATP in the Exocrine Pancreas – ATP Release, Signalling and Metabolism

    DEFF Research Database (Denmark)

    Kowal, Justyna Magdalena

    release. So far, the contribution of duct cells in purinergic signalling has never been studied. This work presents that both acinar and duct cells are sources of extracellular ATP in the exocrine pancreas. Here we show that duct cells release ATP in response to several physiological......ATP plays an important role as an autocrine/paracrine signalling molecule, being released from a number of tissues, in response to physiological and pathophysiological stimuli. Released ATP induces Ca2+ - and/or cAMP - dependent cellular responses via activation of ubiquitously expressed P2X and P2......, particularly during Ca2+ stress conditions. In conclusion, these studies demonstrate a complex regulation of purinergic signalling in exocrine pancreas. A crucial role for duct cells in mediating extracellular nucleotides homeostasis, involving ATP release, subsequent hydrolysis and conversion via...

  2. Radiosensitivities of sensitized lymphocytes

    International Nuclear Information System (INIS)

    Taniguchi, Kazuto


    Immunization of mice with cell antigens such as allogeneic tumor cells or xenogeneic erythrocytes raises a variety of immune reactions mediated by T lymphocytes: i.e. delayed type hypersensitivity (DTH), cytotoxicity, and antibody production. The radiosensitivities of these reactions were examined in mice exposed to 600 R x-irradiation a few hours before or after immunization. 1) DTH to xenogeneic erythrocytes, as demonstrated by footpad reaction, was not suppressed by irradiation 3 h before or after immunization. DTH to allogeneic tumor cells, as demonstrated by a migration inhibition test, hardly developed in mice that had been irradiated before or after immunization. It may have belonged to distinct types of delayed reactions which were mediated by distinct subpopulations of T lymphocytes. 2) Cytotoxicity against allogeneic cells and xenogeneic erythrocytes showed almost the same radiosensitivity. It was scarcely detected in mice that had been irradiated before immunization. However, a low but definite degree of cytotoxicity was detected in mice that had been irradiated only a few hours after immunization. Solubilized allogeneic cells instead of native cells were used as immunizing antigens. It was also possible for precursor cells with cytotoxicity to acquire a radioresistant nature by immunization of solubilized antigens, but native cells were required as stimulation for radioresistant precursor cells to differentiated into nature cytotoxic effector cells. 3) Antibody production against xenogeneic erythrocytes or allogeneic cells was almost completely depleted in mice that had been irradiated before or after immunization. It is possible that antibody production essentially requires cell division and clonal expansion of B lymphocytes. (Bell, E.)

  3. Nuclear genetic defects of mitochondrial ATP synthase

    Czech Academy of Sciences Publication Activity Database

    Hejzlarová, Kateřina; Mráček, Tomáš; Vrbacký, Marek; Kaplanová, Vilma; Karbanová, Vendula; Nůsková, Hana; Pecina, Petr; Houštěk, Josef


    Roč. 63, Suppl.1 (2014), S57-S71 ISSN 0862-8408 R&D Projects: GA ČR(CZ) GAP303/11/0970; GA ČR GAP303/12/1363; GA MZd(CZ) NT12370; GA MZd(CZ) NT14050 Grant - others:Univerzita Karlova(CZ) 370411 Institutional support: RVO:67985823 Keywords : mitochondrial diseases * TMEM70 * ATPAF1 * ATP5A1 * ATP5E Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.293, year: 2014

  4. Relationship of tightly bound ADP and ATP to control and catalysis by chloroplast ATP synthase

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, J.; Xue, Z.; Du, Z.; Melese, T.; Boyer, P.D.


    Whether the tightly bound ADP that can cause a pronounced inhibition of ATP hydrolysis by the chloroplast ATP synthase and F/sub 1/ ATPase (CF/sub 1/) is bound at catalytic sites or at noncatalytic regulatory sites or both has been uncertain. The authors have used photolabeling by 2-azido-ATP and 2-azido-ADP to ascertain the location, with Mg/sup 2 +/ activation, of tightly bound ADP (a) that inhibits the hydrolysis of ATP by chloroplast ATP synthase, (b) that can result in an inhibited form of CF/sub 1/ that slowly regains activity during ATP hydrolysis, and (c) that arises when low concentrations of ADP markedly inhibit the hydrolysis of GTP by CF/sub 1/. The data show that in all instances the inhibition is associated with ADP binding without inorganic phosphate (P/sub i/) at catalytic sites. After photophosphorylation of ADP or 2-azido-ADP with (/sup 32/P)P/sub i/, similar amounts of the corresponding triphosphates are present on washed thylakoid membranes. Trials with appropriately labeled substrates show that a small portion of the tightly bound 2-azido-ATP gives rise to covalent labeling with an ATP moiety at noncatalytic sites but that most of the bound 2-azido-ATP gives rise to covalent labeling with an ATP moiety at noncatalytic sites but that most of the bound 2-azido-ATP gives rise to covalent labeling by an ADP moiety at a catalytic site. They also report the occurrence of a 1-2-min delay in the onset of the Mg/sup 2 +/-induced inhibition after addition of CF/sub 1/ to solutions containing Mg/sup 2 +/ and ATP, and that this delay is not associated with the filling of noncatalytic sites. A rapid burst of P/sub i/ formation is followed by a much lower, constant steady-state rate. The burst is not observed with GTP as a substrate or with Ca/sup 2 +/ as the activating cation.

  5. Bioluminometric assay of ATP in mouse brain

    Indian Academy of Sciences (India)

    Firefly luciferase bioluminescence (FLB) is a highly sensitive and specific method for the analysis of adenosine-5-triphosphate (ATP) in biological samples. Earlier attempts to modify the FLB test for enhanced sensitivity have been typically based on in vitro cell systems. This study reports an optimized FLB procedure for the ...

  6. Dynanics of populations of T- and B-lymphocytes in the irradiated body

    International Nuclear Information System (INIS)

    Yarilin, A.A.


    On the basis of literary data analysis the estimation of lymphocyte radiosensitivity with the account of dividing this cell type into numerous varieties is given. Estimation results have shown that during in vitro irradiation at 1000 P dose rate in the first day 80 percent of blood B-cells and about 30 percent of T cells are killed. By the fourth day lymphocyte killing approaches maximum: B cells vanish practically completely, and T cells make up 6-8% of the initial content. The lymphocyte reduction greatly depends on an injury character. T and B lymphocyte reduction dynamics is in principle analogous except for some difference in reduction periods

  7. Lymphocyte signaling: beyond knockouts. (United States)

    Saveliev, Alexander; Tybulewicz, Victor L J


    The analysis of lymphocyte signaling was greatly enhanced by the advent of gene targeting, which allows the selective inactivation of a single gene. Although this gene 'knockout' approach is often informative, in many cases, the phenotype resulting from gene ablation might not provide a complete picture of the function of the corresponding protein. If a protein has multiple functions within a single or several signaling pathways, or stabilizes other proteins in a complex, the phenotypic consequences of a gene knockout may manifest as a combination of several different perturbations. In these cases, gene targeting to 'knock in' subtle point mutations might provide more accurate insight into protein function. However, to be informative, such mutations must be carefully based on structural and biophysical data.

  8. MRI of lymphocytic hypophysitis

    International Nuclear Information System (INIS)

    Feng Feng; Li Mingli; Li Xiaozhen; Meng Chunling; Jin zhengyu


    Objective: To describe the MR findings in patients with lymphocytic hypophysitis (LyH), and to discuss MR diagnostic value and limit in this disease entity and its differentiation with pituitary adenoma. Methods: Five pathologically proven cases of LyH were recruited in this study. The main complaints of the patients were polydipsia, polyuria, and headache. The preoperative MR images and clinical manifestations were analyzed retrospectively. Results: MR findings of the 5 patients with LyH included enlargement of pituitary gland, stalk thickening, disappearance of high signal of neurohypophysis on T 1 WI, and marked Gadolinium enhancement of the lesions. Homogeneous enhancement was found in 2 cases, while heterogeneous enhancement was in 3 cases. Involvement of the cavernous sinus and dura mater on dorsum sella and clivus were found in 2 patients. Conclusion: The diagnosis of LyH should be suggested when the enlarged pituitary gland is associated with central diabetes insipidus, and with/without dysfunction of adenohypophysis. (authors)

  9. ATP-consuming and ATP-generating enzymes secreted by pancreas

    DEFF Research Database (Denmark)

    Yegutkin, Gennady G; Samburski, Sergei S; Jalkanen, Sirpa


    -generating enzymes in pancreatic juice, adenylate kinase, and NDP kinase, capable of sequentially phosphorylating AMP via ADP to ATP. Activities of nonspecific phosphatases, nucleotide pyrophosphatase/phosphodiesterases, and adenosine deaminase were negligible. Taken together, CCK-8 stimulation of pancreas causes...

  10. Co-Culturing of Multipotent Mesenchymal Stromal Cells with Autological and Allogenic Lymphocytes. (United States)

    Kapranov, N M; Davydova, Yu O; Gal'tseva, I V; Petinati, N A; Bakshinskaitė, M V; Drize, N I; Kuz'mina, L A; Parovichnikova, E N; Savchenko, V G


    We studied the effect of autologous and allogeneic lymphocytes on multipotent mesenchymal stromal cells in co-culture. It is shown that changes in multipotent mesenchymal stromal cells and in lymphocytes did not depend on the source of lymphocytes. Contact with lymphocytes triggers expression of HLA-DR molecules on multipotent mesenchymal stromal cells and these cells lose their immune privilege. In multipotent mesenchymal stromal cells, the relative level of expression of factors involved in immunomodulation (IDO1, PTGES, and IL-6) and expression of adhesion molecule ICAM1 increased, while expression of genes involved in the differentiation of multipotent mesenchymal stromal cells remained unchanged. Priming of multipotent mesenchymal stromal cells with IFN did not affect these changes. In turn, lymphocytes underwent activation, expression of HLA-DR increased, subpopulation composition of lymphocytes changed towards the increase in the content of naïve T cells. These findings are important for cell therapy.

  11. Functional expression of a heterologous nickel-dependent, ATP-independent urease in Saccharomyces cerevisiae. (United States)

    Milne, N; Luttik, M A H; Cueto Rojas, H F; Wahl, A; van Maris, A J A; Pronk, J T; Daran, J M


    In microbial processes for production of proteins, biomass and nitrogen-containing commodity chemicals, ATP requirements for nitrogen assimilation affect product yields on the energy producing substrate. In Saccharomyces cerevisiae, a current host for heterologous protein production and potential platform for production of nitrogen-containing chemicals, uptake and assimilation of ammonium requires 1 ATP per incorporated NH3. Urea assimilation by this yeast is more energy efficient but still requires 0.5 ATP per NH3 produced. To decrease ATP costs for nitrogen assimilation, the S. cerevisiae gene encoding ATP-dependent urease (DUR1,2) was replaced by a Schizosaccharomyces pombe gene encoding ATP-independent urease (ure2), along with its accessory genes ureD, ureF and ureG. Since S. pombe ure2 is a Ni(2+)-dependent enzyme and Saccharomyces cerevisiae does not express native Ni(2+)-dependent enzymes, the S. pombe high-affinity nickel-transporter gene (nic1) was also expressed. Expression of the S. pombe genes into dur1,2Δ S. cerevisiae yielded an in vitro ATP-independent urease activity of 0.44±0.01 µmol min(-1) mg protein(-1) and restored growth on urea as sole nitrogen source. Functional expression of the Nic1 transporter was essential for growth on urea at low Ni(2+) concentrations. The maximum specific growth rates of the engineered strain on urea and ammonium were lower than those of a DUR1,2 reference strain. In glucose-limited chemostat cultures with urea as nitrogen source, the engineered strain exhibited an increased release of ammonia and reduced nitrogen content of the biomass. Our results indicate a new strategy for improving yeast-based production of nitrogen-containing chemicals and demonstrate that Ni(2+)-dependent enzymes can be functionally expressed in S. cerevisiae. Copyright © 2015 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  12. A label-free electrochemiluminescent sensor for ATP detection based on ATP-dependent ligation. (United States)

    Zhao, Tingting; Lin, Chunshui; Yao, Qiuhong; Chen, Xi


    In this work, we describe a new label-free, sensitive and highly selective strategy for the electrochemiluminescent (ECL) detection of ATP at the picomolar level via ATP-induced ligation. The molecular-beacon like DNA probes (P12 complex) are self-assembled on a gold electrode. The presence of ATP leads to the ligation of P12 complex which blocks the digestion by Exonuclease III (Exo III). The protected P12 complex causes the intercalation of numerous ECL indicators (Ru(phen)3(2+)) into the duplex DNA grooves, resulting in significantly amplified ECL signal output. Since the ligating site of T4 DNA ligase and the nicking site of Exo III are the same, it involves no long time of incubation for conformation change. The proposed strategy combines the amplification power of enzyme and the inherent high sensitivity of the ECL technique and enables picomolar detection of ATP. The developed strategy also shows high selectivity against ATP analogs, which makes our new label-free and highly sensitive ligation-based method a useful addition to the amplified ATP detection arena. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Genotoxic damage in cultured human peripheral blood lymphocytes ...

    African Journals Online (AJOL)

    Falaq Naz


    Jun 29, 2012 ... Genotoxic damage in cultured human peripheral blood lymphocytes of oral ... catechol estrogens and quinines, via redox reactions causes oxidative damage to .... volume was prepared for each donor. About, 0.8 ml of cell sus .... duce the adverse effects of OCs, such as the reduction in the estrogen content.

  14. Carbon and energy metabolism of atp mutants of Escherichia coli

    DEFF Research Database (Denmark)

    Jensen, Peter Ruhdal; Michelsen, Ole


    strain is not able to utilize the resulting proton motive force for ATP synthesis. Indeed, the ratio of ATP concentration to ADP concentration was decreased from 19 in the wild type to 7 in the atp mutant, and the membrane potential of the atp deletion strain was increased by 20%, confirming......The membrane-bound H+-ATPase plays a key role in free-energy transduction of biological systems. We report how the carbon and energy metabolism of Escherichia coli changes in response to deletion of the atp operon that encodes this enzyme. Compared with the isogenic wild-type strain, the growth...... rate and growth yield were decreased less than expected for a shift from oxidative phosphorylation to glycolysis alone as a source of ATP. Moreover, the respiration rate of a atp deletion strain was increased by 40% compared with the wild-type strain. This result is surprising, since the atp deletion...

  15. Radiosensitivity of lymphocytes in vitro

    International Nuclear Information System (INIS)

    Albrecht, S.


    The radiation-induced impairment of human T-lymphocytes was studied after in vitro exposure to 25.8 - 825.6 mC/kg (100 - 3200 R) of 60 Co γ-radiation by ascertaining the change in lymphocyte response to phytohaemagglutin stimulation. Following methods were used: (1) measurement of 3 H-thymidine uptake, (2) E-rosette test, and (3) morphological examination of transformed T-cells. The results revealed a dose-dependent decline in T-cell number which was still somewhat more marked with lymphocytes purified over Ficoll-Isopaque prior to irradiation. (author)

  16. Laboratorial diagnosis of lymphocytic meningitis

    Directory of Open Access Journals (Sweden)

    Sérgio Monteiro de Almeida

    Full Text Available Meningitis is the main infectious central nervous system (CNS syndrome. Viruses or bacteria can cause acute meningitis of infectious etiology. The term "Aseptic Meningitis" denotes a clinical syndrome with a predominance of lymphocytes in the cerebrospinal fluid (CSF, with no common bacterial agents identified in the CSF. Viral meningitis is considered the main cause of lymphocyte meningitis. There are other etiologies of an infectious nature. CSF examination is essential to establish the diagnosis and to identify the etiological agent of lymphocytic meningitis. We examined CSF characteristics and the differential diagnosis of the main types of meningitis.

  17. Highly Divergent Mitochondrial ATP Synthase Complexes in Tetrahymena thermophila

    NARCIS (Netherlands)

    Nina, Praveen Balabaskaran; Dudkina, Natalya V.; Kane, Lesley A.; van Eyk, Jennifer E.; Boekema, Egbert J.; Mather, Michael W.; Vaidya, Akhil B.; Eisen, Jonathan A.

    The F-type ATP synthase complex is a rotary nano-motor driven by proton motive force to synthesize ATP. Its F(1) sector catalyzes ATP synthesis, whereas the F(o) sector conducts the protons and provides a stator for the rotary action of the complex. Components of both F(1) and F(o) sectors are

  18. ATP-dependent human RISC assembly pathways. (United States)

    Yoda, Mayuko; Kawamata, Tomoko; Paroo, Zain; Ye, Xuecheng; Iwasaki, Shintaro; Liu, Qinghua; Tomari, Yukihide


    The assembly of RNA-induced silencing complex (RISC) is a key process in small RNA-mediated gene silencing. In humans, small interfering RNAs (siRNAs) and microRNAs (miRNAs) are incorporated into RISCs containing the Argonaute (AGO) subfamily proteins Ago1-4. Previous studies have proposed that, unlike Drosophila melanogaster RISC assembly pathways, human RISC assembly is coupled with dicing and is independent of ATP. Here we show by careful reexamination that, in humans, RISC assembly and dicing are uncoupled, and ATP greatly facilitates RISC loading of small-RNA duplexes. Moreover, all four human AGO proteins show remarkably similar structural preferences for small-RNA duplexes: central mismatches promote RISC loading, and seed or 3'-mid (guide position 12-15) mismatches facilitate unwinding. All these features of human AGO proteins are highly reminiscent of fly Ago1 but not fly Ago2.

  19. ATP Maintenance via Two Types of ATP Regulators Mitigates Pathological Phenotypes in Mouse Models of Parkinson's Disease

    Directory of Open Access Journals (Sweden)

    Masaki Nakano


    Full Text Available Parkinson's disease is assumed to be caused by mitochondrial dysfunction in the affected dopaminergic neurons in the brain. We have recently created small chemicals, KUSs (Kyoto University Substances, which can reduce cellular ATP consumption. By contrast, agonistic ligands of ERRs (estrogen receptor-related receptors are expected to raise cellular ATP levels via enhancing ATP production. Here, we show that esculetin functions as an ERR agonist, and its addition to culture media enhances glycolysis and mitochondrial respiration, leading to elevated cellular ATP levels. Subsequently, we show the neuroprotective efficacies of KUSs, esculetin, and GSK4716 (an ERRγ agonist against cell death in Parkinson's disease models. In the surviving neurons, ATP levels and expression levels of α-synuclein and CHOP (an ER stress-mediated cell death executor were all rectified. We propose that maintenance of ATP levels, by inhibiting ATP consumption or enhancing ATP production, or both, would be a promising therapeutic strategy for Parkinson's disease.

  20. Stages of Chronic Lymphocytic Leukemia (United States)

    ... of the lymph system . Having relatives who are Russian Jews or Eastern European Jews. Signs and symptoms ... information about clinical trials is also available. To Learn More About Chronic Lymphocytic Leukemia For more information ...

  1. H+/ATP ratio during ATP hydrolysis by mitochondria: modification of the chemiosmotic theory. (United States)

    Brand, M D; Lehninger, A L


    The stoichiometry of H+ ejection by mitochondria during hydrolysis of a small pulse of ATP (the H+/ATP ratio) has been reexamined in the light of our recent observation that the stoichiometry of H+ ejection during mitochondrial electron transport (the H+/site ratio) was previously underestimated. We show that earlier estimates of the H+/ATP ratio in intact mitochondria were based upon an invalid correction for scaler H+ production and describe a modified method for determination of this ratio which utilizes mersalyl or N-ethylmaleimide to prevent complicating transmembrane movements of phosphate and H+. This method gives a value for the H+/ATP ratio of 2.0 without the need for questionable corrections, compared with a value of 3.0 for the H+/site ratio also obtained by pulse methods. A modified version of the chemiosmotic theory is presented, in which 3 H+ are ejected per pair of electrons traversing each energy-conserving site of the respiratory chain. Of these, 2 H+ return to the matrix through the ATPase to form ATP from ADP and phosphate, and 1 H+ returns through the combined action of the phosphate and adenine nucleotide exchange carriers of the inner membrane to allow the energy-requiring influx of Pi and ADP3- and efflux of ATP4-. Thus, up to one-third of the energy input into synthesis of extramitochondrial ATP may be required for transport work. Since other methods suggest that the H+/site significantly exceeds 3.0, an alternative possibility is that 4 h+ are ejected per site, followed by return of 3 H+ through the ATPase and 1 H+ through the operation of the proton-coupled membrane transport systems. PMID:17116

  2. A rapid method for the determination of microbial susceptibility using the firefly luciferase assay for adenosine triphosphate (ATP) (United States)

    Vellend, H.; Tuttle, S. A.; Barza, M.; Weinstein, L.; Picciolo, G. L.; Chappelle, E. W.


    Luciferase assay for adenosine triphosphate (ATP) was optimized for pure bacteria in broth in order to evaluate if changes in bacterial ATP content could be used as a rapid measure of antibiotic effect on microorganisms. Broth cultures of log phase bacteria were incubated at 310 K (37 C) for 2.5 hours at antimicrobial concentrations which resulted in the best discrimination between sensitive and resistant strains. Eighty-seven strains of 11 bacterial species were studied for their susceptibility to 12 commonly used antimicrobial agents: ampicillin, Penicillin G, nafcillin, carbenicillin, cephalothin, tetracycline, erythromycin, clindamycin, gentamicin, nitrofurantoin, colistin, and chloramplenicol. The major advantage of the ATP system over existing methods of rapid microbial susceptibility testing is that the assay can be made specific for bacterial ATP.

  3. The ATP/DNA Ratio Is a Better Indicator of Islet Cell Viability Than the ADP/ATP Ratio (United States)

    Suszynski, T.M.; Wildey, G.M.; Falde, E.J.; Cline, G.W.; Maynard, K. Stewart; Ko, N.; Sotiris, J.; Naji, A.; Hering, B.J.; Papas, K.K.


    Real-time, accurate assessment of islet viability is critical for avoiding transplantation of nontherapeutic preparations. Measurements of the intracellular ADP/ATP ratio have been recently proposed as useful prospective estimates of islet cell viability and potency. However, dead cells may be rapidly depleted of both ATP and ADP, which would render the ratio incapable of accounting for dead cells. Since the DNA of dead cells is expected to remain stable over prolonged periods of time (days), we hypothesized that use of the ATP/DNA ratio would take into account dead cells and may be a better indicator of islet cell viability than the ADP/ATP ratio. We tested this hypothesis using mixtures of healthy and lethally heat-treated (HT) rat insulinoma cells and human islets. Measurements of ATP/DNA and ADP/ATP from the known mixtures of healthy and HT cells and islets were used to evaluate how well these parameters correlated with viability. The results indicated that ATP and ADP were rapidly (within 1 hour) depleted in HT cells. The fraction of HT cells in a mixture correlated linearly with the ATP/DNA ratio, whereas the ADP/ADP ratio was highly scattered, remaining effectively unchanged. Despite similar limitations in both ADP/ADP and ATP/DNA ratios, in that ATP levels may fluctuate significantly and reversibly with metabolic stress, the results indicated that ATP/DNA was a better measure of islet viability than the ADP/ATP ratio. PMID:18374063

  4. Lymphocytes accelerate epithelial tight junction assembly: role of AMP-activated protein kinase (AMPK.

    Directory of Open Access Journals (Sweden)

    Xiao Xiao Tang


    Full Text Available The tight junctions (TJs, characteristically located at the apicolateral borders of adjacent epithelial cells, are required for the proper formation of epithelial cell polarity as well as for sustaining the mucosal barrier to the external environment. The observation that lymphocytes are recruited by epithelial cells to the sites of infection [1] suggests that they may play a role in the modulation of epithelial barrier function and thus contribute to host defense. To test the ability of lymphocytes to modulate tight junction assembly in epithelial cells, we set up a lymphocyte-epithelial cell co-culture system, in which Madin-Darby canine kidney (MDCK cells, a well-established model cell line for studying epithelial TJ assembly [2], were co-cultured with mouse lymphocytes to mimic an infection state. In a typical calcium switch experiment, the TJ assembly in co-culture was found to be accelerated compared to that in MDCK cells alone. This accelaration was found to be mediated by AMP-activated protein kinase (AMPK. AMPK activation was independent of changes in cellular ATP levels but it was found to be activated by the pro-inflammatory cytokine TNF-alpha. Forced suppression of AMPK, either with a chemical inhibitor or by knockdown, abrogated the accelerating effect of lymphocytes on TJ formation. Similar results were also observed in a co-culture with lymphocytes and Calu-3 human airway epithelial cells, suggesting that the activation of AMPK may be a general mechanism underlying lymphocyte-accelerated TJ assembly in different epithelia. These results suggest that signals from lymphocytes, such as cytokines, facilitate TJ assembly in epithelial cells via the activation of AMPK.

  5. Radioprotective effect of antioxidants on human blood lymphocytes

    International Nuclear Information System (INIS)

    Wang Mingsuo; Gu Xuandi; Zhu Genbo; Feng Jixing; Su Liaoyuan


    By using an improved fluorometric method with 2-thiobarbituric acid (TBA) as fluorometric agent, the antiradiation effects of four kinds of antioxidants on 60 Co γ-ray irradiation inducing final products of lipid peroxides (LPO), i.e. malodialdehyde (MDA) content changes in human blood lymphocytes, were investigated with LPO value as an indicator. The results of the experiment were as following: (1)The radioprotective effect of exogenous antioxidants added to human blood lymphocytes on radiation-induced LPO damage of cellular membrane were remarkable; (2)The radioprotective beneficial sequences of four kinds of antioxidants were arranged like this: SOD > VE >VC, Se 4+ ; (3)Radioprotective effects of antioxidants on radiation-induced damage varied especially with the property of antioxidants, drug concentration, and pretreatment and monitoring time, etc., as well as irradiated dosage and various kinds of incubated cells. In addition, the mechanism of these antioxidants as radioprotectants on human blood lymphocytes is discussed in connection with LPO damage and radioprotection

  6. Lymphocyte Glucose and Glutamine Metabolism as Targets of the Anti-Inflammatory and Immunomodulatory Effects of Exercise

    Directory of Open Access Journals (Sweden)

    Frederick Wasinski


    Full Text Available Glucose and glutamine are important energetic and biosynthetic nutrients for T and B lymphocytes. These cells consume both nutrients at high rates in a function-dependent manner. In other words, the pathways that control lymphocyte function and survival directly control the glucose and glutamine metabolic pathways. Therefore, lymphocytes in different functional states reprogram their glucose and glutamine metabolism to balance their requirement for ATP and macromolecule production. The tight association between metabolism and function in these cells was suggested to introduce the possibility of several pathologies resulting from the inability of lymphocytes to meet their nutrient demands under a given condition. In fact, disruptions in lymphocyte metabolism and function have been observed in different inflammatory, metabolic, and autoimmune pathologies. Regular physical exercise and physical activity offer protection against several chronic pathologies, and this benefit has been associated with the anti-inflammatory and immunomodulatory effects of exercise/physical activity. Chronic exercise induces changes in lymphocyte functionality and substrate metabolism. In the present review, we discuss whether the beneficial effects of exercise on lymphocyte function in health and disease are associated with modulation of the glucose and glutamine metabolic pathways.

  7. Effect of tributyltin (TBT) on ATP levels in human natural killer (NK) cells: relationship to TBT-induced decreases in NK function. (United States)

    Dudimah, Fred D; Odman-Ghazi, Sabah O; Hatcher, Frank; Whalen, Margaret M


    The purpose of this study was to investigate the role that tributyltin (TBT)-induced decreases in ATP levels may play in TBT-induced decreases in the tumor lysing (lytic) function of natural killer (NK) cells. NK cells are a subset of lymphocytes that act as an initial immune defense against tumor cells and virally infected cells. TBT is an environmental contaminant that has been detected in human blood, which has been shown to interfere with ATP synthesis. Previous studies have shown that TBT is able to decrease very significantly the lytic function of NK cells. In this study NK cells were exposed to various concentrations of TBT and to two other compounds that interfere with ATP synthesis (rotenone a complex I inhibitor and oligomycin an ATP synthase inhibitor) for various lengths of time before determining the levels of ATP and lytic function. Exposures of NK cells to 10, 25, 50 and 100 nm TBT did not significantly reduce ATP levels after 24 h. However, these same exposures caused significant decreases in cytotoxic function. Studies of brief 1 h exposures to a range of TBT, rotenone and oligomycin concentrations followed by 24 h, 48 h and 6 day periods in compound-free media prior to assaying for ATP levels or cytotoxic function showed that each of the compounds caused persistent decreases in ATP levels and lytic function of NK cells. Exposures to 0.05-5 microm rotenone or oligomycin for 1 h reduced ATP levels by 20-25% but did not have any measurable effect on the ability of NK cells to lyse tumor cells. ATP levels were also decreased by about 20-25% after 24 h or 48 h exposures to rotenone or oligomycin (0.5 microm ), and the lytic function was decreased by about 50%. The results suggest that TBT-induced decreases in ATP levels were not responsible for the loss of cytotoxic function seen at 1 h and 24 h. However, TBT-induced decreases of NK-ATP levels may be at least in part responsible for losses of NK-cytotoxic function seen after 48 h and 6 day exposures

  8. Bioanalytical Applications of Real-Time ATP Imaging Via Bioluminescence

    Energy Technology Data Exchange (ETDEWEB)

    Gruenhagen, Jason Alan [Iowa State Univ., Ames, IA (United States)


    The research discussed within involves the development of novel applications of real-time imaging of adenosine 5'-triphosphate (ATP). ATP was detected via bioluminescence and the firefly luciferase-catalyzed reaction of ATP and luciferin. The use of a microscope and an imaging detector allowed for spatially resolved quantitation of ATP release. Employing this method, applications in both biological and chemical systems were developed. First, the mechanism by which the compound 48/80 induces release of ATP from human umbilical vein endothelial cells (HUVECs) was investigated. Numerous enzyme activators and inhibitors were utilized to probe the second messenger systems involved in release. Compound 48/80 activated a G{sub q}-type protein to initiate ATP release from HUVECs. Ca2+ imaging along with ATP imaging revealed that activation of phospholipase C and induction of intracellular Ca2+ signaling were necessary for release of ATP. Furthermore, activation of protein kinase C inhibited the activity of phospholipase C and thus decreased the magnitude of ATP release. This novel release mechanism was compared to the existing theories of extracellular release of ATP. Bioluminescence imaging was also employed to examine the role of ATP in the field of neuroscience. The central nervous system (CNS) was dissected from the freshwater snail Lymnaea stagnalis. Electrophysiological experiments demonstrated that the neurons of the Lymnaea were not damaged by any of the components of the imaging solution. ATP was continuously released by the ganglia of the CNS for over eight hours and varied from ganglion to ganglion and within individual ganglia. Addition of the neurotransmitters K+ and serotonin increased release of ATP in certain regions of the Lymnaea CNS. Finally, the ATP imaging technique was investigated for the study of drug release systems. MCM-41-type mesoporous nanospheres were loaded with ATP and end-capped with mercaptoethanol

  9. Electron transfer precedes ATP hydrolysis during nitrogenase catalysis (United States)

    Duval, Simon; Danyal, Karamatullah; Shaw, Sudipta; Lytle, Anna K.; Dean, Dennis R.; Hoffman, Brian M.; Antony, Edwin; Seefeldt, Lance C.


    The biological reduction of N2 to NH3 catalyzed by Mo-dependent nitrogenase requires at least eight rounds of a complex cycle of events associated with ATP-driven electron transfer (ET) from the Fe protein to the catalytic MoFe protein, with each ET coupled to the hydrolysis of two ATP molecules. Although steps within this cycle have been studied for decades, the nature of the coupling between ATP hydrolysis and ET, in particular the order of ET and ATP hydrolysis, has been elusive. Here, we have measured first-order rate constants for each key step in the reaction sequence, including direct measurement of the ATP hydrolysis rate constant: kATP = 70 s−1, 25 °C. Comparison of the rate constants establishes that the reaction sequence involves four sequential steps: (i) conformationally gated ET (kET = 140 s−1, 25 °C), (ii) ATP hydrolysis (kATP = 70 s−1, 25 °C), (iii) Phosphate release (kPi = 16 s−1, 25 °C), and (iv) Fe protein dissociation from the MoFe protein (kdiss = 6 s−1, 25 °C). These findings allow completion of the thermodynamic cycle undergone by the Fe protein, showing that the energy of ATP binding and protein–protein association drive ET, with subsequent ATP hydrolysis and Pi release causing dissociation of the complex between the Feox(ADP)2 protein and the reduced MoFe protein. PMID:24062462

  10. Electron transfer precedes ATP hydrolysis during nitrogenase catalysis. (United States)

    Duval, Simon; Danyal, Karamatullah; Shaw, Sudipta; Lytle, Anna K; Dean, Dennis R; Hoffman, Brian M; Antony, Edwin; Seefeldt, Lance C


    The biological reduction of N2 to NH3 catalyzed by Mo-dependent nitrogenase requires at least eight rounds of a complex cycle of events associated with ATP-driven electron transfer (ET) from the Fe protein to the catalytic MoFe protein, with each ET coupled to the hydrolysis of two ATP molecules. Although steps within this cycle have been studied for decades, the nature of the coupling between ATP hydrolysis and ET, in particular the order of ET and ATP hydrolysis, has been elusive. Here, we have measured first-order rate constants for each key step in the reaction sequence, including direct measurement of the ATP hydrolysis rate constant: kATP = 70 s(-1), 25 °C. Comparison of the rate constants establishes that the reaction sequence involves four sequential steps: (i) conformationally gated ET (kET = 140 s(-1), 25 °C), (ii) ATP hydrolysis (kATP = 70 s(-1), 25 °C), (iii) Phosphate release (kPi = 16 s(-1), 25 °C), and (iv) Fe protein dissociation from the MoFe protein (kdiss = 6 s(-1), 25 °C). These findings allow completion of the thermodynamic cycle undergone by the Fe protein, showing that the energy of ATP binding and protein-protein association drive ET, with subsequent ATP hydrolysis and Pi release causing dissociation of the complex between the Fe(ox)(ADP)2 protein and the reduced MoFe protein.

  11. A taste for ATP: neurotransmission in taste buds (United States)

    Kinnamon, Sue C.; Finger, Thomas E.


    Not only is ATP a ubiquitous source of energy but it is also used widely as an intercellular signal. For example, keratinocytes release ATP in response to numerous external stimuli including pressure, heat, and chemical insult. The released ATP activates purinergic receptors on nerve fibers to generate nociceptive signals. The importance of an ATP signal in epithelial-to-neuronal signaling is nowhere more evident than in the taste system. The receptor cells of taste buds release ATP in response to appropriate stimulation by tastants and the released ATP then activates P2X2 and P2X3 receptors on the taste nerves. Genetic ablation of the relevant P2X receptors leaves an animal without the ability to taste any primary taste quality. Of interest is that release of ATP by taste receptor cells occurs in a non-vesicular fashion, apparently via gated membrane channels. Further, in keeping with the crucial role of ATP as a neurotransmitter in this system, a subset of taste cells expresses a specific ectoATPase, NTPDase2, necessary to clear extracellular ATP which otherwise will desensitize the P2X receptors on the taste nerves. The unique utilization of ATP as a key neurotransmitter in the taste system may reflect the epithelial rather than neuronal origins of the receptor cells. PMID:24385952

  12. A taste for ATP: neurotransmission in taste buds

    Directory of Open Access Journals (Sweden)

    Thomas E. Finger


    Full Text Available Not only is ATP a ubiquitous source of energy but it is also used widely as an intercellular signal. For example, keratinocytes release ATP in response to numerous external stimuli including pressure, heat and chemical insult. The released ATP activates purinergic receptors on nerve fibers to generate nociceptive signals. The importance of an ATP signal in epithelial-to-neuronal signaling is nowhere more evident than in the taste system. The receptor cells of taste buds release ATP in response to appropriate stimulation by tastants and the released ATP then activates P2X2 and P2X3 receptors on the taste nerves. Genetic ablation of the relevant P2X receptors leaves an animal without the ability to taste any primary taste quality. Of interest is that release of ATP by taste receptor cells occurs in a non-vesicular fashion, apparently via gated membrane channels. Further, in keeping with the crucial role of ATP as a neurotransmitter in this system, a subset of taste cells expresses a specific ectoATPase, NTPDase2, necessary to clear extracellular ATP which otherwise will desensitize the P2X receptors on the taste nerves. The unique utilization of ATP as a key neurotransmitter in the taste system may reflect the epithelial rather than neuronal origins of the receptor cells.

  13. Etanercept overcomes P-glycoprotein-induced drug resistance in lymphocytes of patients with intractable rheumatoid arthritis. (United States)

    Tsujimura, Shizuyo; Saito, Kazuyoshi; Nakayamada, Shingo; Tanaka, Yoshiya


    P-glycoprotein (P-gp) on activated lymphocytes is an adenosine triphosphate (ATP)-binding cassette transporter that causes drug resistance by exclusion of intracellular drugs in patients with active rheumatoid arthritis (RA). However, infliximab with methotrexate (MTX) can overcome P-gp-mediated drug resistance. We encounter patients who cannot continue infliximab or MTX. Here we tested how etanercept affected P-gp-mediated drug resistance in such intractable RA patients. Peripheral lymphocytes of 11 RA patients (3 switched from infliximab and 8 who could not be treated with MTX) were analyzed for P-gp expression by flow cytometry and for drug exclusion using radioisotope-labeled dexamethasone. Activated lymphocytes of RA patients overexpressed P-gp and coexpressed CD69. Incubation of these lymphocytes with dexamethasone in vitro reduced intracellular dexamethasone levels. Two-week etanercept therapy significantly reduced P-gp expression and eliminated such P-gp- and CD69-high-expressing subgroup. The reduction in P-gp resulted in recovery of intracellular dexamethasone levels in lymphocytes and improvement of disease activity, thus allowing tapering of corticosteroids. None of the patients experienced any severe adverse effects. Etanercept is useful for overcoming P-gp-mediated treatment resistance in intractable RA patients who have to discontinue infliximab or are intolerant to MTX.

  14. [ATP-synthetase activity, respiration and cytochromes of rat heart mitochondria in aging and hyperthyroidism]. (United States)

    Lemeshko, V V; Kaliman, P A; Belostotskaia, L I; Uchitel', A A


    The ATP-synthetase activity, the rate of oxygen uptake under different metabolic conditions, the tightness of coupling of respiration to oxidative phosphorylation and the cytochrome contents in heart mitochondria of rats from different age groups were studied under normal conditions and in hyperthyroidism. It was found that heart mitochondria of aged animals did not practically differ in terms of their functional activity from those of the young animals. Administration of thyroxin to the animals from all age groups produced no significant effects on the state of mitochondria, increasing the rate of ATP synthesis on alpha-glycerophosphate, which was especially well-pronounced in aged animals, and the cytochrome content in 1-month-old rats.

  15. Impacts of high ATP supply from chloroplasts and mitochondria on the leaf metabolism of Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Chao eLiang


    Full Text Available Chloroplasts and mitochondria are the major ATP producing organelles in plant leaves. Arabidopsis thaliana purple acid phosphatase 2 (AtPAP2 is a phosphatase dually targeted to the outer membranes of both organelles and it plays a role in the import of selected nuclear-encoded proteins into these two organelles. Overexpression (OE of AtPAP2 in Arabidopsis thaliana accelerates plant growth and promotes flowering, seed yield and biomass at maturity. Measurement of ADP/ATP/NADP+/NADPH contents in the leaves of 20-day-old OE and wild-type lines at the end of night and at 1 and 8 h following illumination in a 16/8 h photoperiod revealed that the ATP levels and ATP/NADPH ratios were significantly increased in the OE line at all three time points. The AtPAP2 OE line is therefore a good model to investigate the impact of high energy on the global molecular status of Arabidopsis. In this study, transcriptome, proteome and metabolome profiles of the high ATP transgenic line were examined and compared with those of wild-type plants. A comparison of OE and WT at the end of the night provide valuable information on the impact of higher ATP output from mitochondria on plant physiology, as mitochondrial respiration is the major source of ATP in the dark in leaves. Similarly, comparison of OE and WT following illumination will provide information on the impact of higher energy output from chloroplasts on plant physiology. Overexpression of AtPAP2 was found to significantly affect the transcript and protein abundances of genes encoded by the two organellar genomes. For example, the protein abundances of many ribosomal proteins encoded by the chloroplast genome were higher in the AtPAP2 OE line under both light and dark conditions, while the protein abundances of multiple components of the photosynthetic complexes were lower. RNA-seq data also showed that the transcription of the mitochondrial genome is greatly affected by the availability of energy. These data

  16. Glucose is required to maintain high ATP-levels for the energy utilizing steps during PDT-induced apoptosis

    International Nuclear Information System (INIS)

    Oberdanner, C.; Plaetzer, K.; Kiesslich, T.; Krammer, B.


    Full text: Photodynamic therapy (PDT) may trigger apoptosis or necrosis in cancer cells. Several steps in the induction and execution of apoptosis require high amounts of adenosine-5'-triphosphate (ATP). Since the mitochondrial membrane potential (ΔΨ) decreases early in apoptosis, we raised the question about the mechanisms of maintaining a sufficiently high ATP-level. We therefore monitored ΔΨ and the intracellular ATP-level of apoptotic human epidermoid carcinoma cells (A431) after photodynamic treatment with aluminium (III) phthalocyanine tetrasulfonate chloride. A maximum of caspase-3 activation and nuclear fragmentation was found at fluences of about 4 -2 . Under these conditions apoptotic cells reduced ΔΨ rapidly, while the ATP-level remained high for 4 to 6 hours after treatment for cells supplied with glucose. To analyze the contribution of glycolysis to the energy supply during apoptosis experiments were carried out with cells deprivated of glucose. These cells showed a rapid drop of ATP-content and neither caspase-activation nor nuclear fragmentation could be detected. We conclude that the use of glucose as a source of ATP is obligatory for the execution of PDT-induced apoptosis. (author)

  17. Delayed contraction of the CD8+ T cell response toward lymphocytic choriomeningitis virus infection in mice lacking serglycin

    DEFF Research Database (Denmark)

    Grujic, Mirjana; Christensen, Jan P; Sørensen, Maria R


    (-/-)) mice with lymphocytic choriomeningitis virus (LCMV). Wt and SG(-/-) mice cleared 10(3) PFU of highly invasive LCMV with the same kinetics, and the CD8(+) T lymphocytes from wt and SG(-/-) animals did not differ in GrB, perforin, IFN-gamma, or TNF-alpha content. However, when a less invasive LCMV strain...

  18. ATP7B detoxifies silver in ciliated airway epithelial cells

    International Nuclear Information System (INIS)

    Ibricevic, Aida; Brody, Steven L.; Youngs, Wiley J.; Cannon, Carolyn L.


    Silver is a centuries-old antibiotic agent currently used to treat infected burns. The sensitivity of a wide range of drug-resistant microorganisms to silver killing suggests that it may be useful for treating refractory lung infections. Toward this goal, we previously developed a methylated caffeine silver acetate compound, SCC1, that exhibits broad-spectrum antimicrobial activity against clinical strains of bacteria in vitro and when nebulized to lungs in mouse infection models. Preclinical testing of high concentrations of SCC1 in primary culture mouse tracheal epithelial cells (mTEC) showed selective ciliated cell death. Ciliated cell death was induced by both silver- and copper-containing compounds but not by the methylated caffeine portion of SCC1. We hypothesized that copper transporting P-type ATPases, ATP7A and ATP7B, play a role in silver detoxification in the airway. In mTEC, ATP7A was expressed in non-ciliated cells, whereas ATP7B was expressed only in ciliated cells. The exposure of mTEC to SCC1 induced the trafficking of ATP7B, but not ATP7A, suggesting the presence of a cell-specific silver uptake and detoxification mechanisms. Indeed, the expression of the copper uptake protein CTR1 was also restricted to ciliated cells. A role of ATP7B in silver detoxification was further substantiated when treatment of SCC1 significantly increased cell death in ATP7B shRNA-treated HepG2 cells. In addition, mTEC from ATP7B -/- mice showed enhanced loss of ciliated cells compared to wild type. These studies are the first to demonstrate a cell type-specific expression of the Ag + /Cu + transporters ATP7A, ATP7B, and CTR1 in airway epithelial cells and a role for ATP7B in detoxification of these metals in the lung.

  19. [The lymphocyte transformation test in dermatology]. (United States)

    Zinn, K; Braun-Falco, O


    At first, immunologie and methodic basies of the lymphocyte transformation test are discussed. Then the results gained by this test in several dermatologic diseases are summarized. Finally, practice of the lymphocyte transformation test is critically reviewed.

  20. ATP release, generation and hydrolysis in exocrine pancreatic duct cells

    DEFF Research Database (Denmark)

    Kowal, Justyna Magdalena; Yegutkin, G.G.; Novak, Ivana


    Extracellular adenosine triphosphate (ATP) regulates pancreatic duct function via P2Y and P2X receptors. It is well known that ATP is released from upstream pancreatic acinar cells. The ATP homeostasis in pancreatic ducts, which secrete bicarbonate-rich fluid, has not yet been examined. First, ou...... may be important in pancreas physiology and potentially in pancreas pathophysiology....... aim was to reveal whether pancreatic duct cells release ATP locally and whether they enzymatically modify extracellular nucleotides/sides. Second, we wished to explore which physiological and pathophysiological factors may be important in these processes. Using a human pancreatic duct cell line, Capan...

  1. Application of luciferase assay for ATP to antimicrobial drug susceptibility (United States)

    Chappelle, E. W.; Picciolo, G. L.; Vellend, H.; Tuttle, S. A.; Barza, M. J.; Weinstein, L. (Inventor)


    The susceptibility of bacteria, particularly those derived from body fluids, to antimicrobial agents is determined in terms of an ATP index measured by culturing a bacterium in a growth medium. The amount of ATP is assayed in a sample of the cultured bacterium by measuring the amount of luminescent light emitted when the bacterial ATP is reacted with a luciferase-luciferin mixture. The sample of the cultured bacterium is subjected to an antibiotic agent. The amount of bacterial adenosine triphosphate is assayed after treatment with the antibiotic by measuring the luminescent light resulting from the reaction. The ATP index is determined from the values obtained from the assay procedures.

  2. Binding of ATP by pertussis toxin and isolated toxin subunits

    International Nuclear Information System (INIS)

    Hausman, S.Z.; Manclark, C.R.; Burns, D.L.


    The binding of ATP to pertussis toxin and its components, the A subunit and B oligomer, was investigated. Whereas, radiolabeled ATP bound to the B oligomer and pertussis toxin, no binding to the A subunit was observed. The binding of [ 3 H]ATP to pertussis toxin and the B oligomer was inhibited by nucleotides. The relative effectiveness of the nucleotides was shown to be ATP > GTP > CTP > TTP for pertussis toxin and ATP > GTP > TTP > CTP for the B oligomer. Phosphate ions inhibited the binding of [ 3 H]ATP to pertussis toxin in a competitive manner; however, the presence of phosphate ions was essential for binding of ATP to the B oligomer. The toxin substrate, NAD, did not affect the binding of [ 3 H]ATP to pertussis toxin, although the glycoprotein fetuin significantly decreased binding. These results suggest that the binding site for ATP is located on the B oligomer and is distinct from the enzymatically active site but may be located near the eukaryotic receptor binding site

  3. Binding of ATP by pertussis toxin and isolated toxin subunits

    Energy Technology Data Exchange (ETDEWEB)

    Hausman, S.Z.; Manclark, C.R.; Burns, D.L. (Center for Biologics Evaluation and Research, Bethesda, MD (USA))


    The binding of ATP to pertussis toxin and its components, the A subunit and B oligomer, was investigated. Whereas, radiolabeled ATP bound to the B oligomer and pertussis toxin, no binding to the A subunit was observed. The binding of ({sup 3}H)ATP to pertussis toxin and the B oligomer was inhibited by nucleotides. The relative effectiveness of the nucleotides was shown to be ATP > GTP > CTP > TTP for pertussis toxin and ATP > GTP > TTP > CTP for the B oligomer. Phosphate ions inhibited the binding of ({sup 3}H)ATP to pertussis toxin in a competitive manner; however, the presence of phosphate ions was essential for binding of ATP to the B oligomer. The toxin substrate, NAD, did not affect the binding of ({sup 3}H)ATP to pertussis toxin, although the glycoprotein fetuin significantly decreased binding. These results suggest that the binding site for ATP is located on the B oligomer and is distinct from the enzymatically active site but may be located near the eukaryotic receptor binding site.

  4. Lymphocyte receptors for pertussis toxin

    Energy Technology Data Exchange (ETDEWEB)

    Clark, C.G.; Armstrong, G.D. (Univ. of Alberta, Edmonton (Canada))


    We have investigated human T-lymphocyte receptors for pertussis toxin by affinity isolation and photoaffinity labeling procedures. T lymphocytes were obtained from peripheral human blood, surface iodinated, and solubilized in Triton X-100. The iodinated mixture was then passed through pertussis toxin-agarose, and the fractions were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Autoradiography of the fixed, dried gels revealed several bands in the pertussis toxin-bound fraction that were not observed in fractions obtained from histone or fetuin-agarose. Further investigations employed a photoaffinity labeling reagent, sulfosuccinimidyl 2-(p-azido-salicylamido)-1,3'-dithiopropionate, to identify pertussis toxin receptors in freshly isolated peripheral blood monocytic cells, T lymphocytes, and Jurkat cells. In all three cell systems, the pertussis toxin affinity probe specifically labeled a single protein species with an apparent molecular weight of 70,000 that was not observed when the procedure was performed in the presence of excess unmodified pertussis toxin. A protein comparable in molecular weight to the one detected by the photoaffinity labeling technique was also observed among the species that bound to pertussis toxin-agarose. The results suggest that pertussis toxin may bind to a 70,000-Da receptor in human T lymphocytes.

  5. A microculture technique for rat lymphocyte transformation. (United States)

    Lindsay, V J; Allardyce, R A


    We report the development of an economical microculture technique suitable for measuring rat lymphocyte response to mitogens and in mixed lymphocyte reactions. The effects of varying culture conditions, i.e. source of serum, addition and concentration of 2-mercaptoethanol, mitogen concentrations, culture incubation times, absorption of serum, lymphocyte numbers and microtitre plate well shape are described.

  6. Radiosensitivity of lymphocytes among Filipinos: final report

    International Nuclear Information System (INIS)

    Medina, F.I.S.; Gregorio, J.S.; Aguilar, C.P.; Poblete, E.E.


    This report is about the studies on the radiosensitivity of Filipino lymphocytes to radiation that can elucidate on the potential of blood chromosomes as biological dosimeters. The objective of this study is to determine the radiosensitivity of lymphocytes among Filipinos and to establish the radiation-induced chromosome anomaly standard curve in lymphocytes for radiological dosimetry. 47 refs., 9 figs., 1 tab

  7. Evidence for the Synthesis of ATP by an F0F1 ATP Synthase in Membrane Vesicles from Halorubrum Saccharovorum (United States)

    Faguy, David; Lawson, Darion; Hochstein, Lawrence I.; Chang, Sherwood (Technical Monitor)


    Vesicles prepared in a buffer containing ADP, Mg(2+) and Pi synthesized ATP at an initial rate of 2 nmols/min/mg protein after acidification of the bulk medium (pH 8 (right arrow) 4). The intravesicular ATP concentration reached a steady state after about 30 seconds and slowly declined thereafter. ATP synthesis was inhibited by low concentrations of dicyclohexylcarbodiimide and m-chlorophenylhydrazone indicating that synthesis took place in response to the proton gradient. NEM and PCMS, which inhibit vacuolar ATPases and the vacuolar-like ATPases of extreme halophiles, did not affect ATP synthesis, and, in fact, produced higher steady state levels of ATP. This suggested that two ATPase activities were present, one which catalyzed ATP synthesis and one that caused its hydrolysis. Azide, a specific inhibitor of F0F1 ATP Synthases, inhibited halobacterial ATP synthesis. The distribution of acridine orange as imposed by a delta pH demonstrated that azide inhibition was not due to the collapse of the proton gradient due to azide acting as a protonophore. Such an effect was observed, but only at azide concentrations higher than those that inhibited ATP synthesis. These results confirm the earler observations with cells of H. saccharovorum and other extreme halophiles that ATP synthesis is inconsistent with the operation of a vacuolar-like ATPase. Therefore, the observation that a vacuolar-like enzyme is responsible for ATP synthesis (and which serves as the basis for imputing ATP synthesis to the vacuolar-like ATPases of the extreme halophiles, and the Archaea in general) should be taken with some degree of caution.

  8. Historical review: ATP as a neurotransmitter. (United States)

    Burnstock, Geoffrey


    Purinergic signalling is now recognized to be involved in a wide range of activities of the nervous system, including neuroprotection, central control of autonomic functions, neural-glial interactions, control of vessel tone and angiogenesis, pain and mechanosensory transduction and the physiology of the special senses. In this article, I give a personal retrospective of the discovery of purinergic neurotransmission in the early 1970s, the struggle for its acceptance for approximately 20 years, the expansion into purinergic cotransmission and its eventual acceptance when receptor subtypes for ATP were cloned and characterized and when purinergic synaptic transmission between neurons in the brain and peripheral ganglia was described in the early 1990s. I also discuss the current status of the field, including recent interest in the pathophysiology of purinergic signalling and its therapeutic potential.

  9. Short-term effects of regional irradiation on lymphocytes, T lymphocytes and eosinophils

    International Nuclear Information System (INIS)

    Chazarin, C.; Roche, H.; Bugat, R.; Pris, F.


    Twenty-three cancer patients treated only by regional irradiation were studied. Radiotherapy was delivered to the pelvis in 14 patients and to the mediastinum in 9. T lymphocytes were evaluated with the Jondal technique. Before treatment, lymphocyte counts were identical in patients and control. Decreases in total lymphocytes and T lymphocytes became significant in both groups after 40 Gy. Significant rises in eosinophil counts were found only after abdominal irradiation and seemed unrelated to variations in lymphocyte counts [fr

  10. ATP storage and uptake by isolated pancreatic zymogen granules

    DEFF Research Database (Denmark)

    Haanes, Kristian Agmund; Novak, Ivana


    ATP is released from pancreatic acini in response to cholinergic and hormonal stimulation. The same stimuli cause exocytosis of ZG (zymogen granules) and release of digestive enzymes. The aim of the present study was to determine whether ZG stored ATP and to characterize the uptake mechanism for ...

  11. Renal epithelial cells can release ATP by vesicular fusion

    Directory of Open Access Journals (Sweden)

    Randi G Bjaelde


    Full Text Available Renal epithelial cells have the ability to release nucleotides as paracrine factors. In the intercalated cells of the collecting duct, ATP is released by connexin30 (cx30, which is selectively expressed in this cell type. However, ATP is released by virtually all renal epithelia and the aim of the present study was to identify possible alternative nucleotide release pathways in a renal epithelial cell model. We used MDCK (type1 cells to screen for various potential ATP release pathways. In these cells, inhibition of the vesicular H+-ATPases (bafilomycin reduced both the spontaneous and hypotonically (80%-induced nucleotide release. Interference with vesicular fusion using N-ethylamide markedly reduced the spontaneous nucleotide release, as did interference with trafficking from the endoplasmic reticulum to the Golgi apparatus (brefeldin A1 and vesicular transport (nocodazole. These findings were substantiated using a siRNA directed against SNAP-23, which significantly reduced spontaneous ATP release. Inhibition of pannexin and connexins did not affect the spontaneous ATP release in this cell type, which consists of ∼90% principal cells. TIRF-microscopy of either fluorescently-labeled ATP (MANT-ATP or quinacrine-loaded vesicles, revealed that spontaneous release of single vesicles could be promoted by either hypoosmolality (50% or ionomycin. This vesicular release decreased the overall cellular fluorescence by 5.8% and 7.6% respectively. In summary, this study supports the notion that spontaneous and induced ATP release can occur via exocytosis in renal epithelial cells.

  12. ATP synthase--a marvellous rotary engine of the cell. (United States)

    Yoshida, M; Muneyuki, E; Hisabori, T


    ATP synthase can be thought of as a complex of two motors--the ATP-driven F1 motor and the proton-driven Fo motor--that rotate in opposite directions. The mechanisms by which rotation and catalysis are coupled in the working enzyme are now being unravelled on a molecular scale.


    Forman, James; Möller, Göran


    Generation of cytotoxic effector cells by a unidirectional mixed lymphocyte reaction (MLR) in the mouse H-2 system was studied using labeled YAC (H-2a) leukemia cells as targets. The responding effector cell displayed a specific cytotoxic effect against target cells of the same H-2 genotype as the stimulating cell population. Killing of syngeneic H-2 cells was not observed, even when the labeled target cells were "innocent bystanders" in cultures where specific target cells were reintroduced. Similar results were found with spleen cells taken from mice sensitized in vivo 7 days earlier. The effector cell was not an adherent cell and was not activated by supernatants from MLR. The supernatants were not cytotoxic by themselves. When concanavalin A or phytohemagglutinin was added to the cytotoxic test system, target and effector cells were agglutinated. Under these conditions, killing of H-2a target cells was observed in mixed cultures where H-2a lymphocytes were also the effector cells. These findings indicate that specifically activated, probably thymus-derived lymphocytes, can kill nonspecifically once they have been activated and providing there is close contact between effector and target cells. Thus, specificity of T cell killing appears to be restricted to recognition and subsequent binding to the targets, the actual effector phase being nonspecific. PMID:4269560

  14. ATP economy of force maintenance in human tibialis anterior muscle

    DEFF Research Database (Denmark)

    Nakagawa, Yoshinao; Ratkevicius, Aivaras; Mizuno, Masao


    PURPOSE: The aim of this study was investigate ATP economy of force maintenance in the human tibialis anterior muscle during 60 s of anaerobic voluntary contraction at 50% of maximum voluntary contraction (MVC). METHODS: ATP turnover rate was evaluated using P magnetic resonance spectroscopy (P...... contraction. It averaged at 4.81 +/- 0.42 N.s.micromol-1, and correlated with the relative cross-sectional area of the muscle occupied by Type I fiber (r = 0.73, P contraction, subjects dropping in force showed lower ATP economy compared with those maintaining the force (3.......7 +/- 0.6 vs 5.3 +/- 0.6 N.s.micromol-1; P contraction could be due to an increase in the ATP economy of contracting muscle fibers offsetting the effects of increased temperature and low ATP economy...

  15. Keragaman Genetik Sekuen Gen ATP Synthase FO Subunit 6 (ATP6 Monyet Hantu (Tarsius Indonesia (GENETIC DIVERSITY STUDY OF ATP6 GENE SEQUENCES OF TARSIERS FROM INDONESIA

    Directory of Open Access Journals (Sweden)

    Rini Widayanti


    Full Text Available In a conservation effort, the identification of Tarsier species, on the bases of the morphological andmolecular characteristic is necessary. Up to now, the identification of the animals were based on themorphology and vocalizations, which is extremely difficult to identify each, tarsier species. The objective ofthis research was to study the genetic diversity on ATP6 gene of Tarsius sp. Based on sequencing of PCRproduct using primer ATP6F and ATP6R with 681 nts. PCR product. The sequence of ATP6 fragmentswere aligned with other primates from Gene bank with aid of software Clustal W, and were analyzed usingMEGA program version 4.0. Three different nucleotide sites were found (nucleotide no. 288, 321 and 367.The genetic distance based on nucleotide ATP6 sequence calculated using Kimura 2-parameter modelindicated that the smallest genetic distance 0%, biggest 0.8% and average 0, 2%. The phylogenetic treeusing neighbor joining method based on the sequence of nucleotide ATP6 gene could not be used todifferentiate among T. Dianae (from Central Sulawesi, T. Spectrum (from North Sulawesi, T. bancanus(from lampung, South Sumatera and T.bancanus from West Kalimantan.

  16. The mitochondrial phosphate transporters modulate plant responses to salt stress via affecting ATP and gibberellin metabolism in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Wei Zhu

    Full Text Available The mitochondrial phosphate transporter (MPT plays crucial roles in ATP production in plant cells. Three MPT genes have been identified in Arabidopsis thaliana. Here we report that the mRNA accumulations of AtMPTs were up-regulated by high salinity stress in A. thaliana seedlings. And the transgenic lines overexpressing AtMPTs displayed increased sensitivity to salt stress compared with the wild-type plants during seed germination and seedling establishment stages. ATP content and energy charge was higher in overexpressing plants than those in wild-type A. thaliana under salt stress. Accordingly, the salt-sensitive phenotype of overexpressing plants was recovered after the exogenous application of atractyloside due to the change of ATP content. Interestingly, Genevestigator survey and qRT-PCR analysis indicated a large number of genes, including those related to gibberellin synthesis could be regulated by the energy availability change under stress conditions in A. thaliana. Moreover, the exogenous application of uniconazole to overexpressing lines showed that gibberellin homeostasis was disturbed in the overexpressors. Our studies reveal a possible link between the ATP content mediated by AtMPTs and gibberellin metabolism in responses to high salinity stress in A. thaliana.

  17. ATP Maintenance via Two Types of ATP Regulators Mitigates Pathological Phenotypes in Mouse Models of Parkinson's Disease. (United States)

    Nakano, Masaki; Imamura, Hiromi; Sasaoka, Norio; Yamamoto, Masamichi; Uemura, Norihito; Shudo, Toshiyuki; Fuchigami, Tomohiro; Takahashi, Ryosuke; Kakizuka, Akira


    Parkinson's disease is assumed to be caused by mitochondrial dysfunction in the affected dopaminergic neurons in the brain. We have recently created small chemicals, KUSs (Kyoto University Substances), which can reduce cellular ATP consumption. By contrast, agonistic ligands of ERRs (estrogen receptor-related receptors) are expected to raise cellular ATP levels via enhancing ATP production. Here, we show that esculetin functions as an ERR agonist, and its addition to culture media enhances glycolysis and mitochondrial respiration, leading to elevated cellular ATP levels. Subsequently, we show the neuroprotective efficacies of KUSs, esculetin, and GSK4716 (an ERRγ agonist) against cell death in Parkinson's disease models. In the surviving neurons, ATP levels and expression levels of α-synuclein and CHOP (an ER stress-mediated cell death executor) were all rectified. We propose that maintenance of ATP levels, by inhibiting ATP consumption or enhancing ATP production, or both, would be a promising therapeutic strategy for Parkinson's disease. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  18. N114S mutation causes loss of ATP-induced aggregation of human phosphoribosylpyrophosphate synthetase 1

    International Nuclear Information System (INIS)

    Liu Honglin; Peng, Xiaohui; Zhao Fang; Zhang Guobin; Tao Ye; Luo Zhaofeng; Li Yang; Teng Maikun; Li Xu; Wei Shiqiang


    This study examined recombinant wild-type human phosphoribosylpyrophosphate synthetase 1 (wt-PRS1, EC and the point mutant Asn114Ser PRS1 (N114S-Mutant) in cells of a patient with primary gout. Dynamic light-scattering and sedimentation velocity experiments indicated that the monomeric wt-PRS1 in solution was assembled into hexamers after adding the substrate ATP. However, this ATP-induced aggregation effect was not observed with N114S-Mutant, which has a 50% higher enzymatic activity than that of wt-PRS1. Synchrotron radiation circular dichroism spectroscopy revealed that the point mutation causes an increase of α-helix content and a decrease of turn content. Examination of the crystal structure of wt-PRS1 indicated that 12 hydrogen bonds formed by 6 pairs of N114 and D139 have an important role in stabilizing the hexamer. We suggest that the substitution of S114 for N114 in N114S-Mutant leads to the rupture of 12 hydrogen bonds and breakage of the PO 4 3- allosteric site where PO 4 3- functions as a fixer of the ATP-binding loop. Therefore, we consider that formation of the hexamer as the structural basis of the ADP allosteric inhibition is greatly weakened by the N114S mutation, and that alteration of the ATP-binding loop conformation is the key factor in the increased activity of N114S-Mutant. These two factors could be responsible for the high level of activity of N114S-Mutant in this patient.

  19. ATP induced vasodilatation and purinergic receptors in the human leg: roles of nitric oxide, prostaglandins and adenosine

    DEFF Research Database (Denmark)

    Mortensen, Stefan P; Gonzalez-Alonso, Jose; Bune, Laurids


    .05) and was associated with a parallel lowering in leg vascular conductance and cardiac output and a compensatory increase in leg O2 extraction. Infusion of theophylline did not alter the ATP induced leg hyperemia or systemic variables. Real time PCR analysis of the mRNA content from the vastus lateralus muscle of 8...... subjects showed the highest expression of P2Y2 receptors of the 10 investigated P2 receptor subtypes. Immunohistochemistry showed that P2Y2 receptors were located in the endothelium of microvessels and smooth muscle cells, whereas P2X1 receptors were located in the endothelium and the sacrolemma....... Collectively, these results indicate that NO and prostaglandins, but not adenosine, play a role in ATP induced vasodilation in human skeletal muscle. The localization of the P2Y2 and P2X1 receptors suggest that these receptors may mediate ATP induced vasodilation in skeletal muscle. Key words: Skeletal Muscle...

  20. Differential expression of ATP7A, ATP7B and CTR1 in adult rat dorsal root ganglion tissue

    Directory of Open Access Journals (Sweden)

    Ip Virginia


    Full Text Available Abstract Background ATP7A, ATP7B and CTR1 are metal transporting proteins that control the cellular disposition of copper and platinum drugs, but their expression in dorsal root ganglion (DRG tissue and their role in platinum-induced neurotoxicity are unknown. To investigate the DRG expression of ATP7A, ATP7B and CTR1, lumbar DRG and reference tissues were collected for real time quantitative PCR, RT-PCR, immunohistochemistry and Western blot analysis from healthy control adult rats or from animals treated with intraperitoneal oxaliplatin (1.85 mg/kg or drug vehicle twice weekly for 8 weeks. Results In DRG tissue from healthy control animals, ATP7A mRNA was clearly detectable at levels similar to those found in the brain and spinal cord, and intense ATP7A immunoreactivity was localised to the cytoplasm of cell bodies of smaller DRG neurons without staining of satellite cells, nerve fibres or co-localisation with phosphorylated heavy neurofilament subunit (pNF-H. High levels of CTR1 mRNA were detected in all tissues from healthy control animals, and strong CTR1 immunoreactivity was associated with plasma membranes and vesicular cytoplasmic structures of the cell bodies of larger-sized DRG neurons without co-localization with ATP7A. DRG neurons with strong expression of ATP7A or CTR1 had distinct cell body size profiles with minimal overlap between them. Oxaliplatin treatment did not alter the size profile of strongly ATP7A-immunoreactive neurons but significantly reduced the size profile of strongly CTR1-immunoreactive neurons. ATP7B mRNA was barely detectable, and no specific immunoreactivity for ATP7B was found, in DRG tissue from healthy control animals. Conclusions In conclusion, adult rat DRG tissue exhibits a specific pattern of expression of copper transporters with distinct subsets of peripheral sensory neurons intensely expressing either ATP7A or CTR1, but not both or ATP7B. The neuron subtype-specific and largely non

  1. Exercise Training positively modulates the Ectonucleotidase Enzymes in Lymphocytes of Metabolic Syndrome Patients. (United States)

    Martins, C C; Bagatini, M D; Cardoso, A M; Zanini, D; Abdalla, F H; Baldissarelli, J; Dalenogare, D P; Dos Santos, D L; Schetinger, M R C; Morsch, V M M


    In this study, we investigated the cardiovascular risk factors as well as ectonucleotidase activities in lymphocytes of metabolic syndrome (MetS) patients before and after an exercise intervention. 20 MetS patients, who performed regular concurrent exercise training for 30 weeks, 3 times/week, were studied. Anthropometric, biochemical, inflammatory and hepatic parameters and hydrolysis of adenine nucleotides and nucleoside in lymphocytes were collected from patients before and after 15 and 30 weeks of the exercise intervention as well as from participants of the control group. An increase in the hydrolysis of ATP and ADP, and a decrease in adenosine deamination in lymphocytes of MetS patients before the exercise intervention were observed (Pexercise training after 30 weeks of intervention. Additionally, exercise training reduced the inflammatory and hepatic markers to baseline levels after 30 weeks of exercise. Our results clearly indicated alteration in ectonucleotidase enzymes in lymphocytes in the MetS, whereas regular exercise training had a protective effect on the enzymatic alterations and on inflammatory and hepatic parameters, especially if it is performed regularly and for a long period. © Georg Thieme Verlag KG Stuttgart · New York.

  2. Model study of ATP and ADP buffering, transport of Ca(2+) and Mg(2+), and regulation of ion pumps in ventricular myocyte (United States)

    Michailova, A.; McCulloch, A.


    We extended the model of the ventricular myocyte by Winslow et al. (Circ. Res 1999, 84:571-586) by incorporating equations for Ca(2+) and Mg(2+) buffering and transport by ATP and ADP and equations for MgATP regulation of ion transporters (Na(+)-K(+) pump, sarcolemmal and sarcoplasmic Ca(2+) pumps). The results indicate that, under normal conditions, Ca(2+) binding by low-affinity ATP and diffusion of CaATP may affect the amplitude and time course of intracellular Ca(2+) signals. The model also suggests that a fall in ATP/ADP ratio significantly reduces sarcoplasmic Ca(2+) content, increases diastolic Ca(2+), lowers systolic Ca(2+), increases Ca(2+) influx through L-type channels, and decreases the efficiency of the Na(+)/Ca(2+) exchanger in extruding Ca(2+) during periodic voltage-clamp stimulation. The analysis suggests that the most important reason for these changes during metabolic inhibition is the down-regulation of the sarcoplasmic Ca(2+)-ATPase pump by reduced diastolic MgATP levels. High Ca(2+) concentrations developed near the membrane might have a greater influence on Mg(2+), ATP, and ADP concentrations than that of the lower Ca(2+) concentrations in the bulk myoplasm. The model predictions are in general agreement with experimental observations measured under normal and pathological conditions.

  3. Quantal release of ATP from clusters of PC12 cells. (United States)

    Fabbro, Alessandra; Skorinkin, Andrei; Grandolfo, Micaela; Nistri, Andrea; Giniatullin, Rashid


    Although ATP is important for intercellular communication, little is known about the mechanism of endogenous ATP release due to a dearth of suitable models. Using PC12 cells known to express the P2X2 subtype of ATP receptors and to store ATP with catecholamines inside dense-core vesicles, we found that clusters of PC12 cells cultured for 3-7 days generated small transient inward currents (STICs) after an inward current elicited by exogenous ATP. The amplitude of STICs in individual cells correlated with the peak amplitude of ATP-induced currents. STICs appeared as asynchronous responses (approximately 20 pA average amplitude) for 1-20 s and were investigated with a combination of patch clamping, Ca2+ imaging, biochemistry and electron microscopy. Comparable STICs were produced by focal KCl pulses and were dependent on extracellular Ca2+. STICs were abolished by the P2X antagonist PPADS and potentiated by Zn2+, suggesting they were mediated by P2X2 receptor activation. The highest probability of observing STICs was after the peak of intracellular Ca2+ increase caused by KCl. Biochemical measurements indicated that KCl application induced a significant release of ATP from PC12 cells. Electron microscopy studies showed narrow clefts without 'synaptic-like' densities between clustered cells. Our data suggest that STICs were caused by quantal release of endogenous ATP by depolarized PC12 cells in close juxtaposition to the recorded cell. Thus, STICs may be a new experimental model to characterize the physiology of vesicular release of ATP and to study the kinetics and pharmacology of P2X2 receptor-mediated quantal currents.

  4. T-lymphocyte dependency of B-lymphocyte blastogenic response to phytomitogens

    International Nuclear Information System (INIS)

    Han, T.; Dadey, B.


    Human peripheral blood T and B lymphocytes were separated by a method based on the stable rosette formation of T lymphocytes with neuraminidase-treated sheep erythrocytes, followed by centrifugation over a Ficoll-Hypaque gradient. Monocytes were isolated from the T-depleted B lymphocyte preparation by allowing the monocytes to ingest iron particles and by subsequent centrifugation over a Ficoll-Hypaque gradient. The T lymphocytes responded extremely well to PHA and very well to PWM, while the B lymphocytes were unresponsive to either PHA or PWM. However, when the B lymphocytes were cultured together with irradiated autologous or allogeneic T lymphocytes (1 : 1,1:2 or 1 : 4 ratio), both PHA and PWM became mitogenic to B lymphocytes. Irradiated T lymphocytes alone did not respond to either PHA or PWM, indicating that the 3 H-thymidine incorporation seen in the mixed-cell culture was due to the activation of unirradiated B lymphocytes. The B lymphocytes failed to respond to these phytomitogens in the presence of lower concentrations of irradiated T lymphocytes. The monocytes were found to be incapable of helping the B lymphocytes to respond to PHA or PWM. (author)

  5. Spectrographic study of neodymium complexing with ATP and ADP

    International Nuclear Information System (INIS)

    Svetlova, I.E.; Dobrynina, N.A.; Martynenko, L.N.


    By spectrographic method neodymium complexing with ATP and ADP in aqueous solutions at different pH values has been studied. The composition of the complexes was determined by the method of isomolar series. On the basis of analysis of absorption spectra it has been ascertained that at equimolar ratio of Nd 3+ and ATP absorption band of L278A corresponds to monocomplex, and the band of 4290 A - to biscomplex. For the complexes with ADP the absorption band of 4288 A is referred to bicomplexes. The character of ATP and ADP coordination by Nd 3+ ion is considered. Stability constants of the complexes are calculated

  6. Opinion: Interactions of innate and adaptive lymphocytes (United States)

    Gasteiger, Georg; Rudensky, Alexander Y.


    Innate lymphocytes, including natural killer (NK) cells and the recently discovered innate lymphoid cells (ILCs) have crucial roles during infection, tissue injury and inflammation. Innate signals regulate the activation and homeostasis of innate lymphocytes. Less well understood is the contribution of the adaptive immune system to the orchestration of innate lymphocyte responses. We review our current understanding of the interactions between adaptive and innate lymphocytes, and propose a model in which adaptive T cells function as antigen-specific sensors for the activation of innate lymphocytes to amplify and instruct local immune responses. We highlight the potential role of regulatory and helper T cells in these processes and discuss major questions in the emerging area of crosstalk between adaptive and innate lymphocytes. PMID:25132095

  7. An ATP synthase harboring an atypical γ-subunit is involved in ATP synthesis in tomato fruit chromoplasts. (United States)

    Pateraki, Irini; Renato, Marta; Azcón-Bieto, Joaquín; Boronat, Albert


    Chromoplasts are non-photosynthetic plastids specialized in the synthesis and accumulation of carotenoids. During fruit ripening, chloroplasts differentiate into photosynthetically inactive chromoplasts in a process characterized by the degradation of the thylakoid membranes, and by the active synthesis and accumulation of carotenoids. This transition renders chromoplasts unable to photochemically synthesize ATP, and therefore these organelles need to obtain the ATP required for anabolic processes through alternative sources. It is widely accepted that the ATP used for biosynthetic processes in non-photosynthetic plastids is imported from the cytosol or is obtained through glycolysis. In this work, however, we show that isolated tomato (Solanum lycopersicum) fruit chromoplasts are able to synthesize ATP de novo through a respiratory pathway using NADPH as an electron donor. We also report the involvement of a plastidial ATP synthase harboring an atypical γ-subunit induced during ripening, which lacks the regulatory dithiol domain present in plant and algae chloroplast γ-subunits. Silencing of this atypical γ-subunit during fruit ripening impairs the capacity of isolated chromoplast to synthesize ATP de novo. We propose that the replacement of the γ-subunit present in tomato leaf and green fruit chloroplasts by the atypical γ-subunit lacking the dithiol domain during fruit ripening reflects evolutionary changes, which allow the operation of chromoplast ATP synthase under the particular physiological conditions found in this organelle. © 2013 The Authors The Plant Journal © 2013 Blackwell Publishing Ltd.

  8. Damage of lymphocytes by ionizing irradiation

    International Nuclear Information System (INIS)

    Rose, H.; Moldenhauer, H.; Kehrberg, G.


    After a short review, how lymphocytes of the peripheral blood are influenced by radiotherapy, the damage of lymphocytes by whole-body irradiation is pointed out in animal experiments and after in vitro irradiation. The special sensibility of B-cells and their homogeneity in fields of radiobiology are opposed to the heterogeneity of T-cells. The radiosensibility of cytotoxic lymphocytes, suppressor cells, and helper cells are discussed. It appears, that within these functional criteria, there is a different radiosensibility, too. (author)

  9. Inhibitors of the 5-lipoxygenase arachidonic acid pathway induce ATP release and ATP-dependent organic cation transport in macrophages. (United States)

    da Silva-Souza, Hercules Antônio; Lira, Maria Nathalia de; Costa-Junior, Helio Miranda; da Cruz, Cristiane Monteiro; Vasconcellos, Jorge Silvio Silva; Mendes, Anderson Nogueira; Pimenta-Reis, Gabriela; Alvarez, Cora Lilia; Faccioli, Lucia Helena; Serezani, Carlos Henrique; Schachter, Julieta; Persechini, Pedro Muanis


    We have previously described that arachidonic acid (AA)-5-lipoxygenase (5-LO) metabolism inhibitors such as NDGA and MK886, inhibit cell death by apoptosis, but not by necrosis, induced by extracellular ATP (ATPe) binding to P2X7 receptors in macrophages. ATPe binding to P2X7 also induces large cationic and anionic organic molecules uptake in these cells, a process that involves at least two distinct transport mechanisms: one for cations and another for anions. Here we show that inhibitors of the AA-5-LO pathway do not inhibit P2X7 receptors, as judged by the maintenance of the ATPe-induced uptake of fluorescent anionic dyes. In addition, we describe two new transport phenomena induced by these inhibitors in macrophages: a cation-selective uptake of fluorescent dyes and the release of ATP. The cation uptake requires secreted ATPe, but, differently from the P2X7/ATPe-induced phenomena, it is also present in macrophages derived from mice deficient in the P2X7 gene. Inhibitors of phospholipase A2 and of the AA-cyclooxygenase pathway did not induce the cation uptake. The uptake of non-organic cations was investigated by measuring the free intracellular Ca(2+) concentration ([Ca(2+)]i) by Fura-2 fluorescence. NDGA, but not MK886, induced an increase in [Ca(2+)]i. Chelating Ca(2+) ions in the extracellular medium suppressed the intracellular Ca(2+) signal without interfering in the uptake of cationic dyes. We conclude that inhibitors of the AA-5-LO pathway do not block P2X7 receptors, trigger the release of ATP, and induce an ATP-dependent uptake of organic cations by a Ca(2+)- and P2X7-independent transport mechanism in macrophages. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Direct ATP photolabeling of Escherichia coli recA proteins: identification of regions required for ATP binding

    International Nuclear Information System (INIS)

    Banks, G.R.; Sedgwick, S.G.


    When the Escherichia coli RecA protein is UV irradiated in the presence of [alpha- 32 P]ATP, a labeled protein--ATP adduct is formed. All the experimental evidence indicates that, in forming such an adduct, the ATP becomes specifically immobilized in the catalytically relevant ATP binding site. The adduct can also be identified after irradiation of E. coli cell lysates in a similar manner. This direct ATP photolabeling of RecA proteins has been used to identify regions of the polypeptide chain involved in the binding of ATP. The photolabeling of a RecA protein that lacks wild-type carboxy-terminal amino acids is not detectable. A RecA protein in which the amino-terminal sequence NH2-Ala-Ile-Asp-Glu-Asn- is replaced by NH2-Thr-Met-Ile-Thr-Asn-Ser-Ser-Ser- is only about 5% as efficiently photolabeled as the wild-type protein. Both of these RecA protein constructions, however, contain all the elements previously implicated, directly or indirectly, in the binding of ATP. ATP-photolabeled RecA protein has also been chemically cleaved at specific amino acids in order to identify regions of the polypeptide chain to which the nucleotide becomes covalently photolinked. The evidence is consistent with a region comprising amino acids 116-170. Thus, this work and that of others suggest that several disparate regions of the unfolded polypeptide chain may combine to form the ATP binding site upon protein folding or may influence binding through long-range effects

  11. Liver ischemia and ischemia-reperfusion induces and trafficks the multi-specific metal transporter Atp7b to bile duct canaliculi: possible preferential transport of iron into bile. (United States)

    Goss, John A; Barshes, Neal R; Karpen, Saul J; Gao, Feng-Qin; Wyllie, Samuel


    Both Atp7b (Wilson disease gene) and Atp7a (Menkes disease gene) have been reported to be trafficked by copper. Atp7b is trafficked to the bile duct canaliculi and Atp7a to the plasma membrane. Whether or not liver ischemia or ischemia-reperfusion modulates Atp7b expression and trafficking has not been reported. In this study, we report for the first time that the multi-specific metal transporter Atp7b is significantly induced and trafficked by both liver ischemia alone and liver ischemia-reperfusion, as judged by immunohistochemistry and Western blot analyses. Although hepatocytes also stained for Atp7b, localized intense staining of Atp7b was found on bile duct canaliculi. Inductive coupled plasma-mass spectrometry analysis of bile copper, iron, zinc, and manganese found a corresponding significant increase in biliary iron. In our attempt to determine if the increased biliary iron transport observed may be a result of altered bile flow, lysosomal trafficking, or glutathione biliary transport, we measured bile flow, bile acid phosphatase activity, and glutathione content. No significant difference was found in bile flow, bile acid phosphatase activity, and glutathione, between control livers and livers subjected to ischemia-reperfusion. Thus, we conclude that liver ischemia and ischemia-reperfusion induction and trafficking Atp7b to the bile duct canaliculi may contribute to preferential iron transport into bile.

  12. Radiation sensitivity of human malignant lymphocytes

    International Nuclear Information System (INIS)

    Seshadri, R.; Matthews, C.; Morley, A.A.


    A simple and rapid in vitro technique to assess the sensitivity of human malignant lymphocytes to roentgen irradiation is described. A variety of established malignant lymphocyte cell lines were cloned in microwells and clone survival was used as the end-point. The survival of the clonogenic malignant lymphocyte down to a fraction of approximately 0.001 could be measured accurately. Except for a T-cell line, the radiation sensitivities of the cell lines were similar to that of normal T-lymphocytes. (orig.)

  13. Autoimmune hepatitis in association with lymphocytic colitis.

    LENUS (Irish Health Repository)

    Cronin, Edmond M


    Autoimmune hepatitis is a rare, chronic inflammatory disorder which has been associated with a number of other auto-immune conditions. However, there are no reports in the medical literature of an association with microscopic (lymphocytic) colitis. We report the case of a 53-year-old woman with several autoimmune conditions, including lymphocytic colitis, who presented with an acute hepatitis. On the basis of the clinical features, serology, and histopathology, we diagnosed autoimmune hepatitis. To our knowledge, this is the first report of autoimmune hepatitis in association with lymphocytic colitis, and lends support to the theory of an autoimmune etiology for lymphocytic colitis.

  14. Effects of spermine NONOate and ATP on the thermal stability of hemoglobin

    Directory of Open Access Journals (Sweden)

    Bassam Rasha


    Full Text Available Abstract Background Minor changes in protein structure induced by small organic and inorganic molecules can result in significant metabolic effects. The effects can be even more profound if the molecular players are chemically active and present in the cell in considerable amounts. The aim of our study was to investigate effects of a nitric oxide donor (spermine NONOate, ATP and sodium/potassium environment on the dynamics of thermal unfolding of human hemoglobin (Hb. The effect of these molecules was examined by means of circular dichroism spectrometry (CD in the temperature range between 25°C and 70°C. The alpha-helical content of buffered hemoglobin samples (0.1 mg/ml was estimated via ellipticity change measurements at a heating rate of 1°C/min. Results Major results were: 1 spermine NONOate persistently decreased the hemoglobin unfolding temperature Tuirrespectively of the Na + /K + environment, 2 ATP instead increased the unfolding temperature by 3°C in both sodium-based and potassium-based buffers and 3 mutual effects of ATP and NO were strongly influenced by particular buffer ionic compositions. Moreover, the presence of potassium facilitated a partial unfolding of alpha-helical structures even at room temperature. Conclusion The obtained data might shed more light on molecular mechanisms and biophysics involved in the regulation of protein activity by small solutes in the cell.

  15. The effect of pH on bromelain partition from Ananas comosus by PEG4000/phosphate ATPS

    Directory of Open Access Journals (Sweden)

    Juliana Ferrari Ferreira


    Full Text Available In this work, the thermodynamic equilibrium and applying of PEG4000/Phosphate ATPS on the purification of bromelain extracted from pineapple was studied. A rigorous study of the equilibrium curves and tie-line length from PEG4000/phosphate ATPS were done for the pH 6-11 at 25ºC. Results showed that there was augment in the PEG and salt contents with the high pH value from PEG4000/Phosphate ATPS and two-phase formation needed only increasing the PEG content. Two tie-line length at pH 11 from PEG4000/Phosphate ATPS were optimal condition for bromelain purification, one on composition of 14% PEG and 13% salt and other at 12.6% PEG and 12.2% salt, while a 25-62 folds of enzyme was found. SDS-PAGE electrophoreses had one band only, which showed that bromelain was purified. Optimum conditions of bromelain use were found at pH 7 and between 30-40ºC.

  16. Optimized Mitochondrial Targeting of Proteins Encoded by Modified mRNAs Rescues Cells Harboring Mutations in mtATP6

    Directory of Open Access Journals (Sweden)

    Randall Marcelo Chin


    Full Text Available Summary: Mitochondrial disease may be caused by mutations in the protein-coding genes of the mitochondrial genome. A promising strategy for treating such diseases is allotopic expression—the translation of wild-type copies of these proteins in the cytosol, with subsequent translocation into the mitochondria, resulting in rescue of mitochondrial function. In this paper, we develop an automated, quantitative, and unbiased screening platform to evaluate protein localization and mitochondrial morphology. This platform was used to compare 31 mitochondrial targeting sequences and 15 3′ UTRs in their ability to localize up to 9 allotopically expressed proteins to the mitochondria and their subsequent impact on mitochondrial morphology. Taking these two factors together, we synthesized chemically modified mRNAs that encode for an optimized allotopic expression construct for mtATP6. These mRNAs were able to functionally rescue a cell line harboring the 8993T > G point mutation in the mtATP6 gene. : Allotopic expression of proteins normally encoded by mtDNA is a promising therapy for mitochondrial disease. Chin et al. use an unbiased and high-content imaging-based screening platform to optimize allotopic expression. Modified mRNAs encoding for the optimized allotopic expression constructs rescued the respiration and growth of mtATP6-deficient cells. Keywords: mitochondria, mitochondrial disease, mRNA, modified mRNA, ATP6, allotopic expression, rare disease, gene therapy, screening, high content imaging

  17. Lymphocytes on sounding rocket flights. (United States)

    Cogoli-Greuter, M; Pippia, P; Sciola, L; Cogoli, A


    Cell-cell interactions and the formation of cell aggregates are important events in the mitogen-induced lymphocyte activation. The fact that the formation of cell aggregates is only slightly reduced in microgravity suggests that cells are moving and interacting also in space, but direct evidence was still lacking. Here we report on two experiments carried out on a flight of the sounding rocket MAXUS 1B, launched in November 1992 from the base of Esrange in Sweden. The rocket reached the altitude of 716 km and provided 12.5 min of microgravity conditions.

  18. ( Atp9) gene between cytoplasmic male sterile line and its ...

    African Journals Online (AJOL)



    Sep 7, 2011 ... Soybean Research Institute of Nanjing Agricultural University, National Center for Soybean .... All these transgenic experiments confirmed the correlation ... editing of ATP synthase subunit 9 mRNA using wheat mitochondrial.

  19. Motor pathway excitability in ATP13A2 mutation carriers

    DEFF Research Database (Denmark)

    Zittel, S; Kroeger, J; van der Vegt, J P M


    OBJECTIVE: To describe excitability of motor pathways in Kufor-Rakeb syndrome (PARK9), an autosomal recessive nigro-striatal-pallidal-pyramidal neurodegeneration caused by a mutation in the ATP13A2 gene, using transcranial magnetic stimulation (TMS). METHODS: Five members of a Chilean family...... with an ATP13A2 mutation (one affected mutation carrier (MC) with a compound heterozygous mutation, 4 asymptomatic MC with a single heterozygous mutation) and 11 healthy subjects without mutations were studied. We measured motor evoked potentials (MEP), the contralateral silent period (cSP), short interval....... RESULTS: CSP duration was increased in the symptomatic ATP13A2 MC. The iSP measurements revealed increased interhemispheric inhibition in both the compound heterozygous and the heterozygous MC. CONCLUSION: A compound heterozygous mutation in the ATP13A2 gene is associated with increased intracortical...

  20. Highly divergent mitochondrial ATP synthase complexes in Tetrahymena thermophila.

    Directory of Open Access Journals (Sweden)

    Praveen Balabaskaran Nina


    Full Text Available The F-type ATP synthase complex is a rotary nano-motor driven by proton motive force to synthesize ATP. Its F(1 sector catalyzes ATP synthesis, whereas the F(o sector conducts the protons and provides a stator for the rotary action of the complex. Components of both F(1 and F(o sectors are highly conserved across prokaryotes and eukaryotes. Therefore, it was a surprise that genes encoding the a and b subunits as well as other components of the F(o sector were undetectable in the sequenced genomes of a variety of apicomplexan parasites. While the parasitic existence of these organisms could explain the apparent incomplete nature of ATP synthase in Apicomplexa, genes for these essential components were absent even in Tetrahymena thermophila, a free-living ciliate belonging to a sister clade of Apicomplexa, which demonstrates robust oxidative phosphorylation. This observation raises the possibility that the entire clade of Alveolata may have invented novel means to operate ATP synthase complexes. To assess this remarkable possibility, we have carried out an investigation of the ATP synthase from T. thermophila. Blue native polyacrylamide gel electrophoresis (BN-PAGE revealed the ATP synthase to be present as a large complex. Structural study based on single particle electron microscopy analysis suggested the complex to be a dimer with several unique structures including an unusually large domain on the intermembrane side of the ATP synthase and novel domains flanking the c subunit rings. The two monomers were in a parallel configuration rather than the angled configuration previously observed in other organisms. Proteomic analyses of well-resolved ATP synthase complexes from 2-D BN/BN-PAGE identified orthologs of seven canonical ATP synthase subunits, and at least 13 novel proteins that constitute subunits apparently limited to the ciliate lineage. A mitochondrially encoded protein, Ymf66, with predicted eight transmembrane domains could be a

  1. Fish Lymphocytes: An Evolutionary Equivalent of Mammalian Innate-Like Lymphocytes?

    Directory of Open Access Journals (Sweden)

    Giuseppe Scapigliati


    Full Text Available Lymphocytes are the responsible of adaptive responses, as they are classically described, but evidence shows that subpopulations of mammalian lymphocytes may behave as innate-like cells, engaging non-self rapidly and without antigen presentation. The innate-like lymphocytes of mammals have been mainly identified as γδT cells and B1-B cells, exert their activities principally in mucosal tissues, may be involved in human pathologies and their functions and tissue(s of origin are not fully understood. Due to similarities in the morphology and immunobiology of immune system between fish and mammals, and to the uniqueness of having free-living larval stages where the development can be precisely monitored and engineered, teleost fish are proposed as an experimental model to investigate human immunity. However, the homology between fish lymphocytes and mammalian innate-like lymphocytes is an issue poorly considered in comparative immunology. Increasing experimental evidence suggests that fish lymphocytes could have developmental, morphological, and functional features in common with innate-like lymphocytes of mammals. Despite such similarities, information on possible links between conventional fish lymphocytes and mammalian innate-like lymphocytes is missing. The aim of this review is to summarize and describe available findings about the similarities between fish lymphocytes and mammalian innate-like lymphocytes, supporting the hypothesis that mammalian γδT cells and B1-B cells could be evolutionarily related to fish lymphocytes.

  2. Discrimination of human cytotoxic lymphocytes from regulatory and B-lymphocytes by orthogonal light scattering

    NARCIS (Netherlands)

    Terstappen, Leonardus Wendelinus Mathias Marie; de Grooth, B.G.; ten Napel, C.H.H.; van Berkel, W.; Greve, Jan


    Light scattering properties of human lymphocyte subpopulations selected by immunofluorescence were studied with a flow cytometer. Regulatory and B-lymphocytes showed a low orthogonal light scatter signal, whereas cytotoxic lymphocytes identified with leu-7, leu-11 and leu-15 revealed a large

  3. Role of ATP in the regulation of cholesterol biogenesis

    International Nuclear Information System (INIS)

    Subba Rao, G.; Ramasarma, T.


    Intraperitoneal administration of glucose (4oomg/rat) stimulated the biogenesis of sterols in starved rats while citrate or pyruvate (20mg/rat) did not have any effect. ATP (10mg/ rat) administered intraperitoneally stimulated the incorporation of acetate-1- 14 C into sterols but not of mevalonate-2- 14 C into sterols in starved rats. The results indicate that ATP may play a role in regulating cholesterol biogenesis and it is not acting merely as an energy source. (author)

  4. Journey in guidelines for lipid management: From adult treatment panel (ATP-I to ATP-III and what to expect in ATP-IV

    Directory of Open Access Journals (Sweden)

    P G Talwalkar


    Full Text Available Adult Treatment Panel (ATP, an expert panel to supervise cholesterol management was set up under the aegis of National Cholesterol Education Program (NCEP in 1985. Since then NCEP-ATP has been revising and framing guidelines to enable clinician to deliver better treatment to cardiovascular patients and to educate general people. As a result, considerable reduction in cardiovascular related deaths has been observed in recent times. All three ATP guidelines viz. ATP-I, ATP-II and ATP-III have targeted low density lipoprotein as their primary goal. The ATP-III guideline was updated in the light of evidences from 5-major clinical trials and was released in 2004. It added therapeutic lifestyle changes, concept of risk equivalents, Framingham CHD-risk score non-high density lipoprotein cholesterol (non-HDL-C as secondary target and gave strong emphasis on metabolic risk factors. The earlier treat-to-target paradigm faced fierce criticism from clinicians across the globe because of insufficient proof of safety and benefits of treating patients with respect to an individual′s low density lipoprotein (LDL level. Further, demonstration of non-HDL-C and total cholesterol/HDL-C ratio as strong predictors of overall cardiovascular risk foresees new guidelines. A tailored-treatment approach was suggested instead of LDL-C target based treatment approach which was soundly based on direct clinical trials evidences and proposes treatment based on individual′s overall 5- to 10-year cardiovascular risk irrespective of LDL-C level, leading to lower number of people on high dose/s of statins. Recent report of the Cholesterol Treatment Trialist′s Collaborators meta-analysis strongly supported primary prevention of LDL with statins in low risk individuals and showed that its benefits completely outweighed its known hazards. Markers other than LDL-C like apolipoprotein B, non-HDL-C and total cholesterol/HDL-C ratio would take precedence in the risk assessment and

  5. Piezo1 regulates mechanotransductive release of ATP from human RBCs. (United States)

    Cinar, Eyup; Zhou, Sitong; DeCourcey, James; Wang, Yixuan; Waugh, Richard E; Wan, Jiandi


    Piezo proteins (Piezo1 and Piezo2) are recently identified mechanically activated cation channels in eukaryotic cells and associated with physiological responses to touch, pressure, and stretch. In particular, human RBCs express Piezo1 on their membranes, and mutations of Piezo1 have been linked to hereditary xerocytosis. To date, however, physiological functions of Piezo1 on normal RBCs remain poorly understood. Here, we show that Piezo1 regulates mechanotransductive release of ATP from human RBCs by controlling the shear-induced calcium (Ca(2+)) influx. We find that, in human RBCs treated with Piezo1 inhibitors or having mutant Piezo1 channels, the amounts of shear-induced ATP release and Ca(2+) influx decrease significantly. Remarkably, a critical extracellular Ca(2+) concentration is required to trigger significant ATP release, but membrane-associated ATP pools in RBCs also contribute to the release of ATP. Our results show how Piezo1 channels are likely to function in normal RBCs and suggest a previously unidentified mechanotransductive pathway in ATP release. Thus, we anticipate that the study will impact broadly on the research of red cells, cellular mechanosensing, and clinical studies related to red cell disorders and vascular disease.

  6. Modification of synthesis nucleotides [γ-32P] ATP

    International Nuclear Information System (INIS)

    Wira Y Rahman; Endang Sarmini; Herlina; Triyanto; Hambali; Abdul Mutalib; Santi Nurbaiti


    In molecular biology, radionuclides in the form of radiolabeled compounds have been widely used as deoxyribonucleic acid (DNA) / ribonucleic acid (RNA) tracer in order to explore a wide range of physiological and pathological processes. One of such compounds is [γ- 32 P]-adenosine triphosphate {[γ- 32 P]-ATP} [γ- 32 P]-ATP which has been widely used in the biotechnology research. In order to support the biotechnology research in Indonesia in this project, [γ- 32 P]- ATP had been synthesized by enzymatic reactions with modifying the method of synthesis using the precursor DL-glyceraldehyde 3-phosphate, nucleotides Adenosine Diphosphate (ADP) and H 3 32 PO 4 and enzymes glyceraldehyde 3-phosphate dehydrogenase, 3-phosphoroglyceric phosphokinase and lactate dehydrogenase. The purification of the synthesized [γ- 32 P]-ATP, by using DEAE Sephadex column chromatography. The synthesis and purification process that had been performed were able in producing of [γ- 32 P]-ATP with radioactivity of 1,175 mCi and radiochemical purity of 99,49%.. Having successfully prepared the [γ- 32 P]-ATP and application, in the near future the Radioisotopes and Radiopharmaceuticals Centre is expected to be able in providing the above-mentioned radiolabeled nucleotide for biotechnology research in Indonesia. (author)

  7. Canine lymphocyte activating factor (LAF)

    International Nuclear Information System (INIS)

    Shifrine, M.; Whaley, C.B.; Wilson, F.D.; Taylor, N.J.


    The immune response of an animal is the sum of the result of the interaction of various cells mainly through soluble mediators. It is not enough to look at specific cell populations, it is also necessary to study the interactions between purified cell population. The effect of one subpopulation on another is via soluble mediators. We have been studying one (of several) such mediators in its relation to radiation effects on the immune response. Lymphocyte activating factor (LAF) is defined functionally as a potentiator of the response of thymocytes to phytohemagglutinin (PHA) or concanavalin (con-A). It can also elicit response of unstimulated subpopulations separated from the thymus. It is a product of adherent populations, presumably macrophages. It has been shown to be produced by human, rabbit, and mouse cells, but has not been reported in the dog. It also was shown to be present in higher concentrations in irradiated mice than in comparable unirradiated mice. We have shown that LAF is produced by plastic-adherent populations derived from peripheral blood. Currently we are working to determine the lymphocyte subpopulations with which LAF interacts

  8. Structural models of the human copper P-type ATPases ATP7A and ATP7B

    DEFF Research Database (Denmark)

    Gourdon, P.; Sitsel, Oleg; Karlsen, J.L.


    The human copper exporters ATP7A and ATP7B contain domains common to all P-type ATPases as well as class-specific features such as six sequential heavy-metal binding domains (HMBD1-HMBD6) and a type-specific constellation of transmembrane helices. Despite the medical significance of ATP7A and ATP7B......, allowing protein-specific properties to be addressed. Furthermore, the mapping of known disease-causing missense mutations indicates that among the heavy-metal binding domains, HMBD5 and HMBD6 are the most crucial for function, thus mimicking the single or dual HMBDs found in most copper-specific P-type...

  9. An ATP synthase harboring an atypical γ-subunit is involved in ATP synthesis in tomato fruit chromoplasts

    DEFF Research Database (Denmark)

    Pateraki, Irini; Renato, Marta; Azcõn-Bieto, Joaquín


    Chromoplasts are non-photosynthetic plastids specialized in the synthesis and accumulation of carotenoids. During fruit ripening, chloroplasts differentiate into photosynthetically inactive chromoplasts in a process characterized by the degradation of the thylakoid membranes, and by the active...... synthesis and accumulation of carotenoids. This transition renders chromoplasts unable to photochemically synthesize ATP, and therefore these organelles need to obtain the ATP required for anabolic processes through alternative sources. It is widely accepted that the ATP used for biosynthetic processes...... in non-photosynthetic plastids is imported from the cytosol or is obtained through glycolysis. In this work, however, we show that isolated tomato (Solanum lycopersicum) fruit chromoplasts are able to synthesize ATP de novo through a respiratory pathway using NADPH as an electron donor. We also report...

  10. Lysosomal Storage of Subunit c of Mitochondrial ATP Synthase in Brain-Specific Atp13a2-Deficient Mice. (United States)

    Sato, Shigeto; Koike, Masato; Funayama, Manabu; Ezaki, Junji; Fukuda, Takahiro; Ueno, Takashi; Uchiyama, Yasuo; Hattori, Nobutaka


    Kufor-Rakeb syndrome (KRS) is an autosomal recessive form of early-onset parkinsonism linked to the PARK9 locus. The causative gene for KRS is Atp13a2, which encodes a lysosomal type 5 P-type ATPase. We recently showed that KRS/PARK9-linked mutations lead to several lysosomal alterations, including reduced proteolytic processing of cathepsin D in vitro. However, it remains unknown how deficiency of Atp13a2 is connected to lysosomal impairments. To address this issue, we analyzed brain tissues of Atp13a2 conditional-knockout mice, which exhibited characteristic features of neuronal ceroid lipofuscinosis, including accumulation of lipofuscin positive for subunit c of mitochondrial ATP synthase, suggesting that a common pathogenic mechanism underlies both neuronal ceroid lipofuscinosis and Parkinson disease. Copyright © 2016 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.


    Directory of Open Access Journals (Sweden)

    F. J. Baêta


    Full Text Available Introduction: Biochemistry, as well as other subjects related to molecular area, have several abstract and difficult concepts to be understood, therefore, many educational innovations have been developed, highlighting the digital games. The digital games feature a playful and motivational character that encourages students during the concepts learning, with a different way to learning the concepts studied. Objectives: The objective of this study was the development of a computer game focused on the concepts of ATP formation, including the glycolytic pathway, Krebs cycle and Electron Transport Chain, as well as aspects related to the regulation, and evaluate the usability of it, as well as some evidence of its educational potential. Material and methods: The development of the game followed the following steps: definition of the subject; understanding of game developer (it was chosen the GameMaker; storyboard creation of the game; prototyping, implementation and usability testing. For the evaluation, inspection usability was performed (without involving end users and subsequently the cognitive route and the usability questionnaire (the latter two with students of the discipline of Biochemistry. Results: The game approached the energy metabolism in three phases: the glycolytic pathway, Krebs cycle and electron transport chain. Each phase has a different purpose, with some questions about the ways. To complete the game, you must correctly answer the questions, avoid the obstacles and achieve the goals of each phase. After usability testing, it found that users could, in a playful manner, actively interact with the content addressed and, through the difficulties presented in the game, had the opportunity to expand and review their knowledge. Conclusions: The game was identified as a motivating and innovative proposal for  teaching, and it had good usability for undergraduate students. The ludic worked as a pedagogical practice encourages student

  12. The Danish National Chronic Lymphocytic Leukemia Registry

    DEFF Research Database (Denmark)

    da Cunha-Bang, Caspar; Geisler, Christian Hartmann; Enggaard, Lisbeth


    AIM: In 2008, the Danish National Chronic Lymphocytic Leukemia Registry was founded within the Danish National Hematology Database. The primary aim of the registry is to assure quality of diagnosis and care of patients with chronic lymphocytic leukemia (CLL) in Denmark. Secondarily, to evaluate...

  13. Lymphocyte-platelet crosstalk in Graves' disease. (United States)

    Kuznik, Boris I; Vitkovsky, Yuri A; Gvozdeva, Olga V; Solpov, Alexey V; Magen, Eli


    Platelets can modulate lymphocytes' role in the pathophysiology of thyroid autoimmune diseases. The present study was performed to clarify the status of platelet-lymphocyte subpopulations aggregation in circulating blood in patients with Graves' disease (GD). One hundred and fifty patients with GD (GD group) and 45 hyperthyroid patients with toxic multinodular goiter (TMG group) were recruited in the study. Control group consisted 150 healthy subjects. Immunophenotyping of lymphocytes was performed by flow cytometry. Detection of lymphocyte-platelet aggregates (LPAs) was done using light microscope after Ficoll-gradient centrifugation. The group of GD patients exhibited reduced CD8 lymphocyte and higher CD19 cell counts compared with TMG group and healthy controls. A greater number of activated CD3, HLA-DR+ lymphocytes were observed in GD than in TMG group and control group. GD group was characterized by lower blood platelet count (232 ± 89 × 10 cells/µL) than TMG group (251 ± 97 × 10 cells/µL; P TMG group (116 ± 67/µL, P < 0.005) and control group (104 ± 58 /µL; P < 0.001). GD is associated with higher levels of activated lymphocytes and lymphocyte-platelet aggregates.

  14. Acetone and Butanone Metabolism of the Denitrifying Bacterium “Aromatoleum aromaticum” Demonstrates Novel Biochemical Properties of an ATP-Dependent Aliphatic Ketone Carboxylase (United States)

    Schühle, Karola


    The anaerobic and aerobic metabolism of acetone and butanone in the betaproteobacterium “Aromatoleum aromaticum” is initiated by their ATP-dependent carboxylation to acetoacetate and 3-oxopentanoic acid, respectively. Both reactions are catalyzed by the same enzyme, acetone carboxylase, which was purified and characterized. Acetone carboxylase is highly induced under growth on acetone or butanone and accounts for at least 5.5% of total cell protein. The enzyme consists of three subunits of 85, 75, and 20 kDa, respectively, in a (αβγ)2 composition and contains 1 Zn and 2 Fe per heterohexamer but no organic cofactors. Chromatographic analysis of the ATP hydrolysis products indicated that ATP was exclusively cleaved to AMP and 2 Pi. The stoichiometry was determined to be 2 ATP consumed per acetone carboxylated. Purified acetone carboxylase from A. aromaticum catalyzes the carboxylation of acetone and butanone as the only substrates. However, the enzyme shows induced (uncoupled) ATPase activity with many other substrates that were not carboxylated. Acetone carboxylase is a member of a protein family that also contains acetone carboxylases of various other organisms, acetophenone carboxylase of A. aromaticum, and ATP-dependent hydantoinases/oxoprolinases. While the members of this family share several characteristic features, they differ with respect to the products of ATP hydrolysis, subunit composition, and metal content. PMID:22020645

  15. Micronuclei in lymphocytes from currently active uranium miners

    International Nuclear Information System (INIS)

    Zoelzer, Friedo; Freitinger Skalicka, Zuzana; Havrankova, Renata; Hon, Zdenek; Rosina, Jozef; Navratil, Leos; Skopek, Jiri


    Micronuclei can be used as markers of past radiation exposure, but only few studies have dealt with uranium miners. In this paper, we report on micronuclei in lymphocytes from individuals currently working at Rozna, Czech Republic, the last functioning uranium mine in the European Union. A modified micronucleus-centromere test was applied to assess the occurrence of micronuclei in stimulated lymphocytes, as well as their content in terms of whole chromosomes or fragments. Compared with unexposed individuals, the miners had higher frequencies of micronucleus-containing lymphocytes and higher percentages of micronuclei without centromeres, and the differences were significant for both parameters (0.74 ± 0.60 vs. 0.50 ± 0.42, p = 0.017 and 49 ± 44 vs. 12 ± 21, p = 0.0002; means ± standard deviations). There were also significant correlations between one or other of these parameters on the one hand and various dose values on the other, in particular with a 'retrievable' dose, that is, a dose whose effect should still be recognisable in lymphocytes assuming a half-life of 3 years. The 'retrievable' dose at which a doubling of the micronucleus frequency was observed was around 35 mSv, corresponding to a total dose of 90 mSv received while working in the mines. Altogether, our data show that the micronucleus-centromere test is a valuable tool for the assessment of past radiation exposure in uranium miners. The scatter in the data is of course far too great to allow individual dosimetry, but for groups of a few dozen exposed individuals, the method can be used to monitor doses clearly below 100 mSv. (orig.)

  16. Assessment of radiation induced apoptosis in lymphocyte subpopulations

    International Nuclear Information System (INIS)

    Perez, M. del R.; Dubner, Diana L.; Michelin, Severino; Gisone, Pablo A.; Barboza, Marcos


    Apoptosis is the main form of radioinduced cell death. The lymphocytes, highly radiosensitive cells, dead in interphase by apoptosis even after very low doses. It has been demonstrated that the various peripheral blood lymphocyte (PBL) types display clear differences in their radiosensitivity . The purpose of this work was the characterization of radioinduced apoptosis in total PBL and in helper and cytotoxic T-lymphocytes. Blood samples were irradiated with a gamma source with doses between 0,5 and 4 Gy, dose-rate 0,8 Gy/min. Apoptosis was evaluated at different times post irradiation (p.i.) by conventional and fluorescence microscopy. Fragmentation of DNA was determined by electrophoresis in agarose gels. Apoptosis was quantified flow cytometrically by light scatter gram and determining the percent of fixed cells stained with propidium iodide that exhibited a reduced DNA content. FITC-labelled Annexin V was used to bind cell membrane phosphatidylserine which is aberrantly exposed during apoptosis. As an additional approach for the evaluation of apoptosis we measured the mitochondrial transmembrane potential by using the cationic dye 3,3 dihexyl oxacarbocyanine iodide (DiOC 6 ). Chromatin condensation and apoptotic bodies were microscopically observed and internucleosomal fragmentation was revealed in electrophoresis gels. Apoptotic cell fraction displayed a dose-dependent increase with a higher radiosensitivity for CD8 T-lymphocytes. These results suggest that quantification of PBL apoptosis could be an useful biological indicator in accidental overexposures and could also provide an useful predictive test for individual radiosensitivity. The higher radiosensitivity revealed by CD8 subset could allow a better discrimination of this phenomenon. (author)

  17. Management of chronic lymphocytic leukemia. (United States)

    Stilgenbauer, Stephan; Furman, Richard R; Zent, Clive S


    Chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL) is usually diagnosed in asymptomatic patients with early-stage disease. The standard management approach is careful observation, irrespective of risk factors unless patients meet the International Workshop on CLL (IWCLL) criteria for "active disease," which requires treatment. The initial standard therapy for most patients combines an anti-CD20 antibody (such as rituximab, ofatumumab, or obinutuzumab) with chemotherapy (fludarabine/cyclophosphamide [FC], bendamustine, or chlorambucil) depending on multiple factors including the physical fitness of the patient. However, patients with very high-risk CLL because of a 17p13 deletion (17p-) with or without mutation of TP53 (17p-/TP53mut) have poor responses to chemoimmunotherapy and require alternative treatment regimens containing B-cell receptor (BCR) signaling pathway inhibitors. The BCR signaling pathway inhibitors (ibrutinib targeting Bruton's tyrosine kinase [BTK] and idelalisib targeting phosphatidyl-inositol 3-kinase delta [PI3K-delta], respectively) are currently approved for the treatment of relapsed/refractory CLL and all patients with 17p- (ibrutinib), and in combination with rituximab for relapsed/refractory patients (idelalisib). These agents offer great efficacy, even in chemotherapy refractory CLL, with increased tolerability, safety, and survival. Ongoing studies aim to determine the best therapy combinations with the goal of achieving long-term disease control and the possibility of developing a curative regimen for some patients. CLL is associated with a wide range of infectious, autoimmune, and malignant complications. These complications result in considerable morbidity and mortality that can be minimized by early detection and aggressive management. This active monitoring requires ongoing patient education, provider vigilance, and a team approach to patient care.

  18. Synthesis and purification of [γP32]-ATP

    International Nuclear Information System (INIS)

    Kukuh, Ratnawati; Santoso, Daniel; Basri, T. Hasan; Natalia Adventini


    The synthesis of [γP 3 2]-ATP has been carried out using an enzymes procedure. The compound was formed by the phosphorylation of ADP during the enzymatic conversion of L-α-glycerol-phosphate to 3-phosphoglycerate. In the present study, lactatedehydrogenase and sodium pyruvat were used in order to maintain β-NAD + concentration and to push the reaction of glyceralaldehyde-3-phosphate dehydrogenase towards the formation of 1,3-diphosphoglycerate. L-α-glycerolphosphate was used as primary substrate, as it is more stable than DL-glyceraldehyde-3-phosphate. The enzymatic reaction was stopped by immersing the reaction vessel in boiling water for about 10 minutes. The labelled [γP 3 2]-ATP formed was separated by thin layer chromatography using PEI-cellulose and the spots of [γP 3 2]-ATP and inorganic P 3 2 residue located by autoradiography using X-ray film. The optimum time for the reaction at room temperature was 90 minutes with a labeling efficiency of 94.9 %. Purification of the [γP 3 2]-ATP by anion exchange chromatography using DEAE sephadex yielded a purity of more than 95%. The results showed that the labeled compound [γP 3 2]-ATP can be synthesized via an enzymatic process with a satisfactory yield. (author), 4 refs, 2 tabs, 2 figs

  19. CFTR mediates noradrenaline-induced ATP efflux from DRG neurons. (United States)

    Kanno, Takeshi; Nishizaki, Tomoyuki


    In our earlier study, noradrenaline (NA) stimulated ATP release from dorsal root ganglion (DRG) neurons as mediated via β(3) adrenoceptors linked to G(s) protein involving protein kinase A (PKA) activation, to cause allodynia. The present study was conducted to understand how ATP is released from DRG neurons. In an outside-out patch-clamp configuration from acutely dissociated rat DRG neurons, single-channel currents, sensitive to the P2X receptor inhibitor PPADS, were evoked by approaching the patch-electrode tip close to a neuron, indicating that ATP is released from DRG neurons, to activate P2X receptor. NA increased the frequency of the single-channel events, but such NA effect was not found for DRG neurons transfected with the siRNA to silence the cystic fibrosis transmembrane conductance regulator (CFTR) gene. In the immunocytochemical study using acutely dissociated rat DRG cells, CFTR was expressed in neurons alone, but not satellite cells, fibroblasts, or Schwann cells. It is concluded from these results that CFTR mediates NA-induced ATP efflux from DRG neurons as an ATP channel.

  20. The Effect of a Grape Seed Extract on Radiation-Induced DNA Damage in Human Lymphocytes (United States)

    Dicu, Tiberius; Postescu, Ion D.; Foriş, Vasile; Brie, Ioana; Fischer-Fodor, Eva; Cernea, Valentin; Moldovan, Mircea; Cosma, Constantin


    Plant-derived antioxidants due to their phenolic compounds content are reported as potential candidates for reducing the levels of oxidative stress in living organisms. Grape seed extracts are very potent antioxidants and exhibit numerous interesting pharmacologic activities. Hydroethanolic (50/50, v/v) standardized extract was obtained from red grape seed (Vitis vinifera, variety Burgund Mare—BM). The total polyphenols content was evaluated by Folin-Ciocalteu procedure and expressed as μEq Gallic Acid/ml. The aim of this study was to evaluate the potential antioxidant effects of different concentrations of BM extract against 60Co γ-rays induced DNA damage in human lymphocytes. Samples of human lymphocytes were incubated with BM extract (12.5, 25.0 and 37.5 μEq GA/ml, respectively) administered at 30 minutes before in vitro irradiation with γ-rays (2 Gy). The DNA damage and repair in lymphocytes were evaluated using alkaline comet assay. Using the lesion score, the radiation-induced DNA damage was found to be significantly different (pextract (except the lymphocytes treated with 37.5 μEq GA/ml BM extract). DNA repair analyzed by incubating the irradiated cells at 37° C and 5% CO2 atmosphere for 2 h, indicated a significant difference (pextract, immediately and two hours after irradiation. These results suggest radioprotective effects after treatment with BM extract in human lymphocytes.

  1. Evolution and phylogeny of B lymphocytes

    Directory of Open Access Journals (Sweden)

    Fabiola Claudio-Piedras


    Full Text Available B lymphocytes are one of the most important cell types involved in the immune response of mammals. The origin and evolution of this cellular type is unknown, but the B lymphocyte bona fide appeared first in fish. In this review we analize the principal components of the immune response of invertebrates, their phylogenetic distribution and the permancence of some properties that allowed the emergence of the B lymphocyte. We started from the idea that many of the components that characterize the B lymphocyte are found distributed among the invertebrates, however, it is in the B lymphocyte, where all these components that give this type of cell its identity, converged. The actual knowledge we have in regards of the lymphocytes comes, in the most part, from physiological studies in mammals, being the mice the more representative. The origin of the B lymphocyte, its alternative mechanisms for generating receptor diversity, its immune effector response, and the generation of memory, require an evolutionary and multidisiplinary approach for its study.

  2. ATP-induced changes in rat skeletal muscle contractility. (United States)

    Gabdrakhmanov, A I; Khayrullin, A E; Grishin, C H; Ziganshin, A U


    Extracellular purine compounds, adenosine triphosphate (ATP) and adenosine, are involved in regulation of many cell functions, engaging in rapid and long-term cellular processes. The nucleotides, including ATP, exert their extracellular effects by influencing membrane P2 receptors. ATP outside of the cell rapidly is metabolized by the ecto-enzyme system to produce adenosine, which acts on separate adenosine (P1) receptors. Since adenosine and ATP often are functional antagonists, ATP degradation not only limits its effect, but also brings new ligand with different, often opposing, properties. Great variety and widespread of P2 and adenosine receptors in the body emphasize the important physiological and pathophysiological significance of these receptors, and make them very attractive as targets for potential drug action.The existence of several subtypes of P2 and adenosine receptors has been shown in the skeletal muscles. ATP as a co-transmitter is densely packed together with classical neurotransmitters in the presynaptic vesicles of vertebral motor units but until recently ATP was refused to have its own functional role there and was recognized only as a source of adenosine. However, on the eve of the third millennium there appeared data that ATP, released from the nerve ending and acting on presynaptic P2 receptors, suppresses subsequent quantum release of acetylcholine. The final product of its degradation, adenosine, performs a similar inhibitory effect acting on presynaptic adenosine receptors.Despite the fact that the mechanisms of presynaptic inhibitory action of ATP and other purines were studied earlier, the object of those studies was usually neuromuscular synapse of cold-blooded animals. The few studies, in which experiments were carried out on preparations of warm-blooded animals, described the basic effects of purines. These often were guided by the convenience of preparation of the synapses of the diaphragm. We think that those results cannot be

  3. ATP measurements for monitoring microbial drinking water quality

    DEFF Research Database (Denmark)

    Vang, Óluva Karin

    Current standard methods for surveillance of microbial drinking water quality are culture based, which are laborious and time-consuming, where results not are available before one to three days after sampling. This means that the water may have been consumed before results on deteriorated water....... The overall aim of this PhD study was to investigate various methodological features of the ATP assay for a potential implementation on a sensor platform as a real-time parameter for continuous on-line monitoring of microbial drinking water quality. Commercial reagents are commonly used to determine ATP......, microbial quality in distributed water, detection of aftergrowth, biofilm formation etc. This PhD project demonstrated that ATP levels are relatively low and fairly stable in drinking water without chlorine residual despite different sampling locations, different drinking water systems and time of year...

  4. Nisin depletes ATP and proton motive force in mycobacteria. (United States)

    Chung, H J; Montville, T J; Chikindas, M L


    This study examined the inhibitory effect of nisin and its mode of action against Mycobacterium smegmatis, a non-pathogenic species of mycobacteria, and M. bovis-Bacill Carmette Guerin (BCG), a vaccine strain of pathogenic M. bovis. In agar diffusion assays, 2.5 mg ml(-1) nisin was required to inhibit M. bovis-BCG. Nisin caused a slow, gradual, time- and concentration-dependent decrease in internal ATP levels in M. bovis-BCG, but no ATP efflux was detected. In mycobacteria, nisin decreased both components of proton motive force (membrane potential, Delta Psi and Delta pH) in a time- and concentration-dependent manner. However, mycobacteria maintained their intracellular ATP levels during the initial time period of Delta Psi and Delta pH dissipation. These data suggest that the mechanism of nisin in mycobacteria is similar to that in food-borne pathogens.

  5. ATP Synthase, a Target for Dementia and Aging? (United States)

    Larrick, James W; Larrick, Jasmine W; Mendelsohn, Andrew R


    Advancing age is the biggest risk factor for development for the major life-threatening diseases in industrialized nations accounting for >90% of deaths. Alzheimer's dementia (AD) is among the most devastating. Currently approved therapies fail to slow progression of the disease, providing only modest improvements in memory. Recently reported work describes mechanistic studies of J147, a promising therapeutic molecule previously shown to rescue the severe cognitive deficits exhibited by aged, transgenic AD mice. Apparently, J147 targets the mitochondrial alpha-F1-ATP synthase (ATP5A). Modest inhibition of the ATP synthase modulates intracellular calcium to activate AMP-activated protein kinase to inhibit mammalian target of rapamycin, a known mechanism of lifespan extension from worms to mammals.

  6. Lymphocytic Pleural Effusion in Acute Melioidosis

    Directory of Open Access Journals (Sweden)

    Kuo-Mou Chung


    Full Text Available An endemic outbreak of melioidosis developed in southern Taiwan following a flood caused by a typhoon in July 2005. A total of 27 patients were diagnosed with the acute and indigenous form of pulmonary melioidosis. Parapneumonic pleural effusions were noted on chest X-rays in six patients. Thoracentesis was done in three patients and all revealed lymphocyte predominance in differential cell count. Burkholderia pseudomallei was isolated in the pleural effusion in one of them. All three patients survived after antibiotic treatment. Lymphocytic pleural effusion is generally seen in tuberculosis or malignancy. However, our findings suggest that melioidosis should be considered in the differential diagnosis of lymphocytic pleural effusion.

  7. Levels of adenine nucleotides (ATP, ADP, AMP) and of inorganic phosphate in needles of Picea abies, representing different stages of development and of pollution dependence

    Energy Technology Data Exchange (ETDEWEB)

    Benz, T; Hampp, R; Horsch, F; Filby, G; Fund, N; Gross, S; Hanisch, B; Kilz, E; Seidel, A [comps.


    Levels of adenine nucleotides (ATP, ADP, AMP) and of inorganic phosphate in needles of Picea abies, representing different stages of development and of pollution dependence. Lyophilized needles of Picea abies (Kaelbelescheuer, southern Black Forest) were analyzed for their content of adenine nucleotides (ATP, ADP, AMP: AdN) and of inorganic phosphate (Psub(i)). The metabolite levels were related to needle age, vegetation period and degree of damage (chlorophyll content). The results were as follows: 1) With increasing needle age there is a general decrease in the total AdN-pool. This decrease is most pronounced in very young needles and occurs in both healthy and damaged tissue. 2) The ATP/ADP-ratio of damaged needle is significantly higher than that of healthy ones. 3) Both phosphorylation potential (ATP.(ADP.Psub(i))/sup -1/) and adenylate energy charge ((ATP + 0.5.ADP).(AdN)/sup -1/) are significantly reduced in damaged needles. This is due to relatively higher levels of Psub(i) and of AMP. The results, although incomplete and preliminary, indicate metabolic alterations which have been described for other tissues in response to pollution by photooxidants.

  8. Diverse Functional Properties of Wilson Disease ATP7B Variants (United States)

    Huster, Dominik; Kühne, Angelika; Bhattacharjee, Ashima; Raines, Lily; Jantsch, Vanessa; Noe, Johannes; Schirrmeister, Wiebke; Sommerer, Ines; Sabri, Osama; Berr, Frieder; Mössner, Joachim; Stieger, Bruno; Caca, Karel; Lutsenko, Svetlana


    BACKGROUND & AIMS Wilson disease is a severe disorder of copper metabolism caused by mutations in ATP7B, which encodes a copper-transporting adenosine triphosphatase. The disease presents with a variable phenotype that complicates the diagnostic process and treatment. Little is known about the mechanisms that contribute to the different phenotypes of the disease. METHODS We analyzed 28 variants of ATP7B from patients with Wilson disease that affected different functional domains; the gene products were expressed using the baculovirus expression system in Sf9 cells. Protein function was analyzed by measuring catalytic activity and copper (64Cu) transport into vesicles. We studied intracellular localization of variants of ATP7B that had measurable transport activities and were tagged with green fluorescent protein in mammalian cells using confocal laser scanning microscopy. RESULTS Properties of ATP7B variants with pathogenic amino-acid substitution varied greatly even if substitutions were in the same functional domain. Some variants had complete loss of catalytic and transport activity, whereas others lost transport activity but retained phosphor-intermediate formation or had partial losses of activity. In mammalian cells, transport-competent variants differed in stability and subcellular localization. CONCLUSIONS Variants in ATP7B associated with Wilson disease disrupt the protein’s transport activity, result in its mislocalization, and reduce its stability. Single assays are insufficient to accurately predict the effects of ATP7B variants the function of its product and development of Wilson disease. These findings will contribute to our understanding of genotype–phenotype correlation and mechanisms of disease pathogenesis. PMID:22240481

  9. Processing mechanics of alternate twist ply (ATP) yarn technology (United States)

    Elkhamy, Donia Said

    Ply yarns are important in many textile manufacturing processes and various applications. The primary process used for producing ply yarns is cabling. The speed of cabling is limited to about 35m/min. With the world's increasing demands of ply yarn supply, cabling is incompatible with today's demand activated manufacturing strategies. The Alternate Twist Ply (ATP) yarn technology is a relatively new process for producing ply yarns with improved productivity and flexibility. This technology involves self plying of twisted singles yarn to produce ply yarn. The ATP process can run more than ten times faster than cabling. To implement the ATP process to produce ply yarns there are major quality issues; uniform Twist Profile and yarn Twist Efficiency. The goal of this thesis is to improve these issues through process modeling based on understanding the physics and processing mechanics of the ATP yarn system. In our study we determine the main parameters that control the yarn twist profile. Process modeling of the yarn twist across different process zones was done. A computational model was designed to predict the process parameters required to achieve a square wave twist profile. Twist efficiency, a measure of yarn torsional stability and bulk, is determined by the ratio of ply yarn twist to singles yarn twist. Response Surface Methodology was used to develop the processing window that can reproduce ATP yarns with high twist efficiency. Equilibrium conditions of tensions and torques acting on the yarns at the self ply point were analyzed and determined the pathway for achieving higher twist efficiency. Mechanistic modeling relating equilibrium conditions to the twist efficiency was developed. A static tester was designed to zoom into the self ply zone of the ATP yarn. A computer controlled, prototypic ATP machine was constructed and confirmed the mechanistic model results. Optimum parameters achieving maximum twist efficiency were determined in this study. The

  10. Results of investigation of trace element content in nucleic acids and histones, isolated from human leucaemic cells

    International Nuclear Information System (INIS)

    Andronikashvili, Eh.L.; Mosulishvili, L.M.; Belokobyl'skij, A.I.; Kharabadze, N.E.; Desai, A.S.; Foley, G.E.; Harvard Cancer Commission, Boston, MA


    Trace metals in purified nucleic acids and histones, extracted from lymphocyte cell culture of patients with acute lymphocytic leukemia or infections mononucleosis and healthy donors were determined with the activation analysis method. In the lymphocyte DNA of patients with infections mononucleosis and healthy donors the content of Co ++ , Sb ++ , Fe +++ , Zn ++ , turned out to be high, while in the lymphoblast DNA of patients with acute lymphocytic leukemia lower concentrations of these metals were detected, with the exception of Co ++ , the content of which is 20 times higher than in the DNA, extracted from the lymphocytes of healthy donors. In the general histone of the leukemic cells the content of the most of trace metals is higher than in the general lymphocyte histone of healthy donors. The exception is Zn ++ , the content of which is lower

  11. Effects of Irradiation on bacterial atp luminous intensity of cooled pork and chicken

    International Nuclear Information System (INIS)

    Ju Hua


    The effect of irradiation on cooled pork and chicken was detected with ATP luminous intensity method. The influences of other factors to ATP luminous intensity were also discussed. There was positive correlation between ATP standard concentration and ATP luminous intensity, and negative correlation between irradiation dosage and ATP luminous intensity. The trend of ATP luminous intensity of cooled pork and chicken after irradiation was inverse S, and the maximum ATP luminous intensity appeared at 6.0 kGy, and minimum at 4.0 and 8.0 kGy. Sterilized water and sterilized pork had no interference to ATP luminous intensity of the samples. There was significant positive correlation between E. coli 10003 concentration and ATP luminous intensity, the coefficient correlation was 0.9437. (authors)

  12. General Information about Chronic Lymphocytic Leukemia (United States)

    ... of the lymph system . Having relatives who are Russian Jews or Eastern European Jews. Signs and symptoms ... information about clinical trials is also available. To Learn More About Chronic Lymphocytic Leukemia For more information ...

  13. Leukemia -- Chronic T-Cell Lymphocytic (United States)

    ... social workers, and patient advocates. Cancer.Net Guide Leukemia - Chronic T-Cell Lymphocytic Introduction Statistics Risk Factors Symptoms and Signs Diagnosis Stages Treatment Options About Clinical Trials Latest Research ...

  14. Neutrophil Lymphocyte Ratio Predicts Postoperative Pain after ...

    African Journals Online (AJOL)


    Feb 7, 2018 ... between preoperatively measured neutrophil-lymphocyte ratio (NLR) – as an inflammation ... analgesic (tenoxicam – as the first drug of choice, paracetamol, tramadol, or pethidine) usage ... fracture fixation). Age, sex, type of ...

  15. Cellular immune therapy for chronic lymphocytic leukemia

    NARCIS (Netherlands)

    Kater, Arnon P.; van Oers, Marinus H. J.; Kipps, Thomas J.


    Although chemotherapy can induce complete responses in patients with chronic lymphocytic leukemia (CLL), it is not considered curative. Treated patients generally develop recurrent disease requiring additional therapy, which can cause worsening immune dysfunction, myelosuppression, and selection for

  16. Lymphocyte mobilization by dextran sulfate in beagles

    International Nuclear Information System (INIS)

    Ragan, H.A.; Debban, K.H.


    Dogs manifesting 239 Pu-induced lymphopenia responded to the lymphocyte-mobilizing agent, dextran sulfate, to a degree similar to that observed in control dogs. No life-threatening increase in prothrombin times or hemorrhagic tendencies were observed

  17. Effect of oral salt loading on blood pressure and lymphocyte sodium metabolism in borderline hypertension

    DEFF Research Database (Denmark)

    Pedersen, K E; Jest, P; Klitgaard, N A


    A randomized double-blind cross-over trial was performed to test the effects of oral salt loading (normal diet + 200 mmol NaCl/day for 4 weeks followed by normal diet + 400 mmol/day for 1 week) against placebo on blood pressure and lymphocyte sodium homeostasis in 10 young borderline hypertensive...... men, genetically predisposed for essential hypertension. Salt loading caused no significant changes in blood pressure levels, lymphocyte sodium content and efflux. In conclusion, our subjects seem insensitive to a few weeks of excessive salt intake....

  18. Chronic Lymphocytic Leukemia: Current Concepts. (United States)

    Yu, Eun-Mi; Kittai, Adam; Tabbara, Imad A


    Chronic lymphocytic leukemia (CLL) is the most common type of leukemia in adults, and while in early, asymptomatic stages treatment is not indicated, the threat to the quality of life and increased mortality of patients posed by more advanced-stage disease necessitate therapeutic intervention. Guidelines of when and how to treat are not well-established because CLL is a disease of the elderly and it is important to balance preservation of functional status and control of the disease. Advances in molecular and genetic profiling has led to the ability to identify sub-groups of patients with CLL whose disease may respond to selected therapy. This review discusses current standard therapies in the major sub-groups of CLL based on age and functional status, in both the front-line and relapsed/refractory settings. It also provides a concise review of novel agents that have shown considerable efficacy in CLL. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  19. How T lymphocytes see antigen (United States)

    Chakraborty, Arup K.


    Complex organisms, like humans, have an adaptive immune system that enables us to do battle with diverse pathogens. This flexible system can also go awry, and many diseases are the direct consequence of the adaptive immune system failing to discriminate between markers of self and non-self. The orchestrators of adaptive immunity are a class of cells called T lymphocytes (T cells). T cells recognize minute numbers of molecular signatures of pathogens, and T cell recognition of these molecular markers of non-self is both specific and degenerate. The specific (yet, cross-reactive), diverse, and self-tolerant T cell repertoire is designed in the thymus. I will describe how an approach that brings together theoretical and computational studies (rooted in statistical physics) with experiments (carried out by key collaborators) has allowed us to shed light on the mechanistic principles underlying how T cells respond to pathogens in a digital fashion (``on'' or ``off''), and how this molecular machinery coupled with frustration (a la spin glasses) plays a key role in designing the special properties of the T cell repertoire during development in the thymus.

  20. Lymphocytic hypophysitis and hypothalamitis - a case report

    International Nuclear Information System (INIS)

    Stelmachowska, M.; Bolko, P.; Wasko, R.; Sowinski, J.; Kosinski, D.; Towpik, I.


    Lymphocytic hypophysitis is an unusual disorder that nearly exclusively affects women. We present a case of 69 year-old female patient who developed the symptoms of diabetes insipidus and partial insufficiency of the anterior pituitary gland. Magnetic resonance imaging of the brain revealed a mass involving the sella and suprasellar region. After exclusion of other causes of infiltrate in this region and due to evident reaction to glucocorticoid treatment the diagnosis of lymphocytic hypophisitis and hypothalamitis was established. (author)

  1. Low-level light therapy potentiates NPe6-mediated photodynamic therapy in a human osteosarcoma cell line via increased ATP. (United States)

    Tsai, Shang-Ru; Yin, Rui; Huang, Ying-Ying; Sheu, Bor-Ching; Lee, Si-Chen; Hamblin, Michael R


    Low-level light therapy (LLLT) is used to stimulate healing, reduce pain and inflammation, and preserve tissue from dying. LLLT has been shown to protect cells in culture from dying after various cytotoxic insults, and LLLT is known to increase the cellular ATP content. Previous studies have demonstrated that maintaining a sufficiently high ATP level is necessary for the efficient induction and execution of apoptosis steps after photodynamic therapy (PDT). We asked whether LLLT would protect cells from cytotoxicity due to PDT, or conversely whether LLLT would enhance the efficacy of PDT mediated by mono-l-aspartyl chlorin(e6) (NPe6). Increased ATP could lead to enhanced cell uptake of NPe6 by the energy dependent process of endocytosis, and also to more efficient apoptosis. In this study, human osteosarcoma cell line MG-63 was subjected to 1.5J/cm(2) of 810nm near infrared radiation (NIR) followed by addition of 10μM NPe6 and after 2h incubation by 1.5J/cm(2) of 652nm red light for PDT. PDT combined with LLLT led to higher cell death and increased intracellular reactive oxygen species compared to PDT alone. The uptake of NPe6 was moderately increased by LLLT, and cellular ATP was increased. The mitochondrial respiratory chain inhibitor antimycin A abrogated the LLLT-induced increase in cytotoxicity. Taken together, these results demonstrate that LLLT potentiates NPe6-mediated PDT via increased ATP synthesis and is a potentially promising strategy that could be applied in clinical PDT. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. SHARPIN Regulates Uropod Detachment in Migrating Lymphocytes

    Directory of Open Access Journals (Sweden)

    Jeroen Pouwels


    Full Text Available SHARPIN-deficient mice display a multiorgan chronic inflammatory phenotype suggestive of altered leukocyte migration. We therefore studied the role of SHARPIN in lymphocyte adhesion, polarization, and migration. We found that SHARPIN localizes to the trailing edges (uropods of both mouse and human chemokine-activated lymphocytes migrating on intercellular adhesion molecule-1 (ICAM-1, which is one of the major endothelial ligands for migrating leukocytes. SHARPIN-deficient cells adhere better to ICAM-1 and show highly elongated tails when migrating. The increased tail lifetime in SHARPIN-deficient lymphocytes decreases the migration velocity. The adhesion, migration, and uropod defects in SHARPIN-deficient lymphocytes were rescued by reintroducing SHARPIN into the cells. Mechanistically, we show that SHARPIN interacts directly with lymphocyte-function-associated antigen-1 (LFA-1, a leukocyte counterreceptor for ICAM-1, and inhibits the expression of intermediate and high-affinity forms of LFA-1. Thus, SHARPIN controls lymphocyte migration by endogenously maintaining LFA-1 inactive to allow adjustable detachment of the uropods in polarized cells.

  3. Limitations of ATP as a measure of microbial biomass

    African Journals Online (AJOL)

    limits the use of ATP as a measure of microbial biomass. S. AIr. J. Zool. 1982, 17: 93 - 95. Beraming van die totale .... only micro-organisms present in the experimental culture, but these were later succeeded by a large ... a value of 49: I by the last day of the experiment. Estimates of the total living biomass of the heterotro-.

  4. Exon duplications in the ATP7A gene

    DEFF Research Database (Denmark)

    Mogensen, Mie; Skjørringe, Tina; Kodama, Hiroko


    the identified duplicated fragments originated from a single or from two different X-chromosomes, polymorphic markers located in the duplicated fragments were analyzed. RESULTS: Partial ATP7A gene duplication was identified in 20 unrelated patients including one patient with Occipital Horn Syndrome (OHS...

  5. Electrochemical Investigation of the Interaction between Catecholamines and ATP. (United States)

    Taleat, Zahra; Estévez-Herrera, Judith; Machado, José D; Dunevall, Johan; Ewing, Andrew G; Borges, Ricardo


    The study of the colligative properties of adenosine 5'-triphosphate (ATP) and catecholamines has received the attention of scientists for decades, as they could explain the capabilities of secretory vesicles (SVs) to accumulate neurotransmitters. In this Article, we have applied electrochemical methods to detect such interactions in vitro, at the acidic pH of SVs (pH 5.5) and examined the effect of compounds having structural similarities that correlate with functional groups of ATP (adenosine, phosphoric acid and sodium phosphate salts) and catecholamines (catechol). Chronoamperometry and fast scan cyclic voltammetry (FSCV) provide evidence compatible with an interaction of the catechol and adenine rings. This interaction is also reinforced by an electrostatic interaction between the phosphate group of ATP and the protonated ammonium group of catecholamines. Furthermore, chronoamperometry data suggest that the presence of ATP subtlety reduces the apparent diffusion coefficient of epinephrine in aqueous media that adds an additional factor leading to a slower rate of catecholamine exocytosis. This adds another plausible mechanism to regulate individual exocytosis events to alter communication.

  6. Supplementary data: Novel mutation in ATP-binding domain of ...

    Indian Academy of Sciences (India)

    Novel mutation in ATP-binding domain of ABCD1 gene in adrenoleucodystrophy. Neeraj Kumar, Krishna K. Taneja, Atul Kumar, Deepti Nayar, Bhupesh Taneja, Satindra Aneja,. Madhuri Behari, Veena Kalra and Surendra K. Bansal. J. Genet. 89, 473–477. Figure 1. Rmsd plot of native and Arg617Ser substituted models.

  7. 'Domino' systems biology and the 'A' of ATP. (United States)

    Verma, Malkhey; Zakhartsev, Maksim; Reuss, Matthias; Westerhoff, Hans V


    We develop a strategic 'domino' approach that starts with one key feature of cell function and the main process providing for it, and then adds additional processes and components only as necessary to explain provoked experimental observations. The approach is here applied to the energy metabolism of yeast in a glucose limited chemostat, subjected to a sudden increase in glucose. The puzzles addressed include (i) the lack of increase in adenosine triphosphate (ATP) upon glucose addition, (ii) the lack of increase in adenosine diphosphate (ADP) when ATP is hydrolyzed, and (iii) the rapid disappearance of the 'A' (adenine) moiety of ATP. Neither the incorporation of nucleotides into new biomass, nor steady de novo synthesis of adenosine monophosphate (AMP) explains. Cycling of the 'A' moiety accelerates when the cell's energy state is endangered, another essential domino among the seven required for understanding of the experimental observations. This new domino analysis shows how strategic experimental design and observations in tandem with theory and modeling may identify and resolve important paradoxes. It also highlights the hitherto unexpected role of the 'A' component of ATP. Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.

  8. ATP stimulates calcium influx in primary astrocyte cultures

    International Nuclear Information System (INIS)

    Neary, J.T.; van Breemen, C.; Forster, E.; Norenberg, L.O.; Norenberg, M.D.


    The effect of ATP and other purines on 45 Ca uptake was studied in primary cultures of rat astrocytes. Treatment of the cells with ATP for 1 to 30 min brought about an increase in cellular 45 Ca. Stimulation of calcium influx by ATP was investigated using a 90 sec exposure to 45 Ca and over a concentration range of 0.1 nM to 3 mM; a biphasic dose-response curve was obtained with EC50 values of 0.3 nM and 9 uM, indicating the presence of low and high affinity purinergic binding sites. Similar levels of 45 Ca influx at 90 sec were observed with ATP, ADP and adenosine (all at 100 uM). Prior treatment of the cultures with LaCl3 blocked the purine-induced 45 Ca influx. These findings indicate that one pathway for calcium entry in astrocytes involves purinergic receptor-operated, calcium channels

  9. Paradox applications integration ATP's for MAC and mass balance programs

    International Nuclear Information System (INIS)

    Russell, V.K.; Mullaney, J.E.


    The K Basins Materials Accounting (MAC) and Material Balance (MBA) database system were set up to run under one common applications program. This Acceptance Test Plan (ATP) describes how the code was to be tested to verify its correctness. The scope of the tests is minimal, since both MAC and MBA have already been tested in detail as stand-alone programs

  10. ATP Production in Chlamydomonas reinhardtii Flagella by Glycolytic Enzymes

    DEFF Research Database (Denmark)

    Mitchell, Beth F; Pedersen, Lotte B; Feely, Michael


    reside in the detergent-soluble (membrane + matrix) compartments. We further show that axonemal enolase is a subunit of the CPC1 central pair complex and that reduced flagellar enolase levels in the cpc1 mutant correlate with the reduced flagellar ATP concentrations and reduced in vivo beat frequencies...

  11. B and T lymphocytes in man. I. Effect of infant thymic irradiation on the circulating B and T lymphocytes

    International Nuclear Information System (INIS)

    Reddy, M.M.; Goh, K.; Hempelmann, L.H.


    B and T lymphocytes were studied in a group of adults whose thymic glands were irradiated in infancy for alleged thymic enlargement. Two independent methods were used to determine the B and T lymphocytes from each peripheral blood specimen: (1) the relative proportion of cells with surface immunoglobulins (B lymphocytes) and cells forming rosettes with sheep erythrocytes (T lymphocytes); and (2) the relative mitogenic response to phytohemagglutinin (T lymphocytes) and to pokeweed mitogen (B lymphocytes). All specimens were coded. The results obtained indicate: (1) a reduction of B and T lymphocytes; and (2) a decreased mitogenic response of lymphocytes to phytohemagglutinin and pokeweed mitogen in this group of patients as compared with the controls. These observations suggest that (1) the effect of irradiation to the thymus gland on lymphocytes is long lasting and (2) both B and T lymphocytes are affected by irradiation to the thymus gland

  12. Low level chemiluminescence measurement of the binding of 8-methoxypsoralen to proteins and lymphocytic surfaces

    International Nuclear Information System (INIS)

    Lange, B.


    Photochemotherapy with 8-methoxypsoralen (8-MOP) and longwave ultraviolet light is beneficial in such different disorders like psoriasis, lichen planus, and mykosis fungoides. In contrast to a widely accepted hypothesis 8-MOP does not solely bind to nucleic acid, but also to certain proteins. The mechanism of this binding as well as the precise binding area are unknown. Therefore the UV-provoked reactions of 8-MOP with a lipid mixture, a glucosaminoglycan solution, a protein solution, and lymphocyte suspensions, respectively were investigated using low level chemiluminescence (LLCL). It was found an 8-MOP concentration-dependent decrease of LLCL intensity in the lymphocyte suspensions (10 3 to 10 4 cells/μl). This effect is result of the diminution of the photoactive 8-MOP content of the solution. 8-MOP binds quickly and in the course of a free radical reaction to lymphocytic surfaces and coincidentally loses its potency to start LLCL-detectable free radical chain responses. (author)

  13. Evidence that Na+/H+ exchanger 1 is an ATP-binding protein. (United States)

    Shimada-Shimizu, Naoko; Hisamitsu, Takashi; Nakamura, Tomoe Y; Wakabayashi, Shigeo


    Na(+)/H(+) exchanger (NHE) 1 is a member of the solute carrier superfamily, which regulates intracellular ionic homeostasis. NHE1 is known to require cellular ATP for its activity, despite there being no requirement for energy input from ATP hydrolysis. In this study, we investigated whether NHE1 is an ATP-binding protein. We designed a baculovirus vector carrying both epitope-tagged NHE1 and its cytosolic subunit CHP1, and expressed the functional NHE1-CHP1 complex on the surface of Sf9 insect cells. Using the purified complex protein consisting of NHE1 and CHP1 from Sf9 cells, we examined a photoaffinity labeling reaction with 8-azido-ATP-biotin. UV irradiation promoted the incorporation of 8-azido-ATP into NHE1, but not into CHP1, with an apparent Kd of 29.1 µM in the presence of Mg(2+). The nonlabeled nucleotides ATP, GTP, TTP and CTP all inhibited this crosslinking. However, ATP had the strongest inhibitory effect, with an apparent inhibition constant (IC50) for ATP of 2.2 mM, close to the ATP concentration giving the half-maximal activation of NHE1 activity. Importantly, crosslinking was more strongly inhibited by ATP than by ADP, suggesting that ATP is dissociated from NHE1 upon ATP hydrolysis. Limited proteolysis with thrombin and deletion mutant analysis revealed that the 8-azido-ATP-binding site is within the C-terminal cytoplasmic domain of NHE1. Equilibrium dialysis with NHE1-derived peptides provided evidence that ATP directly binds to the proximal cytoplasmic region (Gly542-Pro598), which is critical for ATP-dependent regulation of NHE1. These findings suggest that NHE1 is an ATP-binding transporter. Thus, ATP may serve as a direct activator of NHE1. © 2013 The Authors Journal compilation © 2013 FEBS.

  14. How Native and Alien Metal Cations Bind ATP: Implications for Lithium as a Therapeutic Agent (United States)

    Dudev, Todor; Grauffel, Cédric; Lim, Carmay


    Adenosine triphosphate (ATP), the major energy currency of the cell, exists in solution mostly as ATP-Mg. Recent experiments suggest that Mg2+ interacts with the highly charged ATP triphosphate group and Li+ can co-bind with the native Mg2+ to form ATP-Mg-Li and modulate the neuronal purine receptor response. However, it is unclear how the negatively charged ATP triphosphate group binds Mg2+ and Li+ (i.e. which phosphate group(s) bind Mg2+/Li+) and how the ATP solution conformation depends on the type of metal cation and the metal-binding mode. Here, we reveal the preferred ATP-binding mode of Mg2+/Li+ alone and combined: Mg2+ prefers to bind ATP tridentately to each of the three phosphate groups, but Li+ prefers to bind bidentately to the terminal two phosphates. We show that the solution ATP conformation depends on the cation and its binding site/mode, but it does not change significantly when Li+ binds to Mg2+-loaded ATP. Hence, ATP-Mg-Li, like Mg2+-ATP, can fit in the ATP-binding site of the host enzyme/receptor, activating specific signaling pathways.

  15. Structure of the oxalate-ATP complex with pyruvate kinase: ATP as a bridging ligand for the two divalent cations

    International Nuclear Information System (INIS)

    Lodato, D.T.; Reed, G.H.


    The 2 equiv of divalent cation that are required cofactors for pyruvate kinase reside in sites of different affinities for different species of cation. The intrinsic selectivity of the protein-based site for Mn(II) and of the nucleotide-based site for Mg(II) has been exploited in electron paramagnetic resonance (EOR) investigations of ligands for Mn(II) at the protein-based site. Oxalate, a structural analogue of the enolate of pyruvate, has been used as a surrogate for the reactive form of pyruvate in complexes with enzyme, Mn(II), Mg(II), and ATP. Superhyperfine coupling between the unpaired electron spin of Mn(II) and the nuclear spin of 17 O, specifically incorporated into oxalate, shows that oxalate is bound at the active site as a bidentate chelate with Mn(II). Coordination of the γ-phosphate of ATP to this same Mn(II) center is revealed by observation of superhyperfine coupling from 17 O regiospecifically incorporated into the γ-phosphate group of ATP. By contrast, 17 O in the α-phosphate or in the β-phosphate groups of ATP does not influence the spectrum. Experiments in 17 O-enriched water show that there is also a single water ligand bound to the Mn(II). These data indicate that ATP bridges Mn(II) and Mg(II) at the active site. A close spacing of the two divalent cations is also evident from the occurrence of magnetic interactions for complexes in which 2 equiv of Mn(II) are present at the active site. The structure for the enzyme-Mn(II)-oxalate-Mg(II)-ATP complex suggests a scheme for the normal reverse reaction of pyruvate kinase in which the divalent cation at the protein-based site activates the keto acid substrate through chelation and promotes phospho transfer by simultaneous coordination to the enolate oxygen and to a pendant oxygen from the γ-phosphate of ATP

  16. Quantification of newly produced B and T lymphocytes in untreated chronic lymphocytic leukemia patients

    Directory of Open Access Journals (Sweden)

    Caimi Luigi


    Full Text Available Abstract Background The immune defects occurring in chronic lymphocytic leukemia are responsible for the frequent occurrence of infections and autoimmune phenomena, and may be involved in the initiation and maintenance of the malignant clone. Here, we evaluated the quantitative defects of newly produced B and T lymphocytes. Methods The output of B and T lymphocytes from the production and maturation sites was analyzed in chronic lymphocytic leukemia patients and healthy controls by quantifying kappa-deleting recombination excision circles (KRECs and T-cell receptor excision circles (TRECs by a Real-Time PCR assay that simultaneously detects both targets. T-lymphocyte subsets were analyzed by six-color flow cytometric analysis. Data comparison was performed by two-sided Mann-Whitney test. Results KRECs level was reduced in untreated chronic lymphocytic leukemia patients studied at the very early stage of the disease, whereas the release of TRECs+ cells was preserved. Furthermore, the observed increase of CD4+ lymphocytes could be ascribed to the accumulation of CD4+ cells with effector memory phenotype. Conclusions The decreased number of newly produced B lymphocytes in these patients is likely related to a homeostatic mechanism by which the immune system balances the abnormal B-cell expansion. This feature may precede the profound defect of humoral immunity characterizing the later stages of the disease.


    Directory of Open Access Journals (Sweden)

    N. V. Isaeva


    Full Text Available Abstract. A complex immunologic examination of fifty patients with clinically significant postoperative fibrosis has been performed. Immunogram indexes were determined, and activities of basic oxidation-reduction enzymes were investigated in blood lymphocytes. What concerned immune status of the patients under study, some peculiar features have been revealed, with respect to cellular and humoral compartments, i.e., relative increase in CD3+ population, a shift to CD4+ cells in the ratio of lymphocyte subpopulations, higher indexes of immune regulation and phagocytosis, increased IgG level, and lower content of IgA, as compared to appropriate controls. Metabolic parameters of lymphocytes reflect their functional activation, being expressed as an enhanced ability for intracellular synthetic processes, elevated functional activity of lymphocytes, and increased immune response. The general pattern of changes in immune status and metabolic indexes of lymphocytes allow us to assume participation of autoimmune component in progression of epidural fibrosis. The data obtained may be used in combined diagnostics and correction of this disorder. (Med. Immunol., vol. 10, N 6, pp 589-592.

  18. Spatial Organization and Molecular Correlation of Tumor-Infiltrating Lymphocytes Using Deep Learning on Pathology Images

    Directory of Open Access Journals (Sweden)

    Joel Saltz


    Full Text Available Summary: Beyond sample curation and basic pathologic characterization, the digitized H&E-stained images of TCGA samples remain underutilized. To highlight this resource, we present mappings of tumor-infiltrating lymphocytes (TILs based on H&E images from 13 TCGA tumor types. These TIL maps are derived through computational staining using a convolutional neural network trained to classify patches of images. Affinity propagation revealed local spatial structure in TIL patterns and correlation with overall survival. TIL map structural patterns were grouped using standard histopathological parameters. These patterns are enriched in particular T cell subpopulations derived from molecular measures. TIL densities and spatial structure were differentially enriched among tumor types, immune subtypes, and tumor molecular subtypes, implying that spatial infiltrate state could reflect particular tumor cell aberration states. Obtaining spatial lymphocytic patterns linked to the rich genomic characterization of TCGA samples demonstrates one use for the TCGA image archives with insights into the tumor-immune microenvironment. : Tumor-infiltrating lymphocytes (TILs were identified from standard pathology cancer images by a deep-learning-derived “computational stain” developed by Saltz et al. They processed 5,202 digital images from 13 cancer types. Resulting TIL maps were correlated with TCGA molecular data, relating TIL content to survival, tumor subtypes, and immune profiles. Keywords: digital pathology, immuno-oncology, machine learning, lymphocytes, tumor microenvironment, deep learning, tumor-infiltrating lymphocytes, artificial intelligence, bioinformatics, computer vision

  19. The effects of 3-methylcholanthrene on lymphocyte proliferation in the common carp (Cyprinus carpio L.)

    International Nuclear Information System (INIS)

    Reynaud, S.; Deschaux, P.


    The sensitivity of lymphocyte proliferation as bioindicator of pollution stress was evaluated in the common carp (Cyrinus carpio L.). The time course response of peripheral blood leukocyte proliferation in response or not to mitogens was measured from 1 to 7 days after peritoneal injection of 3-methylcholantrene (3-MC), and compared to the time course response of a highly sensitive biomarker, induction of cytochrome P450. 3-Methylcholanthrene (40 mg kg -1 ) inhibited both B- and T-lymphocyte proliferation in response to lipopolysaccharide (LPS) and concanavalin A (Con A). Studies with α-naphtofiavone, suggest the lack of metabolic processes. 3-Methylcholanthrene alone strongly stimulated resting peripheral blood leukocytes (PBLs) proliferation. This effect was not transient. The induction of lymphocyte proliferation paralleled the increase in cytochrome P450 content in the liver. The specificity of polycyclic aromatic hydrocarbon (PAH)-induced lymphocyte proliferation suggests that this immune activity may be an early marker of exposure to PAHs in aquatic environments. The capacity of 3-MC to induce rapid lymphocyte proliferation may be related to PAH-induced rapid clonal expansion in mammals. These results strongly suggested that the underlying mechanism might be the same in both models. More studies are needed in fish to explain this phenomenon and may be helpful in understanding the occurrence of neoplastic epizootics in fish associated with PAH exposition

  20. Loss of the gene for the alpha subunit of ATP synthase (ATP5A1) from the W chromosome in the African grey parrot (Psittacus erithacus). (United States)

    de Kloet, S R


    This study describes the results of an analysis using Southern blotting, the polymerase chain reaction, and sequencing which shows that the African grey parrot (Psittacus erithacus) lacks the W-chromosomal gene for the alpha subunit of mitochondrial ATP synthase (ATP5A1W). Additional evidence shows that in other psittacines a fragment of the ATP5A1W gene contains five times as many nonsynonymous nucleotide replacements as the homologous fragment of the Z gene. Therefore, whereas in these other psittacines the corresponding ATP5A1Z protein fragment is highly conserved and varies by only a few, moderately conservative amino acid substitutions, the homologous ATP5A1W fragments contain a considerable number of, sometimes highly nonconservative, amino acid replacements. In one of these species, the ringneck parakeet (Psittacula krameri), the ATP5A1W gene is present in an inactive form because of the presence of a nonsense codon. Other changes, possibly leading to an inactive ATP5A1W gene product, involve the substitution of arginine residues by cysteine in the ATP5A1W protein of the mitred conure (Aratinga mitrata) and the blue and gold macaw (Ara ararauna). The data suggest also that although the divergence of the psittacine ATP5A1W and ATP5A1Z genes preceded the origin of the psittacidae, this divergence occurred independently of a similar process in the myna (Gracula religiosa), the outgroup used in this study.

  1. Progranulin Inhibits Human T Lymphocyte Proliferation by Inducing the Formation of Regulatory T Lymphocytes

    Directory of Open Access Journals (Sweden)

    Kyu Hwan Kwack


    Full Text Available We have examined the effect of progranulin (PGRN on human T cell proliferation and its underlying mechanism. We show that PGRN inhibits the PHA-induced multiplication of T lymphocytes. It increases the number of iTregs when T lymphocytes are activated by PHA but does not do so in the absence of PHA. PGRN-mediated inhibition of T lymphocyte proliferation, as well as the induction of iTregs, was completely reversed by a TGF-β inhibitor or a Treg inhibitor. PGRN induced TGF-β secretion in the presence of PHA whereas it did not in the absence of PHA. Our findings indicate that PGRN suppresses T lymphocyte proliferation by enhancing the formation of iTregs from activated T lymphocytes in response to TGF-β.

  2. Mechanical Control of ATP Synthase Function: Activation Energy Difference between Tight and Loose Binding Sites

    KAUST Repository

    Beke-Somfai, Tamás; Lincoln, Per; Nordén, Bengt


    Despite exhaustive chemical and crystal structure studies, the mechanistic details of how FoF1-ATP synthase can convert mechanical energy to chemical, producing ATP, are still not fully understood. On the basis of quantum mechanical calculations

  3. Metabolomic Analysis of Differential Changes in Metabolites during ATP Oscillations in Chondrogenesis

    Directory of Open Access Journals (Sweden)

    Hyuck Joon Kwon


    Full Text Available Prechondrogenic condensation is a critical step for skeletal pattern formation. Recent studies reported that ATP oscillations play an essential role in prechondrogenic condensation. However, the molecular mechanism to underlie ATP oscillations remains poorly understood. In the present study, it was investigated how changes in metabolites are implicated in ATP oscillations during chondrogenesis by using capillary electrophoresis time-of-flight mass spectrometry (CE-TOF-MS. CE-TOF-MS detected 93 cationic and 109 anionic compounds derived from known metabolic pathways. 15 cationic and 18 anionic compounds revealed significant change between peak and trough of ATP oscillations. These results implicate that glycolysis, mitochondrial respiration and uronic acid pathway oscillate in phase with ATP oscillations, while PPRP and nucleotides synthesis pathways oscillate in antiphase with ATP oscillations. This suggests that the ATP-producing glycolysis and mitochondrial respiration oscillate in antiphase with the ATP-consuming PPRP/nucleotide synthesis pathway during chondrogenesis.

  4. Crystallization and preliminary X-ray diffraction analysis of an archaeal tRNA-modification enzyme, TiaS, complexed with tRNAIle2 and ATP

    International Nuclear Information System (INIS)

    Osawa, Takuo; Inanaga, Hideko; Kimura, Satoshi; Terasaka, Naohiro; Suzuki, Tsutomu; Numata, Tomoyuki


    A. fulgidus TiaS was cocrystallized with tRNA Ile2 and ATP and X-ray diffraction data were collected to 2.9 Å resolution using a synchrotron-radiation source. The cytidine at the first anticodon position of archaeal tRNA Ile2 , which decodes the isoleucine AUA codon, is modified to 2-agmatinylcytidine (agm 2 C) to guarantee the fidelity of protein biosynthesis. This post-transcriptional modification is catalyzed by tRNA Ile -agm 2 C synthetase (TiaS) using ATP and agmatine as substrates. Archaeoglobus fulgidus TiaS was overexpressed in Escherichia coli cells and purified. tRNA Ile2 was prepared by in vitro transcription with T7 RNA polymerase. TiaS was cocrystallized with both tRNA Ile2 and ATP by the vapour-diffusion method. The crystals of the TiaS–tRNA Ile2 –ATP complex diffracted to 2.9 Å resolution using synchrotron radiation at the Photon Factory. The crystals belonged to the primitive hexagonal space group P3 2 21, with unit-cell parameters a = b = 131.1, c = 86.6 Å. The asymmetric unit is expected to contain one TiaS–tRNA Ile2 –ATP complex, with a Matthews coefficient of 2.8 Å 3 Da −1 and a solvent content of 61%

  5. Flow cytometric analysis of lymphocytes and lymphocyte subpopulations in induced sputum from patients with asthma

    Directory of Open Access Journals (Sweden)

    Yutaro Shiota


    Full Text Available Study objectives were to compare the numbers of lymphocytes and lymphocyte subpopulations in induced sputum from asthmatic patients and from healthy subjects, and to determine the effect of inhaled anti-asthmatic steroid therapy on these cell numbers. Hypertonic saline inhalation was used to non-invasively induce sputum samples in 34 patients with bronchial asthma and 21 healthy subjects. The sputum samples were reduced with dithioerythritol and absolute numbers of lymphocytes and lymphocyte subpopulations were assessed by direct immunofluorescence and flow cytometry. To assess the effect of beclomethasone dipropionate (BDP on induced sputum, numbers of lymphocytes and lymphocyte subpopulations in sputum also were evaluated after 4 weeks of BDP inhalation treatment in seven asthmatic patients. An adequate sample was obtained in 85.3% of patients with asthma and in 79.2% of the healthy subjects. Induced sputum from patients with asthma had increased numbers of lymphocytes (P = 0.009; CD4+ cells (P = 0.044; CD4+ cells-bearing interleukin-2 receptor (CD25; P = 0.016; and CD4+ cells bearing human histocompatibility leukocyte antigen (HLA-DR (P = 0.033. CD8+ cells were not increased in asthmatic patients. In patients treated with inhaled steroids, numbers of lymphocytes, CD4+ cells, CD25-bearing CD4+ cells and HLA-DR-bearing CD4+ cells in sputum decreased from pretreatment numbers (P = 0.016, 0.002, 0.003 and 0.002, respectively. Analysis of lymphocytes in induced sputum by flow cytometry is useful in assessing bronchial inflammation, and activated CD4+ lymphocytes may play a key role in the pathogenesis of airway inflammation in bronchial asthma.


    Directory of Open Access Journals (Sweden)

    L. A. Alekseeva


    Full Text Available Introduction of flow cytometry caused an increase in the investigation of liquor lymphocyte pool phenotype in the case of different brain disorders, including viral and bacterial meningitis, however this type of research in children has been relatively rare. Phenotype and lymphocyte functions are under cytokine control system, therefore detection of interconnections between lymphocyte pool subpopulation composition and cytokine level in blood and liquor of the patients concerns a great interest. The purpose of this research was to study lymphocyte subpopulation composition and the level of cytokines IL-1β, IL-6, IL-8, IL-10, IFNα, IFNγ and IL-4, and also IgG in liquor and blood of children with viral and bacterial meningitis. There was performed blood and liquor investigation in 46 children aged from 1 to 16 years old with viral (n = 35 and bacterial (n = 11 meningitis. Immunophenotyping of blood and liquor cells was performed by the method of flow cytometry with the use of monoclonal antibodies to CD3, CD4, CD8, CD19, CD16, CD56, CD25 and CD95. The content of cytokines was detected in ELISA, and that of IgG — by the method of quantitative immunoturbodimetry. During an acute period of viral meningitis there was detected a decrease in NK portion and activated CD25+ cells in the blood of patients accompanied by the increase in B-lymphocytes number, along with cytokine IFNγ, IL-8 and IL-10 serum level rise. There was determined T-lymphocytes accumulation in liquor with the prevalence of CD4+ Т-cells and, to a lesser degree, CD25+ and CD95+ cells, NK and B-lymphocytes. Intrathecally there was noted the predominance of IL-6 response accompanied by the growth of IL-8 and IL-10 concentration as well. During an acute period of bacterial meningitis there was noted a decrease in percentage of CD3+, CD4+, CD8+ Т-lymphocytes, NK, CD25+ and CD95+ cells, along with, on the contrary, sharp increase in B-cells pool, simultaneously with

  7. Metal ion levels and lymphocyte counts

    DEFF Research Database (Denmark)

    Penny, Jeannette Ø; Varmarken, Jens-Erik; Ovesen, Ole


    BACKGROUND AND PURPOSE: Wear particles from metal-on-metal arthroplasties are under suspicion for adverse effects both locally and systemically, and the DePuy ASR Hip Resurfacing System (RHA) has above-average failure rates. We compared lymphocyte counts in RHA and total hip arthroplasty (THA) an....../ppb. INTERPRETATION: Circulating T-lymphocyte levels may decline after surgery, regardless of implant type. Metal ions-particularly cobalt-may have a general depressive effect on T- and B-lymphocyte levels. Registered with under # NCT01113762.......BACKGROUND AND PURPOSE: Wear particles from metal-on-metal arthroplasties are under suspicion for adverse effects both locally and systemically, and the DePuy ASR Hip Resurfacing System (RHA) has above-average failure rates. We compared lymphocyte counts in RHA and total hip arthroplasty (THA....... RESULTS: The T-lymphocyte counts for both implant types declined over the 2-year period. This decline was statistically significant for CD3(+)CD8(+) in the THA group, with a regression coefficient of -0.04 × 10(9)cells/year (95% CI: -0.08 to -0.01). Regression analysis indicated a depressive effect...

  8. Stretch-induced Ca2+ independent ATP release in hippocampal astrocytes. (United States)

    Xiong, Yingfei; Teng, Sasa; Zheng, Lianghong; Sun, Suhua; Li, Jie; Guo, Ning; Li, Mingli; Wang, Li; Zhu, Feipeng; Wang, Changhe; Rao, Zhiren; Zhou, Zhuan


    Similar to neurons, astrocytes actively participate in synaptic transmission via releasing gliotransmitters. The Ca 2+ -dependent release of gliotransmitters includes glutamate and ATP. Following an 'on-cell-like' mechanical stimulus to a single astrocyte, Ca 2+ independent single, large, non-quantal, ATP release occurs. Astrocytic ATP release is inhibited by either selective antagonist treatment or genetic knockdown of P2X7 receptor channels. Our work suggests that ATP can be released from astrocytes via two independent pathways in hippocampal astrocytes; in addition to the known Ca 2+ -dependent vesicular release, larger non-quantal ATP release depends on P2X7 channels following mechanical stretch. Astrocytic ATP release is essential for brain functions such as synaptic long-term potentiation for learning and memory. However, whether and how ATP is released via exocytosis remains hotly debated. All previous studies of non-vesicular ATP release have used indirect assays. By contrast, two recent studies report vesicular ATP release using more direct assays. In the present study, using patch clamped 'ATP-sniffer cells', we re-investigated astrocytic ATP release at single-vesicle resolution in hippocampal astrocytes. Following an 'on-cell-like' mechanical stimulus of a single astrocyte, a Ca 2+ independent single large non-quantal ATP release occurred, in contrast to the Ca 2+ -dependent multiple small quantal ATP release in a chromaffin cell. The mechanical stimulation-induced ATP release from an astrocyte was inhibited by either exposure to a selective antagonist or genetic knockdown of P2X7 receptor channels. Functional P2X7 channels were expressed in astrocytes in hippocampal brain slices. Thus, in addition to small quantal ATP release, larger non-quantal ATP release depends on P2X7 channels in astrocytes. © 2018 The Authors. The Journal of Physiology © 2018 The Physiological Society.

  9. Role of reactive oxygen species and Bcl-2 family proteins in TNF-α-induced apoptosis of lymphocytes. (United States)

    Ryazanceva, N V; Novickiy, V V; Zhukova, O B; Biktasova, A K; Chechina, O E; Sazonova, E V; Belkina, M V; Chasovskih, N Yu; Khaitova, Z K


    We studied the in vitro apoptosis-inducing effect of recombinant TNF-α (rTNF-α) on blood lymphocytes from healthy donors. rTNF-α-induced apoptosis was accompanied by an increase in the number of cells with low mitochondrial transmembrane potential, increased intracellular content of reactive oxygen species, reduced content of Bcl-2, Bcl-xL, and Bax proteins, and elevated Bad content. The molecular mechanisms of these changes are discussed.

  10. ATP and phosphocreatine utilization in single human muscle fibres during the development of maximal power output at elevated muscle temperatures. (United States)

    Gray, Stuart R; Söderlund, Karin; Ferguson, Richard A


    In this study, we examined the effect of muscle temperature (Tm) on adenosine triphosphate (ATP) and phosphocreatine utilization in single muscle fibres during the development of maximal power output in humans. Six male participants performed a 6-s maximal sprint on a friction-braked cycle ergometer under both normal (Tm = 34.3 degrees C, s = 0.6) and elevated (T(m) = 37.3 degrees C, s = 0.2) muscle temperature conditions. During the elevated condition, muscle temperature of the legs was raised, passively, by hot water immersion followed by wrapping in electrically heated blankets. Muscle biopsies were taken from the vastus lateralis before and immediately after exercise. Freeze-dried single fibres were dissected, characterized according to myosin heavy chain composition, and analysed for ATP and phosphocreatine content. Single fibres were classified as: type I, IIA, IIAX25 (1 - 25% IIX isoform), IIAX50 (26 - 50% IIX), IIAX75 (51 - 75% IIX), or IIAX100 (76 - 100% IIX). Maximal power output and pedal rate were both greater (P < 0.05) during the elevated condition by 258 W (s = 110) and 22 rev . min(-1) (s = 6), respectively. In both conditions, phosphocreatine content decreased significantly in all fibre types, with a greater decrease during the elevated condition in type IIA fibres (P < 0.01). Adenosine triphosphate content was also reduced to a greater (P < 0.01) extent in type IIA fibres during the elevated condition. The results of the present study indicate that after passive elevation of muscle temperature, there was a greater decrease in ATP and phosphocreatine content in type IIA fibres than in the normal trial, which contributed to the higher maximal power output.

  11. The dynamic equilibrium between ATP synthesis and ATP consumption is lower in isolated mitochondria from myotubes established from type 2 diabetic subjects compared to lean control

    DEFF Research Database (Denmark)

    Minet, Ariane D; Gaster, Michael


    compared to lean control. The ATP synthesis rate without ATP consumption was not different between groups and there were no significant gender differences. The mitochondrial dysfunction in type 2 diabetes in vivo is partly based on a primarily impaired ATP synthesis....... or not in the mitochondria of diabetic skeletal muscle from subjects with type 2 diabetes. ATP synthesis was measured on mitochondria isolated from cultured myotubes established from lean (11/9), obese (9/11) and subjects with type 2 diabetes (9/11) (female/male, n=20 in each group), precultured under normophysiological...... selects the mitochondria based on an antibody recognizing the mitochondrial outer membrane and not by size through gradient centrifugation. The dynamic equilibrium between ATP synthesis and ATP consumption is 35% lower in isolated mitochondria from myotubes established from type 2 diabetic subjects...

  12. Wilson Disease Protein ATP7B Utilizes Lysosomal Exocytosis to Maintain Copper Homeostasis

    NARCIS (Netherlands)

    Polishchuk, Elena V.; Concilli, Mafalda; Iacobacci, Simona; Chesi, Giancarlo; Pastore, Nunzia; Piccolo, Pasquale; Paladino, Simona; Baldantoni, Daniela; van IJzendoorn, Sven C. D.; Chan, Jefferson; Chang, Christopher J.; Amoresano, Angela; Pane, Francesca; Pucci, Piero; Tarallo, Antonietta; Parenti, Giancarlo; Brunetti-Pierri, Nicola; Settembre, Carmine; Ballabio, Andrea; Polishchuk, Roman S.


    Copper is an essential yet toxic metal and its overload causes Wilson disease, a disorder due to mutations in copper transporter ATP7B. To remove excess copper into the bile, ATP7B traffics toward canalicular area of hepatocytes. However, the trafficking mechanisms of ATP7B remain elusive. Here, we

  13. Stimulation of acetoin production in metabolically engineered Lactococcus lactis by increasing ATP demand

    DEFF Research Database (Denmark)

    Liu, Jianming; Kandasamy, Vijayalakshmi; Würtz, Anders


    Having a sufficient supply of energy, usually in the form of ATP, is essential for all living organisms. In this study, however, we demonstrate that it can be beneficial to reduce ATP availability when the objective is microbial production. By introducing the ATP hydrolyzing F1-ATPase into a Lact...

  14. A comparative study of ATPase subunit 9 (Atp9) gene between ...

    African Journals Online (AJOL)

    ATPase subunit 9 gene (Atp9) is an important functional gene in mitochondria, and is closely related with energy supply. RNA editing of atp9 gene was associated with male sterility in plants. In this study, the atp9 gene in soybeans was cloned from a soybean cytoplasmic male sterile line NJCMS2A and its maintainer line ...

  15. Statistical Mechanics Analysis of ATP Binding to a Multisubunit Enzyme

    International Nuclear Information System (INIS)

    Zhang Yun-Xin


    Due to inter-subunit communication, multisubunit enzymes usually hydrolyze ATP in a concerted fashion. However, so far the principle of this process remains poorly understood. In this study, from the viewpoint of statistical mechanics, a simple model is presented. In this model, we assume that the binding of ATP will change the potential of the corresponding enzyme subunit, and the degree of this change depends on the state of its adjacent subunits. The probability of enzyme in a given state satisfies the Boltzmann's distribution. Although it looks much simple, this model can fit the recent experimental data of chaperonin TRiC/CCT well. From this model, the dominant state of TRiC/CCT can be obtained. This study provide a new way to understand biophysical processe by statistical mechanics analysis. (interdisciplinary physics and related areas of science and technology)

  16. Structure and mechanism of ATP-dependent phospholipid transporters

    DEFF Research Database (Denmark)

    Lopez Marques, Rosa Laura; Poulsen, Lisbeth Rosager; Bailly, Aurélien


    Background ATP-binding cassette (ABC) transporters and P4-ATPases are two large and seemingly unrelated families of primary active pumps involved in moving phospholipids from one leaflet of a biological membrane to the other. Scope of review This review aims to identify common mechanistic features...... in the way phospholipid flipping is carried out by two evolutionarily unrelated families of transporters. Major conclusions Both protein families hydrolyze ATP, although they employ different mechanisms to use it, and have a comparable size with twelve transmembrane segments in the functional unit. Further......, despite differences in overall architecture, both appear to operate by an alternating access mechanism and during transport they might allow access of phospholipids to the internal part of the transmembrane domain. The latter feature is obvious for ABC transporters, but phospholipids and other hydrophobic...

  17. Chronic lymphocytic leukemia: concepts and observations

    Energy Technology Data Exchange (ETDEWEB)

    Chandra, P.; Chanana, A.D.; Chikkappa, G.; Cronkite, E.P.


    Thirty-five patients with chronic lymphocytic leukemia (CLL) were studied for assessment of total body leukemic mass and abnormality in T-lymphocyte function associated with clinical stages of CLL. Total body potassium (TBK), an indicator of lean body mass, was found to correlate well with increase in the clinical stage of the disease. Use of TBK for monitoring the regression and relapse of leukemic load is suggested. No correlation was found between whole cell and nuclear volumes of lymphocytes in CLL patients and clinical stages of the disease. Blast transformation and proliferation under phytohemagglutinin (PHA) stimulation appeared to be normal in purified T cells of early stages and abnormal in the late stages of disease.

  18. Cellular energy metabolism in T-lymphocytes. (United States)

    Gaber, Timo; Strehl, Cindy; Sawitzki, Birgit; Hoff, Paula; Buttgereit, Frank


    Energy homeostasis is a hallmark of cell survival and maintenance of cell function. Here we focus on the impact of cellular energy metabolism on T-lymphocyte differentiation, activation, and function in health and disease. We describe the role of transcriptional and posttranscriptional regulation of lymphocyte metabolism on immune functions of T cells. We also summarize the current knowledge about T-lymphocyte adaptations to inflammation and hypoxia, and the impact on T-cell behavior of pathophysiological hypoxia (as found in tumor tissue, chronically inflamed joints in rheumatoid arthritis and during bone regeneration). A better understanding of the underlying mechanisms that control immune cell metabolism and immune response may provide therapeutic opportunities to alter the immune response under conditions of either immunosuppression or inflammation, potentially targeting infections, vaccine response, tumor surveillance, autoimmunity, and inflammatory disorders.

  19. Ballast water compliance monitoring: A new application for ATP (United States)

    Lo Curto, A.; Stehouwer, P.; Gianoli, C.; Schneider, G.; Raymond, M.; Bonamin, V.


    The coming into force of the USCG ballast water regulations and the IMO ballast water management convention resulted in the development of several technologies approved for the treatment of ballast water. To ensure compliance of these technologies, the development of rapid and robust analysis methods was necessary. In collaboration with the SGS Group (Switzerland) and LuminUltra (Canada), Aqua-tools (France) has developed an innovative Ballast Water Treatment Monitoring (BWTM) kit for rapid onboard testing. The affordable kit provides results in less than 1 h, is easy to use and durable ensuring that the ballast water treatment system on the ship is fully compliant with the discharge standards upon arrival in port. The core of this method is a combination of high-quality reagents (lysis solution and ATP 2G Luminase™ enzyme) not inhibited by salinity and a patented fast homogenizing method for ATP extraction developed for a higher ATP recovery from zooplankton and phytoplankton. Compared to traditional analysis methods, the BWTM Kit provides fast and accurate results for all three fractions of microorganisms (≥ 50 μm, ≥ 10 ÷ < 50 μm and bacteria). Preliminary tests carried out in cooperation with SGS showed that the proposed method was able to detect onboard the efficiency of the treatment systems used. Compliance limits were established for all size fractions and a correlation between the standard methods (microscopy, plate count, MPN) and ATP was evaluated. The BWTM kit can provide a fast indication of compliance or gross exceedance. The rare borderline cases, when encountered, of course require additional confirmation.

  20. The thermodynamic efficiency of ATP synthesis in oxidative phosphorylation. (United States)

    Nath, Sunil


    As the chief energy source of eukaryotic cells, it is important to determine the thermodynamic efficiency of ATP synthesis in oxidative phosphorylation (OX PHOS). Previous estimates of the thermodynamic efficiency of this vital process have ranged from Lehninger's original back-of-the-envelope calculation of 38% to the often quoted value of 55-60% in current textbooks of biochemistry, to high values of 90% from recent information theoretic considerations, and reports of realizations of close to ideal 100% efficiencies by single molecule experiments. Hence this problem has been reinvestigated from first principles. The overall thermodynamic efficiency of ATP synthesis in the mitochondrial energy transduction OX PHOS process has been found to lie between 40 and 41% from four different approaches based on a) estimation using structural and biochemical data, b) fundamental nonequilibrium thermodynamic analysis, c) novel insights arising from Nath's torsional mechanism of energy transduction and ATP synthesis, and d) the overall balance of cellular energetics. The torsional mechanism also offers an explanation for the observation of a thermodynamic efficiency approaching 100% in some experiments. Applications of the unique, molecular machine mode of functioning of F 1 F O -ATP synthase involving direct inter-conversion of chemical and mechanical energies in the design and fabrication of novel, man-made mechanochemical devices have been envisaged, and some new ways to exorcise Maxwell's demon have been proposed. It is hoped that analysis of the fundamental problem of energy transduction in OX PHOS from a fresh perspective will catalyze new avenues of research in this interdisciplinary field. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Alternative mitochondrial functions in cell physiopathology: beyond ATP production

    Directory of Open Access Journals (Sweden)

    Kowaltowski A.J.


    Full Text Available It is well known that mitochondria are the main site for ATP generation within most tissues. However, mitochondria also participate in a surprising number of alternative activities, including intracellular Ca2+ regulation, thermogenesis and the control of apoptosis. In addition, mitochondria are the main cellular generators of reactive oxygen species, and may trigger necrotic cell death under conditions of oxidative stress. This review concentrates on these alternative mitochondrial functions, and their role in cell physiopathology.

  2. Catalytic strategy used by the myosin motor to hydrolyze ATP. (United States)

    Kiani, Farooq Ahmad; Fischer, Stefan


    Myosin is a molecular motor responsible for biological motions such as muscle contraction and intracellular cargo transport, for which it hydrolyzes adenosine 5'-triphosphate (ATP). Early steps of the mechanism by which myosin catalyzes ATP hydrolysis have been investigated, but still missing are the structure of the final ADP·inorganic phosphate (Pi) product and the complete pathway leading to it. Here, a comprehensive description of the catalytic strategy of myosin is formulated, based on combined quantum-classical molecular mechanics calculations. A full exploration of catalytic pathways was performed and a final product structure was found that is consistent with all experiments. Molecular movies of the relevant pathways show the different reorganizations of the H-bond network that lead to the final product, whose γ-phosphate is not in the previously reported HPγO4(2-) state, but in the H2PγO4(-) state. The simulations reveal that the catalytic strategy of myosin employs a three-pronged tactic: (i) Stabilization of the γ-phosphate of ATP in a dissociated metaphosphate (PγO3(-)) state. (ii) Polarization of the attacking water molecule, to abstract a proton from that water. (iii) Formation of multiple proton wires in the active site, for efficient transfer of the abstracted proton to various product precursors. The specific role played in this strategy by each of the three loops enclosing ATP is identified unambiguously. It explains how the precise timing of the ATPase activation during the force generating cycle is achieved in myosin. The catalytic strategy described here for myosin is likely to be very similar in most nucleotide hydrolyzing enzymes.

  3. [The Influence of UV-Light on the Sub-Populational Composition and Expression of Membrane Markers of Lymphocytes of Donor Blood]. (United States)

    Artyukhov, V G; Basharina, O V; Zemchenkova, O V; Ryazantsev, S V


    The influence of UV-light (240-390 nm) at dozes of 151 and 755 J/m2 on the content of membrane markers of lymphocytes using the method of flow cytometry was investigated. It was demonstrated that during incubation of UV-irradiated lymphocytes the change of their populational and sub-populational composition occurs. Expression of complexes of CD3, CD 19,.CD8, CD 16, CD25 and CD95 increased. This increase was caused mainly by de novo synthesis. UV-light had immunostimulating effect on CD8+ T-lymphocyte population. Together with the increase of cytotoxic cells and NK-cells, activation of lymphocytes (increased amount of CD25+ and CD95+ cells) took place. Amount of cells undergone apoptosis or necrosis increased proportionally to the dosage. These changes were more expressed during incubation of lymphocytes in nutrition medium without autological blood serum, e.g. under deficiency of growth factors and antioxidants.

  4. AMP-activated protein kinase regulates lymphocyte responses to metabolic stress but is largely dispensable for immune cell development and function. (United States)

    Mayer, Alice; Denanglaire, Sébastien; Viollet, Benoit; Leo, Oberdan; Andris, Fabienne


    AMP-activated protein kinase (AMPK), a phylogenetically conserved serine/threonine protein kinase, represents an energy sensor able to adapt cellular metabolism in response to nutritional environmental variations. TCR stimulation activates AMPK, a regulatory event that is known to stimulate ATP-producing processes, possibly in anticipation of the increased energetic needs associated with cell division and expression of effector function. Taking advantage of the selective expression of the AMPKalpha1 catalytic subunit in lymphoid cells, we have analyzed the in vitro and in vivo capacity of lymphocytes lacking AMPK activity (AMPKalpha1-KO cells) to respond to metabolic stress and to initiate and sustain an immune response. AMPKalpha1-KO cells displayed increasing sensitivity to energetic stress in vitro, and were found unable to maintain adequate ATP levels in response to ATP synthase inhibition. These cells were, however, able to respond to antigen stimulation in vitro, as shown by optimal proliferation and cytokine production. Similarly, AMPKalpha1-KO mice were fully immunocompetent in vivo and displayed normal cell proliferation, humoral, cytotoxic and delayed-type hypersensitivity (DTH) responses following antigen injection. In conclusion, AMPK represents an important enzyme allowing lymphocytes to resist a mild energy crisis in vitro, but is largely dispensable for activation and expression of effector function in response to antigen stimulation.

  5. Persister formation in Staphylococcus aureus is associated with ATP depletion

    Energy Technology Data Exchange (ETDEWEB)

    Conlon, Brian P.; Rowe, Sarah E.; Gandt, Autumn Brown; Nuxoll, Austin S.; Donegan, Niles P.; Zalis, Eliza A.; Clair, Geremy; Adkins, Joshua N.; Cheung, Ambrose L.; Lewis, Kim


    Persisters are dormant phenotypic variants of bacterial cells that are tolerant to killing by antibiotics1. Persisters are associated with chronic bacterial infection and antibiotic treatment failure. In Escherichia coli, toxin/antitoxin (TA) modules are responsible for persister formation. The mechanism of persister formation in Gram positive bacteria is unknown. Staphylococcus aureus is a major human pathogen, responsible for a variety of chronic and relapsing infections such as osteomyelitis, endocarditis and infections of implanted devices. Deleting TA modules in S. aureus did not affect the level of persisters. Here we show that S. aureus persisters are produced due to a stochastic entrance to stationary phase accompanied by a drop in intracellular ATP. Cells expressing stationary state markers are present throughout the growth phase, increasing in frequency with cell density. Cell sorting revealed that expression of stationary markers was associated with a 100-1000 fold increased likelihood of survival to antibiotic challenge. We find that the antibiotic tolerance of these cells is due to a drop in intracellular ATP. The ATP level of the cell is predictive of bactericidal antibiotic efficacy and explains bacterial tolerance to antibiotic treatment.

  6. Imidazopyridine Compounds Inhibit Mycobacterial Growth by Depleting ATP Levels. (United States)

    O'Malley, Theresa; Alling, Torey; Early, Julie V; Wescott, Heather A; Kumar, Anuradha; Moraski, Garrett C; Miller, Marvin J; Masquelin, Thierry; Hipskind, Philip A; Parish, Tanya


    The imidazopyridines are a promising new class of antitubercular agents with potent activity in vitro and in vivo We isolated mutants of Mycobacterium tuberculosis resistant to a representative imidazopyridine; the mutants had large shifts (>20-fold) in MIC. Whole-genome sequencing revealed mutations in Rv1339, a hypothetical protein of unknown function. We isolated mutants resistant to three further compounds from the series; resistant mutants isolated from two of the compounds had single nucleotide polymorphisms in Rv1339 and resistant mutants isolated from the third compound had single nucleotide polymorphisms in QcrB, the proposed target for the series. All the strains were resistant to two compounds, regardless of the mutation, and a strain carrying the QcrB T313I mutation was resistant to all of the imidazopyridine derivatives tested, confirming cross-resistance. By monitoring pH homeostasis and ATP generation, we confirmed that compounds from the series were targeting QcrB; imidazopyridines disrupted pH homeostasis and depleted ATP, providing further evidence of an effect on the electron transport chain. A representative compound was bacteriostatic against replicating bacteria, consistent with a mode of action against QcrB. The series had a narrow inhibitory spectrum, with no activity against other bacterial species. No synergy or antagonism was seen with other antituberculosis drugs under development. In conclusion, our data support the hypothesis that the imidazopyridine series functions by reducing ATP generation via inhibition of QcrB. Copyright © 2018 O'Malley et al.

  7. Effect of ATP sulfurylase overexpression in bright yellow 2 tobacco cells: regulation of ATP sulfurylase and SO4(-2) transport activities

    International Nuclear Information System (INIS)

    Hatzfeld, Y.; Cathala, N.; Grignon, C.; Davidian, J.C.


    To determine if the ATP sulfurylase reaction is a regulatory step for the SO4(2-)-assimilation pathway in plants, an Arabidopsis thaliana ATP sulfurylase cDNA, APS2, was fused to the 355 promoter of the cauliflower mosaic virus and introduced by Agrobacterium tumefaciens-mediated transformation into isolated Bright Yellow 2 tobacco (Nicotiana tabacum) cells. The ATP sulfurylase activity in transgenic cells was 8-fold that in control cells, and was correlated with the expression of a specific polypeptide revealed by western analysis using an anti-ATP sulfurylase antibody. The molecular mass of this polypeptide agreed with that for the overexpressed mature protein. ATP sulfurylase overexpression had no effect on [35S]SO4(2-) influx or ATP sulfurylase activity regulation by S availability, except that ATP sulfurylase activity variations in response to S starvation in transgenic cells were 8 times higher than in the wild type. There were also no differences in cell growth or sensitivity to SeO4(2-) (a toxic SO4(2-) analog) between transgenic and wild-type cells. We propose that in Bright Yellow 2 tobacco cells, the ATP sulfurylase derepression by S deficiency may involve a posttranscriptional mechanism, and that the ATP sulfurylase abundance is not limiting for cell metabolism

  8. Insulin induces a positive relationship between the rates of ATP and glycogen changes in isolated rat liver in presence of glucose; a 31P and 13C NMR study

    Directory of Open Access Journals (Sweden)

    Gin Henri


    Full Text Available Abstract Background There is an emerging theory suggesting that insulin, which is known to be the predominant postprandial anabolic hormone, is also a major regulator of mitochondrial oxidative phosphorylation in human skeletal muscle. However, little is known about its effects in the liver. Since there is a theoretical relationship between glycogen metabolism and energy status, a simultaneous and continuous investigation of hepatic ATP and glycogen content was performed in intact and isolated perfused liver by 31P and 13C nuclear magnetic resonance (NMR The hepatic rates of ATP and glycogen changes were evaluated with different concentrations of insulin and glucose during continuous and short-term supply. Results Liver from rats fed ad libitum were perfused with Krebs-Henseleit Buffer (KHB(controls or KHB containing 6 mM glucose, 30 mM glucose, insulin alone, insulin + 6 mM glucose, insulin + 30 mM glucose. In the control, glycogenolysis occurred at a rate of -0.53 ± 0.021 %·min-1 and ATP content decreased at a rate of -0.28 ± 0.029 %·min-1. In the absence of insulin, there was a close proportional relationship between the glycogen flux and the glucose concentration, whereas ATP rates never varied. With insulin + glucose, both glycogen and ATP rates were strongly related to the glucose concentration; the magnitude of net glycogen flux was linearly correlated to the magnitude of net ATP flux: fluxglycogen = 72.543(fluxATP + 172.08, R2 = 0.98. Conclusion Only the co-infusion of 30 mM glucose and insulin led to (i a net glycogen synthesis, (ii the maintenance of the hepatic ATP content, and a strong positive correlation between their net fluxes. This has never previously been reported. The specific effect of insulin on ATP change is likely related to a rapid stimulation of the hepatic mitochondrial oxidative phosphorylation. We propose that variations in the correlation between rates of ATP and glycogen changes could be a probe for insulin

  9. Insulin induces a positive relationship between the rates of ATP and glycogen changes in isolated rat liver in presence of glucose; a 31P and 13C NMR study. (United States)

    Baillet-Blanco, Laurence; Beauvieux, Marie-Christine; Gin, Henri; Rigalleau, Vincent; Gallis, Jean-Louis


    There is an emerging theory suggesting that insulin, which is known to be the predominant postprandial anabolic hormone, is also a major regulator of mitochondrial oxidative phosphorylation in human skeletal muscle. However, little is known about its effects in the liver. Since there is a theoretical relationship between glycogen metabolism and energy status, a simultaneous and continuous investigation of hepatic ATP and glycogen content was performed in intact and isolated perfused liver by 31P and 13C nuclear magnetic resonance (NMR) The hepatic rates of ATP and glycogen changes were evaluated with different concentrations of insulin and glucose during continuous and short-term supply. Liver from rats fed ad libitum were perfused with Krebs-Henseleit Buffer (KHB)(controls) or KHB containing 6 mM glucose, 30 mM glucose, insulin alone, insulin + 6 mM glucose, insulin + 30 mM glucose. In the control, glycogenolysis occurred at a rate of -0.53 +/- 0.021 % x min(-1) and ATP content decreased at a rate of -0.28 +/- 0.029 % x min(-1). In the absence of insulin, there was a close proportional relationship between the glycogen flux and the glucose concentration, whereas ATP rates never varied. With insulin + glucose, both glycogen and ATP rates were strongly related to the glucose concentration; the magnitude of net glycogen flux was linearly correlated to the magnitude of net ATP flux: flux(glycogen) = 72.543(fluxATP) + 172.08, R2 = 0.98. Only the co-infusion of 30 mM glucose and insulin led to (i) a net glycogen synthesis, (ii) the maintenance of the hepatic ATP content, and a strong positive correlation between their net fluxes. This has never previously been reported. The specific effect of insulin on ATP change is likely related to a rapid stimulation of the hepatic mitochondrial oxidative phosphorylation. We propose that variations in the correlation between rates of ATP and glycogen changes could be a probe for insulin resistance due to the action of substrates

  10. Lymphocytic hypophysitis: occurrence in two men. (United States)

    Lee, J H; Laws, E R; Guthrie, B L; Dina, T S; Nochomovitz, L E


    Two men undergoing transsphenoidal exploration for pituitary adenoma were found to have lymphocytic hypophysitis. Both presented with frontal headaches, lethargy, and diminished libido. Laboratory investigations showed markedly depressed serum testosterone, and magnetic resonance imaging demonstrated pituitary enlargement, with optic chiasm involvement. Intraoperatively, the dura was adherent to the pituitary in each case. The resected glands were effaced by a dense lymphoplasmacytic infiltrate and fibrosis, without granulomas. Nonspecific peripheral enhancement on imaging suggested a diagnosis other than adenoma, but more experience with peripheral enhancement in lymphocytic hypophysitis is needed. The diagnosis was histological and required surgical intervention. Long-term pituitary replacement therapy is usually required.

  11. Primary lymphocytic lymphoma of lacrimal gland. (United States)

    Romero-Caballero, M D; Lozano-García, I; Gómez-Molina, C; Gil-Liñán, A I; Arcas, I


    We report a case of primary small-cell lymphocytic lacrimal gland lymphoma in a male diagnosed with primary antiphospholipid syndrome. These rare lymphomas are usually presented in the clinic as disseminations secondary to chronic lymphocytic leukaemia, and the primary site is rare in the orbit. Non-Hodgkin lymphomas are a heterogeneous group of tumours. Although treatment in the IE stage is usually radiotherapy, due to its association with antiphospholipid syndrome, systemic treatment with rituximab was administered. Copyright © 2016 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

  12. Malnutrition-associated liver steatosis and ATP depletion is caused by peroxisomal and mitochondrial dysfunction. (United States)

    van Zutphen, Tim; Ciapaite, Jolita; Bloks, Vincent W; Ackereley, Cameron; Gerding, Albert; Jurdzinski, Angelika; de Moraes, Roberta Allgayer; Zhang, Ling; Wolters, Justina C; Bischoff, Rainer; Wanders, Ronald J; Houten, Sander M; Bronte-Tinkew, Dana; Shatseva, Tatiana; Lewis, Gary F; Groen, Albert K; Reijngoud, Dirk-Jan; Bakker, Barbara M; Jonker, Johan W; Kim, Peter K; Bandsma, Robert H J


    Severe malnutrition in young children is associated with signs of hepatic dysfunction such as steatosis and hypoalbuminemia, but its etiology is unknown. Peroxisomes and mitochondria play key roles in various hepatic metabolic functions including lipid metabolism and energy production. To investigate the involvement of these organelles in the mechanisms underlying malnutrition-induced hepatic dysfunction we developed a rat model of malnutrition. Weanling rats were placed on a low protein or control diet (5% or 20% of calories from protein, respectively) for four weeks. Peroxisomal and mitochondrial structural features were characterized using immunofluorescence and electron microscopy. Mitochondrial function was assessed using high-resolution respirometry. A novel targeted quantitative proteomics method was applied to analyze 47 mitochondrial proteins involved in oxidative phosphorylation, tricarboxylic acid cycle and fatty acid β-oxidation pathways. Low protein diet-fed rats developed hypoalbuminemia and hepatic steatosis, consistent with the human phenotype. Hepatic peroxisome content was decreased and metabolomic analysis indicated peroxisomal dysfunction. This was followed by changes in mitochondrial ultrastructure and increased mitochondrial content. Mitochondrial function was impaired due to multiple defects affecting respiratory chain complex I and IV, pyruvate uptake and several β-oxidation enzymes, leading to strongly reduced hepatic ATP levels. Fenofibrate supplementation restored hepatic peroxisome abundance and increased mitochondrial β-oxidation capacity, resulting in reduced steatosis and normalization of ATP and plasma albumin levels. Malnutrition leads to severe impairments in hepatic peroxisomal and mitochondrial function, and hepatic metabolic dysfunction. We discuss the potential future implications of our findings for the clinical management of malnourished children. Severe malnutrition in children is associated with metabolic disturbances

  13. Ins(1,4,5)P{sub 3} facilitates ATP accumulation via phosphocreatine/creatine kinase in the endoplasmic reticulum extracted from MDCK cells

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Jing [Medical Research Center, School of Medicine, Fukuoka University, Fukuoka 814-0180 (Japan); Department of Dental Implantology, School of Stomatology, Tongji University, Shanghai 200072 (China); Ogata, Shigenori [Joint Laboratory for Frontier Medical Science, School of Medicine, Fukuoka University, Fukuoka 814-0180 (Japan); Segawa, Masaru [Central Laboratory for Pathology and Morphology, School of Medicine, Fukuoka University, Fukuoka 814-0180 (Japan); Usune, Sadaharu [Research Laboratory of Biodynamics, School of Medicine, Fukuoka University, Fukuoka 814-0180 (Japan); Zhao, Yumei [Department of Pediatric Dentistry, School of Dentistry of Shanghai Tongji University, Shanghai 200072 (China); Katsuragi, Takeshi, E-mail: [Medical Research Center, School of Medicine, Fukuoka University, Fukuoka 814-0180 (Japan)


    So far, the content and accumulation of ATP in isolated endoplasmic reticulum (ER) are little understood. First, we confirmed using electron microscopic and Western blotting techniques that the samples extracted from MDCK cells are endoplasmic reticulum (ER). The amounts of ATP in the extracted ER were measured from the filtrate after a spinning down of ultrafiltration spin column packed with ER. When the ER sample (5 {mu}g) after 3 days freezing was suspended in intracellular medium (ICM), 0.1% Triton X and ultrapure water (UPW), ATP amounts from the ER with UPW were the highest and over 10 times compared with that from the control with ICM, indicating that UPW is the most effective tool in destroying the ER membrane. After a 10-min-incubation with ICM containing phosphocreatine (PCr)/creatine kinase (CK) of the fresh ER. ATP amounts in the filtrate obtained by spinning down were not changed from that in the control (no PCr/CK). However, ATP amounts in the filtrate from the second spinning down of the ER (treated with PCr/CK) suspended in UPW became over 10-fold compared with the control. When 1 {mu}M inositol(1,4,5)trisphosphate (Ins(1,4,5)P{sub 3}) was added in the incubation medium (ICM with PCr/CK), ATP amounts from the filtrate after the second spinning down were further enhanced around three times. This enhancement was almost canceled by Ca{sup 2+}-removal from ICM and by adding thapsigargin, a Ca{sup 2+}-ATPase inhibitor, but not by 2-APB and heparin, Ins(1,4,5)P{sub 3} receptor antagonists. Administration of 500 {mu}M adenosine to the incubation medium (with PCr/CK) failed to enhance the accumulation of ATP in the ER. These findings suggest that the ER originally contains ATP and ATP accumulation in the ER is promoted by PCr/CK and Ins(1,4,5)P{sub 3}.

  14. Label free luminescence strategy for sensitive detection of ATP using aptamer-Ru(II) complexes

    Energy Technology Data Exchange (ETDEWEB)

    Babu, Eththilu [Department of Physical Che mistry, School of Chemistry, Madurai Kamaraj University, Madurai 625021, Tamil Nadu (India); Muthu Mareeswaran, Paulpandian [Department of Physical Che mistry, School of Chemistry, Madurai Kamaraj University, Madurai 625021, Tamil Nadu (India); Department of Industrial Chemistry, Alagappa Univesity, Karaikudi 630003, Tamil Nadu (India); Ramdass, Arumugam [Department of Physical Che mistry, School of Chemistry, Madurai Kamaraj University, Madurai 625021, Tamil Nadu (India); Research Department of Chemistry, Aditanar College of Arts and Science, Tiruchendur 628216, Tamil Nadu (India); Ramesh, Pandian [UCIBIO-REQUIMTE, Departmento de Química, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2829-516 Caparica (Portugal); Rajagopal, Seenivasan, E-mail: [Department of Physical Che mistry, School of Chemistry, Madurai Kamaraj University, Madurai 625021, Tamil Nadu (India)


    A simple and sensitive aptamer-based luminescence strategy for ATP detection is developed using Ru(II) complexes as probe molecule. It is based on the fact that Ru(II)-dppz complexes show the light switching behavior with DNA aptamers and found to show significant luminescence spectral change on the addition of ATP molecules. The binding efficiencies of aptamer with ATP, ADP and AMP are calculated and compared. The structural change of aptamer is also studied using circular dichroism (CD) spectral techniques. Moreover, the binding nature of aptamer with ATP, ADP and AMP is demonstrated by computational techniques. The proposed strategy was successfully applied to the detection of ATP.

  15. Label free luminescence strategy for sensitive detection of ATP using aptamer-Ru(II) complexes

    International Nuclear Information System (INIS)

    Babu, Eththilu; Muthu Mareeswaran, Paulpandian; Ramdass, Arumugam; Ramesh, Pandian; Rajagopal, Seenivasan


    A simple and sensitive aptamer-based luminescence strategy for ATP detection is developed using Ru(II) complexes as probe molecule. It is based on the fact that Ru(II)-dppz complexes show the light switching behavior with DNA aptamers and found to show significant luminescence spectral change on the addition of ATP molecules. The binding efficiencies of aptamer with ATP, ADP and AMP are calculated and compared. The structural change of aptamer is also studied using circular dichroism (CD) spectral techniques. Moreover, the binding nature of aptamer with ATP, ADP and AMP is demonstrated by computational techniques. The proposed strategy was successfully applied to the detection of ATP.

  16. Extracellular ATP4- promotes cation fluxes in the J774 mouse macrophage cell line

    International Nuclear Information System (INIS)

    Steinberg, T.H.; Silverstein, S.C.


    Extracellular ATP stimulates transmembrane ion fluxes in the mouse macrophage cell line J774. In the presence of Mg2+, nonhydrolyzable ATP analogs and other purine and pyrimidine nucleotides do not elicit this response, suggesting the presence of a specific receptor for ATP on the macrophage plasma membrane. One candidate for such a receptor is the ecto-ATPase expressed on these cells. We, therefore, investigated the role of this enzyme in ATP-induced 86 Rb+ efflux in J774 cells. The ecto-ATPase had a broad nucleotide specificity and did not hydrolyze extracellular ATP in the absence of divalent cations. 86 Rb+ efflux was not blocked by inhibition of the ecto-ATPase and did not require Ca2+ or Mg2+. In fact, ATP-stimulated 86 Rb+ efflux was inhibited by Mg2+ and correlated with the availability of ATP4- in the medium. In the absence of divalent cations, the slowly hydrolyzable ATP analogs adenosine 5'-(beta, gamma-imido)triphosphate (AMP-PNP) and adenosine 5'-O-(3-thio)triphosphate (ATP-gamma-S) also stimulated 86 Rb+ efflux, albeit at higher concentrations than that required for ATP4-. Exposure of J774 cells to 10 mM ATP for 45 min caused death of 95% of cells. By this means we selected variant J774 cells that did not exhibit 86 Rb+ efflux in the presence of extracellular ATP but retained ecto-ATPase activity. These results show that the ecto-ATPase of J774 cells does not mediate the effects of ATP on these cells; that ATP4- and not MgATP2- promotes 86 Rb+ efflux from these cells; and that hydrolysis of ATP is not required to effect this change in membrane permeability. These findings suggest that J774 cells possess a plasma membrane receptor which binds ATP4-, AMP-PNP, and ATP-gamma-S, and that the ecto-ATPase limits the effects of ATP on these cells by hydrolyzing Mg-ATP2-

  17. Small amounts of functional ATP7A protein permit mild phenotype

    DEFF Research Database (Denmark)

    Møller, Lisbeth Birk


    concentrations, ATP7A shifts to the post-Golgi compartments or to the plasma membrane to export copper out of the cell. Impaired copper-regulation trafficking has been observed for ATP7A mutants, but its impact on the clinical outcome is not clear. The major problem in patients with MD seems to be insufficient...... of missense mutations on structural models of the ATP7A protein suggests that affected conserved residues generally lead to a severe phenotype. The ATP7A protein traffics within the cells. At low copper levels, ATP7A locates to the Trans-Golgi Network (TGN) to load cuproenzymes with copper, whereas at higher...

  18. De novo mutations in ATP1A3 cause alternating hemiplegia of childhood

    DEFF Research Database (Denmark)

    Heinzen, Erin L; Swoboda, Kathryn J; Hitomi, Yuki


    and their unaffected parents to identify de novo nonsynonymous mutations in ATP1A3 in all seven individuals. In a subsequent sequence analysis of ATP1A3 in 98 other patients with AHC, we found that ATP1A3 mutations were likely to be responsible for at least 74% of the cases; we also identified one inherited mutation...... affecting the level of protein expression. This work identifies de novo ATP1A3 mutations as the primary cause of AHC and offers insight into disease pathophysiology by expanding the spectrum of phenotypes associated with mutations in ATP1A3....

  19. atpE gene as a new useful specific molecular target to quantify Mycobacterium in environmental samples (United States)


    Background The environment is the likely source of many pathogenic mycobacterial species but detection of mycobacteria by bacteriological tools is generally difficult and time-consuming. Consequently, several molecular targets based on the sequences of housekeeping genes, non-functional RNA and structural ribosomal RNAs have been proposed for the detection and identification of mycobacteria in clinical or environmental samples. While certain of these targets were proposed as specific for this genus, most are prone to false positive results in complex environmental samples that include related, but distinct, bacterial genera. Nowadays the increased number of sequenced genomes and the availability of software for genomic comparison provide tools to develop novel, mycobacteria-specific targets, and the associated molecular probes and primers. Consequently, we conducted an in silico search for proteins exclusive to Mycobacterium spp. genomes in order to design sensitive and specific molecular targets. Results Among the 3989 predicted proteins from M. tuberculosis H37Rv, only 11 proteins showed 80% to 100% of similarity with Mycobacterium spp. genomes, and less than 50% of similarity with genomes of closely related Corynebacterium, Nocardia and Rhodococcus genera. Based on DNA sequence alignments, we designed primer pairs and a probe that specifically detect the atpE gene of mycobacteria, as verified by quantitative real-time PCR on a collection of mycobacteria and non-mycobacterial species. The real-time PCR method we developed was successfully used to detect mycobacteria in tap water and lake samples. Conclusions The results indicate that this real-time PCR method targeting the atpE gene can serve for highly specific detection and precise quantification of Mycobacterium spp. in environmental samples. PMID:24299240

  20. Testis-specific isoform of Na/K-ATPase (ATP1A4) regulates sperm function and fertility in dairy bulls through potential mechanisms involving reactive oxygen species, calcium and actin polymerization. (United States)

    Rajamanickam, G D; Kroetsch, T; Kastelic, J P; Thundathil, J C


    Traditional bull breeding soundness evaluation (BBSE) eliminates bulls that are grossly abnormal; however, bulls classified as satisfactory potential breeders still vary in field fertility, implying submicroscopic differences in sperm characteristics. The testis-specific isoform of Na/K-ATPase (ATP1A4) is involved in regulation of sperm motility and capacitation in bulls through well-established enzyme activity and signaling functions. The objective was to determine ATP1A4 content, activity and their relationship to post-thaw sperm function and field fertility, using semen samples from low-fertility (LF) and high-fertility (HF) Holstein bulls (n = 20 each) with known FERTSOL rates (measure of field fertility, based on non-return rate). Frozen-thawed sperm from HF bulls had increased ATP1A4 content and activity compared to LF bulls. Furthermore, post-thaw sperm from HF bulls had increased tyrosine phosphorylation, ROS, F-actin content, and low intracellular calcium compared to LF bulls. Subsequent incubation of HF bull sperm with ouabain (a specific ligand of Na/K-ATPase) further augmented the post-thaw increase in tyrosine phosphorylation, ROS production, and F-actin content, whereas the increase in intracellular calcium was still low compared to LF bull sperm. ATP1A4 content and activity, ROS, F-actin and calcium were significantly correlated with fertility. In conclusion, we inferred that ATP1A4 content and activity differed among dairy bulls with satisfactory semen characteristics and that ATP1A4 may regulate sperm function through mechanisms involving ROS, F-actin and calcium in frozen-thawed sperm of HF and LF dairy bulls. © 2017 American Society of Andrology and European Academy of Andrology.

  1. Caffeic acid treatment alters the extracellular adenine nucleotide hydrolysis in platelets and lymphocytes of adult rats. (United States)

    Anwar, Javed; Spanevello, Roselia Maria; Pimentel, Victor Camera; Gutierres, Jessié; Thomé, Gustavo; Cardoso, Andreia; Zanini, Daniela; Martins, Caroline; Palma, Heloisa Einloft; Bagatini, Margarete Dulce; Baldissarelli, Jucimara; Schmatz, Roberta; Leal, Cláudio Alberto Martins; da Costa, Pauline; Morsch, Vera Maria; Schetinger, Maria Rosa Chitolina


    This study evaluated the effects of caffeic acid on ectonucleotidase activities such as NTPDase (nucleoside triphosphate diphosphohydrolase), Ecto-NPP (nucleotide pyrophosphatase/phosphodiesterase), 5'-nucleotidase and adenosine deaminase (ADA) in platelets and lymphocytes of rats, as well as in the profile of platelet aggregation. Animals were divided into five groups: I (control); II (oil); III (caffeic acid 10 mg/kg); IV (caffeic acid 50 mg/kg); and V (caffeic acid 100 mg/kg). Animals were treated with caffeic acid diluted in oil for 30 days. In platelets, caffeic acid decreased the ATP hydrolysis and increased ADP hydrolysis in groups III, IV and V when compared to control (P<0.05). The 5'-nucleotidase activity was decreased, while E-NPP and ADA activities were increased in platelets of rats of groups III, IV and V (P<0.05). Caffeic acid reduced significantly the platelet aggregation in the animals of groups III, IV and V in relation to group I (P<0.05). In lymphocytes, the NTPDase and ADA activities were increased in all groups treated with caffeic acid when compared to control (P<0.05). These findings demonstrated that the enzymes were altered in tissues by caffeic acid and this compound decreased the platelet aggregation suggesting that caffeic acid should be considered a potentially therapeutic agent in disorders related to the purinergic system. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Effect of hydrogen peroxide on the main kinetic parameters of ATP hydrolysis by ouabain sensitive Na+, K+-ATP-ase in spermatozoa of infertile men

    Directory of Open Access Journals (Sweden)

    Р. В. Фафула


    Full Text Available Background: It is known that Na+,K+-ATP-ase plays important role in physiology of spermatozoa including their motility. Na+,K+-ATP-ase is one of the targets for reactive oxygen species. Hyperproduction of reactive oxygen species can damage sperm cells and it is considered to be as one of the mechanisms of male infertility. Objectives: To evaluate the H2O2 effect on the main kinetic parameters of ATP hydrolysis by ouabain-sensitive Na+,K+-ATPase of spermatozoa of fertile (normozoospermia and infertility men (asthenozoospermia. Materials and methods: Na+, K+-ATP-ase activity was determined spectrophotometrically by production of Pi. Concentration dependencies ware linearized in Lineweaver-Burk plot. Results: Effective inhibitory effect of H2O2 on ouabain-sensitive Na+,K+-ATP-ase activity of sperm cells of fertile and infertile men was demonstrated. The effects of H2O2 on the main kinetic parameters of the ATP hydrolysis with the involvement of Na+, K+-ATP-ase was studied. In the whole range of studied concentrations of ATP the Na+, K+-ATP-ase activity of spermatozoa of fertile and infertile men was reduced in the presence of H2O2 in the incubation medium. However, the optimal activity of the Na+, K+-ATP-ase activity of sperm cells in both normozoospermic and asthenozoospermic men was observed in the presence of 5 mM ATP in the incubation medium. By linearization of concentration curves in Lineweaver-Burk plot the main kinetic parameters of Na+, K+-activated, Mg2+-dependent ATP hydrolysis in the sperm cells of fertile and infertile men were determined. Under the effect of H2O2, the affinity constant of enzyme to ATP in normozoospermic and asthenozoospermic men increases several times. The initial maximum rate of ATP hydrolysis was significantly reduced only in the spermatozoa of fertile men with normozoospermia. Conclusions: Under conditions of H2O2-induced oxidative stress the inhibition of ouabain-sensitive Na+,K+-ATP-ase activity in sperm cells

  3. Towards a multiscale description of microvascular flow regulation: O2-dependent release of ATP from human erythrocytes and the distribution of ATP in capillary networks

    Directory of Open Access Journals (Sweden)

    Daniel eGoldman


    Full Text Available Integration of the numerous mechanisms that have been suggested to contribute to optimization of O2 supply to meet O2 need in skeletal muscle requires a systems biology approach which permits quantification of these physiological processes over a wide range of length scales. Here we describe two individual computational models based on in vivo and in vitro studies which, when incorporated into a single robust multiscale model, will provide information on the role of erythrocyte-released ATP in perfusion distribution in skeletal muscle under both physiological and pathophysiological conditions. Healthy human erythrocytes exposed to low O2 tension release ATP via a well characterized signaling pathway requiring activation of the G-protein, Gi, and adenylyl cyclase leading to increases in cAMP. This cAMP then activates PKA and subsequently CFTR culminating in ATP release via pannexin 1. A critical control point in this pathway is the level of cAMP which is regulated by pathway-specific phosphodiesterases. Using time constants (~100ms that are consistent with measured erythrocyte ATP release, we have constructed a dynamic model of this pathway. The model predicts levels of ATP release consistent with measurements obtained over a wide range of hemoglobin O2 saturations (sO2. The model further predicts how insulin, at concentrations found in prediabetes, enhances the activity of PDE3 and reduces intracellular cAMP levels leading to decreased low O2-induced ATP release from erythrocytes. The second model, which couples O2 and ATP transport in capillary networks, shows how intravascular ATP and the resulting conducted vasodilation are affected by local sO2, convection and ATP degradation. This model also predicts network-level effects of decreased ATP release resulting from elevated insulin levels. Taken together, these models lay the groundwork for investigating the systems biology of the regulation of microvascular perfusion distribution by

  4. Extracellular ATP inhibits Schwann cell dedifferentiation and proliferation in an ex vivo model of Wallerian degeneration

    International Nuclear Information System (INIS)

    Shin, Youn Ho; Lee, Seo Jin; Jung, Junyang


    Highlights: ► ATP-treated sciatic explants shows the decreased expression of p75NGFR. ► Extracellular ATP inhibits the expression of phospho-ERK1/2. ► Lysosomal exocytosis is involved in Schwann cell dedifferentiation. ► Extracellular ATP blocks Schwann cell proliferation in sciatic explants. -- Abstract: After nerve injury, Schwann cells proliferate and revert to a phenotype that supports nerve regeneration. This phenotype-changing process can be viewed as Schwann cell dedifferentiation. Here, we investigated the role of extracellular ATP in Schwann cell dedifferentiation and proliferation during Wallerian degeneration. Using several markers of Schwann cell dedifferentiation and proliferation in sciatic explants, we found that extracellular ATP inhibits Schwann cell dedifferentiation and proliferation during Wallerian degeneration. Furthermore, the blockage of lysosomal exocytosis in ATP-treated sciatic explants is sufficient to induce Schwann cell dedifferentiation. Together, these findings suggest that ATP-induced lysosomal exocytosis may be involved in Schwann cell dedifferentiation.

  5. ATP-independent DNA synthesis in Vaccinia-infected L cells

    International Nuclear Information System (INIS)

    Berger, N.A.; Kauff, R.A.; Sikorski, G.W.


    Mouse L cells can be made permeable to exogenous nucleotides by a cold shock in 0.01 M Tris . HCl pH 7.8, 0.25 M sucrose, 1 mM EDTA, 30 mM 2-mercaptoethanol and 4 mM MgCl 2 . DNA synthesis in permeabilized L cells requires ATP whereas DNA synthesis in permeabilized L cells that are infected with Vaccinia virus is ATP-independent. Permeabilized L cells that are infected with ultraviolet-irradiated virus show a marked suppression of DNA synthesis which is not corrected by an excess of deoxynucleoside triphosphates and ATP. The ATP-dependent and ATP-independent processes of DNA synthesis are inhibited to the same extent by Mal-Net, pHMB, ara CTP and phosphonoacetate. Concentrations of daunorubicin and cytembena, which cause marked inhibition of the ATP-dependent enzymes, only cause partial inhibition of the ATP-independent enzymes. (Auth.)

  6. ATP Modifies the Proteome of Extracellular Vesicles Released by Microglia and Influences Their Action on Astrocytes

    Directory of Open Access Journals (Sweden)

    Francesco Drago


    Full Text Available Extracellular ATP is among molecules promoting microglia activation and inducing the release of extracellular vesicles (EVs, which are potent mediators of intercellular communication between microglia and the microenvironment. We previously showed that EVs produced under ATP stimulation (ATP-EVs propagate a robust inflammatory reaction among astrocytes and microglia in vitro and in mice with subclinical neuroinflammation (Verderio et al., 2012. However, the proteome of EVs released upon ATP stimulation has not yet been elucidated. In this study we applied a label free proteomic approach to characterize the proteome of EVs released constitutively and during microglia activation with ATP. We show that ATP drives sorting in EVs of a set of proteins implicated in cell adhesion/extracellular matrix organization, autophagy-lysosomal pathway and cellular metabolism, that may influence the response of recipient astrocytes to EVs. These data provide new clues to molecular mechanisms involved in microglia response to ATP and in microglia signaling to the environment via EVs.

  7. Morphometric Characterization of Small Cell Lymphocytic Lymphoma

    Directory of Open Access Journals (Sweden)

    Chisoi Anca


    Full Text Available The morphometry in histopathology is used to characterize cell populations belonging to different tissues and to identify differences in their parameters with prognostic implications. To achieve morphometric examination were selected 6 of 24 cases identified as small cell lymphocytic lymphoma. For each case analysis was done on five fields, for each field measuring the parameters of 20 cells. The studied parameters were for cytoplasm: cytoplasmic area, maximum and minimum cytoplasmic diameter, cytoplasmic perimeter; for nucleus were measured: nuclear area, minimum and maximum nuclear diameter, nuclear perimeter, nuclear contour index, nuclear ellipticity index, nuclear irregularity index. Also the nucleocytoplasmic ratio was calculated in all studied cases. Small cell lymphocytic lymphoma is characterized in morphometric terms having a small cytoplasmic area (average 29.206 and also a small nuclear area (mean 28.939 having a nucleo-cytoplasmic ratio appearance suggestive for adult lymphocyte. A nuclear contour index small value (3.946, ellipticity index value also small (3.521 and small nuclear irregularity index (3.965. Standard deviations, in any of the studied morphometric categories, is around or below 1 suggesting monomorphic cell appearance. These morphometric and microscopic features characterized mainly by a small population of adult lymphocytes, monomorphic, with rounded hipercromic nuclei, dense chromatin, support the framing into indolent lymphoma group in terms of clinical outcome.

  8. Cytokine gene expression of peripheral blood lymphocytes ...

    African Journals Online (AJOL)



    Mar 20, 2009 ... Key words: Lipopolysaccharide, lymphocytes, TLRs, cytokines. INTRODUCTION. Lipopolysaccharide (LPS), a predominant glycolipid in the outer membranes of Gam-negative bacteria, stimulates monocyte, macrophages, and neutrophils and increase expression of cell adhesion molecules (Trent et al., ...

  9. Genotoxic effects of borax on cultured lymphocytes. (United States)

    Pongsavee, Malinee


    The effect of borax on human chromosomes was analyzed in this study. Venous blood from 30 male students at Thammasat University, Thailand (age 18-25 years) was collected for lymphocyte cell cultures. This experiment was divided into two groups: the first group was the control group and the second group was the experimental group. The lymphocyte cells in the control group were cultured without borax. The experimental group was divided into four subgroups. The lymphocyte cells in each experimental subgroup were cultured with different concentrations of borax (0.1 mg/ml, 0.15 mg/ml, 0.2 mg/ml and 0.3 mg/ml). Human chromosomes were studied for abnormalities through Giemsa-staining and G-banding. The results show that the numbers of metaphase plates (the metaphase plate which contained 46 chromosomes; 46, XY) and metaphase chromosomes were reduced when lymphocyte cells were cultured with 0.15 mg/ml (57.2%), 0.2 mg/ml (50.8%) and 0.3 mg/ml (42.3%) concentrations of borax. There was a statistically significant difference between the control and experimental subgroups (p borax concentration experimental subgroup. This shows that borax (at 0.15, 0.2 and 0.3 mg/ml concentrations) affects the cell and human chromosomes (both numerical and structural abnormalities). Borax may cause human chromosome abnormalities and lead to genetic defects.

  10. Immunophenotypic lymphocyte profiles in human african trypanosomiasis.

    Directory of Open Access Journals (Sweden)

    Caroline Boda

    Full Text Available Human African trypanosomiasis (HAT is a deadly vector-born disease caused by an extracellular parasite, the trypanosome. Little is known about the cellular immune responses elicited by this parasite in humans. We used multiparameter flow cytometry to characterize leukocyte immunophenotypes in the blood and cerebrospinal fluid (CSF of 33 HAT patients and 27 healthy controls identified during a screening campaign in Angola and Gabon. We evaluated the subsets and activation markers of B and T lymphocytes. Patients had a higher percentage of CD19+ B lymphocytes and activated B lymphocytes in the blood than did controls, but lacked activated CD4+ T lymphocytes (CD25+. Patients displayed no increase in the percentage of activated CD8+ T cells (HLA-DR+, CD69+ or CD25+, but memory CD8 T-cell levels (CD8+CD45RA2 were significantly lower in patients than in controls, as were effector CD8 T-cell levels (CD8+CD45RA+CD62L2. No relationship was found between these blood immunophenotypes and disease severity (stage 1 vs 2. However, CD19+ B-cell levels in the CSF increased with disease severity. The patterns of T and B cell activation in HAT patients suggest that immunomodulatory mechanisms may operate during infection. Determinations of CD19+ B-cell levels in the CSF could improve disease staging.

  11. Chronic lymphocytic leukaemia manifestating as exfoliative dermatitis

    Directory of Open Access Journals (Sweden)

    Dhir R


    Full Text Available A 60-year-old patient reported with a history of redness and peeling of the skin, and sensations of chills and tightness of the skin of three months duration. Clinical examination revealed exfoliative dermatitis, generalised lymphadenopathy and hepatosplenomegely. A peripheral smear showed features of chronic lymphocytic leukaemia.

  12. Neutrophil Lymphocyte Ratio Predicts Postoperative Pain after ...

    African Journals Online (AJOL)

    Background and Aim: Postoperative pain is well known and usually disturbing complication of surgery. Inflammation plays an important role in the development and progression of postoperative pain. We aimed to investigate possible relationship between preoperatively measured neutrophil‑lymphocyte ratio (NLR) – as an ...

  13. GABA, a natural immunomodulator of T lymphocytes

    DEFF Research Database (Denmark)

    Bjurstöm, Helen; Wang, Junyang; Ericsson, Ida


    gamma-aminobutyric acid (GABA) is the main neuroinhibitory transmitter in the brain. Here we show that GABA in the extracellular space may affect the fate of pathogenic T lymphocytes entering the brain. We examined in encephalitogenic T cells if they expressed functional GABA channels that could...

  14. [Stabilization of Cadmium Contaminated Soils by Ferric Ion Modified Attapulgite (Fe/ATP)--Characterizations and Stabilization Mechanism]. (United States)

    Rong, Yang; Li, Rong-bo; Zhou, Yong-li; Chen, Jing; Wang, Lin-ling; Lu, Xiao-hua


    Ferric ion modified attapulgite (Fe/ATP) was prepared by impregnation and its structure and morphology were characterized. The toxicity characteristic leaching procedure (TCLP) was used to evaluate the effect of Cadmium( Cd) stabilization in soil with the addition of attapulgite (ATP) and Fe/ATP. The stabilization mechanism of Cd was further elucidated by comparing the morphologies and structure of ATP and Fe/ATP before and after Cd adsorption. Fe/ATP exhibited much better adsorption capacity than ATP, suggesting different adsorption mechanisms occurred between ATP and Fe/ATP. The leaching concentrations of Cd in soil decreased by 45% and 91% respectively, with the addition of wt. 20% ATP and Fe/ATP. The former was attributed to the interaction between Cd2 and --OH groups by chemical binding to form inner-sphere complexes in ATP and the attachment between Cd2+ and the defect sites in ATP framework. Whereas Cd stabilization with Fe/ATP was resulted from the fact that the active centers (--OH bonds or O- sites) on ATP could react with Fe3+ giving Fe--O--Cd-- bridges, which helped stabilize Cd in surface soil. What'more, the ferric oxides and metal hydroxides on the surface of ATP could interact with Cd, probably by the formation of cadmium ferrite. In conclusion, Fe/ATP, which can be easily prepared, holds promise as a potential low-cost and environmental friendly stabilizing agent for remediation of soil contaminated with heavy metals.

  15. Persistence of the mitochondrial permeability transition in the absence of subunit c of human ATP synthase. (United States)

    He, Jiuya; Ford, Holly C; Carroll, Joe; Ding, Shujing; Fearnley, Ian M; Walker, John E


    The permeability transition in human mitochondria refers to the opening of a nonspecific channel, known as the permeability transition pore (PTP), in the inner membrane. Opening can be triggered by calcium ions, leading to swelling of the organelle, disruption of the inner membrane, and ATP synthesis, followed by cell death. Recent proposals suggest that the pore is associated with the ATP synthase complex and specifically with the ring of c-subunits that constitute the membrane domain of the enzyme's rotor. The c-subunit is produced from three nuclear genes, ATP5G1 , ATP5G2 , and ATP5G3 , encoding identical copies of the mature protein with different mitochondrial-targeting sequences that are removed during their import into the organelle. To investigate the involvement of the c-subunit in the PTP, we generated a clonal cell, HAP1-A12, from near-haploid human cells, in which ATP5G1 , ATP5G2 , and ATP5G3 were disrupted. The HAP1-A12 cells are incapable of producing the c-subunit, but they preserve the characteristic properties of the PTP. Therefore, the c-subunit does not provide the PTP. The mitochondria in HAP1-A12 cells assemble a vestigial ATP synthase, with intact F 1 -catalytic and peripheral stalk domains and the supernumerary subunits e, f, and g, but lacking membrane subunits ATP6 and ATP8. The same vestigial complex plus associated c-subunits was characterized from human 143B ρ 0 cells, which cannot make the subunits ATP6 and ATP8, but retain the PTP. Therefore, none of the membrane subunits of the ATP synthase that are involved directly in transmembrane proton translocation is involved in forming the PTP.

  16. Evaluation of ATP measurements to detect microbial ingress by wastewater and surface water in drinking water. (United States)

    Vang, Óluva K; Corfitzen, Charlotte B; Smith, Christian; Albrechtsen, Hans-Jørgen


    Fast and reliable methods are required for monitoring of microbial drinking water quality in order to protect public health. Adenosine triphosphate (ATP) was investigated as a potential real-time parameter for detecting microbial ingress in drinking water contaminated with wastewater or surface water. To investigate the ability of the ATP assay in detecting different contamination types, the contaminant was diluted with non-chlorinated drinking water. Wastewater, diluted at 10(4) in drinking water, was detected with the ATP assay, as well as 10(2) to 10(3) times diluted surface water. To improve the performance of the ATP assay in detecting microbial ingress in drinking water, different approaches were investigated, i.e. quantifying microbial ATP or applying reagents of different sensitivities to reduce measurement variations; however, none of these approaches contributed significantly in this respect. Compared to traditional microbiological methods, the ATP assay could detect wastewater and surface water in drinking water to a higher degree than total direct counts (TDCs), while both heterotrophic plate counts (HPC 22 °C and HPC 37 °C) and Colilert-18 (Escherichia coli and coliforms) were more sensitive than the ATP measurements, though with much longer response times. Continuous sampling combined with ATP measurements displays definite monitoring potential for microbial drinking water quality, since microbial ingress in drinking water can be detected in real-time with ATP measurements. The ability of the ATP assay to detect microbial ingress is influenced by both the ATP load from the contaminant itself and the ATP concentration in the specific drinking water. Consequently, a low ATP concentration of the specific drinking water facilitates a better detection of a potential contamination of the water supply with the ATP assay. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Modulation of nucleotide sensitivity of ATP-sensitive potassium channels by phosphatidylinositol-4-phosphate 5-kinase. (United States)

    Shyng, S L; Barbieri, A; Gumusboga, A; Cukras, C; Pike, L; Davis, J N; Stahl, P D; Nichols, C G


    ATP-sensitive potassium channels (K(ATP) channels) regulate cell excitability in response to metabolic changes. K(ATP) channels are formed as a complex of a sulfonylurea receptor (SURx), a member of the ATP-binding cassette protein family, and an inward rectifier K(+) channel subunit (Kir6.x). Membrane phospholipids, in particular phosphatidylinositol (PI) 4,5-bisphosphate (PIP(2)), activate K(ATP) channels and antagonize ATP inhibition of K(ATP) channels when applied to inside-out membrane patches. To examine the physiological relevance of this regulatory mechanism, we manipulated membrane PIP(2) levels by expressing either the wild-type or an inactive form of PI-4-phosphate 5-kinase (PIP5K) in COSm6 cells and examined the ATP sensitivity of coexpressed K(ATP) channels. Channels from cells expressing the wild-type PIP5K have a 6-fold lower ATP sensitivity (K(1/2), the half maximal inhibitory concentration, approximately 60 microM) than the sensitivities from control cells (K(1/2) approximately 10 microM). An inactive form of the PIP5K had little effect on the K(1/2) of wild-type channels but increased the ATP-sensitivity of a mutant K(ATP) channel that has an intrinsically lower ATP sensitivity (from K(1/2) approximately 450 microM to K(1/2) approximately 100 microM), suggesting a decrease in membrane PIP(2) levels as a consequence of a dominant-negative effect of the inactive PIP5K. These results show that PIP5K activity, which regulates PIP(2) and PI-3,4,5-P(3) levels, is a significant determinant of the physiological nucleotide sensitivity of K(ATP) channels.

  18. DMPD: Developmental plasticity of lymphocytes. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 18472258 Developmental plasticity of lymphocytes. Cobaleda C, Busslinger M. Curr Immunol. 2008 Apr;20(2):139-48. Epub 2008 May 9. (.png) (.svg) (.html) (.csml) Show Developmental plastic...ity of lymphocytes. PubmedID 18472258 Title Developmental plasticity of lymphocytes. Authors Cobaleda C, Bus

  19. Chronic lymphocytic leukemia/small lymphocytic lymphoma presenting as septic arthritis of the shoulder

    Energy Technology Data Exchange (ETDEWEB)

    Donovan, Andrea; Schweitzer, Mark E.; Nomikos, George [NYU Hospital for Joint Diseases, New York, NY (United States); Garcia, Roberto A. [Bellevue Hospital Center, New York, NY (United States)


    We report a case of a 53-year-old man presenting with shoulder pain mimicking septic arthritis. Laboratory findings were atypical. Biopsy performed to assess for possible osteomyelitis demonstrated chronic lymphocytic leukemia/small lymphocytic lymphoma. Intra-articular lymphoma is a rare but important consideration in patients with atypical clinical presentation. Imaging alone may be insufficient to render diagnosis as lymphoma can mimic infection, synovial hypertrophic processes, and depositional arthropathy. (orig.)

  20. Excessive extracellular ATP desensitizes P2Y2 and P2X4 ATP receptors provoking surfactant impairment ending in ventilation-induced lung injury

    NARCIS (Netherlands)

    D. Hasan (Djo); Satalin, J. (Joshua); van der Zee, P. (Philip); Kollisch-Singule, M. (Michaela); P. Blankman (Paul); Shono, A. (Atsuko); P. Somhorst (Peter); C.A. den Uil (Corstiaan); H.J. Meeder (Han); Kotani, T. (Toru); G.F. Nieman (Gary F.)


    textabstractStretching the alveolar epithelial type I (AT I) cells controls the intercellular signaling for the exocytosis of surfactant by the AT II cells through the extracellular release of adenosine triphosphate (ATP) (purinergic signaling). Extracellular ATP is cleared by extracellular ATPases,

  1. Local release of ATP into the arterial inflow and venous drainage of human skeletal muscle: insight from ATP determination with the intravascular microdialysis technique

    DEFF Research Database (Denmark)

    Mortensen, Stefan; Thaning, Pia; Nyberg, Michael Permin


    is released into plasma, we measured plasma [ATP] with the intravascular microdialysis technique at rest and during dynamic exercise (normoxia and hypoxia), passive exercise, thigh compressions and arterial ATP, tyramine and ACh infusion in a total of 16 healthy young men. Femoral arterial and venous...

  2. Fas expression on peripheral blood lymphocytes in systemic lupus erythematosus (SLE) : relation to lymphocyte activation and disease activity

    NARCIS (Netherlands)

    Bijl, M; Horst, G; Limburg, PC; Kallenberg, CGM


    Levels of apoptotic lymphocytes have been found to be increased in SLE and persistence of apoptotic cells has been associated with autoantibody production, Increased lymphocyte Fas (CD95) expression due to lymphocyte activation may account for increased Susceptibility to Fas-mediated apoptosis in

  3. Air-Stimulated ATP Release from Keratinocytes Occurs through Connexin Hemichannels (United States)

    Barr, Travis P.; Albrecht, Phillip J.; Hou, Quanzhi; Mongin, Alexander A.; Strichartz, Gary R.; Rice, Frank L.


    Cutaneous ATP release plays an important role in both epidermal stratification and chronic pain, but little is known about ATP release mechanisms in keratinocytes that comprise the epidermis. In this study, we analyzed ATP release from cultured human neonatal keratinocytes briefly exposed to air, a process previously demonstrated to trigger ATP release from these cells. We show that exposing keratinocytes to air by removing media for 15 seconds causes a robust, long-lasting ATP release. This air-stimulated ATP release was increased in calcium differentiated cultures which showed a corresponding increase in connexin 43 mRNA, a major component of keratinocyte hemichannels. The known connexin hemichannel inhibitors 1-octanol and carbenoxolone both significantly reduced air-stimulated ATP release, as did two drugs traditionally used as ABC transporter inhibitors (glibenclamide and verapamil). These same 4 inhibitors also prevented an increase in the uptake of a connexin permeable dye induced by air exposure, confirming that connexin hemichannels are open during air-stimulated ATP release. In contrast, activity of the MDR1 ABC transporter was reduced by air exposure and the drugs that inhibited air-stimulated ATP release had differential effects on this transporter. These results indicate that air exposure elicits non-vesicular release of ATP from keratinocytes through connexin hemichannels and that drugs used to target connexin hemichannels and ABC transporters may cross-inhibit. Connexins represent a novel, peripheral target for the treatment of chronic pain and dermatological disease. PMID:23457608

  4. Membrane-associated proteolytic activity in Escherichia coli that is stimulated by ATP

    International Nuclear Information System (INIS)

    Klemes, Y.; Voellmy, R.W.; Goldberg, A.L.


    The degradation of proteins in bacteria requires metabolism energy. One important enzyme in this process is protease La, a soluble ATP-dependent protease encoded by the lon gene. However, lon mutants that lack a functional protease La still show some ATP-dependent protein breakdown. The authors have reported an ATP-stimulated endoproteolytic activity associated with the inner membrane of E. coli. This ATP-stimulated activity is found in normal levels in membranes derived from lon mutants, including strains carrying insertions in the lon gene. The membrane-bound activity hydrolyzes 14 C-methylglobin at a linear rate for up to 3 hours. These fractions also contain appreciable proteolytic activity that is not affected by ATP. The stimulation by ATP requires the presence of Mg 2+ . Nonhydrolyzable ATP analogs (e.g. AMPPNP or ATP-γ-S) and ADP do not enhance proteolysis. Unlike protease La, the membrane-associated enzyme does not degrade the fluorometric substrate, Glt-Ala-Ala-Phe-MNA, in an ATP-stimulated fashion, and its level is not influenced by high temperature of by the gene which regulates the heat-shock response. The enzyme is inhibited by dichloroisocoumarin and certain peptide chloromethyl ketones. They conclude that E. coli contain at least two ATP-dependent proteases with distinct specificities: one is soluble and the other is membrane-associated

  5. Optimum ratio of AET, ATP and serotonin applied in combinations determined with a reference to their toxicity

    International Nuclear Information System (INIS)

    Benova, D.K.; P''tev, I.Kh.


    In experiments on mice, a study was made of the quantitative dependence of toxicity of AET, ATP and serotonin applied in combinations. The toxicity decreased when ATP was combined with AET and increased when ATP of AET were combined with serotonin. The toxicity of a combination of all three substances was reduced by introducing high doses of ATP

  6. Bcl-2 protects against apoptosis induced by antimycin A and bongkrekic acid without restoring cellular ATP levels.

    NARCIS (Netherlands)

    Graaf, A.O. de; Meijerink, J.P.P.; Heuvel, L.P.W.J. van den; Abreu, R.A. de; Witte, T.J.M. de; Jansen, J.H.; Smeitink, J.A.M.


    Several studies indicate that mitochondrial ATP production as well as ADP/ATP exchange across mitochondrial membranes are impaired during apoptosis. We investigated whether Bcl-2 could protect against cell death under conditions in which ATP metabolism is inhibited. Inhibition of ATP production

  7. A divergent ADP/ATP carrier in the hydrogenosomes of Trichomonas gallinae argues for an independent origin of these organelles.

    NARCIS (Netherlands)

    Tjaden, J.; Haferkamp, I.; Boxma, B.; Tielens, A.G.; Huynen, M.A.; Hackstein, J.H.P.


    The evolution of mitochondrial ADP and ATP exchanging proteins (AACs) highlights a key event in the evolution of the eukaryotic cell, as ATP exporting carriers were indispensable in establishing the role of mitochondria as ATP-generating cellular organelles. Hydrogenosomes, i.e. ATP- and

  8. A comparative study of radioprotective effect of several antioxidants on human blood lymphocytes

    International Nuclear Information System (INIS)

    Wang Mingsuo; Zhu Gengbai; Gu Xuandi


    By means of improved fluorometric method with 2-thiobarbituric acid (TBA) as the fluorometric agent, radioprotective effects of four kinds of antioxidants on 60 Co γ-ray induced lipid peroxidation (LPO) level, i.e. Malondialdehyde (MDA) content changes in human blood lymphocytes were in human blood lymphocytes were compared by using relative protective efficiency (RPE) as an indicator. The LPO level in human lymphocytes which had been treated with an antioxidant at an concentration of 5 x 10 -3 g/L for 1 hr was measured 2 hr after exposure to 4 Gy of γ-rays, and the RPE values of antioxidants were calculated under these conditions: SOD, 38.23; VE, 23.75:VC, 19.32 and Se +4 , 18.27, thus the anticipation that the compounds, superoxide dismutase (SOD), 2-tocopherols (VE), ascorbic acid (VC) and Na 2 SeO 3 (Se +4 ) had radioprotective effects was confirmed. It was found that the radioprotective beneficial sequences of four kinds of antioxidants were arranged as SOD>VE>VC,Se +4 . The results show that radioprotective effects of exogenous antioxidants on radiation induced LPO damage are dependent not only on irradiation dosage, but also especially on property of antioxidants, drug concentration, pretreatment and monitoring time, etc. The mechanism of these antioxidants effecting as radioprotectants on human lymphocytes is discussed in connection with LPO damage and radioprotection

  9. Measurement of exercise-induced oxidative stress in lymphocytes. (United States)

    Turner, James E; Bosch, Jos A; Aldred, Sarah


    Vigorous exercise is associated with oxidative stress, a state that involves modifications to bodily molecules due to release of pro-oxidant species. Assessment of such modifications provides non-specific measures of oxidative stress in human tissues and blood, including circulating lymphocytes. Lymphocytes are a very heterogeneous group of white blood cells, consisting of subtypes that have different functions in immunity. Importantly, exercise drastically changes the lymphocyte composition in blood by increasing the numbers of some subsets, while leaving other cells unaffected. This fact may imply that observed changes in oxidative stress markers are confounded by changes in lymphocyte composition. For example, lymphocyte subsets may differ in exposure to oxidative stress because of subset differences in cell division and the acquisition of cytotoxic effector functions. The aim of the present review is to raise awareness of interpretational issues related to the assessment of oxidative stress in lymphocytes with exercise and to address the relevance of lymphocyte subset phenotyping in these contexts.

  10. Genetic variation in ATP5O is associated with skeletal muscle ATP50 mRNA expression and glucose uptake in young twins.

    Directory of Open Access Journals (Sweden)

    Tina Rönn

    Full Text Available BACKGROUND: Impaired oxidative capacity of skeletal muscle mitochondria contribute to insulin resistance and type 2 diabetes (T2D. Furthermore, mRNA expression of genes involved in oxidative phosphorylation, including ATP5O, is reduced in skeletal muscle from T2D patients. Our aims were to investigate mechanisms regulating ATP5O expression in skeletal muscle and association with glucose metabolism, and the relationship between ATP5O single nucleotide polymorphisms (SNPs and risk of T2D. METHODOLOGY/PRINCIPAL FINDINGS: ATP5O mRNA expression was analyzed in skeletal muscle from young (n = 86 and elderly (n = 68 non-diabetic twins before and after a hyperinsulinemic euglycemic clamp. 11 SNPs from the ATP5O locus were genotyped in the twins and a T2D case-control cohort (n = 1466. DNA methylation of the ATP5O promoter was analyzed in twins (n = 22 using bisulfite sequencing. The mRNA level of ATP5O in skeletal muscle was reduced in elderly compared with young twins, both during basal and insulin-stimulated conditions (p<0.0005. The degree of DNA methylation around the transcription start of ATP5O was <1% in both young and elderly twins and not associated with mRNA expression (p = 0.32. The mRNA level of ATP5O in skeletal muscle was positively related to insulin-stimulated glucose uptake (regression coefficient = 6.6; p = 0.02. Furthermore, two SNPs were associated with both ATP5O mRNA expression (rs12482697: T/T versus T/G; p = 0.02 and rs11088262: A/A versus A/G; p = 0.004 and glucose uptake (rs11088262: A/A versus A/G; p = 0.002 and rs12482697: T/T versus T/G; p = 0.005 in the young twins. However, we could not detect any genetic association with T2D. CONCLUSIONS/SIGNIFICANCE: Genetic variation and age are associated with skeletal muscle ATP5O mRNA expression and glucose disposal rate, suggesting that combinations of genetic and non-genetic factors may cause the reduced expression of ATP5O in T2D muscle. These findings propose a role for ATP5O, in

  11. Effect of Vibrio cholerae neuraminidase on the mitogen response of T lymphocytes. I. Enhancement of macrophage T-lymphocyte cooperation in concanavalin-A-induced lymphocyte activation. (United States)

    Knop, J


    Vibrio cholerae neuraminidase (VCN) enhances the immune response of lymphocytes in various systems, such as antigen- and mitogen-induced blastogenesis, mixed lymphocyte culture (MLC) and tumor-cell response. We used macrophage-depleted and reconstituted murine lymph-node T-cells to investigate the effect of VCN on macrophage-T-lymphocyte co-operation in Con-A-induced lymphocyte activation. In unfractionated lymph-node cells VCN enhanced the Con-A-induced lymphocyte activation as measured by 3H-thymidine (3H-dThd) incorporation. Removing macrophages from the cells resulted in a significantly diminished response. In addition the enhancing effect of VCN was greatly reduced. Reconstitution of the lymphocyte cultures with macrophages in increasing numbers and from various sources rstored the lymphocyte response and the enhancing effect of VCN. VCN proved to be most efficient in cultures reconstituted with normal peritoneal macrophages. Some effect was also observed using bone-marrow-derived (BM) macrophages. However, higher numbers of normal PE macrophages in the presence of VCN inhibited lymphocyte activation, and inhibition by thioglycollate-broth-induced macrophages was considerably increased by VCN. These results suggest that VCN acts by increasing the efficiency of macrophage-T lymphocyte interaction.

  12. Gamma-radiation effect of the ATP-ASE-activity in various parts of cotton sprouts

    International Nuclear Information System (INIS)

    Kazimov, A.K.


    ATP-ase is a thiol enzyme whose sulfhydryl group plays an important role. The transport of substances through biological membranes is the result of the action of the sodium-potassium pump of the cell, which functions with ATP energy. The action of this transport mechanism depends on the activity of ATP-ase. It may be postulated, therefore, that the suppression of the active transport of Na + and K + ions in cells under irradiation is partially the result of a disturbance of the activity of the ATP enzyme system. The author studied the effect of gamma radiation on ATP-ase activity in various parts of seven-day-old seedlings of type 108-F cotton, which were irradiated using Co 60 gamma radiation. The results of the experiment showed that the ATP-ase activity of the cotton seedling rootlets depends on the dose and the time elapsed after irradiation (a table is given). Small radiation doses (0.2 and 0.5 krad) significantly increased ATP-ase activity in the rootlets, while heavy doses inhibited it significantly. Similar results were obtained for the stems and leaves (tables are given). It was estblished that the ATP-ase of cotton seedlings has varying sensitivity to irradiation. The most sensitive ATP-ases were those of the rootlets. The activity of background ATP-ase is less subject to change than Na + and K + activated ATP-ases. For example, while the activity of ATP-ase (without ions) was inhibited by 25% when a 25 krad irradiation dose was administered, the retardation of Na + and K + activated ATP-ases reached 41%. The author suggests that the inhibition of ATP-ase activity under irradiation is mainly the result of a disturbance of the structure of the membrane functions. It is also possible that ATP-ase activity decreases because of a lack of the enzyme substrate - ATP, which is formed during the process of oxydative phosphorylization. A table is also provided showing the effect of irradiation on the activity of ATP-ase activated by various ions in the roots of

  13. Characteristics of T lymphocyte subpopulations 

    Directory of Open Access Journals (Sweden)

    Paulina Niedźwiedzka-Rystwej


    Full Text Available The paper describes the characteristics, receptor profile and functions of T lymphocyte subpopulations (helper, cytotoxic, regulatory, memory and others. Among T helper cells one can enumerate Th0, Th1, Th2, Th9, Th17, Th22, TFH and nTh2, while T cytotoxic cells include Tc, NKT, Tγδ, and T CD8αα (IEL. Among regulatory cells there are nTreg, iTreg, TR1, and iTR35, as well as T lymphocytes with CD8, such as CD8 CD122 , CD8 CD28-, and CD11c CD8 . And among memory T cells there are Tcm and Tem. Moreover, there are some so-called other T cells, such as Tn (T αβ CD4 and T αβ CD8 , T exhausted and T anergic. 

  14. Biological Prognostic Markers in Chronic Lymphocytic Leukemia

    Directory of Open Access Journals (Sweden)

    Vladimíra Vroblová


    Full Text Available Chronic lymphocytic leukemia (CLL is the most frequent leukemic disease of adults in the Western world. It is remarkable by an extraordinary heterogeneity of clinical course with overall survival ranging from several months to more than 15 years. Classical staging sytems by Rai and Binet, while readily available and useful for initial assessment of prognosis, are not able to determine individual patient’s ongoing clinical course of CLL at the time of diagnosis, especially in early stages. Therefore, newer biological prognostic parameters are currently being clinically evaluated. Mutational status of variable region of immunoglobulin heavy chain genes (IgVH, cytogenetic aberrations, and both intracellular ZAP- 70 and surface CD38 expression are recognized as parameters with established prognostic value. Molecules regulating the process of angiogenesis are also considered as promising markers. The purpose of this review is to summarize in detail the specific role of these prognostic factors in chronic lymphocytic leukemia.

  15. Lymphocytic subsets and low-dose exposure

    International Nuclear Information System (INIS)

    Tuschl, H.; Kovac, R.; Eybl, E.


    The present investigations proved the differential radiosensitivity of lymphocytic subpopulations: From in vivo and in vitro irradiations it may be followed that the most sensitive subset are CD8 positive suppressor T cells. CD4/CD8 ratios are increased both in peripheral blood and after mitogen stimulation of lymphocytes of exposed persons. The decrease in B cells is pronounced only at higher radiation doses. Though the rate of DNA synthesis after mitogen stimulation was reduced in some exposed persons, that was no general phenomenon. Especially after tritium exposure, the observed lymphopenia correlated with an increased stimulation by PHA and an increased rate of DNA synthesis in some probands. Thus the present investigations indicate that - despite an inhibition of some immune parameters by radioexposure - the body is able to maintain its immunological homoeostasis. (authors)

  16. Effect of extraluminal ATP application on vascular tone and blood flow in skeletal muscle

    DEFF Research Database (Denmark)

    Nyberg, Michael Permin; Al-Khazraji, Baraa K; Mortensen, Stefan P


    During skeletal muscle contractions, the concentration of ATP increases in muscle interstitial fluid as measured by microdialysis probes. This increase is associated with the magnitude of blood flow, suggesting that interstitial ATP may be important for contraction-induced vasodilation. However...... studied. The rat gluteus maximus skeletal muscle model was used to study changes in local skeletal muscle hemodynamics. Superfused ATP at concentrations found during muscle contractions (1-10 µM) increased blood flow by up to 400%. In this model, the underlying mechanism was also examined by inhibition...... in interstitial ATP concentrations increases muscle blood flow, indicating that the contraction-induced increase in skeletal muscle interstitial [ATP] is important for exercise hyperemia. The vasodilator effect of ATP application is mediated by NO and prostanoid formation....

  17. ATP secretion from nerve trunks and Schwann cells mediated by glutamate. (United States)

    Liu, Guo Jun; Bennett, Max R


    ATP release from rat sciatic nerves and from cultured Schwann cells isolated from the nerves was investigated using an online bioluminescence technique. ATP was released in relatively large amounts from rat sciatic nerve trunks during electrical stimulation. This release was blocked by the sodium channel inhibitor tetrodotoxin and the non-NMDA glutamate receptor blocker 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX). Schwann cells isolated from the nerve trunks did not release ATP when electrically stimulated but did in response to glutamate in a concentration-dependent manner. Glutamate-stimulated ATP release was inhibited by specific non-competitive AMPA receptor antagonist GYKI 52466 and competitive non-NMDA receptor antagonist CNQX. Glutamate-stimulated ATP release was decreased by inhibition of anion transporter inhibitors by furosemide, cystic fibrosis transmembrane conductance regulator by glibenclamide and exocytosis by botulinum toxin A, indicating that anion transporters and exocytosis provide the main secretion mechanisms for ATP release from the Schwann cells.

  18. Genetic dysfunction of MT-ATP6 causes axonal Charcot-Marie-Tooth disease.

    LENUS (Irish Health Repository)

    Pitceathly, Robert D S


    Charcot-Marie-Tooth (CMT) disease is the most common inherited neuromuscular disorder, affecting 1 in 2,500 individuals. Mitochondrial DNA (mtDNA) mutations are not generally considered within the differential diagnosis of patients with uncomplicated inherited neuropathy, despite the essential requirement of ATP for axonal function. We identified the mtDNA mutation m.9185T>C in MT-ATP6, encoding the ATP6 subunit of the mitochondrial ATP synthase (OXPHOS complex V), at homoplasmic levels in a family with mitochondrial disease in whom a severe motor axonal neuropathy was a striking feature. This led us to hypothesize that mutations in the 2 mtDNA complex V subunit encoding genes, MT-ATP6 and MT-ATP8, might be an unrecognized cause of isolated axonal CMT and distal hereditary motor neuropathy (dHMN).

  19. Facile conversion of ATP-binding RNA aptamer to quencher-free molecular aptamer beacon. (United States)

    Park, Yoojin; Nim-Anussornkul, Duangrat; Vilaivan, Tirayut; Morii, Takashi; Kim, Byeang Hyean


    We have developed RNA-based quencher-free molecular aptamer beacons (RNA-based QF-MABs) for the detection of ATP, taking advantage of the conformational changes associated with ATP binding to the ATP-binding RNA aptamer. The RNA aptamer, with its well-defined structure, was readily converted to the fluorescence sensors by incorporating a fluorophore into the loop region of the hairpin structure. These RNA-based QF-MABs exhibited fluorescence signals in the presence of ATP relative to their low background signals in the absence of ATP. The fluorescence emission intensity increased upon formation of a RNA-based QF-MAB·ATP complex. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Methodological problems of direct bioluminescent ATP assay in platelets and erythrocytes. (United States)

    Girotti, S; Ferri, E; Cascione, M L; Comuzio, S; Mazzuca, A; Orlandini, A; Breccia, A


    Direct bioluminescent ATP determination in platelets and erythrocytes involves the study of different parameters which are discussed here. Some parameters are linked to the bioluminescent reaction and to the analyte (ATP); others have regard to the biological matrix. The composition of bioluminescent reagents and the preparation and conservation of the ATP standard, also in the presence of excipients, are among the first given. Matrix problems involve cell characteristics related to age and form, lysis resistance and the possible formation of aggregates (platelets) that may inhibit the complete release of ATP. For these reasons we used the most efficient ATP release agent with the lowest inhibitory effect on luciferase. The data obtained correlate well with a bioluminescent method requiring extraction with ethanol/EDTA, and therefore more time, for ATP determination in platelets and erythrocytes.

  1. Antihypertrophic Effects of Small Molecules that Maintain Mitochondrial ATP Levels Under Hypoxia

    Directory of Open Access Journals (Sweden)

    Hiroaki Nagai


    Full Text Available Since impaired mitochondrial ATP production in cardiomyocytes is thought to lead to heart failure, a drug that protects mitochondria and improves ATP production under disease conditions would be an attractive treatment option. In this study, we identified small-molecule drugs, including the anti-parasitic agent, ivermectin, that maintain mitochondrial ATP levels under hypoxia in cardiomyocytes. Mechanistically, transcriptomic analysis and gene silencing experiments revealed that ivermectin increased mitochondrial ATP production by inducing Cox6a2, a subunit of the mitochondrial respiratory chain. Furthermore, ivermectin inhibited the hypertrophic response of human induced pluripotent stem cell-derived cardiomyocytes. Pharmacological inhibition of importin β, one of the targets of ivermectin, exhibited protection against mitochondrial ATP decline and cardiomyocyte hypertrophy. These findings indicate that maintaining mitochondrial ATP under hypoxia may prevent hypertrophy and improve cardiac function, providing therapeutic options for mitochondrial dysfunction.

  2. ATP-loading 201Tl myocardial SPECT for the detection of ischemic heart disease

    International Nuclear Information System (INIS)

    Fujinaga, Tsuyoshi; Yamazaki, Sayaka; Hara, Masatada; Umezawa, Chiaki; Okamura, Tetsuo; Murata, Hajime; Maruno, Hirotaka; Onoguchi, Masahisa.


    To evaluate the usefulness for the detection of ischemic heart disease, ATP myocrdial SPECT was performed in 35 patients (mean; 59±9.4 years) with angina pectoris or old myocardial infarction. Coronary angiography (CAG) was performed in all patients. The ultra-short half-life of ATP required a continuous infusion for its use. ATP was infused intravenously at a rate of 0.16 mg/kg/min for 5 min, with 201 Tl injection taking place at 3 min. Myocardial SPECT imaging was begun 5 min and 4 hr later after the end of ATP infusion. ATP caused a significant decrease in arterial blood pressure (p 201 Tl myocardial SPECT for the detection of coronary artery disease (CAD) was evaluated using CAG as a golden standard. The sensitivity and specificity for CAD detection were 82% and 90%, respectively. ATP myocardial SPECT is a promising new test for the detection of ischemic heart disease. (author)

  3. Disruption of Intracellular ATP Generation and Tight Junction Protein Expression during the Course of Brain Edema Induced by Subacute Poisoning of 1,2-Dichloroethane

    Directory of Open Access Journals (Sweden)

    Gaoyang Wang


    Full Text Available The aim of this study was to explore changes in intracellular ATP generation and tight junction protein expression during the course of brain edema induced by subacute poisoning of 1,2-dichloroethane (1,2-DCE. Mice were exposed to 1.2 g/m3 1,2-DCE for 3.5 h per day for 1, 2, or 3 days, namely group A, B, and C. Na+-K+-ATPase and Ca2+-ATPase activity, ATP and lactic acid content, intracellular free Ca2+ concentration and ZO-1 and occludin expression in the brain were measured. Results of present study disclosed that Ca2+-ATPase activities in group B and C, and Na+/K+-ATPase activity in group C decreased, whereas intracellular free Ca2+ concentrations in group B and C increased significantly compared with control. Moreover, ATP content decreased, whereas lactic acid content increased significantly in group C compared with control. On the other hand, expressions of ZO-1 and occludin at both the protein and gene levels in group B and C decreased significantly compared with control. In conclusion, findings from this study suggest that calcium overload and depressed expression of tight junction associated proteins, such as ZO-1 and occludin might play an important role in the early phase of brain edema formation induced by subacute poisoning of 1,2-DCE.

  4. Excessive Extracellular ATP Desensitizes P2Y2 and P2X4 ATP Receptors Provoking Surfactant Impairment Ending in Ventilation-Induced Lung Injury

    Directory of Open Access Journals (Sweden)

    Djo Hasan


    Full Text Available Stretching the alveolar epithelial type I (AT I cells controls the intercellular signaling for the exocytosis of surfactant by the AT II cells through the extracellular release of adenosine triphosphate (ATP (purinergic signaling. Extracellular ATP is cleared by extracellular ATPases, maintaining its homeostasis and enabling the lung to adapt the exocytosis of surfactant to the demand. Vigorous deformation of the AT I cells by high mechanical power ventilation causes a massive release of extracellular ATP beyond the clearance capacity of the extracellular ATPases. When extracellular ATP reaches levels >100 μM, the ATP receptors of the AT II cells become desensitized and surfactant impairment is initiated. The resulting alteration in viscoelastic properties and in alveolar opening and collapse time-constants leads to alveolar collapse and the redistribution of inspired air from the alveoli to the alveolar ducts, which become pathologically dilated. The collapsed alveoli connected to these dilated alveolar ducts are subject to a massive strain, exacerbating the ATP release. After reaching concentrations >300 μM extracellular ATP acts as a danger-associated molecular pattern, causing capillary leakage, alveolar space edema, and further deactivation of surfactant by serum proteins. Decreasing the tidal volume to 6 mL/kg or less at this stage cannot prevent further lung injury.

  5. Purification, crystallization and preliminary X-ray diffraction analysis of the putative ABC transporter ATP-binding protein from Thermotoga maritima

    International Nuclear Information System (INIS)

    Ethayathulla, Abdul S.; Bessho, Yoshitaka; Shinkai, Akeo; Padmanabhan, Balasundaram; Singh, Tej P.; Kaur, Punit; Yokoyama, Shigeyuki


    The putative ABC transporter ATP-binding protein TM0222 from T. maritima was cloned, overproduced, purified and crystallized. A complete MAD diffraction data set has been collected to 2.3 Å resolution. Adenosine triphosphate (ATP) binding cassette transporters (ABC transporters) are ATP hydrolysis-dependent transmembrane transporters. Here, the overproduction, purification and crystallization of the putative ABC transporter ATP-binding protein TM0222 from Thermotoga maritima are reported. The protein was crystallized in the hexagonal space group P6 4 22, with unit-cell parameters a = b = 148.49, c = 106.96 Å, γ = 120.0°. Assuming the presence of two molecules in the asymmetric unit, the calculated V M is 2.84 Å 3 Da −1 , which corresponds to a solvent content of 56.6%. A three-wavelength MAD data set was collected to 2.3 Å resolution from SeMet-substituted TM0222 crystals. Data sets were collected on the BL38B1 beamline at SPring-8, Japan

  6. E-NTPDase and E-ADA activities in lymphocytes associated with the immune response of rats experimentally infected with Toxoplasma gondii. (United States)

    Tonin, Alexandre A; Da Silva, Aleksandro S; Ruchel, Jader B; Rezer, João F P; Camillo, Giovana; Faccio, Luciana; França, Raqueli T; Leal, Daniela B R; Duarte, Marta M M F; Vogel, Fernada F; de la Rue, Mario L; Lopes, Sonia T A


    An investigation of E-NTPDase and E-ADA activities in lymphocytes from rats experimentally infected with Toxoplasma gondii was carried out in this study. For this purpose, twenty four adult male Wistar rats were divided in two groups/four subgroups (A1 and A2; B1 and B2-6 animal/each group), with "A" as uninfected and "B" inoculated with T. gondii (RH strain). Sampling was performed on days 5 and 10 post-infection (p.i.), with evaluation of hemogram, immunoglobulins (IgM and IgG) and activity of E-NTPDase and E-ADA in lymphocytes. Enzymes essays showed ATP hydrolysis increased on days 5 (PADA activity on lymphocytes was also increased in both evaluated periods (PADA increased activities observed on lymphocytes, it is possible to suggest their involvement in an anti-inflammatory response, consisting of a modulatory response, preventing excessive tissue damage caused by the infection with Toxoplasma gondii. Copyright © 2013 Elsevier Inc. All rights reserved.


    Directory of Open Access Journals (Sweden)

    R. R. Khasanova


    Full Text Available Evaluation of proliferative and IL-2-producing activity of peripheral blood lymphocytes wasperformed, using cultural methods, in patients with drug-sensitive and drug-resistant infiltrative pulmonary tuberculosis. The cell testing was performed at basal level and following in vitro stimulation with recombinant IL-2 and M. tuberculosis antigens. It was established that clinical course of infiltrative pulmonary tuberculosis, independently on drug sensitivity/resistance of the infectious pathogen, is accompanied by suppression of spontaneous lymphoproliferation. The levels of induced IL-2 production in drug-sensitive tuberculosis proved to be increased, whereas a reserve of IL-2-secreting reactivity of blood lymphocytes was lower than in drugresistant infection. Also, it was revealed that the level of lymphoproliferative response induced by IL-2, does not depend on clinical variant of tuberculosis, whereas stimulation of IL-2 production in blood lymphocytes is attained only in cases of drug-resistant tuberculosis variant.

  8. Decreased lymphocyte dopamine transporter in romantic lovers. (United States)

    Marazziti, Donatella; Baroni, Stefano; Giannaccini, Gino; Piccinni, Armando; Mucci, Federico; Catena-Dell'Osso, Mario; Rutigliano, Grazia; Massimetti, Gabriele; Dell'Osso, Liliana


    The role of dopamine (DA) in romantic love is suggested by different evidence and is supported by the findings of some brain imaging studies. The DA transporter (DAT) is a key structure in regulating the concentration of the neurotransmitter in the synaptic cleft. Given the presence of DAT in blood cells, the present study aimed to explore it in resting lymphocytes of 30 healthy subjects of both sexes in the early stage of romantic love (no longer than 6 months), as compared with 30 subjects involved in a long-lasting relationship. All subjects had no physical or psychiatric illness. The DAT was measured by means of the [3H]-WIN 35,428 binding and the [3H]-DA reuptake to resting lymphocytes membranes. Romantic love was assessed by a specific questionnaire developed by us. The results showed that the subjects in the early phase of romantic love had a global alteration of the lymphocyte DAT involving both a decreased number of proteins (Bmax) and a reduced functionality (Vmax). Taken together, these findings would indicate the presence of increased levels of DA in romantic love that, if paralleled by similar concentrations in the brain, would explain some peculiar features of this human feeling.

  9. Radiosensitivity of human lymphocytes and thymocytes

    International Nuclear Information System (INIS)

    Kwan, D.K.; Norman, A.


    The in vitro survival of human peripheral blood lymphocytes and thymocytes was measured 4 days following graded doses of γ radiation. Results indicate considerable heterogeneity among lymphocyte subpopulations with respect to radiosensitivity. Total T lymphocytes were characterized by rosette formation with neuraminidase-treated sheep red blood cells (nSRBC); early T (T/sub E/) cells, by early rosettes; and B cells, by their inability to form nSRBC rosettes. Late T (T/sub L/) cells were defined as T -- T/sub E/. Survival curves of T, T/sub E/, and B cells are biphasic. The radiosensitive and radioresistant components of T, T/sub E/, and B cells all have a D 0 of about 50 and 550 rad, respectively. B cells appeared to be slightly more radiosensitive than T cells. T/sub L/ cells and thymocytes, however, appeared to be homogeneous with respect to radiosensitivity, both having D 0 values of about 135 rad. The survival of T cells in mixed T and B cell cultures resembled that of separated T cells, suggesting that ionizing radiation has no significant effect on rosette formation. It also indicates that interactions of T and B cells do not significantly affect their radiation responses

  10. Robot system for preparing lymphocyte chromosome

    International Nuclear Information System (INIS)

    Hayata, Isamu; Furukawa, Akira; Yamamoto, Mikio; Sato, Koki; Tabuchi, Hiroyoshi; Okabe, Nobuo.


    Towards the automatization of the scoring of chromosome aberrations in radiation dosimetry with the emphasis on the improvement of biological preparations, the conventional culture and harvesting method was modified. Based on this modified method, a culture and harvest robotic system (CHROSY) for preparing lymphocyte chromosome was developed. The targeted points of the modification are as in the preparing lymphocyte chromosome was developed. The targeted points of the modification are as in the following. 1) Starting culture with purified lymphocytes in a fixed cell number. 2) Avoiding the loss of cells in changing the liquids following centrifugalization. 3) Keeping the quantity of the liquids to be applied to the treatments of cells fixed. 4) Building a system even a beginner can handle. System features are as follows. 1) Operation system: Handling robot having 5 degrees of freedom; a rotator incubator with an automatic sliding door; units for setting and removing pipette tips; a centrifuge equipped with a position adjuster and an automatic sliding door; two aluminium block baths; two nozzles as pipettes and aspirators connected to air pumps; a capping unit with a nozzle for CO 2 gas; a compressor; and an air manipulated syringe. 2) Control system; NEC PC-9801RX21 with CRT; and program written in Basic and Assembly languages on MS-DOS. It took this system 2 hours and 25 minutes to harvest 2 cultures. A fairly good chromosome slide was made from the sample harvested by CHROSY automatically. (author)

  11. Lymphocytic hypophysitis masquerading as pituitary adenoma

    Directory of Open Access Journals (Sweden)

    Rajneesh Mittal


    Full Text Available Introduction: Pituitary hypophysitis (PH is characterized by pituitary infiltration of lymphocytes, macrophages, and plasma cells that could lead to loss of pituitary function. Hypophysitis may be autoimmune or secondary to systemic diseases or infections. Based on the histopathological findings PH is classified into lymphocytic, granulomatous, xanthomatous, mixed forms (lymphogranulomatous, xanthogranulomatous, necrotizing and Immunoglobulin- G4 (IgG4 plasmacytic types. Objective: To report a case of lymphocytic hypophysitis (LH. Case Report: A 15-year-old girl presented with history of headache, amenorrhea, and history of polyuria for past 4 months. Initial evaluation had suppressed follicular stimulating hormone (<0.01 mIU/ml, high prolactin levels (110.85 ng/ml and diabetes insipidus (DI. Magnetic resonance imaging of sella was suggestive of pituitary macroadenoma with partial compression over optic chiasma. Patient underwent surgical decompression. Yellowish firm tissue was evacuated and xanthochromic fluid was aspirated. Histopathology was suggestive of LH. She resumed her cycles postoperatively after 4 months, prolactin levels normalized, however, she continues to have DI and is on desmopressin spray. This case has been presented here for its rare presentation in an adolescent girl because it is mostly seen in young females and postpartum period and its unique presentation as an expanding pituitary mass with optic chiasma compression. Conclusion: Definitive diagnosis of LH is based on histopathological evaluation. Therapeutic approach should be based on the grade of suspicion and clinical manifestations of LH.

  12. Normal lymphocyte immunophenotype in an elderly population

    Directory of Open Access Journals (Sweden)

    Sâmia Macedo Queiroz Mota Castellão Tavares


    Full Text Available OBJECTIVE: The aim of this work was to evaluate the lymphocyte immunophenotype in an elderly population.METHODS: This study enrolled 35 over 60-year-old volunteers and a control group composed of 35 young adults. The study included elderly without diseases that might affect the functioning of the immune system. These individuals were consulted by doctors and after a physical examination, laboratory tests were performed using a Beckman Coulter (r flow cytometer. The GraphPad Prism computer program was employed for statistical analysis with the level of significance being set for p-values <0.05.RESULTS: There is a statistically significant reduction in the number of lymphocytes (CD8 +, CD2 + and CD3 + cells in the elderly compared to young adults. These low rates are explained by changes attributed to aging and may be partly responsible for the reduction in the cellular immune response, lower proliferative activity and the low cytotoxicity of lymphocytes.CONCLUSION: These parameters showed greater impairment of adaptive immunity in the elderly population and can therefore explain the greater fragility of the aged body to developing diseases.

  13. 31P magnetization transfer measurements of Pi→ATP flux in exercising human muscle. (United States)

    Sleigh, Alison; Savage, David B; Williams, Guy B; Porter, David; Carpenter, T Adrian; Brindle, Kevin M; Kemp, Graham J


    Fundamental criticisms have been made over the use of (31)P magnetic resonance spectroscopy (MRS) magnetization transfer estimates of inorganic phosphate (Pi)→ATP flux (VPi-ATP) in human resting skeletal muscle for assessing mitochondrial function. Although the discrepancy in the magnitude of VPi-ATP is now acknowledged, little is known about its metabolic determinants. Here we use a novel protocol to measure VPi-ATP in human exercising muscle for the first time. Steady-state VPi-ATP was measured at rest and over a range of exercise intensities and compared with suprabasal oxidative ATP synthesis rates estimated from the initial rates of postexercise phosphocreatine resynthesis (VATP). We define a surplus Pi→ATP flux as the difference between VPi-ATP and VATP. The coupled reactions catalyzed by the glycolytic enzymes GAPDH and phosphoglycerate kinase (PGK) have been shown to catalyze measurable exchange between ATP and Pi in some systems and have been suggested to be responsible for this surplus flux. Surplus VPi-ATP did not change between rest and exercise, even though the concentrations of Pi and ADP, which are substrates for GAPDH and PGK, respectively, increased as expected. However, involvement of these enzymes is suggested by correlations between absolute and surplus Pi→ATP flux, both at rest and during exercise, and the intensity of the phosphomonoester peak in the (31)P NMR spectrum. This peak includes contributions from sugar phosphates in the glycolytic pathway, and changes in its intensity may indicate changes in downstream glycolytic intermediates, including 3-phosphoglycerate, which has been shown to influence the exchange between ATP and Pi catalyzed by GAPDH and PGK. Copyright © 2016 the American Physiological Society.

  14. A new function for ATP: activating cardiac sympathetic afferents during myocardial ischemia. (United States)

    Fu, Liang-Wu; Longhurst, John C


    Myocardial ischemia activates cardiac sympathetic afferents leading to chest pain and reflex cardiovascular responses. Brief myocardial ischemia leads to ATP release in the interstitial space. Furthermore, exogenous ATP and α,β-methylene ATP (α,β-meATP), a P2X receptor agonist, stimulate cutaneous group III and IV sensory nerve fibers. The present study tested the hypothesis that endogenous ATP excites cardiac afferents during ischemia through activation of P2 receptors. Nerve activity of single unit cardiac sympathetic afferents was recorded from the left sympathetic chain or rami communicates (T(2)-T(5)) in anesthetized cats. Single fields of 45 afferents (conduction velocities = 0.25-4.92 m/s) were identified in the left ventricle with a stimulating electrode. Five minutes of myocardial ischemia stimulated 39 of 45 cardiac afferents (8 Aδ, 37 C fibers). Epicardial application of ATP (1-4 μmol) stimulated six ischemically sensitive cardiac afferents in a dose-dependent manner. Additionally, epicardial ATP (2 μmol), ADP (2 μmol), a P2Y agonist, and α,β-meATP (0.5 μmol) significantly activated eight other ischemically sensitive afferents. Third, pyridoxal phosphate-6-azophenyl-2',4'-disulfonic acid, a P2 receptor antagonist, abolished the responses of six afferents to epicardial ATP (2 μmol) and attenuated the ischemia-related increase in activity of seven other afferents by 37%. In the absence of P2 receptor blockade, cardiac afferents responded consistently to repeated application of ATP (n = 6) and to recurrent myocardial ischemia (n = 6). Finally, six ischemia-insensitive cardiac spinal afferents did not respond to epicardial ATP (2-4 μmol), although these afferents did respond to epicardial bradykinin. Taken together, these data indicate that, during ischemia, endogenously released ATP activates ischemia-sensitive, but not ischemia-insensitive, cardiac spinal afferents through stimulation of P2 receptors likely located on the cardiac sensory

  15. Local Content

    CSIR Research Space (South Africa)

    Gibberd, Jeremy


    Full Text Available Local content refers to materials and products made in a country as opposed those that are imported. There is an increasing interest in the concept of local content as a means of supporting local economies and providing jobs (Belderbos & Sleuwaegen...

  16. Role of connexin 32 hemichannels in the release of ATP from peripheral nerves. (United States)

    Nualart-Marti, Anna; del Molino, Ezequiel Mas; Grandes, Xènia; Bahima, Laia; Martin-Satué, Mireia; Puchal, Rafel; Fasciani, Ilaria; González-Nieto, Daniel; Ziganshin, Bulat; Llobet, Artur; Barrio, Luis C; Solsona, Carles


    Extracellular purines elicit strong signals in the nervous system. Adenosine-5'-triphosphate (ATP) does not spontaneously cross the plasma membrane, and nervous cells secrete ATP by exocytosis or through plasma membrane proteins such as connexin hemichannels. Using a combination of imaging, luminescence and electrophysiological techniques, we explored the possibility that Connexin 32 (Cx32), expressed in Schwann cells (SCs) myelinating the peripheral nervous system could be an important source of ATP in peripheral nerves. We triggered the release of ATP in vivo from mice sciatic nerves by electrical stimulation and from cultured SCs by high extracellular potassium concentration-evoked depolarization. No ATP was detected in the extracellular media after treatment of the sciatic nerve with Octanol or Carbenoxolone, and ATP release was significantly inhibited after silencing Cx32 from SCs cultures. We investigated the permeability of Cx32 to ATP by expressing Cx32 hemichannels in Xenopus laevis oocytes. We found that ATP release is coupled to the inward tail current generated after the activation of Cx32 hemichannels by depolarization pulses, and it is sensitive to low extracellular calcium concentrations. Moreover, we found altered ATP release in mutated Cx32 hemichannels related to the X-linked form of Charcot-Marie-Tooth disease, suggesting that purinergic-mediated signaling in peripheral nerves could underlie the physiopathology of this neuropathy. Copyright © 2013 Wiley Periodicals, Inc.

  17. An ATP sensitive light addressable biosensor for extracellular monitoring of single taste receptor cell. (United States)

    Wu, Chunsheng; Du, Liping; Zou, Ling; Zhao, Luhang; Wang, Ping


    Adenosine triphosphate (ATP) is considered as the key neurotransmitter in taste buds for taste signal transmission and processing. Measurements of ATP secreted from single taste receptor cell (TRC) with high sensitivity and specificity are essential for investigating mechanisms underlying taste cell-to-cell communications. In this study, we presented an aptamer-based biosensor for the detection of ATP locally secreted from single TRC. ATP sensitive DNA aptamer was used as recognition element and its DNA competitor was served as signal transduction element that was covalently immobilized on the surface of light addressable potentiometric sensor (LAPS). Due to the light addressable capability of LAPS, local ATP secretion from single TRC can be detected by monitoring the working potential shifts of LAPS. The results show this biosensor can detect ATP with high sensitivity and specificity. It is demonstrated this biosensor can effectively detect the local ATP secretion from single TRC responding to tastant mixture. This biosensor could provide a promising new tool for the research of taste cell-to-cell communications as well as for the detection of local ATP secretion from other types of ATP secreting individual cells.

  18. Multiscale approach to link red blood cell dynamics, shear viscosity, and ATP release. (United States)

    Forsyth, Alison M; Wan, Jiandi; Owrutsky, Philip D; Abkarian, Manouk; Stone, Howard A


    RBCs are known to release ATP, which acts as a signaling molecule to cause dilation of blood vessels. A reduction in the release of ATP from RBCs has been linked to diseases such as type II diabetes and cystic fibrosis. Furthermore, reduced deformation of RBCs has been correlated with myocardial infarction and coronary heart disease. Because ATP release has been linked to cell deformation, we undertook a multiscale approach to understand the links between single RBC dynamics, ATP release, and macroscopic viscosity all at physiological shear rates. Our experimental approach included microfluidics, ATP measurements using a bioluminescent reaction, and rheology. Using microfluidics technology with high-speed imaging, we visualize the deformation and dynamics of single cells, which are known to undergo motions such as tumbling, swinging, tanktreading, and deformation. We report that shear thinning is not due to cellular deformation as previously believed, but rather it is due to the tumbling-to-tanktreading transition. In addition, our results indicate that ATP release is constant at shear stresses below a threshold (3 Pa), whereas above the threshold ATP release is increased and accompanied by large cellular deformations. Finally, performing experiments with well-known inhibitors, we show that the Pannexin 1 hemichannel is the main avenue for ATP release both above and below the threshold, whereas, the cystic fibrosis transmembrane conductance regulator only contributes to deformation-dependent ATP release above the stress threshold.

  19. Identification of a new Mpl-interacting protein, Atp5d. (United States)

    Liu, Hongyan; Zhao, Zhenhu; Zhong, Yuxu; Shan, Yajun; Sun, Xiaohong; Mao, Bingzhi; Cong, Yuwen


    Thrombopoietin (TPO) can regulate hematopoiesis and megakaryopoiesis via activation of its receptor, c-Mpl, and multiple downstream signal transduction pathways. Using the cytoplasmic domain of Mpl as bait, we performed yeast two-hybrid screening, and found that the protein Atp5d might associate with Mpl. Atp5d is known as the δ subunit of mitochondrial ATP synthase, but little is known about the function of dissociative Atp5d. The interaction between Mpl and Atp5d was confirmed by the yeast two-hybrid system, mammalian two-hybrid assay, pull-down experiment, and co-immunoprecipitation study in vivo and in vitro. An additional immunofluorescence assay showed that the two proteins can colocalize along the plasma membrane in the cytoplasm. Using the yeast two-hybrid system, we tested a series of cytoplasmic truncated mutations for their ability to bind Atp5d and found an association between Atp5d and the Aa98-113 domain of Mpl. The dissociation of Atp5d from Mpl after TPO stimulation suggests that Atp5d may be a new component of TPO signaling.

  20. ATP-containing vesicles in stria vascular marginal cell cytoplasms in neonatal rat cochlea are lysosomes. (United States)

    Liu, Jun; Liu, Wenjing; Yang, Jun


    We confirmed that ATP is released from cochlear marginal cells in the stria vascular but the cell organelle in which ATP stores was not identified until now. Thus, we studied the ATP-containing cell organelles and suggest that these are lysosomes. Primary cultures of marginal cells of Sprague-Dawley rats aged 1-3 days was established. Vesicles within marginal cells stained with markers were identified under confocal laser scanning microscope and transmission electron microscope (TEM). Then ATP release from marginal cells was measured after glycyl-L-phenylalanine-ß- naphthylamide (GPN) treatment using a bioluminescent assay. Quinacrine-stained granules within marginal cells were labeled with LysoTracker, a lysosome tracer, and lysosomal-associated membrane protein 1(LAMP1), but not labeled with the mitochondrial tracer MitoTracker. Furthermore, LysoTracker-labelled puncta showed accumulation of Mant-ATP, an ATP analog. Treatment with 200 μM GPN quenched fluorescently labeled puncta after incubation with LysoTracker or quinacrine, but not MitoTracker. Quinacrine-labeled organelles observed by TEM were lysosomes, and an average 27.7 percent increase in ATP luminescence was observed in marginal cells extracellular fluid after GPN treatment. ATP-containing vesicles in cochlear marginal cells of the stria vascular from neonatal rats are likely lysosomes. ATP release from marginal cells may be via Ca(2+)-dependent lysosomal exocytosis.

  1. Towards the development of an automated ATP measuring platform to monitor microbial quality of drinking water

    DEFF Research Database (Denmark)

    Tatari, Karolina; Hansen, C. B.; Rasmussen, A.

    is detected by a photomultiplier. Temperature in the assay box is controlled and set to 25°C. Calibration of the system using ATP standard solutions was successful, both for free and for total ATP. Chemical release of ATP by reagent addition however resulted in the formation of particles that ultimately......This work aimed to develop an automated and nearly on-line method to monitor ATP levels in drinking water as an indicator of microbial contamination. The system consists of a microfluidic cartridge installed in a light tight box, where the sample is mixed with the reagents and the emitted light...

  2. Pharmacological and molecular comparison of K(ATP) channels in rat basilar and middle cerebral arteries

    DEFF Research Database (Denmark)

    Ploug, Kenneth Beri; Edvinsson, Lars; Olesen, Jes


    , we studied the possible involvement of endothelial K(ATP) channels by pressurized arteriography after luminal administration of synthetic K(ATP) channel openers to rat basilar and middle cerebral arteries. Furthermore, we examined the mRNA and protein expression profile of K(ATP) channels to rat...... basilar and middle cerebral arteries using quantitative real-time PCR (Polymerase Chain Reaction) and Western blotting, respectively. In the perfusion system, we found no significant responses after luminal application of three K(ATP) channel openers to rat basilar and middle cerebral arteries...

  3. Extracellular ATP acts as a damage associated molecular pattern (DAMP signal in plants

    Directory of Open Access Journals (Sweden)

    Kiwamu eTanaka


    Full Text Available As sessile organisms, plants have evolved effective mechanisms to protect themselves from environmental stresses. Damaged (i.e., wounded plants recognize a variety of endogenous molecules as danger signals, referred to as damage-associated molecular patterns (DAMPs. ATP is among the molecules that are released by cell damage, and recent evidence suggests that ATP can serve as a DAMP. Although little studied in plants, extracellular ATP is well known for its signaling role in animals, including acting as a DAMP during the inflammatory response and wound healing. If ATP acts outside the cell, then it is reasonable to expect that it is recognized by a plasma membrane-localized receptor. Recently, DORN1, a lectin receptor kinase, was shown to recognize extracellular ATP in Arabidopsis. DORN1 is the founding member of a new purinoceptor subfamily, P2K (P2 receptor Kinase, which is plant-specific. P2K1 (DORN1 is required for ATP-induced cellular responses (e.g., cytosolic Ca2+ elevation, MAPK phosphorylation, and gene expression. Genetic analysis of loss-of-function mutants and overexpression lines showed that P2K1 participates in the plant wound response, consistent with the role of ATP as a DAMP. In this review, we summarize past research on the roles and mechanisms of extracellular ATP signaling in plants, and discuss the direction of the future research of extracellular ATP as a DAMP signal.

  4. Allograft immunity in vitro. I. Cultivation conditions and mixed lymphocyte interaction of mouse peripheral lymphocytes (United States)

    Häyry, P.; Defendi, V.


    We have adapted mouse peripheral lymphocytes to culture as a preliminary step in designing a model for the study of allograft immunity in vitro. The isolation of peripheral leucocytes is facilitated by using Plasmagel® as an erythrocyte-agglutinating agent. The yield of leucocytes can be considerably increased by intravenous injection of the donor animals with supernatant fluid from Bordetella pertussis cultures and the lymphocytes thus mobilized react both to phytohaemagglutinin (PHA) and allogeneic stimulus, as do lymphocytes from untreated animals. Preparations which contain more than 25–50 RBC/WBC are refractory in the mixed lymphocyte interaction (MLI). The optimum cell density for the proliferative response is approximately 1–3 × 106 lymphocytes/ml. Various nutritive milieu were tested and found to have little influence on the MLI; both normal and suspension media behaved in a similar manner. PHA causes a vigorous proliferative response in mouse peripheral lymphocytes, the 3H–TdR incorporation values in PHA-containing cultures at peak point of stimulation (3rd day) being up to 1000 times those observed for control cultures. The allogeneic response in the MLI takes place later (6th to 7th day) and is weaker, about one-tenth the PHA response, when strains differing at the H-2 locus are used as cell donors. Because the specific proliferative response to allogeneic stimulus in mixed culture, regardless of the way it is measured, is indistinguishable from the response produced by other non-specific factors, these other factors must be critically excluded. It appears that supplementing the culture medium with low concentrations of certain lots of foetal calf or agamma-newborn-calf serum permits the study of the specific response at an optimum sensitivity. PMID:4315207

  5. Red blood cell dynamics: from cell deformation to ATP release. (United States)

    Wan, Jiandi; Forsyth, Alison M; Stone, Howard A


    The mechanisms of red blood cell (RBC) deformation under both static and dynamic, i.e., flow, conditions have been studied extensively since the mid 1960s. Deformation-induced biochemical reactions and possible signaling in RBCs, however, were proposed only fifteen years ago. Therefore, the fundamental relationship between RBC deformation and cellular signaling dynamics i.e., mechanotransduction, remains incompletely understood. Quantitative understanding of the mechanotransductive pathways in RBCs requires integrative studies of physical models of RBC deformation and cellular biochemical reactions. In this article we review the physical models of RBC deformation, spanning from continuum membrane mechanics to cellular skeleton dynamics under both static and flow conditions, and elaborate the mechanistic links involved in deformation-induced ATP release. This journal is © The Royal Society of Chemistry 2011

  6. Splice Site Mutations in the ATP7A Gene

    DEFF Research Database (Denmark)

    Skjørringe, Tina; Tümer, Zeynep; Møller, Lisbeth Birk


    Menkes disease (MD) is caused by mutations in the ATP7A gene. We describe 33 novel splice site mutations detected in patients with MD or the milder phenotypic form, Occipital Horn Syndrome. We review these 33 mutations together with 28 previously published splice site mutations. We investigate 12...... mutations for their effect on the mRNA transcript in vivo. Transcriptional data from another 16 mutations were collected from the literature. The theoretical consequences of splice site mutations, predicted with the bioinformatics tool Human Splice Finder, were investigated and evaluated in relation...... to in vivo results. Ninety-six percent of the mutations identified in 45 patients with classical MD were predicted to have a significant effect on splicing, which concurs with the absence of any detectable wild-type transcript in all 19 patients investigated in vivo. Sixty-seven percent of the mutations...

  7. Mesurements of intracellular ATP provide new insight into the regulation of glycolysis in the yeast Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Ytting, Cecilie Karkov; Fuglsang, Anja Thoe; Hiltunen, J. Kalervo


    Glycolysis in the yeast Saccharomyces cerevisiae exhibits temporal oscillation under anaerobic or semianaerobic conditions. Previous evidence indicated that at least two membrane-bound ATPases, the mitochondrial F0F1 ATPase and the plasma membrane P-type ATPase (Pma1p), were important in regulating...... of the temporal behaviour of intracellular ATP in a yeast strain with oscillating glycolysis showed that, in addition to oscillation in intracellular ATP, there is an overall slow decrease in intracellular ATP because the ATP consumption rate exceeds the ATP production in glycolysis. Measurements of the temporal...... activity is under strict control. In the absence of glucose ATPase activity is switched off, and the intracellular ATP concentration is high. When glucose is added to the cells the ATP concentration starts to decrease, because ATP consumption exceeds ATP production by glycolysis. Finally, when glucose...

  8. Visualization and measurement of ATP levels in living cells replicating hepatitis C virus genome RNA.

    Directory of Open Access Journals (Sweden)

    Tomomi Ando

    Full Text Available Adenosine 5'-triphosphate (ATP is the primary energy currency of all living organisms and participates in a variety of cellular processes. Although ATP requirements during viral lifecycles have been examined in a number of studies, a method by which ATP production can be monitored in real-time, and by which ATP can be quantified in individual cells and subcellular compartments, is lacking, thereby hindering studies aimed at elucidating the precise mechanisms by which viral replication energized by ATP is controlled. In this study, we investigated the fluctuation and distribution of ATP in cells during RNA replication of the hepatitis C virus (HCV, a member of the Flaviviridae family. We demonstrated that cells involved in viral RNA replication actively consumed ATP, thereby reducing cytoplasmic ATP levels. Subsequently, a method to measure ATP levels at putative subcellular sites of HCV RNA replication in living cells was developed by introducing a recently-established Förster resonance energy transfer (FRET-based ATP indicator, called ATeam, into the NS5A coding region of the HCV replicon. Using this method, we were able to observe the formation of ATP-enriched dot-like structures, which co-localize with non-structural viral proteins, within the cytoplasm of HCV-replicating cells but not in non-replicating cells. The obtained FRET signals allowed us to estimate ATP concentrations within HCV replicating cells as ∼5 mM at possible replicating sites and ∼1 mM at peripheral sites that did not appear to be involved in HCV replication. In contrast, cytoplasmic ATP levels in non-replicating Huh-7 cells were estimated as ∼2 mM. To our knowledge, this is the first study to demonstrate changes in ATP concentration within cells during replication of the HCV genome and increased ATP levels at distinct sites within replicating cells. ATeam may be a powerful tool for the study of energy metabolism during replication of the viral genome.

  9. Single K ATP channel opening in response to action potential firing in mouse dentate granule neurons. (United States)

    Tanner, Geoffrey R; Lutas, Andrew; Martínez-François, Juan Ramón; Yellen, Gary


    ATP-sensitive potassium channels (K(ATP) channels) are important sensors of cellular metabolic state that link metabolism and excitability in neuroendocrine cells, but their role in nonglucosensing central neurons is less well understood. To examine a possible role for K(ATP) channels in modulating excitability in hippocampal circuits, we recorded the activity of single K(ATP) channels in cell-attached patches of granule cells in the mouse dentate gyrus during bursts of action potentials generated by antidromic stimulation of the mossy fibers. Ensemble averages of the open probability (p(open)) of single K(ATP) channels over repeated trials of stimulated spike activity showed a transient increase in p(open) in response to action potential firing. Channel currents were identified as K(ATP) channels through blockade with glibenclamide and by comparison with recordings from Kir6.2 knock-out mice. The transient elevation in K(ATP) p(open) may arise from submembrane ATP depletion by the Na(+)-K(+) ATPase, as the pump blocker strophanthidin reduced the magnitude of the elevation. Both the steady-state and stimulus-elevated p(open) of the recorded channels were higher in the presence of the ketone body R-β-hydroxybutyrate, consistent with earlier findings that ketone bodies can affect K(ATP) activity. Using perforated-patch recording, we also found that K(ATP) channels contribute to the slow afterhyperpolarization following an evoked burst of action potentials. We propose that activity-dependent opening of K(ATP) channels may help granule cells act as a seizure gate in the hippocampus and that ketone-body-mediated augmentation of the activity-dependent opening could in part explain the effect of the ketogenic diet in reducing epileptic seizures.

  10. Tomatidine Is a Lead Antibiotic Molecule That Targets Staphylococcus aureus ATP Synthase Subunit C. (United States)

    Lamontagne Boulet, Maxime; Isabelle, Charles; Guay, Isabelle; Brouillette, Eric; Langlois, Jean-Philippe; Jacques, Pierre-Étienne; Rodrigue, Sébastien; Brzezinski, Ryszard; Beauregard, Pascale B; Bouarab, Kamal; Boyapelly, Kumaraswamy; Boudreault, Pierre-Luc; Marsault, Éric; Malouin, François


    Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of deadly hospital-acquired infections. The discovery of anti- Staphylococcus antibiotics and new classes of drugs not susceptible to the mechanisms of resistance shared among bacteria is imperative. We recently showed that tomatidine (TO), a steroidal alkaloid from solanaceous plants, possesses potent antibacterial activity against S. aureus small-colony variants (SCVs), the notoriously persistent form of this bacterium that has been associated with recurrence of infections. Here, using genomic analysis of in vitro -generated TO-resistant S. aureus strains to identify mutations in genes involved in resistance, we identified the bacterial ATP synthase as the cellular target. Sequence alignments were performed to highlight the modified sequences, and the structural consequences of the mutations were evaluated in structural models. Overexpression of the atpE gene in S. aureus SCVs or introducing the mutation found in the atpE gene of one of the high-level TO-resistant S. aureus mutants into the Bacillus subtilis atpE gene provided resistance to TO and further validated the identity of the cellular target. FC04-100, a TO derivative which also possesses activity against non-SCV strains, prevents high-level resistance development in prototypic strains and limits the level of resistance observed in SCVs. An ATP synthesis assay allowed the observation of a correlation between antibiotic potency and ATP synthase inhibition. The selectivity index (inhibition of ATP production by mitochondria versus that of bacterial ATP synthase) is estimated to be >10 5 -fold for FC04-100. Copyright © 2018 American Society for Microbiology.

  11. The danger signal extracellular ATP is an inducer of Fusobacterium nucleatum biofilm dispersal

    Directory of Open Access Journals (Sweden)

    Qinfeng Ding


    Full Text Available Plaque biofilm is the primary etiological agent of periodontal disease. Biofilm formation progresses through multiple developmental stages beginning with bacterial attachment to a surface, followed by development of microcolonies and finally detachment and dispersal from a mature biofilm as free planktonic bacteria. Tissue damage arising from inflammatory response to biofilm is one of the hallmark features of periodontal disease. A consequence of tissue damage is the release of ATP from within the cell into the extracellular space. Extracellular ATP (eATP is an example of a danger associated molecular pattern (DAMP employed by mammalian cells to elicit inflammatory and damage healing responses. Although the roles of eATP as a signaling molecule in multi-cellular organisms have been relatively well studied, exogenous ATP also influences bacteria biofilm formation. Since plaque biofilms are continuously exposed to various stresses including exposure to the host damage factors eATP, we hypothesized that eATP, in addition to eliciting inflammation could potentially influence the biofilm lifecycle of periodontal associated bacteria. We found that eATP rather than nutritional factors or oxidative stress induced dispersal of Fusobacterium nucleatum, an organism associated with periodontal disease. eATP induced biofilm dispersal through chelating metal ions present in biofilm. Dispersed F. nucleatum biofilm, regardless of natural or induced dispersal by exogenous ATP, were significantly more adhesive and invasive compared to planktonic or biofilm counterparts, and correspondingly activated significantly more pro-inflammatory cytokine production in infected periodontal fibroblasts. Dispersed F. nucleatum also exhibited significantly higher expression of fadA, a virulence factor implicated in adhesion and invasion, compared to planktonic or biofilm bacteria. This study revealed for the first time that periodontal bacterium is capable of co-opting eATP, a

  12. The effects of low dose radiation (LDR) on lymphocytes

    International Nuclear Information System (INIS)

    Su Liaoyuan; Du Zeji; Tian Hailin; Zhao Yujie; Zou Huawei; Zhou Jianhua; Kong Xiangrong; Zhang Jianhua; Shen Wei


    LDR could stimulate lymphocyte transformation for adults, children and infants. The effect of LDR on lymphocytes in malnourished children was lower, but higher on lymphocytes in cord blood. The effect of LDR on CD 4 + cells in adult persons was higher than that on CD + cells. NK cells were radioresistant. The stimulative effect of LDR on NK activity in tumor patients was lower than that in normal individuals. For the mice with tumors, LDR could increase the ratio of L 3 T 4 cells in blood, spleen and the number of cytotoxic T cells in the tumors. Extracellular fluid of the lymphocytes operated by LDR could also stimulate the lymphocyte transformation. The preliminary LDR could decrease the injuries to macromolecules, membrane antigens and chromosomes in lymphocytes which were induced by high dose radiation. The LDR- induced protein might be found from mouse spleen cells, and this protein could increase immune function in human and animals

  13. Effect of radiotherapy on lymphocyte cytotoxicity in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Wasserman, J; Melen, B [Central Microbiological Laboratory, Stockholm County Council (Sweden); Blomgren, H; Glas, U; Perlmann, P


    The cytotoxic functions of highly purified blood lymphocytes from patients with breast cancer were studied before and after radiotherapy. Addition of PHA or of rabbit antibodies to target cells (chicken erythrocytes) were chosen as two means of inducing lymphocyte cytotoxicity in vitro. The proportion of T and non-T lymphocytes was determined by means of E and EAC rosette tests. The antibody-induced cytotoxicity of lymphocytes decreased following radiotherapy while that mediated by PHA remained unchanged. There was some reduction in the percentage of EAC rosette-forming cells. These results, as well as earlier observations, suggest that the decrease in the peripheral blood of the proportion of lymphocytes with receptors for activated complement is responsible for changes in the antibody-mediated lymphocyte cytotoxicity.

  14. DNA double-strand breaks measured by pulsed-field gel electrophoresis in irradiated lymphocytes from normal humans and those with Alzheimer's disease

    International Nuclear Information System (INIS)

    Tobi, S.E.; Itzhaki, R.F.


    The authors previously found that radiation-induced chromosome aberrations (dicentrics) are more numerous in lymphocytes from Alzheimer's disease (AD) patients than in those from age-matched normal individuals (Tobi et al. 1990). They have examined double-strand breaks (dsb) produced by g amma - irradiation in the DNA of AD and normal lymphocytes by using pulsed-field gel electrophoresis. The percentage of DNA migrating into the gels is an indirect measure of the number of dsb; DNA content of sequential slices of the gel was assayed by direct fluorometry and the percentage migrating was dose dependent. Results show that the level of damage is similar in AD and normal lymphocytes and preliminary assays of the rate of repair suggest that the half-time is also similar, the value being > 1 h. The latter is consistent with the known rate of rejoining of chromosome fragments in interphase lymphocytes (Pantelias and Maillie 1985). (Author)

  15. [Mechanism of changes in the rate of glycolysis and levels of ATP and 2,3-diphosphoglycerate in human erythrocytes during aging]. (United States)

    Bogatskaia, L N; Pisaruk, A V


    Reasons which have induced changes in the glycolysis rate, ATP and 2,3-diphosphoglycerate content in human erythrocytes with ageing are studied. A fall of the hexokinase activity is shown to be one of the reasons of a significant decrease in the glycolysis rate. The total ATPase activity in erythrocytes does not change with the age. At the same time the decay rate of 2,3-diphosphoglycerate increases, that, evidently, is one of the reasons of the 2,3-diphosphoglycerate content decrease in erythrocytes with ageing.

  16. Natural History Study of Monoclonal B Cell Lymphocytosis (MBL), Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma (CLL/SLL), Lymphoplasmacytic Lymphoma (LPL)/Waldenstrom Macroglobulinemia (WM), and Splenic Marginal Zone Lymphoma (SMZL) (United States)


    B-Cell Chronic Lymphocytic Leukemia; Monoclonal B-Cell Lymphocytosis; Lymhoma, Small Lymphocytic; Chronic Lymphocytic Leukemia; Lymphoplasmacytic Lymphoma; Waldenstrom Macroglobulinemia; Splenic Marginal Zone Lymphoma

  17. Nucleolar size in lymphocytes and haemocytes of different species

    Directory of Open Access Journals (Sweden)

    J Berger


    Full Text Available The number of nucleoli in a cell and nucleolar area vary according to the cell. We compared nucleoli in mammalian circulating lymphocytes and insect circulating haemocytes. An increased nucleolar coefficient correlated with a lowered nucleoli size. The smaller nucleolar size in mammalian lymphocytes indicates a lower proteosynthetic cellular activity in both mammalian lymphocytes and insect haemocytes. Moreover, in insect haemocytes, the smaller size of the nucleoli may reflect a lowered potential to transform into another cell type.

  18. Cell kinetic and radiosensitivity of PHA stimulated goat lymphocytes

    International Nuclear Information System (INIS)

    Debuyst, B.; Rosenthal, M.; Leonard, A.


    The harlequin-staining method has been used to study the cell kinetic of goat peripheral blood lymphocytes stimulated by phytohemagglutinin and to assess their radiosensitivity. At 48 h, the standardized culture time employed for human lymphocytes, 71% of the goat lymphocytes are in first mitosis, 23% are in second mitosis and 5% in third. Irradiation with 200 rads X-rays induces an average of 24,5 dicentric chromosomes per hundred cells in first mitosis [fr

  19. Influence of immunomodulators on the lymphokine secretion of irradiated lymphocytes

    International Nuclear Information System (INIS)

    Kowalczyk-Bronisz, S.H.


    Spleen lymphocytes derived from guinea pigs loose their ability to secrete lymphokines induced by Con A after treatment with irradiation (500 and 750 mC/kg). In the presence of the immunomodulators isoprinosine, levamisole and the thymosine-like factor TFX the lymphocytes are again capable of secreting lymphokines. After treatment with immunomodulators in dosages between 10 and 100 μg/ml the migration inhibition activity for macrophages and the chemotactic activity for polymorphonuclear granulocytes produced by lymphocytes were restored. (author)

  20. MRP transporters as membrane machinery in the bradykinin-inducible export of ATP. (United States)

    Zhao, Yumei; Migita, Keisuke; Sun, Jing; Katsuragi, Takeshi


    Adenosine triphosphate (ATP) plays the role of an autocrine/paracrine signal molecule in a variety of cells. So far, however, the membrane machinery in the export of intracellular ATP remains poorly understood. Activation of B2-receptor with bradykinin-induced massive release of ATP from cultured taenia coli smooth muscle cells. The evoked release of ATP was unaffected by gap junction hemichannel blockers, such as 18alpha-glycyrrhetinic acid and Gap 26. Furthermore, the cystic fibrosis transmembrane regulator (CFTR) coupled Cl(-) channel blockers, CFTR(inh)172, 5-nitro-2-(3-phenylpropylamino)-benzoic acid, Gd3(+) and glibenclamide, failed to suppress the export of ATP by bradykinin. On the other, the evoked release of ATP was greatly reduced by multidrug resistance protein (MRP) transporter inhibitors, MK-571, indomethacin, and benzbromarone. From western blotting analysis, blots of MRP 1 protein only, but not MRP 2 and MRP 3 protein, appeared at 190 kD. However, the MRP 1 protein expression was not enhanced after loading with 1 muM bradykinin for 5 min. Likewise, niflumic acid and fulfenamic acid, Ca2(+)-activated Cl(-) channel blockers, largely abated the evoked release of ATP. The possibility that the MRP transporter system couples with Ca2(+)-activated Cl(-) channel activities is discussed here. These findings suggest that MRP transporters, probably MRP 1, unlike CFTR-Cl(-) channels and gap junction hemichannels, may contribute as membrane machinery to the export of ATP induced by G-protein-coupled receptor stimulation.

  1. Functional delineation of three groups of the ATP-dependent family of chromatin remodeling enzymes.

    NARCIS (Netherlands)

    Boyer, L.A.; Logie, C.; Bonte, E; Becker, P.B.; Wade, P.A.; Wolff, A.P.; Wu, C.; Imbalzano, A.N.; Peterson, C.L.


    ATP-dependent chromatin remodeling enzymes antagonize the inhibitory effects of chromatin. We compare six different remodeling complexes: ySWI/SNF, yRSC, hSWI/SNF, xMi-2, dCHRAC, and dNURF. We find that each complex uses similar amounts of ATP to remodel nucleosomal arrays at nearly identical rates.

  2. The P2X7 ATP receptor modulates renal cyst development in vitro

    International Nuclear Information System (INIS)

    Hillman, Kate A.; Woolf, Adrian S.; Johnson, Tanya M.; Wade, Angela; Unwin, Robert J.; Winyard, Paul J.D.


    P2X 7 , a piercing receptor, is expressed in renal collecting ducts as they undergo fulminant cysto genesis in the cpk/cpk mouse model of autosomal recessive polycystic kidney disease (ARPKD). Dissociated cpk/cpk kidneys generate cysts from cell aggregates within 24 h of suspension culture and we demonstrate that BzATP, a P2X 7 agonist, reduces cystogenesis. This effect is P2X 7 -specific, because: (i) equimolar concentrations of other purinergic agonists, ATP and UTP, had lesser effects and (ii) the P2X 7 inhibitor, oxidized ATP, abrogated the BzATP-mediated reduction in cystogenesis. BzATP did not significantly affect total cell number, proliferation, LDH release or caspase 3 activity, and zVAD-fmk, a caspase blocker, failed to modulate BzATP effects. In addition, this P2X 7 agonist did not significantly alter cyst size, probably excluding altered vectorial transport. In vivo, ATP was detected in cyst fluid from cpk/cpk kidneys; moreover, P2X 7 protein was also upregulated in human fetal ARPKD epithelia versus normal fetal collecting ducts. Thus, ATP may inhibit pathological renal cyst growth through P2X 7 signaling

  3. Inhibition of the ATP Synthase Eliminates the Intrinsic Resistance of Staphylococcus aureus towards Polymyxins

    DEFF Research Database (Denmark)

    Vestergaard, Martin; Nøhr-Meldgaard, Katrine; Bojer, Martin Saxtorph


    , linezolid, daptomycin, and oxacillin were unchanged. ATP synthase activity is known to be inhibited by oligomycin A, and the presence of this compound increased polymyxin B-mediated killing of S. aureus Our results demonstrate that the ATP synthase contributes to intrinsic resistance of S. aureus towards...

  4. Synergistic binding of glucose and aluminium ATP to hexokinase from Saccharomyces cerevisiae. (United States)

    Woolfitt, A R; Kellett, G L; Hoggett, J G


    The binding of glucose, AlATP and AlADP to the monomeric and dimeric forms of the native yeast hexokinase PII isoenzyme and to the proteolytically modified SII monomeric form was monitored at pH 6.7 by the concomitant quenching of intrinsic protein fluorescence. No fluorescence changes were observed when free enzyme was mixed with AlATP at concentrations up to 7500 microM. In the presence of saturating concentrations of glucose, the maximal quenching of fluorescence induced by AlATP was between 1.5 and 3.5% depending on species, and the average value of [L]0.5, the concentration of ligand at half-saturation, over all monomeric species was 0.9 +/- 0.4 microM. The presence of saturating concentrations of AlATP diminished [L]0.5 for glucose binding by between 260- and 670-fold for hexokinase PII and SII monomers, respectively (dependent on the ionic strength), and by almost 4000-fold for PII dimer. The data demonstrate extremely strong synergistic interactions in the binding of glucose and AlATP to yeast hexokinase, arising as a consequence of conformational changes in the free enzyme induced by glucose and in enzyme-glucose complex induced by AlATP. The synergistic interactions of glucose and AlATP are related to their kinetic synergism and to the ability of AlATP to act as a powerful inhibitor of the hexokinase reaction.

  5. The Contribution of Red Blood Cell Dynamics to Intrinsic Viscosity and Functional ATP Release (United States)

    Forsyth, Alison; Abkarian, Manouk; Wan, Jiandi; Stone, Howard


    In shear flow, red blood cells (RBCs) exhibit a variety of behaviors such as rouleaux formation, tumbling, swinging, and tank-treading. The physiological consequences of these dynamic behaviors are not understood. In vivo, ATP is known to signal vasodilation; however, to our knowledge, no one has deciphered the relevance of RBC microrheology to the functional release of ATP. Previously, we correlated RBC deformation and ATP release in microfluidic constrictions (Wan et al., 2008). In this work, a cone-plate rheometer is used to shear a low hematocrit solution of RBCs at varying viscosity ratios (λ) between the inner cytoplasmic hemoglobin and the outer medium, to determine the intrinsic viscosity of the suspension. Further, using a luciferin-luciferase enzymatic reaction, we report the relative ATP release at varying shear rates. Results indicate that for λ = 1.6, 3.8 and 11.1, ATP release is constant up to 500 s-1, which suggests that the tumbling-tanktreading transition does not alter ATP release in pure shear. For lower viscosity ratios, λ = 1.6 and 3.8, at 500 s-1 a change in slope occurs in the intrinsic viscosity data and is marked by an increase in ATP release. Based on microfluidic observations, this simultaneous change in viscosity and ATP release occurs within the tank-treading regime.

  6. Cloning and characterization of ATP synthase CF1 α gene from ...

    African Journals Online (AJOL)

    ATP synthase CF1 α subunit protein is a key enzyme for energy metabolism in plant kingdom, and plays an important role in multiple cell processes. In this study, the complete atpA gene (accession no. JN247444) was cloned from sweet potato (Ipomoea batatas L. Lam) by reverse transcriptasepolymerase chain reaction ...

  7. Tissue-specific alternative splicing and expression of ATP1B2 gene ...

    African Journals Online (AJOL)

    After heat-stress, the expression levels of the different transcripts were lower in different tissues; however, the expression of the ATP1B2-complete transcript increased in heart and lung tissues. The results of this research provide some useful information for further studies into the function of the bovine ATP1B2 gene.

  8. Determination of ATP as a fluorescence probe with europium(III)-doxycycline. (United States)

    Hou, Faju; Wang, Xiaolei; Jiang, Chongqiu


    A new spectrofluorimetric method has been developed for the determination of adenosine disodium triphosphate (ATP). We studied the interactions between the doxycycline (DC)-Eu3+ complex and adenosine disodium triphosphate (ATP) by using UV-visible absorption and fluorescence spectra. Using doxycycline (DC)-Eu3+ as a fluorescence probe, under the optimum conditions, ATP could remarkably enhance the fluorescence intensity of the DC-Eu3+ complex at lambda = 612 nm. The enhanced fluorescence intensity of the Eu3+ ion was in proportion to the concentration of ATP. The optimum conditions for the determination of ATP were also investigated. The linear ranges for ATP were 1.00 x 10(-7) - 2.00 x 10(-6) mol L(-1) with detection limits of 4.07 x 10(-8) mol L(-1). This method is simple, practical and relatively free of interference from coexisting substances, and can be successfully applied to the determination of ATP in samples. The mechanism of fluorescence enhancement between the doxycycline (DC)-Eu3+ complex and ATP was also studied.

  9. Homogeneous electrochemical aptamer-based ATP assay with signal amplification by exonuclease III assisted target recycling. (United States)

    Liu, Shufeng; Wang, Ying; Zhang, Chengxin; Lin, Ying; Li, Feng


    A novel and homogeneous electrochemical aptamer-based adenosine triphosphate (ATP) assay was demonstrated with signal amplification by exonuclease III-assisted target recycling. A superior detection limit of 1 nM toward ATP with an excellent selectivity could be achieved.

  10. Cation Transport Coupled to ATP Hydrolysis by the (Na, K)-ATPase: An Integrated, Animated Model (United States)

    Leone, Francisco A.; Furriel, Rosa P. M.; McNamara, John C.; Horisberger, Jean D.; Borin, Ivana A.


    An Adobe[R] animation is presented for use in undergraduate Biochemistry courses, illustrating the mechanism of Na[superscript +] and K[superscript +] translocation coupled to ATP hydrolysis by the (Na, K)-ATPase, a P[subscript 2c]-type ATPase, or ATP-powered ion pump that actively translocates cations across plasma membranes. The enzyme is also…

  11. Direct measurement of newly synthesized ATP dissociation kinetics in sarcoplasmic reticulum ATPase

    International Nuclear Information System (INIS)

    Teruel-Puche, J.; Kurzmack, M.; Inesi, G.


    Incubation of SR vesicles with Ca 2+ and ( 32 P)acetylphosphate, yields steady state levels of ( 32 P)phosphorylated enzyme (ATPase) intermediate and high concentrations of Ca 2+ in the lumen of the vesicles. At this time, addition of ADP (and EGTA to lower the Ca 2+ concentration in the medium outside the vesicles) results in single cycle formation of (γ- 32 P)ATP by transfer of ( 32 P)phosphate from the enzyme intermediate to ADP. The phosphoenzyme decay and ATP formation exhibit a fast component within the first 20 msec following addition of ADP, and a slower component reaching an asymptote in approximately 100 msec. They have now measured by a rapid filtration method the fraction of newly synthesized ATP which is bound to the enzyme, as opposed to the fraction dissociated into the medium. They find that nearly all the ATP formed during the initial burst is still bound to the enzyme within the initial 20 msec of reaction. Dissociation of newly synthesized ATP occurs then with approximately 13 sec -1 rate constant, permitting reequilibration of the system and further formation of ATP. The rate limiting effect of ATP dissociation and other partial reactions on the slow component of single cycle ATP synthesis is evaluated by appropriate kinetic simulations

  12. A futile cycle, formed between two ATP-dependant γ-glutamyl cycle ...

    Indian Academy of Sciences (India)

    Cystinosis, an inherited disease caused by a defect in the lysosomal cystine transporter (CTNS), is characterized by renal proximal tubular dysfunction. Adenosine triphosphate (ATP) depletion appears to be a key event in the pathophysiology of the disease, even though the manner in which ATP depletion occurs is still a ...

  13. Intestinal bile salt absorption in Atp8b1 deficient mice

    NARCIS (Netherlands)

    Groen, Annemiek; Kunne, Cindy; Paulusma, Coen C.; Kramer, Werner; Agellon, Luis B.; Bull, Laura N.; Elferink, Ronald P. J. Oude


    BACKGROUND/AIMS: Mutations in the ATP8B1 gene can cause Progressive Familial Intrahepatic Cholestasis type 1. We have previously reported that Atp8b1(G308V/G308V) mice, a model for PFIC1, have slightly, but significantly, higher baseline serum bile salt (BS) concentrations compared to wt mice. Upon

  14. Inhibition of chemokine expression in rat inflamed paws by systemic use of the antihyperalgesic oxidized ATP

    Directory of Open Access Journals (Sweden)

    Ticozzi Paolo


    Full Text Available Abstract Background We previously showed that local use of periodate oxidized ATP (oATP, a selective inhibitor of P2X7 receptors for ATP in rat paw treated with Freund's adjuvant induced a significant reduction of hyperalgesia Herein we investigate the role of oATP, in the rat paws inflamed by carrageenan, which mimics acute inflammation in humans. Results Local, oral or intravenous administration of a single dose of oATP significantly reduced thermal hyperalgesia in hind paws of rats for 24 hours, and such effect was greater than that induced by diclofenac or indomethacin. Following oATP treatment, the expression of the pro-inflammatory chemokines interferon-gamma-inducible protein-10 (IP-10, mon ocyte chemoattractant protein-1 (MCP-1 and interleukin-8 (IL-8 within the inflamed tissues markedly decreased on vessels and infiltrated cells. In parallel, the immunohistochemical findings showed an impairment, with respect to the untreated rats, in P2X7 expression, mainly on nerves and vessels close to the site of inflammation. Finally, oATP treatment significantly reduced the presence of infiltrating inflammatory macrophages in the paw tissue. Conclusion Taken together these results clearly show that oATP reduces carrageenan-induced inflammation in rats.

  15. Fungal natural products targeting chronic lymphocytic leukemia

    DEFF Research Database (Denmark)

    Bladt, Tanja Thorskov; Kildgaard, Sara; Knudsen, Peter Boldsen


    Chronic lymphocytic leukemia (CLL) is the most common leukemia in adults from the western world. No curative treatments of CLL are presently known so the treatment strategy today is primarily to prolong patient survival,1 why we have initiated new activities towards discovery of novel compounds......,3 This includes analysis of the spectroscopic data generated from LC-DAD-MS to reveal whether the active principles are either structurally known compounds or are likely to be novel compounds. This paper will illustrate our integrated discovery approaches and recent findings of anti-leukemia compounds....

  16. Lymphocytic subsets in occupationally exposed persons

    International Nuclear Information System (INIS)

    Tuschl, H.; Kovac, R.; Wottawa, A.


    The percentage of CD2, CD4, CD8 and NK cells of peripheral blood was investigated in persons occupationally exposed to very low doses of ionizing radiation. Investigations were carried out by monoclonal antibodies and flow-cytometry. While significant effects of age and smoking habits on the relative number of CD8 cells and CD4/CD8 ratios could be established, no influence of the very low radiation exposure on the profile of lymphocytic cells in blood was found, except a very slight effect on the relative number of total T cells (= CD2 cells). 7tabs., 2figs., 16refs. (Author)

  17. Ibrutinib (PCI-32765) in chronic lymphocytic leukemia. (United States)

    Jain, Nitin; O'Brien, Susan


    B-cell receptor (BCR) signaling is essential for chronic lymphocytic leukemia (CLL) cell survival. Many kinases in the BCR signaling pathway are being studied as potential therapeutic targets. Ibrutinib (PCI-32765) is a novel first-in-class selective inhibitor of Bruton tyrosine kinase. Preclinical evidence suggests that ibrutinib inhibits CLL cell survival and proliferation and affects CLL cell migration and homing. Early clinical data in patients with CLL and non-Hodgkin lymphoma is encouraging. It is likely that ibrutinib and other drugs targeting the BCR pathway will become an integral component of CLL therapy. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. DNA repair in PHA stimulated human lymphocytes

    International Nuclear Information System (INIS)

    Catena, C.; Mattoni, A.


    Damage an repair of radiation induced DNA strand breaks were measured by alkaline lysis and hydroxyapatite chromatography. PHA stimulated human lymphocytes show that the rejoining process is complete within the first 50 min., afterwords secondary DNA damage and chromatid aberration. DNA repair, in synchronized culture, allows to evaluate individual repair capacity and this in turn can contribute to the discovery of individual who, although they do not demonstrate apparent clinical signs, are carriers of DNA repair deficiency. Being evident that a correlation exists between DNA repair capacity and carcinogenesis, the possibility of evaluating the existent relationship between DNA repair and survival in tumor cells comes therefore into discussion

  19. Analysis in cytokinesis-blocked human lymphocytes

    International Nuclear Information System (INIS)

    Catena, C.; Mattoni, A.


    Biological dosimetry can be considered as an additional method to physical dosimetry for estimating dose absorption after exposure to ionizing radiation. Fully validated as well as new promising approaches in this field are reviewed. Recent experiments, carried out in our laboratory, on the analysis of micronuclei in cytokinesis-blocked human lymphocytes are presented. The possible relevance of differential human individual response to ionizing radiation, in view of the occurrence of radiosensitive syndromes, for the estimation of the absorbed dose in human is also discussed

  20. Brick mortar exposure and chronic lymphocytic leukemia. (United States)

    Markovic-Denic, L; Jankovic, S; Marinkovic, J; Radovanovic, Z


    A case-control study of 130 patients with chronic lymphocytic leukemia (CLL) and 130 controls matched with respect to sex, age (2 years), type of residence (urban-rural) and area of residence (according to the national per capita income) was carried out. Conditional logistic regression analysis showed that, apart of four risk factors already described in the literature (work in a hazardous industry, hair dye use, family history of leukemia and exposure to electromagnetic radiation), brick mortar exposure was also significantly related to CLL.

  1. Brick mortar exposure and chronic lymphocytic leukemia

    International Nuclear Information System (INIS)

    Markovic-Denic, Lj.; Jankovic, S.; Marinkovic, J.; Radovanovic, Z.


    A case-control study of 130 patients with chronic lymphocytic leukemia (CLL) and 130 controls matched with respect to sex, age (2 years), type of residence, (urban-rural) and area of residence (according to the national per capita income) was carried out. Conditional logistic regression analysis showed that, apart of four risk factors already described in the literature (work in a hazardous industry, hair dye use, family history of leukemia and exposure to electromagnetic radiation), brick mortar exposure was also significantly related to CLL. (author)

  2. Brick mortar exposure and chronic lymphocytic leukemia

    Energy Technology Data Exchange (ETDEWEB)

    Markovic-Denic, Lj; Jankovic, S [Institute of Epidemiology, Faculty of Medicine, Belgrade (Yugoslavia); Marinkovic, J [Institute of Social Medicine, Statistics and Healt Research, Faculty of Medicine, Belgrade (Yugoslavia); Radovanovic, Z [Department of Community Medicine and Behavioural Sciences, Faculty of Medicine, 13110 Safat (Kuwait)


    A case-control study of 130 patients with chronic lymphocytic leukemia (CLL) and 130 controls matched with respect to sex, age (2 years), type of residence, (urban-rural) and area of residence (according to the national per capita income) was carried out. Conditional logistic regression analysis showed that, apart of four risk factors already described in the literature (work in a hazardous industry, hair dye use, family history of leukemia and exposure to electromagnetic radiation), brick mortar exposure was also significantly related to CLL. (author) 1 tab., 30 refs.

  3. Peripheral lymphocyte subpopulations in recurrent aphthous ulceration

    DEFF Research Database (Denmark)

    Pedersen, A; Klausen, B; Hougen, H P


    Peripheral lymphocyte subsets--T-helper (CD4+), T-suppressor/cytotoxic (CD8+), and naive/virgin T cells/natural killer cells (CD45RA)--were studied quantitatively in 30 patients with recurrent aphthous ulceration (RAU) and 29 sex- and age-matched RAU-free control donors. The CD4+ percentage...... was significantly lower in the patients than in the control group (P less than 0.0001), whereas CD8+ and CD4/CD8 ratio figures did not differ significantly between patients and controls. The CD45RA+ counts were significantly higher in the patient group (P less than 0.01). The study supports previous investigations...

  4. HLA-DP related suppression of mixed lymphocyte reaction with alloactivated lymphocytes

    DEFF Research Database (Denmark)

    Ødum, Niels; Hofmann, B; Jakobsen, B K


    We studied the influence of HLA class I and class II antigens on the suppression of the MLR induced by primed lymphocytes (PLs) alloactivated in vitro. The suppression of 14 different PLs of 83 MLRs was analyzed. The PLs were primed against (i) HLA-DP (SB) (ii) HLA-DR/DQ or (iii) both HLA-DP and ...

  5. HLA-DP related suppression of mixed lymphocyte reaction with alloactivated lymphocytes

    DEFF Research Database (Denmark)

    Ødum, Niels; Hofmann, B; Jakobsen, B K


    We studied the influence of HLA class I and class II antigens on the suppression of the MLR induced by primed lymphocytes (PLs) alloactivated in vitro. The suppression of 14 different PLs of 83 MLRs was analyzed. The PLs were primed against (i) HLA-DP (SB) (ii) HLA-DR/DQ or (iii) both HLA-DP and DR...

  6. Concanavalin A-induced activation of lymphocytic choriomeningitis virus memory lymphocytes into specifically cytotoxic T cells

    DEFF Research Database (Denmark)

    Marker, O; Thomsen, Allan Randrup; Andersen, G T


    When spleen cells, which have been primed to Lymphocytic Choriomeningitis (LCM) virus during a primary infection several months previously, are stimulated in vitro with Con A. highly specific secondary cytotoxic effector cells are generated. The degree of cytotoxicity revealed by such Con A...

  7. An autocrine ATP release mechanism regulates basal ciliary activity in airway epithelium. (United States)

    Droguett, Karla; Rios, Mariana; Carreño, Daniela V; Navarrete, Camilo; Fuentes, Christian; Villalón, Manuel; Barrera, Nelson P


    Extracellular ATP, in association with [Ca 2+ ] i regulation, is required to maintain basal ciliary beat frequency. Increasing extracellular ATP levels increases ciliary beating in airway epithelial cells, maintaining a sustained response by inducing the release of additional ATP. Extracellular ATP levels in the millimolar range, previously associated with pathophysiological conditions of the airway epithelium, produce a transient arrest of ciliary activity. The regulation of ciliary beat frequency is dependent on ATP release by hemichannels (connexin/pannexin) and P2X receptor activation, the blockage of which may even stop ciliary movement. The force exerted by cilia, measured by atomic force microscopy, is reduced following extracellular ATP hydrolysis. This result complements the current understanding of the ciliary beating regulatory mechanism, with special relevance to inflammatory diseases of the airway epithelium that affect mucociliary clearance. Extracellular nucleotides, including ATP, are locally released by the airway epithelium and stimulate ciliary activity in a [Ca 2+ ] i -dependent manner after mechanical stimulation of ciliated cells. However, it is unclear whether the ATP released is involved in regulating basal ciliary activity and mediating changes in ciliary activity in response to chemical stimulation. In the present study, we evaluated ciliary beat frequency (CBF) and ciliary beating forces in primary cultures from mouse tracheal epithelium, using videomicroscopy and atomic force microscopy (AFM), respectively. Extracellular ATP levels and [Ca 2+ ] i were measured by luminometric and fluorimetric assays, respectively. Uptake of ethidium bromide was measured to evaluate hemichannel functionality. We show that hydrolysis of constitutive extracellular ATP levels with apyrase (50 U ml -1 ) reduced basal CBF by 45% and ciliary force by 67%. The apyrase effect on CBF was potentiated by carbenoxolone, a hemichannel inhibitor, and oxidized ATP, an

  8. A novel adoptive transfer model of chronic lymphocytic leukemia suggests a key role for T lymphocytes in the disease


    Bagnara, Davide; Kaufman, Matthew S.; Calissano, Carlo; Marsilio, Sonia; Patten, Piers E. M.; Simone, Rita; Chum, Philip; Yan, Xiao-Jie; Allen, Steven L.; Kolitz, Jonathan E.; Baskar, Sivasubramanian; Rader, Christoph; Mellstedt, Hakan; Rabbani, Hodjattallah; Lee, Annette


    Chronic lymphocytic leukemia (CLL) is an incurable adult disease of unknown etiology. Understanding the biology of CLL cells, particularly cell maturation and growth in vivo, has been impeded by lack of a reproducible adoptive transfer model. We report a simple, reproducible system in which primary CLL cells proliferate in nonobese diabetes/severe combined immunodeficiency/γcnull mice under the influence of activated CLL-derived T lymphocytes. By cotransferring autologous T lymphocytes, activ...

  9. Mitochondria Targeted Nanoscale Zeolitic Imidazole Framework-90 for ATP Imaging in Live Cells. (United States)

    Deng, Jingjing; Wang, Kai; Wang, Ming; Yu, Ping; Mao, Lanqun


    Zeolitic imidazole frameworks (ZIFs) are an emerging class of functional porous materials with promising biomedical applications such as molecular sensing and intracellular drug delivery. We report herein the first example of using nanoscale ZIFs (i.e., ZIF-90), self-assembled from Zn 2+ and imidazole-2-carboxyaldehyde, to target subcellular mitochondria and image dynamics of mitochondrial ATP in live cells. Encapsulation of fluorescent Rhodamine B (RhB) into ZIF-90 suppresses the emission of RhB, while the competitive coordination between ATP and the metal node of ZIF-90 dissembles ZIFs, resulting in the release of RhB for ATP sensing. With this method, we are able to image mitochondrial ATP in live cells and study the ATP level fluctuation in cellular glycolysis and apoptosis processes. The strategy reported here could be further extended to tune nanoscale ZIFs inside live cells for targeted delivery of therapeutics to subcellular organelles for advanced biomedical applications.

  10. Coupling of kinesin ATP turnover to translocation and microtubule regulation: one engine, many machines. (United States)

    Friel, Claire T; Howard, Jonathon


    The cycle of ATP turnover is integral to the action of motor proteins. Here we discuss how variation in this cycle leads to variation of function observed amongst members of the kinesin superfamily of microtubule associated motor proteins. Variation in the ATP turnover cycle among superfamily members can tune the characteristic kinesin motor to one of the range of microtubule-based functions performed by kinesins. The speed at which ATP is hydrolysed affects the speed of translocation. The ratio of rate constants of ATP turnover in relation to association and dissociation from the microtubule influence the processivity of translocation. Variation in the rate-limiting step of the cycle can reverse the way in which the motor domain interacts with the microtubule producing non-motile kinesins. Because the ATP turnover cycle is not fully understood for the majority of kinesins, much work remains to show how the kinesin engine functions in such a wide variety of molecular machines.

  11. New control method of on-board ATP system of Shinkansen trains

    Energy Technology Data Exchange (ETDEWEB)

    Fukuda, N.; Watanabe, T. [Railway Technical Research Inst. (Japan)


    We studied a new control method of the on-board automatic train protection (ATP) system for Shinkansen trains to shorten the operation time and not to degrade ride comfort at changes in deceleration of the train, while maintaining the safety and reliability of the present ATP signal system. We propose a new on-board pattern brake control system based on the present ATP data without changing the wayside equipment. By simulating the ATP braking of the proposed control method, we succeeded in shortening the operation time by 48 seconds per one station in comparison with the present ATP brake control system. This paper reports the concept of the system and simulation results of the on-board pattern. (orig.)

  12. Kinetic properties of ATP sulfurylase and APS kinase from Thiobacillus denitrificans. (United States)

    Gay, Sean C; Fribourgh, Jennifer L; Donohoue, Paul D; Segel, Irwin H; Fisher, Andrew J


    The Thiobacillus denitrificans genome contains two sequences corresponding to ATP sulfurylase (Tbd_0210 and Tbd_0874). Both genes were cloned and expressed protein characterized. The larger protein (Tbd_0210; 544 residues) possesses an N-terminal ATP sulfurylase domain and a C-terminal APS kinase domain and was therefore annotated as a bifunctional enzyme. But, the protein was not bifunctional because it lacked ATP sulfurylase activity. However, the enzyme did possess APS kinase activity and displayed substrate inhibition by APS. Truncated protein missing the N-terminal domain had APS kinase activity suggesting the function of the inactive sulfurylase domain is to promote the oligomerization of the APS kinase domains. The smaller gene product (Tbd_0874; 402 residues) possessed strong ATP sulfurylase activity with kinetic properties that appear to be kinetically optimized for the direction of APS utilization and ATP+sulfate production, which is consistent with an enzyme that functions physiologically to produce inorganic sulfate.

  13. Altered localisation of the copper efflux transporters ATP7A and ATP7B associated with cisplatin resistance in human ovarian carcinoma cells

    International Nuclear Information System (INIS)

    Kalayda, Ganna V; Wagner, Christina H; Buß, Irina; Reedijk, Jan; Jaehde, Ulrich


    Copper homeostasis proteins ATP7A and ATP7B are assumed to be involved in the intracellular transport of cisplatin. The aim of the present study was to assess the relevance of sub cellular localisation of these transporters for acquired cisplatin resistance in vitro. For this purpose, localisation of ATP7A and ATP7B in A2780 human ovarian carcinoma cells and their cisplatin-resistant variant, A2780cis, was investigated. Sub cellular localisation of ATP7A and ATP7B in sensitive and resistant cells was investigated using confocal fluorescence microscopy after immunohistochemical staining. Co-localisation experiments with a cisplatin analogue modified with a carboxyfluorescein-diacetate residue were performed. Cytotoxicity of the fluorescent cisplatin analogue in A2780 and A2780cis cells was determined using an MTT-based assay. The significance of differences was analysed using Student's t test or Mann-Whitney test as appropriate, p values of < 0.05 were considered significant. In the sensitive cells, both transporters are mainly localised in the trans-Golgi network, whereas they are sequestrated in more peripherally located vesicles in the resistant cells. Altered localisation of ATP7A and ATP7B in A2780cis cells is likely to be a consequence of major abnormalities in intracellular protein trafficking related to a reduced lysosomal compartment in this cell line. Changes in sub cellular localisation of ATP7A and ATP7B may facilitate sequestration of cisplatin in the vesicular structures of A2780cis cells, which may prevent drug binding to genomic DNA and thereby contribute to cisplatin resistance. Our results indicate that alterations in sub cellular localisation of transport proteins may contribute to cisplatin resistance in vitro. Investigation of intracellular protein localisation in primary tumour cell cultures and tumour tissues may help to develop markers of clinically relevant cisplatin resistance. Detection of resistant tumours in patients may in turn

  14. Altered localisation of the copper efflux transporters ATP7A and ATP7B associated with cisplatin resistance in human ovarian carcinoma cells

    Directory of Open Access Journals (Sweden)

    Reedijk Jan


    Full Text Available Abstract Background Copper homeostasis proteins ATP7A and ATP7B are assumed to be involved in the intracellular transport of cisplatin. The aim of the present study was to assess the relevance of sub cellular localisation of these transporters for acquired cisplatin resistance in vitro. For this purpose, localisation of ATP7A and ATP7B in A2780 human ovarian carcinoma cells and their cisplatin-resistant variant, A2780cis, was investigated. Methods Sub cellular localisation of ATP7A and ATP7B in sensitive and resistant cells was investigated using confocal fluorescence microscopy after immunohistochemical staining. Co-localisation experiments with a cisplatin analogue modified with a carboxyfluorescein-diacetate residue were performed. Cytotoxicity of the fluorescent cisplatin analogue in A2780 and A2780cis cells was determined using an MTT-based assay. The significance of differences was analysed using Student's t test or Mann-Whitney test as appropriate, p values of Results In the sensitive cells, both transporters are mainly localised in the trans-Golgi network, whereas they are sequestrated in more peripherally located vesicles in the resistant cells. Altered localisation of ATP7A and ATP7B in A2780cis cells is likely to be a consequence of major abnormalities in intracellular protein trafficking related to a reduced lysosomal compartment in this cell line. Changes in sub cellular localisation of ATP7A and ATP7B may facilitate sequestration of cisplatin in the vesicular structures of A2780cis cells, which may prevent drug binding to genomic DNA and thereby contribute to cisplatin resistance. Conclusion Our results indicate that alterations in sub cellular localisation of transport proteins may contribute to cisplatin resistance in vitro. Investigation of intracellular protein localisation in primary tumour cell cultures and tumour tissues may help to develop markers of clinically relevant cisplatin resistance. Detection of resistant tumours

  15. The molecular motor F-ATP synthase is targeted by the tumoricidal protein HAMLET. (United States)

    Ho, James; Sielaff, Hendrik; Nadeem, Aftab; Svanborg, Catharina; Grüber, Gerhard


    HAMLET (human alpha-lactalbumin made lethal to tumor cells) interacts with multiple tumor cell compartments, affecting cell morphology, metabolism, proteasome function, chromatin structure and viability. This study investigated if these diverse effects of HAMLET might be caused, in part, by a direct effect on the ATP synthase and a resulting reduction in cellular ATP levels. A dose-dependent reduction in cellular ATP levels was detected in A549 lung carcinoma cells, and by confocal microscopy, co-localization of HAMLET with the nucleotide-binding subunits α (non-catalytic) and β (catalytic) of the energy converting F1F0 ATP synthase was detected. As shown by fluorescence correlation spectroscopy, HAMLET binds to the F1 domain of the F1F0 ATP synthase with a dissociation constant (KD) of 20.5μM. Increasing concentrations of the tumoricidal protein HAMLET added to the enzymatically active α3β3γ complex of the F-ATP synthase lowered its ATPase activity, demonstrating that HAMLET binding to the F-ATP synthase effects the catalysis of this molecular motor. Single-molecule analysis was applied to study HAMLET-α3β3γ complex interaction. Whereas the α3β3γ complex of the F-ATP synthase rotated in a counterclockwise direction with a mean rotational rate of 3.8±0.7s(-1), no rotation could be observed in the presence of bound HAMLET. Our findings suggest that direct effects of HAMLET on the F-ATP synthase may inhibit ATP-dependent cellular processes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Lymphocyte electrotaxis in vitro and in vivo. (United States)

    Lin, Francis; Baldessari, Fabio; Gyenge, Christina Crenguta; Sato, Tohru; Chambers, Robert D; Santiago, Juan G; Butcher, Eugene C


    Electric fields are generated in vivo in a variety of physiologic and pathologic settings, including penetrating injury to epithelial barriers. An applied electric field with strength within the physiologic range can induce directional cell migration (i.e., electrotaxis) of epithelial cells, endothelial cells, fibroblasts, and neutrophils suggesting a potential role in cell positioning during wound healing. In the present study, we investigated the ability of lymphocytes to respond to applied direct current (DC) electric fields. Using a modified Transwell assay and a simple microfluidic device, we show that human PBLs migrate toward the cathode in physiologically relevant DC electric fields. Additionally, electrical stimulation activates intracellular kinase signaling pathways shared with chemotactic stimuli. Finally, video microscopic tracing of GFP-tagged immunocytes in the skin of mouse ears reveals that motile cutaneous T cells actively migrate toward the cathode of an applied DC electric field. Lymphocyte positioning within tissues can thus be manipulated by externally applied electric fields, and may be influenced by endogenous electrical potential gradients as well.

  17. Crosstalk between T lymphocytes and dendritic cells. (United States)

    Hivroz, Claire; Chemin, Karine; Tourret, Marie; Bohineust, Armelle


    Dendritic cells (DCs) are professional antigen-presenting cells (APCs) with the unique property of inducing priming and differentiation of naïve CD4+ and CD8+ T cells into helper and cytotoxic effectors. Their efficiency is due to their unique ability to process antigen, express costimulatory molecules, secrete cytokines, and migrate to tissues or lymphoid organs to prime T cells. DCs also play an important role in T-cell peripheral tolerance. There is ample evidence that the DC ability to present antigens is regulated by CD4+ helper T cells. Indeed, interactions between surface receptors and ligands expressed respectively by T cells and DCs, as well as T-cell-derived cytokines modify DC functions. This T-cell-induced modification of DCs has been called "education" or "licensing." This intimate crosstalk between DCs and T lymphocytes is key in establishing appropriate adaptive immune responses. It requires cognate interactions between T lymphocytes and DCs, which are organized in time and space by structures called immunological synapses. Here we discuss the particular aspects of immunological synapses formed between T cells and DCs and the role these organized interactions have in T-cell-DC crosstalk.

  18. Large granular lymphocytic leukaemia pathogenesis and management. (United States)

    Dearden, Claire


    The WHO classification recognises three distinct disorders of large granular lymphocytes: T-cell large granular lymphocytic leukaemia (T-LGL), chronic lymphoproliferative disorders of NK-cells (CLPD-NK) and agressive NK-cell leukaemia. Despite the different cell of origin, there is considerable overlap between T-LGL and CLPD-NK in terms of clinical presentation and therapy. Many patients are asymptomatic and do not require treatment. Therapy, with immunosuppressant agents such as low dose methotrexate or ciclosporin, is usually indicated to correct cytopenias. In contrast, aggressive NK-cell leukaemia and the rare CD56(+) aggressive T-LGL leukaemia follow a fulminant clinical course, affect younger individuals and require more intensive combination chemotherapy followed by allogeneic stem cell transplant in eligible patients. The relative rarity of these disorders means that there have been few clinical trials to inform management. However, there is now considerable interest in the pathogenesis of the chronic LGL leukaemias and this has stimulated early trials to evaluate novel agents which target the dysregulated apoptotic pathways characteristic of this disease. © 2010 Blackwell Publishing Ltd.

  19. ATP-Citrate Lyase Controls a Glucose-to-Acetate Metabolic Switch

    Directory of Open Access Journals (Sweden)

    Steven Zhao


    Full Text Available Mechanisms of metabolic flexibility enable cells to survive under stressful conditions and can thwart therapeutic responses. Acetyl-coenzyme A (CoA plays central roles in energy production, lipid metabolism, and epigenomic modifications. Here, we show that, upon genetic deletion of Acly, the gene coding for ATP-citrate lyase (ACLY, cells remain viable and proliferate, although at an impaired rate. In the absence of ACLY, cells upregulate ACSS2 and utilize exogenous acetate to provide acetyl-CoA for de novo lipogenesis (DNL and histone acetylation. A physiological level of acetate is sufficient for cell viability and abundant acetyl-CoA production, although histone acetylation levels remain low in ACLY-deficient cells unless supplemented with high levels of acetate. ACLY-deficient adipocytes accumulate lipid in vivo, exhibit increased acetyl-CoA and malonyl-CoA production from acetate, and display some differences in fatty acid content and synthesis. Together, these data indicate that engagement of acetate metabolism is a crucial, although partial, mechanism of compensation for ACLY deficiency.

  20. ATP-Citrate Lyase Controls a Glucose-to-Acetate Metabolic Switch. (United States)

    Zhao, Steven; Torres, AnnMarie; Henry, Ryan A; Trefely, Sophie; Wallace, Martina; Lee, Joyce V; Carrer, Alessandro; Sengupta, Arjun; Campbell, Sydney L; Kuo, Yin-Ming; Frey, Alexander J; Meurs, Noah; Viola, John M; Blair, Ian A; Weljie, Aalim M; Metallo, Christian M; Snyder, Nathaniel W; Andrews, Andrew J; Wellen, Kathryn E


    Mechanisms of metabolic flexibility enable cells to survive under stressful conditions and can thwart therapeutic responses. Acetyl-coenzyme A (CoA) plays central roles in energy production, lipid metabolism, and epigenomic modifications. Here, we show that, upon genetic deletion of Acly, the gene coding for ATP-citrate lyase (ACLY), cells remain viable and proliferate, although at an impaired rate. In the absence of ACLY, cells upregulate ACSS2 and utilize exogenous acetate to provide acetyl-CoA for de novo lipogenesis (DNL) and histone acetylation. A physiological level of acetate is sufficient for cell viability and abundant acetyl-CoA production, although histone acetylation levels remain low in ACLY-deficient cells unless supplemented with high levels of acetate. ACLY-deficient adipocytes accumulate lipid in vivo, exhibit increased acetyl-CoA and malonyl-CoA production from acetate, and display some differences in fatty acid content and synthesis. Together, these data indicate that engagement of acetate metabolism is a crucial, although partial, mechanism of compensation for ACLY deficiency. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  1. The immunodeficiency of bone marrow-transplanted patients. II. CD8-related suppression by patient lymphocytes of the response of donor lymphocytes to mitogens, antigens, and allogeneic cells

    DEFF Research Database (Denmark)

    Ødum, Niels; Hofmann, B; Jacobsen, N


    Lymphocytes from 21 patients sampled 1-6 months after bone marrow transplantation (BMT) were tested for functional suppressor activity against marrow-donor lymphocytes in the lymphocyte transformation test. Suppression of donor responses to allogeneic (i.e. mixed lymphocyte reaction, MLR...

  2. Glycolysis-related gene induction and ATP reduction during fractionated irradiation. Markers for radiation responsiveness of human tumor xenografts

    Energy Technology Data Exchange (ETDEWEB)

    Goetze, K.; Meyer, S.S.; Mueller-Klieser, W. [University Medical Center Mainz Univ. (Germany). Inst. of Physiology and Pathophysiology; Yaromina, A. [Technical Univ. Dresden (Germany). OncoRay - National Center for Radiation Research in Oncology; Zips, D. [University Hospital Tuebingen (Germany). Dept. of Radiation Oncology; Baumann, M. [Technical Univ. Dresden (Germany). OncoRay - National Center for Radiation Research in Oncology; University Hospital Dresden Technical Univ. Dresden (Germany). Dept. of Radiation Oncology


    Background and purpose: Lactate was previously shown to be a prognostic but not a predictive pre-therapeutic marker for radiation response of tumor xenografts. We hypothesize that metabolic changes during fractionated irradiation may restrict the predictiveness of lactate regarding tumor radiosensitivity. Materials and methods: Tumor xenografts were generated in nude mice by implanting 4 head and neck squamous cell carcinoma lines with different sensitivities to fractionated irradiation. Tumors were irradiated with up to 15 fractions of 2 Gy over a period of 3 weeks, and ATP and lactate levels were measured in vital tumor areas with induced metabolic bioluminescence imaging. Corresponding changes in mRNA expression of glycolysis-related genes were determined by quantitative RT-PCR. Results: Lactate content decreased significantly in 3 out of 4 cell lines in the course of irradiation showing no correlation with cell line-specific radiosensitivity. Radiation-induced changes in ATP levels and glycolysis-related mRNA expression, however, only occurred in radiosensitive or intermediately radioresistant xenografts, whereas these parameters remained unchanged in radioresistant tumors. Conclusion: Sensitivity-related differences in the transcriptional response of tumors to radiotherapy may be exploited in the clinic for better individualization of tumor treatment. (orig.)

  3. Telomerase levels control the lifespan of human T lymphocytes

    NARCIS (Netherlands)

    Roth, Alexander; Yssel, Hans; Pene, Jerome; Chavez, Elizabeth A.; Schertzer, Mike; Lansdorp, Peter M.; Spits, Hergen; Luiten, Rosalie M.


    The loss of telomeric DNA with each cell division contributes to the limited replicative lifespan of human T lymphocytes. Although telomerase is transiently expressed in T lymphocytes upon activation, it is insufficient to confer immortality. We have previously shown that immortalization of human

  4. Apoptosis of lymphocytes in SLE: the level, correlation with ...

    African Journals Online (AJOL)

    Lymphocytes were isolated from venous blood by method of gradient centrifugation of all the blood through a Ficoll-pak solution. The quantity apoptotic cells was determined in leukocytes by flow cytometry Epics XL-2 (“Beckman Coulter”, USA). Analysis of lymphocyte subpopulations was carried by using two fluorescent ...

  5. 9 CFR 113.42 - Detection of lymphocytic choriomeningitis contamination. (United States)


    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Detection of lymphocytic choriomeningitis contamination. 113.42 Section 113.42 Animals and Animal Products ANIMAL AND PLANT HEALTH... contamination. The test for detection of lymphocytic choriomeningitis (LCM) virus provided in this section shall...

  6. Role of interferon in lymphocyte recruitment into the skin

    International Nuclear Information System (INIS)

    Issekutz, T.B.; Stoltz, J.M.; Webster, D.M.


    Large numbers of lymphocytes are recruited from the blood into sites of cutaneous DTH reactions. Our goal was to investigate the factors controlling this recruitment. 111 In-labeled peritoneal exudate lymphocytes were injected iv and the accumulation of these cells in skin sites injected with a variety of stimuli, was used to measure lymphocyte recruitment in rats. Large numbers of lymphocytes migrated into vaccinia- and KLH-injected sites in sensitized animals, but only into the viral and not the KLH lesions in non-immune animals. Lymphocytes also migrated efficiently into sites injected with the alpha-interferon (IFN) inducers, uv-inactivated vaccinia virus and poly I:C, as well as into sites injected with IFN. In each case there was a dose-response relationship. Analysis of the kinetics of lymphocyte recruitment demonstrated that the peak rate of migration occurred most rapidly after the injection of IFN, later after poly I:C, and was slowest to be reached after vaccinia virus. Rabbit anti-IFN blocked the recruitment of lymphocytes by uv-inactivated vaccinia and by IFN. Histologically, all of these sites demonstrated a dense mononuclear cell infiltrate in the dermis. It is suggested that IFN may be an important mediator in the recruitment of lymphocytes into inflammatory reactions

  7. 21 CFR 864.8500 - Lymphocyte separation medium. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Lymphocyte separation medium. 864.8500 Section 864.8500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8500 Lymphocyte separation...

  8. Immunophenotypic enumeration of CD4 T-lymphocyte values in ...

    African Journals Online (AJOL)


    lymphocytes play a central role in regulation of immune response.[2] These ..... influence of sex hormones on lymphocyte subpopulations. ... Friedland GH. Early treatment for HIV-The Time. Has Come. N Engl J Med 1990;322:1000-1002. 7. Gebo KA, Gallant JE, Keruly JC, Moore RD. Absolute CD4 vs. CD4 percentage for ...

  9. Cytogenetical analysis in blood lymphocytes of cigarette smokers in ...

    African Journals Online (AJOL)

    Comet assay showed increased percentage of abnormalities in smokers (light, medium and heavy) than non-smokers. Conclusion: The frequencies of MN in buccal epithelial and blood lymphocytes are high in smokers; particularly heavy smoker group showed significantly increased results. Among them, the lymphocytic ...

  10. Lymphocytes as a neural probe : potential for studying psychiatric disorders

    NARCIS (Netherlands)

    Gladkevich, A; Kauffman, HF; Korf, J

    There is an increasing body evidence pointing to a close integration between the central nervous system (CNS) and immunological functions with lymphocytes playing therein a central role. The authors provide arguments to consider blood lymphocytes as a convenient probe of-an albeit-limited number of

  11. Intestinal T lymphocytes of different rat strains in immunotoxicity

    NARCIS (Netherlands)

    Bruder, M.C.; Spanhaak, S.; Bruijntjes, J.P.; Michielsen, C.P.P.C.; Vos, J.G.; Kuper, C.F.


    In order to study the intestinal mucosal immune cells, with emphasis on single T lymphocytcs, an inventory was made of single and organized lymphocytes in the epithelium and lamina propria of the small intestines of untreated Wistar, Fischer 344, and Lewis rats. The single and organized lymphocytes

  12. Activation of human T lymphocytes by Leishmania lipophosphoglycan

    DEFF Research Database (Denmark)

    Kemp, M; Theander, T G; Handman, E


    This study describes Leishmania antigen-induced activation of lymphocytes isolated from Kenyan donors, previously treated for visceral leishmaniasis, and from Danish and Kenyan controls. Peripheral blood mononuclear cells (PBMC) from cured Kala-Azar patients proliferated and produced Interferon......, the results suggest that human T lymphocytes can respond to glycolipid antigens....

  13. Carotenoid levels in human lymphocytes, measured by Raman microspectroscopy

    NARCIS (Netherlands)

    Ramanauskaite, R B; SegersNolten, IGMJ; DeGrauw, K J; Sijtsema, N M; VanderMaas, L; Greve, J; Otto, C; Figdor, C G


    Carotenoid levels in lymphocytes obtained from peripheral blood of healthy people have been investigated by Raman microspectroscopy. We observed that carotenoids are concentrated in so-called ''Gall bodies''. The level of carotenoids in living human lymphocytes was found to be age-dependent and to

  14. T gamma/delta lymphocytes in renal transplant recipients

    NARCIS (Netherlands)

    Raasveld, M. H.; Bloemena, E.; Surachno, S.; ten Berge, R. J.


    T gamma/delta lymphocytes are able to perform allospecific cytotoxicity and natural killer cytotoxicity in vitro. However, very little is known about their function in vivo. To investigate the possible involvement of T gamma/delta lymphocytes in the immune response to renal allografts, fine-needle

  15. ATP binding cassette G1-dependent cholesterol efflux during inflammation. (United States)

    de Beer, Maria C; Ji, Ailing; Jahangiri, Anisa; Vaughan, Ashley M; de Beer, Frederick C; van der Westhuyzen, Deneys R; Webb, Nancy R


    ATP binding cassette transporter G1 (ABCG1) mediates the transport of cellular cholesterol to HDL, and it plays a key role in maintaining macrophage cholesterol homeostasis. During inflammation, HDL undergoes substantial remodeling, acquiring lipid changes and serum amyloid A (SAA) as a major apolipoprotein. In the current study, we investigated whether remodeling of HDL that occurs during acute inflammation impacts ABCG1-dependent efflux. Our data indicate that lipid free SAA acts similarly to apolipoprotein A-I (apoA-I) in mediating sequential efflux from ABCA1 and ABCG1. Compared with normal mouse HDL, acute phase (AP) mouse HDL containing SAA exhibited a modest but significant 17% increase in ABCG1-dependent efflux. Interestingly, AP HDL isolated from mice lacking SAA (SAAKO mice) was even more effective in promoting ABCG1 efflux. Hydrolysis with Group IIA secretory phospholipase A(2) (sPLA(2)-IIA) significantly reduced the ability of AP HDL from SAAKO mice to serve as a substrate for ABCG1-mediated cholesterol transfer, indicating that phospholipid (PL) enrichment, and not the presence of SAA, is responsible for alterations in efflux. AP human HDL, which is not PL-enriched, was somewhat less effective in mediating ABCG1-dependent efflux compared with normal human HDL. Our data indicate that inflammatory remodeling of HDL impacts ABCG1-dependent efflux independent of SAA.

  16. Aluminum chloride- and norepinephrine-induced immunotoxicity on splenic lymphocytes by activating β2-AR/cAMP/PKA/NF-κB signal pathway in rats. (United States)

    Xiu, Chunyu; Ren, Limin; Li, Miao; Liu, Shiming; Zhu, Yanzhu; Liu, Jianyu; Li, Yanfei


    We found in our previous research that aluminum (Al) exposure induced immunotoxicity on spleen and increased norepinephrine (NE) content in serum from rats. However, it is unclear how NE is involved in the AlCl3 immunotoxicity on rats. Therefore, this experiment was designed to explore the mechanism of AlCl3 and NE-induced immunotoxicity on the splenic lymphocytes. Eighty male Wistar rats were orally exposed to AlCl3 (0, 64, 128, and 256 mg/kg BW) through drinking water for 120 days. Al contents in brain and spleen; NE contents in serum and in the hypothalamus; β2-AR density; cAMP content; β2-AR, PKA, and NF-κB mRNA expression levels; and protein expressions of PKA and nuclear NF-κB in splenic lymphocytes of AlCl3-treated rats were examined. The results showed that AlCl3 increased NE content in serum, the β2-AR density, the β2-AR and PKA (C-subunits) mRNA expression levels, cAMP content and the PKA (C-subunits) protein expression levels in lymphocytes, whereas, decreased NE content in the hypothalamus, the NF-κB (p65) mRNA expression level and nuclear NF-κB (p65) protein expression level in lymphocytes. These results indicated that the accumulated AlCl3 in spleen and the increased NE in serum induced the immunotoxicity on splenic lymphocytes by activating β2-AR/cAMP/PKA/NF-κB signal pathway in rats.

  17. Structural and biochemical studies on ATP binding and hydrolysis by the Escherichia coli RNA chaperone Hfq.

    Directory of Open Access Journals (Sweden)

    Hermann Hämmerle

    Full Text Available In Escherichia coli the RNA chaperone Hfq is involved in riboregulation by assisting base-pairing between small regulatory RNAs (sRNAs and mRNA targets. Several structural and biochemical studies revealed RNA binding sites on either surface of the donut shaped Hfq-hexamer. Whereas sRNAs are believed to contact preferentially the YKH motifs present on the proximal site, poly(A(15 and ADP were shown to bind to tripartite binding motifs (ARE circularly positioned on the distal site. Hfq has been reported to bind and to hydrolyze ATP. Here, we present the crystal structure of a C-terminally truncated variant of E. coli Hfq (Hfq(65 in complex with ATP, showing that it binds to the distal R-sites. In addition, we revisited the reported ATPase activity of full length Hfq purified to homogeneity. At variance with previous reports, no ATPase activity was observed for Hfq. In addition, FRET assays neither indicated an impact of ATP on annealing of two model oligoribonucleotides nor did the presence of ATP induce strand displacement. Moreover, ATP did not lead to destabilization of binary and ternary Hfq-RNA complexes, unless a vast stoichiometric excess of ATP was used. Taken together, these studies strongly suggest that ATP is dispensable for and does not interfere with Hfq-mediated RNA transactions.

  18. Dynamics of shear-induced ATP release from red blood cells. (United States)

    Wan, Jiandi; Ristenpart, William D; Stone, Howard A


    Adenosine triphosphate (ATP) is a regulatory molecule for many cell functions, both for intracellular and, perhaps less well known, extracellular functions. An important example of the latter involves red blood cells (RBCs), which help regulate blood pressure by releasing ATP as a vasodilatory signaling molecule in response to the increased shear stress inside arterial constrictions. Although shear-induced ATP release has been observed widely and is believed to be triggered by deformation of the cell membrane, the underlying mechanosensing mechanism inside RBCs is still controversial. Here, we use an in vitro microfluidic approach to investigate the dynamics of shear-induced ATP release from human RBCs with millisecond resolution. We demonstrate that there is a sizable delay time between the onset of increased shear stress and the release of ATP. This response time decreases with shear stress, but surprisingly does not depend significantly on membrane rigidity. Furthermore, we show that even though the RBCs deform significantly in short constrictions (duration of increased stress <3 ms), no measurable ATP is released. This critical timescale is commensurate with a characteristic membrane relaxation time determined from observations of the cell deformation by using high-speed video. Taken together our results suggest a model wherein the retraction of the spectrin-actin cytoskeleton network triggers the mechanosensitive ATP release and a shear-dependent membrane viscosity controls the rate of release.

  19. Motility, ATP levels and metabolic enzyme activity of sperm from bluegill (Lepomis macrochirus). (United States)

    Burness, Gary; Moyes, Christopher D; Montgomerie, Robert


    Male bluegill displays one of two life history tactics. Some males (termed "parentals") delay reproduction until ca. 7 years of age, at which time they build nests and actively courts females. Others mature precociously (sneakers) and obtain fertilizations by cuckolding parental males. In the current study, we studied the relations among sperm motility, ATP levels, and metabolic enzyme activity in parental and sneaker bluegill. In both reproductive tactics, sperm swimming speed and ATP levels declined in parallel over the first 60 s of motility. Although sneaker sperm initially had higher ATP levels than parental sperm, by approximately 30 s postactivation, no differences existed between tactics. No differences were noted between tactics in swimming speed, percent motility, or the activities of key metabolic enzymes, although sperm from parentals had a higher ratio of creatine phosphokinase (CPK) to citrate synthase (CS). In both tactics, with increasing CPK and CS activity, sperm ATP levels increased at 20 s postactivation, suggesting that capacities for phosphocreatine hydrolysis and aerobic metabolism may influence interindividual variation in rates of ATP depletion. Nonetheless, there was no relation between sperm ATP levels and either swimming speed or percent of sperm that were motile. This suggests that interindividual variation in ATP levels may not be the primary determinant of variation in sperm swimming performance in bluegill.

  20. Stoichiometry of ATP hydrolysis and chlorophyllide formation of dark-operative protochlorophyllide oxidoreductase from Rhodobacter capsulatus

    Energy Technology Data Exchange (ETDEWEB)

    Nomata, Jiro [Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601 (Japan); Terauchi, Kazuki [Department of Life Sciences, Ritsumeikan University, Kusatsu, Shiga, 525-8577 (Japan); Fujita, Yuichi, E-mail: [Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601 (Japan)


    Dark-operative protochlorophyllide (Pchlide) oxidoreductase (DPOR) is a nitrogenase-like enzyme catalyzing a reduction of the C17 = C18 double bond of Pchlide to form chlorophyllide a (Chlide) in bacteriochlorophyll biosynthesis. DPOR consists of an ATP-dependent reductase component, L-protein (a BchL dimer), and a catalytic component, NB-protein (a BchN–BchB heterotetramer). The L-protein transfers electrons to the NB-protein to reduce Pchlide, which is coupled with ATP hydrolysis. Here we determined the stoichiometry of ATP hydrolysis and the Chlide formation of DPOR. The minimal ratio of ATP to Chlide (ATP/2e{sup –}) was 4, which coincides with that of nitrogenase. The ratio increases with increasing molar ratio of L-protein to NB-protein. This profile differs from that of nitrogenase. These results suggest that DPOR has a specific intrinsic property, while retaining the common features shared with nitrogenase. - Highlights: • The stoichiometry of nitrogenase-like protochlorophyllide reductase was determined. • The minimal ATP/2e{sup –} ratio was 4, which coincides with that of nitrogenase. • The ATP/2e{sup –} ratio increases with increasing L-protein/NB-protein molar ratio. • DPOR has an intrinsic property, but retains features shared with nitrogenase.

  1. Ca2+ Entry is Required for Mechanical Stimulation-induced ATP Release from Astrocyte (United States)

    Lee, Jaekwang; Chun, Ye-Eun; Han, Kyung-Seok; Lee, Jungmoo; Woo, Dong Ho


    Astrocytes and neurons are inseparable partners in the brain. Neurotransmitters released from neurons activate corresponding G protein-coupled receptors (GPCR) expressed in astrocytes, resulting in release of gliotransmitters such as glutamate, D-serine, and ATP. These gliotransmitters in turn influence neuronal excitability and synaptic activities. Among these gliotransmitters, ATP regulates the level of network excitability and is critically involved in sleep homeostasis and astrocytic Ca2+ oscillations. ATP is known to be released from astrocytes by Ca2+-dependent manner. However, the precise source of Ca2+, whether it is Ca2+ entry from outside of cell or from the intracellular store, is still not clear yet. Here, we performed sniffer patch to detect ATP release from astrocyte by using various stimulation. We found that ATP was not released from astrocyte when Ca2+ was released from intracellular stores by activation of Gαq-coupled GPCR including PAR1, P2YR, and B2R. More importantly, mechanical stimulation (MS)-induced ATP release from astrocyte was eliminated when external Ca2+ was omitted. Our results suggest that Ca2+ entry, but not release from intracellular Ca2+ store, is critical for MS-induced ATP release from astrocyte. PMID:25792866

  2. The Activity of Menkes Disease Protein ATP7A Is Essential for Redox Balance in Mitochondria

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharjee, Ashima; Yang, Haojun; Duffy, Megan; Robinson, Emily; Conrad-Antoville, Arianrhod; Lu, Ya-Wen; Capps, Tony; Braiterman, Lelita; Wolfgang, Michael; Murphy, Michael P.; Yi, Ling; Kaler, Stephen G.; Lutsenko, Svetlana; Ralle, Martina


    Copper-transporting ATPase ATP7A is essential for mammalian copper homeostasis. Loss of ATP7A activity is associated with fatal Menkes disease and various other pathologies. In cells, ATP7A inactivation disrupts copper transport from the cytosol into the secretory pathway. Using fibroblasts from Menkes disease patients and mouse 3T3-L1 cells with a CRISPR/Cas9-inactivated ATP7A, we demonstrate that ATP7A dysfunction is also damaging to mitochondrial redox balance. In these cells, copper accumulates in nuclei, cytosol, and mitochondria, causing distinct changes in their redox environment. Quantitative imaging of live cells using GRX1-roGFP2 and HyPer sensors reveals highest glutathione oxidation and elevation of H2O2 in mitochondria, whereas the redox environment of nuclei and the cytosol is much less affected. Decreasing the H2O2 levels in mitochondria with MitoQ does not prevent glutathione oxidation; i.e. elevated copper and not H2O2 is a primary cause of glutathione oxidation. Redox misbalance does not significantly affect mitochondrion morphology or the activity of respiratory complex IV but markedly increases cell sensitivity to even mild glutathione depletion, resulting in loss of cell viability. Thus, ATP7A activity protects mitochondria from excessive copper entry, which is deleterious to redox buffers. Mitochondrial redox misbalance could significantly contribute to pathologies associated with ATP7A inactivation in tissues with paradoxical accumulation of copper (i.e. renal epithelia).

  3. Mice Lacking Pannexin 1 Release ATP and Respond Normally to All Taste Qualities. (United States)

    Vandenbeuch, Aurelie; Anderson, Catherine B; Kinnamon, Sue C


    Adenosine triphosphate (ATP) is required for the transmission of all taste qualities from taste cells to afferent nerve fibers. ATP is released from Type II taste cells by a nonvesicular mechanism and activates purinergic receptors containing P2X2 and P2X3 on nerve fibers. Several ATP release channels are expressed in taste cells including CALHM1, Pannexin 1, Connexin 30, and Connexin 43, but whether all are involved in ATP release is not clear. We have used a global Pannexin 1 knock out (Panx1 KO) mouse in a series of in vitro and in vivo experiments. Our results confirm that Panx1 channels are absent in taste buds of the knockout mice and that other known ATP release channels are not upregulated. Using a luciferin/luciferase assay, we show that circumvallate taste buds from Panx1 KO mice normally release ATP upon taste stimulation compared with wild type (WT) mice. Gustatory nerve recordings in response to various tastants applied to the tongue and brief-access behavioral testing with SC45647 also show no difference between Panx1 KO and WT. These results confirm that Panx1 is not required for the taste evoked release of ATP or for neural and behavioral responses to taste stimuli. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail:

  4. Lymphocytes Mitochondrial Physiology as Biomarker of Energy Metabolism during Fasted and Fed Conditions

    Directory of Open Access Journals (Sweden)

    Erika Cortez


    Full Text Available Mitochondria are central coordinators of energy metabolism, and changes of their physiology have long been associated with metabolic disorders. Thus, observations of energy dynamics in different cell types are of utmost importance. Therefore, tools with quick and easy handling are needed for consistent evaluations of such interventions. In this paper, our main hypothesis is that during different nutritional situations lymphocytes mitochondrial physiology could be associated with the metabolism of other cell types, such as cardiomyocytes, and consequently be used as metabolic biomarker. Blood lymphocytes and heart muscle fibers were obtained from both fed and 24 h-fasted mice, and mitochondrial analysis was assessed by high-resolution respirometry and western blotting. Carbohydrate-linked oxidation and fatty acid oxidation were significantly higher after fasting. Carnitine palmitoil transferase 1 and uncouple protein 2 contents were increased in the fasted group, while the glucose transporters 1 and 4 and the ratio phosphorylated AMP-activated protein kinase/AMPK did not change between groups. In summary, under a nutritional status modification, mitochondria demonstrated earlier adaptive capacity than other metabolic sensors such as glucose transporters and AMPK, suggesting the accuracy of mitochondria physiology of lymphocytes as biomarker for metabolic changes.

  5. Chromium picolinate induced apoptosis of lymphocytes and the signaling mechanisms thereof

    International Nuclear Information System (INIS)

    Jana, Mahadevan; Rajaram, Anantanarayanan; Rajaram, Rama


    Cr(III)(picolinate) 3 [Cr(III)(pic) 3 ] is currently used as a nutritional supplement and for treating Type-2 diabetes. The effect of Cr(III)(pic) 3 uptake in peripheral blood lymphocytes is investigated in this study. From the cytotoxicity data, DNA fragmentation pattern, Annexin V staining, TUNEL positivity and the ultrastructural characteristics such as chromatin condensation and formation of apoptotic bodies, it is clear that Cr(III)(pic) 3 induces a concentration dependent apoptosis. It is shown that reactive oxygen species (ROS) produced by treatment with Cr(III)(pic) 3 leads to apoptosis, since we find that pretreatment with N-acetyl cysteine inhibits the process. Using Western blotting technique and fluorescence measurements, the downstream signaling molecules have also been identified. Cr(III)(pic) 3 treatment leads to collapse of the mitochondrial membrane potential, Bax expression, increase in cytosolic cytochrome c content and active caspase-3 and DNA fragmentation and all these manifestations are reduced by pretreating the lymphocytes with N-acetyl cysteine. Thus, it is shown that Cr(III)(pic) 3 is cytotoxic to lymphocytes with ROS and mitochondrial events playing a role in bringing about apoptosis.

  6. Mesenchymal stromal cells derived from cervical cancer produce high amounts of adenosine to suppress cytotoxic T lymphocyte functions

    Directory of Open Access Journals (Sweden)

    María de Lourdes Mora-García


    Full Text Available Abstract Background In recent years, immunomodulatory mechanisms of mesenchymal stem/stromal cells (MSCs from bone marrow and other “classic” sources have been described. However, the phenotypic and functional properties of tumor MSCs are poorly understood. The aim of this study was to analyze the immunosuppressive capacity of cervical cancer-derived MSCs (CeCa-MSCs on effector T lymphocytes through the purinergic pathway. Methods We determined the expression and functional activity of the membrane-associated ectonucleotidases CD39 and CD73 on CeCa-MSCs and normal cervical tissue-derived MSCs (NCx-MSCs. We also analyzed their immunosuppressive capacity to decrease proliferation, activation and effector cytotoxic T (CD8+ lymphocyte function through the generation of adenosine (Ado. Results We detected that CeCa-MSCs express higher levels of CD39 and CD73 ectonucleotidases in cell membranes compared to NCx-MSCs, and that this feature was associated with the ability to strongly suppress the proliferation, activation and effector functions of cytotoxic T-cells through the generation of large amounts of Ado from the hydrolysis of ATP, ADP and AMP nucleotides. Conclusions This study suggests that CeCa-MSCs play an important role in the suppression of the anti-tumor immune response in CeCa through the purinergic pathway.

  7. Mesenchymal stromal cells derived from cervical cancer produce high amounts of adenosine to suppress cytotoxic T lymphocyte functions. (United States)

    de Lourdes Mora-García, María; García-Rocha, Rosario; Morales-Ramírez, Omar; Montesinos, Juan José; Weiss-Steider, Benny; Hernández-Montes, Jorge; Ávila-Ibarra, Luis Roberto; Don-López, Christian Azucena; Velasco-Velázquez, Marco Antonio; Gutiérrez-Serrano, Vianey; Monroy-García, Alberto


    In recent years, immunomodulatory mechanisms of mesenchymal stem/stromal cells (MSCs) from bone marrow and other "classic" sources have been described. However, the phenotypic and functional properties of tumor MSCs are poorly understood. The aim of this study was to analyze the immunosuppressive capacity of cervical cancer-derived MSCs (CeCa-MSCs) on effector T lymphocytes through the purinergic pathway. We determined the expression and functional activity of the membrane-associated ectonucleotidases CD39 and CD73 on CeCa-MSCs and normal cervical tissue-derived MSCs (NCx-MSCs). We also analyzed their immunosuppressive capacity to decrease proliferation, activation and effector cytotoxic T (CD8+) lymphocyte function through the generation of adenosine (Ado). We detected that CeCa-MSCs express higher levels of CD39 and CD73 ectonucleotidases in cell membranes compared to NCx-MSCs, and that this feature was associated with the ability to strongly suppress the proliferation, activation and effector functions of cytotoxic T-cells through the generation of large amounts of Ado from the hydrolysis of ATP, ADP and AMP nucleotides. This study suggests that CeCa-MSCs play an important role in the suppression of the anti-tumor immune response in CeCa through the purinergic pathway.

  8. Lymphocyte respiration in children with Trisomy 21

    Directory of Open Access Journals (Sweden)

    Aburawi Elhadi H


    Full Text Available Abstract Background This study measured lymphocyte mitochondrial O2 consumption (cellular respiration in children with trisomy 21. Methods Peripheral blood mononuclear cells were isolated from whole blood of trisomy 21 and control children and these cells were immediately used to measure cellular respiration rate. [O2] was determined as a function of time from the phosphorescence decay rates (1/τ of Pd (II-meso-tetra-(4-sulfonatophenyl-tetrabenzoporphyrin. In sealed vials containing lymphocytes and glucose as a respiratory substrate, [O2] declined linearly with time, confirming the zero-order kinetics of O2 conversion to H2O by cytochrome oxidase. The rate of respiration (k, in μM O2 min-1, thus, was the negative of the slope of [O2] vs. time. Cyanide inhibited O2 consumption, confirming that oxidation occurred in the mitochondrial respiratory chain. Results For control children (age = 8.8 ± 5.6 years, n = 26, the mean (± SD value of kc (in μM O2 per min per 107 cells was 1.36 ± 0.79 (coefficient of variation, Cv = 58%; median = 1.17; range = 0.60 to 3.12; -2SD = 0.61. For children with trisomy 21 (age = 7.2 ± 4.6 years, n = 26, the values of kc were 0.82 ± 0.62 (Cv = 76%; median = 0.60; range = 0.20 to 2.80, pp6.1 mU/L. Fourteen of 26 (54% children with trisomy 21 had kc values of 0.20 to 0.60 (i.e., kc positively correlated with body-mass index (BMI, R >0.302, serum creatinine (R >0.507, blood urea nitrogen (BUN, R >0.535 and albumin (R >0.446. Conclusions Children with trisomy 21 in this study have reduced lymphocyte bioenergetics. The clinical importance of this finding requires further studies.

  9. Advertising Content


    Simon P. Anderson; Régis Renault


    Empirical evidence suggests that most advertisements contain little direct informa- tion. Many do not mention prices. We analyze a firm'ss choice of advertising content and the information disclosed to consumers. A firm advertises only product informa- tion, price information, or both; and prefers to convey only limited product information if possible. Extending the "persuasion" game, we show that quality information takes precedence over price information and horizontal product information.T...

  10. Non-bilayer structures in mitochondrial membranes regulate ATP synthase activity. (United States)

    Gasanov, Sardar E; Kim, Aleksandr A; Yaguzhinsky, Lev S; Dagda, Ruben K


    Cardiolipin (CL) is an anionic phospholipid at the inner mitochondrial membrane (IMM) that facilitates the formation of transient non-bilayer (non-lamellar) structures to maintain mitochondrial integrity. CL modulates mitochondrial functions including ATP synthesis. However, the biophysical mechanisms by which CL generates non-lamellar structures and the extent to which these structures contribute to ATP synthesis remain unknown. We hypothesized that CL and ATP synthase facilitate the formation of non-bilayer structures at the IMM to stimulate ATP synthesis. By using 1 H NMR and 31 P NMR techniques, we observed that increasing the temperature (8°C to 37°C), lowering the pH (3.0), or incubating intact mitochondria with CTII - an IMM-targeted toxin that increases the formation of immobilized non-bilayer structures - elevated the formation of non-bilayer structures to stimulate ATP synthesis. The F 0 sector of the ATP synthase complex can facilitate the formation of non-bilayer structures as incubating model membranes enriched with IMM-specific phospholipids with exogenous DCCD-binding protein of the F 0 sector (DCCD-BPF) elevated the formation of immobilized non-bilayer structures to a similar manner as CTII. Native PAGE assays revealed that CL, but not other anionic phospholipids, specifically binds to DCCD-BPF to promote the formation of stable lipid-protein complexes. Mechanistically, molecular docking studies identified two lipid binding sites for CL in DCCD-BPF. We propose a new model of ATP synthase regulation in which CL mediates the formation of non-bilayer structures that serve to cluster protons and ATP synthase complexes as a mechanism to enhance proton translocation to the F 0 sector, and thereby increase ATP synthesis. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Unexpected role of the copper transporter ATP7A in PDGF-induced vascular smooth

    Energy Technology Data Exchange (ETDEWEB)

    Ashino, T.; Varadarajan, S.; Urao, N.; Oshikawa, J.; Chen, G. -F.; Wang, H.; Huo, Y.; Finney, L.; Vogt, S.; McKinney, R. D.; Maryon, E. B.; Kaplan, J. H.; Ushio-Fukai, M.; Fukai, T. (Biosciences Division); ( XSD); ( PSC-USR); (Univ. of Illinois at Chicago); (Univ. of Minnesota)


    Copper, an essential nutrient, has been implicated in vascular remodeling and atherosclerosis with unknown mechanism. Bioavailability of intracellular copper is regulated not only by the copper importer CTR1 (copper transporter 1) but also by the copper exporter ATP7A (Menkes ATPase), whose function is achieved through copper-dependent translocation from trans-Golgi network (TGN). Platelet-derived growth factor (PDGF) promotes vascular smooth muscle cell (VSMC) migration, a key component of neointimal formation. To determine the role of copper transporter ATP7A in PDGF-induced VSMC migration. Depletion of ATP7A inhibited VSMC migration in response to PDGF or wound scratch in a CTR1/copper-dependent manner. PDGF stimulation promoted ATP7A translocation from the TGN to lipid rafts, which localized at the leading edge, where it colocalized with PDGF receptor and Rac1, in migrating VSMCs. Mechanistically, ATP7A small interfering RNA or CTR small interfering RNA prevented PDGF-induced Rac1 translocation to the leading edge, thereby inhibiting lamellipodia formation. In addition, ATP7A depletion prevented a PDGF-induced decrease in copper level and secretory copper enzyme precursor prolysyl oxidase (Pro-LOX) in lipid raft fraction, as well as PDGF-induced increase in LOX activity. In vivo, ATP7A expression was markedly increased and copper accumulation was observed by synchrotron-based x-ray fluorescence microscopy at neointimal VSMCs in wire injury model. These findings suggest that ATP7A plays an important role in copper-dependent PDGF-stimulated VSMC migration via recruiting Rac1 to lipid rafts at the leading edge, as well as regulating LOX activity. This may contribute to neointimal formation after vascular injury. Our findings provide insight into ATP7A as a novel therapeutic target for vascular remodeling and atherosclerosis.

  12. Decline of Phosphotransfer and Substrate Supply Metabolic Circuits Hinders ATP Cycling in Aging Myocardium.

    Directory of Open Access Journals (Sweden)

    Emirhan Nemutlu

    Full Text Available Integration of mitochondria with cytosolic ATP-consuming/ATP-sensing and substrate supply processes is critical for muscle bioenergetics and electrical activity. Whether age-dependent muscle weakness and increased electrical instability depends on perturbations in cellular energetic circuits is unknown. To define energetic remodeling of aged atrial myocardium we tracked dynamics of ATP synthesis-utilization, substrate supply, and phosphotransfer circuits through adenylate kinase (AK, creatine kinase (CK, and glycolytic/glycogenolytic pathways using 18O stable isotope-based phosphometabolomic technology. Samples of intact atrial myocardium from adult and aged rats were subjected to 18O-labeling procedure at resting basal state, and analyzed using the 18O-assisted HPLC-GC/MS technique. Characteristics for aging atria were lower inorganic phosphate Pi[18O], γ-ATP[18O], β-ADP[18O], and creatine phosphate CrP[18O] 18O-labeling rates indicating diminished ATP utilization-synthesis and AK and CK phosphotransfer fluxes. Shift in dynamics of glycolytic phosphotransfer was reflected in the diminished G6P[18O] turnover with relatively constant glycogenolytic flux or G1P[18O] 18O-labeling. Labeling of G3P[18O], an indicator of G3P-shuttle activity and substrate supply to mitochondria, was depressed in aged myocardium. Aged atrial myocardium displayed reduced incorporation of 18O into second (18O2, third (18O3, and fourth (18O4 positions of Pi[18O] and a lower Pi[18O]/γ-ATP[18 O]-labeling ratio, indicating delayed energetic communication and ATP cycling between mitochondria and cellular ATPases. Adrenergic stress alleviated diminished CK flux, AK catalyzed β-ATP turnover and energetic communication in aging atria. Thus, 18O-assisted phosphometabolomics uncovered simultaneous phosphotransfer through AK, CK, and glycolytic pathways and G3P substrate shuttle deficits hindering energetic communication and ATP cycling, which may underlie energetic

  13. Assembly of the membrane domain of ATP synthase in human mitochondria. (United States)

    He, Jiuya; Ford, Holly C; Carroll, Joe; Douglas, Corsten; Gonzales, Evvia; Ding, Shujing; Fearnley, Ian M; Walker, John E


    The ATP synthase in human mitochondria is a membrane-bound assembly of 29 proteins of 18 kinds. All but two membrane components are encoded in nuclear genes, synthesized on cytoplasmic ribosomes, and imported into the matrix of the organelle, where they are assembled into the complex with ATP6 and ATP8, the products of overlapping genes in mitochondrial DNA. Disruption of individual human genes for the nuclear-encoded subunits in the membrane portion of the enzyme leads to the formation of intermediate vestigial ATPase complexes that provide a description of the pathway of assembly of the membrane domain. The key intermediate complex consists of the F 1 -c 8 complex inhibited by the ATPase inhibitor protein IF 1 and attached to the peripheral stalk, with subunits e, f, and g associated with the membrane domain of the peripheral stalk. This intermediate provides the template for insertion of ATP6 and ATP8, which are synthesized on mitochondrial ribosomes. Their association with the complex is stabilized by addition of the 6.8 proteolipid, and the complex is coupled to ATP synthesis at this point. A structure of the dimeric yeast F o membrane domain is consistent with this model of assembly. The human 6.8 proteolipid (yeast j subunit) locks ATP6 and ATP8 into the membrane assembly, and the monomeric complexes then dimerize via interactions between ATP6 subunits and between 6.8 proteolipids (j subunits). The dimers are linked together back-to-face by DAPIT (diabetes-associated protein in insulin-sensitive tissue; yeast subunit k), forming long oligomers along the edges of the cristae.

  14. ATP8B1 requires an accessory protein for endoplasmic reticulum exit and plasma membrane lipid flippase activity

    NARCIS (Netherlands)

    Paulusma, Coen C.; Folmer, Dineke E.; Ho-Mok, Kam S.; de Waart, D. Rudi; Hilarius, Petra M.; Verhoeven, Arthur J.; Oude Elferink, Ronald P. J.


    Mutations in ATP8B1 cause progressive familial intrahepatic cholestasis type 1 and benign recurrent intrahepatic cholestasis type 1. Previously, we have shown in mice that Atp8b1 deficiency leads to enhanced biliary excretion of phosphatidylserine, and we hypothesized that ATP8B1 is a flippase for

  15. Double-lock ratchet mechanism revealing the role of  SER-344 in FoF1 ATP synthase

    KAUST Repository

    Beke-Somfai, T.; Lincoln, P.; Norden, B.


    In a majority of living organisms, FoF1 ATP synthase performs the fundamental process of ATP synthesis. Despite the simple net reaction formula, ADP+Pi→ATP+H2O, the detailed step-by-step mechanism of the reaction yet remains to be resolved owing

  16. Visualization of ATP release in pancreatic acini in response to cholinergic stimulus. Use of fluorescent probes and confocal microscopy

    DEFF Research Database (Denmark)

    Sørensen, Christiane Elisabeth; Novak, Ivana


    of this reaction in confocal microscopy, we monitored luciferin fluorescence as a sign of ATP release by single acini. In addition we used quinacrine to mark ATP stores, which were similar to those marked with fluorescent ATP, 2'-(or-3')-O-(N-methylanthraniloyl) adenosine 5'-triphosphate, but only partially...

  17. The requirement of matrix ATP for the import of precursor proteins into the mitochondrial matrix and intermembrane space

    NARCIS (Netherlands)

    Stuart, Rosemary A.; Gruhler, Albrecht; Klei, Ida van der; Guiard, Bernard; Koll, Hans; Neupert, Walter


    The role of ATP in the matrix for the import of precursor proteins into the various mitochondrial subcompartments was investigated by studying protein translocation at experimentally defined ATP levels. Proteins targeted to the matrix were neither imported or processed when matrix ATP was depleted.

  18. The role of the C8 proton of ATP in the regulation of phosphoryl transfer within kinases and synthetases

    CSIR Research Space (South Africa)

    Kenyon, CP


    Full Text Available Kinase and synthetase enzymes utilise C8D-ATP in preference to non-deuterated ATP. The KIE obtained at low ATP concentrations is clearly a primary KIE demonstrating strong evidence that the bond to the isotopically substituted hydrogen is being...

  19. Mitochondrial DNA copy number and chronic lymphocytic leukemia/small lymphocytic lymphoma risk in two prospective studies

    NARCIS (Netherlands)

    Kim, Christopher; Bassig, Bryan A; Seow, Wei Jie; Hu, Wei; Purdue, Mark P; Huang, Wen-Yi; Liu, Chin-San; Cheng, Wen-Ling; Männistö, Satu; Vermeulen, Roel; Weinstein, Stephanie J; Lim, Unhee; Hosgood, H Dean; Bonner, Matthew R; Caporaso, Neil E; Albanes, Demetrius; Lan, Qing; Rothman, Nathaniel

    BACKGROUND: Mitochondrial DNA copy number (mtDNA CN) may be modified by mitochondria in response to oxidative stress. Previously, mtDNA CN was associated with non-Hodgkin lymphoma (NHL) risk, particularly chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). We conducted a replication

  20. 2SNP heritability and effects of genetic variants for neutrophil-to-lymphocyte and platelet-to-lymphocyte ratio

    NARCIS (Netherlands)

    Lin, Bochao Danae; Carnero-Montoro, Elena; Bell, Jordana T; Boomsma, Dorret I; de Geus, Eco J; Jansen, Rick; Kluft, Cornelis; Mangino, Massimo; Penninx, Brenda; Spector, Tim D; Willemsen, Gonneke; Hottenga, Jouke-Jan


    Neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) are important biomarkers for disease development and progression. To gain insight into the genetic causes of variance in NLR and PLR in the general population, we conducted genome-wide association (GWA) analyses and

  1. Selective effects of alpha interferon on human T-lymphocyte subsets during mixed lymphocyte cultures

    DEFF Research Database (Denmark)

    Hokland, M; Hokland, P; Heron, I


    Mixed lymphocyte reaction (MLR) cultures of human lymphocyte subsets with or without the addition of physiological doses of human alpha interferon (IFN-alpha) were compared with respect to surface marker phenotypes and proliferative capacities of the responder cells. A selective depression on the T...... T4 cells and decreased numbers of T4 cells harvested from IFN MLRs (days 5-6 of culture). In contrast, it was shown that the T8 (cytotoxic/suppressor) subset in MLRs was either not affected or slightly stimulated by the addition of IFN. The depression of the T4 cells by IFN was accompanied...... by a decrease in the number of activated T cells expressing Ia antigens. On the other hand, IFN MLRs contained greater numbers of cells expressing the T10 differentiation antigen. In experiments with purified T-cell subsets the IFN effect was exerted directly on the T4 cells and not mediated by either T8...

  2. Extracellular Adenosine Triphosphate Associated with Amphibian Erythrocytes: Inhibition of ATP Release by Anion Channel Blockers. (United States)


    Paddle and Burnstock (326), Williams and Forrester (463), Forrester and Williams (151) and Clemens and Forrester (82) provide evidence that hypoxia ATp4 - receptor. Fed. Proc. 45:208, 1986. (abstr) 99. Dahlen , S.E. and Hedqvist, P. ATP, B,y-methylene ATP andN adenosine inhibit non-cholinergic...regulation of skeletal muscle blood low. Circ Res. 29:375-384, 1971. 117. Dodd, J., Jahr, C.E., Hamilton, P.N., Heath, M.J., Matthew , W.P., and Jessell, T.M

  3. Modulation of Central Synapses by Astrocyte-Released ATP and Postsynaptic P2X Receptors (United States)

    Pankratov, Yuriy


    Communication between neuronal and glial cells is important for neural plasticity. P2X receptors are ATP-gated cation channels widely expressed in the brain where they mediate action of extracellular ATP released by neurons and/or glia. Recent data show that postsynaptic P2X receptors underlie slow neuromodulatory actions rather than fast synaptic transmission at brain synapses. Here, we review these findings with a particular focus on the release of ATP by astrocytes and the diversity of postsynaptic P2X-mediated modulation of synaptic strength and plasticity in the CNS. PMID:28845311

  4. ATP-gamma-S shifts the operating point of outer hair cell transduction towards scala tympani. (United States)

    Bobbin, Richard P; Salt, Alec N


    ATP receptor agonists and antagonists alter cochlear mechanics as measured by changes in distortion product otoacoustic emissions (DPOAE). Some of the effects on DPOAEs are consistent with the hypothesis that ATP affects mechano-electrical transduction and the operating point of the outer hair cells (OHCs). This hypothesis was tested by monitoring the effect of ATP-gamma-S on the operating point of the OHCs. Guinea pigs anesthetized with urethane and with sectioned middle ear muscles were used. The cochlear microphonic (CM) was recorded differentially (scala vestibuli referenced to scala tympani) across the basal turn before and after perfusion (20 min) of the perilymph compartment with artificial perilymph (AP) and ATP-gamma-S dissolved in AP. The operating point was derived from the cochlear microphonics (CM) recorded in response low frequency (200 Hz) tones at high level (106, 112 and 118 dB SPL). The analysis procedure used a Boltzmann function to simulate the CM waveform and the Boltzmann parameters were adjusted to best-fit the calculated waveform to the CM. Compared to the initial perfusion with AP, ATP-gamma-S (333 microM) enhanced peak clipping of the positive peak of the CM (that occurs during organ of Corti displacements towards scala tympani), which was in keeping with ATP-induced displacement of the transducer towards scala tympani. CM waveform analysis quantified the degree of displacement and showed that the changes were consistent with the stimulus being centered on a different region of the transducer curve. The change of operating point meant that the stimulus was applied to a region of the transducer curve where there was greater saturation of the output on excursions towards scala tympani and less saturation towards scala vestibuli. A significant degree of recovery of the operating point was observed after washing with AP. Dose response curves generated by perfusing ATP-gamma-S (333 microM) in a cumulative manner yielded an EC(50) of 19.8 micro

  5. GTP plus water mimics ATP in the active site of protein kianse CK2

    DEFF Research Database (Denmark)

    Niefind, K; Pütter, M; Guerra, B


    The structures of the catalytic subunit of protein kinase CK2 from Zea mays complexed with Mg2+ and with analogs of ATP or GTP were determined to 2.2 A resolution. Unlike most other protein kinases, CK2 from various sources shows 'dual-cosubstrate specificity', that is, the ability to efficiently...... use either ATP or GTP as a cosubstrate. The structures of these complexes demonstrate that water molecules are critical to switch the active site of CK2 from an ATP- to a GTP-compatible state. An understanding of the structural basis of dual-cosubstrate specificity may help in the design of drugs...

  6. Modulation of Central Synapses by Astrocyte-Released ATP and Postsynaptic P2X Receptors

    Directory of Open Access Journals (Sweden)

    Eric Boué-Grabot


    Full Text Available Communication between neuronal and glial cells is important for neural plasticity. P2X receptors are ATP-gated cation channels widely expressed in the brain where they mediate action of extracellular ATP released by neurons and/or glia. Recent data show that postsynaptic P2X receptors underlie slow neuromodulatory actions rather than fast synaptic transmission at brain synapses. Here, we review these findings with a particular focus on the release of ATP by astrocytes and the diversity of postsynaptic P2X-mediated modulation of synaptic strength and plasticity in the CNS.

  7. Structural Basis for Specific Inhibition of tRNA Synthetase by an ATP Competitive Inhibitor


    Fang, Pengfei; Han, Hongyan; Wang, Jing; Chen, Kaige; Chen, Xin; Guo, Min


    Pharmaceutical inhibitors of aminoacyl-tRNA synthetases demand high species and family specificity. The antimalarial ATP-mimetic cladosporin selectively inhibits P. falciparum LysRS (PfLysRS). How the binding to a universal ATP site achieves the specificity is unknown. Here we report 3 crystal structures of cladosporin with human LysRS, PfLysRS, and a Pf-like human LysRS mutant. In all 3 structures, cladosporin occupies the class defining ATP-binding pocket, replacing the adenosine portion of...

  8. Minimal residual disease in chronic lymphocytic leukaemia. (United States)

    García Vela, José Antonio; García Marco, José Antonio


    Minimal residual disease (MRD) assessment is an important endpoint in the treatment of chronic lymphocytic leukaemia (CLL). It is highly predictive of prolonged progression-free survival (PFS) and overall survival and could be considered a surrogate for PFS in the context of chemoimmunotherapy based treatment. Evaluation of MRD level by flow cytometry or molecular techniques in the era of the new BCR and Bcl-2 targeted inhibitors could identify the most cost-effective and durable treatment sequencing. A therapeutic approach guided by the level of MRD might also determine which patients would benefit from an early stop or consolidation therapy. In this review, we discuss the different MRD methods of analysis, which source of tumour samples must be analysed, the future role of the detection of circulating tumour DNA, and the potential role of MRD negativity in clinical practice in the modern era of CLL therapy. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

  9. Lymphocytic nucleolar index in the combined application

    Energy Technology Data Exchange (ETDEWEB)

    Kilyovska, M.; Nechev, Kh.; Vankova, P.; Tsvetkov, P.; Shopova, V. (Meditsinski Fakultet, Pleven (Bulgaria). Katedra Mediko-Sanitarna Zashtita)


    Sex mature male rats were irradiated with 5,25 and 50 rad from X-ray source. One group of irradiated animals was treated intraperitoneally with 10 mCi/animal Ce/sup 144/ or 0.04 mCi/g Sr/sup 89/. The second group was treated only with radionuclide. The nucleolar index (NI) of the lymphocytes in a blood smear was studied on the 1st, 3rd, 8th and 30th day after application. It was found that X-irradiation increased the value of NI after the 15th day, the effect being independent on the dose rates. Ce/sup 144/, applied alone in combination with external irradiation, also causes an increase of NI. Combined application of Sr/sup 89/ and external irradiation leads after one month to a decrease of NI. The results are discussed in connection with radionuclide kinetics and dose distribution.

  10. Predictive radiosensitivity tests in human lymphocytes

    International Nuclear Information System (INIS)

    Di Giorgio, Marina; Vallerga, Maria B.; Taja, Maria R.; Sardi, M.; Busto, E.; Mairal, L.; Roth, B.; Menendez, P.; Bonomi, M.


    Individual radiosensitivity is an inherent characteristic, associated with an abnormally increased reaction to ionising radiation of both the whole body and cells derived from body tissues. Human population is not uniform in its radiation sensitivity. Radiosensitive sub-groups exist, which would suffer an increased incidence of both deterministic and stochastic effects. Clinical studies have suggested that a large part of the spectrum of normal tissue reaction may be due to differences in individual radiosensitivity. The identification of such sub-groups should be relevant for radiation therapy and radiation protection purposes. It is suggested that DNA repair mechanisms are involved. Consequently, the characterization of DNA repair in lymphocytes through cytokinesis blocked micronucleus (MN) and alkaline single-cell microgel electrophoresis (comet) assays could be a suitable approache to evaluate individual radiosensitivity in vitro. The aims of this study were: 1) To assess the in vitro radiosensitivity of peripheral blood lymphocytes from two groups of cancer patients (prospectively and retrospectively studied), using MN and comet assays, in comparison with the clinical radiation reaction and 2) To test the predictive potential of both techniques for the identification of radiosensitivity sub-groups. 38 cancer patients receiving radiation therapy were enrolled in this study. 19 patients were evaluated prior, mid-way and on completion of treatment (prospective group) and 19 patients were evaluated about 6-18 month after radiotherapy (retrospective group). Cytogenetic data from the prospective group were analysed using a mathematical model to evaluate the attenuation of the cytogenetic effect as a function of the time between a single exposure and blood sampling, estimating a cytogenetic recovery factor k. In the retrospective group, blood samples were irradiated in vitro with 0 (control) or 2 Gy and evaluated using MN test. Cytogenetic data were analysed

  11. Sudden unexpected death associated with lymphocytic thyroiditis

    DEFF Research Database (Denmark)

    Vestergaard, Vibeke; Drostrup, Dorthe Høj; Thomsen, Jørgen L


    A forensic autopsy study comprising 125 cases was carried out retrospectively in order to evaluate pathological changes in the thyroid gland in different groups of death. The five groups selected consecutively were: (i) opiate addicts who died from an overdose, (ii) alcoholics who died as a result...... of their alcohol abuse, (iii) cases of fatal poisoning other than opiate addicts, (iv) unknown cause of death and (v) controls without prior disease. Tissue samples from the thyroid gland were cut and stained with haematoxylin and eosin and van Gieson. Histology examinations were subsequently performed blind...... infiltration of the thyroid parenchyma in five of the 124 cases, of which four belonged in the group of 'unknown cause of death'. This discovery leads to reflections regarding lymphocytic thyroiditis as a cause of death, either by itself or in combination with other disorders. Silent (painless) thyroiditis...

  12. [Lymphocyte metabolism in children with extensive burns]. (United States)

    Artem'ev, S A; Nazarov, I P; Kamzalakova, N I; Bulygin, G V


    The results of the study lead to the conclusion that the development of burn disease in children is accompanied by significant lymphocytic structural metabolic changes that determine the functional capabilities of cells and the immune system as a whole. There is an evident activation of the glutathione antioxidant system, a drastic activation of enzymes that ensure Krebs cycle reactions, as well as activation of anaerobic processes. The above changes are mainly caused by the activated sympathoadrenal system that is characteristic of stresses. The knowledge about the metabolic mechanisms responsible for the development of cellular reactions to burn shock and burn disease permits specification of the elements of the pathogenesis of these severe conditions and substantiation of the possibility of using metabolic correction in the complex treatment of children with the above pathology.

  13. Ibrutinib: A Review in Chronic Lymphocytic Leukaemia. (United States)

    Deeks, Emma D


    Ibrutinib (Imbruvica ® ) is an oral irreversible inhibitor of Bruton's tyrosine kinase, a B-cell receptor (BCR) signalling kinase expressed by various haematopoietic cells, B-cell lymphomas and leukaemias. The drug is indicated for the treatment of certain haematological malignancies, including chronic lymphocytic leukaemia (CLL)/small lymphocytic lymphoma (SLL), which are the focus of this review. In phase III CLL/SLL trials, ibrutinib monotherapy was more effective than chlorambucil in the first-line treatment of elderly patients (RESONATE-2) and more effective than ofatumumab in previously-treated adults (RESONATE). Likewise, a combination of ibrutinib, bendamustine and rituximab was more effective in previously-treated adults than bendamustine plus rituximab in a phase III placebo-controlled study (HELIOS). These ibrutinib regimens were associated with significantly better progression-free survival, overall response rates, and overall survival than the comparators (in protocol-specified or planned analyses), with ibrutinib therapy providing benefit regardless of adverse prognostic factors, such as del(17p)/TP53 mutation and del(11q). Ibrutinib has an acceptable tolerability profile, although certain adverse events (e.g. bleeding and atrial fibrillation) require consideration. Redistribution lymphocytosis can occur, but is not indicative of disease progression. Although longer-term data would be beneficial, ibrutinib is a welcome treatment option for patients with CLL, including those who have higher-risk disease or are less physically fit. Indeed, current EU and US guidelines recommend/prefer the drug for the first- and/or subsequent-line treatment of certain patients, including those with del(17p)/TP53 mutation.

  14. Pretreatment with quercetin prevents changes in lymphocytes E-NTPDase/E-ADA activities and cytokines secretion in hyperlipidemic rats. (United States)

    Braun, Josiane B S; Ruchel, Jader B; Manzoni, Alessandra G; Abdalla, Fátima H; Casalli, Emerson A; Castilhos, Lívia G; Passos, Daniela F; Leal, Daniela B R


    Hyperlipidemia (HL) is a condition associated with endothelial dysfunction and inflammatory disorders. Purinergic system ectoenzymes play an important role in modulating the inflammatory and immune response. This study investigated whether the preventive treatment with quercetin is able to prevent changes caused by hyperlipidemia in the purinergic system, through the activities of E-NTPDase and E-ADA in lymphocytes, and quantify the nucleotides and nucleoside, and the secretion of anti- and proinflammatory cytokines. Animals were divided into saline/control, saline/quercetin 5 mg/kg, saline/quercetin 25 mg/kg, saline/quercetin 50 mg/kg, saline/simvastatin (0.04 mg/kg), hyperlipidemia, hyperlipidemia/quercetin 5 mg/kg, hyperlipidemia/quercetin 25 mg/kg, hyperlipidemia/quercetin 50 mg/kg, and hyperlipidemia/simvastatin. Animals were pretreated with quercetin for 30 days and hyperlipidemia was subsequently induced by intraperitoneal administration of 500 mg/kg of poloxamer-407. Simvastatin was administered after the induction of hyperlipidemia. Lymphocytes were isolated and E-NTPDase and E-ADA activities were determined. Serum was separated for the cytokines and nucleotide/nucleoside quantification. E-NTPDase and E-ADA activities were increased in lymphocytes from hyperlipidemic rats and pretreatment with quercetin was able to prevent the increase in the activities of these enzymes caused by hyperlipidemia. Hyperlipidemic rats when receiving pretreatment with quercetin and treatment with simvastatin showed decreased levels of ATP and ADP when compared to the untreated hyperlipidemic group. The IFN-γ and IL-4 cytokines were increased in the hyperlipidemic group when compared with control group, and decreased when hyperlipidemic rats received the pretreatment with quercetin. However, pretreatment with quercetin was able to prevent the alterations caused by hyperlipidemia probably by regulating the inflammatory process. We can suggest that the quercetin is a

  15. Stimulation by ATP of proinsulin to insulin conversion in isolated rat pancreatic islet secretory granules. Association with the ATP-dependent proton pump

    International Nuclear Information System (INIS)

    Rhodes, C.J.; Lucas, C.A.; Mutkoski, R.L.; Orci, L.; Halban, P.A.


    Isolated rat pancreatic islets were pulse-labeled for 5 min with [ 3 H]leucine then chased for 25 min, during which time endogenously labeled [ 3 H]proinsulin becomes predominantly compartmented in immature secretory granules. The islets were then homogenized in isotonic sucrose (pH 7.4) and a beta-granule preparation obtained by differential centrifugation and discontinuous sucrose gradient ultracentrifugation. This preparation was enriched 8-fold in beta-granules. Aside from contamination with mitochondria and a limited number of lysosomes, the beta-granule preparation was essentially free of any other organelles involved in proinsulin synthesis and packaging (i.e. microsomal elements and, more particularly, Golgi complex). Conversion of endogenously labeled [ 3 H]proinsulin was followed in this beta-granule fraction for up to 2 h at 37 degrees C in a buffer (pH 7.3) that mimicked the cationic constituents of B-cell cytosol, during which time 92% of the beta-granules remained intact. Proinsulin conversion was analyzed by high performance liquid chromatography. The rate of proinsulin conversion to insulin was stimulated by 2.2 +/- 0.1-fold (n = 6) (at a 60-min incubation) in the presence of ATP (2 mM) and an ATP regenerating system compared to beta-granule preparations incubated without ATP. This ATP stimulation was abolished in the presence of beta-granule proton pump ATPase inhibitors (tributyltin, 2.5 microM, or 1,3-dicyclohexylcarbodiimide, 50 microM). Inhibitors of mitochondrial proton pump ATPases had no effect on the ATP stimulation of proinsulin conversion. When granules were incubated in a more acidic buffer, proinsulin conversion was increased relative to that at pH 7.3. At pH 5.5, ATP no longer stimulated conversion, and tributyltin and 1,3-dicyclohexylcarbodiimide had no effect

  16. Sickle cell anemia induces changes in peripheral lymphocytes E-NTPDase/E-ADA activities and cytokines secretion in patients under treatment. (United States)

    Castilhos, Lívia G; Doleski, Pedro H; Bertoldo, Tatiana M D; Passos, Daniela F; Bertoncheli, Claudia de M; Rezer, João F P; Schlemmer, Josiane B; Leal, Daniela B R


    Sickle cell anemia (SCA) is characterized by hemoglobin polymerization that results in sickle-shaped red blood cells. The vascular obstruction by sickle erythrocytes is often inflammatory, and purinergic system ecto-enzymes play an important role in modulating the inflammatory and immune response. This study aimed to evaluate the E-NTPDase and E-ADA activities in lymphocytes of SCA treated patients, as well as verify the cytokine profile in this population. Fifteen SCA treated patients and 30 health subjects (control group) were selected. The peripheral lymphocytes were isolated and E-NTPDase and E-ADA activities were determined. Serum was separated from clot formation for the cytokines quantification. E-NTPDase (ATP and ADP as substrate) and E-ADA (adenosine as substrate) activities were increased in lymphocytes from SCA patients (PADA enzymes represent an important control of purine-mediated in the SCA disease, avoiding elevated adenosine levels in the extracellular medium and consequent organ injuries in these patients. The pro-inflammatory cytokines decreased levels by use of hydroxyurea occur in attempt to reduce the pro-inflammatory response and prevent vaso-oclusive crisis. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  17. Effect of postirradiation anoxia on radiosensitivity of lymphocytes

    International Nuclear Information System (INIS)

    Schrek, R.


    Radiosensitivity was measured by viable-lymphocyte counts and by uridine uptake. The viability of the lymphocytes was based on morphologic characteristics visualized by phase contrast microscopy of the cells in a special slide chamber. Low doses of x rays (10 to 1000 R) and incubation at 37 0 C killed lymphocytes in interphase with the production of pyknotic nuclei (nuclear death), and large doses (6000 R) produced nuclei with clear nucleoplasm (cytoplasmic death). Nuclear, but not cytoplasmic, death was inhibited by incubation of the irradiated cells at 27 0 C. Postirradiation anoxia had no effect on development of the nuclear and cytoplasmic death of lymphocytes irradiated with 100 to 6000 R. Anoxia had no effect on the early response of lymphocytes to phytohemagglutinin (PHA) [increase in ribonucleic acid (RNA) and protein synthesis] but inhibited completely the late effects [increase in deoxyribonucleic acid (DNA) synthesis and transformation into lymphoblastoid cells]. The PHA caused relative radioresistance of lymphocytes under aerobic conditions and, to a lesser extent, under anaerobic conditions. The slight radioresistance induced by PHA in anoxic lymphocytes apparently did not depend on an increase in DNA synthesis or on the transformation to lymphoblastoid cells

  18. Role of ATP binding and hydrolysis in the gating of the cystic fibrosis transmembrane conductance regulator

    Directory of Open Access Journals (Sweden)

    Taras Gout


    Full Text Available The CFTR gene is unique within the ATP-binding cassette (ABC protein family, predominantly of transporters, by coding a chloride channel. The gating mechanism of ABC proteins has been characterized by the ATP Switch model in terms cycles of dimer formation and dissociation linked to ATP binding and hydrolysis, respectively. It would be of interest to assess the extent that Cystic Fibrosis Transmembrane Conductance Regulator (CFTR, a functional channel, fits the ATP Switch model for ABC transporters. Additional transporter mechanisms, namely those of Pgp and HlyB, are discussed for perspective. Literature search of databases selected key references in comparing and contrasting the gating mechanism. CFTR is a functional chloride channel facilitating transmembrane anion flow down electrochemical gradients. A dysfunctional CFTR protein results in cystic fibrosis, a fatal pleiotropic disease currently managed symptomatically. Understanding the gating mechanism will help target drug development aimed at alleviating and curing the disease.

  19. Functional expression of a heterologous nickel-dependent, ATP-independent urease in Saccharomyces cerevisiae

    NARCIS (Netherlands)

    Milne, N.; Luttik, M.A.H.; Cueto Rojas, H.F.; Wahl, A.; Van Maris, A.J.A.; Pronk, J.T.; Daran, J.G.


    In microbial processes for production of proteins, biomass and nitrogen-containing commodity chemicals, ATP requirements for nitrogen assimilation affect product yields on the energy producing substrate. In Saccharomyces cerevisiae, a current host for heterologous protein production and potential

  20. Tissue-specific alternative splicing and expression of ATP1B2 gene

    African Journals Online (AJOL)



    May 15, 2012 ... retention; these isoforms were found in liver, kidney, muscle and breast tissues. ... lower levels than the complete ATP1B2 gene transcript in all the ... temperature. ... growth, differentiation, and disease (Zhou et al., 2002;.

  1. Development of the simple evaluation method of the soil biomass by the ATP measurement

    Czech Academy of Sciences Publication Activity Database

    Urashima, Y.; Nakajima, M.; Kaneda, Satoshi; Murakami, T.


    Roč. 78, č. 2 (2007), s. 187-190 ISSN 0029-0610 Institutional research plan: CEZ:AV0Z60660521 Keywords : simple evaluation method * soil biomass * ATP measurement Subject RIV: EH - Ecology, Behaviour

  2. Studies on luciferin-luciferase ATP assay in plants (etiolated wheat germs, and bean leaves

    Directory of Open Access Journals (Sweden)

    A. Barbaro


    Full Text Available For ATP determination by the method of bioluminescence apparatus of home production was adapted from the equipment available in any isotope laboratory. The measurement error did not exceed 1.5 per cent. Methodical experiments concerned the choice of the extraction, fixation and storage methods of plant material for determination at the given moment of the amount of ATP in the tissues, unchanged by the analytical procedure. The highest ATP amounts were recovered by extraction with perchloric acid at high (25% concentrations of the tissue in the homogenate. The best way of fixation of the material for later analyses was found to be freezing of ready extracts. Lyophilization and freezing of the plant material caused a several-fold decrease of the ATP level in the tissues. These results suggest the necessity of working in conditions of low temperature during the entire analytical procedure and strict observation of time limitation.

  3. Studies towards the synthesis of ATP analogs as potential glutamine synthetase inhibitors

    CSIR Research Space (South Africa)

    Salisu, S


    Full Text Available and Centre for Chemico- and Biomedicinal Research, Rhodes University, Grahamstown, South Africa b CSIR BIO/CHEMTEK, Modderfontein, South Africa ABSTRACT In research directed at the development of adenine triphosphate (ATP) analogs as potential...

  4. Detection of microbial contaminations in drinking water using ATP measurements – evaluating potential for online monitoring

    DEFF Research Database (Denmark)

    Vang, Óluva Karin; Corfitzen, Charlotte B.; Albrechtsen, Hans-Jørgen


    There is an increasing call for fast and reliable methods for continuous monitoring of microbial drinking water quality in order to protect public health. The potential for Adenosine triphosphate (ATP) measurements as a real-time analysis for continuous monitoring of microbial drinking water...... quality was investigated through simulation of two contamination scenarios, i.e. drinking water contaminated with waste water and surface water at various concentrations. With ATP measurements it was possible to detect waste water diluted 1000-10,000 times in drinking water depending on sensitivity...... of reagent kit. Surface water diluted 100-1000 times was detected in drinking water with ATP measurements. ATP has the potential as an early warning tool, especially in the period when the contamination concentration is high. 2011 © American Water Works Association AWWA WQTC Conference Proceedings All Rights...

  5. Increased level of extracellular ATP at tumor sites: in vivo imaging with plasma membrane luciferase.

    Directory of Open Access Journals (Sweden)

    Patrizia Pellegatti


    Full Text Available There is growing awareness that tumour cells build up a "self-advantageous" microenvironment that reduces effectiveness of anti-tumour immune response. While many different immunosuppressive mechanisms are likely to come into play, recent evidence suggests that extracellular adenosine acting at A2A receptors may have a major role in down-modulating the immune response as cancerous tissues contain elevated levels of adenosine and adenosine break-down products. While there is no doubt that all cells possess plasma membrane adenosine transporters that mediate adenosine uptake and may also allow its release, it is now clear that most of extracellularly-generated adenosine originates from the catabolism of extracellular ATP.Measurement of extracellular ATP is generally performed in cell supernatants by HPLC or soluble luciferin-luciferase assay, thus it generally turns out to be laborious and inaccurate. We have engineered a chimeric plasma membrane-targeted luciferase that allows in vivo real-time imaging of extracellular ATP. With this novel probe we have measured the ATP concentration within the tumour microenvironment of several experimentally-induced tumours.Our results show that ATP in the tumour interstitium is in the hundreds micromolar range, while it is basically undetectable in healthy tissues. Here we show that a chimeric plasma membrane-targeted luciferase allows in vivo detection of high extracellular ATP concentration at tumour sites. On the contrary, tumour-free tissues show undetectable extracellular ATP levels. Extracellular ATP may be crucial for the tumour not only as a stimulus for growth but also as a source of an immunosuppressive agent such as adenosine. Our approach offers a new tool for the investigation of the biochemical composition of tumour milieu and for development of novel therapies based on the modulation of extracellular purine-based signalling.

  6. High-altitude adaptation of Tibetan chicken from MT-COI and ATP-6 perspective. (United States)

    Zhao, Xiaoling; Wu, Nan; Zhu, Qing; Gaur, Uma; Gu, Ting; Li, Diyan


    The problem of hypoxia adaptation in high altitudes is an unsolved brainteaser in the field of life sciences. As one of the best chicken breeds with adaptability to highland environment, the Tibetan chicken, is genetically different from lowland chicken breeds. In order to gain a better understanding of the mechanism of hypoxic adaptability in high altitude, in the present study, we focused on the MT-COI together with ATP-6 gene to explore the regulatory mechanisms for hypoxia adaptability in Tibet chicken. Here, we sequenced MT-COI of 29 Tibetan chickens and 30 Chinese domestic chickens and ATP-6 gene of 28 Tibetan chickens and 29 Chinese domestic chickens. In MT-COI gene, 9 single nucleotide polymorphisms (SNPs) were detected though none of these was a missense mutation, confirming the fact that MT-COI gene is a largely conservative sequence. In ATP-6 gene, 6 single nucleotide polymorphisms (SNPs) were detected and we found a missense mutation (m.9441G > A) in the ATP-6 gene of Tibetan chicken resulting in an amino acid substitution. Due to the critical role of ATP-6 gene in the proton translocation and energy metabolism, we speculated the possibility of this mutation playing an important role in easier energy conversion and metabolism in Tibetan chickens than Chinese domestic chickens so as to better adapt to the harsh environment of the high-altitude areas. The Median-joining profile also suggested that haplotype Ha2 has the ancestral position to the other haplotypes and has significant relationship with high-altitude adaptation in ATP-6 gene. Therefore, we considered that the polymorphism (m.9441G > A) in the ATP-6 gene may affect the specific functions of ATP-6 enzyme relating to high-altitude adaptation of Tibetan chicken and MT-COI gene is a largely conservative sequence.

  7. Effect of Intramuscular Protons, Lactate, and ATP on Muscle Hyperalgesia in Rats.

    Directory of Open Access Journals (Sweden)

    Nicholas S Gregory

    Full Text Available Chronic muscle pain is a significant health problem leading to disability[1]. Muscle fatigue can exacerbate muscle pain. Metabolites, including ATP, lactate, and protons, are released during fatiguing exercise and produce pain in humans. These substances directly activate purinergic (P2X and acid sensing ion channels (ASICs on muscle nociceptors, and when combined, produce a greater increase in neuron firing than when given alone. Whether the enhanced effect of combining protons, lactate, and ATP is the sum of individual effects (additive or more than the sum of individual effects (synergistic is unknown. Using a rat model of muscle nociceptive behavior, we tested each of these compounds individually over a range of physiologic and supra-physiologic concentrations. Further, we combined all three compounds in a series of dilutions and tested their effect on muscle nociceptive behavior. We also tested a non-hydrolyzable form of ATP (α,β-meATP alone and in combination with lactate and acidic pH. Surprisingly, we found no dose-dependent effect on muscle nociceptive behavior for protons, lactate, or ATP when given alone. We similarly found no effect after application of each two-metabolite combination. Only pH 4 saline and α,β-meATP produced hyperalgesia when given alone. When all 3 substances were combined, however, ATP (2.4μm, lactate (10mM, and acidic pH (pH 6.0 produced an enhanced effect greater than the sum of the effects of the individual components, i.e. synergism. α,β me ATP (3nmol, on the other hand, showed no enhanced effects when combined with lactate (10mM or acidic pH (pH 6.0, i.e. additive. These data suggest that combining fatigue metabolites in muscle produces a synergistic effect on muscle nociception.

  8. Emergence of flagellar beating from the collective behavior of individual ATP-powered dyneins


    Namdeo, S.; Onck, P. R.


    Flagella are hair-like projections from the surface of eukaryotic cells, and they play an important role in many cellular functions, such as cell-motility. The beating of flagella is enabled by their internal architecture, the axoneme, and is powered by a dense distribution of motor proteins, dyneins. The dyneins deliver the required mechanical work through the hydrolysis of ATP. Although the dynein-ATP cycle, the axoneme microstructure, and the flagellar-beating kinematics are well studied, ...

  9. Changes in dermal interstitial ATP levels during local heating of human skin. (United States)

    Gifford, Jayson R; Heal, Cory; Bridges, Jarom; Goldthorpe, Scott; Mack, Gary W


    Heating skin is believed to activate vanilloid type III and IV transient receptor potential ion channels (TRPV3, TRPV4, respectively), resulting in the release of ATP into the interstitial fluid. We examined the hypothesis that local skin heating would result in an accumulation of ATP in the interstitial fluid that would be related with a rise in skin blood flow (SkBF) and temperature sensation. Two microdialysis probes were inserted into the dermis on the dorsal aspect of the forearm in 15 young, healthy subjects. The probed skin was maintained at 31°C, 35°C, 39°C and 43°C for 8 min periods, during which SkBF was monitored as cutaneous vascular conductance (CVC). Dialysate was collected and analysed for ATP ([ATP](d)) using a luciferase-based assay, and ratings of perceived warmth were taken at each temperature. At a skin temperature of 31°C, [ATP](d) averaged 18.93 ± 4.06 nm and CVC averaged 12.57 ± 1.59% peak. Heating skin to 35°C resulted in an increase in CVC (17.63 ± 1.27% peak; P ATP](d). Heating skin to 39°C and 43°C resulted in a decreased [ATP](d) (5.88 ± 1.68 nm and 8.75 ± 3.44 nm, respectively; P ATP does not occur during local heating, and therefore does not have a role in temperature sensation or the dilator response in human skin. Nevertheless, the low threshold of dilatation (35°C) indicates a possible role for the TRPV3, TRPV4 channels or the sensitization of other ion channels in mediating the dilator response.

  10. Interaction of ATP with acid-denatured cytochrome c via coupled folding-binding mechanism

    International Nuclear Information System (INIS)

    Ahluwalia, Unnati; Deep, Shashank


    Highlights: ► Interaction between ATP and cyt c takes place via coupled binding–folding mechanism. ► Binding of ATP to cyt c is endothermic. ► GTP and CTP induce similar level of helicity in acid-denatured cyt c as with ATP. ► Compactness induced by ATP is far greater than ADP or AMP. - Abstract: The non-native conformations of the cytochrome c (cyt c) are believed to play key roles in a number of physiological processes. Nucleotides are supposed to act as allosteric effectors in these processes by regulating structural transitions among different conformations of cyt c. To understand the interaction between acid denatured cytochrome c and nucleotides, spectroscopic and calorimetric techniques were utilized to observe the structural features of the induced conformation and the energetics of interaction of acid denatured cyt c with different nucleotides. Structure induction in the acid denatured cyt c was observed on the addition of the ∼1 mM nucleotide tri-phosphates (ATP/GTP/CTP) at 25 °C, however, not in the presence of 1 mM nucleotide mono and diphosphates. ATP-bound cyt c at pH 2.0 is likely to have a conformation that has intact α-helical domain. However, Met80-Fe(III) axial bond is still ruptured. Observed thermodynamics reflect interaction between nucleotide and cyt c via coupled binding–folding mechanism. DSC data suggest the preferential binding of the ATP to the folded conformation with respect to the acid denatured cyt c. ITC data indicate that the exothermic folding of cyt c was accompanied by endothermic binding of ATP to cyt c.

  11. Contribution à la formulation et à l'évaluation de liposomes d'ATP


    Vincourt-Vitse, Véronique,


    ATP liposome incorporating hepatic ligands may contribute to improve the energetic status of the liver graft. In a first phase of development, it has been emphasized the great need of stabilizing the liposome (i) and of validating a cellular model with an altered energetic status in order to test the formulations of interest. To provide a stable liposomal preparation, different strategies have been carried out to freeze-dry liposome with or without ATP. Sucrose and trehalose better stabilize ...

  12. The therapeutic promise of ATP antagonism at P2X3 receptors in respiratory & urological disorders

    Directory of Open Access Journals (Sweden)

    Anthony eFord


    Full Text Available A sensory role for ATP was proposed long before general acceptance of its extracellular role. ATP activates & sensitizes signal transmission at multiple sites along the sensory axis, across multiple synapses. P2X & P2Y receptors mediate ATP modulation of sensory pathways & participate in dysregulation, where ATP action directly on primary afferent neurons (PANs, linking receptive field to CNS, has received much attention. Many PANs, especially C-fibers, are activated by ATP, via P2X3-containing trimers. P2X3 knock-out mice & knock-down in rats led to reduced nocifensive activity & visceral reflexes, suggesting that antagonism may offer benefit in sensory disorders. Recently, drug-like P2X3 antagonists, active in a many inflammatory & visceral pain models, have emerged. Significantly, these compounds have no overt CNS action & are inactive versus acute nociception. Selectively targeting ATP sensitization of PANs may lead to therapies that block inappropriate chronic signals at their source, decreasing drivers of peripheral & central wind-up, yet leaving defensive nociceptive and brain functions unperturbed. This article reviews this evidence, focusing on how ATP sensitization of PANs in visceral hollow organs primes them to chronic discomfort, irritation & pain (symptoms as well as exacerbated autonomic reflexes (signs, & how the use of isolated organ-nerve preparations has revealed this mechanism. Urinary & airways systems share many features: dependence on continuous afferent traffic to brainstem centers to coordinate efferent autonomic outflow; loss of descending inhibitory influence in functional & sensory disorders; dependence on ATP in mediating sensory responses to diverse mechanical and chemical stimuli; a mechanistically overlapping array of existing medicines for pathological conditions. These similarities may also play out in terms of future treatment of signs & symptoms, in the potential for benefit of P2X3 antagonists.

  13. Assessment of in vitro radiosensitivity of human peripheral blood lymphocytes

    International Nuclear Information System (INIS)

    Knox, S.J.; Shifrine, M.; Rosenblatt, L.S.


    The proliferative capacity of sensitive lymphocyte progenitor cells, from thirty-one clinically normal adults, was evaluated following in vitro x-irradiation (0-400R). Radiation effects were studied using both whole blood and lymphocyte-enriched mononuclear cell fractions in the lymphocyte stimulation test and colony formation assay with 6 different mitogens and antigens. Radiation dose-response survival curves were determined for the different test groups. The sensitivity of the different assay systems is compared and normative values are presented that may be used for comparison purposes to determine the relative radiosensitivity of atypical individuals and groups of individuals

  14. Lymphocyte mediators of delayed hypersensitivity; the early phase cells

    Energy Technology Data Exchange (ETDEWEB)

    Lefford, M J; McGregor, D D [Trudeau Inst., Saranac Lake, N.Y. (USA)


    Inbred rats were immunized with living Bacillus Calmette-Guerin (BCG) and lymphocytes which mediate tuberculin DTH and anti-tuberculosis immunity were found 10 days later in the draining lymph nodes, thoracic duct, blood, spleen, and acute peritoneal exudates. The lymphocytes that mediated DTH incorporated /sup 3/HT in vitro, were large in size, sensitive to vinblastine but relatively resistant to irradiation, and had a short effective lifespan in syngeneic recipients. These properties characterize the cells as short-lived, nonrecirculating immunoblasts. In some experimental situations it was possible to dissociate the expression of DTH and immunity following the transfer of sensitized lymphocytes.

  15. Functional mitochondrial ATP synthase proteolipid gene produced by recombination of parental genes in a petunia somatic hybrid

    International Nuclear Information System (INIS)

    Rothenberg, M.; Hanson, M.R.


    A novel ATP synthase subunit 9 gene (atp9) was identified in the mitochondrial genome of a Petunia somatic hybrid line (13-133) which was produced from a fusion between Petunia lines 3688 and 3704. The novel gene was generated by intergenomic recombination between atp9 genes from the two parental plant lines. The entire atp9 coding region is represented on the recombinant gene. Comparison of gene sequences using electrophoresis and autoradiography, indicate that the 5' transcribed region is contributed by an atp9 gene from 3704 and the 3' transcribed region is contributed by an atp9 gene from 3688. The recombinant atp9 gene is transcriptionally active. The location of the 5' and 3' transcript termini are conserved with respect to the parental genes, resulting in the production of hybrid transcripts

  16. De novo mutations in ATP1A3 cause alternating hemiplegia of childhood (United States)

    Heinzen, Erin L.; Swoboda, Kathryn J.; Hitomi, Yuki; Gurrieri, Fiorella; Nicole, Sophie; de Vries, Boukje; Tiziano, F. Danilo; Fontaine, Bertrand; Walley, Nicole M.; Heavin, Sinéad; Panagiotakaki, Eleni; Fiori, Stefania; Abiusi, Emanuela; Di Pietro, Lorena; Sweney, Matthew T.; Newcomb, Tara M.; Viollet, Louis; Huff, Chad; Jorde, Lynn B.; Reyna, Sandra P.; Murphy, Kelley J.; Shianna, Kevin V.; Gumbs, Curtis E.; Little, Latasha; Silver, Kenneth; Ptác̆ek, Louis J.; Haan, Joost; Ferrari, Michel D.; Bye, Ann M.; Herkes, Geoffrey K.; Whitelaw, Charlotte M.; Webb, David; Lynch, Bryan J.; Uldall, Peter; King, Mary D.; Scheffer, Ingrid E.; Neri, Giovanni; Arzimanoglou, Alexis; van den Maagdenberg, Arn M.J.M.; Sisodiya, Sanjay M.; Mikati, Mohamad A.; Goldstein, David B.; Nicole, Sophie; Gurrieri, Fiorella; Neri, Giovanni; de Vries, Boukje; Koelewijn, Stephany; Kamphorst, Jessica; Geilenkirchen, Marije; Pelzer, Nadine; Laan, Laura; Haan, Joost; Ferrari, Michel; van den Maagdenberg, Arn; Zucca, Claudio; Bassi, Maria Teresa; Franchini, Filippo; Vavassori, Rosaria; Giannotta, Melania; Gobbi, Giuseppe; Granata, Tiziana; Nardocci, Nardo; De Grandis, Elisa; Veneselli, Edvige; Stagnaro, Michela; Gurrieri, Fiorella; Neri, Giovanni; Vigevano, Federico; Panagiotakaki, Eleni; Oechsler, Claudia; Arzimanoglou, Alexis; Nicole, Sophie; Giannotta, Melania; Gobbi, Giuseppe; Ninan, Miriam; Neville, Brian; Ebinger, Friedrich; Fons, Carmen; Campistol, Jaume; Kemlink, David; Nevsimalova, Sona; Laan, Laura; Peeters-Scholte, Cacha; van den Maagdenberg, Arn; Casaer, Paul; Casari, Giorgio; Sange, Guenter; Spiel, Georg; Boneschi, Filippo Martinelli; Zucca, Claudio; Bassi, Maria Teresa; Schyns, Tsveta; Crawley, Francis; Poncelin, Dominique; Vavassori, Rosaria


    Alternating hemiplegia of childhood (AHC) is a rare, severe neurodevelopmental syndrome characterized by recurrent hemiplegic episodes and distinct neurologic manifestations. AHC is usually a sporadic disorder with unknown etiology. Using exome sequencing of seven patients with AHC, and their unaffected parents, we identified de novo nonsynonymous mutations in ATP1A3 in all seven AHC patients. Subsequent sequence analysis of ATP1A3 in 98 additional patients revealed that 78% of AHC cases have a likely causal ATP1A3 mutation, including one inherited mutation in a familial case of AHC. Remarkably, six ATP1A3 mutations explain the majority of patients, including one observed in 36 patients. Unlike ATP1A3 mutations that cause rapid-onset-dystonia-parkinsonism, AHC-causing mutations revealed consistent reductions in ATPase activity without effects on protein expression. This work identifies de novo ATP1A3 mutations as the primary cause of AHC, and offers insight into disease pathophysiology by expanding the spectrum of phenotypes associated with mutations in this gene. PMID:22842232

  17. Opposite effect of ATP on contraction force of tonic and phasic skeletal muscles in frogs. (United States)

    Grishin, S N; Kamaliev, R R; Teplov, A Yu; Ziganshin, A U


    Experiments in vitro showed that ATP and adenosine equally suppressed contractions of frog m. sartorius, which belongs to the phasic type muscles. Adenosine receptors antagonist 8-SPT abolished the effect of adenosine, but did not change the effect of ATP. This fact proves the independence of signaling pathways of these purines. ATP produced an opposite effect on the tonic muscle m. cruralis and increased the force of its contraction. Adenosine produced an inhibitory effect on the force of m. cruralis contration. In this case, 8-SPT also eliminated the effect of adenosine, but did not change the effect of ATP. The potentiating effect of ATP was blocked by suramin, a nonselective antagonist of P2 receptors, which attests to their involvement into the effects of this purine. The opposite effects of purinergic regulation reflect fundamental differences in functional organization of phasic and tonic muscular systems. It was hypothesized that the increase in contraction force under the effect of ATP is a mechanism providing maitenance of the contracted state of tonic muscle without appreciable metabolic costs.

  18. Use of luciferase probes to measure ATP in living cells and animals. (United States)

    Morciano, Giampaolo; Sarti, Alba Clara; Marchi, Saverio; Missiroli, Sonia; Falzoni, Simonetta; Raffaghello, Lizzia; Pistoia, Vito; Giorgi, Carlotta; Di Virgilio, Francesco; Pinton, Paolo


    ATP, the energy exchange factor that connects anabolism and catabolism, is required for major reactions and processes that occur in living cells, such as muscle contraction, phosphorylation and active transport. ATP is also the key molecule in extracellular purinergic signaling mechanisms, with an established crucial role in inflammation and several additional disease conditions. Here, we describe detailed protocols to measure the ATP concentration in isolated living cells and animals using luminescence techniques based on targeted luciferase probes. In the presence of magnesium, oxygen and ATP, the protein luciferase catalyzes oxidation of the substrate luciferin, which is associated with light emission. Recombinantly expressed wild-type luciferase is exclusively cytosolic; however, adding specific targeting sequences can modify its cellular localization. Using this strategy, we have constructed luciferase chimeras targeted to the mitochondrial matrix and the outer surface of the plasma membrane. Here, we describe optimized protocols for monitoring ATP concentrations in the cytosol, mitochondrial matrix and pericellular space in living cells via an overall procedure that requires an average of 3 d. In addition, we present a detailed protocol for the in vivo detection of extracellular ATP in mice using luciferase-transfected reporter cells. This latter procedure may require up to 25 d to complete.

  19. ATP-Binding Cassette Proteins: Towards a Computational View of Mechanism (United States)

    Liao, Jielou


    Many large machine proteins can generate mechanical force and undergo large-scale conformational changes (LSCC) to perform varying biological tasks in living cells by utilizing ATP. Important examples include ATP-binding cassette (ABC) transporters. They are membrane proteins that couple ATP binding and hydrolysis to the translocation of substrates across membranes [1]. To interpret how the mechanical force generated by ATP binding and hydrolysis is propagated, a coarse-grained ATP-dependent harmonic network model (HNM) [2,3] is applied to the ABC protein, BtuCD. This protein machine transports vitamin B12 across membranes. The analysis shows that subunits of the protein move against each other in a concerted manner. The lowest-frequency modes of the BtuCD protein are found to link the functionally critical domains, and are suggested to be responsible for large-scale ATP-coupled conformational changes. [1] K. P. Locher, A. T. Lee and D. C. Rees. Science 296, 1091-1098 (2002). [2] Atilgan, A. R., S. R. Durell, R. L. Jernigan, M. C. Demirel, O. Keskin, and I. Bahar. Biophys. J. 80, 505-515(2002); M. M Tirion, Phys. Rev. Lett. 77, 1905-1908 (1996). [3] J. -L. Liao and D. N. Beratan, 2003, to be published.

  20. Colorimetric method for enzymatic screening assay of ATP using Fe(III)-xylenol orange complex formation. (United States)

    Ishida, Akihiko; Yamada, Yasuko; Kamidate, Tamio


    In hygiene management, recently there has been a significant need for screening methods for microbial contamination by visual observation or with commonly used colorimetric apparatus. The amount of adenosine triphosphate (ATP) can serve as the index of a microorganism. This paper describes the development of a colorimetric method for the assay of ATP, using enzymatic cycling and Fe(III)-xylenol orange (XO) complex formation. The color characteristics of the Fe(III)-XO complexes, which show a distinct color change from yellow to purple, assist the visual observation in screening work. In this method, a trace amount of ATP was converted to pyruvate, which was further amplified exponentially with coupled enzymatic reactions. Eventually, pyruvate was converted to the Fe(III)-XO complexes through pyruvate oxidase reaction and Fe(II) oxidation. As the assay result, yellow or purple color was observed: A yellow color indicates that the ATP concentration is lower than the criterion of the test, and a purple color indicates that the ATP concentration is higher than the criterion. The method was applied to the assay of ATP extracted from Escherichia coli cells added to cow milk.

  1. Origin Licensing Requires ATP Binding and Hydrolysis by the MCM Replicative Helicase (United States)

    Coster, Gideon; Frigola, Jordi; Beuron, Fabienne; Morris, Edward P.; Diffley, John F.X.


    Summary Loading of the six related Minichromosome Maintenance (MCM) proteins as head-to-head double hexamers during DNA replication origin licensing is crucial for ensuring once-per-cell-cycle DNA replication in eukaryotic cells. Assembly of these prereplicative complexes (pre-RCs) requires the Origin Recognition Complex (ORC), Cdc6, and Cdt1. ORC, Cdc6, and MCM are members of the AAA+ family of ATPases, and pre-RC assembly requires ATP hydrolysis. Here we show that ORC and Cdc6 mutants defective in ATP hydrolysis are competent for origin licensing. However, ATP hydrolysis by Cdc6 is required to release nonproductive licensing intermediates. We show that ATP binding stabilizes the wild-type MCM hexamer. Moreover, by analyzing MCM containing mutant subunits, we show that ATP binding and hydrolysis by MCM are required for Cdt1 release and double hexamer formation. This work alters our view of how ATP is used by licensing factors to assemble pre-RCs. PMID:25087873

  2. Development of an ATP assay for rapid onboard testing to detect living microorganisms in ballast water (United States)

    Hyun, Bonggil; Cha, Hyung-Gon; Lee, Nayoung; Yum, Seungshic; Baek, Seung Ho; Shin, Kyoungsoon


    Ballast water is a principal pathway for the introduction of pathogens and non-indigenous species to ports worldwide. The International Maritime Organization (IMO) and the United States Coast Guard (USCG) have adopted ballast water management regulations that require, e.g., the installation of shipboard ballast water management systems (BWMS). Rapid and simple analytical methods are needed to monitor whether ballast water disinfection ensures compliance with the discharge standards. In this study laboratory and full scale land-based testing was used to investigate the suitability of an adenosine triphosphate (ATP) assay for quantifying living organisms (≥ 10 and land-based testing the ATP assay also showed a good correlation with the presence of living natural plankton cells in control samples, but the ATP concentration (137 pg mL- 1) was much lower than the ATP guideline. The low ATP concentration in natural plankton cells may reflect a decline in their biological activity because of extended exposure to dark conditions. Although our results need further validation, the ATP assay is a suitable tool for monitoring compliance of ballast water treatment.

  3. Rapid granulation tissue regeneration by intracellular ATP delivery--a comparison with Regranex.

    Directory of Open Access Journals (Sweden)

    Jeffrey D Howard

    Full Text Available This study tests a new intracellular ATP delivery technique for tissue regeneration and compares its efficacy with that of Regranex. Twenty-seven adult New Zealand white rabbits each underwent minimally invasive surgery to render one ear ischemic. Eight wounds were then created: four on the ischemic and four on the normal ear. Two wounds on one side of each ear were treated with Mg-ATP encapsulated lipid vesicles (ATP-vesicles while the two wounds on the other side were treated with Regranex. Wound healing time was shorter when ATP-vesicles were used. The most striking finding was that new tissue growth started to appear in less than 1 day when ATP-vesicles were used. The growth continued and covered the wound area within a few days, without the formation of a provisional matrix. Regranex-treated wounds did not have this growth pattern. In wounds treated by ATP-vesicles, histologic studies revealed extremely rich macrophage accumulation, along with active proliferating cell nuclear antigen (PCNA and positive BrdU staining, indicating in situ macrophage proliferation. Human macrophage culture suggested direct collagen production. These results support an entirely new healing process, which seems to have combined the conventional hemostasis, inflammation, and proliferation phases into a single one, thereby eliminating the lag time usually seen during healing process.

  4. Silencing of Atp2b1 increases blood pressure through vasoconstriction. (United States)

    Shin, Young-Bin; Lim, Ji Eun; Ji, Su-Min; Lee, Hyeon-Ju; Park, So-Yon; Hong, Kyung-Won; Lim, Mihwa; McCarthy, Mark I; Lee, Young-Ho; Oh, Bermseok


    Recent genome-wide association studies (GWASs) have identified 30 genetic loci that regulate blood pressure, increasing our understanding of the cause of hypertension. However, it has been difficult to define the causative genes at these loci due to a lack of functional analyses. In this study, we aimed to validate the candidate gene ATP2B1 in 12q21, variants near which have the strongest association with blood pressure in Asians and Europeans. ATP2B1 functions as a calcium pump to fine-tune calcium concentrations - necessary for repolarization following muscular contractions. We silenced Atp2b1 using an siRNA complex, injected into mouse tail veins. In treated mice, blood pressure rose and the mesenteric arteries increased in wall : lumen ratio. Moreover, the arteries showed enhanced myogenic responses to pressure, and contractile responses to phenylephrine increased compared with the control, suggesting that blood pressure is regulated by ATP2B1 through the contraction and dilation of the vessel, likely by controlling calcium concentrations in the resting state. These results support that ATP2B1 is the causative gene in the blood pressure-associated 12q21 locus and demonstrate that ATP2B1 expression in the vessel influences blood pressure.

  5. ATP as a Multi-target Danger Signal in the Brain

    Directory of Open Access Journals (Sweden)

    Ricardo J Rodrigues


    Full Text Available ATP is released in an activity-dependent manner from different cell types in the brain, fulfilling different roles as a neurotransmitter, neuromodulator, astrocyte-to-neuron communication, propagating astrocytic responses and formatting microglia responses. This involves the activation of different ATP P2 receptors (P2R as well as adenosine receptors upon extracellular ATP catabolism by ecto-nucleotidases. Notably, brain noxious stimuli trigger a sustained increase of extracellular ATP, which plays a key role as danger signal in the brain. This involves a combined action of extracellular ATP in different cell types, namely increasing the susceptibility of neurons to damage, promoting astrogliosis and recruiting and formatting microglia to mount neuroinflammatory responses. Such actions involve the activation of different receptors, as heralded by neuroprotective effects resulting from blockade mainly of P2X7R, P2Y1R and adenosine A2A receptors (A2AR, which hierarchy, cooperation and/or redundancy is still not resolved. These pleiotropic functions of ATP as a danger signal in brain damage prompt a therapeutic interest to multi-target different purinergic receptors to provide maximal opportunities for neuroprotection.

  6. Dynamic inhibition of excitatory synaptic transmission by astrocyte-derived ATP in hippocampal cultures (United States)

    Koizumi, Schuichi; Fujishita, Kayoko; Tsuda, Makoto; Shigemoto-Mogami, Yukari; Inoue, Kazuhide


    Originally ascribed passive roles in the CNS, astrocytes are now known to have an active role in the regulation of synaptic transmission. Neuronal activity can evoke Ca2+ transients in astrocytes, and Ca2+ transients in astrocytes can evoke changes in neuronal activity. The excitatory neurotransmitter glutamate has been shown to mediate such bidirectional communication between astrocytes and neurons. We demonstrate here that ATP, a primary mediator of intercellular Ca2+ signaling among astrocytes, also mediates intercellular signaling between astrocytes and neurons in hippocampal cultures. Mechanical stimulation of astrocytes evoked Ca2+ waves mediated by the release of ATP and the activation of P2 receptors. Mechanically evoked Ca2+ waves led to decreased excitatory glutamatergic synaptic transmission in an ATP-dependent manner. Exogenous application of ATP does not affect postsynaptic glutamatergic responses but decreased presynaptic exocytotic events. Finally, we show that astrocytes exhibit spontaneous Ca2+ waves mediated by extracellular ATP and that inhibition of these Ca2+ responses enhanced excitatory glutamatergic transmission. We therefore conclude that ATP released from astrocytes exerts tonic and activity-dependent down-regulation of synaptic transmission via presynaptic mechanisms.

  7. Escherichia coli contains a soluble ATP-dependent protease (Ti) distinct from protease La

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, B.J.; Park, W.J.; Chung, C.H.; Goldberg, A.L.


    The energy requirement for protein breakdown in Escherichia coli has generally been attributed to the ATP-dependence of protease La, the lon gene product. The authors have partially purified another ATP-dependent protease from lon/sup -/ cells that lack protease La (as shown by immunoblotting). This enzyme hydrolyzes (/sup 3/H)methyl-casein to acid-soluble products in the presence of ATP and Mg/sup 2 +/. ATP hydrolysis appears necessary for proteolytic activity. Since this enzyme is inhibited by diisopropyl fluorophosphate, it appears to be a serine protease, but it also contains essential thiol residues. They propose to name this enzyme protease Ti. It differs from protease La in nucleotide specificity, inhibitor sensitivity, and subunit composition. On gel filtration, protease Ti has an apparent molecular weight of 370,000. It can be fractionated by phosphocellulose chromatography or by DEAE chromatography into two components with apparent molecular weights of 260,000 and 140,000. When separated, they do not show preteolytic activity. One of these components, by itself, has ATPase activity and is labile in the absence of ATP. The other contains the diisopropyl fluorophosphate-sensitive proteolytic site. These results and the similar findings of Katayama-Fujimura et al. indicate that E. coli contains two ATP-hydrolyzing proteases, which differ in many biochemical features and probably in their physiological roles.

  8. Escherichia coli contains a soluble ATP-dependent protease (Ti) distinct from protease La

    International Nuclear Information System (INIS)

    Hwang, B.J.; Park, W.J.; Chung, C.H.; Goldberg, A.L.


    The energy requirement for protein breakdown in Escherichia coli has generally been attributed to the ATP-dependence of protease La, the lon gene product. The authors have partially purified another ATP-dependent protease from lon - cells that lack protease La (as shown by immunoblotting). This enzyme hydrolyzes [ 3 H]methyl-casein to acid-soluble products in the presence of ATP and Mg 2+ . ATP hydrolysis appears necessary for proteolytic activity. Since this enzyme is inhibited by diisopropyl fluorophosphate, it appears to be a serine protease, but it also contains essential thiol residues. They propose to name this enzyme protease Ti. It differs from protease La in nucleotide specificity, inhibitor sensitivity, and subunit composition. On gel filtration, protease Ti has an apparent molecular weight of 370,000. It can be fractionated by phosphocellulose chromatography or by DEAE chromatography into two components with apparent molecular weights of 260,000 and 140,000. When separated, they do not show preteolytic activity. One of these components, by itself, has ATPase activity and is labile in the absence of ATP. The other contains the diisopropyl fluorophosphate-sensitive proteolytic site. These results and the similar findings of Katayama-Fujimura et al. indicate that E. coli contains two ATP-hydrolyzing proteases, which differ in many biochemical features and probably in their physiological roles

  9. Evolutionary relationships of ATP-Binding Cassette (ABC) uptake porters. (United States)

    Zheng, Wei Hao; Västermark, Åke; Shlykov, Maksim A; Reddy, Vamsee; Sun, Eric I; Saier, Milton H


    The ATP-Binding Cassette (ABC) functional superfamily includes integral transmembrane exporters that have evolved three times independently, forming three families termed ABC1, ABC2 and ABC3, upon which monophyletic ATPases have been superimposed for energy-coupling purposes [e.g., J Membr Biol 231(1):1-10, 2009]. The goal of the work reported in this communication was to understand how the integral membrane constituents of ABC uptake transporters with different numbers of predicted or established transmembrane segments (TMSs) evolved. In a few cases, high resolution 3-dimensional structures were available, and in these cases, their structures plus primary sequence analyses allowed us to predict evolutionary pathways of origin. All of the 35 currently recognized families of ABC uptake proteins except for one (family 21) were shown to be homologous using quantitative statistical methods. These methods involved using established programs that compare native protein sequences with each other, after having compared each sequence with thousands of its own shuffled sequences, to gain evidence for homology. Topological analyses suggested that these porters contain numbers of TMSs ranging from four or five to twenty. Intragenic duplication events occurred multiple times during the evolution of these porters. They originated from a simple primordial protein containing 3 TMSs which duplicated to 6 TMSs, and then produced porters of the various topologies via insertions, deletions and further duplications. Except for family 21 which proved to be related to ABC1 exporters, they are all related to members of the previously identified ABC2 exporter family. Duplications that occurred in addition to the primordial 3 → 6 duplication included 5 → 10, 6 → 12 and 10 → 20 TMSs. In one case, protein topologies were uncertain as different programs gave discrepant predictions. It could not be concluded with certainty whether a 4 TMS ancestral protein or a 5 TMS ancestral protein

  10. ATP-binding cassette transporters in reproduction: a new frontier (United States)

    Bloise, E.; Ortiga-Carvalho, T.M.; Reis, F.M.; Lye, S.J.; Gibb, W.; Matthews, S.G.


    BACKGROUND The transmembrane ATP-binding cassette (ABC) transporters actively efflux an array of clinically relevant compounds across biological barriers, and modulate biodistribution of many physiological and pharmacological factors. To date, over 48 ABC transporters have been identified and shown to be directly and indirectly involved in peri-implantation events and fetal/placental development. They efflux cholesterol, steroid hormones, vitamins, cytokines, chemokines, prostaglandins, diverse xenobiotics and environmental toxins, playing a critical role in regulating drug disposition, immunological responses and lipid trafficking, as well as preventing fetal accumulation of drugs and environmental toxins. METHODS This review examines ABC transporters as important mediators of placental barrier functions and key reproductive processes. Expression, localization and function of all identified ABC transporters were systematically reviewed using PubMed and Google Scholar websites to identify relevant studies examining ABC transporters in reproductive tissues in physiological and pathophysiological states. Only reports written in English were incorporated with no restriction on year of publication. While a major focus has been placed on the human, extensive evidence from animal studies is utilized to describe current understanding of the regulation and function of ABC transporters relevant to human reproduction. RESULTS ABC transporters are modulators of steroidogenesis, fertilization, implantation, nutrient transport and immunological responses, and function as ‘gatekeepers’ at various barrier sites (i.e. blood-testes barrier and placenta) against potentially harmful xenobiotic factors, including drugs and environmental toxins. These roles appear to be species dependent and change as a function of gestation and development. The best-described ABC transporters in reproductive tissues (primarily in the placenta) are the multidrug transporters p-glycoprotein and

  11. Atp1a3-deficient heterozygous mice show lower rank in the hierarchy and altered social behavior. (United States)

    Sugimoto, H; Ikeda, K; Kawakami, K


    Atp1a3 is the Na-pump alpha3 subunit gene expressed mainly in neurons of the brain. Atp1a3-deficient heterozygous mice (Atp1a3 +/- ) show altered neurotransmission and deficits of motor function after stress loading. To understand the function of Atp1a3 in a social hierarchy, we evaluated social behaviors (social interaction, aggression, social approach and social dominance) of Atp1a3 +/- and compared the rank and hierarchy structure between Atp1a3 +/- and wild-type mice within a housing cage using the round-robin tube test and barbering observations. Formation of a hierarchy decreases social conflict and promote social stability within the group. The hierarchical rank is a reflection of social dominance within a cage, which is heritable and can be regulated by specific genes in mice. Here we report: (1) The degree of social interaction but not aggression was lower in Atp1a3 +/- than wild-type mice, and Atp1a3 +/- approached Atp1a3 +/- mice more frequently than wild type. (2) The frequency of barbering was lower in the Atp1a3 +/- group than in the wild-type group, while no difference was observed in the mixed-genotype housing condition. (3) Hierarchy formation was not different between Atp1a3 +/- and wild type. (4) Atp1a3 +/- showed a lower rank in the mixed-genotype housing condition than that in the wild type, indicating that Atp1a3 regulates social dominance. In sum, Atp1a3 +/- showed unique social behavior characteristics of lower social interaction and preference to approach the same genotype mice and a lower ranking in the hierarchy. © 2017 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

  12. Interaction of ATP with a small heat shock protein from Mycobacterium leprae: effect on its structure and function. (United States)

    Nandi, Sandip Kumar; Chakraborty, Ayon; Panda, Alok Kumar; Ray, Sougata Sinha; Kar, Rajiv Kumar; Bhunia, Anirban; Biswas, Ashis


    Adenosine-5'-triphosphate (ATP) is an important phosphate metabolite abundantly found in Mycobacterium leprae bacilli. This pathogen does not derive ATP from its host but has its own mechanism for the generation of ATP. Interestingly, this molecule as well as several antigenic proteins act as bio-markers for the detection of leprosy. One such bio-marker is the 18 kDa antigen. This 18 kDa antigen is a small heat shock protein (HSP18) whose molecular chaperone function is believed to help in the growth and survival of the pathogen. But, no evidences of interaction of ATP with HSP18 and its effect on the structure and chaperone function of HSP18 are available in the literature. Here, we report for the first time evidences of "HSP18-ATP" interaction and its consequences on the structure and chaperone function of HSP18. TNP-ATP binding experiment and surface plasmon resonance measurement showed that HSP18 interacts with ATP with a sub-micromolar binding affinity. Comparative sequence alignment between M. leprae HSP18 and αB-crystallin identified the sequence 49KADSLDIDIE58 of HSP18 as the Walker-B ATP binding motif. Molecular docking studies revealed that β4-β8 groove/strands as an ATP interactive region in M. leprae HSP18. ATP perturbs the tertiary structure of HSP18 mildly and makes it less susceptible towards tryptic cleavage. ATP triggers exposure of additional hydrophobic patches at the surface of HSP18 and induces more stability against chemical and thermal denaturation. In vitro aggregation and thermal inactivation assays clearly revealed that ATP enhances the chaperone function of HSP18. Our studies also revealed that the alteration in the chaperone function of HSP18 is reversible and is independent of ATP hydrolysis. As the availability and binding of ATP to HSP18 regulates its chaperone function, this functional inflection may play an important role in the survival of M. leprae in hosts.

  13. Ca2+-regulated-cAMP/PKA signaling in cardiac pacemaker cells links ATP supply to demand. (United States)

    Yaniv, Yael; Juhaszova, Magdalena; Lyashkov, Alexey E; Spurgeon, Harold A; Sollott, Steven J; Lakatta, Edward G


    In sinoatrial node cells (SANC), Ca(2+) activates adenylate cyclase (AC) to generate a high basal level of cAMP-mediated/protein kinase A (PKA)-dependent phosphorylation of Ca(2+) cycling proteins. These result in spontaneous sarcoplasmic-reticulum (SR) generated rhythmic Ca(2+) oscillations during diastolic depolarization, that not only trigger the surface membrane to generate rhythmic action potentials (APs), but, in a feed-forward manner, also activate AC/PKA signaling. ATP is consumed to pump Ca(2+) to the SR, to produce cAMP, to support contraction and to maintain cell ionic homeostasis. Since feedback mechanisms link ATP-demand to ATP production, we hypothesized that (1) both basal ATP supply and demand in SANC would be Ca(2+)-cAMP/PKA dependent; and (2) due to its feed-forward nature, a decrease in flux through the Ca(2+)-cAMP/PKA signaling axis will reduce the basal ATP production rate. O(2) consumption in spontaneous beating SANC was comparable to ventricular myocytes (VM) stimulated at 3 Hz. Graded reduction of basal Ca(2+)-cAMP/PKA signaling to reduce ATP demand in rabbit SANC produced graded ATP depletion (r(2)=0.96), and reduced O(2) consumption and flavoprotein fluorescence. Neither inhibition of glycolysis, selectively blocking contraction nor specific inhibition of mitochondrial Ca(2+) flux reduced the ATP level. Feed-forward basal Ca(2+)-cAMP/PKA signaling both consumes ATP to drive spontaneous APs in SANC and is tightly linked to mitochondrial ATP production. Interfering with Ca(2+)-cAMP/PKA signaling not only slows the firing rate and reduces ATP consumption, but also appears to reduce ATP production so that ATP levels fall. This distinctly differs from VM, which lack this feed-forward basal cAMP/PKA signaling, and in which ATP level remains constant when the demand changes. Published by Elsevier Ltd.

  14. Somatic mutations in ATP1A1 and ATP2B3 lead to aldosterone-producing adenomas and secondary hypertension

    DEFF Research Database (Denmark)

    Beuschlein, Felix; Boulkroun, Sheerazed; Osswald, Andrea


    Primary aldosteronism is the most prevalent form of secondary hypertension. To explore molecular mechanisms of autonomous aldosterone secretion, we performed exome sequencing of aldosterone-producing adenomas (APAs). We identified somatic hotspot mutations in the ATP1A1 (encoding an Na+/K+ ATPase α...

  15. AID protein expression in chronic lymphocytic leukemia/small lymphocytic lymphoma is associated with poor prognosis and complex genetic alterations. (United States)

    Leuenberger, Mona; Frigerio, Simona; Wild, Peter J; Noetzli, Franziska; Korol, Dimitri; Zimmermann, Dieter R; Gengler, Carole; Probst-Hensch, Nicole M; Moch, Holger; Tinguely, Marianne


    The biological behavior of chronic lymphocytic leukemia and small lymphocytic lymphoma is unpredictable. Nonetheless, non-mutated IgV(H) gene rearrangement, ATM (11q22-23) and p53 (17p13) deletion are recognized as unfavorable prognosticators in chronic lymphocytic leukemia. The mRNA expression of activation-induced cytidine deaminase (AID), an enzyme indispensable for somatic hypermutation processes, was claimed to be predictive of non-mutated chronic lymphocytic leukemia cells in blood. Here, we evaluated AID protein expression compared with known molecular and immunohistochemical prognostic indicators in 71 chronic lymphocytic leukemia/small lymphocytic lymphoma patients using a tissue microarray approach. We found AID heterogeneously expressed in tumor cells as shown by colocalization analysis for CD5 and CD23. Ki-67 positive paraimmunoblasts of the proliferation centers displayed the highest expression. This observation is reflected by a significant association of AID positivity with a high proliferation rate (P=0.012). ATM deletion was detected in 10% (6/63) of patients and p53 deletion in 19% (13/67) of patients. Moreover, both ATM (P=0.002) and p53 deletion (P=0.004) were significantly associated with AID. IgV(H) gene mutation was seen in 45% (27/60) of patients. Twenty-five percent (17/69) of patients with AID-positive chronic lymphocytic leukemia/small lymphocytic lymphoma displayed a shorter survival than AID-negative chronic lymphocytic leukemia/small lymphocytic lymphoma patients (61 vs 130 months, P=0.001). Although there was a trend, we could not show an association with the IgV(H) gene mutation status. Taken together, our study shows that AID expression is an indicator of an unfavorable prognosis in chronic lymphocytic leukemia/small lymphocytic lymphoma patients, although it is not a surrogate marker for the IgV(H) status. Furthermore, the microenvironment of proliferation centers seems to influence AID regulation and might be an initiating factor

  16. Increased radiosensitivity of a subpopulation of T-lymphocyte progenitors from patients with Fanconi's anemia

    International Nuclear Information System (INIS)

    Knox, S.; Wilson, F.D.; Greenberg, B.R.; Shifrime, M.; Rosenblatt, L.S.; Reeves, J.D.; Misra, H.P.


    In vitro radiation-survival of peripheral blood T-lymphocytes was studied in fifteen clinically normal adults and four patients with Fanconi's anemia (FA). Lymphocyte blastogenesis and cloning were measured following phytohemagglutinin (PHA) or Concanavalin-A (Con-A) stimulation. PHA-responsive lymphocytes from FA patients were significantly more radiosensitive than lymphocytes from normal individuals

  17. Separation and properties of EA-rosette-forming lymphocytes in humans

    NARCIS (Netherlands)

    van Oers, M. H.; Zeijlemaker, W. P.; Schellekens, P. T.


    Human peripheral blood lymphocytes were separated into subpopulations enriched or depleted with respect to B lymphocytes (Ig-bearing cells), T lymphocytes, (cell forming rosettes with sheep erythrocytes: E-RFC) and Fc receptor-bearing lymphocytes (EA-RFC). From the distributions and recoveries of

  18. The Genotoxicity of Sodium Arsenite in Human Lymphocyte Culture

    International Nuclear Information System (INIS)

    El-Habit Ola, H.M.


    Sodium arsenite was tested for its clastogenic effect alone and on isolated lymphocyte culture. The results showed a significant difference in the yield of chromosome aberrations induced with respect to the culture time 48 h. Whole blood culture showed significant increase in gaps and breaks whereas isolated lymphocyte culture showed significant inhibition of cell cycle and 75% of the lymphocytes were in their first cell cycle at 72 hr. Arsenite showed co-mutagenicity with different doses of x-ray delivered immediately or few hours after treatment of the culture with S A. The results suggest that S A is also mutagenic at the dose level used and provide support for the indispensability of whole blood culture for evaluation of the in vivo effect of any suspected mustagen using isolated lymphocytes appear to have problems leading to extensive cell cycle delay

  19. Chronic Lymphocytic Leukemia Treatment (PDQ®)—Health Professional Version (United States)

    Chronic lymphocytic leukemia (CLL) treatment options can include observation, steroids, chemotherapy, targeted therapy, and/or stem cell transplant. Get detailed information about newly diagnosed and recurrent CLL and available treatment modalities in this summary for clinicians.

  20. The genotoxicity of sodium arsenite in human lymphocyte culture

    International Nuclear Information System (INIS)

    Elhabit, O.H.M.


    Sodium arsenite was tested for its clastogenic effect alone and in combination with x-irradiation on whole blood culture and on isolated lymphocyte culture. The results showed a significant difference in the yield of aberrations induced with respect to the culture time 48 hr whole blood culture showed significant increase in gaps and breaks whereas isolated lymphocytes culture showed significant inhibition of cell cycle and 75% of the lymphocytes were in first cell cycle at 72 hr. Arsenite showed co-mutagenicity with different doses of x-ray delivered immediately or few hours after treatment of the culture with SA. The results suggest that SA also is mutagenic at the dose level used and provide support for the indispensability of whole blood culture for evaluation of the in vivo effect any suspected mutagen. Using isolated lymphocytes appear to have problems leading to extensive cell cycle delay

  1. Response of human lymphocytes to low gamma ray doses

    International Nuclear Information System (INIS)

    Vega Carrillo, HR; Banuelos Valenzuela, R; Manzanares Acuna, E; Sanchez-Rodriguez, S.H


    Radiation and non-radiation workers lymphocytes were exposed to a low strength gamma-ray field to determine heat shock protein expression in function of radiation dose. Protein identification was carried out using mAb raised against Hsp25, Hsp60, Hsp70 and Hsp90; from these, only Hsp70 protein was detected before and after lymphocyte irradiation. In all cases, an increasing trend of relative amounts of Hsp70 in function to irradiation time was observed. After 70.5 mGy gamma-ray dose, radiation worker's lymphocytes expressed more Hsp70 protein, than non-radiation workers' lymphocytes, indicating a larger tolerance to gamma rays (gamma tolerance), due to an adaptation process developed by their labor condition (Au)

  2. Langerhans cells and subsets of lymphocytes in the nasal mucosa

    DEFF Research Database (Denmark)

    Hellquist-Dahl, B; Olsen, K E; Irander, K


    Langerhans cells and different lymphocytes were studied in the nasal mucosa of 39 woodwork teachers and a control group of 14 healthy subjects. Ten of the woodwork teachers were sensitized as determined by skin prick test. A panel of different monoclonal antibodies was applied on the frozen nasal...... mucosal specimens. Intraepithelial CD1-positive dendritic cells were found in all specimens. However, there was no difference between the number of these Langerhans cells found in the study group and the number found in the controls. In every specimen the intraepithelial lymphocyte population...... was dominated by T lymphocytes, and there were relatively few B cells. Similarly the ratio between CD4- and CD8-positive lymphocytes in the study group and the controls was the same. In all specimens there was a dominance of T suppressor/cytotoxic cells compared with T helper/inducer cells. The study confirms...

  3. Neutrophil/lymphocyte ratio and platelet/lymphocyte ratio in mood disorders: A meta-analysis. (United States)

    Mazza, Mario Gennaro; Lucchi, Sara; Tringali, Agnese Grazia Maria; Rossetti, Aurora; Botti, Eugenia Rossana; Clerici, Massimo


    The immune and inflammatory system is involved in the etiology of mood disorders. Neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR) and monocyte/lymphocyte ratio (MLR) are inexpensive and reproducible biomarkers of inflammation. This is the first meta-analysis exploring the role of NLR and PLR in mood disorder. We identified 11 studies according to our inclusion criteria from the main Electronic Databases. Meta-analyses were carried out generating pooled standardized mean differences (SMDs) between index and healthy controls (HC). Heterogeneity was estimated. Relevant sensitivity and meta-regression analyses were conducted. Subjects with bipolar disorder (BD) had higher NLR and PLR as compared with HC (respectively SMD = 0.672; p analysis evidenced an influence of bipolar phase on the overall estimate whit studies including subjects in manic and any bipolar phase showing a significantly higher NLR and PLR as compared with HC whereas the effect was not significant among studies including only euthymic bipolar subjects. Meta-regression showed that age and sex influenced the relationship between BD and NLR but not the relationship between BD and PLR. Meta-analysis was not carried out for MLR because our search identified only one study when comparing BD to HC, and only one study when comparing MDD to HC. Subjects with major depressive disorder (MDD) had higher NLR as compared with HC (SMD = 0.670; p = 0.028; I 2  = 89.931%). Heterogeneity-based sensitivity analyses and meta-regression confirmed these findings. Our meta-analysis supports the hypothesis that an inflammatory activation occurs in mood disorders and NLR and PLR may be useful to detect this activation. More researches including comparison of NLR, PLR and MLR between different bipolar phases and between BD and MDD are needed. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. Biological dosimetry: the potential use of radiation-induced apoptosis in human T-lymphocytes

    International Nuclear Information System (INIS)

    Menz, R.; Andres, R.; Larsson, B.; Ozsahin, M.; Crompton, N.E.A.; Trott, K.


    An assay for biological dosimetry based on the induction of apoptosis in human T-lymphocytes is described. Radiation-induced apoptosis was assessed by flow cytometric identification of cells displaying apoptosis-associated DNA condensation. CD4 and CD8 T-lymphocytes were analysed. They were recognized on the basis of their cell-surface antigens. Four parameters were measured for both cell types: cell size, granularity, antigen immunofluorescence and DNA content. Apoptosis was quantified as the fraction of CD4-, or CD8-positive cells with a characteristic reduction of cell size and DNA content. At doses below 1 Gy, levels of radiation-induced apoptosis increased for up to 5 days after irradiation. Optimal dose discrimination was observed 4 days after irradiation, at which time the dose-response curves were linear, with a slope of 8% ± 0.5% per 0.1 Gy. In controlled, dose-response experiments the lowest dose level at which the radiation-induced apoptosis frequency was still significantly above control was 0.05 Gy. After 5 days post-irradiation incubation, intra- and interdonor variations were measured and found to be similar; thus, apoptotic levels depend more on the dose than on the donor. The results demonstrate the potential of this assay as a biological dosimeter. (orig.)


    Directory of Open Access Journals (Sweden)

    AnnaMaria Nosari


    Full Text Available Infectious complications have been known to be a major cause of morbidity and mortality in CLL patients who are predisposed to infections because of both the humoral immunodepression inherent to hematologic disease, which is related to stage and duration of CLL, and to further immunosuppression related to therapy. The majority of infections in CLL patients treated with alkilating agents is of bacterial origin. The immunodeficiency and natural infectious history of alkylator-resistant, corticosteroid-treated patients appears to have changed with the administration of purine analogs, which has been complicated by very severe and unusual infections and also more viral infections due to sustained reduction of CD4-positive T lymphocytes. The following introduction of monoclonal antibody therapies, in particular alemtuzumab, further increased the immunodepression, increasing also infections which appeared more often in patients with recurrent neutropenia due to chemotherapy cycles. Epidemiological data regarding fungal infections in lymphoproliferative disorders are scarce. Italian SEIFEM group in a retrospective multicentre study regarding CLL patients reported an incidence of mycoses 0.5%; however, chronic lymphoproliferative disorders emerged as second haematological underlying disease after acute leukemia in a French study on aspergillosis; in particular CLL with aspergillosis accounted for a third of these chronic lymphoproliferative diseases presenting mould infection.

  6. Cytogenetic investigations of chronic lymphocytic leukemia. (United States)

    Wren, Catherine; Moriarty, Helen; Marsden, Katherine; Tegg, Elizabeth


    This study aimed to determine which culture method would yield the highest culture success rate, mitotic index, banding resolution, and abnormality rate in investigation of patients with chronic lymphocytic leukemia (CLL). A range of culture techniques for conventional cytogenetic (CC) analyses was compared: 24-hour unstimulated, 72 hours incubation with additional fetal calf serum, 72 hours stimulation with interleukin 4, 72 hours stimulation with lipopolysaccharide (LPS), 72 hours stimulation with TPA (12-O-tetradecanoylphorbol 13-acetate), and 72 hours stimulation with CpG-oligonucleotide DSP30 + Interleukin-2 (IL-2). CC abnormality rates were also compared to fluorescence in situ hybridization (FISH) results using probes for CLL (LSI D13S319/13q34/CEP 12: LSI ATM/p53). Forty-five samples from 24 patients (consisting of 11 newly diagnosed and 13 previously diagnosed patients) were included. For CC, a 100.0% culture success rate was achieved (n = 45) by means of an EDTA (ethylenediaminetetraacetic acid) peripheral blood sample with an associated 62.5% CC abnormality rate (n = 24). FISH detected an abnormality rate of 75.0% (n = 24). The combined CC and FISH abnormality rate was 87.5% (n = 24). This study demonstrates that CC that uses TPA and DSP30 + IL-2 on EDTA peripheral blood is effective in the investigation of CLL and may be used as a supplement to FISH studies. Copyright 2010 Elsevier Inc. All rights reserved.


    Directory of Open Access Journals (Sweden)

    Luca Laurenti


    Full Text Available Even if Chronic lymphocytic leukemia (CLL often has an indolent behavior with good responsiveness to cytoreductive treatment, about 20% of the patients, so called "poor-risk" patients, show an aggressive course and die within a few years despite early intensive therapies. Criteria for poor-risk disease according to the European Bone Marrow Transplantation (EBMT CLL Transplant Consensus are: purine analogue refractoriness, early relapse after purine analogue combination therapy, CLL with p53 lesion requiring treatment. Allogeneic transplant has potential curative role in CLL, however burden with very  high transplant related mortality (TRM rates of 38-50%: A major advance in reducing the short-term morbidity and mortality of allogeneic stem cell transplantation (SCT has been the introduction of non-myeloablative or reduced intensity conditioning (RIC regimens to allow engraftment of allogeneic stem cells. There is no doubt that the crucial therapeutic principle of allo-SCT in CLL is graft versus leukemia (GVL activity. The major complications of allogeneic SCT in CLL are: chronic graft-versus-host-disease (GVHD affecting quality of life, high graft rejection and infection rates rates correlated with preexisting immunosuppression. Disease relapse remains the major cause of failure after RIC allo-HCT in CLL patients. Sensitive minimal residual disease (MRD quantification has strong prognostic impact after transplant.

  8. Therapeutic advancement of chronic lymphocytic leukemia

    Directory of Open Access Journals (Sweden)

    Lu Kang


    Full Text Available Abstract Despite the combinations of chemotherapy with monoclonal antibodies have further improved response rates, chronic lymphocytic leukemia (CLL remains an incurable disease with an extremely variable course. This article reviews the ongoing clinical advances in the treatment of CLL in both previously untreated and relapsed disease and focuses on the benefit of different therapeutic strategies, the most effective therapy combinations and the potential activity of novel agents. Novel agents and combination therapies have been investigated by several studies in both the upfront and relapsed setting, particularly for patients with 17p deletion, TP53 mutation and fludarabine-refractory CLL. While these agents and combination therapies have improved initial response rates, ongoing studies are continued to determine and improve the efficacy and safety. Despite advancements in the treatment of CLL have led to high response rates, allogeneic hematopoietic stem cell transplantation (allo-HSCT remains the only curative option and reduced-intensity conditioning (RIC allo-HSCT must be strongly considered whenever feasible. As such, ongoing studies of these agents and other novel approaches in clinical development are needed to expand and improve treatment options for CLL patients.

  9. Spontaneous unscheduled DNA synthesis in human lymphocytes

    International Nuclear Information System (INIS)

    Forell, B.; Myers, L.S. Jr.; Norman, A.


    The rate of spontaneous unscheduled DNA synthesis in human lymphocytes was estimated from measurements of tritiated thymidine incorporation into double-stranded DNA (ds-DNA) during incubation of cells in vitro. The contribution of scheduled DNA synthesis to the observed incorporation was reduced by inhibiting replication with hydroxyurea and by separating freshly replicated single-stranded DNA (ss-DNA) from repaired ds-DNA by column chromatography. The residual contribution of scheduled DNA synthesis was estimated by observing effects on thymidine incorporation of: (a) increasing the rate of production of apurinic sites, and alternatively, (b) increasing the number of cells in S-phase. Corrections based on estimates of endogenous pool size were also made. The rate of spontaneous unscheduled DNA synthesis is estimated to be 490 +- 120 thymidine molecules incorporated per cell per hour. These results compare favorably with estimates made from rates of depurination and depyrimidination of DNA, measured in molecular systems if we assume thymidine is incorporated by a short patch mechanism which incorporates an average of four bases per lesion

  10. Autoreactive lymphocytes in thyroid disorders. 2

    International Nuclear Information System (INIS)

    Petersen, J.; Feldt-Rasmussen, U.; Siersbaek-Nielsen, K.; Hoeier-Madsen, M.; Larsen, F.; Husby, S.


    Blood mononuclear cells (MNC) from 9 randomly selected patients with autoimmune thyroiditis were stimulated in vitro with pokeweed mitogen (PWM), a polyclonal B lymphocyte activator. The secretion of immunoglobulins (Ig) and anti-thyroglobulin antibodies (TgAb) was assayed by means of haemolytic plaque-forming cell (PFC) assays, radioimmune assay (RIA) and enzyme-linked immunosorbent assays (ELISA). Total Ig and TgAb production was maximal using MNC cultured at 1.0 x 10 6 /ml as estimated by PFC, RIA and ELISA. The Ig and TgAb production as measured by RIA and ELISA was 1.5 - 3 times higher after 12 days' culture compared to 6 days' culture. Ig and TgAb production measured by PFC-assays at day 6 correlated positively to the results obtained by RIA and ELISA at day 12. PWM-induced TgAb secretion correlated positively to TgAb titres in serum. As judged by PFC, TgAb production was found in 8/9 patients; about 5% (range 0 - 7.9%) of the total PWM-stimulated IgG-secreting cells were involved in TgAb secretion. TgAb production as measured by ELISA and RIA was found in 6/9 patients. By reference to an affinity-purified human TgAb preparation, the TgAb secretion was about 0.7% (range 0 - 21.3%) of the total PWM-induced IgG secretion. (author)

  11. Imaging B lymphocytes in autoimmune inflammatory diseases

    International Nuclear Information System (INIS)

    Iodice, V.; Lauri, C.; Capriotti, G.; Lagana', B.; Germano, V.; D’Amelio, R.; Picchianti Diamanti, A.


    B cells arise from stem cells precursor and develop through a tightly regulated and selective process that lead to the generation of different B cell populations such as transitional, mature, memory and plasma cells. These B cell subsets can be identified using flow cytometry by the expression of specific surface antigens. The growing knowledge of the pivotal role played by B cells in the development and progression of autoimmune diseases combined with the advances in monoclonal antibody technology, led in the last years to the generation of different biological agents targeting B cells. In this context, nuclear medicine can offer the possibility to use a panel of biologic radiopharmaceuticals for molecular imaging of inflammatory diseases. Radiopharmaceuticals bind to their targets with high affinity and specificity and have an excellent imaging diagnostic potential for the evaluation of disease activity, selection and monitoring of immune therapies. Several molecules have been radiolabelled for the imaging of T lymphocytes whereas, by now, the anti CD20 rituximab is the only biological therapy targeting B cells that demonstrated to be efficiently radiolabelled and used to detect inflammation in autoimmune patients

  12. Effect of chloroquine on human lymphocyte proliferation

    DEFF Research Database (Denmark)

    Bygbjerg, Ib Christian; Flachs, H


    The effect of chloroquine on human blood mononuclear cells was studied. High concentrations of chloroquine in vitro profoundly suppressed the proliferation of mitogen- and antigen-stimulated cells, as indicated by decreased 14C-thymidine incorporation. Lower concentrations of chloroquine increase...... to large particulate antigens; the response to small antigens was not affected. The mode of action of chloroquine and the possible consequences of the findings for dosage of chloroquine when used for malaria prophylaxis is discussed.......The effect of chloroquine on human blood mononuclear cells was studied. High concentrations of chloroquine in vitro profoundly suppressed the proliferation of mitogen- and antigen-stimulated cells, as indicated by decreased 14C-thymidine incorporation. Lower concentrations of chloroquine increased...... the response to pokeweed mitogen. The response to concanavalin A and to various antigens was suppressed, especially the response to large particulate antigens. Oral intake of 300 mg of chloroquine base/week did not affect the lymphocyte proliferative responses. 600 mg of base/week decreased the response...

  13. Chronic lymphocytic leukaemia: An immunobiology approach

    Directory of Open Access Journals (Sweden)

    Kostareli Efterpi


    Full Text Available B cell chronic lymphocytic leukaemia (CLL is the most common adult leukaemia that follows an extremely variable clinical course. Several important prognostic parameters defining pathogenic and clinical subgroups of CLL have been identified and validated recently. The biological significance of immunoglobulin (Ig heavy chain variable region gene (IgHV mutational status and associated ZAP-70 over-expression, CD38 and chromosomal aberrations have enabled to identify patients at high risk for early disease progression and inferior survival. Moreover, studies of the B cell antigen receptor (BCR structure and receptor signaling have been most helpful in revealing some new aspects of the biology of this disease. In particular, the analysis of IG genes has revealed that the expressed IgHV/IgKV/IgLV gene repertoires of CLL cells differ from those of normal B cells. A further unique feature of the CLL IG repertoire is the existence of subsets of cases with "stereotyped" BCRs. Accumulating molecular and phenotypic data support the notion that CLL development and evolution is not a simple scholastic event and strongly indicates a role for antigen in driving the cell of origin for at least some subsets of CLL cases.

  14. Effect of interleukin-2 and methylprednisolone on in vitro transformation of uremic lymphocytes

    DEFF Research Database (Denmark)

    Langhoff, E; Ladefoged, J; Ødum, Niels


    The functional relationship in vitro between mitogen-induced lymphocyte transformation, lymphocyte response to interleukin-2 (IL-2) and steroid, and production of IL-2 was examined in patients with chronic renal failure on hemodialysis (HD) or on continuous ambulatory peritoneal dialysis (CAPD......). The lymphocyte responses to optimal stimulation with phytohemagglutinin, concanavalin A, and pokeweed mitogen were depressed in lymphocyte cultures from HD patients, while CAPD lymphocyte cultures responded normally. However, at suboptimal phytohemagglutinin stimulation both CAPD lymphocyte and HD lymphocyte...... responses were subnormal. Uremic lymphocyte cultures were more sensitive to the immunosuppressive effect of methylprednisolone. Addition of IL-2 normalized the phytohemagglutinin responses of suboptimally stimulated CAPD lymphocyte cultures and clearly improved the mitogen responses of the HD lymphocyte...

  15. Cell proliferation and radiosensitivity of cow lymphocytes in culture

    International Nuclear Information System (INIS)

    Modave, C.; Fabry, L.; Leonard, A.


    The harlequin-staining technique has been used to study, after PHA-stimulation, the cell proliferation of cow lymphocytes in culture and to assess the radiosensitivity in first mitosis cells. At the 48 h fixation time, only 34% of the cells are in first mitosis whereas 55% are already in second and 11% in third mitosis. The exposure of cow lymphocytes to 200 rad X-rays result in the production of 16% dicentric chromosomes in first mitosis cells [fr

  16. Latent childhood thyroid carcinoma in diffuse lymphocytic thyroiditis. (United States)

    Siegal, A; Mimouni, M; Kovalivker, M; Griffel, B


    Diffuse thyroid enlargement in a child is a rare presenting symptom of thyroid carcinoma. A papillary carcinoma may be hidden in a diffuse lymphocytic thyroiditis and should be carefully searched for during surgery. Furthermore, the finding, in frozen sections, of psammoma bodies in a lymphocytic thyroiditis should raise the suspicion of an occult malignant neoplasm. A case illustrating these diagnostic difficulties in a 5-year-old child is presented.

  17. Bare lymphocyte syndrome: imaging findings in an adult

    International Nuclear Information System (INIS)

    Bernaerts, A.; Vandevenne, J.E.; De Schepper, A.M.; Lambert, J.; De Clerck, L.S.


    Bare lymphocyte syndrome (BLS) is a rare primary immune disorder characterized by defective expression of human leukocyte antigen (HLA) on lymphocytes, often resulting in extensive and recurrent multi-organ infections. We describe a previously undiagnosed case of an adult woman who presented with radiological findings of severe bronchiectases, near-total granulomatous destruction of facial bones, and osteomyelitis. Diagnosis of BLS should be considered when evaluating children with unexplained bronchiectases or adults with long history of chronic multi-organ infections. (orig.)

  18. Real time imaging of live cell ATP leaking or release events by chemiluminescence microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yun [Iowa State Univ., Ames, IA (United States)


    The purpose of this research was to expand the chemiluminescence microscopy applications in live bacterial/mammalian cell imaging and to improve the detection sensitivity for ATP leaking or release events. We first demonstrated that chemiluminescence (CL) imaging can be used to interrogate single bacterial cells. While using a luminometer allows detecting ATP from cell lysate extracted from at least 10 bacterial cells, all previous cell CL detection never reached this sensitivity of single bacteria level. We approached this goal with a different strategy from before: instead of breaking bacterial cell membrane and trying to capture the transiently diluted ATP with the firefly luciferase CL assay, we introduced the firefly luciferase enzyme into bacteria using the modern genetic techniques and placed the CL reaction substrate D-luciferin outside the cells. By damaging the cell membrane with various antibacterial drugs including antibiotics such as Penicillins and bacteriophages, the D-luciferin molecules diffused inside the cell and initiated the reaction that produces CL light. As firefly luciferases are large protein molecules which are retained within the cells before the total rupture and intracellular ATP concentration is high at the millmolar level, the CL reaction of firefly luciferase, ATP and D-luciferin can be kept for a relatively long time within the cells acting as a reaction container to generate enough photons for detection by the extremely sensitive intensified charge coupled device (ICCD) camera. The result was inspiring as various single bacterium lysis and leakage events were monitored with 10-s temporal resolution movies. We also found a new way of enhancing diffusion D-luciferin into cells by dehydrating the bacteria. Then we started with this novel single bacterial CL imaging technique, and applied it for quantifying gene expression levels from individual bacterial cells. Previous published result in single cell gene expression quantification

  19. Detection of cardiac transplant rejection with radiolabeled lymphocytes

    International Nuclear Information System (INIS)

    Bergmann, S.R.; Lerch, R.A.; Carlson, E.M.; Saffitz, J.E.; Sobel, B.E.


    To determine whether rejections of cardiac transplants could be detected specifically and non-invasively by lymphocytes labeled with indium-111 (111In), we studied 36 allogeneic and 14 isogeneic heterotopic cardiac transplants in rats. Allogeneic grafts accumulated autologous 111In-lymphocytes, detectable scintigraphically 24 hours after i.v. injection of the labeled cells. At the time of peak histologic rejection, the allogeneic grafts accumulated 92. +/- 4.8 times more activity than the native hearts (determined by well counting). The tissue-to-blood ratio in the rejecting transplants was 3.7 +/- 2.2; total uptake by the graft was 2.9 +/- 2.1% of the injected dose. Autoradiography confirmed that graft radioactivity was associated with labeled lymphocytes. In contrast, isogeneic grafts showed no signs of rejection and did not accumulate radioactivity. Because conventionally isolated and labeled lymphocytes are often contaminated with platelets, we prepared both 111In-platelets and purified 111In-lymphocytes for use in additional experiments. Allogeneic grafts accumulated platelets and purified lymphocytes independently. Thus, deposition of immunologically active cells in the rejecting graft representing specific pathophysiologic events can be detected. The results suggest that rejection of cardiac transplants can be detected noninvasively, potentially facilitating objective early clinical detection of rejection and titration of antirejection therapy

  20. Analysis of cytotoxic effects of nickel on human blood lymphocytes. (United States)

    Zarei, Mohammad Hadi; Hosseini Shirazi, Seyed Farshad; Aghvami, Marjan; Salimi, Ahmad; Pourahmad, Jalal


    Nickel compounds possess many applications in different industrial processes. Human beings are exposed to nickel commonly through occupational exposure and food. Although a few studies so far have investigated the effects of nickel compounds on human lymphocytes, the complete mechanism of cytotoxicity of this metal on human lymphocytes is yet to be determined. The intention of this paper was to determine the cytotoxicity mechanism of water soluble NiCl 2 toward human lymphocytes using the accelerated cytotoxicity mechanisms screening (ACMS) technique. Human lymphocytes were isolated from the blood of healthy subjects based on Ficoll-Paque PLUS standard method. For the assessment of cell viability, lymphocytes were incubated with 0.05-1 mM NiCl 2 for 12 h. Determination of mechanistic parameters was performed 2, 4 and 6 h after treatment of cells with ½ EC50 12h , EC50 12h and 2EC50 12h of NiCl 2 . Our results demonstrate that cytotoxicity of NiCl 2 on human lymphocytes is associated with increased ROS formation, mitochondrial membrane potential collapse, glutathione depletion, lysosomal membrane damage, cellular proteolysis and activation of caspase-3 before cytotoxicity ensued.

  1. Mechanism of chlorphentermine-induced lymphocyte toxicity: initial investigations

    International Nuclear Information System (INIS)

    Sauers, L.J.; Wierda, D.; Reasor, M.J.


    Chlorphentermine (CP) inhibits the blastogenic response of mouse splenic and human peripheral blood lymphocytes to the T-cell mitogens, phytohemagglutinin (PHA) and concanavalin A (Con A). The purpose of these studies was to examine in vitro the mechanism mediating this immunosuppression. If mouse or human lymphocytes are pretreated with CP for 30 minutes, then stimulated with PHA, their blastogenic response is inhibited 80% and 45%, respectively. However, if CP is not added until 10 minutes or later following PHA stimulation, the inhibitory effect of the drug is essentially eliminated. The authors also determined that CP can potentiate Con A-induced agglutination of human lymphocytes. Enhanced agglutination can result from changes in the integrity of membrane phospholipids. Because changes in membrane phospholipid biochemistry characteristically occur within 10 minutes after mitogen-induced lymphocyte activation, the authors examined whether CP altered the incorporation of choline into cellular phospholipids. They found that CP decreases overall incorporation of 14 C-choline into cellular phospholipids of mouse lymphocytes by 45% during the first 4 hours of activation. These data suggest that the immunotoxicity associated with CP may be mediated by drug-induced changes at the membrane level that appear to occur early during lymphocyte activation

  2. Tuberculin purified protein derivative-reactive T cells in cord blood lymphocytes.


    Shiratsuchi, H; Tsuyuguchi, I


    Lymphocytes obtained from cord blood of newborn babies who were born of healthy mothers were studied in vitro for their responsiveness to purified protein derivative (PPD) of tuberculin. Cord blood lymphocytes proliferated in vitro by stimulation with PPD, despite wide variations in the results. Studies with fractionated lymphocytes revealed that PPD-responding cells belonged to E-rosetting, nylon wool-nonadherent T lymphocytes. Non-E-rosetting B lymphocytes alone did not proliferate at all a...

  3. A comparison of the neutrophil-lymphocyte, platelet-lymphocyte and monocyte-lymphocyte ratios in schizophrenia and bipolar disorder patients - a retrospective file review. (United States)

    Özdin, Selçuk; Sarisoy, Gökhan; Böke, Ömer


    Neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR) and monocyte-lymphocyte ratio (MLR) have recently been used as indicators of inflammation. Higher MLR and PLR values have been determined in the euthymic and manic periods in patients with bipolar disorder compared to a control group. High NLR values were determined in the only study investigating this ratio in schizophrenia patients. The purpose of this study was to compare NLR, PLR and MLR values and complete blood count elements in patients receiving treatment and hospitalized due to schizophrenic psychotic episode and bipolar disorder manic episode. All patients meeting the inclusion criteria among subjects receiving treatment and hospitalized due to schizophrenia-psychotic episode and bipolar affective disorder-manic episode at the Ondokuz Mayıs University Medical Faculty Psychiatry Department, Turkey, in 2012-2016 were included in our study. A total of 157 healthy donors were included as a control group. White blood cell (WBC), neutrophil, lymphocyte, platelet and monocyte numbers were noted retrospectively from complete blood counts at time of admission, and NLR, PLR and MLR were calculated from these. NLR, PLR and MLR values and platelet numbers in this study were higher and lymphocyte numbers were lower in bipolar disorder patients compared to the controls. Elevation in NLR, MLR and PLR values and neutrophil numbers and lower lymphocyte numbers were determined in schizophrenia patients compared to the controls. Higher NLR and MLR values were found in schizophrenia patients compared to bipolar disorder. Findings of our study supported the inflammation hypothesis for schizophrenia and bipolar disorder.

  4. Timely binding of IHF and Fis to DARS2 regulates ATP-DnaA production and replication initiation. (United States)

    Kasho, Kazutoshi; Fujimitsu, Kazuyuki; Matoba, Toshihiro; Oshima, Taku; Katayama, Tsutomu


    In Escherichia coli, the ATP-bound form of DnaA (ATP-DnaA) promotes replication initiation. During replication, the bound ATP is hydrolyzed to ADP to yield the ADP-bound form (ADP-DnaA), which is inactive for initiation. The chromosomal site DARS2 facilitates the regeneration of ATP-DnaA by catalyzing nucleotide exchange between free ATP and ADP bound to DnaA. However, the regulatory mechanisms governing this exchange reaction are unclear. Here, using in vitro reconstituted experiments, we show that two nucleoid-associated proteins, IHF and Fis, bind site-specifically to DARS2 to activate coordinately the exchange reaction. The regenerated ATP-DnaA was fully active in replication initiation and underwent DnaA-ATP hydrolysis. ADP-DnaA formed heteromultimeric complexes with IHF and Fis on DARS2, and underwent nucleotide dissociation more efficiently than ATP-DnaA. Consistently, mutant analyses demonstrated that specific binding of IHF and Fis to DARS2 stimulates the formation of ATP-DnaA production, thereby promoting timely initiation. Moreover, we show that IHF-DARS2 binding is temporally regulated during the cell cycle, whereas Fis only binds to DARS2 in exponentially growing cells. These results elucidate the regulation of ATP-DnaA and replication initiation in coordination with the cell cycle and growth phase. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  5. Interaction of cytochalasin D with actin filaments in the presence of ADP and ATP. (United States)

    Carlier, M F; Criquet, P; Pantaloni, D; Korn, E D


    Cytochalasin D strongly inhibits the faster components in the reactions of actin filament depolymerization and elongation in the presence of 10 mM Tris-Cl-, pH 7.8, 0.2 mM dithiothreitol, 1 mM MgCl2, 0.1 mM CaCl2, and 0.2 mM ATP or ADP. Assuming an exclusive and total capping of the barbed end by the drug, the kinetic parameters derived at saturation by cytochalasin D refer to the pointed end and are 10-15-fold lower than at the barbed end. In ATP, the critical concentration increases with cytochalasin D up to 12-fold its value when both ends are free; as a result of the lowering of the free energy of nucleation by cytochalasin D, short oligomers of F-actin exist just above and below the critical concentration. Cytochalasin D interacts strongly with the barbed ends independently of the ADP-G-actin concentration (K = 0.5 nM-1). In contrast, the affinity of cytochalasin D decreases cooperatively with increasing ATP-G-actin concentration. These data are equally well accounted for by two different models: either cytochalasin D binds very poorly to ATP-capped filament ends whose proportion increases with actin concentration, or cytochalasin D binds equally well to ATP-ends and ADP-ends and also binds to actin dimers in ATP but not in ADP. A linear actin concentration dependence of the rate of growth was found at the pointed end, consistent with the virtual absence of an ATP cap at that end.

  6. Cyclophilin D Promotes Brain Mitochondrial F1FO ATP Synthase Dysfunction in Aging Mice. (United States)

    Gauba, Esha; Guo, Lan; Du, Heng


    Brain aging is the known strongest risk factor for Alzheimer's disease (AD). In recent years, mitochondrial deficits have been proposed to be a common mechanism linking brain aging to AD. Therefore, to elucidate the causative mechanisms of mitochondrial dysfunction in aging brains is of paramount importance for our understanding of the pathogenesis of AD, in particular its sporadic form. Cyclophilin D (CypD) is a specific mitochondrial protein. Recent studies have shown that F1FO ATP synthase oligomycin sensitivity conferring protein (OSCP) is a binding partner of CypD. The interaction of CypD with OSCP modulates F1FO ATP synthase function and mediates mitochondrial permeability transition pore (mPTP) opening. Here, we have found that increased CypD expression, enhanced CypD/OSCP interaction, and selective loss of OSCP are prominent brain mitochondrial changes in aging mice. Along with these changes, brain mitochondria from the aging mice demonstrated decreased F1FO ATP synthase activity and defective F1FO complex coupling. In contrast, CypD deficient mice exhibited substantially mitigated brain mitochondrial F1FO ATP synthase dysfunction with relatively preserved mitochondrial function during aging. Interestingly, the aging-related OSCP loss was also dramatically attenuated by CypD depletion. Therefore, the simplest interpretation of this study is that CypD promotes F1FO ATP synthase dysfunction and the resultant mitochondrial deficits in aging brains. In addition, in view of CypD and F1FO ATP synthase alterations seen in AD brains, the results further suggest that CypD-mediated F1FO ATP synthase deregulation is a shared mechanism linking mitochondrial deficits in brain aging and AD.

  7. ATP-sensitive K(+-channels in muscle cells: features and physiological role

    Directory of Open Access Journals (Sweden)

    O. B. Vadzyuk


    Full Text Available ATP-sensitive K+-channels of plasma membranes belong to the inward rectifier potassium channels type. They are involved in coupling of electrical activity of muscle cell with its metabolic­ state. These channels are heterooctameric and consist of two types of subunits: four poreforming (Kir 6.х and four regulatory (SUR, sulfonylurea receptor. The Kir subunits contain highly selective K+ filter and provide for high-velocity K+ currents. The SUR subunits contain binding sites for activators and blockers and have metabolic sensor, which enables channel activation under conditions of metabolic stress. ATP blocks K+ currents through the ATP-sensitive K+-channels in the most types of muscle cells. However, functional activity of these channels does not depend on absolute concentration of ATP but on the АТР/ADP ratio and presence of Mg2+. Physiologically active substances, such as phosphatidylinositol bisphosphate and fatty acid esters can regulate the activity of these structures in muscle cells. Activation of these channels under ischemic conditions underlies their cytoprotective action, which results in prevention of Ca2+ overload in cytosol. In contrast to ATP-sensitive K+-channels of plasma membranes, the data regarding the structure and function of ATP-sensitive K+-channels of mitochondrial membrane are contradictory. Pore-forming subunits of this channel have not been firmly identified yet. ATP-sensitive K+ transport through the mitochondrial­ membrane is easily tested by different methods, which are briefly reviewed in this paper. Interaction of mitoKATP with physiological and pharmacological ligands is discussed as well.

  8. Evolutionary, kinetic and thermodynamic aspects on the bioenergetics of inorganic pyrophosphate (PPi) and adenosine triphosphate (ATP)

    International Nuclear Information System (INIS)

    Baltscheffsky, H.; Baltscheffsky, M.


    Energy barriers for energy carriers are of fundamental significance for the successful operation of the bioenergetic reactions in living cells. PPi and ATP are outstanding ''energy-rich'' examples of molecular ''energy currencies'' in biological systems, with kinetic barriers preventing excessively fast thermodynamically feasible hydrolysis from occurring. The barriers may be considered to facilitate the energy coupling roles of these phosphate compounds, which are to secure growth and maintain numerous other energy requiring functions. The enzymes involved in overcoming the energies of activation of the bioenergetic reactions have evolved to be very well tuned for their roles. Three aspects will be discussed in some detail. The first is the fact that ATP at neutral pH is considerably more energy-rich than PPi, which thus has been called a ''poor man's ATP''. This is exemplified by the kinetic and thermodynamic differences observed between the requirements for the photosynthetic formation of PPi and ATP in certain photobacterial chromatophores by varying levels of energy supply. At lower pH, PPi and ATP are equally energy-rich, which may be of significance for acidophiles. The second concerns the possible evolutionary significance of the finding that, in the dark, a pH gradient suffices to drive extensive PPi synthesis, whereas ATP synthesis requires both a pH gradient and a membrane potential (Strid et al, Biochim. Biophys. Acta 892 (1987) 236-244). Thirdly, PPi as the most plausible predecessor to ATP in the origin and early evolution of life, will be discussed. (author). Abstract only

  9. Permeability transition in human mitochondria persists in the absence of peripheral stalk subunits of ATP synthase. (United States)

    He, Jiuya; Carroll, Joe; Ding, Shujing; Fearnley, Ian M; Walker, John E


    The opening of a nonspecific channel, known as the permeability transition pore (PTP), in the inner membranes of mitochondria can be triggered by calcium ions, leading to swelling of the organelle, disruption of the inner membrane and ATP synthesis, and cell death. Pore opening can be inhibited by cyclosporin A mediated via cyclophilin D. It has been proposed that the pore is associated with the dimeric ATP synthase and the oligomycin sensitivity conferral protein (OSCP), a component of the enzyme's peripheral stalk, provides the site at which cyclophilin D interacts. Subunit b contributes a central α-helical structure to the peripheral stalk, extending from near the top of the enzyme's catalytic domain and crossing the membrane domain of the enzyme via two α-helices. We investigated the possible involvement of the subunit b and the OSCP in the PTP by generating clonal cells, HAP1-Δb and HAP1-ΔOSCP, lacking the membrane domain of subunit b or the OSCP, respectively, in which the corresponding genes, ATP5F1 and ATP5O , had been disrupted. Both cell lines preserve the characteristic properties of the PTP; therefore, the membrane domain of subunit b does not contribute to the PTP, and the OSCP does not provide the site of interaction with cyclophilin D. The membrane subunits ATP6, ATP8, and subunit c have been eliminated previously from possible participation in the PTP; thus, the only subunits of ATP synthase that could participate in pore formation are e, f, g, diabetes-associated protein in insulin-sensitive tissues (DAPIT), and the 6.8-kDa proteolipid.

  10. Selective toxicity of persian gulf sea cucumber holothuria parva on human chronic lymphocytic leukemia b lymphocytes by direct mitochondrial targeting. (United States)

    Salimi, Ahmad; Motallebi, Abbasali; Ayatollahi, Maryam; Seydi, Enayatollah; Mohseni, Ali Reza; Nazemi, Melika; Pourahmad, Jalal


    Natural products isolated from marine environment are well known for their pharmacodynamic potential in diversity of disease treatments such as cancer or inflammatory conditions. Sea cucumbers are one of the marine animals of the phylum Echinoderm. Many studies have shown that the sea cucumber contains antioxidants and anti-cancer compounds. Chronic lymphocytic leukemia (CLL) is a disease characterized by the relentless accumulation of CD5 + B lymphocytes. CLL is the most common leukemia in adults, about 25-30% of all leukemias. In this study B lymphocytes and their mitochondria (cancerous and non-cancerous) were obtained from peripheral blood of human subjects and B lymphocyte cytotoxicity assay, and caspase 3 activation along with mitochondrial upstream events of apoptosis signaling including reactive oxygen species (ROS) production, collapse of mitochondrial membrane potential (MMP) and mitochondrial swelling were determined following the addition of Holothuria parva extract to both cancerous and non-cancerous B lymphocytes and their mitochondria. Our in vitro finding showed that mitochondrial ROS formation, MMP collapse, and mitochondrial swelling and cytochrome c release were significantly (P < 0.05) increased after addition of different concentrations of H. parva only in cancerous BUT NOT normal non-cancerous mitochondria. Consistently, different concentrations of H. parva significantly (P < 0.05) increased cytotoxicity and caspase 3 activation only in cancerous BUT NOT normal non-cancerous B lymphocytes. These results showed that H. parva methanolic extract has a selective mitochondria mediated apoptotic effect on chronic lymphocytic leukemia B lymphocytes hence may be promising in the future anticancer drug development for treatment of CLL. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1158-1169, 2017. © 2016 Wiley Periodicals, Inc.

  11. Old beagle dogs have lower faecal concentrations of some fermentation products and lower peripheral lymphocyte counts than young adult beagles. (United States)

    Gomes, Márcia de Oliveira Sampaio; Beraldo, Mariana Casteleti; Putarov, Thaila Cristina; Brunetto, Márcio Antônio; Zaine, Leandro; Glória, Maria Beatriz Abreu; Carciofi, Aulus Cavalieri


    The effects of age on microbiota composition, gut fermentation end-product formation and peripheral lymphocyte numbers were compared between old and young adult Beagle dogs fed four kibble diets differing in yeast cell wall contents. The experiment had a double 4 × 4 Latin square design, one with four mature dogs (4 years old) and the other with four old dogs (10 years old), with four replicates (diets) per dog. In each period a 15 d adaptation period preceded a 5 d total collection of faeces for the digestibility trial. On day 21, fresh faecal samples were collected for the determination of bacterial enumeration, pH, biogenic amine and short-chain fatty acid. Flow cytometry was used for immunophenotypic evaluation. Dogs were fed four kibble diets with similar composition with 0, 0.15, 0.30 and 0.45 % of yeast cell wall (as-fed), respectively. Data were evaluated using general linear models of Statistical Analysis Systems statistical software (P 0.15). Faecal concentrations of butyrate, histamine, agmatine and spermine were lower (P ≤ 0.05) and faecal pH was higher (P = 0.03) in older dogs than in mature adult dogs, suggesting an alteration in bacterial metabolic activity, or in the rate of intestinal absorption of these compounds. Concentrations of T-lymphocytes, T-cytotoxic lymphocytes and B-lymphocytes were also lower (P ≤ 0.01) in older dogs than in mature adult dogs. The study confirmed alterations in peripheral lymphocytes and revealed a reduced concentration of some fermentation end products in the colon of old dogs.

  12. Role of oxidative stress, mitochondrial membrane potential, and calcium homeostasis in human lymphocyte death induced by nickel carbonate hydroxide in vitro

    Energy Technology Data Exchange (ETDEWEB)

    M' Bemba-Meka, Prosper [Faculty of Medicine, Universite de Montreal, QC (Canada); University of Louisville, Department of Pharmacology and Toxicology, Center for Genetics and Molecular Medicine, Louisville, KY (United States); Lemieux, Nicole [Universite de Montreal, Department of Pathology and Cellular Biology, Main Station, P.O. Box 6128, Montreal, QC (Canada); Chakrabarti, Saroj K. [Faculty of Medicine, Universite de Montreal, QC (Canada)


    When isolated human lymphocytes were treated in vitro with various concentrations of soluble form of nickel carbonate hydroxide (NiCH) (0-1 mM), at 37 C for 4 h, both concentration- and time-dependent effects of NiCH on lymphocyte death were observed. Increased generation of hydrogen peroxide (H{sub 2}O{sub 2}), superoxide anion (O{sub 2} {sup -}), depletion of both no protein (NP-) and protein (P-) sulfhydryl (SH) contents and lipid peroxidation (LPO) were induced by NiCH. Pretreatment of lymphocytes with either catalase (H{sub 2}O{sub 2} scavenger), or deferoxamine (DFO) (iron chelator), or excess glutathione (GSH) (an antioxidant) not only significantly reduced the NiCH-induced generation of H{sub 2}O{sub 2} and LPO, but also increased the NP-SH and P-SH contents initially reduced by NiCH. NiCH-induced generation of excess O{sub 2} {sup -} but not excess LPO was significantly reduced by pretreatment with superoxide dismutase (SOD). NiCH-induced lymphocyte death was significantly prevented by pre-treatment with either catalase, or dimethylthiourea/mannitol (hydroxyl radical scavengers), or DFO, or excess GSH/N-acetylcysteine. NiCH-induced lymphocyte death was also significantly prevented by pretreatment with excess SOD. Thus, various types of oxidative stresses play an important role in NiCH-induced lymphocyte death. Cotreatment with cyclosporin A, a specific inhibitor of alteration in mitochondrial membrane potential ({delta}{psi}{sub m}), not only inhibited NiCH-induced alteration in {delta}{psi}{sub m}, but also significantly prevented Ni-compound-induced lymphocyte death. Furthermore, NiCH-induced destabilization of cellular calcium homeostasis. As such, NiCH-induced lymphocyte death was significantly prevented by modulating intracellular calcium fluxes such as Ca{sup 2+} channel blockers and intracellular Ca{sup 2+} antagonist. Thus, the mechanism of NiCH (soluble form)-induced activation of lymphocyte death signalling pathways involves not only the excess

  13. Activity of clinically relevant antimalarial drugs on Plasmodium falciparum mature gametocytes in an ATP bioluminescence "transmission blocking" assay.

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    Joël Lelièvre

    Full Text Available BACKGROUND: Current anti-malarial drugs have been selected on the basis of their activity against the symptom-causing asexual blood stage of the parasite. Which of these drugs also target gametocytes, in the sexual stage responsible for disease transmission, remains unknown. Blocking transmission is one of the main strategies in the eradication agenda and requires the identification of new molecules that are active against gametocytes. However, to date, the main limitation for measuring the effect of molecules against mature gametocytes on a large scale is the lack of a standardized and reliable method. Here we provide an efficient method to produce and purify mature gametocytes in vitro. Based on this new procedure, we developed a robust, affordable, and sensitive ATP bioluminescence-based assay. We then assessed the activity of 17 gold-standard anti-malarial drugs on Plasmodium late stage gametocytes. METHODS AND FINDINGS: Difficulties in producing large amounts of gametocytes have limited progress in the development of malaria transmission blocking assays. We improved the method established by Ifediba and Vanderberg to obtain viable, mature gametocytes en masse, whatever the strain used. We designed an assay to determine the activity of antimalarial drugs based on the intracellular ATP content of purified stage IV-V gametocytes after 48 h of drug exposure in 96/384-well microplates. Measurements of drug activity on asexual stages and cytotoxicity on HepG2 cells were also obtained to estimate the specificity of the active drugs. CONCLUSIONS: The work described here represents another significant step towards determination of the activity of new molecules on mature gametocytes of any strain with an automated assay suitable for medium/high-throughput screening. Considering that the biology of the forms involved in the sexual and asexual stages is very different, a screen of our 2 million-compound library may allow us to discover novel anti

  14. Associations between lifestyles and neutrophil-lymphocyte and platelet-lymphocyte ratios in colorectal cancer. (United States)

    Hong, Chuyuan; Wei, Yisheng; Jiang, Jianxin; Zhao, Chuxiong; Liang, Guojian; Wang, Guoqiang; Yang, Hui


    To explore the etiology of the neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) abnormalities in colorectal cancer. In total, 230 patients with histopathologically confirmed colorectal cancer from August 2009 to August 2011 were recruited to our study. The associations between lifestyles (smoking, alcohol and pickled food consumption) and pretreatment NLR and PLR were estimated using the Kruskal-Wallis tests and linear regression model. The Kruskal-Wallis test showed a significant association between pickled food intake and pretreatment NLR but not PLR (P = 0.002, 0.057, respectively). Pairwise comparisons showed that, compared with those with a moderately frequent (2-3 times/week) and an infrequent (≤ once a week) intake of pickled food, high frequency (≥ four times/week) consumption of pickled food had a higher pretreatment NLR (P = 0.01, 0.007, respectively). Multivariate linear regression analysis showed pretreatment NLR increased significantly in high frequency (≥ four times/week) consumption of pickled food (P frequency intake of pickled food possibly contributes to higher NLR, which may reflect a systemic inflammatory response in colorectal cancer. © 2013 Wiley Publishing Asia Pty Ltd.

  15. Leucine-Enriched Essential Amino Acids Augment Muscle Glycogen Content in Rats Seven Days after Eccentric Contraction

    Directory of Open Access Journals (Sweden)

    Hiroyuki Kato


    Full Text Available Eccentric contractions induce muscle damage, which impairs recovery of glycogen and adenosine tri-phosphate (ATP content over several days. Leucine-enriched essential amino acids (LEAAs enhance the recovery in muscles that are damaged after eccentric contractions. However, the role of LEAAs in this process remains unclear. We evaluated the content in glycogen and high energy phosphates molecules (phosphocreatine (PCr, adenosine di-phosphate (ADP and ATP in rats that were following electrically stimulated eccentric contractions. Muscle glycogen content decreased immediately after the contraction and remained low for the first three days after the stimulation, but increased seven days after the eccentric contraction. LEAAs administration did not change muscle glycogen content during the first three days after the contraction. Interestingly, however, it induced a further increase in muscle glycogen seven days after the stimulation. Contrarily, ATP content decreased immediately after the eccentric contraction, and remained lower for up to seven days after. Additionally, LEAAs administration did not affect the ATP content over the experimental period. Finally, ADP and PCr levels did not significantly change after the contractions or LEAA administration. LEAAs modulate the recovery of glycogen content in muscle after damage-inducing exercise.

  16. Effects of acupuncture on peripheral T lymphocyte subpopulation and amounts of cerebral catecholamines in mice. (United States)

    Okumura, M; Toriizuka, K; Iijima, K; Haruyama, K; Ishino, S; Cyong, J C


    The aim of this study was to investigate the effects of acupuncture on peripheral lymphocyte subpopulations and cerebral catecholamines. In order to examine the effects of acupuncture, two experiments were performed. Experiment 1: Eighteen female mice (strain; C57BL/6) at the age of 7 weeks were divided three groups, (a) sham operated (control; n=6), (b) ovariectomized (OVX; n=6), and (c) ovariectomized and stimulated by subcutaneous needles on acupuncture point, Shenshu (BL23) at the both sides of the back for 20 days (OVX+Acu; n=6). These animals were sacrificed at 20 days after needle insertion, and the splenic lymphoid cells were examined by two-color flow cytometry, using monoclonal antibodies (mAb) to the cell surface antigens, CD3, CD4, CD8a and NK1.1 (CD56). In the ovariectomized (OVX) group, the peripheral CD4/CD8 ratio was significantly increased and the ratio of natural killer (NK) cells (CD3-NK1.1+; CD3 negative, NK1.1 positive) to T lymphocytes was decreased compared to the sham control group. In the ovariectomized with needle insertion (OVX+Acu) group, the CD4/CD8 ratio was reduced, but the NK cells ratio was not changed compared to the OVX group. Experiment 2: To investigate the acute effects of subcutaneous needle insertion, male C57BL/6 mice (7 weeks old) were used (n=6, each group). The acupuncture points Shen-shu (BL23) on the backs of the male mice were also stimulated by subcutaneous needles for 3 and 7 days. As a result, the CD4/CD8 ratio was significantly decreased at day 3 and day 7, compared to the control group. On the other hand the NK cells ratio and activated T-cells were increased at day 7. The mitogenic activities in the splenic lymphocytes were also increased by acupuncture stimulation at day 3. Catecholamine contents in the hippocampus were measured by high performance liquid chromatography with the electro-chemical detector (ECD-HPLC) method. No significant change was observed in either dopamine contents or norepinephrine; however


    Directory of Open Access Journals (Sweden)

    A. A. Savchenko


    Full Text Available The aim of this study was to investigate phenotypic profile of B lymphocytes in peripheral blood of the patients with chronic endometritis and adnexitis. The study involved 89 women in their reproductive age (18 to 45 years with chronic endometritis (48 cases and adnexitis (41 cases. Ninety-eight healthy agematched women participated as a control group. Phenotypic B-cell subpopulations were analyzed by flow cytometry performed with direct immunofluorescent staining of peripheral cells from whole blood using the following antibody panel: CD5-FITC/CD23-PE/CD19-ECD/CD45-PC5/CD27-PC7. A significantly reduced B-lymphocyte content was revealed in peripheral blood of women with chronic endometritis and adnexitis. The reduced cell numbers occurred due to reduced B2 (main fraction of B-lymphocytes and as B1 cells (minor fraction which determines insufficient reactivity of specific humoral immune response, including immune reactions at the mucous membranes. However, percentage of B2-lymphocytes was decreased only in endometriosis, whereas patients with adnexitis showed decrease in both relative and absolute counts of this B cell subpopulation. A decreased content of naive B-cells in the peripheral blood is another feature of the B cell phenotypic profile in chronic endometritis and adnexitis. Moreover, the drop of the naive B-cell levels in patients with adnexitis proved to be more pronounced than in persons with endometritis. Expression of CD23- antigen (a low-affinity receptor for IgE has been investigated as a functional marker of B cells. All the studied peripheral B cell subpopulations expressing CD23 were decreased in the patients with chronic endometritis. The numbers of different B cell fractions expressing CD23 antigen were also reduced in the women with chronic adnexitis as compared to the levels detected in patients with chronic endometritis. Alterations of the B-cell immunity were more pronounced in chronic adnexitis, due to more extensive

  18. Ibrutinib for treatment of chronic lymphocytic leukemia. (United States)

    Vela, Cory M; McBride, Ali; Jaglowski, Samantha M; Andritsos, Leslie A


    The pharmacology, pharmacokinetics, pharmacodynamics, clinical efficacy, and safety of ibrutinib are described. Ibrutinib is a first-in-class oral inhibitor of Bruton tyrosine kinase (BTK) approved for treatment of relapsed chronic lymphocytic leukemia (CLL). Ibrutinib blocks downstream signaling of the B-cell receptor, disrupting stromal microenvironment interactions and B-cell cytokine signaling. BTK inhibition has been shown to be effective in relapsed or refractory CLL. A recent Phase III study evaluated ibrutinib (420 mg daily) versus ofatumumab (consistent with labeling) in relapsed or refractory CLL with a primary endpoint of progression free survival (PFS, n = 391). After a median follow-up period of 9.4 months, a PFS was not attained in ibrutinib-treated individuals with and without deletion 17p. In contrast, ofatumumab-treated individuals experienced a PFS of 8.1 months and those with deletion 17p experienced a PFS of 5.8 months. Major hemorrhage was reported in 2 (1%) patients treated with ibrutinib, and a total of 8 (4%) patients discontinued treatment due to toxicity or adverse reactions. Partial response or partial response with lymphocytosis was achieved in 63% of ibrutinib-treated individuals as determined by independent assessments. Overall, ibrutinib reduced the rate of mortality by 57%. Ibrutinib is a first-in-class, orally active, irreversible BTK inhibitor with a novel mechanism of action. This unique mechanism of action and high overall response rates observed in clinical trials make ibrutinib an attractive second-line option in patients who have disease progression while receiving monoclonal antibody therapy or chemoimmunotherapy. Copyright © 2016 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

  19. Current Treatment of Chronic Lymphocytic Leukemia. (United States)

    Jamroziak, Krzysztof; Puła, Bartosz; Walewski, Jan


    A number of new treatment options have recently emerged for chronic lymphocytic leukemia (CLL) patients, including the Bruton's tyrosine kinase (BTK) inhibitor ibrutinib, phosphatidylinositol-3-kinase (PI3K) delta isoform inhibitor idelalisib combined with rituximab, the Bcl-2 antagonist venetoclax, and the new anti-CD20 antibodies obinutuzumab and ofatumumab. Most of these agents are already included into treatment algorithms defined by international practice guidelines, but more clinical investigations are needed to answer still remaining questions. Ibrutinib was proven as a primary choice for patients with the TP53 gene deletion/mutation, who otherwise have no active treatment available. Idelalisib with rituximab is also an active therapy, but due to increased risk of serious infections, its use in first-line treatment is limited to patients for whom ibrutinib is not an option. A new indication for ibrutinib was recently approved for older patients with comorbidities, as an alternative to the already existing indication for chlorambucil with obinutuzumab. The use of kinase inhibitors is already well established in recurrent/refractory disease. Immunochemotherapy with fludarabine, cyclophosphamide, rituximab (FCR) remains a major first-line option for many CLL patients without the TP53 gene deletion/mutation, and who have no significant comorbidities or history of infections, and is particularly effective in patients with favorable features including mutated IGHV status. There are a number of issues regarding novel therapies for CLL that need further investigation such as optimum duration of treatment with kinase inhibitors, appropriate sequencing of novel agents, mechanisms of resistance to inhibitors and response to class switching after treatment failure, along with the potential role of combinations of targeted agents.


    Directory of Open Access Journals (Sweden)

    Patrizia Chiusolo


    Full Text Available

    Even if Chronic lymphocytic leukemia (CLL often has an indolent behavior with good responsiveness to cytoreductive treatment, about 20% of the patients, so called "poor-risk" patients, show an aggressive course and die within a few years despite early intensive therapies. Criteria for poor-risk disease according to the European Bone Marrow Transplantation (EBMT CLL Transplant Consensus are: purine analogue refractoriness, early relapse after purine analogue combination therapy, CLL with p53 lesion requiring treatment.

    Allogeneic transplant has potential curative role in CLL, however burden with very  high transplant related mortality (TRM rates of 38-50%:

    A major advance in reducing the short-term morbidity and mortality of allogeneic stem cell transplantation (SCT has been the introduction of non-myeloablative or reduced intensity conditioning (RIC regimens to allow engraftment of allogeneic stem cells. There is no doubt that the crucial therapeutic principle of allo-SCT in CLL is graft versus leukemia (GVL activity.

    The major complications of allogeneic SCT in CLL are: chronic graft-versus-host-disease (GVHD affecting quality of life, high graft rejection and infection rates rates correlated with preexisting immunosuppression. Disease relapse remains the major cause of failure after RIC allo-HCT in CLL patients.

    Sensitive minimal residual disease (MRD quantification has strong prognostic impact after transplant.