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Sample records for matrix acid stimulation

  1. Ultrasound stimulated release of gallic acid from chitin hydrogel matrix

    International Nuclear Information System (INIS)

    Jiang, Huixin; Kobayashi, Takaomi

    2017-01-01

    Ultrasound (US) stimulated drug release was examined in this study using a chitin hydrogel matrix loaded with gallic acid (GA), a drug used for wound healing and anticancer. Using phase inversion, GA-chitin hydrogels were prepared from chitin-dimethylacetamide (DMAc)/lithium chloride (LiCl) solution in the presence of GA, with 24 h exposure of the solution to water vapor. The GA release from the GA-chitin hydrogel was examined under different US powers of 0–30 W at 43 kHz. The effects of GA loading amounts in the hydrogels (0.54, 0.43, and 0.25 mg/cm 3 ) and chitin concentrations (0.1, 0.5, and 1 wt%) on the release behaviors were recorded under 43 kHz US exposure at 30 W. Results show that US accelerated the release efficiencies for all samples. Furthermore, the release efficiency increased concomitantly with increasing US power, GA loading amount, and decrease of the chitin concentration. The highest release rate of 0.74 μg/mL·min was obtained from 0.54 mg/cm 3 of GA-loaded hydrogel fabricated from a 0.1 wt% chitin mixture solution under 43 kHz US exposure at 30 W: nine times higher than that of the sample without US exposure. The hydrogel viscoelasticity demonstrated that the US irradiation rigidified the material. FT-IR showed that US can break the hydrogen bonds in the GA-chitin hydrogels. - Highlights: • Ultrasound (US) stimulated Gallic acid (GA) release from chitin hydrogel was studied. • The release efficiency of GA from chitin hydrogel increased nine times when irradiated by 43 kHz US compared with the sample without US. • Generalized 2D correlation and deconvolution study of FT-IR showed that US could promote the GA release by breaking hydrogen bonds.

  2. Ultrasound stimulated release of gallic acid from chitin hydrogel matrix

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Huixin; Kobayashi, Takaomi, E-mail: takaomi@nagaokaut.ac.jp

    2017-06-01

    Ultrasound (US) stimulated drug release was examined in this study using a chitin hydrogel matrix loaded with gallic acid (GA), a drug used for wound healing and anticancer. Using phase inversion, GA-chitin hydrogels were prepared from chitin-dimethylacetamide (DMAc)/lithium chloride (LiCl) solution in the presence of GA, with 24 h exposure of the solution to water vapor. The GA release from the GA-chitin hydrogel was examined under different US powers of 0–30 W at 43 kHz. The effects of GA loading amounts in the hydrogels (0.54, 0.43, and 0.25 mg/cm{sup 3}) and chitin concentrations (0.1, 0.5, and 1 wt%) on the release behaviors were recorded under 43 kHz US exposure at 30 W. Results show that US accelerated the release efficiencies for all samples. Furthermore, the release efficiency increased concomitantly with increasing US power, GA loading amount, and decrease of the chitin concentration. The highest release rate of 0.74 μg/mL·min was obtained from 0.54 mg/cm{sup 3} of GA-loaded hydrogel fabricated from a 0.1 wt% chitin mixture solution under 43 kHz US exposure at 30 W: nine times higher than that of the sample without US exposure. The hydrogel viscoelasticity demonstrated that the US irradiation rigidified the material. FT-IR showed that US can break the hydrogen bonds in the GA-chitin hydrogels. - Highlights: • Ultrasound (US) stimulated Gallic acid (GA) release from chitin hydrogel was studied. • The release efficiency of GA from chitin hydrogel increased nine times when irradiated by 43 kHz US compared with the sample without US. • Generalized 2D correlation and deconvolution study of FT-IR showed that US could promote the GA release by breaking hydrogen bonds.

  3. Well screening for matrix stimulation treatments

    International Nuclear Information System (INIS)

    Saavedra, N; Solano, R; Gidley, J; Reyes, C.A; Rodriguez; Kondo, F; Hernandez, J

    1998-01-01

    Matrix acidizing is a stimulation technique only applicable to wells with surrounding damage. It is therefore very important to differentiate the real formation damage from the damage caused by flow Ni dynamic effects. The mechanical damage corresponds to flow restrictions caused by partial penetration, poor perforation as well as to reduce diameters of the production tubing. The dynamic effects are generated by inertia caused by high flow rates and high-pressure differentials. A common practice in our oil fields is to use a general formulation as acid treatment, most of the times without previous lab studies that guarantee the applicability of the treatment in the formation. Additionally, stimulation is randomly applied even treating undamaged wells with negative results and in the best of the cases, loss of the treatment. The selection of the well for matrix stimulation is an essential factor for the success of the treatment. Selection is done through the evaluation of the skin factor (S) and of the economic benefits of reducing the skin in comparison to the cost of the work. The most appropriate tool for skin evaluation is a good pressure test where the radial flow period can be identified. Nevertheless, we normally find-outdated tests most of the times taken with inaccurate tools. The interpretation problem is worsened by completions in which there is simultaneous production from several sand packages and it is difficult to individually differentiate damage factors. This works states a procedure for the selection of wells appropriate for stimulation; it also proposes a method to evaluate the skin factor when there are no accurate interpretations of the pressure tests. A new and increasingly applied methodology to treat wells with high water cuts, which are usually discarded due to the risk of stimulating water zones, is also mentioned

  4. Formic acid dimers in a nitrogen matrix

    Science.gov (United States)

    Lopes, Susy; Fausto, Rui; Khriachtchev, Leonid

    2018-01-01

    Formic acid (HCOOH) dimers are studied by infrared spectroscopy in a nitrogen matrix and by ab initio calculations. We benefit from the use of a nitrogen matrix where the lifetime of the higher-energy (cis) conformer is very long (˜11 h vs. 7 min in an argon matrix). As a result, in a nitrogen matrix, a large proportion of the cis conformer can be produced by vibrational excitation of the lower-energy (trans) conformer. Three trans-trans, four trans-cis, and three cis-cis dimers are found in the experiments. The spectroscopic information on most of these dimers is enriched compared to the previous studies in an argon matrix. The cis-cis dimers of ordinary formic acid (without deuteration) are reported here for the first time. Several conformational processes are obtained using selective excitation by infrared light, some of them also for the first time. In particular, we report on the formation of cis-cis dimers upon vibrational excitation of trans-cis dimers. Tunneling decays of several dimers have been detected in the dark. The tunneling decay of cis-cis dimers of formic acid as well as the stabilization of cis units in cis-cis dimers is also observed for the first time.

  5. Stimulated light emission in a dielectrically disordered composite porous matrix

    Science.gov (United States)

    Gross, E.; Künzner, N.; Diener, J.; Fujii, Minoru; Timoshenko, V. Yu.; Kovalev, D.

    2005-06-01

    We report on a medium exhibiting extremely efficient light scattering properties: a liquid network formed in a porous matrix. Liquid fragments confined in the solid matrix result in a random fluctuation of the dielectric function and act as scattering objects for photons. The optical scattering efficiency is defined by the filling factor of the liquid in the pores and its dielectric constant. The spectral dependence of the scattering length of photons indicates that the phenomenon is governed by a Mie-type scattering mechanism. The degree of the dielectric disorder of the medium, i.e. the level of opacity is tunable by the ambient vapor pressure of the dielectric substance. In the strongest scattering regime the scattering length of photons is found to be in the micrometer range. By incorporation of dye molecules in the voids of the porous layer a system exhibiting optical gain is realized. In the multiple scattering regime the optical path of diffusively propagating photons is enhanced and light amplification through stimulated emission occurs: a strong intensity enhancement of the dye emission accompanied by significant spectral narrowing is observed above the excitation threshold for a layer being in the opalescence state.

  6. Fragmentation of extracellular matrix by hypochlorous acid

    DEFF Research Database (Denmark)

    Woods, Alan A; Davies, Michael Jonathan

    2003-01-01

    /chloramide decomposition, with copper and iron ions being effective catalysts, and decreased by compounds which scavenge chloramines/chloramides, or species derived from them. The effect of such matrix modifications on cellular behaviour is poorly understood, though it is known that changes in matrix materials can have...... profound effects on cell adhesion, proliferation, growth and phenotype. The observed matrix modifications reported here may therefore modulate cellular behaviour in diseases such as atherosclerosis where MPO-derived oxidants are generated....

  7. Muscarinic receptor agonists stimulate matrix metalloproteinase 1-dependent invasion of human colon cancer cells

    International Nuclear Information System (INIS)

    Raufman, Jean-Pierre; Cheng, Kunrong; Saxena, Neeraj; Chahdi, Ahmed; Belo, Angelica; Khurana, Sandeep; Xie, Guofeng

    2011-01-01

    Highlights: ► Muscarinic receptor agonists stimulated robust human colon cancer cell invasion. ► Anti-matrix metalloproteinase1 antibody pre-treatment blocks cell invasion. ► Bile acids stimulate MMP1 expression, cell migration and MMP1-dependent invasion. -- Abstract: Mammalian matrix metalloproteinases (MMPs) which degrade extracellular matrix facilitate colon cancer cell invasion into the bloodstream and extra-colonic tissues; in particular, MMP1 expression correlates strongly with advanced colon cancer stage, hematogenous metastasis and poor prognosis. Likewise, muscarinic receptor signaling plays an important role in colon cancer; muscarinic receptors are over-expressed in colon cancer compared to normal colon epithelial cells. Muscarinic receptor activation stimulates proliferation, migration and invasion of human colon cancer cells. In mouse intestinal neoplasia models genetic ablation of muscarinic receptors attenuates carcinogenesis. In the present work, we sought to link these observations by showing that MMP1 expression and activation plays a mechanistic role in muscarinic receptor agonist-induced colon cancer cell invasion. We show that acetylcholine, which robustly increases MMP1 expression, stimulates invasion of HT29 and H508 human colon cancer cells into human umbilical vein endothelial cell monolayers – this was abolished by pre-incubation with atropine, a non-selective muscarinic receptor inhibitor, and by pre-incubation with anti-MMP1 neutralizing antibody. Similar results were obtained using a Matrigel chamber assay and deoxycholyltaurine (DCT), an amidated dihydroxy bile acid associated with colon neoplasia in animal models and humans, and previously shown to interact functionally with muscarinic receptors. DCT treatment of human colon cancer cells resulted in time-dependent, 10-fold increased MMP1 expression, and DCT-induced cell invasion was also blocked by pre-treatment with anti-MMP1 antibody. This study contributes to understanding

  8. Muscarinic receptor agonists stimulate matrix metalloproteinase 1-dependent invasion of human colon cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Raufman, Jean-Pierre, E-mail: jraufman@medicine.umaryland.edu [Division of Gastroenterology and Hepatology, University of Maryland School of Medicine, Baltimore, MD (United States); Cheng, Kunrong; Saxena, Neeraj; Chahdi, Ahmed; Belo, Angelica; Khurana, Sandeep; Xie, Guofeng [Division of Gastroenterology and Hepatology, University of Maryland School of Medicine, Baltimore, MD (United States)

    2011-11-18

    Highlights: Black-Right-Pointing-Pointer Muscarinic receptor agonists stimulated robust human colon cancer cell invasion. Black-Right-Pointing-Pointer Anti-matrix metalloproteinase1 antibody pre-treatment blocks cell invasion. Black-Right-Pointing-Pointer Bile acids stimulate MMP1 expression, cell migration and MMP1-dependent invasion. -- Abstract: Mammalian matrix metalloproteinases (MMPs) which degrade extracellular matrix facilitate colon cancer cell invasion into the bloodstream and extra-colonic tissues; in particular, MMP1 expression correlates strongly with advanced colon cancer stage, hematogenous metastasis and poor prognosis. Likewise, muscarinic receptor signaling plays an important role in colon cancer; muscarinic receptors are over-expressed in colon cancer compared to normal colon epithelial cells. Muscarinic receptor activation stimulates proliferation, migration and invasion of human colon cancer cells. In mouse intestinal neoplasia models genetic ablation of muscarinic receptors attenuates carcinogenesis. In the present work, we sought to link these observations by showing that MMP1 expression and activation plays a mechanistic role in muscarinic receptor agonist-induced colon cancer cell invasion. We show that acetylcholine, which robustly increases MMP1 expression, stimulates invasion of HT29 and H508 human colon cancer cells into human umbilical vein endothelial cell monolayers - this was abolished by pre-incubation with atropine, a non-selective muscarinic receptor inhibitor, and by pre-incubation with anti-MMP1 neutralizing antibody. Similar results were obtained using a Matrigel chamber assay and deoxycholyltaurine (DCT), an amidated dihydroxy bile acid associated with colon neoplasia in animal models and humans, and previously shown to interact functionally with muscarinic receptors. DCT treatment of human colon cancer cells resulted in time-dependent, 10-fold increased MMP1 expression, and DCT-induced cell invasion was also blocked by pre

  9. Optimising the Effect of Stimulants on Citric Acid Production from ...

    African Journals Online (AJOL)

    Additives such as low molecular weight alcohols, trace metals, phytate, lipids etc have been reported to stimulate citric acid production. Hence the objective of this study was to investigate the effect of stimulating the metabolic activity of Aspergillus niger for the purpose of improved citric acid production from cocoyam starch.

  10. Abscisic Acid Stimulates Elongation of Excised Pea Root Tips

    Science.gov (United States)

    Gaither, Douglas H.; Lutz, Donald H.; Forrence, Leonard E.

    1975-01-01

    Excised Pisum sativum L. root tips were incubated in a pH 5.2 sucrose medium containing abscisic acid. Elongation growth was inhibited by 100 μm abscisic acid. However, decreasing the abscisic acid concentration caused stimulation of elongation, the maximum response (25% to 30%) occurring at 1 μm abscisic acid. Prior to two hours, stimulation of elongation by 1 μm abscisic acid was not detectable. Increased elongation did not occur in abscisic acid-treated root tips of Lens culinaris L., Phaseolus vulgaris L., or Zea mays L. PMID:16659198

  11. Omega-3 and Omega-6 Fatty Acids Act as Inhibitors of the Matrix Metalloproteinase-2 and Matrix Metalloproteinase-9 Activity.

    Science.gov (United States)

    Nicolai, Eleonora; Sinibaldi, Federica; Sannino, Gianpaolo; Laganà, Giuseppina; Basoli, Francesco; Licoccia, Silvia; Cozza, Paola; Santucci, Roberto; Piro, Maria Cristina

    2017-08-01

    Polyunsaturated fatty acids have been reported to play a protective role in a wide range of diseases characterized by an increased metalloproteinases (MMPs) activity. The recent finding that omega-3 and omega-6 fatty acids exert an anti-inflammatory effect in periodontal diseases has stimulated the present study, designed to determine whether such properties derive from a direct inhibitory action of these compounds on the activity of MMPs. To this issue, we investigated the effect exerted by omega-3 and omega-6 fatty acids on the activity of MMP-2 and MMP-9, two enzymes that actively participate to the destruction of the organic matrix of dentin following demineralization operated by bacteria acids. Data obtained (both in vitro and on ex-vivo teeth) reveal that omega-3 and omega-6 fatty acids inhibit the proteolytic activity of MMP-2 and MMP-9, two enzymes present in dentin. This observation is of interest since it assigns to these compounds a key role as MMPs inhibitors, and stimulates further study to better define their therapeutic potentialities in carious decay.

  12. Evidence of nonvagal neural stimulation of canine gastric acid secretion.

    Science.gov (United States)

    Tansy, M F; Probst, S J; Martin, J S

    1975-06-01

    In this study, we confirmed our original findings that central vagus stimulation is significantly associated with a subsequent increase in gastric mucus secretion. Central vagus stimulation following phenoxybenzamine hydrochloride administration was associated significantly with protracted elevations in secretory volume and titratable acid. We were unable to conclude that phenoxybenzamine itself in several pharmacologic dosages was associated with an increase in titratable acid. The acid secretory responses could be abolished by transection of the splanchnic nerves. Electrical stimulation of the peripheral part of the splanchnic nerve following administration of phenoxybenzamine was also associated with significant increases in secretory volume and titrable acidity. These secretory responses were not blocked by atropine but were diminished by burimamide. It is concluded that, in the dog, a largely heretofore unsuspected second neural pathway exists which is capable of influencing gastric acid secretion.

  13. Chenodeoxycholic acid stimulated fibroblast growth factor 19 response

    DEFF Research Database (Denmark)

    Borup, C; Wildt, S; Rumessen, J J

    2017-01-01

    BACKGROUND: Bile acid diarrhoea is underdiagnosed and better diagnostic tests are needed. Fasting serum fibroblast growth factor-19 (FGF19) has insufficient diagnostic value, but this may be improved by stimulation. AIM: To explore if an impaired FGF19 response identifies primary bile acid...

  14. Acid rain stimulation of Lake Michigan phytoplankton growth

    Science.gov (United States)

    Manny, Bruce A.; Fahnenstiel, G.L.; Gardner, W.S.

    1987-01-01

    Three laboratory experiments demonstrated that additions of rainwater to epilimnetic lake water collected in southeastern Lake Michigan stimulated chlorophyll a production more than did additions of reagent-grade water during incubations of 12 to 20 d. Chlorophyll a production did not begin until 3–5 d after the rain and lake water were mixed. The stimulation caused by additions of rain acidified to pH 3.0 was greater than that caused by additions of untreated rain (pH 4.0–4.5). Our results support the following hypotheses: (1) Acid rain stimulates the growth of phytoplankton in lake water; (2) phosphorus in rain appears to be the factor causing this stimulation. We conclude that acid rain may accelerate the growth of epilimnetic phytoplankton in Lake Michigan (and other similar lakes) during stratification when other sources of bioavailable phosphorus to the epilimnion are limited

  15. Application of citric acid in acid stimulation treatments

    Energy Technology Data Exchange (ETDEWEB)

    Alkhaldi, M.H.; Sarma, H.K. [Adelaide Univ., Adelaide (Australia); Nasr-el-Din, H.A. [Texas A and M Univ., College Station, TX (United States)

    2009-07-01

    A rotating disk apparatus was used to investigate mass transfer during the reaction of citric acid with calcite. The study evaluated the effects of initial acid concentrations, temperature, and disk rotational speed on the effective diffusion coefficient of citric acid. The diffusion coefficient was calculated at 25, 40, and 50 degrees C using various citric acid concentrations. The study indicated that the coefficient was a function of the interactions between calcium citrate precipitation and counter calcium ions. At high acid concentrations, the effects of calcium citrate precipitation and counter calcium ions were significant. The calculated citric acid diffusion coefficients were not comparable with measured effective diffusion coefficients using the rotating disk. At lower initial citric acid concentrations, the effects of both calcium citrate precipitation and counter calcium ions on citric acid diffusivity were minimal. It was concluded that temperature effects on the diffusion coefficient followed Arrhenius law. Activation energy was equal to 37.9 kJ/mol. 34 refs., 4 tabs., 13 figs.

  16. gamma-Aminobutyric acid stimulates ethylene biosynthesis in sunflower

    International Nuclear Information System (INIS)

    Kathiresan, A.; Tung, P.; Chinnappa, C.C.; Reid, D.M.

    1997-01-01

    gamma-Aminobutyric acid (GABA), a nonprotein amino acid, is often accumulated in plants following environmental stimuli that can also cause ethylene production. We have investigated the relationship between GABA and ethylene production in excised sunflower (Helianthus annuus L.) tissues. Exogenous GABA causes up to a 14-fold increase in the ethylene production rate after about 12 h. Cotyledons fed with [14C]GABA did not release substantial amounts of radioactive ethylene despite its chemical similarity to 1-aminocyclopropane-1-carboxylic acid (ACC), indicating that GABA is not likely to be an alternative precursor for ethylene. GABA causes increases in ACC synthase mRNA accumulation, ACC levels, ACC oxidase mRNA levels, and in vitro ACC oxidase activity. In the presence of aminoethoxyvinylglycine or alpha-aminoisobutyric acid, GABA did not stimulate ethylene production. We therefore conclude that GABA stimulates ethylene biosynthesis mainly by promoting ACC synthase transcript abundance. Possible roles of GABA as a signal transducer are suggested

  17. Adrenergic influence on pentagastrin and bethanechol stimulated gastric acid secretion in dogs with gastric fistula

    DEFF Research Database (Denmark)

    Hovendal, C; Bech, K; Gottrup, F

    1984-01-01

    . The inhibitory effect of isoprenaline on pentagastrin stimulated acid secretion showed the characteristics of competitive type and on bethanechol stimulated acid secretion of non competitive type. An increasing and dose-dependent stimulation of bethanechol stimulated gastric acid secretion was found for dopamine...

  18. Metabolic inhibitors as stimulating factors for citric acid production

    International Nuclear Information System (INIS)

    Adham, N.Z.; Ahmed, E.M.; Refai, H.A.E.

    2008-01-01

    The effect of some metabolic inhibitors on citric acid (CA) production by Aspergillus niger in cane molasses medium was investigated. Addition of 0.01-0.1 mM iodoacetic acid and sodium arsenate, 0.05-1.0 mM sodium malonate, 0.01 mM sodium azide, 0.01-0.05 mM sodium fluoride, 0.1-1.0 mM EDTA stimulated CA production (5-49%). Higher concentrations (10 mM) of iodoacetic acid, sodium malonate and 0.5 mM sodium azide caused a complete inhibition of fungal growth, Iodoacetic acid, sodium arsenate and sodium fluoride (0.2 mM) caused a remarkable inhibition of CA production. The implications of those preliminary functions was discussed. (author)

  19. Stimulation of epithelial cell matrix metalloproteinase (MMP-2, -9, -13) and interleukin-8 secretion by fusobacteria.

    Science.gov (United States)

    Gursoy, U K; Könönen, E; Uitto, V-J

    2008-10-01

    Bacterial pathogens involved in periodontal diseases exert their destructive effects primarily by stimulating the host cells to increase their secretion of proinflammatory cytokines and matrix metalloproteinases (MMPs). This study aimed to determine the epithelial cell matrix metalloproteinase and interleukin-8 (IL-8) secretion upon exposure to fusobacteria. Eight different oral and non-oral Fusobacterium strains were incubated with HaCaT epithelial cells. Gelatin zymography and Western blot analysis were performed to detect collagenase 3 (MMP-13), gelatinase A (MMP-2), gelatinase B (MMP-9), and IL-8 secretion by epithelial cells. All Fusobacterium strains, especially Fusobacterium necrophorum ATCC 25286, Fusobacterium nucleatum ATCC 25586, and Fusobacterium varium ATCC 51644, increased MMP-9 and MMP-13 secretion. Fusobacterium simiae ATCC 33568, and to a lesser extent F. nucleatum and F. necrophorum, increased epithelial MMP-2 secretion. F. nucleatum and F. necrophorum also increased IL-8 secretion. F. varium ATCC 27725, a strain that only weakly stimulated MMP production, strongly increased the IL-8 production, suggesting that their expression is differently regulated. We conclude that the pathogenic potential of fusobacteria may partly result from their ability to stimulate secretion of MMP-9, MMP-13, and IL-8 from epithelial cells.

  20. Stimulated Light Emission in Dense Fog Confined inside a Porous Glass Matrix

    Science.gov (United States)

    Gross, E.; Kovalev, D.; Künzner, N.; Diener, J.; Koch, F.; Fujii, M.

    2002-12-01

    We report on light amplification through stimulated emission in a dielectrically disordered medium. Liquid fragments confined in the solid matrix of porous quartz layers result in a random fluctuation of the dielectric function, and dye molecules embedded in the voids yield optical gain. The level of opacity is tunable by the ambient vapor pressure of the dielectric substance. In the multiple scattering regime, a strong intensity enhancement of the dye emission accompanied by significant spectral narrowing is observed above the threshold for a layer being in the opalescence state.

  1. Iron Oxide Nanoparticles Stimulates Extra-Cellular Matrix Production in Cellular Spheroids

    Directory of Open Access Journals (Sweden)

    Megan Casco

    2017-01-01

    Full Text Available Nanotechnologies have been integrated into drug delivery, and non-invasive imaging applications, into nanostructured scaffolds for the manipulation of cells. The objective of this work was to determine how the physico-chemical properties of magnetic nanoparticles (MNPs and their spatial distribution into cellular spheroids stimulated cells to produce an extracellular matrix (ECM. The MNP concentration (0.03 mg/mL, 0.1 mg/mL and 0.3 mg/mL, type (magnetoferritin, shape (nanorod—85 nm × 425 nm and incorporation method were studied to determine each of their effects on the specific stimulation of four ECM proteins (collagen I, collagen IV, elastin and fibronectin in primary rat aortic smooth muscle cell. Results demonstrated that as MNP concentration increased there was up to a 6.32-fold increase in collagen production over no MNP samples. Semi-quantitative Immunohistochemistry (IHC results demonstrated that MNP type had the greatest influence on elastin production with a 56.28% positive area stain compared to controls and MNP shape favored elastin stimulation with a 50.19% positive area stain. Finally, there are no adverse effects of MNPs on cellular contractile ability. This study provides insight on the stimulation of ECM production in cells and tissues, which is important because it plays a critical role in regulating cellular functions.

  2. Arachidonic acid metabolism in silica-stimulated bovine alveolar macrophages

    International Nuclear Information System (INIS)

    Englen, M.D.

    1989-01-01

    The in vitro production of arachidonic acid (AA) metabolites in adherent bovine alveolar macrophages (BAM) incubated with silica was investigated. BAM were pre-labelled with 3 H-AA, and lipid metabolites released into the culture medium were analyzed by high performance liquid chromatography (HPLC). Lactate dehydrogenase (LDH) release was simultaneously assayed to provide an indication of cell injury. Increasing doses of silica selectively stimulated the 5-lipoxygenase pathway of AA metabolism, while cyclooxygenase metabolite output was suppressed. LDH release increased in a linear, dose-dependent fashion over the range of silica doses used. Moreover, within 15 min following addition of a high silica dose, a shift to the production of 5-lipoxygenase metabolites occurred, accompanied by a reduction in cyclooxygenase products. This rapid alteration in AA metabolism preceded cell injury. To examine the relationship between cytotoxicity and AA metabolite release by BAM exposed to silicas with different cytotoxic and fibrogenic activities, BAM were exposed to different doses of DQ-12, Minusil-5, and Sigma silicas, and carbonyl iron beads. The median effective dose (ED 50 ) of each particulate to stimulate the release of AA metabolites and LDH was calculated. The ED 50 values for DQ-12, Minusil-5, and Sigma silica showed that the relative cytotoxicities of the different silicas for BAM corresponded to the relative potencies of the silicas to elicit 5-lipoxygenase metabolites from BAM. These results indicate that the cytotoxic, and presumed fibrogenic potential, of a silica is correlated with the potency to stimulate the release of leukotrienes from AM

  3. Electric field stimulation through a substrate influences Schwann cell and extracellular matrix structure

    Science.gov (United States)

    Nguyen, Hieu T.; Wei, Claudia; Chow, Jacqueline K.; Nguy, Lindsey; Nguyen, Hieu K.; Schmidt, Christine E.

    2013-08-01

    Objective. Electric field (EF) stimulation has been used to cue cell growth for tissue engineering applications. In this study, we explore the electrical parameters and extracellular mechanisms that elicit changes in cell behavior when stimulated through the substrate. Approach. Rat Schwann cell morphology was compared when exposed to EF through the media or a conductive indium tin oxide substrate. Ionic and structural effects were then analyzed on Matrigel and collagen I, respectively. Main results. When stimulating through media, cells had greater alignment perpendicular to the EF with higher current densities (106 mA cm-2 at 245 mV mm-1), and reached maximum alignment within 8 h. Stimulation through the substrate with EF (up to 110 mV mm-1) did not affect Schwann cell orientation, however the EF caused extracellular matrix (ECM) coatings on substrates to peel away, suggesting EF can physically change the ECM. Applying alternating current (ac) 2-1000 Hz signals through the media or substrate both caused cells to flatten and protrude many processes, without preferential alignment. Matrigel exposed to a substrate EF of 10 mV mm-1 for 2 h had a greater calcium concentration near the cathode, but quickly dissipated when the EF was removed. Schwann cells seeded 7 d after gels were exposed to substrate EF still aligned perpendicular to the EF direction. Microscopy of collagen I exposed to substrate EF shows alignment and bundling of fibrils. Significance. These findings demonstrate EF exposure can control Schwann cell alignment and morphology, change ECM bulk/surface architecture, and align ECM structures.

  4. Corrosion behavior of corrosion resistant alloys in stimulation acids

    Energy Technology Data Exchange (ETDEWEB)

    Cheldi, Tiziana [ENI E and P Division, 20097 San Donato Milanese Milano (Italy); Piccolo, Eugenio Lo; Scoppio, Lucrezia [Centro Sviluppo Materiali, via Castel Romano 100, 00128 Rome (Italy)

    2004-07-01

    In the oil and gas industry, selection of CRAs for downhole tubulars is generally based on resistance to corrosive species in the production environment containing CO{sub 2}, H{sub 2}S, chloride and in some case elemental sulphur. However, there are non-production environments to which these materials must also be resistant for either short term or prolonged duration; these environments include stimulation acids, brine and completion fluids. This paper reports the main results of a laboratory study performed to evaluate the corrosion and stress corrosion behaviour to the acidizing treatments of the most used CRAs for production tubing and casing. Laboratory tests were performed to simulate both 'active' and 'spent' acids operative phases, selecting various environmental conditions. The selected steel pipes were a low alloyed steel, martensitic, super-martensitic, duplex 22 Cr, superduplex 25 Cr and super-austenitic stainless steels (25 Cr 35 Ni). Results obtained in the 'active' acid environments over the temperature range of 100-140 deg. C, showed that the blend acids with HCl at high concentration and HCl + HF represented too much severe conditions, where preventing high general corrosion and heavy localised corrosion by inhibition package becomes very difficult, especially for duplex steel pipe, where, in some case, the specimens were completely dissolved into the solution. On the contrary, all steels pipes were successfully protected by inhibitor when organic acid solution (HCOOH + CH{sub 3}COOH) were used. Furthermore, different effectiveness on corrosion protection was showed by the tested inhibitors packages: e.g. in the 90% HCl at 12% + 10 CH{sub 3}COOH acid blend. In 'spent' acid environments, all steel pipes showed to be less susceptible to the localised and general corrosion attack. Moreover, no Sulphide Stress Corrosion Cracking (SSC) was observed. Only one super-austenitic stainless steel U-bend specimen showed

  5. Relative contribution of matrix metalloprotease and cysteine protease activities to cytokine-stimulated articular cartilage degradation

    DEFF Research Database (Denmark)

    Sondergaard, B C; Henriksen, K; Wulf, H

    2006-01-01

    OBJECTIVE: Both matrix metalloprotease (MMP) activity and cathepsin K (CK) activity have been implicated in cartilage turnover. We investigated the relative contribution of MMP activity and CK activity in cartilage degradation using ex vivo and in vivo models. METHODS: Bovine articular cartilage...... explants were stimulated with oncostatin M (OSM) 10 ng/ml and tumor necrosis factor-alpha (TNF-alpha) 20 ng/ml in the presence or absence of the broad-spectrum MMP inhibitor GM6001 and the cysteine protease inhibitor, E64. Cartilage degradation was evaluated in the conditioned medium by glycosaminoglycans...... was measured from CK-deficient mice. RESULTS: OSM and TNF-alpha combined induced significant (Pcartilage degradation products measured by hydroxyproline and CTX-II compared to vehicle control. The cytokines potently induced MMP expression, assessed by zymography, and CK expression...

  6. Inhibition of food stimulated acid secretion by misoprostol, an orally active synthetic E1 analogue prostaglandin.

    OpenAIRE

    Ramage, J K; Denton, A; Williams, J G

    1985-01-01

    The effect of 200 micrograms misoprostol (a synthetic prostaglandin E1 analogue) on food stimulated intragastric acidity has been monitored over a 9 h period in 16 normal volunteers. Misoprostol caused a significant inhibition of intragastric acidity for 2 h post-dosing, but no significant effect was seen thereafter on either basal or food stimulated acidity.

  7. Hypergravity Stimulates the Extracellular Matrix/Integrin-Signaling Axis and Proliferation in Primary Osteoblasts

    Science.gov (United States)

    Parra, M.; Vercoutere, W.; Roden, C.; Banerjee, I.; Krauser, W.; Holton, E.; Searby, N.; Globus, R.; Almeida, E.

    2003-01-01

    We set out to determine the molecular mechanisms involved in the proliferative response of primary rat osteoblasts to mechanical stimulation using cell culture centrifugation as a model for hypergravity. We hypothesized that this proliferative response is mediated by specific integrin/Extracellular Matrix (ECM) interactions. To investigate this question we developed a cell culture centrifuge and an automated system that performs cell fixation during hypergravity loading. We generated expression vectors for various focal adhesion and cytoskeletal proteins fused to GFP or dsRed and visualized these structures in transfected (or infected) osteoblasts. The actin cytoskeleton was also visualized using rhodamine-phalloidin staining and Focal Adhesion Kinase (FAK) levels were assessed biochemically. We observed that a 24 hour exposure to 50-g stimulated proliferation compared to the 1-g control when cells were plated on fibronectin, collagen Type I , and collagen Type IV, but not on uncoated tissue culture plastic surfaces. This proliferative response was greatest for osteoblasts grown on fibronectin (2-fold increase over 1-g control) and collagen Type I (1.4 fold increase over 1-g control), suggesting that specific matrices and integrins are involved in the signaling pathways required for proliferation. Exposing osteoblasts grown on different matrices to 10-g or 25-g showed that effects on proliferation depended on both matrix type and loading level. We found that osteoblasts exposed to a short pulse of hypergravity during adhesion spread further and had more GFP-FAK containing focal adhesions compared to their 1-g controls. While overall levels of FAK did not change, more FAK was in the active (phosphorylated) form under hypergravity than in the 1-g controls. Cytoskeletal F-actin organization into filaments was also more prominent after brief exposures to hypergravity during the first five minutes of adhesion. These results suggest that specific integrins sense

  8. Science of Hyaluronic Acid Beyond Filling: Fibroblasts and Their Response to the Extracellular Matrix.

    Science.gov (United States)

    Landau, Marina; Fagien, Steven

    2015-11-01

    Loss of viscoelasticity is one of the primarily signs of skin aging, followed by appearance of visible wrinkles. Hyaluronic acid (HA)-based fillers are widely used to fill wrinkles and compensate for volume loss. Recent clinical observations demonstrate persistence of the filling effect longer than the biological availability of the filler. Stimulation of new collagen by cross-linked HA and up-regulation of elastin have been suggested as possible explanation to this observation and have been supported experimentally. Cross-linked HA substitutes for fragmented collagen in restoring extracellular matrix required for normal activity of fibroblasts, such as collagen and elastin production. To restore extracellular matrix efficiently, serial monthly treatments are required. Boosting of facial and nonfacial skin through fibroblast activation is a new indication for HA-based products. Injectable HA has also been recently registered in Europe as agents specific for the improvement of skin quality (Restylane Skinboosters). Further explanation of the possible mechanisms supported by long-term clinical examples is presented herein.

  9. Perfluorooctanoic acid stimulated mitochondrial biogenesis and gene transcription in rats

    International Nuclear Information System (INIS)

    Walters, M.W.; Bjork, J.A.; Wallace, K.B.

    2009-01-01

    Perfluorooctanoic acid (PFOA), used in the production of non-stick surface compounds, exhibits a worldwide distribution in the serum of humans and wildlife. In rodents PFOA transactivates PPARα and PPARγ nuclear receptors and increases mitochondrial DNA (mtDNA) copy number, which may be critical to the altered metabolic state of affected animals. A key regulator of mitochondrial biogenesis and transcription of mitochondrial genes is the PPARγ coactivator-1α (Pgc-1α) protein. The purpose of this study was to determine if Pgc-1α is implicated in the stimulation of mitochondrial biogenesis that occurs following the treatment of rats with PFOA. Livers from adult male Sprague-Dawley rats that received a 30 mg/kg daily oral dose of PFOA for 28 days were used for all experiments. Analysis of mitochondrial replication and transcription was performed by real time PCR, and proteins were detected using western blotting. PFOA treatment caused a transcriptional activation of the mitochondrial biogenesis pathway leading to a doubling of mtDNA copy number. Further, transcription of OXPHOS genes encoded by mtDNA was 3-4 times greater than that of nuclear encoded genes, suggestive of a preferential induction of mtDNA transcription. Western blot analysis revealed an increase in Pgc-1α, unchanged Tfam and decreased Cox II and Cox IV subunit protein expression. We conclude that PFOA treatment in rats induces mitochondrial biogenesis at the transcriptional level with a preferential stimulation of mtDNA transcription and that this occurs by way of activation of the Pgc-1α pathway. Implication of the Pgc-1α pathway is consistent with PPARγ transactivation by PFOA and reveals new understanding and possibly new critical targets for assessing or averting the associated metabolic disease.

  10. The human metapneumovirus matrix protein stimulates the inflammatory immune response in vitro.

    Directory of Open Access Journals (Sweden)

    Audrey Bagnaud-Baule

    Full Text Available Each year, during winter months, human Metapneumovirus (hMPV is associated with epidemics of bronchiolitis resulting in the hospitalization of many infants. Bronchiolitis is an acute illness of the lower respiratory tract with a consequent inflammation of the bronchioles. The rapid onset of inflammation suggests the innate immune response may have a role to play in the pathogenesis of this hMPV infection. Since, the matrix protein is one of the most abundant proteins in the Paramyxoviridae family virion, we hypothesized that the inflammatory modulation observed in hMPV infected patients may be partly associated with the matrix protein (M-hMPV response. By western blot analysis, we detected a soluble form of M-hMPV released from hMPV infected cell as well as from M-hMPV transfected HEK 293T cells suggesting that M-hMPV may be directly in contact with antigen presenting cells (APCs during the course of infection. Moreover, flow cytometry and confocal microscopy allowed determining that M-hMPV was taken up by dendritic cells (moDCs and macrophages inducing their activation. Furthermore, these moDCs enter into a maturation process inducing the secretion of a broad range of inflammatory cytokines when exposed to M-hMPV. Additionally, M-hMPV activated DCs were shown to stimulate IL-2 and IFN-γ production by allogeneic T lymphocytes. This M-hMPV-mediated activation and antigen presentation of APCs may in part explain the marked inflammatory immune response observed in pathology induced by hMPV in patients.

  11. Lysophosphatidic acid stimulates thrombomodulin lectin-like domain shedding in human endothelial cells

    International Nuclear Information System (INIS)

    Wu Hualin; Lin ChiIou; Huang Yuanli; Chen, Pin-Shern; Kuo, Cheng-Hsiang; Chen, Mei-Shing; Wu, G.C.-C.; Shi, G.-Y.; Yang, H.-Y.; Lee Hsinyu

    2008-01-01

    Thrombomodulin (TM) is an anticoagulant glycoprotein highly expressed on endothelial cell surfaces. Increased levels of soluble TM in circulation have been widely accepted as an indicator of endothelial damage or dysfunction. Previous studies indicated that various proinflammatory factors stimulate TM shedding in various cell types such as smooth muscle cells and epithelial cells. Lysophosphatidic acid (LPA) is a bioactive lipid mediator present in biological fluids during endothelial damage or injury. In the present study, we first observed that LPA triggered TM shedding in human umbilical vein endothelial cells (HUVECs). By Cyflow analysis, we showed that the LPA-induced accessibility of antibodies to the endothelial growth factor (EGF)-like domain of TM is independent of matrix metalloproteinases (MMPs), while LPA-induced TM lectin-like domain shedding is MMP-dependent. Furthermore, a stable cell line expressing TM without its lectin-like domain exhibited a higher cell proliferation rate than a stable cell line expressing full-length TM. These results imply that LPA induces TM lectin-like domain shedding, which might contribute to the exposure of its EGF-like domain for EGF receptor (EGFR) binding, thereby stimulating subsequent cell proliferation. Based on our findings, we propose a novel mechanism for the exposure of TM EGF-like domain, which possibly mediates LPA-induced EGFR transactivation

  12. Effects of omega-3 fatty acids on progestin stimulation of invasive properties in breast cancer.

    Science.gov (United States)

    Moore, Michael R; King, Rebecca A

    2012-12-01

    Clinical studies have shown that progestins increase breast cancer risk in hormone replacement therapy, while we and others have previously reported that progestins stimulate invasive properties in progesterone receptor (PR)-rich human breast cancer cell lines. Based on others' reports that omega-3 fatty acids inhibit metastatic properties of breast cancer, we have reviewed the literature for possible connections between omega-3 fatty-acid-driven pathways and progestin-stimulated pathways in an attempt to suggest theoretical mechanisms for possible omega-3 fatty acid inhibition of progestin stimulation of breast cancer invasion. We also present some data suggesting that fatty acids regulate progestin stimulation of invasive properties in PR-rich T47D human breast cancer cells, and that an appropriate concentration of the omega-3 fatty acid eicosapentaenoic acid inhibits progestin stimulation of invasive properties. It is hoped that focus on the inter-relationship between pathways by which omega-3 fatty acids inhibit and progestins stimulate breast cancer invasive properties will lead to further in vitro, in vivo, and clinical studies testing the hypothesis that omega-3 fatty acids can inhibit progestin stimulation of invasive properties in breast cancer, and ameliorate harmful effects of progestins which occur in combined progestin-estrogen hormone replacement therapy.

  13. Pro-inflammatory stimulation of meniscus cells increases production of matrix metalloproteinases and additional catabolic factors involved in osteoarthritis pathogenesis

    Science.gov (United States)

    Stone, Austin V.; Loeser, Richard F.; Vanderman, Kadie S.; Long, David L.; Clark, Stephanie C.; Ferguson, Cristin M.

    2014-01-01

    Objective Meniscus injury increases the risk of osteoarthritis; however, the biologic mechanism remains unknown. We hypothesized that pro-inflammatory stimulation of meniscus would increase production of matrix-degrading enzymes, cytokines and chemokines which cause joint tissue destruction and could contribute to osteoarthritis development. Design Meniscus and cartilage tissue from healthy tissue donors and total knee arthroplasties was cultured. Primary cell cultures were stimulated with pro-inflammatory factors [IL-1β, IL-6, or fibronectin fragments (FnF)] and cellular responses were analyzed by real-time PCR, protein arrays and immunoblots. To determine if NF-κB was required for MMP production, meniscus cultures were treated with inflammatory factors with and without the NF-κB inhibitor, hypoestoxide. Results Normal and osteoarthritic meniscus cells increased their MMP secretion in response to stimulation, but specific patterns emerged that were unique to each stimulus with the greatest number of MMPs expressed in response to FnF. Meniscus collagen and connective tissue growth factor gene expression was reduced. Expression of cytokines (IL-1α, IL-1β, IL-6), chemokines (IL-8, CXCL1, CXCL2, CSF1) and components of the NF-κB and tumor necrosis factor (TNF) family were significantly increased. Cytokine and chemokine protein production was also increased by stimulation. When primary cell cultures were treated with hypoestoxide in conjunction with pro-inflammatory stimulation, p65 activation was reduced as were MMP-1 and MMP-3 production. Conclusions Pro-inflammatory stimulation of meniscus cells increased matrix metalloproteinase production and catabolic gene expression. The meniscus could have an active biologic role in osteoarthritis development following joint injury through increased production of cytokines, chemokines, and matrix-degrading enzymes. PMID:24315792

  14. Identification of Catechin, Syringic Acid, and Procyanidin B2 in Wine as Stimulants of Gastric Acid Secretion.

    Science.gov (United States)

    Liszt, Kathrin Ingrid; Eder, Reinhard; Wendelin, Sylvia; Somoza, Veronika

    2015-09-09

    Organic acids of wine, in addition to ethanol, have been identified as stimulants of gastric acid secretion. This study characterized the influence of other wine compounds, particularly phenolic compounds, on proton secretion. Forty wine parameters were determined in four red wines and six white wines, including the contents of organic acids and phenolic compounds. The secretory activity of the wines was determined in a gastric cell culture model (HGT-1 cells) by means of a pH-sensitive fluorescent dye. Red wines stimulated proton secretion more than white wines. Lactic acid and the phenolic compounds syringic acid, catechin, and procyanidin B2 stimulated proton secretion and correlated with the pro-secretory effect of the wines. Addition of the phenolic compounds to the least active white wine sample enhanced its proton secretory effect by 65 ± 21% (p astringent tasting phenolic compounds in wine contribute to its stimulatory effect on gastric acid secretion.

  15. Regeneration of an aqueous solution from an acid gas absorption process by matrix stripping

    Science.gov (United States)

    Rochelle, Gary T [Austin, TX; Oyenekan, Babatunde A [Katy, TX

    2011-03-08

    Carbon dioxide and other acid gases are removed from gaseous streams using aqueous absorption and stripping processes. By replacing the conventional stripper used to regenerate the aqueous solvent and capture the acid gas with a matrix stripping configuration, less energy is consumed. The matrix stripping configuration uses two or more reboiled strippers at different pressures. The rich feed from the absorption equipment is split among the strippers, and partially regenerated solvent from the highest pressure stripper flows to the middle of sequentially lower pressure strippers in a "matrix" pattern. By selecting certain parameters of the matrix stripping configuration such that the total energy required by the strippers to achieve a desired percentage of acid gas removal from the gaseous stream is minimized, further energy savings can be realized.

  16. Arginine-vasopressin stimulates the formation of phosphatidic acid in rat Leydig cells

    DEFF Research Database (Denmark)

    Nielsen, J.R.; Hansen, Harald S.; Jensen, B.

    1987-01-01

    Arginine-vasopressin (AVP) stimulated the formation of labelled phosphatidic acid (PA) in [C]arachidonic acid-prelabelled rat Leydig cells. After addition of 10 M AVP [C]arachidonoylphosphatidic acid reached a maximum within 2 min. The increase was dose-dependent (10-10 M). No change in labelling...

  17. Matrix metalloproteases as maestros for the dual role of LPS- and IL-10-stimulated macrophages in cancer cell behaviour

    International Nuclear Information System (INIS)

    Cardoso, Ana P.; Pinto, Marta L.; Pinto, Ana T.; Pinto, Marta T.; Monteiro, Cátia; Oliveira, Marta I.; Santos, Susana G.; Relvas, João B.; Seruca, Raquel; Mantovani, Alberto; Mareel, Marc; Barbosa, Mário A.; Oliveira, Maria J.

    2015-01-01

    The interactions established between macrophages and cancer cells are largely dependent on instructions from the tumour microenvironment. Macrophages may differentiate into populations with distinct inflammatory profiles, but knowledge on their role on cancer cell activities is still very scarce. In this work, we investigated the influence of pro-inflammatory (LPS-stimulated) and anti-inflammatory (IL-10-stimulated) macrophages on gastric and colorectal cancer cell invasion, motility/migration, angiogenesis and proteolysis, and the associated molecular mechanisms. Following exposure of gastric and colon cancer cell lines to LPS- and IL-10-stimulated human macrophages, either by indirect contact or conditioned media, we analyzed the effect of the different macrophage populations on cancer cell invasion, migration, motility and phosphorylation status of EGFR and several interacting partners. Cancer-cell induced angiogenesis upon the influence of conditioned media from both macrophage populations was assessed using the chick embryo chorioallantoic membrane assay. MMP activities were evaluated by gelatin zymograhy. Our results show that IL-10-stimulated macrophages are more efficient in promoting in vitro cancer cell invasion and migration. In addition, soluble factors produced by these macrophages enhanced in vivo cancer cell-induced angiogenesis, as opposed to their LPS-stimulated counterparts. We further demonstrate that differences in the ability of these macrophage populations to stimulate invasion or angiogenesis cannot be explained by the EGFR-mediated signalling, since both LPS- and IL-10-stimulated macrophages similarly induce the phosphorylation of cancer cell EGFR, c-Src, Akt, ERK1/2, and p38. Interestingly, both populations exert distinct proteolytic activities, being the IL-10-stimulated macrophages the most efficient in inducing matrix metalloprotease (MMP)-2 and MMP-9 activities. Using a broad-spectrum MMP inhibitor, we demonstrated that proteolysis was

  18. Stimulation of gluconeogenesis by intravenous lipids in preterm infants: response depends on fatty acid profile

    NARCIS (Netherlands)

    van Kempen, Anne A. M. W.; van der Crabben, Saskia N.; Ackermans, Mariëtte T.; Endert, Erik; Kok, Joke H.; Sauerwein, Hans P.

    2006-01-01

    In preterm infants, both hypo- and hyperglycemia are a frequent problem. Intravenous lipids can affect glucose metabolism by stimulation of gluconeogenesis by providing glycerol, which is a gluconeogenic precursor, and/or free fatty acids (FFA), which are stimulants of the rate of gluconeogenesis.

  19. Early increase of amino acid transport in stimulated lymphocytes

    NARCIS (Netherlands)

    Berg, K.J. van den; Betel, I.

    1971-01-01

    Chemicals/CAS: 2 amino 2 methylpropionic acid, 62-57-7; carbon, 7440-44-0; thymidine, 50-89-5; tritium, 10028-17-8; Aminoisobutyric Acids; Carbon Isotopes; Lectins; Thymidine, 50-89-5; Tritium, 10028-17-8

  20. EMMPRIN mediates beta-adrenergic receptor-stimulated matrix metalloproteinase activity in cardiac myocytes.

    OpenAIRE

    Siwik Deborah A; Kuster Gabriela M; Brahmbhatt Jamin V; Zaidi Zaheer; Malik Julia; Ooi Henry; Ghorayeb Ghassan

    2008-01-01

    Extracellular matrix metalloproteinase inducer (EMMPRIN) expression is increased in myocardium from patients with dilated cardiomyopathy and animal models of heart failure. However little is known about the regulated expression or functional role of EMMPRIN in the myocardium. In rat cardiac cells EMMPRIN is expressed on myocytes but not endothelial cells or fibroblasts. Therefore we tested the hypothesis that EMMPRIN expression regulates matrix metalloproteinase (MMP) activity in rat ventricu...

  1. Clofibric acid stimulates branched-chain amino acid catabolism by three mechanisms.

    Science.gov (United States)

    Kobayashi, Rumi; Murakami, Taro; Obayashi, Mariko; Nakai, Naoya; Jaskiewicz, Jerzy; Fujiwara, Yoko; Shimomura, Yoshiharu; Harris, Robert A

    2002-11-15

    Clofibrate promotes catabolism of branched-chain amino acids by increasing the activity of the branched-chain alpha-keto acid dehydrogenase [BCKDH] complex. Depending upon the sex of the rats, nutritional state, and tissue being studied, clofibrate can affect BCKDH complex activity by three different mechanisms. First, by directly inhibiting BCKDH kinase activity, clofibrate can increase the proportion of the BCKDH complex in the active, dephosphorylated state. This occurs in situations in which the BCKDH complex is largely inactive due to phosphorylation, e.g., in the skeletal muscle of chow-fed rats or in the liver of female rats late in the light cycle. Second, by increasing the levels at which the enzyme components of the BCKDH complex are expressed, clofibrate can increase the total enzymatic activity of the BCKDH complex. This is readily demonstrated in livers of rats fed a low-protein diet, a nutritional condition that induces a decrease in the level of expression of the BCKDH complex. Third, by decreasing the amount of BCKDH kinase expressed and therefore its activity, clofibrate induces an increase in the percentage of the BCKDH complex in the active, dephosphorylated state. This occurs in the livers of rats fed a low-protein diet, a nutritional condition that causes inactivation of the BCKDH complex due to upregulation of the amount of BCKDH kinase. WY-14,643, which, like clofibric acid, is a ligand for the peroxisome-proliferator-activated receptor alpha [PPARalpha], does not directly inhibit BCKDH kinase but produces the same long-term effects as clofibrate on expression of the BCKDH complex and its kinase. Thus, clofibrate is unique in its capacity to stimulate BCAA oxidation through inhibition of BCKDH kinase activity, whereas PPARalpha activators in general promote BCAA oxidation by increasing expression of components of the BCKDH complex and decreasing expression of the BCKDH kinase.

  2. Okadaic Acid, a Bioactive Fatty Acid from Halichondria okadai, Stimulates Lipolysis in Rat Adipocytes: The Pivotal Role of Perilipin Translocation

    Directory of Open Access Journals (Sweden)

    Nen-Chung Chang

    2013-01-01

    Full Text Available Lipid metabolism in visceral fat cells is correlated with metabolic syndrome and cardiovascular diseases. Okadaic-acid, a 38-carbon fatty acid isolated from the black sponge Halichondria okadai, can stimulate lipolysis by promoting the phosphorylation of several proteins in adipocytes. However, the mechanism of okadaic acid-induced lipolysis and the effects of okadaic acid on lipid-droplet-associated proteins (perilipins and beta-actin remain unclear. We isolated adipocytes from rat epididymal fat pads and treated them with isoproterenol and/or okadaic acid to estimate lipolysis by measuring glycerol release. Incubating adipocytes with okadaic acid stimulated time-dependent lipolysis. Lipid-droplet-associated perilipins and beta-actin were analyzed by immunoblotting and immunofluorescence, and the association of perilipin A and B was found to be decreased in response to isoproterenol or okadaic acid treatment. Moreover, okadaic-acid treatment could enhance isoproterenol-mediated lipolysis, whereas treatment of several inhibitors such as KT-5720 (PKA inhibitor, calphostin C (PKC inhibitor, or KT-5823 (PKG inhibitor did not attenuate okadaic-acid-induced lipolysis. By contrast, vanadyl acetylacetonate (tyrosine phosphatase inhibitor blocked okadaic-acid-dependent lipolysis. These results suggest that okadaic acid induces the phosphorylation and detachment of lipid-droplet-associated perilipin A and B from the lipid droplet surface and thereby leads to accelerated lipolysis.

  3. Lysophosphatidic acid (LPA) effects on endometrial carcinoma in vitro proliferation, invasion, and matrix metalloproteinase activity.

    Science.gov (United States)

    Wang, Feng-qiang; Ariztia, Edgardo V; Boyd, Leslie R; Horton, Faith R; Smicun, Yoel; Hetherington, Jessica A; Smith, Phillip J; Fishman, David A

    2010-04-01

    Lysophosphatidic acid (LPA) has potent growth-regulatory effect in many cell types and has been linked to the in vivo tumor growth and metastasis in several malignancies. The goal of this study was to assess the regulation of (EC) microenvironment by LPA through the examination of its effect on cell proliferation, migration, invasion, uPA activity, and matrix metalloproteinase (MMP) secretion/activation. All experiments were performed in vitro using an EC cell line, HEC-1A. Cell proliferation was determined using the Promega MTS proliferation assay following 48 h of exposures to different concentrations of LPA (0.1, 1.0 and 10.0 microM). Cell invasion was assessed using a modified Boyden chamber assay with collagen I coated on the membrane. HEC-1A motility was examined by Boyden chamber migration assay as well as the scratch wound closure assay on type I collagen. MMP secretion/activation in HEC-1A conditioned medium was detected by gelatin zymography. MMP-7 mRNA expression was determined using real-time PCR. uPA activity was measured using a coupled colorimetric assay. LPA, at the concentrations of 0.1 and 1.0 microM, significantly induced the proliferation of HEC-1A cells (p0.05). Gelatin zymogram showed that HEC-1A cells secreted high levels of MMP-7, while MMP-2 and MMP-9 are barely detectable. In addition, LPA significantly enhanced uPA activity in HEC-1A conditioned medium in a concentration-dependent manner. LPA is a potent modulator of cellular proliferation and invasion for EC cells. It also has the capacity to stimulate the secretion/activity of uPA and MMP-7. Those results suggest that LPA is a bioactive modulator of EC microenvironment and may have a distinct regulation mechanism as observed in epithelial ovarian cancer. Copyright 2009. Published by Elsevier Inc.

  4. Stimulation of Lactic Acid Bacteria by a Micrococcus Isolate: Evidence for Multiple Effects

    Science.gov (United States)

    Nath, K. R.; Wagner, B. J.

    1973-01-01

    Growth of, and rate of acid production by, six cultures of lactic acid bacteria were increased in the presence of Micrococcus isolate F4 or a preparation of its capsular material. Concentrations of hydrogen peroxide found in pure cultures of the lactic acid bacteria were not detectable, or were greatly reduced, in mixed culture with Micrococcus isolate F4. The capsular material was not as effective as whole cells in preventing accumulation of H2O2. Catalase stimulated growth of, and the rate of acid production by, the lactic acid bacteria, but not to the same extent as Micrococcus isolate F4 in some cultures. The existence of two mechanisms for micrococcal stimulation of the lactic acid bacteria is postulated. One mechanism involves removal of H2O2; the other has not been characterized. PMID:4199337

  5. 3-Aminoquinoline/p-coumaric acid as a MALDI matrix for glycopeptides, carbohydrates, and phosphopeptides.

    Science.gov (United States)

    Fukuyama, Yuko; Funakoshi, Natsumi; Takeyama, Kohei; Hioki, Yusaku; Nishikaze, Takashi; Kaneshiro, Kaoru; Kawabata, Shin-Ichirou; Iwamoto, Shinichi; Tanaka, Koichi

    2014-02-18

    Glycosylation and phosphorylation are important post-translational modifications in biological processes and biomarker research. The difficulty in analyzing these modifications is mainly their low abundance and dissociation of labile regions such as sialic acids or phosphate groups. One solution in matrix-assisted laser desorption/ionization (MALDI) mass spectrometry is to improve matrices for glycopeptides, carbohydrates, and phosphopeptides by increasing the sensitivity and suppressing dissociation of the labile regions. Recently, a liquid matrix 3-aminoquinoline (3-AQ)/α-cyano-4-hydroxycinnamic acid (CHCA) (3-AQ/CHCA), introduced by Kolli et al. in 1996, has been reported to increase sensitivity for carbohydrates or phosphopeptides, but it has not been systematically evaluated for glycopeptides. In addition, 3-AQ/CHCA enhances the dissociation of labile regions. In contrast, a liquid matrix 1,1,3,3-tetramethylguanidium (TMG, G) salt of p-coumaric acid (CA) (G3CA) was reported to suppress dissociation of sulfate groups or sialic acids of carbohydrates. Here we introduce a liquid matrix 3-AQ/CA for glycopeptides, carbohydrates, and phosphopeptides. All of the analytes were detected as [M + H](+) or [M - H](-) with higher or comparable sensitivity using 3-AQ/CA compared with 3-AQ/CHCA or 2,5-dihydroxybenzoic acid (2,5-DHB). The sensitivity was increased 1- to 1000-fold using 3-AQ/CA. The dissociation of labile regions such as sialic acids or phosphate groups and the fragmentation of neutral carbohydrates were suppressed more using 3-AQ/CA than using 3-AQ/CHCA or 2,5-DHB. 3-AQ/CA was thus determined to be an effective MALDI matrix for high sensitivity and the suppression of dissociation of labile regions in glycosylation and phosphorylation analyses.

  6. Low molecular weight polylactic acid as a matrix for the delayed release of pesticides.

    Science.gov (United States)

    Zhao, Jing; Wilkins, Richard M

    2005-05-18

    Low molecular weight polylactic acid (LMW PLA) was used as a matrix to formulate biodegradable matrix granules and films with bromacil using a melt process. The compatibility of the PLA with bromacil was evaluated. The release characteristics of the formulations were investigated in vitro. The degradation and erosion of the formulations were monitored by pH and gravimetric analysis during the course of release. Various granules and films had similar biphasic release patterns, a delayed release followed by an explosive release. The release rates were independent of bromacil content in the matrix, but varied with the geometry of matrices. The mechanisms of diffusion and erosion were involved in the release. The delayed release of the formulations was dominantly governed by the degradation and erosion of PLA. LMW PLA underwent bulk erosion. LMW PLA-based matrix formulations could thus be useful for the application of pesticides to sensitive targets such as seed treatment.

  7. Chemically modified tetracyclines stimulate matrix metalloproteinase-s production by periodontal ligament cells

    NARCIS (Netherlands)

    Bildt, M.M.; Snoek-van Beurden, A.M.P.; Groot, J. de; El, B. van; Kuijpers-Jagtman, A.M.; Hoff, J.W. van den

    2006-01-01

    Background and Objective: The purpose of this study was to investigate the effects of chemically modified tetracyclines (CMTs) on the production of gelatinases [matrix metalloproteinase (MMP)-2 and -9] by human periodontal ligament (PDL) cells, and on the activity of recombinant gelatinases.

  8. Phosphoric acid as a matrix additive for MALDI MS analysis of phosphopeptides and phosphoproteins

    DEFF Research Database (Denmark)

    Kjellström, Sven; Jensen, Ole Nørregaard

    2004-01-01

    Phosphopeptides are often detected with low efficiency by MALDI MS analysis of peptide mixtures. In an effort to improve the phosphopeptide ion response in MALDI MS, we investigated the effects of adding low concentrations of organic and inorganic acids during peptide sample preparation in 2,5-di...... acid to 2,5-DHB were also observed in LC-MALDI-MS analysis of tryptic phosphopeptides of B. subtilis PrkC phosphoprotein. Finally, the mass resolution of MALDI mass spectra of intact proteins was significantly improved by using phosphoric acid in 2,5-DHB matrix....

  9. Pretreatment with oleic acid accelerates the entrance into the mitotic cycle of EGF-stimulated fibroblasts.

    Science.gov (United States)

    Zugaza, J L; Casabiell, X A; Bokser, L; Eiras, A; Beiras, A; Casanueva, F F

    1995-07-01

    We have previously demonstrated that pretreatment of several cell lines with cis-unsaturated fatty acids, like oleic acid, blocks epidermal growth factor (EGF)-induced early ionic signals, and in particular the [Ca2+]i rise. In the present work we show that this blockade does not alter EGF-stimulated cellular proliferation evaluated by direct cell counting, but induces a powerful enhancement in the pulsed thymidine incorporation assay. The lack of effect of oleic acid on EGF-stimulated cellular proliferation was confirmed by repeated cell counts, cumulative thymidine incorporation, and protein synthesis, but a clear synergistic effect between oleic acid and EGF was again obtained by means of time course experiments with pulsed thymidine. Combined flow cytometry analysis and cell counts at earlier times in EGF-stimulated cells showed that oleic acids accelerates the entrance of cells into the replicative cycle leading to an earlier cell division. Afterward, these oleic acid-pretreated cells became delayed by an unknown compensatory mechanism in such a way that at 48 h post-EGF, the cell count in control and oleic acid-pretreated cells was equal. In conclusion (a) oleic acid accelerates or enhances the EGF mitogenic action and (b) in the long term cells compensate the initial perturbation with respect to untreated cells. As a side observation, the widely employed pulsed thymidine incorporation method as a measure of cell division could be extremely misleading unless experimental conditions are well controlled.

  10. Glucose-stimulated acrolein production from unsaturated fatty acids.

    Science.gov (United States)

    Medina-Navarro, R; Duran-Reyes, G; Diaz-Flores, M; Hicks, J J; Kumate, J

    2004-02-01

    Glucose auto-oxidation may be a significant source of reactive oxygen species (ROS), and also be important in the lipid peroxidation process, accompanied by the release of toxic reactive products. We wanted to demonstrate that acrolein can be formed directly and actively from free fatty acids in a hyperglycemic environment. A suspension of linoleic and arachidonic acids (2.5 mM) was exposed to different glucose concentrations (5, 10 and 15 mmol/L) in vitro. The samples were extracted with organic solvents, partitioned, followed at 255-267 nm, and analysed using capillary electrophoresis and mass spectroscopy. The total release of aldehydes significantly (P products, acrolein (5% of total) and its condensing product, 4-hydroxy-hexenal, were identified. From the results presented here, it was possible to demonstrate the production of acrolein, probably as a fatty acid product, due to free radicals generated from the glucose auto-oxidation process. The results led us to propose that acrolein, which is one of the most toxic aldehydes, is produced during hyperglycemic states, and may lead to tissue injury, as one of the initial problems to be linked to high levels of glucose in vivo.

  11. Activation of PPARd and RXRa stimulates fatty acid oxidatin and insulin secretion inpancreatic beta-cells

    DEFF Research Database (Denmark)

    Børgesen, Michael; Ravnskjær, Kim; Frigerio, Francesca

    as a central effector of unsaturated fatty acids in pancreatic ß-cells. Interestingly, activation of PPARd increases basal as well as glucose-stimulated insulin secretion of INS-1E cells. This increase is further potentiated by RXR agonists. This observation suggests that PPARd may mediate some of the positive......ACTIVATION OF PPARd AND RXRa STIMULATES FATTY ACID OXIDATION AND INSULIN SECRETION IN PANCREATIC b-CELLS Michael Boergesen1, Kim Ravnskjaer2, Francesca Frigerio3, Allan E. Karlsen4, Pierre Maechler3 and Susanne Mandrup1 1 Department of Biochemistry and Molecular Biology, University of Southern...... of genes as PPARd specific agonists and stimulates ß-oxidation. Importantly, oleate-induction of gene expression and ß-oxidation in INS-1E cells is abolished by knock-down of PPARd using adenoviral transfer of shRNA. Thus, PPARd appears to be a central regulator of fatty acid metabolism as well...

  12. 10-oxo-12(Z)-octadecenoic acid, a linoleic acid metabolite produced by gut lactic acid bacteria, potently activates PPARγ and stimulates adipogenesis.

    Science.gov (United States)

    Goto, Tsuyoshi; Kim, Young-Il; Furuzono, Tomoya; Takahashi, Nobuyuki; Yamakuni, Kanae; Yang, Ha-Eun; Li, Yongjia; Ohue, Ryuji; Nomura, Wataru; Sugawara, Tatsuya; Yu, Rina; Kitamura, Nahoko; Park, Si-Bum; Kishino, Shigenobu; Ogawa, Jun; Kawada, Teruo

    2015-04-17

    Our previous study has shown that gut lactic acid bacteria generate various kinds of fatty acids from polyunsaturated fatty acids such as linoleic acid (LA). In this study, we investigated the effects of LA and LA-derived fatty acids on the activation of peroxisome proliferator-activated receptors (PPARs) which regulate whole-body energy metabolism. None of the fatty acids activated PPARδ, whereas almost all activated PPARα in luciferase assays. Two fatty acids potently activated PPARγ, a master regulator of adipocyte differentiation, with 10-oxo-12(Z)-octadecenoic acid (KetoA) having the most potency. In 3T3-L1 cells, KetoA induced adipocyte differentiation via the activation of PPARγ, and increased adiponectin production and insulin-stimulated glucose uptake. These findings suggest that fatty acids, including KetoA, generated in gut by lactic acid bacteria may be involved in the regulation of host energy metabolism. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Ureaplasma isolates stimulate pro-inflammatory CC chemokines and matrix metalloproteinase-9 in neonatal and adult monocytes

    Science.gov (United States)

    Silwedel, Christine; Fehrholz, Markus; Henrich, Birgit; Waaga-Gasser, Ana Maria; Claus, Heike; Speer, Christian P.

    2018-01-01

    Being generally regarded as commensal bacteria, the pro-inflammatory capacity of Ureaplasma species has long been debated. Recently, we confirmed Ureaplasma–driven pro-inflammatory cytokine responses and a disturbance of cytokine equilibrium in primary human monocytes in vitro. The present study addressed the expression of CC chemokines and matrix metalloproteinase-9 (MMP-9) in purified term neonatal and adult monocytes stimulated with serovar 8 of Ureaplasma urealyticum (Uu) and serovar 3 of U. parvum (Up). Using qRT-PCR and multi-analyte immunoassay, we assessed mRNA and protein expression of the monocyte chemotactic proteins 1 and 3 (MCP-1/3), the macrophage inflammatory proteins 1α and 1β (MIP-1α/β) as well as MMP-9. For the most part, both isolates stimulated mRNA expression of all given chemokines and MMP-9 in cord blood and adult monocytes (pUreaplasma isolates in vitro, adding to our previous data. Findings from co-stimulated cells indicate that Ureaplasma may modulate monocyte immune responses to a second stimulus. PMID:29558521

  14. Stimulation of matrix formation in rabbit chondrocyte cultures by ascorbate. 1. Effect of ascorbate analogs and beta-aminopropionitrile.

    Science.gov (United States)

    Wright, G C; Wei, X Q; McDevitt, C A; Lane, B P; Sokoloff, L

    1988-01-01

    The most consistent effects of 0.2 mM L-ascorbate on monolayer cultures of rabbit articular chondrocytes were a diversion of incorporated radiosulfate into a pericellular matrix and enhancement of cell proliferation. Only with certain batches of fetal bovine serum (FBS) was there a cell-for-cell increase of proteoglycan synthesis. These actions increased as the cell inoculum rose from 0.5 to 2 x 10(5) cells/T25 flask. Maximal effects of ascorbate and D-isoascorbate were found over a range of 0.05-0.2 mM. L-Dehydroascorbic acid was less effective than either, and no stimulatory action was exerted by L-cysteine, glutathione, dithiothreitol, methylene blue, or phenazine methosulfate. Ascorbate increased the hypro:pro ratio of newly synthesized proteins. beta-Aminopropionitrile (1 mM) reduced the proportion of [3H]hydroxyproline and [35S]O4-proteoglycans in the ascorbate-supplemented matrix 31 and 7%, respectively. In corresponding electronmicrographs, the number of pericellular filaments was reduced. We conclude: (a) Ascorbate has a general anabolic effect on chondrocytes in culture and enhances matrix assembly through mechanisms other than its redox function; (b) deposition of proteoglycans in the matrix is not simply the result of mechanical entrapment by allysine- or hydroxyallysine-derived cross-linking of collagen; and (c) contradictory reports on the subject result from variations in the serum employed, inoculum density, and concentration of ascorbate.

  15. Stimulation of apical sodium-dependent bile acid transporter expands the bile acid pool and generates bile acids with positive feedback properties.

    Science.gov (United States)

    Rudling, Mats; Bonde, Ylva

    2015-01-01

    Bile acid synthesis has been considered a prototype for how a physiological process is controlled by end product feedback inhibition. By this feedback inhibition, bile acid concentrations are kept within safe ranges. However, careful examination of published rodent data strongly suggests that bile acid synthesis is also under potent positive feedback control by hydrophilic bile acids. Current concepts on the regulation of bile acid synthesis are derived from mouse models. Recent data have shown that mice have farnesoid X receptor (FXR) antagonistic bile acids capable of quenching responses elicited by FXR agonistic bile acids. This is important to recognize to understand the regulation of bile acid synthesis in the mouse, and in particular to clarify if mouse model findings are valid also in the human situation. In addition to classic end product feedback inhibition, regulation of bile acid synthesis in the mouse largely appears also to be driven by changes in hepatic levels of murine bile acids such as α- and β-muricholic acids. This has not been previously recognized. Stimulated bile acid synthesis or induction of the apical sodium-dependent bile acid transporter in the intestine, increase the availability of chenodeoxycholic acid in the liver, thereby promoting hepatic conversion of this bile acid into muricholic acids. Recognition of these mechanisms is essential for understanding the regulation of bile acid synthesis in the mouse, and for our awareness of important species differences in the regulation of bile acid synthesis in mice and humans. 2015 S. Karger AG, Basel.

  16. Acetaldehyde stimulation of net gluconeogenic carbon movement from applied malic acid in tomato fruit pericarp tissue

    International Nuclear Information System (INIS)

    Halinska, A.; Frenkel, C.

    1991-01-01

    Applied acetaldehyde is known to lead to sugar accumulation in fruit including tomatoes (Lycopersicon esculentum) presumably due to stimulation of gluconeogenesis. This conjecture was examined using tomato fruit pericarp discs as a test system and applied l-[U- 14 C]malic acid as the source for gluconeogenic carbon mobilization. Results indicate that malic and perhaps other organic acids are carbon sources for gluconeogenesis occurring normally in ripening tomatoes. The process is stimulated by acetaldehyde apparently by attenuating the fructose-2,6-biphosphate levels. The mode of the acetaldehyde regulation of fructose-2,6-biphosphate metabolism awaits clarification

  17. Ultraviolet radiation stimulates the release of arachidonic acid from mammalian cells in culture

    International Nuclear Information System (INIS)

    De Leo, V.A.; Hanson, D.; Weinstein, I.B.; Harber, L.C.

    1985-01-01

    C3H 10T1/2 cells in culture were prelabelled with [ 3 H]arachidonic acid and exposed to UVB radiation. Almost immediately after irradiation cells released labelled arachidonate metabolites into media in a dose dependent manner. This release was inhibited by removing calcium ions from the system and by the addition of dexamethasone and parabromophenacyl bromide to the system. This suggests that the UVB stimulated release of arachidonic acid from membrane phospholipids is, in part, mediated by a phospholipase A 2 enzyme system. Thin layer chromatographic examination of media extracts revealed a dose dependent UVB stimulation of prostaglandin production by cultured cells. (author)

  18. Role of stimulated amino acid transport in promoting glycogenesis in the irradiated rat

    International Nuclear Information System (INIS)

    Kilberg, M.S.; Neuhaus, O.W.

    1976-01-01

    Whole-body irradiation of rats stimulates an amino acid transport system in the liver. Another phenomenon observed after exposure to ionizing radiations is the accumulation of hepatic glycogen. The data presented here relate the increased hepatic uptake of amino acids to glycogenesis. Male rats were exposed to two doses of γ rays, 2500 and 1500 R. Following exposure to 2500 R, the hepatic free amino acids were elevated during the first 48 hr accompanied by a decline in serum levels. At 72 hr the hepatic amino acids diminished to the control levels while the serum increased abruptly. By contrast, 72 hr after exposure to 1500 R the serum amino acid levels increased only 27 percent and the hepatic amino acid values increased 52 percent. These results are explained on the basis of the changes in AIB transport previously reported. The incorporation of 14 C from labeled L-alanine into hepatic glycogen was maximal 48 hr postexposure to 2500 R but declined to below control values at 72 hr. On the other hand, exposure to 1500 R resulted in maximal incorporation of 14 C at both 48 and 72 hr. We propose that transport of amino acids into liver cells is stimulated by the elevated blood levels of amino acids released from the degradation of protein. The transport increases the levels of hepatic free amino acids, and therefore, is a key factor in regulating postirradiation glycogenesis

  19. The Development of Reproducible and Selective Uric Acid Biosensor by Using Electrodeposited Polytyramine as Matrix Polymer

    Directory of Open Access Journals (Sweden)

    Manihar Situmorang

    2017-11-01

    Full Text Available A versatile method for the construction of reproducible and high selective uric acid biosensor is explained. Electrodeposited polytyramine is used as biosensor matrixes due to its compatibility to immobilize enzyme uric oxidase in the membrane electrode. The precise control over the charge passed during deposition of polytyramine allows concomitant control over the thickness of the deposited enzyme layers onto the surface of the electrode. The uric acid biosensor showed a sensitive response to uric acid with a linear calibration curve lies in the concentration range of 0.1–2.5 mM, slope 0.066 µA mM-1, and the limit detection was 0.01 mM uric acid (S/N = 3. The biosensor shown excellent reproducibility, the variation between response curves for uric acid lies between RSD 1% at low concentrations and up to RSD 6% at saturation concentration. Uric acid biosensor is free from normal interference. The biosensor showed good stability and to be applicable to determine uric acid in real samples. Analysis of uric acid in the reference standard serum samples by the biosensor method are all agreed with the real value from supplier. Standard samples were also analyzed independently by two methods: the present biosensor method and the standard UV-Vis spectrophotometry method, gave a correlation coefficient of 0.994. This result confirms that the biosensor method meets the rigid demands expected for uric acid in real samples.

  20. Relative turnover of [3H]arachidonic acid and [14C]eicosapentaenoic acid in stimulated human platelets

    International Nuclear Information System (INIS)

    Weaver, B.J.; Holub, B.J.

    1986-01-01

    The relative release of arachidonic acid (AA) versus eicosapentaenoic acid (EPA) from platelet phospholipids may be important in accounting for the potential of dietary fish oil containing EPA to alter platelet reactivity. Human platelets enriched in EPA and prelabelled with [ 3 H]AA and [ 14 C]EPA were used to examine the relative losses of these fatty acids from platelet phospholipids upon stimulation. Washed dual-labelled platelets were incubated with and without thrombin in the presence of BW755C and in the presence and absence of trifluoperazine. The platelet lipids were extracted and the individual phospholipids as well as diacylglycerol (DG), phosphatidic acid (PA), etc. were separated by thin-layer chromatography and the radioactivity in each fraction determined. The [ 3 H]AA/[ 14 C]EPA dpm ratio for the loss in radioactivity from PC upon thrombin stimulation was similar to that for the PC in resting platelets. This suggests no marked selectivity in the degradation of AA versus EPA species of PC during platelet activation. The [ 3 H]/[ 14 C] ratios for the increased radioactivity in DG and PA upon thrombin stimulation were slightly higher than the ratio in PI from resting platelets suggesting only a minor preference for 1-acyl 2-arachidonoyl PI over 1-acyl 2-eicosapentaenoyl PI in the pathway from PI to DG to PA

  1. Preconception folic acid use modulates estradiol and follicular responses to ovarian stimulation.

    Science.gov (United States)

    Twigt, John M; Hammiche, Fatima; Sinclair, Kevin D; Beckers, Nicole G; Visser, Jenny A; Lindemans, Jan; de Jong, Frank H; Laven, Joop S E; Steegers-Theunissen, Régine P

    2011-02-01

    Folate is a methyl donor. Availability of folate affects DNA methylation profiles and thereby gene expression profiles. We investigated the effects of low-dose folic acid use (0.4 mg/d) on the ovarian response to mild and conventional ovarian stimulation in women. In a randomized trial among subfertile women, 24 and 26 subjects received conventional and mild ovarian stimulation, respectively. Blood samples were taken during the early follicular phase of the cycle prior to treatment and on the day of human chorionic gonadotropin administration for determination of serum total homocysteine, anti-Müllerian hormone (AMH), estradiol, and folate. Folic acid use was validated by questionnaire and serum folate levels. Preovulatory follicles were visualized, counted, and diameters recorded using transvaginal ultrasound. The relation between folic acid use and ovarian response was assessed using linear regression analysis. Folic acid use modified the ovarian response to ovarian stimulation treatment. The estradiol response was higher in nonfolic acid users receiving conventional treatment [β(interaction) = 0.52 (0.07-0.97); P = 0.03], and this effect was independent of serum AMH levels and the preovulatory follicle count. In the conventional treatment, the mean follicle number was also greater in nonusers compared with the users group (14.1 vs. 8.9, P = 0.03). Low-dose folic acid use attenuates follicular and endocrine responses to conventional stimulation, independent of AMH and follicle count. The nature of this observation suggests that the effect of folic acid is most prominent during early follicle development, affecting immature follicles. Deleterious effects of folate deficiency, like DNA hypomethylation and oxidative stress, can help to explain our observations.

  2. Effect of esophageal distention on basal and stimulated gastric acid secretion in rats

    Directory of Open Access Journals (Sweden)

    Mohammad Kazem Gharib Nasery

    2007-02-01

    Full Text Available Background: It is well established that the esophageal distention leads to gastric relaxation, partly by vago-vagal reflex but till now, the effect of esophageal distention on gastric acid secretion has not been investigated. The aim of this study was to investigate the effect of esophageal distention (ED on basal and stimulated gastric acid secretion. Methods: Adult male Wistar rats (200-240g were deprived of food but not water for 24 hrs before the experiments. Under urethane anesthesia (1.2 g/kg, i.p., animals underwent tracheostomy and laparotomy. A catheter was inserted in the stomach through duodenum for gastric distention and gastric washout and the esophagus was cannulated with a distensible balloon orally to distend esophagus (0.3 ml, 10 min. Gastric acid secretion was stimulated by gastric distention, carbachol (4 µg/kg, i.p. or histamine (5 mg/kg, s.c.. Effects of vagotomy, L-NAME (10 mg/kg, i.v., L-arginine (500 mg/kg, i.p. and hexamethonium were also investigated. Results: Esophageal distention reduces basal and gastric distention, carbachol and histamine stimulated acid secretion (P<0.05, P<0.0001, P<0.01 and P<0.02, respectively. Vagotomy reduced the inhibitory effect of the esophagus distention on gastric distention-induced acid secretion (P<0.05. Conclusion: These results indicate that vagus nerve involves in the inhibitory effect of the esophageal distention on the basal and stimulated gastric acid secretion. Nitric oxide (NO may also be involved.

  3. Excitatory amino acid-stimulated uptake of 22Na+ in primary astrocyte cultures

    International Nuclear Information System (INIS)

    Kimelberg, H.K.; Pang, S.; Treble, D.H.

    1989-01-01

    In this study we have found that L-glutamic acid, as well as being taken up by a Na+-dependent mechanism, will stimulate the uptake of 22Na+ by primary astrocyte cultures from rat brain in the presence of ouabain. By simultaneously measuring the uptake of 22Na+ and L-3H-glutamate a stoichiometry of 2-3 Na+ per glutamate was measured, implying electrogenic uptake. Increasing the medium K+ concentration to depolarize the cells inhibited L-3H-glutamate uptake, while calculations of the energetics of the observed L-3H-glutamate accumulation also supported an electrogenic mechanism of at least 2 Na+:1 glutamate. In contrast, kinetic analysis of the Na+ dependence of L-3H-glutamate uptake indicated a stoichiometry of Na+ to glutamate of 1:1, but further analysis showed that the stoichiometry cannot be resolved by purely kinetic studies. Studies with glutamate analogs, however, showed that kainic acid was a very effective stimulant of 22Na+ uptake, but 3H-kainic acid showed no Na+ -dependent uptake. Furthermore, while L-3H-glutamate uptake was very sensitive to lowered temperatures, glutamate-stimulated 22Na+ uptake was relatively insensitive. These results indicate that glutamate-stimulated uptake of 22Na+ in primary astrocytes cultures cannot be explained solely by cotransport of Na+ with glutamate, and they suggest that direct kainic acid-type receptor induced stimulation of Na+ uptake also occurs. Since both receptor and uptake effects involve transport of Na+, accurate measurements of the Na+ :glutamate stoichiometry for uptake can only be done using completely specific inhibitors of these 2 systems

  4. 10-oxo-12(Z)-octadecenoic acid, a linoleic acid metabolite produced by gut lactic acid bacteria, potently activates PPARγ and stimulates adipogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Goto, Tsuyoshi, E-mail: tgoto@kais.kyoto-u.ac.jp [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji 611-0011 (Japan); Research Unit for Physiological Chemistry, The Center for the Promotion of Interdisciplinary Education and Research, Kyoto University (Japan); Kim, Young-Il; Furuzono, Tomoya [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji 611-0011 (Japan); Takahashi, Nobuyuki [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji 611-0011 (Japan); Research Unit for Physiological Chemistry, The Center for the Promotion of Interdisciplinary Education and Research, Kyoto University (Japan); Yamakuni, Kanae; Yang, Ha-Eun; Li, Yongjia [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji 611-0011 (Japan); Ohue, Ryuji [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji 611-0011 (Japan); Research Unit for Physiological Chemistry, The Center for the Promotion of Interdisciplinary Education and Research, Kyoto University (Japan); Nomura, Wataru [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji 611-0011 (Japan); Sugawara, Tatsuya [Laboratory of Marine Bioproducts Technology, Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502 (Japan); Yu, Rina [Department of Food Science and Nutrition, University of Ulsan, Ulsan 680-749 (Korea, Republic of); Kitamura, Nahoko [Laboratory of Fermentation Physiology and Applied Microbiology, Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502 (Japan); and others

    2015-04-17

    Our previous study has shown that gut lactic acid bacteria generate various kinds of fatty acids from polyunsaturated fatty acids such as linoleic acid (LA). In this study, we investigated the effects of LA and LA-derived fatty acids on the activation of peroxisome proliferator-activated receptors (PPARs) which regulate whole-body energy metabolism. None of the fatty acids activated PPARδ, whereas almost all activated PPARα in luciferase assays. Two fatty acids potently activated PPARγ, a master regulator of adipocyte differentiation, with 10-oxo-12(Z)-octadecenoic acid (KetoA) having the most potency. In 3T3-L1 cells, KetoA induced adipocyte differentiation via the activation of PPARγ, and increased adiponectin production and insulin-stimulated glucose uptake. These findings suggest that fatty acids, including KetoA, generated in gut by lactic acid bacteria may be involved in the regulation of host energy metabolism. - Highlights: • Most LA-derived fatty acids from gut lactic acid bacteria potently activated PPARα. • Among tested fatty acids, KetoA and KetoC significantly activated PPARγ. • KetoA induced adipocyte differentiation via the activation of PPARγ. • KetoA enhanced adiponectin production and glucose uptake during adipogenesis.

  5. 10-oxo-12(Z)-octadecenoic acid, a linoleic acid metabolite produced by gut lactic acid bacteria, potently activates PPARγ and stimulates adipogenesis

    International Nuclear Information System (INIS)

    Goto, Tsuyoshi; Kim, Young-Il; Furuzono, Tomoya; Takahashi, Nobuyuki; Yamakuni, Kanae; Yang, Ha-Eun; Li, Yongjia; Ohue, Ryuji; Nomura, Wataru; Sugawara, Tatsuya; Yu, Rina; Kitamura, Nahoko

    2015-01-01

    Our previous study has shown that gut lactic acid bacteria generate various kinds of fatty acids from polyunsaturated fatty acids such as linoleic acid (LA). In this study, we investigated the effects of LA and LA-derived fatty acids on the activation of peroxisome proliferator-activated receptors (PPARs) which regulate whole-body energy metabolism. None of the fatty acids activated PPARδ, whereas almost all activated PPARα in luciferase assays. Two fatty acids potently activated PPARγ, a master regulator of adipocyte differentiation, with 10-oxo-12(Z)-octadecenoic acid (KetoA) having the most potency. In 3T3-L1 cells, KetoA induced adipocyte differentiation via the activation of PPARγ, and increased adiponectin production and insulin-stimulated glucose uptake. These findings suggest that fatty acids, including KetoA, generated in gut by lactic acid bacteria may be involved in the regulation of host energy metabolism. - Highlights: • Most LA-derived fatty acids from gut lactic acid bacteria potently activated PPARα. • Among tested fatty acids, KetoA and KetoC significantly activated PPARγ. • KetoA induced adipocyte differentiation via the activation of PPARγ. • KetoA enhanced adiponectin production and glucose uptake during adipogenesis

  6. The effect of Centella asiatica, vitamins, glycolic acid and their mixtures preparations in stimulating collagen and fibronectin synthesis in cultured human skin fibroblast.

    Science.gov (United States)

    Hashim, Puziah

    2014-03-01

    Centella asiatica (Linn.) Urban is well known in promoting wound healing and provides significant benefits in skin care and therapeutic products formulation. Glycolic acid and vitamins also play a role in the enhancement of collagen and fibronectin synthesis. Here, we evaluate the specific effect of Centella asiatica (CA), vitamins, glycolic acid and their mixture preparations to stimulate collagen and fibronectin synthesis in cultured human fibroblast cells. The fibroblast cells are incubated with CA, glycolic acid, vitamins and their mixture preparations for 48 h. The cell lysates were analyzed for protein content and collagen synthesis by direct binding enzyme immunoassay. The fibronectin of the cultured supernatant was measured by sandwich enzyme immunoassay. The results showed that CA, glycolic acid, vitamins A, E and C significantly stimulate collagen and fibronectin synthesis in the fibroblast. Addition of glycolic acid and vitamins to CA further increased the levels of collagen and fibronectin synthesis to 8.55 and 23.75 μg/100 μg, respectively. CA, glycolic acid, vitamins A, E, and C, and their mixtures demonstrated stimulatory effect on both extra-cellular matrix synthesis of collagen and fibronectin in in vitro studies on human foreskin fibroblasts, which is beneficial to skin care and therapeutic products formulation.

  7. A novel enzyme-based acidizing system: Matrix acidizing and drilling fluid damage removal

    Energy Technology Data Exchange (ETDEWEB)

    Harris, R.E.; McKay, D.M. [Cleansorb Limited, Surrey (United Kingdom); Moses, V. [King`s College, London (United Kingdom)

    1995-12-31

    A novel acidizing process is used to increase the permeability of carbonate rock cores in the laboratory and to remove drilling fluid damage from cores and wafers. Field results show the benefits of the technology as applied both to injector and producer wells.

  8. Stimulation of deep gas wells using HCl/formic acid system : lab studies and field application

    Energy Technology Data Exchange (ETDEWEB)

    Nasr-El-Din, H.A.; Al-Mutairi, S.; Al-Malki, B. [Saudi Aramco (Saudi Arabia); Metcalf, S.; Walters, W. [BJ Services Co USA, Houston, TX (United States)

    2002-06-01

    Well stimulation in the deep carbonate Khuff reservoirs in eastern Saudi Arabia is needed to remove drilling mud filter cakes and to enhance reservoir permeability. A non associated gas is being produced from the reservoirs. This gas is associated with the hydrogen sulfide content that varies from 0 to 10-mol per cent. The average reservoir temperature is 275 degrees F and initial reservoir pressure is 7,000 psi. A special system is needed to stimulate the carbonate reservoir because of this high bottomhole temperature and the corrosive nature of hydrochloric acid (HCl) at high temperature. A rotating disk method was used to determine the reaction rate of an HCl/formic acid system with reservoir rocks. Results from coreflood tests showed that the acid system creates deep wormholes in tight reservoir cores. Corrosion tests showed that the well tubulars could tolerate the acid system. A gelled 15-wt per cent HCl/9-wt per cent formic acid system successfully fractured 3 vertical wells in deep sour gas reservoirs without any operational problems. The treatment resulted in significant increases in gas production and flowing wellhead pressures. In addition, overflush of the treatment successfully eliminated the return of live acid after the treatment. 37 refs., 10 tabs., 17 figs.

  9. Interleukin-2 stimulates osteoclastic activity: Increased acid production and radioactive calcium release

    International Nuclear Information System (INIS)

    Ries, W.L.; Seeds, M.C.; Key, L.L.

    1989-01-01

    Recombinant human interleukin-2 (IL-2) was studied to determine effects on acid production by individual osteoclasts in situ on mouse calvarial bones. This analysis was performed using a microspectrofluorimetric technique to quantify acid production in individual cells. Radioactive calcium release was determined using calvarial bones in a standard tissue culture system. This allowed us to correlate changes in acid production with a measure of bone resorption. IL-2 stimulated acid production and bone resorbing activity. Both effects were inhibited by calcitonin. No stimulation of bone resorption occurred when IL-2-containing test media was incubated with a specific anti-IL-2 antibody and ultrafiltered. Our data demonstrated a correlation between acid production and bone resorbing activity in mouse calvaria exposed to parathyroid hormone (PTH). The data obtained from cultured mouse calvaria exposed to IL-2 demonstrated similar stimulatory effects to those seen during PTH exposure. These data suggest that calvaria exposed to IL-2 in vitro have increased osteoclastic acid production corresponding with increased bone resorption. (author)

  10. Anti-inflammatory Chitosan/Poly-γ-glutamic acid nanoparticles control inflammation while remodeling extracellular matrix in degenerated intervertebral disc.

    Science.gov (United States)

    Teixeira, Graciosa Q; Leite Pereira, Catarina; Castro, Flávia; Ferreira, Joana R; Gomez-Lazaro, Maria; Aguiar, Paulo; Barbosa, Mário A; Neidlinger-Wilke, Cornelia; Goncalves, Raquel M

    2016-09-15

    Intervertebral disc (IVD) degeneration is one of the most common causes of low back pain (LBP), the leading disorder in terms of years lived with disability. Inflammation can play a role in LPB, while impairs IVD regeneration. In spite of this, different inflammatory targets have been purposed in the context of IVD regeneration. Anti-inflammatory nanoparticles (NPs) of Chitosan and Poly-(γ-glutamic acid) with a non-steroidal anti-inflammatory drug, diclofenac (Df), were previously shown to counteract a pro-inflammatory response of human macrophages. Here, the effect of intradiscal injection of Df-NPs in degenerated IVD was evaluated. For that, Df-NPs were injected in a bovine IVD organ culture in pro-inflammatory/degenerative conditions, upon stimulation with needle-puncture and interleukin (IL)-1β. Df-NPs were internalized by IVD cells, down-regulating IL-6, IL-8, MMP1 and MMP3, and decreasing PGE2 production, compared with IL-1β-stimulated IVD punches. Interestingly, at the same time, Df-NPs promoted an up-regulation of extracellular matrix (ECM) proteins, namely collagen type II and aggrecan. Allover, this study suggests that IVD treatment with Df-NPs not only reduces inflammation, but also delays and/or decreases ECM degradation, opening perspectives to new intradiscal therapies for IVD degeneration, based on the modulation of inflammation. Degeneration of the IVD is an age-related progressive process considered to be the major cause of spine disorders. The pro-inflammatory environment and biomechanics of the degenerated IVD is a challenge for regenerative therapies. The novelty of this work is the intradiscal injection of an anti-inflammatory therapy based on Chitosan (Ch)/Poly-(γ-glutamic acid) (γ-PGA) nanoparticles (NPs) with an anti-inflammatory drug (diclofenac, Df), previously developed by us. This drug delivery system was tested in a pro-inflammatory/degenerative intervertebral disc ex vivo model. The main findings support the success of an anti

  11. Lauric Acid Stimulates Ketone Body Production in the KT-5 Astrocyte Cell Line.

    Science.gov (United States)

    Nonaka, Yudai; Takagi, Tetsuo; Inai, Makoto; Nishimura, Shuhei; Urashima, Shogo; Honda, Kazumitsu; Aoyama, Toshiaki; Terada, Shin

    2016-08-01

    Coconut oil has recently attracted considerable attention as a potential Alzheimer's disease therapy because it contains large amounts of medium-chain fatty acids (MCFAs) and its consumption is thought to stimulate hepatic ketogenesis, supplying an alternative energy source for brains with impaired glucose metabolism. In this study, we first reevaluated the responses of plasma ketone bodies to oral administration of coconut oil to rats. We found that the coconut oil-induced increase in plasma ketone body concentration was negligible and did not significantly differ from that observed after high-oleic sunflower oil administration. In contrast, the administration of coconut oil substantially increased the plasma free fatty acid concentration and lauric acid content, which is the major MCFA in coconut oil. Next, to elucidate whether lauric acid can activate ketogenesis in astrocytes with the capacity to generate ketone bodies from fatty acids, we treated the KT-5 astrocyte cell line with 50 and 100 μM lauric acid for 4 h. The lauric acid treatments increased the total ketone body concentration in the cell culture supernatant to a greater extent than oleic acid, suggesting that lauric acid can directly and potently activate ketogenesis in KT-5 astrocytes. These results suggest that coconut oil intake may improve brain health by directly activating ketogenesis in astrocytes and thereby by providing fuel to neighboring neurons.

  12. Folic Acid supplementation stimulates notch signaling and cell proliferation in embryonic neural stem cells.

    Science.gov (United States)

    Liu, Huan; Huang, Guo-Wei; Zhang, Xu-Mei; Ren, Da-Lin; X Wilson, John

    2010-09-01

    The present study investigated the effect of folic acid supplementation on the Notch signaling pathway and cell proliferation in rat embryonic neural stem cells (NSCs). The NSCs were isolated from E14-16 rat brain and grown as neurospheres in serum-free suspension culture. Individual cultures were assigned to one of 3 treatment groups that differed according to the concentration of folic acid in the medium: Control (baseline folic acid concentration of 4 mg/l), low folic acid supplementation (4 mg/l above baseline, Folate-L) and high folic acid supplementation (40 mg/l above baseline, Folate-H). NSCs were identified by their expression of immunoreactive nestin and proliferating cells by incorporation of 5'bromo-2'deoxyuridine. Cell proliferation was also assessed by methyl thiazolyl tetrazolium assay. Notch signaling was analyzed by real-time PCR and western blot analyses of the expression of Notch1 and hairy and enhancer of split 5 (Hes5). Supplementation of NSCs with folic acid increased the mRNA and protein expression levels of Notch1 and Hes5. Folic acid supplementation also stimulated NSC proliferation dose-dependently. Embryonic NSCs respond to folic acid supplementation with increased Notch signaling and cell proliferation. This mechanism may mediate the effects of folic acid supplementation on neurogenesis in the embryonic nervous system.

  13. Photochemical and radiation-chemical aspects of matrix acidity effects on some organic systems

    Science.gov (United States)

    Ambroz, H. B.; Przybytniak, G. K.; Wronska, T.; Kemp, T. J.

    The role of matrix effects in radiolysis and photolysis is illustrated using two systems: organosulphur compounds and benzenediazonium salts. Their intermediates as detected by low temperature ESR and optical spectroscopy or FAB-MS give evidence that the main reaction pathways depend strongly on these effects. Changes in matrix acidity can control the formation of neutral radical, ion-radical or ionic species which are crucial to the character of the final products of irradiation of organosulphur compounds, which are of great importance in medicine, biology, ecology and industry. Microenvironmental influences determine whether the triplet aryl cation or radical species are detected as the principal or sole intermediates in the decomposition of diazonium salts, a process leading to different stable products with industrial application.

  14. Structure and expression of an unusually acidic matrix protein of pearl oyster shells

    International Nuclear Information System (INIS)

    Tsukamoto, Daiki; Sarashina, Isao; Endo, Kazuyoshi

    2004-01-01

    We report identification and characterization of the unusually acidic molluscan shell matrix protein Aspein, which may have important roles in calcium carbonate biomineralization. The Aspein gene (aspein) encodes a sequence of 413 amino acids, including a high proportion of Asp (60.4%), Gly (16.0%), and Ser (13.2%), and the predicted isoelectric point is 1.45; this is the most acidic of all the molluscan shell matrix proteins sequenced so far, or probably even of all known proteins on earth. The main body of Aspein is occupied by (Asp) 2-10 sequences punctuated with Ser-Gly dipeptides. RT-PCR demonstrated that the transcript of aspein is expressed at the outer edge of the mantle, corresponding to the calcitic prismatic layer, but not at the inner part of the mantle, corresponding to the aragonitic nacreous layer. Our findings and previous in vitro experiments taken together suggest that Aspein is responsible for directed formation of calcite in the shell of the pearl oyster Pinctada fucata

  15. Nitrogenous compounds stimulate glucose-derived acid production by oral Streptococcus and Actinomyces.

    Science.gov (United States)

    Norimatsu, Yuka; Kawashima, Junko; Takano-Yamamoto, Teruko; Takahashi, Nobuhiro

    2015-09-01

    Both Streptococcus and Actinomyces can produce acids from dietary sugars and are frequently found in caries lesions. In the oral cavity, nitrogenous compounds, such as peptides and amino acids, are provided continuously by saliva and crevicular gingival fluid. Given that these bacteria can also utilize nitrogen compounds for their growth, it was hypothesized that nitrogenous compounds may influence their acid production; however, no previous studies have examined this topic. Therefore, the present study aimed to assess the effects of nitrogenous compounds (tryptone and glutamate) on glucose-derived acid production by Streptococcus and Actinomyces. Acid production was evaluated using a pH-stat method under anaerobic conditions, whereas the amounts of metabolic end-products were quantified using high performance liquid chromatography. Tryptone enhanced glucose-derived acid production by up to 2.68-fold, whereas glutamate enhanced Streptococcus species only. However, neither tryptone nor glutamate altered the end-product profiles, indicating that the nitrogenous compounds stimulate the whole metabolic pathways involving in acid production from glucose, but are not actively metabolized, nor do they alter metabolic pathways. These results suggest that nitrogenous compounds in the oral cavity promote acid production by Streptococcus and Actinomyces in vivo. © 2015 The Societies and Wiley Publishing Asia Pty Ltd.

  16. Thyroid hormone reduces PCSK9 and stimulates bile acid synthesis in humans[S

    OpenAIRE

    Bonde, Ylva; Breuer, Olof; L?tjohann, Dieter; Sj?berg, Stefan; Angelin, Bo; Rudling, Mats

    2014-01-01

    Reduced plasma LDL-cholesterol is a hallmark of hyperthyroidism and is caused by transcriptional stimulation of LDL receptors in the liver. Here, we investigated whether thyroid hormone (TH) actions involve other mechanisms that may also account for the reduction in LDL-cholesterol, including effects on proprotein convertase subtilisin/kexin type 9 (PCSK9) and bile acid synthesis. Twenty hyperthyroid patients were studied before and after clinical normalization, and the responses to hyperthyr...

  17. Chlorogenic acids biosynthesis in Centella asiatica cells is not stimulated by salicylic acid manipulation

    CSIR Research Space (South Africa)

    Ncube, EN

    2016-07-01

    Full Text Available Exogenous application of synthetic and natural elicitors of plant defence has been shown to result in mass production of secondary metabolites with nutraceuticals properties in cultured cells. In particular, salicylic acid (SA) treatment has been...

  18. Oleanolic acid acetate inhibits rheumatoid arthritis by modulating T cell immune responses and matrix-degrading enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jin Kyeong [Department of Pharmacology, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of); Molecular Immunology Section, Laboratory of Immunology, National Eye Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Kim, Sung-Wan; Kim, Duk-Sil [Department of Thoracic and Cardiovascular Surgery, CHA Gumi Medical Center, CHA University, Gumi 730-040 (Korea, Republic of); Lee, Jong Yeong [Department of Pharmacology, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of); Lee, Soyoung [Department of Pharmacology, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of); Bio-Materials Research Institute, Korea Research Institute of Bioscience and Biotechnology, Jeongeup 580-185 (Korea, Republic of); Oh, Hyun-Mee [Bio-Materials Research Institute, Korea Research Institute of Bioscience and Biotechnology, Jeongeup 580-185 (Korea, Republic of); Ha, Yeong Su; Yoo, Jeongsoo [Department of Molecular Medicine, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of); Park, Pil-Hoon [College of Pharmacy, Yeungnam University, Gyeongbuk 712-749 (Korea, Republic of); Shin, Tae-Yong [College of Pharmacy, Woosuk University, Jeonju 565-701 (Korea, Republic of); Kwon, Taeg Kyu [Department of Immunology, School of Medicine, Keimyung University, Daegu 704-701 (Korea, Republic of); Rho, Mun-Chual, E-mail: rho-m@kribb.re.kr [Bio-Materials Research Institute, Korea Research Institute of Bioscience and Biotechnology, Jeongeup 580-185 (Korea, Republic of); Kim, Sang-Hyun, E-mail: shkim72@knu.ac.kr [Department of Pharmacology, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of)

    2016-01-01

    ABSTRACT: Rheumatoid arthritis (RA) is a chronic autoimmune disease associated with a combination of synovium joint inflammation, synovium hyperplasia, and destruction of cartilage and bone. Oleanolic acid acetate (OAA), a compound isolated from Vigna angularis, has been known to possess pharmacological activities, including anti-inflammation and anti-bone destruction. In this study, we investigated the effects of OAA on RA and the underlying mechanisms of action by using a type-II collagen-induced arthritis (CIA) mouse model and tumor necrosis factor (TNF)-α-stimulated RA synovial fibroblasts. Oral administration of OAA decreased the clinical arthritis symptoms, paw thickness, histologic and radiologic changes, and serum total and anti-type II collagen IgG, IgG1, and IgG2a levels. OAA administration reduced Th1/Th17 phenotype CD4{sup +} T lymphocyte expansions and inflammatory cytokine productions in T cell activated draining lymph nodes and spleen. OAA reduced the expression and production of inflammatory mediators, such as cytokines and matrix metalloproteinase (MMP)-1/3, in the ankle joint tissue and RA synovial fibroblasts by down-regulating Akt, mitogen-activated protein kinases, and nuclear factor-κB. Our results clearly support that OAA plays a therapeutic role in RA pathogenesis by modulating helper T cell immune responses and matrix-degrading enzymes. The immunosuppressive effects of OAA were comparable to dexamethasone and ketoprofen. We provide evidences that OAA could be a potential therapeutic candidate for RA. - Highlights: • OAA attenuated chronic CIA symptoms. • OAA had a regulating effect on the T helper cell immune reaction for CIA. • The effect of OAA on the RA was comparable to the dexamethasone or ketoprofen. • OAA might be a candidate for the treatment of arthritic diseases.

  19. Demineralised human dentine matrix stimulates the expression of VEGF and accelerates the bone repair in tooth sockets of rats.

    Science.gov (United States)

    Reis-Filho, Cláudio R; Silva, Elisângela R; Martins, Adalberto B; Pessoa, Fernanda F; Gomes, Paula V N; de Araújo, Mariana S C; Miziara, Melissa N; Alves, José B

    2012-05-01

    In this study we investigated the possible use of human demineralised dentine matrix (DHDM), obtained from the extracted teeth, as bone graft material and evaluated the expression of vascular endothelial growth factor (VEGF) induced by this material in the healing process of tooth sockets of rats. To evaluate bone regeneration and expression of VEGF induced by DHDM, thirty-two male Wistar rats weighing approximately 200 g were used. After maxillary second molar extraction, the left sockets were filled with DHDM and the right sockets were naturally filled by blood clot (control). The animals were sacrificed at 3, 7, 14 and 21 days after surgery and upper maxillaries were processed for histological, morphometric and immunohistochemical analyses. DHDM was used to evaluate the mechanical effect of bone graft material into sockets. Expression of VEGF was determined by immunohistochemistry in all groups. Our results demonstrated a significant increase in the newly formed bone tissue in sockets of 7, 14 and 21 days and a significant increase in VEGF expression at days 7 and 14 on treated sockets. Our results showed that DHDM increases the expression of VEGF and accelerates the healing process in rats tooth sockets, by stimulating bone deposition and also vessels formation. These results suggest that DHDM has osteoinductive/osteoconductive potential and may represent an efficient grafting material on guided bone regeneration. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Haloperidol Abrogates Matrix Metalloproteinase-9 Expression by Inhibition of NF-κB Activation in Stimulated Human Monocytic Cells

    Directory of Open Access Journals (Sweden)

    Yueh-Lun Lee

    2018-01-01

    Full Text Available Much evidence has indicated that matrix metalloproteinases (MMPs participate in the progression of neuroinflammatory disorders. The present study was undertaken to investigate the inhibitory effect and mechanism of the antipsychotic haloperidol on MMP activation in the stimulated THP-1 monocytic cells. Haloperidol exerted a strong inhibition on tumor necrosis factor- (TNF- α-induced MMP-9 gelatinolysis of THP-1 cells. A concentration-dependent inhibitory effect of haloperidol was observed in TNF-α-induced protein and mRNA expression of MMP-9. On the other hand, haloperidol slightly affected cell viability and tissue inhibition of metalloproteinase-1 levels. It significantly inhibited the degradation of inhibitor-κB-α (IκBα in activated cells. Moreover, it suppressed activated nuclear factor-κB (NF-κB detected by a mobility shift assay, NF-κB reporter gene, and chromatin immunoprecipitation analyses. Consistent with NF-κB inhibition, haloperidol exerted a strong inhibition of lipopolysaccharide- (LPS- induced MMP-9 gelatinolysis but not of transforming growth factor-β1-induced MMP-2. In in vivo studies, administration of haloperidol significantly attenuated LPS-induced intracerebral MMP-9 activation of the brain homogenate and the in situ in C57BL/6 mice. In conclusion, the selective anti-MMP-9 activation of haloperidol could possibly involve the inhibition of the NF-κB signal pathway. Hence, it was found that haloperidol treatment may represent a bystander of anti-MMP actions for its conventional psychotherapy.

  1. Receptor-mediated uptake of low density lipoprotein stimulates bile acid synthesis by cultured rat hepatocytes

    International Nuclear Information System (INIS)

    Junker, L.H.; Davis, R.A.

    1989-01-01

    The cellular mechanisms responsible for the lipoprotein-mediated stimulation of bile acid synthesis in cultured rat hepatocytes were investigated. Adding 280 micrograms/ml of cholesterol in the form of human or rat low density lipoprotein (LDL) to the culture medium increased bile acid synthesis by 1.8- and 1.6-fold, respectively. As a result of the uptake of LDL, the synthesis of [14C]cholesterol from [2-14C]acetate was decreased and cellular cholesteryl ester mass was increased. Further studies demonstrated that rat apoE-free LDL and apoE-rich high density lipoprotein (HDL) both stimulated bile acid synthesis 1.5-fold, as well as inhibited the formation of [14C]cholesterol from [2-14C]acetate. Reductive methylation of LDL blocked the inhibition of cholesterol synthesis, as well as the stimulation of bile acid synthesis, suggesting that these processes require receptor-mediated uptake. To identify the receptors responsible, competitive binding studies using 125I-labeled apoE-free LDL and 125I-labeled apoE-rich HDL were performed. Both apoE-free LDL and apoE-rich HDL displayed an equal ability to compete for binding of the other, suggesting that a receptor or a group of receptors that recognizes both apolipoproteins is involved. Additional studies show that hepatocytes from cholestyramine-treated rats displayed 2.2- and 3.4-fold increases in the binding of apoE-free LDL and apoE-rich HDL, respectively. These data show for the first time that receptor-mediated uptake of LDL by the liver is intimately linked to processes activating bile acid synthesis

  2. Extracellular DNA and lipoteichoic acids interact with exopolysaccharides in the extracellular matrix of Streptococcus mutans biofilms

    Science.gov (United States)

    Castillo Pedraza, Midian C.; Novais, Tatiana F.; Faustoferri, Roberta C.; Quivey, Robert G.; Terekhov, Anton; Hamaker, Bruce R.; Klein, Marlise I.

    2018-01-01

    Streptococcus mutans -derived exopolysaccharides are virulence determinants in the matrix of biofilms that cause caries. Extracellular DNA (eDNA) and lipoteichoic acid (LTA) are found in cariogenic biofilms, but their functions are unclear. Therefore, strains of S. mutans carrying single deletions that would modulate matrix components were used: eDNA – ΔlytS and ΔlytT; LTA – ΔdltA and ΔdltD; and insoluble exopolysaccharide – ΔgtfB. Single-species (parental strain S. mutans UA159 or individual mutant strains) and mixed-species (UA159 or mutant strain, Actinomyces naeslundii and Streptococcus gordonii) biofilms were evaluated. Distinct amounts of matrix components were detected, depending on the inactivated gene. eDNA was found to be cooperative with exopolysaccharide in early phases, while LTA played a larger role in the later phases of biofilm development. The architecture of mutant strains biofilms was distinct (vs UA159), demonstrating that eDNA and LTA influence exopolysaccharide distribution and microcolony organization. Thus, eDNA and LTA may shape exopolysaccharide structure, affecting strategies for controlling pathogenic biofilms. PMID:28946780

  3. Extracellular DNA and lipoteichoic acids interact with exopolysaccharides in the extracellular matrix of Streptococcus mutans biofilms.

    Science.gov (United States)

    Castillo Pedraza, Midian C; Novais, Tatiana F; Faustoferri, Roberta C; Quivey, Robert G; Terekhov, Anton; Hamaker, Bruce R; Klein, Marlise I

    2017-10-01

    Streptococcus mutans-derived exopolysaccharides are virulence determinants in the matrix of biofilms that cause caries. Extracellular DNA (eDNA) and lipoteichoic acid (LTA) are found in cariogenic biofilms, but their functions are unclear. Therefore, strains of S. mutans carrying single deletions that would modulate matrix components were used: eDNA - ∆lytS and ∆lytT; LTA - ∆dltA and ∆dltD; and insoluble exopolysaccharide - ΔgtfB. Single-species (parental strain S. mutans UA159 or individual mutant strains) and mixed-species (UA159 or mutant strain, Actinomyces naeslundii and Streptococcus gordonii) biofilms were evaluated. Distinct amounts of matrix components were detected, depending on the inactivated gene. eDNA was found to be cooperative with exopolysaccharide in early phases, while LTA played a larger role in the later phases of biofilm development. The architecture of mutant strains biofilms was distinct (vs UA159), demonstrating that eDNA and LTA influence exopolysaccharide distribution and microcolony organization. Thus, eDNA and LTA may shape exopolysaccharide structure, affecting strategies for controlling pathogenic biofilms.

  4. Taurine ameliorates cholesterol metabolism by stimulating bile acid production in high-cholesterol-fed rats.

    Science.gov (United States)

    Murakami, Shigeru; Fujita, Michiko; Nakamura, Masakazu; Sakono, Masanobu; Nishizono, Shoko; Sato, Masao; Imaizumi, Katsumi; Mori, Mari; Fukuda, Nobuhiro

    2016-03-01

    This study was designed to investigate the effects of dietary taurine on cholesterol metabolism in high-cholesterol-fed rats. Male Sprague-Dawley rats were randomly divided into two dietary groups (n = 6 in each group): a high-cholesterol diet containing 0.5% cholesterol and 0.15% sodium cholate, and a high-cholesterol diet with 5% (w/w) taurine. The experimental diets were given for 2 weeks. Taurine supplementation reduced the serum and hepatic cholesterol levels by 37% and 32%, respectively. Faecal excretion of bile acids was significantly increased in taurine-treated rats, compared with untreated rats. Biliary bile acid concentrations were also increased by taurine. Taurine supplementation increased taurine-conjugated bile acids by 61% and decreased glycine-conjugated bile acids by 53%, resulting in a significant decrease in the glycine/taurine (G/T) ratio. Among the taurine-conjugated bile acids, cholic acid and deoxycholic acid were significantly increased. In the liver, taurine supplementation increased the mRNA expression and enzymatic activity of hepatic cholesterol 7α-hydroxylase (CYP7A1), the rate-limiting enzyme for bile acid synthesis, by three- and two-fold, respectively. Taurine also decreased the enzymatic activity of acyl-CoA:cholesterol acyltransferase (ACAT) and microsomal triglyceride transfer protein (MTP). These observations suggest that taurine supplementation increases the synthesis and excretion of taurine-conjugated bile acids and stimulates the catabolism of cholesterol to bile acid by elevating the expression and activity of CYP7A1. This may reduce cholesterol esterification and lipoprotein assembly for very low density lipoprotein (VLDL) secretion, leading to reductions in the serum and hepatic cholesterol levels. © 2016 John Wiley & Sons Australia, Ltd.

  5. The characterisation of molecular boric acid by mass spectrometry and matrix isolation-infrared spectroscopy

    International Nuclear Information System (INIS)

    Ogden, J.S.; Young, N.A.; Bowsher, B.R.

    1987-10-01

    Boric acid (H 3 BO 3 ) is used as a soluble neutron absorber in the coolant of pressurised water reactors and will be an important species in defining the fission product chemistry of severe reactor accidents. Mass spectrometry and matrix isolation-infrared spectroscopy have been used to characterise boric acid in the vapour phase and hence assess the implications of any chemical interactions. Crystalline orthoboric acid vaporises to yield molecular H 3 BO 3 when heated in vacuum to approximately 40 0 C. The infrared spectrum of the vapour species isolated in low-temperature nitrogen matrices shows characteristic absorptions at 3668.5 (E'), 1426.2 (E'), 1009.9 (E'), 675.0 (A''), 513.8 (A'') and 448.9 (E') cm -1 , consistent with C 3h symmetry. These spectral assignments are supported by extensive isotope labelling, and by a partial normal co-ordinate analysis. These data will be used to quantify specific thermodynamic functions and hence assist in determining the magnitude of reactions such as boric acid with caesium iodide. (author)

  6. Extracellular matrix assembly in extreme acidic eukaryotic biofilms and their possible implications in heavy metal adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Aguilera, Angeles [Centro de Astrobiologia (INTA-CSIC), Carretera de Ajalvir Km 4, Torrejon de Ardoz, 28850 Madrid (Spain)], E-mail: aguileraba@inta.es; Souza-Egipsy, Virginia [Centro de Astrobiologia (INTA-CSIC), Carretera de Ajalvir Km 4, Torrejon de Ardoz, 28850 Madrid (Spain); San Martin-Uriz, Patxi [Centro de Biologia Molecular (UAM-CSIC), Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain); Amils, Ricardo [Centro de Astrobiologia (INTA-CSIC), Carretera de Ajalvir Km 4, Torrejon de Ardoz, 28850 Madrid (Spain); Centro de Biologia Molecular (UAM-CSIC), Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain)

    2008-07-30

    To evaluate the importance of the extracellular matrix in relation to heavy metal binding capacity in extreme acidic environments, the extracellular polymeric substances (EPS) composition of 12 biofilms isolated from Rio Tinto (SW, Spain) was analyzed. Each biofilm was composed mainly by one or two species of eukaryotes, although other microorganisms were present. EPS ranged from 130 to 439 mg g{sup -1} biofilm dry weight, representing between 15% and the 40% of the total biofilm dry weight (DW). Statistically significant differences (p < 0.05) were found in the amount of total EPS extracted from biofilms dominated by the same organism at different sampling points. The amount of EPS varied among different biofilms collected from the same sampling location. Colloidal EPS ranged from 42 to 313 mg g{sup -1} dry weight; 10% to 30% of the total biofilm dry weight. Capsular EPS ranged from 50 to 318 mg g{sup -1} dry weight; 5% to 30% of the total biofilm dry weight. Seven of the 12 biofilms showed higher amounts of capsular than colloidal EPS (p < 0.05). Total amount of EPS decreased when total cell numbers and pH increased. There was a positive correlation between EPS concentration and heavy metal concentration in the water. Observations by low temperature scanning electron microscopy (LTSEM) revealed the mineral adsorption in the matrix of EPS and onto the cell walls. EPS in all biofilms were primarily composed of carbohydrates, heavy metals and humic acid, plus small quantities of proteins and DNA. After carbohydrates, heavy metals were the second main constituents of the extracellular matrix. Their total concentrations ranged from 3 to 32 mg g{sup -1} biofilm dry weight, reaching up to 16% of the total composition. In general, the heavy metal composition of the EPS extracted from the biofilms closely resembled the metal composition of the water from which the biofilms were collected.

  7. The Expression of Bone Morphogenetic Protein 2 and Matrix Metalloproteinase 2 through Retinoic Acid Receptor Beta Induced by All-Trans Retinoic Acid in Cultured ARPE-19 Cells.

    Directory of Open Access Journals (Sweden)

    Zhenya Gao

    Full Text Available All-trans retinoic acid (ATRA plays an important role in ocular development. Previous studies found that retinoic acid could influence the metabolism of scleral remodeling by promoting retinal pigment epithelium (RPE cells to secrete secondary signaling factors. The purpose of this study was to investigate whether retinoic acid affected secretion of bone morphogenetic protein 2 (BMP-2 and matrix metalloproteinase 2 (MMP-2 and to explore the signaling pathway of retinoic acid in cultured acute retinal pigment epithelial 19 (ARPE-19 cells.The effects of ATRA (concentrations from 10-9 to 10-5 mol/l on the expression of retinoic acid receptors (RARs in ARPE-19 cells were examined at the mRNA and protein levels using reverse transcription-polymerase chain reaction (RT-PCR and western blot assay, respectively. The effects of treating ARPE-19 cells with ATRA concentrations ranging from 10-9 to 10-5 mol/l for 24 h and 48 h or with 10-6mol/l ATRA at different times ranging from 6h to 72h were assessed using real-time quantitative PCR (qPCR and enzyme-linked immunosorbent assay (ELISA. The contribution of RARβ-induced activation of ARPE-19 cells was confirmed using LE135, an antagonist of RARβ.RARβ mRNA levels significantly increased in the ARPE-19 cells treated with ATRA for 24h and 48h. These increases in RARβ mRNA levels were dose dependent (at concentrations of 10-9 to 10-5 mol/l with a maximum effect observed at 10-6 mol/l. There were no significant changes in the mRNA levels of RARα and RARγ. Western blot assay revealed that RARβ protein levels were increased significantly in a time-dependent manner in ARPE-19 cells treated with 10-6 mol/l ATRA from 12 h to 72 h, with a marked increase observed at 24 h and 48 h. The upregulation of RARβ and the ATRA-induced secretion in ARPE-19 cells could be inhibited by the RARβ antagonist LE135.ATRA induced upregulation of RARβ in ARPE-19 cells and stimulated these cells to secrete BMP-2 and MMP-2.

  8. 10-Hydroxy-2-decenoic acid prevents ultraviolet A-induced damage and matrix metalloproteinases expression in human dermal fibroblasts.

    Science.gov (United States)

    Zheng, Jinfen; Lai, Wei; Zhu, Guoxing; Wan, Miaojian; Chen, Jian; Tai, Yan; Lu, Chun

    2013-10-01

    10-Hydroxy-2-decenoic acid (10-HDA) is a major fatty acid component of royal jelly, which has been reported to have a variety of beneficial pharmacological characteristics. However, the effects of 10-HDA on skin photoageing and its potential mechanism of action are unclear. We investigated the protective effects of 10-HDA on ultraviolet (UV) A-induced damage in human dermal fibroblasts (HDFs). We then explored the inhibitory effects of 10-HDA on UVA-induced matrix metalloproteinases (MMPs) expression and elucidated the signalling pathways controlling MMPs inhibition. Primary human dermal fibroblasts were exposed to UVA. Cell proliferation, cellular senescent state and collagen content were analysed using CCK-8, senescence-associated β-galactosidase staining and Sircol collagen assay, respectively. Fluorometric assays were performed to detect the formation of reactive oxygen species (ROS) in the cells. The mRNA levels of MMP-1, MMP-3 and type I (α1) collagen were determined by quantitative real-time PCR. Western blot was applied to detect the expression of MMP-1, MMP-3, JNK and p38 MAPK. HDFs treated with 10-HDA were significantly protected from UVA-induced cytotoxicity, ROS, cellular senescence and stimulated collagen production. Moreover, 10-HDA suppressed the UVA-induced expression of MMP-1 and MMP-3 at both the transcriptional and protein levels. Treatment with 10-HDA also reduced the UVA-induced activation of the JNK and p38 MAPK pathways. The data obtained in this study provide evidence that 10-HDA could prevent UVA-induced damage and inhibit MMP-1 and MMP-3 expressions. Therefore, 10-HDA may be a potential agent for the prevention and treatment of skin photoageing. © 2012 The Authors. Journal of the European Academy of Dermatology and Venereology © 2012 European Academy of Dermatology and Venereology.

  9. Cis-12-oxo-phytodienoic acid stimulates rice defense response to a piercing-sucking insect.

    Science.gov (United States)

    Guo, Hui-Min; Li, Hai-Chao; Zhou, Shi-Rong; Xue, Hong-Wei; Miao, Xue-Xia

    2014-11-01

    The brown planthopper (BPH, Nilaparvata lugens) is a destructive, monophagous, piercing-sucking insect pest of rice. Previous studies indicated that jasmonic acid (JA) positively regulates rice defense against chewing insect pests but negatively regulates it against the piercing-sucking insect of BPH. We here demonstrated that overexpression of allene oxide cyclase (AOC) but not OPR3 (cis-12-oxo-phytodienoic acid (OPDA) reductase 3, an enzyme adjacent to AOC in the JA synthetic pathway) significantly increased rice resistance to BPH, mainly by reducing the feeding activity and survival rate. Further analysis revealed that plant response to BPH under AOC overexpression was independent of the JA pathway and that significantly higher OPDA levels stimulated rice resistance to BPH. Microarray analysis identified multiple candidate resistance-related genes under AOC overexpression. OPDA treatment stimulated the resistance of radish seedlings to green peach aphid Myzus persicae, another piercing-sucking insect. These results imply that rice resistance to chewing insects and to sucking insects can be enhanced simultaneously through AOC-mediated increases of JA and OPDA and provide direct evidence of the potential application of OPDA in stimulating plant defense responses to piercing-sucking insect pests in agriculture. © The Author 2014. Published by the Molecular Plant Shanghai Editorial Office in association with Oxford University Press on behalf of CSPB and IPPE, SIBS, CAS.

  10. Postvagotomy acid secretion and mucosal blood flow during beta-adrenoceptor stimulation and universal chemical sympathectomy in dogs

    DEFF Research Database (Denmark)

    Hovendal, C P

    1983-01-01

    The aim of the present study was to examine the effect of beta-adrenoceptor stimulation, alpha blockade, and elimination of the adrenergic nerve function on mucosal blood flow and acid secretion in parietal-cell-vagotomized (PCV) gastric fistula dogs. Isoprenaline inhibited pentagastrin-stimulate......The aim of the present study was to examine the effect of beta-adrenoceptor stimulation, alpha blockade, and elimination of the adrenergic nerve function on mucosal blood flow and acid secretion in parietal-cell-vagotomized (PCV) gastric fistula dogs. Isoprenaline inhibited pentagastrin...... to chemical sympathectomy with 6-hydroxy-dopamine, a false neurotransmitter that selectively destroys the adrenergic nerve terminals. Chemical sympathectomy increased the pentagastrin-stimulated gastric acid secretion and stabilized the mucosal blood flow at the level before vagotomy, but with an increased...... ratio between blood flow and acid secretion. One may conclude that the sympathetic nerve system influences gastric function after vagotomy....

  11. Stimulation of the Salicylic Acid Pathway Aboveground Recruits Entomopathogenic Nematodes Belowground.

    Directory of Open Access Journals (Sweden)

    Camila Cramer Filgueiras

    Full Text Available Plant defense pathways play a critical role in mediating tritrophic interactions between plants, herbivores, and natural enemies. While the impact of plant defense pathway stimulation on natural enemies has been extensively explored aboveground, belowground ramifications of plant defense pathway stimulation are equally important in regulating subterranean pests and still require more attention. Here we investigate the effect of aboveground stimulation of the salicylic acid pathway through foliar application of the elicitor methyl salicylate on belowground recruitment of the entomopathogenic nematode, Steinernema diaprepesi. Also, we implicate a specific root-derived volatile that attracts S. diaprepesi belowground following aboveground plant stimulation by an elicitor. In four-choice olfactometer assays, citrus plants treated with foliar applications of methyl salicylate recruited S. diaprepesi in the absence of weevil feeding as compared with negative controls. Additionally, analysis of root volatile profiles of citrus plants receiving foliar application of methyl salicylate revealed production of d-limonene, which was absent in negative controls. The entomopathogenic nematode S. diaprepesi was recruited to d-limonene in two-choice olfactometer trials. These results reinforce the critical role of plant defense pathways in mediating tritrophic interactions, suggest a broad role for plant defense pathway signaling belowground, and hint at sophisticated plant responses to pest complexes.

  12. Stimulation of the Salicylic Acid Pathway Aboveground Recruits Entomopathogenic Nematodes Belowground

    Science.gov (United States)

    Filgueiras, Camila Cramer; Willett, Denis S.; Junior, Alcides Moino; Pareja, Martin; Borai, Fahiem El; Dickson, Donald W.; Stelinski, Lukasz L.; Duncan, Larry W.

    2016-01-01

    Plant defense pathways play a critical role in mediating tritrophic interactions between plants, herbivores, and natural enemies. While the impact of plant defense pathway stimulation on natural enemies has been extensively explored aboveground, belowground ramifications of plant defense pathway stimulation are equally important in regulating subterranean pests and still require more attention. Here we investigate the effect of aboveground stimulation of the salicylic acid pathway through foliar application of the elicitor methyl salicylate on belowground recruitment of the entomopathogenic nematode, Steinernema diaprepesi. Also, we implicate a specific root-derived volatile that attracts S. diaprepesi belowground following aboveground plant stimulation by an elicitor. In four-choice olfactometer assays, citrus plants treated with foliar applications of methyl salicylate recruited S. diaprepesi in the absence of weevil feeding as compared with negative controls. Additionally, analysis of root volatile profiles of citrus plants receiving foliar application of methyl salicylate revealed production of d-limonene, which was absent in negative controls. The entomopathogenic nematode S. diaprepesi was recruited to d-limonene in two-choice olfactometer trials. These results reinforce the critical role of plant defense pathways in mediating tritrophic interactions, suggest a broad role for plant defense pathway signaling belowground, and hint at sophisticated plant responses to pest complexes. PMID:27136916

  13. Extracellular S100A4(mts1) stimulates invasive growth of mouse endothelial cells and modulates MMP-13 matrix metalloproteinase activity

    DEFF Research Database (Denmark)

    Schmidt-Hansen, Birgitte; Ornås, Dorte; Grigorian, Mariam

    2004-01-01

    with the transcriptional modulation of genes involved in the proteolytic degradation of extracellular matrix (ECM). Treatment of SVEC 4-10 with the S100A4 protein leads to the transcriptional activation of collagenase 3 (MMP-13) mRNA followed by subsequent release of the protein from the cells. Beta-casein zymography...... demonstrates enhancement of proteolytic activity associated with MMP-13. This observation indicates that extracellular S100A4 stimulates the production of ECM degrading enzymes from endothelial cells, thereby stimulating the remodeling of ECM. This could explain the angiogenic and metastasis...

  14. An Autologous Bone Marrow Mesenchymal Stem Cell–Derived Extracellular Matrix Scaffold Applied with Bone Marrow Stimulation for Cartilage Repair

    Science.gov (United States)

    Tang, Cheng; Jin, Chengzhe; Du, Xiaotao; Yan, Chao; Min, Byoung-Hyun; Xu, Yan

    2014-01-01

    Purpose: It is well known that implanting a bioactive scaffold into a cartilage defect site can enhance cartilage repair after bone marrow stimulation (BMS). However, most of the current scaffolds are derived from xenogenous tissue and/or artificial polymers. The implantation of these scaffolds adds risks of pathogen transmission, undesirable inflammation, and other immunological reactions, as well as ethical issues in clinical practice. The current study was undertaken to evaluate the effectiveness of implanting autologous bone marrow mesenchymal stem cell–derived extracellular matrix (aBMSC-dECM) scaffolds after BMS for cartilage repair. Methods: Full osteochondral defects were performed on the trochlear groove of both knees in 24 rabbits. One group underwent BMS only in the right knee (the BMS group), and the other group was treated by implantation of the aBMSC-dECM scaffold after BMS in the left knee (the aBMSC-dECM scaffold group). Results: Better repair of cartilage defects was observed in the aBMSC-dECM scaffold group than in the BMS group according to gross observation, histological assessments, immunohistochemistry, and chemical assay. The glycosaminoglycan and DNA content, the distribution of proteoglycan, and the distribution and arrangement of type II and I collagen fibers in the repaired tissue in the aBMSC-dECM scaffold group at 12 weeks after surgery were similar to that surrounding normal hyaline cartilage. Conclusions: Implanting aBMSC-dECM scaffolds can enhance the therapeutic effect of BMS on articular cartilage repair, and this combination treatment is a potential method for successful articular cartilage repair. PMID:24666429

  15. Evidence for a central 5-hydroxytryptamine receptor stimulation by lysergic acid diethylamide

    Science.gov (United States)

    Andén, N.-E.; Corrodi, H.; Fuxe, K.; Hökfelt, T.

    1968-01-01

    1. Lysergic acid diethylamide (LSD) and the 5-hydroxytryptamine (5-HT) precursor, 5-hydroxytryptophan produced similar functional effects in rat spinal cord and brain to the 5-hydroxytryptamine precursor 5-hydroxytryptophan, which indicates that LSD stimulates central 5-HT receptors. 2. By means of combined histochemical and biochemical techniques it was found that LSD reduced the turnover rate of brain and spinal cord 5-HT, studied after inhibition of the tryptophan hydroxylase by α-propyldopacetamide. The turnover of brain noradrenaline but not dopamine was somewhat accelerated. 3. The functional and chemical effects by LSD were related to dose and to time. They were not observed after the LSD analogues 2-bromo-LSD and methylsergide. 4. The retardation of the 5-HT turnover by LSD may be due to negative feed-back mechanisms evoked by direct stimulation of the central 5-HT receptors. ImagesFIG. 1FIG. 2 PMID:5302837

  16. Thyroid hormone reduces PCSK9 and stimulates bile acid synthesis in humans[S

    Science.gov (United States)

    Bonde, Ylva; Breuer, Olof; Lütjohann, Dieter; Sjöberg, Stefan; Angelin, Bo; Rudling, Mats

    2014-01-01

    Reduced plasma LDL-cholesterol is a hallmark of hyperthyroidism and is caused by transcriptional stimulation of LDL receptors in the liver. Here, we investigated whether thyroid hormone (TH) actions involve other mechanisms that may also account for the reduction in LDL-cholesterol, including effects on proprotein convertase subtilisin/kexin type 9 (PCSK9) and bile acid synthesis. Twenty hyperthyroid patients were studied before and after clinical normalization, and the responses to hyperthyroidism were compared with those in 14 healthy individuals after 14 days of treatment with the liver-selective TH analog eprotirome. Both hyperthyroidism and eprotirome treatment reduced circulating PCSK9, lipoprotein cholesterol, apoB and AI, and lipoprotein(a), while cholesterol synthesis was stable. Hyperthyroidism, but not eprotirome treatment, markedly increased bile acid synthesis and reduced fibroblast growth factor (FGF) 19 and dietary cholesterol absorption. Eprotirome treatment, but not hyperthyroidism, reduced plasma triglycerides. Neither hyperthyroidism nor eprotirome treatment altered insulin, glucose, or FGF21 levels. TH reduces circulating PSCK9, thereby likely contributing to lower plasma LDL-cholesterol in hyperthyroidism. TH also stimulates bile acid synthesis, although this response is not critical for its LDL-lowering effect. PMID:25172631

  17. Lactic acid bacteria in dairy food: surface characterization and interactions with food matrix components.

    Science.gov (United States)

    Burgain, J; Scher, J; Francius, G; Borges, F; Corgneau, M; Revol-Junelles, A M; Cailliez-Grimal, C; Gaiani, C

    2014-11-01

    This review gives an overview of the importance of interactions occurring in dairy matrices between Lactic Acid Bacteria and milk components. Dairy products are important sources of biological active compounds of particular relevance to human health. These compounds include immunoglobulins, whey proteins and peptides, polar lipids, and lactic acid bacteria including probiotics. A better understanding of interactions between bioactive components and their delivery matrix may successfully improve their transport to their target site of action. Pioneering research on probiotic lactic acid bacteria has mainly focused on their host effects. However, very little is known about their interaction with dairy ingredients. Such knowledge could contribute to designing new and more efficient dairy food, and to better understand relationships between milk constituents. The purpose of this review is first to provide an overview of the current knowledge about the biomolecules produced on bacterial surface and the composition of the dairy matter. In order to understand how bacteria interact with dairy molecules, adhesion mechanisms are subsequently reviewed with a special focus on the environmental conditions affecting bacterial adhesion. Methods dedicated to investigate the bacterial surface and to decipher interactions between bacteria and abiotic dairy components are also detailed. Finally, relevant industrial implications of these interactions are presented and discussed. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Differential stimulation of luminol-enhanced chemiluminescence (CL) and arachidonic acid metabolism in rat peritoneal neutrophils

    Energy Technology Data Exchange (ETDEWEB)

    Sturm, R.J.; Adams, L.M.; Cullinan, C.A.; Berkenkopf, J.W.; Weichman, B.M.

    1986-03-05

    Phorbol 12-myristate, 13-acetate (PMA) induced the production of radical oxygen species (ROS) from rat peritoneal neutrophils as assessed by CL. ROS generation occurred in a time- (maximum at 13.5 min) and dose- (concentration range of 1.7-498 nM) related fashion. However, 166 nM PMA did not induce either cyclooxygenase (CO) or lipoxygenase (LPO) product formation by 20 min post-stimulation. Conversely, A23187, at concentrations between 0.1 and 10 ..mu..M, stimulated both pathways of arachidonic acid metabolism, but had little or no effect upon ROS production. When suboptimal concentrations of PMA (5.5 nM) and A23187 (0.1-1 ..mu..M) were coincubated with the neutrophils, a synergistic ROS response was elicited. However, arachidonic acid metabolism in the presence of PMA was unchanged relative to A12187 alone. Nordihydroguaiaretic acid (NDGA) inhibited both PMA-induced CL (IC/sub 50/ = 0.9 ..mu..M) and A23187-induced arachidonic acid metabolism (IC/sub 50/ = 1.7 ..mu..M and 6.0 ..mu..M for LPO and CO, respectively). The mixed LPO-CO inhibitor, BW755C, behaved in a qualitatively similar manner to NDGA, whereas the CO inhibitors, indomethacin, piroxicam and naproxen had no inhibitory effect on ROS generation at concentrations as high as 100 ..mu..M. These results suggest that NDGA and BW755C may inhibit CL and arachidonic acid metabolism by distinct mechanisms in rat neutrophils.

  19. Thrombin stimulates albumin transcytosis in lung microvascular endothelial cells via activation of acid sphingomyelinase.

    Science.gov (United States)

    Kuebler, Wolfgang M; Wittenberg, Claudia; Lee, Warren L; Reppien, Eike; Goldenberg, Neil M; Lindner, Karsten; Gao, Yizhuo; Winoto-Morbach, Supandi; Drab, Marek; Mühlfeld, Christian; Dombrowsky, Heike; Ochs, Matthias; Schütze, Stefan; Uhlig, Stefan

    2016-04-15

    Transcellular albumin transport occurs via caveolae that are abundant in lung microvascular endothelial cells. Stimulation of albumin transcytosis by proinflammatory mediators may contribute to alveolar protein leak in lung injury, yet the regulation of albumin transport and its underlying molecular mechanisms are so far incompletely understood. Here we tested the hypothesis that thrombin may stimulate transcellular albumin transport across lung microvascular endothelial cells in an acid-sphingomyelinase dependent manner. Thrombin increased the transport of fluorescently labeled albumin across confluent human lung microvascular endothelial cell (HMVEC-L) monolayers to an extent that markedly exceeds the rate of passive diffusion. Thrombin activated acid sphingomyelinase (ASM) and increased ceramide production in HMVEC-L, but not in bovine pulmonary artery cells, which showed little albumin transport in response to thrombin. Thrombin increased total caveolin-1 (cav-1) content in both whole cell lysates and lipid rafts from HMVEC-L, and this effect was blocked by inhibition of ASM or de novo protein biosynthesis. Thrombin-induced uptake of albumin into lung microvascular endothelial cells was confirmed in isolated-perfused lungs by real-time fluorescence imaging and electron microscopy of gold-labeled albumin. Inhibition of ASM attenuated thrombin-induced albumin transport both in confluent HMVEC-L and in intact lungs, whereas HMVEC-L treatment with exogenous ASM increased albumin transport and enriched lipid rafts in cav-1. Our findings indicate that thrombin stimulates transcellular albumin transport in an acid sphingomyelinase-dependent manner by inducing de novo synthesis of cav-1 and its recruitment to membrane lipid rafts. Copyright © 2016 the American Physiological Society.

  20. Z-sinapinic acid: the change of the stereochemistry of cinnamic acids as rational synthesis of a new matrix for carbohydrate MALDI-MS analysis.

    Science.gov (United States)

    Salum, María L; Itovich, Lucia M; Erra-Balsells, Rosa

    2013-11-01

    Successful application of matrix-assisted laser desorption/ionization (MALDI) MS started with the introduction of efficient matrices such as cinnamic acid derivatives (i.e. 3,5-dimethoxy-4-hydroxycinnamic acid, SA; α-cyano-4-hydroxycinnamic acid). Since the empirical founding of these matrices, other commercial available cinnamic acids with different nature and location of substituents at benzene ring were attempted. Rational design and synthesis of new cinnamic acids have been recently described too. Because the presence of a rigid double bond in its molecule structure, cinnamic acids can exist as two different geometric isomers, the E-form and Z-form. Commercial available cinnamic acids currently used as matrices are the geometric isomers trans or E (E-cinnamic and trans-cinnamic acids). As a new rational design of MALDI matrices, Z-cinnamic acids were synthesized, and their properties as matrices were studied. Their performance was compared with that of the corresponding E-isomer and classical crystalline matrices (3,5-dihydroxybenzoic acid; norharmane) in the analysis of neutral/sulfated carbohydrates. Herein, we demonstrate the outstanding performance for Z-SA. Sulfated oligosaccharides were detected in negative ion mode, and the dissociation of sulfate groups was almost suppressed. Additionally, to better understand the quite different performance of each geometric isomer as matrix, the physical and morphological properties as well as the photochemical stability in solid state were studied. The influence of the E/Z photoisomerization of the matrix during MALDI was evaluated. Finally, molecular modeling (density functional theory study) of the optimized geometry and stereochemistry of E-cinnamic and Z-cinnamic acids revealed some factors governing the analyte-matrix interaction. Copyright © 2013 John Wiley & Sons, Ltd.

  1. Uric Acid Stimulates Fructokinase and Accelerates Fructose Metabolism in the Development of Fatty Liver

    Science.gov (United States)

    Lanaspa, Miguel A.; Sanchez-Lozada, Laura G.; Cicerchi, Christina; Li, Nanxing; Roncal-Jimenez, Carlos A.; Ishimoto, Takuji; Le, Myphuong; Garcia, Gabriela E.; Thomas, Jeffrey B.; Rivard, Christopher J.; Andres-Hernando, Ana; Hunter, Brandi; Schreiner, George; Rodriguez-Iturbe, Bernardo; Sautin, Yuri Y.; Johnson, Richard J.

    2012-01-01

    Excessive dietary fructose intake may have an important role in the current epidemics of fatty liver, obesity and diabetes as its intake parallels the development of these syndromes and because it can induce features of metabolic syndrome. The effects of fructose to induce fatty liver, hypertriglyceridemia and insulin resistance, however, vary dramatically among individuals. The first step in fructose metabolism is mediated by fructokinase (KHK), which phosphorylates fructose to fructose-1-phosphate; intracellular uric acid is also generated as a consequence of the transient ATP depletion that occurs during this reaction. Here we show in human hepatocytes that uric acid up-regulates KHK expression thus leading to the amplification of the lipogenic effects of fructose. Inhibition of uric acid production markedly blocked fructose-induced triglyceride accumulation in hepatocytes in vitro and in vivo. The mechanism whereby uric acid stimulates KHK expression involves the activation of the transcription factor ChREBP, which, in turn, results in the transcriptional activation of KHK by binding to a specific sequence within its promoter. Since subjects sensitive to fructose often develop phenotypes associated with hyperuricemia, uric acid may be an underlying factor in sensitizing hepatocytes to fructose metabolism during the development of fatty liver. PMID:23112875

  2. Oxidizing gel formulation for nuclear decontamination: rheological and acidic properties of the organic matrix and its ozonolysis

    International Nuclear Information System (INIS)

    Rouy, E.

    2003-10-01

    An acidic and oxidizing gel was formulated with a purely organic matrix, xanthan gum, at low concentrations (1 to 2 wt %). This polymer gel was investigated in various media (aqueous, acidic and ceric) by means of rheology: shear thinning behaviour, thixotropy, yield stress... Evidences of unexpected rheological properties in highly concentrated media show that xanthan is quite convenient for industrial projection of this type of gel on metallic walls in nuclear plants, notwithstanding its time-limited resistance to oxidation (about a few hours). Complexation mechanisms between ceric species and polar sites of the polymer led us to characterise acidic properties of our xanthan sample by potentiometric titration and 1 H NMR techniques. The matrix was finally treated by ozonolysis to suppress organic residues, as required to handle nuclear wastes. In acidic medium, ozonolysis of the gel was achieved successfully while in acidic and ceric medium this process showed limited efficiency, needing further investigation to be clarified. (author)

  3. Activation of transmembrane bile acid receptor TGR5 stimulates insulin secretion in pancreatic β cells

    International Nuclear Information System (INIS)

    Kumar, Divya P.; Rajagopal, Senthilkumar; Mahavadi, Sunila; Mirshahi, Faridoddin; Grider, John R.; Murthy, Karnam S.; Sanyal, Arun J.

    2012-01-01

    Highlights: ► G protein coupled receptor TGR5 is expressed in mouse and human islets. ► TGR5 is coupled to activation of Gs and Ca 2+ release via cAMP/Epac/PLC-ε pathway. ► Activation of TGR5 by bile salts and selective ligands causes insulin secretion. ► TGR5 could be a potential therapeutic target to treat diabetes. -- Abstract: Bile acids act as signaling molecules and stimulate the G protein coupled receptor, TGR5, in addition to nuclear farnesoid X receptor to regulate lipid, glucose and energy metabolism. Bile acid induced activation of TGR5 in the enteroendocrine cells promotes glucagon like peptide-1 (GLP-1) release, which has insulinotropic effect in the pancreatic β cells. In the present study, we have identified the expression of TGR5 in pancreatic β cell line MIN6 and also in mouse and human pancreatic islets. TGR5 selective ligands, oleanolic acid (OA) and INT-777 selectively activated Gα s and caused an increase in intracellular cAMP and Ca 2+ . OA and INT-777 also increased phosphoinositide (PI) hydrolysis and the increase was blocked by NF449 (a selective Gα s inhibitor) or (U73122) (PI hydrolysis inhibitor). OA, INT-777 and lithocholic acid increased insulin release in MIN6 and human islets and the increase was inhibited by treatment with NF449, (U73122) or BAPTA-AM (chelator of calcium), but not with myristoylated PKI (PKA inhibitor), suggesting that the release is dependent on G s /cAMP/Ca 2+ pathway. 8-pCPT-2′-O-Me-cAMP, a cAMP analog, which activates Epac, but not PKA also stimulated PI hydrolysis. In conclusion, our study demonstrates that the TGR5 expressed in the pancreatic β cells regulates insulin secretion and highlights the importance of ongoing therapeutic strategies targeting TGR5 in the control of glucose homeostasis.

  4. Differential expression of lactic acid isomers, extracellular matrix metalloproteinase inducer, and matrix metalloproteinase-8 in vaginal fluid from women with vaginal disorders.

    Science.gov (United States)

    Beghini, J; Linhares, I M; Giraldo, P C; Ledger, W J; Witkin, S S

    2015-11-01

    Do metabolites in vaginal samples vary between women with different vaginal disorders. Cross-sectional study. Campinas, Brazil. Seventy-seven women (39.9%) with no vaginal disorder, 52 women (26.9%) with vulvovaginal candidiasis (VVC), 43 women (22.3%) with bacterial vaginosis (BV), and 21 women (10.9%) with cytolytic vaginosis (CTV). Concentrations of D- and L-lactic acid, extracellular matrix metalloproteinase inducer (EMMPRIN), and matrix metalloproteinase-8 (MMP-8), and the influence of Candida albicans on EMMPRIN production by cultured vaginal epithelial cells, were determined by enzyme-linked immunosorbent assay (ELISA). Associations were determined by the Mann-Whitney U-test and by Spearman's rank correlation test. Metabolite levels and their correlation with diagnoses. Vaginal concentrations of D- and L-lactic acid were reduced from control levels in BV (P vaginal epithelial cells. Vaginal secretions from women with BV are deficient in D- and L-lactic acid, women with VVC have elevated EMMPRIN and MMP-8 levels, and women with CTV have elevated L-lactic acid levels. These deviations may contribute to the clinical signs, symptoms, and sequelae that are characteristic of these disorders. © 2014 Royal College of Obstetricians and Gynaecologists.

  5. Suprathel-acetic acid matrix versus acticoat and aquacel as an antiseptic dressing: an in vitro study.

    Science.gov (United States)

    Ryssel, Henning; Germann, Günter; Riedel, Katrin; Reichenberger, Matthias; Hellmich, Susanne; Kloeters, Oliver

    2010-10-01

    The treatment of burn wounds is still a challenge regarding the management of antiseptic wound conditioning. Especially, in the United States, silver-containing dressings, such as Acticoat and Aquacel are frequently used. Because silver-containing dressings have well-known drawbacks such as an antimicrobial lack against Pseudomonas aeruginosa, we sought to develop an alternative dressing method. In previous studies, we could demonstrate the excellent antiseptic properties of acetic acid against common burn unit germs, and in another study, the feasibility and suitability of a Suprathel-acetic acid matrix as an antiseptic dressing. This study was designed to test the in vitro antimicrobial effect of a Suprathel-acetic acid matrix versus Acticoat and Aquacel. To cover the typical bacterial spectrum of a burn unit, the following Gram-negative and Gram-positive bacteria strains were tested: Escherichia coli, extended-spectrum beta-lactamase-positive Klebsiella pneumoniae, P. aeruginosa, Acinetobacter baumannii, Enterococcus faecalis, and methicillin-resistant Staphylococcus aureus. The tests showed an excellent bactericidal effect of the Suprathel-acetic acid matrix particularly with problematic Gram-negative bacteria such as Proteus vulgaris, P. aeruginosa, and Acinetobacter baumannii. The efficiency was superior to that of Acicoat and Aquacel. Our results support the notion, that the Suprathel-acetic acid matrix has an excellent bactericidal effect and therefore seems to be suitable as a local antiseptic agent in the treatment of burn wounds.

  6. Effect of dopamine on bethanechol-stimulated gastric mucosal blood flow and gastric acid secretion in dogs with gastric fistula

    DEFF Research Database (Denmark)

    Hovendal, C P; Bech, K

    1982-01-01

    of gastric mucosal blood flow, whereas stimulation of beta, muscarinic, and 'gastrinergic' receptors mainly occurs indirectly via changes in parietal cell function. The main effect of dopamine seems to be on gastric motility, whereas the effect on gastric acid secretion is of minor importance.......The aim of the present study was to investigate the effect of Dopamine on bethanechol-stimulated gastric acid secretion and mucosal blood flow. dopamine was used alone and in conjunction with selective blockade of the alpha, beta, and dopaminergic receptors. An increasing and dose......-dependent stimulation of gastric acid secretion was found for dopamine at 1, 5, and 10 micrograms/kg/min. A significant inhibition of gastric acid secretion was found with the highest dose of dopamine (40 micrograms/kg/min). the stimulatory effect seems to be mediated by more than one receptor, whereas the inhibition...

  7. Neuromuscular electrical stimulation prior to presleep protein feeding stimulates the use of protein-derived amino acids for overnight muscle protein synthesis.

    Science.gov (United States)

    Dirks, Marlou L; Groen, Bart B L; Franssen, Rinske; van Kranenburg, Janneau; van Loon, Luc J C

    2017-01-01

    Short periods of muscle disuse result in substantial skeletal muscle atrophy. Recently, we showed that both neuromuscular electrical stimulation (NMES) as well as presleep dietary protein ingestion represent effective strategies to stimulate muscle protein synthesis rates. In this study, we test our hypothesis that NMES can augment the use of presleep protein-derived amino acids for overnight muscle protein synthesis in older men. Twenty healthy, older [69 ± 1 (SE) yr] men were subjected to 24 h of bed rest, starting at 8:00 AM. In the evening, volunteers were subjected to 70-min 1-legged NMES, while the other leg served as nonstimulated control (CON). Immediately following NMES, 40 g of intrinsically l-[1- 13 C]-phenylalanine labeled protein was ingested prior to sleep. Blood samples were taken throughout the night, and muscle biopsies were obtained from both legs in the evening and the following morning (8 h after protein ingestion) to assess dietary protein-derived l-[1- 13 C]-phenylalanine enrichments in myofibrillar protein. Plasma phenylalanine concentrations and plasma l-[1- 13 C]-phenylalanine enrichments increased significantly following protein ingestion and remained elevated for up to 6 h after protein ingestion (P protein-bound l-[1- 13 C]-phenylalanine enrichments (MPE) increased to a greater extent in the stimulated compared with the control leg (0.0344 ± 0.0019 vs. 0.0297 ± 0.0016 MPE, respectively; P protein-derived amino acids in the NMES compared with CON leg. In conclusion, application of NMES prior to presleep protein feeding stimulates the use of dietary protein-derived amino acids for overnight muscle protein synthesis in older men. Neuromuscular electrical stimulation (NMES) as well as presleep dietary protein ingestion represent effective strategies to stimulate muscle protein synthesis rates. Here we demonstrate that in older men after a day of bed rest, the application of NMES prior to presleep protein feeding stimulates the use of

  8. Amino acids augment muscle protein synthesis in neonatal pigs during acute endotoxemia by stimulating mTOR-dependent translation initiation.

    Science.gov (United States)

    Orellana, Renán A; Jeyapalan, Asumthia; Escobar, Jeffery; Frank, Jason W; Nguyen, Hanh V; Suryawan, Agus; Davis, Teresa A

    2007-11-01

    In skeletal muscle of adults, sepsis reduces protein synthesis by depressing translation initiation and induces resistance to branched-chain amino acid stimulation. Normal neonates maintain a high basal muscle protein synthesis rate that is sensitive to amino acid stimulation. In the present study, we determined the effect of amino acids on protein synthesis in skeletal muscle and other tissues in septic neonates. Overnight-fasted neonatal pigs were infused with endotoxin (LPS, 0 and 10 microg.kg(-1).h(-1)), whereas glucose and insulin were maintained at fasting levels; amino acids were clamped at fasting or fed levels. In the presence of fasting insulin and amino acids, LPS reduced protein synthesis in longissimus dorsi (LD) and gastrocnemius muscles and increased protein synthesis in the diaphragm, but had no effect in masseter and heart muscles. Increasing amino acids to fed levels accelerated muscle protein synthesis in LD, gastrocnemius, masseter, and diaphragm. LPS stimulated protein synthesis in liver, lung, spleen, pancreas, and kidney in fasted animals. Raising amino acids to fed levels increased protein synthesis in liver of controls, but not LPS-treated animals. The increase in muscle protein synthesis in response to amino acids was associated with increased mTOR, 4E-BP1, and S6K1 phosphorylation and eIF4G-eIF4E association in control and LPS-infused animals. These findings suggest that amino acids stimulate skeletal muscle protein synthesis during acute endotoxemia via mTOR-dependent ribosomal assembly despite reduced basal protein synthesis rates in neonatal pigs. However, provision of amino acids does not further enhance the LPS-induced increase in liver protein synthesis.

  9. Plasma Amino Acids Stimulate Uncoupled Respiration of Muscle Subsarcolemmal Mitochondria in Lean but Not Obese Humans.

    Science.gov (United States)

    Kras, Katon A; Hoffman, Nyssa; Roust, Lori R; Patel, Shivam H; Carroll, Chad C; Katsanos, Christos S

    2017-12-01

    Obesity is associated with mitochondrial dysfunction in skeletal muscle. Increasing the plasma amino acid (AA) concentrations stimulates mitochondrial adenosine triphosphate (ATP) production in lean individuals. To determine whether acute elevation in plasma AAs enhances muscle mitochondrial respiration and ATP production in subsarcolemmal (SS) and intermyofibrillar (IMF) mitochondria in obese adults. Assessment of SS and IMF mitochondrial function during saline (i.e., control) and AA infusions. Eligible participants were healthy lean (body mass index, mass index >30 kg/m2; age 35 ± 3 years; n = 11) subjects. Single trial of saline infusion followed by AA infusion. SS and IMF mitochondria were isolated from muscle biopsies collected at the end of the saline and AA infusions. Mitochondrial respiration and ATP production. AA infusion increased adenosine 5'-diphosphate (ADP)-stimulated respiration and ATP production rates of SS mitochondria in the lean (P lean subjects only (P lean or obese subjects (P > 0.05). Increasing the plasma AA concentrations enhances the capacity for respiration and ATP production of muscle SS, but not IMF, mitochondria in lean individuals, in parallel with increases in uncoupled respiration. However, neither of these parameters increases in muscle SS or IMF mitochondria in obese individuals. Copyright © 2017 Endocrine Society

  10. Activation of transmembrane bile acid receptor TGR5 stimulates insulin secretion in pancreatic {beta} cells

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Divya P.; Rajagopal, Senthilkumar; Mahavadi, Sunila [Department of Physiology and Biophysics, Virginia Commonwealth University School of Medicine, Richmond, VA (United States); Mirshahi, Faridoddin [Division of Gastroenterology, Hepatology and Nutrition, Department of Internal Medicine, Virginia Commonwealth University School of Medicine, Richmond, VA (United States); Grider, John R. [Department of Physiology and Biophysics, Virginia Commonwealth University School of Medicine, Richmond, VA (United States); Murthy, Karnam S., E-mail: skarnam@vcu.edu [Department of Physiology and Biophysics, Virginia Commonwealth University School of Medicine, Richmond, VA (United States); Sanyal, Arun J., E-mail: asanyal@mcvh-vcu.edu [Division of Gastroenterology, Hepatology and Nutrition, Department of Internal Medicine, Virginia Commonwealth University School of Medicine, Richmond, VA (United States)

    2012-10-26

    Highlights: Black-Right-Pointing-Pointer G protein coupled receptor TGR5 is expressed in mouse and human islets. Black-Right-Pointing-Pointer TGR5 is coupled to activation of Gs and Ca{sup 2+} release via cAMP/Epac/PLC-{epsilon} pathway. Black-Right-Pointing-Pointer Activation of TGR5 by bile salts and selective ligands causes insulin secretion. Black-Right-Pointing-Pointer TGR5 could be a potential therapeutic target to treat diabetes. -- Abstract: Bile acids act as signaling molecules and stimulate the G protein coupled receptor, TGR5, in addition to nuclear farnesoid X receptor to regulate lipid, glucose and energy metabolism. Bile acid induced activation of TGR5 in the enteroendocrine cells promotes glucagon like peptide-1 (GLP-1) release, which has insulinotropic effect in the pancreatic {beta} cells. In the present study, we have identified the expression of TGR5 in pancreatic {beta} cell line MIN6 and also in mouse and human pancreatic islets. TGR5 selective ligands, oleanolic acid (OA) and INT-777 selectively activated G{alpha}{sub s} and caused an increase in intracellular cAMP and Ca{sup 2+}. OA and INT-777 also increased phosphoinositide (PI) hydrolysis and the increase was blocked by NF449 (a selective G{alpha}{sub s} inhibitor) or (U73122) (PI hydrolysis inhibitor). OA, INT-777 and lithocholic acid increased insulin release in MIN6 and human islets and the increase was inhibited by treatment with NF449, (U73122) or BAPTA-AM (chelator of calcium), but not with myristoylated PKI (PKA inhibitor), suggesting that the release is dependent on G{sub s}/cAMP/Ca{sup 2+} pathway. 8-pCPT-2 Prime -O-Me-cAMP, a cAMP analog, which activates Epac, but not PKA also stimulated PI hydrolysis. In conclusion, our study demonstrates that the TGR5 expressed in the pancreatic {beta} cells regulates insulin secretion and highlights the importance of ongoing therapeutic strategies targeting TGR5 in the control of glucose homeostasis.

  11. Extracellular matrix assembly in extreme acidic eukaryotic biofilms and their possible implications in heavy metal adsorption

    International Nuclear Information System (INIS)

    Aguilera, Angeles; Souza-Egipsy, Virginia; San Martin-Uriz, Patxi; Amils, Ricardo

    2008-01-01

    To evaluate the importance of the extracellular matrix in relation to heavy metal binding capacity in extreme acidic environments, the extracellular polymeric substances (EPS) composition of 12 biofilms isolated from Rio Tinto (SW, Spain) was analyzed. Each biofilm was composed mainly by one or two species of eukaryotes, although other microorganisms were present. EPS ranged from 130 to 439 mg g -1 biofilm dry weight, representing between 15% and the 40% of the total biofilm dry weight (DW). Statistically significant differences (p -1 dry weight; 10% to 30% of the total biofilm dry weight. Capsular EPS ranged from 50 to 318 mg g -1 dry weight; 5% to 30% of the total biofilm dry weight. Seven of the 12 biofilms showed higher amounts of capsular than colloidal EPS (p -1 biofilm dry weight, reaching up to 16% of the total composition. In general, the heavy metal composition of the EPS extracted from the biofilms closely resembled the metal composition of the water from which the biofilms were collected

  12. Inhibition of matrix metalloproteinases expression in human dental pulp cells by all-trans retinoic acid

    Institute of Scientific and Technical Information of China (English)

    Jin Man Kim; Sang Wook Kang; Su-Mi Shin; Duck Su Kim; Kyong-Kyu Choi; Eun-Cheol Kim; Sun-Young Kim

    2014-01-01

    All-trans retinoic acid (ATRA) inhibits matrix metalloproteinase (MMP)-2 and MMP-9 in synovial fibroblasts, skin fibroblasts, bronchoalveolar lavage cells and cancer cells, but activates MMP-9 in neuroblast and leukemia cells. Very little is known regarding whether ATRA can activate or inhibit MMPs in human dental pulp cells (HDPCs). The purpose of this study was to determine the effects of ATRA on the production and secretion of MMP-2 and-9 in HDPCs. The productions and messenger RNA (mRNA) expressions of MMP-2 and-9 were accessed by gelatin zymography and real-time polymerase chain reaction (PCR), respectively. ATRA was found to decrease MMP-2 level in a dose-dependent manner. Significant reduction in MMP-2 mRNA expression was also observed in HDPCs treated with 25 mmol?L21 ATRA. However, HDPCs treated with ATRA had no effect on the pattern of MMP-9 produced or secreted in either cell extracts or conditioned medium fractions. Taken together, ATRA had an inhibitory effect on MMP-2 expression in HDPCs, which suggests that ATRA could be a candidate as a medicament which could control the inflammation of pulp tissue in vital pulp therapy and regenerative endodontics.

  13. Hydrophobic silica nanoparticles as reinforcing filler for poly (lactic acid polymer matrix

    Directory of Open Access Journals (Sweden)

    Pilić Branka M.

    2016-01-01

    Full Text Available Properties of poly (lactic acid (PLA and its nanocomposites, with silica nanoparticles (SiO2, as filler were investigated. Neat PLA films and PLA films with different percentage of hydrophobic fumed silica nanoparticles (0.2, 0.5, 1, 2, 3 and 5 wt. % were prepared by solution casting method. Several tools were used to characterize the influence of different silica content on crystalline behavior, and thermal, mechanical and barrier properties of PLA/SiO2 nanocomposites. Results from scanning electron microscope (SEM showed that the nanocomposite preparation and selection of specific hydrophobic spherical nano filler provide a good dispersion of the silica nanoparticles in the PLA matrix. Addition of silica nanoparticles improved mechanical properties, the most significant improvement being observed for lowest silica content (0.2wt.%. Barrier properties were improved for all measured gases at all loadings of silica nanoparticles. The degree of crystallinity for PLA slightly increased by adding 0.2 and 0.5 wt. % of nano filler. [Projekat Ministarstva nauke Republike Srbije, br. III46001

  14. Effects of exogenous hyaluronic acid and serum on matrix organization and stability in the mouse cumulus cell-oocyte complex.

    Science.gov (United States)

    Camaioni, A; Hascall, V C; Yanagishita, M; Salustri, A

    1993-09-25

    Compact cumulus cell-oocyte complexes (COCs) isolated from preovulatory mouse follicles undergo expansion in vitro when high levels of hyaluronic acid (HA) are synthesized and organized into an extracellular matrix. We studied the effects of fetal bovine serum (FBS) and of exogenous HA and HA-oligomers on the expansion process. Maximum retention of HA in the COC matrix, and hence complete COC expansion, occurs when 1% FBS is continuously present during the first 18 h of culture. Irrespective of the culture time, HA synthesized when serum is absent is primarily in the medium, whereas HA synthesized when serum is present is primarily in the cell matrix. These findings support the hypothesis that the serum factor, identified as an inter-alpha-trypsin inhibitor by Chen et al. (Chen, L., Mao, S. J., and Larsen, W. J. (1992) J. Biol. Chem. 267, 12380-12386), is a structural component of the matrix. Addition of exogenous HA or of HA oligomers of decasaccharide size (GlcUA-GlcNAc)5 or larger effectively displaces endogenously synthesized HA from the matrix into the medium, thereby preventing COC expansion. Addition of exogenous chondroitin sulfate affects neither matrix organization nor COC expansion, thus indicating specificity of the binding of some structural component(s) to HA. Fully expanded COCs disassemble when cultured longer than 18 h, a process which occurs also in vivo and which correlates with loss of oocyte fertilizability both in vivo and in vitro. This process involves release of macromolecular HA from the matrix into the medium, with loss of 50% of the HA in the first 8 h of incubation after full expansion. The release is not facilitated when HA oligomers, long enough to prevent matrix formation, are added to the culture medium after the COCs are fully expanded. This suggests that cooperative binding to HA of either the serum factor, an endogenously synthesized factor(s), or both is required to stabilize the fully expanded COC matrix.

  15. Gallic Acid Inhibited Matrix Invasion and AP-1/ETS-1-Mediated MMP-1 Transcription in Human Nasopharyngeal Carcinoma Cells.

    Science.gov (United States)

    Pang, Jong-Hwei S; Yen, Jia-Hau; Wu, Hsiao-Ting; Huang, Sheng-Teng

    2017-06-24

    Gallic acid is a trihydroxybenzoic acid found in natural herbal plants. Gallic acid has been reported to inhibit the migration and invasive capability of various cancers. Little is known about the underlying mechanisms of invasion responsible for cancer metastasis via gallic acid. The present study was intended to investigate the anti-invasive effect of gallic acid on human nasopharyngeal carcinoma cells (NPC-BM1) and its related mechanism. Gallic acid inhibited the invasion of NPC-BM1 cells dose- and time-dependently without significant cytotoxic effect. Affymetrix oligonucleotide microarray analysis revealed matrix metalloproteinase-1 (MMP-1) as the most down-regulated gene in NPC-BM1 cells by gallic acid. The cytosolic and secreted MMP-1 levels were both found to be inhibited by gallic acid as demonstrated by western blot analysis and ELISA respectively. The mRNA expression and transcription of MMP-1 gene was also down-regulated as determined by RT/real-time PCR and promoter activity assay. The expression of two major transcription binding factors in the MMP-1 promoter, AP-1 and ETS-1, were demonstrated to be reduced by gallic acid in NPC-BM1 cells. The effect of gallic acid was associated with the inhibition of p38 MAPK signaling pathway. In addition, gallic acid enhanced the gene expression of tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) which further suppressed the MMP-1 activity. These findings may be useful to develop a novel chemotherapeutic agent to inhibit the metastasis of nasopharyngeal cancer.

  16. Transforming growth factor-beta stimulates wound healing and modulates extracellular matrix gene expression in pig skin. I. Excisional wound model.

    Science.gov (United States)

    Quaglino, D; Nanney, L B; Kennedy, R; Davidson, J M

    1990-09-01

    The effect of transforming growth factor-beta 1 (TGF-beta 1) on matrix gene expression has been investigated during the process of wound repair, where the formation of new connective tissue represents a critical step in restoring tissue integrity. Split-thickness excisional wounds in the pig were studied by in situ hybridization in order to obtain subjective findings on the activity and location of cells involved in matrix gene expression after the administration of recombinant TGF-beta 1. Data focus on the stimulatory role of this growth factor in granulation tissue formation, on the enhanced mRNA content of collagen types I and III, fibronectin, TGF-beta 1 itself, and on the reduction in stromelysin mRNA, suggesting that increased matrix formation measured after treatment with TGF-beta 1 is due to fibroplasia regulated by the abundance of mRNAs for several different structural, matrix proteins as well as inhibition of proteolytic phenomena elicited by metalloproteinases. These studies reveal elastin mRNA early in the repair process, and elastin mRNA expression is enhanced by administration of TGF-beta 1. Moreover, we show that TGF-beta 1 was auto-stimulating in wounds, accounting, at least in part, for the persistent effects of single doses of this multipotential cytokine.

  17. Porous or roughened electrode with an assigned matrix for electrochemical cells with acid electrolytes, especially fuel cell batteries

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, H; Fleischmann, R

    1975-10-16

    According to the invention an electrolyte matrix is to be used, which experiences a definite increase in volume by swelling, and fits on to the electrode in such a way that it is closely meshed with it. Matrix materials treated with sulphuric acid are claimed, such as 1) polystyrol, polyethelyne, polyvinyl alcohol, polyvinyl acetate, methyl cellulose or polyester, which are used alone or compounded with silica gel, aluminium oxide or sea sand, and 2) zeolite, silica, aluminium dioxide, titanium dioxide or zirconium dioxide using binding materials.

  18. A novel viscoelastic surfactant suitable for use in high temperature carbonate reservoirs for diverted acidizing stimulation treatments

    Energy Technology Data Exchange (ETDEWEB)

    Holt, Stuart; Zhou, Jian; Gadberry, Fred [AkzoNobel Surface Chemistry, Forth Worth, TX (United States); Nasr-El-Din, Hisham; Wang, Guanqun [Texas A and M University, College Station, TX (United States). Dept. of Petroleum Engineering

    2012-07-01

    Due to the low permeability of many carbonate hydrocarbon-bearing reservoirs, it is difficult to achieve economic hydrocarbon recovery from a well without secondary stimulation. Bullheading of strong acids, such as HCl is practiced in low temperature reservoirs, but as the bottom hole temperature (BHT) rises, the acid becomes increasingly corrosive, causing facial dissolution and sub-optimal wormhole network development. In the last decade, viscoelastic surfactants (VES) have been added to HCl acid systems to improve the stimulation of HT carbonate reservoirs. The VES form 'living polymers' or worm-like micelles as electrolyte concentration rises in the acid due to reaction with the reservoir. This leads to viscosification of the stimulation fluid. The viscosification slows further acid reaction in the region already contacted by the acid, and forces the acid to take an alternate path into the rock, leading to diversion of the acids further down the well to the harder to access toe or lower permeability zones. Until recently, the maximum BHT that such VES-based diverting systems could be used was up to about 250 deg F/120 deg C. Above that temperature, all viscous properties of the fluid are lost, destroying the mechanism of acid diversion. A recently developed novel viscoelastic surfactant provides nearly 100 deg F/55 deg C extension in the BHT range in which diverted acid treatments can be used. These fluids are able to maintain both viscosity up to about 375 deg F/190 deg C, with the elastic modulus predominating up to 350 deg F/175 deg C. It is the elasticity which is particularly important in acid diversion. These fluids can have their viscosity readily broken by in-situ hydrocarbons, dilution with water or by using a mutual solvent. The broken fluids are readily removed from the near-well bore, leaving the newly created wormhole network to produce the target hydrocarbons. The new VES is significantly more environmentally benign compared with current

  19. Lipoxygenase-mediated pro-radical effect of melatonin via stimulation of arachidonic acid metabolism

    International Nuclear Information System (INIS)

    Radogna, F.; Sestili, P.; Martinelli, C.; Paolillo, M.; Paternoster, L.; Albertini, M.C.; Accorsi, A.; Gualandi, G.; Ghibelli, L.

    2009-01-01

    We have shown that melatonin immediately and transiently stimulates intracellular free radical production on a set of leukocytes, possibly as a consequence of calmodulin binding. We show here that melatonin-induced ROS are produced by lipoxygenase (LOX), since they are prevented by a set of LOX inhibitors, and are accompanied by increase of the 5-LOX product 5-HETE. LOX activation is accompanied by strong liberation of AA; inhibition of Ca 2+ -independent, but not Ca 2+ -dependent, phospholipase A2 (PLA2), prevents both melatonin-induced arachidonic acid and ROS production, whereas LOX inhibition only prevents ROS, indicating that PLA2 is upstream with respect to LOX, as occurs in many signaling pathways. Chlorpromazine, an inhibitor of melatonin-calmodulin interaction, inhibits both ROS and arachidonic acid production, thus possibly placing calmodulin at the origin of a melatonin-induced pro-radical pathway. Interestingly, it is known that Ca 2+ -independent PLA2 binds to calmodulin: our results are compatible with PLA2 being liberated by melatonin from a steady-state calmodulin sequestration, thus initiating an arachidonate signal transduction. These results delineate a novel molecular pathway through which melatonin may participate to the inflammatory response.

  20. Effects of ultraviolet irradiation on bonding strength between Co-Cr alloy and citric acid-crosslinked gelatin matrix.

    Science.gov (United States)

    Inoue, Motoki; Sasaki, Makoto; Katada, Yasuyuki; Taguchi, Tetsushi

    2014-02-01

    Novel techniques for creating a strong bond between polymeric matrices and biometals are required. We immobilized polymeric matrices on the surface of biometal for drug-eluting stents through covalent bond. We performed to improve the bonding strength between a cobalt-chromium alloy and a citric acid-crosslinked gelatin matrix by ultraviolet irradiation on the surface of cobalt-chromium alloy. The ultraviolet irradiation effectively generated hydroxyl groups on the surface of the alloy. The bonding strength between the gelatin matrix and the alloy before ultraviolet irradiation was 0.38 ± 0.02 MPa, whereas it increased to 0.48 ± 0.02 MPa after ultraviolet irradiation. Surface analysis showed that the citric acid derivatives occurred on the surface of the cobalt-chromium alloy through ester bond. Therefore, ester bond formation between the citric acid derivatives active esters and the hydroxyl groups on the cobalt-chromium alloy contributed to the enhanced bonding strength. Ultraviolet irradiation and subsequent immobilization of a gelatin matrix using citric acid derivatives is thus an effective way to functionalize biometal surfaces.

  1. Acid stimulation (sour taste elicits GABA and serotonin release from mouse taste cells.

    Directory of Open Access Journals (Sweden)

    Yijen A Huang

    Full Text Available Several transmitter candidates including serotonin (5-HT, ATP, and norepinephrine (NE have been identified in taste buds. Recently, γ-aminobutyric acid (GABA as well as the associated synthetic enzymes and receptors have also been identified in taste cells. GABA reduces taste-evoked ATP secretion from Receptor cells and is considered to be an inhibitory transmitter in taste buds. However, to date, the identity of GABAergic taste cells and the specific stimulus for GABA release are not well understood. In the present study, we used genetically-engineered Chinese hamster ovary (CHO cells stably co-expressing GABA(B receptors and Gαqo5 proteins to measure GABA release from isolated taste buds. We recorded robust responses from GABA biosensors when they were positioned against taste buds isolated from mouse circumvallate papillae and the buds were depolarized with KCl or a stimulated with an acid (sour taste. In contrast, a mixture of sweet and bitter taste stimuli did not trigger GABA release. KCl- or acid-evoked GABA secretion from taste buds was Ca(2+-dependent; removing Ca(2+ from the bathing medium eliminated GABA secretion. Finally, we isolated individual taste cells to identify the origin of GABA secretion. GABA was released only from Presynaptic (Type III cells and not from Receptor (Type II cells. Previously, we reported that 5-HT released from Presynaptic cells inhibits taste-evoked ATP secretion. Combined with the recent findings that GABA depresses taste-evoked ATP secretion, the present results indicate that GABA and 5-HT are inhibitory transmitters in mouse taste buds and both likely play an important role in modulating taste responses.

  2. The earthworm Aporrectodea caliginosa stimulates abundance and activity of phenoxyalkanoic acid herbicide degraders

    Science.gov (United States)

    Liu, Ya-Jun; Zaprasis, Adrienne; Liu, Shuang-Jiang; Drake, Harold L; Horn, Marcus A

    2011-01-01

    2-Methyl-4-chlorophenoxyacetic acid (MCPA) is a widely used phenoxyalkanoic acid (PAA) herbicide. Earthworms represent the dominant macrofauna and enhance microbial activities in many soils. Thus, the effect of the model earthworm Aporrectodea caliginosa (Oligochaeta, Lumbricidae) on microbial MCPA degradation was assessed in soil columns with agricultural soil. MCPA degradation was quicker in soil with earthworms than without earthworms. Quantitative PCR was inhibition-corrected per nucleic acid extract and indicated that copy numbers of tfdA-like and cadA genes (both encoding oxygenases initiating aerobic PAA degradation) in soil with earthworms were up to three and four times higher than without earthworms, respectively. tfdA-like and 16S rRNA gene transcript copy numbers in soil with earthworms were two and six times higher than without earthworms, respectively. Most probable numbers (MPNs) of MCPA degraders approximated 4 × 105 gdw−1 in soil before incubation and in soil treated without earthworms, whereas MPNs of earthworm-treated soils were approximately 150 × higher. The aerobic capacity of soil to degrade MCPA was higher in earthworm-treated soils than in earthworm-untreated soils. Burrow walls and 0–5 cm depth bulk soil displayed higher capacities to degrade MCPA than did soil from 5–10 cm depth bulk soil, expression of tfdA-like genes in burrow walls was five times higher than in bulk soil and MCPA degraders were abundant in burrow walls (MPNs of 5 × 107 gdw−1). The collective data indicate that earthworms stimulate abundance and activity of MCPA degraders endogenous to soil by their burrowing activities and might thus be advantageous for enhancing PAA degradation in soil. PMID:20740027

  3. Cogels of Hyaluronic Acid and Acellular Matrix for Cultivation of Adipose-Derived Stem Cells: Potential Application for Vocal Fold Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Dongyan Huang

    2016-01-01

    Full Text Available Stem cells based tissue engineering has been one of the potential promising therapies in the research on the repair of tissue diseases including the vocal fold. Decellularized extracellular matrix (DCM as a promising scaffold has be used widely in tissue engineering; however, it remained to be an important issue in vocal fold regeneration. Here, we applied the hydrogels (hyaluronic acid [HA], HA-collagen [HA-Col], and HA-DCM to determine the effects of hydrogel on the growth and differentiation of human adipose-derived stem cells (hADSCs into superficial lamina propria fibroblasts. hADSCs were isolated and characterized by fluorescence-activated cell sorting. The results indicated that HA-DCM hydrogel enhanced cell proliferation and prolonged cell morphology significantly compared to HA and HA-Col hydrogel. Importantly, the differentiation of hADSCs into fibroblasts was also promoted by cogels of HA-Col and HA-DCM significantly. The differentiation of hADSCs towards superficial lamina propria fibroblasts was accelerated by the secretion of HGF, IL-8, and VEGF, the decorin and elastin expression, and the synthesis of chondroitin sulfate significantly. Therefore, the cogel of HA-DCM hydrogel was shown to be outstanding in apparent stimulation of hADSCs proliferation and differentiation to vocal fold fibroblasts through secretion of important growth factors and synthesis of extracellular matrix.

  4. Lysine and pipecolic acid and some of their derivatives show anticonvulsant activity, and stimulation of benzodiazepine receptor activity

    International Nuclear Information System (INIS)

    Chang, Yung-Feng; Gao, Xue-Min

    1989-01-01

    Benzodiazepines are one of the most widely prescribed drugs in the treatment of anxiety, epilepsy and muscle tension. The natural products lysine and pipecolic acid known to be present in the animal, plant and microorganism, have been shown to be anticonvulsant against pentetrazol (PTZ)-induced seizures in mice. Methyl and ethyl esters of L-lysine and the N-isopropanol derivative of pipecolic acid appear to increase the anticonvulsant potency of the parent compounds, presumably due to their increase in hydrophobicity. Lysine and pipecolic acid showed significant stimulation of specific [ 3 H]flunitrazepam (FZ) binding to mouse brain membranes. This stimulation was enhanced by chloride ions and stereospecific with L-isomer having higher effect. The dose-dependent anticonvulsant activity of lysine and pipecolic acid, and their stimulation of [ 3 H]FZ binding appear to be correlated. The antiepileptic activity lysine, pipecolic acid and their derivatives therefore may be mediated through the γ-aminobutyric acid-benzodiazepine receptor complex

  5. Adhesion dynamics of porcine esophageal fibroblasts on extracellular matrix protein-functionalized poly(lactic acid)

    International Nuclear Information System (INIS)

    Cai Ning; Gong Yingxue; Chan, Vincent; Liao Kin; Chian, Kerm Sin

    2008-01-01

    Effective attachment of esophageal cells on biomaterials is one important requirement in designing engineered esophagus substitute for esophageal cancer treatment. In this study, poly(lactic acid) (PLA) was subjected to surface modification by coupling extracellular matrix (ECM) proteins on its surface to promote cell adhesion. Two typical ECM proteins, collagen type I (COL) and fibronectin (FN), were immobilized on the PLA surface with the aid of glutaraldehyde as a cross linker between aminolyzed PLA and ECM proteins. By using confocal reflectance interference contrast microscopy (C-RICM) integrating with phase contrast microscopy, the long-term adhesion dynamics of porcine esophageal fibroblasts (PEFs) on four types of surfaces (unmodified PLA, PLA-COOH, PLA-COL and PLA-FN) was investigated during 24 h of culture. It is demonstrated by C-RICM results that PEFs form strong adhesion contact on all four types of surfaces at different stages of cell seeding. Among the four surfaces, PEFs on the PLA-FN surface reach the maximum adhesion energy (9.5 x 10 -7 J m -2 ) in the shortest time (20 min) during the initial stage of cell seeding. After adhesion energy reaches the maximum value, PEFs maintain their highly deformed geometries till they reached a steady state after 20 h of culture. F-actin immunostaining results show that the evolvement of spatial organization of F-actin is tightly correlated with the formation of adhesion contact and cell spreading. Furthermore, the cell attachment ratio of PEFs on PLA in 2 h is only 26% compared with 88% on PLA-FN, 73% on PLA-COL and 36% on PLA-COOH. All the results demonstrate the effect of surface functionalization on the biophysical responses of PEFs in cell adhesion. Fibronectin-immobilized PLA demonstrates promising potential for application as an engineered esophagus substitute

  6. Selective stimulation of excitatory amino acid receptor subtypes and the survival of cerebellar granule cells in culture: effect of kainic acid

    DEFF Research Database (Denmark)

    Balázs, R; Hack, N; Jørgensen, Ole Steen

    1990-01-01

    Our previous studies showed that the survival of cerebellar granule cells in culture is promoted by treatment with N-methyl-D-aspartate. Here we report on the influence of another glutamate analogue, kainic acid, which, in contrast to N-methyl-D-aspartate, is believed to stimulate transmitter rec...

  7. Branched-Chain Amino Acid Ingestion Stimulates Muscle Myofibrillar Protein Synthesis following Resistance Exercise in Humans

    Directory of Open Access Journals (Sweden)

    Sarah R. Jackman

    2017-06-01

    Full Text Available The ingestion of intact protein or essential amino acids (EAA stimulates mechanistic target of rapamycin complex-1 (mTORC1 signaling and muscle protein synthesis (MPS following resistance exercise. The purpose of this study was to investigate the response of myofibrillar-MPS to ingestion of branched-chain amino acids (BCAAs only (i.e., without concurrent ingestion of other EAA, intact protein, or other macronutrients following resistance exercise in humans. Ten young (20.1 ± 1.3 years, resistance-trained men completed two trials, ingesting either 5.6 g BCAA or a placebo (PLA drink immediately after resistance exercise. Myofibrillar-MPS was measured during exercise recovery with a primed, constant infusion of L-[ring13C6] phenylalanine and collection of muscle biopsies pre and 4 h-post drink ingestion. Blood samples were collected at time-points before and after drink ingestion. Western blotting was used to measure the phosphorylation status of mTORC1 signaling proteins in biopsies collected pre, 1-, and 4 h-post drink. The percentage increase from baseline in plasma leucine (300 ± 96%, isoleucine (300 ± 88%, and valine (144 ± 59% concentrations peaked 0.5 h-post drink in BCAA. A greater phosphorylation status of S6K1Thr389 (P = 0.017 and PRAS40 (P = 0.037 was observed in BCAA than PLA at 1 h-post drink ingestion. Myofibrillar-MPS was 22% higher (P = 0.012 in BCAA (0.110 ± 0.009%/h than PLA (0.090 ± 0.006%/h. Phenylalanine Ra was ~6% lower in BCAA (18.00 ± 4.31 μmol·kgBM−1 than PLA (21.75 ± 4.89 μmol·kgBM−1; P = 0.028 after drink ingestion. We conclude that ingesting BCAAs alone increases the post-exercise stimulation of myofibrillar-MPS and phosphorylation status mTORC1 signaling.

  8. Impressic acid from Acanthopanax koreanum, possesses matrix metalloproteinase-13 down-regulating capacity and protects cartilage destruction.

    Science.gov (United States)

    Lim, Hyun; Min, Dong Suk; Yun, Han Eul; Kim, Kil Tae; Sun, Ya Nan; Dat, Le Duc; Kim, Young Ho; Kim, Hyun Pyo

    2017-09-14

    Acanthopanax koreanum (Araliaceae) has been used in traditional medicine for enhancing vitality, rheumatism, and bone-related pains. But its activity on cartilage protection has not been known yet. Matrix metalloproteinase (MMP)-13 has an important role in degrading cartilage materials under pathologic conditions such as arthritis. The present study was designed to find the inhibitory activity of impressic acid on MMP-13 expression and cartilage protective action. 70% ethanol extract of Acanthopanax koreanum leaves and impressic acid, a major constituent isolated from the same plant materials, were examined on MMP-13 down-regulating capacity in IL-1β-treated human chondrocyte cell line (SW1353) and rabbit cartilage explants. In IL-1β-treated SW1353 cells, impressic acid significantly and concentration-dependently inhibited MMP-13 expression at 0.5-10μM. Impressic acid was found to be able to inhibit MMP-13 expression by blocking the phosphorylation of signal transducer and activator of transcription-1/-2 (STAT-1/-2) and activation of c-Jun and c-Fos among the cellular signaling pathways involved. Further, impressic acid was found to inhibit the expression of MMP-13 mRNA (47.7% inhibition at 10μM), glycosaminoglycan release (42.2% reduction at 10μM) and proteoglycan loss in IL-1-treated rabbit cartilage explants culture. In addition, a total of 21 lupane-type triterpenoids structurally-related to impressic acid were isolated from the same plant materials and their suppressive activities against MMP-13 expression were also examined. Among these derivatives, compounds 2, 3, 16, and 18 clearly down-regulated MMP-13 expression. However, impressic acid was more potent than these derivatives in down-regulating MMP-13 expression. Impressic acid, its related triterpenoids, and A. koreanum extract have potential as therapeutic agents to prevent cartilage degradation by inhibiting matrix protein degradation. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  9. A Novel Acidic Matrix Protein, PfN44, Stabilizes Magnesium Calcite to Inhibit the Crystallization of Aragonite*

    Science.gov (United States)

    Pan, Cong; Fang, Dong; Xu, Guangrui; Liang, Jian; Zhang, Guiyou; Wang, Hongzhong; Xie, Liping; Zhang, Rongqing

    2014-01-01

    Magnesium is widely used to control calcium carbonate deposition in the shell of pearl oysters. Matrix proteins in the shell are responsible for nucleation and growth of calcium carbonate crystals. However, there is no direct evidence supporting a connection between matrix proteins and magnesium. Here, we identified a novel acidic matrix protein named PfN44 that affected aragonite formation in the shell of the pearl oyster Pinctada fucata. Using immunogold labeling assays, we found PfN44 in both the nacreous and prismatic layers. In shell repair, PfN44 was repressed, whereas other matrix proteins were up-regulated. Disturbing the function of PfN44 by RNAi led to the deposition of porous nacreous tablets with overgrowth of crystals in the nacreous layer. By in vitro circular dichroism spectra and fluorescence quenching, we found that PfN44 bound to both calcium and magnesium with a stronger affinity for magnesium. During in vitro calcium carbonate crystallization and calcification of amorphous calcium carbonate, PfN44 regulated the magnesium content of crystalline carbonate polymorphs and stabilized magnesium calcite to inhibit aragonite deposition. Taken together, our results suggested that by stabilizing magnesium calcite to inhibit aragonite deposition, PfN44 participated in P. fucata shell formation. These observations extend our understanding of the connections between matrix proteins and magnesium. PMID:24302723

  10. Serum amyloid A stimulates matrix-metalloproteinase-9 upregulation via formyl peptide receptor like-1-mediated signaling in human monocytic cells

    International Nuclear Information System (INIS)

    Lee, Ha Young; Kim, Mi-Kyoung; Park, Kyoung Sun; Bae, Yun Hee; Yun, Jeanho; Park, Joo-In; Kwak, Jong-Young; Bae, Yoe-Sik

    2005-01-01

    In the present study, we found that serum amyloid A (SAA) stimulated matrix-metalloproteinase-9 (MMP-9) upregulation at the transcription and translational levels in THP-1 cells. SAA stimulated the activation of nuclear factor κB (NF-κB), which was required for the MMP-9 upregulation by SAA. The signaling events induced by SAA included the activation of ERK and intracellular calcium rise, which were found to be required for MMP-9 upregulation. Formyl peptide receptor like 1 (FPRL1) was found to be involved in the upregulation of MMP-9 by SAA. Among several FPRL1 agonists, including Trp-Lys-Tyr-Met-Val-D-Met (WKYMVm), SAA selectively stimulated MMP-9 upregulation. With respect to the molecular mechanisms involved in the differential action of SAA and WKYMVm, we found that SAA could not competitively inhibit the binding of 125 I-labeled WKYMVm to FPRL1. Taken together, we suggest that SAA plays a role in the modulation of inflammatory and immune responses via FPRL1, by inducing MMP-9 upregulation in human monocytic cells

  11. Experiences from the acid stimulation of geothermal aquifers and plants; Erfahrungen bei der Saeurestimulation geothermaler Aquifere und Anlagen

    Energy Technology Data Exchange (ETDEWEB)

    Wolfgramm, Markus; Birner, Johannes; Lenz, Gerhard; Hoffmann, Frank; Rinke, Manfred [Geothermie Neubrandenburg GmbH, Berlin (Germany)

    2012-10-16

    In the course of the exploration of geothermal aquifers up to the operation of geothermal power plants, the utilization of acids and other substances such as inhibitors or powerful oxidants to secure enhanced productivities are of great significance. At the molasses basin, drillings which explore the carbonates of the Malm are stimulated repeatedly by means of hydrochloric acid after the sinking. Information from the drilling operation such as mud losses and cutting analyses are the basis for the design of stimulations. The subsequent implementation of test operations (cleaning lift, casing-lift-test in several stages) is used to estimate the short production run and the efficiency of the specific acidification. It also can be decided whether further acidifications are reasonable. Within the operation of geothermal power plants, different failures occur in the drillings as well as in the aboveground facility components. Failures can be minimized by means of the production management and inhibitors. Nevertheless, not all reasons of the scaling can be excluded fully so that regular measures are necessary in order to eliminate the failures. These measures range from mechanical methods through the combined utilization of mechanical-chemical procedures up to different methods of acidification. Beside the so-called soft acidification, stimulations via 'coiled tubing' or via utilization of acid threads with 'packer' also are possible. The investigation of the causes of the operational disturbances as well as the correct planning of the measures are significant for the application of the said stimulation processes.

  12. MMP-sensitive PEG diacrylate hydrogels with spatial variations in matrix properties stimulate directional vascular sprout formation.

    Directory of Open Access Journals (Sweden)

    Michael V Turturro

    Full Text Available The spatial presentation of immobilized extracellular matrix (ECM cues and matrix mechanical properties play an important role in directed and guided cell behavior and neovascularization. The goal of this work was to explore whether gradients of elastic modulus, immobilized matrix metalloproteinase (MMP-sensitivity, and YRGDS cell adhesion ligands are capable of directing 3D vascular sprout formation in tissue engineered scaffolds. PEGDA hydrogels were engineered with mechanical and biofunctional gradients using perfusion-based frontal photopolymerization (PBFP. Bulk photopolymerized hydrogels with uniform mechanical properties, degradation, and immobilized biofunctionality served as controls. Gradient hydrogels exhibited an 80.4% decrease in elastic modulus and a 56.2% decrease in immobilized YRGDS. PBFP hydrogels also demonstrated gradients in hydrogel degradation with degradation times ranging from 10-12 hours in the more crosslinked regions to 4-6 hours in less crosslinked regions. An in vitro model of neovascularization, composed of co-culture aggregates of endothelial and smooth muscle cells, was used to evaluate the effect of these gradients on vascular sprout formation. Aggregate invasion in gradient hydrogels occurred bi-directionally with sprout alignment observed in the direction parallel to the gradient while control hydrogels with homogeneous properties resulted in uniform invasion. In PBFP gradient hydrogels, aggregate sprout length was found to be twice as long in the direction parallel to the gradient as compared to the perpendicular direction after three weeks in culture. This directionality was found to be more prominent in gradient regions of increased stiffness, crosslinked MMP-sensitive peptide presentation, and immobilized YRGDS concentration.

  13. ReplacementMatrix: a web server for maximum-likelihood estimation of amino acid replacement rate matrices.

    Science.gov (United States)

    Dang, Cuong Cao; Lefort, Vincent; Le, Vinh Sy; Le, Quang Si; Gascuel, Olivier

    2011-10-01

    Amino acid replacement rate matrices are an essential basis of protein studies (e.g. in phylogenetics and alignment). A number of general purpose matrices have been proposed (e.g. JTT, WAG, LG) since the seminal work of Margaret Dayhoff and co-workers. However, it has been shown that matrices specific to certain protein groups (e.g. mitochondrial) or life domains (e.g. viruses) differ significantly from general average matrices, and thus perform better when applied to the data to which they are dedicated. This Web server implements the maximum-likelihood estimation procedure that was used to estimate LG, and provides a number of tools and facilities. Users upload a set of multiple protein alignments from their domain of interest and receive the resulting matrix by email, along with statistics and comparisons with other matrices. A non-parametric bootstrap is performed optionally to assess the variability of replacement rate estimates. Maximum-likelihood trees, inferred using the estimated rate matrix, are also computed optionally for each input alignment. Finely tuned procedures and up-to-date ML software (PhyML 3.0, XRATE) are combined to perform all these heavy calculations on our clusters. http://www.atgc-montpellier.fr/ReplacementMatrix/ olivier.gascuel@lirmm.fr Supplementary data are available at http://www.atgc-montpellier.fr/ReplacementMatrix/

  14. DBDA as a Novel Matrix for the Analyses of Small Molecules and Quantification of Fatty Acids by Negative Ion MALDI-TOF MS.

    Science.gov (United States)

    Ling, Ling; Li, Ying; Wang, Sheng; Guo, Liming; Xiao, Chunsheng; Chen, Xuesi; Guo, Xinhua

    2018-04-01

    Matrix interference ions in low mass range has always been a concern when using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to analyze small molecules (matrix, N1,N4-dibenzylidenebenzene-1,4-diamine (DBDA) was synthesized for the analyses of small molecules by negative ion MALDI-TOF MS. Notably, only neat ions ([M-H] - ) of fatty acids without matrix interference appeared in the mass spectra and the limit of detection (LOD) reached 0.3 fmol. DBDA also has great performance towards other small molecules such as amino acids, peptides, and nucleotide. Furthermore, with this novel matrix, the free fatty acids in serum were quantitatively analyzed based on the correlation curves with correlation coefficient of 0.99. In addition, UV-Vis experiments and molecular orbital calculations were performed to explore mechanism about DBDA used as matrix in the negative ion mode. The present work shows that the DBDA matrix is a highly sensitive matrix with few interference ions for analysis of small molecules. Meanwhile, DBDA is able to precisely quantify the fatty acids in real biological samples. Graphical Abstract ᅟ.

  15. Influence of β-adrenoceptor stimulation on the metabolism of C 18 unsaturated fatty acids in isolated heart of rat

    International Nuclear Information System (INIS)

    Makdissi, Samar

    1993-02-01

    The influence of stimulating β receptors on the metabolism of 18:1 n-9, 18:2 n-6 and 18:3 n-3 acids in an isolated perfused heart of a rat was studied. Experiments were carried out in two stages. In the first stage, each fatty acid was entered solely in Krebs liquid labelled with C 14 and complexed with albumin. In the second stage, isoproterenol (10 -4 M) was added to the previous mixture in order to stimulate the cardiac β-receptors. It appeared that the heart extracts each of 18:1 and 18:3 in a rate that exceeds the rate of extracting 18:2 and that the oxidation rate of 18:1 was the highest among the three studied acids which were alike in their esterification so they were all entered mainly in the triglycerid group (65-66%) and to less extend in the phospholipids (16-18%). While, the diglycerid and the free fatty acids did only form secondary compounds that would soon convert to the other groups that are more stable the reactions of double bond breakage for the 18:1 acid that converts to triple bond derivatives and 18:3 that converts to tetra, penta and hexa derivatives in the triglycerid were noticed. The 18:3 acid was the least influenced by the stimulation of β. The uptake rate of 18:2 acid was increased slightly while the 18:1 was decreased would indicate a competition between this acid ant the stored one in the cell. Also, the oxidation rate of 18:1 acid as well as the rate of entering it in the triglycerid and the phospholipids increased. In the same way, the oxidation rate of 18:2 acid increased, but its esterification turned in a way that the rate of entering it among the phospholipids increased, while the rate of entering it in the triglycerid decreased. According to what has been mentioned above, it can be said that the 18:1 plays an essential role in the production of direct power besides its role as a component of phospholipids that are deposited in the cellular membranes, while the metabolism of 18:2 acid turns-largely towards the phospholipids

  16. Ursolic acid isolated from guava leaves inhibits inflammatory mediators and reactive oxygen species in LPS-stimulated macrophages.

    Science.gov (United States)

    Kim, Min-Hye; Kim, Jin Nam; Han, Sung Nim; Kim, Hye-Kyeong

    2015-06-01

    Psidium guajava (guava) leaves have been frequently used for the treatment of rheumatism, fever, arthritis and other inflammatory conditions. The purpose of this study was to identify major anti-inflammatory compounds from guava leaf extract. The methanol extract and its hexane-, dichloromethane-, ethylacetate-, n-butanol- and water-soluble phases derived from guava leaves were evaluated to determine their inhibitory activity on nitric oxide (NO) production by RAW 264.7 cells stimulated with lipopolysaccharide (LPS). The methanol extract decreased NO production in a dose-dependent manner without cytotoxicity at a concentration range of 0-100 μg/mL. The n-butanol soluble phase was the most potent among the five soluble phases. Four compounds were isolated by reversed-phase HPLC from the n-butanol soluble phase and identified to be avicularin, guaijaverin, leucocyanidin and ursolic acid by their NMR spectra. Among these compounds, ursolic acid inhibited LPS-induced NO production in a dose-dependent manner without cytotoxity at a concentration range of 1-10 µM, but the other three compounds had no effect. Ursolic acid also inhibited LPS-induced prostaglandin E2 production. A western blot analysis showed that ursolic acid decreased the LPS-stimulated inducible nitric oxide synthase and cyclooxygenase protein levels. In addition, ursolic acid suppressed the production of intracellular reactive oxygen species in LPS-stimulated RAW 264.7 cells, as measured by flow cytometry. Taken together, these results identified ursolic acid as a major anti-inflammatory compound in guava leaves.

  17. Interleukin-1β inhibits insulin signaling and prevents insulin-stimulated system A amino acid transport in primary human trophoblasts.

    Science.gov (United States)

    Aye, Irving L M H; Jansson, Thomas; Powell, Theresa L

    2013-12-05

    Interleukin-1β (IL-1β) promotes insulin resistance in tissues such as liver and skeletal muscle; however the influence of IL-1β on placental insulin signaling is unknown. We recently reported increased IL-1β protein expression in placentas of obese mothers, which could contribute to insulin resistance. In this study, we tested the hypothesis that IL-1β inhibits insulin signaling and prevents insulin-stimulated amino acid transport in cultured primary human trophoblast (PHT) cells. Cultured trophoblasts isolated from term placentas were treated with physiological concentrations of IL-1β (10pg/ml) for 24h. IL-1β increased the phosphorylation of insulin receptor substrate-1 (IRS-1) at Ser307 (inhibitory) and decreased total IRS-1 protein abundance but did not affect insulin receptor β expression. Furthermore, IL-1β inhibited insulin-stimulated phosphorylation of IRS-1 (Tyr612, activation site) and Akt (Thr308) and prevented insulin-stimulated increase in PI3K/p85 and Grb2 protein expression. IL-1β alone stimulated cRaf (Ser338), MEK (Ser221) and Erk1/2 (Thr202/Tyr204) phosphorylation. The inflammatory pathways nuclear factor kappa B and c-Jun N-terminal kinase, which are involved in insulin resistance, were also activated by IL-1β treatment. Moreover, IL-1β inhibited insulin-stimulated System A, but not System L amino acid uptake, indicating functional impairment of insulin signaling. In conclusion, IL-1β inhibited the insulin signaling pathway by inhibiting IRS-1 signaling and prevented insulin-stimulated System A transport, thereby promoting insulin resistance in cultured PHT cells. These findings indicate that conditions which lead to increased systemic maternal or placental IL-1β levels may attenuate the effects of maternal insulin on placental function and consequently fetal growth. Published by Elsevier Ireland Ltd.

  18. Influence of ascorbic acid on in vivo amidation of alpha-melanocyte stimulating hormone in guinea pig pituitary

    DEFF Research Database (Denmark)

    Fenger, M; Hilsted, L

    1988-01-01

    The effect of ascorbic acid depletion on the amidation of alphamelanocyte stimulating hormone (alpha MSH) was studied in vivo in guinea pig pituitary. After four weeks, the concentration of ascorbic acid was 1.20 +/- 0.11 mumol/g tissue (mean +/- SD) in the pituitary and 0.34 +/- 0.07 mumol......-39) immunoreactivity was observed in the depleted guinea pigs. Gel chromatography and reversed-phase high-performance luquid chromatography showed that the alpha MSH and ACTH (1-14) immunoreactivity was of low molecular weight and partly mono- or diacetylated. Depletion of ascorbic acid had no influence on the degree...... of acetylation of alpha MSH and ACTH (1-14). It is concluded that depletion of ascorbic acid reduces the in vivo amidation of ACTH (1-14) in the guinea pig pituitary....

  19. Stimulation of germination of conidium Aspergillus niger, a citric acid producer, under the action of mutagenic factors

    International Nuclear Information System (INIS)

    Golubtsova, V.M.; Shcherbakova, E.Ya.; Smirnov, V.A.; Runkovskaya, L.Ya.

    1976-01-01

    The action of low doses of various mutagens, namely, 2% cyclophosphane solution (30 min), 1% thiophosphamide solution (30 min), 0.05% nitrosomethylurea solution (30 and 60 min), γ-rays (10 krads) and UV-rays (10000 erg/mm 2 ) stimulates germination of conidium Aspergillus niger, a citric acid producer. At the above-mentioned doses of mutagens, a minor quantity of morphological varieties are formed, and the variability value of acid production by Asp. niger is maintained at the spontaneous level

  20. Wounding stimulates ALLENE OXIDE SYNTHASE gene and increases the level of jasmonic acid in Ipomoea nil cotyledons

    Directory of Open Access Journals (Sweden)

    Emilia Wilmowicz

    2016-03-01

    Full Text Available Allene oxide synthase (AOS encodes the first enzyme in the lipoxygenase pathway, which is responsible for jasmonic acid (JA formation. In this study we report the molecular cloning and characterization of InAOS from Ipomoea nil. The full-length gene is composed of 1662 bp and encodes for 519 amino acids. The predicted InAOS contains PLN02648 motif, which is evolutionarily conserved and characteristic for functional enzymatic proteins. We have shown that wounding led to a strong stimulation of the examined gene activity in cotyledons and an increase in JA level, which suggest that this compound may be a modulator of stress responses in I. nil.

  1. Dependence of matrix effect on ionization polarity during LC-ESI-MS analysis of derivatized amino acids in some natural samples.

    Science.gov (United States)

    Oldekop, Maarja-Liisa; Rebane, Riin; Herodes, Koit

    2017-10-01

    Matrix effect, the influence of co-eluting components on the ionization efficiency of the analyte, affects the trueness and precision of the LC-ESI-MS analysis. Derivatization can reduce or eliminate matrix effect, for example, diethyl ethoxymethylenemalonate (DEEMM) derivatives have shown less matrix effect compared to other derivatives. Moreover, the use of negative ion mode can further reduce matrix effect. In order to investigate the combination of derivatization and different ionization modes, an LC-ESI-MS/MS method using alternating positive/negative ion mode was developed and validated. The analyses in positive and negative ion modes had comparable limit of quantitation values. The influence of ESI polarity on matrix effect was investigated during the analysis of 22 DEEMM-derivatized amino acids in herbal extracts and honeys. Sample dilution approach was used for the evaluation of the presence of matrix effect. Altogether, 4 honeys and 11 herbal extracts were analyzed, and the concentrations of 22 amino acids in the samples are presented. In the positive ion mode, matrix effect was observed for several amino acid derivatives and the matrix effect was stronger in honey samples compared to the herbal extracts. The negative ion mode was free from matrix effect, with only few exceptions in honeys (average relative standard deviation over all analytes and matrices was 8%; SD = 7%). The matrix effect was eliminated in the positive ion mode by sample dilution and agreement between concentrations from the two ion modes was achieved for most amino acids. In conclusion, it was shown that the combination of derivatization and negative ion mode can be a powerful tool for minimizing matrix effect in more complicated applications.

  2. Oleic acid stimulates glucagon-like peptide-1 release from enteroendocrine cells by modulating cell respiration and glycolysis.

    Science.gov (United States)

    Clara, Rosmarie; Langhans, Wolfgang; Mansouri, Abdelhak

    2016-03-01

    Glucagon-like peptide-1 (GLP-1) is a potent satiating and incretin hormone released by enteroendocrine L-cells in response to eating. Dietary fat, in particular monounsaturated fatty acids, such as oleic acid (OA), potently stimulates GLP-1 secretion from L-cells. It is, however, unclear whether the intracellular metabolic handling of OA is involved in this effect. First we determined the optimal medium for the bioenergetics measurements. Then we examined the effect of OA on the metabolism of the immortalized enteroendocrine GLUTag cell model and assessed GLP-1 release in parallel. We measured oxygen consumption rate and extracellular acidification rate in response to OA and to different metabolic inhibitors with the Seahorse extracellular flux analyzer. OA increased cellular respiration and potently stimulated GLP-1 release. The fatty acid oxidation inhibitor etomoxir did neither reduce OA-induced respiration nor affect the OA-induced GLP-1 release. In contrast, inhibition of the respiratory chain or of downstream steps of aerobic glycolysis reduced the OA-induced GLP-1 release, and an inhibition of the first step of glycolysis by addition of 2-deoxy-d-glucose even abolished it. These findings indicate that an indirect stimulation of glycolysis is crucial for the OA-induced release of GLP-1. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Acid-base-driven matrix-assisted mass spectrometry for targeted metabolomics

    Czech Academy of Sciences Publication Activity Database

    Shroff, R.; Rulíšek, Lubomír; Doubský, J.; Svatoš, Aleš

    2009-01-01

    Roč. 106, č. 25 (2009), s. 10092-10096 ISSN 0027-8424 R&D Projects: GA MŠk LC512 Institutional research plan: CEZ:AV0Z40550506 Keywords : clinical diagnostic * matrix design * positive/negative ions * MALDI Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 9.432, year: 2009

  4. Carprofen inhibits the release of matrix metalloproteinases 1, 3, and 13 in the secretome of an explant model of articular cartilage stimulated with interleukin 1β.

    Science.gov (United States)

    Williams, Adam; Smith, Julia R; Allaway, David; Harris, Pat; Liddell, Susan; Mobasheri, Ali

    2013-01-01

    Arthritic diseases are characterized by the degradation of collagenous and noncollagenous extracellular matrix (ECM) components in articular cartilage. The increased expression and activity of matrix metalloproteinases (MMPs) is partly responsible for cartilage degradation. This study used proteomics to identify inflammatory proteins and catabolic enzymes released in a serum-free explant model of articular cartilage stimulated with the pro-inflammatory cytokine interleukin 1β (IL-1β). Western blotting was used to quantify the release of selected proteins in the presence or absence of the cyclooxygenase-2 specific nonsteroidal pro-inflammatory drug carprofen. Cartilage explant cultures were established by using metacarpophalangeal joints from horses euthanized for purposes other than research. Samples were treated as follows: no treatment (control), IL-1β (10 ng/ml), carprofen (100 μg/ml), and carprofen (100 μg/ml) + IL-1β (10 ng/ml). Explants were incubated (37°C, 5% CO2) over twelve day time courses. High-throughput nano liquid chromatography/mass spectrometry/mass spectrometry uncovered candidate proteins for quantitative western blot analysis. Proteoglycan loss was assessed by using the dimethylmethylene blue (DMMB) assay, which measures the release of sulfated glycosaminoglycans (GAGs). Mass spectrometry identified MMP-1, -3, -13, and the ECM constituents thrombospondin-1 (TSP-1) and fibronectin-1 (FN1). IL-1β stimulation increased the release of all three MMPs. IL-1β also stimulated the fragmentation of FN1 and increased chondrocyte cell death (as assessed by β-actin release). Addition of carprofen significantly decreased MMP release and the appearance of a 60 kDa fragment of FN1 without causing any detectable cytotoxicity to chondrocytes. DMMB assays suggested that carprofen initially inhibited IL-1β-induced GAG release, but this effect was transient. Overall, during the two time courses, GAG release was 58.67% ± 10.91% (SD) for IL-1

  5. An electron spin resonance study of radicals formed from tetrolic acid by radiolysis in a freon matrix

    International Nuclear Information System (INIS)

    Rhodes, C.J.

    1989-01-01

    In the present study, e.s.r. spectra have been observed following γ-irradiation of dilute frozen solutions of tetrolic acid, MeC≡CCO 2 H, in CFCl 3 at 77 K. A typical spectrum is shown which we interpret in terms of an isotropic quartet from the parent radical cation. MeC≡CCo 2 H +· , and an anisotropic triplet arising from the propargyl radical, ·CH 2 C≡CCO 2 H, formed by deprotonation of the parent cation. This appears to be the first example of an alkyne radical cation to be observed in a CFCl 3 matrix. (author)

  6. Molecularly imprinted polymer-matrix nanocomposite for enantioselective electrochemical sensing of D- and L-aspartic acid.

    Science.gov (United States)

    Prasad, Bhim Bali; Srivastava, Amrita; Tiwari, Mahavir Prasad

    2013-10-01

    A new molecularly imprinted polymer-matrix (titanium dioxide nanoparticle/multiwalled carbon nanotubes) nanocomposite was developed for the modification of pencil graphite electrode as an enantioselective sensing probe for aspartic acid isomers, prevalent at ultra trace level in aqueous and real samples. The nanocomposite having many shape complementary cavities was synthesized adopting surface initiated-activators regenerated by electron transfer for atom transfer radical polymerization. The proposed sensor has high stability, nanocomposite uniformity, good reproducibility, and enhanced electrocatalytic activity to respond oxidative peak current of L-aspartic acid quantitatively by differential pulse anodic stripping voltammetry, without any cross-reactivity in real samples. Under the optimized operating conditions, the L-aspartic acid imprinted modified electrode showed a wide linear response for L-aspartic acid within the concentration range 9.98-532.72 ng mL(-1), with the minimum detection limit of 1.73-1.79 ng mL(-1) (S/N=3) in aqueous and real samples. Almost similar stringent limit (1.79 ng mL(-1)) was obtained with cerebrospinal fluid which is typical for the primitive diagnosis of neurological disorders, caused by an acute depletion of L-aspartic acid biomarker, in clinical settings. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Mixed matrix membranes for process intensification in electrodialysis of amino acids

    NARCIS (Netherlands)

    Kattan Readi, O.M.; Rolevink, Hendrikus H.M.; Nijmeijer, Dorothea C.

    2014-01-01

    BACKGROUND Amino acids are valuable intermediates in the biobased economy for the production of chemicals. Electro-membrane processes combined with enzymatic modification have been investigated as an alternative technology for the fractionation of a mixture of amino acids with almost identical

  8. TNF-α stimulates System A amino acid transport in primary human trophoblast cells mediated by p38 MAPK signaling.

    Science.gov (United States)

    Aye, Irving L M H; Jansson, Thomas; Powell, Theresa L

    2015-10-01

    Maternal obesity and gestational diabetes mellitus (GDM) increase the risk of delivering infants that are large for gestational age with greater adiposity, who are prone to the development of metabolic disease in childhood and beyond. These maternal conditions are also associated with increased levels of the proinflammatory cytokine TNF-α in maternal tissues and the placenta. Recent evidence suggests that changes in placental amino acid transport contribute to altered fetal growth. TNF-α was previously shown to stimulate System A amino acid transport in primary human trophoblasts (PHTs), however the molecular mechanisms remain unknown. In this study, we tested the hypothesis that TNF-α regulates amino acid uptake in cultured PHTs by a mitogen-activated protein kinase (MAPK)-dependent mechanism. Treatment of PHTs with TNF-α significantly increased System A amino acid transport, as well as Erk and p38 MAPK signaling. Pharmacological antagonism of p38, but not Erk MAPK activity, inhibited TNF-α stimulated System A activity. Silencing of p38 MAPK using siRNA transfections prevented TNF-α stimulated System A transport in PHTs. TNF-α significantly increased the protein expression of System A transporters SNAT1 and SNAT2, but did not affect their mRNA expression. The effects of TNF-α on SNAT1 and SNAT2 protein expression were reversed by p38 MAPK siRNA silencing. In conclusion, TNF-α regulates System A activity through increased SNAT1 and SNAT2 transporter protein expression in PHTs. These findings suggest that p38 MAPK may represent a critical mechanistic link between elevated proinflammatory cytokines and increased placental amino acid transport in obese and GDM pregnancies associated with fetal overgrowth. © 2015 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

  9. Pore formation mechanism of porous poly(DL-lactic acid) matrix membrane

    Energy Technology Data Exchange (ETDEWEB)

    Phaechamud, Thawatchai, E-mail: tphaechamud011@yahoo.com; Chitrattha, Sasiprapa, E-mail: sasi_toey@hotmail.com

    2016-04-01

    Porous PLA structure has been widely used in cell transplantation, drug carrier and wound dressing. The porous structure can be controlled depending on the choice of the polymer, solvent, nonsolvent and preparation parameters. In this study, the porous PLA matrix membranes were prepared by adding PEG 400 in PLA solution using dichloromethane (DCM) as solvent prior to casting. The influence of other liquids as co-solvent on pore formation and the structural change during membrane formation were evaluated. The co-solvents affected both porous topography and mechanical properties of PLA membrane. The porous matrix were produced when the non-solvent of PLA was used as co-solvent. Cryo-SEM micrographs revealed that PEG 400 still remained in the PLA porous matrix membrane. From the tracking of the structural change during film formation, the PLA–PEG solution changed into porous structure by liquid liquid phase separation and solidification processes, respectively. Thermogravimetric analysis revealed that PLA–PEG in DCM solution exhibited the two-step of weight loss, the first step occurred from DCM evaporation and the second step occurred from the degradation of PLA–PEG matrix. The liquid–liquid phase separation and solidification started when the amount of DCM was higher than PEG 400 for 2.67 folds and DCM amount was equal to that of PEG 400, respectively. These results could clarify the pore formation mechanism of porous PLA membrane and will be useful for the further investigation and application. - Highlights: • Pore formation mechanism of PLA matrix membrane inducing by PEG 400 addition was investigated. • Cryo-scanning electron microscopy revealed the embedded PEG 400 in matrix membrane. • Tracking of structural change during membrane formation with stereomicroscope and thermogravimetric analysis could explain the pore formation mechanism. • Liquid-liquid phase separation of PLA-PEG 400 solution started when the amount of dichloromethane remained 2

  10. Pore formation mechanism of porous poly(DL-lactic acid) matrix membrane

    International Nuclear Information System (INIS)

    Phaechamud, Thawatchai; Chitrattha, Sasiprapa

    2016-01-01

    Porous PLA structure has been widely used in cell transplantation, drug carrier and wound dressing. The porous structure can be controlled depending on the choice of the polymer, solvent, nonsolvent and preparation parameters. In this study, the porous PLA matrix membranes were prepared by adding PEG 400 in PLA solution using dichloromethane (DCM) as solvent prior to casting. The influence of other liquids as co-solvent on pore formation and the structural change during membrane formation were evaluated. The co-solvents affected both porous topography and mechanical properties of PLA membrane. The porous matrix were produced when the non-solvent of PLA was used as co-solvent. Cryo-SEM micrographs revealed that PEG 400 still remained in the PLA porous matrix membrane. From the tracking of the structural change during film formation, the PLA–PEG solution changed into porous structure by liquid liquid phase separation and solidification processes, respectively. Thermogravimetric analysis revealed that PLA–PEG in DCM solution exhibited the two-step of weight loss, the first step occurred from DCM evaporation and the second step occurred from the degradation of PLA–PEG matrix. The liquid–liquid phase separation and solidification started when the amount of DCM was higher than PEG 400 for 2.67 folds and DCM amount was equal to that of PEG 400, respectively. These results could clarify the pore formation mechanism of porous PLA membrane and will be useful for the further investigation and application. - Highlights: • Pore formation mechanism of PLA matrix membrane inducing by PEG 400 addition was investigated. • Cryo-scanning electron microscopy revealed the embedded PEG 400 in matrix membrane. • Tracking of structural change during membrane formation with stereomicroscope and thermogravimetric analysis could explain the pore formation mechanism. • Liquid-liquid phase separation of PLA-PEG 400 solution started when the amount of dichloromethane remained 2

  11. DBDA as a Novel Matrix for the Analyses of Small Molecules and Quantification of Fatty Acids by Negative Ion MALDI-TOF MS

    Science.gov (United States)

    Ling, Ling; Li, Ying; Wang, Sheng; Guo, Liming; Xiao, Chunsheng; Chen, Xuesi; Guo, Xinhua

    2018-01-01

    Matrix interference ions in low mass range has always been a concern when using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to analyze small molecules (fatty acids without matrix interference appeared in the mass spectra and the limit of detection (LOD) reached 0.3 fmol. DBDA also has great performance towards other small molecules such as amino acids, peptides, and nucleotide. Furthermore, with this novel matrix, the free fatty acids in serum were quantitatively analyzed based on the correlation curves with correlation coefficient of 0.99. In addition, UV-Vis experiments and molecular orbital calculations were performed to explore mechanism about DBDA used as matrix in the negative ion mode. The present work shows that the DBDA matrix is a highly sensitive matrix with few interference ions for analysis of small molecules. Meanwhile, DBDA is able to precisely quantify the fatty acids in real biological samples. [Figure not available: see fulltext.

  12. Negative Ion In-Source Decay Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry for Sequencing Acidic Peptides

    Science.gov (United States)

    McMillen, Chelsea L.; Wright, Patience M.; Cassady, Carolyn J.

    2016-05-01

    Matrix-assisted laser desorption/ionization (MALDI) in-source decay was studied in the negative ion mode on deprotonated peptides to determine its usefulness for obtaining extensive sequence information for acidic peptides. Eight biological acidic peptides, ranging in size from 11 to 33 residues, were studied by negative ion mode ISD (nISD). The matrices 2,5-dihydroxybenzoic acid, 2-aminobenzoic acid, 2-aminobenzamide, 1,5-diaminonaphthalene, 5-amino-1-naphthol, 3-aminoquinoline, and 9-aminoacridine were used with each peptide. Optimal fragmentation was produced with 1,5-diaminonphthalene (DAN), and extensive sequence informative fragmentation was observed for every peptide except hirudin(54-65). Cleavage at the N-Cα bond of the peptide backbone, producing c' and z' ions, was dominant for all peptides. Cleavage of the N-Cα bond N-terminal to proline residues was not observed. The formation of c and z ions is also found in electron transfer dissociation (ETD), electron capture dissociation (ECD), and positive ion mode ISD, which are considered to be radical-driven techniques. Oxidized insulin chain A, which has four highly acidic oxidized cysteine residues, had less extensive fragmentation. This peptide also exhibited the only charged localized fragmentation, with more pronounced product ion formation adjacent to the highly acidic residues. In addition, spectra were obtained by positive ion mode ISD for each protonated peptide; more sequence informative fragmentation was observed via nISD for all peptides. Three of the peptides studied had no product ion formation in ISD, but extensive sequence informative fragmentation was found in their nISD spectra. The results of this study indicate that nISD can be used to readily obtain sequence information for acidic peptides.

  13. 18{beta}-Glycyrrhetinic acid inhibits adipogenic differentiation and stimulates lipolysis

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Myung-Hee; Jeong, Jae-Kyo; Lee, You-Jin; Seol, Jae-Won; Ahn, Dong-Choon; Kim, In-Shik [Center for Healthcare Technology Development, Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Jeonju, Jeonbuk 561-756 (Korea, Republic of); Park, Sang-Youel, E-mail: sypark@chonbuk.ac.kr [Center for Healthcare Technology Development, Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Jeonju, Jeonbuk 561-756 (Korea, Republic of)

    2012-04-20

    Highlights: Black-Right-Pointing-Pointer 18{beta}-GA inhibits adipogenic differentiation in 3T3-L1 preadipocytes and stimulates lipolysis in differentiated adipocytes. Black-Right-Pointing-Pointer Anti-adipogenic effect of 18{beta}-GA is caused by down-regulation of PPAR{gamma} and inactivation of Akt signalling. Black-Right-Pointing-Pointer Lipolytic effect of 18{beta}-GA is mediated by up-regulation of HSL, ATGL and perilipin and activation of HSL. -- Abstract: 18{beta}-Glycyrrhetinic acid (18{beta}-GA) obtained from the herb liquorice has various pharmacological properties including anti-inflammatory and anti-bacterial activities. However, potential biological anti-obesity activities are unclear. In this study, novel biological activities of 18{beta}-GA in the adipogenesis of 3T3-L1 preadipocytes and in lipolysis of differentiated adipocytes were identified. Mouse 3T3-L1 cells were used as an in vitro model of adipogenesis and lipolysis, using a mixture of insulin/dexamethasone/3-isobutyl-1-methylxanthine (IBMX) to induce differentiation. The amount of lipid droplet accumulation was determined by an AdipoRed assay. The expression of several adipogenic transcription factors and enzymes was investigated using real-time reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blotting. 18{beta}-GA dose-dependently (1-40 {mu}M) significantly decreased lipid accumulation in maturing preadipocytes. In 3T3-L1 preadipocytes, 10 {mu}M of 18{beta}-GA down-regulated the transcriptional levels of the peroxisome proliferator-activated receptor {gamma}, CCAAT/enhancer-binding protein {alpha} and adiponectin, which are markers of adipogenic differentiation via Akt phosphorylation. Also, in differentiated adipocytes, 18{beta}-GA increased the level of glycerol release and up-regulated the mRNA of hormone-sensitive lipase, adipose TG lipase and perilipin, as well as the phosphorylation of hormone-sensitive lipase at Serine 563. The results indicate that 18{beta

  14. Symbiosis revisited: phosphorus and acid buffering stimulate N2 fixation but not Sphagnum growth

    Science.gov (United States)

    van den Elzen, Eva; Kox, Martine A. R.; Harpenslager, Sarah F.; Hensgens, Geert; Fritz, Christian; Jetten, Mike S. M.; Ettwig, Katharina F.; Lamers, Leon P. M.

    2017-03-01

    In pristine Sphagnum-dominated peatlands, (di)nitrogen (N2) fixing (diazotrophic) microbial communities associated with Sphagnum mosses contribute substantially to the total nitrogen input, increasing carbon sequestration. The rates of symbiotic nitrogen fixation reported for Sphagnum peatlands, are, however, highly variable, and experimental work on regulating factors that can mechanistically explain this variation is largely lacking. For two common fen species (Sphagnum palustre and S. squarrosum) from a high nitrogen deposition area (25 kg N ha-1 yr-1), we found that diazotrophic activity (as measured by 15 - 15N2 labeling) was still present at a rate of 40 nmol N gDW-1 h-1. This was surprising, given that nitrogen fixation is a costly process. We tested the effects of phosphorus availability and buffering capacity by bicarbonate-rich water, mimicking a field situation in fens with stronger groundwater or surface water influence, as potential regulators of nitrogen fixation rates and Sphagnum performance. We expected that the addition of phosphorus, being a limiting nutrient, would stimulate both diazotrophic activity and Sphagnum growth. We indeed found that nitrogen fixation rates were doubled. Plant performance, in contrast, did not increase. Raised bicarbonate levels also enhanced nitrogen fixation, but had a strong negative impact on Sphagnum performance. These results explain the higher nitrogen fixation rates reported for minerotrophic and more nutrient-rich peatlands. In addition, nitrogen fixation was found to strongly depend on light, with rates 10 times higher in light conditions suggesting high reliance on phototrophic organisms for carbon. The contrasting effects of phosphorus and bicarbonate on Sphagnum spp. and their diazotrophic communities reveal strong differences in the optimal niche for both partners with respect to conditions and resources. This suggests a trade-off for the symbiosis of nitrogen fixing microorganisms with their Sphagnum

  15. Combined nitrogen limitation and cadmium stress stimulate total carbohydrates, lipids, protein and amino acid accumulation in Chlorella vulgaris (Trebouxiophyceae).

    Science.gov (United States)

    Chia, Mathias Ahii; Lombardi, Ana Teresa; da Graça Gama Melão, Maria; Parrish, Christopher C

    2015-03-01

    Metals have interactive effects on the uptake and metabolism of nutrients in microalgae. However, the effect of trace metal toxicity on amino acid composition of Chlorella vulgaris as a function of varying nitrogen concentrations is not known. In this research, C. vulgaris was used to investigate the influence of cadmium (10(-7) and 2.0×10(-8)molL(-1) Cd) under varying nitrogen (2.9×10(-6), 1.1×10(-5) and 1.1×10(-3)molL(-1)N) concentrations on its growth rate, biomass and biochemical composition. Total carbohydrates, total proteins, total lipids, as well as individual amino acid proportions were determined. The combination of Cd stress and N limitation significantly inhibited growth rate and cell density of C. vulgaris. However, increasing N limitation and Cd stress stimulated higher dry weight and chlorophyll a production per cell. Furthermore, biomolecules like total proteins, carbohydrates and lipids increased with increasing N limitation and Cd stress. Ketogenic and glucogenic amino acids were accumulated under the stress conditions investigated in the present study. Amino acids involved in metal chelation like proline, histidine and glutamine were significantly increased after exposure to combined Cd stress and N limitation. We conclude that N limitation and Cd stress affects the physiology of C. vulgaris by not only decreasing its growth but also stimulating biomolecule production. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Investigating the use of coupling agents to improve the interfacial properties between a resorbable phosphate glass and polylactic acid matrix.

    Science.gov (United States)

    Hasan, Muhammad Sami; Ahmed, Ifty; Parsons, Andrew J; Rudd, Chris D; Walker, Gavin S; Scotchford, Colin A

    2013-09-01

    Eight different chemicals were investigated as potential candidate coupling agents for phosphate glass fibre reinforced polylactic acid composites. Evidence of reaction of the coupling agents with phosphate glass and their effect on surface wettability and glass degradation were studied along with their principle role of improving the interface between glass reinforcement and polymer matrix. It was found that, with an optimal amount of coupling agent on the surface of the glass/polymer, interfacial shear strength improved by a factor of 5. Evidence of covalent bonding between agent and glass was found for three of the coupling agents investigated, namely: 3-aminopropyltriethoxysilane; etidronic acid and hexamethylene diisocyanate. These three coupling agents also improved the interfacial shear strength and increased the hydrophobicity of the glass surface. It is expected that this would provide an improvement in the macroscopic properties of full-scale composites fabricated from the same materials which may also help to retain these properties for the desired length of time by retarding the breakdown of the fibre/matrix interface within these composites.

  17. Infrared matrix isolation and ab initio studies on isothiocyanic acid HNCS and its complexes with nitrogen and xenon

    International Nuclear Information System (INIS)

    Wierzejewska, Maria; Wieczorek, Robert

    2003-01-01

    The isothiocyanic acid HNCS (DNCS) and its complexes with nitrogen and xenon have been studied experimentally by FTIR matrix isolation technique and computationally with the use of ab initio calculations at the MP2 level. The spectra show that HNCS (DNCS) interacts specifically with nitrogen forming 1:1 hydrogen bonded complex in argon matrix while non-hydrogen bonded structure is probably formed in solid xenon. Two stable minima were localized on the potential energy surface. One of them involves an almost linear hydrogen bond from NH group of the acid molecule to nitrogen molecule lone pair (structure I) and has an interaction energy ΔE CP equal to -6.85 kJ/mol. The second structure (II) where the nitrogen molecule interacts with the sulfur atom of the HNCS was found to be weaker bound and is characterized by ΔE CP =-1.99 kJ/mol. A low energetic barrier of 5.86 kJ/mol between the structures I and II was found. Both experimental and theoretical results obtained for the Xe···HNCS system point to a structure with the NH group interacting with the xenon atom. An interaction energy ΔE CP for this complex is equal to -3.64 kJ/mol

  18. Glucagon-like peptide 2 stimulates glucagon secretion, enhances lipid absorption, and inhibits gastric acid secretion in humans

    DEFF Research Database (Denmark)

    Meier, Juris J; Nauck, Michael A; Pott, Andrea

    2006-01-01

    or placebo during the ingestion of a solid test meal. Gastric emptying was determined using a 13C-sodium-octanote breath test. Plasma concentrations of glucose, insulin, C-peptide, glucagon, GLP-2, free fatty acids, free glycerol, and triglycerides were determined. RESULTS: GLP-2 administration led...... (P = .07). GLP-2 administration caused an approximately 15% reduction in pentagastrin-stimulated gastric acid and chloride secretion (P gastric emptying was not affected (P = .99). CONCLUSIONS: GLP-2 reduces gastric acid secretion but does not seem to have an influence on gastric......BACKGROUND & AIMS: The gut-derived peptide glucagon-like peptide 2 (GLP-2) has been suggested as a potential drug candidate for the treatment of various intestinal diseases. However, the acute effects of GLP-2 on gastric functions as well as on glucose and lipid homeostasis in humans are less well...

  19. Combined nitrogen limitation and cadmium stress stimulate total carbohydrates, lipids, protein and amino acid accumulation in Chlorella vulgaris (Trebouxiophyceae)

    Energy Technology Data Exchange (ETDEWEB)

    Chia, Mathias Ahii, E-mail: chia28us@yahoo.com [Department of Botany, Federal University of São Carlos, Rodovia Washington Luis km 235, São Carlos, SP Cep 13565905 (Brazil); Lombardi, Ana Teresa [Department of Botany, Federal University of São Carlos, Rodovia Washington Luis km 235, São Carlos, SP Cep 13565905 (Brazil); Graça Gama Melão, Maria da [Department of Hydrobiology, Federal University of São Carlos, Rodovia Washington Luis km 235, São Carlos, SP Cep 13565905 (Brazil); Parrish, Christopher C. [Department of Ocean Sciences, Memorial University of Newfoundland, St. John’s, Newfoundland A1C 5S7 (Canada)

    2015-03-15

    Highlights: • Chlorella vulgaris was exposed to Cd under varying N concentrations. • Growth rate and cell density decreased with increasing Cd stress and N limitation. • Dry weight, chlorophyll a, total lipid, carbohydrate and protein were accumulated. • Amino acids like proline and glutamine were accumulated under N and Cd stress. • Changes in amino acid composition are sensitive biomarkers for Cd and N stress. - Abstract: Metals have interactive effects on the uptake and metabolism of nutrients in microalgae. However, the effect of trace metal toxicity on amino acid composition of Chlorella vulgaris as a function of varying nitrogen concentrations is not known. In this research, C. vulgaris was used to investigate the influence of cadmium (10{sup −7} and 2.0 × 10{sup −8} mol L{sup −1} Cd) under varying nitrogen (2.9 × 10{sup −6}, 1.1 × 10{sup −5} and 1.1 × 10{sup −3} mol L{sup −1} N) concentrations on its growth rate, biomass and biochemical composition. Total carbohydrates, total proteins, total lipids, as well as individual amino acid proportions were determined. The combination of Cd stress and N limitation significantly inhibited growth rate and cell density of C. vulgaris. However, increasing N limitation and Cd stress stimulated higher dry weight and chlorophyll a production per cell. Furthermore, biomolecules like total proteins, carbohydrates and lipids increased with increasing N limitation and Cd stress. Ketogenic and glucogenic amino acids were accumulated under the stress conditions investigated in the present study. Amino acids involved in metal chelation like proline, histidine and glutamine were significantly increased after exposure to combined Cd stress and N limitation. We conclude that N limitation and Cd stress affects the physiology of C. vulgaris by not only decreasing its growth but also stimulating biomolecule production.

  20. Kynurenic Acid Inhibits the Electrical Stimulation Induced Elevated Pituitary Adenylate Cyclase-Activating Polypeptide Expression in the TNC

    Directory of Open Access Journals (Sweden)

    Tamás Körtési

    2018-01-01

    Full Text Available BackgroundMigraine is a primary headache of imprecisely known mechanism, but activation of the trigeminovascular system (TS appears to be essential during the attack. Intensive research has recently focused on pituitary adenylate cyclase-activating polypeptide (PACAP and the kynurenine systems as potential pathogenic factors.AimWe investigated the link between these important mediators and the effects of kynurenic acid (KYNA and its synthetic analog (KYNA-a on PACAP expression in the rat trigeminal nucleus caudalis (TNC in a TS stimulation model related to migraine mechanisms.MethodsAdult male Sprague-Dawley rats were pretreated with KYNA, KYNA-a, the NMDA receptor antagonist MK-801, or saline (vehicle. Next, the trigeminal ganglion (TRG was electrically stimulated, the animals were transcardially perfused following 180 min, and the TNC was removed. In the TNC samples, 38 amino acid form of PACAP (PACAP1–38-like radioimmunoactivity was measured by radioimmunoassay, the relative optical density of preproPACAP was assessed by Western blot analysis, and PACAP1–38 mRNA was detected by real-time PCR.Results and conclusionElectrical TRG stimulation resulted in significant increases of PACAP1–38-LI, preproPACAP, and PACAP1–38 mRNA in the TNC. These increases were prevented by the pretreatments with KYNA, KYNA-a, and MK-801. This is the first study to provide evidence for a direct link between PACAP and the kynurenine system during TS activation.

  1. Molecularly imprinted polymer-matrix nanocomposite for enantioselective electrochemical sensing of D- and L-aspartic acid

    International Nuclear Information System (INIS)

    Prasad, Bhim Bali; Srivastava, Amrita; Tiwari, Mahavir Prasad

    2013-01-01

    A new molecularly imprinted polymer-matrix (titanium dioxide nanoparticle/multiwalled carbon nanotubes) nanocomposite was developed for the modification of pencil graphite electrode as an enantioselective sensing probe for aspartic acid isomers, prevalent at ultra trace level in aqueous and real samples. The nanocomposite having many shape complementary cavities was synthesized adopting surface initiated-activators regenerated by electron transfer for atom transfer radical polymerization. The proposed sensor has high stability, nanocomposite uniformity, good reproducibility, and enhanced electrocatalytic activity to respond oxidative peak current of L-aspartic acid quantitatively by differential pulse anodic stripping voltammetry, without any cross-reactivity in real samples. Under the optimized operating conditions, the L-aspartic acid imprinted modified electrode showed a wide linear response for L-aspartic acid within the concentration range 9.98–532.72 ng mL −1 , with the minimum detection limit of 1.73–1.79 ng mL −1 (S/N = 3) in aqueous and real samples. Almost similar stringent limit (1.79 ng mL −1 ) was obtained with cerebrospinal fluid which is typical for the primitive diagnosis of neurological disorders, caused by an acute depletion of L-aspartic acid biomarker, in clinical settings. Highlights: • We have adopted surface initiated-activators regenerated by electron transfer for atom transfer radical polymerization. • This approach takes advantage of the nanostructured ultrathin imprinted film. • Successful enantioselective sensing and ultratrace analysis of D- and L-aspartic acid. • Stringent detection limit without any non-specific false-positive contribution

  2. Molecularly imprinted polymer-matrix nanocomposite for enantioselective electrochemical sensing of D- and L-aspartic acid

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, Bhim Bali, E-mail: prof.bbpd@yahoo.com; Srivastava, Amrita; Tiwari, Mahavir Prasad

    2013-10-15

    A new molecularly imprinted polymer-matrix (titanium dioxide nanoparticle/multiwalled carbon nanotubes) nanocomposite was developed for the modification of pencil graphite electrode as an enantioselective sensing probe for aspartic acid isomers, prevalent at ultra trace level in aqueous and real samples. The nanocomposite having many shape complementary cavities was synthesized adopting surface initiated-activators regenerated by electron transfer for atom transfer radical polymerization. The proposed sensor has high stability, nanocomposite uniformity, good reproducibility, and enhanced electrocatalytic activity to respond oxidative peak current of L-aspartic acid quantitatively by differential pulse anodic stripping voltammetry, without any cross-reactivity in real samples. Under the optimized operating conditions, the L-aspartic acid imprinted modified electrode showed a wide linear response for L-aspartic acid within the concentration range 9.98–532.72 ng mL{sup −1}, with the minimum detection limit of 1.73–1.79 ng mL{sup −1} (S/N = 3) in aqueous and real samples. Almost similar stringent limit (1.79 ng mL{sup −1}) was obtained with cerebrospinal fluid which is typical for the primitive diagnosis of neurological disorders, caused by an acute depletion of L-aspartic acid biomarker, in clinical settings. Highlights: • We have adopted surface initiated-activators regenerated by electron transfer for atom transfer radical polymerization. • This approach takes advantage of the nanostructured ultrathin imprinted film. • Successful enantioselective sensing and ultratrace analysis of D- and L-aspartic acid. • Stringent detection limit without any non-specific false-positive contribution.

  3. Anti-Inflammatory Effect of Myristicin on RAW 264.7 Macrophages Stimulated with Polyinosinic-Polycytidylic Acid

    Directory of Open Access Journals (Sweden)

    Wansu Park

    2011-08-01

    Full Text Available Myristicin (1-allyl-5-methoxy-3,4-methylenedioxybenzene is an active aromatic compound found in nutmeg (the seed of Myristica fragrans, carrot, basil, cinnamon, and parsley. Myristicin has been known to have anti-cholinergic, antibacterial, and hepatoprotective effects, however, the effects of myristicin on virus-stimulated macrophages are not fully reported. In this study, the anti-inflammatory effect of myristicin on double-stranded RNA (dsRNA-stimulated macrophages was examined. Myristicin did not reduce the cell viability of RAW 264.7 mouse macrophages at concentrations of up to 50 µM. Myristicin significantly inhibited the production of calcium, nitric oxide (NO, interleukin (IL-6, IL-10, interferon inducible protein-10, monocyte chemotactic protein (MCP-1, MCP-3, granulocyte-macrophage colony-stimulating factor, macrophage inflammatory protein (MIP-1α, MIP-1β, and leukemia inhibitory factor in dsRNA [polyinosinic-polycytidylic acid]-induced RAW 264.7 cells (P < 0.05. In conclusion, myristicin has anti-inflammatory properties related with its inhibition of NO, cytokines, chemokines, and growth factors in dsRNA-stimulated macrophages via the calcium pathway.

  4. Biophysical stimulation improves clinical results of matrix-assisted autologous chondrocyte implantation in the treatment of chondral lesions of the knee.

    Science.gov (United States)

    Collarile, Marco; Sambri, Andrea; Lullini, Giada; Cadossi, Matteo; Zorzi, Claudio

    2018-04-01

    The purpose of the present study was to evaluate the effects of pulsed electromagnetic fields (PEMFs) on clinical outcome in patients who underwent arthroscopic matrix-assisted autologous chondrocyte implantation (MACI) for chondral lesions of the knee. Thirty patients affected by grade III and IV International Cartilage Repair Society chondral lesions of the knee underwent MACI. After surgery, patients were randomly assigned to either experimental group (PEMFs 4 h per day for 60 days) or control group . Clinical outcome was evaluated through International Knee Documentation Committee (IKDC) subjective knee evaluation form, Visual Analog Scale, Short Form-36 (SF-36) and EuroQoL before surgery and 1, 2, 6, and 60 months postoperative. Mean size of chondral lesion was 2.4 ± 0.6 cm 2 in the PEMFs group and 2.5 ± 0.5 cm 2 in the control one. No differences were found between groups at baseline. IKDC score increased in both groups till 6 months, but afterward improvement was observed only in the experimental group with a significant difference between groups at 60 months (p = 0.001). A significant difference between groups was recorded at 60 months for SF-36 (p = 0.006) and EuroQol (p = 0.020). A significant pain reduction was observed in the experimental group at 1-, 2- and 60-month follow-up. Biophysical stimulation with PEMFs improves clinical outcome after arthroscopic MACI for chondral lesions of the knee in the short- and long-term follow-up. Biophysical stimulation should be considered as an effective tool in order to ameliorate clinical results of regenerative medicine. The use of PEMFs represents an innovative therapeutic approach for the survival of cartilage-engineered constructs and consequently the success of orthopaedic surgery. II.

  5. Local effect of zoledronic acid on new bone formation in posterolateral spinal fusion with demineralized bone matrix in a murine model.

    Science.gov (United States)

    Zwolak, Pawel; Farei-Campagna, Jan; Jentzsch, Thorsten; von Rechenberg, Brigitte; Werner, Clément M

    2018-01-01

    Posterolateral spinal fusion is a common orthopaedic surgery performed to treat degenerative and traumatic deformities of the spinal column. In posteriolateral spinal fusion, different osteoinductive demineralized bone matrix products have been previously investigated. We evaluated the effect of locally applied zoledronic acid in combination with commercially available demineralized bone matrix putty on new bone formation in posterolateral spinal fusion in a murine in vivo model. A posterolateral sacral spine fusion in murine model was used to evaluate the new bone formation. We used the sacral spine fusion model to model the clinical situation in which a bone graft or demineralized bone matrix is applied after dorsal instrumentation of the spine. In our study, group 1 received decortications only (n = 10), group 2 received decortication, and absorbable collagen sponge carrier, group 3 received decortication and absorbable collagen sponge carrier with zoledronic acid in dose 10 µg, group 4 received demineralized bone matrix putty (DBM putty) plus decortication (n = 10), and group 5 received DBM putty, decortication and locally applied zoledronic acid in dose 10 µg. Imaging was performed using MicroCT for new bone formation assessment. Also, murine spines were harvested for histopathological analysis 10 weeks after surgery. The surgery performed through midline posterior approach was reproducible. In group with decortication alone there was no new bone formation. Application of demineralized bone matrix putty alone produced new bone formation which bridged the S1-S4 laminae. Local application of zoledronic acid to demineralized bone matrix putty resulted in significant increase of new bone formation as compared to demineralized bone matrix putty group alone. A single local application of zoledronic acid with DBM putty during posterolateral fusion in sacral murine spine model increased significantly new bone formation in situ in our model. Therefore, our

  6. Docosahexaenoic acid inhibits IL-6 expression via PPARγ-mediated expression of catalase in cerulein-stimulated pancreatic acinar cells.

    Science.gov (United States)

    Song, Eun Ah; Lim, Joo Weon; Kim, Hyeyoung

    2017-07-01

    Cerulein pancreatitis mirrors human acute pancreatitis. In pancreatic acinar cells exposed to cerulein, reactive oxygen species (ROS) mediate inflammatory signaling by Janus kinase (JAK) 2/signal transducer and activator of transcription (STAT) 3, and cytokine induction. Docosahexaenoic acid (DHA) acts as an agonist of peroxisome proliferator activated receptor γ (PPARγ), which mediates the expression of some antioxidant enzymes. We hypothesized that DHA may induce PPARγ-target catalase expression and reduce ROS levels, leading to the inhibition of JAK2/STAT3 activation and IL-6 expression in cerulein-stimulated acinar cells. Pancreatic acinar AR42J cells were treated with DHA in the presence or absence of the PPARγ antagonist GW9662, or treated with the PPARγ agonist troglitazone, and then stimulated with cerulein. Expression of IL-6 and catalase, ROS levels, JAK2/STAT3 activation, and nuclear translocation of PPARγ were assessed. DHA suppressed the increase in ROS, JAK2/STAT3 activation, and IL-6 expression induced nuclear translocation of PPARγ and catalase expression in cerulein-stimulated AR42J cells. Troglitazone inhibited the cerulein-induced increase in ROS and IL-6 expression, but induced catalase expression similar to DHA in AR42J cells. GW9662 abolished the inhibitory effect of DHA on cerulein-induced increase in ROS and IL-6 expression in AR42J cells. DHA-induced expression of catalase was suppressed by GW9662 in cerulein-stimulated AR42J cells. Thus, DHA induces PPARγ activation and catalase expression, which inhibits ROS-mediated activation of JAK2/STAT3 and IL-6 expression in cerulein-stimulated pancreatic acinar cells. Copyright © 2017. Published by Elsevier Ltd.

  7. The altered glucose metabolism in tumor and a tumor acidic microenvironment associated with extracellular matrix metalloproteinase inducer and monocarboxylate transporters

    Science.gov (United States)

    Li, Xiaofeng; Yu, Xiaozhou; Dai, Dong; Song, Xiuyu; Xu, Wengui

    2016-01-01

    Extracellular matrix metalloproteinase inducer, also knowns as cluster of differentiation 147 (CD147) or basigin, is a widely distributed cell surface glycoprotein that is involved in numerous physiological and pathological functions, especially in tumor invasion and metastasis. Monocarboxylate transporters (MCTs) catalyze the proton-linked transport of monocarboxylates such as L-lactate across the plasma membrane to preserve the intracellular pH and maintain cell homeostasis. As a chaperone to some MCT isoforms, CD147 overexpression significantly contributes to the metabolic transformation of tumor. This overexpression is characterized by accelerated aerobic glycolysis and lactate efflux, and it eventually provides the tumor cells with a metabolic advantage and an invasive phenotype in the acidic tumor microenvironment. This review highlights the roles of CD147 and MCTs in tumor cell metabolism and the associated molecular mechanisms. The regulation of CD147 and MCTs may prove to be with a therapeutic potential for tumors through the metabolic modification of the tumor microenvironment. PMID:27009812

  8. Towards Acid-Tolerated Ethanol Dehydration: Chitosan-Based Mixed Matrix Membranes Containing Cyano-Bridged Coordination Polymer Nanoparticles.

    Science.gov (United States)

    Wu, C-W; Kang, Chao-Hsiang; Lin, Yi-Feng; Tung, Kuo-Lun; Deng, Yu-Heng; Ahamad, Tansir; Alshehri, Saad M; Suzuki, Norihiro; Yamauchi, Yusuke

    2016-04-01

    Prussian blue (PB) nanoparticles, one of many cyano-bridged coordination polymers, are successfully incorporated into chitosan (CS) polymer to prepare PB/CS mixed matrix membranes (MMMs). The PB nanoparticles are uniformly distributed in the MMMs without the collapse of the original PB structure. As-prepared PB/CS MMMs are used for ethanol dehydration at 25 °C in the pervaporation process. The effect of loading PB in CS matrix on pervaporation performance is carefully investigated. The PB/CS membrane with 30 wt% PB loading shows the best performance with a permeate flux of 614 g. m-2 . h-1 and a separation factor of 1472. The pervaporation using our PB/CS membranes exhibits outstanding performance in comparison with the previously reported CS-based membranes and MMMs. Furthermore, the addition of PB allows PB/CS MMMs to be tolerant of acidic environment. The present work demonstrates good pervaporation performance of PB/CS MMMs for the separation of an ethanol/water (90:10 in wt%) solution. Our new system provides an opportunity for dehydration of bioethanol in the future.

  9. In vitro comparison of new bisphosphonic acids and zoledronate effects on human gingival fibroblasts viability, inflammation and matrix turnover.

    Science.gov (United States)

    De Colli, Marianna; Tortorella, Paolo; Marconi, Guya Diletta; Agamennone, Mariangela; Campestre, Cristina; Tauro, Marilena; Cataldi, Amelia; Zara, Susi

    2016-11-01

    Bisphosphonates (BPs) are drugs clinically used in resorptive diseases. It was already proved that some clinically relevant BPs can inhibit a class of enzymes called matrix metalloproteinases (MMPs), required during tissue remodelling. Combining the arylsulfonamide function with the bisphosphonic group, several compounds were synthesized to obtain selective inhibitors of MMPs. The aim of the present study was to compare the effect of zoledronic acid (ZA), the most potent bisphosphonate available as therapy, with new sulfonamide containing BPs in an in vitro model of human gingival fibroblasts (HGFs). Western blot was used to measure procollagen I, β1 integrin MMP-8 and MMP-9, phase contrast and MTT for cell viability; L-lactate-dehydrogenase (LDH) measurement was performed for toxicity evaluation and ELISA for prostaglandin E 2 (PGE 2 ) secretion assessment. When compared with ZA, the treatment with the newly synthesized compounds shows increasing viability, procollagen I expression and decreased expression of β1 integrin in HGFs. Higher levels of released LDH, PGE 2 and MMP-9 expression are recorded in ZA-treated HGFs. Increased levels of MMP-8 are recorded in newly synthesized compounds-treated samples. These findings allowed to conclude that new tested BPs did not affect HGFs viability and adhesion, did not induce cellular toxicity, were not responsible for inflammatory event induction and could preserve the physiological matrix turnover. It could be hypothesized that the new molecules were better tolerated by soft tissues, resulting in lesser side effects.

  10. Influence of gastric inhibitory polypeptide on pentagastrin-stimulated gastric acid secretion in patients with type 2 diabetes and healthy controls

    DEFF Research Database (Denmark)

    Meier, Juris J; Nauck, Michael A; Kask, Bartholomaeus

    2006-01-01

    the experimental periods with placebo or any dose of GIP. The temporal patterns of gastric acid and chloride secretion were similar in patients with type 2 diabetes and healthy controls (P=0.86 and P=0.61, respectively). CONCLUSION: Pentagastrin-stimulated gastric acid secretion is similar in patients with type 2...

  11. The existence of an insulin-stimulated glucose and non-essential but not essential amino acid substrate interaction in diabetic pigs

    NARCIS (Netherlands)

    Koopmans, S.J.; Meulen, van der J.; Wijdenes, J.W.; Corbijn, H.; Dekker, R.A.

    2011-01-01

    Background The generation of energy from glucose is impaired in diabetes and can be compensated by other substrates like fatty acids (Randle cycle). Little information is available on amino acids (AA) as alternative energy-source in diabetes. To study the interaction between insulin-stimulated

  12. Inhibition of gastrin-stimulated gastric acid secretion by medium-chain triglycerides and long-chain triglycerides in healthy young men.

    NARCIS (Netherlands)

    Maas, M.I.M.; Hopman, W.P.M.; Katan, M.B.; Jansen, J.B.M.J.

    1996-01-01

    Long-chain triglycerides inhibit gastric acid secretion, but the effect of medium-chain triglycerides in humans is unknown. We compared the effects of intraduodenally perfused saline, medium-chain and long-chain triglycerides on gastrin-stimulated gastric acid secretion and cholecystokinin release.

  13. Eugenol stimulates lactate accumulation yet inhibits volatile fatty acid production and eliminates coliform bacteria in cattle and swine waste.

    Science.gov (United States)

    Varel, V H; Miller, D L

    2004-01-01

    To determine how eugenol affects fermentation parameters and faecal coliforms in cattle and swine waste slurries stored anaerobically. Waste slurries (faeces:urine:water, 50:35:15) were blended with and without additives and aliquoted to triplicate 1-l flasks. Faecal coliforms were eliminated in cattle and swine waste slurries within 1 or 2 days with additions of eugenol at 10.05 mm (0.15%) and 16.75 mm (0.25%). At these concentrations volatile fatty acids (VFA) were reduced ca 70 and 50% in cattle and swine waste, respectively, over 6-8 weeks. Additionally, in cattle waste, eugenol stimulated the accumulation of lactate (>180 mm) when compared with thymol treatment (20 mm lactate). In swine waste, lactate accumulation did not occur without additives; eugenol and thymol stimulated lactate accumulation to concentrations of 22 and 32 mm, respectively. Eugenol added to cattle waste may be more beneficial than thymol because not only does it effectively control faecal coliforms and odour (VFA production), it also stimulates lactate accumulation. This in turn, causes the pH to drop more rapidly, further inhibiting microbial activity and nutrient emissions. Plant essential oils have the potential to solve some of the environmental problems associated with consolidated animal feeding operations. Thymol and eugenol reduce fermentative activity, thus, have the potential to reduce emissions of greenhouse gases and odour, and curtail transmission of pathogens in cattle and swine wastes.

  14. Endurance exercise and conjugated linoleic acid (CLA supplementation up-regulate CYP17A1 and stimulate testosterone biosynthesis.

    Directory of Open Access Journals (Sweden)

    Rosario Barone

    Full Text Available A new role for fat supplements, in particular conjugated linoleic acid (CLA, has been delineated in steroidogenesis, although the underlying molecular mechanisms have not yet been elucidated. The aims of the present study were to identify the pathway stimulated by CLA supplementation using a cell culture model and to determine whether this same pathway is also stimulated in vivo by CLA supplementation associated with exercise. In vitro, Leydig tumour rat cells (R2C supplemented with different concentrations of CLA exhibited increasing testosterone biosynthesis accompanied by increasing levels of CYP17A1 mRNA and protein. In vivo, trained mice showed an increase in free plasma testosterone and an up-regulation of CYP17A1 mRNA and protein. The effect of training on CYP17A1 expression and testosterone biosynthesis was significantly higher in the trained mice supplemented with CLA compared to the placebo. The results of the present study demonstrated that CLA stimulates testosterone biosynthesis via CYP17A1, and endurance training led to the synthesis of testosterone in vivo by inducing the overexpression of CYP17A1 mRNA and protein in the Leydig cells of the testis. This effect was enhanced by CLA supplementation. Therefore, CLA-associated physical activity may be used for its steroidogenic property in different fields, such as alimentary industry, human reproductive medicine, sport science, and anti-muscle wasting.

  15. Identification of dihydrogambogic acid as a matrix metalloproteinase 1 inhibitor by high-throughput screening

    Directory of Open Access Journals (Sweden)

    Li Y

    2017-12-01

    Full Text Available Yong Li, John J Voorhees, Gary J FisherDepartment of Dermatology, University of Michigan, Ann Arbor, MI, USAType I collagen (COL1 is the predominant structural protein in the skin. COL1 forms densely packed fibrils which are essential for maintaining skin mechanical properties and youthful appearance.1 The enzyme matrix metalloproteinase-1 (MMP1 cleaves COL1 fibrils at a single site.2 Once cleaved by MMP1, COL1 fibrils can be degraded by other proteases. MMP1 expression is elevated during natural aging and chronic sun exposure, ie, photoaging, leading to excessive degradation of COL1.3 This excessive degradation contributes to COL1 deficiency in the skin of the elderly. COL1 deficiency impairs skin structural integrity and appearance.Given the detrimental role of MMP1 in mediating age-associated fragmentation of COL1 fibrils, it would be beneficial to include MMP1 inhibitors in topical antiaging skin care products. Naturally existing substances that are safe for human use, such as botanical extracts, are often used in skin care products. We have utilized highthroughput screening (HTS to identify naturally existing MMP1 inhibitors that could be used for cosmetic purposes.

  16. Mutually stimulating interactions between lactic acid bacteria and Saccharomyces cerevisiae in sourdough fermentation

    NARCIS (Netherlands)

    Sieuwerts, Sander; Bron, Peter A.; Smid, Eddy J.

    2018-01-01

    Interactions between microorganisms are key to their performance in food habitats. Improved understanding of these interactions supports rational improvement of food fermentations. This study aimed at identifying interactions between lactic acid bacteria and yeast during sourdough fermentation.

  17. Maturation of human embryonic stem cell-derived cardiomyocytes (hESC-CMs) in 3D collagen matrix: Effects of niche cell supplementation and mechanical stimulation.

    Science.gov (United States)

    Zhang, W; Kong, C W; Tong, M H; Chooi, W H; Huang, N; Li, R A; Chan, B P

    2017-02-01

    Cardiomyocytes derived from human embryonic stem cells (hESC-CMs) are regarded as a promising source for regenerative medicine, drug testing and disease modeling. Nevertheless, cardiomyocytes are immature in terms of their contractile structure, metabolism and electrophysiological properties. Here, we fabricate cardiac muscle strips by encapsulating hESC-CMs in collagen-based biomaterials. Supplementation of niche cells at 3% to the number of hESC-CMs enhance the maturation of the hESC-CMs in 3D tissue matrix. The benefits of adding mesenchymal stem cells (MSCs) are comparable to that of adding fibroblasts. These two cell types demonstrate similar effects in promoting the compaction and cell spreading, as well as expression of maturation markers at both gene and protein levels. Mechanical loading, particularly cyclic stretch, produces engineered cardiac tissues with higher maturity in terms of twitch force, elastic modulus, sarcomere length and molecular signature, when comparing to static stretch or non-stretched controls. The current study demonstrates that the application of niche cells and mechanical stretch both stimulate the maturation of hESC-CMs in 3D architecture. Our results therefore suggest that this 3D model can be used for in vitro cardiac maturation study. Cardiomyocytes derived from human embryonic stem cells (hESC-CMs) are regarded as being a promising source of cells for regenerative medicine, drug testing and disease modeling. Nevertheless, cardiomyocytes are immature in terms of their contractile structure, metabolism and electrophysiological properties. In the current study, we have fabricated cardiac muscle strips by encapsulating hESC-CMs in collagen-based biomaterials and demonstrated that supplementation of mesenchymal niche cells as well as provision of mechanical loading particularly stretching have significantly promoted the maturation of the cardiomyocytes and hence improved the mechanical functional characteristics of the tissue strips

  18. Low pressure process for continuous fiber reinforced polyamic acid resin matrix composite laminates

    Science.gov (United States)

    Druyun, Darleen A. (Inventor); Hou, Tan-Hung (Inventor); Kidder, Paul W. (Inventor); Reddy, Rakasi M. (Inventor); Baucom, Robert M. (Inventor)

    1994-01-01

    A low pressure processor was developed for preparing a well-consolidated polyimide composite laminate. Prepreg plies were formed from unidirectional fibers and a polyamic acid resin solution. Molding stops were placed at the sides of a matched metal die mold. The prepreg plies were cut shorter than the length of the mold in the in-plane lateral direction and were stacked between the molding stops to a height which was higher than the molding stops. The plies were then compressed to the height of the stops and heated to allow the volatiles to escape and to start the imidization reaction. After removing the stops from the mold, the heat was increased and 0 - 500 psi was applied to complete the imidization reaction. The heat and pressure were further increased to form a consolidated polyimide composite laminate.

  19. Artificial cartilage bio-matrix formed of hyaluronic acid and Mg2+-polyphosphate

    Directory of Open Access Journals (Sweden)

    X Wang

    2016-11-01

    Full Text Available Here we show that inorganic polyphosphate (polyP, a polyanionic metabolic regulator consisting of multiple phosphate residues linked by energy-rich phosphoanhydride bonds, is present in the synovial fluid. In a biomimetic approach, to enhance cartilage synthesis and regeneration, we prepared amorphous polyP microparticles with Mg2+ as counterions. The particles were characterised by X-ray diffraction (XRD, energy-dispersive X-ray (EDX and Fourier transformed infrared spectroscopic (FTIR analyses. Similar particles were obtained after addition of Mg2+ ions to a solution containing hyaluronic acid, as a major component of the synovial fluid, and soluble Na-polyP. The viscous paste-like material formed, composed of globular microparticles with diameter of 400 nm, strongly promoted the adhesion of chondrocytes and caused a significant upregulation of the expression of the genes encoding collagen type 3A1, as a marker for chondrocyte differentiation, and SOX9, a transcription factor that regulates chondrocyte differentiation and proliferation. The expression level of the collagen type 3A1 gene was also enhanced by exposure of chondrocytes to synovial fluid that was found to contain polyP with a size of about 80 phosphate residues. This stimulatory effect was abolished after pre-incubation of the synovial fluid with the polyP degrading alkaline phosphatase. We propose a strategy for treatment of joint dysfunctions caused by osteoarthritis based on the application of amorphous Mg2+-polyP microparticles thatprevent calcium crystal formation in the synovial fluid using scavenging Ca2+ ions (Mg2+/Ca2+ exchange and enhance chondrocyte function after binding of the Ca2+-polyP to hyaluronic acid at the cartilage surface.

  20. Eicosapentaenoic acid inhibits TNF-α-induced matrix metalloproteinase-9 expression in human keratinocytes, HaCaT cells

    International Nuclear Information System (INIS)

    Kim, Hyeon Ho; Lee, Youngae; Eun, Hee Chul; Chung, Jin Ho

    2008-01-01

    Eicosapentaenoic acid (EPA) is an omega-3 (ω-3) polyunsaturated fatty acid (PUFA), which has anti-inflammatory and anti-cancer properties. Some reports have demonstrated that EPA inhibits NF-κB activation induced by tumor necrosis factor (TNF)-α or lipopolysaccharide (LPS) in various cells. However, its detailed mode of action is unclear. In this report, we investigated whether EPA inhibits the expression of TNF-α-induced matrix metalloproteinases (MMP)-9 in human immortalized keratinocytes (HaCaT). TNF-α induced MMP-9 expression by NF-κB-dependent pathway. Pretreatment of EPA inhibited TNF-α-induced MMP-9 expression and p65 phosphorylation. However, EPA could not affect IκB-α phosphorylation, nuclear translocation of p65, and DNA binding activity of NF-κB. EPA inhibited TNF-α-induced p65 phosphorylation through p38 and Akt inhibition and this inhibition was IKKα-dependent event. Taken together, we demonstrate that EPA inhibits TNF-α-induced MMP-9 expression through inhibition of p38 and Akt activation

  1. Amino acids supply in culture media is not a limiting factor in the matrix synthesis of engineered cartilage tissue

    Science.gov (United States)

    Ng, K. W.; DeFrancis, J. G.; Kugler, L. E.; Kelly, T.-A. N.; Ho, M. M.; O’Conor, C. J.; Ateshian, G. A.; Hung, C. T.

    2013-01-01

    Summary Increased amino acid supplementation (0.5×, 1.0×, and 5.0× recommended concentrations or additional proline) was hypothesized to increase the collagen content in engineered cartilage. No significant differences were found between groups in matrix content or dynamic modulus. Control constructs possessed the highest compressive Young’s modulus on day 42. On day 42, compared to controls, decreased type II collagen was found with 0.5×, 1.0×, and 5.0× supplementation and significantly increased DNA content found in 1.0× and 5.0×. No effects were observed on these measures with added proline. These results lead us to reject our hypothesis and indicate that the low collagen synthesis in engineered cartilage is not due to a limited supply of amino acids in media but may require a further stimulatory signal. The results of this study also highlight the impact that culture environment can play on the development of engineered cartilage. PMID:17713744

  2. Use of stirred tanks for studying matrix effects caused by inorganic acids, easily ionized elements and organic solvents in inductively coupled plasma atomic emission spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Paredes, Eduardo [Departamento de Quimica Analitica, Nutricion y Bromatologia, University of Alicante, 03080 Alicante (Spain); Maestre, Salvador E. [Departamento de Quimica Analitica, Nutricion y Bromatologia, University of Alicante, 03080 Alicante (Spain); Todoli, Jose L. [Departamento de Quimica Analitica, Nutricion y Bromatologia, University of Alicante, 03080 Alicante (Spain)]. E-mail: jose.todoli@ua.es

    2006-03-15

    A stirred tank was used for the first time to elucidate the mechanism responsible for inductively coupled plasma atomic emission spectroscopy (ICP-AES) matrix effects caused by inorganic, acids and easily ionized elements (EIEs), as well as organic, ethanol and acetic acid, compounds. In order to gradually increase the matrix concentration, a matrix solution was introduced inside a stirred container (tank) initially filled with an aqueous multielement standard. PolyTetraFluoroEthylene (PTFE) tubing was used to deliver the resulting solution to the liquid sample introduction system. Matrix concentration ranged from 0 to 2 mol l{sup -1} in the case of inorganic acids (i.e., nitric, sulfuric, hydrochloric and a mixture of them), from 0 to about 2500 mg l{sup -1} for EIEs (i.e., sodium, calcium and mixtures of both) and from 0% to 15%, w/w for organic compounds. Up to 40-50 different solutions were prepared and measured in a period of time shorter than 6-7 min. This investigation was carried out in terms of emission intensity and tertiary aerosols characteristics. The experimental setup used in the present work allowed to thoroughly study the effect of matrix concentration on analytical signal. Generally speaking, the experiments concerning tertiary aerosol characterization revealed that, in the case of inorganic acids and EIEs, the mechanism responsible for changes in aerosol characteristics was the droplet fission. In contrast, for organic matrices it was found that the interference was caused by a change in both aerosol transport and plasma thermal characteristics. The extent of the interferences caused by organic as well as inorganic compounds was compared for a set of 14 emission lines through a wide range of matrix concentrations. With a stirred tank, it is possible to choose an efficient internal standard for any given matrix composition. The time required to complete this procedure was shorter than 7 min.

  3. Use of stirred tanks for studying matrix effects caused by inorganic acids, easily ionized elements and organic solvents in inductively coupled plasma atomic emission spectrometry

    International Nuclear Information System (INIS)

    Paredes, Eduardo; Maestre, Salvador E.; Todoli, Jose L.

    2006-01-01

    A stirred tank was used for the first time to elucidate the mechanism responsible for inductively coupled plasma atomic emission spectroscopy (ICP-AES) matrix effects caused by inorganic, acids and easily ionized elements (EIEs), as well as organic, ethanol and acetic acid, compounds. In order to gradually increase the matrix concentration, a matrix solution was introduced inside a stirred container (tank) initially filled with an aqueous multielement standard. PolyTetraFluoroEthylene (PTFE) tubing was used to deliver the resulting solution to the liquid sample introduction system. Matrix concentration ranged from 0 to 2 mol l -1 in the case of inorganic acids (i.e., nitric, sulfuric, hydrochloric and a mixture of them), from 0 to about 2500 mg l -1 for EIEs (i.e., sodium, calcium and mixtures of both) and from 0% to 15%, w/w for organic compounds. Up to 40-50 different solutions were prepared and measured in a period of time shorter than 6-7 min. This investigation was carried out in terms of emission intensity and tertiary aerosols characteristics. The experimental setup used in the present work allowed to thoroughly study the effect of matrix concentration on analytical signal. Generally speaking, the experiments concerning tertiary aerosol characterization revealed that, in the case of inorganic acids and EIEs, the mechanism responsible for changes in aerosol characteristics was the droplet fission. In contrast, for organic matrices it was found that the interference was caused by a change in both aerosol transport and plasma thermal characteristics. The extent of the interferences caused by organic as well as inorganic compounds was compared for a set of 14 emission lines through a wide range of matrix concentrations. With a stirred tank, it is possible to choose an efficient internal standard for any given matrix composition. The time required to complete this procedure was shorter than 7 min

  4. Sensory-motor responses to mechanical stimulation of the esophagus after sensitization with acid.

    Science.gov (United States)

    Drewes, Asbjørn-Mohr; Reddy, Hariprasad; Staahl, Camilla; Pedersen, Jan; Funch-Jensen, Peter; Arendt-Nielsen, Lars; Gregersen, Hans

    2005-07-28

    Sensitization most likely plays an important role in chronic pain disorders, and such sensitization can be mimicked by experimental acid perfusion of the esophagus. The current study systematically investigated the sensory and motor responses of the esophagus to controlled mechanical stimuli before and after sensitization. Thirty healthy subjects were included. Distension of the distal esophagus with a balloon was performed before and after perfusion with 0.1 mol/L hydrochloric acid for 30 min. An impedance planimetry system was used to measure cross-sectional area, volume, pressure, and tension during the distensions. A new model allowed evaluation of the phasic contractions by the tension during contractions as a function of the initial muscle length before the contraction (comparable to the Frank-Starling law for the heart). Length-tension diagrams were used to evaluate the muscle tone before and after relaxation of the smooth muscle with butylscopolamine. The sensitization resulted in allodynia and hyperalgesia to the distension volumes, and the degree of sensitization was related to the infused volume of acid. Furthermore, a nearly 50% increase in the evoked referred pain was seen after sensitization. The mechanical analysis demonstrated hyper-reactivity of the esophagus following acid perfusion, with an increased number and force of the phasic contractions, but the muscle tone did not change. Acid perfusion of the esophagus sensitizes the sensory pathways and facilitates secondary contractions. The new model can be used to study abnormal sensory-motor mechanisms in visceral organs.

  5. Quantification and enzyme targets of fatty acid amides from duckweed root exudates involved in the stimulation of denitrification.

    Science.gov (United States)

    Sun, Li; Lu, Yufang; Kronzucker, Herbert J; Shi, Weiming

    2016-07-01

    Fatty acid amides from plant root exudates, such as oleamide and erucamide, have the ability to participate in strong plant-microbe interactions, stimulating nitrogen metabolism in rhizospheric bacteria. However, mechanisms of secretion of such fatty acid amides, and the nature of their stimulatory activities on microbial metabolism, have not been examined. In the present study, collection, pre-treatment, and determination methods of oleamide and erucamide in duckweed root exudates are compared. The detection limits of oleamide and erucamide by gas chromatography (GC) (10.3ngmL(-1) and 16.1ngmL(-1), respectively) are shown to be much lower than those by liquid chromatography (LC) (1.7 and 5.0μgmL(-1), respectively). Quantitative GC analysis yielded five times larger amounts of oleamide and erucamide in root exudates of Spirodela polyrrhiza when using a continuous collection method (50.20±4.32 and 76.79±13.92μgkg(-1) FW day(-1)), compared to static collection (10.88±0.66 and 15.27±0.58μgkg(-1) FW day(-1)). Furthermore, fatty acid amide secretion was significantly enhanced under elevated nitrogen conditions (>300mgL(-1)), and was negatively correlated with the relative growth rate of duckweed. Mechanistic assays were conducted to show that erucamide stimulates nitrogen removal by enhancing denitrification, targeting two key denitrifying enzymes, nitrate and nitrite reductases, in bacteria. Our findings significantly contribute to our understanding of the regulation of nitrogen dynamics by plant root exudates in natural ecosystems. Copyright © 2016 Elsevier GmbH. All rights reserved.

  6. Effects of spray-drying on w/o/w multiple emulsions prepared from a stearic acid matrix

    Directory of Open Access Journals (Sweden)

    Mlalila N

    2014-12-01

    Full Text Available Nichrous Mlalila,1 Hulda Swai,2 Lonji Kalombo,2 Askwar Hilonga3 1School of Life Sciences and Bioengineering, Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania; 2Materials Science and Manufacturing, Council for Scientific and Industrial Research, Pretoria, South Africa; 3Department of Materials Science and Engineering, Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania Abstract: The goal of this study was to explore the effects of spray-drying on w/o/w double emulsions of methyltestosterone (MT loaded in a stearic acid matrix. MT-loaded nanoparticles were formulated by a water-in-oil-in-water emulsion technique using 50, 75, and 100 mg of stearic acid, 2% and 3% w/v polyvinyl alcohol, 5% w/v lactose, and 0.2% w/v chitosan. The emulsions were immediately spray-dried based on an optimized model of inlet temperature and pump rate, and characterized for optimized responses with regard to particle size, polydispersity index, and zeta potential, for both emulsion and powder samples. Dynamic light scattering analysis shown that the nanoparticles increased in size with increasing concentrations of polyvinyl alcohol and stearic acid. Scanning electron microscopy indicated that the MT-loaded nanoparticles were spherical in shape, had a smooth surface, and were in an amorphous state, which was confirmed by differential scanning calorimetry. These MT-loaded nanoparticles are a promising candidate carrier for the delivery of MT; however, further studies are needed in order to establish the stability of the system and the cargo release profile under normal conditions of use. Keywords: double emulsions, nanoparticles, pump rate, spray-drying, testosterone

  7. Sensory-motor responses to mechanical stimulation of the esophagus after sensitization with acid

    OpenAIRE

    Drewes, Asbjorn Mohr; Reddy, Hariprasad; Staahl, Camilla; Pedersen, Jan; Funch-Jensen, Peter; Arendt-Nielsen, Lars; Gregersen, Hans

    2005-01-01

    AIM: Sensitization most likely plays an important role in chronic pain disorders, and such sensitization can be mimicked by experimental acid perfusion of the esophagus. The current study systematically investigated the sensory and motor responses of the esophagus to controlled mechanical stimuli before and after sensitization.

  8. Effect of isoprenaline on pentagastrin-stimulated gastric acid secretion in dogs with gastric fistula

    DEFF Research Database (Denmark)

    Hovendal, C P; Gottrup, F; Bech, K

    1981-01-01

    The purpose of this study was to elucidate the effect of a beta 1-adrenoceptor agonist on gastric acid secretion in conscious dogs with gastric fistula. Isoprenaline, a beta 1- and beta 2-agonist was used alone and in conjunction with selective blockade of beta 2- and beta 1-receptors. Isoprenaline...

  9. To Stimulate or Inhibit? That Is the Question for the Function of Abscisic Acid

    Czech Academy of Sciences Publication Activity Database

    Humplík, Jan; Bergougnoux, V.; Van Volkenburgh, E.

    2017-01-01

    Roč. 22, č. 10 (2017), s. 830-841 ISSN 1360-1385 R&D Projects: GA MŠk(CZ) LO1204 Grant - others:PPPLZ(CZ) L200381651 Institutional support: RVO:61389030 Keywords : abscisic acid * etiolation * hypocotyl * photomorphogenesis * skotomorphogenesis Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Plant sciences, botany Impact factor: 11.911, year: 2016

  10. Humic Acid-Like Material from Sewage Sludge Stimulates Culture Growth of Ectomycorrhizal Fungi in Vitro

    Czech Academy of Sciences Publication Activity Database

    Hršelová, Hana; Soukupová, Lucie; Gryndler, Milan

    2007-01-01

    Roč. 52, č. 6 (2007), s. 627-630 ISSN 0015-5632 R&D Projects: GA ČR GA526/06/0540 Institutional research plan: CEZ:AV0Z50200510 Keywords : ectomycorrhizal basidiomycetes * sewage sludge * humic-acid-like materials Subject RIV: EE - Microbiology, Virology Impact factor: 0.989, year: 2007

  11. Potential Effects of Caffeic Acid in Suppression of Matrix Metalloproteinases Activities in Irradiated Rats

    International Nuclear Information System (INIS)

    Zahran, A.M.

    2008-01-01

    Great Number of researches on the potential role of antioxidant nutrients and phenolic compounds in the prevention of chronic diseases has been accumulated over the past several decades. Despite this effort, there is much that remains uncertain. Bio markers research in this field has the potential to help fill the gaps in current knowledge. The present study was designed to evaluate, in one aspect, the probable direction expression of proteolytic enzymes as indices for gamma-irradiation-induced oxidative stress and their relationship, in other aspect with one antioxidant micro nutrient phenolic compound: caffeic acid (CA). Sprague Dawley male albino rats were administrated CA intraperitoneally (i.p.) 10 μmol/ kg body wt/ day for 8 consecutive days pre irradiation exposure (fractionated doses, instalment as 1 Gy every day up to total dose of 8 Gy). The treatment was continued for 15 successive days following irradiation processing. Quantitative assay of gelatinolytic zymo graphic analysis of serum and hepatic tissues showed that exposure to gamma-rays yields a marked significant increase in the activities of both latent and active MMP-9 (92 and 86 kDa), respectively, and both latent and active MMP-2 (72 and 66 kDa), respectively. Administration of CA significantly decreased the activities of MMP-2 and MMP-9 in gamma-irradiated rats. Conclusion: the present findings demonstrated that irradiation-exposure leads to enhancement of enzymatic activities of MMP-2 and MMP-9 in their inactive and active forms in the serum and liver. Meanwhile, administration of CA exhibits protective effects in gamma-irradiated rats through down-regulation of MMP-2 and MMP-9 activities

  12. Anti-Inflammatory Activity of Citric Acid-Treated Wheat Germ Extract in Lipopolysaccharide-Stimulated Macrophages.

    Science.gov (United States)

    Jeong, Hee-Yeong; Choi, Yong-Seok; Lee, Jae-Kang; Lee, Beom-Joon; Kim, Woo-Ki; Kang, Hee

    2017-07-10

    Until recently, fermentation was the only processing used to improve the functionality of wheat germ. The release of 2,6-dimethoxy-1,4-benzoquinone (DMBQ) from hydroquinone glycosides during the fermentation process is considered a marker of quality control. Here, we treated wheat germ extract with citric acid (CWG) to release DMBQ and examined the anti-inflammatory activity of this extract using a lipopolysaccharide-activated macrophage model. Treatment of wheat germ with citric acid resulted in detectable release of DMBQ but reduced total phenolic and total flavonoid contents compared with untreated wheat germ extract (UWG). CWG inhibited secretion of the pro-inflammatory cytokines tumor necrosis factor-α, interleukin (IL)-6, and IL-12 and the synthesis of cyclooxygenase-2, while UWG only decreased IL-12 production. CWG and UWG induced high levels of anti-inflammatory IL-10 and heme oxygenase-1. CWG specifically inhibited phosphorylation of NF-κB p65 and p38 kinase at 15 min after LPS stimulation. Our study showed that citric acid treatment enhanced the anti-inflammatory activity of wheat germ extract.

  13. Structural Analysis and Immuno-Stimulating Activity of an Acidic Polysaccharide from the Stems of Dendrobium nobile Lindl.

    Science.gov (United States)

    Wang, Jun-Hui; Zuo, Shu-Rong; Luo, Jian-Ping

    2017-04-10

    Dendrobium nobile Lindl., an epiphytic herb distributed in the Southeast Asia, is used as a tonic and antipyretic herbal medicine in China. In this study, a water-soluble acidic heteropolysaccharide, DNP-W4, containing mannose, glucose, galactose, xylose, rhamnose, and galacturonic acid, in the molar ratios of 1.0:4.9:2.5:0.5:1.0:0.9, was obtained from the stems of Dendrobium nobile Lindl. Using methylation analysis, partial acid hydrolysis, pectolyase treatment, NMR, and ESI-MS, the structure of DNP-W4 was elucidated. The obtained data indicated that DNP-W4 was a complex heteropolysaccharide and possessed a backbone composed of (1→4)-linked β-d-Glcp, (1→6)-linked β-d-Glcp, and (1→6)-linked β-d-Galp, with substitutes at O-4/6 of Glcp residues and O-3 of Galp. The branches of DNP-W4 were composed of terminal Manp, (1→6)-linked β-d-Manp, (1→3)-linked β-d-Glcp, β-d-Glcp, β-d-Galp, (1→4)-linked α-d-GalAp, (1→2)-linked α-L-Rhap, and Xylp. DNP-W4 had little immunological activities, but its derivatives had immuno-stimulating activities to some extent.

  14. Study on the Fouling Behavior of Polyethylene and Silica Nanoparticles Mixed Matrix Membranes in Filtration of Humic Acid Solution

    Directory of Open Access Journals (Sweden)

    Ali Akbari

    2016-09-01

    Full Text Available Because most contaminants in water create strong interactions with hydrophobic surfaces, there are usually problems such as flux decline and pore blocking in polyethylene (PE membranes due to irreversible adsorption of foulants on their intrinsic hydrophobic surface. Therefore, in this work, attempts were made to improve the properties of PE membranes in terms of water flux and membrane fouling resistance by dispersion of silica nanoparticles (NPs. First, NPs were synthesized by sol-gel method at two concentrations of ammonia (0.5 and 1 mol/L. The synthesized NPs with smaller size were used to fabricate the mixed matrix PE membranes containing 0, 0.5, 1 and 2 wt% NPs. FE-SEM and EDX analyses were employed to evaluate the morphology and structure of the fabricated membranes and confirmed the presence of NPs in the membranes matrix. The results of pure water flux test revealed that the membrane containing 1 wt% NPs displayed the maximum flux of 30 L/m2.h. Furthermore, the performance and fouling behaviors of membranes during filtration of humic acid solution, one of the most important contaminants of water resources, were studied using a classical fouling model. Fouling mechanism analysis showed that for neat and NPs-embedded membranes containing 0.5 and 2 wt% NPs, the best fit of the data was obtained by cake layer formation as well as the intermediate blocking mechanisms. However, the best fit of the experimental data of NPs-embedded membrane containing 1 wt% occurred with only cake layer formation mechanism. The investigation on membrane fouling resistance showed that 1 wt% NPs-embedded membrane displayed 58% maximum flux recovery and 52% reversibility to total fouling ratio, respectively.

  15. Anti-inflammatory effects of ursodeoxycholic acid by lipopolysaccharide-stimulated inflammatory responses in RAW 264.7 macrophages.

    Directory of Open Access Journals (Sweden)

    Wan-Kyu Ko

    Full Text Available The aim of this study was to investigate the anti-inflammatory effects of Ursodeoxycholic acid (UDCA in lipopolysaccharide (LPS-stimulated RAW 264.7 macrophages.We induced an inflammatory process in RAW 264.7 macrophages using LPS. The anti-inflammatory effects of UDCA on LPS-stimulated RAW 264.7 macrophages were analyzed using nitric oxide (NO. Pro-inflammatory and anti-inflammatory cytokines were analyzed by quantitative real time polymerase chain reaction (qRT-PCR and enzyme-linked immunosorbent assay (ELISA. The phosphorylations of extracellular signal-regulated kinase (ERK, c-Jun N-terminal kinase (JNK, and p38 in mitogen-activated protein kinase (MAPK signaling pathways and nuclear factor kappa-light polypeptide gene enhancer in B-cells inhibitor, alpha (IκBα signaling pathways were evaluated by western blot assays.UDCA decreased the LPS-stimulated release of the inflammatory mediator NO. UDCA also decreased the pro-inflammatory cytokines tumor necrosis factor-α (TNF-α, interleukin 1-α (IL-1α, interleukin 1-β (IL-1β, and interleukin 6 (IL-6 in mRNA and protein levels. In addition, UDCA increased an anti-inflammatory cytokine interleukin 10 (IL-10 in the LPS-stimulated RAW 264.7 macrophages. UDCA inhibited the expression of inflammatory transcription factor nuclear factor kappa B (NF-κB in LPS-stimulated RAW 264.7 macrophages. Furthermore, UDCA suppressed the phosphorylation of ERK, JNK, and p38 signals related to inflammatory pathways. In addition, the phosphorylation of IκBα, the inhibitor of NF-κB, also inhibited by UDCA.UDCA inhibits the pro-inflammatory responses by LPS in RAW 264.7 macrophages. UDCA also suppresses the phosphorylation by LPS on ERK, JNK, and p38 in MAPKs and NF-κB pathway. These results suggest that UDCA can serve as a useful anti-inflammatory drug.

  16. Effect of phosphate-based glass fibre surface properties on thermally produced poly(lactic acid) matrix composites.

    Science.gov (United States)

    Mohammadi, Maziar Shah; Ahmed, Ifty; Muja, Naser; Rudd, Christopher D; Bureau, Martin N; Nazhat, Showan N

    2011-12-01

    Incorporation of soluble bioactive glass fibres into biodegradable polymers is an interesting approach for bone repair and regeneration. However, the glass composition and its surface properties significantly affect the nature of the fibre-matrix interface and composite properties. Herein, the effect of Si and Fe on the surface properties of calcium containing phosphate based glasses (PGs) in the system (50P(2)O(5)-40CaO-(10-x)SiO(2)-xFe(2)O(3), where x = 0, 5 and 10 mol.%) were investigated. Contact angle measurements revealed a higher surface energy, and surface polarity as well as increased hydrophilicity for Si doped PG which may account for the presence of surface hydroxyl groups. Two PG formulations, 50P(2)O(5)-40CaO-10Fe(2)O(3) (Fe10) and 50P(2)O(5)-40CaO-5Fe(2)O(3)-5SiO(2) (Fe5Si5), were melt drawn into fibres and randomly incorporated into poly(lactic acid) (PLA) produced by melt processing. The ageing in deionised water (DW), mechanical property changes in phosphate buffered saline (PBS) and cytocompatibility properties of these composites were investigated. In contrast to Fe10 and as a consequence of the higher surface energy and polarity of Fe5Si5, its incorporation into PLA led to increased inorganic/organic interaction indicated by a reduction in the carbonyl group of the matrix. PLA chain scission was confirmed by a greater reduction in its molecular weight in PLA-Fe5Si5 composites. In DW, the dissolution rate of PLA-Fe5Si5 was significantly higher than that of PLA-Fe10. Dissolution of the glass fibres resulted in the formation of channels within the matrix. Initial flexural strength was significantly increased through PGF incorporation. After PBS ageing, the reduction in mechanical properties was greater for PLA-Fe5Si5 compared to PLA-Fe10. MC3T3-E1 preosteoblasts seeded onto PG discs, PLA and PLA-PGF composites were evaluated for up to 7 days indicating that the materials were generally cytocompatible. In addition, cell alignment along the PGF

  17. The composition of acids in bitumen and in products from saponification of kerogen: Investigation of their role as connecting kerogen and mineral matrix

    Energy Technology Data Exchange (ETDEWEB)

    Razvigorova, M.; Budinova, T.; Tsyntsarski, B.; Petrova, B. [Bulgarian Academy of Sciences, Institute of Organic Chemistry, 1113 Sofia, Acad. Bonchev Str., bl. 9 (Bulgaria); Ekinci, E. [ISIK University, Kumbaba Mevkii, 34980 Istanbul (Turkey); Atakul, H. [Istanbul Technical University, Department of Chemical Engineering, Maslak, 34469 Istanbul (Turkey)

    2008-11-03

    In order to obtain more information and to understand the nature of relation between organic and mineral matter in oil shales, the compositions of soluble bitumen fractions obtained by extraction from Bulgarian oil shales before and after demineralization with 10% HCl, concentrated HF, and a HF/HCl mixture were investigated. The four extracts were quantitatively examined by IR and {sup 1}H NMR spectroscopy. The investigation of isolated acidic material of the bitumen fractions showed that the fatty acids are present in bitumen fractions as free acids, esters and salts. The amount of free acids in bitumen is very small. The dominant part of bitumen acids is associated with mineral components of the oil shales as well as part of them is included in the mineral matrix, and can be separated only after deep demineralization. The kerogen of the oil shales, obtained after separation of the bitumen fractions and mineral components, was subjected to saponification in order to determine the amount of acids, bound as esters to the kerogen matrix. The major components found were n-carboxylic, {alpha},{omega}-di-carboxylic, and aromatic acids. The connection of kerogen with mineral components is accomplished by the participation of carboxylic and complicated ester bonds. Experimental data for the composition of bitumen acids give evidence that algae and terrestrial materials are initial sources in the formation of soluble organic matter of Bulgarian oil shale. (author)

  18. Electrical stimulation promotes nerve cell differentiation on polypyrrole/poly (2-methoxy-5 aniline sulfonic acid) composites.

    Science.gov (United States)

    Liu, Xiao; Gilmore, Kerry J; Moulton, Simon E; Wallace, Gordon G

    2009-12-01

    The purpose of this work was to investigate for the first time the potential biomedical applications of novel polypyrrole (PPy) composites incorporating a large polyelectrolyte dopant, poly (2-methoxy-5 aniline sulfonic acid) (PMAS). The physical and electrochemical properties were characterized. The PPy/PMAS composites were found to be smooth and hydrophilic and have low electrical impedance. We demonstrate that PPy/PMAS supports nerve cell (PC12) differentiation, and that clinically relevant 250 Hz biphasic current pulses delivered via PPy/PMAS films significantly promote nerve cell differentiation in the presence of nerve growth factor (NGF). The capacity of PPy/PMAS composites to support and enhance nerve cell differentiation via electrical stimulation renders them valuable for medical implants for neurological applications.

  19. Chemical stimulation techniques for geothermal wells: experiments on the three-well EGS system at Soultz-sous-Forêts, France

    OpenAIRE

    Portier, Sandrine; Vuataz, François-David; Nami, Patrick; Sanjuan, Bernard; Gérard, André

    2012-01-01

    Rock matrix stimulation is a method of enhancing well production or injection within a broad range of challenging environments, varying from naturally fractured limestones to sandstones with complex mineralogy. A common and often successful stimulation option, matrix acidizing, utilizes acids that react and remove mineral phases restricting fluid flow. Reviewed is the technology of chemical treatments available for oil, gas and geothermal wells and the key elements and results of the chemical...

  20. Gibberellic Acid-Stimulated Arabidopsis6 Serves as an Integrator of Gibberellin, Abscisic Acid, and Glucose Signaling during Seed Germination in Arabidopsis.

    Science.gov (United States)

    Zhong, Chunmei; Xu, Hao; Ye, Siting; Wang, Shiyi; Li, Lingfei; Zhang, Shengchun; Wang, Xiaojing

    2015-11-01

    The DELLA protein REPRESSOR OF ga1-3-LIKE2 (RGL2) plays an important role in seed germination under different conditions through a number of transcription factors. However, the functions of the structural genes associated with RGL2-regulated germination are less defined. Here, we report the role of an Arabidopsis (Arabidopsis thaliana) cell wall-localized protein, Gibberellic Acid-Stimulated Arabidopsis6 (AtGASA6), in functionally linking RGL2 and a cell wall loosening expansin protein (Arabidopsis expansin A1 [AtEXPA1]), resulting in the control of embryonic axis elongation and seed germination. AtGASA6-overexpressing seeds showed precocious germination, whereas transfer DNA and RNA interference mutant seeds displayed delayed seed germination under abscisic acid, paclobutrazol, and glucose (Glc) stress conditions. The differences in germination rates resulted from corresponding variation in cell elongation in the hypocotyl-radicle transition region of the embryonic axis. AtGASA6 was down-regulated by RGL2, GLUCOSE INSENSITIVE2, and ABSCISIC ACID-INSENSITIVE5 genes, and loss of AtGASA6 expression in the gasa6 mutant reversed the insensitivity shown by the rgl2 mutant to paclobutrazol and the gin2 mutant to Glc-induced stress, suggesting that it is involved in regulating both the gibberellin and Glc signaling pathways. Furthermore, it was found that the promotion of seed germination and length of embryonic axis by AtGASA6 resulted from a promotion of cell elongation at the embryonic axis mediated by AtEXPA1. Taken together, the data indicate that AtGASA6 links RGL2 and AtEXPA1 functions and plays a role as an integrator of gibberellin, abscisic acid, and Glc signaling, resulting in the regulation of seed germination through a promotion of cell elongation. © 2015 American Society of Plant Biologists. All Rights Reserved.

  1. Insulin does not stimulate muscle protein synthesis during increased plasma branched-chain amino acids alone but still decreases whole body proteolysis in humans.

    Science.gov (United States)

    Everman, Sarah; Meyer, Christian; Tran, Lee; Hoffman, Nyssa; Carroll, Chad C; Dedmon, William L; Katsanos, Christos S

    2016-10-01

    Insulin stimulates muscle protein synthesis when the levels of total amino acids, or at least the essential amino acids, are at or above their postabsorptive concentrations. Among the essential amino acids, branched-chain amino acids (BCAA) have the primary role in stimulating muscle protein synthesis and are commonly sought alone to stimulate muscle protein synthesis in humans. Fourteen healthy young subjects were studied before and after insulin infusion to examine whether insulin stimulates muscle protein synthesis in relation to the availability of BCAA alone. One half of the subjects were studied in the presence of postabsorptive BCAA concentrations (control) and the other half in the presence of increased plasma BCAA (BCAA). Compared with that prior to the initiation of the insulin infusion, fractional synthesis rate of muscle protein (%/h) did not change (P > 0.05) during insulin in either the control (0.04 ± 0.01 vs 0.05 ± 0.01) or the BCAA (0.05 ± 0.02 vs. 0.05 ± 0.01) experiments. Insulin decreased (P BCAA (0.89 ± 0.07 vs 0.61 ± 0.03) experiments, but the change was not different between the two experiments (P > 0.05). In conclusion, insulin does not stimulate muscle protein synthesis in the presence of increased circulating levels of plasma BCAA alone. Insulin's suppressive effect on proteolysis is observed independently of the levels of circulating plasma BCAA. Copyright © 2016 the American Physiological Society.

  2. Phosphatidic acid accumulation and catecholamine release in adrenal chromaffin cells: stimulation by high potassium and by nicotine, and effect of a diacylglycerol kinase inhibitor R 59 022.

    Science.gov (United States)

    Owen, P J; Jones, J A; Boarder, M R

    1991-09-01

    Using primary cultures of bovine adrenal chromaffin cells labelled with 32Pi, we show that stimulation with bradykinin, nicotine, or a depolarising concentration of potassium stimulates the accumulation of [32P]phosphatidic acid. The effects of nicotine and potassium are smaller than the effect of bradykinin, and are dependent entirely on extracellular calcium. The diacylglycerol kinase inhibitor R 59 022 attenuates the formation of phosphatidic acid by nicotine and depolarising concentrations of potassium. This inhibitor also blocks the nicotine and potassium stimulation of noradrenaline release from chromaffin cells. Using 45Ca2+ influx studies, we show that the nicotine-evoked calcium influx is also attenuated by R 59 022. These observations contrast with those in another report in which we showed that bradykinin stimulation of either [32P]phosphatidic acid accumulation or noradrenaline release is not affected by R 59 022. It is likely that the calcium influx produced by nicotine and depolarising potassium is blocked by R 59 022 by a mechanism that is independent of its ability to block diacylglycerol kinase. The nicotine- and potassium-stimulated [32P]phosphatidic acid accumulation is a consequence of this calcium influx and presumably reflects calcium activation of either phospholipase C or phospholipase D.

  3. Effect of cartilaginous matrix components on the chondrogenesis and hypertrophy of mesenchymal stem cells in hyaluronic acid hydrogels.

    Science.gov (United States)

    Zhu, Meiling; Feng, Qian; Sun, Yuxin; Li, Gang; Bian, Liming

    2017-11-01

    The microenvironment of the extracellular matrix (ECM) plays a key role in directing the viability and subsequent differentiation of the encapsulated stem cells by the specific integration between the hydrated biomolecules and cell surface receptors. Herein, we developed a hydrogel platform based on hyaluronic acid (HA) that presents cartilage ECM molecules as a form of developmental cues. The hybrid hydrogels were generated by coupling photo-cross-linkable methacrylated HA (MeHA) with selected cartilaginous ECM molecules including chondroitin sulfate (CS) and type I collagen (Col I), and we studied the decoupled function of these cues in regulating the initial chondrogenesis, subsequent hypertrophy, and tissue mineralization by hMSCs. The results indicate upregulated mRNA expression of the chondrogenesis markers in the HA hydrogels that contain Col I or CS, and decreased expression of the hypertrophic markers compared with the control MeHA group. The quantification results also show that glycosaminoglycans accumulation increases in the hybrid hydrogels containing cartilaginous ECM molecules, both in vitro and in vivo. We hypothesize that these additional ECM components in the HA hydrogels further regulate the hMSCs chondrogenesis and hypertrophy by coordination. The understanding obtained in this study may guide biomaterial scaffold design, thereby facilitating manipulation of the differentiation and mineralization of induced hMSCs for application in the repair of different musculoskeletal defects. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2292-2300, 2017. © 2016 Wiley Periodicals, Inc.

  4. Evaluation of Influence of Various Polymers on Dissolution and Phase Behavior of Carbamazepine-Succinic Acid Cocrystal in Matrix Tablets

    Directory of Open Access Journals (Sweden)

    Majeed Ullah

    2015-01-01

    Full Text Available The aim of current study was to explore the influence of three commonly used polymers, that is, cellulosics and noncellulosics, for example, Methocel K4M, Kollidon VA/64, and Soluplus, on the phase disproportionation and drug release profile of carbamazepine-succinic acid (CBZ-SUC cocrystal at varying drug to polymer ratios (1 : 1 to 1 : 0.25 in matrix tablets. The polymorphic phase disproportionation during in-depth dissolution studies of CBZ-SUC cocrystals and its crystalline properties were scrutinized by X-ray powder diffractrometry and Raman spectroscopy. The percent drug release from HPMC formulations (CSH showed inverse relation with the concentration of polymer; that is, drug release increased with decrease in polymer concentration. On contrary, direct relation was observed between percent drug release and polymer concentrations of Kollidon VA 64/Soluplus (CSK, CSS. At similar polymer concentration, drug release from pure carbamazepine was slightly lower with HPMC formulations than that of cocrystal; however, opposite trend in release rate was observed with Kollidon VA/64 and Soluplus. The significant increase in dissolution rate of cocrystal occurred with Kollidon VA/64 and Soluplus at higher polymer concentration. Moreover, no phase change took place in Methocel and Kollidon formulations. No tablet residue was left for Soluplus formulation so the impact of polymer on cocrystal integrity cannot be predicted.

  5. Evaluation of Influence of Various Polymers on Dissolution and Phase Behavior of Carbamazepine-Succinic Acid Cocrystal in Matrix Tablets

    Science.gov (United States)

    Ullah, Majeed; Ullah, Hanif; Mahmood, Qaisar; Hussain, Izhar

    2015-01-01

    The aim of current study was to explore the influence of three commonly used polymers, that is, cellulosics and noncellulosics, for example, Methocel K4M, Kollidon VA/64, and Soluplus, on the phase disproportionation and drug release profile of carbamazepine-succinic acid (CBZ-SUC) cocrystal at varying drug to polymer ratios (1 : 1 to 1 : 0.25) in matrix tablets. The polymorphic phase disproportionation during in-depth dissolution studies of CBZ-SUC cocrystals and its crystalline properties were scrutinized by X-ray powder diffractrometry and Raman spectroscopy. The percent drug release from HPMC formulations (CSH) showed inverse relation with the concentration of polymer; that is, drug release increased with decrease in polymer concentration. On contrary, direct relation was observed between percent drug release and polymer concentrations of Kollidon VA 64/Soluplus (CSK, CSS). At similar polymer concentration, drug release from pure carbamazepine was slightly lower with HPMC formulations than that of cocrystal; however, opposite trend in release rate was observed with Kollidon VA/64 and Soluplus. The significant increase in dissolution rate of cocrystal occurred with Kollidon VA/64 and Soluplus at higher polymer concentration. Moreover, no phase change took place in Methocel and Kollidon formulations. No tablet residue was left for Soluplus formulation so the impact of polymer on cocrystal integrity cannot be predicted. PMID:26380301

  6. Treatment of facial atrophic scars with Esthélis, a hyaluronic acid filler with polydense cohesive matrix (CPM).

    Science.gov (United States)

    Hasson, Ariel; Romero, William A

    2010-12-01

    The treatment of atrophic scars is difficult and dermal filler materials provide a simple alternative with immediate results. Esthélis® is an injectable non-animal crosslinked hyaluronic acid of Swiss origin characterized by a polydense cohesive matrix (CPM®) which produces a gel of uniform consistency with better biointegration to the tissues and a longer duration. To evaluate Esthélis in the treatment of atrophic scars. Twelve patients aged 18-56 years with facial atrophic scars caused by acne vulgaris, dog bite, piercing, basal cell carcinoma and leishmaniasis were treated with Esthélis. The injection technique was linear threading, serial puncture or a combination of both. Clinical efficacy was assessed independently by the authors and by patients immediately, one week and one month after the injection. Adverse events were registered. Authors described the results as moderate (27%), good (57%) and excellent (17%), immediately, one week and one month after the injection. Patients evaluated the cosmetic improvement as good (42%) or excellent (58%) one month after the treatment. Pain during the injection was described as slight or moderate. Only mild erythema was observed immediately after injection, which spontaneously resolved within few hours. Esthélis showed good or excellent results in most patients with atrophic scars, and these were perceived as even better when patients evaluated the cosmetic improvement. The best results were observed in patients with more deforming scars such as surgical scars or trauma.

  7. The effects of chronic consumption of heroin on basal and vagal electrical-stimulated gastric acid and pepsin secretion in rat.

    Science.gov (United States)

    Rafsanjani, Fatemeh N; Maghouli, Fatemeh; Vahedian, Jalal; Esmaeili, Farzaneh

    2004-10-01

    Addiction to opium and heroin is not only an important social and individual problem in the world but it also affects the human physiology and multiple systems. The aim of this study is to determine the effects of chronic heroin consumption on basal and vagus electrical-stimulated total gastric acid and pepsin secretion in rats. The study was carried out in the Department of Physiology, Kerman University of Medical Sciences, Iran from August 2002 to June 2003. Both male and female rats weighing 200-250 g were used. Rats received daily doses of heroin intraperitoneally starting from 0.2 mg/kg to 0.1 mg/kg/day up to the maintenance level of 0.7 mg/kg and continued until day 12. After anesthesia, tracheotomy and laparotomy, gastric effluents were collected by washout technique with a 15 minutes interval. The total titrable acid was measured by manual titrator, and the total pepsin content was measured by Anson's method. Vagal electrical stimulation was used to stimulate the secretion of acid and pepsin. Heroin results in a significant decrease in total basal acid and pepsin secretions (4.10 +/- 0.18 mmol/15 minutes versus 2.40 +/- 0.16 mmol/15 minutes for acid, pacid and pepsin secretions in vagotomized condition. Heroin also causes a significant decrease in vagal-electrically stimulated acid and pepsin secretions (14.70 +/- 0.54 mmol/15 minutes versus 4.30 +/- 0.21 mmol/15 minutes for acid, pacid and pepsin secretion, but not in vagotomized condition. Heroin may decrease acid secretion by inhibiting vagal release of acetylcholine within the gastric wall. Other probable mechanisms include: presynaptic inhibition of acetylcholine release or depressing the vagal center, inhibition of pentagastrin induced acid secretion, inhibitory effects via central mechanisms, probably mediated by the opiate receptors. Further studies are needed to recognize the actual mechanism.

  8. Conjugated Linoleic Acid Stimulates Apoptosis in RH and Tehran Strains of Toxoplasma gondii, in Vitro.

    Directory of Open Access Journals (Sweden)

    Jebreil Shamseddin

    2015-06-01

    Full Text Available The aim of this study was to evaluate the effects of conjugated linoleic acid (CLA on apoptosis of tachyzoites of T. gondii, RH strain (type I and the cyst-forming Tehran strain (type II in vitro.Toxoplasma strains were injected into the peritoneal cavity of BALB/c mice. The Tehran strain forms cysts in the brain of mice. Bradyzoites within the cysts are reactivated to proliferative tachyzoites, by dexamethasone. Tachyzoites were aspirated from the peritoneum of infected mice, and the percentage of viable parasites was estimated with trypan blue staining. Tachyzoites were inoculated into HeLa cells cultivated in DMEM medium. Different concentrations of CLA were evaluated on T. gondii in HeLa cells by the tetrazolium (MTT colorimetric assay. Differentiation between apoptosis and cell death was determined by flow cytometry using Annexin V and propidium iodide (PI double staining. The statistical analysis performed by GraphPad Prism version 6.00.CLA induces apoptosis in virulent (RH and avirulent (Tehran strains of T. gondii. The results of MTT indicated that CLA could decrease the proliferation of tachyzoites of both strains in HeLa cells.Conjugated linoleic acid has anti-toxoplasmacidal activity on tachyzoites of T. gondii. Therefore, we recommended further studies on this component in order to achieve a new drug against the parasite.

  9. A Study of the Differential Effects of Eicosapentaenoic Acid (EPA) and Docosahexaenoic Acid (DHA) on Gene Expression Profiles of Stimulated Thp-1 Macrophages.

    Science.gov (United States)

    Allam-Ndoul, Bénédicte; Guénard, Frédéric; Barbier, Olivier; Vohl, Marie-Claude

    2017-04-25

    Background: An appropriate intake of omega-3 ( n -3) fatty acids (FAs) such as eicosapentaenoic and docosahexaenoic acid (EPA/DHA) from marine sources is known to have anti-inflammatory effects. However, molecular mechanisms underlying their beneficial effects on health are not fully understood. The aim of the present study was to characterize gene expression profiles of THP-1 macrophages, incubated in either EPA or DHA and stimulated with lipopolysaccharide (LPS), a pro-inflammatory agent. Methods: THP-1 macrophages were incubated into 10, 50 and 75 µM of EPA or DHA for 24 h, and 100 nM of LPS was added to the culture media for 18 h. Total mRNA was extracted and gene expression examined by microarray analysis using Illumina Human HT-12 expression beadchips (Illumina). Results: Pathway analysis revealed that EPA and DHA regulate genes involved in cell cycle regulation, apoptosis, immune response and inflammation, oxidative stress and cancer pathways in a differential and dose-dependent manner. Conclusions: EPA and DHA appear to exert differential effects on gene expression in THP-1 macrophages. Specific effects of n -3 FAs on gene expression levels are also dose-dependent.

  10. Stimulation of human gingival fibroblasts viability and growth by roots treated with high intensity lasers, photodynamic therapy and citric acid.

    Science.gov (United States)

    Karam, Paula Stephania Brandão Hage; Ferreira, Rafael; Oliveira, Rodrigo Cardoso; Greghi, Sebastião Luiz Aguiar; de Rezende, Maria Lúcia Rubo; Sant'Ana, Adriana Campos Passanezi; Zangrando, Mariana Schutzer Ragghianti; Damante, Carla Andreotti

    2017-09-01

    The aim of this study was to compare the effect of root biomodification by lasers, citric acid and antimicrobial photodynamic therapy (aPDT) on viability and proliferation of human gingival fibroblasts (FGH). Groups were divided in control (CC - only cells), and root fragments treated by: scaling and root planing (positice control - SC), Er:YAG (ER-60mJ,10pps,10Hz,10s,2940nm), Nd:YAG (ND-0.5W,15Hz,10s,1640nm), antimicrobial photodynamic therapy (PDT-InGaAIP,30mW,45J/cm 2 ,30s,660nm,toluidine blue O), citric acid plus tetracycline (CA). Fibroblasts (6th passage, 2×10 3 ) were cultivated in a 24-h conditioned medium by the treated root fragments. Cell viability was measured by MTT test at 24, 48, 72 and 96h. In a second experiment, FGH cells (10 4 ) were cultivated on root fragments which received the same treatments. After 24, 48, 72h the number of cells was counted in SEM pictures. In addition, chemical elements were analyzed by energy dispersive spectroscopy (EDS). Data was analyzed by two-way ANOVA (first experiment), repeated measures ANOVA (second experiment) and ANOVA (EDS experiment) tests complemented by Tukey's test (pplaning stimulated fibroblast viability while Er:YAG and Nd:YAG treated root surfaces presented higher number of cells. Copyright © 2017. Published by Elsevier Ltd.

  11. Insulin binding and stimulation of hexose and amino acid transport by normal and receptor-defective human fibroblasts

    International Nuclear Information System (INIS)

    Longo, N.; Nagata, N.; Danner, D.; Priest, J.; Elsas, L.

    1986-01-01

    The authors analyzed insulin receptors in cells cultured from a sibship of related parents who had two offspring with severe insulin resistance (Leprechaunism). 124 I-Insulin (1 ng/ml) binding to skin fibroblasts from the proband, mother, and father was 9, 60 and 62% of control cells, respectively, at equilibrium, Non-linear regression analysis, utilizing a two receptors model, of curvilinear Scatchard plots indicated a reduced number of high-affinity binding sites in both parents. Influx of L-Proline (System A), L-Serine (ASC) and L-Leucine (L) was similar in control and mutant cells. Similarly, during the depletion of intracellular amino acid pools, there was a release from transinhibition for System A and a decrease of transstimulation of Systems ASC and L in both cell lines. Surprisingly, insulin augmented, normally, A system influx with an ED 50 = 70 ng/ml at 24 0 C and 7 ng/ml at 37 0 C. By contrast insulin failed to simulated 3-0-methyl-D-glucose influx into the proband's cells, while normal cells were stimulated 30% with an ED 50 of 6 ng/ml. These results indicate that defective high-affinity insulin binding is inherited as an autosomal recessive trait; that general membrane functions are intact; that insulin regulates A system amino acid and hexose transport by two different mechanisms; and, that the latter mechanism is impaired by this family's receptor mutation

  12. To Stimulate or Inhibit? That Is the Question for the Function of Abscisic Acid.

    Science.gov (United States)

    Humplík, Jan F; Bergougnoux, Véronique; Van Volkenburgh, Elizabeth

    2017-10-01

    Physiologically, abscisic acid (ABA) is believed to be a general inhibitor of plant growth, including during the crucial early development of seedlings. However, this view contradicts many reports of stimulatory effects of ABA that, so far, have not been considered in the debate concerning ABA's function in plant development. To address this apparent contradiction, we propose a hypothetical mechanism to explain how ABA might contribute to the promotion of cell expansion. We wish to overturn conventional views on ABA's role during juvenile plant development and put forward the idea that, as for other phytohormones, the role of ABA is determined by dose and sensitivity and ranges from stimulatory to inhibitory effects. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Tif-stimulated deoxyribonucleic acid repair in Escherichia coli K-12

    International Nuclear Information System (INIS)

    Castellazzi, M.; Jacques, M.; George, J.

    1980-01-01

    Bacterial survival is significantly increased after ultraviolet irradiation in tif sfi cells, provided that the thermosensitive tif mutation has been expressed at 41 0 C before irradiation. This tif-mediated reactivation of ultraviolet irradiated bacteria needs de novo protein synthesis, as is the case for the tif-mediated reactivation of ultraviolet-irradiated phage lambda. However, in striking contrast to the phage reactivation process, this tif-mediated reactivation is no longer associated with mutagenesis. It also requires the presence of the uvrA + excision function. These results strongly suggest the existence in Escherichia coli K-12 of a repair pathway acting on bacterial deoxyribonucleic acid which is inducible, error free, and uvr dependent

  14. Ascorbic acid deficiency stimulates hepatic expression of inflammatory chemokine, cytokine-induced neutrophil chemoattractant-1, in scurvy-prone ODS rats.

    Science.gov (United States)

    Horio, Fumihiko; Kiyama, Keiichiro; Kobayashi, Misato; Kawai, Kaori; Tsuda, Takanori

    2006-02-01

    ODS rat has a hereditary defect in ascorbic acid biosynthesis and is a useful animal model for elucidating the physiological role of ascorbic acid. We previously demonstrated by using ODS rats that ascorbic acid deficiency changes the hepatic gene expression of acute phase proteins, as seen in acute inflammation. In this study, we investigated the effects of ascorbic acid deficiency on the production of inflammatory chemokine, cytokine-induced neutrophil chemoattractant-1 (CINC-1), in ODS rats. Male ODS rats (6 wk of age) were fed a basal diet containing ascorbic acid (300 mg/kg diet) or a diet without ascorbic acid for 14 d. Obvious symptoms of scurvy were not observed in the ascorbic acid-deficient rats. Ascorbic acid deficiency significantly elevated the serum concentration of CINC-1 on d 14. The liver and spleen CINC-1 concentrations in the ascorbic acid-deficient rats were significantly elevated to 600% and 180% of the respective values in the control rats. However, the lung concentration of CINC-1 was not affected by ascorbic acid deficiency. Ascorbic acid deficiency significantly elevated the hepatic mRNA level of CINC-1 (to 480% of the value in the control rats), but not the lung mRNA level. These results demonstrate that ascorbic acid deficiency elevates the serum, liver and spleen concentrations of CINC-1 as seen in acute inflammation, and suggest that ascorbic acid deficiency stimulate the hepatic CINC-1 gene expression.

  15. Excitatory amino acid receptor blockade within the caudal pressor area and rostral ventrolateral medulla alters cardiovascular responses to nucleus raphe obscurus stimulation in rats

    Directory of Open Access Journals (Sweden)

    Silva N.F.

    2002-01-01

    Full Text Available Pressor responses elicited by stimulation of the nucleus raphe obscurus (NRO depend on the integrity of the rostral ventrolateral medulla (RVLM. Therefore, to test the participation of excitatory amino acid (EAA receptors in the cardiovascular responses evoked by NRO stimulation (1 ms, 100 Hz, 40-70 µA, for 10 s, the EAA antagonist kynurenic acid (Kyn was microinjected at different sites in the ventrolateral medullar surface (2.7 nmol/200 nl of male Wistar rats (270-320 g, N = 39 and NRO stimulation was repeated. The effects of NRO stimulation were: hypertension (deltaMAP = +43 ± 1 mmHg, P<0.01, bradycardia (deltaHR = -30 ± 7 bpm, P<0.01 and apnea. Bilateral microinjection of Kyn into the RVLM, which did not change baseline parameters, almost abolished the bradycardia induced by NRO stimulation (deltaHR = -61 ± 3 before vs -2 ± 3 bpm after Kyn, P<0.01, N = 7. Unilateral microinjection of Kyn into the CVLM did not change baseline parameters or reduce the pressor response to NRO stimulation (deltaMAP = +46 ± 5 before vs +48 ± 5 mmHg after Kyn, N = 6. Kyn bilaterally microinjected into the caudal pressor area reduced blood pressure and heart rate and almost abolished the pressor response to NRO stimulation (deltaMAP = +46 ± 4 mmHg before vs +4 ± 2 mmHg after Kyn, P<0.01, N = 7. These results indicate that EAA receptors on the medullary ventrolateral surface play a role in the modulation of the cardiovascular responses induced by NRO stimulation, and also suggest that the RVLM participates in the modulation of heart rate responses and that the caudal pressor area modulates the pressor response following NRO stimulation.

  16. Ascorbic acid treatment elevates follicle stimulating hormone and testosterone plasma levels and enhances sperm quality in albino Wistar rats.

    Science.gov (United States)

    Okon, Uduak Akpan; Utuk, Ikponoabasi Ibanga

    2016-01-01

    Infertility issues have been linked to the effect of oxidative reaction in the reproductive system. This study evaluated the effect of ascorbic acid, on fertility parameters of male albino Wistar rats was studied. Eighteen albino Wistar rats weighed between 178 g and 241 g were used, randomly assigned into three groups. Group 1 was the control group; oral gavaged 5 ml of distilled water; Groups 2 and 3 were administered medium dose (250 mg/kg) and high dose of ascorbic acid (400 mg/kg), respectively; twice daily for 21 days. Blood samples were obtained by cardiac puncture, and blood serum was obtained for hormonal assay, and the testes were harvested for sperm analysis. Follicle stimulating hormone levels significantly increased in the high-dose group as compared to both the control and medium dose groups. Luteinizing hormone levels in the medium dose group decreased significantly as compared to the control group. Testosterone significantly increased in both the medium- and high-dose groups as compared to the control group. Sperm motility increased significantly in the high-dose group as compared to both control and medium-dose groups. Percentage sperm concentration decreased significantly in the medium-dose group when compared to the control and increased significantly in the high-dose group as compared to the medium-dose group. For percentage normal morphology, there was a dose-dependent increase in the test groups when compared to control group. These results are indicative of a positive influence of ascorbic acid on male fertility modulators and may therefore, serve as a potential adjuvant treatment for male infertility cases.

  17. Bioaccessibility of tocopherols, carotenoids, and ascorbic acid from milk- and soy-based fruit beverages: influence of food matrix and processing.

    Science.gov (United States)

    Cilla, Antonio; Alegría, Amparo; de Ancos, Begoña; Sánchez-Moreno, Concepción; Cano, M Pilar; Plaza, Lucía; Clemente, Gonzalo; Lagarda, María J; Barberá, Reyes

    2012-07-25

    A study was made of the effect of high-pressure processing (HPP) and thermal treatment (TT) on plant bioactive compounds (tocopherols, carotenoids, and ascorbic acid) in 12 fruit juice-milk beverages and of how the food matrix [whole milk (JW), skimmed milk (JS), and soy milk (JSy)] modulates their bioaccessibility (%). HPP (400 MPa/40 °C/5 min) produced a significant decrease in carotenoid and ascorbic acid bioaccessibility in all three beverages and maintained the bioaccessibility of tocopherols in JW and JS while decreasing it in JSy. TT (90 °C/30 s) produced a significant decrease in tocopherol and carotenoid bioaccessibility in all three beverages and increased the bioaccessibility of ascorbic acid. With regard to the food matrix, α-tocopherol and ascorbic acid bioaccessibility was greatest in JW beverages and lowest in JSy beverages, whereas no significant differences were found among the three beverages in terms of carotenoid bioaccessibility. HPP-treated samples showed higher tocopherol and carotenoid bioaccessibility than TT-treated samples, thus indicating that HPP combined with a milk matrix positively modulates the bioaccessibility of certain types of bioactive components of food, mainly those of a lipophilic nature.

  18. [Effect of citric acid stimulation on salivary alpha-amylase, total protein, salivary flow rate and pH value in Pi deficiency children].

    Science.gov (United States)

    Yang, Ze-min; Chen, Long-hui; Lin, Jing; Zhang, Min; Yang, Xiao-rong; Chen, Wei-wen

    2015-02-01

    To compare the effect of citric acid stimulation on salivary alpha-amylase (sAA), total protein (TP), salivary flow rate, and pH value between Pi deficiency (PD) children and healthy children, thereby providing evidence for Pi controlling saliva theory. Twenty PD children were recruited, and 29 healthy children were also recruited at the same time. Saliva samples from all subjects were collected before and after citric acid stimulation. The sAA activity and amount, TP contents, salivary flow rate, and pH value were determined and compared. (1) Citric acid stimulation was able to significantly increase salivary flow rate, pH value, sAA activities, sAA specific activity and sAA amount (including glycosylated and non-glycosylated sAA amount) in healthy children (Psalivary flow rate, pH value, and glycosylated sAA levels in PD children (Psalivary indices between the two groups (P>0.05), salivary indices except salivary flow rate and glycosylated sAA levels decreased more in PD children. There was statistical difference in sAA activity ratio, sAA specific activity ratio, and the ratio of glycosylated sAA levels between PD children and healthy children (P<0.05). PD children had decreased response to citric acid stimulation.

  19. Hyaluronic Acid Suppresses the Expression of Metalloproteinases in Osteoarthritic Cartilage Stimulated Simultaneously by Interleukin 1β and Mechanical Load.

    Directory of Open Access Journals (Sweden)

    Florian Pohlig

    Full Text Available In patients with osteoarthritis (OA, intraarticular injection of hyaluronic acid (HA frequently results in reduced pain and improved function for prolonged periods of time, i.e. more than 6 months. However, the mechanisms underlying these effects are not fully understood. Our underlying hypothesis is that HA modifies the enzymatic breakdown of joint tissues.To test this hypothesis, we examined osteochondral cylinders from 12 OA patients. In a bioreactor, these samples were stimulated by interleukin 1β (Il1ß (2 ng/ml plus mechanical load (2.0 Mpa at 0.5 Hz horizontal and 0.1 Hz vertical rotation, thus the experimental setup recapitulated both catabolic and anabolic clues of the OA joint.Upon addition of HA at either 1 or 3 mg/ml, we observed a significant suppression of expression of metalloproteinase (MMP-13. A more detailed analysis based on the Kellgren and Lawrence (K&L OA grade, showed a much greater degree of suppression of MMP-13 expression in grade IV as compared to grade II OA. In contrast to the observed MMP-13 suppression, treatment with HA resulted in a suppression of MMP-1 expression only at 1 mg/ml HA, while MMP-2 expression was not significantly affected by either HA concentration.Together, these data suggest that under concurrent catabolic and anabolic stimulation, HA exhibits a pronounced suppressive effect on MMP-13. In the long-run these findings may benefit the development of treatment strategies aimed at blocking tissue degradation in OA patients.

  20. Gamma-aminobutyric acid (GABA) stimulates pancreatic cancer growth through overexpressing GABAA receptor pi subunit.

    Science.gov (United States)

    Takehara, Akio; Hosokawa, Masayo; Eguchi, Hidetoshi; Ohigashi, Hiroaki; Ishikawa, Osamu; Nakamura, Yusuke; Nakagawa, Hidewaki

    2007-10-15

    Gamma-aminobutyric acid (GABA) functions primarily as an inhibitory neurotransmitter in the mature central nervous system, and GABA/GABA receptors are also present in nonneural tissues, including cancer, but their precise function in nonneuronal or cancerous cells has thus far been poorly defined. Through the genome-wide cDNA microarray analysis of pancreatic ductal adenocarcinoma (PDAC) cells as well as subsequent reverse transcription-PCR and Northern blot analyses, we identified the overexpression of GABA receptor pi subunit (GABRP) in PDAC cells. We also found the expression of this peripheral type GABAA receptor subunit in few adult human organs. Knockdown of endogenous GABRP expression in PDAC cells by small interfering RNA attenuated PDAC cell growth, suggesting its essential role in PDAC cell viability. Notably, the addition of GABA into the cell culture medium promoted the proliferation of GABRP-expressing PDAC cells, but not GABRP-negative cells, and GABAA receptor antagonists inhibited this growth-promoting effect by GABA. The HEK293 cells constitutively expressing exogenous GABRP revealed the growth-promoting effect of GABA treatment. Furthermore, GABA treatment in GABRP-positive cells increased intracellular Ca2+ levels and activated the mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/Erk) cascade. Clinical PDAC tissues contained a higher level of GABA than normal pancreas tissues due to the up-regulation of glutamate decarboxylase 1 expression, suggesting their autocrine/paracrine growth-promoting effect in PDACs. These findings imply that GABA and GABRP could play important roles in PDAC development and progression, and that this pathway can be a promising molecular target for the development of new therapeutic strategies for PDAC.

  1. Retrovirus-specific differences in matrix and nucleocapsid protein-nucleic acid interactions: implications for genomic RNA packaging.

    Science.gov (United States)

    Sun, Meng; Grigsby, Iwen F; Gorelick, Robert J; Mansky, Louis M; Musier-Forsyth, Karin

    2014-01-01

    Retroviral RNA encapsidation involves a recognition event between genomic RNA (gRNA) and one or more domains in Gag. In HIV-1, the nucleocapsid (NC) domain is involved in gRNA packaging and displays robust nucleic acid (NA) binding and chaperone functions. In comparison, NC of human T-cell leukemia virus type 1 (HTLV-1), a deltaretrovirus, displays weaker NA binding and chaperone activity. Mutation of conserved charged residues in the deltaretrovirus bovine leukemia virus (BLV) matrix (MA) and NC domains affects virus replication and gRNA packaging efficiency. Based on these observations, we hypothesized that the MA domain may generally contribute to NA binding and genome encapsidation in deltaretroviruses. Here, we examined the interaction between HTLV-2 and HIV-1 MA proteins and various NAs in vitro. HTLV-2 MA displays higher NA binding affinity and better chaperone activity than HIV-1 MA. HTLV-2 MA also binds NAs with higher affinity than HTLV-2 NC and displays more robust chaperone function. Mutation of two basic residues in HTLV-2 MA α-helix II, previously implicated in BLV gRNA packaging, reduces NA binding affinity. HTLV-2 MA binds with high affinity and specificity to RNA derived from the putative packaging signal of HTLV-2 relative to nonspecific NA. Furthermore, an HIV-1 MA triple mutant designed to mimic the basic character of HTLV-2 MA α-helix II dramatically improves binding affinity and chaperone activity of HIV-1 MA in vitro and restores RNA packaging to a ΔNC HIV-1 variant in cell-based assays. Taken together, these results are consistent with a role for deltaretrovirus MA proteins in viral RNA packaging.

  2. Stiffness of hyaluronic acid gels containing liver extracellular matrix supports human hepatocyte function and alters cell morphology.

    Science.gov (United States)

    Deegan, Daniel B; Zimmerman, Cynthia; Skardal, Aleksander; Atala, Anthony; Shupe, Thomas D

    2015-03-01

    Tissue engineering and cell based liver therapies have utilized primary hepatocytes with limited success due to the failure of hepatocytes to maintain their phenotype in vitro. In order to overcome this challenge, hyaluronic acid (HA) cell culture substrates were formulated to closely mimic the composition and stiffness of the normal liver cellular microenvironment. The stiffness of the substrate was modulated by adjusting HA hydrogel crosslinking. Additionally, the repertoire of bioactive molecules within the HA substrate was bolstered by supplementation with normal liver extracellular matrix (ECM). Primary human hepatocyte viability and phenotype were determined over a narrow physiologically relevant range of substrate stiffnesses from 600 to 4600Pa in both the presence and absence of liver ECM. Cell attachment, viability, and organization of the actin cytoskeleton improved with increased stiffness up to 4600Pa. These differences were not evident in earlier time points or substrates containing only HA. However, gene expression for the hepatocyte markers hepatocyte nuclear factor 4 alpha (HNF4α) and albumin significantly decreased on the 4600Pa stiffness at day 7 indicating that cells may not have maintained their phenotype long-term at this stiffness. Function, as measured by albumin secretion, varied with both stiffness and time in culture and peaked at day 7 at the 1200Pa stiffness, slightly below the stiffness of normal liver ECM at 3000Pa. Overall, gel stiffness affected primary human hepatocyte cell adhesion, functional marker expression, and morphological characteristics dependent on both the presence of liver ECM in gel substrates and time in culture. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Influences of AMY1 gene copy number and protein expression on salivary alpha-amylase activity before and after citric acid stimulation in splenic asthenia children.

    Science.gov (United States)

    Yang, Zemin; Lin, Jing; Chen, Longhui; Zhang, Min; Yang, Xiaorong; Chen, Weiwen

    2015-06-01

    To compare the correlations between salivary alpha-amylase (sAA) activity and amylase, alpha 1 (salivary) gene (AMYl) copy number or its gene expression between splenic asthenia and healthy children, and investigate the reasons of attenuated sAA activity ratio before and after citric acid stimulation in splenic asthenia children. Saliva samples from 20 splenic asthenia children and 29 healthy children were collected before and after citric acid stimulation. AMYl copy number, sAA activity, and total sAA and glycosylated sAA contents were determined, and their correlations were analyzed. Although splenic asthenia and healthy children had no differences in AMY1 copy number, splenic asthenia children had positive correlations between AMY1 copy number and sAA activity before or after citric acid stimulation. Splenic asthenia children had a higher sAA glycosylated proportion ratio and glycosylated sAA content ratio, while their total sAA content ratio and sAA activity ratio were lower compared with healthy children. The glycosylated sAA content ratio was higher than the total sAA content ratio in both groups. Splenic asthenia and healthy children had positive correlations between total sAA or glycosylated sAA content and sAA activity. However, the role played by glycosylated sAA content in sAA activity in healthy children increased after citric acid stimulation, while it decreased in splenic asthenia children. Genetic factors like AMY1 copy number variations, and more importantly, sAA glycosylation abnormalities leading to attenuated sAA activity after citric acid stimulation, which were the main reasons of the attenuated sAA activity ratio in splenic asthenia children compared with healthy children.

  4. Fatty acid 16:4(n-3) stimulates a GPR120-induced signaling cascade in splenic macrophages to promote chemotherapy resistance

    DEFF Research Database (Denmark)

    Houthuijzen, Julia M; Oosterom, Ilse; Hudson, Brian D

    2017-01-01

    Although chemotherapy is designed to eradicate tumor cells, it also has significant effects on normal tissues. The platinum-induced fatty acid 16:4(n-3) (hexadeca-4,7,10,13-tetraenoic acid) induces systemic resistance to a broad range of DNA-damaging chemotherapeutics. We show that 16:4(n-3) exerts....... M., Peeper, D. S., Jafari Sadatmand, S., Roodhart, J. M. L., van de Lest, C. H. A., Ulven, T., Ishihara, K., Milligan, G., Voest, E. E. Fatty acid 16:4(n-3) stimulates a GPR120-induced signaling cascade in splenic macrophages to promote chemotherapy resistance....

  5. Influence of vaginal bacteria and D- and L-lactic acid isomers on vaginal extracellular matrix metalloproteinase inducer: implications for protection against upper genital tract infections.

    Science.gov (United States)

    Witkin, Steven S; Mendes-Soares, Helena; Linhares, Iara M; Jayaram, Aswathi; Ledger, William J; Forney, Larry J

    2013-08-06

    We evaluated levels of vaginal extracellular matrix metalloproteinase inducer (EMMPRIN) and matrix metalloproteinase (MMP-8) in vaginal secretions in relation to the composition of vaginal bacterial communities and D- and L-lactic acid levels. The composition of vaginal bacterial communities in 46 women was determined by pyrosequencing the V1 to V3 region of 16S rRNA genes. Lactobacilli were dominant in 71.3% of the women, followed by Gardnerella (17.4%), Streptococcus (8.7%), and Enterococcus (2.2%). Of the lactobacillus-dominated communities, 51.5% were dominated by Lactobacillus crispatus, 36.4% by Lactobacillus iners, and 6.1% each by Lactobacillus gasseri and Lactobacillus jensenii. Concentrations of L-lactic acid were slightly higher in lactobacillus-dominated vaginal samples, but most differences were not statistically significant. D-Lactic acid levels were higher in samples containing L. crispatus than in those with L. iners (Pvaginal communities dominated by species of lactobacilli was in concordance with the proportions found in axenic cultures of the various species grown in vitro. Levels of L-lactic acid (Pvaginal concentrations of EMMPRIN and MMP-8 levels were highly correlated (Pinfections. A large proportion of preterm births (>50%) result from infections caused by bacteria originating in the vagina, which requires that they traverse the cervix. Factors that influence susceptibility to these infections are not well understood; however, there is evidence that matrix metalloproteinase (MMP-8) is known to alter the integrity of the cervix. In this work, we show that concentrations of vaginal extracellular matrix metalloproteinase inducer (EMMPRIN) are influenced by members of the vaginal microbial community and concentrations of D- or L-lactic acid isomers in vaginal secretions. Elevated levels of D-lactic acid and the ratio of D- to L-lactic acid influence EMMPRIN concentrations as well as MMP-8 levels. Thus, isomers of lactic acid may function as

  6. Reduction of Inflammatory Responses and Enhancement of Extracellular Matrix Formation by Vanillin-Incorporated Poly(Lactic-co-Glycolic Acid) Scaffolds

    OpenAIRE

    Lee, Yujung; Kwon, Jeongil; Khang, Gilson; Lee, Dongwon

    2012-01-01

    Vanillin is one of the major components of vanilla, a commonly used flavoring agent and preservative and is known to exert potent antioxidant and anti-inflammatory activities. In this work, vanillin-incorporated poly(lactic-co-glycolic acid) (PLGA) films and scaffolds were fabricated to evaluate the effects of vanillin on the inflammatory responses and extracellular matrix (ECM) formation in vitro and in vivo. The incorporation of vanillin to PLGA films induced hydrophilic nature, resulting i...

  7. Wound healing effects of collagen-laminin dermal matrix impregnated with resveratrol loaded hyaluronic acid-DPPC microparticles in diabetic rats.

    Science.gov (United States)

    Gokce, Evren H; Tuncay Tanrıverdi, Sakine; Eroglu, Ipek; Tsapis, Nicolas; Gokce, Goksel; Tekmen, Isıl; Fattal, Elias; Ozer, Ozgen

    2017-10-01

    An alternative formulation for the treatment of diabetic foot wounds that heal slowly is a requirement in pharmaceutical field. The aim of this study was to develop a dermal matrix consisting of skin proteins and lipids with an antioxidant that will enhance healing and balance the oxidative stress in the diabetic wound area due to the high levels of glucose. Thus a novel three dimensional collagen-laminin porous dermal matrix was developed by lyophilization. Resveratrol-loaded hyaluronic acid and dipalmitoylphosphatidylcholine microparticles were combined with this dermal matrix. Characterization, in vitro release, microbiological and in vivo studies were performed. Spherical microparticles were obtained with a high RSV encapsulation efficacy. The microparticles were well dispersed in the dermal matrix from the surface to deeper layers. Collagenase degraded dermal matrix, however the addition of RSV loaded microparticles delayed the degradation time. The release of RSV was sustained and reached 70% after 6h. Histological changes and antioxidant parameters in different treatment groups were investigated in full-thickness excision diabetic rat model. Collagen fibers were intense and improved by the presence of formulation without any signs of inflammation. The highest healing score was obtained with the dermal matrix impregnated with RSV-microparticles with an increased antioxidant activity. Collagen-laminin dermal matrix with RSV microparticles was synergistically effective due to presence of skin components in the formulation and controlled release achieved. This combination is a safe and promising option for the treatment of diabetic wounds requiring long recovery. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Immunoregulation of antitumor response; differential secretion of arachidonic acid metabolites by macrophages during stimulation ''in vitro'' with BCG and ''Corynebacterium parvum''

    International Nuclear Information System (INIS)

    Tomecki, Jaroslaw; Sukiennik, Jadwiga; Kordowiak, Anna

    1993-01-01

    The level of arachidonic acid (AA) metabolites in the supernatants of cultures peritoneal exudate cells (PEC) were studied under various conditions using BCG and ''Corynebacterium parvum'' as stimulators. The metabolite levels were analyzed by thin layer chromatography (TLC). The degree of macrophage cytotoxic/cytostatic activity was dependent on the dose and character of stimulators used and the source of macrophages. The application of micro cytotoxicity assay for the evaluation of tumor cell lysis (lung sarcoma SaL-1) ''in vitro'' revealed that peritoneal macrophages from healthy and tumor bearing BALB/c mice may affect the degree of antitumor response. In the supernatants of cultured PEC from tumor bearing mice AA level increased (by 10-fold) in comparison with PEC from healthy mice. Stimulation with BCG induced over a double level of AA in PEC isolated from tumor bearing mice non-stimulated or stimulated with ''C.parvum''. A lower level of prostaglandins (PGs) was found in the supernatants of cultured PEC isolated from healthy mice (stimulated and non-stimulated), but the highest level of PGs was observed in the supernatants of cultured PEC isolated from tumor bearing mice stimulated with BCG. The unique metabolite of AA was found only in the supernatants form non-stimulated PEC from tumor bearing mice. PEC from tumor bearing mice produced metabolites of AA which were not detected in control group. These results suggest that macrophages also play a regulatory role by secretion of AA. This process can be modified by bacterial antigens. (author). 21 refs, 7 figs

  9. Cohesive Polydensified Matrix® hyaluronic acid volumizer injected for cheek augmentation has additional positive effect on nasolabial folds

    Directory of Open Access Journals (Sweden)

    Gauglitz G

    2017-12-01

    Full Text Available Gerd Gauglitz,1 Stephanie Steckmeier,1 Julian Pötschke,2 Hannah Schwaiger,1 1Department of Dermatology and Allergy, Ludwig-Maximilian University, Munich, Germany; 2Department of Plastic and Hand Surgery, Klinikum St Georg gGmbH, Leipzig, Germany Purpose: Cohesive Polydensified Matrix® hyaluronic acid (CPM-HA volumizer has been used successfully for several years to reverse biometric volume loss during facial aging. This observational study explored the additive effect on nasolabial folds when CPM-HA volumizer is injected into the neighboring cheek area.Patients and methods: In this open-label, prospective, postmarketing noninterventional study, 18 adult patients seeking esthetic enhancement of the lateral cheek hollows and cheekbone area were injected with CPM-HA volumizer integrated with lidocaine (CPM-HA-VL in the upper or lower cheek area. Safety and performance of CPM-HA-VL up to 12 months after injection with follow-up visits at week 4 and month 3, 6, and 12 were assessed. The primary endpoint was improvement of cheek fullness on the validated Merz Aesthetics Scales. Additionally, changes in nasolabial folds were quantified using a phaseshift rapid in vivo measurement of skin optical three-dimensional (3D in vivo measurement device. Results: Patients (94.4% female, median age 52 years, age range 39–69 years were injected with a mean volume of 2.5±1.1 mL CPM-HA-VL per side. Immediately after injection, mean severity for upper and lower cheek fullness assessed on the validated MAS improved from 2.5±0.6 and 2.8±0.5, respectively, to 1.0±0.0, and remained unchanged through month 12. Improvement in relation to baseline was attested on the Global Aesthetics Improvement Scale for all assessments. Compared with baseline, the following assessments offered a statistical significance in the reduction of wrinkle depth of nasolabial folds (maximum depth reduction by 30.4% at 3 months according to optical 3D in vivo measurements. Pain during

  10. Modeling and optimizing the design of matrix treatments in carbonate reservoirs with self-diverting acid systems

    International Nuclear Information System (INIS)

    Bulgakova, G T; Kharisov, R Ya; Sharifullin, A R; Pestrikov, A V

    2015-01-01

    Application of a self-diverting-acid based on viscoelastic surfactant (SDVA) is a promising technology for improving the efficacy of acid treatment in oil and gas-bearing carbonate reservoirs. In this study, we present a mathematical model for assessing SDVA flow and reaction with carbonate rock using the SDVA rheological characteristics. The model calculates the technological parameters for acidizing operations and the prediction of well productivity after acid treatment, in addition to technical and economic optimization of the acidizing process by modeling different acid treatment options with varying volumes, injection rates, process fluids stages and initial economic scenarios

  11. Chitin stimulates expression of acidic mammalian chitinase and eotaxin-3 by human sinonasal epithelial cells in vitro.

    Science.gov (United States)

    Lalaker, Ashley; Nkrumah, Louis; Lee, Won-Kyung; Ramanathan, Murugappan; Lane, Andrew P

    2009-01-01

    Sinonasal epithelial cells participate in host defense by initiating innate immune mechanisms against potential pathogens. Antimicrobial innate mechanisms have been shown to involve Th1-like inflammatory responses. Although epithelial cells can also be induced by Th2 cytokines to express proeosinophilic mediators, no environmental agents have been identified that promote this effect. Human sinonasal epithelial cells from patients with chronic rhinosinusitis with nasal polyps (CRSwNPs) and controls were harvested and grown in primary culture. Cell cultures were exposed to a range of concentrations of chitin for 24 hours, and mRNA for acidic mammalian chitinase (AMCase), eotaxin-3, and thymic stromal-derived lymphopoietin (TSLP) were assessed. Other cultures were exposed to interleukin 4 (IL- 4) alone and in combination with dust-mite antigen (DMA) for 36 hours. Extracted mRNA and cell culture supernatant were analyzed for expression of AMCase and eotaxin-3. Chitin induced a dose-dependent expression of AMCase and eotaxin-3 mRNA but not TSLP. Patients with recalcitrant CRSwNPs showed lower baseline expression of AMCase when compared with treatment-responsive CRSwNP and less induction of AMCase expression by chitin. DMA did not directly induce expression of AMCase or eotaxin-3. Expression of eotaxin-3 was stimulated by IL-4 and further enhanced with the addition of DMA. Levels of AMCase were not significantly affected by either IL-4 or DMA exposure. In some cases, the combination of IL-4 and DMA was able to induce AMCase expression in cell cultures not producing AMCase at baseline. The abundant biopolymer chitin appears to be recognized by a yet uncharacterized receptor on sinonasal epithelial cells. Chitin stimulates production of AMCase and eotaxin-3, two pro-Th2 effector proteins. This finding suggests the existence of a novel innate immune pathway for local defense against chitin-containing organisms in the sinonasal tract. Dysregulation of this function could

  12. Characterizing the release of different composition of dissolved organic matter in soil under acid rain leaching using three-dimensional excitation-emission matrix spectroscopy.

    Science.gov (United States)

    Liu, Li; Song, Cunyi; Yan, Zengguang; Li, Fasheng

    2009-09-01

    Although excitation-emission matrix spectroscopy (EEMS) has been widely used to characterize dissolved organic matter (DOM), there has no report that EEMS has been used to study the effects of acid rain on DOM and its composition in soil. In this work, we employed three-dimensional EEMS to characterize the compositions of DOM leached by simulated acid rain from red soil. The red soil was subjected to leaching of simulated acid rain of different acidity, and the leached DOM presented five main peaks in its EEMS: peak-A, related to humic acid-like (HA-like) material, at Ex/Em of 310-330/395-420nm; peak-B, related to UV fulvic acid-like (FA-like) material, at Ex/Em of 230-280/400-435nm; peak-C and peak-D, both related to microbial byproduct-like material, at Ex/Em of 250-280/335-355nm and 260-280/290-320nm, respectively; and peak-E, related to simple aromatic proteins, at Ex/Em of 210-240/290-340nm. EEMS analysis results indicated that most DOM could be lost from red soil in the early phase of acid rain leaching. In addition to the effects of the pH of acid rain, the loss of DOM also depended on the properties of its compositions and the solubility of their complexes with aluminum. HA-like and microbial byproduct-like materials could be more easily released from red soil by acid rain at both higher pH (4.5 and 5.6) and lower pH (2.5 and 3) than that at middle pH (3.5). On the contrary, FA-like material lost in a similar manner under the action of different acid rains with pH ranging from 2.5 to 5.6.

  13. Evaluating the efficacy of a structure-derived amino acid substitution matrix in detecting protein homologs by BLAST and PSI-BLAST

    Directory of Open Access Journals (Sweden)

    Nalin CW Goonesekere

    2009-06-01

    Full Text Available Nalin CW GoonesekereDepartment of Chemistry and Biochemistry, University of Northern iowa, Cedar Falls, IA, USAAbstract: The large numbers of protein sequences generated by whole genome sequencing projects require rapid and accurate methods of annotation. The detection of homology through computational sequence analysis is a powerful tool in determining the complex evolutionary and functional relationships that exist between proteins. Homology search algorithms employ amino acid substitution matrices to detect similarity between proteins sequences. The substitution matrices in common use today are constructed using sequences aligned without reference to protein structure. Here we present amino acid substitution matrices constructed from the alignment of a large number of protein domain structures from the structural classification of proteins (SCOP database. We show that when incorporated into the homology search algorithms BLAST and PSI-blaST, the structure-based substitution matrices enhance the efficacy of detecting remote homologs. Keywords: computational biology, protein homology, amino acid substitution matrix, protein structure

  14. Lipoxin A4 and lipoxin B4 stimulate the release but not the oxygenation of arachidonic acid in human neutrophils: Dissociation between lipid remodeling and adhesion

    Energy Technology Data Exchange (ETDEWEB)

    Nigam, S.; Fiore, S.; Luscinskas, F.W.; Serhan, C.N. (Brigham and Women' s Hospital, Boston, MA (USA))

    1990-06-01

    The profiles of actions of lipoxin A4 (LXA4) and lipoxin B4 (LXB4), two lipoxygenase-derived eicosanoids, were examined with human neutrophils. At nanomolar concentrations, LXA4 and LXB4 each stimulated the release of (1-14C)arachidonic acid from esterified sources in neutrophils. Lipoxin-induced release of (1-14C)arachidonic acid was both dose- and time-dependent and was comparable to that induced by the chemotactic peptide f-met-leu-phe. Time-course studies revealed that lipoxin A4 and lipoxin B4 each induced a biphasic release of (1-14C)arachidonic acid, which was evident within seconds (5-15 sec) in its initial phase and minutes (greater than 30 sec) in the second phase. In contrast, the all-trans isomers of LXA4 and LXB4 did not provoke (1-14C)AA release. Lipoxin-induced release of arachidonic acid was inhibited by prior treatment of the cells with pertussis toxin but not by its beta-oligomers, suggesting the involvement of guaninine nucleotide-binding regulatory proteins in this event. Dual radiolabeling of neutrophil phospholipid classes with (1-14C)arachidonic acid and (3H)palmitic acid showed that phosphatidylcholine was a major source of lipoxin-induced release of (1-14C)arachidonic acid. They also demonstrated that lipoxins rapidly stimulate both formation of phosphatidic acid as well as phospholipid remodeling. Although both LXA4 and LXB4 (10(-8)-10(-6) M) stimulated the release of (1-14C)arachidonic acid, neither compound evoked its oxygenation by either the 5- or 15-lipoxygenase pathways (including the formation of LTB4, 20-COOH-LTB4, 5-HETE, or 15-HETE). LXA4 and LXB4 (10(-7) M) each stimulated the elevation of cytosolic Ca2+ as monitored with Fura 2-loaded cells, albeit to a lesser extent than equimolar concentrations of FMLP. Neither lipoxin altered the binding of (3H)LTB4 to its receptor on neutrophils.

  15. Spatial structure peculiarities of influenza A virus matrix M1 protein in an acidic solution that simulates the internal lysosomal medium.

    Science.gov (United States)

    Shishkov, Alexander; Bogacheva, Elena; Fedorova, Natalia; Ksenofontov, Alexander; Badun, Gennadii; Radyukhin, Victor; Lukashina, Elena; Serebryakova, Marina; Dolgov, Alexey; Chulichkov, Alexey; Dobrov, Evgeny; Baratova, Lyudmila

    2011-12-01

    The structure of the C-terminal domain of the influenza virus A matrix M1 protein, for which X-ray diffraction data were still missing, was studied in acidic solution. Matrix M1 protein was bombarded with thermally-activated tritium atoms, and the resulting intramolecular distribution of the tritium label was analyzed to assess the steric accessibility of the amino acid residues in this protein. This technique revealed that interdomain loops and the C-terminal domain of the protein are the most accessible to labeling with tritium atoms. A model of the spatial arrangement of the C-terminal domain of matrix M1 protein was generated using rosetta software adjusted to the data obtained by tritium planigraphy experiments. This model suggests that the C-terminal domain is an almost flat layer with a three-α-helical structure. To explain the high level of tritium label incorporation into the C-terminal domain of the M1 protein in an acidic solution, we also used independent experimental approaches (CD spectroscopy, limited proteolysis and MALDI-TOF MS analysis of the proteolysis products, dynamic light scattering and analytical ultracentrifugation), as well as multiple computational algorithms, to analyse the intrinsic protein disorder. Taken together, the results obtained in the present study indicate that the C-terminal domain is weakly structured. We hypothesize that the specific 3D structural peculiarities of the M1 protein revealed in acidic pH solution allow the protein greater structural flexibility and enable it to interact effectively with the components of the host cell. © 2011 The Authors Journal compilation © 2011 FEBS.

  16. A biotin-drug extraction and acid dissociation (BEAD) procedure to eliminate matrix and drug interference in a protein complex anti-drug antibody (ADA) isotype specific assay.

    Science.gov (United States)

    Niu, Hongmei; Klem, Thomas; Yang, Jinsong; Qiu, Yongchang; Pan, Luying

    2017-07-01

    Monitoring anti-drug antibody (ADA) responses in patients receiving protein therapeutics treatment is an important safety assessment for regulatory agencies, drug manufacturers, clinicians and patients. Recombinant human IGF-1/IGFBP-3 (rhIGF-1/rhIGFBP-3) is a 1:1 formulation of naturally occurring protein complex. The individual IGF-1 and IGFBP-3 proteins have multiple binding partners in serum matrix with high binding affinity to each other, which presents challenges in ADA assay development. We have developed a biotin-drug extraction with acid dissociation (BEAD) procedure followed by an electrochemiluminescence (ECL) direct assay to overcome matrix and drug interference. The method utilizes two step acid dissociation and excess biotin-drug to extract total ADA, which are further captured by soluble biotin-drug and detected in an ECL semi-homogeneous direct assay format. The pre-treatment method effectively eliminates interference by serum matrix and free drug, and enhances assay sensitivity. The assays passed acceptance criteria for all validation parameters, and have been used for clinical sample Ab testing. This method principle exemplifies a new approach for anti-isotype ADA assays, and could be an effective strategy for neutralizing antibody (NAb), pharmacokinetic (PK) and biomarker analysis in need of overcoming interference factors. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Effects of heat stimulation and l-ascorbic acid 2-phosphate supplementation on myogenic differentiation of artificial skeletal muscle tissue constructs.

    Science.gov (United States)

    Ikeda, Kazushi; Ito, Akira; Sato, Masanori; Kanno, Shota; Kawabe, Yoshinori; Kamihira, Masamichi

    2017-05-01

    Although skeletal muscle tissue engineering has been extensively studied, the physical forces produced by tissue-engineered skeletal muscles remain to be improved for potential clinical utility. In this study, we examined the effects of mild heat stimulation and supplementation of a l-ascorbic acid derivative, l-ascorbic acid 2-phosphate (AscP), on myoblast differentiation and physical force generation of tissue-engineered skeletal muscles. Compared with control cultures at 37°C, mouse C2C12 myoblast cells cultured at 39°C enhanced myotube diameter (skeletal muscle hypertrophy), whereas mild heat stimulation did not promote myotube formation (differentiation rate). Conversely, AscP supplementation resulted in an increased differentiation rate but did not induce skeletal muscle hypertrophy. Following combined treatment with mild heat stimulation and AscP supplementation, both skeletal muscle hypertrophy and differentiation rate were enhanced. Moreover, the active tension produced by the tissue-engineered skeletal muscles was improved following combined treatment. These findings indicate that tissue culture using mild heat stimulation and AscP supplementation is a promising approach to enhance the function of tissue-engineered skeletal muscles. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  18. Tranexamic acid suppresses ultraviolet B eye irradiation-induced melanocyte activation by decreasing the levels of prohormone convertase 2 and alpha-melanocyte-stimulating hormone.

    Science.gov (United States)

    Hiramoto, Keiichi; Yamate, Yurika; Sugiyama, Daijiro; Takahashi, Yumi; Mafune, Eiichi

    2014-12-01

    Tranexamic acid (trans-4-aminomethylcyclohexanecarboxylic acid) is a medicinal amino acid used in skin whitening care. This study examined the effects of tranexamic acid on the melanocyte activation of the skin induced by an ultraviolet (UV) B eye irradiation. The eye or ear was locally exposed to UVB at a dose of 1.0 kJ/m(2) using a 20SE sunlamp after covering the remaining body surface with aluminum foil. UVB eye irradiation induced melanocyte activation of the skin, similar to that observed following UVB ear irradiation, which was suppressed by the administration of tranexamic acid treatment. The plasma α-melanocyte-stimulating hormone (α-MSH) content was increased by UVB irradiation of the eye; however, the increase in α-MSH was suppressed by tranexamic acid treatment. In addition, UVB eye irradiation induced the up-regulation of prohormone convertase (PC) 2 in the pituitary gland. Meanwhile, the increase in PC2 induced by UVB eye irradiation was suppressed by tranexamic acid treatment. These results clearly indicate that tranexamic acid decreases the expression of PC2, which cleavages from proopiomelanocortin to α-MSH in the pituitary gland, thereby suppressing melanocyte activation. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. [Fabrication of porous poly lactic acid-bone matrix gelatin composite bioactive material and its osteoinductive activity].

    Science.gov (United States)

    Zhang, Yumin; Li, Baoxing; Li, Ji

    2007-02-01

    To fabricate a novel porous bioactive composite biomaterial consisting of poly lactic acid (PLA)-bone matrix gelatin (BMG) by using the supercritical carbon dioxide fluid technique (SC-CO2) and to evaluate its osteoinductive activity. The cortical bones selected from healthy adult donors were processed into BMG by the defatting, demineralizing, and deproteinizing processes. PLA and BMG were mixed at a volume radio of 3 : 1; then, the PLA-BMG mixed material and the pure PLA material were respectively placed in the supercritical carbon dioxide reaction kettles, and were respectively added by the NaCl particles 100-200 microm in diameter for the porosity of the materials so that the porous PLA-BMG composite material and the porous PLA composite material could be formed. The mouse osteoblast-like MC3T3-E1 cells were cultured in the dulbecco's modified eagle medium (DMEM) supplemented with 10% fetal bovine serum. Then, 20 microl of the MC3T3-E1 cell suspensions containing 2 X 10(6) cells /ml were delivered into the culturing plate (24 wells/plate) made of the different materials, which were co-cultured for 2 weeks. In the PLA-BMG group, 100 microg of the crushed PLA-BMG material was contained in each well; in the PLA group, 100 microg of the crushed PLA material was contained in each well; and in the DMEM group, only DMEM was contained, which served as the control group. There were 6 wells in each group. The quantitative analysis on the calcification area was performed by the staining of the alizarin red S. The co-cultured cells were harvested and lysated in 1 ml of 0. 2% Nonidet P-40 by the ultrasonic lysating technique. Then, the ALP activity and the Ca content were measured according to the illuminations of the reagent kits. The porous PLA-BMG composite material showed a good homological porosity with a pore diameter of 50-150 microm and a good connectivity between the pores. The ALP activity, the Ca content, and the calcification area were significantly greater in

  20. Effects of hippocampal high-frequency electrical stimulation in memory formation and their association with amino acid tissue content and release in normal rats.

    Science.gov (United States)

    Luna-Munguía, Hiram; Meneses, Alfredo; Peña-Ortega, Fernando; Gaona, Andres; Rocha, Luisa

    2012-01-01

    Hippocampal high frequency electrical stimulation (HFS) at 130 Hz has been proposed as a therapeutical strategy to control neurological disorders such as intractable temporal lobe epilepsy (TLE). This study was carried out to determine the effects of hippocampal HFS on the memory process and the probable involvement of amino acids. Using the autoshaping task, we found that animals receiving hippocampal HFS showed augmented short-term, but not long-term memory formation, an effect blocked by bicuculline pretreatment and associated with enhanced tissue levels of amino acids in hippocampus. In addition, microdialysis experiments revealed high extracellular levels of glutamate, aspartate, glycine, taurine, and alanine during the application of hippocampal HFS. In contrast, GABA release augmented during HFS and remained elevated for more than 1 h after the stimulation was ended. HFS had minimal effects on glutamine release. The present results suggest that HFS has an activating effect on specific amino acids in normal hippocampus that may be involved in the enhanced short-term memory formation. These data further provide experimental support for the concept that hippocampus may be a promising target for focal stimulation to treat intractable seizures in humans. Copyright © 2010 Wiley Periodicals, Inc., Inc.

  1. Influence of the composition of hydroxypropyl cellulose/maleic acid-alt-styrene copolymer blends on their properties as matrix for drug release

    Directory of Open Access Journals (Sweden)

    2009-05-01

    Full Text Available Poly(carboxylic acid-polysaccharide compositions have been found suitable for obtaining drug formulations with controlled release, most formulations being therapeutically efficacious, stable, and non-irritant. The influence of the characteristics of the aqueous solutions from which the polymer matrix is prepared (i.e. the total concentration of polymer in solutions and the mixing ratio between the partners, hydroxypropyl cellulose, HPC and maleic acid-alternating-styrene copolymer, MAc-alt-S on the kinetics of some drugs release in acidic environment (pH = 2 has been followed by ‘in vitro’ dissolution tests. It has been established that the kinetics of procaine hydrochloride release from HPC/MAc-alt-S matrix depends on its composition; the diffusion exponent, n is close to 0.5 for matrices where one of the components is in large excess and n~0.02 for middle composition range. The lower value of diffusion exponent for middle composition range could be caused by the so called ‘burst effect’, therefore the kinetic evaluation is difficult.

  2. Ammonia-treated N-(1-naphthyl) ethylenediamine dihydrochloride as a novel matrix for rapid quantitative and qualitative determination of serum free fatty acids by matrix-assisted laser desorption/ionization-Fourier transform ion cyclotron resonance mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yaping [Department of Biophysics and Structural Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, 5 Dongdan San Tiao, Beijing 100005 (China); Wang, Yanmin [Department of Clinical Laboratory, Heze Municipal Hospital, Shandong (China); Guo, Shuai; Guo, Yumei; Liu, Hui [Department of Biophysics and Structural Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, 5 Dongdan San Tiao, Beijing 100005 (China); Li, Zhili, E-mail: lizhili@ibms.pumc.edu.cn [Department of Biophysics and Structural Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, 5 Dongdan San Tiao, Beijing 100005 (China)

    2013-09-10

    Graphical abstract: -- Highlights: •A novel MALDI matrix for the detection of serum free fatty acids is ammonia-treated N-(1-naphthyl) ethylenediamine dihydrochloride. •Multiple point internal standard calibration curves were constructed for nine FFAs, respectively, with excellent correlation coefficients between 0.991 and 0.999. •The MALDI-MS approach was used to rapidly differentiate the patients with and without hyperglycemia and healthy controls. -- Abstract: The blood free fatty acids (FFAs), which provide energy to the cell and act as substrates in the synthesis of fats, lipoproteins, liposaccharides, and eicosanoids, involve in a number of important physiological processes. In the present study, matrix-assisted laser desorption/ionization-Fourier transform ion cyclotron resonance mass spectrometry (MALDI-FTICR MS) with ammonia-treated N-(1-naphthyl) ethylenediamine dihydrochloride (ATNEDC) as a novel MALDI matrix in a negative ion mode was employed to directly quantify serum FFAs. Multiple point internal standard calibration curves between the concentration ratios of individual fatty acids to internal standard (IS, C{sub 17:0}) versus their corresponding intensity ratios were constructed for C{sub 14:0}, C{sub 16:1}, C{sub 16:0}, C{sub 18:0}, C{sub 18:1}, C{sub 18:2}, C{sub 18:3}, C{sub 20:4}, and C{sub 22:6}, respectively, in their mixture, with correlation coefficients between 0.991 and 0.999 and limits of detection (LODs) between 0.2 and 5.4 μM, along with the linear dynamic range of more than two orders of magnitude. The results indicate that the multiple point internal standard calibration could reduce the impact of ion suppression and improve quantification accuracy in the MALDI mode. The quantitative results of nine FFAs from 339 serum samples, including 161 healthy controls, 118 patients with hyperglycemia and 60 patients without hyperglycemia show that FFAs levels in hyperglycemic patient sera are significantly higher than those in healthy

  3. Ammonia-treated N-(1-naphthyl) ethylenediamine dihydrochloride as a novel matrix for rapid quantitative and qualitative determination of serum free fatty acids by matrix-assisted laser desorption/ionization-Fourier transform ion cyclotron resonance mass spectrometry

    International Nuclear Information System (INIS)

    Zhang, Yaping; Wang, Yanmin; Guo, Shuai; Guo, Yumei; Liu, Hui; Li, Zhili

    2013-01-01

    Graphical abstract: -- Highlights: •A novel MALDI matrix for the detection of serum free fatty acids is ammonia-treated N-(1-naphthyl) ethylenediamine dihydrochloride. •Multiple point internal standard calibration curves were constructed for nine FFAs, respectively, with excellent correlation coefficients between 0.991 and 0.999. •The MALDI-MS approach was used to rapidly differentiate the patients with and without hyperglycemia and healthy controls. -- Abstract: The blood free fatty acids (FFAs), which provide energy to the cell and act as substrates in the synthesis of fats, lipoproteins, liposaccharides, and eicosanoids, involve in a number of important physiological processes. In the present study, matrix-assisted laser desorption/ionization-Fourier transform ion cyclotron resonance mass spectrometry (MALDI-FTICR MS) with ammonia-treated N-(1-naphthyl) ethylenediamine dihydrochloride (ATNEDC) as a novel MALDI matrix in a negative ion mode was employed to directly quantify serum FFAs. Multiple point internal standard calibration curves between the concentration ratios of individual fatty acids to internal standard (IS, C 17:0 ) versus their corresponding intensity ratios were constructed for C 14:0 , C 16:1 , C 16:0 , C 18:0 , C 18:1 , C 18:2 , C 18:3 , C 20:4 , and C 22:6 , respectively, in their mixture, with correlation coefficients between 0.991 and 0.999 and limits of detection (LODs) between 0.2 and 5.4 μM, along with the linear dynamic range of more than two orders of magnitude. The results indicate that the multiple point internal standard calibration could reduce the impact of ion suppression and improve quantification accuracy in the MALDI mode. The quantitative results of nine FFAs from 339 serum samples, including 161 healthy controls, 118 patients with hyperglycemia and 60 patients without hyperglycemia show that FFAs levels in hyperglycemic patient sera are significantly higher than those in healthy controls and patients without

  4. Study of matrix effects on the direct trace analysis of acidic pesticides in water using various liquid chromatographic modes coupled to tandem mass spectrometric detection.

    Science.gov (United States)

    Dijkman, E; Mooibroek, D; Hoogerbrugge, R; Hogendoorn, E; Sancho, J V; Pozo, O; Hernández, F

    2001-08-10

    This study investigated the effects of matrix interferences on the analytical performance of a triple quadrupole mass spectrometric (MS-MS) detector coupled to various reversed-phase liquid chromatographic (LC) modes for the on-line determination of various types of acidic herbicides in water using external calibration for quantification of the analytes tested at a level of 0.4 microg/l. The LC modes included (i) a single-column configuration (LC), (ii) precolumn switching (PC-LC) and (iii) coupled-column LC (LC-LC). As regards detection, electrospray (ESI) and atmospheric pressure chemical ionization (APCI) in both positive (PI) and negative (NI) ionization modes were examined. Salinity and dissolved organic carbon (DOC) were selected as interferences to study matrix effects in this type of analysis. Therefore, Milli-Q and tap water samples both fortified with 12 mg/l DOC and spiked with sulfometuron-methyl, bentazone, bromoxynil, 2-methyl-4-chlorophenoxyacetic acid, and 2-methyl-4-chlorophenoxypropionic acid at a level of about 0.4 microg/l were analyzed with the various LC-MS approaches. Direct sample injection was performed with volumes of 0.25 ml or 2.0 ml on a column of 2.1 mm I.D. or 4.6 mm I.D. for the ESI and APCI modes, respectively. The recovery data were used to compare and evaluate the analytical performance of the various LC approaches. As regards matrix effects, the salinity provided a dramatic decrease in response for early eluting analytes (k value of about 1) when using the LC mode. Both PC-LC and LC-LC efficiently eliminated this problem. The high DOC content hardly effected the responses of analytes in the ESI mode, while in most cases the responses increased when using APCI-MS-MS detection. Of all the tested configurations, LC-LC-ESI-MS-MS with the column combination Discovery C18/ABZ+ was the most favorable as regards elimination of matrix effects and provided reliable quantification of all compounds using external calibration at the tested

  5. Application of response surface methodology in optimization of lactic acid fermentation of radish: effect of addition of salt, additives and growth stimulators.

    Science.gov (United States)

    Joshi, V K; Chauhan, Arjun; Devi, Sarita; Kumar, Vikas

    2015-08-01

    Lactic acid fermentation of radish was conducted using various additive and growth stimulators such as salt (2 %-3 %), lactose, MgSO4 + MnSO4 and Mustard (1 %, 1.5 % and 2 %) to optimize the process. Response surface methodology (Design expert, Trial version 8.0.5.2) was applied to the experimental data for the optimization of process variables in lactic acid fermentation of radish. Out of various treatments studied, only the treatments having ground mustard had an appreciable effect on lactic acid fermentation. Both linear and quadratic terms of the variables studied had a significant effect on the responses studied. The interactions between the variables were found to contribute to the response at a significant level. The best results were obtained in the treatment with 2.5 % salt, 1.5 % lactose, 1.5 % (MgSO4 + MnSO4) and 1.5 % mustard. These optimized concentrations increased titrable acidity and LAB count, but lowered pH. The second-order polynomial regression model determined that the highest titrable acidity (1.69), lowest pH (2.49) and maximum LAB count (10 × 10(8) cfu/ml) would be obtained at these concentrations of additives. Among 30 runs conducted, run 2 has got the optimum concentration of salt- 2.5 %, lactose- 1.5 %, MgSO4 + MnSO4- 1.5 % and mustard- 1.5 % for lactic acid fermentation of radish. The values for different additives and growth stimulators optimized in this study could successfully be employed for the lactic acid fermentation of radish as a postharvest reduction tool and for product development.

  6. The H1 histone-specific proteinase is associated with nuclear matrix and stimulated by DNA containing breaks of denatured sites

    International Nuclear Information System (INIS)

    Gaziev, A.I.; Kutsyj, M.P.

    1988-01-01

    Discovery of proteinase in nuclear matrix specific of H1 histone and dependent presence of breaks or denatured sites in DNA permits to assume that the given enzyme, obviously, participates in replication and DNA repair, in regulation of genes expression. Removal of H1 histone by proteinase is, probably, necessary for procedure of these processes, and, obviously, this proteinase suffers conformational changes in the composition of the DNA-histone complex. H1 histone disintegration in nucleohistone containing damaged sites of DNA by specific proteinase, probably, represents one of the mechanisms for providing DNA repair in cells of higher organisms

  7. GLYCOLIC-NITRIC ACID FLOWSHEET DEMONSTRATION OF THE DWPF CHEMICAL PROCESSING CELL WITH MATRIX SIMULANTS AND SUPERNATE

    Energy Technology Data Exchange (ETDEWEB)

    Lambert, D.; Stone, M.; Newell, J.; Best, D.

    2012-05-07

    Savannah River Remediation (SRR) is evaluating changes to its current DWPF flowsheet to improve processing cycle times. This will enable the facility to support higher canister production while maximizing waste loading. Higher throughput is needed in the CPC since the installation of the bubblers into the melter has increased melt rate. Due to the significant maintenance required for the DWPF gas chromatographs (GC) and the potential for production of flammable quantities of hydrogen, reducing or eliminating the amount of formic acid used in the CPC is being developed. Earlier work at Savannah River National Laboratory has shown that replacing formic acid with an 80:20 molar blend of glycolic and formic acids has the potential to remove mercury in the SRAT without any significant catalytic hydrogen generation. This report summarizes the research completed to determine the feasibility of processing without formic acid. In earlier development of the glycolic-formic acid flowsheet, one run (GF8) was completed without formic acid. It is of particular interest that mercury was successfully removed in GF8, no formic acid at 125% stoichiometry. Glycolic acid did not show the ability to reduce mercury to elemental mercury in initial screening studies, which is why previous testing focused on using the formic/glycolic blend. The objective of the testing detailed in this document is to determine the viability of the nitric-glycolic acid flowsheet in processing sludge over a wide compositional range as requested by DWPF. This work was performed under the guidance of Task Technical and Quality Assurance Plan (TT and QAP). The details regarding the simulant preparation and analysis have been documented previously.

  8. Stimulation des réservoirs gréseux. Interprétation des courbes de réponse à l'acide Sandstone Acidizing. Acid Response Curves Interpretation

    Directory of Open Access Journals (Sweden)

    Labrid J.

    2006-11-01

    Full Text Available Les problèmes d'acidification des réservoirs gréseux sont abordés en introduisant une grandeur cinétique caractéristique du milieu à stimuler appelée réactivité dont la détermination est nécessaire pour l'interprétation complète des courbes de réponse à l'acide; ce concept de réactivité prend en compte la morphologie du milieu poreux (dimension et forme des- grains, distribution des minéraux, et les constantes de vitesse de dissolution des différentes espèces minéralogiques. Les effets de l'acidification sont évalués en établissant une relation liant la porosité, la perméabilité et la réactivité; cette relation est indépendante des conditions de l'expérience : débit, concentration et volume d'acide injecté. Par ailleurs, un modèle mathématique de l'acidification a été conçu et mis au point en géométrie radiale et unidimensionnelle. Ce modèle, alimenté par les données tirées de l'expérience, restitue de manière très satisfaisante l'évolution des propriétés pétrophysiqués du milieu ; son application à la géométrie radiale (cas de l'opération de chantier conduit à des recommandations sur la procédure à adopter en fonction des caractéristiques de la formation. Problems in the acid treatment of sandstone reservoirs are approached by introducing a kinetic parameter, called reactivity, thot is characteristic of the medium to be stimulated. This reactivity must be determined fora complete interpretation of the acid response curves. The concept of reactivity tokes into consideration the morphology of the porous medium (grain size and shape, distribution of minerals and the dissolution rate constants of the différent mineralogical species. The effects of acid treatment are evaluated by establishing a relationship linking porosity, permeability and reactivity. This relationship is independent of the experimental conditions such as flowrate and concentration and volume of acid injected. In

  9. Age Differences of Salivary Alpha-Amylase Levels of Basal and Acute Responses to Citric Acid Stimulation Between Chinese Children and Adults.

    Science.gov (United States)

    Yang, Ze-Min; Chen, Long-Hui; Zhang, Min; Lin, Jing; Zhang, Jie; Chen, Wei-Wen; Yang, Xiao-Rong

    2015-01-01

    It remains unclear how salivary alpha-amylase (sAA) levels respond to mechanical stimuli in different age groups. In addition, the role played by the sAA gene (AMY1) copy number and protein expression (glycosylated and non-glycosylated) in sAA activity has also been rarely reported. In this study, we analyzed saliva samples collected before and after citric acid stimulation from 47 child and 47 adult Chinese subjects. We observed that adults had higher sAA activity and sAA glycosylated levels (glycosylated sAA amount/total sAA amount) in basal and stimulated saliva when compared with children, while no differences were found in total or glycosylated sAA amount between them. Interestingly, adults showed attenuated sAA activity levels increase over those of children after stimulation. Correlation analysis showed that total sAA amount, glycosylated sAA amount, and AMY1 copy number × total sAA amount were all positively correlated with sAA activity before and after stimulation in both groups. Interestingly, correlation r between sAA levels (glycosylated sAA amount and total sAA amount) and sAA activity decreased after stimulation in children, while adults showed an increase in correlation r. In addition, the correlation r between AMY1 copy number × total sAA amount and sAA activity was higher than that between AMY1 copy number, total sAA amount, and sAA activity, respectively. Taken together, our results suggest that total sAA amount, glycosylated sAA amount, and the positive interaction between AMY1 copy number and total sAA amount are crucial in influencing sAA activity before and after stimulation in children and adults.

  10. Age differences of salivary alpha-amylase levels of basal and acute responses to citric acid stimulation between Chinese children and adults

    Directory of Open Access Journals (Sweden)

    Zemin eYang

    2015-11-01

    Full Text Available It remains unclear how salivary alpha-amylase (sAA levels respond to mechanical stimuli in different age groups. In addition, the role played by the sAA gene (AMY1 copy number and protein expression (glycosylated and non-glycosylated in sAA activity has also been rarely reported. In this study, we analyzed saliva samples collected before and after citric acid stimulation from 47 child and 47 adult Chinese subjects. We observed that adults had higher sAA activity and sAA glycosylated levels (glycosylated sAA amount/total sAA amount in basal and stimulated saliva when compared with children, while no differences were found in total or glycosylated sAA amount between them. Interestingly, adults showed attenuated sAA activity levels increase over those of children after stimulation. Correlation analysis showed that total sAA amount, glycosylated sAA amount, and AMY1 copy number×total sAA amount were all positively correlated with sAA activity before and after stimulation in both groups. Interestingly, correlation r between sAA levels (glycosylated sAA amount and total sAA amount and sAA activity decreased after stimulation in children, while adults showed an increase in correlation r. In addition, the correlation r between AMY1 copy number×total sAA amount and sAA activity was higher than that between AMY1 copy number, total sAA amount and sAA activity, respectively. Taken together, our results suggest that total sAA amount, glycosylated sAA amount, and the positive interaction between AMY1 copy number and total sAA amount are crucial in influencing sAA activity before and after stimulation in children and adults.

  11. Mixed-matrix membranes with enhanced antifouling activity: probing the surface-tailoring potential of Tiron and chromotropic acid for nano-TiO2

    Science.gov (United States)

    Pal, Avishek; Dey, T. K.; Debnath, A. K.; Bhushan, Bharat; Sahu, A. K.; Bindal, R. C.; Kar, Soumitra

    2017-09-01

    Mixed-matrix membranes (MMMs) were developed by impregnating organofunctionalized nanoadditives within fouling-susceptible polysulfone matrix following the non-solvent induced phase separation (NIPS) method. The facile functionalization of nanoparticles of anatase TiO2 (nano-TiO2) by using two different organoligands, viz. Tiron and chromotropic acid, was carried out to obtain organofunctionalized nanoadditives, FT-nano-TiO2 and FC-nano-TiO2, respectively. The structural features of nanoadditives were evaluated by X-ray diffraction, X-ray photoelectron spectroscopy, Raman and Fourier transform infrared spectroscopy, which established that Tiron leads to the blending of chelating and bridging bidentate geometries for FT-nano-TiO2, whereas chromotropic acid produces bridging bidentate as well as monodentate geometries for FC-nano-TiO2. The surface chemistry of the studied membranes, polysulfone (Psf): FT-nano-TiO2 UF and Psf: FC-nano-TiO2 UF, was profoundly influenced by the benign distributions of the nanoadditives enriched with distinctly charged sites (-SO3 -H+ ), as evidenced by superior morphology, improved topography, enhanced surface hydrophilicity and altered electrokinetic features. The membranes exhibited enhanced solvent throughputs, viz. 3500-4000 and 3400-4300 LMD at 1 bar of transmembrane pressure, without significant compromise in their rejection attributes. The flux recovery ratios and fouling resistive behaviours of MMMs towards bovine serum albumin indicated that the nanoadditives could impart stable and appreciable antifouling activity, potentially aiding in a sustainable ultrafiltration performance.

  12. Uric acid stimulates proliferative pathways in vascular smooth muscle cells through the activation of p38 MAPK, p44/42 MAPK and PDGFRβ.

    Science.gov (United States)

    Kırça, M; Oğuz, N; Çetin, A; Uzuner, F; Yeşilkaya, A

    2017-04-01

    Hyperuricemia and angiotensin II (Ang II) may have a pathogenetic role in the development of hypertension and atherosclerosis as well as cardiovascular disease (CVD) and its prognosis. The purpose of this study was to investigate whether uric acid can induce proliferative pathways of vascular smooth muscle cell (VSMC) that are thought to be responsible for the development of CVD. The phosphorylation of p38 mitogen-activated protein kinase (p38 MAPK), p44/42 mitogen-activated protein kinase (p44/42 MAPK) and platelet-derived growth factor receptor β (PDGFRβ) was measured by Elisa and Western blot techniques to determine the activation of proliferative pathways in primary cultured VSMCs from rat aorta. Results demonstrated that uric acid can stimulate p38 MAPK, p44/42 MAPK and PDGFRβ phosphorylation in a time- and concentration-dependent manner. Furthermore, treatment of VSMCs with the angiotensin II type I receptor (AT1R) inhibitor losartan suppressed p38 MAPK and p44/42 MAPK induction by uric acid. The stimulatory effect of uric acid on p38 MAPK was higher compared to that of Ang II. The results of this study show for the first time that uric acid-induced PDGFRβ phosphorylation plays a crucial role in the development of CVDs and that elevated uric acid levels could be a potential therapeutical target in CVD patients.

  13. Reevaluation of Fatty acid receptor 1 (FFAR1/GPR40) as drug target for the stimulation of insulin secretion in humans

    DEFF Research Database (Denmark)

    Wagner, Robert; Kaiser, Gabriele; Gerst, Felicia

    2013-01-01

    The role of free fatty acid receptor 1 (FFAR1/GPR40) in glucose homeostasis is still incompletely understood. Small receptor agonists stimulating insulin secretion are under investigation for the treatment of type 2 diabetes. Surprisingly, genome-wide association studies did not discover diabetes...... risk variants in FFAR1. We reevaluated the role of FFAR1 in insulin secretion using a specific agonist, FFAR1-knockout mice and human islets. Nondiabetic individuals were metabolically phenotyped and genotyped. In vitro experiments indicated that palmitate and a specific FFAR1-agonist, TUG-469......, stimulate glucose-induced insulin secretion through FFAR1. The pro-apoptotic effect of chronic exposure of beta-cells to palmitate was independent of FFAR1. TUG-469 was protective, while inhibition of FFAR1 promoted apoptosis. In accordance with the pro-apoptotic effect of palmitate, in vivo crosssectional...

  14. An immunofluorescence assay for extracellular matrix components highlights the role of epithelial cells in producing a stable, fibrillar extracellular matrix

    Directory of Open Access Journals (Sweden)

    Omar S. Qureshi

    2017-10-01

    Full Text Available Activated fibroblasts are considered major drivers of fibrotic disease progression through the production of excessive extracellular matrix (ECM in response to signals from damaged epithelial and inflammatory cells. Nevertheless, epithelial cells are capable of expressing components of the ECM, cross-linking enzymes that increase its stability and are sensitive to factors involved in the early stages of fibrosis. We therefore wanted to test the hypothesis that epithelial cells can deposit ECM in response to stimulation in a comparable manner to fibroblasts. We performed immunofluorescence analysis of components of stable, mature extracellular matrix produced by primary human renal proximal tubular epithelial cells and renal fibroblasts in response to cytokine stimulation. Whilst fibroblasts produced a higher basal level of extracellular matrix components, epithelial cells were able to deposit significant levels of fibronectin, collagen I, III and IV in response to cytokine stimulation. In response to hypoxia, epithelial cells showed an increase in collagen IV deposition but not in response to the acute stress stimuli aristolochic acid or hydrogen peroxide. When epithelial cells were in co-culture with fibroblasts we observed significant increases in the level of matrix deposition which could be reduced by transforming growth factor beta (TGF-β blockade. Our results highlight the role of epithelial cells acting as efficient producers of stable extracellular matrix which could contribute to renal tubule thickening in fibrosis.

  15. High Leucine Diets Stimulate Cerebral Branched-Chain Amino Acid Degradation and Modify Serotonin and Ketone Body Concentrations in a Pig Model

    Science.gov (United States)

    Wessels, Anna G.; Kluge, Holger; Hirche, Frank; Kiowski, Andreas; Schutkowski, Alexandra; Corrent, Etienne; Bartelt, Jörg; König, Bettina; Stangl, Gabriele I.

    2016-01-01

    In addition to its role as an essential protein component, leucine (Leu) displays several other metabolic functions such as activation of protein synthesis. This property makes it an interesting amino acid for the therapy of human muscle atrophy and for livestock production. However, Leu can stimulate its own degradation via the branched-chain keto acid dehydrogenase complex (BCKDH). To examine the response of several tissues to excessive Leu, pigs were fed diets containing two- (L2) and four-fold (L4) higher Leu contents than the recommended amount (control). We found that the L4 diet led to a pronounced increase in BCKDH activity in the brain (2.5-fold, P diet had only weak effects on BCKDH activity. Both high Leu diets reduced the concentrations of free valine and isoleucine in nearly all tissues. In the brain, high Leu diets modified the amount of tryptophan available: for serotonin synthesis. Compared to the controls, pigs treated with the high Leu diets consumed less food, showed increased plasma concentrations of 3-hydroxybutyrate and reduced levels of circulating serotonin. In conclusion, excessive Leu can stimulate BCKDH activity in several tissues, including the brain. Changes in cerebral tryptophan, along with the changes in amino acid-derived metabolites in the plasma may limit the use of high Leu diets to treat muscle atrophy or to increase muscle growth. PMID:26930301

  16. Induction of activator protein (AP)-1 and nuclear factor-kappaB by CD28 stimulation involves both phosphatidylinositol 3-kinase and acidic sphingomyelinase signals.

    Science.gov (United States)

    Edmead, C E; Patel, Y I; Wilson, A; Boulougouris, G; Hall, N D; Ward, S G; Sansom, D M

    1996-10-15

    A major obstacle in understanding the signaling events that follow CD28 receptor ligation arises from the fact that CD28 acts as a costimulus to TCR engagement, making it difficult to assess the relative contribution of CD28 signals as distinct from those of the TCR. To overcome this problem, we have exploited the observation that activated human T cell blasts can be stimulated via the CD28 surface molecule in the absence of antigenic challenge; thus, we have been able to observe the response of normal T cells to CD28 activation in isolation. Using this system, we observed that CD28 stimulation by B7-transfected CHO cells induced a proliferative response in T cells that was not accompanied by measurable IL-2 production. However, subsequent analysis of transcription factor generation revealed that B7 stimulation induced both activator protein-1 (AP-1) and nuclear factor-kappaB (NF-kappaB) complexes, but not NF-AT. In contrast, engagement of the TCR by class II MHC/superantigen, either with or without CD28 ligation, resulted in the induction of NF-AT, AP-1, and NF-kappaB as well as IL-2 production. Using selective inhibitors, we investigated the signaling pathways involved in the CD28-mediated induction of AP-1 and NF-kappaB. This revealed that NF-kappaB generation was sensitive to chloroquine, an inhibitor of acidic sphingomyelinase, but not to the phosphatidylinositol 3-kinase inhibitor, wortmannin. In contrast, AP-1 generation was inhibited by wortmannin and was also variably sensitive to chloroquine. These data suggest that in activated normal T cells, CD28-derived signals can stimulate proliferation at least in part via NF-kappaB and AP-1 generation, and that this response uses both acidic sphingomyelinase and phosphatidylinositol 3-kinase-linked pathways.

  17. Overexpression of membrane sialic acid-specific sialidase Neu3 inhibits matrix metalloproteinase-9 expression in vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Moon, Sung-Kwon; Cho, Seung-Hak; Kim, Kyung-Woon; Jeon, Jae Heung; Ko, Jeong-Heon; Kim, Bo Yeon; Kim, Cheorl-Ho

    2007-01-01

    The ganglioside-specific sialidase Neu3 has been suggested to participate in cell growth, migration, and differentiation. Recent reports suggest that sialidase may be involved in intimal thickening, an early stage in the development of atherosclerosis. However, the role of the Neu3 gene in vascular smooth muscle cells (VSMC) responses has not yet been elucidated. To determine whether a Neu3 is able to modulate VSMC growth, the effect of overexpression of the Neu3 gene on cell proliferation was examined. However, the results show that the overexpression of this gene has no effect on DNA synthesis and ERK phosphorylation in cultured VSMC in the presence of TNF-α. Because atherogenic effects need not be limited to proliferation, we decided to examine whether Neu3 exerted inhibitory effects on matrix metalloproteinase-9 (MMP-9) activity in TNF-α-induced VSMC. The expression of the Neu3 gene led to the inhibition of TNF-α-induced matrix metalloproteinase-9 (MMP-9) expression in VSMC as determined by zymography and immunoblot. Furthermore, Neu3 gene expression strongly decreased MMP-9 promoter activity in response to TNF-α. This inhibition was characterized by the down-regulation of MMP-9, which was transcriptionally regulated at NF-κB and activation protein-1 (AP-1) sites in the MMP-9 promoter. These findings suggest that the Neu3 gene represents a physiological modulator of VSMC responses that may contribute to plaque instability in atherosclerosis

  18. Performance of Different Acids on Sandstone Formations

    Directory of Open Access Journals (Sweden)

    M. A. Zaman

    2013-12-01

    Full Text Available Stimulation of sandstone formations is a challenging task, which involves several chemicals and physical interactions of the acid with the formation. Some of these reactions may result in formation damage. Mud acid has been successfully used to stimulate sandstone reservoirs for a number of years. It is a mixture of hydrofluoric (HF and hydrochloric (HCl acids designed to dissolve clays and siliceous fines accumulated in the near-wellbore region. Matrix acidizing may also be used to increase formation permeability in undamaged wells. The change may be up to 50% to 100% with the mud acid. For any acidizing process, the selection of acid (Formulation and Concentration and the design (Pre-flush, Main Acid, After-flush is very important. Different researchers are using different combinations of acids with different concentrations to get the best results for acidization. Mainly the common practice is combination of Hydrochloric Acid – Hydrofluoric with Concentration (3% HF – 12% HCl. This paper presents the results of a laboratory investigation of Orthophosphoric acid instead of hydrochloric acid in one combination and the second combination is Fluoboric and formic acid and the third one is formic and hydrofluoric acid. The results are compared with the mud acid and the results calculated are porosity, permeability, and FESEM Analysis and Strength tests. All of these new combinations shows that these have the potential to be used as acidizing acids on sandstone formations.

  19. The existence of an insulin-stimulated glucose and non-essential but not essential amino acid substrate interaction in diabetic pigs

    Directory of Open Access Journals (Sweden)

    Wijdenes Jan

    2011-05-01

    Full Text Available Abstract Background The generation of energy from glucose is impaired in diabetes and can be compensated by other substrates like fatty acids (Randle cycle. Little information is available on amino acids (AA as alternative energy-source in diabetes. To study the interaction between insulin-stimulated glucose and AA utilization in normal and diabetic subjects, intraportal hyperinsulinaemic euglycaemic euaminoacidaemic clamp studies were performed in normal (n = 8 and streptozotocin (120 mg/kg induced diabetic (n = 7 pigs of ~40-45 kg. Results Diabetic vs normal pigs showed basal hyperglycaemia (19.0 ± 2.0 vs 4.7 ± 0.1 mmol/L, P P P P P P P . Essential AA clearance was largely unchanged (72.9 ± 8.5 vs 63.3 ± 8.5 mL/kg· min, however clearances of threonine (P P Conclusions The ratio of insulin-stimulated glucose versus AA clearance was decreased 5.4-fold in diabetic pigs, which was caused by a 3.6-fold decrease in glucose clearance and a 2.0-fold increase in non-essential AA clearance. In parallel with the Randle concept (glucose - fatty acid cycle, the present data suggest the existence of a glucose and non-essential AA substrate interaction in diabetic pigs whereby reduced insulin-stimulated glucose clearance seems to be partly compensated by an increase in non-essential AA clearance whereas essential AA are preferentially spared from an increase in clearance.

  20. Effects of spray-drying on w/o/w multiple emulsions prepared from a stearic acid matrix

    CSIR Research Space (South Africa)

    Mlalila, N

    2014-12-01

    Full Text Available , 75, and 100 mg of stearic acid, 2% and 3% w/v polyvinyl alcohol, 5% w/v lactose, and 0.2% w/v chitosan. The emulsions were immediately spray-dried based on an optimized model of inlet temperature and pump rate, and characterized for optimized...

  1. Beneficial effects of retinoic acid on extracellular matrix degradation and attachment behaviour in follicular thyroid carcinoma cell lines

    NARCIS (Netherlands)

    Havekes, B.; Schröder van der Elst, J. P.; van der Pluijm, G.; Goslings, B. M.; Romijn, J. A.; Smit, J. W.

    2000-01-01

    The prognosis of patients with metastasised follicular thyroid carcinoma (FTC) is limited, necessitating the search for new treatment options. Beneficial effects of retinoids have been suggested in thyroid cancer and the present study was performed to investigate the effects of retinoic acid (RA) on

  2. Correction of a splice-site mutation in the beta-globin gene stimulated by triplex-forming peptide nucleic acids

    DEFF Research Database (Denmark)

    Chin, Joanna Y; Kuan, Jean Y; Lonkar, Pallavi S

    2008-01-01

    Splice-site mutations in the beta-globin gene can lead to aberrant transcripts and decreased functional beta-globin, causing beta-thalassemia. Triplex-forming DNA oligonucleotides (TFOs) and peptide nucleic acids (PNAs) have been shown to stimulate recombination in reporter gene loci in mammalian...... DNA fragments, can promote single base-pair modification at the start of the second intron of the beta-globin gene, the site of a common thalassemia-associated mutation. This single base pair change was detected by the restoration of proper splicing of transcripts produced from a green fluorescent...

  3. Occurrence of postmenopausal-like acidic follicle-stimulating hormone (FSH) isoforms precedes the rise of FSH before menopause.

    NARCIS (Netherlands)

    Thomas, C.M.G.; Span, P.N.; Smeenk, J.M.J.; Hanssen, R.G.; Braat, D.D.M.; Sweep, F.C.

    2009-01-01

    OBJECTIVE: To assess the glycoform distribution patterns of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) during the menstrual cycle at different ages and FSH levels, after menopause, and with premature ovarian failure (POF). DESIGN: Controlled clinical study. SETTING: Healthy

  4. Profiling the Fatty Acids Content of Ornamental Camellia Seeds Cultivated in Galicia by an Optimized Matrix Solid-Phase Dispersion Extraction

    Directory of Open Access Journals (Sweden)

    Carmen Garcia-Jares

    2017-10-01

    Full Text Available Camellia (genus of flowering plants of fam. Theaceae is one of the main crops in Asia, where tea and oil from leaves and seeds have been utilized for thousands of years. This plant is excellently adapted to the climate and soil of Galicia (northwestern Spain and northern Portugal where it is grown not only as an ornamental plant, but to be evaluated as a source of bioactive compounds. In this work, the main fatty acids were extracted from Camellia seeds of four varieties of Camellia: sasanqua, reticulata, japonica and sinensis, by means of matrix-solid phase dispersion (MSPD, and analyzed by gas chromatography (GC with MS detection of the corresponding methyl esters. MSPD constitutes an efficient and greener alternative to conventional extraction techniques, moreover if it is combined with the use of green solvents such as limonene. The optimization of the MSPD extraction procedure has been conducted using a multivariate approach based on strategies of experimental design, which enabled the simultaneous evaluation of the factors influencing the extraction efficiency as well as interactions between factors. The optimized method was applied to characterize the fatty acids profiles of four Camellia varieties seeds, allowing us to compare their fatty acid composition.

  5. Profiling the Fatty Acids Content of Ornamental Camellia Seeds Cultivated in Galicia by an Optimized Matrix Solid-Phase Dispersion Extraction

    Science.gov (United States)

    Garcia-Jares, Carmen; Sanchez-Nande, Marta; Lamas, Juan Pablo; Lores, Marta

    2017-01-01

    Camellia (genus of flowering plants of fam. Theaceae) is one of the main crops in Asia, where tea and oil from leaves and seeds have been utilized for thousands of years. This plant is excellently adapted to the climate and soil of Galicia (northwestern Spain) and northern Portugal where it is grown not only as an ornamental plant, but to be evaluated as a source of bioactive compounds. In this work, the main fatty acids were extracted from Camellia seeds of four varieties of Camellia: sasanqua, reticulata, japonica and sinensis, by means of matrix-solid phase dispersion (MSPD), and analyzed by gas chromatography (GC) with MS detection of the corresponding methyl esters. MSPD constitutes an efficient and greener alternative to conventional extraction techniques, moreover if it is combined with the use of green solvents such as limonene. The optimization of the MSPD extraction procedure has been conducted using a multivariate approach based on strategies of experimental design, which enabled the simultaneous evaluation of the factors influencing the extraction efficiency as well as interactions between factors. The optimized method was applied to characterize the fatty acids profiles of four Camellia varieties seeds, allowing us to compare their fatty acid composition. PMID:29039745

  6. Lignite pre-treatment and its effect on bio-stimulative properties of respective lignite humic acids

    Energy Technology Data Exchange (ETDEWEB)

    Vlckova, Z.; Grasset, L.; Antosova, B.; Pekar, M.; Kucerik, J. [Brno University of Technology, Brno (Czech Republic). Faculty of Chemistry

    2009-09-15

    Humic acids originating from South-Moravian lignite were subjected to a comparative study with the aim to assess the alteration of their physico-chemical properties after various lignite pre-treatments. Physical modification was achieved with two organic acids, such as acetic acid and citric acid and chemical modification by nitric acid and hydrogene peroxide in various concentrations. Elemental analysis, solid-state NMR, GC-MS analysis of polyols and size exclusion chromatography were carried out for chemical-physical characterization of obtained humic acids. Their biological effect, in form of potassium and ammonium humates, was tested on maize (Zea mays) seedlings. In these tests, potassium humates achieved far better overall results than ammonium humates. Results were inter-correlated in order to appraise the influence of humic acids physical and chemical properties on biological activity. Surprisingly, fractions with the lowest molecular size (0-35 kDa) showed no correlation with bioactivity results (Pearson coefficient from 0.05 to -0.4). On the contrary, middle-sized fractions (35-175 kDa) showed highly significant positive correlation (Pearson coefficient up to 0.92) and the highest molecular-size-fractions (275-350 kDa) showed negative correlation (Pearson coefficient up to -0.75). These findings were identical for both potassium and ammonium humates. No connection was found between bioactivity of humates and polyols content which was remarkably high; it reached 150 mg per g of humic acids in the most extreme case of 5% hydrogene peroxide pre-treatment. In the final analysis, the preparation mode bore pivotal responsibility for the control of humic acids biological effect and showed the best results for potassium humates obtained from lignite pre-treated by acetic acid and by 2% hydrogen peroxide.

  7. In vitro dissolution study of acetylsalicylic acid solid dispersions. Tunable drug release allowed by the choice of polymer matrix

    Czech Academy of Sciences Publication Activity Database

    Policianová, Olivia; Brus, Jiří; Hrubý, Martin; Urbanová, Martina

    2015-01-01

    Roč. 20, č. 8 (2015), s. 935-940 ISSN 1083-7450 R&D Projects: GA ČR(CZ) GA14-03636S; GA ČR GPP106/11/P426 Grant - others:AV ČR(CZ) M200501201 Program:M Institutional support: RVO:61389013 Keywords : acetylsallicylic acid * controlled drug release * polymers Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.566, year: 2015

  8. Nonlinear optical studies on 4-(ferrocenylmethylimino)-2-hydroxy-benzoic acid thin films deposited by matrix-assisted pulsed laser evaporation (MAPLE)

    Energy Technology Data Exchange (ETDEWEB)

    Matei, Andreea [INFLPR - National Institute for Laser, Plasma and Radiation Physics, 409 Atomistilor Str., Magurele RO-077125, Bucharest (Romania); Marinescu, Maria, E-mail: maria.marinescu@chimie.unibuc.ro [UB - University of Bucharest, Faculty of Chemistry, 90-92 Şoseaua Panduri, Sector 5, RO-010184, Bucharest (Romania); Constantinescu, Catalin, E-mail: catalin.constantinescu@inflpr.ro [INFLPR - National Institute for Laser, Plasma and Radiation Physics, 409 Atomistilor Str., Magurele RO-077125, Bucharest (Romania); Ion, Valentin; Mitu, Bogdana [INFLPR - National Institute for Laser, Plasma and Radiation Physics, 409 Atomistilor Str., Magurele RO-077125, Bucharest (Romania); Ionita, Iulian [INFLPR - National Institute for Laser, Plasma and Radiation Physics, 409 Atomistilor Str., Magurele RO-077125, Bucharest (Romania); UB - University of Bucharest, Faculty of Physics, 405 Atomistilor Str., Magurele RO-077125, Bucharest (Romania); Dinescu, Maria [INFLPR - National Institute for Laser, Plasma and Radiation Physics, 409 Atomistilor Str., Magurele RO-077125, Bucharest (Romania); Emandi, Ana [INFLPR - National Institute for Laser, Plasma and Radiation Physics, 409 Atomistilor Str., Magurele RO-077125, Bucharest (Romania); UB - University of Bucharest, Faculty of Chemistry, 90-92 Şoseaua Panduri, Sector 5, RO-010184, Bucharest (Romania)

    2016-06-30

    Graphical abstract: - Highlights: • A newly synthesized ferrocene-derivative exhibits SHG potential. • Matrix-assisted pulsed laser evaporation is employed for thin film fabrication. • The optical properties of the films are investigated, presented and discussed. • At maximum laser output power, the SHG signal is strongly influenced by thin film thickness. - Abstract: We present results on a new, laboratory synthesized ferrocene-derivative, i.e. 4-(ferrocenylmethylimino)-2-hydroxy-benzoic acid. Thin films with controlled thickness are deposited by matrix-assisted pulsed laser evaporation (MAPLE), on quartz and silicon substrates, with the aim of evaluating the nonlinear optical properties for potential optoelectronic applications. Dimethyl sulfoxide was used as matrix, with 1% wt. concentration of the guest compound. The frozen target is irradiated by using a Nd:YAG laser (4ω/266 nm, 7 ns pulse duration, 10 Hz repetition rate), at low fluences ranging from 0.1 to 1 J/cm{sup 2}. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) are used to probe the surface morphology of the films. Fourier transform infrared (FTIR) and Raman spectroscopy reveal similar structure of the thin film material when compared to the starting material. The optical properties of the thin films are investigated by spectroscopic-ellipsometry (SE), and the refractive index dependence with respect to temperature is studied. The second harmonic generation (SHG) potential is assessed by using a femtosecond Ti:sapphire laser (800 nm, 60–100 fs pulse duration, 80 MHz repetition rate), at 200 mW maximum output power, revealing that the SHG signal intensity is strongly influenced by the films’ thickness.

  9. Gallic acid abolishes the EGFR/Src/Akt/Erk-mediated expression of matrix metalloproteinase-9 in MCF-7 breast cancer cells.

    Science.gov (United States)

    Chen, Ying-Jung; Lin, Ku-Nan; Jhang, Li-Mei; Huang, Chia-Hui; Lee, Yuan-Chin; Chang, Long-Sen

    2016-05-25

    Several studies have revealed that natural compounds are valuable resources to develop novel agents against dysregulation of the EGF/EGFR-mediated matrix metalloproteinase-9 (MMP-9) expression in cancer cells. In view of the findings that EGF/EGFR-mediated MMP-9 expression is closely related to invasion and metastasis of breast cancer. To determine the beneficial effects of gallic acid on the suppression of breast cancer metastasis, we explored the effect of gallic acid on MMP-9 expression in EGF-treated MCF-7 breast cancer cells. Treatment with EGF up-regulated MMP-9 mRNA and protein levels in MCF-7 cells. EGF treatment induced phosphorylation of EGFR and elicited Src activation, subsequently promoting Akt/NFκB (p65) and ERK/c-Jun phosphorylation in MCF-7 cells. Activation of Akt/p65 and ERK/c-Jun was responsible for the MMP-9 up-regulation in EGF-treated cells. Gallic acid repressed the EGF-induced activation of EGFR and Src; furthermore, inactivation of Akt/p65 and ERK/c-Jun was a result of the inhibitory effect of gallic acid on the EGF-induced MMP-9 up-regulation. Over-expression of constitutively active Akt and MEK1 or over-expression of constitutively active Src eradicated the inhibitory effect of gallic acid on the EGF-induced MMP-9 up-regulation. A chromosome conformation capture assay showed that EGF induced a chromosomal loop formation in the MMP-9 promoter via NFκB/p65 and AP-1/c-Jun activation. Treatment with gallic acid, EGFR inhibitor, or Src inhibitor reduced DNA looping. Taken together, our data suggest that gallic acid inhibits the activation of EGFR/Src-mediated Akt and ERK, leading to reduced levels of p65/c-Jun-mediated DNA looping and thus inhibiting MMP-9 expression in EGF-treated MCF-7 cells. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  10. Stimulation of Interleukin-10 Production by Acidic β-Lactoglobulin-Derived Peptides Hydrolyzed with Lactobacillus paracasei NCC2461 Peptidases

    OpenAIRE

    Prioult, Guénolée; Pecquet, Sophie; Fliss, Ismail

    2004-01-01

    We have previously demonstrated that Lactobacillus paracasei NCC2461 may help to prevent cow's milk allergy in mice by inducing oral tolerance to β-lactoglobulin (BLG). To investigate the mechanisms involved in this beneficial effect, we examined the possibility that L. paracasei induces tolerance by hydrolyzing BLG-derived peptides and liberating peptides that stimulate interleukin-10 (IL-10) production. L. paracasei peptidases have been shown to hydrolyze tryptic-chymotryptic peptides from ...

  11. Mixed-matrix membranes with enhanced antifouling activity: probing the surface-tailoring potential of Tiron and chromotropic acid for nano-TiO2.

    Science.gov (United States)

    Pal, Avishek; Dey, T K; Debnath, A K; Bhushan, Bharat; Sahu, A K; Bindal, R C; Kar, Soumitra

    2017-09-01

    Mixed-matrix membranes (MMMs) were developed by impregnating organofunctionalized nanoadditives within fouling-susceptible polysulfone matrix following the non-solvent induced phase separation (NIPS) method. The facile functionalization of nanoparticles of anatase TiO 2 (nano-TiO 2 ) by using two different organoligands, viz . Tiron and chromotropic acid, was carried out to obtain organofunctionalized nanoadditives, F T -nano-TiO 2 and F C -nano-TiO 2 , respectively. The structural features of nanoadditives were evaluated by X-ray diffraction, X-ray photoelectron spectroscopy, Raman and Fourier transform infrared spectroscopy, which established that Tiron leads to the blending of chelating and bridging bidentate geometries for F T -nano-TiO 2 , whereas chromotropic acid produces bridging bidentate as well as monodentate geometries for F C -nano-TiO 2 . The surface chemistry of the studied membranes, polysulfone (Psf): F T -nano-TiO 2 UF and Psf: F C -nano-TiO 2 UF, was profoundly influenced by the benign distributions of the nanoadditives enriched with distinctly charged sites ([Formula: see text]), as evidenced by superior morphology, improved topography, enhanced surface hydrophilicity and altered electrokinetic features. The membranes exhibited enhanced solvent throughputs, viz . 3500-4000 and 3400-4300 LMD at 1 bar of transmembrane pressure, without significant compromise in their rejection attributes. The flux recovery ratios and fouling resistive behaviours of MMMs towards bovine serum albumin indicated that the nanoadditives could impart stable and appreciable antifouling activity, potentially aiding in a sustainable ultrafiltration performance.

  12. Mechanical stimulation induces mTOR signaling via an ERK-independent mechanism: implications for a direct activation of mTOR by phosphatidic acid.

    Directory of Open Access Journals (Sweden)

    Jae Sung You

    Full Text Available Signaling by mTOR is a well-recognized component of the pathway through which mechanical signals regulate protein synthesis and muscle mass. However, the mechanisms involved in the mechanical regulation of mTOR signaling have not been defined. Nevertheless, recent studies suggest that a mechanically-induced increase in phosphatidic acid (PA may be involved. There is also evidence which suggests that mechanical stimuli, and PA, utilize ERK to induce mTOR signaling. Hence, we reasoned that a mechanically-induced increase in PA might promote mTOR signaling via an ERK-dependent mechanism. To test this, we subjected mouse skeletal muscles to mechanical stimulation in the presence or absence of a MEK/ERK inhibitor, and then measured several commonly used markers of mTOR signaling. Transgenic mice expressing a rapamycin-resistant mutant of mTOR were also used to confirm the validity of these markers. The results demonstrated that mechanically-induced increases in p70(s6k T389 and 4E-BP1 S64 phosphorylation, and unexpectedly, a loss in total 4E-BP1, were fully mTOR-dependent signaling events. Furthermore, we determined that mechanical stimulation induced these mTOR-dependent events, and protein synthesis, through an ERK-independent mechanism. Similar to mechanical stimulation, exogenous PA also induced mTOR-dependent signaling via an ERK-independent mechanism. Moreover, PA was able to directly activate mTOR signaling in vitro. Combined, these results demonstrate that mechanical stimulation induces mTOR signaling, and protein synthesis, via an ERK-independent mechanism that potentially involves a direct interaction of PA with mTOR. Furthermore, it appears that a decrease in total 4E-BP1 may be part of the mTOR-dependent mechanism through which mechanical stimuli activate protein synthesis.

  13. Novel chenodeoxycholic acid-sodium alginate matrix in the microencapsulation of the potential antidiabetic drug, probucol. An in vitro study.

    Science.gov (United States)

    Mooranian, Armin; Negrulj, Rebecca; Mikov, Momir; Golocorbin-Kon, Svetlana; Arfuso, Frank; Al-Salami, Hani

    2015-01-01

    We previously designed, developed and characterized a novel microencapsulated formulation as a platform for the targeted delivery of Probucol (PB) in an animal model of Type 2 Diabetes. The objective of this study is to optimize this platform by incorporating Chenodeoxycholic acid (CDCA), a bile acid with good permeation-enhancing properties, and examine its effect in vitro. Using sodium alginate (SA), we prepared PB-SA (control) and PB-CDCA-SA (test) microcapsules. CDCA resulted in better structural and surface characteristics, uniform morphology, and stable chemical and thermal profiles, while size and rheological parameters remained unchanged. PB-CDCA-SA microcapsules showed good excipients' compatibilities, as evidenced by differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy, scanning electron microscopy and energy dispersive X-ray spectroscopy studies. CDCA reduced microcapsule swelling at pH 7.8 at both 37 °C and 25 °C and improved PB-release. CDCA improved the characteristics and release properties of PB-microcapsules and may have potential in the targeted oral delivery of PB.

  14. Application of a simple column-switching ion chromatography technique for removal of matrix interferences and sensitive fluorescence determination of acidic compounds (pharmaceutical drugs) in complex samples.

    Science.gov (United States)

    Muhammad, Nadeem; Subhani, Qamar; Wang, Fenglian; Guo, Dandan; Zhao, Qiming; Wu, Shuchao; Zhu, Yan

    2017-09-15

    This work illustrates the introduction of a simple, rugged and flexible column-switching ion chromatography (IC) technique for an automated on-line QuEChERS extracted samples extracts washing followed by sensitive fluorescence (FLD) determination of five acidic pharmaceutical drugs namely; clofibric acid (CLO), ibuprofen (IBU), aspirin (ASP), naproxen (NAP) and flurobrofen (FLU) in three complex samples (spinach, apple and hospital sewage sludge). An old anion exchange column IonPac ® AS11-HC was utilized as a pre-treatment column for on-line washing of inorganic and organic interferences followed by isocratic separation of five acidic drugs with another anion exchange IonPac ® AS12A analytical column by exploiting the column-switching technique. This novel method exhibited good linearity with correlation coefficients (r 2 ) for all drugs were in the range 0.976-0.996. The limit of detection and quantification of all five acidic drugs were in the range 0.024μg/kg to 8.70μg/kg and 0.082μg/kg to 0.029mg/kg, respectively, and better recoveries in the range 81.17-112.5% with percentage relative standard deviations (RSDs) less than 17.8% were obtained. This on-line sample pre-treatment method showed minimum matrix effect in the range of 0.87-1.25 except for aspirin. This simple rugged and flexible column-switching system required only 28min for maximum elimination of matrices and interferences in three complex samples extracts, isocratic separation of five acidic drugs and for the continuous regeneration of pre-treatment column prior to every subsequent analysis. Finally, this simple automated IC system was appeared so rugged and flexible, which can eliminate and wash out most of interference, impurities and matrices in complex samples, simply by adjusting the NaOH and acetonitrile concentration in washing mobile phase with maximum recoveries of acidic analytes of interest. Copyright © 2017. Published by Elsevier B.V.

  15. Frost decreases content of sugars, ascorbic acid and some quercetin glycosides but stimulates selected carotenes in Rosa canina hips.

    Science.gov (United States)

    Cunja, Vlasta; Mikulic-Petkovsek, Maja; Zupan, Anka; Stampar, Franci; Schmitzer, Valentina

    2015-04-15

    Primary and secondary metabolites of Rosa canina hips were determined by HPLC/MS during ripening and after frost damage. Rose hips were harvested six times from the beginning of September until the beginning of December. Color parameters a*, b* and L* decreased during maturation. Glucose and fructose were the predominant sugars representing up to 92% total sugars, and citric acid was the major organic acid detected in rose hips (constituting up to 58% total organic acids). Total sugar and ascorbic acid content significantly decreased after frost damage; from 42.2 to 25.9 g 100 g(-1) DW for sugars and from 716.8 to 176.0 mg 100 g(-1) DW for ascorbic acid. Conversely, β-carotene and lycopene levels increased in frostbitten rose hips to 22.1 and 113.2 mg 100 g(-1) DW, respectively. In addition to cyanidin-3-glucoside (highest level in hips was 125.7 μg 100 g (-1) DW), 45 different phenolic compounds have been identified. The most abundant were proanthocyanidins (their levels amounted up to 90% of total flavanol content) and their content showed no significant differences during maturation. The levels of catechin, phloridzin, flavanones and several quercetin glycosides were highest on the first three sampling dates and decreased after frost. Antioxidant capacity similarly decreased in frostbitten rose hips. Total phenolic content increased until the third sampling and decreased on later samplings. Copyright © 2015 Elsevier GmbH. All rights reserved.

  16. Mechanical performance evaluation of bionanocomposites with polymeric matrix of poly(lactic acid)-PLA and organo clay

    International Nuclear Information System (INIS)

    Cavalcanti, Shirley N.; Melo, Tomas J.A. de; Araujo, Edcleide M.; Oliveira, Akidauana D.A.; Lima, Jessica C.C.

    2011-01-01

    The aim of this study is to evaluate the influence of ethylene/methyl acrylate (EMA) and ethylene/glycidyl methacrylate (E-GMA) copolymers and organoclay on the mechanical properties of polymer PLA-poly (lactic acid), from the system PLA / organoclay. The clay was organophilized with the ionic surfactant praepagem and the mixtures were prepared in a modular twin screw extruder. The behavior of bionanocomposites was evaluated by tensile and impact tests. The results of FTIR and DR-X indicated that the process was efficient organophilization. The mechanical properties showed that the elastic modulus and tensile strength of bionanocomposites obtained decreased compared to PLA. On the other hand there was a gain for resistance to impact, for all systems except for system PLA/OMMT. (author)

  17. Extended hormone binding site of the human thyroid stimulating hormone receptor: distinctive acidic residues in the hinge region are involved in bovine thyroid stimulating hormone binding and receptor activation.

    Science.gov (United States)

    Mueller, Sandra; Kleinau, Gunnar; Jaeschke, Holger; Paschke, Ralf; Krause, Gerd

    2008-06-27

    The human thyroid stimulating hormone receptor (hTSHR) belongs to the glycoprotein hormone receptors that bind the hormones at their large extracellular domain. The extracellular hinge region of the TSHR connects the N-terminal leucine-rich repeat domain with the membrane-spanning serpentine domain. From previous studies we reasoned that apart from hormone binding at the leucine-rich repeat domain, additional multiple hormone contacts might exist at the hinge region of the TSHR by complementary charge-charge recognition. Here we investigated highly conserved charged residues in the hinge region of the TSHR by site-directed mutagenesis to identify amino acids interacting with bovine TSH (bTSH). Indeed, the residues Glu-297, Glu-303, and Asp-382 in the TSHR hinge region are essential for bTSH binding and partially for signal transduction. Side chain substitutions showed that the negative charge of Glu-297 and Asp-382 is necessary for recognition of bTSH by the hTSHR. Multiple combinations of alanine mutants of the identified positions revealed an increased negative effect on hormone binding. An assembled model suggests that the deciphered acidic residues form negatively charged patches at the hinge region resulting in an extended binding mode for bTSH on the hTSHR. Our data indicate that certain positively charged residues of bTSH might be involved in interaction with the identified negatively charged amino acids of the hTSHR hinge region. We demonstrate that the hinge region represents an extracellular intermediate connector for both hormone binding and signal transduction of the hTSHR.

  18. Hyaluronic acid fillers with cohesive polydensified matrix for soft-tissue augmentation and rejuvenation: a literature review

    Science.gov (United States)

    Prasetyo, Adri D; Prager, Welf; Rubin, Mark G; Moretti, Ernesto A; Nikolis, Andreas

    2016-01-01

    Background Cohesive monophasic polydensified fillers show unique viscoelastic properties and variable density of hyaluronic acid, allowing for a homogeneous tissue integration and distribution of the material. Objective The aim of this paper was to review the clinical data regarding the performance, tolerability, and safety of the Belotero® fillers for soft-tissue augmentation and rejuvenation. Methods A literature search was performed up until May 31, 2015 to identify all relevant articles on Belotero® fillers (Basic/Balance, Hydro, Soft, Intense, Volume) and equivalent products (Esthélis®, Mesolis®, Fortélis®, Modélis®). Results This comprehensive review included 26 papers. Findings from three randomized controlled trials showed a greater reduction in nasolabial fold severity with Belotero® Basic/Balance than with collagen (at 8, 12, 16, and 24 weeks, n=118) and Restylane® (at 4 weeks, n=40), and higher patient satisfaction with Belotero® Intense than with Perlane® (at 2 weeks, n=20). With Belotero® Basic/Balance, an improvement of at least 1 point on the severity scale can be expected in ~80% of patients 1–6 months after injection, with an effect still visible at 8–12 months. Positive findings were also reported with Belotero® Volume (no reduction in hyaluronic acid volume at 12 months, as demonstrated by magnetic resonance imaging), Soft (improvement in the esthetic outcomes when used in a sequential approach), and Hydro (improvement in skin appearance in all patients). The most common adverse effects were mild-to-moderate erythema, edema, and hematoma, most of which were temporary. There were no reports of Tyndall effect, nodules, granulomas, or tissue necrosis. Conclusion Clinical evidence indicates sustainable esthetic effects, good safety profile, and long-term tolerability of the Belotero® fillers, particularly Belotero® Basic/Balance and Intense. PMID:27660479

  19. IL-33 stimulates expression of the GPR84 (EX33) fatty acid receptor gene and of cytokine and chemokine genes in human adipocytes.

    Science.gov (United States)

    Zaibi, Mohamed S; Kępczyńska, Małgorzata A; Harikumar, Parvathy; Alomar, Suliman Y; Trayhurn, Paul

    2018-05-15

    Expression of GPCR fatty acid sensor/receptor genes in adipocytes is modulated by inflammatory mediators, particularly IL-1β. In this study we examined whether the IL-1 gene superfamily member, IL-33, also regulates expression of the fatty acid receptor genes in adipocytes. Human fat cells, differentiated from preadipocytes, were incubated with IL-33 at three different dose levels for 3 or 24 h and mRNA measured by qPCR. Treatment with IL-33 induced a dose-dependent increase in GPR84 mRNA at 3 h, the level with the highest dose being 13.7-fold greater than in controls. Stimulation of GPR84 expression was transitory; the mRNA level was not elevated at 24 h. In contrast to GPR84, IL-33 had no effect on GPR120 expression. IL-33 markedly stimulated expression of the IL1B, CCL2, IL6, CXCL2 and CSF3 genes, but there was no effect on ADIPOQ expression. The largest effect was on CSF3, the mRNA level of which increased 183-fold over controls at 3 h with the highest dose of IL-33; there was a parallel increase in the secretion of G-CSF protein into the medium. It is concluded that in human adipocytes IL-33, which is synthesised in adipose tissue, has a strong stimulatory effect on the expression of cytokine and chemokine genes, particularly CSF3, and on the expression of GPR84, a pro-inflammatory fatty acid receptor. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Immunocytochemical localization of glutamic acid decarboxylase (GAD) and substance P in neural areas mediating motion-induced emesis: Effects of vagal stimulation on GAD immunoreactivity

    Science.gov (United States)

    Damelio, F.; Gibbs, M. A.; Mehler, W. R.; Daunton, Nancy G.; Fox, Robert A.

    1991-01-01

    Immunocytochemical methods were employed to localize the neurotransmitter amino acid gamma-aminobutyric acid (GABA) by means of its biosynthetic enzyme glutamic acid decarboxylase (GAD) and the neuropeptide substance P in the area postrema (AP), area subpostrema (ASP), nucleus of the tractus solitarius (NTS), and gelatinous nucleus (GEL). In addition, electrical stimulation was applied to the night vagus nerve at the cervical level to assess the effects on GAD-immunoreactivity (GAR-IR). GAD-IR terminals and fibers were observed in the AP, ASP, NTS, and GEL. They showed pronounced density at the level of the ASP and gradual decrease towards the solitary complex. Nerve cells were not labelled in our preparations. Ultrastructural studies showed symmetric or asymmetric synaptic contracts between labelled terminals and non-immunoreactive dendrites, axons, or neurons. Some of the labelled terminals contained both clear- and dense-core vesicles. Our preliminary findings, after electrical stimulation of the vagus nerve, revealed a bilateral decrease of GAD-IR that was particularly evident at the level of the ASP. SP-immunoreactive (SP-IR) terminals and fibers showed varying densities in the AP, ASP, NTS, and GEL. In our preparations, the lateral sub-division of the NTS showed the greatest accumulation. The ASP showed medium density of immunoreactive varicosities and terminals and the AP and GEL displayed scattered varicose axon terminals. The electron microscopy revealed that all immunoreactive terminals contained clear-core vesicles which make symmetric or asymmetric synaptic contact with unlabelled dendrites. It is suggested that the GABAergic terminals might correspond to vagal afferent projections and that GAD/GABA and substance P might be co-localized in the same terminal allowing the possibility of a regulated release of the transmitters in relation to demands.

  1. High Leucine Diets Stimulate Cerebral Branched-Chain Amino Acid Degradation and Modify Serotonin and Ketone Body Concentrations in a Pig Model.

    Directory of Open Access Journals (Sweden)

    Anna G Wessels

    Full Text Available In addition to its role as an essential protein component, leucine (Leu displays several other metabolic functions such as activation of protein synthesis. This property makes it an interesting amino acid for the therapy of human muscle atrophy and for livestock production. However, Leu can stimulate its own degradation via the branched-chain keto acid dehydrogenase complex (BCKDH. To examine the response of several tissues to excessive Leu, pigs were fed diets containing two- (L2 and four-fold (L4 higher Leu contents than the recommended amount (control. We found that the L4 diet led to a pronounced increase in BCKDH activity in the brain (2.5-fold, P < 0.05, liver (1.8-fold, P < 0.05 and cardiac muscle (1.7-fold, P < 0.05, whereas we found no changes in enzyme activity in the pancreas, skeletal muscle, adipose tissue and intestinal mucosa. The L2 diet had only weak effects on BCKDH activity. Both high Leu diets reduced the concentrations of free valine and isoleucine in nearly all tissues. In the brain, high Leu diets modified the amount of tryptophan available: for serotonin synthesis. Compared to the controls, pigs treated with the high Leu diets consumed less food, showed increased plasma concentrations of 3-hydroxybutyrate and reduced levels of circulating serotonin. In conclusion, excessive Leu can stimulate BCKDH activity in several tissues, including the brain. Changes in cerebral tryptophan, along with the changes in amino acid-derived metabolites in the plasma may limit the use of high Leu diets to treat muscle atrophy or to increase muscle growth.

  2. The Extraction and Determination of Ellagic Acid Content in the Peels of Six Iranian Pomegranates Cultivars Using a New Miniaturized Matrix Solid-Phase Dispersion Method

    Directory of Open Access Journals (Sweden)

    Fariba Nazari Serenjeh

    2017-03-01

    Full Text Available Background and Aim:The peels of six Iranian pomegranates (Punica granatum L. cultivars, as a traditional medicine, were treated with a new miniaturized matrix solid-phase dispersion (MSPD method for the HPLC determination of ellagic acid (EA. Materials and Methods:In the proposed method, only 10mg of the sample powder was ground and blended with an equal amount of C18 sorbent in an agate mortar. The use of the agate mortar with smooth surface facilitated the sample transfer into a cartridge and reduced the required amount of sample and sorbent. Micro volumes of dichloromethane, n-hexane and methanol were used as modifier, washing and elution solvents, respectively. The eluate was injected into an HPLC-UV system for the analysis. Results:Several factors such as the type and amount of dispersing sorbent, modifier, washing solvent and eluent were carefully studied and optimized. Six replicated analyses at the optimized conditions resulted in a recovery of 96.7% and a relative standard deviation of 5.87%. The proposed method was successfully applied to the extraction and determination of EA in the peels samples. Conclusion:According to the ultimate results, the MSPD method is an efficient technique for the quantitative extraction of EA from the peels of pomegranate. Malas cultivar has the highest amount (18.1 g kg-1 of ellagic acid content compared to the other studied pomegranate cultivars.

  3. Stimulation of reductive dechlorination of tetrachloroethane in anaerobic aquifer microcosms by addition of short-chain organic acids or alcohols

    International Nuclear Information System (INIS)

    Gibson, S.A.; Sewell, G.W.

    1992-01-01

    Although the ecological and public health risk associated with tetrachloroethene (PCE) contamination may be the most severe when spills affect groundwater, little is known about the environmental conditions necessary to initiate and sustain dehalogenation activity in contaminated aquifers. This study was done with core material collected from a site impacted by both aviation gasoline and chloroethenes at a Coast Guard Air Station at Traverse City, Michigan. The effect of the addition of common fermentation products on the dehalogenation of tetrachloroethene was studied in methanogenic slurries made with aquifer solids. Lactate, propionate, crotonate, butyrate, and ethanol stimulated dehalogenation activity, while acetate, methanol, and isopropanol did not

  4. Antioxidative activity of 3,4-dihydroxyplienylacetic acid and α-tocopherol on the triglyceride matrix of olive oil. Effect of acidity.

    Directory of Open Access Journals (Sweden)

    Blekas, Georgios

    1998-02-01

    Full Text Available Minor constituents of virgin olive oil are important for the remarkable stability of the oil in autoxidation, but the exact role and the extent to which each antioxidant factor contributes to the total antioxidant effect has not been thoroughly Investigated. In this study the role of α-tocopherol is explored at various acidity levels and at low concentrations of ortho-diphenols. A substrate of olive oil triacylglycerols devoid of prooxidant or antioxidant constituents was prepared from refined olive oil by column chromatography To tills substrate, slightly oxidized, the additives (oleic acid, 3,4-dihydroxyphenylacetic acid and α-tocopherol were added and the stability was assessed by periodical measurements of peroxide values. It was found that free fatty adds reduce mainly the protective activity of the ortho-diphenol. It is also concluded that α-tocopherol has a synergistic effect with the ortho-diphenols and contributes significantly to the retardation of peroxide formation. This is Important for oils poor in ortho-diphenols.

    Los constituyentes menores del aceite de oliva virgen son importantes para la notable estabilidad del aceite en la autooxidación, pero el papel exacto y el alcance con que cada factor antioxidante contribuye al efecto antioxidante total no ha sido investigado a fondo. En este estudio el papel del α-tocoferol es examinado a varios niveles de acidez y a baja concentraciones de o-difenoles. Un sustrato de triacilgliceroles de aceite de oliva desprovisto de constituyentes prooxidantes o antioxidantes fue preparado a partir de aceite de oliva refinado mediante cromatografía en columna. A este sustrato, un poco oxidado, los aditivos (ácido oleico, ácido 3,4-dihidroxifenilacético y α-tocoferol fueron añadidos y la estabilidad fue calculada mediante medidas periódicas del índice de peróxido. Se encontró que los ácidos grasos libres reducen principalmente la actividad protectora de los orto-difenoles. Se

  5. Dihydrotestosterone stimulates amino acid uptake and the expression of LAT2 in mouse skeletal muscle fibres through an ERK1/2-dependent mechanism

    Science.gov (United States)

    Hamdi, M M; Mutungi, G

    2011-01-01

    Abstract Dihydrotestosterone (DHT) has acute/non-genomic actions in adult mammalian skeletal muscles whose physiological functions are still poorly understood. Therefore, the primary aim of this study was to investigate the acute/non-genomic effects of DHT on amino acid uptake as well as the cellular signal transduction events underlying these actions in mouse fast- and slow-twitch skeletal muscle fibre bundles. 14C-Labelled amino acids were used to investigate the effects of DHT and testosterone (T) on amino acid uptake and pharmacological interventions were used to determine the cellular signal transduction events mediating these actions. While T had no effect on the uptake of isoleucine (Ile) and α-methylaminoisobutyric acid (MeAIB) in both fibre types, DHT increased their uptake in the fast-twitch fibre bundles. This effect was reversed by inhibitors of protein translation, the epidermal growth factor receptor (EGFR), system A, system L, mTOR and MEK. However, it was relatively insensitive to inhibitors of transcription, androgen receptors and PI3K/Akt. Additionally, DHT treatment increased the expression of LAT2 and the phosphorylation of the EGFR in the fast-twitch fibre bundles and that of ERK1/2, RSK1/2 and ATF2 in both fibre types. Also, it decreased the phosphorylation of eEF2 and increased the incorporation of Ile into proteins in both fibre types. Most of these effects were reversed by EGFR and MEK inhibitors. From these findings we suggest that another physiological function of the acute/non-genomic actions of DHT in isolated mammalian skeletal muscle fibres is to stimulate amino acid uptake. This effect is mediated through the EGFR and involves the activation of the MAPK pathway and an increase in LAT2 expression. PMID:21606113

  6. Effect of dopamine on pentagastrin-stimulated gastric acid secretion and mucosal blood flow in dogs with gastric fistula

    DEFF Research Database (Denmark)

    Hovendal, C P; Bech, K; Gottrup, F

    1982-01-01

    with selective blockade of alpha-, beta-, and dopaminergic receptors. A significant inhibition of gastric acid secretion was found with the highest dose of dopamine used (40 micrograms/kg/min). The kinetic study showed characteristics of a non-competitive type. The anti-secretory effect dopamine...

  7. Matrix theory

    CERN Document Server

    Franklin, Joel N

    2003-01-01

    Mathematically rigorous introduction covers vector and matrix norms, the condition-number of a matrix, positive and irreducible matrices, much more. Only elementary algebra and calculus required. Includes problem-solving exercises. 1968 edition.

  8. Hyaluronic acid fillers with cohesive polydensified matrix for soft-tissue augmentation and rejuvenation: a literature review

    Directory of Open Access Journals (Sweden)

    Prasetyo AD

    2016-09-01

    Full Text Available Adri D Prasetyo,1 Welf Prager,2 Mark G Rubin,3 Ernesto A Moretti,4 Andreas Nikolis5 1Rejuva Skin & Beauty, Surabaya, Indonesia; 2Prager & Partner, Hamburg, Germany; 3University of California, San Diego, CA, USA; 4Gamma Health Group, Sanatorio Los Arroyos, Santa Fe, Republic of Argentina; 5Victoria Park Clinical Research Centre, Westmount, QC, Canada Background: Cohesive monophasic polydensified fillers show unique viscoelastic properties and variable density of hyaluronic acid, allowing for a homogeneous tissue integration and distribution of the material.Objective: The aim of this paper was to review the clinical data regarding the performance, tolerability, and safety of the Belotero® fillers for soft-tissue augmentation and rejuvenation.Methods: A literature search was performed up until May 31, 2015 to identify all relevant articles on Belotero® fillers (Basic/Balance, Hydro, Soft, Intense, Volume and equivalent products (Esthélis®, Mesolis®, Fortélis®, Modélis®.Results: This comprehensive review included 26 papers. Findings from three randomized controlled trials showed a greater reduction in nasolabial fold severity with Belotero® Basic/Balance than with collagen (at 8, 12, 16, and 24 weeks, n=118 and Restylane® (at 4 weeks, n=40, and higher patient satisfaction with Belotero® Intense than with Perlane® (at 2 weeks, n=20. With Belotero® Basic/Balance, an improvement of at least 1 point on the severity scale can be expected in ~80% of patients 1–6 months after injection, with an effect still visible at 8–12 months. Positive findings were also reported with Belotero® Volume (no reduction in hyaluronic acid volume at 12 months, as demonstrated by magnetic resonance imaging, Soft (improvement in the esthetic outcomes when used in a sequential approach, and Hydro (improvement in skin appearance in all patients. The most common adverse effects were mild-to-moderate erythema, edema, and hematoma, most of which were

  9. Receptor for advanced glycation end products - membrane type1 matrix metalloproteinase axis regulates tissue factor expression via RhoA and Rac1 activation in high-mobility group box-1 stimulated endothelial cells.

    Directory of Open Access Journals (Sweden)

    Koichi Sugimoto

    Full Text Available BACKGROUND: Atherosclerosis is understood to be a blood vessel inflammation. High-mobility group box-1 (HMGB-1 plays a key role in the systemic inflammation. Tissue factor (TF is known to lead to inflammation which promotes thrombus formation. Membrane type1 matrix metalloprotease (MT1-MMP associates with advanced glycation endproducts (AGE triggered-TF protein expression and phosphorylation of NF-κB. However, it is still unclear about the correlation of MT1-MMP and HMBG-1-mediated TF expression. In this study, we investigated the molecular mechanisms of TF expression in response to HMGB-1 stimulation and the involvement of MT1-MMP in endothelial cells. METHODS AND RESULTS: Pull-down assays and Western blotting revealed that HMGB-1 induced RhoA/Rac1 activation and NF-kB phosphorylation in cultured human aortic endothelial cells. HMGB-1 increased the activity of MT1-MMP, and inhibition of RAGE or MT1-MMP by siRNA suppressed HMGB-1-induced TF upregulation as well as HMGB-1-triggered RhoA/Rac1 activation and NF-kB phosphorylation. CONCLUSIONS: The present study showed that RAGE/MT1-MMP axis modified HMBG-1-mediated TF expression through RhoA and Rac1 activation and NF-κB phosphorylation in endothelial cells. These results suggested that MT1-MMP was involved in vascular inflammation and might be a good target for treating atherosclerosis.

  10. The ECM-Cell Interaction of Cartilage Extracellular Matrix on Chondrocytes

    Directory of Open Access Journals (Sweden)

    Yue Gao

    2014-01-01

    Full Text Available Cartilage extracellular matrix (ECM is composed primarily of the network type II collagen (COLII and an interlocking mesh of fibrous proteins and proteoglycans (PGs, hyaluronic acid (HA, and chondroitin sulfate (CS. Articular cartilage ECM plays a crucial role in regulating chondrocyte metabolism and functions, such as organized cytoskeleton through integrin-mediated signaling via cell-matrix interaction. Cell signaling through integrins regulates several chondrocyte functions, including differentiation, metabolism, matrix remodeling, responses to mechanical stimulation, and cell survival. The major signaling pathways that regulate chondrogenesis have been identified as wnt signal, nitric oxide (NO signal, protein kinase C (PKC, and retinoic acid (RA signal. Integrins are a large family of molecules that are central regulators in multicellular biology. They orchestrate cell-cell and cell-matrix adhesive interactions from embryonic development to mature tissue function. In this review, we emphasize the signaling molecule effect and the biomechanics effect of cartilage ECM on chondrogenesis.

  11. Fibrin promotes proliferation and matrix production of intervertebral disc cells cultured in three-dimensional poly(lactic-co-glycolic acid) scaffold.

    Science.gov (United States)

    Sha'ban, Munirah; Yoon, Sun Jung; Ko, Youn Kyung; Ha, Hyun Jung; Kim, Soon Hee; So, Jung Won; Idrus, Ruszymah Bt Hj; Khang, Gilson

    2008-01-01

    Previously, we have proven that fibrin and poly(lactic-co-glycolic acid) (PLGA) scaffolds facilitate cell proliferation, matrix production and early chondrogenesis of rabbit articular chondrocytes in in vitro and in vivo experiments. In this study, we evaluated the potential of fibrin/PLGA scaffold for intervertebral disc (IVD) tissue engineering using annulus fibrosus (AF) and nucleus pulposus (NP) cells in relation to potential clinical application. PLGA scaffolds were soaked in cells-fibrin suspension and polymerized by dropping thrombin-sodium chloride (CaCl(2)) solution. A PLGA-cell complex without fibrin was used as control. Higher cellular proliferation activity was observed in fibrin/PLGA-seeded AF and NP cells at each time point of 3, 7, 14 and 7 days using the MTT assay. After 3 weeks in vitro incubation, fibrin/PLGA exhibited a firmer gross morphology than PLGA groups. A significant cartilaginous tissue formation was observed in fibrin/PLGA, as proven by the development of cells cluster of various sizes and three-dimensional (3D) cartilaginous histoarchitecture and the presence of proteoglycan-rich matrix and glycosaminoglycan (GAG). The sGAG production measured by 1,9-dimethylmethylene blue (DMMB) assay revealed greater sGAG production in fibrin/PLGA than PLGA group. Immunohistochemical analyses showed expressions of collagen type II, aggrecan core protein and collagen type I genes throughout in vitro culture in both fibrin/PLGA and PLGA. In conclusion, fibrin promotes cell proliferation, stable in vitro tissue morphology, superior cartilaginous tissue formation and sGAG production of AF and NP cells cultured in PLGA scaffold. The 3D porous PLGA scaffold-cell complexes using fibrin can provide a vehicle for delivery of cells to regenerate tissue-engineered IVD tissue.

  12. Ethyl group as matrix modifier and inducer of ordered domains in hybrid xerogels synthesised in acidic media using ethyltriethoxysilane (ETEOS) and tetraethoxysilane (TEOS) as precursors

    International Nuclear Information System (INIS)

    Rios, Xabier; Moriones, Paula; Echeverría, Jesús C.; Luquin, Asunción; Laguna, Mariano; Garrido, Julián J.

    2013-01-01

    Hybrid silica xerogels favourably combine the properties of organic and inorganic components in one material; consequently these materials are useful for multiple applications. The versatility and mild synthetic conditions provided by the sol-gel process are ideal for the synthesis of hybrid materials. The specific aims of this study were to synthesise hybrid xerogels in acidic media using tetraethoxysilane (TEOS) and ethyltriethoxysilane (ETEOS) as silica precursors, and to assess the role of the ethyl group as a matrix modifier and inducer of ordered domains in xerogels. All xerogels were synthesised at pH 4.5, at 60 °C, with 1:4.75:5.5 TEOS:EtOH:H 2 O molar ratio. Gelation time exponentially increased with the ETEOS molar ratio. Incorporation of the ethyl groups into the structure of xerogels reduced cross-linking, increased the average siloxane bond length, and promoted the formation of ordered domains. As a result, a transition from Q n to T n signals detected in the 29 Si NMR spectra, the Si–O structural band in the FTIR spectra shifted to lower wavelength, and a new peak in the XRD pattern at 2θ < 10° appeared in the XRD patterns. Mass spectroscopy detected fragments with high numbers of silicon atoms and a polymeric distribution. - Graphical abstract: Display Omitted - Highlights: • Hybrid xerogels were synthesised for ETEOS/TEOS mixtures up to 80% ETEOS. • The gelification time exponentially increased with ETEOS content. • FTIR, XRD and MAS NMR demonstrated the presence of ethyl groups into xerogels. • For ETEOS contents ≤30%, ethyl group acted as matrix modifier. • For ETEOS contents ≥30%, ethyl groups induced the formation of ordered domains

  13. Tissue inhibitor of matrix metalloproteinases-1 loaded poly(lactic-co-glycolic acid nanoparticles for delivery across the blood–brain barrier

    Directory of Open Access Journals (Sweden)

    Chaturvedi M

    2014-01-01

    Full Text Available Mayank Chaturvedi,1 Yves Molino,2 Bojja Sreedhar,3 Michel Khrestchatisky,4 Leszek Kaczmarek1 1Laboratory of Neurobiology, Nencki Institute, Warsaw, Poland; 2Vect-Horus, Marseille, France; 3Indian Institute of Chemical Technology, Hyderabad, India; 4Aix-Marseille Université, CNRS, NICN, UMR7259, Marseille, France Aim: The aim of this study was to develop poly(lactic-co-glycolic acid (PLGA nanoparticles (NPs for delivery of a protein – tissue inhibitor of matrix metalloproteinases 1 (TIMP-1 – across the blood–brain barrier (BBB to inhibit deleterious matrix metalloproteinases (MMPs. Materials and methods: The NPs were formulated by multiple-emulsion solvent-evaporation, and for enhancing BBB penetration, they were coated with polysorbate 80 (Ps80. We compared Ps80-coated and uncoated NPs for their toxicity, binding, and BBB penetration on primary rat brain capillary endothelial cell cultures and the rat brain endothelial 4 cell line. These studies were followed by in vivo studies for brain delivery of these NPs. Results: Results showed that neither Ps80-coated nor uncoated NPs caused significant opening of the BBB, and essentially they were nontoxic. NPs without Ps80 coating had more binding to endothelial cells compared to Ps80-coated NPs. Penetration studies showed that TIMP-1 NPs + Ps80 had 11.21%±1.35% penetration, whereas TIMP-1 alone and TIMP-1 NPs without Ps80 coating did not cross the endothelial monolayer. In vivo studies indicated BBB penetration of intravenously injected TIMP-1 NPs + Ps80. Conclusion: The study demonstrated that Ps80 coating of NPs does not cause significant toxic effects to endothelial cells and that it can be used to enhance the delivery of protein across endothelial cell barriers, both in vitro and in vivo. Keywords: PLGA nanoparticles, drug delivery, protein delivery, sustained release, brain delivery, BBB penetration, RBCEC culture

  14. Immunoprotective and leukopoiesis-stimulating effects of 10-hydroxy-Δ2-decenoic acid in patients under radiotherapy

    International Nuclear Information System (INIS)

    Xu Changshao; Yu Zhiying; Yao Deyuan

    1987-01-01

    10-Hydroxy-Δ 2 -decenoic acid(10-HDA) is an unique fatty acid component in royal jelly. It was used in randomized trials in 52 patients with malignant tumors. The synthesis of DNA in their T-lymphocytes induced by PHA was investigated by the determination of 3 H-TdR incorporation. Comparison of preirradiation 'cpm' values between 100 Gy dose groups showed no significant difference in degree of T-lymphocytes depression in the patients of treated groups. In the control group, however, 'cpm' values increased progressively with the increasing radiation dose. The results demonstrated that 10-HDA might have antiirradiation and immunoprotective effects during radiotherapy. It is concluded that 10-HDA is one of the safer and more effective adjuvant drugs in radiotherapy

  15. Improved solar light stimulated charge separation of g-C3N4 through self-altering acidic treatment

    Science.gov (United States)

    Leong, Kah Hon; Lim, Ping Feng; Sim, Lan Ching; Punia, Varun; Pichiah, Saravanan

    2018-02-01

    Herein, we report the use of acid treatment to treat g-C3N4 nanostructured by a direct and facile synthesis route. The adopted treatment enhanced photoactivity of g-C3N4 and reflected in the removal of recalcitrant organic pollutant, Bisphenol A under direct sunlight. A complete removal of Bisphenol A was attained in a short duration (225 min) as compared to pure g-C3N4. The analysis clearly substantiated the robustness of acid exfoliation that promoted a blue shift, extended the conjugated length of its respective conduction and valance band. It also drastically prolonged the recombination rate of charge carriers, by producing excess of unpaired electrons in the conduction band for active radicals' generation. Thus, this new findings could offer a new sight of self-alteration in improving the photoactivity of complex organic pollutants for sustainable environmental remediation.

  16. Delayed translocation of NGFI-B/RXR in glutamate stimulated neurons allows late protection by 9-cis retinoic acid

    International Nuclear Information System (INIS)

    Mathisen, Gro H.; Fallgren, Asa B.; Strom, Bjorn O.; Boldingh Debernard, Karen A.; Mohebi, Beata U.; Paulsen, Ragnhild E.

    2011-01-01

    Highlights: → NGFI-B and RXR translocate out of the nucleus after glutamate treatment. → Arresting NGFI-B/RXR in the nucleus protects neurons from excitotoxicity. → Late protection by 9-cis RA is possible due to a delayed translocation of NGFI-B/RXR. -- Abstract: Nuclear receptor and apoptosis inducer NGFI-B translocates out of the nucleus as a heterodimer with RXR in response to different apoptosis stimuli, and therefore represents a potential pharmacological target. We found that the cytosolic levels of NGFI-B and RXRα were increased in cultures of cerebellar granule neurons 2 h after treatment with glutamate (excitatory neurotransmitter in the brain, involved in stroke). To find a time-window for potential intervention the neurons were transfected with gfp-tagged expressor plasmids for NGFI-B and RXR. The default localization of NGFI-Bgfp and RXRgfp was nuclear, however, translocation out of the nucleus was observed 2-3 h after glutamate treatment. We therefore hypothesized that the time-window between treatment and translocation would allow late protection against neuronal death. The RXR ligand 9-cis retinoic acid was used to arrest NGFI-B and RXR in the nucleus. Addition of 9-cis retinoic acid 1 h after treatment with glutamate reduced the cytosolic translocation of NGFI-B and RXRα, the cytosolic translocation of NGFI-Bgfp observed in live neurons, as well as the neuronal death. However, the reduced translocation and the reduced cell death were not observed when 9-cis retinoic acid was added after 3 h. Thus, late protection from glutamate induced death by addition of 9-cis retinoic acid is possible in a time-window after apoptosis induction.

  17. Ascorbic acid treatment elevates follicle stimulating hormone and testosterone plasma levels and enhances sperm quality in albino Wistar rats

    OpenAIRE

    Okon, Uduak Akpan; Utuk, Ikponoabasi Ibanga

    2016-01-01

    Background: Infertility issues have been linked to the effect of oxidative reaction in the reproductive system. This study evaluated the effect of ascorbic acid, on fertility parameters of male albino Wistar rats was studied. Materials and Methods: Eighteen albino Wistar rats weighed between 178 g and 241 g were used, randomly assigned into three groups. Group 1 was the control group; oral gavaged 5 ml of distilled water; Groups 2 and 3 were administered medium dose (250 mg/kg) and high dose ...

  18. Synthesis of Copper-Chelates Derived from Amino Acids and Evaluation of Their Efficacy as Copper Source and Growth Stimulator for Lactuca sativa in Nutrient Solution Culture.

    Science.gov (United States)

    Kaewchangwat, Narongpol; Dueansawang, Sattawat; Tumcharern, Gamolwan; Suttisintong, Khomson

    2017-11-15

    Five tetradentate ligands were synthesized from l-amino acids and utilized for the synthesis of Cu(II)-chelates 1-5. The efficacy of Cu(II)-chelates as copper (Cu) source and growth stimulator in hydroponic cultivation was evaluated with Lactuca sativa. Their stability test was performed at pH 4-10. The results suggested that Cu(II)-chelate 3 is the most pH tolerant complex. Levels of Cu, Zn, and Fe accumulated in plants supplied with Cu(II)-chelates were compared with those supplied with CuSO 4 at the same Cu concentration of 8.0 μM. The results showed that Cu(II)-chelate 3 significantly enhanced Cu, Zn, and Fe content in shoot by 35, 15, and 48%, respectively. Application of Cu(II)-chelate 3 also improved plant dry matter yield by 54%. According to the results, Cu(II)-chelate 3 demonstrated the highest stimulating effect on plant growth and plant mineral accumulation so that it can be used as an alternative to CuSO 4 for supplying Cu in nutrient solutions and enhancing the plant growth.

  19. Effects of methyl gallate and gallic acid on the production of inflammatory mediators interleukin-6 and interleukin-8 by oral epithelial cells stimulated with Fusobacterium nucleatum.

    Science.gov (United States)

    Kang, Mi-Sun; Jang, Hee-Sook; Oh, Jong-Suk; Yang, Kyu-Ho; Choi, Nam-Ki; Lim, Hoi-Soon; Kim, Seon-Mi

    2009-12-01

    Interactions between periodontal bacteria and human oral epithelial cells can lead to the activation and expression of a variety of inflammatory mediators in epithelial cells. Fusobacterium nucleatum is a filamentous human pathogen that is strongly associated with periodontal diseases. This study examined the effects of methyl gallate (MG) and gallic acid (GA) on the production of inflammatory mediators, interleukin (IL)-6 and IL-8, by oral epithelial cells stimulated by F. nucleatum. In a real-time reverse transcription-polymerase chain reaction and an enzyme-linked immunosorbent assay, live F. nucleatum induced high levels of gene expression and protein release of IL-6 and IL-8. The effects of MG and GA were examined by treating KB oral epithelial cells with MG and GA and stimulating them with F. nucleatum. MG and GA inhibited significantly the increases in the IL-6 and IL-8 gene and protein levels in a dose-dependent manner. These Compounds also inhibited the growth of F. nucleatum. No visible effects of MG and GA on the adhesion and invasion of KB cells by F. nucleatum were observed. In conclusion, both MG and GA inhibit IL-6 and IL-8 production from F. nucleatum-activated KB cells.

  20. Plasma rich in growth factors (PRGF-Endoret) stimulates tendon and synovial fibroblasts migration and improves the biological properties of hyaluronic acid.

    Science.gov (United States)

    Anitua, E; Sanchez, M; De la Fuente, M; Zalduendo, M M; Orive, G

    2012-09-01

    Cell migration plays an essential role in development, wound healing, and tissue regeneration. Plasma rich in growth factors (PRGF-Endoret) technology offers a potential source of growth factors involved in tissue regeneration. Here, we evaluate the potential of PRGF-Endoret over tendon cells and synovial fibroblasts migration and study whether the combination of this autologous technology with hyaluronic acid (HA) improves the effect and potential of the biomaterials over the motility of both types of fibroblasts. Migration of primary tendon cells and synovial fibroblasts after culturing with either PRGF or PPGF (plasma poor in growth factors) at different doses was evaluated. Furthermore, the migratory capacity induced by the combination of PPGF and PRGF with HA was tested. PPGF stimulated migration of both types of cells but this effect was significantly higher when PRGF was used. Tendon cells showed an increase of 212% in migratory ability when HA was combined with PPGF and of 335% in the case of HA + PRGF treatment compared with HA alone. PRGF-Endoret stimulates migration of tendon cells and synovial fibroblasts and improves the biological properties of HA.

  1. Comparison of Buffer Effect of Different Acids During Sandstone Acidizing

    International Nuclear Information System (INIS)

    Shafiq, Mian Umer; Mahmud, Hisham Khaled Ben; Hamid, Mohamed Ali

    2015-01-01

    The most important concern of sandstone matrix acidizing is to increase the formation permeability by removing the silica particles. To accomplish this, the mud acid (HF: HCl) has been utilized successfully for many years to stimulate the sandstone formations, but still it has many complexities. This paper presents the results of laboratory investigations of different acid combinations (HF: HCl, HF: H 3 PO 4 and HF: HCOOH). Hydrofluoric acid and fluoboric acid are used to dissolve clays and feldspar. Phosphoric and formic acids are added as a buffer to maintain the pH of the solution; also it allows the maximum penetration of acid into the core sample. Different tests have been performed on the core samples before and after the acidizing to do the comparative study on the buffer effect of these acids. The analysis consists of permeability, porosity, color change and pH value tests. There is more increase in permeability and porosity while less change in pH when phosphoric and formic acids were used compared to mud acid. From these results it has been found that the buffer effect of phosphoric acid and formic acid is better than hydrochloric acid. (paper)

  2. Recycling of wastes from fish beneficiation by composting: chemical characteristics of the compost and efficiency of their humic acids in stimulating the growth of lettuce.

    Science.gov (United States)

    Busato, Jader Galba; de Carvalho, Caroline Moreira; Zandonadi, Daniel Basilio; Sodré, Fernando Fabriz; Mol, Alan Ribeiro; de Oliveira, Aline Lima; Navarro, Rodrigo Diana

    2017-11-23

    Waste from the beneficiation of fish was composted with crushed grass aiming to characterize their chemical composition and investigate the possibility of the use of the final compost as source of humic acids (HA) able to stimulate the growth of lettuce. Compost presented pH value, C/N ratio, and electrical conductivity that allow its use as an organic fertilizer. The element content was present in the following order of abundance in the compost: P > Ca > N > Mg > K > Fe > Zn > Mn > Mo > Cu, and the humus composition was similar to that observed in others kind of organic residues composted. The high content of oxygen pointed out a high level of oxidation of HA, in line with the predominance of phenolic acidity in the functional groups. The 13 C-NMR spectra showed marked resonances due to the presence of lipids and other materials resistant to degradation as methoxy substituent and N-alkyl groups. A concentration of 20 mg L -1 HA increased significantly both dry and wet root matter in lettuce but the CO 2 assimilation, stomatal conductance, and number of lateral roots of the plants were not affected. However, increases of 64% in the water-use efficiency was observed due to the HA addition, probably related to the root morphology alteration which resulted in 1.6-fold increase of lateral root average length and due to the higher H + extrusion activity. Reuse of residues from the fish beneficiation activity by composting may represent a safe tool to increase the value of recycled organic residues and generate HA with potential use as plant growth stimulants.

  3. A dark brown roast coffee blend is less effective at stimulating gastric acid secretion in healthy volunteers compared to a medium roast market blend.

    Science.gov (United States)

    Rubach, Malte; Lang, Roman; Bytof, Gerhard; Stiebitz, Herbert; Lantz, Ingo; Hofmann, Thomas; Somoza, Veronika

    2014-06-01

    Coffee consumption sometimes is associated with symptoms of stomach discomfort. This work aimed to elucidate whether two coffee beverages, containing similar amounts of caffeine, but differing in their concentrations of (β) N-alkanoyl-5-hydroxytryptamides (C5HTs), chlorogenic acids (CGAs), trigonelline, and N-methylpyridinium (N-MP) have different effects on gastric acid secretion in healthy volunteers. The intragastric pH after administration of bicarbonate with/without 200 mL of a coffee beverage prepared from a market blend or dark roast blend was analyzed in nine healthy volunteers. Coffee beverages were analyzed for their contents of C5HT, N-MP, trigonelline, CGAs, and caffeine using HPLC-DAD and HPLC-MS/MS. Chemical analysis revealed higher concentrations of N-MP for the dark brown blend (87 mg/L) compared to the market blend coffee (29 mg/L), whereas concentrations of C5HT (0.012 versus 0.343 mg/L), CGAs (323 versus 1126 mg/L), and trigonelline (119 versus 343 mg/L) were lower, and caffeine concentrations were similar (607 versus 674 mg/mL). Gastric acid secretion was less effectively stimulated after administration of the dark roast blend coffee compared to the market blend. Future studies are warranted to verify whether a high ratio of N-MP to C5HT and CGAs is beneficial for reducing coffee-associated gastric acid secretion. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Chenodeoxycholic acid stimulates glucagon-like peptide-1 secretion in patients after Roux-en-Y gastric bypass

    DEFF Research Database (Denmark)

    Nielsen, Signe; Svane, Maria S; Kuhre, Rune E

    2017-01-01

    (BMI 29.1 ± 1.2, age 37.0 ± 3.2 years, time from RYGB 32.3 ± 1.1 months, weight loss after RYGB 37.0 ± 3.1 kg) were studied in a placebo-controlled, crossover-study. On three different days, participants ingested (1) placebo (water), (2) UDCA 750 mg, (3) CDCA 1250 mg (highest recommended doses). Oral...... intake of CDCA increased plasma concentrations of GLP-1, C-peptide, glucagon, peptide YY, neurotensin, total bile acids, and fibroblast growth factor 19 significantly compared with placebo (all P

  5. Lack of effect of synthetic human gastric inhibitory polypeptide and glucagon-like peptide 1 [7-36 amide] infused at near-physiological concentrations on pentagastrin-stimulated gastric acid secretion in normal human subjects

    DEFF Research Database (Denmark)

    Nauck, M A; Bartels, E; Orskov, C

    1992-01-01

    -stimulated (0.1 micrograms/kg/h from -90 to 120 min) gastric volume, acid and chloride output, on separate occasions, synthetic human GIP (1 pmol/kg/min) and/or GLP-1 [7-36 amide] (0.3 pmol/kg/min) or placebo (0.9% NaCl with 1% albumin) were infused intravenously (from -30 to 120 min) in 9 healthy volunteers...... secretion). In conclusion, (penta)gastrin-stimulated gastric acid secretion is not inhibited by physiological circulating concentrations of GIP or GLP-1 [7-36 amide]. Therefore, the insulinotropic action of these intestinal hormones is physiologically more important than their possible role...

  6. Ultraviolet light and ozone stimulate accumulation of salicylic acid, pathogenesis-related proteins and virus resistance in tobacco

    International Nuclear Information System (INIS)

    Yalpani, N.; Enyedi, A.J.; León, J.; Raskin, I.

    1994-01-01

    In tobacco (Nicotiana tabacum L. cv. Xanthinc), salicylic acid (SA) levels increase in leaves inoculated by necrotizing pathogens and in healthy leaves located above the inoculated site. Systemic SA increase may trigger disease resistance and synthesis of pathogenesis-related proteins (PR proteins). Here we report that ultraviolet (UV)-C light or ozone induced biochemical responses similar to those induced by necrotizing pathogens. Exposure of leaves to UV-C light or ozone resulted in a transient ninefold increase in SA compared to controls. In addition, in UV-light-irradiated plants, SA increased nearly fourfold to 0.77 μg·g −1 fresh weight in leaves that were shielded from UV light. Increased SA levels were accompanied by accumulation of an SA conjugate and by an increase in the activity of benzoic acid 2-hydroxylase which catalyzes SA biosynthesis. In irradiated and in unirradiated leaves of plants treated with UV light, as well as in plants fumigated with ozone, PR proteins 1a and 1b accumulated. This was paralleled by the appearance of induced resistance to a subsequent challenge with tobacco mosaic virus. The results suggest that UV light, ozone fumigation and tobacco mosaic virus can activate a common signal-transduction pathway that leads to SA and PR-protein accumulation and increased disease resistance. (author)

  7. Multi-imaging of Cytokinin and Abscisic Acid on the Roots of Rice (Oryza sativa) Using Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry.

    Science.gov (United States)

    Shiono, Katsuhiro; Hashizaki, Riho; Nakanishi, Toyofumi; Sakai, Tatsuko; Yamamoto, Takushi; Ogata, Koretsugu; Harada, Ken-Ichi; Ohtani, Hajime; Katano, Hajime; Taira, Shu

    2017-09-06

    Plant hormones act as important signaling molecules that regulate responses to abiotic stress as well as plant growth and development. Because their concentrations of hormones control the physiological responses in the target tissue, it is important to know the distributions and concentrations in the tissues. However, it is difficult to determine the hormone concentration on the plant tissue as a result of the limitations of conventional methods. Here, we report the first multi-imaging of two plant hormones, one of cytokinin [i.e., trans-zeatin (tZ)] and abscisic acid (ABA) using a new technology, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) imaging. Protonated signals of tZ (m/z 220.1) and ABA (m/z 265.3) were chosen on longitudinal sections of rice roots for MS imaging. tZ was broadly distributed about 40 mm behind the root apex but was barely detectable at the apex, whereas ABA was mainly detected at the root apex. Multi-imaging using MALDI-TOF-MS enabled the visualization of the localization and quantification of plant hormones. Thus, this tool is applicable to a wide range of plant species growing under various environmental conditions.

  8. Reduction of inflammatory responses and enhancement of extracellular matrix formation by vanillin-incorporated poly(lactic-co-glycolic acid) scaffolds.

    Science.gov (United States)

    Lee, Yujung; Kwon, Jeongil; Khang, Gilson; Lee, Dongwon

    2012-10-01

    Vanillin is one of the major components of vanilla, a commonly used flavoring agent and preservative and is known to exert potent antioxidant and anti-inflammatory activities. In this work, vanillin-incorporated poly(lactic-co-glycolic acid) (PLGA) films and scaffolds were fabricated to evaluate the effects of vanillin on the inflammatory responses and extracellular matrix (ECM) formation in vitro and in vivo. The incorporation of vanillin to PLGA films induced hydrophilic nature, resulting in the higher cell attachment and proliferation than the pure PLGA film. Vanillin also reduced the generation of reactive oxygen species (ROS) in cells cultured on the pure PLGA film and significantly inhibited the PLGA-induced inflammatory responses in vivo, evidenced by the reduced accumulation of inflammatory cells and thinner fibrous capsules. The effects of vanillin on the ECM formation were evaluated using annulus fibrous (AF) cell-seeded porous PLGA/vanillin scaffolds. PLGA/vanillin scaffolds elicited the more production of glycosaminoglycan and collagen than the pure PLGA scaffold, in a concentration-dependent manner. Based on the low level of inflammatory responses and enhanced ECM formation, vanillin-incorporated PLGA constructs make them promising candidates in the future biomedical applications.

  9. Reduction of Inflammatory Responses and Enhancement of Extracellular Matrix Formation by Vanillin-Incorporated Poly(Lactic-co-Glycolic Acid) Scaffolds

    Science.gov (United States)

    Lee, Yujung; Kwon, Jeongil; Khang, Gilson

    2012-01-01

    Vanillin is one of the major components of vanilla, a commonly used flavoring agent and preservative and is known to exert potent antioxidant and anti-inflammatory activities. In this work, vanillin-incorporated poly(lactic-co-glycolic acid) (PLGA) films and scaffolds were fabricated to evaluate the effects of vanillin on the inflammatory responses and extracellular matrix (ECM) formation in vitro and in vivo. The incorporation of vanillin to PLGA films induced hydrophilic nature, resulting in the higher cell attachment and proliferation than the pure PLGA film. Vanillin also reduced the generation of reactive oxygen species (ROS) in cells cultured on the pure PLGA film and significantly inhibited the PLGA-induced inflammatory responses in vivo, evidenced by the reduced accumulation of inflammatory cells and thinner fibrous capsules. The effects of vanillin on the ECM formation were evaluated using annulus fibrous (AF) cell-seeded porous PLGA/vanillin scaffolds. PLGA/vanillin scaffolds elicited the more production of glycosaminoglycan and collagen than the pure PLGA scaffold, in a concentration-dependent manner. Based on the low level of inflammatory responses and enhanced ECM formation, vanillin-incorporated PLGA constructs make them promising candidates in the future biomedical applications. PMID:22551555

  10. Caffeic Acid Phenethyl Ester Inhibits Oral Cancer Cell Metastasis by Regulating Matrix Metalloproteinase-2 and the Mitogen-Activated Protein Kinase Pathway

    Directory of Open Access Journals (Sweden)

    Chih-Yu Peng

    2012-01-01

    Full Text Available Caffeic acid phenethyl ester (CAPE, an active component extracted from honeybee hives, exhibits anti-inflammatory and anticancer activities. However, the molecular mechanism by which CAPE affects oral cancer cell metastasis has yet to be elucidated. In this study, we investigated the potential mechanisms underlying the effects of CAPE on the invasive ability of SCC-9 oral cancer cells. Results showed that CAPE attenuated SCC-9 cell migration and invasion at noncytotoxic concentrations (0 μM to 40 μM. Western blot and gelatin zymography analysis findings further indicated that CAPE downregulated matrix metalloproteinase-2 (MMP-2 protein expression and inhibited its enzymatic activity. CAPE exerted its inhibitory effects on MMP-2 expression and activity by upregulating tissue inhibitor of metalloproteinase-2 (TIMP-2 and potently decreased migration by reducing focal adhesion kinase (FAK phosphorylation and the activation of its downstream signaling molecules p38/MAPK and JNK. These data indicate that CAPE could potentially be used as a chemoagent to prevent oral cancer metastasis.

  11. Studies on Multifunctional Effect of All-Trans Retinoic Acid (ATRA on Matrix Metalloproteinase-2 (MMP-2 and Its Regulatory Molecules in Human Breast Cancer Cells (MCF-7

    Directory of Open Access Journals (Sweden)

    Anindita Dutta

    2009-01-01

    Full Text Available Background. Vitamin A derivative all-trans retinoic acid (ATRA is considered as a potent chemotherapeutic drug for its capability of regulating cell growth and differentiation. We studied the effect of ATRA on MMP-2 in MCF-7, human breast cancer cells, and the probable signaling pathways which are affected by ATRA on regulating pro-MMP-2 activity and expression. Methods. Gelatin zymography, RT-PCR, ELISA, Western blot, Immunoprecipitation, and Cell adhesion assay are used. Results. Gelatin zymography showed that ATRA caused a dose-dependent inhibition of pro-MMP-2 activity. ATRA treatment downregulates the expression of MT1-MMP, EMMPRIN, FAK, NF-kB, and p-ERK. However, expression of E-cadherin, RAR, and CRABP increased upon ATRA treatment. Binding of cells to extra cellular matrix (ECM protein fibronectin reduced significantly after ATRA treatment. Conclusions. The experimental findings clearly showed the inhibition of MMP-2 activity upon ATRA treatment. This inhibitory effect of ATRA on MMP-2 activity in human breast cancer cells (MCF-7 may result due to its inhibitory effect on MT1-MMP, EMMPRIN, and upregulation of TIMP-2. This study is focused on the effect of ATRA on MMP, MMP-integrin-E-cadherin interrelationship, and also the effect of the drug on different signaling molecules which may involve in the progression of malignant tumor development.

  12. Studies on collagen-tannic acid-collagenase ternary system: Inhibition of collagenase against collagenolytic degradation of extracellular matrix component of collagen.

    Science.gov (United States)

    Krishnamoorthy, Ganesan; Sehgal, Praveen Kumar; Mandal, Asit Baran; Sadulla, Sayeed

    2012-06-01

    We report the detailed studies on the inhibitory effect of tannic acid (TA) on Clostridium histolyticum collagenase (ChC) activity against degradation of extracellular matrix component of collagen. The TA treated collagen exhibited 64% resistance against collagenolytic hydrolysis by ChC, whereas direct interaction of TA with ChC exhibited 99% inhibition against degradation of collagen and the inhibition was found to be concentration dependant. The kinetic inhibition of ChC has been deduced from the extent of hydrolysis of N-[3-(2-furyl) acryloyl]-Leu-Gly-Pro-Ala (FALGPA). This data provides a selective competitive mode of inhibition on ChC activity seems to be influenced strongly by the nature and structure of TA. TA showed inhibitor activity against the ChC by molecular docking method. This result demonstrated that TA containing digalloyl radical possess the ability to inhibit the ChC. The inhibition of ChC in gaining new insight into the mechanism of stabilization of collagen by TA is discussed.

  13. Probing molecular interactions of poly(styrene-co-maleic acid) with lipid matrix models to interpret the therapeutic potential of the co-polymer.

    Science.gov (United States)

    Banerjee, Shubhadeep; Pal, Tapan K; Guha, Sujoy K

    2012-03-01

    To understand and maximize the therapeutic potential of poly(styrene-co-maleic acid) (SMA), a synthetic, pharmacologically-active co-polymer, its effect on conformation, phase behavior and stability of lipid matrix models of cell membranes were investigated. The modes of interaction between SMA and lipid molecules were also studied. While, attenuated total reflection-Fourier-transform infrared (ATR-FTIR) and static (31)P nuclear magnetic resonance (NMR) experiments detected SMA-induced conformational changes in the headgroup region, differential scanning calorimetry (DSC) studies revealed thermotropic phase behavior changes of the membranes. (1)H NMR results indicated weak immobilization of SMA within the bilayers. Molecular interpretation of the results indicated the role of hydrogen-bond formation and hydrophobic forces between SMA and zwitterionic phospholipid bilayers. The extent of membrane fluidization and generation of isotropic phases were affected by the surface charge of the liposomes, and hence suggested the role of electrostatic interactions between SMA and charged lipid headgroups. SMA was thus found to directly affect the structural integrity of model membranes. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Selective extraction of U(VI), Th(IV), and La(III) from acidic matrix solutions and environmental samples using chemically modified Amberlite XAD-16 resin

    Energy Technology Data Exchange (ETDEWEB)

    Prabhakaran, D.; Subramanian, M.S. [Department of Chemistry, Indian Institute of Technology, 600 036, Chennai (India)

    2004-06-01

    A new grafted polymer has been developed by the chemical modification of Amberlite XAD-16 (AXAD-16) polymeric matrix with [(2-dihydroxyarsinoylphenylamino)methyl]phosphonic acid (AXAD-16-AsP). The modified polymer was characterized by a combination of {sup 13}C CPMAS and {sup 31}P solid-state NMR, Fourier transform-NIR-FIR-Raman spectroscopy, CHNPS elemental analysis, and thermogravimetric analysis (TGA). The distribution studies for the extraction of U(VI), Th(IV), and La(III) from acidic solutions were performed using an AXAD-16-AsP-packed chromatographic column. The influences of various physiochemical parameters on analyte recovery were optimized by both static and dynamic methods. Accordingly, even under high acidities (>4 M), good distribution ratio (D) values (10{sup 2}-10{sup 4}) were achieved for all the analytes. Metal ion desorption was effective using 1 mol L{sup -1} (NH{sub 4}){sub 2}CO{sub 3}. From kinetic studies, a time duration of <15 min was sufficient for complete metal ion saturation of the resin phase. The maximum metal sorption capacities were found to be 0.25, 0.13, and 1.49 mmol g{sup -1} for U(VI); 0.47, 0.39, and 1.40 mmol g{sup -1} for Th(IV); and 1.44, 1.48, and 1.12 mmol g{sup -1} for La(III), in the presence of 2 mol L{sup -1} HNO{sub 3}, 2 mol L{sup -1} HCl, and under pH conditions, respectively. The analyte selectivity of the grafted polymer was tested in terms of interfering species tolerance studies. The system showed an enrichment factor of 365, 300, and 270 for U(VI), Th(IV), and La(III), and the limit of analyte detection was in the range of 18-23 ng mL{sup -1}. The practical applicability of the polymer was tested with synthetic nuclear spent fuel and seawater mixtures, natural water, and geological samples. The RSD of the total analytical procedure was within 4.9%, thus confirming the reliability of the developed method. (orig.)

  15. Study on physical and electrostatic interactions of counterions in poly(perfluorosulfonic) acid matrix: Characterization of diffusion properties of membrane using radiotracers

    International Nuclear Information System (INIS)

    Suresh, G.; Sodaye, Suparna; Scindia, Y.M.; Pandey, A.K.; Goswami, A.

    2007-01-01

    The self-diffusion coefficients of water and ions were used to study the physical (tortuosity) and electrostatic interactions of counterions in poly(perfluorosulfonic) acid membrane (Nafion-117) matrix. The self-diffusion coefficients of water (D H 2 O m ) were measured in the water swollen Nafion-117 membrane with Zn 2+ , Ca 2+ , Sr 2+ , and Fe 2+ counterions by analyzing the experimental exchange rates between tritium tagged water (HTO) in membrane and equilibrating water. In order to study the effects of equilibrating solution, the HTO-desorption rate profiles between the membrane samples in H + or Cs + forms and equilibrating solution containing CsCl or HCl (0.25mol/L) were measured. It was observed that the HTO-exchange rate profile was slower in case of membrane sample in Cs + -from equilibrated with salt/acid solution than that equilibrated with deionized water in same ionic form. However, HTO-exchange rate profile did not alter in case of H + -form of membrane on equilibration with salt or acid solution. The variation of lnD H 2 O m with polymer volume function V p /(1-V p ), where V p is polymer volume fraction, indicated that: (i) D H 2 O m in the membrane with multivalent counterions was lower than that reported for membrane with monovalent counterions at same V p , and (ii) the linear trends observed in variation of lnD H 2 O m with V p /(1-V p ) for multivalent and monovalent counterions were significantly different. The values of D H 2 O m in membrane normalized with D H 2 O m at V p =0 were taken as an estimate of the tortuosity factor for self-diffusion of ions in the membrane matrix. The self-diffusion coefficients of ions reported in the literature along with tortuosity factor obtained from D H 2 O m in the corresponding ionic forms of the membrane were analyzed to obtain the charge (Z i ) independent electrostatic interaction parameter g(φ) of monovalent and divalent ions in the membrane. This analysis indicated that g(φ) also vary

  16. Mammalian target of rapamycin complex 1 activation is required for the stimulation of human skeletal muscle protein synthesis by essential amino acids.

    Science.gov (United States)

    Dickinson, Jared M; Fry, Christopher S; Drummond, Micah J; Gundermann, David M; Walker, Dillon K; Glynn, Erin L; Timmerman, Kyle L; Dhanani, Shaheen; Volpi, Elena; Rasmussen, Blake B

    2011-05-01

    The relationship between mammalian target of rapamycin complex 1 (mTORC1) signaling and muscle protein synthesis during instances of amino acid surplus in humans is based solely on correlational data. Therefore, the goal of this study was to use a mechanistic approach specifically designed to determine whether increased mTORC1 activation is requisite for the stimulation of muscle protein synthesis following L-essential amino acid (EAA) ingestion in humans. Examination of muscle protein synthesis and signaling were performed on vastus lateralis muscle biopsies obtained from 8 young (25 ± 2 y) individuals who were studied prior to and following ingestion of 10 g of EAA during 2 separate trials in a randomized, counterbalanced design. The trials were identical except during 1 trial, participants were administered a single oral dose of a potent mTORC1 inhibitor (rapamycin) prior to EAA ingestion. In response to EAA ingestion, an ~60% increase in muscle protein synthesis was observed during the control trial, concomitant with increased phosphorylation of mTOR (Ser(2448)), ribosomal S6 kinase 1 (Thr(389)), and eukaryotic initiation factor 4E binding protein 1 (Thr(37/46)). In contrast, prior administration of rapamycin completely blocked the increase in muscle protein synthesis and blocked or attenuated activation of mTORC1-signaling proteins. The inhibition of muscle protein synthesis and signaling was not due to differences in either extracellular or intracellular amino acid availability, because these variables were similar between trials. These data support a fundamental role for mTORC1 activation as a key regulator of human muscle protein synthesis in response to increased EAA availability. This information will be useful in the development of evidence-based nutritional therapies targeting mTORC1 to counteract muscle wasting associated with numerous clinical conditions.

  17. The moderate essential amino acid restriction entailed by low-protein vegan diets may promote vascular health by stimulating FGF21 secretion.

    Science.gov (United States)

    McCarty, Mark F

    2016-02-12

    The serum total and LDL cholesterol levels of long-term vegans tend to be very low. The characteristically low ratio of saturated to unsaturated fat in vegan diets, and the absence of cholesterol in such diets, clearly contribute to this effect. But there is reason to suspect that the quantity and composition of dietary protein also play a role in this regard. Vegan diets of moderate protein intake tend to be relatively low in certain essential amino acids, and as a result may increase hepatic activity of the kinase GCN2, which functions as a gauge of amino acid status. GCN2 activation boosts the liver's production of fibroblast growth factor 21 (FGF21), a factor which favorably affects serum lipids and metabolic syndrome. The ability of FGF21 to decrease LDL cholesterol has now been traced to at least two mechanisms: a suppression of hepatocyte expression of sterol response element-binding protein-2 (SREBP-2), which in turn leads to a reduction in cholesterol synthesis; and up-regulated expression of hepatocyte LDL receptors, reflecting inhibition of a mechanism that promotes proteasomal degradation of these receptors. In mice, the vascular benefits of FGF21 are also mediated by favorable effects on adipocyte function - most notably, increased adipocyte secretion of adiponectin, which directly exerts anti-inflammatory effects on the vasculature which complement the concurrent reduction in LDL particles in preventing or reversing atherosclerosis. If, as has been proposed, plant proteins preferentially stimulate glucagon secretion owing to their amino acid composition, this would represent an additional mechanism whereby plant protein promotes FGF21 activity, as glucagon acts on the liver to boost transcription of the FGF21 gene.

  18. Supplementation with linoleic acid-rich soybean oil stimulates macrophage foam cell formation via increased oxidative stress and diacylglycerol acyltransferase1-mediated triglyceride biosynthesis.

    Science.gov (United States)

    Rom, Oren; Jeries, Helana; Hayek, Tony; Aviram, Michael

    2017-01-02

    During the last decades there has been a staggering rise in human consumption of soybean oil (SO) and its major polyunsaturated fatty acid linoleic acid (LA). The role of SO or LA in cardiovascular diseases is highly controversial, and their impact on macrophage foam cell formation, the hallmark of early atherogenesis, is unclear. To investigate the effects of high SO or LA intake on macrophage lipid metabolism and the related mechanisms of action, C57BL/6 mice were orally supplemented with increasing levels of SO-based emulsion or equivalent levels of purified LA for 1 month, followed by analyses of lipid accumulation and peroxidation in aortas, serum and in peritoneal macrophages (MPM) of the mice. Lipid peroxidation and triglyceride mass in aortas from SO or LA supplemented mice were dose-dependently and significantly increased. In MPM from SO or LA supplemented mice, lipid peroxides were significantly increased and a marked accumulation of cellular triglycerides was found in accordance with enhanced triglyceride biosynthesis rate and overexpression of diacylglycerol acyltransferase1 (DGAT1), the key enzyme in triglyceride biosynthesis. In cultured J774A.1 macrophages treated with SO or LA, triglyceride accumulated via increased oxidative stress and a p38 mitogen-activated protein kinase (MAPK)-mediated overexpression of DGAT1. Accordingly, anti-oxidants (pomegranate polyphenols), inhibition of p38 MAPK (by SB202190) or DGAT1 (by oleanolic acid), all significantly attenuated SO or LA-induced macrophage triglyceride accumulation. These findings reveal novel mechanisms by which supplementation with SO or LA stimulate macrophage foam cell formation, suggesting a pro-atherogenic role for overconsumption of SO or LA. © 2016 BioFactors, 43(1):100-116, 2017. © 2016 International Union of Biochemistry and Molecular Biology.

  19. Indole-3-butyric acid promotes adventitious rooting in Arabidopsis thaliana thin cell layers by conversion into indole-3-acetic acid and stimulation of anthranilate synthase activity.

    Science.gov (United States)

    Fattorini, L; Veloccia, A; Della Rovere, F; D'Angeli, S; Falasca, G; Altamura, M M

    2017-07-11

    Indole-3-acetic acid (IAA), and its precursor indole-3-butyric acid (IBA), control adventitious root (AR) formation in planta. Adventitious roots are also crucial for propagation via cuttings. However, IBA role(s) is/are still far to be elucidated. In Arabidopsis thaliana stem cuttings, 10 μM IBA is more AR-inductive than 10 μM IAA, and, in thin cell layers (TCLs), IBA induces ARs when combined with 0.1 μM kinetin (Kin). It is unknown whether arabidopsis TCLs produce ARs under IBA alone (10 μM) or IAA alone (10 μM), and whether they contain endogenous IAA/IBA at culture onset, possibly interfering with the exogenous IBA/IAA input. Moreover, it is unknown whether an IBA-to-IAA conversion is active in TCLs, and positively affects AR formation, possibly through the activity of the nitric oxide (NO) deriving from the conversion process. Revealed undetectable levels of both auxins at culture onset, showing that arabidopsis TCLs were optimal for investigating AR-formation under the total control of exogenous auxins. The AR-response of TCLs from various ecotypes, transgenic lines and knockout mutants was analyzed under different treatments. It was shown that ARs are better induced by IBA than IAA and IBA + Kin. IBA induced IAA-efflux (PIN1) and IAA-influx (AUX1/LAX3) genes, IAA-influx carriers activities, and expression of ANTHRANILATE SYNTHASE -alpha1 (ASA1), a gene involved in IAA-biosynthesis. ASA1 and ANTHRANILATE SYNTHASE -beta1 (ASB1), the other subunit of the same enzyme, positively affected AR-formation in the presence of exogenous IBA, because the AR-response in the TCLs of their mutant wei2wei7 was highly reduced. The AR-response of IBA-treated TCLs from ech2ibr10 mutant, blocked into IBA-to-IAA-conversion, was also strongly reduced. Nitric oxide, an IAA downstream signal and a by-product of IBA-to-IAA conversion, was early detected in IAA- and IBA-treated TCLs, but at higher levels in the latter explants. Altogether, results showed that IBA induced

  20. A multi-matrix HILIC-MS/MS method for the quantitation of endogenous small molecule neurological biomarker N-acetyl aspartic acid (NAA).

    Science.gov (United States)

    Sangaraju, Dewakar; Shahidi-Latham, Sheerin K; Burgess, Braydon L; Dean, Brian; Ding, Xiao

    2017-06-05

    A multi-matrix hydrophilic interaction liquid chromatography tandem mass spectrometric method (HILIC-MS/MS) was developed for the quantitation of N-Acetyl Aspartic acid (NAA) using stable isotope labeled internal standard, D3-NAA in various biological matrices such as human plasma, human CSF, mouse plasma, brain and spinal cord. A high throughput 96-well plate format supported liquid extraction (SLE) procedure was developed and used for sample preparation. Mass spectrometric analysis of NAA was performed using selected reaction monitoring transitions in positive electrospray ionization mode. As NAA is endogenously present, a surrogate matrix approach was used for quantitation of NAA and the method was qualified over linear calibration curve range of 0.01-10μg/mL. Intra and inter assay precision indicated by percent relative standard deviation (%RSD) was less than 7.1% for low, medium, medium high and high QCs. The accuracy of the method ranged from 92.6-107.0% of nominal concentration for within-run and between-run for the same QCs. Extraction recovery of NAA and D3-NAA was greater than 76%. Stability of NAA was established in the above biological matrices under bench top (RT, 5h), freeze thaw (-20±10°C, 3 cycles) and moues/human plasma sample collection (Wet ice, RT) conditions. HILIC-MS/MS method was then used to quantify and compare the NAA levels in human plasma and CSF of ALS patients versus control human subjects. NAA CSF levels in control human subjects (73.3±31.0ng/mL,N=10) were found to be slightly higher than ALS patients (46.1±22.6ng/mL, N=10) (P=0.04). No differences were observed in NAA plasma levels in human control subjects (49.7±13.8ng/mL,N=9) as compared to ALS patients (49.6±8.1ng/mL, N=10) (P=0.983). NAA endogenous concentrations in mouse plasma, brain and spinal cord were found to be 243.8±56.8ng/mL (N=6), 1029.8±115.2μg/g tissue weight (N=5) and 487.6±178.4μg/g tissue weight (N=5) respectively. Copyright © 2017 Elsevier B.V. All

  1. Glucose-stimulated insulin response in pregnant sheep following acute suppression of plasma non-esterified fatty acid concentrations

    Directory of Open Access Journals (Sweden)

    Sriskandarajah Nadarajah

    2004-09-01

    Full Text Available Abstract Background Elevated non-esterified fatty acids (NEFA concentrations in non-pregnant animals have been reported to decrease pancreatic responsiveness. As ovine gestation advances, maternal insulin concentrations fall and NEFA concentrations increase. Experiments were designed to examine if the pregnancy-associated rise in NEFA concentration is associated with a reduced pancreatic sensitivity to glucose in vivo. We investigated the possible relationship of NEFA concentrations in regulating maternal insulin concentrations during ovine pregnancy at three physiological states, non-pregnant, non-lactating (NPNL, 105 and 135 days gestational age (dGA, term 147+/- 3 days. Methods The plasma concentrations of insulin, growth hormone (GH and ovine placental lactogen (oPL were determined by double antibody radioimmunoassay. Insulin responsiveness to glucose was measured using bolus injection and hyperglycaemic clamp techniques in 15 non-pregnant, non-lactating ewes and in nine pregnant ewes at 105 dGA and near term at 135 dGA. Plasma samples were also collected for hormone determination. In addition to bolus injection glucose and insulin Area Under Curve calculations, the Mean Plasma Glucose Increment, Glucose Infusion Rate and Mean Plasma Insulin Increment and Area Under Curve were determined for the hyperglycaemic clamp procedures. Statistical analysis of data was conducted with Students t-tests, repeated measures ANOVA and 2-way ANOVA. Results Maternal growth hormone, placental lactogen and NEFA concentrations increased, while basal glucose and insulin concentrations declined with advancing gestation. At 135 dGA following bolus glucose injections, peak insulin concentrations and insulin area under curve (AUC profiles were significantly reduced in pregnant ewes compared with NPNL control ewes (p Conclusions Results suggest that despite an acute suppression of circulating NEFA concentrations during pregnancy, the associated steroids and hormones

  2. Ascorbic acid transported by sodium-dependent vitamin C transporter 2 stimulates steroidogenesis in human choriocarcinoma cells.

    Science.gov (United States)

    Wu, Ximei; Iguchi, Takuma; Itoh, Norio; Okamoto, Kousuke; Takagi, Tatsuya; Tanaka, Keiichi; Nakanishi, Tsuyoshi

    2008-01-01

    Reduced vitamin C [ascorbic acid (AA)], which is taken up into cells by sodium-dependent vitamin C transporter (SVCT) 1 and 2, is believed to be important for hormone synthesis, but its role in generating placental steroids needed to maintain pregnancy and fetal development is not clear. To determine the steroidogenic effect of AA and the role of SVCT2 in AA-induced steroidogenesis, we tested the effects of AA treatment and SVCT2 knockdown on steroidogenesis in human choriocarcinoma cell lines. AA treatment of JEG-3, BeWo, and JAR cells for 48-h dose dependently increased progesterone and estradiol levels. In JEG-3 cells, AA increased the mRNA expression of P450 cholesterol side-chain cleavage enzyme, 3beta-hydroxysteroid dehydrogenase type 1, and aromatase, key enzymes for steroidogenesis. Stable knockdown of SVCT2 in JEG-3 cells by retrovirally mediated RNA interference decreased the maximal velocity of AA uptake by approximately 50%, but apparent affinity values were not affected. SVCT2 knockdown in JEG-3 cells significantly suppressed the AA-induced mRNA expression of placental P450 cholesterol side-chain cleavage enzyme, 3beta-hydroxysteroid dehydrogenase type 1, and aromatase. This suppression of the AA-induced mRNA expression of steroidogenic enzymes subsequently decreased progesterone and estradiol production. In addition, inhibition of MAPK kinase-ERK signaling, which is a major pathway for AA-regulated gene expression, failed to affect AA-induced steroidogenesis. Our observations indicate that SVCT2-mediated AA uptake into cells is necessary for AA-induced steroidogenesis in human choriocarcinoma cell, but MAPK kinase-ERK signaling is not involved in AA-induced steroidogenesis.

  3. Matrix metalloproteinase (MMP-9 in cancer-associated fibroblasts (CAFs is suppressed by omega-3 polyunsaturated fatty acids in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Ayumi Taguchi

    Full Text Available Cancer associated fibroblasts (CAFs are responsible for tumor growth, angiogenesis, invasion, and metastasis. Matrix metalloproteinase (MMP-9 secreted from cancer stroma populated by CAFs is a prerequisite for cancer angiogenesis and metastasis. Omega-3 polyunsaturated fatty acids (omega-3 PUFA have been reported to have anti-tumor effects on diverse types of malignancies. Fat-1 mice, which can convert omega-6 to omega-3 PUFA independent of diet, are useful to investigate the functions of endogenous omega-3 PUFA. To examine the effect of omega-3 PUFA on tumorigenesis, TC-1 cells, a murine epithelial cell line immortalized by human papillomavirus (HPV oncogenes, were injected subcutaneously into fat-1 or wild type mice. Tumor growth and angiogenesis of the TC-1 tumor were significantly suppressed in fat-1 compared to wild type mice. cDNA microarray of the tumors derived from fat-1 and wild type mice revealed that MMP-9 is downregulated in fat-1 mice. Immunohistochemical study demonstrated immunoreactivity for MMP-9 in the tumor stromal fibroblasts was diffusely positive in wild type whereas focal in fat-1 mice. MMP-9 was expressed in primary cultured fibroblasts isolated from fat-1 and wild type mice but was not expressed in TC-1 cells. Co-culture of fibroblasts with TC-1 cells enhanced the expression and the proteinase activity of MMP-9, although the protease activity of MMP-9 in fat-1-derived fibroblasts was lower than that in wild type fibroblasts. Our data suggests that omega-3 PUFAs suppress MMP-9 induction and tumor angiogenesis. These findings may provide insight into mechanisms by which omega-3 PUFAs exert anti-tumor effects by modulating tumor microenvironment.

  4. Effect of All-Trans Retinoic Acid (ATRA against expression of Matrix Metalloproteinase-2 (MMP-2 in model mice (Rattus norvegicus periodontitis

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    Ilma Soraya

    2017-08-01

    Full Text Available Introduction: Periodontitis is a condition of inflammation of the tooth supporting tissues generally caused by bacteria Phorphyromonas gingivalis (Pg. and is usually characterized by the occurrence of the alveolar bone resorption. Matrix metalloproteinase-2 (MMP-2 is an enzyme that plays an important role in inflammatory conditions. All-trans retinoic acid (ATRA is a metabolite of vitamin A which plays a role in healing the inflamed tissue and maintain the immune system. The purpose of this study was to determine the effect of ATRA on the expression of MMP-2 in mouse models Rattus norvegicus of periodontitis. Methods: Experimental laboratory by using post test only with control group design. This study used 25 male Wistar mice (Rattus norvegicus that divided into 5 groups. Group 1 (G1 is a group of healthy mice, group 2 (G2 is a group of sick mice as induced periodontitis without treatment, group 3 (G3 is a group of periodontitis mice treated with 5 mg/kg dose of ATRA, group 4 (G4 is a group of periodontitis mice treated with 10 mg/kg dose of ATRA, group 5 (G5 is a group of periodontitis mice treated with 20 mg/kg dose of ATRA. Periodontitis induction was induced by Pg. bacteria every 3 days for 28 days and followed by administration of ATRA for 7 days. Expression of MMP-2 from gingival tissues and periodontal ligament was obtained by immunohistochemical methods. Results were analyzed using the Shapiro-Wilk Test and Mann-Whitney Test. Results: The results showed there were significant differences in the positive area of MMP-2 and MMP-2 color intensity (p < 0.05 between groups. Conclusion: ATRA dose of 20 mg/kg is the most effective dose in inhibiting the expression of MMP-2 in mice models of periodontitis when compared with the dose on other groups.

  5. Comparison of cellular effects of starch-coated SPIONs and poly(lactic-co-glycolic acid) matrix nanoparticles on human monocytes.

    Science.gov (United States)

    Gonnissen, Dominik; Qu, Ying; Langer, Klaus; Öztürk, Cengiz; Zhao, Yuliang; Chen, Chunying; Seebohm, Guiscard; Düfer, Martina; Fuchs, Harald; Galla, Hans-Joachim; Riehemann, Kristina

    Within the last years, progress has been made in the knowledge of the properties of medically used nanoparticles and their toxic effects, but still, little is known about their influence on cellular processes of immune cells. The aim of our comparative study was to present the influence of two different nanoparticle types on subcellular processes of primary monocytes and the leukemic monocyte cell line MM6. We used core-shell starch-coated superparamagnetic iron oxide nanoparticles (SPIONs) and matrix poly(lactic-co-glycolic acid) (PLGA) nanoparticles for our experiments. In addition to typical biocompatibility testing like the detection of necrosis or secretion of interleukins (ILs), we investigated the impact of these nanoparticles on the actin cytoskeleton and the two voltage-gated potassium channels Kv1.3 and Kv7.1. Induction of necrosis was not seen for PLGA nanoparticles and SPIONs in primary monocytes and MM6 cells. Likewise, no alteration in secretion of IL-1β and IL-10 was detected under the same experimental conditions. In contrast, IL-6 secretion was exclusively downregulated in primary monocytes after contact with both nanoparticles. Two-electrode voltage clamp experiments revealed that both nanoparticles reduce currents of the aforementioned potassium channels. The two nanoparticles differed significantly in their impact on the actin cytoskeleton, demonstrated via atomic force microscopy elasticity measurement and phalloidin staining. While SPIONs led to the disruption of the respective cytoskeleton, PLGA did not show any influence in both experimental setups. The difference in the effects on ion channels and the actin cytoskeleton suggests that nanoparticles affect these subcellular components via different pathways. Our data indicate that the alteration of the cytoskeleton and the effect on ion channels are new parameters that describe the influence of nanoparticles on cells. The results are highly relevant for medical application and further

  6. Insight into the heterogeneous adsorption of humic acid fluorescent components on multi-walled carbon nanotubes by excitation-emission matrix and parallel factor analysis.

    Science.gov (United States)

    Yang, Chenghu; Liu, Yangzhi; Cen, Qiulin; Zhu, Yaxian; Zhang, Yong

    2018-02-01

    The heterogeneous adsorption behavior of commercial humic acid (HA) on pristine and functionalized multi-walled carbon nanotubes (MWCNTs) was investigated by fluorescence excitation-emission matrix and parallel factor (EEM- PARAFAC) analysis. The kinetics, isotherms, thermodynamics and mechanisms of adsorption of HA fluorescent components onto MWCNTs were the focus of the present study. Three humic-like fluorescent components were distinguished, including one carboxylic-like fluorophore C1 (λ ex /λ em = (250, 310) nm/428nm), and two phenolic-like fluorophores, C2 (λ ex /λ em = (300, 460) nm/552nm) and C3 (λ ex /λ em = (270, 375) nm/520nm). The Lagergren pseudo-second-order model can be used to describe the adsorption kinetics of the HA fluorescent components. In addition, both the Freundlich and Langmuir models can be suitably employed to describe the adsorption of the HA fluorescent components onto MWCNTs with significantly high correlation coefficients (R 2 > 0.94, Padsorption affinity (K d ) and nonlinear adsorption degree from the HA fluorescent components to MWCNTs was clearly observed. The adsorption mechanism suggested that the π-π electron donor-acceptor (EDA) interaction played an important role in the interaction between HA fluorescent components and the three MWCNTs. Furthermore, the values of the thermodynamic parameters, including the Gibbs free energy change (ΔG°), enthalpy change (ΔH°) and entropy change (ΔS°), showed that the adsorption of the HA fluorescent components on MWCNTs was spontaneous and exothermic. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Matrix calculus

    CERN Document Server

    Bodewig, E

    1959-01-01

    Matrix Calculus, Second Revised and Enlarged Edition focuses on systematic calculation with the building blocks of a matrix and rows and columns, shunning the use of individual elements. The publication first offers information on vectors, matrices, further applications, measures of the magnitude of a matrix, and forms. The text then examines eigenvalues and exact solutions, including the characteristic equation, eigenrows, extremum properties of the eigenvalues, bounds for the eigenvalues, elementary divisors, and bounds for the determinant. The text ponders on approximate solutions, as well

  8. IL-1β and TNFα inhibit GPR120 (FFAR4) and stimulate GPR84 (EX33) and GPR41 (FFAR3) fatty acid receptor expression in human adipocytes: implications for the anti-inflammatory action of n-3 fatty acids.

    Science.gov (United States)

    Muredda, Laura; Kępczyńska, Małgorzata A; Zaibi, Mohamed S; Alomar, Suliman Y; Trayhurn, Paul

    2018-05-01

    Regulation of the expression of GPCR fatty acid receptor genes has been examined in human adipocytes differentiated in culture. TNFα and IL-1β induced a marked reduction in GPR120 expression, mRNA level falling 17-fold at 24 h in adipocytes incubated with TNFα. In contrast, GPR84 mRNA was dramatically increased by these cytokines (>500-fold for IL-1β at 4 h); GPR41 expression was also stimulated. Rosiglitazone did not affect GPR84 expression, but GPR120 and GPR41 expression increased. Dexamethasone, insulin, linoleic and docosahexaenoic acids (DHA), and TUG891 (GPR120 agonist) had little effect on GPR120 and GPR84 expression. TUG891 did not attenuate the pro-inflammatory actions of TNFα and IL-1β. DHA slightly countered the actions of IL-1β on CCL2, IL6 and ADIPOQ expression, though not on secretion of these adipokines. GPR120 and GP84 gene expression in human adipocytes is highly sensitive to pro-inflammatory mediators; the inflammation-induced inhibition of GPR120 expression may compromise the anti-inflammatory action of GPR120 agonists.

  9. In-depth, high-accuracy proteomics of sea urchin tooth organic matrix

    Directory of Open Access Journals (Sweden)

    Mann Matthias

    2008-12-01

    Full Text Available Abstract Background The organic matrix contained in biominerals plays an important role in regulating mineralization and in determining biomineral properties. However, most components of biomineral matrices remain unknown at present. In sea urchin tooth, which is an important model for developmental biology and biomineralization, only few matrix components have been identified. The recent publication of the Strongylocentrotus purpuratus genome sequence rendered possible not only the identification of genes potentially coding for matrix proteins, but also the direct identification of proteins contained in matrices of skeletal elements by in-depth, high-accuracy proteomic analysis. Results We identified 138 proteins in the matrix of tooth powder. Only 56 of these proteins were previously identified in the matrices of test (shell and spine. Among the novel components was an interesting group of five proteins containing alanine- and proline-rich neutral or basic motifs separated by acidic glycine-rich motifs. In addition, four of the five proteins contained either one or two predicted Kazal protease inhibitor domains. The major components of tooth matrix were however largely identical to the set of spicule matrix proteins and MSP130-related proteins identified in test (shell and spine matrix. Comparison of the matrices of crushed teeth to intact teeth revealed a marked dilution of known intracrystalline matrix proteins and a concomitant increase in some intracellular proteins. Conclusion This report presents the most comprehensive list of sea urchin tooth matrix proteins available at present. The complex mixture of proteins identified may reflect many different aspects of the mineralization process. A comparison between intact tooth matrix, presumably containing odontoblast remnants, and crushed tooth matrix served to differentiate between matrix components and possible contributions of cellular remnants. Because LC-MS/MS-based methods directly

  10. The Exopolysaccharide Matrix

    Science.gov (United States)

    Koo, H.; Falsetta, M.L.; Klein, M.I.

    2013-01-01

    Many infectious diseases in humans are caused or exacerbated by biofilms. Dental caries is a prime example of a biofilm-dependent disease, resulting from interactions of microorganisms, host factors, and diet (sugars), which modulate the dynamic formation of biofilms on tooth surfaces. All biofilms have a microbial-derived extracellular matrix as an essential constituent. The exopolysaccharides formed through interactions between sucrose- (and starch-) and Streptococcus mutans-derived exoenzymes present in the pellicle and on microbial surfaces (including non-mutans) provide binding sites for cariogenic and other organisms. The polymers formed in situ enmesh the microorganisms while forming a matrix facilitating the assembly of three-dimensional (3D) multicellular structures that encompass a series of microenvironments and are firmly attached to teeth. The metabolic activity of microbes embedded in this exopolysaccharide-rich and diffusion-limiting matrix leads to acidification of the milieu and, eventually, acid-dissolution of enamel. Here, we discuss recent advances concerning spatio-temporal development of the exopolysaccharide matrix and its essential role in the pathogenesis of dental caries. We focus on how the matrix serves as a 3D scaffold for biofilm assembly while creating spatial heterogeneities and low-pH microenvironments/niches. Further understanding on how the matrix modulates microbial activity and virulence expression could lead to new approaches to control cariogenic biofilms. PMID:24045647

  11. Peroxidase enzymes regulate collagen extracellular matrix biosynthesis.

    Science.gov (United States)

    DeNichilo, Mark O; Panagopoulos, Vasilios; Rayner, Timothy E; Borowicz, Romana A; Greenwood, John E; Evdokiou, Andreas

    2015-05-01

    Myeloperoxidase and eosinophil peroxidase are heme-containing enzymes often physically associated with fibrotic tissue and cancer in various organs, without any direct involvement in promoting fibroblast recruitment and extracellular matrix (ECM) biosynthesis at these sites. We report herein novel findings that show peroxidase enzymes possess a well-conserved profibrogenic capacity to stimulate the migration of fibroblastic cells and promote their ability to secrete collagenous proteins to generate a functional ECM both in vitro and in vivo. Mechanistic studies conducted using cultured fibroblasts show that these cells are capable of rapidly binding and internalizing both myeloperoxidase and eosinophil peroxidase. Peroxidase enzymes stimulate collagen biosynthesis at a post-translational level in a prolyl 4-hydroxylase-dependent manner that does not require ascorbic acid. This response was blocked by the irreversible myeloperoxidase inhibitor 4-amino-benzoic acid hydrazide, indicating peroxidase catalytic activity is essential for collagen biosynthesis. These results suggest that peroxidase enzymes, such as myeloperoxidase and eosinophil peroxidase, may play a fundamental role in regulating the recruitment of fibroblast and the biosynthesis of collagen ECM at sites of normal tissue repair and fibrosis, with enormous implications for many disease states where infiltrating inflammatory cells deposit peroxidases. Copyright © 2015 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  12. Electric Stimulation of Ear Reduces the Effect of Toll-Like Receptor 4 Signaling Pathway on Kainic Acid-Induced Epileptic Seizures in Rats

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    En-Tzu Liao

    2018-01-01

    Full Text Available Epilepsy is a common clinical syndrome with recurrent neuronal discharges in the temporal lobe, cerebral cortex, and hippocampus. Clinical antiepileptic medicines are often ineffective or of little benefit in 30% of epileptic patients and usually cause severe side effects. Emerging evidence indicates the crucial role of inflammatory mediators in epilepsy. The current study investigates the role of toll-like receptor 4 (TLR4 and its underlying mechanisms in kainic acid- (KA- induced epileptic seizures in rats. Experimental KA injection successfully initiated an epileptic seizure accompanied by increased expression of TLR4 in the prefrontal cortex, hippocampus, and somatosensory cortex. In addition, calcium-sensitive phosphorylated Ca2+/calmodulin-dependent protein kinase II (pCaMKIIα increased after the initiation of the epileptic seizure. Furthermore, downstream-phosphorylated signal-regulated kinase (ERK, c-Jun NH2-terminal protein kinase (JNK, and p38 kinase simultaneously increased in these brain areas. Moreover, the transcriptional factor phosphorylated nuclear factor-κB (pNF-κB increased, suggesting that nucleus transcription was affected. Furthermore, the aforementioned molecules decreased by an electric stimulation (ES of either 2 Hz or 15 Hz of the ear in the three brain areas. Accordingly, we suggest that ES of the ear can successfully control epileptic seizures by regulating the TLR4 signaling pathway and has a therapeutic benefit in reducing epileptic seizures.

  13. Lauric Acid Stimulates Mammary Gland Development of Pubertal Mice through Activation of GPR84 and PI3K/Akt Signaling Pathway.

    Science.gov (United States)

    Meng, Yingying; Zhang, Jing; Zhang, Fenglin; Ai, Wei; Zhu, Xiaotong; Shu, Gang; Wang, Lina; Gao, Ping; Xi, Qianyun; Zhang, Yongliang; Liang, Xingwei; Jiang, Qingyan; Wang, Songbo

    2017-01-11

    It has been demonstrated that dietary fat affects pubertal mammary gland development. However, the role of lauric acid (LA) in this process remains unclear. Thus, this study aimed to investigate the effects of LA on mammary gland development in pubertal mice and to explore the underlying mechanism. In vitro, 100 μM LA significantly promoted proliferation of mouse mammary epithelial cell line HC11 by regulating expression of proliferative markers (cyclin D1/3, p21, PCNA). Meanwhile, LA activated the G protein-coupled receptor 84 (GPR84) and PI3K/Akt signaling pathway. In agreement, dietary 1% LA enhanced mammary duct development, increased the expression of GPR84 and cyclin D1, and activated PI3K/Akt in mammary gland of pubertal mice. Furthermore, knockdown of GPR84 or inhibition of PI3K/Akt totally abolished the promotion of HC11 proliferation induced by LA. These results showed that LA stimulated mammary gland development of pubertal mice through activation of GPR84 and PI3K/Akt signaling pathway.

  14. RhoA mediates the expression of acidic extracellular pH-induced matrix metalloproteinase-9 mRNA through phospholipase D1 in mouse metastatic B16-BL6 melanoma cells.

    Science.gov (United States)

    Maeda, Toyonobu; Yuzawa, Satoshi; Suzuki, Atsuko; Baba, Yuh; Nishimura, Yukio; Kato, Yasumasa

    2016-03-01

    Solid tumors are characterized by acidic extracellular pH (pHe). The present study examined the contribution of small GTP-binding proteins to phospholipase D (PLD) activation of acidic pHe-induced matrix metalloproteinase-9 (MMP-9) production. Acidic pHe-induced MMP-9 production was reduced by C3 exoenzyme, which inhibits the Rho family of GTPases; cytochalasin D, which inhibits actin reorganization; and simvastatin, which inhibits geranylgeranylation of Rho. Small interfering RNA (siRNA) against RhoA, but not against Rac1 or Cdc42, significantly inhibited acidic pHe induction of MMP-9. Pull-down assays showed that acidic pHe increased the activated form of RhoA. Forced expression of constitutively active RhoA induced MMP-9 production, even at neutral pHe. RhoA siRNA also reduced acidic pHe induced PLD activity. Specific inhibition of PLD1 and Pld1 gene knockout significantly reduced acidic pHe-induced MMP-9 expression. In contrast, PLD2 inhibition or knockout had no effect on MMP-9 expression. These findings suggested that RhoA-PLD1 signaling is involved in acidic pHe induction of MMP-9.

  15. Matrix thermalization

    International Nuclear Information System (INIS)

    Craps, Ben; Evnin, Oleg; Nguyen, Kévin

    2017-01-01

    Matrix quantum mechanics offers an attractive environment for discussing gravitational holography, in which both sides of the holographic duality are well-defined. Similarly to higher-dimensional implementations of holography, collapsing shell solutions in the gravitational bulk correspond in this setting to thermalization processes in the dual quantum mechanical theory. We construct an explicit, fully nonlinear supergravity solution describing a generic collapsing dilaton shell, specify the holographic renormalization prescriptions necessary for computing the relevant boundary observables, and apply them to evaluating thermalizing two-point correlation functions in the dual matrix theory.

  16. Matrix thermalization

    Science.gov (United States)

    Craps, Ben; Evnin, Oleg; Nguyen, Kévin

    2017-02-01

    Matrix quantum mechanics offers an attractive environment for discussing gravitational holography, in which both sides of the holographic duality are well-defined. Similarly to higher-dimensional implementations of holography, collapsing shell solutions in the gravitational bulk correspond in this setting to thermalization processes in the dual quantum mechanical theory. We construct an explicit, fully nonlinear supergravity solution describing a generic collapsing dilaton shell, specify the holographic renormalization prescriptions necessary for computing the relevant boundary observables, and apply them to evaluating thermalizing two-point correlation functions in the dual matrix theory.

  17. Matrix thermalization

    Energy Technology Data Exchange (ETDEWEB)

    Craps, Ben [Theoretische Natuurkunde, Vrije Universiteit Brussel (VUB), and International Solvay Institutes, Pleinlaan 2, B-1050 Brussels (Belgium); Evnin, Oleg [Department of Physics, Faculty of Science, Chulalongkorn University, Thanon Phayathai, Pathumwan, Bangkok 10330 (Thailand); Theoretische Natuurkunde, Vrije Universiteit Brussel (VUB), and International Solvay Institutes, Pleinlaan 2, B-1050 Brussels (Belgium); Nguyen, Kévin [Theoretische Natuurkunde, Vrije Universiteit Brussel (VUB), and International Solvay Institutes, Pleinlaan 2, B-1050 Brussels (Belgium)

    2017-02-08

    Matrix quantum mechanics offers an attractive environment for discussing gravitational holography, in which both sides of the holographic duality are well-defined. Similarly to higher-dimensional implementations of holography, collapsing shell solutions in the gravitational bulk correspond in this setting to thermalization processes in the dual quantum mechanical theory. We construct an explicit, fully nonlinear supergravity solution describing a generic collapsing dilaton shell, specify the holographic renormalization prescriptions necessary for computing the relevant boundary observables, and apply them to evaluating thermalizing two-point correlation functions in the dual matrix theory.

  18. Effects of amino acids on melanoma targeting and clearance properties of Tc-99m-labeled Arg-X-Asp-conjugated α-melanocyte stimulating hormone peptides.

    Science.gov (United States)

    Flook, Adam M; Yang, Jianquan; Miao, Yubin

    2013-11-14

    The purpose of this study was to examine the effects of amino acids on melanoma targeting and clearance properties of new (99m)Tc-labeled Arg-X-Asp-conjugated α-melanocyte stimulating hormone (α-MSH) peptides. RSD-Lys-(Arg(11))CCMSH {c[Arg-Ser-Asp-DTyr-Asp]-Lys-Cys-Cys-Glu-His-dPhe-Arg-Trp-Cys-Arg-Pro-Val-NH2}, RNleD-Lys-(Arg(11))CCMSH, RPheD-Lys-(Arg(11))CCMSH, and RdPheD-Lys-(Arg(11))CCMSH peptides were synthesized and evaluated for their melanocortin-1 (MC1) receptor binding affinities in B16/F1 melanoma cells. The biodistribution of (99m)Tc-RSD-Lys-(Arg(11))CCMSH, (99m)Tc-RFD-Lys-(Arg(11))CCMSH, and (99m)Tc-RfD-Lys-(Arg(11))CCMSH were determined in B16/F1 melanoma-bearing C57 mice. The substitution of Gly with Ser, Phe, and dPhe increased the MC1 receptor binding affinities of the peptides, whereas the substitution of Gly with Nle decreased the MC1 receptor binding affinity of the peptide. (99m)Tc-RSD-Lys-(Arg(11))CCMSH exhibited the highest melanoma uptake (18.01 ± 4.22% ID/g) and the lowest kidney and liver uptake among these (99m)Tc-peptides. The B16/F1 melanoma lesions could be clearly visualized by SPECT/CT using (99m)Tc-RSD-Lys-(Arg(11))CCMSH as an imaging probe. It is desirable to reduce the renal uptake of (99m)Tc-RSD-Lys-(Arg(11))CCMSH to facilitate its potential therapeutic application.

  19. Nicotine stimulates pancreatic cancer xenografts by systemic increase in stress neurotransmitters and suppression of the inhibitory neurotransmitter gamma-aminobutyric acid.

    Science.gov (United States)

    Al-Wadei, Hussein A N; Plummer, Howard K; Schuller, Hildegard M

    2009-03-01

    Pancreatic ductal adenocarcinoma (PDAC) is a leading cause of cancer mortality in Western countries. We have shown previously that four representative human PDAC cell lines were regulated by beta-adrenoreceptors via cyclic adenosine 3',5'-monophosphate (cAMP)-dependent signaling. In the current study, we have tested the hypothesis that nicotine stimulates the growth of PDAC xenografts in nude mice by increasing the systemic levels of the stress neurotransmitters adrenaline and noradrenaline, which are the physiological agonists for beta-adrenoreceptors and that inhibition by gamma-aminobutyric acid (GABA) of the adenylyl cyclase-dependent pathway downstream of adrenoreceptors blocks this effect. The size of xenografts from PDAC cell line Panc-1 was determined 30 days after inoculation of the cancer cells. Stress neurotransmitters in serum as well as cAMP in the cellular fraction of blood and in tumor tissue were assessed by immunoassays. Levels of GABA, its synthesizing enzymes GAD65 and GAD67 and beta-adrenergic signaling proteins in the tumor tissue were determined by western blotting. Nicotine significantly increased the systemic levels of adrenaline, noradrenaline and cAMP while increasing xenograft size and protein levels of cAMP, cyclic AMP response element-binding protein and p-extracellular signal-regulated kinase 1/2 in the tumor tissue. Nicotine additionally reduced the protein levels of both GAD isozymes and GABA in tumor tissue. Treatment with GABA abolished these responses to nicotine and blocked the development of xenografts in mice not exposed to nicotine. These findings suggest that the development and progression of PDAC is subject to significant modulation by stimulatory stress neurotransmitters and inhibitory GABA and that treatment with GABA may be useful for marker-guided cancer intervention of PDAC.

  20. The preparation and application of N-terminal 57 amino acid protein of the follicle-stimulating hormone receptor as a candidate male contraceptive vaccine

    Directory of Open Access Journals (Sweden)

    Cheng Xu

    2014-08-01

    Full Text Available Follicle-stimulating hormone receptor (FSHR, which is expressed only on Sertoli cells and plays a key role in spermatogenesis, has been paid attention for its potential in male contraception vaccine research and development. This study introduces a method for the preparation and purification of human FSHR 57-amino acid protein (FSHR-57aa as well as determination of its immunogenicity and antifertility effect. A recombinant pET-28a(+-FSHR-57aa plasmid was constructed and expressed in Escherichia coli strain BL21 Star TM (DE3 and the FSHR-57aa protein was separated and collected by cutting the gel and recovering activity by efficient refolding dialysis. The protein was identified by Western blot and high-performance liquid chromatography analysis with a band of nearly 7 kDa and a purity of 97.4%. Male monkeys were immunized with rhFSHR-57aa protein and a gradual rising of specific serum IgG antibody was found which reached a plateau on day 112 (16 weeks after the first immunization. After mating of one male with three female monkeys, the pregnancy rate of those mated with males immunized against FSHR-57aa was significantly decreased while the serum hormone levels of testosterone and estradiol were not disturbed in the control or the FSHR-57aa groups. By evaluating pathological changes in testicular histology, we found that the blood-testis barrier remained intact, in spite of some small damage to Sertoli cells. In conclusion, our study demonstrates that the rhFSHR-57aa protein might be a feasible male contraceptive which could affect sperm production without disturbing hormone levels.

  1. The effect of temperature on the stability of compounds used as UV-MALDI-MS matrix: 2,5-dihydroxybenzoic acid, 2,4,6-trihydroxyacetophenone, alpha-cyano-4-hydroxycinnamic acid, 3,5-dimethoxy-4-hydroxycinnamic acid, nor-harmane and harmane.

    Science.gov (United States)

    Tarzi, Olga I; Nonami, Hiroshi; Erra-Balsells, Rosa

    2009-02-01

    The thermal stability of several commonly used crystalline matrix-assisted ultraviolet laser desorption/ionization mass spectrometry (UV-MALDI-MS) matrices, 2,5-dihydroxybenzoic acid (gentisic acid; GA), 2,4,6-trihydroxyacetophenone (THA), alpha-cyano-4-hydroxycinnamic acid (CHC), 3,5-dimethoxy-4-hydroxycinnamic acid (sinapinic acid; SA), 9H-pirido[3,4-b]indole (nor-harmane; nor-Ho), 1-methyl-9H-pirido[3,4-b]indole (harmane; Ho), perchlorate of nor-harmanonium ([nor-Ho+H]+) and perchlorate of harmanonium ([Ho+H]+) was studied by heating them at their melting point and characterizing the remaining material by using different MS techniques [electron ionization mass spectrometry (EI-MS), ultraviolet laserdesorption/ionization-time-of-flight-mass spectrometry (UV-LDI-TOF-MS) and electrospray ionization-time-of-flight-mass spectrometry (ESI-TOF-MS)] as well as by thin layer chromatography analysis (TLC), electronic spectroscopy (UV-absorption, fluorescence emission and excitation spectroscopy) and 1H nuclear magnetic resonance spectroscopy (1H-NMR). In general, all compounds, except for CHC and SA, remained unchanged after fusion. CHC showed loss of CO2, yielding the trans-/cis-4-hydroxyphenylacrilonitrile mixture. This mixture was unambiguously characterized by MS and 1H-NMR spectroscopy, and its sublimation capability was demonstrated. These results explain the well-known cluster formation, fading (vanishing) and further recovering of CHC when used as a matrix in UV-MALDI-MS. Commercial SA (SA 98%; trans-SA/cis-SA 5:1) showed mainly cis- to-trans thermal isomerization and, with very poor yield, loss of CO2, yielding (3',5'-dimethoxy-4'-hydroxyphenyl)-1-ethene as the decarboxilated product. These thermal conversions would not drastically affect its behavior as a UV-MALDI matrix as happens in the case of CHC. Complementary studies of the photochemical stability of these matrices in solid state were also conducted. Copyright (c) 2008 John Wiley & Sons, Ltd.

  2. Comparison of cellular effects of starch-coated SPIONs and poly(lactic-co-glycolic acid matrix nanoparticles on human monocytes

    Directory of Open Access Journals (Sweden)

    Gonnissen D

    2016-10-01

    Full Text Available Dominik Gonnissen,1 Ying Qu,1,2 Klaus Langer,3 Cengiz Öztürk,4 Yuliang Zhao,2 Chunying Chen,2 Guiscard Seebohm,5 Martina Düfer,6 Harald Fuchs,1 Hans-Joachim Galla,7 Kristina Riehemann11Center for Nanotechnology, Institute of Physics, University of Münster, Münster, Germany; 2National Center for Nanoscience and Technology, Chinese Academy of Sciences, Beijing, People’s Republic of China; 3Institute of Pharmaceutical Technology and Biopharmacy, University of Münster, Münster, 4chemicell GmbH, Berlin, 5Department of Cardiovascular Medicine, Institute for Genetics of Heart Diseases, University Hospital Münster, 6Department of Pharmacology, Institute of Pharmaceutical and Medicinal Chemistry, 7Department of Cell Biology/Biophysics, Institute of Biochemistry, University of Münster, Münster, GermanyAbstract: Within the last years, progress has been made in the knowledge of the properties of medically used nanoparticles and their toxic effects, but still, little is known about their influence on cellular processes of immune cells. The aim of our comparative study was to present the influence of two different nanoparticle types on subcellular processes of primary monocytes and the leukemic monocyte cell line MM6. We used core-shell starch-coated superparamagnetic iron oxide nanoparticles (SPIONs and matrix poly(lactic-co-glycolic acid (PLGA nanoparticles for our experiments. In addition to typical biocompatibility testing like the detection of necrosis or secretion of interleukins (ILs, we investigated the impact of these nanoparticles on the actin cytoskeleton and the two voltage-gated potassium channels Kv1.3 and Kv7.1. Induction of necrosis was not seen for PLGA nanoparticles and SPIONs in primary monocytes and MM6 cells. Likewise, no alteration in secretion of IL-1β and IL-10 was detected under the same experimental conditions. In contrast, IL-6 secretion was exclusively downregulated in primary monocytes after contact with both

  3. Matrix inequalities

    CERN Document Server

    Zhan, Xingzhi

    2002-01-01

    The main purpose of this monograph is to report on recent developments in the field of matrix inequalities, with emphasis on useful techniques and ingenious ideas. Among other results this book contains the affirmative solutions of eight conjectures. Many theorems unify or sharpen previous inequalities. The author's aim is to streamline the ideas in the literature. The book can be read by research workers, graduate students and advanced undergraduates.

  4. Identification of Fatty Acids, Phospholipids, and Their Oxidation Products Using Matrix-Assisted Laser Desorption Ionization Mass Spectrometry and Electrospray Ionization Mass Spectrometry

    Science.gov (United States)

    Harmon, Christopher W.; Mang, Stephen A.; Greaves, John; Finlayson-Pitts, Barbara J.

    2010-01-01

    Electrospray ionization mass spectrometry (ESI-MS) and matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) have found increasing application in the analysis of biological samples. Using these techniques to solve problems in analytical chemistry should be an essential component of the training of undergraduate chemists. We…

  5. STIMULATION OF REDUCTIVE DECHLORINATION OF TETRA- CHLOROETHENE (PCE) IN ANAEROBIC AQUIFER MICROCOSMS BY ADDITION OF SHORT-CHAIN ORGANIC ACIDS OR ALCOHOLS

    Science.gov (United States)

    The effect of the addition of common fermentation products on the dehalogenation of tetrachloroethene was studied in methanogenic slurries made with aquifer solids. Lactate, propionate, crotonate, butyrate, and ethanol stimulated dehalogenation activity, while acetate, methanol, ...

  6. growth stimulant

    African Journals Online (AJOL)

    Effects of timing and duration of supplementation of LIVFIT VET ® (growth stimulant) as substitute for fish meal on the growth performance, haematology and clinical enzymes concentration of growing pigs.

  7. Determination of phenolic acids and flavonoids in raw propolis by silica-supported ionic liquid-based matrix solid phase dispersion extraction high performance liquid chromatography-diode array detection.

    Science.gov (United States)

    Wang, Zhibing; Sun, Rui; Wang, Yuanpeng; Li, Na; Lei, Lei; Yang, Xiao; Yu, Aimin; Qiu, Fangping; Zhang, Hanqi

    2014-10-15

    The silica-supported ionic liquid (S-SIL) was prepared by impregnation and used as the dispersion adsorbent of matrix solid phase dispersion (MSPD) for the simultaneous extraction of eight phenolic acids and flavonoids, including caffeic acid, ferulic acid, morin, luteolin, quercetin, apigenin, chrysin, and kaempferide in raw propolis. High performance liquid chromatography with a Zorbax SB-C18 column (150mm×4.6mm, 3.5μm) was used for separation of the analytes. The mobile phase consisted of 0.2% phosphoric acid aqueous solution and acetonitrile and the flow rate of the mobile phase was 0.5mL/min. The experimental conditions for silica-supported ionic liquid-based matrix solid phase dispersion (S-SIL-based MSPD) were optimized. S-SIL containing 10% [C6MIM]Cl was used as dispersant, 20mL of n-hexane as washing solvent and 15mL of methanol as elution solvent. The ratio of S-SIL to sample was selected to be 4:1. The standard curves showed good linear relationship (r>0.9995). The limits of detection and quantification were in the range of 5.8-22.2ngmL(-1) and 19.2-74.0ngmL(-1), respectively. The relative standard deviations (RSDs) of intra-day and inter-day determination were lower than 8.80% and 11.19%, respectively. The recoveries were between 65.51% and 92.32% with RSDs lower than 8.95%. Compared with ultrasound-assisted extraction (UAE) and soxhlet extraction, the present method consumed less sample, organic solvent, and extraction time, although the extraction yields obtained by S-SIL-based MSPD are slightly lower than those obtained by UAE. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Stimulation of d- and l-lactate dehydrogenases transcriptional levels in presence of diammonium hydrogen phosphate resulting to enhanced lactic acid production by Lactobacillus strain.

    Science.gov (United States)

    Singhvi, Mamata; Zendo, Takeshi; Iida, Hiroshi; Gokhale, Digambar; Sonomoto, Kenji

    2017-12-01

    The present study revealed the effect of nitrogen sources on lactic acid production and stimulation of d- and l-lactate dehydrogenases (LDH) of parent Lactobacillus lactis NCIM 2368 and its mutant RM2-24 generated after UV mutagenesis. Both the parent and mutant strains were evaluated for d-lactic acid production in control and modified media. The modified media did not show remarkable effect on lactic acid production in case of parent whereas mutant exhibited significant enhancement in d-lactic acid production along with the appearance of l-lactic acid in the broth. Both LDH activities and specific activities were found to be higher in mutant than the parent strain. These results suggested that the diammonium hydrogen phosphate in modified media triggered the expression of LDH genes leading to enhanced lactic acid production. This observation has been proved by studying the expression levels of d- and l-LDH genes of parent and mutant in control and modified media using quantitative RT-PCR technique. In case of mutant, the transcriptional levels of d-LDH and l-LDH increased ∼17 fold and ∼1.38 fold respectively in modified medium compared to the values obtained with control medium. In case of parent, no significant change in transcriptional levels of d- and l-LDH was found when the cells were grown in either control medium or modified medium. This study suggested that the mutant, RM2-24 has l-LDH gene which is expressed in presence of (NH 4 ) 2 HPO 4 resulting in l-lactic acid production. Co-production of l-lactic acid in d-lactic acid fermentation may be detrimental in the PLA production. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  9. Matrix analysis

    CERN Document Server

    Bhatia, Rajendra

    1997-01-01

    A good part of matrix theory is functional analytic in spirit. This statement can be turned around. There are many problems in operator theory, where most of the complexities and subtleties are present in the finite-dimensional case. My purpose in writing this book is to present a systematic treatment of methods that are useful in the study of such problems. This book is intended for use as a text for upper division and gradu­ ate courses. Courses based on parts of the material have been given by me at the Indian Statistical Institute and at the University of Toronto (in collaboration with Chandler Davis). The book should also be useful as a reference for research workers in linear algebra, operator theory, mathe­ matical physics and numerical analysis. A possible subtitle of this book could be Matrix Inequalities. A reader who works through the book should expect to become proficient in the art of deriving such inequalities. Other authors have compared this art to that of cutting diamonds. One first has to...

  10. New strategy for the determination of gliadins in maize- or rice-based foods matrix-assisted laser desorption/ionization time-of-flight mass spectrometry: fractionation of gliadins from maize or rice prolamins by acidic treatment.

    Science.gov (United States)

    Hernando, Alberto; Valdes, Israel; Méndez, Enrique

    2003-08-01

    A procedure for determining small quantities of gliadins by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) in gluten-free foods containing relatively large amounts of prolamin proteins from maize or rice is described. We report for the first time that gliadins, the ethanol-soluble wheat prolamin fraction, can be quantitatively solubilized in 1.0 M acetic acid, while the corresponding ethanol-soluble maize or rice prolamin fraction remains insoluble in acetic acid. We describe a methodology for the detection of gliadins in maize and rice foods based on a two-step procedure of extraction (60% aqueous ethanol followed by 1 M acetic acid). Subsequent MALDI-TOFMS analysis of the resulting acidic extract from these gluten-free foods clearly confirms the presence of a typical mass pattern corresponding to gliadin components, ranging from 30 to 45 kDa. Depending on the percentages of maize or rice flours employed in the elaboration of these foods, the combined procedure enables levels of gliadins from 100 to 400 ppm to be detected. The efficiency of this combined procedure corroborates enzyme-linked immunosorbent assay data for a large number of maize/rice gluten-free foods by means of direct visualization of the characteristic gliadin mass pattern in maize or rice foods. Copyright 2003 John Wiley & Sons, Ltd.

  11. Swelling of rat hepatocytes stimulates glycogen synthesis

    NARCIS (Netherlands)

    Baquet, A.; Hue, L.; Meijer, A. J.; van Woerkom, G. M.; Plomp, P. J.

    1990-01-01

    In hepatocytes from fasted rats, several amino acids are known to stimulate glycogen synthesis via activation of glycogen synthase. The hypothesis that an increase in cell volume resulting from amino acid uptake may be involved in the stimulation of glycogen synthesis is supported by the following

  12. Matrix pentagons

    Science.gov (United States)

    Belitsky, A. V.

    2017-10-01

    The Operator Product Expansion for null polygonal Wilson loop in planar maximally supersymmetric Yang-Mills theory runs systematically in terms of multi-particle pentagon transitions which encode the physics of excitations propagating on the color flux tube ending on the sides of the four-dimensional contour. Their dynamics was unraveled in the past several years and culminated in a complete description of pentagons as an exact function of the 't Hooft coupling. In this paper we provide a solution for the last building block in this program, the SU(4) matrix structure arising from internal symmetry indices of scalars and fermions. This is achieved by a recursive solution of the Mirror and Watson equations obeyed by the so-called singlet pentagons and fixing the form of the twisted component in their tensor decomposition. The non-singlet, or charged, pentagons are deduced from these by a limiting procedure.

  13. Matrix pentagons

    Directory of Open Access Journals (Sweden)

    A.V. Belitsky

    2017-10-01

    Full Text Available The Operator Product Expansion for null polygonal Wilson loop in planar maximally supersymmetric Yang–Mills theory runs systematically in terms of multi-particle pentagon transitions which encode the physics of excitations propagating on the color flux tube ending on the sides of the four-dimensional contour. Their dynamics was unraveled in the past several years and culminated in a complete description of pentagons as an exact function of the 't Hooft coupling. In this paper we provide a solution for the last building block in this program, the SU(4 matrix structure arising from internal symmetry indices of scalars and fermions. This is achieved by a recursive solution of the Mirror and Watson equations obeyed by the so-called singlet pentagons and fixing the form of the twisted component in their tensor decomposition. The non-singlet, or charged, pentagons are deduced from these by a limiting procedure.

  14. Invasive ability of human renal cell carcinoma cell line Caki-2 is accelerated by gamma-aminobutyric acid, via sustained activation of ERK1/2 inducible matrix metalloproteinases.

    Science.gov (United States)

    Inamoto, Teruo; Azuma, Haruhito; Sakamoto, Takeshi; Kiyama, Satoshi; Ubai, Takanobu; Kotake, Yatsugu; Watanabe, Masahito; Katsuoka, Yoji

    2007-10-01

    Gamma-aminobutyric acid (GABA) was first discovered as an inhibitory neurotransmitter in the central nervous system (CNS) and has been reported to have a variety of functions, including regulation of cell division, cell differentiation and maturation, and to be involved in the development of certain cancers outside the CNS. In the present study, using the human renal cell carcinoma cell line Caki-2, we demonstrated that GABA stimulation significantly increased the expression of MMP-2 and -9 and subsequently increased the invasive activity of the cancer cells. Because MAPK signaling is one of the key regulators of MMP expression, we further evaluated MAPK signaling after stimulation with GABA. It was found that GABA stimulation promoted the phosphorylation of MAPKs, including ERK1/2, JNK, and p38. ERK1/2 phosphorylation was sustained for up to 12 h, while phosphorylation of JNK and p38 returned to the endogenous level by 30 min. It was noteworthy that the ras/raf/MEK/ERK pathway inhibitor PD98059 attenuated GABA-induced MMP-9 expression and that both PD98059 and MMP inhibitors attenuated the GABA-induced invasive activity of Caki-2 cells. Moreover, data obtained by depletion of the MEK/ERK pathway using interfering RNA transfection of Caki-2 cells clearly corroborated the above results, as both MMP-9 expression and GABA-induced invasive ability were decreased significantly. We also demonstrated that the GABA-induced increase in invasive ability via ERK1/2 up-regulation was mediated mainly through the GABA-B receptor. These results indicate that GABA stimulation promotes cancer cell invasion and that the effect is partly due to ERK1/2-dependent up-regulation of MMPs.

  15. Short-Chain Fatty Acids Stimulate Angiopoietin-Like 4 Synthesis in Human Colon Adenocarcinoma Cells by Activating Peroxisome Proliferator-Activated Receptor γ

    DEFF Research Database (Denmark)

    Alex, Sheril; Lange, Katja; Amolo, Tom

    2013-01-01

    with the notion that fermentation leads to PPAR activation in vivo, feeding mice a diet rich in inulin induced PPAR target genes and pathways in the colon. We conclude that (i) SCFA potently stimulate ANGPTL4 synthesis in human colon adenocarcinoma cells and (ii) SCFA transactivate and bind to PPARγ. Our data...

  16. Biosynthesis of the Essential Fatty Acid Oxidation Cofactor Carnitine Is Stimulated in Heart and Liver after a Single Bout of Exercise in Mice

    Directory of Open Access Journals (Sweden)

    Tom L. Broderick

    2018-01-01

    Full Text Available We determined whether one single bout of exercise stimulates carnitine biosynthesis and carnitine uptake in liver and heart. Free carnitine (FC in plasma was assayed using acetyltransferase and [14C]acetyl-CoA in Swiss Webster mice after 1 hour of moderate-intensity treadmill running or 4 hours and 8 hours into recovery. Liver and heart were removed under the same conditions for measurement of carnitine biosynthesis enzymes (liver butyrobetaine hydroxylase, γ-BBH; heart trimethyllysine dioxygenase, TMLD, organic cation transporter-2 (OCTN2, carnitine transporter, and liver peroxisome proliferator-activated receptor-alpha (PPARα, transcription factor for γ-BBH and OCTN2 synthesis. In exercised mice, FC levels in plasma decreased while heart and liver OCTN2 protein expressed increased, reflecting active uptake of FC. During recovery, the rise in FC to control levels was associated with increased liver γ-BBH expression. Protein expression of PPARα was stimulated in liver after exercise and during recovery. Interestingly, heart TMLD protein was also detected after exercise. Acute exercise stimulates carnitine uptake in liver and heart. The rapid return of FC levels in plasma after exercise indicates carnitine biosynthesis by liver is stimulated to establish carnitine homeostasis. Our results suggest that exercise may benefit patients with carnitine deficiency syndromes.

  17. Titanium dioxide (TiO2) nanoparticles filled poly(d,l lactid acid) (PDLLA) matrix composites for bone tissue engineering

    NARCIS (Netherlands)

    Gerhardt, L.C.; Jell, G.M.R.; Boccaccini, A.R.

    2007-01-01

    Titanium dioxide (TiO2) nanoparticles were investigated for bone tissue engineering applications with regard to bioactivity and particle cytotoxicity. Composite films on the basis of poly(d,l lactid acid) (PDLLA) filled with 0, 5 and 30 wt% TiO2 nanoparticles were processed by solvent casting.

  18. Selective extraction of U(VI) over Th(IV) from acidic streams using di-bis(2-ethylhexyl) malonamide anchored chloromethylated polymeric matrix

    Energy Technology Data Exchange (ETDEWEB)

    Prabhakaran, D.; Subramanian, M.S. [Department of Chemistry, Indian Institute of Technology, Chennai 600036 (India)

    2005-01-15

    A new chelating polymeric sorbent has been developed using Merrifield chloromethylated resin anchored with di-bis (2-ethylhexyl) malonamide (DB2EHM). The modified resin was characterized by {sup 13}C CPMAS NMR spectroscopy, FT-NIR-FIR spectroscopy, CHN elemental analysis and also by thermo gravimetric analysis. The fabricated sorbent showed superior binding affinity for U(VI) over Th(IV) and other diverse ions, even under high acidities. Various physio-chemical parameters, like solution acidity, phase exchange kinetics, metal sorption capacity, electrolyte tolerance studies, etc., influencing the resin's metal extractive behavior were studied by both static and dynamic method. Batch extraction studies performed over a wide range of solution acidity (0.01-10M) revealed that selective extraction of U(VI) could be achieved even up to 4M acidity with distribution ratios (D) in the order of circa 10{sup 3}. The phase exchange kinetics studies performed for U(VI) and Th(IV) revealed that time duration of <15min was sufficient for >99.5% extraction. But similar studies when preformed for trivalent lanthanides gave very low D values (<50), with the extraction time extending up to 60min. The metal sorption studies performed for U(VI) and Th(IV) at 5M HNO{sub 3} was found to be 62.5 and 38.2mgg{sup -1},respectively. Extraction efficiency in the presence of inferring electrolyte species and inorganic cations were also examined. Metal ion desorption was effective using 10-15mL of 1M (NH{sub 4}){sub 2}CO{sub 3} or 0.5M {alpha}-hydroxy isobutyric acid (HIBA). Extraction studies performed on a chromatographic column at 5M acidity were found to give enrichment factor values of 310 and 250 for U(VI) and Th(IV), respectively. The practical utility of the fabricated chelating sorbent and its efficiency to extract actinides from acidic waste streams was tested using a synthetic nuclear spent fuel solution. The R.S.D. values obtained on triplicate measurements (n = 3) were within

  19. COMPOSITION OF FOWLPOX VIRUS AND INCLUSION MATRIX.

    Science.gov (United States)

    RANDALL, C C; GAFFORD, L G; DARLINGTON, R W; HYDE, J

    1964-04-01

    Randall, Charles C. (University of Mississippi School of Medicine, Jackson), Lanelle G. Gafford, Robert W. Darlington, and James M. Hyde. Composition of fowlpox virus and inclusion matrix. J. Bacteriol. 87:939-944. 1964.-Inclusion bodies of fowlpox virus infection are especially favorable starting material for the isolation of virus and inclusion matrix. Electron micrographs of viral particles and matrix indicated a high degree of purification. Density-gradient centrifugation of virus in cesium chloride and potassium tartrate was unsatisfactory because of inactivation, and clumping or disintegration. Chemical analyses of virus and matrix revealed significant amounts of lipid, protein, and deoxyribonucleic acid, but no ribonucleic acid or carbohydrate. Approximately 47% of the weight of the virus and 83% of the matrix were extractable in chloroform-methanol. The lipid partitions of the petroleum ether extracts were similar, except that the phospholipid content of the matrix was 2.2 times that of the virus. Viral particles were sensitive to diethyl ether and chloroform.

  20. Composite glycerol/graphite/aromatic acid matrices for thin-layer chromatography/matrix-assisted laser desorption/ionization mass spectrometry of heterocyclic compounds.

    Science.gov (United States)

    Esparza, Cesar; Borisov, R S; Varlamov, A V; Zaikin, V G

    2016-10-28

    New composite matrices have been suggested for the analysis of mixtures of different synthetic organic compounds (N-containing heterocycles and erectile dysfunction drugs) by thin layer chromatography/matrix-assisted laser desorption ionization time-of-flight mass spectrometry (TLC/MALDI-TOF). Different mixtures of classical MALDI matrices and graphite particles dispersed in glycerol were used for the registration of MALDI mass spectra directly from TLC plates after analytes separation. In most of cases, the mass spectra possessed [M+H] + ions; however, for some analytes only [M+Na] + and [M+K] + ions were observed. These ions have been used to generate visualized TLC chromatograms. The described approach increases the desorption/ionization efficiencies of analytes separated by TLC, prevent spot blurring, simplifies and decrease time for sample preparation. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Brain Stimulation Therapies

    Science.gov (United States)

    ... Magnetic Seizure Therapy Deep Brain Stimulation Additional Resources Brain Stimulation Therapies Overview Brain stimulation therapies can play ... for a shorter recovery time than ECT Deep Brain Stimulation Deep brain stimulation (DBS) was first developed ...

  2. Evaluating the efficacy of a structure-derived amino acid substitution matrix in detecting protein homologs by BLAST and PSI-BLAST.

    Science.gov (United States)

    Goonesekere, Nalin Cw

    2009-01-01

    The large numbers of protein sequences generated by whole genome sequencing projects require rapid and accurate methods of annotation. The detection of homology through computational sequence analysis is a powerful tool in determining the complex evolutionary and functional relationships that exist between proteins. Homology search algorithms employ amino acid substitution matrices to detect similarity between proteins sequences. The substitution matrices in common use today are constructed using sequences aligned without reference to protein structure. Here we present amino acid substitution matrices constructed from the alignment of a large number of protein domain structures from the structural classification of proteins (SCOP) database. We show that when incorporated into the homology search algorithms BLAST and PSI-blast, the structure-based substitution matrices enhance the efficacy of detecting remote homologs.

  3. Evaluating the efficacy of a structure-derived amino acid substitution matrix in detecting protein homologs by BLAST and PSI-BLAST

    OpenAIRE

    Goonesekere, Nalin CW

    2009-01-01

    Nalin CW GoonesekereDepartment of Chemistry and Biochemistry, University of Northern iowa, Cedar Falls, IA, USAAbstract: The large numbers of protein sequences generated by whole genome sequencing projects require rapid and accurate methods of annotation. The detection of homology through computational sequence analysis is a powerful tool in determining the complex evolutionary and functional relationships that exist between proteins. Homology search algorithms employ amino acid substitution ...

  4. Oxidizing gel formulation for nuclear decontamination: rheological and acidic properties of the organic matrix and its ozonolysis; Formulation d'un gel oxydant a matrice organique applicable a la decontamination nucleaire: proprietes rheologiques, acido-basiques et ozonolyse de la matrice

    Energy Technology Data Exchange (ETDEWEB)

    Rouy, E

    2003-10-15

    An acidic and oxidizing gel was formulated with a purely organic matrix, xanthan gum, at low concentrations (1 to 2 wt %). This polymer gel was investigated in various media (aqueous, acidic and ceric) by means of rheology: shear thinning behaviour, thixotropy, yield stress... Evidences of unexpected rheological properties in highly concentrated media show that xanthan is quite convenient for industrial projection of this type of gel on metallic walls in nuclear plants, notwithstanding its time-limited resistance to oxidation (about a few hours). Complexation mechanisms between ceric species and polar sites of the polymer led us to characterise acidic properties of our xanthan sample by potentiometric titration and {sup 1}H NMR techniques. The matrix was finally treated by ozonolysis to suppress organic residues, as required to handle nuclear wastes. In acidic medium, ozonolysis of the gel was achieved successfully while in acidic and ceric medium this process showed limited efficiency, needing further investigation to be clarified. (author)

  5. Oxidizing gel formulation for nuclear decontamination: rheological and acidic properties of the organic matrix and its ozonolysis; Formulation d'un gel oxydant a matrice organique applicable a la decontamination nucleaire: proprietes rheologiques, acido-basiques et ozonolyse de la matrice

    Energy Technology Data Exchange (ETDEWEB)

    Rouy, E

    2003-10-15

    An acidic and oxidizing gel was formulated with a purely organic matrix, xanthan gum, at low concentrations (1 to 2 wt %). This polymer gel was investigated in various media (aqueous, acidic and ceric) by means of rheology: shear thinning behaviour, thixotropy, yield stress... Evidences of unexpected rheological properties in highly concentrated media show that xanthan is quite convenient for industrial projection of this type of gel on metallic walls in nuclear plants, notwithstanding its time-limited resistance to oxidation (about a few hours). Complexation mechanisms between ceric species and polar sites of the polymer led us to characterise acidic properties of our xanthan sample by potentiometric titration and {sup 1}H NMR techniques. The matrix was finally treated by ozonolysis to suppress organic residues, as required to handle nuclear wastes. In acidic medium, ozonolysis of the gel was achieved successfully while in acidic and ceric medium this process showed limited efficiency, needing further investigation to be clarified. (author)

  6. Amperometric sensor for ascorbic acid based on a glassy carbon electrode modified with gold-silver bimetallic nanotubes in a chitosan matrix

    International Nuclear Information System (INIS)

    Yang, Penghao; Gao, Xia; Wang, Lisha; Wu, Qi; Chen, Zhichun; Lin, Xianfu

    2014-01-01

    We report on an amperometric sensor for ascorbic acid (AA) that is based on highly dense gold-silver nanotubes in a chitosan film on a glassy carbon electrode. The nanotubes were synthesized by a poly(vinyl pyrrolidone)-mediated polyol method employing a replacement reaction with silver nanowires as templates, and were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction. Under the optimal conditions, the sensor exhibits good electrocatalytic activity towards the oxidation of AA, and this enables the determination of AA in the 5 μM to 2 mM concentration range, with a detection limit at 2 μM (at an S/N of 3). The response time is 2 s. The sensor displays good reproducibility, selectivity, sensitivity, and long-term stability. (author)

  7. Different effects of anthocyanins and phenolic acids from wild blueberry (Vaccinium angustifolium) on monocytes adhesion to endothelial cells in a TNF-α stimulated proinflammatory environment

    DEFF Research Database (Denmark)

    Del Bo', Cristian; Roursgaard, Martin; Porrini, Marisa

    2016-01-01

    Scope: Monocyte adhesion to the vascular endothelium is a crucial step in the early stagesof atherogenesis. This study aims to investigate the capacity of an anthocyanin (ACN) andphenolic acid (PA) rich fraction (RF) of a wild blueberry, single ACNs (cyanidin, malvidin,delphinidin) and related me...

  8. Repeated injections of piracetam improve spatial learning and increase the stimulation of inositol phospholipid hydrolysis by excitatory amino acids in aged rats

    NARCIS (Netherlands)

    Canonico, P. L.; Aronica, E.; Aleppo, G.; Casabona, G.; Copani, A.; Favit, A.; Nicoletti, F.; Scapagnini, U.

    1991-01-01

    Repeated injections of piracetam (400 mg/kg, i.p. once a day for 15 days) to 16-month old rats led to an improved performance on an 8-arm radial maze, used as a test for spatial learning. This effect was accompanied by a greater ability of excitatory amino acids (ibotenate and glutamate) to

  9. Evidence of phytohormones and phenolic acids variability in garden-waste-derived vermicompost leachate, a well-known plant growth stimulant

    Czech Academy of Sciences Publication Activity Database

    Aremu, A.O.; Stirk, W.A.; Kulkarni, M. G.; Tarkowská, Danuše; Turečková, Veronika; Grúz, Jiří; Šubrtová, Michaela; Pěnčík, Aleš; Novák, Ondřej; Doležal, Karel; Strnad, Miroslav; van Staden, J.

    2015-01-01

    Roč. 75, č. 2 (2015), s. 483-492 ISSN 0167-6903 R&D Projects: GA MŠk LK21306; GA ČR GA14-34792S; GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : Abscisic acid * Biostimulant * Brassinosteroids Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.333, year: 2015

  10. The effects of orbital spaceflight on bone histomorphometry and messenger ribonucleic acid levels for bone matrix proteins and skeletal signaling peptides in ovariectomized growing rats

    Science.gov (United States)

    Cavolina, J. M.; Evans, G. L.; Harris, S. A.; Zhang, M.; Westerlind, K. C.; Turner, R. T.

    1997-01-01

    A 14-day orbital spaceflight was performed using ovariectomized Fisher 344 rats to determine the combined effects of estrogen deficiency and near weightlessness on tibia radial bone growth and cancellous bone turnover. Twelve ovariectomized rats with established cancellous osteopenia were flown aboard the space shuttle Columbia (STS-62). Thirty ovariectomized rats were housed on earth as ground controls: 12 in animal enclosure modules, 12 in vivarium cages, and 6 killed the day of launch for baseline measurements. An additional 18 ovary-intact rats were housed in vivarium cages as ground controls: 8 rats were killed as baseline controls and the remaining 10 rats were killed 14 days later. Ovariectomy increased periosteal bone formation at the tibia-fibula synostosis; cancellous bone resorption and formation in the secondary spongiosa of the proximal tibial metaphysis; and messenger RNA (mRNA) levels for the prepro-alpha2(1) subunit of type 1 collagen, osteocalcin, transforming growth factor-beta, and insulin-like growth factor I in the contralateral proximal tibial metaphysis and for the collagen subunit in periosteum pooled from tibiae and femora and decreased cancellous bone area. Compared to ovariectomized weight-bearing rats, the flight group experienced decreases in periosteal bone formation, collagen subunit mRNA levels, and cancellous bone area. The flight rats had a small decrease in the cancellous mineral apposition rate, but no change in the calculated bone formation rate. Also, spaceflight had no effect on cancellous osteoblast and osteoclast perimeters or on mRNA levels for bone matrix proteins and signaling peptides. On the other hand, spaceflight resulted in an increase in bone resorption, as ascertained from the diminished retention of a preflight fluorochrome label. This latter finding suggests that osteoclast activity was increased. In a follow-up ground-based experiment, unilateral sciatic neurotomy of ovariectomized rats resulted in cancellous

  11. Delineation of Stenotrophomonas maltophilia isolates from cystic fibrosis patients by fatty acid methyl ester profiles and matrix-assisted laser desorption/ionization time-of-flight mass spectra using hierarchical cluster analysis and principal component analysis.

    Science.gov (United States)

    Vidigal, Pedrina Gonçalves; Mosel, Frank; Koehling, Hedda Luise; Mueller, Karl Dieter; Buer, Jan; Rath, Peter Michael; Steinmann, Joerg

    2014-12-01

    Stenotrophomonas maltophilia is an opportunist multidrug-resistant pathogen that causes a wide range of nosocomial infections. Various cystic fibrosis (CF) centres have reported an increasing prevalence of S. maltophilia colonization/infection among patients with this disease. The purpose of this study was to assess specific fingerprints of S. maltophilia isolates from CF patients (n = 71) by investigating fatty acid methyl esters (FAMEs) through gas chromatography (GC) and highly abundant proteins by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), and to compare them with isolates obtained from intensive care unit (ICU) patients (n = 20) and the environment (n = 11). Principal component analysis (PCA) of GC-FAME patterns did not reveal a clustering corresponding to distinct CF, ICU or environmental types. Based on the peak area index, it was observed that S. maltophilia isolates from CF patients produced significantly higher amounts of fatty acids in comparison with ICU patients and the environmental isolates. Hierarchical cluster analysis (HCA) based on the MALDI-TOF MS peak profiles of S. maltophilia revealed the presence of five large clusters, suggesting a high phenotypic diversity. Although HCA of MALDI-TOF mass spectra did not result in distinct clusters predominantly composed of CF isolates, PCA revealed the presence of a distinct cluster composed of S. maltophilia isolates from CF patients. Our data suggest that S. maltophilia colonizing CF patients tend to modify not only their fatty acid patterns but also their protein patterns as a response to adaptation in the unfavourable environment of the CF lung. © 2014 The Authors.

  12. Increased gamma-aminobutyric acid levels in mouse brain induce loss of righting reflex, but not immobility, in response to noxious stimulation.

    Science.gov (United States)

    Katayama, Sohtaro; Irifune, Masahiro; Kikuchi, Nobuhito; Takarada, Tohru; Shimizu, Yoshitaka; Endo, Chie; Takata, Takashi; Dohi, Toshihiro; Sato, Tomoaki; Kawahara, Michio

    2007-06-01

    The general anesthetic state comprises behavioral and perceptual components, including amnesia, unconsciousness, and immobility. gamma-Aminobutyric acidergic (GABAergic) inhibitory neurotransmission is an important target for anesthetic action at the in vitro cellular level. In vivo, however, the functional relevance of enhancing GABAergic neurotransmission in mediating essential components of the general anesthetic state is unknown. Gabaculine is a GABA-transaminase inhibitor that inhibits degradation of released GABA, and consequently increases endogenous GABA in the central nervous system. Here, we examined, behaviorally, the ability of increased GABA levels to produce components of the general anesthetic state. All drugs were administered systemically in adult male ddY mice. To assess the general anesthetic components, two end-points were used. One was loss of righting reflex (LORR; as a measure of unconsciousness); the other was loss of movement in response to tail-clamp stimulation (as a measure of immobility). Gabaculine induced LORR in a dose-dependent fashion with a 50% effective dose of 100 (75-134; 95% confidence limits) mg/kg. The behavioral and microdialysis studies revealed that the endogenous GABA-induced LORR occurred in a brain concentration-dependent manner. However, even larger doses of gabaculine (285-400 mg/kg) produced no loss of tail-clamp response. In contrast, all the tested volatile anesthetics concentration-dependently abolished both righting and tail-clamp response, supporting the evidence that volatile anesthetics act on a variety of molecular targets. These findings indicate that LORR is associated with enhanced GABAergic neurotransmission, but that immobility in response to noxious stimulation is not, suggesting that LORR and immobility are mediated through different neuronal pathways and/or regions in the central nervous system.

  13. RSAT matrix-clustering: dynamic exploration and redundancy reduction of transcription factor binding motif collections.

    Science.gov (United States)

    Castro-Mondragon, Jaime Abraham; Jaeger, Sébastien; Thieffry, Denis; Thomas-Chollier, Morgane; van Helden, Jacques

    2017-07-27

    Transcription factor (TF) databases contain multitudes of binding motifs (TFBMs) from various sources, from which non-redundant collections are derived by manual curation. The advent of high-throughput methods stimulated the production of novel collections with increasing numbers of motifs. Meta-databases, built by merging these collections, contain redundant versions, because available tools are not suited to automatically identify and explore biologically relevant clusters among thousands of motifs. Motif discovery from genome-scale data sets (e.g. ChIP-seq) also produces redundant motifs, hampering the interpretation of results. We present matrix-clustering, a versatile tool that clusters similar TFBMs into multiple trees, and automatically creates non-redundant TFBM collections. A feature unique to matrix-clustering is its dynamic visualisation of aligned TFBMs, and its capability to simultaneously treat multiple collections from various sources. We demonstrate that matrix-clustering considerably simplifies the interpretation of combined results from multiple motif discovery tools, and highlights biologically relevant variations of similar motifs. We also ran a large-scale application to cluster ∼11 000 motifs from 24 entire databases, showing that matrix-clustering correctly groups motifs belonging to the same TF families, and drastically reduced motif redundancy. matrix-clustering is integrated within the RSAT suite (http://rsat.eu/), accessible through a user-friendly web interface or command-line for its integration in pipelines. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  14. Molecular dynamics simulations of matrix assisted laser desorption ionization: Matrix-analyte interactions

    International Nuclear Information System (INIS)

    Nangia, Shivangi; Garrison, Barbara J.

    2011-01-01

    There is synergy between matrix assisted laser desorption ionization (MALDI) experiments and molecular dynamics (MD) simulations. To understand analyte ejection from the matrix, MD simulations have been employed. Prior calculations show that the ejected analyte molecules remain solvated by the matrix molecules in the ablated plume. In contrast, the experimental data show free analyte ions. The main idea of this work is that analyte molecule ejection may depend on the microscopic details of analyte interaction with the matrix. Intermolecular matrix-analyte interactions have been studied by focusing on 2,5-dihydroxybenzoic acid (DHB; matrix) and amino acids (AA; analyte) using Chemistry at HARvard Molecular Mechanics (CHARMM) force field. A series of AA molecules have been studied to analyze the DHB-AA interaction. A relative scale of AA molecule affinity towards DHB has been developed.

  15. Involvement of CD36 in Modulating the Decrease of NPY and AgRP Induced by Acute Palmitic Acid Stimulation in N1E-115 Cells

    Directory of Open Access Journals (Sweden)

    Yan Ma

    2017-06-01

    Full Text Available Central nervous system (CNS fatty acid sensing plays an important role in the regulation of food intake, and palmitic acid (PA is the most important long chain fatty acid (LCFA in the mammalian diet. To explore the effect of PA on central neuropeptide expression and the role of the cluster of the differentiation of 36 (CD36 in the process, N1E-115 cells were cultured with PA in the presence or absence of sulfosuccinimidyl-oleate (SSO, a CD36 inhibitor. Results showed that 10 μmol/L PA significantly reduced NPY and AgRP mRNA expression after 20 min of exposure, while the expression of CD36 was upregulated. The presence of SSO significantly attenuated the decrease of NPY and AgRP expression that was induced by PA alone, although no notable effect on PA- induced CD36 gene expression was observed. In conclusion, our study suggests the involvement of CD36 in the PA-induced decrease of NPY and AgRP in N1E-115 cells.

  16. A Single Amino Acid Change in the Marburg Virus Matrix Protein VP40 Provides a Replicative Advantage in a Species-Specific Manner

    Science.gov (United States)

    Koehler, Alexander; Kolesnikova, Larissa; Welzel, Ulla; Schudt, Gordian; Herwig, Astrid

    2015-01-01

    ABSTRACT Marburg virus (MARV) induces severe hemorrhagic fever in humans and nonhuman primates but only transient nonlethal disease in rodents. However, sequential passages of MARV in rodents boosts infection leading to lethal disease. Guinea pig-adapted MARV contains one mutation in the viral matrix protein VP40 at position 184 (VP40D184N). The contribution of the D184N mutation to the efficacy of replication in a new host is unknown. In the present study, we demonstrated that recombinant MARV containing the D184N mutation in VP40 [rMARVVP40(D184N)] grew to higher titers than wild-type recombinant MARV (rMARVWT) in guinea pig cells. Moreover, rMARVVP40(D184N) displayed higher infectivity in guinea pig cells. Comparative analysis of VP40 functions indicated that neither the interferon (IFN)-antagonistic function nor the membrane binding capabilities of VP40 were affected by the D184N mutation. However, the production of VP40-induced virus-like particles (VLPs) and the recruitment of other viral proteins to the budding site was improved by the D184N mutation in guinea pig cells, which resulted in the higher infectivity of VP40D184N-induced infectious VLPs (iVLPs) compared to that of VP40-induced iVLPs. In addition, the function of VP40 in suppressing viral RNA synthesis was influenced by the D184N mutation specifically in guinea pig cells, thus allowing greater rates of transcription and replication. Our results showed that the improved viral fitness of rMARVVP40(D184N) in guinea pig cells was due to the better viral assembly function of VP40D184N and its lower inhibitory effect on viral transcription and replication rather than modulation of the VP40-mediated suppression of IFN signaling. IMPORTANCE The increased virulence achieved by virus passaging in a new host was accompanied by mutations in the viral genome. Analyzing how these mutations affect the functions of viral proteins and the ability of the virus to grow within new host cells helps in the understanding

  17. Assisted inhibition effect of acetylcholinesterase with n-octylphosphonic acid and application in high sensitive detection of organophosphorous pesticides by matrix-assisted laser desorption/ionization Fourier transform mass spectrometry.

    Science.gov (United States)

    Cai, Tingting; Zhang, Li; Wang, Haoyang; Zhang, Jing; Guo, Yinlong

    2011-11-14

    A simple and practical approach to improve the sensitivity of acetylcholinesterase (AChE)-inhibited method has been developed for monitoring organophosphorous (OP) pesticide residues. In this work, matrix-assisted laser desorption/ionization Fourier transform mass spectrometry (MALDI-FTMS) was used to detect AChE activity. Due to its good salt-tolerance and low sample consumption, MALDI-FTMS facilitates rapid and high-throughput screening of OP pesticides. Here we describe a new method to obtain low detection limits via employing external reagents. Among candidate compounds, n-octylphosphonic acid (n-Octyl-PA) displays assistant effect to enhance AChE inhibition by OP pesticides. In presence of n-Octyl-PA, the percentages of AChE inhibition still kept correlation with OP pesticide concentrations. The detection limits were improved significantly even by 10(2)-10(3) folds in comparison with conventional enzyme-inhibited methods. Different detection limits of OP pesticides with different toxicities were as low as 0.005 μg L(-1) for high toxic pesticides and 0.05 μg L(-1) for low toxic pesticides. Besides, the reliability of results from this method to analyze cowpea samples had been demonstrated by liquid-chromatography tandem mass spectrometry (LC-MS/MS). The application of this commercial available assistant agent shows great promise to detect OP compounds in complicated biological matrix and broadens the mind for high sensitivity detection of OP pesticide residues in agricultural products. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Low nitrogen stress stimulating the indole-3-acetic acid biosynthesis of Serratia sp. ZM is vital for the survival of the bacterium and its plant growth-promoting characteristic.

    Science.gov (United States)

    Ouyang, Liming; Pei, Haiyan; Xu, Zhaohui

    2017-04-01

    Serratia sp. ZM is a plant growth-promoting (PGP) bacterial strain isolated from the rhizospheric soil of Populus euphratica in northwestern China. In this study, low nitrogen supply significantly stimulated the production of indole-3-acetic acid (IAA) in Serratia sp.ZM. The inoculation of the bacterium to wheat seedlings improved plant growth compared with the uninoculated group, and the stimulating effect was more prominent under low nitrogen stress. Inactivation of the predicted key gene in the IAA biosynthesis pathway impaired IAA production and significantly hampered mutant growth in poor medium. Furthermore, the IAA-deficient mutant lost the PGP effect under either normal or low nitrogen conditions in plant experiments. This study revealed the significant impact of environmental nitrogen levels on IAA production in the PGP strain and the vital effect of IAA on resistance physiology of both the bacterium and host plant. The characteristics of Serratia sp. ZM also indicated its application potential as a biofertilizer for plants, especially those suffering from poor nitrogen soil.

  19. Human osteoarthritic cartilage shows reduced in vivo expression of IL-4, a chondroprotective cytokine that differentially modulates IL-1β-stimulated production of chemokines and matrix-degrading enzymes in vitro.

    Directory of Open Access Journals (Sweden)

    Elisa Assirelli

    Full Text Available BACKGROUND: In osteoarthritis (OA, an inflammatory environment is responsible for the imbalance between the anabolic and catabolic activity of chondrocytes and, thus, for articular cartilage derangement. This study was aimed at providing further insight into the impairment of the anabolic cytokine IL-4 and its receptors in human OA cartilage, as well as the potential ability of IL-4 to antagonize the catabolic phenotype induced by IL-1β. METHODOLOGY/PRINCIPAL FINDINGS: The in vivo expression of IL-4 and IL-4 receptor subunits (IL-4R, IL-2Rγ, IL-13Rα1 was investigated on full thickness OA or normal knee cartilage. IL-4 expression was found to be significantly lower in OA, both in terms of the percentage of positive cells and the amount of signal per cell. IL-4 receptor type I and II were mostly expressed in mid-deep cartilage layers. No significant difference for each IL-4 receptor subunit was noted. IL-4 anti-inflammatory and anti-catabolic activity was assessed in vitro in the presence of IL-1β and/or IL-4 for 24 hours using differentiated high density primary OA chondrocyte also exhibiting the three IL-4 R subunits found in vivo. Chemokines, extracellular matrix degrading enzymes and their inhibitors were evaluated at mRNA (real time PCR and protein (ELISA or western blot levels. IL-4 did not affect IL-1β-induced mRNA expression of GRO-α/CXCL1, IL-8/CXCL8, ADAMTS-5, TIMP-1 or TIMP-3. Conversely, IL-4 significantly inhibited RANTES/CCL5, MIP-1α/CCL3, MIP-1β/CCL4, MMP-13 and ADAMTS-4. These results were confirmed at protein level for RANTES/CCL5 and MMP-13. CONCLUSIONS/SIGNIFICANCE: Our results indicate for the first time that OA cartilage has a significantly lower expression of IL-4. Furthermore, we found differences in the spectrum of biological effects of IL-4. The findings that IL-4 has the ability to hamper the IL-1β-induced release of both MMP-13 and CCL5/RANTES, both markers of OA chondrocytes, strongly indicates IL-4 as a

  20. Sunlight assisted synthesis of silver nanoparticles in zeolite matrix and study of its application on electrochemical detection of dopamine and uric acid in urine samples

    International Nuclear Information System (INIS)

    Meenakshi, S.; Devi, S.; Pandian, K.; Devendiran, R.; Selvaraj, M.

    2016-01-01

    Sunlight assisted reduction of silver ions were accomplished for the synthesis of silver nanoparticles incorporated within the mesoporous silicate framework of zeolite Y. The zeolite-Y and AgNP/Zeo-Y were characterized by field emission scanning electron microscopy, transmission electron microscopy, N 2 adsorption-desorption BET isotherm and X–ray diffraction techniques. The incorporation of silver nanoparticles within the porous framework was further confirmed by cyclic voltammetry and electrochemical impedance spectroscopy. An enhanced electrocatalytic oxidation of biologically important molecules like dopamine and uric acid using AgNP/Zeo-Y modified glassy carbon electrode has been developed. A simultaneous oxidation of DA and UA peaks were obtained at + 0.31 V and + 0.43 V (vs. Ag/AgCl) using AgNP/Zeo-Y/GCE under the optimum experimental condition. A well-resolved peak potential window (~ 120 mV) for the oxidation of both DA and UA were observed at AgNP/Zeo-Y/GCE system. The calibration curves for DA and UA were obtained within the dynamic linear range of 0.02 × 10 −6 to 0.18 × 10 −6 M (R 2 = 0.9899) and 0.05 × 10 −6 to 0.7 × 10 −6 M (R 2 = 0.9996) and the detection limits were found to be 1.6 × 10 −8 M and 2.51 × 10 −8 M by using differential pulse voltammetry (DPV) method. The proposed method was successfully applied for the determination of both DA and UA in human urine samples with a related standard deviation was < 3%, and n = 5 using the standard addition method. - Highlights: • Sunlight assisted synthesis of AgNP/Zeo-Y via ion exchange method. • Enhanced electrocatalytic peak current values for DA and UA with a well separated peak to peak position. • AgNP/Zeo-Y/GCE for the simultaneous detection of DA and UA by CV and DPV methods. • Detection limit was found to be 1.60 × 10 -8 M and 2.51 × 10 −8 M for DA and UA respectively. • DPV technique was effectively realistic to detect DA and UA in urine samples.

  1. Inhibition of post-traumatic septic proteolysis and ureagenesis and stimulation of hepatic acute-phase protein production by branched-chain amino acid TPN.

    Science.gov (United States)

    Chiarla, C; Siegel, J H; Kidd, S; Coleman, B; Mora, R; Tacchino, R; Placko, R; Gum, M; Wiles, C E; Belzberg, H

    1988-08-01

    Previous studies have shown that severe sepsis after major trauma results in the reprioritization of release of hepatic acute-phase proteins (APP). They suggest competition for leucine for nutritional utilization may be responsible. To test this hypothesis, a branched-chain enriched (46.6%) amino acid mixture (BCAA) was administered on a prospective randomized basis with standard TPN therapy to 16 septic post-trauma patients. After sepsis was diagnosed, a randomized therapy (control-TPN or BCAA-TPN) was given for 12 days, or until death occurred. Total calories and amino acid nitrogen (N) administered were not different in the two groups (t-test) and q 8 h (347 study periods) amino acid clearances, urinary urea nitrogen excretion, muscle proteolysis from 3-methyl-histidine (3-MH) excretion, and standard indices of sepsis severity and hepatic function were measured, as well as platelets (PLAT), leucocytes (WBC), albumin (ALB), and six acute-phase proteins: C-reactive protein (CRP), alpha-1-antitrypsin (A1TRIP), fibrinogen (FIBRIN), alpha-2-macroglobulin (AMACRO), ceruloplasmin (CERUL), and transferrin (TRANS). Using Scheffé analysis of all contrasts the data showed: BCAA resulted in a fall in 24-hour urea N excretion (24.0 to 20.0 gm/24 hr) and in proteolysis (138 to 126 gm/24 hr) (p less than 0.0001). Prestudy CRP levels were all elevated, but compared to control where APP reprioritization occurred, over the initial 10 days of therapy BCAA patients had a more rapid fall in CRP with a more rapid rise in FIBRIN, TRANS, CERUL, ALBUMIN, AMACRO, and A1TRIP (all p less than 0.0001) relative to CRP. Also, the sepsis-reduced clearances of glutamine and glutamate, alanine, and proline were increased (p less than 0.0001) during BCAA even though urea nitrogen production was reduced (p less than 0.0001). The increase in leucine clearance with BCAA-enriched TPN was positively correlated (r2 = 0.601; p less than 0.0001) with the increase in the sum of all APP and ALB and was

  2. Airborne signals from Trichoderma fungi stimulate iron uptake responses in roots resulting in priming of jasmonic acid-dependent defences in shoots of Arabidopsis thaliana and Solanum lycopersicum.

    Science.gov (United States)

    Martínez-Medina, Ainhoa; Van Wees, Saskia C M; Pieterse, Corné M J

    2017-11-01

    Root colonization by Trichoderma fungi can trigger induced systemic resistance (ISR). In Arabidopsis, Trichoderma-ISR relies on the transcription factor MYB72, which plays a dual role in the onset of ISR and the activation of Fe uptake responses. Volatile compounds (VCs) from rhizobacteria are important elicitors of MYB72 in Arabidopsis roots. Here, we investigated the mode of action of VCs from Trichoderma fungi in the onset of ISR and Fe uptake responses. VCs from Trichoderma asperellum and Trichoderma harzianum were applied in an in vitro split-plate system with Arabidopsis or tomato seedlings. Locally, Trichoderma-VCs triggered MYB72 expression and molecular, physiological and morphological Fe uptake mechanisms in Arabidopsis roots. In leaves, Trichoderma-VCs primed jasmonic acid-dependent defences, leading to an enhanced resistance against Botrytis cinerea. By using Arabidopsis micrografts of VCs-exposed rootstocks and non-exposed scions, we demonstrated that perception of Trichoderma-VCs by the roots leads to a systemic signal that primes shoots for enhanced defences. Trichoderma-VCs also elicited Fe deficiency responses and shoot immunity in tomato, suggesting that this phenomenon is expressed in different plant species. Our results indicate that Trichoderma-VCs trigger locally a readjustment of Fe homeostasis in roots, which links to systemic elicitation of ISR by priming of jasmonic acid-dependent defences. © 2017 John Wiley & Sons Ltd.

  3. Chemical stimulation in unconventional hydrocarbons extraction in the USA: a preliminary environmental risk assessment.

    Science.gov (United States)

    Sutra, Emilie; Spada, Matteo; Burgherr, Peter

    2016-04-01

    While the exploitation of unconventional resources recently shows an extensive development, the stimulation techniques in use in this domain arouse growing public concerns. Often in the shadow of the disputed hydraulic fracturing process, the matrix acidizing is however a complementary or alternative procedure to enhance the reservoir connectivity. Although acidizing processes are widespread within the traditional hydrocarbons sources exploration, the matrix acidizing does not appear to be commonly used in unconventional hydrocarbons formations due to their low permeability. Nonetheless, this process has been recently applied to the Monterey formation, a shale oil play in California. These stimulation fluids are composed by various chemicals, what represents a matter of concern for public as well as for authorities. As a consequence, a risk assessment implying an exposure and toxicity analysis is needed. Focusing on site surface accidents, e.g., leak of a chemical from a storage tank, we develop in this study concentration scenarios for different exposure pathways to estimate the potential environmental risk associated with the use of specific hazardous substances in the matrix acidizing process for unconventional hydrocarbon reservoirs in the USA. Primary, information about the usage of different hazardous substances have been collected in order to extract the most frequently used chemicals. Afterwards, a probabilistic estimation of the environmental risk associated with the use of these chemicals is carried out by comparing the Predicted Environmental Concentrations (PEC) distribution with the Predicted No Effect Concentrations (PNEC) value. The latter is collected from a literature review, whereas the PEC is estimated as probability distribution concentrations in different environmental compartments (e.g., soil) built upon various predefined accident scenarios. By applying a probabilistic methodology for the concentrations, the level at which the used chemicals

  4. Lactic Acid Bacteria Inducing a Weak Interleukin-12 and Tumor Necrosis Alpha Response in Human Dendritic Cells Inhibit Strongly Stimulating Lactic Acid Bacteria but Act Synergistically with Gram-Negative Bacteria

    DEFF Research Database (Denmark)

    Zeuthen, Louise Hjerrild; Christensen, Hanne Risager; Frøkiær, Hanne

    2006-01-01

    The development and maintenance of immune homeostasis indispensably depend on signals from the gut flora. Lactic acid bacteria (LAB), which are gram-positive (G+) organisms, are plausible significant players and have received much attention. Gram-negative (G-) commensals, such as members...

  5. Efficiency criterion for teleportation via channel matrix, measurement matrix and collapsed matrix

    Directory of Open Access Journals (Sweden)

    Xin-Wei Zha

    Full Text Available In this paper, three kinds of coefficient matrixes (channel matrix, measurement matrix, collapsed matrix associated with the pure state for teleportation are presented, the general relation among channel matrix, measurement matrix and collapsed matrix is obtained. In addition, a criterion for judging whether a state can be teleported successfully is given, depending on the relation between the number of parameter of an unknown state and the rank of the collapsed matrix. Keywords: Channel matrix, Measurement matrix, Collapsed matrix, Teleportation

  6. Angiotensin II type 2 receptor stimulation improves fatty acid ovarian uptake and hyperandrogenemia in an obese rat model of polycystic ovary syndrome.

    Science.gov (United States)

    Leblanc, Samuel; Battista, Marie-Claude; Noll, Christophe; Hallberg, Anders; Gallo-Payet, Nicole; Carpentier, André C; Vine, Donna F; Baillargeon, Jean-Patrice

    2014-09-01

    Polycystic ovary syndrome (PCOS) is mainly defined by hyperandrogenism but is also characterized by insulin resistance (IR). Studies showed that overexposure of nonadipose tissues to nonesterified fatty acids (NEFA) may explain both IR and hyperandrogenism. Recent studies indicate that treatment with an angiotensin II type 2 receptor (AT2R)-selective agonist improves diet-induced IR. We thus hypothesized that PCOS hyperandrogenism is triggered by ovarian NEFA overexposure and is improved after treatment with an AT2R agonist. Experiments were conducted in 12-week-old female JCR:LA-cp/cp rats, which are characterized by visceral obesity, IR, hyperandrogenism, and polycystic ovaries. Control JCR:LA +/? rats have a normal phenotype. Rats were treated for 8 days with saline or the selective AT2R agonist C21/M24 and then assessed for: 1) fasting testosterone, NEFA, and insulin levels; and 2) an iv 14(R,S)-[(18)F]fluoro-6-thia-heptadecanoic acid test to determine NEFA ovarian tissue uptake (Km). Compared with controls, saline-treated PCOS/cp rats displayed higher insulin (100 vs 5.6 μU/mL), testosterone (0.12 vs 0.04 nmol/L), NEFA (0.98 vs 0.48 mmol/L), and Km (20.7 vs 12.9 nmol/g·min) (all P < .0001). In PCOS/cp rats, C21/M24 did not significantly improve insulin or NEFA but normalized testosterone (P = .004) and Km (P = .009), which were strongly correlated together in all PCOS/cp rats (ρ = 0.74, P = .009). In conclusion, in an obese PCOS rat model, ovarian NEFA uptake and testosterone levels are strongly associated and are both significantly reduced after short-term C21/M24 therapy. These findings provide new information on the role of NEFA in PCOS hyperandrogenemia and suggest a potential role for AT2R agonists in the treatment of PCOS.

  7. ZmPUMP encodes a fully functional monocot plant uncoupling mitochondrial protein whose affinity to fatty acid is increased with the introduction of a His pair at the second matrix loop

    International Nuclear Information System (INIS)

    Favaro, Regiane Degan; Borecky, Jiri; Colombi, Debora; Maia, Ivan G.

    2006-01-01

    Uncoupling proteins (UCPs) are specialized mitochondrial transporter proteins that uncouple respiration from ATP synthesis. In this study, cDNA encoding maize uncoupling protein (ZmPUMP) was expressed in Escherichia coli and recombinant ZmPUMP reconstituted in liposomes. ZmPUMP activity was associated with a linoleic acid (LA)-mediated H + efflux with K m of 56.36 ± 0.27 μM and V max of 66.9 μmol H + min -1 (mg prot) -1 . LA-mediated H + fluxes were sensitive to ATP inhibition with K i of 2.61 ± 0.36 mM (at pH 7.2), a value similar to those for dicot UCPs. ZmPUMP was also used to investigate the importance of a histidine pair present in the second matrix loop of mammalian UCP1 and absent in plant UCPs. ZmPUMP with introduced His pair (Lys155His and Ala157His) displayed a 1.55-fold increase in LA-affinity while its activity remained unchanged. Our data indicate conserved properties of plant UCPs and suggest an enhancing but not essential role of the histidine pair in proton transport mechanism

  8. Extended biorthogonal matrix polynomials

    Directory of Open Access Journals (Sweden)

    Ayman Shehata

    2017-01-01

    Full Text Available The pair of biorthogonal matrix polynomials for commutative matrices were first introduced by Varma and Tasdelen in [22]. The main aim of this paper is to extend the properties of the pair of biorthogonal matrix polynomials of Varma and Tasdelen and certain generating matrix functions, finite series, some matrix recurrence relations, several important properties of matrix differential recurrence relations, biorthogonality relations and matrix differential equation for the pair of biorthogonal matrix polynomials J(A,B n (x, k and K(A,B n (x, k are discussed. For the matrix polynomials J(A,B n (x, k, various families of bilinear and bilateral generating matrix functions are constructed in the sequel.

  9. Matrix completion by deep matrix factorization.

    Science.gov (United States)

    Fan, Jicong; Cheng, Jieyu

    2018-02-01

    Conventional methods of matrix completion are linear methods that are not effective in handling data of nonlinear structures. Recently a few researchers attempted to incorporate nonlinear techniques into matrix completion but there still exists considerable limitations. In this paper, a novel method called deep matrix factorization (DMF) is proposed for nonlinear matrix completion. Different from conventional matrix completion methods that are based on linear latent variable models, DMF is on the basis of a nonlinear latent variable model. DMF is formulated as a deep-structure neural network, in which the inputs are the low-dimensional unknown latent variables and the outputs are the partially observed variables. In DMF, the inputs and the parameters of the multilayer neural network are simultaneously optimized to minimize the reconstruction errors for the observed entries. Then the missing entries can be readily recovered by propagating the latent variables to the output layer. DMF is compared with state-of-the-art methods of linear and nonlinear matrix completion in the tasks of toy matrix completion, image inpainting and collaborative filtering. The experimental results verify that DMF is able to provide higher matrix completion accuracy than existing methods do and DMF is applicable to large matrices. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Characterization of organic matrix extracted from fresh water pearls

    International Nuclear Information System (INIS)

    Ma Yufei; Gao Yonghua; Feng Qingling

    2011-01-01

    Aragonite pearl and vaterite pearl from cultured Hyriopsis cumingii in Zhuji (Zhejiang province, China) were chosen for the study. The matrix proteins were extracted using water and weak acid, and classified as water soluble matrix (WSM), acid soluble matrix (ASM) and acid insoluble matrix (AIM). The proteins from both pearls were characterized by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), X-ray diffraction (XRD) and Fourier transformation infrared spectra (FTIR). The results showed that, AIM of aragonite pearl and vaterite pearl had an ordered structure of α-helix. ASM conformations of these two pearls were different from each other. WSM differed the most between these two pearls. - Research Highlights: → We use a specific method for extracting matrix proteins from aragonite pearl and vaterite pearl respectively. → The matrix proteins are extracted by water and weak acid, and classified as water soluble matrix (WSM), acid soluble matrix (ASM) and acid insoluble matrix (AIM). → AIM of aragonite pearl and vaterite pearl have an ordered structure. ASM conformations of the two pearls are different from each other. WSM differ the most between these two pearls.

  11. Spectrophotometric determination of silicon in silumin matrix

    International Nuclear Information System (INIS)

    Samanta, Papu; Pandey, K.L.; Kumar, Pradeep; Bagchi, A.C.; Abdulla, K.K.

    2015-01-01

    In dispersion fuel, fissile material is dispersed in inert matrix. Aluminum-silicon-nickel (silumin) alloy is employed as inert matrix owing to its high thermal conductivity, high castability, high corrosion resistance. All these properties depend on the chemical composition and the structure of silumin. Silicon is stringent specification in silumin. A spectrophotometric method has been developed for the determination of silicon content in silumin matrix. Silumin matrix was fused with LiOH and subsequent dissolution in water along with few drops of conc. sulphuric acid. The molybodo-silicic formed by the addition of ammonium molybdate is reduced to molybdenum blue by ascorbic acid in the presence of antimony. The absorbance was measured at 810 nm. Aluminum and nickel were found to be non-interfering with the silicon determination. (author)

  12. Enhanced root growth in phosphate-starved Arabidopsis by stimulating de novo phospholipid biosynthesis through the overexpression of LYSOPHOSPHATIDIC ACID ACYLTRANSFERASE 2 (LPAT2).

    Science.gov (United States)

    Angkawijaya, Artik Elisa; Nguyen, Van Cam; Nakamura, Yuki

    2017-09-01

    Upon phosphate starvation, plants retard shoot growth but promote root development presumably to enhance phosphate assimilation from the ground. Membrane lipid remodelling is a metabolic adaptation that replaces membrane phospholipids by non-phosphorous galactolipids, thereby allowing plants to obtain scarce phosphate yet maintain the membrane structure. However, stoichiometry of this phospholipid-to-galactolipid conversion may not account for the massive demand of membrane lipids that enables active growth of roots under phosphate starvation, thereby suggesting the involvement of de novo phospholipid biosynthesis, which is not represented in the current model. We overexpressed an endoplasmic reticulum-localized lysophosphatidic acid acyltransferase, LPAT2, a key enzyme that catalyses the last step of de novo phospholipid biosynthesis. Two independent LPAT2 overexpression lines showed no visible phenotype under normal conditions but showed increased root length under phosphate starvation, with no effect on phosphate starvation response including marker gene expression, root hair development and anthocyanin accumulation. Accompanying membrane glycerolipid profiling of LPAT2-overexpressing plants revealed an increased content of major phospholipid classes and distinct responses to phosphate starvation between shoot and root. The findings propose a revised model of membrane lipid remodelling, in which de novo phospholipid biosynthesis mediated by LPAT2 contributes significantly to root development under phosphate starvation. © 2017 John Wiley & Sons Ltd.

  13. 3',5'-Cyclic diguanylic acid (c-di-GMP) inhibits basal and growth factor-stimulated human colon cancer cell proliferation

    International Nuclear Information System (INIS)

    Karaolis, David K.R.; Cheng, Kunrong; Lipsky, Michael; Elnabawi, Ahmed; Catalano, Jennifer; Hyodo, Mamoru; Hayakawa, Yoshihiro; Raufman, Jean-Pierre

    2005-01-01

    The novel cyclic dinucleotide, 3',5'-cyclic diguanylic acid, cGpGp (c-di-GMP), is a naturally occurring small molecule that regulates important signaling mechanisms in prokaryotes. Recently, we showed that c-di-GMP has 'drug-like' properties and that c-di-GMP treatment might be a useful antimicrobial approach to attenuate the virulence and pathogenesis of Staphylococcus aureus and prevent or treat infection. In the present communication, we report that c-di-GMP (≤50 μM) has striking properties regarding inhibition of cancer cell proliferation in vitro. c-di-GMP inhibits both basal and growth factor (acetylcholine and epidermal growth factor)-induced cell proliferation of human colon cancer (H508) cells. Toxicity studies revealed that exposure of normal rat kidney cells and human neuroblastoma cells to c-di-GMP at biologically relevant doses showed no lethal cytotoxicity. Cyclic dinucleotides, such as c-di-GMP, represent an attractive and novel 'drug-platform technology' that can be used not only to develop new antimicrobial agents, but also to develop novel therapeutic agents to prevent or treat cancer

  14. Distinct signaling pathways leading to the induction of human β-defensin 2 by stimulating an electrolyticaly-generated acid functional water and double strand RNA in oral epithelial cells.

    Science.gov (United States)

    Gojoubori, Takahiro; Nishio, Yukina; Asano, Masatake; Nishida, Tetsuya; Komiyama, Kazuo; Ito, Koichi

    2014-04-01

    Defensins, a major family of cationic antimicrobial peptides, play important roles in innate immunity. In the present study, we investigated whether double-stranded RNA (dsRNA), a by-product of RNA virus replication, can induce human β-defensins-2 (hBD-2) expression in oral epithelial cells (OECs). We also examined the hBD-2-inducible activity of acid-electrolyzed functional water (FW). The results indicated that both dsRNA- and FW-induced hBD-2 expression in OECs. The induction efficiency was much higher for FW than for dsRNA. FW-induced production of hBD-2 was clearly observed by immunofluorescence staining. A luciferase assay was performed with 1.2 kb of the 5'-untranslated region (5'-UTR) of the hBD-2 gene. The results indicated that the nuclear factor-kappa B (NF-κB)-binding site proximal to the translation initiation site was indispensable for dsRNA-stimulated hBD-2 expression, but not in the case of FW. Moreover, FW-stimulated hBD-2 expression did not depend on NF-κB activity; instead, FW inhibited NF-κB activity. Pretreatment of the cells with specific inhibitors against NF-κB further confirmed NF-κB-independent hBD-2 induction by FW. In analogy to the results for intestinal epithelial cells (IECs), the dsRNA signal, but not FW, was sensed by toll-like receptor 3 (TLR3) in OECs. These results suggested that hBD-2 expression induced by dsRNA and FW is regulated by distinct mechanisms in OECs.

  15. Receptor-mediated inhibition of adenylate cyclase and stimulation of arachidonic acid release in 3T3 fibroblasts. Selective susceptibility to islet-activating protein, pertussis toxin

    International Nuclear Information System (INIS)

    Murayama, T.; Ui, M.

    1985-01-01

    Thrombin exhibited diverse effects on mouse 3T3 fibroblasts. It (a) decreased cAMP in the cell suspension, (b) inhibited adenylate cyclase in the Lubrol-permeabilized cell suspension in a GTP-dependent manner, increased releases of (c) arachidonic acid and (d) inositol from the cell monolayer prelabeled with these labeled compounds, (e) increased 45 Ca 2+ uptake into the cell monolayer, and (f) increased 86 Rb + uptake into the cell monolayer in a ouabain-sensitive manner. Most of the effects were reproduced by bradykinin, platelet-activating factor, and angiotensin II. The receptors for these agonists are thus likely to be linked to three separate effector systems: the adenylate cyclase inhibition, the phosphoinositide breakdown leading to Ca 2+ mobilization and phospholipase A2 activation, and the Na,K-ATPase activation. Among the effects of these agonists, (a), (b), (c), and (e) were abolished, but (d) and (f) were not, by prior treatment of the cells with islet-activating protein (IAP), pertussis toxin, which ADP-ribosylates the Mr = 41,000 protein, the alpha-subunit of the inhibitory guanine nucleotide regulatory protein (Ni), thereby abolishing receptor-mediated inhibition of adenylate cyclase. The effects (a), (c), (d), and (e) of thrombin, but not (b), were mimicked by A23187, a calcium ionophore. The effects of A23187, in contrast to those of receptor agonists, were not affected by the treatment of cells with IAP. Thus, the IAP substrate, the alpha-subunit of Ni, or the protein alike, may play an additional role in signal transduction arising from the Ca 2+ -mobilizing receptors, probably mediating process(es) distal to phosphoinositide breakdown and proximal to Ca 2+ gating

  16. The Matrix Cookbook

    DEFF Research Database (Denmark)

    Petersen, Kaare Brandt; Pedersen, Michael Syskind

    Matrix identities, relations and approximations. A desktop reference for quick overview of mathematics of matrices.......Matrix identities, relations and approximations. A desktop reference for quick overview of mathematics of matrices....

  17. Carbonate fuel cell matrix

    Science.gov (United States)

    Farooque, Mohammad; Yuh, Chao-Yi

    1996-01-01

    A carbonate fuel cell matrix comprising support particles and crack attenuator particles which are made platelet in shape to increase the resistance of the matrix to through cracking. Also disclosed is a matrix having porous crack attenuator particles and a matrix whose crack attenuator particles have a thermal coefficient of expansion which is significantly different from that of the support particles, and a method of making platelet-shaped crack attenuator particles.

  18. Matrix with Prescribed Eigenvectors

    Science.gov (United States)

    Ahmad, Faiz

    2011-01-01

    It is a routine matter for undergraduates to find eigenvalues and eigenvectors of a given matrix. But the converse problem of finding a matrix with prescribed eigenvalues and eigenvectors is rarely discussed in elementary texts on linear algebra. This problem is related to the "spectral" decomposition of a matrix and has important technical…

  19. Triangularization of a Matrix

    Indian Academy of Sciences (India)

    Much of linear algebra is devoted to reducing a matrix (via similarity or unitary similarity) to another that has lots of zeros. The simplest such theorem is the Schur triangularization theorem. This says that every matrix is unitarily similar to an upper triangular matrix. Our aim here is to show that though it is very easy to prove it ...

  20. Role of Acetyl Salicylic Acid in Controlling the DOCA-Salt Induced Hypertension in Rats by Stimulating the Synthesis of r-Cortexin in the Kidney.

    Science.gov (United States)

    Maji, Uttam Kumar; Jana, Pradipta; Chatterjee, Mitali; Karmakar, Sanmay; Saha, Arup; Ghosh, Tamal Kanti

    2018-03-01

    Hypertension is a metabolic disease which is caused by vasoconstriction and that results into elevated blood pressure. A chronic hypertensive condition affects and even damages to various systems in the body. Presence of renal cortexin (r-cortexin), an antihypertensive protein, which is released from the kidney cortex controls the blood pressure. The effect of r-cortexin was mediated through nitric oxide (NO), a universal vasodilating agent. In our study, acetyl salicylic acid (aspirin), a well-known activator of the endothelial nitric oxide synthase (eNOS) induced r-cortexin synthesis. The hypertensive rat model was prepared by injecting deoxy corticosterone acetate (DOCA). Synthesis of r-cortexin was measured by the anti-r-cortexin antibody which was raised in adult white Wister albino rat model. NO level was determined by using methemoglobin method and later confirmed by chemiluminescence method. Change in blood pressure was determined indirectly by using NIBP monitoring system. Aspirin increased the r-cortexin expression from 64.36 ± 12.6 nM to 216.7 ± 21.31 nM in DOCA induced hypertensive rats. The mechanism was proved with the findings of increased level of NO from 0.4 to 1.9 µM. The DOCA induced blood pressure was also decreased from 139.39 ± 7.36 mm of Hg to 116.57 ± 6.89 mm of Hg in case of systolic blood pressure and in case of diastolic pressure from 110.41 ± 7 mm of Hg to 86.4 ± 2.76 mm of Hg that are quite approximate. So, from this study it has been found that aspirin induces the r-cortexin synthesis in kidney cortex through the activation of eNOS in DOCA induced hypertensive rats.

  1. Transforming growth factor-beta 1 stimulates synthesis of proteoglycan aggregates in calf articular cartilage organ cultures

    International Nuclear Information System (INIS)

    Morales, T.I.

    1991-01-01

    Previous work showed that transforming growth factor-beta 1 (TGF-beta 1), added alone to bovine cartilage organ cultures, stimulated [35S]sulfate incorporation into macromolecular material but did not investigate the fidelity of the stimulated system to maintain synthesis of cartilage-type proteoglycans. This paper provides evidence that chondrocytes synthesize the appropriate proteoglycan matrix under TGF-beta 1 stimulation: (1) there is a coordinated increase in hyaluronic acid and proteoglycan monomer synthesis, (2) link-stable proteoglycan aggregates are assembled, (3) the hybrid chondroitin sulfate/keratan sulfate monomeric species is synthesized, and (4) there is an increase in protein core synthesis. Some variation in glycosylation patterns was observed when proteoglycans synthesized under TGF-beta 1 stimulation were compared to those synthesized under basal conditions. Thus comparing TGF-beta 1 to basal samples respectively, the monomers were larger (Kav on Sepharose CL-2B = 0.29 vs 0.41), the chondroitin sulfate chains were longer by approximately 3.5 kDa, the percentage of total glycosaminoglycan in keratan sulfate increased slightly from approximately 4% (basal) to approximately 6%, and the unsulfated disaccharide decreased from 28% (basal) to 12%. All of these variations are in the direction of a more anionic proteoglycan. Since the ability of proteoglycans to confer resiliency to the cartilage matrix is directly related to their anionic nature, these changes would presumably have a beneficial effect on tissue function

  2. Long term influence of regular intake of high dose n-3 fatty acids on CD40-ligand, pregnancy-associated plasma protein A and matrix metalloproteinase-9 following acute myocardial infarction.

    Science.gov (United States)

    Aarsetøy, Hildegunn; Brügger-Andersen, Trygve; Hetland, Øyvind; Grundt, Heidi; Nilsen, Dennis W T

    2006-02-01

    Pregnancy-associated plasma protein A (PAPP-A) and matrix metalloproteinase 9 (MMP-9), both zinc-binding endopeptidases, are abundantly expressed in ruptured and eroded plaques in patients with acute coronary syndromes (ACS). The adhesion molecule CD-40 ligand (CD40L), expressed on activated platelets and T-lymphocytes, can activate metalloproteinases and thereby promote plaque-rupture. N-3 fatty acids, through their anti-inflammatory and anti-thrombotic properties, might reduce the levels of these proatherosclerotic markers and thereby the development of ACS. 300 patients were randomized on day 4 to 6 following an acute myocardial infarction (MI) to receive either 4 g of n-3 fatty acids or a similar daily dose of corn oil for at least one year. We compared levels of PAPP-A, MMP-9 and sCD-40 L at baseline and 12 months in each group, and also looked for inter-group changes. In the omega-3 group, the median level of PAPP-A rose from 0.47 mU/l to 0.56 mU/l (p < 0.001). In the same group, sCD-40 L decreased from a mean baseline value of 5.19 ng/ml to 2.45 ng/ml (p < 0.001) and MMP-9 decreased nonsignificantly from 360.50 ng/ml to 308.00 ng/ml. Corresponding values for the corn oil group were 0.54 mU/l to 0.59 mU/l for PAPP-A (p = 0.007), 5.27 ng/ml to 2.84 ng/ml for sCD-40 L (p < 0.001) and 430.00 ng/ml to 324.00 ng/ml for MMP-9 (p = ns), respectively. In conclusion; both interventions resulted in a significant rise in PAPP-A, a significant decrease in sCD40L and a non-significant decrease in MMP-9 after 12 months of treatment in MI survivors. No inter-group differences were noted.

  3. Determination of spatial distribution of melamine-cyanuric acid crystals in rat kidney tissue by histology and imaging matrix-assisted laser desorption/ionization quadrupole time-of-flight mass spectrometry.

    Science.gov (United States)

    Kim, Chae-Wook; Yun, Jun-Won; Bae, Il-Hong; Lee, Joon-Seok; Kang, Hyun-Jin; Joo, Kyung-Mi; Jeong, Hye-Jin; Chung, Jin-Ho; Park, Young-Ho; Lim, Kyung-Min

    2010-01-01

    After the outbreak of acute renal failure associated with melamine-contaminated pet food, many attempts have been made to uncover the mechanism underlying the renal toxicity caused by melamine and melamine-related compounds. Using rat models, we investigated the renal crystal formation following the ingestion of a melamine-cyanuric acid mixture (M+CA, 1:1) to gain insight into the M+CA-induced renal toxicity. M+CA did not induce toxicity in precision-cut kidney slices, suggesting that M+CA does not have a direct nephrotoxicity. On the contrary, oral administration of M+CA for 3 days induced nephrotoxicity as determined by increased serum blood urea nitrogen and creatinine, reduced creatinine clearance, and enlarged kidneys in the animals treated with 50 mg/kg M+CA (melamine, 25 mg/kg, and cyanuric acid, 25 mg/kg; 2 of 10 animals) and 100 mg/kg M+CA (9 of 9 animals). While urine crystals were found in all animals treated with M+CA (25-100 mg/kg), histological examination revealed that renal crystals could be observed only in the kidneys of animals showing signs of nephrotoxicity. Remarkably, at 50 mg/kg M+CA, crystals were observed mainly in the medulla region of the kidney, while at 100 mg/kg, crystals were disseminated throughout the cortex and medulla regions. To further investigate the crystal formation by M+CA, matrix-assisted laser desorption/ionization quadrupole time-of-flight (MALDI-Q-TOF) imaging mass spectrometry detecting melamine distribution through monitoring the product ion (m/z 85, M + H) from melamine (m/z 127, M + H) was developed to directly obtain the image of melamine distribution in the kidney. The distribution image of melamine in kidney tissue confirmed that dense points of melamine were located only in the medulla region at 50 mg/kg M+CA, while at 100 mg/kg, they were disseminated widely from the cortex to medulla. These results demonstrated that M+CA ingestion could lead to crystal formation in kidney tubules along the osmotic gradient and

  4. Concomitant monitoring of implant formation and drug release of in situ forming poly (lactide-co-glycolide acid) implants in a hydrogel matrix mimicking the subcutis using UV-vis imaging.

    Science.gov (United States)

    Sun, Yu; Jensen, Henrik; Petersen, Nickolaj J; Larsen, Susan W; Østergaard, Jesper

    2018-02-20

    For poly (lactide-co-glycolide acid) (PLGA)-based in situ forming implants, the rate of implant formation plays an important role in determining the overall drug release kinetics. Currently, in vitro techniques capable of characterizing the processes of drug release and implant formation at the same time are not available. A hydrogel-based in vitro experimental setup was recently developed requiring only microliter of formulation and forming a closed system potentially suitable for interfacing with various spectroscopic techniques. The aim of the present proof-of-concept study was to investigate the feasibility of concomitant UV imaging, Vis imaging and light microscopy for detailed characterization of the behavior of in situ forming PLGA implants in the hydrogel matrix mimicking the subcutis. The model compounds, piroxicam and α-lactalbumin were added to PLGA-1-methyl-2-pyrrolidinone and PLGA-triacetin solutions. Upon bringing the PLGA-solvent-compound pre-formulation in contact with the hydrogel, Vis imaging and light microscopy were applied to visualize the depot formation and UV imaging was used to quantify drug transport in the hydrogel. As compared to piroxicam, the α-lactalbumin invoked an acceleration of phase separation and an increase of implant size. α-Lactalbumin was released faster from the PLGA-1-methyl-2-pyrrolidinone system than the PLGA-triacetin system opposite to the piroxicam release pattern. A linear relationship between the rate of implant formation and initial compound release within the first 4h was established for the PLGA-NMP systems. This implies that phase separation may be one of the controlling factors in drug release. The rate of implant formation may be an important parameter for predicting and tailoring drug release. The approach combining UV imaging, Vis imaging and light microscopy may facilitate understanding of release processes and holds potential for becoming a useful tool in formulation development of in situ forming

  5. A Comparative Study of the Application of Fluorescence Excitation-Emission Matrices Combined with Parallel Factor Analysis and Nonnegative Matrix Factorization in the Analysis of Zn Complexation by Humic Acids

    Directory of Open Access Journals (Sweden)

    Patrycja Boguta

    2016-10-01

    Full Text Available The main aim of this study was the application of excitation-emission fluorescence matrices (EEMs combined with two decomposition methods: parallel factor analysis (PARAFAC and nonnegative matrix factorization (NMF to study the interaction mechanisms between humic acids (HAs and Zn(II over a wide concentration range (0–50 mg·dm−3. The influence of HA properties on Zn(II complexation was also investigated. Stability constants, quenching degree and complexation capacity were estimated for binding sites found in raw EEM, EEM-PARAFAC and EEM-NMF data using mathematical models. A combination of EEM fluorescence analysis with one of the proposed decomposition methods enabled separation of overlapping binding sites and yielded more accurate calculations of the binding parameters. PARAFAC and NMF processing allowed finding binding sites invisible in a few raw EEM datasets as well as finding totally new maxima attributed to structures of the lowest humification. Decomposed data showed an increase in Zn complexation with an increase in humification, aromaticity and molecular weight of HAs. EEM-PARAFAC analysis also revealed that the most stable compounds were formed by structures containing the highest amounts of nitrogen. The content of oxygen-functional groups did not influence the binding parameters, mainly due to fact of higher competition of metal cation with protons. EEM spectra coupled with NMF and especially PARAFAC processing gave more adequate assessments of interactions as compared to raw EEM data and should be especially recommended for modeling of complexation processes where the fluorescence intensities (FI changes are weak or where the processes are interfered with by the presence of other fluorophores.

  6. Insulin-like growth factor I has independent effects on bone matrix formation and cell replication

    International Nuclear Information System (INIS)

    Hock, J.M.; Centrella, M.; Canalis, E.

    1988-01-01

    The effects of insulin-like growth factor-I (IGF-I) and insulin on bone matrix synthesis and bone cell replication were studied in cultured 21-day-old fetal rat calvariae. Histomorphometry techniques were developed to measure the incorporation of [2,3- 3 H]proline and [methyl- 3 H]thymidine into bone matrix and bone cell nuclei, respectively, using autoradiographs of sagittal sections of calvariae cultured with IGF-I, insulin, or vehicle for up to 96 h. To confirm an effect on bone formation, IGF-I was also studied for its effects on [ 3 H]proline incorporation into collagenase-digestible protein (CDP) and noncollagen protein and on [ 3 H]thymidine incorporation into acid-precipitable material (DNA). IGF-I at 10(-9)-10(-7) M significantly increased the rate of bone matrix apposition and CDP after 24 h by 45-50% and increased cell labeling by 8-fold in the osteoprogenitor cell zone, by 4-fold in the osteoblast cell zone, and by 2-fold in the periosteal fibroblast zone. Insulin at 10(-9)-10(-6) M also increased matrix apposition rate and CDP by 40-50%, but increased cell labeling by 2-fold only at a concentration of 10(-7) M or higher and then only in the osteoprogenitor cell zone. When hydroxyurea was added to IGF-I-treated bones, the effects of IGF-I on DNA synthesis were abolished, but the increase in bone matrix apposition induced by IGF-I was only partly diminished. In conclusion, IGF-I stimulates matrix synthesis in calvariae, an effect that is partly, although not completely, dependent on its stimulatory effect on DNA synthesis

  7. Antiaging effects of a novel facial serum containing L-ascorbic acid, proteoglycans, and proteoglycan-stimulating tripeptide: ex vivo skin explant studies and in vivo clinical studies in women

    Directory of Open Access Journals (Sweden)

    Garre A

    2018-05-01

    Full Text Available Aurora Garre,1 Mridvika Narda,1 Palmira Valderas-Martinez,1 Jaime Piquero,2 Corinne Granger1 1Innovation and Development, ISDIN SA, Barcelona, Spain; 2Dermik Clinic, Barcelona, Spain Background: With age, decreasing dermal levels of proteoglycans, collagen, and elastin lead to the appearance of aged skin. Oxidation, largely driven by environmental factors, plays a central role.Aim: The aim of this study was to assess the antiaging efficacy of a topical serum containing l-ascorbic acid, soluble proteoglycans, low molecular weight hyaluronic acid, and a tripeptide in ex vivo and in vivo clinical studies.Methods: Photoaging and photo-oxidative damage were induced in human skin explants by artificial solar radiation. Markers of oxidative stress – reactive oxygen species (ROS, total glutathione (GSH, and cyclobutane pyrimidine dimers (CPDs – were measured in serum-treated explants and untreated controls. Chronological aging was simulated using hydrocortisone. In both ex vivo studies, collagen, elastin, and proteoglycans were determined as measures of dermal matrix degradation. In women aged 21–67 years, hydration was measured up to 24 hours after a single application of serum, using Corneometer and hygrometer. Subjects’ perceptions of efficacy and acceptability were assessed via questionnaire after once-daily serum application for 4 weeks. Studies were performed under the supervision of a dermatologist.Results: In the photoaging study, irradiation induced changes in ROS, CPD, GSH, collagen, and elastin levels; these changes were reversed by topical serum application. The serum also protected against hydrocortisone-induced reduction in collagen, elastin, and proteoglycan levels, which were significantly higher in the serum-treated group vs untreated hydrocortisone-control explants. In clinical studies, serum application significantly increased skin moisture for 6 hours. Healthy volunteers perceived the product as efficient in making the

  8. Binding of triiodothyronine to rat liver nuclear matrix. influence of thyroid hormones on the phosphorylation of nuclear matrix proteins

    International Nuclear Information System (INIS)

    Adylova, A.T.; Atakhanova, B.A.

    1986-01-01

    The interaction of thyroid hormones with rat liver nuclear matrix proteins was investigated. It was shown that the nuclear matrix contains sites that bind triiodothyronine with high affinity (K = 1.07.10 9 M -1 ) and limited capacity (the maximum binding capacity is equal to 28 /SUP a/ .5 fmoles of triiodothyronine per 100 ug protein). Electrophoretic identification of the matrix proteins that bind triiodothyronine was performed. The molecular weight of the main triiodothyronine-binding fraction is 50,000-52,000. It was shown that the administration of triiodothyronine to thyroidectomized rats stimulates the phosphorylation of all the protein fractions of the nuclear matrix

  9. Parallelism in matrix computations

    CERN Document Server

    Gallopoulos, Efstratios; Sameh, Ahmed H

    2016-01-01

    This book is primarily intended as a research monograph that could also be used in graduate courses for the design of parallel algorithms in matrix computations. It assumes general but not extensive knowledge of numerical linear algebra, parallel architectures, and parallel programming paradigms. The book consists of four parts: (I) Basics; (II) Dense and Special Matrix Computations; (III) Sparse Matrix Computations; and (IV) Matrix functions and characteristics. Part I deals with parallel programming paradigms and fundamental kernels, including reordering schemes for sparse matrices. Part II is devoted to dense matrix computations such as parallel algorithms for solving linear systems, linear least squares, the symmetric algebraic eigenvalue problem, and the singular-value decomposition. It also deals with the development of parallel algorithms for special linear systems such as banded ,Vandermonde ,Toeplitz ,and block Toeplitz systems. Part III addresses sparse matrix computations: (a) the development of pa...

  10. Neutrino mass matrix

    International Nuclear Information System (INIS)

    Strobel, E.L.

    1985-01-01

    Given the many conflicting experimental results, examination is made of the neutrino mass matrix in order to determine possible masses and mixings. It is assumed that the Dirac mass matrix for the electron, muon, and tau neutrinos is similar in form to those of the quarks and charged leptons, and that the smallness of the observed neutrino masses results from the Gell-Mann-Ramond-Slansky mechanism. Analysis of masses and mixings for the neutrinos is performed using general structures for the Majorana mass matrix. It is shown that if certain tentative experimental results concerning the neutrino masses and mixing angles are confirmed, significant limitations may be placed on the Majorana mass matrix. The most satisfactory simple assumption concerning the Majorana mass matrix is that it is approximately proportional to the Dirac mass matrix. A very recent experimental neutrino mass result and its implications are discussed. Some general properties of matrices with structure similar to the Dirac mass matrices are discussed

  11. Stimulation of DNA synthesis in cultured rat alveolar type II cells

    International Nuclear Information System (INIS)

    Leslie, C.C.; McCormick-Shannon, K.; Robinson, P.C.; Mason, R.J.

    1985-01-01

    Restoration of the alveolar epithelium after injury is thought to be dependent on the proliferation of alveolar type II cells. To understand the factors that may be involved in promoting type II cell proliferation in vivo, we determined the effect of potential mitogens and culture substrata on DNA synthesis in rat alveolar type II cells in primary culture. Type II cells cultured in basal medium containing 10% fetal bovine serum (FBS) exhibited essentially no DNA synthesis. Factors that stimulated 3 H-thymidine incorporation included cholera toxin, epidermal growth factor, and rat serum. The greatest degree of stimulation was achieved by plating type II cells on an extracellular matrix prepared from bovine corneal endothelial cells and then by culturing the pneumocytes in medium containing rat serum, cholera toxin, insulin, and epidermal growth factor. Under conditions of stimulation of 3 H-thymidine incorporation there was an increased DNA content per culture dish but no increase in cell number. The ability of various culture conditions to promote DNA synthesis in type II cells was verified by autoradiography. Type II cells were identified by the presence of cytoplasmic inclusions, which were visualized by tannic acid staining before autoradiography. These results demonstrate the importance of soluble factors and culture substratum in stimulating DNA synthesis in rat alveolar type II cells in primary culture

  12. Study of ionization process of matrix molecules in matrix-assisted laser desorption ionization

    Energy Technology Data Exchange (ETDEWEB)

    Murakami, Kazumasa; Sato, Asami; Hashimoto, Kenro; Fujino, Tatsuya, E-mail: fujino@tmu.ac.jp

    2013-06-20

    Highlights: ► Proton transfer and adduction reaction of matrix in MALDI were studied. ► Hydroxyl group forming intramolecular hydrogen bond was related to the ionization. ► Intramolecular proton transfer in the electronic excited state was the initial step. ► Non-volatile analytes stabilized protonated matrix in the ground state. ► A possible mechanism, “analyte support mechanism”, has been proposed. - Abstract: Proton transfer and adduction reaction of matrix molecules in matrix-assisted laser desorption ionization were studied. By using 2,4,6-trihydroxyacetophenone (THAP), 2,5-dihydroxybenzoic acid (DHBA), and their related compounds in which the position of a hydroxyl group is different, it was clarified that a hydroxyl group forming an intramolecular hydrogen bond is related to the ionization of matrix molecules. Intramolecular proton transfer in the electronic excited state of the matrix and subsequent proton adduction from a surrounding solvent to the charge-separated matrix are the initial steps for the ionization of matrix molecules. Nanosecond pump–probe NIR–UV mass spectrometry confirmed that the existence of analyte molecules having large dipole moment in their structures is necessary for the stabilization of [matrix + H]{sup +} in the electronic ground state.

  13. [Acetyl-11-keto-beta-boswellic acid and arsenic trioxide regulate the productions and activities of matrix metalloproteinases in human skin fibroblasts and human leukemia cell line THP-1].

    Science.gov (United States)

    Liang, Ya-hui; Li, Ping; Zhao, Jing-xia; Liu, Xin; Huang, Qi-fu

    2010-11-01

    In order to reveal the treatment mechanism of Chinese medicine with the effect of activating blood and resolving putridity, we selected acetyl-11-keto-beta-boswellic acid (AKBA) and arsenic trioxide (ATO), the main monomeric components of frankincense and arsenolite which are two most commonly used Chinese medicine with effect of activating blood and resolving putridity. We combined AKBA and ATO as a compound, and explored its regulatory role in productions and activities of matrix metalloproteinase (MMP)-1, MMP-2 and MMP-9 in human skin fibroblasts (HSFbs) and human acute monocytic leukemia cell line THP-1 in inflammatory state. In order to simulate the inflammatory micro-environment of chronic wounds, we established 3 cell models: HSFb model activated by tumor necrosis factor-alpha (TNF-α), THP-1 cell model activated by phorbol-12-myristate-13-acetate (PMA) and HSFb-THP-1 cell coculture system. AKBA and ATO were cocultured with these cell models. Enzyme-linked immunosorbent assay (ELISA), gelatin zymography assay and reverse transcription-polymerase chain reaction (RT-PCR) were used to test the secretions, activities and mRNA expressions of MMP-1, MMP-2 and MMP-9. In the study of the regulatory mechanism of AKBA and ATO on MMPs, AKBA and ATO were cocultured with the cell models. ELISA was used to test the secretions of TNF-α and interleukin-1beta (IL-β) and Western blot was used to test the phosphorylation levels of extracellular signal-regulated kinases 1 and 2 (ERK1/2) and p38 mitogen-activated proteinkinase (p38MAPK). Compound of AKBA and ATO inhibited MMP-1, MMP-2 and MMP-9 mRNA expressions, secretions and activities respectively in HSFbs and THP-1 cells in inflammatory state (PTHP-1 cells and cell coculture system (PTHP-1 cells (P<0.05, P<0.01). The combined use of AKBA and ATO which in line with the rule of activating blood and resolving putridity inhibits fibroblasts and inflammatory cells in producing MMPs in inflammatory state through inhibiting the

  14. Interpolation of rational matrix functions

    CERN Document Server

    Ball, Joseph A; Rodman, Leiba

    1990-01-01

    This book aims to present the theory of interpolation for rational matrix functions as a recently matured independent mathematical subject with its own problems, methods and applications. The authors decided to start working on this book during the regional CBMS conference in Lincoln, Nebraska organized by F. Gilfeather and D. Larson. The principal lecturer, J. William Helton, presented ten lectures on operator and systems theory and the interplay between them. The conference was very stimulating and helped us to decide that the time was ripe for a book on interpolation for matrix valued functions (both rational and non-rational). When the work started and the first partial draft of the book was ready it became clear that the topic is vast and that the rational case by itself with its applications is already enough material for an interesting book. In the process of writing the book, methods for the rational case were developed and refined. As a result we are now able to present the rational case as an indepe...

  15. Thermo-stimulated current and dielectric loss in composite materials

    International Nuclear Information System (INIS)

    Nishijima, S.; Hagihara, T.; Okada, T.

    1986-01-01

    Thermo-stimulated current and dielectric loss measurements have been performed on five kinds of commercially available composite materials in order to study the electric properties of composite materials at low temperatures. Thermo-stimulated current measurements have been made on the composite materials in which the matrix quality was changed intentionally. The changes in the matrices were introduced by gamma irradiation or different curing conditions. Thermo-stimulated current and dielectric loss measurements revealed the number and the molecular weight of dipolar molecules. The different features of thermo-stimulated current and dielectric losses were determined for different composite materials. The gamma irradiation and the curing conditions especially affect the thermo-stimulated current features. The changes in macroscopic mechanical properties reflect those of thermo-stimulated current. It was found that the change in quality and/or degradation of the composite materials could be detected by means of thermo-stimulated current and/or dielectric loss measurements

  16. Patience of matrix games

    DEFF Research Database (Denmark)

    Hansen, Kristoffer Arnsfelt; Ibsen-Jensen, Rasmus; Podolskii, Vladimir V.

    2013-01-01

    For matrix games we study how small nonzero probability must be used in optimal strategies. We show that for image win–lose–draw games (i.e. image matrix games) nonzero probabilities smaller than image are never needed. We also construct an explicit image win–lose game such that the unique optimal...

  17. Matrix comparison, Part 2

    DEFF Research Database (Denmark)

    Schneider, Jesper Wiborg; Borlund, Pia

    2007-01-01

    The present two-part article introduces matrix comparison as a formal means for evaluation purposes in informetric studies such as cocitation analysis. In the first part, the motivation behind introducing matrix comparison to informetric studies, as well as two important issues influencing such c...

  18. Unitarity of CKM Matrix

    CERN Document Server

    Saleem, M

    2002-01-01

    The Unitarity of the CKM matrix is examined in the light of the latest available accurate data. The analysis shows that a conclusive result cannot be derived at present. Only more precise data can determine whether the CKM matrix opens new vistas beyond the standard model or not.

  19. Characteristics of global organic matrix in normal and pimpled chicken eggshells.

    Science.gov (United States)

    Liu, Z; Song, L; Zhang, F; He, W; Linhardt, R J

    2017-10-01

    The organic matrix from normal and pimpled calcified chicken eggshells were dissociated into acid-insoluble, water-insoluble, and facultative-soluble (both acid- and water-soluble) components, to understand the influence of shell matrix on eggshell qualities. A linear correlation was shown among these 3 matrix components in normal eggshells but was not observed in pimpled eggshells. In pimpled eggshells, the percentage contents of all 4 groups of matrix (the total matrix, acid-insoluble matrix, water-insoluble matrix, and facultative-soluble matrix) were significantly higher than that in normal eggshells. The amounts of both total matrix and acid-insoluble matrix in individual pimpled calcified shells were high, even though their weight was much lower than a normal eggshell. In both normal and pimpled eggshells, the calcified eggshell weight and shell thickness significantly and positively correlated with the amounts of all 4 groups of matrix in an individual calcified shell. In normal eggshells, the calcified shell thickness and shell breaking strength showed no significant correlations with the percentage contents of all 4 groups of matrix. In normal eggshells, only the shell membrane weight significantly correlated with the constituent ratios of both acid-insoluble matrix and facultative-soluble matrix in the whole matrix. In pimpled eggshells, 3 variables (calcified shell weight, shell thickness, and breaking strength) were significantly correlated with the constituent proportions of both acid-insoluble matrix and facultative-matrix. This study suggests that mechanical properties of normal eggshells may not linearly depend on the organic matrix content in the calcified eggshells and that pimpled eggshells might result by the disequilibrium enrichment of some proteins with negative effects. © 2017 Poultry Science Association Inc.

  20. Fuzzy risk matrix

    International Nuclear Information System (INIS)

    Markowski, Adam S.; Mannan, M. Sam

    2008-01-01

    A risk matrix is a mechanism to characterize and rank process risks that are typically identified through one or more multifunctional reviews (e.g., process hazard analysis, audits, or incident investigation). This paper describes a procedure for developing a fuzzy risk matrix that may be used for emerging fuzzy logic applications in different safety analyses (e.g., LOPA). The fuzzification of frequency and severity of the consequences of the incident scenario are described which are basic inputs for fuzzy risk matrix. Subsequently using different design of risk matrix, fuzzy rules are established enabling the development of fuzzy risk matrices. Three types of fuzzy risk matrix have been developed (low-cost, standard, and high-cost), and using a distillation column case study, the effect of the design on final defuzzified risk index is demonstrated

  1. Fuzzy vulnerability matrix

    International Nuclear Information System (INIS)

    Baron, Jorge H.; Rivera, S.S.

    2000-01-01

    The so-called vulnerability matrix is used in the evaluation part of the probabilistic safety assessment for a nuclear power plant, during the containment event trees calculations. This matrix is established from what is knows as Numerical Categories for Engineering Judgement. This matrix is usually established with numerical values obtained with traditional arithmetic using the set theory. The representation of this matrix with fuzzy numbers is much more adequate, due to the fact that the Numerical Categories for Engineering Judgement are better represented with linguistic variables, such as 'highly probable', 'probable', 'impossible', etc. In the present paper a methodology to obtain a Fuzzy Vulnerability Matrix is presented, starting from the recommendations on the Numerical Categories for Engineering Judgement. (author)

  2. Beneficial Regulation of Matrix Metalloproteinases for Skin Health

    Directory of Open Access Journals (Sweden)

    Neena Philips

    2011-01-01

    Full Text Available Matrix metalloproteinases (MMPs are essential to the remodeling of the extracellular matrix. While their upregulation facilitates aging and cancer, they are essential to epidermal differentiation and the prevention of wound scars. The pharmaceutical industry is active in identifying products that inhibit MMPs to prevent or treat aging and cancer and products that stimulate MMPs to prevent epidermal hyperproliferative diseases and wound scars.

  3. Spinal cord stimulation

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/007560.htm Spinal cord stimulation To use the sharing features on this page, please enable JavaScript. Spinal cord stimulation is a treatment for pain that uses ...

  4. Feldspar, Infrared Stimulated Luminescence

    DEFF Research Database (Denmark)

    Jain, Mayank

    2014-01-01

    This entry primarily concerns the characteristics and the origins of infrared-stimulated luminescence in feldspars.......This entry primarily concerns the characteristics and the origins of infrared-stimulated luminescence in feldspars....

  5. Growth hormone stimulation test

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003377.htm Growth hormone stimulation test To use the sharing features on this page, please enable JavaScript. The growth hormone (GH) stimulation test measures the ability of ...

  6. Structural characterization of native high-methoxylated pectin using nuclear magnetic resonance spectroscopy and ultraviolet matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Comparative use of 2,5-dihydroxybenzoic acid and nor-harmane as UV-MALDI matrices.

    Science.gov (United States)

    Monge, María Eugenia; Negri, R Martín; Kolender, Adriana A; Erra-Balsells, Rosa

    2007-01-01

    The successful analysis by ultraviolet matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (UV-MALDI-TOF MS) of native and hydrolyzed high-methoxylated pectin samples is described. In order to find the optimal conditions for UV-MALDI-TOF MS analysis several experimental variables were studied such as: different UV-MALDI matrices (nor-harmane, 2,5-dihydroxybenzoic acid), sample preparation methods (mixture, sandwich), inorganic salt addition (doping salts, NaCl, KCl, NH(4)Cl), ion mode (positive, negative), linear and reflectron mode, etc. nor-Harmane has never been used as a UV-MALDI matrix for the analysis of pectins but its use avoids pre-treatment of the sample, such as an enzymatic digestion or an acid hydrolysis, and there is no need to add salts, making the analysis easier and faster. This study suggested an alternative way of analyzing native high-methoxylated pectins, with UV-MALDI-TOF MS, by using nor-harmane as the matrix in negative ion mode. The analysis by (1)H and (13)C nuclear magnetic resonance (NMR) spectroscopy of the native and hydrolyzed pectin is also briefly described. Copyright (c) 2007 John Wiley & Sons, Ltd.

  7. Reducing interaction in simultaneous paired stimulation with CI.

    Directory of Open Access Journals (Sweden)

    Dirk Vellinga

    Full Text Available In this study simultaneous paired stimulation of electrodes in cochlear implants is investigated by psychophysical experiments in 8 post-lingually deaf subjects (and one extra subject who only participated in part of the experiments. Simultaneous and sequential monopolar stimulation modes are used as references and are compared to channel interaction compensation, partial tripolar stimulation and a novel sequential stimulation strategy named phased array compensation. Psychophysical experiments are performed to investigate both the loudness integration during paired stimulation at the main electrodes as well as the interaction with the electrode contact located halfway between the stimulating pair. The study shows that simultaneous monopolar stimulation has more loudness integration on the main electrodes and more interaction in between the electrodes than sequential stimulation. Channel interaction compensation works to reduce the loudness integration at the main electrodes, but does not reduce the interaction in between the electrodes caused by paired stimulation. Partial tripolar stimulation uses much more current to reach the needed loudness, but shows the same interaction in between the electrodes as sequential monopolar stimulation. In phased array compensation we have used the individual impedance matrix of each subject to calculate the current needed on each electrode to exactly match the stimulation voltage along the array to that of sequential stimulation. The results show that the interaction in between the electrodes is the same as monopolar stimulation. The strategy uses less current than partial tripolar stimulation, but more than monopolar stimulation. In conclusion, the paper shows that paired stimulation is possible if the interaction is compensated.

  8. The nuclear reaction matrix

    International Nuclear Information System (INIS)

    Krenciglowa, E.M.; Kung, C.L.; Kuo, T.T.S.; Osnes, E.; and Department of Physics, State University of New York at Stony Brook, Stony Brook, New York 11794)

    1976-01-01

    Different definitions of the reaction matrix G appropriate to the calculation of nuclear structure are reviewed and discussed. Qualitative physical arguments are presented in support of a two-step calculation of the G-matrix for finite nuclei. In the first step the high-energy excitations are included using orthogonalized plane-wave intermediate states, and in the second step the low-energy excitations are added in, using harmonic oscillator intermediate states. Accurate calculations of G-matrix elements for nuclear structure calculations in the Aapprox. =18 region are performed following this procedure and treating the Pauli exclusion operator Q 2 /sub p/ by the method of Tsai and Kuo. The treatment of Q 2 /sub p/, the effect of the intermediate-state spectrum and the energy dependence of the reaction matrix are investigated in detail. The present matrix elements are compared with various matrix elements given in the literature. In particular, close agreement is obtained with the matrix elements calculated by Kuo and Brown using approximate methods

  9. Preferential binding of DNA primase to the nuclear matrix

    International Nuclear Information System (INIS)

    Wood, S.H.; Collins, J.M.

    1986-01-01

    Several lines of research have stimulated interest in the nuclear matrix as the subcellular site of DNA replication. The authors have recently reported a relationship between rates of DNA synthesis and the differential binding of polymerase α to the nuclear matrix. They now report the detection of DNA primase bound to the HeLa nuclear matrix. Matrix-bound primase can be measured either indirectly, by the incorporation of [ 32 P] dAMP into an unprimed single-stranded template, or directly, by the incorporation of [ 3 H] AMP into matrix DNA. Characteristics of this system include a requirement for ATP, inhibition by adenosine-5'-0-(3'-thiotriphosphate), a primase inhibitor, and insensitivity to aphidicolin and α-amanitine, inhibitors of polymerase α and RNA polymerase, respectively. Subcellular quantification of primase and polymerase α activity revealed that while a majority of primase activity is bound to the matrix (72%), only 32% of polymerase α activity is matrix-bound. Treatment of the nuclear matrix with β-D-Octylglucoside allowed the solubilization of 54% of primase activity and 39% of polymerase α activity. This data provides further evidence of a structural and functional role for the nuclear matrix in DNA replication. The ability to solubilize matrix-bound replicative enzymes may prove to be an important tool in the elucidation of the spatial organization of DNA replication

  10. Chondrocyte secreted CRTAC1: a glycosylated extracellular matrix molecule of human articular cartilage.

    Science.gov (United States)

    Steck, Eric; Bräun, Jessica; Pelttari, Karoliina; Kadel, Stephanie; Kalbacher, Hubert; Richter, Wiltrud

    2007-01-01

    Cartilage acidic protein 1 (CRTAC1), a novel human marker which allowed discrimination of human chondrocytes from osteoblasts and mesenchymal stem cells in culture was so far studied only on the RNA-level. We here describe its genomic organisation and detect a new brain expressed (CRTAC1-B) isoform resulting from alternate last exon usage which is highly conserved in vertebrates. In humans, we identify an exon sharing process with the neighbouring tail-to-tail orientated gene leading to CRTAC1-A. This isoform is produced by cultured human chondrocytes, localized in the extracellular matrix of articular cartilage and its secretion can be stimulated by BMP4. Of five putative O-glycosylation motifs in the last exon of CRTAC1-A, the most C-terminal one is modified according to exposure of serial C-terminal deletion mutants to the O-glycosylation inhibitor Benzyl-alpha-GalNAc. Both isoforms contain four FG-GAP repeat domains and an RGD integrin binding motif, suggesting cell-cell or cell-matrix interaction potential. In summary, CRTAC1 acquired an alternate last exon from the tail-to-tail oriented neighbouring gene in humans resulting in the glycosylated isoform CRTAC1-A which represents a new extracellular matrix molecule of articular cartilage.

  11. Matrix Metalloproteinase Enzyme Family

    Directory of Open Access Journals (Sweden)

    Ozlem Goruroglu Ozturk

    2013-04-01

    Full Text Available Matrix metalloproteinases play an important role in many biological processes such as embriogenesis, tissue remodeling, wound healing, and angiogenesis, and in some pathological conditions such as atherosclerosis, arthritis and cancer. Currently, 24 genes have been identified in humans that encode different groups of matrix metalloproteinase enzymes. This review discuss the members of the matrix metalloproteinase family and their substrate specificity, structure, function and the regulation of their enzyme activity by tissue inhibitors. [Archives Medical Review Journal 2013; 22(2.000: 209-220

  12. Matrix groups for undergraduates

    CERN Document Server

    Tapp, Kristopher

    2005-01-01

    Matrix groups touch an enormous spectrum of the mathematical arena. This textbook brings them into the undergraduate curriculum. It makes an excellent one-semester course for students familiar with linear and abstract algebra and prepares them for a graduate course on Lie groups. Matrix Groups for Undergraduates is concrete and example-driven, with geometric motivation and rigorous proofs. The story begins and ends with the rotations of a globe. In between, the author combines rigor and intuition to describe basic objects of Lie theory: Lie algebras, matrix exponentiation, Lie brackets, and maximal tori.

  13. Elementary matrix theory

    CERN Document Server

    Eves, Howard

    1980-01-01

    The usefulness of matrix theory as a tool in disciplines ranging from quantum mechanics to psychometrics is widely recognized, and courses in matrix theory are increasingly a standard part of the undergraduate curriculum.This outstanding text offers an unusual introduction to matrix theory at the undergraduate level. Unlike most texts dealing with the topic, which tend to remain on an abstract level, Dr. Eves' book employs a concrete elementary approach, avoiding abstraction until the final chapter. This practical method renders the text especially accessible to students of physics, engineeri

  14. EOR by stimulated microflora

    Energy Technology Data Exchange (ETDEWEB)

    Svarovskaya, L.I.; Altunina, L.K.; Rozhenkova, Z.A.; Bulavin, V.D. [Institute of Petroleum Chemistry, Tomsk (Russian Federation)

    1995-12-31

    A combined microbiological and physico-chemical method for EOR has been developed for flooded West Siberia oil fields with formation temperature of 45{degrees}-95{degrees}C (318-365K). Formation water includes rich and various biocenoses numbering up to 2 x 10{sup 7} cells per ml. Representatives of genera, i.e, Pseudomonas, Bacillus, Actinomyces, Micrococcus, Mycobacterium, Sarcina, etc. were found to be the most widely distributed microorganisms. The method is based on injection of systems exhibiting high oil displacing capacity and at the same time being an additional nitrous nutrient for endemic populations of microorganisms. Their injection into formation water favors biomass growth by 4-6 orders and promotes syntheses of biosurfactants, biopolymers, acids, etc., and gaseous products. The features of residual oil displacement have been studied on laboratory models using a combined microbiological and physico-chemical method. A curve for the yield of residual oil is presented by two peaks. The first peak is stipulated by the washing action of oil displacement system, and the second one by the effect of metabolites produced at stimulation of biogenic processes. Oil displacement index increases by 15%-30%.

  15. Pseudomonas biofilm matrix composition and niche biology

    Science.gov (United States)

    Mann, Ethan E.; Wozniak, Daniel J.

    2014-01-01

    Biofilms are a predominant form of growth for bacteria in the environment and in the clinic. Critical for biofilm development are adherence, proliferation, and dispersion phases. Each of these stages includes reinforcement by, or modulation of, the extracellular matrix. Pseudomonas aeruginosa has been a model organism for the study of biofilm formation. Additionally, other Pseudomonas species utilize biofilm formation during plant colonization and environmental persistence. Pseudomonads produce several biofilm matrix molecules, including polysaccharides, nucleic acids, and proteins. Accessory matrix components shown to aid biofilm formation and adaptability under varying conditions are also produced by pseudomonads. Adaptation facilitated by biofilm formation allows for selection of genetic variants with unique and distinguishable colony morphology. Examples include rugose small-colony variants and wrinkly spreaders (WS), which over produce Psl/Pel or cellulose, respectively, and mucoid bacteria that over produce alginate. The well-documented emergence of these variants suggests that pseudomonads take advantage of matrix-building subpopulations conferring specific benefits for the entire population. This review will focus on various polysaccharides as well as additional Pseudomonas biofilm matrix components. Discussions will center on structure–function relationships, regulation, and the role of individual matrix molecules in niche biology. PMID:22212072

  16. Hacking the Matrix.

    Science.gov (United States)

    Czerwinski, Michael; Spence, Jason R

    2017-01-05

    Recently in Nature, Gjorevski et al. (2016) describe a fully defined synthetic hydrogel that mimics the extracellular matrix to support in vitro growth of intestinal stem cells and organoids. The hydrogel allows exquisite control over the chemical and physical in vitro niche and enables identification of regulatory properties of the matrix. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. The Matrix Organization Revisited

    DEFF Research Database (Denmark)

    Gattiker, Urs E.; Ulhøi, John Parm

    1999-01-01

    This paper gives a short overview of matrix structure and technology management. It outlines some of the characteristics and also points out that many organizations may actualy be hybrids (i.e. mix several ways of organizing to allocate resorces effectively).......This paper gives a short overview of matrix structure and technology management. It outlines some of the characteristics and also points out that many organizations may actualy be hybrids (i.e. mix several ways of organizing to allocate resorces effectively)....

  18. Bioprocessing of wheat bran in whole wheat bread increases the bioavailability of phenolic acids in men and exerts antiinflammatory effects ex vivo.

    Science.gov (United States)

    Mateo Anson, Nuria; Aura, Anna-Marja; Selinheimo, Emilia; Mattila, Ismo; Poutanen, Kaisa; van den Berg, Robin; Havenaar, Robert; Bast, Aalt; Haenen, Guido R M M

    2011-01-01

    Whole grain consumption has been linked to a lower risk of metabolic syndrome, which is normally associated with a low-grade chronic inflammation. The benefits of whole grain are in part related to the inclusion of the bran, rich in phenolic acids and fiber. However, the phenols are poorly bioaccessible from the cereal matrix. The aim of the present study was to investigate the effect of bioprocessing of the bran in whole wheat bread on the bioavailability of phenolic acids, the postprandial plasma antioxidant capacity, and ex vivo antiinflammatory properties. After consumption of a low phenolic acid diet for 3 d and overnight fasting, 8 healthy men consumed 300 g of whole wheat bread containing native bran (control bread) or bioprocessed bran (bioprocessed bread) in a cross-over design. Urine and blood samples were collected for 24 h to analyze the phenolic acids and metabolites. Trolox equivalent antioxidant capacity was measured in plasma. Cytokines were measured in blood after ex vivo stimulation with LPS. The bioavailabilities of ferulic acid, vanillic acid, sinapic acid, and 3,4-dimethoxybenzoic acid from the bioprocessed bread were 2- to 3-fold those from the control bread. Phenylpropionic acid and 3-hydroxyphenylpropionic acid were the main colonic metabolites of the nonbioaccessible phenols. The ratios of pro-:antiinflammatory cytokines were significantly lower in LPS-stimulated blood after the consumption of the bioprocessed bread. In conclusion, bioprocessing can remarkably increase the bioavailability of phenolic acids and their circulating metabolites, compounds which have immunomodulatory effects ex vivo.

  19. Localization of an O-glycosylated site in the recombinant barley alpha-amylase 1 produced in yeast and correction of the amino acid sequence using matrix-assisted laser desorption/ionization mass spectrometry of peptide mixtures

    DEFF Research Database (Denmark)

    Andersen, Jens S.; Søgaard, M; Svensson, B

    1994-01-01

    Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) of peptide mixtures was used to characterize recombinant barley alpha-amylase 1, produced in yeast. Three peptide mixtures were generated by cleavage with CNBr, digestion with endoproteinase Lys-C and Asp-N, respectively...

  20. Post irradiative stimulation of the lipids synthesis in the cells of Anacystis nidulans

    International Nuclear Information System (INIS)

    Groshev, V.V.; Tiflova, O.A.

    1982-01-01

    Ultraviolet and X-ray irradiations stimulate postradiation synthesis of fatty acids of lipids in cells of Anacystis nidulans. Stimulation degree is proportional to the radiation dose and time of postradiation incubation of cells

  1. Matrix Information Geometry

    CERN Document Server

    Bhatia, Rajendra

    2013-01-01

    This book is an outcome of the Indo-French Workshop on Matrix Information Geometries (MIG): Applications in Sensor and Cognitive Systems Engineering, which was held in Ecole Polytechnique and Thales Research and Technology Center, Palaiseau, France, in February 23-25, 2011. The workshop was generously funded by the Indo-French Centre for the Promotion of Advanced Research (IFCPAR).  During the event, 22 renowned invited french or indian speakers gave lectures on their areas of expertise within the field of matrix analysis or processing. From these talks, a total of 17 original contribution or state-of-the-art chapters have been assembled in this volume. All articles were thoroughly peer-reviewed and improved, according to the suggestions of the international referees. The 17 contributions presented  are organized in three parts: (1) State-of-the-art surveys & original matrix theory work, (2) Advanced matrix theory for radar processing, and (3) Matrix-based signal processing applications.  

  2. Design and Evaluation of an Oral Floating Matrix Tablet of ...

    African Journals Online (AJOL)

    Purpose: To develop floating matrix tablets of salbutamol sulphate using ethyl cellulose and acrycoat S-100 as polymers, and sodium bicarbonate, citric acid and tartaric acid as gas generating agents. Methods: Twenty four formulations were prepared and segregated into four major categories, A to D. The floating tablets ...

  3. dependent/calmodulin- stimulated protein kinase from moss

    Indian Academy of Sciences (India)

    Unknown

    stimulated protein kinase; CDPK, calmodulin domain-like protein kinase; KM14, 14 amino acid synthetic peptide; .... used were obtained from Sigma Chemical Company, USA, ..... Plant chimeric Ca2+/Calmodulin-dependent protein kinase.

  4. 2016 MATRIX annals

    CERN Document Server

    Praeger, Cheryl; Tao, Terence

    2018-01-01

    MATRIX is Australia’s international, residential mathematical research institute. It facilitates new collaborations and mathematical advances through intensive residential research programs, each lasting 1-4 weeks. This book is a scientific record of the five programs held at MATRIX in its first year, 2016: Higher Structures in Geometry and Physics (Chapters 1-5 and 18-21); Winter of Disconnectedness (Chapter 6 and 22-26); Approximation and Optimisation (Chapters 7-8); Refining C*-Algebraic Invariants for Dynamics using KK-theory (Chapters 9-13); Interactions between Topological Recursion, Modularity, Quantum Invariants and Low-dimensional Topology (Chapters 14-17 and 27). The MATRIX Scientific Committee selected these programs based on their scientific excellence and the participation rate of high-profile international participants. Each program included ample unstructured time to encourage collaborative research; some of the longer programs also included an embedded conference or lecture series. The artic...

  5. Matrix interdiction problem

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Feng [Los Alamos National Laboratory; Kasiviswanathan, Shiva [Los Alamos National Laboratory

    2010-01-01

    In the matrix interdiction problem, a real-valued matrix and an integer k is given. The objective is to remove k columns such that the sum over all rows of the maximum entry in each row is minimized. This combinatorial problem is closely related to bipartite network interdiction problem which can be applied to prioritize the border checkpoints in order to minimize the probability that an adversary can successfully cross the border. After introducing the matrix interdiction problem, we will prove the problem is NP-hard, and even NP-hard to approximate with an additive n{gamma} factor for a fixed constant {gamma}. We also present an algorithm for this problem that achieves a factor of (n-k) mUltiplicative approximation ratio.

  6. Dynamic Matrix Rank

    DEFF Research Database (Denmark)

    Frandsen, Gudmund Skovbjerg; Frandsen, Peter Frands

    2009-01-01

    We consider maintaining information about the rank of a matrix under changes of the entries. For n×n matrices, we show an upper bound of O(n1.575) arithmetic operations and a lower bound of Ω(n) arithmetic operations per element change. The upper bound is valid when changing up to O(n0.575) entries...... in a single column of the matrix. We also give an algorithm that maintains the rank using O(n2) arithmetic operations per rank one update. These bounds appear to be the first nontrivial bounds for the problem. The upper bounds are valid for arbitrary fields, whereas the lower bound is valid for algebraically...... closed fields. The upper bound for element updates uses fast rectangular matrix multiplication, and the lower bound involves further development of an earlier technique for proving lower bounds for dynamic computation of rational functions....

  7. MATLAB matrix algebra

    CERN Document Server

    Pérez López, César

    2014-01-01

    MATLAB is a high-level language and environment for numerical computation, visualization, and programming. Using MATLAB, you can analyze data, develop algorithms, and create models and applications. The language, tools, and built-in math functions enable you to explore multiple approaches and reach a solution faster than with spreadsheets or traditional programming languages, such as C/C++ or Java. MATLAB Matrix Algebra introduces you to the MATLAB language with practical hands-on instructions and results, allowing you to quickly achieve your goals. Starting with a look at symbolic and numeric variables, with an emphasis on vector and matrix variables, you will go on to examine functions and operations that support vectors and matrices as arguments, including those based on analytic parent functions. Computational methods for finding eigenvalues and eigenvectors of matrices are detailed, leading to various matrix decompositions. Applications such as change of bases, the classification of quadratic forms and ...

  8. Elementary matrix algebra

    CERN Document Server

    Hohn, Franz E

    2012-01-01

    This complete and coherent exposition, complemented by numerous illustrative examples, offers readers a text that can teach by itself. Fully rigorous in its treatment, it offers a mathematically sound sequencing of topics. The work starts with the most basic laws of matrix algebra and progresses to the sweep-out process for obtaining the complete solution of any given system of linear equations - homogeneous or nonhomogeneous - and the role of matrix algebra in the presentation of useful geometric ideas, techniques, and terminology.Other subjects include the complete treatment of the structur

  9. Complex matrix model duality

    International Nuclear Information System (INIS)

    Brown, T.W.

    2010-11-01

    The same complex matrix model calculates both tachyon scattering for the c=1 non-critical string at the self-dual radius and certain correlation functions of half-BPS operators in N=4 super- Yang-Mills. It is dual to another complex matrix model where the couplings of the first model are encoded in the Kontsevich-like variables of the second. The duality between the theories is mirrored by the duality of their Feynman diagrams. Analogously to the Hermitian Kontsevich- Penner model, the correlation functions of the second model can be written as sums over discrete points in subspaces of the moduli space of punctured Riemann surfaces. (orig.)

  10. Complex matrix model duality

    Energy Technology Data Exchange (ETDEWEB)

    Brown, T.W.

    2010-11-15

    The same complex matrix model calculates both tachyon scattering for the c=1 non-critical string at the self-dual radius and certain correlation functions of half-BPS operators in N=4 super- Yang-Mills. It is dual to another complex matrix model where the couplings of the first model are encoded in the Kontsevich-like variables of the second. The duality between the theories is mirrored by the duality of their Feynman diagrams. Analogously to the Hermitian Kontsevich- Penner model, the correlation functions of the second model can be written as sums over discrete points in subspaces of the moduli space of punctured Riemann surfaces. (orig.)

  11. Follicle-Stimulating Hormone Increases the Risk of Postmenopausal Osteoporosis by Stimulating Osteoclast Differentiation.

    Directory of Open Access Journals (Sweden)

    Jie Wang

    Full Text Available The objectives of this study were to observe the changes in follicle-stimulating hormone (FSH and bone mineral density (BMD in postmenopausal women, to research the relationship between FSH and postmenopausal osteoporosis, and to observe the effects of FSH on osteoclast differentiation in RAW264.7 cells.We analyzed 248 postmenopausal women with normal bone metabolism. A radioimmunoassay (RIA was used to detect serum FSH, luteinizing hormone (LH, and estradiol (E2. Dual-energy X-ray absorptiometry was used to measure forearm BMD. Then, we analyzed the age-related changes in serum FSH, LH and E2. Additionally, FSH serum concentrations were compared between a group of postmenopausal women with osteoporosis and a control group. Osteoclasts were induced from RAW264.7 cells in vitro by receptor activator of nuclear factor kappa B ligand (RANKL, and these cells were treated with 0, 5, 10, and 20 ng/ml FSH. After the osteoclasts matured, tartrate-resistant acid phosphatase (TRAP staining was used to identify osteoclasts, and the mRNA expression levels of genes involved in osteoclastic phenotypes and function, such as receptor activator of NF-κB (Rank, Trap, matrix metalloproteinase-9 (Mmp-9 and Cathepsin K, were detected in different groups using real-time PCR (polymerase chain reaction.1. FSH serum concentrations in postmenopausal women with osteoporosis increased notably compared with the control group. 2. RANKL induced RAW264.7 cell differentiation into mature osteoclasts in vitro. 3. FSH increased mRNA expression of genes involved in osteoclastic phenotypes and function, such as Rank, Trap, Mmp-9 and Cathepsin K, in a dose-dependent manner.The circulating concentration of FSH may play an important role in the acceleration of bone loss in postmenopausal women. FSH increases osteoclastogenesis in vitro.

  12. Regulation of proliferation of embryonic heart mesenchyme: Role of transforming growth factor-beta 1 and the interstitial matrix

    International Nuclear Information System (INIS)

    Choy, M.; Armstrong, M.T.; Armstrong, P.B.

    1990-01-01

    Proliferation of atrioventricular cushion mesenchyme of the embryonic avian heart maintained in three-dimensional aggregate culture is stimulated by interaction with the interstitial matrix. Chicken serum or transforming growth factor-beta 1, which stimulates proliferation, induces matrix deposition in regions of the aggregate showing high labeling indices with tritiated thymidine. Dispersed heart mesenchyme interstitial matrix introduced into serum-free culture is incorporated into the aggregate and stimulates cellular proliferation similar to serum or transforming growth factor-beta 1. Proliferation is reversibly inhibited by the peptide Gly-Arg-Gly-Asp-Ser-Pro. It is suggested that transforming growth factor-beta 1 stimulates the production of interstitial matrix and that a sufficient stimulus for proliferation in this system is the presence of the matrix, which acts as the adhesive support for cellular anchorage

  13. Ethical Matrix Manual

    NARCIS (Netherlands)

    Mepham, B.; Kaiser, M.; Thorstensen, E.; Tomkins, S.; Millar, K.

    2006-01-01

    The ethical matrix is a conceptual tool designed to help decision-makers (as individuals or working in groups) reach sound judgements or decisions about the ethical acceptability and/or optimal regulatory controls for existing or prospective technologies in the field of food and agriculture.

  14. Combinatorial matrix theory

    CERN Document Server

    Mitjana, Margarida

    2018-01-01

    This book contains the notes of the lectures delivered at an Advanced Course on Combinatorial Matrix Theory held at Centre de Recerca Matemàtica (CRM) in Barcelona. These notes correspond to five series of lectures. The first series is dedicated to the study of several matrix classes defined combinatorially, and was delivered by Richard A. Brualdi. The second one, given by Pauline van den Driessche, is concerned with the study of spectral properties of matrices with a given sign pattern. Dragan Stevanović delivered the third one, devoted to describing the spectral radius of a graph as a tool to provide bounds of parameters related with properties of a graph. The fourth lecture was delivered by Stephen Kirkland and is dedicated to the applications of the Group Inverse of the Laplacian matrix. The last one, given by Ángeles Carmona, focuses on boundary value problems on finite networks with special in-depth on the M-matrix inverse problem.

  15. Visualizing Matrix Multiplication

    Science.gov (United States)

    Daugulis, Peteris; Sondore, Anita

    2018-01-01

    Efficient visualizations of computational algorithms are important tools for students, educators, and researchers. In this article, we point out an innovative visualization technique for matrix multiplication. This method differs from the standard, formal approach by using block matrices to make computations more visual. We find this method a…

  16. Challenging the CSCW matrix

    DEFF Research Database (Denmark)

    Jørnø, Rasmus Leth Vergmann; Gynther, Karsten; Christensen, Ove

    2014-01-01

    useful information, we question whether the axis of time and space comprising the matrix pertains to relevant defining properties of the tools, technology or learning environments to which they are applied. Subsequently we offer an example of an Adobe Connect e-learning session as an illustration...

  17. [Transcranial magnetic stimulation].

    Science.gov (United States)

    Tormos, J M; Catalá, M D; Pascual-Leone, A

    Transcranial magnetic stimulation (TMS) permits stimulation of the cerebral cortex in humans without requiring open access to the brain and is one of the newest tools available in neuroscience. There are two main types of application: single-pulse TMS and repetitive TMS. The magnetic stimulator is composed of a series of capacitors that store the voltage necessary to generate a stimulus of the sufficient intensity of generate an electric field in the stimulation coil. The safety of TMS is supported by the considerable experience derived from studies involving electrical stimulation of the cortex in animals and humans, and also specific studies on the safety of TMS in humans. In this article we review historical and technical aspects of TMS, describe its adverse effects and how to avoid them, summarize the applications of TMS in the investigation of different cerebral functions, and discuss the possibility of using TMS for the treatment of neuropsychiatric disorders.

  18. In vivo imaging of extracellular matrix remodeling by tumor-associated fibroblasts

    DEFF Research Database (Denmark)

    Perentes, Jean Y; McKee, Trevor D; Ley, Carsten D

    2009-01-01

    Here we integrated multiphoton laser scanning microscopy and the registration of second harmonic generation images of collagen fibers to overcome difficulties in tracking stromal cell-matrix interactions for several days in live mice. We show that the matrix-modifying hormone relaxin increased...... tumor-associated fibroblast (TAF) interaction with collagen fibers by stimulating beta1-integrin activity, which is necessary for fiber remodeling by matrix metalloproteinases....

  19. Serum insulin, glucose and non esterified fatty acids after administration of follicle-stimulating and luteinizing hormones in bitches Modificaciones de la glucemia, insulina y ácidos grasos no esterificados durante la sobrecarga de glucosa o insulina en perras tratadas con hormona folículo-estimulante y luteinizante

    OpenAIRE

    A. Renauld; N. V. Gomez; J. D. Scaramal; D. Garrido; M. M Wanke

    2003-01-01

    This paper reports the effect of the simultaneous administration of follicle-stimulating (FSH) and luteinizing hormones (LH) on serum glucose, insulin and nonesterified fatty acid responses after glucose or insulin challenge. The animals were originally at anestrous. FSH (dose 2.5 U/kg body wt.) and LH (0.27 U/kg body wt.) were sc injected on days 1, 4, 8 and 11. Vaginal smears were obtained daily. Six untreated controls at anestrous and six treated bitches reaching proestrous were used. Gluc...

  20. Music acupuncture stimulation method.

    Science.gov (United States)

    Brătilă, F; Moldovan, C

    2007-01-01

    Harmonic Medicine is the model using the theory that the body rhythms synchronize to an outer rhythm applied for therapeutic purpose, can restores the energy balance in acupuncture channels and organs and the condition of well-being. The purpose of this scientific work was to demonstrate the role played by harmonic sounds in the stimulation of the Lung (LU) Meridian (Shoutaiyin Feijing) and of the Kidney (KI) Meridian (Zushaoyin Shenjing). It was used an original method that included: measurement and electronic sound stimulation of the Meridian Entry Point, measurement of Meridian Exit Point, computer data processing, bio feed-back adjustment of the music stimulation parameters. After data processing, it was found that the sound stimulation of the Lung Meridian Frequency is optimal between 122 Hz and 128 Hz, with an average of 124 Hz (87% of the subjects) and for Kidney Meridian from 118 Hz to 121 Hz, with an average of 120 Hz (67% of the subjects). The acupuncture stimulation was more intense for female subjects (> 7%) than for the male ones. We preliminarily consider that an informational resonance phenomenon can be developed between the acupuncture music stimulation frequency and the cellular dipole frequency, being a really "resonant frequency signature" of an acupoint. The harmonic generation and the electronic excitation or low-excitation status of an acupuncture point may be considered as a resonance mechanism. By this kind of acupunctural stimulation, a symphony may act and play a healer role.

  1. Broadband stimulated Raman spectroscopy in the deep ultraviolet region

    Science.gov (United States)

    Kuramochi, Hikaru; Fujisawa, Tomotsumi; Takeuchi, Satoshi; Tahara, Tahei

    2017-09-01

    We report broadband stimulated Raman measurements in the deep ultraviolet (DUV) region, which enables selective probing of the aromatic amino acid residues inside proteins through the resonance enhancement. We combine the narrowband DUV Raman pump pulse (1000 cm-1) to realize stimulated Raman measurements covering a >1500 cm-1 spectral window. The stimulated Raman measurements for neat solvents, tryptophan, tyrosine, and glucose oxidase are performed using 240- and 290-nm Raman pump, highlighting the high potential of the DUV stimulated Raman probe for femtosecond time-resolved study of proteins.

  2. Paths correlation matrix.

    Science.gov (United States)

    Qian, Weixian; Zhou, Xiaojun; Lu, Yingcheng; Xu, Jiang

    2015-09-15

    Both the Jones and Mueller matrices encounter difficulties when physically modeling mixed materials or rough surfaces due to the complexity of light-matter interactions. To address these issues, we derived a matrix called the paths correlation matrix (PCM), which is a probabilistic mixture of Jones matrices of every light propagation path. Because PCM is related to actual light propagation paths, it is well suited for physical modeling. Experiments were performed, and the reflection PCM of a mixture of polypropylene and graphite was measured. The PCM of the mixed sample was accurately decomposed into pure polypropylene's single reflection, pure graphite's single reflection, and depolarization caused by multiple reflections, which is consistent with the theoretical derivation. Reflection parameters of rough surface can be calculated from PCM decomposition, and the results fit well with the theoretical calculations provided by the Fresnel equations. These theoretical and experimental analyses verify that PCM is an efficient way to physically model light-matter interactions.

  3. Partially separable t matrix

    International Nuclear Information System (INIS)

    Sasakawa, T.; Okuno, H.; Ishikawa, S.; Sawada, T.

    1982-01-01

    The off-shell t matrix is expressed as a sum of one nonseparable and one separable terms so that it is useful for applications to more-than-two body problems. All poles are involved in this one separable term. Both the nonseparable and the separable terms of the kernel G 0 t are regular at the origin. The nonseparable term of this kernel vanishes at large distances, while the separable term behaves asymptotically as the spherical Hankel function. These properties make our expression free from defects inherent in the Jost or the K-matrix expressions, and many applications are anticipated. As the application, a compact expression of the many-level formula is presented. Also the application is suggested to the breakup threebody problem based on the Faddeev equation. It is demonstrated that the breakup amplitude is expressed in a simple and physically interesting form and we can calculate it in coordinate space

  4. Exactly soluble matrix models

    International Nuclear Information System (INIS)

    Raju Viswanathan, R.

    1991-09-01

    We study examples of one dimensional matrix models whose potentials possess an energy spectrum that can be explicitly determined. This allows for an exact solution in the continuum limit. Specifically, step-like potentials and the Morse potential are considered. The step-like potentials show no scaling behaviour and the Morse potential (which corresponds to a γ = -1 model) has the interesting feature that there are no quantum corrections to the scaling behaviour in the continuum limit. (author). 5 refs

  5. Inside the NIKE matrix

    OpenAIRE

    Brenner, Barbara; Schlegelmilch, Bodo B.; Ambos, Björn

    2013-01-01

    This case describes how Nike, a consumer goods company with an ever expanding portfolio and a tremendous brand value, manages the tradeoff between local responsiveness and global integration. In particular, the case highlights Nike's organizational structure that consists of a global matrix organization that is replicated at a regional level for the European market. While this organizational structure allows Nike to respond to local consumer tastes it also ensures that the company benefits f...

  6. A matrix contraction process

    Science.gov (United States)

    Wilkinson, Michael; Grant, John

    2018-03-01

    We consider a stochastic process in which independent identically distributed random matrices are multiplied and where the Lyapunov exponent of the product is positive. We continue multiplying the random matrices as long as the norm, ɛ, of the product is less than unity. If the norm is greater than unity we reset the matrix to a multiple of the identity and then continue the multiplication. We address the problem of determining the probability density function of the norm, \

  7. Matrix String Theory

    CERN Document Server

    Dijkgraaf, R; Verlinde, Herman L

    1997-01-01

    Via compactification on a circle, the matrix model of M-theory proposed by Banks et al suggests a concrete identification between the large N limit of two-dimensional N=8 supersymmetric Yang-Mills theory and type IIA string theory. In this paper we collect evidence that supports this identification. We explicitly identify the perturbative string states and their interactions, and describe the appearance of D-particle and D-membrane states.

  8. Matrix groups for undergraduates

    CERN Document Server

    Tapp, Kristopher

    2016-01-01

    Matrix groups touch an enormous spectrum of the mathematical arena. This textbook brings them into the undergraduate curriculum. It makes an excellent one-semester course for students familiar with linear and abstract algebra and prepares them for a graduate course on Lie groups. Matrix Groups for Undergraduates is concrete and example-driven, with geometric motivation and rigorous proofs. The story begins and ends with the rotations of a globe. In between, the author combines rigor and intuition to describe the basic objects of Lie theory: Lie algebras, matrix exponentiation, Lie brackets, maximal tori, homogeneous spaces, and roots. This second edition includes two new chapters that allow for an easier transition to the general theory of Lie groups. From reviews of the First Edition: This book could be used as an excellent textbook for a one semester course at university and it will prepare students for a graduate course on Lie groups, Lie algebras, etc. … The book combines an intuitive style of writing w...

  9. Extracellular matrix structure.

    Science.gov (United States)

    Theocharis, Achilleas D; Skandalis, Spyros S; Gialeli, Chrysostomi; Karamanos, Nikos K

    2016-02-01

    Extracellular matrix (ECM) is a non-cellular three-dimensional macromolecular network composed of collagens, proteoglycans/glycosaminoglycans, elastin, fibronectin, laminins, and several other glycoproteins. Matrix components bind each other as well as cell adhesion receptors forming a complex network into which cells reside in all tissues and organs. Cell surface receptors transduce signals into cells from ECM, which regulate diverse cellular functions, such as survival, growth, migration, and differentiation, and are vital for maintaining normal homeostasis. ECM is a highly dynamic structural network that continuously undergoes remodeling mediated by several matrix-degrading enzymes during normal and pathological conditions. Deregulation of ECM composition and structure is associated with the development and progression of several pathologic conditions. This article emphasizes in the complex ECM structure as to provide a better understanding of its dynamic structural and functional multipotency. Where relevant, the implication of the various families of ECM macromolecules in health and disease is also presented. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Standard Errors for Matrix Correlations.

    Science.gov (United States)

    Ogasawara, Haruhiko

    1999-01-01

    Derives the asymptotic standard errors and intercorrelations for several matrix correlations assuming multivariate normality for manifest variables and derives the asymptotic standard errors of the matrix correlations for two factor-loading matrices. (SLD)

  11. Neutron dosimetry using optically stimulated luminescence

    International Nuclear Information System (INIS)

    Miller, S.D.; Eschbach, P.A.

    1991-06-01

    The addition of thermoluminescent (TL) materials within hydrogenous matrices to detect neutron-induced proton recoils for radiation dosimetry is a well-known concept. Previous attempts to implement this technique have met with limited success, primarily due to the high temperatures required for TL readout and the low melting temperatures of hydrogen-rich plastics. Research in recent years at Pacific Northwest laboratories (PNL) has produced a new Optically Stimulated Luminescence (OSL) technique known as the Cooled Optically Stimulated Luminescence (COSL) that offers, for the first time, the capability of performing extremely sensitive radiation dosimetry at low temperatures. In addition to its extreme sensitivity, the COSL technique offers multiple readout capability, limited fading in a one-year period, and the capability of analyzing single grains within a hydrogenous matrix. 4 refs., 10 figs

  12. Assembly and development of the Pseudomonas aeruginosa biofilm matrix.

    Directory of Open Access Journals (Sweden)

    Luyan Ma

    2009-03-01

    Full Text Available Virtually all cells living in multicellular structures such as tissues and organs are encased in an extracellular matrix. One of the most important features of a biofilm is the extracellular polymeric substance that functions as a matrix, holding bacterial cells together. Yet very little is known about how the matrix forms or how matrix components encase bacteria during biofilm development. Pseudomonas aeruginosa forms environmentally and clinically relevant biofilms and is a paradigm organism for the study of biofilms. The extracellular polymeric substance of P. aeruginosa biofilms is an ill-defined mix of polysaccharides, nucleic acids, and proteins. Here, we directly visualize the product o