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Sample records for acetate pma stimulated

  1. Catecholamine differential modulation of PMA and superantigen stimulated lymphocytes

    SciTech Connect

    Downs, M.O.; Johnson, H.M. )

    1991-03-15

    Neurotransmitters have been demonstrated to be important modulators of immune regulation. The authors have previously demonstrated that the catecholamine agonists isoproterenol (Iso), epinephrine (Epi), and norepinephrine (Nor) are potent inhibitors of IFN{gamma} production by phorbol myristate acetate (PMA) stimulated T-cell lymphoma cell line (L12-R4) with the order of potency being Iso > Epi > Nor. Herein, they describe a differential effect of catecholamine influence on staphylococcal enterotoxin A (SEA) stimulated murine splenic cell cultures. Norepinephrine and to a lesser extent Epi can cause a biphasic modulation of IFN{gamma} production. Inhibition of INF{gamma}was seen in the micromolar range while augmentation occurred at the nanomolar range. In light of previous work, these data suggest that {beta}-adrenergic agonist stimulation of antigen presenting cells (APC) may be immunosuppressive while {alpha}-agonist stimulation immunopotentiating. Further, APC may play a central role in determining the net outcome of catecholamine stimulation by being able to mediate signals from both pathways. This response may represent a peripheral neurotransmitter mediated mechanism for fine tuning' immunoreactivity.

  2. Myristic Acid, A Side Chain of Phorbol Myristate Acetate (PMA), Can Activate Human Polymorphonuclear Leukocytes to Produce Oxygen Radicals More Potently than PMA

    PubMed Central

    Tada, Mika; Ichiishi, Eiichiro; Saito, Rumiko; Emoto, Natsumi; Niwano, Yoshimi; Kohno, Masahiro

    2009-01-01

    Myristic acid (MyA), which is a saturated fatty acid (C14:0) and a side chain of phorbol 12-myristate 13-acetate (PMA), was examined if MyA stimulates human polymorphonuclear leukocytes (PMNs) to release oxygen radicals comparable to PMA by applying electron paramagnetic resonance (EPR)-spin-trapping method. When MyA was added to isolated human PMNs, spin adducts of 5,5-dimethyl-1-pyrroline-N-oxide (DMPO)-OH and DMPO-OOH were time-dependently observed. The amounts of these spin adducts were larger than those of PMNs stimulated by PMA. These results clearly show that MyA is more potent agent to prime human PMNs than PMA, in a point of view of not only O2·− but also ·OH production. This fact calls attention that too much intake of MyA that is known to be contained vegetable oils can lead to crippling effect through uncontrolled production of reactive oxygen species. PMID:19902021

  3. Roles of phospholipase D in phorbol myristate acetate-stimulated neutrophil respiratory burst.

    PubMed

    Hu, Tianhui; Liu, Zhaoxia; Shen, Xun

    2011-03-01

    The phorbol myristate acetate (PMA) stimulated nutrophil respiratory burst has been considered to simply involve the activation of protein kinase C (PKC). However, the PLD activity was also increased by 10-fold in human neutrophils stimulated with 100 nM PMA. Unexpectedly, U73122, an inhibitor of phospholipase C, was found to significantly inhibit PMA-stimulated respiratory burst in human neutrophils. U73122 at the concentrations, which were sufficient to inhibit the respiratory burst completely, caused partial inhibition of the PLD activity but no inhibition on PKC translocation and activation, suggesting that PLD activity is also required in PMA-stimulated respiratory burst. Using 1-butanol, a PLD substrate, to block phosphatidic acid (PA) generation, the PMA-stimulated neutrophil respiratory burst was also partially inhibited, further indicating that PLD activation, possibly its hydrolytic product PA and diacylglycerol (DAG), is involved in PMA-stimulated respiratory burst. Since GF109203X, an inhibitor of PKC that could completely inhibit the respiratory burst in PMA-stimulated neutrophils, also caused certain suppression of PLD activation, it may suggest that PLD activation in PMA-stimulated neutrophils might be, to some extent, PKC dependent. To further study whether PLD contributes to the PMA stimulated respiratory burst through itself or its hydrolytic product, 1,2-dioctanoyl-sn-glycerol, an analogue of DAG , was used to prime cells at low concentration, and it reversed the inhibition of PMA-stimulated respiratory burst by U73122. The results indicate that U73122 may act as an inhibitor of PLD, and PLD activation is required in PMA-stimulated respiratory burst.

  4. Inhibitory effect of arctigenin on lymphocyte activation stimulated with PMA/ionomycin.

    PubMed

    Sun, Cheng-Hong; Lai, Xin-Qiang; Zhang, Li; Yao, Jing-Chun; Guan, Yong-Xia; Pan, Li-Hong; Yan, Ying

    2014-04-01

    This study investigated the effect of arctigenin (Arc) on the cell activation, cytokines expression, proliferation, and cell-cycle distribution of mouse T lymphocytes. Mouse lymphocytes were prepared from lymph node and treated with Phorbol-12-myristate-13-acetate (PMA)/Ionimycin (Ion) and/or Arc. CD69, CD25, cytokines, proliferation and cell cycle were assayed by flow cytometry. The results showed that, at concentrations of less than 1.00 micromol x L(-1), Arc expressed non-obvious cell damage to cultured lymphocytes, however, it could significantly down-regulate the expression of CD69 and CD25, as well as TNF-alpha, IFN-gamma, IL-2, IL-4, IL-6 and IL-10 on PMA/Ion stimulated lymphocytes. At the same time, Arc could also inhibit the proliferation of PMA/Ion-activated lymphocytes and exhibited lymphocyte G 0/G1 phase cycle arrest. These results suggest that Arc possesses significant anti-inflammatory effects that may be mediated through the regulation of cell activation, cytokines expression and cell proliferation.

  5. Inhibitory effect of arctigenin on lymphocyte activation stimulated with PMA/ionomycin.

    PubMed

    Sun, Cheng-Hong; Lai, Xin-Qiang; Zhang, Li; Yao, Jing-Chun; Guan, Yong-Xia; Pan, Li-Hong; Yan, Ying

    2014-04-01

    This study investigated the effect of arctigenin (Arc) on the cell activation, cytokines expression, proliferation, and cell-cycle distribution of mouse T lymphocytes. Mouse lymphocytes were prepared from lymph node and treated with Phorbol-12-myristate-13-acetate (PMA)/Ionimycin (Ion) and/or Arc. CD69, CD25, cytokines, proliferation and cell cycle were assayed by flow cytometry. The results showed that, at concentrations of less than 1.00 micromol x L(-1), Arc expressed non-obvious cell damage to cultured lymphocytes, however, it could significantly down-regulate the expression of CD69 and CD25, as well as TNF-alpha, IFN-gamma, IL-2, IL-4, IL-6 and IL-10 on PMA/Ion stimulated lymphocytes. At the same time, Arc could also inhibit the proliferation of PMA/Ion-activated lymphocytes and exhibited lymphocyte G 0/G1 phase cycle arrest. These results suggest that Arc possesses significant anti-inflammatory effects that may be mediated through the regulation of cell activation, cytokines expression and cell proliferation. PMID:24974465

  6. The insulin-like effects of phorbol myristate acetate (PMA) in the isolated fat cell

    SciTech Connect

    Solomon, S.S.; Palazzolo, M. )

    1989-01-01

    Recent data from many laboratories suggest that insulin stimulates diacylglycerol formation. Data presented in this manuscript demonstrate an insulin-like effect of PMA, a tumor promoting agent that mimics the action of diacylglycerol, in isolated adipocytes on; (a) glucose oxidation using uniformly labelled, C-1-labelled and C-6-labelled glucose, (b) epinephrine-induced lipolysis and (c) low Km cAMP phosphodiesterase activity. Additionally, a lipolytic effect of PMA is identified when unopposed by epinephrine. These data not only demonstrate an insulin-like effect of phorbol esters in adipose tissue but they lend support to the concept of diacylglycerol involvement in the mechanism of insulin action.

  7. The anti-inflammatory effect of the SOCC blocker SK&F 96365 on mouse lymphocytes after stimulation by Con A or PMA/ionomycin.

    PubMed

    Ye, Yanxia; Zhang, Yaxing; Lu, Xiaoyu; Huang, Xiuyan; Zeng, Xiangfeng; Lai, Xinqiang; Zeng, Yaoying

    2011-09-01

    SK&F 96365, 51-(beta-[3-(p-methoxyphenyl)-propyloxy]-p-methoxyphenethyl)-1H-imidazole hydrochloride, has emerged as a useful pharmacological tool in the study of store-operated Ca²⁺ entry (SOCE). But the precise molecular mechanism and effect of SK&F 96365 on mouse lymphocytes are still not well determined. This study investigated the pharmacological profile of SK&F 96365 on mouse lymphocytes stimulated by mitogen concanavalin A (Con A) or by a combination of a protein kinase C (PKC) activator, phorbol 12-myristate 13-acetate (PMA) and a calcium ionophore, ionomycin in vitro. Our results showed that SK&F 96365 pre-treatment diminished the cytosolic calcium rise on lymphocytes induced by ionomycin, PMA/ionomycin, and thapsigargin (TG), respectively. CFDA-SE staining results showed that SK&F 96365 (5-20 μM) inhibited both Con A- and PMA/ionomycin-induced lymphocytes proliferation in a time- and dose-dependent manner. Upon the same stimulation, SK&F 96365 inhibited the expression of CD69 and CD25 on CD3⁺ T lymphocytes in a dose-dependent manner. The cell cycle analyzing results showed that SK&F 96365 caused a G0/G1 phase cell cycle arrest on both Con A- and PMA/ionomycin-activated lymphocytes in a dose-dependent manner. In addition, SK&F 96365 induced a decrease in mitochondrial membrane potential (ΔΨm) and promoted mitochondrial permeability transition (MPT) in both Con A- and PMA/ionomycin-activated lymphocytes. Furthermore, SK&F 96365 significantly inhibited the production of proinflammatory cytokines (interferon (IFN)-γ and tumor necrosis factor (TNF)), and the anti-inflammatory cytokine (IL-10) on both Con A- and PMA/ionomycin-activated lymphocytes. SK&F 96365 did not induce a statistically significant increase in levels of proinflammatory IL-6 and monocyte chemoattractant protein-1 (MCP-1) but of IL-12p70 upon the stimulation of Con A, whereas these three cytokines were markedly inhibited by it upon the stimulation of PMA/ionomycin. This finding

  8. Cannabinoids inhibit the activation of ERK MAPK in PMA/Io-stimulated mouse splenocytes.

    PubMed

    Faubert Kaplan, Barbara L; Kaminski, Norbert E

    2003-10-01

    The mechanism of action of immune suppression by cannabinoids involves suppression of interleukin-2 (IL-2) production in phorbol ester plus calcium ionophore (PMA/Io)-stimulated lymphocytes. This decrease in IL-2 was due to inhibition of activator protein-1 (AP-1) and nuclear factor of activated T cells (NF-AT) transcription factors, both of which depend on proteins that are regulated by the extracellular signal-regulated kinase subgroup of the mitogen-activated protein kinases (ERK MAPK). Thus, the objective of the present study was to characterize the effects of cannabinoid compounds on ERK MAPK under conditions where IL-2 expression was suppressed. Using the MEK inhibitor PD098059 in order to assess the role of ERK MAPK in PMA/Io-stimulated splenocytes (SPLC), it was determined that IL-2 production and expression of c-fos and c-jun nuclear protein expression depended on activation of ERK MAPK. In response to PMA/Io, expression of nuclear phosphorylated ERK MAPK was rapidly induced, peaked at approximately 15 min, and was sustained for up to 240 min. Pretreatment with cannabinol (CBN) inhibited expression of phosphorylated ERK MAPK at several time points up to 240 min post cellular activation. Furthermore, WIN-55212-2, a synthetic cannabinoid, inhibited expression of phosphorylated ERK MAPK at 240 min post cellular activation. CBN did not induce activation of ERK MAPK in the absence of PMA/Io. Collectively, these studies suggest that cannabinoid-induced inhibition of IL-2 in PMA/Io-stimulated splenocytes might be due, in part, to inhibition of ERK MAPK activation.

  9. Adenosine (ADO) prevents phorbol myristate acetate (PMA) injury in rabbit lungs: Role of leukotrienes (LT)

    SciTech Connect

    Zanaboni, P.; Bradley, J.; Webster, R.; Baudendistel. L.; Dahms, T. )

    1991-03-11

    Pretreatment with ADO prevents the PMA-induced increase in the fluid filtration coefficient (K{sub f}) in isolated perfused rabbit lungs. ADO can block the synthesis of LTs. This study determined whether the protective effect of ADO in PMA induced injury was due to decreased LT production. Isolated rabbit lungs were perfused with a 1:1 mixture of blood and 6% albumin in Krebs-Henseleit buffer. K{sub f} was measured after hemodynamic and weight stabilization and then 30 min after PMA. Perfusate samples were collected after each K{sub f} measurement for determination of LTC{sub 4} and LTD{sub 4} by RIA. The specific role of LT was studied by pretreating with MK-886, a LT synthesis inhibitor. In the vehicle pretreatment group, PMA caused a significant increase in K{sub f} and LTC{sub 4} + LTD{sub 4}. ADO inhibited both the increase in K{sub f} and in LTC{sub 4} + LTD{sub 4}. Pretreatment with MK-886 blocked the PMA-induced increase in LT but did not inhibit the K{sub f} increase. ADO alters the production of LTC{sub 4} + LTD{sub 4} following PMA; but it is probably not the mechanism by which ADO prevents the increase in microvascular permeability.

  10. Phenyl mercuric acetate (PMA): mercury-bearing flexible gymnasium floors in schools--evaluation of hazards and controlled abatement.

    PubMed

    Beaulieu, Harry J; Beaulieu, Serrita; Brown, Chris

    2008-06-01

    Phenyl mercuric acetate (PMA) historically has been used as a catalyst in polyurethane systems. In the 1950s-1970s, PMA was used as a catalyst in the 3M Tartan brand polyurethane flexible floors that were installed commonly in school gymnasiums. Mercury vapor is released into air above the surface of these floors. Sampling mercury in bulk flooring material and mercury vapor in air was conducted in nine Idaho schools in the spring of 2006. These evaluations were conducted in response to concerns by school officials that the floors could contain mercury and could release the mercury vapor into the air, presenting a potential health hazard for students, staff, and visitors. Controlled abatement was conducted in one school where remodeling would impact the mercury-bearing flexible gym floors ( approximately 9,000 ft(2) total). The controlled abatement consisted of containment of the work area with negative air technology; worker protection, including mercury-specific training, use of personal protective equipment, and biological and exposure monitoring; and environmental protection, including proper disposal of mercury-bearing hazardous waste material. PMID:18365889

  11. Phenyl mercuric acetate (PMA): mercury-bearing flexible gymnasium floors in schools--evaluation of hazards and controlled abatement.

    PubMed

    Beaulieu, Harry J; Beaulieu, Serrita; Brown, Chris

    2008-06-01

    Phenyl mercuric acetate (PMA) historically has been used as a catalyst in polyurethane systems. In the 1950s-1970s, PMA was used as a catalyst in the 3M Tartan brand polyurethane flexible floors that were installed commonly in school gymnasiums. Mercury vapor is released into air above the surface of these floors. Sampling mercury in bulk flooring material and mercury vapor in air was conducted in nine Idaho schools in the spring of 2006. These evaluations were conducted in response to concerns by school officials that the floors could contain mercury and could release the mercury vapor into the air, presenting a potential health hazard for students, staff, and visitors. Controlled abatement was conducted in one school where remodeling would impact the mercury-bearing flexible gym floors ( approximately 9,000 ft(2) total). The controlled abatement consisted of containment of the work area with negative air technology; worker protection, including mercury-specific training, use of personal protective equipment, and biological and exposure monitoring; and environmental protection, including proper disposal of mercury-bearing hazardous waste material.

  12. The effect of lipopolysaccharide (LPS) and phorbol 12-myristate 13-acetate (PMA) on whole blood oxidative response as assessed by luminol-amplified chemiluminescence in dairy cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The differences between lipopolysaccharide (LPS) and phorbol 12-myristate 13-acetate (PMA) on whole blood oxidative response using luminol-amplified chemiluminescence (CL) are currently unknown in cattle. Luminol-dependent CL measures the amount of reactive oxygen species released from leukocytes a...

  13. Stimulation of urokinase-type plasminogen activator receptor expression by PMA requires JNK1-dependent and -independent signaling modules.

    PubMed

    Gum, R; Juarez, J; Allgayer, H; Mazar, A; Wang, Y; Boyd, D

    1998-07-16

    The urokinase-type plasminogen activator receptor (u-PAR) has been implicated in tumor progression, and previous studies have shown that the expression of this gene is strongly up-regulated by PMA. Although the signaling mechanism by which PMA modulates u-PAR expression is not known, the effect of this phorbol ester on the expression of other genes has been ascribed to activation of the c-Raf-1-ERK signaling pathway. However, in the current study we examined an alternate possibility that the inductive effect of PMA on u-PAR expression also required a JNK1-dependent signaling cascade usually associated with stress-inducing stimuli. PMA treatment of the u-PAR-deficient OVCAR-3 ovarian cancer cells, which contain low JNK activities, resulted in a rapid (5 min) increase in JNK activity. Maximal JNK activity (12-fold induction) occurred after 30 min; this preceding the earliest detected rise in u-PAR protein (2 h). Dose-response studies with PMA also indicated that the increased JNK activity was tightly correlated with elevated u-PAR protein levels. The stimulation of u-PAR promoter activity by PMA required an intact upstream AP-1 motif (-184) and in PMA-treated cells this motif was bound with c-Jun as indicated from mobility shift assays. PMA up-regulated the c-Jun trans acting activity as indicated by the higher activity of a GAL4-regulated luciferase reporter in phorbol-ester-treated cells co-transfected with an expression vector encoding the c-Jun transactivation domain fused to the GAL4 DNA-binding domain. The ability of PMA to stimulate u-PAR promoter activity was effectively titrated out by the co-expression of either a kinase-defective JNK1 or a dominant negative MEKK1 the latter being an upstream activator of JNK1. Conversely, u-PAR promoter activity was stimulated by the co-expression of a constitutively active MEKK1 and this induction was antagonized by the inclusion of the kinase-defective JNK1 plasmid. We also determined the biological significance of the

  14. 12-tetradecanoyl-phorbol-13-acetate (PMA) produces injury to isolated rat lungs in the presence and absence of perfused neutrophils

    SciTech Connect

    Carpenter, L.J.; Roth, R.A.

    1986-03-01

    PMA produced injury to isolated, perfused rat lungs when eutrophils were added to or omitted from the buffer/albumin perfusion medium. When a high dose of PMA (57 ng/ml) was added to medium devoid of added neutrophils, perfusion pressure and lung weight increased. Together, superoxide dismutase (500 U/ml) and catalase (400 U/ml) had no effect on the increases in lung weight or perfusion pressure. However, papaverine (0.5 mM) prevented both the increase in perfusion pressure and fluid accumulation. When a concentration of PMA (14 ng/ml) that did not by itself cause lungs to accumulate fluid was added to perfusion medium containing neutrophils (1 x 10/sup 8/), perfusion pressures increased and lungs accumulated fluid. This concentration of PMA stimulated neutrophils (1 x 10/sup 8/) to release superoxide. Addition of superoxide dismutase (500 U/ml) and catalase (400 U/ml) to this medium prevented the increase in lung weight, but not the increase in perfusion pressure. Papaverine (0.5 mM) attenuated the increase in perfusion pressure and prevented fluid accumulation in these lungs. In summary, high concentrations of PMA produce lung injury which is independent of oxygen radicals; at lower concentrations it produces injury which is neutrophil-dependent and mediated by oxygen radicals.

  15. Evaluation of Antiradical and Anti-Inflammatory Activities of Ethyl Acetate and Butanolic Subfractions of Agelanthus dodoneifolius (DC.) Polhill & Wiens (Loranthaceae) Using Equine Myeloperoxidase and Both PMA-Activated Neutrophils and HL-60 Cells

    PubMed Central

    Boly, Rainatou; Franck, Thierry; Kohnen, Stephan; Lompo, Marius; Guissou, Innocent Pierre; Dubois, Jacques; Serteyn, Didier; Mouithys-Mickalad, Ange

    2015-01-01

    The ethyl acetate and n-butanolic subfractions of Agelanthus dodoneifolius were investigated for their antioxidant and antimyeloperoxidase (MPO) activities. The reactive oxygen species (ROS) generation was assessed by lucigenin-enhanced chemiluminescence (CL) and dichlorofluorescein- (DCF-) induced fluorescence techniques from phorbol myristate acetate- (PMA-) stimulated equine neutrophils and human myeloid cell line HL-60, respectively. In parallel, the effects of the tested subfractions were evaluated on the total MPO release by stimulated neutrophils and on the specific MPO activity by means of immunological assays. The results showed the potent activity of the butanolic subfraction, at least in respect of the chemiluminescence test (IC50 = 0.3 ± 0.1 µg/mL) and the ELISA and SIEFED assays (IC50 = 2.8 ± 1.2 µg/mL and 1.3 ± 1.0 µg/mL), respectively. However, the ethyl acetate subfraction was found to be the most potent in the DCF assay as at the highest concentration, DCF fluorescence intensity decreases of about 50%. Moreover, we demonstrated that the ethyl acetate subfraction was rich in catechin (16.51%) while it was not easy to identify the main compounds in the butanolic subfraction using the UPLC-MS/MS technique. Nevertheless, taken together, our results provide evidence that Agelanthus dodoneifolius subfractions may represent potential sources of natural antioxidants and of antimyeloperoxidase compounds. PMID:25821497

  16. “Slow” Voltage-Dependent Inactivation of CaV2.2 Calcium Channels Is Modulated by the PKC Activator Phorbol 12-Myristate 13-Acetate (PMA)

    PubMed Central

    Zhu, Lei; McDavid, Sarah; Currie, Kevin P. M.

    2015-01-01

    CaV2.2 (N-type) voltage-gated calcium channels (Ca2+ channels) play key roles in neurons and neuroendocrine cells including the control of cellular excitability, neurotransmitter / hormone secretion, and gene expression. Calcium entry is precisely controlled by channel gating properties including multiple forms of inactivation. “Fast” voltage-dependent inactivation is relatively well-characterized and occurs over the tens-to- hundreds of milliseconds timeframe. Superimposed on this is the molecularly distinct, but poorly understood process of “slow” voltage-dependent inactivation, which develops / recovers over seconds-to-minutes. Protein kinases can modulate “slow” inactivation of sodium channels, but little is known about if/how second messengers control “slow” inactivation of Ca2+ channels. We investigated this using recombinant CaV2.2 channels expressed in HEK293 cells and native CaV2 channels endogenously expressed in adrenal chromaffin cells. The PKC activator phorbol 12-myristate 13-acetate (PMA) dramatically prolonged recovery from “slow” inactivation, but an inactive control (4α-PMA) had no effect. This effect of PMA was prevented by calphostin C, which targets the C1-domain on PKC, but only partially reduced by inhibitors that target the catalytic domain of PKC. The subtype of the channel β-subunit altered the kinetics of inactivation but not the magnitude of slowing produced by PMA. Intracellular GDP-β-S reduced the effect of PMA suggesting a role for G proteins in modulating “slow” inactivation. We postulate that the kinetics of recovery from “slow” inactivation could provide a molecular memory of recent cellular activity and help control CaV2 channel availability, electrical excitability, and neurotransmission in the seconds-to-minutes timeframe. PMID:26222492

  17. Effect of Bee Venom and Its Fractions on the Release of Pro-Inflammatory Cytokines in PMA-Differentiated U937 Cells Co-Stimulated with LPS

    PubMed Central

    Tusiimire, Jonans; Wallace, Jennifer; Woods, Nicola; Dufton, Mark J.; Parkinson, John A.; Abbott, Grainne; Clements, Carol J.; Young, Louise; Park, Jin Kyu; Jeon, Jong Woon; Ferro, Valerie A.; Watson, David G.

    2016-01-01

    The venom of Apis mellifera (honey bee) has been reported to play a role in immunotherapy, but existing evidence to support its immuno-modulatory claims is insufficient. Four fractions from whole bee venom (BV) were separated using medium pressure liquid chromatography. Their ability to induce the production of cytokines TNFα, IL-1β and IL-6 in phorbol-12-myristate-13-acetate (PMA)-treated U937 cells was assessed. The levels of the three cytokines produced by stimulation with the four fractions and crude BV without LPS were not significantly different from negative control values. However, co-stimulation of the cells with LPS and Fraction 4 (F-4) induced a 1.6-fold increase in TNF-α level (p < 0.05) compared to LPS alone. Likewise, LPS-induced IL-1β production was significantly synergised in the presence of F-1 (nine-fold), F-2 (six-fold), F-3 (four-fold) and F-4 (two-fold) fractions, but was only slightly enhanced with crude BV (1.5-fold) relative to LPS. Furthermore, the LPS-stimulated production of IL-6 was not significantly increased in cells co-treated with F-2 and F-3, but the organic fraction (F-4) showed an inhibitory effect (p < 0.05) on IL-6 production. The latter was elucidated by NMR spectroscopy and found to contain(Z)-9-eicosen-1-ol. The effects observed with the purified BV fractions were more marked than those obtained with the crude sample. PMID:27104574

  18. Effect of Bee Venom and Its Fractions on the Release of Pro-Inflammatory Cytokines in PMA-Differentiated U937 Cells Co-Stimulated with LPS.

    PubMed

    Tusiimire, Jonans; Wallace, Jennifer; Woods, Nicola; Dufton, Mark J; Parkinson, John A; Abbott, Grainne; Clements, Carol J; Young, Louise; Park, Jin Kyu; Jeon, Jong Woon; Ferro, Valerie A; Watson, David G

    2016-01-01

    The venom of Apis mellifera (honey bee) has been reported to play a role in immunotherapy, but existing evidence to support its immuno-modulatory claims is insufficient. Four fractions from whole bee venom (BV) were separated using medium pressure liquid chromatography. Their ability to induce the production of cytokines TNFα, IL-1β and IL-6 in phorbol-12-myristate-13-acetate (PMA)-treated U937 cells was assessed. The levels of the three cytokines produced by stimulation with the four fractions and crude BV without LPS were not significantly different from negative control values. However, co-stimulation of the cells with LPS and Fraction 4 (F-4) induced a 1.6-fold increase in TNF-α level (p < 0.05) compared to LPS alone. Likewise, LPS-induced IL-1β production was significantly synergised in the presence of F-1 (nine-fold), F-2 (six-fold), F-3 (four-fold) and F-4 (two-fold) fractions, but was only slightly enhanced with crude BV (1.5-fold) relative to LPS. Furthermore, the LPS-stimulated production of IL-6 was not significantly increased in cells co-treated with F-2 and F-3, but the organic fraction (F-4) showed an inhibitory effect (p < 0.05) on IL-6 production. The latter was elucidated by NMR spectroscopy and found to contain(Z)-9-eicosen-1-ol. The effects observed with the purified BV fractions were more marked than those obtained with the crude sample. PMID:27104574

  19. Phorbol myristate acetate receptors in human polymorphonuclear neutrophils

    SciTech Connect

    Nishihira, J.; O'Flaherty, J.T.

    1985-11-01

    Resting or phorbol myristate acetate (PMA)-pretreated neutrophils were disrupted by nitrogen cavitation and were fractionated on Percoll density gradients to identify the subcellular location of PMA receptors. Receptors were found in the cytoplasm of resting cells; neither primary nor secondary granules bound (/sup 3/H)PMA, and the few binding sites located in non-granule membrane fractions appeared to reflect cytosolic contamination. Contrastingly, PMA-pretreated cells lost cytosolic receptors; > 80% of PMA-binding sites were associated with non-granule membranes. Protein kinase C activity similarly shifted from cytosol to membranes after PMA treatment. Indeed, protein kinase C and PMA receptors co-sedimented on Percoll gradients, co-eluted from Ultragel AcA 44 columns loaded with neutrophil cytoplasm, and were identically influenced by various phospholipids. Finally, PMA, mezerein, diacylglycerol, and dialkylglycerol activated protein kinase C with potencies that paralleled their respective abilities to stimulate neutrophil aggregation responses and inhibit (/sup 3/H)PMA binding to whole cells or cytosol. These results fit a model of stimulus-response coupling wherein exogenous PMA or endogenous diacylglycerol solvate in cellular membranes. Cytosolic protein kinase C binds to the intramembranous ligand, forming an active, membrane-associated complex that phosphorylates nearby elements involved in triggering aggregation and other responses.

  20. Selective loss of PMA-stimulated expression of matrix metalloproteinase 1 in HaCaT keratinocytes is correlated with the inability to induce mitogen-activated protein family kinases.

    PubMed Central

    Sudbeck, B D; Baumann, P; Ryan, G J; Breitkopf, K; Nischt, R; Krieg, T; Mauch, C

    1999-01-01

    Many cell types, including fibroblasts and primary keratinocytes, increase matrix metalloproteinase 1 (MMP-1) production in response to agonists such as growth factors and phorbol esters. However, the spontaneously transformed human keratinocyte cell line HaCaT, although it increases MMP-1 production in response to epidermal growth factor (EGF), does not respond similarly to stimulation with PMA. This phenomenon occurs even though HaCaT cells remain proliferatively responsive to both agonists, suggesting a HaCaT-specific defect in a PMA-mediated signal transduction pathway. Using an inside-out approach to elucidate the source of this defect, we found that EGF, but not PMA, stimulated MMP-1 promoter activity in transiently transfected HaCaT keratinocytes. In addition, an assessment of fibroblast and HaCaT c-fos and c-jun gene expression after exposure to EGF and PMA showed that although both agonists increased the expression of c-fos and c-jun mRNA in fibroblasts, only EGF did so in HaCaT keratinocytes. Finally, we looked at the activation of mitogen-activated protein (MAP) family kinases after stimulation with EGF or PMA and found that both agonists increased the phosphorylation and activation of fibroblast extracellular signal-regulated protein kinase and c-Jun N-terminal kinase, but only EGF activated the same kinase activities in HaCaT cells. Further, the EGF-mediated increase in MMP-1 gene expression was inhibited by the MAP kinase/ERK kinase (MEK)-specific inhibitor PD98059 and the p38 kinase-specific inhibitor SB203580. Our evidence indicates that although HaCaT MAP kinases are functional, they are not properly regulated in response to the activation of protein kinase C, and that the defect that bars HaCaT MMP-1 expression in response to stimulation with PMA lies before MAP kinase activation. PMID:10085241

  1. 21 CFR 814.37 - PMA amendments and resubmitted PMA's.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false PMA amendments and resubmitted PMA's. 814.37... (CONTINUED) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES Premarket Approval Application (PMA) § 814.37 PMA amendments and resubmitted PMA's. (a) An applicant may amend a pending PMA or PMA...

  2. Acetic Acid Acts as a Volatile Signal To Stimulate Bacterial Biofilm Formation

    PubMed Central

    Chen, Yun; Gozzi, Kevin; Yan, Fang

    2015-01-01

    ABSTRACT Volatiles are small air-transmittable chemicals with diverse biological activities. In this study, we showed that volatiles produced by the bacterium Bacillus subtilis had a profound effect on biofilm formation of neighboring B. subtilis cells that grew in proximity but were physically separated. We further demonstrated that one such volatile, acetic acid, is particularly potent in stimulating biofilm formation. Multiple lines of genetic evidence based on B. subtilis mutants that are defective in either acetic acid production or transportation suggest that B. subtilis uses acetic acid as a metabolic signal to coordinate the timing of biofilm formation. Lastly, we investigated how B. subtilis cells sense and respond to acetic acid in regulating biofilm formation. We showed the possible involvement of three sets of genes (ywbHG, ysbAB, and yxaKC), all encoding putative holin-antiholin-like proteins, in cells responding to acetic acid and stimulating biofilm formation. All three sets of genes were induced by acetate. A mutant with a triple mutation of those genes showed a severe delay in biofilm formation, whereas a strain overexpressing ywbHG showed early and robust biofilm formation. Results of our studies suggest that B. subtilis and possibly other bacteria use acetic acid as a metabolic signal to regulate biofilm formation as well as a quorum-sensing-like airborne signal to coordinate the timing of biofilm formation by physically separated cells in the community. PMID:26060272

  3. Micromanipulation of adhesion of phorbol 12-myristate-13-acetate-stimulated T lymphocytes to planar membranes containing intercellular adhesion molecule-1.

    PubMed Central

    Tözeren, A; Mackie, L H; Lawrence, M B; Chan, P Y; Dustin, M L; Springer, T A

    1992-01-01

    This paper presents an analytical and experimental methodology to determine the physical strength of cell adhesion to a planar membrane containing one set of adhesion molecules. In particular, the T lymphocyte adhesion due to the interaction of the lymphocyte function associated molecule 1 on the surface of the cell, with its counter-receptor, intercellular adhesion molecule-1 (ICAM-1), on the planar membrane, was investigated. A micromanipulation method and mathematical analysis of cell deformation were used to determine (a) the area of conjugation between the cell and the substrate and (b) the energy that must be supplied to detach a unit area of the cell membrane from its substrate. T lymphocytes stimulated with phorbol 12-myristate-13-acetate (PMA) conjugated strongly with the planar membrane containing purified ICAM-1. The T lymphocytes attached to the planar membrane deviated occasionally from their round configuration by extending pseudopods but without changing the size of the contact area. These adherent cells were dramatically deformed and then detached when pulled away from the planar membrane by a micropipette. Detachment occurred by a gradual decrease in the radius of the contact area. The physical strength of adhesion between a PMA-stimulated T lymphocyte and a planar membrane containing 1,000 ICAM-1 molecules/micron 2 was comparable to the strength of adhesion between a cytotoxic T cell and its target cell. The comparison of the adhesive energy density, measured at constant cell shape, with the model predictions suggests that the physical strength of cell adhesion may increase significantly when the adhesion bonds in the contact area are immobilized by the actin cytoskeleton. Images FIGURE 2 FIGURE 4 FIGURE 5 FIGURE 8 FIGURE 9 PMID:1358239

  4. The stimulation of rat astrocytes with phorbol-12-myristate-13-acetate increases the proenkephalin mRNA: involvement of proto-oncogenes.

    PubMed

    Won, J S; Song, D K; Kim, Y H; Huh, S O; Suh, H W

    1998-03-01

    The effect of phorbol-12-myristate-13-acetate (PMA) on the regulation of proenkephalin (proENK) mRNA level, ENKCRE-2 or AP-1 DNA binding activity, and the mRNA and protein levels of proto-oncogenes (c-fos, fra-1, and c-jun) in primary cultured rat astrocytes were studied. The proENK mRNA level was elevated at 4 h after the treatment of PMA (2.5 microM) without altering the intracellular proENK protein level, and this increase was attenuated by pre-treatment with cycloheximide (CHX; 15 microM), a protein synthesis inhibitor. Both AP-1 and ENKCRE-2 DNA binding activities were markedly increased at 1-4 h by PMA treatment and these PMA-induced responses were inhibited by pre-treatment with CHX, showing that the increase of proENK mRNA level was well correlated with the AP-1 and ENKCRE-2 DNA binding activities. In contrast, although the phospho-CREBP level was also increased by PMA at 0.5-1 h, the pre-treatment with CHX further increased the PMA-induced phospho-CREBP level. In addition, PMA caused the induction of c-fos, c-jun and fra-1 mRNA level and, especially, PMA-induced increase of fra-1 mRNA level was further enhanced by CHX treatment at 4 h. Furthermore, western immunoblot assay showed that PMA caused induction of c-Fos, Fra-1, and c-Jun protein levels. PMA-induced increases of proto-oncoproteins levels were also inhibited by CHX treatment. The results suggest that newly synthesized AP-1 proteins, such as c-Fos, Fra-1, and c-Jun may play important roles in the regulation of PMA-induced proENK gene expression in cultured rat astrocytes. Phospho-CREB protein appears not to be involved in the regulation of PMA-induced proENK gene expression.

  5. 21 CFR 814.37 - PMA amendments and resubmitted PMA's.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... (CONTINUED) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES Premarket Approval Application (PMA) § 814... to amend a PMA or PMA supplement with any information regarding the device that is necessary for...

  6. 21 CFR 814.37 - PMA amendments and resubmitted PMA's.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... (CONTINUED) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES Premarket Approval Application (PMA) § 814... to amend a PMA or PMA supplement with any information regarding the device that is necessary for...

  7. Characterization of phorbol ester-stimulated serine phosphorylation of the human insulin receptor.

    PubMed Central

    Feener, E P; Shiba, T; Hu, K Q; Wilden, P A; White, M F; King, G L

    1994-01-01

    Phorbol 12-myristate 13-acetate (PMA)-stimulated phosphorylation of the human insulin receptor (IR) was characterized and compared in two cell types of different lineage: normal rat kidney epithelial (NRK) cells and Chinese hamster ovary (CHO) fibroblasts. PMA stimulation increased IR beta-subunit phosphorylation to 252 +/- 43 and 25- +/- 47% (+/- S.D.) of the unstimulated control in NRK and CHO cells respectively. Tryptic phosphopeptide analysis by Tricine/SDS/PAGE revealed significant differences in the PMA-stimulated phosphorylation of the IR in these two cell types. This phosphorylation of the IR was predominantly located in two tryptic phosphopeptides, and these phosphopeptides were absent in an IR mutant truncated by 43 C-terminal amino acids. The major PMA-stimulated tryptic phosphopeptide from in vivo-labelled CHO/IR was immunoprecipitated with an antibody against residues Ser1315 to Lys1329, and this precipitation was blocked with excess unlabelled peptide containing this sequence. Radiosequencing by manual Edman degradation revealed that this tryptic phosphopeptide was phosphorylated at Ser1315. This PMA-stimulated phosphorylation did not inhibit autophosphorylation of the IR in vivo. These results demonstrate that PMA-stimulated phosphorylation of the IR can exhibit significant differences when expressed in different cell types, and that Ser1315 is a major PMA-stimulated phosphorylation site on the human IR. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:7945263

  8. The effect of phorbol myristate acetate on the metabolism and ultrastructure of human alveolar macrophages.

    PubMed Central

    Hoidal, J. R.; Repine, J. E.; Beall, G. D.; Rasp, F. L.; White, J. G.

    1978-01-01

    In the present investigation we examined the influence of the surface-active agent phorbol myristate acetate (PMA) and opsonized heat-killed bacteria (HKB) on oxygen consumption, superoxide release, and glucose oxidation of human alveolar macrophages (AM). Both PMA and HKB produced a surge in oxygen consumption, superoxide release, and oxidation of 1-14C-glucose and 6-14C-glucose by human AM. Examination of AM by electron microscopy following stimulation by these two agents demonstrated membrane ruffling, loss of microvilli, and increased vacuolization in PMA-treated cells and phagocytic vacuoles containing bacteria in HKB-treated cells. The vacuolization produced by PMA-treated AM was much less striking than the vacuolization produced in PMA-treated leukocytes. The similarity in the metabolic and some of the physical responses of AM stimulated by PMA and HKB suggest that PMA may be a useful agent for evaluating cell-membrane-related events of phagocytosis in AM. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figures 9 and 10 Figures 11 and 12 PMID:207188

  9. Enhancement of human polymorphonuclear leukocyte adherence to plastic and endothelium by phorbol myristate acetate. Comparison with human C5a.

    PubMed Central

    Webster, R. O.; Wysolmerski, R. B.; Lagunoff, D.

    1986-01-01

    The adherence of circulating neutrophils to vascular endothelium represents a necessary step in the chemotactic emigration of neutrophils to extravascular inflammatory sites. Studies of neutrophil adherence induced by phorbol myristate acetate (PMA) were undertaken to determine the ability of a nonchemotactic neutrophil stimulus to provoke increased adherence. The authors found that the adherence of human neutrophils to plastic surfaces or confluent monolayers of endothelial cells is enhanced in a concentration-dependent fashion by exposure of neutrophils to PMA. The effect of PMA concentration (0.1-5.0 ng/ml) on increased neutrophil adherence parallels that observed for superoxide anion generation and release of lysosomal enzymes from specific granules. Whereas complement C5a-treated neutrophils exhibited a fourfold to fivefold increase in adherence to endothelial cells, PMA-treated neutrophils showed a 10-fold to 20-fold increase. The ability of PMA to cause increased neutrophil adherence to endothelium appeared to be directed primarily at the neutrophil. Pretreatment of neutrophils with PMA was as effective as coincubation in causing increased adherence to plastic surfaces or confluent cultured endothelial cells, but pretreatment of endothelial cells with PMA failed to promote neutrophil adherence. Alteration of neutrophil cytoskeletal structures by cytochalasin B treatment did not prevent subsequent PMA-stimulated neutrophil adherence. These results demonstrate that increased neutrophil adherence to surfaces can be induced by a nonchemotactic stimulus and that neutrophil adherence is independent of organized microfilaments. Images Figure 4 Figure 6 PMID:3789092

  10. Dual stimulus-dependent effect of Oenothera paradoxa extract on the respiratory burst in human leukocytes: suppressing for Escherichia coli and phorbol myristate acetate and stimulating for formyl-methionyl-leucyl-phenylalanine.

    PubMed

    Burzynska-Pedziwiatr, Izabela; Bukowiecka-Matusiak, Malgorzata; Wojcik, Marzena; Machala, Waldemar; Bienkiewicz, Malgorzata; Spolnik, Grzegorz; Danikiewicz, Witold; Wozniak, Lucyna Alicja

    2014-01-01

    Although a growing body of evidence suggests that plant polyphenols can modulate human immune responses, their simultaneous action on monocyte and neutrophil oxidative burst is currently poorly understood. Based on the hypothesis that various polyphenols contained in plant extracts might affect the oxidative burst of phagocytes, we evaluated the effects of ethanolic O. paradoxa extract polyphenols on monocyte and neutrophil oxidative burst in vitro activated by different stimuli, including opsonized bacteria E. coli, phorbol 12-myristate 13-acetate (PMA), and formyl-methionyl-leucyl-phenylalanine (fMLP). Samples were analyzed by the dihydrorhodamine flow cytometry assay. Our results showed that the extract repressed significantly and dose-dependently reactive oxygen species production in both cell types stimulated with E. coli and PMA (P < 0.05) and its inhibitory efficiency was stimulus- and cell-type-dependent. Interestingly, there was significant stimulatory effect of the extract on bursting phagocytes induced by fMLP (P < 0.05). Additionally, several flavonoids and phenolic compounds as well as penta-galloyl-β-(D)-glucose (PGG), the representative of hydrolyzable tannins, were identified in the 60% extract by high-performance liquid chromatography (HPLC) coupled to electrospray ionization in negative ion mode. In summary, the ethanolic O. paradoxa extract, rich in flavonoids and phenolic compounds, exhibits dual stimulus-dependent effect on the respiratory burst in human leukocytes; hence, it might affect immune responses in humans. PMID:25298860

  11. New Technique for Speciation of Uranium in Sediments Following Acetate-Stimulated Bioremediation

    SciTech Connect

    Not Available

    2011-06-22

    Acetate-stimulated bioremediation is a promising new technique for sequestering toxic uranium contamination from groundwater. The speciation of uranium in sediments after such bioremediation attempts remains unknown as a result of low uranium concentration, and is important to analyzing the stability of sequestered uranium. A new technique was developed for investigating the oxidation state and local molecular structure of uranium from field site sediments using X-Ray Absorption Spectroscopy (XAS), and was implemented at the site of a former uranium mill in Rifle, CO. Glass columns filled with bioactive Rifle sediments were deployed in wells in the contaminated Rifle aquifer and amended with a hexavalent uranium (U(VI)) stock solution to increase uranium concentration while maintaining field conditions. This sediment was harvested and XAS was utilized to analyze the oxidation state and local molecular structure of the uranium in sediment samples. Extended X-Ray Absorption Fine Structure (EXAFS) data was collected and compared to known uranium spectra to determine the local molecular structure of the uranium in the sediment. Fitting was used to determine that the field site sediments did not contain uraninite (UO{sub 2}), indicating that models based on bioreduction using pure bacterial cultures are not accurate for bioremediation in the field. Stability tests on the monomeric tetravalent uranium (U(IV)) produced by bioremediation are needed in order to assess the efficacy of acetate-stimulation bioremediation.

  12. Laboratory-scale bioaugmentation relieves acetate accumulation and stimulates methane production in stalled anaerobic digesters.

    PubMed

    Town, Jennifer R; Dumonceaux, Tim J

    2016-01-01

    An imbalance between acidogenic and methanogenic organisms during anaerobic digestion can result in increased accumulation of volatile fatty acids, decreased reactor pH, and inhibition of methane-producing Archaea. Most commonly the result of organic input overload or poor inoculum selection, these microbiological and biochemical changes severely hamper reactor performance, and there are a few tools available to facilitate reactor recovery. A small, stable consortium capable of catabolizing acetate and producing methane was propagated in vitro and evaluated as a potential bioaugmentation tool for stimulating methanogenesis in acidified reactors. Replicate laboratory-scale batch digesters were seeded with a combination of bioethanol stillage waste and a dairy manure inoculum previously observed to result in high volatile fatty acid accumulation and reactor failure. Experimental reactors were then amended with the acetoclastic consortium, and control reactors were amended with sterile culture media. Within 7 days, bioaugmented reactors had significantly reduced acetate accumulation and the proportion of methane in the biogas increased from 0.2 ± 0 to 74.4 ± 9.9 % while control reactors showed no significant reduction in acetate accumulation or increase in methane production. Organisms from the consortium were enumerated using specific quantitative PCR assays to evaluate their growth in the experimental reactors. While the abundance of hydrogenotrophic microorganisms remained stable during the recovery period, an acetoclastic methanogen phylogenetically similar to Methanosarcina sp. increased more than 100-fold and is hypothesized to be the primary contributor to reactor recovery. Genomic sequencing of this organism revealed genes related to the production of methane from acetate, hydrogen, and methanol.

  13. Laboratory-scale bioaugmentation relieves acetate accumulation and stimulates methane production in stalled anaerobic digesters.

    PubMed

    Town, Jennifer R; Dumonceaux, Tim J

    2016-01-01

    An imbalance between acidogenic and methanogenic organisms during anaerobic digestion can result in increased accumulation of volatile fatty acids, decreased reactor pH, and inhibition of methane-producing Archaea. Most commonly the result of organic input overload or poor inoculum selection, these microbiological and biochemical changes severely hamper reactor performance, and there are a few tools available to facilitate reactor recovery. A small, stable consortium capable of catabolizing acetate and producing methane was propagated in vitro and evaluated as a potential bioaugmentation tool for stimulating methanogenesis in acidified reactors. Replicate laboratory-scale batch digesters were seeded with a combination of bioethanol stillage waste and a dairy manure inoculum previously observed to result in high volatile fatty acid accumulation and reactor failure. Experimental reactors were then amended with the acetoclastic consortium, and control reactors were amended with sterile culture media. Within 7 days, bioaugmented reactors had significantly reduced acetate accumulation and the proportion of methane in the biogas increased from 0.2 ± 0 to 74.4 ± 9.9 % while control reactors showed no significant reduction in acetate accumulation or increase in methane production. Organisms from the consortium were enumerated using specific quantitative PCR assays to evaluate their growth in the experimental reactors. While the abundance of hydrogenotrophic microorganisms remained stable during the recovery period, an acetoclastic methanogen phylogenetically similar to Methanosarcina sp. increased more than 100-fold and is hypothesized to be the primary contributor to reactor recovery. Genomic sequencing of this organism revealed genes related to the production of methane from acetate, hydrogen, and methanol. PMID:26481626

  14. 21 CFR 814.37 - PMA amendments and resubmitted PMA's.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... (CONTINUED) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES Premarket Approval Application (PMA) § 814... information regarding the device that is necessary for FDA or the appropriate advisory committee to complete... applicant to amend a PMA or PMA supplement with any information regarding the device that is necessary...

  15. 21 CFR 814.37 - PMA amendments and resubmitted PMA's.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... (CONTINUED) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES Premarket Approval Application (PMA) § 814... information regarding the device that is necessary for FDA or the appropriate advisory committee to complete... applicant to amend a PMA or PMA supplement with any information regarding the device that is necessary...

  16. Effect of somatostatin and octreotide acetate on OP-CCK-stimulated exocrine secretion in the denervated canine pancreas.

    PubMed

    Garvin, P J; Burton, F R; Reese, J C; Dysarz, F A; Lingle, D; Niehoff, M L; Pandya, P K; Presti, M E

    1996-10-01

    Somatostatin and its analogue, octreotide acetate (Sandostatin), have been demonstrated to suppress exocrine secretion in a denervated canine pancreatic autograft model. To help define this inhibitory mechanism, the effect of these agents on cholecystokinin (CCK)-stimulated acinar cell secretion was evaluated. In vitro assessment evaluated the effect of somatostatin on octapeptide (OP)-CCK-stimulated amylase release of pancreatic tissue slices. In vivo assessment employed animals with pancreatic autografts and pancreaticocystostomies, evaluating the effect of a bolus intravenous injection of 100 micrograms of octreotide acetate on the basal and OP-CCK-stimulated (125 ng/kg/h) secretion of urinary (autograft) amylase and bicarbonate. Incubation of tissue slices with 0.16, 0.24, or 0.32 microgram/ml somatostatin had no significant effect on in vitro OP-CCK-simulated amylase release. Intravenous octreotide acetate resulted in a significant decrease in the basal rate of amylase secretion but had no significant effect on OP-CCK-stimulated autograft amylase or bicarbonate release. These studies demonstrate that octreotide acetate has an in vivo inhibitory effect on basal amylase release of pancreatic autografts but cannot counteract maximal stimulation with exogenous OP-CCK. Also, somatostatin does not inhibit OP-CCK-stimulated acinar cell secretion of pancreatic tissue slices. These results indicate that the exocrine inhibition produced by somatostatin analogues in the grafted pancreas occurs via an indirect mechanism.

  17. Activation of AMP-Activated Protein Kinase and Stimulation of Energy Metabolism by Acetic Acid in L6 Myotube Cells.

    PubMed

    Maruta, Hitomi; Yoshimura, Yukihiro; Araki, Aya; Kimoto, Masumi; Takahashi, Yoshitaka; Yamashita, Hiromi

    2016-01-01

    Previously, we found that orally administered acetic acid decreased lipogenesis in the liver and suppressed lipid accumulation in adipose tissue of Otsuka Long-Evans Tokushima Fatty rats, which exhibit hyperglycemic obesity with hyperinsulinemia and insulin resistance. Administered acetic acid led to increased phosphorylation of AMP-activated protein kinase (AMPK) in both liver and skeletal muscle cells, and increased transcripts of myoglobin and glucose transporter 4 (GLUT4) genes in skeletal muscle of the rats. It was suggested that acetic acid improved the lipid metabolism in skeletal muscles. In this study, we examined the activation of AMPK and the stimulation of GLUT4 and myoglobin expression by acetic acid in skeletal muscle cells to clarify the physiological function of acetic acid in skeletal muscle cells. Acetic acid added to culture medium was taken up rapidly by L6 cells, and AMPK was phosphorylated upon treatment with acetic acid. We observed increased gene and protein expression of GLUT4 and myoglobin. Uptake of glucose and fatty acids by L6 cells were increased, while triglyceride accumulation was lower in treated cells compared to untreated cells. Furthermore, treated cells also showed increased gene and protein expression of myocyte enhancer factor 2A (MEF2A), which is a well-known transcription factor involved in the expression of myoglobin and GLUT4 genes. These results indicate that acetic acid enhances glucose uptake and fatty acid metabolism through the activation of AMPK, and increases expression of GLUT4 and myoglobin.

  18. Activation of AMP-Activated Protein Kinase and Stimulation of Energy Metabolism by Acetic Acid in L6 Myotube Cells.

    PubMed

    Maruta, Hitomi; Yoshimura, Yukihiro; Araki, Aya; Kimoto, Masumi; Takahashi, Yoshitaka; Yamashita, Hiromi

    2016-01-01

    Previously, we found that orally administered acetic acid decreased lipogenesis in the liver and suppressed lipid accumulation in adipose tissue of Otsuka Long-Evans Tokushima Fatty rats, which exhibit hyperglycemic obesity with hyperinsulinemia and insulin resistance. Administered acetic acid led to increased phosphorylation of AMP-activated protein kinase (AMPK) in both liver and skeletal muscle cells, and increased transcripts of myoglobin and glucose transporter 4 (GLUT4) genes in skeletal muscle of the rats. It was suggested that acetic acid improved the lipid metabolism in skeletal muscles. In this study, we examined the activation of AMPK and the stimulation of GLUT4 and myoglobin expression by acetic acid in skeletal muscle cells to clarify the physiological function of acetic acid in skeletal muscle cells. Acetic acid added to culture medium was taken up rapidly by L6 cells, and AMPK was phosphorylated upon treatment with acetic acid. We observed increased gene and protein expression of GLUT4 and myoglobin. Uptake of glucose and fatty acids by L6 cells were increased, while triglyceride accumulation was lower in treated cells compared to untreated cells. Furthermore, treated cells also showed increased gene and protein expression of myocyte enhancer factor 2A (MEF2A), which is a well-known transcription factor involved in the expression of myoglobin and GLUT4 genes. These results indicate that acetic acid enhances glucose uptake and fatty acid metabolism through the activation of AMPK, and increases expression of GLUT4 and myoglobin. PMID:27348124

  19. Activation of AMP-Activated Protein Kinase and Stimulation of Energy Metabolism by Acetic Acid in L6 Myotube Cells

    PubMed Central

    Maruta, Hitomi; Yoshimura, Yukihiro; Araki, Aya; Kimoto, Masumi; Takahashi, Yoshitaka; Yamashita, Hiromi

    2016-01-01

    Previously, we found that orally administered acetic acid decreased lipogenesis in the liver and suppressed lipid accumulation in adipose tissue of Otsuka Long-Evans Tokushima Fatty rats, which exhibit hyperglycemic obesity with hyperinsulinemia and insulin resistance. Administered acetic acid led to increased phosphorylation of AMP-activated protein kinase (AMPK) in both liver and skeletal muscle cells, and increased transcripts of myoglobin and glucose transporter 4 (GLUT4) genes in skeletal muscle of the rats. It was suggested that acetic acid improved the lipid metabolism in skeletal muscles. In this study, we examined the activation of AMPK and the stimulation of GLUT4 and myoglobin expression by acetic acid in skeletal muscle cells to clarify the physiological function of acetic acid in skeletal muscle cells. Acetic acid added to culture medium was taken up rapidly by L6 cells, and AMPK was phosphorylated upon treatment with acetic acid. We observed increased gene and protein expression of GLUT4 and myoglobin. Uptake of glucose and fatty acids by L6 cells were increased, while triglyceride accumulation was lower in treated cells compared to untreated cells. Furthermore, treated cells also showed increased gene and protein expression of myocyte enhancer factor 2A (MEF2A), which is a well-known transcription factor involved in the expression of myoglobin and GLUT4 genes. These results indicate that acetic acid enhances glucose uptake and fatty acid metabolism through the activation of AMPK, and increases expression of GLUT4 and myoglobin. PMID:27348124

  20. 21 CFR 882.5860 - Implanted neuromuscular stimulator.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) Date PMA or notice of completion of PDP is required. A PMA or notice of completion of a PDP for a.... Any other implanted neuromuscular stimulator shall have an approved PMA or declared completed PDP...

  1. Phorbol myristate acetate inhibits anti-IgM-mediated signaling in resting B cells.

    PubMed Central

    Mizuguchi, J; Beaven, M A; Li, J H; Paul, W E

    1986-01-01

    Cross-linking the membrane immunoglobulins of resting B cells leads to activation as judged by increased inositol phospholipid metabolism, intracellular free calcium concentration ([Ca2+]i), and cell volume. Such activated B cells enter S phase in the presence of B-cell stimulatory factor 1. Phorbol myristate acetate (PMA) is a potent inhibitor of anti-IgM- and anti-IgD-stimulated B-cell responses. In B cells concentrations of PMA ranging from 0.1 to 100 ng/ml completely inhibit anti-IgM-stimulated DNA synthesis and block anti-IgM-stimulated increases in inositol phospholipid metabolism and in [Ca2+]i. Preincubation periods as short as 4 min block these effects although longer preincubations are somewhat more effective in inhibiting increases in [Ca2+]i. Preincubation with PMA for 1.5 hr does not diminish expression of membrane IgM. This strongly suggests that PMA inhibits responses of resting B cells to anti-IgM by interrupting signal transmission rather than by diminishing cross-linking of membrane immunoglobulin on B cells. In contrast to resting B cells, B cells activated in vitro for 29 hr show enhanced responses to anti-IgM in the presence of PMA. PMID:3086884

  2. Sodium acetate decreases phosphorylation of hormone sensitive lipase in isoproterenol-stimulated 3T3-L1 mature adipocytes

    PubMed Central

    Aberdein, Nicola; Schweizer, Michael; Ball, Derek

    2014-01-01

    Lipolysis, the process of hydrolysis of stored triacylglycerol into glycerol and non-esterified fatty acids (NEFA), is reported to be reduced by short chain fatty acids (SCFA) but the mechanism of this inhibition is poorly understood. The aim of this study was to measure the phosphorylation at serine residue 563 of hormone sensitive lipase with and without exposure to sodium acetate. Using the 3T3-L1 cell line, we identified that stimulating the cells with isoproterenol increased phosphorylated hormone sensitive lipase (pHSL) expression by 60% compared with the basal state. In the presence of the SCFA acetate in stimulated cells, pHSL decreased by 15% compared with stimulated cells alone. These results were mirrored by the NEFA release from stimulated cells that had significantly decreased in the presence of sodium acetate after 60 min (from 0.53 µmol mg−1 protein to 0.41 µmol mg−1 protein, respectively, P = 0.004); and 180 min (1.73 µmol mg−1 protein to 1.13 µmol mg−1 protein, P = 0.020); however, treatment had no effect on glycerol release (P = 0.109). In conclusion, exposure to 4 mM acetate reduced the level of phosphorylation of HSL(SER563) in mature 3T3-L1 adipocytes and led to a significant reduction in NEFA release, although glycerol release was not affected. PMID:24719785

  3. Activation of resting T cells: distinct roles of intact accessory cells, phorbol myristate acetate and interleukin 1

    SciTech Connect

    Davis, L.; Lipsky, P.E.

    1986-03-05

    The accessory cell (AC) signals involved in the activation of resting guinea pig T lymphocytes stimulated with mitogen (PHA), or the calcium ionophore, ionomycin (Ion) were examined. Activation of T cells was assessed by cell cycle analysis after acridine orange staining and /sup 3/H-thymidine incorporation. PHA-stimulated T cells depleted of all AC were unable to respond in the presence of phorbol myristate acetate (PMA), and/or interleukin 1 (IL 1). With suboptimal numbers of AC, PMA greatly augmented the number of T cells activated by PHA to enter and progress through the cell cycle, but only when present during the first few hours of culture. By contrast, IL 1 had little effect on the number of cells entering the cell cycle, although it enhanced S phase entry of the activated cells. IL 1 augmented DNA synthesis when added initially or later in culture. In contrast to the effects noted with PHA, PMA promoted activation and DNA synthesis of the majority of Ion stimulated cells in the complete absence of AC. IL 1 alone could not support Ion induced T cell activation although it enhanced T cell DNA synthesis in cultures stimulated by PMA and Ion. These studies indicate that intact AC, IL 1 and PMA-like signals play distinct roles in the progression of T cells through the initial cell cycle. Stimulation by Ion requires only PMA whereas PHA responses require intact AC and can be amplified by PMA. The major effect of IL 1 is to promote S phase entry of activated T cells.

  4. High temperature stimulates acetic acid accumulation and enhances the growth inhibition and ethanol production by Saccharomyces cerevisiae under fermenting conditions.

    PubMed

    Woo, Ji-Min; Yang, Kyung-Mi; Kim, Sae-Um; Blank, Lars M; Park, Jin-Byung

    2014-07-01

    Cellular responses of Saccharomyces cerevisiae to high temperatures of up to 42 °C during ethanol fermentation at a high glucose concentration (i.e., 100 g/L) were investigated. Increased temperature correlated with stimulated glucose uptake to produce not only the thermal protectant glycerol but also ethanol and acetic acid. Carbon flux into the tricarboxylic acid (TCA) cycle correlated positively with cultivation temperature. These results indicate that the increased demand for energy (in the form of ATP), most likely caused by multiple stressors, including heat, acetic acid, and ethanol, was matched by both the fermentation and respiration pathways. Notably, acetic acid production was substantially stimulated compared to that of other metabolites during growth at increased temperature. The acetic acid produced in addition to ethanol seemed to subsequently result in adverse effects, leading to increased production of reactive oxygen species. This, in turn, appeared to cause the specific growth rate, and glucose uptake rate reduced leading to a decrease of the specific ethanol production rate far before glucose depletion. These results suggest that adverse effects from heat, acetic acid, ethanol, and oxidative stressors are synergistic, resulting in a decrease of the specific growth rate and ethanol production rate and, hence, are major determinants of cell stability and ethanol fermentation performance of S. cerevisiae at high temperatures. The results are discussed in the context of possible applications.

  5. Vagal nerve stimulation reverses aberrant dopamine system function in the methylazoxymethanol acetate rodent model of schizophrenia.

    PubMed

    Perez, Stephanie M; Carreno, Flavia R; Frazer, Alan; Lodge, Daniel J

    2014-07-01

    Vagal nerve stimulation (VNS) is an alternative therapy for epilepsy and treatment refractory depression. Here we examine VNS as a potential therapy for the treatment of schizophrenia in the methylozoxymethanol acetate (MAM) rodent model of the disease. We have previously demonstrated that hyperactivity within ventral regions of the hippocampus (vHipp) drives the dopamine system dysregulation in this model. Moreover, by targeting the vHipp directly, we can reverse aberrant dopamine system function and associated behaviors in the MAM model. Although the central effects of VNS have not been completely delineated, positron emission topographic measurements of cerebral blood flow in humans have consistently reported that VNS stimulation induces bilateral decreases in hippocampal activity. Based on our previous observations, we performed in vivo extracellular electrophysiological recordings in MAM- and saline-treated rats to evaluate the effect of chronic (2 week) VNS treatment on the activity of putative vHipp pyramidal neurons, as well as downstream dopamine neuron activity in the ventral tegmental area. Here we demonstrate that chronic VNS was able to reverse both vHipp hyperactivity and aberrant mesolimbic dopamine neuron function in the MAM model of schizophrenia. Additionally, VNS reversed a behavioral correlate of the positive symptoms of schizophrenia. Because current therapies for schizophrenia are far from adequate, with a large number of patients discontinuing treatment due to low efficacy or intolerable side effects, it is important to explore alternative nonpharmacological treatments. These data provide the first preclinical evidence that VNS may be a possible alternative therapeutic approach for the treatment of schizophrenia.

  6. Regulation of plasminogen activator in 3T3 cells: effect of phorbol myristate acetate on subcellular distribution and molecular weight

    PubMed Central

    1981-01-01

    The tumor promoter, phorbol myristate acetate (PMA), stimulates plasminogen activator production and extracellular release in confluent Swiss 3T3 cells. Coordinated with the increased extracellular release is a redistribution of the activity into plasma membrane-enriched fractions and a shift in the predominant molecular weight species from 75,000 to 49,000 daltons. The evidence suggests that PMA induces the formation of the 49,000 dalton species which is preferentially located in plasma membrane-enriched fractions. PMID:7197280

  7. Effects of phorbol 12-myristate 13-acetate on triglyceride and cholesteryl ester synthesis in cultured coronary smooth muscle cells and macrophages.

    PubMed

    Moinat, M; Chevey, J M; Muzzin, P; Giacobino, J P; Kossovsky, M

    1990-02-01

    In cultured pig coronary smooth muscle cells phorbol 12-myristate 13-acetate (PMA) stimulated the conversion of [4-14C]cholesterol into cholesteryl esters and the incorporation of [2-3H]glycerol into triglycerides 6.4- and 4.5-fold, respectively. The maximal effects occurred after 3 h of treatment and there was a return to basal values after 72 h. In the presence of 400 microM oleic acid, PMA stimulated the conversion of [4-14C]cholesterol into cholesteryl esters and that of [2-3H]glycerol into triglycerides 5.3- and 2.3-fold, respectively. The stimulatory effects were more sustained (still significant after 72 h) and their maxima were delayed (peaks after 24 h). PMA was also found to increase 2-fold the amount of triglyceride that accumulated in the cells in the presence of oleic acid after 24 h. In macrophages IC-21, the effects of PMA were observed only in the presence of oleic acid. They consisted of a 1.9-fold stimulation in the conversion of [4-14C]cholesterol into cholesteryl esters after 72 h and of a 1.7-fold stimulation in the incorporation of [2-3H]glycerol into triglycerides after 24 h. PMA also increased the amount of triglyceride that accumulated in the cells 1.9-fold after 72 h. It is concluded that PMA, and possibly growth factors, may promote lipid storage in smooth muscle cells and that fatty acids favor long lasting effects of PMA in smooth muscle cells and are necessary for any effect of PMA in macrophages. PMID:2324651

  8. High-density PhyloChip profiling of stimulated aquifer microbial communities reveals a complex response to acetate amendment

    SciTech Connect

    Handley, Kim M.; Wrighton, Kelly C.; Piceno, Yvette M.; Andersen, Gary L.; DeSantis, Todd Z.; Williams, Kenneth H.; Wilkins, Michael J.; N'Guessan, A. Lucie; Peacock, Aaron; Bargar, John; Long, Philip E.; Banfield, Jillian F.

    2012-04-13

    There is increasing interest in harnessing the functional capacities of indigenous microbial communities to transform and remediate a wide range of environmental contaminants. Information about which community members respond to stimulation can guide the interpretation and development of remediation approaches. To comprehensively determine community membership and abundance patterns among a suite of samples associated with uranium bioremediation experiments we employed a high-density microarray (PhyloChip). Samples were unstimulated, naturally reducing, or collected during Fe(III) (early) and sulfate reduction (late biostimulation) from an acetate re-amended/amended aquifer in Rifle, Colorado, and from laboratory experiments using field-collected materials. Deep community sampling with PhyloChip identified hundreds-to-thousands of operational taxonomic units (OTUs) present during amendment, and revealed close similarity among highly enriched taxa from drill-core and groundwater well-deployed column sediment. Overall, phylogenetic data suggested stimulated community membership was most affected by a carryover effect between annual stimulation events. Nevertheless, OTUs within the Fe(III)- and sulfate-reducing lineages, Desulfuromonadales and Desulfobacterales, were repeatedly stimulated. Less consistent, co-enriched taxa represented additional lineages associated with Fe(III) and sulfate reduction (for example, Desulfovibrionales; Syntrophobacterales; Peptococcaceae) and autotrophic sulfur oxidation (Sulfurovum; Campylobacterales). These data imply complex membership among highly stimulated taxa, and by inference biogeochemical responses to acetate, a non-fermentable substrate.

  9. High-density PhyloChip profiling of stimulated aquifer microbial communities reveals a complex response to acetate amendment.

    PubMed

    Handley, Kim M; Wrighton, Kelly C; Piceno, Yvette M; Andersen, Gary L; DeSantis, Todd Z; Williams, Kenneth H; Wilkins, Michael J; N'Guessan, A Lucie; Peacock, Aaron; Bargar, John; Long, Philip E; Banfield, Jillian F

    2012-07-01

    There is increasing interest in harnessing the functional capacities of indigenous microbial communities to transform and remediate a wide range of environmental contaminants. Information about which community members respond to stimulation can guide the interpretation and development of remediation approaches. To comprehensively determine community membership and abundance patterns among a suite of samples associated with uranium bioremediation experiments, we employed a high-density microarray (PhyloChip). Samples were unstimulated, naturally reducing, or collected during Fe(III) (early) and sulfate reduction (late biostimulation) from an acetate re-amended/amended aquifer in Rifle, Colorado, and from laboratory experiments using field-collected materials. Deep community sampling with PhyloChip identified hundreds-to-thousands of operational taxonomic units (OTUs) present during amendment, and revealed close similarity among highly enriched taxa from drill core and groundwater well-deployed column sediment. Overall, phylogenetic data suggested that stimulated community membership was most affected by a carryover effect between annual stimulation events. Nevertheless, OTUs within the Fe(III)- and sulfate-reducing lineages, Desulfuromonadales and Desulfobacterales, were repeatedly stimulated. Less consistent, co-enriched taxa represented additional lineages associated with Fe(III) and sulfate reduction (e.g. Desulfovibrionales; Syntrophobacterales; Peptococcaceae) and autotrophic sulfur oxidation (Sulfurovum; Campylobacterales). Data implies complex membership among highly stimulated taxa and, by inference, biogeochemical responses to acetate, a nonfermentable substrate.

  10. Apigenin inhibits PMA-induced expression of pro-inflammatory cytokines and AP-1 factors in A549 cells.

    PubMed

    Patil, Rajeshwari H; Babu, R L; Naveen Kumar, M; Kiran Kumar, K M; Hegde, Shubha M; Ramesh, Govindarajan T; Chidananda Sharma, S

    2015-05-01

    Acute and chronic alveolar or bronchial inflammation is thought to be central to the pathogenesis of many respiratory disorders. Cytokines and granulocyte macrophage colony-stimulating factors (GM-CSF) play an important role in chronic inflammation. Activator protein-1 (AP-1) the superfamily of transcription factors is involved in proliferation, differentiation, apoptosis, and transformation including inflammation. Understanding the function and regulation of proinflammatory factors involved in inflammation may provide the novel therapeutic strategies in the treatment of inflammatory diseases. Our aim of the present study is to investigate the pro-inflammatory cytokines and pattern of AP-1 factors expressed during activation of lung adenocarcinoma A549 cells by Phorbol-12-myristate-13-acetate (PMA) and to understand the anti-inflammatory effect of apigenin. A549 cells were treated with and without PMA or apigenin, and the cell viability was assessed by MTT assay. Expressions of inflammatory mediators and different AP-1 factors were analyzed by semi-quantitative RT-PCR. IL-6 protein secreted was analyzed by ELISA, and expressions of IL-1β, c-Jun, and c-Fos proteins were analyzed by Western blotting. Activation of A549 cells by PMA, induced the expression of pro-inflammatory cytokine (IL-1β, IL-2, IL-6, IL-8, and TNF-α) mRNAs and secretion of IL-6 and the expression of specific AP-1 factors (c-Jun, c-Fos, and Fra-1). Treatment of cells with apigenin, significantly inhibited PMA-stimulated mRNA expression of above pro-inflammatory cytokines, AP-1 factors, cyclooxygenase-2, and secretion of IL-6 protein. Results suggested that the AP-1 factors may be involved in inflammation and apigenin has anti-inflammatory effect, which may be useful for therapeutic management of lung inflammatory diseases. PMID:25666088

  11. Orostachys japonicus Inhibits Expression of the TLR4, NOD2, iNOS, and COX-2 Genes in LPS-Stimulated Human PMA-Differentiated THP-1 Cells by Inhibiting NF-κB and MAPK Activation

    PubMed Central

    Woo, Hong-Jung; Kim, Youngchul

    2015-01-01

    Orostachys japonicus is traditionally used as an inflammatory agent. In this report, we investigated the effects of O. japonicus extract on the expression of genes encoding pathogen-recognition receptors (TLR2, TLR4, NOD1, and NOD2) and proinflammatory factors (iNOS, COX-2, and cytokines) in LPS-stimulated PMA-differentiated THP-1 cells and the NF-κB and MAPK pathways. O. japonicus induced toxicity at high concentrations but had no effect at concentrations lower than 25 μg/mL. O. japonicus inhibited LPS-induced TLR4 and NOD2 mRNA levels, suppressed LPS-induced iNOS and COX-2 transcription and translocation, and downregulated LPS-induced proinflammatory cytokine (IL-1β, IL-6, IL-8, and TNF-α) mRNA levels. In addition, O. japonicus inhibited LPS-induced NF-κB activation and IκBα degradation and suppressed LPS-induced JNK, p38 MAPK, and ERK phosphorylation. Overall, our results demonstrate that the anti-inflammatory effects of O. japonicus are mediated by suppression of NF-κB and MAPK signaling, resulting in reduced TLR4, NOD2, iNOS, and COX-2 expression and inhibition of inflammatory cytokine expression. PMID:25810745

  12. Regulation of lymphotoxin production by the p21ras-raf-MEK-ERK cascade in PHA/PMA-stimulated Jurkat cells.

    PubMed

    Li, Y Q; Hii, C S; Costabile, M; Goh, D; Der, C J; Ferrante, A

    1999-03-15

    Although the production of lymphotoxin (LT) from activated Th1 lymphocytes has been reported extensively, the intracellular signaling mechanisms that regulate this T cell function remain totally undefined. We have examined whether the p21ras-raf-1-mitogen-activated protein kinase/extracellular signal-regulated protein kinase (ERK) kinase (MEK)-ERK cascade plays a role in regulating the production of LT, because the activity of these signaling molecules is up-regulated in activated T lymphocytes. Transfection of Jurkat leukemic T cells with a dominant negative mutant of p21ras (ras17N or ras15A), raf-1 (raf 1-130), or ERK1 (Erk1-K71R) resulted in the suppression of the mitogen/phorbol ester-stimulated production/secretion of LT. This suppression was accompanied by a parallel inhibition of mitogen-stimulated ERK activation. The selective antagonist of MEK1 activation, PD98059, also attenuated the mitogen-stimulated or anti-CD3 Ab and phorbol ester-stimulated production of LT from Jurkat cells or peripheral blood T lymphocytes. This study provides, for the first time, direct evidence that the p21ras-raf-MEK-ERK cascade plays a vital role in regulating the production of LT.

  13. Tumor-promoting phorbol ester stimulates tyrosine phosphorylation in U-937 monocytes.

    PubMed Central

    Grunberger, G; Zick, Y; Taylor, S I; Gorden, P

    1984-01-01

    Solubilized lectin-purified extracts from human monocyte-like cells (U-937) and freshly isolated human mononuclear cells preincubated in the presence of phorbol 12-myristate 13-acetate (PMA) stimulated phosphorylation of synthetic tyrosine-containing polymers and of casein. Tyrosine phosphorylation was confirmed by phospho amino acid analysis. PMA stimulated phosphorylation of exogenous substrates in a time- and concentration-dependent manner. This phosphorylation reaction did not require addition of phospholipid, diolein, or calcium. Biologically inactive phorbol compounds did not stimulate phosphorylation in this system. In addition, PMA enhanced phosphorylation of a Mr approximately equal to 140,000 protein as well as several other endogenous proteins in the U-937 extracts. PMA treatment stimulated predominantly phosphorylation on tyrosine residues of the Mr 140,000 protein. Tyrosine phosphorylation, typical of growth-promoting peptides such as insulin or epidermal growth factor, is believed to play a role in regulating normal and disordered cellular growth and proliferation. The demonstration of PMA-stimulated tyrosine phosphorylation might provide a clue to the mechanism of cellular differentiation and proliferation induced by the tumor promoter. Images PMID:6201862

  14. Insulin and phorbol ester stimulate conductive Na/sup +/ transport through a common pathway

    SciTech Connect

    Civan, M.M.; Peterson-Yantorno, K.; O'Brien, T.G.

    1988-02-01

    Insulin stimulates Na/sup +/ transport across frog skin, toad urinary bladder, and the distal renal nephron. This stimulation reflects an increase in apical membrane Na/sup +/ permeability and a stimulation of the basolateral membrane Na,K-exchange pump. Considerable indirect evidence has suggested that the apical natriferic effect of insulin is mediated by activation of protein kinase C. However, no direct information has been available documenting that insulin and protein kinase C indeed share a common pathway in stimulating Na/sup +/ transport across frog skin. In the present work, the authors have studied the interaction of insulin and phorbol 12-myristate 13-acetate (PMA), a documented activator of protein kinase C. Preincubation of skins with 1,2-dioctanoylglycerol, another activator of protein kinase C, increases baseline Na/sup +/ transport and reduces the subsequent natriferic response to PMA. Preincubation with PMA markedly reduces the subsequent natriferic action of insulin. This effect does not appear to primarily reflect PMA-induced internalization of insulin receptors. The insulin receptors are localized on the basolateral surface of frog skin, but the application of PMA to this surface is much less effective than mucosal treatment in reducing the response to insulin. The current results provide documentation that insulin and protein kinase C share a common pathway in stimulating Na/sup +/ transport across frog skin. The data are consistent with the concept that the natriferic effect of insulin on frog skin is, at least in part, mediated by activation of protein kinase C.

  15. High-throughput Protease Activity Cytometry Reveals Dose-dependent Heterogeneity in PMA-mediated ADAM17 Activation†

    PubMed Central

    Wu, Lidan; Claas, Allison M.; Sarkar, Aniruddh; Lauffenburger, Douglas A.; Han, Jongyoon

    2015-01-01

    As key components of autocrine signaling, pericellular proteases, A Disintegrin and Metalloproteinases (ADAMs) in particular, are known to impact the microenvironment of individual cells and have significant implications in various pathological situations including cancer, inflammatory and vascular diseases.1-3 There is great incentive to develop a high-throughput platform for single-cell measurement of pericellular protease activity, as it is essential for studying the heterogeneity of protease response and the corresponding cell behavioral consequences. In this work, we developed a microfluidic platform to simultaneously monitor protease activity of many single cells in a time-dependent manner. This platform isolates individual microwells rapidly on demand and thus allows single-cell activity measurement of both cell-surface and secreted proteases by confining individual cells with diffusive FRET-based substrates. With this platform, we observed dose-dependent heterogeneous protease activation of HepG2 cells treated with phorbol 12-myristate 13-acetate (PMA). To study the temporal behavior of PMA-induced protease response, we monitored the pericellular protease activity of the same single cells during three different time periods and revealed the diversity in the dynamic patterns of single-cell protease activity profile upon PMA stimulation. The unique temporal information of single-cell protease response can help unveil the complicated functional role of pericellular proteases. PMID:25832727

  16. A requirement for extracellular signal-regulated kinase (ERK) function in the activation of AP-1 by Ha-Ras, phorbol 12-myristate 13-acetate, and serum.

    PubMed Central

    Frost, J A; Geppert, T D; Cobb, M H; Feramisco, J R

    1994-01-01

    The role of ERK-1 and ERK-2 in wild-type (wt) Ha-Ras, phorbol 12-myristate 13-acetate (PMA), and serum-induced AP-1 activity was studied. Microinjection of ERK-specific substrate peptides inhibited the induction of AP-1 activity by all three stimuli, whereas a control peptide had no effect. By using eukaryotic expression constructs encoding wt ERK-1 and kinase-deficient mutants of ERKs 1 and 2, it was found that ERK-1 and ERK-2 activities are required for AP-1 activation stimulated by either wt Ha-Ras, PMA, or serum. Overexpression of ERK-1 augmented wt Ha-Ras stimulation of AP-1, while having no effect upon PMA or serum stimulation. Overexpression of either kinase-deficient ERK-1 or kinase-deficient ERK-2 partially inhibited AP-1 activation by wt Ha-Ras but had no effect on PMA or serum-induced activation. Coexpression of both interfering mutants abolished AP-1 induction by wt Ha-Ras, PMA, or serum. We conclude that ERKs are necessary components in the pathway leading to the activation of AP-1 stimulated by these agents. Images PMID:8170999

  17. The choice of phorbol 12-myristate 13-acetate differentiation protocol influences the response of THP-1 macrophages to a pro-inflammatory stimulus.

    PubMed

    Lund, Maria E; To, Joyce; O'Brien, Bronwyn A; Donnelly, Sheila

    2016-03-01

    The human monocytic cell line, THP-1, is the most widely used model for primary human monocytes/macrophages. This is because, following differentiation using phorbol 12-myristate 13-acetate (PMA), THP-1 cells acquire a macrophage-like phenotype, which mimics, in many respects, primary human macrophages. Despite the widespread use of THP-1 cells in studies elucidating macrophage responses to inflammatory stimuli, as well as the development and screening of potential therapeutics, there is currently no standardised protocol for the reliable differentiation of THP-1 monocytes to a macrophage phenotype using PMA. Consequently, reports using THP-1 cells have demonstrated significant phenotypic and functional differences between resultant THP-1 macrophage populations, which are largely attributable to the varying PMA differentiation methods used. Thus, to guarantee consistency and reproducibility between studies, and to ensure the relevance of THP-1 cells as an appropriate model for primary human macrophages, it is crucial to develop a standardised protocol for the differentiation of THP-1 macrophages. Accordingly, we compared the function and phenotype of THP-1 macrophages generated using the range of published PMA differentiation protocols, specifically in response to the pro-inflammatory stimulus, lipopolysaccharide (LPS). Our results demonstrated that the function of the resultant THP-1 macrophage populations, as determined by tumour necrosis factor (TNF) secretion in response to LPS stimulation, varied significantly, and was dependent upon the concentration of PMA used to stimulate the differentiation of monocytes, and the period of rest following PMA exposure. These data indicate that exposure of monocytic THP-1 cells to 25 nM PMA over 48 h, followed by a recovery period of 24h in culture in the absence of PMA, was the optimal protocol for the differentiation of THP-1 cells.

  18. Signals involved in T cell activation. I. Phorbol esters enhance responsiveness but cannot replace intact accessory cells in the induction of mitogen-stimulated T cell proliferation

    SciTech Connect

    Davis, L.; Lipsky, P.E.

    1985-11-01

    The role of accessory cells (AC) in the initiation of mitogen-induced T cell proliferation was examined by comparing the effect of intact macrophages (M phi) with that of 4-..beta..-phorbol 12-myristate 13-acetate (PMA). In high-density cultures, purified guinea pig T cells failed to proliferate in response to stimulation with phytohemagglutinin (PHA), concanavalin A (Con A), or PMA alone. The addition of M phi to PHA or Con A but not PMA-stimulated cultures restored T cell proliferation. The addition of PMA to high-density T cell cultures stimulated with PHA or Con A also permitted (/sup 3/H)thymidine incorporation, but was less effective than intact M phi in this regard. This action of PMA was dependent on the small number of Ac contaminating the T cell cultures as evidenced by the finding that PMA could not support mitogen responsiveness of T cells that had been depleted of Ia-bearing cells by panning, even when these cells were cultured at high density. A low-density culture system was used to examine in greater detail the possibility that PMA could completely substitute for M phi in promoting T cells activation. In low-density cultures, mitogen-induced T cell proliferation required intact M phi. These results support a model of T cell activation in which AC play at least two distinct roles. The initiation of the response requires a signal conveyed by an intact M phi, which cannot be provided by either a M phi supernatant factor or PMA. The response can be amplified by additional M phi or M phi supernatant factors. PMA can substitute for M phi in this regard and can provide the signal necessary for amplification of T cell proliferation supported by small numbers of intact AC.

  19. Phorbol ester phorbol-12-myristate-13-acetate promotes anchorage-independent growth and survival of melanomas through MEK-independent activation of ERK1/2

    SciTech Connect

    Jorgensen, Kjersti; Skrede, Martina; Cruciani, Veronique; Mikalsen, Svein-Ole; Slipicevic, Ana; Florenes, Vivi Ann . E-mail: v.a.florenes@labmed.uio.no

    2005-04-01

    The phorbol ester, phorbol-12-myristate-13-acetate (PMA), an activator of PKCs, is known to stimulate the in vitro growth of monolayer cultures of normal human melanocytes whereas it inhibits the growth of most malignant melanoma cell lines. We examined the effect of PMA on proliferation and survival of melanoma cells grown as multicellular aggregates in suspension (spheroids), and aimed to elucidate downstream targets of PKC signaling. In contrast to monolayer cultures, PMA increased cell proliferation as well as protected melanoma cells from suspension-mediated apoptosis (anoikis). Supporting the importance of PKC in anchorage-independent growth, treatment of anoikis-resistant melanoma cell lines with antisense oligonucleotides against PKC-{alpha}, or the PKC inhibitor Goe6976, strongly induced anoikis. PMA induced activation of ERK1/2, but this effect was not prevented by the MEK inhibitors PD98059 or by U0126. Whereas PD98059 treatment alone led to marked activation of the pro-apoptotic Bim and Bad proteins and significantly increased anoikis, these effects were clearly reversed by PMA. In conclusion, our results indicate that the protective effect of PMA on anchorage-independent survival of melanoma cells at least partly is mediated by MEK-independent activation of ERK1/2 and inactivation of downstream pro-apoptotic effector proteins.

  20. Curcumin Represses NLRP3 Inflammasome Activation via TLR4/MyD88/NF-κB and P2X7R Signaling in PMA-Induced Macrophages

    PubMed Central

    Kong, Fanqi; Ye, Bozhi; Cao, Jiatian; Cai, Xueli; Lin, Lu; Huang, Shanjun; Huang, Weijian; Huang, Zhouqing

    2016-01-01

    Aims: In the NOD-like receptor (NLR) family, the pyrin domain containing 3 (NLRP3) inflammasome is closely related to the progression of atherosclerosis. This study aimed to assess the effects of curcumin on NLRP3 inflammasome in phorbol 12-myristate 13-acetate (PMA)-induced macrophages and explore its underlying mechanism. Methods: Human monocytic THP-1 cells were pretreated with curcumin for 1 h and subsequently induced with PMA for 48 h. Total protein was collected for Western blot analysis. Cytokine interleukin (IL)-1β release and nuclear factor kappa B (NF-κB) p65 translocation were detected by ELISA assay and cellular NF-κB translocation kit, respectively. Results: Curcumin significantly reduced the expression of NLRP3 and cleavage of caspase-1 and IL-1β secretion in PMA-induced macrophages. Moreover, Bay (a NF-κB inhibitor) treatment considerably suppressed the expression of NLRP3 inflammasome in PMA-induced THP-1 cells. Curcumin also markedly inhibited the upregulation of toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), phosphorylation level of IκB-α, and activation of NF-κB in PMA-induced macrophages. In addition, purinergic 2X7 receptor (P2X7R) siRNA was administered, and it significantly decreased NLRP3 inflammasome expression in PMA-induced macrophages. Furthermore, curcumin reversed PMA-stimulated P2X7R activation, which further reduced the expression of NLRP3 and cleavage of caspase-1 and IL-1β secretion. Silencing of P2X7R using siRNA also suppressed the activation of NF-κB pathway in PMA-induced macrophages, but P2X7R-silenced cells did not significantly decrease the expression of TLR4 and MyD88. Conclusion: Curcumin inhibited NLRP3 inflammasome through suppressing TLR4/MyD88/NF-κB and P2X7R pathways in PMA-induced macrophages. PMID:27777559

  1. High-density PhyloChip profiling of stimulated aquifer microbial communities reveals a complex response to acetate amendment

    SciTech Connect

    Handley, Kim M.; Wrighton, Kelly E.; Piceno, Y. M.; Anderson, Gary L.; DeSantis, Todd; Williams, Kenneth H.; Wilkins, Michael J.; N'Guessan, A. L.; Peacock, Aaron; Bargar, John R.; Long, Philip E.; Banfield, Jillian F.

    2012-06-13

    There is increasing interest in harnessing the functional diversity of indigenous microbial communities to transform and remediate a wide range of environmental contaminants. Understanding the response of communities to stimulation, including flanking taxa, presents important opportunities for optimizing remediation approaches. We used high-density PhyloChip microarray analysis to comprehensively determine community membership and abundance patterns amongst a suite of samples from U(VI) bioremediation experiments. Samples were unstimulated or collected during Fe(III) and sulfate reduction from an acetate-augmented aquifer in Rifle, Colorado, and from laboratory experiments using field-collected materials. Results showed the greatest diversity in abundant SRB lineages was present in naturally-reduced sediment. Desulfuromonadales and Desulfobacterales were consistently identified as the dominant Fe(III)- and sulfate-reducing bacteria (IRB and SRB) throughout acetate amendment experiments. Stimulated communities also exhibited a high degree of functional redundancy amongst enriched flanking members. Not surprisingly, competition for both sulfate and iron was evident amongst abundant taxa, but the distribution and abundance of these ancillary SRB (Peptococcaceae, Desulfovibrionales and Syntrophobacterales), and lineages containing IRB (excluding Desulfobacteraceae) was heterogeneous amongst sample types. Interesting, amongst the most abundant taxa, particularly during sulfate reduction, were Epsilonproteobacteria that perform microaerobic or nitrate-dependant sulfur oxidation, and a number of bacteria other than Geobacteraceae that may enzymatically reduce U(VI). Finally, in depth community probing with PhyloChip determined the efficacy of experimental approaches, notably revealing striking similarity amongst stimulated sediment (from drill cores and in-situ columns) and groundwater communities, and demonstrating that sediment-packed in-situ (down-well) columns served

  2. Effects of medroxyprogesterone acetate on subjective arousal, arousal to erotic stimulation, and nocturnal penile tumescence in male sex offenders.

    PubMed

    Wincze, J P; Bansal, S; Malamud, M

    1986-08-01

    Three chronic pedophiliac sex offenders were treated individually with medroxyprogesterone acetate (MPA) over a minimum of 3 months. Genital and subjective response to erotic stimulation, nocturnal penile tumescence, self-reporting of sexual urges, and testosterone levels were recorded repeatedly throughout the study. A single-subject reversal design was used and medication was administered through a double-blind procedure. The results showed that self-report of arousal outside of a laboratory setting was unreliable as a measure of the drug effect. In a laboratory setting, however, there appeared to be a significant reduction in the report of arousal to erotic stimuli while genital arousal decreased only slightly. Reversal of these responses occurred in only one subject during a final placebo phase. Nocturnal penile tumescence was significantly decreased during MPA administration and appeared to be related to decreases in total testosterone.

  3. Interferon-γ enhances phorbol myristate acetate-induced cell attachment and tumor necrosis factor production via the NF-κB pathway in THP-1 human monocytic cells.

    PubMed

    Kurihara, Yuichi; Furue, Masutaka

    2013-06-01

    During inflammation, activated macrophages express adhesion molecules and produce cytokines that interact with other hematopoietic and stromal cells. THP-1 non-adherent human monocytic cells differentiate into plastic-adherent macrophages via αVβ3 integrin, by ERK activation in the presence of phorbol myristate acetate (PMA). This has proven to be a valuable model for investigating functional monocyte/macrophage diversity. Interferon-γ (IFN-γ) is a Th1-cytokine that is crucial in macrophage activation. In this study, we investigated the effects of IFN-γ on adhesion and the secretion of tumor necrosis factor (TNF) by PMA-stimulated THP-1 cells. IFN-γ is incapable of inducing cell attachment and TNF production; however, it cumulatively upregulated PMA-induced basal adhesion and TNF production. IFN-γ increased αV integrin, ICAM-1 and VCAM-1 expression and among these PMA-induced cell surface adhesion molecules, the blocking antibody for αV integrin suppressed adhesion and TNF production. Furthermore, IFN-γ enhanced PMA-induced NF-κB phosphorylation and not ERK phosphorylation. Accordingly, the NF-κB pathway inhibitor (BAY 11-7082) inhibited the enhancing effect of IFN-γ on adhesion and TNF production. By contrast, the MEK inhibitor (U0126) almost completely eliminated PMA-induced basal adhesion and TNF production. In conclusion, IFN-γ regulates macrophage activation by mediating the NF-κB signaling pathway. PMID:23589028

  4. Interferon-γ enhances phorbol myristate acetate-induced cell attachment and tumor necrosis factor production via the NF-κB pathway in THP-1 human monocytic cells.

    PubMed

    Kurihara, Yuichi; Furue, Masutaka

    2013-06-01

    During inflammation, activated macrophages express adhesion molecules and produce cytokines that interact with other hematopoietic and stromal cells. THP-1 non-adherent human monocytic cells differentiate into plastic-adherent macrophages via αVβ3 integrin, by ERK activation in the presence of phorbol myristate acetate (PMA). This has proven to be a valuable model for investigating functional monocyte/macrophage diversity. Interferon-γ (IFN-γ) is a Th1-cytokine that is crucial in macrophage activation. In this study, we investigated the effects of IFN-γ on adhesion and the secretion of tumor necrosis factor (TNF) by PMA-stimulated THP-1 cells. IFN-γ is incapable of inducing cell attachment and TNF production; however, it cumulatively upregulated PMA-induced basal adhesion and TNF production. IFN-γ increased αV integrin, ICAM-1 and VCAM-1 expression and among these PMA-induced cell surface adhesion molecules, the blocking antibody for αV integrin suppressed adhesion and TNF production. Furthermore, IFN-γ enhanced PMA-induced NF-κB phosphorylation and not ERK phosphorylation. Accordingly, the NF-κB pathway inhibitor (BAY 11-7082) inhibited the enhancing effect of IFN-γ on adhesion and TNF production. By contrast, the MEK inhibitor (U0126) almost completely eliminated PMA-induced basal adhesion and TNF production. In conclusion, IFN-γ regulates macrophage activation by mediating the NF-κB signaling pathway.

  5. Contact sensitizers modulate the arachidonic acid metabolism of PMA-differentiated U-937 monocytic cells activated by LPS

    SciTech Connect

    Del Bufalo, Aurelia; Bernad, Jose; Dardenne, Christophe; Verda, Denis; Meunier, Jean Roch; Rousset, Francoise; Martinozzi-Teissier, Silvia; Pipy, Bernard

    2011-10-01

    For the effective induction of a hapten-specific T cell immune response toward contact sensitizers, in addition to covalent-modification of skin proteins, the redox and inflammatory statuses of activated dendritic cells are crucial. The aim of this study was to better understand how sensitizers modulate an inflammatory response through cytokines production and COX metabolism cascade. To address this purpose, we used the human monocytic-like U-937 cell line differentiated by phorbol myristate acetate (PMA) and investigated the effect of 6 contact sensitizers (DNCB, PPD, hydroquinone, propyl gallate, cinnamaldehyde and eugenol) and 3 non sensitizers (lactic acid, glycerol and tween 20) on the production of pro-inflammatory cytokines (IL-1{beta} and TNF-{alpha}) and on the arachidonic acid metabolic profile after bacterial lipopolysaccharide (LPS) stimulation. Our results showed that among the tested molecules, all sensitizers specifically prevent the production of PMA/LPS-induced COX-2 metabolites (PGE{sub 2,} TxB{sub 2} and PGD{sub 2}), eugenol and cinnamaldehyde inhibiting also the production of IL-1{beta} and TNF-{alpha}. We further demonstrated that there is no unique PGE{sub 2} inhibition mechanism: while the release of arachidonic acid (AA) from membrane phospholipids does not appear do be a target of modulation, COX-2 expression and/or COX-2 enzymatic activity are the major steps of prostaglandin synthesis that are inhibited by sensitizers. Altogether these results add a new insight into the multiple biochemical effects described for sensitizers. - Highlights: > We investigated how contact sensitizers modulate an inflammatory response. > We used macrophage-differentiated cell line, U-937 treated with PMA/LPS. > Sensitizers specifically inhibit the production of COX metabolites (PGE2, TxB2). > Several mechanisms of inhibition: COX-2 expression/enzymatic activity, isomerases. > New insight in the biochemical properties of sensitizers.

  6. Controlled Ovarian Stimulation Using Medroxyprogesterone Acetate and hMG in Patients With Polycystic Ovary Syndrome Treated for IVF

    PubMed Central

    Wang, Yun; Chen, Qiuju; Wang, NingLing; Chen, Hong; Lyu, Qifeng; Kuang, Yanping

    2016-01-01

    Abstract Ovarian hyperstimulation syndrome (OHSS) during ovarian stimulation is a current challenge for patients with polycystic ovarian syndrome (PCOS). Our previous studies indicated that progestin can prevent premature luteinizing hormone (LH) surge or moderate/severe OHSS in the general subfertile population, both in the follicular-phase and luteal-phase ovarian stimulation but it is unclear if this is true for patients with PCOS. The aim of the article was to analyze cycle characteristics and endocrinological profiles using human menopausal gonadotropin (hMG) in combination with medroxyprogesterone acetate (MPA) for PCOS patients who are undergoing IVF/intracytoplasmic sperm injection (ICSI) treatments and investigate the subsequently pregnancy outcomes of frozen embryo transfer (FET). In the randomized prospective controlled study, 120 PCOS patients undergoing IVF/ICSI were recruited and randomly classified into 2 groups according to the ovarian stimulation protocols: hMG and MPA (group A, n = 60) or short protocol (group B, n = 60). In the study group, hMG (150–225IU) and MPA (10 mg/d) were administered simultaneously beginning on cycle day 3. Ovulation was cotriggered by a gonadotropinreleasing hormone (GnRH) agonist (0.1 mg) and hCG (1000IU) when dominant follicles matured. A short protocol was used as a control. The primary end-point was the ongoing pregnancy rate per transfer and incidence of OHSS. Doses of hMG administrated in group A are significantly higher than those in the controls. LH suppression persisted during ovarian stimulation and no incidence of premature LH surge was seen in both groups. The fertilization rate and the ongoing pregnant rate in the study group were higher than that in the control. The number of oocytes retrieved, mature oocytes, clinical pregnancy rates per transfer, implantation rates, and cumulative pregnancy rates per patient were comparable between the 2 groups. The incidence of OHSS was low between the 2

  7. Phorbol ester stimulates calcium sequestration in saponized human platelets

    SciTech Connect

    Yoshida, K.; Nachmias, V.T.

    1987-11-25

    When platelets are activated by agonists, calcium (Ca2+) is released from an intracellular storage site. Recent studies using fura-2 show that, after thrombin stimulation, the rise in free calcium is transient and returns to base-line levels in 2-3 min, while the transient following ADP stimulation lasts only 15-20 s. We reported previously that the phorbol ester 12,13-phorbol myristate acetate (PMA), added at nanomolar levels after thrombin, immediately accelerated the rate of return of calcium to the base line severalfold. In the present study, we used both intact and saponized platelets to determine whether this is due to stimulation of calcium sequestration. Using fura-2 and intact platelets, we found 1) that PMA stimulated the restoration of free Ca2+ levels after ADP as well as after thrombin, and 2) that H-7, an inhibitor of protein kinase C (Ca2+/phospholipid-dependent enzyme), slowed the return of Ca2+ to baseline levels. Using saponized platelets, we also found 3) that pretreatment of platelets with PMA before saponin treatment increased the ATP-dependent /sup 45/Ca2+ uptake 2-fold, with a half-maximal effect at 5 nm; 4) that most of the Ca2+ released by ionomycin or by myoinositol 1,4,5-trisphosphate; and 5) that a GTP-binding protein inhibitor, guanosine 5'-O-(2-thiodiphosphate), decreased basal or PMA-stimulated /sup 45/Ca2+ uptake in saponin-treated platelets. Our data suggest that activation of protein kinase C stimulates the sequestration of Ca2+ independently of cAMP or myoinositol 1,4,5-trisphosphate.

  8. Ent-2'-epi-Orobanchol and its acetate, as germination stimulants for Striga gesnerioides seeds isolated from cowpea and red clover.

    PubMed

    Ueno, Kotomi; Nomura, Saki; Muranaka, Satoru; Mizutani, Masaharu; Takikawa, Hirosato; Sugimoto, Yukihiro

    2011-10-12

    Striga gesnerioides is a root parasitic weed of economic significance to cowpea (Vigna unguiculata) crops in Western Africa. Seeds of the parasite germinate in response to cowpea root exudates. Germination stimulants for the seeds were isolated from the hydroponic culture filtrate of cowpea, and their structures were unambiguously determined as (-)-(3aR,4R,8bR,2'R)-ent-2'-epi-orobanchol and (+)-(3aR,4R,8bR,2'R)-ent-2'-epi-orobanchyl acetate, on the basis of mass, CD, and (1)H NMR spectra; optical rotatory power; and chromatographic behavior on HPLC. The alcohol was first isolated and identified from the cowpea root exudates, and the acetate may be the same compound that had been previously isolated from the exudates and designated as alectrol. Identity of the stimulants produced by cowpea to those produced by red clover (Trifolium pratense) was confirmed.

  9. Involvement of PKC{alpha} in PMA-induced facilitation of exocytosis and vesicle fusion in PC12 cells

    SciTech Connect

    Xue Renhao; Zhao Yanying; Chen Peng

    2009-03-06

    Phorbol-12-myristate-13-acetate, a stable analog of the important signaling membrane lipid diacylglycerol (DAG), is known to potentiate exocytosis and modulate vesicle fusion kinetics in neurons and endocrine cells. The exact mechanisms underlying the actions of PMA, however, is often not clear, largely because of the diversity of the DAG/PMA receptors involved in the exocytotic process, which include, most notably, various isoforms of protein kinase C (PKC). In this study, the roles of PKC{alpha} in PMA-mediated regulation of exocytosis were investigated by over-expressing wild-type PKC{alpha} (wt-PKC{alpha}) or dominant negative PKC{alpha} (dn-PKC{alpha}). Amperometric measurements based on carbon fiber microelectrodes demonstrated that PKC{alpha} has a key role in the PMA-mediated facilitation of exocytosis and vesicle fusion in neuroendocrine PC12 cells.

  10. Modulation of the expression of chondroitin sulfate proteoglycan in stimulated human monocytes

    SciTech Connect

    Uhlin-Hansen, L.; Eskeland, T.; Kolset, S.O. )

    1989-09-05

    Proteoglycan biosynthesis was studied in human monocytes and monocyte-derived macrophages (MDM) after exposure to typical activators of the monocyte/macrophage system: interferon-gamma (IFN-gamma), lipopolysaccharide (LPS), and phorbol 12-myristate 13-acetate (PMA). By morphological examination, both monocytes and MDM were stimulated by these activators. Treatment with IFN-gamma resulted in a slight decrease in the expression of (35S)chondroitin sulfate proteoglycan (CSPG) in both monocytes and MDM, whereas LPS treatment increased the (35S)CSPG expression 1.8 and 2.2 times, respectively. PMA, in contrast, decreased the CSPG expression 0.4 times in monocytes, whereas MDM were stimulated to increase the biosynthesis 1.9 times. An increase in the sulfate density of the chondroitin sulfate chains was evident following differentiation of monocytes into MDM due to the expression of disulfated disaccharide units of the chondroitin sulfate E type (CS-E). However, monocytes exposed to PMA did also express disaccharides of the chondroitin sulfate E type. Furthermore, the expression of CS-E in MDM was increased 2 times following PMA treatment. An inactive phorbol ester, phorbol 12,13-diacetate, did not affect the expression of CS-E in either monocytes or MDM when compared with control cultures, suggesting that protein kinase C-dependent signal pathways may be involved in the regulation of sulfation of CSPG. Exposure to LPS or IFN-gamma did not lead to any changes in the sulfation of the chondroitin sulfate chains.

  11. Short-Chain Fatty Acid Acetate Stimulates Adipogenesis and Mitochondrial Biogenesis via GPR43 in Brown Adipocytes.

    PubMed

    Hu, Jiamiao; Kyrou, Ioannis; Tan, Bee K; Dimitriadis, Georgios K; Ramanjaneya, Manjunath; Tripathi, Gyanendra; Patel, Vanlata; James, Sean; Kawan, Mohamed; Chen, Jing; Randeva, Harpal S

    2016-05-01

    Short-chain fatty acids play crucial roles in a range of physiological functions. However, the effects of short-chain fatty acids on brown adipose tissue have not been fully investigated. We examined the role of acetate, a short-chain fatty acid formed by fermentation in the gut, in the regulation of brown adipocyte metabolism. Our results show that acetate up-regulates adipocyte protein 2, peroxisomal proliferator-activated receptor-γ coactivator-1α, and uncoupling protein-1 expression and affects the morphological changes of brown adipocytes during adipogenesis. Moreover, an increase in mitochondrial biogenesis was observed after acetate treatment. Acetate also elicited the activation of ERK and cAMP response element-binding protein, and these responses were sensitive to G(i/o)-type G protein inactivator, Gβγ-subunit inhibitor, phospholipase C inhibitor, and MAPK kinase inhibitor, indicating a role for the G(i/o)βγ/phospholipase C/protein kinase C/MAPK kinase signaling pathway in these responses. These effects of acetate were mimicked by treatment with 4-chloro-α-(1-methylethyl)-N-2-thiazolylbenzeneacetamide, a synthetic G protein-coupled receptor 43 (GPR43) agonist and were impaired in GPR43 knockdown cells. Taken together, our results indicate that acetate may have important physiological roles in brown adipocytes through the activation of GPR43. PMID:26990063

  12. beta. -Endorphin and related peptides suppress phorbol myristate acetate-induced respiratory burst in human polymorphonuclear leukocytes

    SciTech Connect

    Diamant, M.; Henricks, P.A.J.; Nijkamp, F.P.; de Wied, D. )

    1989-01-01

    In the present study, the immunomodulatory effect of {beta}-endorphin ({beta}-E) and shorter pro-opiomelancortin (POMC) fragments was evaluated by assessing their influence on respiratory burst in human polymorphonuclear leukocytes (PMN). The effect of the peptides on phorbol myristate acetate (PMA)-stimulated production of reactive oxygen metabolites was measured in a lucigenin-enhanced chemiluminescence (CL) assay. Both POMC peptides with opiate-like activity and their non-opioid derivatives were tested. With the exception of {alpha}-E, PMA-stimulated respiratory burst was suppressed by all POMC fragments tested. A U-shaped dose-response relation was observed. Doses lower than 10{sup {minus}17}M and higher than 10{sup {minus}8}M were without effect. {beta}-E and dT{beta}E both suppressed PMA-induced oxidative burst in human PMN at physiological concentrations. {gamma}-E and dT{gamma}E proved to be less potent inhibitors, reaching maximal effect at higher concentrations. DE{gamma}E exerted an even less pronounced but still significant suppressive effect at the concentration of 10{sup {minus}10}M. None of the endorphins tested was shown to affect resting oxidative metabolism in the PMN. The modulatory effects of the opioid peptides could not be blocked by the opioid antagonist naloxone.

  13. New and emerging treatments for epilepsy: review of clinical studies of lacosamide, eslicarbazepine acetate, ezogabine, rufinamide, perampanel, and electrical stimulation therapy.

    PubMed

    Chung, Steve S; Kelly, Kristen; Schusse, Courtney

    2011-12-01

    Although many different medical and surgical treatment options for epilepsy exist, approximately 30% of epilepsy patients remain poorly controlled. For those patients who are refractory to medical treatment, epilepsy surgery often provides meaningful improvement. However, when surgical resection of epileptic foci cannot be offered or failed, combined administration of AEDs or the application of novel AEDs is the most appropriate therapeutic options. The most recent AEDs tend to offer new mechanisms of action and more favorable safety profiles than the first generation of AEDs. More recently, alternative options of thalamic or cortical stimulation emerged as potentiall effective treatment for epilepsy. The purpose of this article is to compare and review clinical information for the new and emerging medications such as lacosamide, eslicarbazepine acetate, ezogabine (retigabine), rufinamide, perampanel, as well as deep brain stimulation and responsive neurostimulation devices. PMID:24649444

  14. Pharmacodynamics of aqueous leuprolide acetate stimulation testing in girls: correlation between clinical diagnosis and time of peak luteinizing hormone level.

    PubMed

    Chi, Carolyn H; Durham, Eileen; Neely, E Kirk

    2012-10-01

    We assessed the pharmacodynamics of a 3-hour leuprolide stimulation test in 11 girls with precocious puberty to determine an optimal single sampling time. Luteinizing hormone level following leuprolide stimulation was near maximum by 30 minutes in girls with central precocious puberty, whereas it continued to rise slowly in girls with nonprogressive puberty.

  15. Medicolegal aspects of PMA-related deaths.

    PubMed

    Rojek, Sebastian; Bolechała, Filip; Kula, Karol; Maciów-Głąb, Martyna; Kłys, Małgorzata

    2016-07-01

    Unlike amphetamine, amphetamine-like substances accessible on the drug market are less expensive and more easily available; they also produce hallucinogenic effects expected by the users. Such properties render them more attractive as compared to amphetamine. On the other hand, the knowledge of the toxicity of these compounds is very limited, what in consequence generates problems that create ever-expanding research areas, including analytical, clinical and medicolegal issues, thus leading to development of systemic databases. An example here is paramethoxyamphetamine (PMA), which appeared on the drug market in recent years as a result of creative inventiveness of producers of psychoactive substances, who aimed at PMA replacing the popular ecstasy (MDMA) as a less expensive and more available product. It is more potent than MDMA, but has a slower onset of action, which encourages users to take more. The problem is illustrated in the present paper by three fatal cases involving PMA, which were comprehensively investigated taking into consideration case histories, pathological and toxicological findings obtained with the use of LC-MS-MS method. In blood samples taken from all the three victims, very high concentrations of PMA were found (in the range of 10-27mg/L) and thus the cause of deaths was determined as overdoses of PMA with the underlying mechanism of acute cardiorespiratory failure. PMID:27497336

  16. Stimulants

    MedlinePlus

    Stimulants are drugs that increase your heart rate, breathing rate, and brain function. Some stimulants affect only a specific organ, such as the heart, lungs, brain, or nervous system. Epinephrine is a stimulant. It ...

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

    SciTech Connect

    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.

  18. Thyrotropin inhibits while insulin, epidermal growth factor and tetradecanoyl phorbol acetate stimulate insulin-like growth factor binding protein secretion from sheep thyroid cells.

    PubMed

    Eggo, M C; Bachrach, L K; Brown, A L; Burrow, G N

    1991-01-01

    Six insulin-like growth factor binding proteins (IGFBP) have been identified in the conditioned medium from sheep thyroid cells cultured under serum-free conditions. IGFBPs of 32, 28, 23 and 19 kDa were secreted by cells cultured for 14 days in serum-free and hormone-free medium. The constitutive secretion of IGFBP was inhibited by thyrotropin (TSH, 0.3 mU per mL). The effect was most marked on the secretion of the 28 kDa BP. High insulin concentrations stimulated the secretion of this IGFBP. The stimulatory effects of insulin were inhibited by TSH. Growth hormone treatment decreased the secretion of the 28 kDa protein. Tetradecanoylphorbol-13 acetate (TPA) and epidermal growth factor (EGF) both of which stimulate thyroid cell growth but inhibit differentiated function, markedly stimulated IGFBP secretion and induced the appearance of a 46 and a 150 kDa IGFBP. The effects of EGF and TPA were not identical. A rat IGFBP-2 cDNA reacted with sheep thyroid RNA of approximate size 1.6 kb. TPA treatment increased IGFBP-2 mRNA. Other hormones used to enhance differentiation and growth in thyroid cells in culture i.e. transferrin, somatostatin, cortisol and glycyl-histidyl-lysine acetate had no marked effects on IGFBP secretion nor on TSH-dependent, insulin-mediated iodide uptake and organification and cell growth. We show a correlation between secretion of high molecular weight IGFBP with enhanced growth but decreased function. Conversely, we find a correlation between decreased secretion of the 28 kDa BP and increased growth and function. PMID:1722684

  19. 21 CFR 814.42 - Filing a PMA.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Filing a PMA. 814.42 Section 814.42 Food and Drugs... PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.42 Filing a PMA. (a) The filing of an... permit a substantive review. Within 45 days after a PMA is received by FDA, the agency will notify...

  20. 21 CFR 814.42 - Filing a PMA.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Filing a PMA. 814.42 Section 814.42 Food and Drugs... PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.42 Filing a PMA. (a) The filing of an... permit a substantive review. Within 45 days after a PMA is received by FDA, the agency will notify...

  1. 21 CFR 814.39 - PMA supplements.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false PMA supplements. 814.39 Section 814.39 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES... of the expiration date of the device based on data obtained under a new or revised stability...

  2. 21 CFR 814.39 - PMA supplements.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false PMA supplements. 814.39 Section 814.39 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES... based on data obtained under a new or revised stability or sterility testing protocol that has not...

  3. 21 CFR 814.39 - PMA supplements.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false PMA supplements. 814.39 Section 814.39 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES..., modifications to manufacturing procedures or methods of manufacture that affect the safety and effectiveness...

  4. Reduced PMA enhances the responsiveness of transfected THP-1 macrophages to polarizing stimuli.

    PubMed

    Maeß, Marten B; Wittig, Berith; Cignarella, Andrea; Lorkowski, Stefan

    2014-01-15

    Macrophages are versatile cells of the immune system which react to various external stimuli through different polarization patterns which adjust the cells to the required function whether it is removal of pathogens or necrotic cells, tissue repair or propagation of inflammation. As much of macrophage behavior is determined by their polarization, appropriate models to study macrophage polarization are required. Previously we have published a protocol for transfection of THP-1 macrophages, which in brief pre-differentiates THP-1 monocytes for 48h using 100ng/ml PMA, followed by detachment of the cells and eletroporation using Lonza nucleofector technology and finally includes further 48h of differentiation with 100ng/ml PMA. When we applied this protocol to study interleukin (IL) 10 dependent polarization, the cells were inert to the IL10 stimulus, as indicated by a failure to induce IL10 target genes such as SOCS3. Further investigation revealed that the cells were classically activated by the differentiation agent phorbol 12-myristate 13-acetate (PMA) as shown by induction of chemokine receptor CCR7. Subsequent reduction of PMA concentration during THP-1 macrophage differentiation significantly improved their response to IL10 as SOCS3 increased more than 40-fold. This increased responsiveness of the THP-1 macrophages was also confirmed for polarization with LPS and IFNγ. Up-regulation of classical activation markers CCL3, CCR7 and TNFα was enhanced from 18-, 21- and 70-fold, respectively, to 48-, 222- and 951-fold, respectively. Reduction of PMA concentration did not negatively affect macrophage differentiation or transfection efficiency. Expression of macrophage differentiation markers CD11b and CD68 as well as cell morphology remained unchanged. In addition transfection efficiency and rates of apoptosis and necrosis remained unaffected. Thus our revised protocol combines high transfection efficiency and cell vitality with a strong response to polarizing

  5. Actin induction during PMA and cAMP-dependent signal pathway activation in Entamoeba histolytica trophozoites.

    PubMed

    Ortiz, D; del Carmen Dominguez-Robles, M; Villegas-Sepúlveda, N; Meza, I

    2000-10-01

    Activation of PKC or cAMP-dependent signalling pathways in Entamoeba histolytica triggers the phosphorylation of proteins involved in actin rearrangements necessary for adhesion and locomotion. Analogous motifs to SRE and CRE sequences--known to respond to PMA and cAMP--were identified within the 5' regulatory region (5'RR) of one of the parasite actin genes. These sequences could be involved in the actin transcriptional upregulation reported during signalling. To test this hypothesis, a plasmid containing the 5'RR of the actin gene fused to the bacterial neomycin gene (neo) was used for stable transfection. Expression of neo and endogenous actin was measured after stimulation of transfected amoebae by PMA and dcAMP. It was found that both compounds induced neo and actin expression and showed a co-operative effect in the induction of neo. Induction by PMA or dcAMP failed if the directing amoebic 5'RR lacked SRE and CRE motifs. Transfection of amoebae with plasmid constructs, containing either progressive deletions of the actin 5'RR or site-directed mutations of the SRE and CRE-like motifs, corroborated that these sequences and a co-ordinated participation of PKC- and PKA-activated transcription factors are responsible for the increments in neo and actin mRNAs. In vivo, these PMA and cAMP-response elements could play an important role in regulating actin expression and organization in signalling processes activated during tissue invasion.

  6. Structural correlates of cytoplasmic and chloroplast lipid body synthesis in Chlamydomonas reinhardtii and stimulation of lipid body production with acetate boost.

    PubMed

    Goodson, Carrie; Roth, Robyn; Wang, Zi Teng; Goodenough, Ursula

    2011-12-01

    Light microscopy and deep-etch electron microscopy were used to visualize triacylglyceride (TAG)-filled lipid bodies (LBs) of the green eukaryotic soil alga Chlamydomonas reinhardtii, a model organism for biodiesel production. Cells growing in nitrogen-replete media contain small cytoplasmic lipid bodies (α-cyto-LBs) and small chloroplast plastoglobules. When starved for N, β-cyto-LB formation is massively stimulated. β-Cyto-LBs are intimately associated with both the endoplasmic reticulum membrane and the outer membrane of the chloroplast envelope, suggesting a model for the active participation of both organelles in β-cyto-LB biosynthesis and packaging. When sta6 mutant cells, blocked in starch biosynthesis, are N starved, they produce β-cyto-LBs and also chloroplast LBs (cpst-LBs) that are at least 10 times larger than plastoglobules and eventually engorge the chloroplast stroma. Production of β-cyto-LBs and cpst-LBs under the conditions we used is dependent on exogenous 20 mM acetate. We propose that the greater TAG yields reported for N-starved sta6 cells can be attributed to the strain's ability to produce cpst-LBs, a capacity that is lost when the mutant is complemented by a STA6 transgene. Provision of a 20 mM acetate "boost" during N starvation generates sta6 cells that become so engorged with LBs-at the expense of cytoplasm and most organelles-that they float on water even when centrifuged. This property could be a desirable feature for algal harvesting during biodiesel production.

  7. Structural correlates of cytoplasmic and chloroplast lipid body synthesis in Chlamydomonas reinhardtii and stimulation of lipid body production with acetate boost.

    PubMed

    Goodson, Carrie; Roth, Robyn; Wang, Zi Teng; Goodenough, Ursula

    2011-12-01

    Light microscopy and deep-etch electron microscopy were used to visualize triacylglyceride (TAG)-filled lipid bodies (LBs) of the green eukaryotic soil alga Chlamydomonas reinhardtii, a model organism for biodiesel production. Cells growing in nitrogen-replete media contain small cytoplasmic lipid bodies (α-cyto-LBs) and small chloroplast plastoglobules. When starved for N, β-cyto-LB formation is massively stimulated. β-Cyto-LBs are intimately associated with both the endoplasmic reticulum membrane and the outer membrane of the chloroplast envelope, suggesting a model for the active participation of both organelles in β-cyto-LB biosynthesis and packaging. When sta6 mutant cells, blocked in starch biosynthesis, are N starved, they produce β-cyto-LBs and also chloroplast LBs (cpst-LBs) that are at least 10 times larger than plastoglobules and eventually engorge the chloroplast stroma. Production of β-cyto-LBs and cpst-LBs under the conditions we used is dependent on exogenous 20 mM acetate. We propose that the greater TAG yields reported for N-starved sta6 cells can be attributed to the strain's ability to produce cpst-LBs, a capacity that is lost when the mutant is complemented by a STA6 transgene. Provision of a 20 mM acetate "boost" during N starvation generates sta6 cells that become so engorged with LBs-at the expense of cytoplasm and most organelles-that they float on water even when centrifuged. This property could be a desirable feature for algal harvesting during biodiesel production. PMID:22037181

  8. Controlled Ovarian Stimulation Using Medroxyprogesterone Acetate and hMG in Patients With Polycystic Ovary Syndrome Treated for IVF: A Double-Blind Randomized Crossover Clinical Trial.

    PubMed

    Wang, Yun; Chen, Qiuju; Wang, NingLing; Chen, Hong; Lyu, Qifeng; Kuang, Yanping

    2016-03-01

    Ovarian hyperstimulation syndrome (OHSS) during ovarian stimulation is a current challenge for patients with polycystic ovarian syndrome (PCOS). Our previous studies indicated that progestin can prevent premature luteinizing hormone (LH) surge or moderate/severe OHSS in the general subfertile population, both in the follicular-phase and luteal-phase ovarian stimulation but it is unclear if this is true for patients with PCOS. The aim of the article was to analyze cycle characteristics and endocrinological profiles using human menopausal gonadotropin (hMG) in combination with medroxyprogesterone acetate (MPA) for PCOS patients who are undergoing IVF/intracytoplasmic sperm injection (ICSI) treatments and investigate the subsequently pregnancy outcomes of frozen embryo transfer (FET). In the randomized prospective controlled study, 120 PCOS patients undergoing IVF/ICSI were recruited and randomly classified into 2 groups according to the ovarian stimulation protocols: hMG and MPA (group A, n = 60) or short protocol (group B, n = 60). In the study group, hMG (150-225IU) and MPA (10 mg/d) were administered simultaneously beginning on cycle day 3. Ovulation was cotriggered by a gonadotropinreleasing hormone (GnRH) agonist (0.1 mg) and hCG (1000IU) when dominant follicles matured. A short protocol was used as a control. The primary end-point was the ongoing pregnancy rate per transfer and incidence of OHSS. Doses of hMG administrated in group A are significantly higher than those in the controls. LH suppression persisted during ovarian stimulation and no incidence of premature LH surge was seen in both groups. The fertilization rate and the ongoing pregnant rate in the study group were higher than that in the control. The number of oocytes retrieved, mature oocytes, clinical pregnancy rates per transfer, implantation rates, and cumulative pregnancy rates per patient were comparable between the 2 groups. The incidence of OHSS was low between the 2 groups, with

  9. Controlled Ovarian Stimulation Using Medroxyprogesterone Acetate and hMG in Patients With Polycystic Ovary Syndrome Treated for IVF: A Double-Blind Randomized Crossover Clinical Trial.

    PubMed

    Wang, Yun; Chen, Qiuju; Wang, NingLing; Chen, Hong; Lyu, Qifeng; Kuang, Yanping

    2016-03-01

    Ovarian hyperstimulation syndrome (OHSS) during ovarian stimulation is a current challenge for patients with polycystic ovarian syndrome (PCOS). Our previous studies indicated that progestin can prevent premature luteinizing hormone (LH) surge or moderate/severe OHSS in the general subfertile population, both in the follicular-phase and luteal-phase ovarian stimulation but it is unclear if this is true for patients with PCOS. The aim of the article was to analyze cycle characteristics and endocrinological profiles using human menopausal gonadotropin (hMG) in combination with medroxyprogesterone acetate (MPA) for PCOS patients who are undergoing IVF/intracytoplasmic sperm injection (ICSI) treatments and investigate the subsequently pregnancy outcomes of frozen embryo transfer (FET). In the randomized prospective controlled study, 120 PCOS patients undergoing IVF/ICSI were recruited and randomly classified into 2 groups according to the ovarian stimulation protocols: hMG and MPA (group A, n = 60) or short protocol (group B, n = 60). In the study group, hMG (150-225IU) and MPA (10 mg/d) were administered simultaneously beginning on cycle day 3. Ovulation was cotriggered by a gonadotropinreleasing hormone (GnRH) agonist (0.1 mg) and hCG (1000IU) when dominant follicles matured. A short protocol was used as a control. The primary end-point was the ongoing pregnancy rate per transfer and incidence of OHSS. Doses of hMG administrated in group A are significantly higher than those in the controls. LH suppression persisted during ovarian stimulation and no incidence of premature LH surge was seen in both groups. The fertilization rate and the ongoing pregnant rate in the study group were higher than that in the control. The number of oocytes retrieved, mature oocytes, clinical pregnancy rates per transfer, implantation rates, and cumulative pregnancy rates per patient were comparable between the 2 groups. The incidence of OHSS was low between the 2 groups, with

  10. 21 CFR 814.44 - Procedures for review of a PMA.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Procedures for review of a PMA. 814.44 Section 814...) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.44 Procedures for review of a PMA. (a) FDA will begin substantive review of a PMA after the PMA is accepted for filing...

  11. Protein Kinase Cα (PKCα) Is Resistant to Long Term Desensitization/Down-regulation by Prolonged Diacylglycerol Stimulation.

    PubMed

    Lum, Michelle A; Barger, Carter J; Hsu, Alice H; Leontieva, Olga V; Black, Adrian R; Black, Jennifer D

    2016-03-18

    Sustained activation of PKCα is required for long term physiological responses, such as growth arrest and differentiation. However, studies with pharmacological agonists (e.g. phorbol 12-myristate 13-acetate (PMA)) indicate that prolonged stimulation leads to PKCα desensitization via dephosphorylation and/or degradation. The current study analyzed effects of chronic stimulation with the physiological agonist diacylglycerol. Repeated addition of 1,2-dioctanoyl-sn-glycerol (DiC8) resulted in sustained plasma membrane association of PKCα in a pattern comparable with that induced by PMA. However, although PMA potently down-regulated PKCα, prolonged activation by DiC8 failed to engage known desensitization mechanisms, with the enzyme remaining membrane-associated and able to support sustained downstream signaling. DiC8-activated PKCα did not undergo dephosphorylation, ubiquitination, or internalization, early events in PKCα desensitization. Although DiC8 efficiently down-regulated novel PKCs PKCδ and PKCϵ, differences in Ca(2+) sensitivity and diacylglycerol affinity were excluded as mediators of the selective resistance of PKCα. Roles for Hsp/Hsc70 and Hsp90 were also excluded. PMA, but not DiC8, targeted PKCα to detergent-resistant membranes, and disruption of these domains with cholesterol-binding agents demonstrated a role for differential membrane compartmentalization in selective agonist-induced degradation. Chronic DiC8 treatment failed to desensitize PKCα in several cell types and did not affect PKCβI; thus, conventional PKCs appear generally insensitive to desensitization by sustained diacylglycerol stimulation. Consistent with this conclusion, prolonged (several-day) membrane association/activation of PKCα is seen in self-renewing epithelium of the intestine, cervix, and skin. PKCα deficiency affects gene expression, differentiation, and tumorigenesis in these tissues, highlighting the importance of mechanisms that protect PKCα from

  12. Induction of megakaryocytic colony-stimulating activity in mouse skin by inflammatory agents and tumor promoters

    SciTech Connect

    Clark, D.A.; Dessypris, E.N.; Koury, M.J.

    1987-03-01

    The production of megakaryocytic colony-stimulating activity (MEG-CSA) was assayed in acetic acid extracts of skin from mice topically treated with inflammatory and tumor-promoting agents. A rapid induction of MEG-CSA was found in skin treated both with phorbol 12-myristate 13-acetate (PMA), a strong tumor promoter, and with mezerein, a weak tumor promoter, but no induction was found in untreated skin. The time course of induction of MEG-CSA following treatment of skin with PMA or mezerein was very similar to that previously demonstrated for the induction of granulocyte-macrophage colony-stimulating activity in mouse skin by these agents. The induced MEG-CSA was found in both the epidermis and the dermis. Pretreatment of the skin with US -methasone abrogated the MEG-CSA induction. The cell number response curve suggests that the MEG-CSA acts directly on the progenitor cells of the megakaryocyte colonies. That topical administration of diterpene esters results in the rapid, local induction of MEG-CSA which can be blocked by US -methasone pretreatment suggests a mechanism for the thrombocytosis associated with some inflammatory states. The indirect action in which diterpene esters induce in certain cells the production or release of growth regulatory factors for other cell types may also aid in understanding their carcinogenic properties.

  13. Silver nanoparticles impede phorbol myristate acetate-induced monocyte-macrophage differentiation and autophagy

    NASA Astrophysics Data System (ADS)

    Xu, Yingying; Wang, Liming; Bai, Ru; Zhang, Tianlu; Chen, Chunying

    2015-09-01

    Monocytes/macrophages are important constituents of the innate immune system. Monocyte-macrophage differentiation is not only crucial for innate immune responses, but is also related to some cardiovascular diseases. Silver nanoparticles (AgNPs) are one of the most widely used nanomaterials because of their broad-spectrum antimicrobial properties. However, the effect of AgNPs on the functions of blood monocytes is scarcely reported. Here, we report the impedance effect of AgNPs on THP-1 monocyte differentiation, and that this effect was mediated by autophagy blockade and lysosomal impairment. Firstly, AgNPs inhibit phorbol 12-myristate 13-acetate (PMA)-induced monocyte differentiation by down-regulating both expression of surface marker CD11b and response to lipopolysaccharide (LPS) stimulation. Secondly, autophagy is activated during PMA-induced THP-1 monocyte differentiation, and the autophagy inhibitor chloroquine (CQ) can inhibit this process. Thirdly, AgNPs block the degradation of the autophagy substrate p62 and induce autophagosome accumulation, which demonstrates the blockade of autophagic flux. Fourthly, lysosomal impairments including alkalization and decrease of lysosomal membrane stability were observed in AgNP-treated THP-1 cells. In conclusion, we demonstrate that the impedance of monocyte-macrophage differentiation by AgNPs is mediated by autophagy blockade and lysosomal dysfunction. Our results suggest that crosstalk exists in different biological effects induced by AgNPs.

  14. Silver nanoparticles impede phorbol myristate acetate-induced monocyte-macrophage differentiation and autophagy.

    PubMed

    Xu, Yingying; Wang, Liming; Bai, Ru; Zhang, Tianlu; Chen, Chunying

    2015-10-14

    Monocytes/macrophages are important constituents of the innate immune system. Monocyte-macrophage differentiation is not only crucial for innate immune responses, but is also related to some cardiovascular diseases. Silver nanoparticles (AgNPs) are one of the most widely used nanomaterials because of their broad-spectrum antimicrobial properties. However, the effect of AgNPs on the functions of blood monocytes is scarcely reported. Here, we report the impedance effect of AgNPs on THP-1 monocyte differentiation, and that this effect was mediated by autophagy blockade and lysosomal impairment. Firstly, AgNPs inhibit phorbol 12-myristate 13-acetate (PMA)-induced monocyte differentiation by down-regulating both expression of surface marker CD11b and response to lipopolysaccharide (LPS) stimulation. Secondly, autophagy is activated during PMA-induced THP-1 monocyte differentiation, and the autophagy inhibitor chloroquine (CQ) can inhibit this process. Thirdly, AgNPs block the degradation of the autophagy substrate p62 and induce autophagosome accumulation, which demonstrates the blockade of autophagic flux. Fourthly, lysosomal impairments including alkalization and decrease of lysosomal membrane stability were observed in AgNP-treated THP-1 cells. In conclusion, we demonstrate that the impedance of monocyte-macrophage differentiation by AgNPs is mediated by autophagy blockade and lysosomal dysfunction. Our results suggest that crosstalk exists in different biological effects induced by AgNPs. PMID:26372376

  15. 21 CFR 814.42 - Filing a PMA.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.42 Filing a PMA. (a) The filing of an... conference with the Director of the Office of Device Evaluation to review FDA's decision not to file the...

  16. 21 CFR 814.42 - Filing a PMA.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.42 Filing a PMA. (a) The filing of an... conference with the Director of the Office of Device Evaluation to review FDA's decision not to file the...

  17. 21 CFR 814.42 - Filing a PMA.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.42 Filing a PMA. (a) The filing of an... conference with the Director of the Office of Device Evaluation to review FDA's decision not to file the...

  18. Glycoprotein isolated from Solanum nigrum L. modulates the apoptotic-related signals in 12-O-tetradecanoylphorbol 13-acetate-stimulated MCF-7 cells.

    PubMed

    Heo, Kyung-Sun; Lim, Kye-Taek

    2005-01-01

    Solanum nigrum L. (SNL) has been used in folk medicine for its anti-inflammatory activity. We isolated only the SNL glycoprotein from SNL and found that it was cytotoxic at low concentration. With respect to cytotoxicity, we investigated whether purified SNL glycoprotein is able to regulate protein kinase C (PKC) alpha activation and nuclear factor (NF)- kappaB activities in 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced tumor promotion, and whether it has an apoptosis-inducing effect in MCF-7 cells using western blot analysis. In addition, to elucidate the relationship between PKCalpha and NF-kappaB, inhibitory studies were performed with staurosporine (an inhibitor of phospholipid/calcium-dependent protein kinase) and pyrrolidine dithiocarbamate (an inhibitor of NF-kappaB activation). To verify induction of apoptosis by the SNL glycoprotein, we performed DNA fragmentation and nuclear staining assays using ethidium bromide and bisbenzamide H33342. The results in this study indicated that SNL glycoprotein induces apoptosis through modulation of PKCalpha and NF-kappaB activity in MCF-7 cells. In fact, SNL glycoprotein interfered with PKCalpha membrane translocation and inhibited NF-kappaB (p50) protein activity in MCF-7 cells stimulated with TPA (61.68 ng/mL, 100 nM) dose-dependently. Regarding the apoptotic-inducing effect, nucleosomal DNA fragmentation and nuclear staining by SNL glycoprotein in MCF-7 cells were shown. Collectively, the data demonstrate that SNL glycoprotein is a potential natural anticancer agent because of its ability to induce apoptosis in MCF-7 cells. PMID:15857213

  19. Iodination by stimulated human neutrophils. Studies on its stoichiometry, subcellular localization and relevance to microbial killing.

    PubMed Central

    Segal, A W; Garcia, R C; Harper, A M; Banga, J P

    1983-01-01

    Myeloperoxidase of phagocytic leucocytes is thought to utilize H2O2 to oxidize halides, which then react with and kill ingested microbes. This hypothesis was based largely on the incorporation of radiolabelled iodide into cells that had phagocytosed bacteria. The present studies investigated the stoichiometry of these reactions and the subcellular localization and electrophoretic pattern of the cellular components that became iodinated. 1. The stoichiometry of the reactions are such that only a small proportion (less than 0.3%) of the total oxygen consumed is utilized for iodination. Iodination after stimulation with the soluble stimulus phorbol myristate acetate (PMA), which is not known to involve the azurophil granules and their contained myeloperoxidase, was comparable with that occurring after bacterial ingestion. 2. Analytical subcellular fractionation of cells that had phagocytosed bacteria localized about 25% of the radioactivity to the membranes, and most of the residual radioactivity distributed with the bacteria and dense granules. In cells stimulated with PMA, more of the radioactivity was associated with the membranes, but about half was still associated with the dense granules. 3. Autoradiographs after dodecyl sulphate/polyacrylamide-gel electrophoresis of cells stimulated with opsonized bacteria gave a similar distribution of iodinated components to that obtained with cells that had been stimulated with PMA or iodinated with Iodogen. These patterns of iodination were very different from those obtained when bacteria alone were iodinated with Iodogen or myeloperoxidase and H2O2. Preparations in which bacteria had been phagocytosed did not show evidence of iodination of bacterial proteins or coating opsonins. Thus positive evidence for the iodination of bacteria has not been produced, and the role of iodination in the microbicidal process of neutrophils remains to be established. Images Fig. 6. Fig. 7. PMID:6303312

  20. Effects of activation of protein kinase C (PKC) on the hormonal stimulation and inhibition of cAMP formation in intact human platelets

    SciTech Connect

    Williams, K.A.; Haslam, R.J.

    1986-05-01

    Washed platelets, labelled by preincubation with (/sup 3/H)adenine and (/sup 32/P)P/sub i/, were studied in the presence of indomethacin, phosphocreatine and creatine phosphokinase to block thromboxane A/sub 2/ formation and inhibitory effects of released ADP. Addition of phorbol 12-myristate 13-acetate (PMA) or 1,2-dioctanoyl-glycerol (diC/sub 8/) decreased the initial rate of accumulation of (/sup 3/H)cAMP observed with PGE/sub 1/ and 3-isobutyl 1- methylxanthine. Maximal decreases of 31% (1 ..mu..M PMA) and 42% (100 ..mu..M diC/sub 8/) were obtained. Also, the inhibition of (/sup 3/H)cAMP formation by epinephrine (5 ..mu..M) was decreased from 68% to 16% and 31% by 1..mu..M PMA and 100 ..mu..M diC/sub 8/, respectively. The effects of increasing concentrations of PMA and diC/sub 8/ on the stimulation of (/sup 3/H)cAMp formation by PGE/sub 1/ and on the inhibitory action of epinephrine correlated with increases in /sup 32/P incorporation into the major substrate of PKC (P47) and into two other polypeptides (P41 and P20). These results suggested that activation of PKC might explain the failure of some aggregating agents (e.g. PAF and vasopressin) to inhibit adenylate cyclase in intact platelets, although they are inhibitory with isolated membranes. However, comparison of the effects of PMA and these aggregating agents on the phosphorylation of platelet polypeptides indicated that activation of PKC by aggregating agents is inadequate to block their inhibitory effects on adenylate cyclase, when PGE/sub 1/ is present.

  1. Mesoxalaldehyde acetals

    SciTech Connect

    Gordeeva, G.N.; Kalashnikov, S.M.; Popov, Yu.N.; Kruglov, E.A.; Imashev, U.B.

    1987-11-10

    The treatment of methylglyoxal acetals by alkyl nitrites in the presence of the corresponding aliphatic alcohols and hydrochloric acid leads to the formation of linear mesoxalaldehyde acetals, whose structure was established by NMR spectroscopy and mass spectrometry. The major pathways for the decomposition of these molecules upon electron impact were established.

  2. Protein kinase C modulates cytosolic free calcium by stimulating calcium pump activity in Jurkat T cells.

    PubMed

    Balasubramanyam, M; Gardner, J P

    1995-12-01

    Although protein kinase C (PKC) activation has been shown to inhibit Ca2+ influx in T lymphocytes, the role of PKC on Ca2+ sequestration or extrusion processes has not been fully explored. We examined the effect of CD3 stimulation and PKC activators on cytosolic Ca2+ (Ca2+i) extrusion and 45Ca2+ efflux in human leukemic Jurkat T cells. Treatment of Fura-2 loaded cells with phorbol 12-myristate 13-acetate (PMA) or thymeleatoxin (THYM) resulted in a decrease in Ca2+i both in the presence and absence of extracellular Ca2+, whereas inactive phorbol esters had no effect. PKC activators added at the peak of a Ca2+i transient induced by anti-CD3 mAb, ionomycin or thapsigargin (TG) stimulated the rate and extent of return of Ca2+i to basal levels by 17-53%. PKC stimulation of the Ca2+i decline was not enhanced by the presence of Na+, indicating that PKC activators increase Ca2+ pump activity rather than a Na+/Ca2+ exchange mechanism. As CD3 receptor activation enhanced the Ca2+i decline in TG-treated cells, antigen-mediated activation of phospholipase C (PLC) signaling includes enhanced Ca2+ extrusion at the plasma membrane. The effect of PKC activators on parameters of Ca2+i extrusion were further explored. PMA significantly increased the rate of Ca2+ extrusion in TG-treated cells from 0.28 +/- 0.02 to 0.35 +/- 0.03 s-1 (mean +/- SEM) and stimulated the initial rate of 45Ca2+ efflux by 69% compared to inactive phorbol ester treated cells. The effects of PKC activation on the Ca2+i decline were eliminated by PKC inhibitors, PKC down regulation (24 h PMA pretreatment), ATP-depletion and conditions that inhibited the Ca2+ pump. In contrast, pretreatment of cells with okadaic acid enhanced the PMA-stimulated response. We suggest that Jurkat T cells contain a PKC-sensitive Ca2+ extrusion mechanism likely to be the Ca2+ pump. In lymphocytes, receptor/PLC-linked PKC activation modulates Ca2+i not only by inhibiting Ca2+ influx but also by stimulating plasma membrane Ca2+i

  3. 21 CFR 814.45 - Denial of approval of a PMA.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.45 Denial of approval of a PMA. (a) FDA may issue an order denying approval of a PMA if the applicant fails to follow the... information before the agency, FDA determines that any of the grounds for denying approval of a PMA...

  4. 21 CFR 814.45 - Denial of approval of a PMA.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.45 Denial of approval of a PMA. (a) FDA may issue an order denying approval of a PMA if the applicant fails to follow the... information before the agency, FDA determines that any of the grounds for denying approval of a PMA...

  5. 21 CFR 814.45 - Denial of approval of a PMA.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.45 Denial of approval of a PMA. (a) FDA may issue an order denying approval of a PMA if the applicant fails to follow the... information before the agency, FDA determines that any of the grounds for denying approval of a PMA...

  6. Contraction of rat thoracic aorta strips induced by phorbol 12-myristate 13-acetate

    SciTech Connect

    Itoh, H.; Lederis, K.

    1987-02-01

    Phorbol 12-myristate 13-acetate (PMA) induced a slow and progressive increase in tension of rat thoracic aorta strips in the presence of extracellular CaS . Complete relaxation could not be obtained in CaS -free buffer containing 1 mM ethyleneglycol-bis(US -aminoethylether)-N,N'-tetraacetic acid (EGTA) and 10 X M PMA. In the absence of extracellular CaS , PMA (10 X M) induced a small but sustained contraction which was not altered by the addition of another 2 mM EGTA and 3 x 10 V M verapamil. Papaverine (10 U M) relaxed the PMA-induced contraction to the base line, but phentolamine (10 V M), cyproheptadine (10 V M), atropine (10 V M) and tetrodotoxine (10 W M) did not change the contraction. CaS -depleted muscle strips, prepared by four repeated applications of 10 X M norepinephrine in CaS -free buffer, were contracted by 10 X M PMA, but at a lower maximum tension than nontreated strips. The action of PMA on rat aorta strips in CaS -free buffer did not require the presence of the adventitial layer or endothelial cells. These results suggest that PMA may induce activation of protein kinase C and smooth muscle contraction in the absence of extracellular CaS , without an increase in myoplasmic CaS .

  7. Transfected adenosine A1 receptor-mediated modulation of thrombin-stimulated phospholipase C and phospholipase A2 activity in CHO cells.

    PubMed

    Dickenson, J M; Hill, S J

    1997-02-19

    Thrombin receptor activation in Chinese hamster ovary (CHO) cells stimulates the hydrolysis of inositol phospholipids and the release of arachidonic acid. Our previous studies have shown that activation of the human transfected adenosine A1 receptor in CHO cells (CHO-A1) potentiates the accumulation of inositol phosphates elicited by endogenous P2U purinoceptors and CCKA receptors. In this study we have investigated whether adenosine A1 receptor activation can modulate thrombin-stimulated arachidonic acid release and/or inositol phospholipid hydrolysis in CHO-A1 cells. Thrombin stimulated [3H]arachidonic acid release and total [3H]inositol phosphate accumulation in CHO-A1 cells. Both these responses to thrombin were were insensitive to pertussis toxin. The protein kinase C activator, phorbol 12-myristate 13-acetate (PMA), potentiated thrombin-stimulated [3H]arachidonic acid. In marked contrast, PMA inhibited thrombin-stimulated [3H]inositol phosphate accumulation. The selective protein kinase C inhibitor Ro 31-8220 (3-¿1-[3-(2-isothioureido)propyl] indol-3-yl¿-4-(1-methylindol-3-yl)-3-pyrrolin-2,5-dione) had no effect on thrombin-stimulated [3H]arachidonic acid release but reversed the potentiation of thrombin-stimulated [3H]arachidonic acid release elicited by PMA. The selective adenosine A1 receptor agonist N6-cyclopentyladenosine (CPA) augmented the release of [3H]arachidonic acid produced by thrombin. Co-activation of the adenosine A1 receptor also potentiated thrombin-stimulated [3H]inositol phosphate accumulation. The synergistic interactions between the adenosine A1 receptor and thrombin were abolished in pertussis-toxin-treated cells. The potentiation of [3H]arachidonic acid release by CPA was blocked by the protein kinase C inhibitors Ro 31-8220 and GF 109203X (3-[1-[3-(dimethylamino)propyl]-1 H-indol-3-yl]-4-(1 H-indol-3-yl)- 1H-pyrrole-2,5-dione). In conclusion, thrombin receptor activation in CHO-A1 cells stimulates the accumulation of [3H

  8. A Comparison Between Phorbol 12 Myristate 13 Acetate and Phorbol 12, 13 Dibutyrate in Human Melanocyte Culture

    PubMed Central

    Padma, Divya

    2016-01-01

    Introduction Melanocyte culture is an integral part of the studies of skin biology and cosmetic applications. After the introduction of selective medium for the culture of human melanocyte using Phorbol 12-myristate13-acetate (PMA) in 1982, a lot of methods of culturing were tried but till date PMA is a preferred mitogen because of its cost effectiveness compared to growth factors. We have tried to preliminarily evaluate the efficacy of another phorbol ester, Phorbol 12, 13-dibutyrate (PDBu) in melanocyte culture because of its less hydrophobic nature compared to PMA. This property minimizes the trace amount of mitogen in cell culture after washing off and hence does not interfere in other biological assays. Aim To evaluate the differences in the melanocyte survival rate, morphology and mitotic index when grown in media supplemented with PMA and PDBu. Materials and Methods Foreskins were collected from children undergoing circumcision. Epidermal cells were isolated from foreskin and cultured using PMA and PDBu. Melanocytes in culture were monitored for the better establishment and documented. In proliferative assay, melanocytes were treated with PMA and PDBu for 24, 48 and 72 hours and proliferation was measured using 3-(4,5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay method. Results When cultured, melanocytes acquired proliferative status and bipolar morphology quicker in PDBu medium than in PMA medium. Keratinocytes survived as contamination in PMA medium whereas PDBu medium had minimal keratinocytes. MTT assay showed that PDBu has higher proliferative induction capacity than PMA. In even lower concentration of PDBu in medium, melanocytes survived till 72 hours without significant cell loss in compared to PMA medium. Conclusion PDBu can be a valuable replacement for PMA in human melanocyte culture. Higher proliferation induction, unfavourable to keratinocyte survival and less hydrophobicity make PDBu a promising alternative for quicker

  9. Demonstration of calcium-dependent phospholipase A2 activity in membrane preparation of rabbit neutrophils. Absence of activation by fMet-Leu-Phe, phorbol 12-myristate 13-acetate and A-kinase.

    PubMed Central

    Matsumoto, T; Tao, W; Sha'afi, R I

    1988-01-01

    The presence of a phospholipase A2 (PLA2) activity in rabbit neutrophil membrane preparation that is able to release [1-14C]oleic acid from labelled Escherichia coli has been demonstrated. The activity is critically dependent on the free calcium concentration and marginally stimulated by GTP gamma S. More than 80% of maximal activity is reached at 10 microM-Ca2+. The chemotactic factor, fMet-Leu-Phe, does not stimulate the PLA2 activity in this membrane preparation. Pretreatment of the membrane preparation, under various experimental conditions, or intact cells, before isolation of the membrane with phorbol 12-myristate 13-acetate (PMA), does not affect PLA2 activity. Addition of the catalytic unit of cyclic AMP-dependent kinase to membrane preparation has no effect on PLA2 activity. Pretreatment of the intact neutrophil with dibutyryl-cAMP before isolation of the membrane produces a small but consistent increase in PLA2 activity. The activity of PLA2 in membrane isolated from cells treated with the protein kinase inhibitor 1-(5-isoquinolinesulphonyl)-2-methyl piperazine dihydrochloride (H-7) is significantly decreased. Furthermore, although the addition of PMA to intact rabbit neutrophils has no effect on the release of [3H]arachidonic acid from prelabelled cells, it potentiates significantly the release produced by the calcium ionophore A23187. This potentiation is not due to an inhibition of the acyltransferase activity. H-7 inhibits the basal release of arachidonic acid but does not inhibit the potentiation by PMA. These results suggest several points. (1) fMet-Leu-Phe does not stimulate PLA2 directly, and its ability to release arachidonic acid in intact neutrophils is mediated through its action on phospholipase C. (2) The potentiating effect of PMA on A23187-induced arachidonic acid release is most likely due to PMA affecting either the environment of PLA2 and/or altering the organization of membrane phospholipids in such a way as to increase their

  10. Bactericidal capacity of phorbol myristate acetate-treated human polymorphonuclear leukocytes.

    PubMed Central

    Wang-Iverson, P; Pryzwansky, K B; Spitznagel, J K; Cooney, M H

    1978-01-01

    Thus far, the functional capacity of phorbol myristate acetate- (PMA)-treated human polymorphonuclear leukocytes has been undefined. PMA induced exocytosis of lactoferrin, the specific granule marker, but not of myeloperoxidase, the azurophil granule marker. This phenomenon was demonstrated both biochemically and with fluorescent antibody conjugates. PMA-treated neutrophils contained virtually no specific granules when viewed by electron microscopy. Separation of the granule classes by linear sucrose density gradient centrifugation revealed the loss, from PMA-treated neutrophils, of lactoferrin and the specific granule (D20(20) = 1.89) band usually resolved from normal neutrophils. Cells treated with PMA appeared to retain those functions normally associated with intraleukocytic microbicidal action. The hexose monophosphate shunt activated by phagocytic challenge was present in PMA-treated neutrophils. As demonstrated by electron microscopy, the azurophil granules of these cells appeared intact, and they retained the capacity for degranulation with translocation of myeloperoxidase to the site of phagocytized Escherichia coli. The PMA-treated neutrophils also remained capable of degrading the ingested microorganisms. PMA-treated neutrophils exhibited a decrease in phagocytic ability at all levels of bacterial challenge. In the presence of a high multiplicity of bacteria they demonstrated an impairment in killing. These same cells were able to kill low multiplicities of E. coli as well as control cells. It thus appeared that the loss of the specific granules, plus other undefined PMA-induced alterations, impaired neither the viability of these neutrophils nor their killing ability in the presence of a modest phagocytic challenge. Images PMID:730386

  11. Observation of phagocytosis of fullerene nanowhiskers by PMA-treated THP-1 cells

    NASA Astrophysics Data System (ADS)

    Nudejima, S.; Miyazawa, K.; Okuda-Shimazaki, J.; Taniguchi, A.

    2009-04-01

    Phorbol 12-myristate 13-acetate (PMA)-treated THP-1 cells (macrophage-like cells) were exposed to the C60 fullerene nanowhiskers (C60 NWs) with an average length of about 6.0 μm and an average diameter of about 660 run and observed with an inverted optical phase-contrast microscope for 48 h. The C60 NWs were well and stably dispersed onto the dishes of culture medium during the observation. The number of cells that internalised C60 NWs gradually increased after the exposure to C60 NWs. But no alteration of cellular morphology was observed compared to the control group without exposure to C60 NWs during this period in this pilot study.

  12. Ethyl acetate

    Integrated Risk Information System (IRIS)

    Ethyl acetate ; CASRN 141 - 78 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  13. Phenylmercuric acetate

    Integrated Risk Information System (IRIS)

    Phenylmercuric acetate ; CASRN 62 - 38 - 4 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinog

  14. Vinyl acetate

    Integrated Risk Information System (IRIS)

    Vinyl acetate ; CASRN 108 - 05 - 4 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  15. Ammonium acetate

    Integrated Risk Information System (IRIS)

    Ammonium acetate ; CASRN 631 - 61 - 8 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic

  16. Thallium acetate

    Integrated Risk Information System (IRIS)

    Jump to main content . Integrated Risk Information System Recent Additions | Contact Us Search : All EPA IRIS • You are here : EPA Home • Research • Environmental Assessment • IRIS • IRIS Summaries Redirect Page As of September 30 , 2009 , the assessment summary for Thallium acetate is included in t

  17. Piperine inhibits PMA-induced cyclooxygenase-2 expression through downregulating NF-κB, C/EBP and AP-1 signaling pathways in murine macrophages.

    PubMed

    Kim, Hyung Gyun; Han, Eun Hee; Jang, Woo-Seok; Choi, Jae Ho; Khanal, Tilak; Park, Bong Hwan; Tran, Thu Phuong; Chung, Young Chul; Jeong, Hye Gwang

    2012-07-01

    Piperine is a major component of black (Piper nigrum Linn) and long (Piper longum Linn) peppers, and is widely used as a traditional food and medicine. It also exhibits a variety of biological activities, which include antioxidant, anti-tumor and anti-pyretic properties. In the present study, we investigated the inhibitory effects of piperine on phorbol 12-myristate 13-acetate (PMA)-induced cyclooxygenase-2 (COX-2) gene expression and analyzed the molecular mechanism of its activity in murine RAW 264.7 macrophages. Piperine dose-dependently decreased PMA-induced COX-2 expression and PGE(2) production, as well as COX-2 promoter-driven luciferase activity. Transient transfections utilizing COX-2 promoter deletion constructs and COX-2 promoter constructs, in which specific enhancer elements were mutagenized, revealed that the nuclear factor-κB (NF-κB), CCAAT/enhancer binding protein (C/EBP) and activator protein-1 (AP-1), were the predominant contributors to the effects of piperine. In addition, piperine inhibited PMA-induced NF-κB, C/EBP and c-Jun nuclear translocation. Furthermore, piperine significantly inhibited PMA-induced activation of the Akt and ERK. These findings demonstrate that piperine effectively attenuates COX-2 production, and provide further insight into the signal transduction pathways involved in the anti-inflammatory effects of piperine. PMID:22542552

  18. 14 CFR 45.15 - Marking requirements for PMA articles, TSO articles, and Critical parts.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Marking requirements for PMA articles, TSO articles, and Critical parts. 45.15 Section 45.15 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... Articles § 45.15 Marking requirements for PMA articles, TSO articles, and Critical parts. (a) PMA...

  19. 14 CFR 45.15 - Marking requirements for PMA articles, TSO articles, and Critical parts.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Marking requirements for PMA articles, TSO articles, and Critical parts. 45.15 Section 45.15 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... Articles § 45.15 Marking requirements for PMA articles, TSO articles, and Critical parts. (a) PMA...

  20. 14 CFR 45.15 - Marking requirements for PMA articles, TSO articles, and Critical parts.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Marking requirements for PMA articles, TSO articles, and Critical parts. 45.15 Section 45.15 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... Articles § 45.15 Marking requirements for PMA articles, TSO articles, and Critical parts. (a) PMA...

  1. 21 CFR 814.47 - Temporary suspension of approval of a PMA.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... (CONTINUED) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.47 Temporary... the original PMA, as well as any PMA supplement(s), for a medical device. (2) FDA will issue an order... continued distribution of the device would cause serious, adverse health consequences or death....

  2. 21 CFR 814.47 - Temporary suspension of approval of a PMA.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... (CONTINUED) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.47 Temporary... the original PMA, as well as any PMA supplement(s), for a medical device. (2) FDA will issue an order... continued distribution of the device would cause serious, adverse health consequences or death....

  3. 21 CFR 814.46 - Withdrawal of approval of a PMA.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.46 Withdrawal of approval of a PMA. (a) FDA may issue an order withdrawing approval of a PMA if, from any information available to the agency, FDA determines that: (1) Any of the grounds under section 515(e)(1) (A)-(G) of the...

  4. 21 CFR 814.46 - Withdrawal of approval of a PMA.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.46 Withdrawal of approval of a PMA. (a) FDA may issue an order withdrawing approval of a PMA if, from any information available to the agency, FDA determines that: (1) Any of the grounds under section 515(e)(1) (A)-(G) of the...

  5. 21 CFR 814.46 - Withdrawal of approval of a PMA.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.46 Withdrawal of approval of a PMA. (a) FDA may issue an order withdrawing approval of a PMA if, from any information available to the agency, FDA determines that: (1) Any of the grounds under section 515(e)(1) (A)-(G) of the...

  6. 21 CFR 814.40 - Time frames for reviewing a PMA.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Time frames for reviewing a PMA. 814.40 Section...) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.40 Time frames for reviewing a PMA. Within 180 days after receipt of an application that is accepted for filing and to...

  7. 21 CFR 814.40 - Time frames for reviewing a PMA.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Time frames for reviewing a PMA. 814.40 Section...) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.40 Time frames for reviewing a PMA. Within 180 days after receipt of an application that is accepted for filing and to...

  8. 21 CFR 814.47 - Temporary suspension of approval of a PMA.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Temporary suspension of approval of a PMA. 814.47... (CONTINUED) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.47 Temporary suspension of approval of a PMA. (a) Scope. (1) This section describes the procedures that FDA will follow...

  9. Novel post-translational incorporation of tyrosine in PMA-activated polymorphonuclear leukocytes (PMN)

    SciTech Connect

    Nath, J.; Oliver, C.; Ohno, Y.; Gallin, J.I.

    1986-03-05

    During studies undertaken to determine whether stimulation of tubulin tyrosinolation occurs in PMA-activated PMN, a distinctly different and novel post-translational incorporation of tyrosine into multiple PMN proteins was observed. The reaction also occurred in organelle-depleted neutrophil cytoplasts and was highly exaggerated in organelle-enriched karyogranuloplasts. The incorporation was specific for tyrosine, did not require extracellular Ca/sup 2 +/ and was inhibited in the presence of a variety of reducing agents, intracellular scavengers of oxygen radicals and inhibitors of peroxidase-mediated reactions. The PMA-induced incorporation of tyrosine was completely absent in PMN from patients with chronic granulomatous disease, but occurred normally in PMN of a patient with myeloperoxidase deficiency. Moreover, the incorporation of tyrosine was blocked by N-acetyl-L-tyrosine but not by phenylalanine suggesting a requirement for the phenolic group. A two-fold increase in stable protein carbonyl derivatives was demonstrated suggesting an increased oxidative modification of the proteins. SDS urea PAGE and reversed phase HPLC did not reveal any detectable changes in the extent of protein cross-linking. The PMN tyrosine pool was approximately 900 ..mu..M and yet only 1 ..mu..M tyrosine was added in these experiments. The functional significance of this reaction is not yet clear.

  10. Decreased cholinergic stimulation of insulin secretion by islets from rats fed a low protein diet is associated with reduced protein kinase calpha expression.

    PubMed

    Ferreira, Fabiano; Filiputti, Eliane; Arantes, Vanessa C; Stoppiglia, Luis F; Araújo, Eliana P; Delghingaro-Augusto, Viviane; Latorraca, Márcia Q; Toyama, Marcos H; Boschero, Antonio C; Carneiro, Everardo M

    2003-03-01

    Undernutrition has been shown to affect the autonomic nervous system, leading to permanent alterations in insulin secretion. To understand these interactions better, we investigated the effects of carbamylcholine (CCh) and phorbol 12-myristate 13-acetate (PMA) on insulin secretion in pancreatic islets from rats fed a normal (17%; NP) or low (6%; LP) protein diet for 8 wk. Isolated islets were incubated for 1 h in Krebs-bicarbonate solution containing 8.3 mmol glucose/L, with or without PMA (400 nmol/L) and CCh. Increasing concentrations of CCh (0.1-1000 micro mol/L) dose dependently increased insulin secretion by islets from both groups of rats. However, insulin secretion by islets from rats fed the NP diet was significantly higher than that of rats fed the LP diet, and the dose-response curve to CCh was shifted to the right in islets from rats fed LP with a 50% effective concentration (EC(50)) of 2.15 +/- 0.7 and 4.64 +/- 0.1 micro mol CCh/L in islets of rats fed NP and LP diets, respectively (P < 0.05). PMA-induced insulin secretion was higher in islets of rats fed NP compared with those fed LP. Western blotting revealed that the protein kinase (PK)Calpha and phospholipase (PL)Cbeta(1) contents of islets of rats fed LP were 30% lower than those of islets of rats fed NP (P < 0.05). In addition, PKCalpha mRNA expression was reduced by 50% in islets from rats fed LP. In conclusion, a reduced expression of PKCalpha and PLCbeta(1) may be involved in the decreased insulin secretion by islets from LP rats after stimulation with CCh and PMA. PMID:12612139

  11. CREB-regulated transcription co-activator family stimulates promoter II-driven aromatase expression in preadipocytes.

    PubMed

    Samarajeewa, Nirukshi U; Docanto, Maria M; Simpson, Evan R; Brown, Kristy A

    2013-08-01

    The dramatically increased prevalence of breast cancer after menopause is of great concern and is correlated with elevated local levels of estrogens. This is mainly due to an increase in aromatase expression driven by its proximal promoter II (PII). We have previously demonstrated that the CREB co-activator CRTC2 binds directly to PII and stimulates its activity via mechanisms involving LKB1-AMPK in response to prostaglandin E(2) (PGE(2)). There are three members of the CRTC family (CRTC1-3) and this study aimed to characterize the role of other CRTCs in the activation of aromatase PII. The expression and subcellular localization of CRTCs were examined in preadipocytes using qPCR and immunofluorescence. Under basal conditions, CRTC1 expression was the lowest, whereas CRTC3 transcripts were present at higher levels. Basally, CRTC2 and CRTC3 were mainly cytoplasmic and PGE(2) caused their nuclear translocation. Reporter assays and chromatin immunoprecipitation (ChIP) were performed to assess the effect of CRTCs on PII activity and binding. Basal PII activity was significantly increased with all CRTCs. Forskolin (FSK)/phorbol 12-myristate 13-acetate (PMA), to mimic PGE(2), resulted in a further significant increase in PII activity with all CRTCs, with CRTC2 and CRTC3 having greater effects. This was consistent with ChIP data showing an increased binding of CRTCs to PII with FSK/PMA. Moreover, gene silencing of CRTC2 and CRTC3 significantly reduced the FSK/PMA-mediated stimulation of aromatase activity. Interestingly, CRTCs acted cooperatively with CREB1 to increase PII activity, and both CREs were found to be essential for the maximal induction of PII activity by CRTCs. Phosphorylation of CRTC2 at its AMPK target site, Ser 171, dictated its subcellular localization, and the activation of aromatase PII in preadipocytes. In conclusion, this study demonstrates that aromatase regulation in primary human breast preadipocytes involves more than one CRTC.

  12. Stimulation of Ebola virus production from persistent infection through activation of the Ras/MAPK pathway.

    PubMed

    Strong, James E; Wong, Gary; Jones, Shane E; Grolla, Allen; Theriault, Steven; Kobinger, Gary P; Feldmann, Heinz

    2008-11-18

    Human infections with Ebola virus (EBOV) result in a deadly viral disease known as Ebola hemorrhagic fever. Up to 90% of infected patients die, and there is no available treatment or vaccine. The sporadic human outbreaks are believed to result when EBOV "jumps" from an infected animal to a person and is subsequently transmitted between persons by direct contact with infected blood or body fluids. This study was undertaken to investigate the mechanism by which EBOV can persistently infect and then escape from model cell and animal reservoir systems. We report a model system in which infection of mouse and bat cell lines with EBOV leads to persistence, which can be broken with low levels of lipopolysaccharide or phorbol-12-myristate-13-acetate (PMA). This reactivation depends on the Ras/MAPK pathway through inhibition of RNA-dependent protein kinase and eukaryotic initiation factor 2alpha phosphorylation and occurs at the level of protein synthesis. EBOV also can be evoked from mice 7 days after infection by PMA treatment, indicating that a similar mechanism occurs in vivo. Our findings suggest that EBOV may persist in nature through subclinical infection of a reservoir species, such as bats, and that appropriate physiological stimulation may result in increased replication and transmission to new hosts. Identification of a presumptive mechanism responsible for EBOV emergence from its reservoir underscores the "hit-and-run" nature of the initiation of human and/or nonhuman primate EBOV outbreaks and may provide insight into possible countermeasures to interfere with transmission. PMID:18981410

  13. Mechanism of interferon-gamma production by monocytes stimulated with myeloperoxidase and neutrophil extracellular traps.

    PubMed

    Yamaguchi, Rui; Kawata, Jin; Yamamoto, Toshitaka; Ishimaru, Yasuji; Sakamoto, Arisa; Ono, Tomomichi; Narahara, Shinji; Sugiuchi, Hiroyuki; Hirose, Eiji; Yamaguchi, Yasuo

    2015-08-01

    Neutrophil extracellular traps (NETs) have an important role in antimicrobial innate immunity and release substances that may modulate the immune response. We investigated the effects of soluble factors from NETs and neutrophil granule proteins on human monocyte function by using the Transwell system to prevent cell-cell contact. NET formation was induced by exposing human neutrophils to phorbol myristate acetate (PMA). When monocytes were incubated with PMA alone, expression of interleukin (IL)-4, IL-6, IL-8, and tumor necrosis factor (TNF)-alpha mRNA was upregulated, but IL-10, IL-12, and interferon (IFN)-gamma mRNA were not detected. Incubation of monocytes with NETs enhanced the expression of IL-10 and IFN-gamma mRNA, but not IL-12 mRNA. Myeloperoxidase stimulated IFN-gamma production by monocytes in a dose-dependent manner. Both a nuclear factor-kappaB inhibitor (PDTC) and an intracellular calcium antagonist (TMB-8) prevented upregulation of IFN-gamma production. Neither a combined p38alpha and p38beta inhibitor (SB203580) nor an extracellular signal-regulated kinase inhibitor (PD98059) suppressed IFN-gamma production. Interestingly, a combined p38gamma and p38delta inhibitor (BIRB796) significantly decreased IFN-gamma production. These findings suggest that myeloperoxidase induces IFN-gamma production by monocytes via p38gamma/delta mitogen-activated protein kinase.

  14. Large scale production and purification of human IL-2 from buffy coat lymphocytes stimulated with 12-O-tetradecanoylphorbol 13-acetate and calcium ionophore A23187.

    PubMed

    Grote, W; Klaar, J; Mühlradt, P F; Monner, D A

    1987-10-23

    Methods for the production of high titers of interleukin-2 (IL-2) from human buffy coat lymphocytes, and subsequent purification of the IL-2 are described. 50 buffy coats containing 1 X 10(11) leukocytes were first depleted of erythrocytes by batchwise leukapheresis using a Haemonetics model 15 blood wash centrifuge. Further lymphocyte enrichment was achieved using a one-step sedimentation in the presence of hydroxyethyl starch, which produced suspensions of more than 90% lymphocytes. This degree of lymphocyte purity was important since phagocytes were inhibitory to 12-O-tetradecanoylphorbol 13-acetate/calcium ionophore (TPA/A23187)-induced IL-2 production when their concentration exceeded 15% of the total cells. Cell culture was performed in stirred fermenters. Using TPA/A23187 induction, up to 500 micrograms of IL-2 per liter were produced. The IL-2 was purified by absorption from the supernatants onto controlled pore glass and elution with 50% ethylene glycol, followed by Fractogel chromatography, and then preparative high-performance liquid chromatography (HPLC) using an RP-6 column and elution with a gradient of n-propanol. A final HPLC rechromatography step using an analytical RP-6 column gave a homogeneous preparation with specific activity of 1.2 X 10(7) U/mg and a recovery from the starting supernatant of 22%.

  15. Epidermal growth factor stimulates the disruption of gap junctional communication and connexin43 phosphorylation independent of 12-0-tetradecanoylphorbol 13-acetate-sensitive protein kinase C: the possible involvement of mitogen-activated protein kinase.

    PubMed

    Kanemitsu, M Y; Lau, A F

    1993-08-01

    We previously reported that epidermal growth factor (EGF) induced the disruption of gap junctional communication (gjc) and serine phosphorylation of connexin43 (Cx43) in T51B rat liver epithelial cells. However, the cascade of events linking EGF receptor activation to these particular responses have not been fully characterized. Furthermore, the serine kinase(s) acting directly on Cx43 remain unidentified. In the current study, we demonstrate that downmodulation of 12-0-tetradecanoylphorbol 13-acetate (TPA)-sensitive protein kinase C (PKC) activity does not affect EGF's ability to reduce junctional permeability or phosphorylate Cx43 in T51B cells. EGF in the presence or absence of chronic TPA treatment stimulated marked increases in Cx43 phosphorylation on numerous sites as determined by two-dimensional tryptic phosphopeptide mapping. Computer-assisted sequence analysis of Cx43 identified several protein kinase phosphorylation consensus sites including two sites for mitogen-activated protein (MAP) kinase. EGF stimulated activation of MAP kinase in a time- and dose-dependent manner where the kinetics of kinase activity corroborated its possible involvement in mediating EGF's effects. Moreover, purified MAP kinase directly phosphorylated Cx43 on serine residues in vitro. Two-dimensional tryptic and chymotryptic phosphopeptide mapping demonstrated that the in vitro phosphopeptides represented a specific subset of the in vivo phosphopeptides produced in response to EGF after chronic TPA treatment. Therefore, EGF-induced disruption of gjc and phosphorylation of Cx43 may be mediated in part by MAP kinase in vivo.

  16. RAS is required for epidermal growth factor-stimulated arachidonic acid release in rat-1 fibroblasts.

    PubMed

    Warner, L C; Hack, N; Egan, S E; Goldberg, H J; Weinberg, R A; Skorecki, K L

    1993-12-01

    Previous studies have provided suggestive evidence for an interaction between ras activation and signalling pathways involved in agonist-stimulated arachidonic acid release in a variety of cell systems. In order to clarify this interaction, we have measured epidermal growth factor (EGF)-stimulated arachidonic acid release in rat-1 fibroblasts transfected with the N-17 dominant negative mutation of ras. Cells transfected with the N-17 ras mutant, display a markedly attenuated arachidonic acid-release response to EGF, compared to sham-transfected and non-transfected cells. In contrast, the response to phorbol myristate acetate (PMA) was not attenuated in the N-17-mutant expressing cells. No differences were detected between sham-transfected and N-17 mutant expressing cells in levels of immunodetectable EGF receptor, cytosolic phospholipase A2 or mitogen-activated protein (MAP) kinase. Attenuation of EGF-stimulated arachidonic acid release in the N-17 mutant expressing cells, was accompanied by a marked diminution in EGF-stimulated tyrosine phosphorylation of MAP kinase. We conclude that the signalling pathway involved in epidermal growth factor-stimulated arachidonic acid release is similar to the signalling pathway for mitogenic responses to epidermal growth factor and requires ras activation, likely followed by a downstream cascade of kinases eventuating in MAP kinase activation.

  17. GnRH agonist Lupron (leuprolide acetate) pre-treatments prevent ovulation in response to gonadotropin stimulation in the clouded leopard (Neofelis nebulosa).

    PubMed

    Pelican, Katharine M; Wildt, David E; Howard, Jo Gayle

    2006-10-01

    In many species, controlling the ovary prior to induction of ovulation improves the success of ovarian response and artificial insemination (AI). We assessed the impact of suppression of estrus with the GnRH agonist, Lupron, on ovarian sensitivity to equine chorionic gonadotropin (eCG) and human chorionic gonadotropin (hCG) in the clouded leopard. Seven female clouded leopards were given two injections of Lupron (3.75 mg IM) 23 d apart, followed 44 d later by eCG and hCG. Daily fecal samples were collected from 60 d before Lupron to 60 d after hCG. Fecal metabolites of estrogen (E) and progesterone (P) were measured by radioimmunoassay. Lupron decreased (P < 0.05) the number of E peaks during Lupron treatment compared to pre-Lupron. All females had baseline E and six of seven (86%) had nadir P on day of eCG. Exogenous gonadotropins induced E elevations in all females. However, mean E in the gonadotropin-provoked estrus was decreased (P < 0.05) compared to pre-Lupron estrous periods. Only one of seven (14%) females ovulated after eCG/hCG. In conclusion, estrous cycle control with Lupron resulted in predictable ovarian suppression prior to gonadotropin stimulation but altered ovarian sensitivity by an as yet unknown mechanism so that ovulation was inhibited, even when using a proven exogenous gonadotropin protocol.

  18. Reduced response of splenocytes after mitogen-stimulation in the prion protein (PrP) gene-deficient mouse: PrPLP/Doppel production and cerebral degeneration

    SciTech Connect

    Kim, Chi-Kyeong; Hirose, Yuko; Sakudo, Akikazu; Takeyama, Natsumi; Kang, Chung-Boo; Taniuchi, Yojiro; Matsumoto, Yoshitsugu; Itohara, Shigeyoshi; Sakaguchi, Suehiro; Onodera, Takashi . E-mail: aonoder@mail.ecc.u-tokyo.ac.jp

    2007-06-29

    Splenocytes of wild-type (Prnp {sup +/+}) and prion protein gene-deficient (Prnp {sup -/-}) mice were treated with various activation stimuli such as T cell mitogen concanavalin A (ConA), phorbol 12-myristate 13-acetate (PMA) + ionomycin (Io), or B cell mitogen lipopolysaccharide (LPS). Cellular prion protein (PrP{sup C}) expression was enhanced following ConA stimulation, but not PMA + Io or LPS in Prnp {sup +/+} splenocytes. Rikn Prnp {sup -/-} splenocytes elicited lower cell proliferations than Prnp {sup +/+} or Zrch I Prnp {sup -/-} splenocytes after LPS stimulation and showed sporadic nerve cells in the cerebral cortex and deeper structure. Around the degenerated nerve cells, mild vacuolation in the neuropil was observed. This neural alteration correlated well to the suppressed response of B cells in the spleen. The finding that discrete lesions within the central nervous systems induced marked modulation of immune function probably indicates the existence of a delicately balanced neural-endocrine network by PrP{sup C} and PrPLP/Doppel.

  19. Anti-Inflammatory and Analgesic Effects of Pyeongwisan on LPS-Stimulated Murine Macrophages and Mouse Models of Acetic Acid-Induced Writhing Response and Xylene-Induced Ear Edema

    PubMed Central

    Oh, You-Chang; Jeong, Yun Hee; Cho, Won-Kyung; Ha, Jeong-Ho; Gu, Min Jung; Ma, Jin Yeul

    2015-01-01

    Pyeongwisan (PW) is an herbal medication used in traditional East Asian medicine to treat anorexia, abdominal distension, borborygmus and diarrhea caused by gastric catarrh, atony and dilatation. However, its effects on inflammation-related diseases are unknown. In this study, we investigated the biological effects of PW on lipopolysaccharide (LPS)-mediated inflammation in macrophages and on local inflammation in vivo. We investigated the biological effects of PW on the production of inflammatory mediators, pro-inflammatory cytokines and related products as well as the activation of nuclear factor kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) in LPS-stimulated macrophages. Additionally, we evaluated the analgesic effect on the acetic acid-induced writhing response and the inhibitory activity on xylene-induced ear edema in mice. PW showed anti-inflammatory effects by inhibiting the production of nitric oxide (NO), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) and interleukin-1β (IL-1β). In addition, PW strongly suppressed inducible nitric oxide synthase (iNOS), a NO synthesis enzyme, induced heme oxygenase-1 (HO-1) expression and inhibited NF-κB activation and MAPK phosphorylation. Also, PW suppressed TNF-α, IL-6 and IL-1β cytokine production in LPS-stimulated peritoneal macrophage cells. Furthermore, PW showed an analgesic effect on the writhing response and an inhibitory effect on mice ear edema. We demonstrated the anti-inflammatory effects and inhibitory mechanism in macrophages as well as inhibitory activity of PW in vivo for the first time. Our results suggest the potential value of PW as an inflammatory therapeutic agent developed from a natural substance. PMID:25569097

  20. Monoclonal antibodies to a particulate superoxide-forming system stimulate a respiratory burst in intact guinea pig neutrophils.

    PubMed Central

    Berton, G; Rosen, H; Ezekowitz, R A; Bellavite, P; Serra, M C; Rossi, F; Gordon, S

    1986-01-01

    Monoclonal rat antibodies were produced against a subcellular preparation of phorbol 12-myristate 13-acetate (PMA)-stimulated guinea pig neutrophils that retains NADPH-oxidase activity. Two antibodies, 1A10.4 and IG4, were isolated that bind to a surface antigen restricted to guinea pig neutrophils from bone marrow and peritoneal exudate and to macrophages and that trigger a respiratory burst in neutrophils in the presence of cytochalasin B. Intact antibody 1A10.4, subclass IgG2c, can trigger superoxide anion release directly; F(ab')2 fragments of 1A10.4 and intact IG4 require further cross-linking by F(ab')2 fragments of anti-rat immunoglobulin antibody. Both antibodies recognize the same antigen, a proteolipid of apparent molecular mass 10 kDa. Immunoprecipitation of solubilized oxidase activity with 1A10.4 brings down this activity as part of a macromolecular complex. Surface expression of the antigen is increased on treatment of cells with both PMA and cytochalasin B. 1A10.4 also triggers release of the granule enzyme beta-glucuronidase. Triggering of a respiratory burst by the antibodies appears distinct from the PMA and fMet-Leu-Phe signalling systems. These studies indicate that the antigen defined by antibodies 1A10.4 and IG4 becomes associated with the superoxide anion-generating system of neutrophils but may play a more general role in signal transduction in phagocytic cells. Images PMID:3012541

  1. 1,25-dihydroxycholecalciferol-induced differentiation of myelomonocytic leukemic cells unresponsive to colony stimulating factors and phorbol esters

    SciTech Connect

    Bettens, F.; Schlick, E.; Farrar, W.; Ruscetti, F.

    1986-12-01

    The murine myelomonocytic leukemia cell line WEHI-3B D/sup +/, which differentiates in response to granulocyte colony stimulating factor (G-CSF), can also be induced to differentiate into monocyte-macrophages by phorbol myristate acetate (PMA) treatment, whereas the WEHI-3B D/sup -/ subline, which is unresponsive to G-CSF and PMA, can be induced to differentiate to granulocytes as well as monocytes by 1,25-dihydroxycholecalciferol (1,25-(OH)/sub 2/ D3), the biologically active metabolite of vitamin D3. A newly developed variant of the WEHI-3B D/sup +/ line, named WEHI-3B D/sup +/G, which was responsive to G-CSF but not to PMA, was also differentiated to granulocytes by 1,25-(OH)/sub 2/ D3. Although vitamin D3 has been reported to induce macrophage differentiation in responsive tumor cells, this is the first demonstration that 1,25-(OH)/sub 2/ D3 can induce granulocyte differentiation. In both differentiation pathways, cessation of cellular proliferation accompanies changes in morphologic and cytochemical properties of the cells. This suggests that leukemic cell lines unresponsive to differentiation agents acting at the cell surface retain their ability to differentiate in response to agents that do not act via the plasma membrane such as 1,25-(OH)/sub 2/ D3, which has cytosolic/nuclear receptors. These results suggest that low doses of 1,25-(OH)/sub 2/ D3 may be useful in combination with hemopoietic growth factors (CSFs) as therapeutic agent to induce leukemic cell differentiation in vivo.

  2. Regulation of urokinase-type plasminogen activator gene transcription by macrophage colony-stimulating factor.

    PubMed Central

    Stacey, K J; Fowles, L F; Colman, M S; Ostrowski, M C; Hume, D A

    1995-01-01

    The mouse urokinase-type plasminogen activator (uPA) gene was used as a model macrophage colony-stimulating factor 1 (CSF-1)-inducible gene to investigate CSF-1 signalling pathways. Nuclear run-on analysis showed that induction of uPA mRNA by CSF-1 and phorbol myristate acetate (PMA) was at the transcriptional level in bone marrow-derived macrophages. CSF-1 and PMA synergized strongly in the induction of uPA mRNA, showing that at least some components of CSF-1 action are mediated independently of protein kinase C. Promoter targets of CSF-1 signalling were investigated with NIH 3T3 cells expressing the human CSF-1 receptor (c-fms). uPA mRNA was induced in these cells by treatment with CSF-1, and a PEA3/AP-1 element at -2.4 kb in the uPA promoter was involved in this response. Ets transcription factors can act through PEA3 sequences, and the involvement of Ets factors in the induction of uPA was confirmed by use of a dominant negative Ets-2 factor. Expression of the DNA binding domain of Ets-2 fused to the lacZ gene product prevented CSF-1-mediated induction of uPA mRNA in NIH 3T3 cells expressing the CSF-1 receptor. Examination of ets-2 mRNA expression in macrophages showed that it was also induced synergistically by CSF-1 and PMA. In the macrophage cell line RAW264, the uPA PEA3/AP-1 element mediated a response to both PMA and cotransfected Ets-2. uPA promoter constructs were induced 60- to 130-fold by Ets-2 expression, and the recombinant Ets-2 DNA binding domain was able to bind to the uPA PEA3/AP-1 element. This work is consistent with a proposed pathway for CSF-1 signalling involving sequential activation of fms, ras, and Ets factors. PMID:7760840

  3. 21 CFR 814.40 - Time frames for reviewing a PMA.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Time frames for reviewing a PMA. 814.40 Section 814.40 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.40 Time frames...

  4. 21 CFR 814.44 - Procedures for review of a PMA.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.44 Procedures for review... effectiveness of the device, which was the basis for the order approving the PMA, including information about any adverse effects of the device on health, is available on the Internet and has been placed...

  5. 21 CFR 814.40 - Time frames for reviewing a PMA.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Time frames for reviewing a PMA. 814.40 Section 814.40 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.40 Time frames...

  6. 21 CFR 814.44 - Procedures for review of a PMA.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.44 Procedures for review... effectiveness of the device, which was the basis for the order approving the PMA, including information about any adverse effects of the device on health, is available on the Internet and has been placed...

  7. 21 CFR 814.40 - Time frames for reviewing a PMA.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Time frames for reviewing a PMA. 814.40 Section 814.40 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.40 Time frames...

  8. 21 CFR 814.44 - Procedures for review of a PMA.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.44 Procedures for review... detailed summary of information respecting the safety and effectiveness of the device, which was the basis for the order approving the PMA, including information about any adverse effects of the device...

  9. 21 CFR 814.45 - Denial of approval of a PMA.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.45 Denial of approval of a... of the following reasons: (1) The PMA contains a false statement of material fact; (2) The device's... to show that the device is safe for use under the conditions prescribed, recommended, or suggested...

  10. 21 CFR 814.45 - Denial of approval of a PMA.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.45 Denial of approval of a... of the following reasons: (1) The PMA contains a false statement of material fact; (2) The device's... to show that the device is safe for use under the conditions prescribed, recommended, or suggested...

  11. Polymethacrylic acid grafted psyllium (Psy- g-PMA): a novel material for waste water treatment

    NASA Astrophysics Data System (ADS)

    Kumar, Ranvijay; Sharma, Kaushlendra; Tiwary, K. P.; Sen, Gautam

    2013-03-01

    Polymethacrylic acid grafted psyllium (Psy- g-PMA) was synthesized by microwave assisted method, which involves a microwave irradiation in synergism with silver sulfate as a free radical initiator to initiate grafting reaction. Psy- g-PMA grades have been synthesized and characterized on structural basis (elemental analysis, FTIR spectroscopy, intrinsic viscosity study) as well as morphological and thermal studies, taking psyllium as reference. The effects of reaction time, amount of monomer and silver sulfate (free radical initiator) on grafting of PMA on psyllium backbone have been studied. It is observed that all the grades of Psy- g-PMA have higher intrinsic viscosities than that of psyllium. The best synthesized grade was Psy- g-PMA having intrinsic viscosity of 6.93 and 58 % grafting of PMA on the main polymer backbone. Further Psy- g-PMA applications as flocculants for waste water treatment have been investigated. Psy- g-PMA resulted in higher decrease in the flocculation parameters such as total dissolved solid or total solids compared to psyllium. Hence the result shows the possible application of grafted psyllium in wastewater treatment.

  12. An ethyl acetate fraction derived from Houttuynia cordata extract inhibits the production of inflammatory markers by suppressing NF-кB and MAPK activation in lipopolysaccharide-stimulated RAW 264.7 macrophages

    PubMed Central

    2014-01-01

    Background Houttuynia cordata Thunb. (Saururaceae) has been used in traditional medicine for treatment of inflammatory diseases. This study evaluated the anti-inflammatory effects of an ethyl acetate fraction derived from a Houttuynia cordata extract (HCE-EA) on the production of inflammatory mediators and the activation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPKs) in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Methods To measure the effects of HCE-EA on pro-inflammatory cytokine and inflammatory mediator’s expression in RAW 264.7 cells, we used the following methods: cell viability assay, Griess reagent assay, enzyme-linked immunosorbent assay, real-time polymerase chain reaction and western blotting analysis. Results HCE-EA downregulated nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor-α (TNF-α), and interleukin (IL-6) production in the cells, as well as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression. Furthermore, HCE-EA suppressed nuclear translocation of the NF-κB p65 subunit, which correlated with an inhibitory effect on IκBα (nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha) phosphorylation. HCE-EA also attenuated the activation of MAPKs (p38 and JNK). Conclusions Our results suggest that the anti-inflammatory properties of HCE-EA may stem from the inhibition of pro-inflammatory mediators via suppression of NF-κB and MAPK signaling pathways. PMID:25012519

  13. Raf-1 kinase possesses distinct binding domains for phosphatidylserine and phosphatidic acid. Phosphatidic acid regulates the translocation of Raf-1 in 12-O-tetradecanoylphorbol-13-acetate-stimulated Madin-Darby canine kidney cells.

    PubMed

    Ghosh, S; Strum, J C; Sciorra, V A; Daniel, L; Bell, R M

    1996-04-01

    Previous studies demonstrated that the cysteine-rich amino-terminal domain of Raf-1 kinase interacts selectively with phosphatidylserine (Ghosh, S., Xie, W. Q., Quest, A. F. G., Mabrouk, G. M., Strum, J. C., and Bell, R. M. (1994) J. Biol. Chem. 269, 10000-10007). Further analysis showed that full-length Raf-1 bound to both phosphatidylserine and phosphatidic acid (PA). Specifically, a carboxyl-terminal domain of Raf-1 kinase (RafC; residues 295 648 of human Raf-1) interacted strongly with phosphatidic acid. The binding of RafC to PA displayed positive cooperativity with Hill numbers between 3.3 and 6.2; the apparent Kd ranged from 4.9 +/- 0.6 to 7.8 +/- 0.9 mol % PA. The interaction of RafC with PA displayed a pH dependence distinct from the interaction between the cysteine-rich domain of Raf-1 and PA. Also, the RafC-PA interaction was unaffected at high ionic strength. Of all the lipids tested, only PA and cardiolipin exhibited high affinity binding; other acidic lipids were either ineffective or weakly effective. By deletion mutagenesis, the PA binding site within RafC was narrowed down to a 35-amino acid segment between residues 389 and 423. RafC did not bind phosphatidyl alcohols; also, inhibition of PA formation in Madin-Darby canine kidney cells by treatment with 1% ethanol significantly reduced the translocation of Raf-1 from the cytosol to the membrane following stimulation with 12-O-tetradecanoylphorbol-13-acetate. These results suggest a potential role of the lipid second messenger, PA, in the regulation of translocation and subsequent activation of Raf-1 in vivo.

  14. Active Oxygen Metabolites and Thromboxane in Phorbol Myristate Acetate Toxicity to the Isolated, Perfused Rat Lung.

    NASA Astrophysics Data System (ADS)

    Carpenter, Laurie Jean

    When administered intravenously or intratracheally to rats, rabbits and sheep, phorbol myristate acetate (PMA) produces changes in lung morphology and function are similar to those seen in humans with the adult respiratory distress syndrome (ARDS). Therefore, it is thought that information about the mechanism of ARDS development can be gained from experiments using PMA-treated animals. Currently, the mechanisms by which PMA causes pneumotoxicity are unknown. Results from other studies in rabbits and in isolated, perfused rabbit lungs suggest that PMA-induced lung injury is mediated by active oxygen species from neutrophils (PMN), whereas studies in sheep and rats suggest that PMN are not required for the toxic response. The role of PMN, active oxygen metabolites and thromboxane (TxA_2) in PMA-induced injury to isolated, perfused rat lungs (IPLs) was examined in this thesis. To determine whether PMN were required for PMA to produce toxicity to the IPL, lungs were perfused for 30 min with buffer containing various concentrations of PMA (in the presence or absence of PMN). When concentrations >=q57 ng/ml were added to medium devoid of added PMN, perfusion pressure and lung weight increased. When a concentration of PMA (14-28 ng/ml) that did not by itself cause lungs to accumulate fluid was added to the perfusion medium containing PMN (1 x 10 ^8), perfusion pressure increased, and lungs accumulated fluid. These results indicate that high concentrations of PMA produce lung injury which is independent of PMN, whereas injury induced by lower concentrations is PMN-dependent. To examine whether active oxygen species were involved in mediating lung injury induced by PMA and PMN, lungs were coperfused with the oxygen radical scavengers SOD and/or catalase. Coperfusion with either or both of these enzymes totally protected lungs against injury caused by PMN and PMA. These results suggest that active oxygen species (the hydroxyl radical in particular), mediate lung injury in

  15. Phorbol ester stimulates membrane association of protein kinase C and inhibits spontaneous Ca/sup 2 +/ dependent sarcoplasmic reticulum Ca/sup 2 +/ release in rat cardiac cells

    SciTech Connect

    Capogrossi, M.C.; Kaku, T.; Filburn, C.H.; Pelto, D.J.; Hansford, R.G.; Lakatta, E.G.

    1986-03-01

    Spontaneous oscillatory Ca/sup 2 +/ release from sarcoplasmic reticulum (SR) occurs in rat cardiac myocytes at hyperpolarized membrane potentials and is manifested as contractile waves (W). W frequency varies with SR functional status and cell Ca/sup 2 +/ loading. In myocyte suspensions (Hepes buffer, 37/sup 0/C (Ca/sup 2 +/) = 1.0mM) phorbol myristate acetate, PMA, (10/sup -7/ M) increased protein kinase C activity in membranes as a fraction of total (PKCAM) fivefold with a t 1/2 of < 30 sec (n = 3) and decreased W frequency in individual myocytes (n = 8). This effect varied directly and linearly with baseline W frequency, r = .94, p < .001). Dioctanoyl glycerol (10 ..mu.. M) had a similar effect on W. The PMA effect to decrease W frequency could be a direct one on SR or result from a reduction in cell Ca/sup 2 +/. The time course of PKCAM change is sufficiently rapid for it to mediate the effect on W. Thus, enhanced PKCAM may exert negative feedback control on Ca/sup 2 +/ mobilization during ..cap alpha..-adrenergic stimulation.

  16. Stimulation of Paramecium phagocytosis by phorbol ester and forskolin.

    PubMed

    Wyroba, E

    1987-09-01

    Phorbol ester (PMA) exerted a dose- and time- dependent stimulating effect on phagocytosis in axenic Paramecium aurelia. When cells were exposed to 200-800 nM PMA in the presence of latex beads, the phagocytic coefficient was enhanced 2.25 to 3.14 times, during 10 min of continuous treatment and then rapidly declined. A similar effect was observed when the cells were exposed to a forskolin treatment, which resulted in nearly a twofold increase in phagocytic activity after a 10 min pulse. Both PMA and forskolin strongly stimulated phagocytosis (i.e. fivefold and threefold, respectively) in cells in which such activity had been completely inhibited by pre-exposure to the beta-receptor antagonist 1-propranolol.

  17. Phorbol 12-myristate 13-acetate prevents isoproterenol-induced morphological change in cultured vascular smooth muscle cells

    SciTech Connect

    Nabika, Toru; Chaldakov, G.N.; Nara, Yasuo; Endo, Jiro; Yamori, Yukio )

    1988-10-01

    The effect of phorbol 12-myristate 13-acetate (PMA) on isoproterenol (ISO)- and dibutyryl cAMP (dBcAMP)-induced morphological change and cytoskeletal reorganization was studied in cultured vascular smooth muscle cells (VSMC) using the fluorescence staining of actin and microtubules. The treatment of VSMC with 1.0 {mu}M of ISO or with 1.0 mM of dBcAMP for 90 min induced the disruption of actin-containing stress fibers followed by cytoplasmic arborization. The addition of 100 nM of PMA prevented both the destruction of actin fibers and cell arborization induced either by ISO or by dBcAMP. These results indicated that the inhibition of arborization by PMA was mediated through the activation of protein kinase C. Colchicine at 5.0 {mu}M also had an inhibitory effect on ISO- and dBcAMP-induced cell arborization. However, immunofluorescence studies revealed that colchicine but not PMA elicited the reorganization of microtubules, suggesting that the effect of PMA was mediated through a mechanism different from that of colchicine. The observations indicated that the morphology of VSMC was regulated through the alteration of cytoskeletal organization induced by cAMP-mediated and by protein kinase C-dependent systems.

  18. Characterization of Heterologously Expressed Acetyl Xylan Esterase1 Isolated from the Anaerobic Rumen Fungus Neocallimastix frontalis PMA02

    PubMed Central

    Kwon, Mi; Song, Jaeyong; Park, Hong-Seog; Park, Hyunjin; Chang, Jongsoo

    2016-01-01

    Acetyl xylan esterase (AXE), which hydrolyzes the ester linkages of the naturally acetylated xylan and thus known to have an important role for hemicellulose degradation, was isolated from the anaerobic rumen fungus Neocallimastix frontatlis PMA02, heterologously expressed in Escherichi coli (E.coli) and characterized. The full-length cDNA encoding NfAXE1 was 1,494 bp, of which 978 bp constituted an open reading frame. The estimated molecular weight of NfAXE1 was 36.5 kDa with 326 amino acid residues, and the calculated isoelectric point was 4.54. The secondary protein structure was predicted to consist of nine α-helixes and 12 β-strands. The enzyme expressed in E.coli had the highest activity at 40°C and pH 8. The purified recombinant NfAXE1 had a specific activity of 100.1 U/mg when p-nitrophenyl acetate (p-NA) was used as a substrate at 40°C, optimum temperature. The amount of liberated acetic acids were the highest and the lowest when p-NA and acetylated birchwood xylan were used as substrates, respectively. The amount of xylose released from acetylated birchwod xylan was increased by 1.4 fold when NfAXE1 was mixed with xylanase in a reaction cocktail, implying a synergistic effect of NfAXE1 with xylanase on hemicellulose degradation. PMID:27383808

  19. Influence of hyaluronic acid or phorbol 12-myristate 13-acetate on the migration capacity of a murine lymphoma cell line (Eb) and its metastatic variant (ESb).

    PubMed

    Kubens, B S; Nikolai, G; Zänker, K S

    1997-10-14

    The in vitro migration of two murine T cell lymphoma cell lines (Eb and ESb) was studied employing a three-dimensional collagen matrix and time-lapse video recording. In the highly metastatic cell line ESb, which had a low spontaneous locomoting activity, migration could clearly be stimulated by hyaluronic acid (HA) whereas only a small increase was found after incubation with phorbol myristate acetate (PMA). The observed stimulation could be attributed to an increase in recruitment of locomoting cells and not to changes in migration parameters of motile individual cells such as percentage of time locomoting, velocity or distance migrated. Incubation of the low metastatic cell line Eb with HA led to a decrease in migration but blocking of CD44, the principle ligand for HA, by preincubation with an anti-CD44 mAb (KM114), followed by HA exposure increased the locomoting activity significantly. The effect was based on both an increase in recruitment as well as in all migration parameters regarding motile individual Eb cells.

  20. Expression of Acetate Permease-like (apl) Genes in Subsurface Communities of Geobacter Species Under Fluctuating Acetate Concentrations

    SciTech Connect

    Elifantz, H; N'Guessan, A L; Mouser, Paula; Williams, Kenneth H; Wilkins, Michael J; Risso, Carla; Holmes, Dawn; Long, Philip E; Lovley, Derek R

    2010-09-01

    The addition of acetate to uranium-contaminated aquifers in order to stimulate the growth and activity of Geobacter species that reduce uranium is a promising in situ bioremediation option. Optimizing this bioremediation strategy requires that sufficient acetate be added to promote Geobacter species growth. We hypothesized that under acetate-limiting conditions, subsurface Geobacter species would increase the expression of either putative acetate symporters genes (aplI and aplII). Acetate was added to a uranium-contaminated aquifer (Rifle, CO) in two continuous amendments separated by 5 days of groundwater flush to create changing acetate concentrations. While the expression of aplI in monitoring well D04 (high acetate) weakly correlated with the acetate concentration over time, the transcript levels for this gene were relatively constant in well D08 (low acetate). At the lowest acetate concentrations during the groundwater flush, the transcript levels of aplII were the highest. The expression of aplII decreased 2–10-fold upon acetate reintroduction. However, the overall instability of acetate concentrations throughout the experiment could not support a robust conclusion regarding the role of apl genes in response to acetate limitation under field conditions, in contrast to previous chemostat studies, suggesting that the function of a microbial community cannot be inferred based on lab experiments alone.

  1. Expression of acetate permease-like (apl) genes in subsurface communities of Geobacter species under fluctuating acetate concentrations

    SciTech Connect

    Elifantz, H.; N'Guessan, L.A.; Mouser, P.J.; Williams, K H.; Wilkins, M J.; Risso, C.; Holmes, D.E.; Long, P.E.; Lovley, D.R.

    2010-03-01

    The addition of acetate to uranium-contaminated aquifers in order to stimulate the growth and activity of Geobacter species that reduce uranium is a promising in situ bioremediation option. Optimizing this bioremediation strategy requires that sufficient acetate be added to promote Geobacter species growth. We hypothesized that under acetate-limiting conditions, subsurface Geobacter species would increase the expression of either putative acetate symporters genes (aplI and aplII). Acetate was added to a uranium-contaminated aquifer (Rifle, CO) in two continuous amendments separated by 5 days of groundwater flush to create changing acetate concentrations. While the expression of aplI in monitoring well D04 (high acetate) weakly correlated with the acetate concentration over time, the transcript levels for this gene were relatively constant in well D08 (low acetate). At the lowest acetate concentrations during the groundwater flush, the transcript levels of aplII were the highest. The expression of aplII decreased 2-10-fold upon acetate reintroduction. However, the overall instability of acetate concentrations throughout the experiment could not support a robust conclusion regarding the role of apl genes in response to acetate limitation under field conditions, in contrast to previous chemostat studies, suggesting that the function of a microbial community cannot be inferred based on lab experiments alone.

  2. Stimulation of arachidonic acid metabolism in primary cultures of osteoblast-like cells by hormones and drugs

    SciTech Connect

    Feyen, J.H.; van der Wilt, G.; Moonen, P.; Di Bon, A.; Nijweide, P.J.

    1984-12-01

    The effects of parathyroid hormone (PTH), dihydroxycholecalciferol (1,25-(OH)2 D3), thrombin, epidermal growth factor (EGF) and 12-o-tetradecanoylphorbol-13-acetate (PMA) on the biosynthesis and release of arachidonic acid metabolites were studied in primary cultures of osteoblast-like cells isolated from 18-day-old chick embryo calvaria. Cells were labelled with (/sup 14/C)-arachidonic acid for 30 h. The radioactive eicosanoids were extracted from the cell culture media after a further 30 h stimulation period and analysed on a PRP-1 column by HPLC. The radioactive products were characterized by co-elution of (/sup 3/H) standard prostanoids. Osteoblasts showed a basal release of the prostanoids 6-keto-PGF1 alpha, TXB2, PGF2 alpha, PGE2, PGD2 and PGB2, the latter being the most abundant one. Indomethacin (10(-5) M) effectively inhibited the basal release, but not that of an as yet unidentified compound. The release of prostanoids was stimulated by PTH (2 U/ml), thrombin (0.4 NIH/ml), EGF (50 ng/ml) and PMA (25 ng/ml), the latter being by far the most potent one. 1,25-(OH)2D3 was found to slightly inhibit the prostanoid release. These results indicate: (1) primary cultures of osteoblasts synthesize several prostaglandins, thromboxane B2 and one unidentified product. (2) the action on bone of PTH and the various drugs tested may be, at least partly, mediated by an increased prostaglandin production by osteoblasts. Clearly this does not apply to 1,25-(OH)2D3.

  3. The PMA-1 is unwrapped in the SSPF prior to its attachment to Node 1

    NASA Technical Reports Server (NTRS)

    1997-01-01

    International Space Station (ISS) contractors unwrap Pressurized Mating Adapter-1 (PMA-1) for the ISS in KSC's Space Station Processing Facility. A PMA is a cone-shaped connector that will be attached to Node 1, the space station's structural building block, during ground processing. Node 1 with two PMAs attached will be the first element of the station scheduled to be launched aboard the Space Shuttle Endeavour on STS-88 in July 1998.

  4. Phorbol myristate acetate and catechol as skin cocarcinogens in SENCAR mice

    SciTech Connect

    Van Duuren, B.L.; Melchionne, S.; Seidman, I.

    1986-09-01

    The enhancement of the carcinogenicity of benzo(a) pyrene (B(a)P) and ..beta..-propiolactone (BPL) by the mouse skin cocarcinogens phorbol myristate acetate (PMA) and catechol were examined in female SENCAR mice, 30 per group. The carcinogen and cocarcinogen were applied simultaneously, three times weekly for 490-560 days. B(a)P and BPL were used at constant doses of 5 and 50 ..mu..g, respectively, in all experiments. PMA was used at three doses, 2.5, 1.0, and 0.5 ..mu..g per application, and catechol was used at one dose, 2 mg per application. Control groups included animals that received carcinogen only, cocarcinogen only, acetone only, and no treatment. The carcinogenicity of B(a)P and BPL were enhanced by the cocarcinogens, particularly in terms of tumor multiplicity. For both carcinogens, the most marked cocarcinogenic effects were observed at the lowest dose of PMA used (0.5 ..mu..g per application). This observation applied for days to first tumor, animals with tumors, tumor multiplicity, and incidence of malignant skin tumors. Catechol applied alone did not induce any tumors; with PMA alone there were significant incidences of benign and malignant tumors, e.g., at a dose of only 0.5 ..mu..g per application, 15 of 30 animals had 28 tumors, 5 of which were squamous carcinomas. In two-stage carcinogenesis experiments with 7,12-dimethylbenz(a)anthracene (DMBA) as initiator and PMA as promoter, SENCAR mice showed a greater susceptibility to tumor induction when compared to ICR/Ha mice used in earlier work. This susceptibility was most notable in terms of rate of tumor appearance and tumor multiplicity.

  5. Increased intestinal protein permeability in a model of lung injury induced by phorbol myristate acetate.

    PubMed

    St John, R C; Mizer, L A; Weisbrode, S E; Dorinsky, P M

    1991-11-01

    Multiple nonpulmonary organ failure is a frequent complication of the adult respiratory distress syndrome (ARDS), and contributes significantly to the high mortality rate associated with this disorder. Although previous studies suggest that systemic organ injury may be an integral component of ARDS, little is known about the specific functional alterations that occur in these target organs. The present study was designed, therefore, to test the hypothesis that endothelial damage, as assessed by microvascular permeability changes, develops in systemic organs in a model of acute lung injury. To test this postulate, the microvascular permeability for total protein was estimated using the steady-state relationship between the lymph (CL) to plasma (Cp) protein concentration ratio (i.e., CL/Cp) and lymph flow in autoperfused cat ileum preparations. Specifically, CL/Cp was measured in five cats, 2 h after acute lung injury was induced by intravenously administered phorbol myristate acetate (PMA), 15 micrograms/kg, and the results were compared with those of seven time-matched control animals. Prior to PMA infusion, the PaO2/FIO2 ratio was 451 +/- 28 in both groups and remained unchanged (486 +/- 26) in the control group. By contrast, the PaO2/FIO2 ratio fell to 275 +/- 95 after PMA infusion (p less than 0.05). In addition, whereas CL/Cp was 0.099 +/- 0.008 in the control animals, it increased to 0.36 +/- 0.06 in the PMA-injured animals (p less than 0.01). In summary, this study demonstrated that in this model of acute lung injury produced by PMA-induced activation of circulating inflammatory cells, both acute lung injury and systemic organ injury (i.e., morphologic and permeability alterations) occurred.

  6. Prostaglandin F2alpha stimulates the Raf/MEK1/mitogen-activated protein kinase signaling cascade in bovine luteal cells.

    PubMed

    Chen, D B; Westfall, S D; Fong, H W; Roberson, M S; Davis, J S

    1998-09-01

    Upon binding to its G protein-coupled transmembrane receptors, the actions of PGF2alpha on the corpus luteum are initiated by the phospholipase C/diacylglycerol-inositol 1,4,5-trisphosphate (InsP3)/Ca2+-protein kinase C (PKC) pathway. However, little is known about the downstream intracellular signaling events that can lead to transcriptional activation in response to PGF2alpha. The present study was conducted to examine the involvement of the mitogen-activated protein kinase (MAPK) signaling cascade in the corpus luteum. Three isoforms of the Raf family of oncoprotein kinases (A-Raf, B-Raf, and Raf-1 or c-Raf) were detected in bovine luteal cells. Raf-1 and B-Raf, but not A-Raf, were activated by PGF2alpha (1 microM) and the pharmacological PKC activator phorbol myristate acetate (PMA, 20 nM). Kinetic analysis revealed that PGF2alpha rapidly and transiently activated Raf-1. In vitro protein kinase assays demonstrated that activation of Raf-1 and B-Raf resulted in the phosphorylation and activation of MAPK kinase (MEK1), which subsequently phosphorylated p42mapk. As determined by hyperphosphorylation, tyrosine phosphorylation, and enzymatic activity, p42mapk and p44mapk were rapidly and transiently activated by both PGF2alpha (1 microM) and PMA (20 nM). Additionally, both PGF2alpha (1 microM) and PMA (20 nM) stimulated phosphorylation of Raf-1, MEK1, and p42mapk in 32P-labeled cells. Our data demonstrate that PGF2alpha activates the Raf/MEK1/p42/44mapk signaling cascade in bovine luteal cells and that the actions of PGF2alpha are mimicked by the PKC activator PMA. Activation of the Raf/MEK1/MAPK signaling cascade by PGF2alpha in luteal cells provides a mechanism to transduce signals initiated by PGF2alpha receptors on the cell surface into the nucleus. Activation of the Raf/MEK1/MAPK signaling cascade may be associated with transcriptional activation of luteal genes possessing activator protein-1-binding sites.

  7. [6]-Gingerol induces caspase-dependent apoptosis and prevents PMA-induced proliferation in colon cancer cells by inhibiting MAPK/AP-1 signaling.

    PubMed

    Radhakrishnan, E K; Bava, Smitha V; Narayanan, Sai Shyam; Nath, Lekshmi R; Thulasidasan, Arun Kumar T; Soniya, Eppurathu Vasudevan; Anto, Ruby John

    2014-01-01

    We report mechanism-based evidence for the anticancer and chemopreventive efficacy of [6]-gingerol, the major active principle of the medicinal plant, Ginger (Zingiber officinale), in colon cancer cells. The compound was evaluated in two human colon cancer cell lines for its cytotoxic effect and the most sensitive cell line, SW-480, was selected for the mechanistic evaluation of its anticancer and chemopreventive efficacy. The non-toxic nature of [6]-gingerol was confirmed by viability assays on rapidly dividing normal mouse colon cells. [6]-gingerol inhibited cell proliferation and induced apoptosis as evidenced by externalization of phosphatidyl serine in SW-480, while the normal colon cells were unaffected. Sensitivity to [6]-gingerol in SW-480 cells was associated with activation of caspases 8, 9, 3 &7 and cleavage of PARP, which attests induction of apoptotic cell death. Mechanistically, [6]-gingerol down-regulated Phorbol Myristate Acetate (PMA) induced phosphorylation of ERK1/2 and JNK MAP kinases and activation of AP-1 transcription factor, but had only little effects on phosphorylation of p38 MAP kinase and activation of NF-kappa B. Additionally, it complemented the inhibitors of either ERK1/2 or JNK MAP kinase in bringing down the PMA-induced cell proliferation in SW-480 cells. We report the inhibition of ERK1/2/JNK/AP-1 pathway as a possible mechanism behind the anticancer as well as chemopreventive efficacy of [6]-gingerol against colon cancer.

  8. Preparation of vinyl acetate

    DOEpatents

    Tustin, Gerald Charles; Zoeller, Joseph Robert; Depew, Leslie Sharon

    1998-01-01

    This invention pertains to the preparation of vinyl acetate by contacting a mixture of hydrogen and ketene with a heterogeneous catalyst containing a transition metal to produce acetaldehyde, which is then reacted with ketene in the presence of an acid catalyst to produce vinyl acetate.

  9. Preparation of vinyl acetate

    DOEpatents

    Tustin, G.C.; Zoeller, J.R.; Depew, L.S.

    1998-03-24

    This invention pertains to the preparation of vinyl acetate by contacting a mixture of hydrogen and ketene with a heterogeneous catalyst containing a transition metal to produce acetaldehyde, which is then reacted with ketene in the presence of an acid catalyst to produce vinyl acetate.

  10. The role of protein kinase C in transmembrane signaling by the T cell antigen receptor complex. Effects of stimulation with soluble or immobilized CD3 antibodies.

    PubMed

    Manger, B; Weiss, A; Imboden, J; Laing, T; Stobo, J D

    1987-10-15

    Phorbol esters, such as phorbol myristate acetate (PMA), are known to be potent co-stimulants with calcium ionophores for activation of T lymphocytes. The most extensively studied intracellular effect of PMA is its ability to activate the cytoplasmic enzyme protein kinase C (pkC). Herein, we examined the role of pkC activation during T cell activation. During physiologic activation, this enzyme is activated by diacylglycerol which is generated through the hydrolysis of polyphosphoinositides. Therefore, we studied the activation of T lymphocytes induced by a synthetic diacylglycerol, dioctanoylglycerol. In contrast to PMA, this compound can be metabolized in T cells and presumably more closely mimics physiologic activation of pkC. Dioctanoylglycerol together with reagents that induce increases in intracellular free Ca2+ concentration, Ca2+ ionophores, or anti-cluster designation (CD)3 monoclonal antibodies (mAb) were able to induce interleukin 2 receptor expression and proliferation of T lymphocytes. Previous studies have demonstrated that the stimulation of T cells via the CD3/T cell antigen receptor complex by mAb against CD3 leads to an increase in cytoplasmic free Ca2+ and to an activation of pkC. Paradoxically, however, soluble CD3 antibodies do not cause proliferation of resting purified T cells. Inasmuch as immobilization of CD3 mAb has been shown to influence the agonist properties of such antibodies, we compared the ability of soluble and immobilized CD3 mAb to activate pkC. We demonstrated herein that soluble CD3 mAb cause only a very transient activation of pkC in the T cell leukemic line Jurkat. This pkC activation is markedly prolonged when Jurkat cells are stimulated with immobilized rather than soluble CD3 antibodies. These studies suggest that activation of pkC plays a major role in T cell activation and that the activation of pkC is influenced by the form in which CD3 mAb is presented to T cells.

  11. Quantifying transient psychological stress using a novel technique: changes to PMA-induced leukocyte production of ROS in vitro.

    PubMed

    Shelton-Rayner, Graham K; Mian, Rubina; Chandler, Simon; Robertson, Duncan; Macdonald, David W

    2011-01-01

    Although much work has been conducted to quantify the long-term physiological effects of psychological stress, measures of short-term, low-level stress have been more elusive. This study assessed the effect of exposure of volunteers to a mild, brief, psychologically stressful event, on the functional ability of leukocytes in whole blood to respond to phorbol 12-myristate 13-acetate (PMA) in vitro. Volunteers operated a car electric window and adjusted it to 4 pre-determined positions. Between each operation the mechanism's polarity was covertly altered (group B) or remained unaltered (group A). For each treatment group 10 different subjects provided capillary blood samples pre- and post-stressor. Using a chemiluminescent technique termed leukocyte coping capacity, the ability of leukocytes to produce reactive oxygen species (ROS) in vitro was assessed. ROS release differed significantly at 10 min post-stressor between treatment groups, suggesting exposure to acute psychological stress leads to a reduced ability to respond to bacterial challenge.

  12. Cytosolic retention of phosphorylated extracellular signal-regulated kinase and a Rho-associated kinase-mediated signal impair expression of p21(Cip1/Waf1) in phorbol 12-myristate-13- acetate-induced apoptotic cells.

    PubMed

    Lai, Jin-Mei; Wu, Sulin; Huang, Duen-Yi; Chang, Zee-Fen

    2002-11-01

    In response to treatment with phorbol-12-myristate-13-acetate (PMA), the half-population of erythromyeloblast D2 cells, a cytokine-independent variant of TF-1 cells, displayed adhesion and differentiated into a monocyte/macrophage-like morphology, while the other half-population remained in suspension and underwent apoptosis. Expression of the cell cycle inhibitor p21(Cip1/Waf1) was induced after PMA treatment in the adherent cells but not in the proapoptotic cells. We investigated the mechanism responsible for the impairment of p21(Cip1/Waf1) induction in PMA-induced proapoptotic cells. We demonstrated that in PMA-induced adherent cells, upregulation of p21(Cip1/Waf1) requires the activation and nuclear translocation of phosphorylated extracellular signal-regulated kinase (phospho-ERK). Although ERK was phosphorylated to comparable levels in PMA-induced proapoptotic and adherent cells, nuclear distribution of phospho-ERK was seen only in the adherent, not in the proapoptotic cells. We also found that only PMA-induced proapoptotic cells contained the phosphorylated form of myosin light chain, which is dependent on Rho-associated kinase (ROCK) activation, and that expression of a dominant-active form of ROCK suppressed activation of the p21(Cip1/Waf1) promoter during PMA induction. Finally, we demonstrated that inhibition of ROCK restores nuclear distribution of phospho-ERK and activation of p21(Cip1/Waf1) expression. Based on these findings, we propose that a ROCK-mediated signal is involved in interfering with the process of ERK-mediated p21(Cip1/Waf1) induction in PMA-induced proapoptotic TF-1 and D2 cells.

  13. Analysis of the mechanisms involved in the stimulation of neutrophil apoptosis by tumour necrosis factor-α

    PubMed Central

    Salamone, Gabriela; Trevani, Analía; Martínez, Diego; Vermeulen, Mónica; Gamberale, Romina; Fernández-Calotti, Paula; Raiden, Silvina; Giordano, Mirta; Geffner, Jorge

    2004-01-01

    We have previously reported that human neutrophils pretreated with tumour necrosis factor-α (TNF-α) and then exposed to a variety of agents such as immune complexes, zymosan, phorbol 12-myristate 13-acetate (PMA), C5a, fMLP, or granulocyte–macrophage colony-stimulating factor (GM-CSF), undergo a dramatic stimulation of apoptosis, suggesting that TNF-α is able to prime an apoptotic death programme which can be rapidly triggered by different stimuli. We report here that this response involves the participation of Mac-1 (CD11b/CD18), is dependent on caspases 3, 8 and 9, and is associated with both a loss of mitochondrial transmembrane potential and a down-regulation in expression of the anti-apoptotic protein, Mcl-1. Interestingly, we also found that the anti-apoptotic cytokine interleukin-1 (IL-1) improves the ability of TNF-α to promote apoptosis, supporting the notion than TNF-α, acting together with IL-1, may favour the depletion of neutrophils from the inflammatory areas during the course of acute inflammation. PMID:15500622

  14. PMA and crystal-induced neutrophil extracellular trap formation involves RIPK1-RIPK3-MLKL signaling.

    PubMed

    Desai, Jyaysi; Kumar, Santhosh V; Mulay, Shrikant R; Konrad, Lukas; Romoli, Simone; Schauer, Christine; Herrmann, Martin; Bilyy, Rostyslav; Müller, Susanna; Popper, Bastian; Nakazawa, Daigo; Weidenbusch, Marc; Thomasova, Dana; Krautwald, Stefan; Linkermann, Andreas; Anders, Hans-Joachim

    2016-01-01

    Neutrophil extracellular trap (NET) formation contributes to gout, autoimmune vasculitis, thrombosis, and atherosclerosis. The outside-in signaling pathway triggering NET formation is unknown. Here, we show that the receptor-interacting protein kinase (RIPK)-1-stabilizers necrostatin-1 or necrostatin-1s and the mixed lineage kinase domain-like (MLKL)-inhibitor necrosulfonamide prevent monosodium urate (MSU) crystal- or PMA-induced NET formation in human and mouse neutrophils. These compounds do not affect PMA- or urate crystal-induced production of ROS. Moreover, neutrophils of chronic granulomatous disease patients are shown to lack PMA-induced MLKL phosphorylation. Genetic deficiency of RIPK3 in mice prevents MSU crystal-induced NET formation in vitro and in vivo. Thus, neutrophil death and NET formation may involve the signaling pathway defining necroptosis downstream of ROS production. These data imply that RIPK1, RIPK3, and MLKL could represent molecular targets in gout or other crystallopathies. PMID:26531064

  15. Optimization of PMA-PCR Protocol for Viability Detection of Pathogens

    NASA Technical Reports Server (NTRS)

    Mikkelson, Brian J.; Lee, Christine M.; Ponce, Adrian

    2011-01-01

    This presented study demonstrates the need that PMA-PCR can be used to capture the loss of viability of a sample that is much more specific and time-efficient than alternative methods. This protocol is particularly useful in scenarios in which sterilization treatments may inactivate organisms but not degrade their DNA. The use of a PCR-based method of pathogen detection without first inactivating the DNA of nonviable cells will potentially lead to false positives. The loss of culturability, by heat-killing, did not prevent amplified PCR products, which supports the use of PMA to prevent amplification and differentiate between viable and dead cells. PMA was shown to inhibit the amplification of DNA by PCR in vegetative cells that had been heat-killed.

  16. 21 CFR 814.9 - Confidentiality of data and information in a premarket approval application (PMA) file.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Confidentiality of data and information in a... General § 814.9 Confidentiality of data and information in a premarket approval application (PMA) file. (a) A “PMA file” includes all data and information submitted with or incorporated by reference in...

  17. Cu/Zn superoxide dismutase and the proton ATPase Pma1p of Saccharomyces cerevisiae

    SciTech Connect

    Baron, J. Allen; Chen, Janice S.; Culotta, Valeria C.

    2015-07-03

    In eukaryotes, the Cu/Zn containing superoxide dismutase (SOD1) plays a critical role in oxidative stress protection as well as in signaling. We recently demonstrated a function for Saccharomyces cerevisiae Sod1p in signaling through CK1γ casein kinases and identified the essential proton ATPase Pma1p as one likely target. The connection between Sod1p and Pma1p was explored further by testing the impact of sod1Δ mutations on cells expressing mutant alleles of Pma1p that alter activity and/or post-translational regulation of this ATPase. We report here that sod1Δ mutations are lethal when combined with the T912D allele of Pma1p in the C-terminal regulatory domain. This “synthetic lethality” was reversed by intragenic suppressor mutations in Pma1p, including an A906G substitution that lies within the C-terminal regulatory domain and hyper-activates Pma1p. Surprisingly the effect of sod1Δ mutations on Pma1-T912D is not mediated through the Sod1p signaling pathway involving the CK1γ casein kinases. Rather, Sod1p sustains life of cells expressing Pma1-T912D through oxidative stress protection. The synthetic lethality of sod1Δ Pma1-T912D cells is suppressed by growing cells under low oxygen conditions or by treatments with manganese-based antioxidants. We now propose a model in which Sod1p maximizes Pma1p activity in two ways: one involving signaling through CK1γ casein kinases and an independent role for Sod1p in oxidative stress protection. - Highlights: • In yeast, the anti-oxidant enzyme SOD1 promotes activity of the proton ATPase Pma1p. • Cells expressing a T912D variant of Pma1p are not viable without SOD1. • SOD1 is needed to protect Pma1-T912D expressing cells from severe oxidative damage. • SOD1 activates Pma1p through casein kinase signaling and oxidative stress protection.

  18. Multianalyte Microphysiometry of Macrophage Responses to Phorbol Myristate Acetate, Lipopolysaccharide, and Lipoarabinomannan

    PubMed Central

    Kimmel, Danielle W.; Meschievitz, Mika E.; Hiatt, Leslie A.; Cliffel, David E.

    2015-01-01

    This study examined the hypothesis that mycobacterial antigens generate different metabolic responses in macrophages as compared to gram-negative effectors and macrophage activators. The metabolic activation of macrophages by PMA is a useful tool for studying virulent agents and can be compared to other effectors. While phorbol myristate acetate (PMA) is commonly used to study macrophage activation, the concentration used to create this physiological response varies. The response of RAW-264.7 macrophages is concentration-dependent, where the metabolic response to high concentrations of PMA decreases suggesting deactivation. The gram-negative effector, lipopolysaccharide (LPS), was seen to promote glucose and oxygen production which were used to produce a delayed onset of oxidative burst. Pre-incubation with interferon-γ (IFN-γ) increased the effect on cell metabolism, where the synergistic effects of IFN-γ and LPS immediately initiated oxidative burst. These studies exhibited a stark contrast with lipoarabinomannan (LAM), an antigenic glycolipid component associated with the bacterial genus Mycobacterium. The presence of LAM effectively inhibits any metabolic response preventing consumption of glucose and oxygen for the promotion of oxidative burst and to ensure pathogenic proliferation. This study demonstrates for the first time the immediate inhibitory metabolic effects LAM has on macrophages, suggesting implications for future intervention studies with Mycobacterium tuberculosis. PMID:25798034

  19. Self-assemblies of γ-CDs with pentablock copolymers PMA-PPO-PEO-PPO-PMA and endcapping via atom transfer radical polymerization of 2-methacryloyloxyethyl phosphorylcholine

    PubMed Central

    Lin, Jing; Kong, Tao; Ye, Lin; Zhang, Ai-ying

    2015-01-01

    Summary Pentablock copolymers PMA-PPO-PEO-PPO-PMA synthesized via atom transfer radical polymerization (ATRP) were self-assembled with varying amounts of γ-CDs to prepare poly(pseudorotaxanes) (PPRs). When the concentration of γ-CDs was lower, the central PEO segment served as a shell of the micelles and was preferentially bent to pass through the γ-CD cavity to construct double-chain-stranded tight-fit PPRs characterized by a channel-like crystal structure. With an increase in the amount of γ-CDs added, they began to accommodate the poly(methyl acrylate) (PMA) segments dissociated from the core of the micelles. When more γ-CDs were threaded and slipped over the segments, the γ-CDs were randomly distributed along the pentablock copolymer chain to generate single-chain-stranded loose-fit PPRs and showed no characteristic channel-like crystal structure. All the self-assembly processes of the pentablock copolymers resulted in the formation of hydrogels. After endcapping via in situ ATRP of 2-methacryloyloxyethyl phosphorylcholine (MPC), these single-chain-stranded loose-fit PPRs were transformed into conformational identical polyrotaxanes (PRs). The structures of the PPRs and PRs were characterized by means of 1H NMR, GPC, 13C CP/MAS NMR, 2D 1H NOESY NMR, FTIR, WXRD, TGA and DSC analyses. PMID:26732122

  20. Methane from acetate.

    PubMed

    Ferry, J G

    1992-09-01

    The general features are known for the pathway by which most methane is produced in nature. All acetate-utilizing methanogenic microorganisms contain CODH which catalyzes the cleavage of acetyl-CoA; however, the pathway differs from all other acetate-utilizing anaerobes in that the methyl group is reduced to methane with electrons derived from oxidation of the carbonyl group of acetyl-CoA to CO2. The current understanding of the methanogenic fermentation of acetate provides impressions of nature's novel solutions to problems of methyl transfer, electron transport, and energy conservation. The pathway is now at a level of understanding that will permit productive investigations of these and other interesting questions in the near future. PMID:1512186

  1. 21 CFR 814.46 - Withdrawal of approval of a PMA.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.46 Withdrawal of approval... that the device is safe for use under the conditions prescribed, recommended, or suggested in its... safety and effectiveness of the device, including information about any adverse effects of the device...

  2. 21 CFR 814.46 - Withdrawal of approval of a PMA.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES FDA Action on a PMA § 814.46 Withdrawal of approval... that the device is safe for use under the conditions prescribed, recommended, or suggested in its... safety and effectiveness of the device, including information about any adverse effects of the device...

  3. 21 CFR 814.47 - Temporary suspension of approval of a PMA.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Temporary suspension of approval of a PMA. 814.47 Section 814.47 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES..., or modify any part 16 procedure pursuant to § 10.19 of this chapter. (3) FDA shall deem the...

  4. 21 CFR 814.47 - Temporary suspension of approval of a PMA.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Temporary suspension of approval of a PMA. 814.47 Section 814.47 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES..., or modify any part 16 procedure pursuant to § 10.19 of this chapter. (3) FDA shall deem the...

  5. 21 CFR 814.44 - Procedures for review of a PMA.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... provide additional information to the panel. FDA will maintain a record of all communications with the... will issue to the applicant an order approving a PMA if none of the reasons in § 814.45 for denying... labeling before marketing. FDA will also give the public notice of the order, including notice of...

  6. Metabolism of 4-chloro-2-nitrophenol in a Gram-positive bacterium, Exiguobacterium sp. PMA

    PubMed Central

    2012-01-01

    Background Chloronitrophenols (CNPs) are widely used in the synthesis of dyes, drugs and pesticides, and constitute a major group of environmental pollutants. 4-Chloro-2-nitrophenol (4C2NP) is an isomer of CNPs that has been detected in various industrial effluents. A number of physicochemical methods have been used for treatment of wastewater containing 4C2NP. These methods are not as effective as microbial degradation, however. Results A 4C2NP-degrading bacterium, Exiguobacterium sp. PMA, which uses 4C2NP as the sole carbon and energy source was isolated from a chemically-contaminated site in India. Exiguobacterium sp. PMA degraded 4C2NP with the release of stoichiometeric amounts of chloride and ammonium ions. The effects of different substrate concentrations and various inoculum sizes on degradation of 4C2NP were investigated. Exiguobacterium sp. PMA degraded 4C2NP up to a concentration of 0.6 mM. High performance liquid chromatography and gas chromatography–mass spectrometry identified 4-chloro-2-aminophenol (4C2AP) and 2-aminophenol (2AP) as possible metabolites of the 4C2NP degradation pathway. The crude extract of 4C2NP-induced PMA cells contained enzymatic activity for 4C2NP reductase and 4C2AP dehalogenase, suggesting the involvement of these enzymes in the degradation of 4C2NP. Microcosm studies using sterile and non-sterile soils spiked with 4C2NP were carried out to monitor the bioremediation potential of Exiguobacterium sp. PMA. The bioremediation of 4C2NP by Exiguobacterium sp. PMA was faster in non-sterilized soil than sterilized soil. Conclusions Our studies indicate that Exiguobacterium sp. PMA may be useful for the bioremediation of 4C2NP-contaminated sites. This is the first report of (i) the formation of 2AP in the 4C2NP degradation pathway by any bacterium and (iii) the bioremediation of 4C2NP by any bacterium. PMID:23171039

  7. Evaluation of quantitative PCR combined with PMA treatment for molecular assessment of microbial water quality.

    PubMed

    Gensberger, Eva Theres; Polt, Marlies; Konrad-Köszler, Marianne; Kinner, Paul; Sessitsch, Angela; Kostić, Tanja

    2014-12-15

    Microbial water quality assessment currently relies on cultivation-based methods. Nucleic acid-based techniques such as quantitative PCR (qPCR) enable more rapid and specific detection of target organisms and propidium monoazide (PMA) treatment facilitates the exclusion of false positive results caused by DNA from dead cells. Established molecular assays (qPCR and PMA-qPCR) for legally defined microbial quality parameters (Escherichia coli, Enterococcus spp. and Pseudomonas aeruginosa) and indicator organism group of coliforms (implemented on the molecular detection of Enterobacteriaceae) were comparatively evaluated to conventional microbiological methods. The evaluation of an extended set of drinking and process water samples showed that PMA-qPCR for E. coli, Enterococcus spp. and P. aeruginosa resulted in higher specificity because substantial or complete reduction of false positive signals in comparison to qPCR were obtained. Complete compliance to reference method was achieved for E. coli PMA-qPCR and 100% specificity for Enterococcus spp. and P. aeruginosa in the evaluation of process water samples. A major challenge remained in sensitivity of the assays, exhibited through false negative results (7-23%), which is presumably due to insufficient sample preparation (i.e. concentration of bacteria and DNA extraction), rather than the qPCR limit of detection. For the detection of the indicator group of coliforms, the evaluation study revealed that the utilization of alternative molecular assays based on the taxonomic group of Enterobacteriaceae was not adequate. Given the careful optimization of the sensitivity, the highly specific PMA-qPCR could be a valuable tool for rapid detection of hygienic parameters such as E. coli, Enterococcus spp. and P. aeruginosa.

  8. Phosphorylation of CD18 in response to neutrophil stimulation

    SciTech Connect

    Jakes, S.; Schembri-King, J.; Wallace, R.W. )

    1991-03-11

    Leukocyte integrins containing the common {beta}-subunit (CD18) mediate the adhesion of leukocytes to endothelial cells. It has been shown that the CD18 is phosphorylated in response to the phorbol ester PMA and proposed that phosphorylation of CD18 triggers the enhanced avidity of leukocyte integrins. The purpose of this study was to determine if CD18 in human neutrophils is also phosphorylated in response to physiological stimuli, i.e. receptor mediated activation. After labeling freshly isolated human neutrophils with {sup 32}p it was found that CD18 was phosphorylated in response to PMA in a time dependent manner that corresponded to the rate of PMA induced homotypic aggregation. The receptor mediated stimuli fMLP, LTB{sub 4}, IL-8, and C5a were also effective at initiating rapid CD18 dependent homotypic aggregation of neutrophils. However, in none of the receptor mediated responses was the level of CD18 phosphorylation increased at any time from the addition of stimuli to the peak of homotypic aggregation. Though not conclusive, this study suggests that in human neutrophils, activation of the leukocyte integrins by PMA may involve signaling pathways distinct from those involved in activation through receptor mediated stimulation.

  9. Acetate Production by Methanogenic Bacteria

    PubMed Central

    Westermann, Peter; Ahring, Birgitte K.; Mah, Robert A.

    1989-01-01

    Methanosarcina barkeri MS and 227 and Methanosarcina mazei S-6 produced acetate when grown on H2-CO2, methanol, or trimethylamine. Marked differences in acetate production by the two bacterial species were found, even though methane and cell yields were nearly the same. M. barkeri produced 30 to 75 μmol of acetate per mmol of CH4 formed, but M. mazei produced only 8 to 9 μmol of acetate per mmol of CH4. PMID:16348006

  10. Acetate dependence of tumors.

    PubMed

    Comerford, Sarah A; Huang, Zhiguang; Du, Xinlin; Wang, Yun; Cai, Ling; Witkiewicz, Agnes K; Walters, Holly; Tantawy, Mohammed N; Fu, Allie; Manning, H Charles; Horton, Jay D; Hammer, Robert E; McKnight, Steven L; Tu, Benjamin P

    2014-12-18

    Acetyl-CoA represents a central node of carbon metabolism that plays a key role in bioenergetics, cell proliferation, and the regulation of gene expression. Highly glycolytic or hypoxic tumors must produce sufficient quantities of this metabolite to support cell growth and survival under nutrient-limiting conditions. Here, we show that the nucleocytosolic acetyl-CoA synthetase enzyme, ACSS2, supplies a key source of acetyl-CoA for tumors by capturing acetate as a carbon source. Despite exhibiting no gross deficits in growth or development, adult mice lacking ACSS2 exhibit a significant reduction in tumor burden in two different models of hepatocellular carcinoma. ACSS2 is expressed in a large proportion of human tumors, and its activity is responsible for the majority of cellular acetate uptake into both lipids and histones. These observations may qualify ACSS2 as a targetable metabolic vulnerability of a wide spectrum of tumors.

  11. PMA-PhyloChip DNA Microarray to Elucidate Viable Microbial Community Structure

    NASA Technical Reports Server (NTRS)

    Venkateswaran, Kasthuri J.; Stam, Christina N.; Andersen, Gary L.; DeSantis, Todd

    2011-01-01

    Since the Viking missions in the mid-1970s, traditional culture-based methods have been used for microbial enumeration by various NASA programs. Viable microbes are of particular concern for spacecraft cleanliness, for forward contamination of extraterrestrial bodies (proliferation of microbes), and for crew health/safety (viable pathogenic microbes). However, a "true" estimation of viable microbial population and differentiation from their dead cells using the most sensitive molecular methods is a challenge, because of the stability of DNA from dead cells. The goal of this research is to evaluate a rapid and sensitive microbial detection concept that will selectively estimate viable microbes. Nucleic acid amplification approaches such as the polymerase chain reaction (PCR) have shown promise for reducing time to detection for a wide range of applications. The proposed method is based on the use of a fluorescent DNA intercalating agent, propidium monoazide (PMA), which can only penetrate the membrane of dead cells. The PMA-quenched reaction mixtures can be screened, where only the DNA from live cells will be available for subsequent PCR reaction and microarray detection, and be identified as part of the viable microbial community. An additional advantage of the proposed rapid method is that it will detect viable microbes and differentiate from dead cells in only a few hours, as opposed to less comprehensive culture-based assays, which take days to complete. This novel combination approach is called the PMA-Microarray method. DNA intercalating agents such as PMA have previously been used to selectively distinguish between viable and dead bacterial cells. Once in the cell, the dye intercalates with the DNA and, upon photolysis under visible light, produces stable DNA adducts. DNA cross-linked in this way is unavailable for PCR. Environmental samples suspected of containing a mixture of live and dead microbial cells/spores will be treated with PMA, and then incubated

  12. Effect of exposure to stress conditions on propidium monoazide (PMA)-qPCR based Campylobacter enumeration in broiler carcass rinses.

    PubMed

    Duarte, A; Botteldoorn, N; Coucke, W; Denayer, S; Dierick, K; Uyttendaele, M

    2015-06-01

    Campylobacter quantification by qPCR is unable to distinguish viable vs. dead cells in contrast to the culture-based ISO 10272-2 reference method. Propidium monoazide (PMA) has been used to overcome this disadvantage. A Campylobacter PMA-qPCR enumeration method was evaluated for its consistency and compared to the culture-based enumeration for both artificially and natural contaminated broiler carcass rinses. The PMA effect was further evaluated on stressed cells. Five conditions, commonly encountered during the slaughter process and storage (acid, heat, cold, oxidation and freezing), were inflicted to the broiler carcass rinses artificially contaminated with Campylobacter jejuni or Campylobacter coli. A better correlation between the reference method and the qPCR enumeration was obtained when PMA was used. The two cultured-based methods used showed a significant CFU reduction for heat, cold and acid stresses although the PMA-qPCR enumeration showed that viable bacteria were underestimated. Freezing showed the highest reduction effect, while the reduction extend was also overestimated by the microbiological enumeration procedure. Exposure to a mild oxidative stress was the only stress condition applied at temperatures permitting adaptation of Campylobacter and did not lead to either reduction in CFU nor in the PMA-qPCR signal.

  13. T-cell response to phorbol ester PMA and calcium ionophore A23187 in Down's syndrome.

    PubMed

    Bertotto, A; Crupi, S; Arcangeli, C; Gerli, R; Scalise, F; Fabietti, G; Agea, E; Vaccaro, R

    1989-11-01

    The proliferative response of purified T cells to anti-CD2 monoclonal antibodies (T112 plus T113) was found to be markedly reduced in 12 subjects with Down's syndrome (DS). The addition of phorbol ester PMA, which activates Ca2+/phospholipid-dependent enzyme protein kinase C, or calcium ionophore A23187, which increases intracytosolic free Ca2+ concentration, enhanced, but did not normalize, the defective anti-CD2-mediated T-cell mitogenesis. In contrast, the proliferation of resting lymphocytes from trisomic patients was comparable to that of the control cells when PMA and A23187 were used as co-blastogenic reagents. Because PMA and A23187 together bypass the early activation pathways and promote T-cell growth through the direct induction of membrane interleukin 2 (IL-2) receptor expression and IL-2 synthesis and secretion, it could reasonably be hypothesized that the faulty DS T-cell activation induced by antigen or mitogen is due to a deranged transmembrane signal transduction, rather than a defect in the later intracellular events. PMID:2573952

  14. PMA-Linked Fluorescence for Rapid Detection of Viable Bacterial Endospores

    NASA Technical Reports Server (NTRS)

    LaDuc, Myron T.; Venkateswaran, Kasthuri; Mohapatra, Bidyut

    2012-01-01

    The most common approach for assessing the abundance of viable bacterial endospores is the culture-based plating method. However, culture-based approaches are heavily biased and oftentimes incompatible with upstream sample processing strategies, which make viable cells/spores uncultivable. This shortcoming highlights the need for rapid molecular diagnostic tools to assess more accurately the abundance of viable spacecraft-associated microbiota, perhaps most importantly bacterial endospores. Propidium monoazide (PMA) has received a great deal of attention due to its ability to differentiate live, viable bacterial cells from dead ones. PMA gains access to the DNA of dead cells through compromised membranes. Once inside the cell, it intercalates and eventually covalently bonds with the double-helix structures upon photoactivation with visible light. The covalently bound DNA is significantly altered, and unavailable to downstream molecular-based manipulations and analyses. Microbiological samples can be treated with appropriate concentrations of PMA and exposed to visible light prior to undergoing total genomic DNA extraction, resulting in an extract comprised solely of DNA arising from viable cells. This ability to extract DNA selectively from living cells is extremely powerful, and bears great relevance to many microbiological arenas.

  15. Acetal phosphatidic acids: novel platelet aggregating agents.

    PubMed

    Brammer, J P; Maguire, M H; Walaszek, E J; Wiley, R A

    1983-05-01

    induce platelet aggregation per se by direct action at the platelet membrane, and that the acetal function is of primary importance in their potent platelet-stimulating activity. Moreover, as the acetal phosphatidic acids are the major components of the smooth muscle-contracting acidic phospholipid tissue extract ;Darmstoff' (Vogt, 1949), their potent platelet-aggregating properties may be of physiological or pathological significance.

  16. Treatment of mouse melanoma cells with phorbol 12-myristate 13-acetate counteracts mannosylerythritol lipid-induced growth arrest and apoptosis.

    PubMed

    Zhao, X; Geltinger, C; Kishikawa, S; Ohshima, K; Murata, T; Nomura, N; Nakahara, T; Yokoyama, K K

    2000-07-01

    Mannosylerythritol lipid (MEL), an extracellularglycolipid from yeast, induces the differentiation ofHL-60 promyelocytic leukemia cells towardsgranulocytes. We show here that MEL is also a potentinhibitor of the proliferation of mouse melanoma B16cells. Flow-cytometric analysis of the cell cycle ofMEL-treated B16 cells revealed the accumulation ofcells in the sub-G(0)/G(1) phase, which is a hallmark ofcells undergoing apoptosis. Treatment of B16 cellsfor 24 h with phorbol 12-myristate 13-acetate (PMA),an activator of protein kinase C (PKC), did notinterfere with the growth and survival of the cells,but it effectively counteracted the MEL-induced growtharrest and apoptosis. The activity of PKC was reducedin B16 cells treated with MEL at a concentration atwhich MEL induced apoptosis. However, incubation withPMA in addition to MEL reversed this reduction in theactivity of PKC. These results suggest thatconverging signaling pathways are triggeredindependently by MEL and PMA and that the signalsmight both be mediated by PKC. PMID:19002819

  17. Functionalisation of mesoporous silica gel with 2-[(phosphonomethyl)-amino]acetic acid functional groups. Characterisation and application

    NASA Astrophysics Data System (ADS)

    Caldarola, Dario; Mitev, Dimitar P.; Marlin, Lucile; Nesterenko, Ekaterina P.; Paull, Brett; Onida, Barbara; Bruzzoniti, Maria Concetta; Carlo, Rosa Maria De; Sarzanini, Corrado; Nesterenko, Pavel N.

    2014-01-01

    A new complexing adsorbent was prepared by chemical modification of mesoporous silica Kieselgel 60 (dp = 37-63 μm, average pore size 6 nm, specific surface area 425 m2 g-1) with 3-glycidoxypropyltrimethoxysilane and 2-[(phosphonomethyl)amino]acetic acid (PMA), commonly known as glyphosate. The prepared adsorbent was fully characterised using elemental analysis, thermal gravimetric analysis (TGA), acid-base potentiometric titration, Fourier Transform Infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), nitrogen adsorption isotherms at 77 K (BET), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS). The concentration of bonded PMA groups calculated from the nitrogen content was 0.38 mmol per gram. The adsorption of transition metal ions on PMA functionalised silica (HEPMAS) was studied from aqueous solutions having different pH and the following selectivity was established, Zn(II) < Co(II) < Cd(II) < Mn(II) < Ni(II) < Cu(II). The calculated values of distribution coefficients D for the adsorption of ecotoxic metal ions on HEPMAS are 5.0 × 104, 4.9 × 105 and 2.6 × 104 for Zn(II), Pb(II) and Cd(II), respectively.

  18. Quantifying fungal viability in air and water samples using quantitative PCR after treatment with propidium monoazide (PMA).

    PubMed

    Vesper, Stephen; McKinstry, Craig; Hartmann, Chris; Neace, Michelle; Yoder, Stephanie; Vesper, Alex

    2008-02-01

    A method is described to discriminate between live and dead cells of the infectious fungi Aspergillus fumigatus, Aspergillus flavus, Aspergillus terreus, Mucor racemosus, Rhizopus stolonifer and Paecilomyces variotii. To test the method, conidial suspensions were heat inactivated at 85 degrees C or held at 5 degrees C (controls) for 1 h. Polycarbonate filters (25 mm diameter, 0.8 microm pore size) were placed on "welled" slides (14 mm diameter) and the filters treated with either PBS or PMA. Propidium monoazide (PMA), which enters dead cells but not live cells, was incubated with cell suspensions, exposed to blue wavelength light-emitting diodes (LED) to inactivate remaining PMA and secure intercalation of PMA with DNA of dead cells. Treated cells were extracted and the live and dead cells evaluated with quantitative PCR (QPCR). After heat treatment and DNA modification with PMA, all fungal species tested showed an approximate 100- to 1000-fold difference in cell viability estimated by QPCR analysis which was consistent with estimates of viability based on culturing.

  19. Influence of genetic polymorphism on t,t-MA/S-PMA ratio in 301 benzene exposed subjects.

    PubMed

    Carbonari, Damiano; Proietto, Annarita; Fioretti, Marzia; Tranfo, Giovanna; Paci, Enrico; Papacchini, Maddalena; Mansi, Antonella

    2014-12-01

    This study investigated the effect of polymorphic genes GSTT1, GSTM1, GSTA1, EHPX1, NQO1, CYP2E1, CYP1A and MPO on the urinary concentrations and ratio (R) of the benzene metabolites trans,trans-muconic acid (t,t-MA) and S-phenyl mercapturic acid (S-PMA) in 301 oil refinery workers. The metabolites' concentrations are lower and R is higher (100.66) in non-smokers (n=184) than in smokers (n=117, R=36.54). Non-smokers have lower S-PMA and a higher R in GSTT1 null genotypes than in positive, and a higher S-PMA and a lower R in GSTA1 wild type genotypes. In smokers the GSTT1 null genotype effect on both S-PMA and R is confirmed, and is also shown in GSTM1 null, but not in GSTA1 wild type genotypes. GSTT1 null polymorphism reduces the conjugation rate of benzene epoxide with GSH, and to a lesser extent also GSTTA1 mutant, GSTM1 null and NQO1 mutant genotypes. The activity of one GST is compensated by another in GSTM1 and GSTA1 defective subjects, but not in GSTT1 null genotypes, whose average S-PMA excretion is about 50% with respect to the positive ones, for the same benzene exposure. R showed to be a more sensitive marker for these effects than the metabolite levels.

  20. Quantum magnetic deflagration in acetate.

    PubMed

    Hernández-Mínguez, A; Hernandez, J M; Macià, F; García-Santiago, A; Tejada, J; Santos, P V

    2005-11-18

    We report controlled ignition of magnetization reversal avalanches by surface acoustic waves in a single crystal of acetate. Our data show that the speed of the avalanche exhibits maxima on the magnetic field at the tunneling resonances of Mn(12). Combined with the evidence of magnetic deflagration in Mn(12) acetate, this suggests a novel physical phenomenon: deflagration assisted by quantum tunneling. PMID:16384178

  1. Quantum magnetic deflagration in acetate.

    PubMed

    Hernández-Mínguez, A; Hernandez, J M; Macià, F; García-Santiago, A; Tejada, J; Santos, P V

    2005-11-18

    We report controlled ignition of magnetization reversal avalanches by surface acoustic waves in a single crystal of acetate. Our data show that the speed of the avalanche exhibits maxima on the magnetic field at the tunneling resonances of Mn(12). Combined with the evidence of magnetic deflagration in Mn(12) acetate, this suggests a novel physical phenomenon: deflagration assisted by quantum tunneling.

  2. Standardization of Spore Inactivation Method for PMA-PhyloChip Analysis

    NASA Technical Reports Server (NTRS)

    Schrader, Michael

    2011-01-01

    In compliance with the Committee on Space Research (COSPAR) planetary protection policy, National Aeronautics and Space Administration (NASA) monitors the total microbial burden of spacecraft as a means for minimizing the inadvertent transfer of viable contaminant microorganisms to extraterrestrial environments (forward contamination). NASA standard assay-based counts are used both as a proxy for relative surface cleanliness and to estimate overall microbial burden as well as to assess whether forward planetary protection risk criteria are met for a given mission, which vary by the planetary body to be explored and whether or not life detection missions are present. Despite efforts to reduce presence of microorganisms from spacecraft prior to launch, microbes have been isolated from spacecraft and associated surfaces within the extreme conditions of clean room facilities using state of the art molecular technologies. Development of a more sensitive method that will better enumerate all viable microorganisms from spacecraft and associated surfaces could support future life detection missions. Current culture-based (NASA standard spore assay) and nucleic-acid-based polymerase chain reaction (PCR) methods have significant shortcomings in this type of analysis. The overall goal of this project is to evaluate and validate a new molecular method based on the use of a deoxyribonucleic acid (DNA) intercalating agent propidium monoazide (PMA). This is used in combination with DNA microarray (PhyloChip) which has been shown to identify very low levels of organisms on spacecraft associated surfaces. PMA can only penetrate the membrane of dead cells. Once penetrated, it intercalates the DNA and, upon photolysis using visible light it produces stable DNA monoadducts. This allows DNA to be unavailable for further PCR analysis. The specific aim of this study is to standardize the spore inactivation method for PMA-PhyloChip analysis. We have used the bacterial spores Bacillus

  3. The PMA-1 arrives in the SSPF prior to its attachment to Node 1

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The first of two Pressurized Mating Adapters, or PMAs, for the International Space Station arrive in KSC's Space Station Processing Facility in July. A PMA is a cone-shaped connector that will be attached to Node 1, the space station's structural building block, during ground processing. The adapter will house space station computers and various electrical support equipment and eventually will serve as the passageway for astronauts between the node and the U.S-financed, Russian-built Functional Cargo Block. Node 1 with two adapters attached will be the first element of the station to be launched aboard the Space Shuttle Endeavour on STS-88 in July 1998.

  4. Scaffolding is erected around the PMA-1 in the SSPF prior to its attachment to Node 1

    NASA Technical Reports Server (NTRS)

    1997-01-01

    International Space Station (ISS) contractors erect access scaffolding around the Pressurized Mating Adapter-1 (PMA-1) for the ISS in KSC's Space Station Processing Facility. A PMA is a cone-shaped connector that will be attached to Node 1, the space station's structural building block, during ground processing. The white flight cables around PMA-1 will assist in connecting the node to the U.S.-financed, Russian-built Functional Cargo Block, a component that supplies early power and propulsion systems for the station. Node 1 with two adapters attached will be the first element of the station to be launched aboard the Space Shuttle Endeavour on STS-88 in July 1998.

  5. Isolating, immunophenotyping and ex vivo stimulation of CD4+ and CD8+ gastric lymphocytes during murine Helicobacter pylori infection

    PubMed Central

    Ruiz, Victoria E.; Sachdev, Monisha; Zhang, Songhua; Wen, Sicheng; Moss, Steven F.

    2012-01-01

    Helicobacter pylori infection is associated with severe chronic inflammation, yet the host immune response is rarely able to clear the bacterium. Thymus derived lymphocyte populations such as T helper 1, T helper 17, and T regulatory cells are known to play important roles in the chronicity of H. pylori infection as well as contributing to ongoing gastric pathology. It is yet to be established how these immune cell populations interact in the gastric environment during H. pylori infection. Mouse models of infection offer an opportunity to investigate these interactions in detail. Flow cytometric analysis provides excellent lymphocyte characterization due to its high specificity, sensitivity and potential to perform multiple simultaneous measurements. However, this requires a viable enriched single cell suspension after adequate tissue dissociation, which poses a challenge due to the heterogeneity of gastric tissue. We have evaluated several isolation techniques and have optimized a protocol to isolate and enrich lymphocytes from the H. pylori-infected murine stomach. EDTA/DTT followed by collagenase IV digestion successfully dissociates an average of 1 × 107 cells per mouse. Further enrichment using lympholyte M gradient yields on average 4 × 106 CD45+ lymphocytes per stomach. Following isolation we compared lymphocyte stimulation by CD3/CD28, phorbol 12-myristate 13-acetate (PMA) and ionomycin or H. pylori lysate and determined that CD3/CD28 effectively induces stimulation of IFNγ and IL 17A, but impairs Foxp3 expression. Using an optimized protocol we observed a 2-fold increase of CD8+ IFNγ-expressing lymphocytes localized specifically to the gastric compartment during H. pylori infection. The mechanisms of H. pylori immunopathogenesis are still considered enigmatic, therefore this optimized protocol can help delineate further novel immune cell targets that mediate H. pylori-induced pathology and identify the correlates of immunity for vaccine development

  6. Essential Role of Lysophosphatidylcholine Acyltransferase 3 in the Induction of Macrophage Polarization in PMA-Treated U937 Cells.

    PubMed

    Taniguchi, Kosuke; Hikiji, Hisako; Okinaga, Toshinori; Hashidate-Yoshida, Tomomi; Shindou, Hideo; Ariyoshi, Wataru; Shimizu, Takao; Tominaga, Kazuhiro; Nishihara, Tatsuji

    2015-12-01

    Lysophospholipid acyltransferases (LPLATs) regulate the diversification of fatty acid composition in biological membranes. Lysophosphatidylcholine acyltransferases (LPCATs) are members of the LPLATs that play a role in inflammatory responses. M1 macrophages differentiate in response to lipopolysaccharide (LPS) and are pro-inflammatory, whereas M2 macrophages, which differentiate in response to interleukin-4 (IL-4), are anti-inflammatory and involved in homeostasis and wound healing. In the present study, we showed that LPCATs play an important role in M1/M2-macrophage polarization. LPS changed the shape of PMA-treated U937 cells from rounded to spindle shaped and upregulated the mRNA and protein expression of the M1 macrophage markers CXCL10, TNF-α, and IL-1β. IL-4 had no effect on the shape of PMA-treated U937 cells and upregulated the M2 macrophage markers CD206, IL-1ra, and TGF-β in PMA-treated U937 cells. These results suggest that LPS and IL-4 promote the differentiation of PMA-treated U937 cells into M1- and M2-polarized macrophages, respectively. LPS significantly downregulated the mRNA expression of LPCAT3, one of four LPCAT isoforms, and suppressed its enzymatic activity toward linoleoyl-CoA and arachidonoyl-CoA in PMA-treated U937 cells. LPCAT3 knockdown induced a spindle-shaped morphology typical of M1-polarized macrophages, and increased the secretion of CXCL10 and decreased the levels of CD206 in IL-4-activated U937 cells. This indicates that knockdown of LPCAT3 shifts the differentiation of PMA-treated U937 cells to M1-polarized macrophages. Our findings suggest that LPCAT3 plays an important role in M1/M2-macrophage polarization, providing novel potential therapeutic targets for the regulation of immune and inflammatory disorders.

  7. Optimal Method to Stimulate Cytokine Production and Its Use in Immunotoxicity Assessment

    PubMed Central

    Ai, Wenchao; Li, Haishan; Song, Naining; Li, Lei; Chen, Huiming

    2013-01-01

    Activation of lymphocytes can effectively produce a large amount of cytokines. The types of cytokines produced may depend on stimulating reagents and treatments. To find an optimal method to stimulate cytokine production and evaluate its effect on immunotoxicity assessments, the authors analyzed production of IL-2, IL-4, IL-6, IL-10, IL-13, IFN-γ, TNF-α, GM-CSF, RANTES and TGF-β in undiluted rat whole blood culture (incubation for 0, 2, 4, 6, 8 or 10 h) with different concentrations of PMA/ionomycin, PHA, Con A, LPS and PWM. We also evaluated the effects of cyclosporin A and azathioprine on cytokine production. The results revealed a rapid increase of IL-2, IFN-γ, TNF-α, RANTES and TGF-β secretion within 6 h after stimulation with 25 ng/mL PMA and 1 μg/mL ionomycin. The inhibition of these cytokine profiles reflected the effects of immunosuppressants on the immune system. Therefore, the results of this is study recommend the detection of cytokine profiles in undiluted whole blood stimulated 6 h with 25 ng/mL PMA and 1 μg/mL ionomycin as a powerful immunotoxicity assessment method. PMID:23985769

  8. Multiple genetic control of acetate-induced olfactory responses in Drosophila melanogaster larvae.

    PubMed

    Cobb, M; Dannet, F

    1994-10-01

    Behavioural responses of Drosophila melanogaster larvae were measured in response to olfactory stimulation with an homologous series of eight aliphatic n-acetates (methyl ... octyl acetate) and with cis-vaccenyl acetate. Larvae tended to be attracted to short-chain acetates (methyl ... pentyl) and repelled by longer chain acetates (hexyl, heptyl and octyl acetate). All larvae were strongly attracted to propyl acetate, irrespective of the dose studied. Larval olfactory responses generally declined with age. Two geographical strains showed specific anosmias. Katsunuma (Japan) larvae showed no response to hexyl acetate; chromosome substitution showed this behaviour to be controlled by genes on chromosome II. Tai (Ivory Coast) larvae showed no response to pentyl acetate; chromosome substitution showed that two genetic factors were primarily involved, on the X chromosome and chromosome III. The response was modulated by chromosome II. No effect of the Y chromosome was found. Two olfactory mutants were studied, olfC (X chromosome) and Indf (chromosome III); both mutants showed abnormal responses to certain acetates. The results are discussed in terms of various models of olfactory processing and the implications of these models for the number of genes involved in olfaction. PMID:7989222

  9. 21 CFR 814.9 - Confidentiality of data and information in a premarket approval application (PMA) file.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ..., DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PREMARKET APPROVAL OF MEDICAL DEVICES... the safety and effectiveness of the device that is the subject of the PMA and that is the basis for... under § 20.61; and (ii) Any personnel, medical, and similar information disclosure of which...

  10. 21 CFR 814.9 - Confidentiality of data and information in a premarket approval application (PMA) file.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... a color additive petition submitted as part of a PMA is governed by § 71.15. (b) The existence of a... secret or confidential commercial or financial information under § 20.61. (3) Any adverse reaction report...: (i) Any information that constitutes trade secret or confidential commercial or financial...

  11. Pilomyxoid Astrocytoma (PMA) Shows Significant Differences in Gene Expression vs. Pilocytic Astrocytoma (PA) and Variable Tendency Toward Maturation to PA.

    PubMed

    Kleinschmidt-DeMasters, Bette K; Donson, Andrew M; Vogel, Hannes; Foreman, Nicholas K

    2015-07-01

    Pilomyxoid astrocytomas (PMAs) manifest a more aggressive clinical course than pilocytic astrocytomas (PAs). Development of effective therapies demands a better biological understanding of PMA. We first conducted gene expression microarray analysis of 9 PMA and 13 PA from infra- and supratentorial sites. Unsupervised hierarchical clustering analysis demonstrated that tumors are grouped according to anatomic site, not diagnosis. Gene expression profiles were then contrasted between eight PMAs and six PAs, all supratentorial/hypothalamic/chiasmal. Clinical outcome of PMAs varied, with four out of four patients with diencephalic syndrome succumbing to disease, one of whom showed bulky metastatic leptomeningeal spread at autopsy, with bimodal maturation to PA in some areas and de-differentiation to glioblastoma in others. A surviving child has undergone multiple surgical debulking, with progressive maturation to PA over time. Ontology-enrichment analysis identified overexpression in PMAs of extracellular matrix and mitosis-related genes. Genes overexpressed in PMA vs. PA, ranked according to fold-change, included developmental genes H19, DACT2, extracellular matrix collagens (COL2A1; COL1A1) and IGF2BP3 (IMP3), the latter previously identified as an adverse prognostic factor in PMA and PA.

  12. Pilomyxoid astrocytoma (PMA) shows significant differences in gene expression versus pilocytic astrocytoma (PA) and variable tendency toward maturation to PA

    PubMed Central

    Kleinschmidt-DeMasters, B.K.; Donson, Andrew M.; Vogel, Hannes; Foreman, Nicholas K.

    2015-01-01

    Pilomyxoid astrocytomas (PMAs) manifest a more aggressive clinical course than pilocytic astrocytomas (PAs). Development of effective therapies demands a better biological understanding of PMA. We first conducted gene expression microarray analysis of 9 PMA and 13 PA from infra- and supra-tentorial sites. Unsupervised hierarchical clustering analysis demonstrated that tumors grouped according to anatomic site, not diagnosis. Gene expression profiles were then contrasted between 8 PMAs and 6 PAs, all supratentorial/hypothalamic/chiasmal. Clinical outcome of PMAs varied, with 4/4 patients with diencephalic syndrome succumbing to disease, one of whom showed bulky metastatic leptomeningeal spread at autopsy, with bimodal maturation to PA in some areas and de-differentiation to glioblastoma in others. A surviving child has undergone multiple surgical debulkings, with progressive maturation to PA over time. Ontology-enrichment analysis identified overexpression in PMAs of extracellular matrix and mitosis-related genes. Genes overexpressed in PMA versus PA, ranked according to fold-change, included developmental genes H19, DACT2, extracellular matrix collagens (COL2A1;COL1A1) and IGF2BP3 (IMP3), the latter previously identified as an adverse prognostic factor in PMA and PA. PMID:25521223

  13. Ritanserin-sensitive receptors modulate the prosocial and the anxiolytic effect of MDMA derivatives, DOB and PMA, in zebrafish.

    PubMed

    Ponzoni, Luisa; Sala, Mariaelvina; Braida, Daniela

    2016-11-01

    Little is known about the pharmacological effects of amphetamine derivatives. In the present study, the effect on social preference and anxiety-like behavior of 2,5-dimetoxy-4-bromo-amphetamine hydrobromide (DOB) and para-methoxyamphetamine (PMA), in comparison with 3,4 methylenedioxymethamphetamine (MDMA) was investigated in zebrafish, an emerging model to study emotional behavior in an inexpensive and quick manner. DOB (0.05-2mg/kg), PMA (0.0005-2mg/kg) or MDMA (0.25-20mg/kg), given i.m. to adult zebrafish, progressively increased the time spent in the proximity of nacre fish picture in a social preference test. However, high doses were ineffective. Similarly, in the novel tank diving and light-dark tests the compounds elicited a progressive anxiolytic effect in terms of time spent in the upper half of the tank and in the light compartment, respectively. All the above effects were interpolated by symmetrical parabolas. The 5-HT2A/C antagonist ritanserin (0.025-2.5mg/kg) in association with the maximal effective dose of MDMA, DOB and PMA blocked both the social and anxiolytic effect. Taken together these findings demonstrate for the first time the prosocial and anxiolytic properties of DOB and PMA and focus on the mechanisms of their action through the serotonergic-like system suggesting a potential clinical application. PMID:27506653

  14. Complete genome sequence of Paracoccus marcusii phage vB_PmaS-R3 isolated from the South China Sea.

    PubMed

    Xu, Yongle; Zhang, Rui; Jiao, Nianzhi

    2015-01-01

    Paracoccus spp. are isolated from both terrestrial and aquatic habitats, indicating their ubiquitous existence in the environment. Here we present the first phage isolated from this genus, vB_PmaS-R3, and its complete genome sequence. Paracoccus phage vB_PmaS-R3 is a siphophage isolated from the South China Sea. The genome sequence is 42,093 bp, with a G + C content of 56.36 %. Fifty-two open reading frames were predicted from the genome. The genome can mainly be divided into three regions: genes for DNA metabolism, regulatory genes and structure forming genes. Genes encoding DNA metabolism and structural proteins showed high sequence homology to corresponding genes of Burkholderia phage KL1 and Pseudomonas phage PA73. In addition, four gene transfer agent-like genes were found in the vB_PmaS-R3 genome. A putative L-alanoyl-D-glutamate peptidase was predicted as the endolysin. A MazG gene was found in the vB_PmaS-R3 genome, which indicates genomic adaption to the nutrient-limited marine environment.

  15. Quantifying fungal viability in air and water samples using quantitative PCR after treatment with propidium monoazide (PMA)

    SciTech Connect

    Vesper, Stephen; McKinstry, Craig A.; Hartmann, Chris; Neace, Michelle; Yoder, Stephanie; Vesper, Alex

    2007-11-28

    A method is described to discriminate between live and dead cells of the infectious fungi Aspergillus fumigatus, Aspergillus flavus, Aspergillus terreus, Mucor racemosus, Rhizopus stolonifer and Paecilomyces variotii. To test the method, conidial suspensions were heat inactivated at 85 °C or held at 5 °C (controls) for 1 h. Polycarbonate filters (25 mm diameter, 0.8 μm pore size) were placed on "welled" slides (14 mm diameter) and the filters treated with either PBS or PMA. Propidium monoazide (PMA), which enters dead cells but not live cells, was incubated with cell suspensions, exposed to blue wavelength light-emitting diodes (LED) to inactivate remaining PMA and secure intercalation of PMAwith DNA of dead cells. Treated cells were extracted and the live and dead cells evaluated with quantitative PCR (QPCR). After heat treatment and DNA modification with PMA, all fungal species tested showed an approximate 100- to 1000-fold difference in cell viability estimated by QPCR analysis which was consistent with estimates of viability based on culturing.

  16. 21 CFR 173.228 - Ethyl acetate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... the specifications of the Food Chemicals Codex, 1 (Ethyl Acetate; p. 372, 3d Ed., 1981), which are... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ethyl acetate. 173.228 Section 173.228 Food and..., Lubricants, Release Agents and Related Substances § 173.228 Ethyl acetate. Ethyl acetate (CAS Reg. No....

  17. 21 CFR 173.228 - Ethyl acetate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... the specifications of the Food Chemicals Codex, 1 (Ethyl Acetate; p. 372, 3d Ed., 1981), which are... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethyl acetate. 173.228 Section 173.228 Food and..., Lubricants, Release Agents and Related Substances § 173.228 Ethyl acetate. Ethyl acetate (CAS Reg. No....

  18. 21 CFR 73.2396 - Lead acetate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 1 2014-04-01 2014-04-01 false Lead acetate. 73.2396 Section 73.2396 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2396 Lead acetate. (a) Identity. The color additive lead acetate is the trihydrate of lead (2+) salt of acetic acid. The color additive has the chemical formula...

  19. 21 CFR 73.2396 - Lead acetate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Lead acetate. 73.2396 Section 73.2396 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2396 Lead acetate. (a) Identity. The color additive lead acetate is the trihydrate of lead (2+) salt of acetic acid. The color additive has the chemical formula...

  20. 21 CFR 73.2396 - Lead acetate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Lead acetate. 73.2396 Section 73.2396 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2396 Lead acetate. (a) Identity. The color additive lead acetate is the trihydrate of lead (2+) salt of acetic acid. The color additive has the chemical formula...

  1. 21 CFR 73.2396 - Lead acetate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Lead acetate. 73.2396 Section 73.2396 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2396 Lead acetate. (a) Identity. The color additive lead acetate is the trihydrate of lead (2+) salt of acetic acid. The color additive has the chemical formula...

  2. 21 CFR 73.2396 - Lead acetate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Lead acetate. 73.2396 Section 73.2396 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2396 Lead acetate. (a) Identity. The color additive lead acetate is the trihydrate of lead (2+) salt of acetic acid. The color additive has the chemical formula...

  3. Kinetics of dissociation of thorium(IV) bound to PMA and PMVEMA

    SciTech Connect

    Choppin, G.R.; Cacheris, W. )

    1990-04-04

    The kinetics of dissociation of Th(IV) from its complexes with polymaleic acid (PMA) and poly(methyl vinyl ether) maleic acid (PMVEMA) were found to follow rate expressions that reflected seven separate terms ranging in lifetimes between 0.1 s and almost 1 h. The fraction of thorium dissociating by any one of the seven paths depended on the length of time during the first 2 days that the thorium had been bound to the polyelectrolyte prior to dissociation. After 48 h of binding, no further change was observed in the dissociation kinetics. These observations are interpreted in terms of the present models of metal-polyelectrolyte interaction. 10 refs., 2 figs., 4 tabs.

  4. 21 CFR 184.1185 - Calcium acetate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Calcium acetate. 184.1185 Section 184.1185 Food... GRAS § 184.1185 Calcium acetate. (a) Calcium acetate (Ca (C2H3O2)2, CAS Reg. No. 62-54-4), also known as acetate of lime or vinegar salts, is the calcium salt of acetic acid. It may be produced by...

  5. 21 CFR 184.1185 - Calcium acetate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Calcium acetate. 184.1185 Section 184.1185 Food and... Substances Affirmed as GRAS § 184.1185 Calcium acetate. (a) Calcium acetate (Ca (C2H3O2)2, CAS Reg. No. 62-54-4), also known as acetate of lime or vinegar salts, is the calcium salt of acetic acid. It may...

  6. 21 CFR 184.1185 - Calcium acetate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Calcium acetate. 184.1185 Section 184.1185 Food... Specific Substances Affirmed as GRAS § 184.1185 Calcium acetate. (a) Calcium acetate (Ca (C2H3O2)2, CAS Reg. No. 62-54-4), also known as acetate of lime or vinegar salts, is the calcium salt of acetic acid....

  7. 21 CFR 184.1185 - Calcium acetate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Calcium acetate. 184.1185 Section 184.1185 Food... Specific Substances Affirmed as GRAS § 184.1185 Calcium acetate. (a) Calcium acetate (Ca (C2H3O2)2, CAS Reg. No. 62-54-4), also known as acetate of lime or vinegar salts, is the calcium salt of acetic acid....

  8. 21 CFR 184.1185 - Calcium acetate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Calcium acetate. 184.1185 Section 184.1185 Food... Specific Substances Affirmed as GRAS § 184.1185 Calcium acetate. (a) Calcium acetate (Ca (C2H3O2)2, CAS Reg. No. 62-54-4), also known as acetate of lime or vinegar salts, is the calcium salt of acetic acid....

  9. 40 CFR 721.10001 - 2-Ethoxyethanol, 2-ethoxyethanol acetate, 2-methoxyethanol, and 2-methoxyethanol acetate.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... acetate, 2-methoxyethanol, and 2-methoxyethanol acetate. 721.10001 Section 721.10001 Protection of...-ethoxyethanol acetate, 2-methoxyethanol, and 2-methoxyethanol acetate. (a) Chemical substances and significant...-80-5), 2-ethoxyethanol acetate (CAS No. 111-15-9), 2-methoxyethanol (CAS No. 109-86-4), and...

  10. Differential inhibitory effects of 2-azafluorenones on PI-PLC activation but not on PC-PLC- or PC-PLD-activation induced by histamine, PAF, PMA or A23187 in C6 glioma cells.

    PubMed

    Wang, Hai-Long; Wang, Li-Chuan; Wei, Jiann-Wu

    2013-02-28

    In this study, C6 glioma cells were used to test the effects of 2-azafluorenone and its related compounds on membrane phosphatidylinositol (PI) and phosphatidylcholine (PC) turnover. An increase of [³H]-labeled inositol phosphate (IP1) formation by histamine (100 μM) or A23187 (100 nM) via the activation of phosphatidylinositol-specific phospholipase C (PI-PLC) to breakdown labeled substrate was observed, and this effect could be partially blocked by about half at 100 μM of 2-azafluorenones. Histamine induced the increase of IP1 formation, but failed to cause an increase in extracellularly releasing of [3H]choline metabolites, or intracellular accumulation of [³H]phosphscholine. However, platelet activation factor (PAF) from 0.2 to 1 μM, and phorbol 12-myristate-13-acetate (PMA) at 1 μM caused an increase in extracellularly releasing of [³H]choline metabolites, and intracellular accumulation of [³H]phosphocholine via the activation on phosphatidylcholine (PC)-PLC. These responses of PAF and PMA were not affected by 2-azafluorenone or 4-methyl-2-azafluorenone even at high concentration (10⁻⁴ M). A23187 induced an increase of intracellular [³H]choline release via the activation of PCphospholipase D (PLD). This increasing effect of 100 nM A23187 was not affected by 2-azafluorenone or 4-methyl-2-azafluorenone even at a high concentration of 10⁻⁴ M. In summary, the inhibitory effect of 2-azafluorenone and its related compound 4-methyl-2-azafluorenone was observed selectively on PIPLC, but not on PC-PLC or PC-PLD based on changes of products after the activation of these enzymes.

  11. Analysis of proteins responsive to acetic acid in Acetobacter: molecular mechanisms conferring acetic acid resistance in acetic acid bacteria.

    PubMed

    Nakano, Shigeru; Fukaya, Masahiro

    2008-06-30

    Acetic acid bacteria are used for industrial vinegar production because of their remarkable ability to oxidize ethanol and high resistance to acetic acid. Although several molecular machineries responsible for acetic acid resistance in acetic acid bacteria have been reported, the entire mechanism that confers acetic acid resistance has not been completely understood. One of the promising methods to elucidate the entire mechanism is global analysis of proteins responsive to acetic acid by two-dimensional gel electrophoresis. Recently, two proteins whose production was greatly enhanced by acetic acid in Acetobacter aceti were identified to be aconitase and a putative ABC-transporter, respectively; furthermore, overexpression or disruption of the genes encoding these proteins affected acetic acid resistance in A. aceti, indicating that these proteins are involved in acetic acid resistance. Overexpression of each gene increased acetic acid resistance in Acetobacter, which resulted in an improvement in the productivity of acetic acid fermentation. Taken together, the results of the proteomic analysis and those of previous studies indicate that acetic acid resistance in acetic acid bacteria is conferred by several mechanisms. These findings also provide a clue to breed a strain having high resistance to acetic acid for vinegar fermentation.

  12. The benzene metabolite para-benzoquinone is genotoxic in human, phorbol-12-acetate-13-myristate induced, peripheral blood mononuclear cells at low concentrations.

    PubMed

    Westphal, Götz Alexander; Bünger, Jürgen; Lichey, Nadine; Taeger, Dirk; Mönnich, Angelika; Hallier, Ernst

    2009-07-01

    Benzene is one of the most prominent occupational and environmental pollutants. The substance is a proven human carcinogen that induces hematologic malignancies in humans, probably at even low doses. Yet knowledge of the mechanisms leading to benzene-induced carcinogenesis is still incomplete. Benzene itself is not genotoxic. The generation of carcinogenic metabolites involves the production of oxidized intermediates such as catechol, hydroquinone and para-benzoquinone (p-BQ) in the liver. Further activation to the ultimate carcinogenic intermediates is most probably catalyzed by myeloperoxidase (MPO). Yet the products of the MPO pathway have not been identified. If an oxidized benzene metabolite such as p-BQ was actually the precursor for the ultimate carcinogenic benzene metabolite and further activation proceeds via MPO mediated reactions, it should be possible to activate p-BQ to a genotoxic compound in vitro. We tested this hypothesis with phorbol-12-acetate-13-myristate (PMA) activated peripheral blood cells exposed to p-BQ, using the cytokinesis-block micronucleus test. Addition of 20-28 ng/ml PMA caused a significant increase of micronuclei at low and non-cytotoxic p-BQ concentrations between 0.04 and 0.2 microg/ml (0.37-1.85 microM). Thus with PMA or p-BQ alone no reproducible elevation of micronuclei was seen up to toxic concentrations. PMA and p-BQ induce micronuclei when administered jointly. Our results add further support to the hypothesis that MPO is a key enzyme in the activation of benzene. PMID:19212761

  13. [The tocopherol acetate and splenin correction of the immunological disorders in patients with viral hepatitis B].

    PubMed

    Frolov, V M; Peresadin, N A; Dekaliuk, I V; Pshenichnyĭ, I Ia

    1992-04-01

    Inclusion of tocopherol acetate and splenin into complex treatment of viral hepatitis B (VHB) ensures a marked immunomodulating effect consisting in control of T-lymphopenia, normalization of helper-suppressor ratio, reduction of circulating immune complexes and a tendency to restoration of normal ratio between separate fractions of immune complexes, stimulation of phagocytic activity of monocytes of the peripheral blood. Splenin and tocopherol acetate are recommended in the complex treatment of hepatitis B.

  14. [The effect of solubilized alpha-tocopherol acetate on resistance to experimental physical loading].

    PubMed

    Samoĭlov, A V; Seĭfulla, R D; Kamaev, N O; Tunitskaia, T A; Teplova, N P; Karmanovskiĭ, A Ia; Belous, M V

    1992-01-01

    A single intravenous injection of solubilized alpha-tocopherol acetate to Wistar male rats in doses of 25, 50 and 100 mg/kg noticeably increased the animals' working capacity. The stimulation effect appeared 18 hours after the injection and was observable for two weeks. Utilization of glucose reserves in bioenergy supply of muscle activity has been shown. The maintenance of the action for such a long time may be accounted for by high metabolic stability of solubilized alpha-tocopherol acetate.

  15. Reductive opening of carbohydrate phenylsulfonylethylidene (PSE) acetals.

    PubMed

    Chéry, Florence; Cabianca, Elena; Tatibouët, Arnaud; De Lucchi, Ottorino; Lindhorst, Thisbe K; Rollin, Patrick

    2015-11-19

    The phenylsulfonylethylidene (PSE) acetal is a relatively new protecting group in carbohydrate chemistry. However, carbohydrate-derived phenylsulfonylethylidene (PSE) acetals show a different behavior in reductive desulfonylation than simple symmetrical acetals. Here we have investigated various SET-type reaction conditions in order to open PSE acetals regioselectively and to produce chiral ω-hydroxyethenyl ethers. Whereas sodium amalgam leads to a mixture of regioisomeric vinyl ethers besides the ethylidene acetal, samarium iodide is suited for regioselective ring opening. This is shown with seven different carbohydrate PSE acetals, both of the 1,3-dioxane and the 1,3-dioxolane type. PMID:26469209

  16. Antioxidant and Antiradical Activities of Manihot esculenta Crantz (Euphorbiaceae) Leaves and Other Selected Tropical Green Vegetables Investigated on Lipoperoxidation and Phorbol-12-myristate-13-acetate (PMA) Activated Monocytes

    PubMed Central

    Tsumbu, Cesar N.; Deby-Dupont, Ginette; Tits, Monique; Angenot, Luc; Franck, Thierry; Serteyn, Didier; Mouithys-Mickalad, Ange

    2011-01-01

    Abelmoschus esculentus (Malvaceae), Hibiscus acetosella (Malvaceae), Manihot esculenta Crantz (Euphorbiaceae) and Pteridium aquilinum (Dennstaedtiaceae) leaves are currently consumed as vegetables by migrants from sub-Saharan Africa living in Western Europe and by the people in the origin countries, where these plants are also used in the folk medicine. Manihot leaves are also eaten in Latin America and some Asian countries. This work investigated the capacity of aqueous extracts prepared from those vegetables to inhibit the peroxidation of a linoleic acid emulsion. Short chain, volatile C-compounds as markers of advanced lipid peroxidation were measured by gas chromatography by following the ethylene production. The generation of lipid hydroperoxides, was monitored by spectroscopy using N-N′-dimethyl-p-phenylene-diamine (DMPD). The formation of intermediate peroxyl, and other free radicals, at the initiation of the lipid peroxidation was investigated by electron spin resonance, using α-(4-pyridyl-1-oxide)-N-tert-butylnitrone as spin trap agent. The ability of the extracts to decrease the cellular production of reactive oxygen species (ROS) in “inflammation like” conditions was studied by fluorescence technique using 2′,7′-dichlorofluorescine-diacetate as fluorogenic probe, in a cell model of human monocytes (HL-60 cells) activated with phorbol ester. Overall the extracts displayed efficient concentration-dependent inhibitory effects. Their total polyphenol and flavonoid content was determined by classic colorimetric methods. An HPLC-UV/DAD analysis has clearly identified the presence of some polyphenolic compounds, which explains at least partially the inhibitions observed in our models. The role of these plants in the folk medicine by sub-Saharan peoples as well as in the prevention of oxidative stress and ROS related diseases requires further consideration. PMID:22254126

  17. Antioxidant and antiradical activities of Manihot esculenta Crantz (Euphorbiaceae) leaves and other selected tropical green vegetables investigated on lipoperoxidation and phorbol-12-myristate-13-acetate (PMA) activated monocytes.

    PubMed

    Tsumbu, Cesar N; Deby-Dupont, Ginette; Tits, Monique; Angenot, Luc; Franck, Thierry; Serteyn, Didier; Mouithys-Mickalad, Ange

    2011-09-01

    Abelmoschus esculentus (Malvaceae), Hibiscus acetosella (Malvaceae), Manihot esculenta Crantz (Euphorbiaceae) and Pteridium aquilinum (Dennstaedtiaceae) leaves are currently consumed as vegetables by migrants from sub-Saharan Africa living in Western Europe and by the people in the origin countries, where these plants are also used in the folk medicine. Manihot leaves are also eaten in Latin America and some Asian countries. This work investigated the capacity of aqueous extracts prepared from those vegetables to inhibit the peroxidation of a linoleic acid emulsion. Short chain, volatile C-compounds as markers of advanced lipid peroxidation were measured by gas chromatography by following the ethylene production. The generation of lipid hydroperoxides, was monitored by spectroscopy using N-N'-dimethyl-p-phenylene-diamine (DMPD). The formation of intermediate peroxyl, and other free radicals, at the initiation of the lipid peroxidation was investigated by electron spin resonance, using α-(4-pyridyl-1-oxide)-N-tert-butylnitrone as spin trap agent. The ability of the extracts to decrease the cellular production of reactive oxygen species (ROS) in "inflammation like" conditions was studied by fluorescence technique using 2',7'-dichlorofluorescine-diacetate as fluorogenic probe, in a cell model of human monocytes (HL-60 cells) activated with phorbol ester. Overall the extracts displayed efficient concentration-dependent inhibitory effects. Their total polyphenol and flavonoid content was determined by classic colorimetric methods. An HPLC-UV/DAD analysis has clearly identified the presence of some polyphenolic compounds, which explains at least partially the inhibitions observed in our models. The role of these plants in the folk medicine by sub-Saharan peoples as well as in the prevention of oxidative stress and ROS related diseases requires further consideration.

  18. Antioxidant and antiradical activities of Manihot esculenta Crantz (Euphorbiaceae) leaves and other selected tropical green vegetables investigated on lipoperoxidation and phorbol-12-myristate-13-acetate (PMA) activated monocytes.

    PubMed

    Tsumbu, Cesar N; Deby-Dupont, Ginette; Tits, Monique; Angenot, Luc; Franck, Thierry; Serteyn, Didier; Mouithys-Mickalad, Ange

    2011-09-01

    Abelmoschus esculentus (Malvaceae), Hibiscus acetosella (Malvaceae), Manihot esculenta Crantz (Euphorbiaceae) and Pteridium aquilinum (Dennstaedtiaceae) leaves are currently consumed as vegetables by migrants from sub-Saharan Africa living in Western Europe and by the people in the origin countries, where these plants are also used in the folk medicine. Manihot leaves are also eaten in Latin America and some Asian countries. This work investigated the capacity of aqueous extracts prepared from those vegetables to inhibit the peroxidation of a linoleic acid emulsion. Short chain, volatile C-compounds as markers of advanced lipid peroxidation were measured by gas chromatography by following the ethylene production. The generation of lipid hydroperoxides, was monitored by spectroscopy using N-N'-dimethyl-p-phenylene-diamine (DMPD). The formation of intermediate peroxyl, and other free radicals, at the initiation of the lipid peroxidation was investigated by electron spin resonance, using α-(4-pyridyl-1-oxide)-N-tert-butylnitrone as spin trap agent. The ability of the extracts to decrease the cellular production of reactive oxygen species (ROS) in "inflammation like" conditions was studied by fluorescence technique using 2',7'-dichlorofluorescine-diacetate as fluorogenic probe, in a cell model of human monocytes (HL-60 cells) activated with phorbol ester. Overall the extracts displayed efficient concentration-dependent inhibitory effects. Their total polyphenol and flavonoid content was determined by classic colorimetric methods. An HPLC-UV/DAD analysis has clearly identified the presence of some polyphenolic compounds, which explains at least partially the inhibitions observed in our models. The role of these plants in the folk medicine by sub-Saharan peoples as well as in the prevention of oxidative stress and ROS related diseases requires further consideration. PMID:22254126

  19. Phosphatidylinositol 3-kinase, protein kinase B and ribosomal S6 kinases in the stimulation of thyroid epithelial cell proliferation by cAMP and growth factors in the presence of insulin.

    PubMed

    Coulonval, K; Vandeput, F; Stein, R C; Kozma, S C; Lamy, F; Dumont, J E

    2000-06-01

    The proliferation of most normal cells depends on the co-operation of several growth factors and hormones, each with a specific role, but the key events involved in the action of each necessary stimulant remain largely uncharacterized. In the present study, the pathways involved in the mechanism(s) of co-operation have been investigated in primary cultures of dog thyroid epithelial cells. In this physiologically relevant system, thyroid stimulating hormone (TSH) acting through cAMP, epidermal growth factor (EGF) and phorbol esters (such as PMA) induce DNA synthesis. Their effect requires stimulation of the insulin-like growth factor-1 (IGF-1) receptor by either IGF-1 or insulin, which are not themselves mitogenic agents. In contrast, hepatocyte growth factor (HGF) is itself fully mitogenic. The results of the study demonstrate that cAMP, EGF, HGF and PMA stimulate p70 ribosomal S6 kinase (p70 S6 kinase). However, insulin/IGF-1 also stimulate p70 S6 kinase. Thus stimulation of p70 S6 kinase might be necessary, but is certainly not sufficient, for the induction of DNA synthesis and is not specific for any stimulated pathway. In contrast, phosphatidylinositol 3-kinase (PI 3-kinase) and protein kinase B (PKB) activation by insulin and HGF is strong and sustained, whereas it is weak and transient with EGF and absent in the presence of TSH or PMA. These findings suggest that: (i) stimulation of PI 3-kinases and/or PKB is not involved in the cAMP-dependent pathways leading to thyrocyte proliferation, or in the action of PMA, (ii) the stimulation of the PI 3-kinase/PKB pathway may account for the permissive action of insulin/IGF-1 in the proliferation of these cells, and (iii) the stimulation of this pathway by HGF may explain why this agent does not require insulin or IGF-1 for its mitogenic action. PMID:10816429

  20. Carbon-isotopic analysis of dissolved acetate

    NASA Technical Reports Server (NTRS)

    Gelwicks, J. T.; Hayes, J. M.

    1990-01-01

    Heating of dried, acetate-containing solids together with oxalic acid dihydrate conveniently releases acetic acid for purification by gas chromatography. For determination of the carbon-isotopic composition of total acetate, the acetate-containing zone of the chromatographic effluent can be routed directly to a combustion furnace coupled to a vacuum system allowing recovery, purification, and packaging of CO2 for mass-spectrometric analysis. For analysis of methyl carbon, acetic acid can be cryogenically trapped from the chromatographic effluent, then transferred to a tube containing excess NaOH. The tube is evacuated, sealed, and heated to 500 degrees C to produce methane by pyrolysis of sodium acetate. Subsequent combustion of the methane allows determination of the 13C content at the methyl position in the parent acetate. With typical blanks, the standard deviation of single analyses is less than 0.4% for acetate samples larger than 5 micromoles. A full treatment of uncertainties is outlined.

  1. Ozone decomposition in aqueous acetate solutions

    SciTech Connect

    Sehested, K.; Holcman, J.; Bjergbakke, E.; Hart, E.J.

    1987-01-01

    The acetate radical ion reacts with ozone with a rate constant of k = (1.5 +/- 0.5) x 10Z dmT mol s . The products from this reaction are CO2, HCHO, and O2 . By subsequent reaction of the peroxy radical with ozone the acetate radical ion is regenerated through the OH radical. A chain decomposition of ozone takes place. It terminates when the acetate radical ion reacts with oxygen forming the unreactive peroxy acetate radical. The chain is rather short as oxygen is developed, as a result of the ozone consumption. The inhibiting effect of acetate on the ozone decay is rationalized by OH scavenging by acetate and successive reaction of the acetate radical ion with oxygen. Some products from the bimolecular disappearance of the peroxy acetate radicals, however, react further with ozone, reducing the effectiveness of the stabilization.

  2. Acetate transport across the intestinal epithelium of an herbivorous teleost. [Oreochromis mossambicus

    SciTech Connect

    Titus, E.; Ahearn, G.A. )

    1990-02-26

    {sup 3}H-acetate transport across the upper intestine of the tilapia, Oreochromis mossabicus, using brush border and basolateral membrane vesicles, and intestinal sheets mounted in modified Ussing chambers was investigated. Brush border and basolateral vesicles demonstrated qualitatively similar anion antiport activity where, in the presence of a full profile of organic and inorganic anions, volatile fatty acids (VFA; acetate, propionate, butyrate) and bicarbonate showed reciprocal trans-stimulation and cis-inhibition of {sup 3}H-acetate influx, suggesting both membranes had the same VFA/bicarbonate exchange mechanism. Kinetic analysis of {sup 3}H-acetate influx into brush border and basolateral vesicles revealed different half-saturation constants (Km) as a function of external acetate concentrations (6.43 mM and 11.91 mM, respectively) and as a function of internal bicarbonate (5.89 mM and 0.41 mM, respectively). Intestinal sheets supported net absorptive fluxes when serosal acetate concentrations were held steady at 1.0 mM and mucosal acetate was varied from 1.60 to 10.0 mM. Unidirectional fluxes were significantly diminished by the addition of acetazolamide. This study postulates a transcellular transport pathway for VFA whereby qualitatively similar antiporters in series lead to a downhill flow of luminal acetate to the blood, which is driven by intracellular carbonic anhydrase and a transmural VFA concentration gradient.

  3. [Evaluation of pathogen disinfection efficacy by chlorine and monochloramine disinfection based on quantitative PCR combined with propidium monoazide (PMA-qPCR)].

    PubMed

    Tong, Tie-Zheng; Wu, Shu-Xu; Li, Dan; He, Miao; Yang, Tian; Shi, Han-Chang

    2011-04-01

    A novel detection method of quantitative PCR combined with a DNA intercalating dye propidium monoazide (PMA-qPCR) was developed and then applied to analyze inactivation efficacy of chlorine and monochloramine on E. coli as a representative organism. The results shows that PMA removed 99.94% and 99.99% DNA from non-viable E. coli and Salmonella cells respectively and PMA-qPCR could effectively differentiate viable bacteria from non-viable bacteria; According to the first-order kinetic model, the inactivation coefficients on E. coli obtained by PMA-qPCR were 2.24 L x (mg x min)-1 and 0.0175 L x (mg x min)-1 for chlorine and monochloramine respectively, both of which were lower than those obtained by traditional plating counting method. In order to inactivate 99% of E. coli, the ct values by PMA-qPCR were 0.9 mg L(-1) min and more than 100 mg x L(-1) x min for chlorine and monochloramine while those by plating counting method were only 0.6 mg x L(-1) x min and 20 mg x L(-1) min, respectively; E. coli concentration detected by conventional qPCR kept almost the same when ct value increased, indicating that conventional qPCR was unable to evaluate inactivation efficacy of both chlorine and monochloramine disinfection. In summary, PMA-qPCR shows to be a promising method for evaluating disinfection efficacy by chlorine and monochloramine more accurately.

  4. A Genetic Screen for Pathogenicity Genes in the Hemibiotrophic Fungus Colletotrichum higginsianum Identifies the Plasma Membrane Proton Pump Pma2 Required for Host Penetration

    PubMed Central

    Dahl, Marlis; Müller, Susanne; Voll, Lars M.; Koch, Christian

    2015-01-01

    We used insertional mutagenesis by Agrobacterium tumefaciens mediated transformation (ATMT) to isolate pathogenicity mutants of Colletotrichum higginsianum. From a collection of 7200 insertion mutants we isolated 75 mutants with reduced symptoms. 19 of these were affected in host penetration, while 17 were affected in later stages of infection, like switching to necrotrophic growth. For 16 mutants the location of T-DNA insertions could be identified by PCR. A potential plasma membrane H+-ATPase Pma2 was targeted in five independent insertion mutants. We genetically inactivated the Ku80 component of the non-homologous end-joining pathway in C. higginsianum to establish an efficient gene knockout protocol. Chpma2 deletion mutants generated by homologous recombination in the ΔChku80 background form fully melanized appressoria but entirely fail to penetrate the host tissue and are non-pathogenic. The ChPMA2 gene is induced upon appressoria formation and infection of A. thaliana. Pma2 activity is not important for vegetative growth of saprophytically growing mycelium, since the mutant shows no growth penalty under these conditions. Colletotrichum higginsianum codes for a closely related gene (ChPMA1), which is highly expressed under most growth conditions. ChPMA1 is more similar to the homologous yeast genes for plasma membrane pumps. We propose that expression of a specific proton pump early during infection may be common to many appressoria forming fungal pathogens as we found ChPMA2 orthologs in several plant pathogenic fungi. PMID:25992547

  5. 21 CFR 184.1721 - Sodium acetate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Sodium acetate. 184.1721 Section 184.1721 Food and....1721 Sodium acetate. (a) Sodium acetate (C2H3O2Na, CAS Reg. No. 127-09-3 or C2H3O2Na·3H2O, CAS Reg. No. 6131-90-4) is the sodium salt of acetic acid and occurs naturally in plant and animal tissues....

  6. 21 CFR 582.1721 - Sodium acetate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Sodium acetate. 582.1721 Section 582.1721 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1721 Sodium acetate. (a) Product. Sodium acetate. (b) Conditions of use. This substance is...

  7. 21 CFR 582.1721 - Sodium acetate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Sodium acetate. 582.1721 Section 582.1721 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1721 Sodium acetate. (a) Product. Sodium acetate. (b) Conditions of use. This substance is...

  8. 21 CFR 582.1721 - Sodium acetate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium acetate. 582.1721 Section 582.1721 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1721 Sodium acetate. (a) Product. Sodium acetate. (b) Conditions of use. This substance is...

  9. 21 CFR 582.1721 - Sodium acetate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Sodium acetate. 582.1721 Section 582.1721 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1721 Sodium acetate. (a) Product. Sodium acetate. (b) Conditions of use. This substance is...

  10. 21 CFR 582.1721 - Sodium acetate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Sodium acetate. 582.1721 Section 582.1721 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1721 Sodium acetate. (a) Product. Sodium acetate. (b) Conditions of use. This substance is...

  11. 21 CFR 556.380 - Melengestrol acetate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Melengestrol acetate. 556.380 Section 556.380 Food... Tolerances for Residues of New Animal Drugs § 556.380 Melengestrol acetate. A tolerance of 25 parts per billion is established for residues of the parent compound, melengestrol acetate, in fat of cattle....

  12. 21 CFR 582.6185 - Calcium acetate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Calcium acetate. 582.6185 Section 582.6185 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Calcium acetate. (a) Product. Calcium acetate. (b) Conditions of use. This substance is...

  13. 21 CFR 582.6185 - Calcium acetate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Calcium acetate. 582.6185 Section 582.6185 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Calcium acetate. (a) Product. Calcium acetate. (b) Conditions of use. This substance is...

  14. 21 CFR 582.6185 - Calcium acetate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Calcium acetate. 582.6185 Section 582.6185 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Calcium acetate. (a) Product. Calcium acetate. (b) Conditions of use. This substance is...

  15. 21 CFR 582.6185 - Calcium acetate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Calcium acetate. 582.6185 Section 582.6185 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Calcium acetate. (a) Product. Calcium acetate. (b) Conditions of use. This substance is...

  16. 21 CFR 582.6185 - Calcium acetate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Calcium acetate. 582.6185 Section 582.6185 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Calcium acetate. (a) Product. Calcium acetate. (b) Conditions of use. This substance is...

  17. 21 CFR 582.1005 - Acetic acid.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Acetic acid. 582.1005 Section 582.1005 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1005 Acetic acid. (a) Product. Acetic acid. (b) Conditions of use. This substance is...

  18. 21 CFR 582.1005 - Acetic acid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Acetic acid. 582.1005 Section 582.1005 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1005 Acetic acid. (a) Product. Acetic acid. (b) Conditions of use. This substance is...

  19. 21 CFR 582.1005 - Acetic acid.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Acetic acid. 582.1005 Section 582.1005 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1005 Acetic acid. (a) Product. Acetic acid. (b) Conditions of use. This substance is...

  20. 21 CFR 582.1005 - Acetic acid.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Acetic acid. 582.1005 Section 582.1005 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1005 Acetic acid. (a) Product. Acetic acid. (b) Conditions of use. This substance is...

  1. 21 CFR 582.1005 - Acetic acid.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Acetic acid. 582.1005 Section 582.1005 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1005 Acetic acid. (a) Product. Acetic acid. (b) Conditions of use. This substance is...

  2. Unity with PMA-2 attached awaits further processing in the SSPF

    NASA Technical Reports Server (NTRS)

    1998-01-01

    The International Space Station's (ISS) Unity node, with Pressurized Mating Adapter (PMA)-2 attached, awaits further processing by Boeing technicians in its workstand in the Space Station Processing Facility (SSPF). The Unity node is the first element of the ISS to be manufactured in the United States and is currently scheduled to lift off aboard the Space Shuttle Endeavour on STS-88 later this year. Unity has two PMAs attached to it now that this mate is completed. PMAs are conical docking adapters which will allow the docking systems used by the Space Shuttle and by Russian modules to attach to the node's hatches and berthing mechanisms. Once in orbit, Unity, which has six hatches, will be mated with the already orbiting Control Module and will eventually provide attachment points for the U.S. laboratory module; Node 3; an early exterior framework or truss for the station; an airlock; and a multi-windowed cupola. The Control Module, or Functional Cargo Block, is a U.S.-funded and Russian-built component that will be launched aboard a Russian rocket from Kazakstan.

  3. Unity with PMA-2 attached awaits further processing in the SSPF

    NASA Technical Reports Server (NTRS)

    1998-01-01

    The International Space Station's (ISS) Unity node, with Pressurized Mating Adapter (PMA)-2 attached, awaits further processing in the Space Station Processing Facility (SSPF). The Unity node is the first element of the ISS to be manufactured in the United States and is currently scheduled to lift off aboard the Space Shuttle Endeavour on STS-88 later this year. Unity has two PMAs attached to it now that this mate is completed. PMAs are conical docking adapters which will allow the docking systems used by the Space Shuttle and by Russian modules to attach to the node's hatches and berthing mechanisms. Once in orbit, Unity, which has six hatches, will be mated with the already orbiting Control Module and will eventually provide attachment points for the U.S. laboratory module; Node 3; an early exterior framework or truss for the station; an airlock; and a multi-windowed cupola. The Control Module, or Functional Cargo Block, is a U.S.- funded and Russian-built component that will be launched aboard a Russian rocket from Kazakstan.

  4. Photochemistry of 2-nitrobenzylidene acetals.

    PubMed

    Sebej, Peter; Solomek, Tomás; Hroudná, L'ubica; Brancová, Pavla; Klán, Petr

    2009-11-20

    Photolysis of dihydroxy compounds (diols) protected as 2-nitrobenzylidene acetals (ONBA) and subsequent acid- or base-catalyzed hydrolysis of the 2-nitrosobenzoic acid ester intermediates result in an efficient and high-yielding release of the substrates. We investigated the scope and limitations of ONBA photochemistry and expanded upon earlier described two-step procedures to show that the protected diols of many structural varieties can also be liberated in a one-pot procedure. In view of the fact that the acetals of nonsymmetrically substituted diols are converted into one of the corresponding 2-nitrosobenzoic acid ester isomers with moderate to high regioselectivity, the mechanism of their formation was studied using various experimental techniques. The experimental data were found to be in agreement with DFT-based quantum chemical calculations that showed the preferential cleavage occurs on the acetal C-O bond in the vicinity of more electron-withdrawing (or less electron-donating) groups. The study also revealed considerable complexity in the cleavage mechanism and that the structural variations in the substrate can significantly alter the reaction pathway. This deprotection strategy was found to be also applicable for 2-thioethanol when released from the corresponding monothioacetal in the presence of a reducing agent, such as ascorbic acid.

  5. Effect of lead acetate toxicity on experimental male albino rat

    PubMed Central

    Ibrahim, Nabil M; Eweis, Esam A; El-Beltagi, Hossam S; Abdel-Mobdy, Yasmin E

    2012-01-01

    Objective To evaluate the effect of different doses of lead acetate (1/20, 1/40 and 1/60 of LD50) on body weight gain, blood picture, plasma protein profile and the function of liver, kidney and thyroid gland. Methods Male albino rats were divided into four groups, the first group represented the health control animals, while the second, third and fourth groups were ingested orally with sub lethal doses of lead acetate (1/20, 1/40 and 1/60) of the oral LD50, respectively. One dose was ingested every two days during the experimental period (14 weeks) including the adaptation time. Blood was collected and used for all analysis. Results The results showed that, the ingestion of Pb2+ induced significant stimulation in glutamic-pyruvic transaminase (ALT) and glutamic-oxalacetic transaminease (AST) activity. Also, total soluble protein and albumin contents of plasma were significantly decreased, while the content of globulin was changed by the Pb2+ treatments. The cholinesterase activity was inhibited, but the activities of alkaline and acid phosphates and lactate dehydrogenase were stimulated, while plasma glucose level was elevated as a result of lead acetate intoxication. In case of blood picture, Pb2+ ingestion reduced the contents of hemoglobin and RBCs count of intoxicated rat's blood and the plasma levels of T3, T4 and blood WBCs count were decreased. Conclusions It can be concluded that lead acetate has harmful effect on experimental male albino rats. Therefore, the present work advises people to prevent exposure to the lead compound to avoid injurious hazard risk. PMID:23569832

  6. Biodegradation of cellulose acetate by Neisseria sicca.

    PubMed

    Sakai, K; Yamauchi, T; Nakasu, F; Ohe, T

    1996-10-01

    Bacteria capable of assimilating cellulose acetate, strains SB and SC, were isolated from soil on a medium containing cellulose acetate as a carbon source, and identified as Neisseria sicca. Both strains degraded cellulose acetate membrane filters (degree of substitution, DS, mixture of 2.8 and 2.0) and textiles (DS, 2.34) in a medium containing cellulose acetate (DS, 2.34) or its oligomer, but were not able to degrade these materials in a medium containing cellobiose octaacetate. Biodegradation of cellulose acetate (DS, 1.81 and 2.34) on the basis of biochemical oxygen demand reached 51 and 40% in the culture of N. sicca SB and 60 and 45% in the culture of N. sicca SC within 20 days. A decrease in the acetyl content of degraded cellulose acetate films and powder was confirmed by infrared and nuclear magnetic resonance analyses. After 10-day cultivation of N. sicca SB and SC, the number-average molecular weight of residual cellulose acetate decreased by 9 and 5%, respectively. Activities of enzymes that released acetic acid and produced reducing sugars from cellulose acetate were mainly present in the culture supernatant. Reactivity of enzymes for cellulose acetate (DS, 1.81) was higher than that for cellulose acetate (DS, 2.34).

  7. [Studies on cell signaling immunomodulated murine peritoneal suppressor macrophages: LPS and PMA mediate the activation of RAF-1, MAPK p44 and MAPK p42 and p38 MAPK].

    PubMed

    Chang, Z L; Lin, M Q; Wang, M Z; Yao, Z

    1997-03-01

    38 MAPK (mammalian equivalents of HOG1 in yeast) and JNK MAPK have been discovered. The requirement for activation of p38 MAPK for both Thr-180 and Tyr-182 (at TGY motif) has been shown. p38 MAPK is important in certain transcriptional regulatory pathways, since it can phosphorylate the following transcriptional factors: 1) Elk at Ser 383/389 for binding with SRE motif; 2). ATF 2 at Ser 69/71, forming a complex with Myc for DNA binding at CRE motif; 3) Max at Ser-62 to combine DNA of E-Box motif. p38 MAPK can be activated by LPS, inflammatory cytokines, such as TNF and IL-1, osmolarity. To examine the possibility that whether activation of Raf-1 and ERK 1, ERK2 and p38 MAPK can be regulated directly or/and differently by PKC and PKA pathways, herbimycin A (Ki = 0.9 mumol/L), a potent PTK inhibitor (J. Immunol. 155:3944-4003, 1995) at 2 mumol/L concentration was utilized to block Ras/Raf-1/MAPK cascade. After pre-incubation of macrophages with herbimycin A for 30 min or 90 min, cells were treated with LPS (10 micrograms/ml) and PMA (100 nmol/L) for 15 min. No inhibition of phosphorylation of Raf-1, MAPK p44 and MAPK p42 in response to LPS and PMA was observed (Fig. 1 and 3). However, forskolin, a cAMP inducer for protein kinase A (PKA) activation, inhibited the phosphorylation of LPS- and PMA-stimulated Raf-1, MAPK p44 and MAPK p42 (Fig. 2 and 4). Similarly, in agreement with a very recent report from David, M et al in NIH, in which they indicated that forskolin (30 mumol/L) inhibited IFN-beta-stimulated ERK activity by U 266 cells (J. Biol. Chem. 271: 4585-4588 1996), we found that the levels of phosphorylations of Raf-1 and ERK1 and ERK2 were declined when forskolin (30 mumol/L) was added to macrophages for 20 min at 37 degrees C prior to the stimulation by LPS and PMA. Interestingly, under the same condition, forskolin (30 mumol/L) stimulated the phosphorylation of LPS- and PMA-triggered p38 MAPK of murine peritoneal suppressor macrophages, suggesting that

  8. An Evaluation of Retentive Ability and Deformation of Acetal Resin and Cobalt-Chromium Clasps

    PubMed Central

    Meenakshi, A.; Gupta, Ranjana; Bharti, Vinay; Sriramaprabu, G.

    2016-01-01

    Aim To compare the retentive ability and deformation of Acetal resin with Cobalt-Chromium clasps via Insertion Removal apparatus after subjecting them to stimulate clinical use. Materials and Methods Materials used for this study are commercially available Cobalt-Chromium alloy namely Wironit, Bego, Germany and Acetal resin namely Biodentaplast, Bredent, Germany. The test samples were divided into two major groups based on the type of materials used in the study. Each major group is further subdivided into two sub groups based on the retentive undercut depths used to engage the clasps. So a total of 20 specimens were prepared, comprising of 5 specimens in each sub group. Then the specimens were tested for retention force and deformation. Results The results of this study indicate that acetal resin clasps are resistant to deformation and may offer a clinical advantage over the conventional metal clasps. The retentive force of acetal resin clasps did not decrease over the cycling periods. This would be attributed to the resilient nature of acetal resin. Under the conditions of the present study cobalt chromium clasps lost retentive force within 730 cycles of placement and removal and continued to lose retentive force during the remaining test period. Conclusion This invitro study demonstrated that retentive force of cobalt chromium clasp is superior to that of Acetal resin for removable partial dentures. As acetal resin clasps exhibits greater flexibility and long term retentive resiliency, it can be used for removable partial dentures where aesthetics or periodontal health is a primary concern. PMID:26894173

  9. Beneficial Effect of Acetic Acid on the Xylose Utilization and Bacterial Cellulose Production by Gluconacetobacter xylinus.

    PubMed

    Yang, Xiao-Yan; Huang, Chao; Guo, Hai-Jun; Xiong, Lian; Luo, Jun; Wang, Bo; Chen, Xue-Fang; Lin, Xiao-Qing; Chen, Xin-De

    2014-09-01

    In this work, acetic acid was found as one promising substrate to improve xylose utilization by Gluconacetobacter xylinus CH001. Also, with the help of adding acetic acid into medium, the bacterial cellulose (BC) production by G. xylinus was increased significantly. In the medium containing 3 g l(-1) acetic acid, the optimal xylose concentration for BC production was 20 g l(-1). In the medium containing 20 g l(-1) xylose, the xylose utilization and BC production by G. xylinus were stimulated by acetic acid within certain concentration. The highest BC yield (1.35 ± 0.06 g l(-1)) was obtained in the medium containing 20 g l(-1) xylose and 3 g l(-1) acetic acid after 14 days. This value was 6.17-fold higher than the yield (0.21 ± 0.01 g l(-1)) in the medium only containing 20 g l(-1) xylose. The results analyzed by FE-SEM, FTIR, and XRD showed that acetic acid affected little on the microscopic morphology and physicochemical characteristics of BC. Base on the phenomenon observed, lignocellulosic acid hydrolysates (xylose and acetic acid are main carbon sources present in it) could be considered as one potential substrate for BC production.

  10. Medroxyprogesterone acetate exacerbates glutamate excitotoxicity.

    PubMed

    Nilsen, Jon; Morales, Alison; Brinton, Roberta Diaz

    2006-07-01

    We previously demonstrated that progesterone functions as a neuroprotective agent whereas medroxyprogesterone acetate (MPA; Provera) does not. Moreover, MPA antagonized the neuroprotective and neurotrophic outcomes induced by 17beta-estradiol (E2). Towards developing effective hormone therapies for protection against neurodegeneration, we sought to determine whether formulation, chemical features or prevention versus treatment mode of exposure affected the outcome of MPA treatment in survival of primary hippocampal neurons. Results of these analyses indicated that both crystalline MPA and a pharmaceutical formulation (Depo-Provera) lacked neuroprotective efficacy, indicating that the effects were not dependent upon MPA formulation. Likewise, MPA in the prevention and treatment paradigms were equally ineffective at promoting neuronal survival, indicating that timing of MPA administration was not a factor. Further, the detrimental effects of MPA were not due to the presence of the acetate group, as medroxyprogesterone was as ineffective as MPA in promoting neuronal survival. Moreover, MPA pretreatment exacerbated neuron death induced by glutamate excitotoxicity as indicated by a 40% increase in neuron death determined by direct live/dead cell count and a commensurate increase in the number of positive cells by terminal deoxynucleotidyl transferase-mediated nick end-labeling. Collectively these results predict that the progestin formulation of hormone therapy will affect the vulnerability of the central nervous system to degenerative insults.

  11. Development of PMA real-time PCR method to quantify viable cells of Pantoea agglomerans CPA-2, an antagonist to control the major postharvest diseases on oranges.

    PubMed

    Soto-Muñoz, Lourdes; Teixidó, Neus; Usall, Josep; Viñas, Inmaculada; Crespo-Sempere, Ana; Torres, Rosario

    2014-06-16

    Dilution plating is the quantification method commonly used to estimate the population level of postharvest biocontrol agents, but this method does not permit a distinction among introduced and indigenous strains. Recently, molecular techniques based on DNA amplification such as quantitative real-time PCR (qPCR) have been successfully applied for their high strain-specific detection level. However, the ability of qPCR to distinguish viable and nonviable cells is limited. A promising strategy to avoid this issue relies on the use of nucleic acid intercalating dyes, such as propidium monoazide (PMA), as a sample pretreatment prior to the qPCR. The objective of this study was to optimize a protocol based on PMA pre-treatment samples combined with qPCR to distinguish and quantify viable cells of the biocontrol agent P. agglomerans CPA-2 applied as a postharvest treatment on orange. The efficiency of PMA-qPCR method under the established conditions (30μM PMA for 20min of incubation followed by 30min of LED light exposure) was evaluated on an orange matrix. Results showed no difference in CFU or cells counts of viable cells between PMA-qPCR and dilution plating. Samples of orange matrix inoculated with a mixture of viable/dead cells showed 5.59log10 CFU/ml by dilution plating, 8.25log10 cells/ml by qPCR, and 5.93log10 cells/ml by PMA-qPCR. Furthermore, samples inoculated with heat-killed cells were not detected by dilution plating and PMA-qPCR, while by qPCR was of 8.16log10 cells/ml. The difference in quantification cycles (Cq) among qPCR and PMA-qPCR was approximately 16cycles, which means a reduction of 65,536 fold of the dead cells detected. In conclusion, PMA-qPCR method is a suitable tool for quantify viable CPA-2 cells, which could be useful to estimate the ability of this antagonist to colonize the orange surface.

  12. Multiplex PMA-qPCR Assay with Internal Amplification Control for Simultaneous Detection of Viable Legionella pneumophila, Salmonella typhimurium, and Staphylococcus aureus in Environmental Waters.

    PubMed

    Li, Haiyan; Xin, Hongyi; Li, Sam Fong Yau

    2015-12-15

    Pathogenic microorganisms are responsible for many infectious diseases, and pathogen monitoring is important and necessary for water quality control. This study for the first time explored a multiplex quantitative real-time PCR (qPCR) technique combined with propidium monoazide (PMA) to simultaneously detect viable Legionella pneumophila, Salmonella typhimurium, and Staphylococcus aureus in one reaction from water samples. Sodium lauroyl sarcosinate (sarkosyl) was applied to enhance the dead bacterial permeability of PMA. The sensitivity of the multiplex PMA-qPCR assay achieved two colony-forming units (CFU) per reaction for L. pneumophila and three CFU per reaction for S. typhimurium and S. aureus. No PCR products were amplified from all nontarget control samples. Significantly, with comparable specificity and sensitivity, this newly invented multiplex PMA-qPCR assay took a much shorter time than did conventional culture assays when testing water samples with spiked bacteria and simulated environmental water treatment. The viable multiplex PMA-qPCR assay was further successfully applied to pathogen detection from rivers, canals, and tap water samples after simple water pretreatment. PMID:26512952

  13. The involvement of NFAT transcriptional activity suppression in SIRT1-mediated inhibition of COX-2 expression induced by PMA/Ionomycin.

    PubMed

    Jia, Yu-Yan; Lu, Jie; Huang, Yue; Liu, Guang; Gao, Peng; Wan, Yan-Zhen; Zhang, Ran; Zhang, Zhu-Qin; Yang, Rui-Feng; Tang, Xiaoqiang; Xu, Jing; Wang, Xu; Chen, Hou-Zao; Liu, De-Pei

    2014-01-01

    SIRT1, a class III histone deacetylase, acts as a negative regulator for many transcription factors, and plays protective roles in inflammation and atherosclerosis. Transcription factor nuclear factor of activated T cells (NFAT) has been previously shown to play pro-inflammatory roles in endothelial cells. Inhibition of NFAT signaling may be an attractive target to regulate inflammation in atherosclerosis. However, whether NFAT transcriptional activity is suppressed by SIRT1 remains unknown. In this study, we found that SIRT1 suppressed NFAT-mediated transcriptional activity. SIRT1 interacted with NFAT, and the NHR and RHR domains of NFAT mediated the interaction with SIRT1. Moreover, we found that SIRT1 primarily deacetylated NFATc3. Adenoviral over-expression of SIRT1 suppressed PMA and calcium ionophore Ionomycin (PMA/Io)-induced COX-2 expression in human umbilical vein endothelial cells (HUVECs), while SIRT1 RNAi reversed the effects in HUVECs. Moreover, inhibition of COX-2 expression by SIRT1 in PMA/Io-treated HUVECs was largely abrogated by inhibiting NFAT activation. Furthermore, SIRT1 inhibited NFAT-induced COX-2 promoter activity, and reduced NFAT binding to the COX-2 promoter in PMA/Io-treated HUVECs. These results suggest that suppression of NFAT transcriptional activity is involved in SIRT1-mediated inhibition of COX-2 expression induced by PMA/Io, and that the negative regulatory mechanisms of NFAT by SIRT1 may contribute to its anti-inflammatory effects in atherosclerosis.

  14. Cytoplasmic Hsp70 promotes ubiquitination for endoplasmic reticulum-associated degradation of a misfolded mutant of the yeast plasma membrane ATPase, PMA1.

    PubMed

    Han, Sumin; Liu, Yu; Chang, Amy

    2007-09-01

    Cells have a variety of strategies for dealing with misfolded proteins. Heat shock response involves transcriptional induction of chaperones to promote and/or correct folding, and also activation of the ubiquitin/proteasome system to degrade defective proteins. In the secretory pathway, it is primarily luminal misfolded or unassembled proteins that trigger the unfolded protein response which, like heat shock, induces chaperones and components of the endoplasmic reticulum (ER)-associated degradation (ERAD) pathway. To understand cellular response to a misfolded polytopic membrane protein of the secretory pathway, we studied Pma1-D378S, a model ERAD substrate. Expression of misfolded Pma1 induces heat shock response in the absence of increased temperature. Overexpression of HSF1, the transcription factor that mediates heat shock response, increases degradation of Pma1-D378S without temperature upshift. Nevertheless, efficient Pma1-D378S degradation occurs in an hsf1 mutant that maintains basal transcription levels but cannot mediate transcriptional activation. Thus, heat shock protein induction enhances but is not necessary for ERAD. The Ssa group of cytoplasmic Hsp70 chaperones is required for ERAD of both Pma1-D378S and another transmembrane ERAD substrate, Ste6*. In the absence of Ssa chaperones, ubiquitination of both substrates is impaired, resulting in stabilization. We suggest a role for Hsp70 cytoplasmic chaperones in recognition by the endoplasmic reticulum-associated ubiquitination machinery.

  15. Understanding Palladium Acetate from a User Perspective.

    PubMed

    Carole, William A; Colacot, Thomas J

    2016-06-01

    The behavior of palladium acetate is reviewed with respect to its synthesis, characterization, structure (in both solution and solid state), and activation pathways. In addition, comparisons of catalytic activities between pure palladium acetate and two common byproducts, Pd3 (OAc)5 (NO2 ) and polymeric [Pd(OAc)2 ]n , typically present in commercially available material are reviewed. Hence, this minireview serves as a concise guide for the users of palladium acetate from both academia and industry. PMID:27125630

  16. 21 CFR 184.1721 - Sodium acetate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... sodium sulfate and sodium bicarbonate. (b) The ingredient meets the specifications of the Food Chemicals... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium acetate. 184.1721 Section 184.1721 Food and... Substances Affirmed as GRAS § 184.1721 Sodium acetate. (a) Sodium acetate (C2H3O2Na, CAS Reg. No. 127-09-3...

  17. 21 CFR 184.1721 - Sodium acetate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... sodium sulfate and sodium bicarbonate. (b) The ingredient meets the specifications of the Food Chemicals... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Sodium acetate. 184.1721 Section 184.1721 Food and... Substances Affirmed as GRAS § 184.1721 Sodium acetate. (a) Sodium acetate (C2H3O2Na, CAS Reg. No. 127-09-3...

  18. 21 CFR 184.1721 - Sodium acetate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... sodium sulfate and sodium bicarbonate. (b) The ingredient meets the specifications of the Food Chemicals... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Sodium acetate. 184.1721 Section 184.1721 Food and... Substances Affirmed as GRAS § 184.1721 Sodium acetate. (a) Sodium acetate (C2H3O2Na, CAS Reg. No. 127-09-3...

  19. 21 CFR 184.1721 - Sodium acetate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... sodium sulfate and sodium bicarbonate. (b) The ingredient meets the specifications of the Food Chemicals... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Sodium acetate. 184.1721 Section 184.1721 Food and... Substances Affirmed as GRAS § 184.1721 Sodium acetate. (a) Sodium acetate (C2H3O2Na, CAS Reg. No. 127-09-3...

  20. Survival and persistence of fecal host-specific Bacteroidales cells and their DNA assessed by PMA-qPCR

    NASA Astrophysics Data System (ADS)

    Bae, S.; Bombardelli, F.; Wuertz, S.

    2008-12-01

    Understanding and managing microbial pollutions in water is one of the foremost challenges of establishing effective managements and remediation strategies to impaired water bodies polluted by uncharacterized fecal sources. Quantitative microbial source tracking (MST) approaches using fecal Bacteroidales and quantitative PCR (qPCR) assays to measure gene copies of host-specific 16S rRNA genetic markers are promising because they can allow for identifying and quantifying fecal loadings from a particular animal host and understanding the fate and transport of host-specific Bacteroidales over a range of conditions in water bodies. Similar to the case of traditional fecal indicator bacteria, a relatively long persistence of target DNA may hamper applied MST studies, if genetic markers cannot be linked to recent fecal pollution in water. We report a successful approach to removing the qPCR signal derived from free DNA and dead host-specific Bacteroidales cells by selectively binding the DNA and consequently inhibiting PCR amplification using light- activated propidium monoazide (PMA). Optimal PMA-qPCR conditions were determined as 100 µM of PMA concentration and a 10-min light exposure time at different solids concentrations in order to mimic a range of water samples. Under these conditions, PMA-qPCR resulted in the selective exclusion of DNA from heat- treated cells of non-culturable Bacteroidales in human feces and wastewater influent and effluent samples. Also, the persistence of feces-derived host-specific Bacteroidales DNA and their cells (determined by universal, human-, cow- and dog-specific Bacteroidales qPCR assays) in seawater was investigated in microcosms at environmental conditions. The average T99 (two log reduction) value for host-specific viable Bacteroidales cells was 28 h, whereas that for total host-specific Bacteroidales DNA was 177 h. Natural sunlight did not have a strong influence on the fate of fecal Bacteroidales cells and their DNA, presumably

  1. Positron scattering from vinyl acetate

    NASA Astrophysics Data System (ADS)

    Chiari, L.; Zecca, A.; Blanco, F.; García, G.; Brunger, M. J.

    2014-09-01

    Using a Beer-Lambert attenuation approach, we report measured total cross sections (TCSs) for positron scattering from vinyl acetate (C4H6O2) in the incident positron energy range 0.15-50 eV. In addition, we also report an independent atom model with screening corrected additivity rule computation results for the TCSs, differential and integral elastic cross sections, the positronium formation cross section and inelastic integral cross sections. The energy range of these calculations is 1-1000 eV. While there is a reasonable qualitative correspondence between measurement and calculation for the TCSs, in terms of the energy dependence of those cross sections, the theory was found to be a factor of ˜2 larger in magnitude at the lower energies, even after the measured data were corrected for the forward angle scattering effect.

  2. Extractive fermentation of acetic acid

    SciTech Connect

    Busche, R.M.

    1991-12-31

    In this technoeconomic evaluation of the manufacture of acetic acid by fermentation, the use of the bacterium: Acetobacter suboxydans from the old vinegar process was compared with expected performance of the newer Clostridium thermoaceticum bacterium. Both systems were projected to operate as immobilized cells in a continuous, fluidized bed bioreactor, using solvent extraction to recover the product. Acetobacter metabolizes ethanol aerobically to produce acid at 100 g/L in a low pH medium. This ensures that the product is in the form of a concentrated extractable free acid, rather than as an unextractable salt. Unfortunately, yields from glucose by way of the ethanol fermentation are poor, but near the biological limits of the organisms involved. Conversely, C. thermoaceticum is a thermophilic anaerobe that operates at high fermentation rates on glucose at neutral pH to produce acetate salts directly in substantially quantitative yields. However, it is severely inhibited by product, which restricts concentration to a dilute 20 g/L. An improved Acetobacter system operating with recycled cells at 50 g/L appears capable of producing acid at $0.38/lb, as compared with a $0.29/lb price for synthetic acid. However, this system has only a limited margin for process improvement. The present Clostridium system cannot compete, since the required selling price would be $0.42/lb. However, if the organism could be adapted to tolerate higher product concentrations at acid pH, selling price could be reduced to $0.22/lb, or about 80% of the price of synthetic acid.

  3. Aurantiamide acetate suppresses the growth of malignant gliomas in vitro and in vivo by inhibiting autophagic flux

    PubMed Central

    Yang, Yi; Zhang, Li-hui; Yang, Bing-xian; Tian, Jin-kui; Zhang, Lin

    2015-01-01

    We aim to investigate the effect of aurantiamide acetate isolated from the aerial parts of Clematis terniflora DC against gliomas. Human malignant glioma U87 and U251 cells were incubated with different concentrations (0–100 μM) of aurantiamide acetate. Aurantiamide acetate greatly decreased the cell viability in a dose- and time-dependent manner. It induced moderate mitochondrial fragmentation and the loss of mitochondrial membrane potential. No significant difference was found in the alternation of other intracellular organelles, although F-actin structure was slightly disturbed. Apparent ultrastructure alternation with increased autophagosome and autolysosome accumulation was observed in aurantiamide acetate-treated cells. The expression of LC3-II was greatly up-regulated in cells exposed to aurantiamide acetate (P < 0.05 compared with control). The cytoplasmic accumulation of autophagosomes and autolysosomes induced by aurantiamide acetate treatment was confirmed by fluorescent reporter protein labelling. Administration of chloroquine (CQ), which inhibits the fusion step of autophagosomes, further increased the accumulation of autophagosomes in the cytoplasm of U87 cells. Autophagy inhibition by 3-methyladenine, Bafilomycin A1 or CQ had no influence on aurantiamide acetate-induced cytotoxicity, whereas autophagy stimulator rapamycin significantly suppressed aurantiamide acetate-induced cell death. The anti-tumour effects of aurantiamide acetate were further evaluated in tumour-bearing nude mice. Intratumoural injection of aurantiamide acetate obviously suppressed tumour growth, and increased number of autophagic vacuoles was observed in tumour tissues of animals receiving aurantiamide acetate. Our findings suggest that aurantiamide acetate may suppress the growth of malignant gliomas by blocking autophagic flux. PMID:25704599

  4. 21 CFR 882.5820 - Implanted cerebellar stimulator.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... premarket approval application (PMA) or notice of completion of a product development protocol (PDP) is required. A PMA or notice of completion of a PDP is required to be filed with the Food and Drug..., 1976 shall have an approved PMA or declared completed PDP in effect before beginning...

  5. 21 CFR 882.5820 - Implanted cerebellar stimulator.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... premarket approval application (PMA) or notice of completion of a product development protocol (PDP) is required. A PMA or notice of completion of a PDP is required to be filed with the Food and Drug..., 1976 shall have an approved PMA or declared completed PDP in effect before beginning...

  6. Oxidation of indole-3-acetic acid to oxindole-3-acetic acid by etiolated and green corn tissues

    SciTech Connect

    Reinecke, D. )

    1989-04-01

    Etiolated corn tissues oxidase indole-3-acetic acid (IAA) to oxindole-3-acetic acid (OxIAA). This oxidation results in loss of auxin activity and may plant a role in regulating IAA-stimulated growth. The enzyme has been partially purified and characterized and shown to require O{sub 2}, and a heat-stable lipid-soluble corn factor which can be replaced by linolenic or linoleic acids in the oxidation of IAA. Corn oil was tested as a cofactor in the IAA oxidation reaction. Corn oil stimulated enzyme activity by 30% while trilinolein was inactive. The capacity of green tissue to oxidize IAA was examined by incubating leaf sections from 2 week old light-grown corn seedlings with {sup 14}C-IAA. OxIAA and IAA were separated from other IAA metabolites on a 3 ml anion exchange column. Of the IAA taken up by the sections, 13% was oxidized to OxIAA. This is the first evidence that green tissue of corn may also regulate IAA levels by oxidizing IAA to OxIAA.

  7. Subject bibliography of the PMA205 (Program Manager Air 205) Network Technical Library at Oak Ridge National Laboratory

    SciTech Connect

    Ayers, M.V.

    1990-05-01

    The PMA205 (Program Manager Air 205) Network Technical Library at the Oak Ridge National Laboratory (ORNL) contains documents relating to US Department of Defense standards for computer-based training technology and training and American National Standards Institute international standards for user interfaces and Computer-Aided Acquisition and Logistic Support. The collection emphasizes supporting research in instructional system design, software engineering, user system interfaces, human factors engineering, and cognitive psychology as it differentiates between higher and lower cognitive tasking. The collection currently consists of about 670 documents of various types. These include military standards and specifications, reports, conference proceedings, dissertations, technical manuals, books, journal articles, and military instructions and directives. The documents have been added to the library as the result of literature searches and personal submission from team members. It is a selective collection and not a comprehensive one. A database, written in Procite/PC, contains the cataloged holdings of the library. Each record contains the bibliographic information and an abstract. The database provides access to information in the records by either full text searches using Boolean logic or individual field searching. One-word quick searches'' can be performed on the date, title, or author fields. The browsing capability for retrieved items is by full record or brief format. Search results can be read from the screen, printed to hard copy, or transferred to a disk file for later use. Disks containing the database and printed bibliographies are available to PMA205 network team members upon request.

  8. Transient overexpression of catalase does not inhibit TNF- or PMA-induced NF-kappa B activation.

    PubMed

    Suzuki, Y J; Mizuno, M; Packer, L

    1995-05-16

    H2O2 has been proposed as a second messenger involved in cell signaling for NF-kappa B activation. In the present study, this hypothesis was tested by transiently overexpressing catalase, a specific scavenger of H2O2, in COS-1 cells. A mammalian expression vector was constructed by incorporating catalase gene from pCAT10 clone into the unique EcoRI site of the pSG5 vector which contains the SV-40 promoter. Transient transfection of the catalase expression vector by the DEAE-dextran method led to a four-fold increase in catalase activity and catalase content as detected by immunoblot analysis. This level of increase was detected in both nuclear/mitochondrial- and cytosolic/microsomal fractions. Overexpression of catalase, however, did not block TNF- or PMA-induced NF-kappa B activation. These results weaken the hypothesis that H2O2 is a second messenger for TNF- and PMA-signaling for NF-kappa B activation.

  9. Manufacturing Ethyl Acetate From Fermentation Ethanol

    NASA Technical Reports Server (NTRS)

    Rohatgi, Naresh K.; Ingham, John D.

    1991-01-01

    Conceptual process uses dilute product of fermentation instead of concentrated ethanol. Low-concentration ethanol, extracted by vacuum from fermentation tank, and acetic acid constitutes feedstock for catalytic reaction. Product of reaction goes through steps that increases ethyl acetate content to 93 percent by weight. To conserve energy, heat exchangers recycle waste heat to preheat process streams at various points.

  10. Comparison of Acetate Turnover in Methanogenic and Sulfate-Reducing Sediments by Radiolabeling and Stable Isotope Labeling and by Use of Specific Inhibitors: Evidence for Isotopic Exchange

    PubMed Central

    de Graaf, W.; Wellsbury, P.; Parkes, R. J.; Cappenberg, T. E.

    1996-01-01

    Acetate turnover in the methanogenic freshwater anoxic sediments of Lake Vechten, The Netherlands, and in anoxic sediments from the Tamar Estuary, United Kingdom, and the Grosser Jasmunder Bodden, Germany, the latter two dominated by sulfate reduction, was determined. Stable isotopes and radioisotopes, inhibitors (chloroform and fluoroacetate), and methane flux were used to provide independent estimates of acetate turnover. Pore water acetate pool sizes were determined by gas chromatography with a flame ionization detector, and stable isotope-labeled acetate was determined by gas chromatography-mass spectrometry. The appearance of acetates with a different isotope labeling pattern from that initially added demonstrated that isotopic exchange occurred during methanogenic acetate metabolism. The predominant exchange processes were (i) D-H exchange in the methyl group and (ii) (sup13)C-(sup12)C exchange at the carboxyl carbon. These exchanges are most probably caused by the activity of the enzyme complex carbon monoxide dehydrogenase and subsequent methyl group dehydrogenation by tetrahydromethanopterine or a related enzyme. The methyl carbon was not subject to exchange during transformation to methane, and hence acetate with the methyl carbon labeled will provide the most reliable estimate of acetate turnover to methane. Acetate turnover rate estimates with these labels were consistent with independent estimates of acetate turnover (acetate accumulation after inhibition and methane flux). Turnover rates from either radioisotope- or stable isotope-labeled methyl carbon isotopes are, however, dependent on accurate determination of the acetate pool size. The additions of large amounts of stable isotope-labeled acetate elevate the acetate pool size, stimulating acetate consumption and causing deviation from steady-state kinetics. This can, however, be overcome by the application of a non-steady-state model. Isotopic exchange in sediments dominated by sulfate reduction

  11. Acute effects of ethanol and acetate on glucose kinetics in normal subjects

    SciTech Connect

    Yki-Jaervinen, H.; Koivisto, V.A.; Ylikahri, R.; Taskinen, M.R. )

    1988-02-01

    The authors compared the effects of two ethanol doses on glucose kinetics and assessed the role of acetate as a mediator of ethanol-induced insulin resistance. Ten normal males were studied on four occasions, during which either a low or moderate ethanol, acetate, or saline dose was administered. Both ethanol doses similarly inhibited basal glucose production. The decrease in R{sub a} was matched by a comparable decrease in glucose utilization (R{sub d}), resulting in maintenance of normoglycemia. During hyperinsulinemia glucose disposal was lower in the moderate than the low-dose ethanol or saline studies. During acetate infusion, the blood acetate level was comparable with those in the ethanol studies. Acetate had no effect on glucose kinetics. In conclusion, (1) in overnight fasted subjects, ethanol does not cause hypoglycemia because its inhibitory effect on R{sub a} is counterbalanced by equal inhibition of R{sub d}; (2) basal R{sub a} and R{sub d} are maximally inhibited already by small ethanol doses, whereas inhibition of insulin-stimulated glucose disposal requires a moderate ethanol dose; and (3) acetate is not the mediator of ethanol-induced insulin resistance.

  12. Acetate mediates a microbiome-brain-β-cell axis to promote metabolic syndrome.

    PubMed

    Perry, Rachel J; Peng, Liang; Barry, Natasha A; Cline, Gary W; Zhang, Dongyan; Cardone, Rebecca L; Petersen, Kitt Falk; Kibbey, Richard G; Goodman, Andrew L; Shulman, Gerald I

    2016-06-01

    Obesity, insulin resistance and the metabolic syndrome are associated with changes to the gut microbiota; however, the mechanism by which modifications to the gut microbiota might lead to these conditions is unknown. Here we show that increased production of acetate by an altered gut microbiota in rodents leads to activation of the parasympathetic nervous system, which, in turn, promotes increased glucose-stimulated insulin secretion, increased ghrelin secretion, hyperphagia, obesity and related sequelae. Together, these findings identify increased acetate production resulting from a nutrient-gut microbiota interaction and subsequent parasympathetic activation as possible therapeutic targets for obesity. PMID:27279214

  13. Cytotoxicity and DNA-protein crosslink formation in rat nasal tissues exposed to vinyl acetate are carboxylesterase-mediated.

    PubMed

    Kuykendall, J R; Taylor, M L; Bogdanffy, M S

    1993-12-01

    Vinyl acetate is used in the paint, adhesive, and paper board industries. Vinyl acetate is a nasal carcinogen in rats exposed by inhalation for 2 years to 200 and 600 ppm, but not 50 ppm. Previous studies from our laboratory suggest that rat liver microsome-activated vinyl acetate induces plasmid DNA-histone crosslinks, in vitro, through esterase-mediated metabolism. Since nasal tissues contain high levels of carboxylesterase, tumorigenesis may be related to in situ production of the hydrolysis products acetaldehyde and acetic acid. Vinyl acetate was cytotoxic to both respiratory and olfactory tissues in vitro at 50-200 mM, but not 25 mM, after 2 hr exposure. Pretreatment of rats with the carboxylesterase inhibitor, bis-(p-nitrophenyl) phosphate (BNPP), attenuated the cytotoxic effects and metabolism of vinyl acetate in both tissue types. Semicarbazide, an aldehyde scavenger, was unable to protect the tissues from vinyl acetate-induced cytotoxicity. When the metabolites were tested, acetic acid, but not acetaldehyde, was cytotoxic to both tissues. The induction of DNA-protein crosslink (DPXL) formation by acetaldehyde and vinyl acetate in rat nasal epithelial tissues was detected using a sodium dodecyl sulfate/KCl precipitation technique. Endogenous crosslink levels ranged from 0.5 to 2.0% of total DNA and were considered background. Epithelial cells isolated from both olfactory and respiratory turbinates exhibited dose- and time-dependent increases in DPXL formation when exposed to 10-150 mM acetaldehyde for 1-2 hr at 37 degrees C. Similarly, respiratory and olfactory epithelial cells exposed to 5-75 mM vinyl acetate for 1-2 hr accumulated up to 12- and 15-fold higher crosslink levels than untreated cells, respectively. However, vinyl acetate appears to induce much higher levels of DPXLs at equimolar doses than acetaldehyde. This is thought to be related to stimulation of acetaldehyde-induced DPXL formation by the pH lowering effect of acetic acid production (via

  14. Application of acetate buffer in pH adjustment of sorghum mash and its influence on fuel ethanol fermentation.

    PubMed

    Zhao, Renyong; Bean, Scott R; Crozier-Dodson, Beth Ann; Fung, Daniel Y C; Wang, Donghai

    2009-01-01

    A 2 M sodium acetate buffer at pH 4.2 was tried to simplify the step of pH adjustment in a laboratory dry-grind procedure. Ethanol yields or conversion efficiencies of 18 sorghum hybrids improved significantly with 2.0-5.9% (3.9% on average) of relative increases when the method of pH adjustment changed from traditional HCl to the acetate buffer. Ethanol yields obtained using the two methods were highly correlated (R (2) = 0.96, P < 0.0001), indicating that the acetate buffer did not influence resolution of the procedure to differentiate sorghum hybrids varying in fermentation quality. Acetate retarded the growth of Saccharomyces cerevisiae, but did not affect the overall fermentation rate. With 41-47 mM of undissociated acetic acid in mash of a sorghum hybrid at pH 4.7, rates of glucose consumption and ethanol production were inhibited during exponential phase but promoted during stationary phase. The maximum growth rate constants (mu(max)) were 0.42 and 0.32 h(-1) for cells grown in mashes with pH adjusted by HCl and the acetate buffer, respectively. Viable cell counts of yeast in mashes with pH adjusted by the acetate buffer were 36% lower than those in mashes adjusted by HCl during stationary phase. Coupled to a 5.3% relative increase in ethanol, a 43.6% relative decrease in glycerol was observed, when the acetate buffer was substituted for HCl. Acetate helped to transfer glucose to ethanol more efficiently. The strain tested did not use acetic acid as carbon source. It was suggested that decreased levels of ATP under acetate stress stimulate glycolysis to ethanol formation, increasing its yield at the expense of biomass and glycerol production.

  15. High rates of [1-14C]acetate incorporation into the lipid of isolated spinach chloroplasts.

    PubMed Central

    Roughan, P G; Slack, C R; Holland, R

    1976-01-01

    Spinach chloroplasts, isolated by techniques yielding preparations with high O2- evolving activity, showed rates of light-dependent acetate incorporation into lipids 3-4 fold higher than any previously reported. Incorporation rates as high as 500 nmol of acetate/h per mg of chlorophyll were measured in buffered sorbitol solutions containing only NaHCO3 and [1-14C]acetate, and as high as 800 nmol/h per mg of chlorophyll when 0.13 mM-Triton X-100 was also included in the reaction media. The fatty acids synthesized were predominantly oleic (70-80% of the total fatty acid radioactivity) and palmitic (20-25%) with only minor amounts (1-5%) of linoleic acid. Linolenic acid synthesis was not detected in the system in vitro. Free fatty acids accounted for 70-90% of the radioactivity incorporated and the remainder was shared fairly evenly between 1,2-diacylglycerols and polar lipids. Oleic acid constituted 80-90% of the free fatty acids synthesized, but the diacylglycerols and polar lipids contained slightly more palmitic acid than oleic acid. Triton X-100 stimulated the synthesis of diacylglycerols 3-6 fold, but stimulated free fatty acid synthesis only 1-1.5-fold. Added glycerol 1-phosphate stimulated both the synthesis of diacylglycerols and palmitic acid relative to oleic acid, but did not increase acetate incorporation into total chloroplast lipids. CoA and ATP, when added separately, stimulated acetate incorporation into chloroplast lipids to variable extents and had no effect on the types of lipid synthesized, but when added together resulted in 34% of the incorporated acetate appearing in long-chain acyl-CoA. Pyruvate was a much less effective precursor of chloroplast fatty acids than was acetate. PMID:985452

  16. Inhibitory effects of [6]-gingerol on PMA-induced COX-2 expression and activation of NF-kappaB and p38 MAPK in mouse skin.

    PubMed

    Kim, Sue Ok; Chun, Kyung-Soo; Kundu, Joydeb Kumar; Surh, Young-Joon

    2004-01-01

    [6]-Gingerol, a major pungent ingredient of ginger (Zingiber officinale Roscoe, Zingiberaceae), has a wide array of pharmacologic effects. Previous studies have demonstrated that [6]-gingerol inhibits mouse skin tumor promotion and anchorage-independent growth of cultured mouse epidermal cells stimulated with epidermal growth factor. Cyclooxygenase-2 (COX-2), a key enzyme in the prostaglandin biosynthesis, has been recognized as a molecular target for many anti-inflammatory as well as chemopreventive agents. Topical application of [6]-gingerol inhibited phorbol 12-myristate 13-acetate -induced COX-2 expression. One of the essential transcription factors responsible for COX-2 induction is NF-kappaB. [6]-Gingerol suppressed NF-kappaB DNA binding activity in mouse skin. In addition, [6]-gingerol inhibited the phoshorylation of p38 mitogen-activated protein kinase which may account for its inactivation of NF-kappaB and suppression of COX-2 expression. PMID:15630166

  17. Conversion to eslicarbazepine acetate monotherapy

    PubMed Central

    French, Jacqueline; Jacobson, Mercedes P.; Pazdera, Ladislav; Gough, Mallory; Cheng, Hailong; Grinnell, Todd; Blum, David

    2016-01-01

    Objective: To assess the efficacy and safety of eslicarbazepine acetate (ESL) monotherapy. Methods: This post hoc pooled analysis of 2 randomized double-blind studies (093-045 and -046) included adults with partial-onset seizures medically uncontrolled by 1 or 2 antiepileptic drugs (AEDs). Following the baseline period (8 weeks), eligible patients were randomized 2:1 to receive ESL 1,600 mg or 1,200 mg once daily for 18 weeks; the primary endpoint was study exit by meeting predefined exit criteria (signifying worsening seizure control). In each study, treatment was considered effective if the upper 95% confidence limit for exit rate was lower than the historical control threshold (65.3%). Results: Pooled exit rates were as follows: ESL 1,600 mg = 20.6% (95% confidence interval: 15.6%–26.8%); ESL 1,200 mg = 30.8% (23.0%–40.5%). Use of 2 baseline AEDs or rescue medication, US location, epilepsy duration ≥20 years, and higher maximum baseline seizure frequency were associated with higher exit risks. Median percent reductions in standardized seizure frequency between baseline and the 18-week double-blind period were as follows: ESL 1,600 mg = 43.2%; ESL 1,200 mg = 35.7%; baseline carbamazepine use was associated with smaller reductions. Safety profiles were similar between ESL doses. Conclusions: Exit rates for ESL monotherapy (1,600 mg and 1,200 mg once daily) were lower than the historical control threshold, irrespective of baseline AED use and region, with no additional safety concerns identified. Clinical factors and location clearly influence treatment responses in conversion-to-monotherapy trials. Classification of evidence: This pooled analysis provides Class IV evidence that for adults with medically uncontrolled partial-onset seizures, ESL monotherapy is well tolerated and effective. PMID:26911639

  18. Intravitreal injection of octreotide acetate.

    PubMed

    Robertson, J E; Westra, I; Woltering, E A; Winthrop, K L; Barrie, R; O'Dorisio, T M; Holmes, D

    1997-04-01

    This study was conducted to determine the feasibility of injecting the somatostatin analogue, octreotide acetate (OA), into the vitreous cavity. Previous work suggests that octreotide effectively inhibits angiogenesis in vitro, thus its use in vivo may slow the progression of proliferative eye disease. Fifty micrograms of aqueous OA in 50 microliters aqueous solution was injected into the mid-vitreous of kitten eyes (n = 6), and OA levels were monitored over 4 days. A long-acting release form of octreotide (OA-LAR) was also injected into the mid-vitreous of rabbit eyes at doses of 0.36 (n = 16), 1.1 (n = 1), 2.1 (n = 1), 4.05 (n = 1), 8.2 (n = 1), and 36 mg (n = 3) in solution; and octreotide concentrations were measured at various time points over 42 days. OA concentrations were determined by a highly specific radioimmunoassay. Aqueous octreotide was eliminated rapidly (t1/2 = 16 hours) from the vitreous of the kitten eye, with only negligible amounts recoverable 4 days post-injection. In the long-acting form, OA in the rabbit eye reached peak levels at 28 days. By 42 days, OA levels had declined to the 14-day level. Doses of OA-LAR of 1.1 mg or less produced no gross evidence of clinical toxicity and elicited no grossly visible ocular side effects. Doses greater than 1.1 mg produced significant toxicity, including cataracts and rubeosis. The 28-day peak release for long-acting OA implies that monthly intravitreal injections could provide continual high levels of OA. Intravitreal injection of long-acting OA provides sustained, high concentrations of drug, and deserves further study as a potential treatment of proliferative eye diseases.

  19. Germination and adhesion of fungal conidia on polycarbonate membranes and on apple fruit exposed to mycoactive acetate esters.

    PubMed

    Filonow, Alexander B

    2003-02-01

    The adhesion and germination of conidia of nine fungal species were assessed on polycarbonate membranes or on the skin of apple fruit in sealed glass bottles injected or not injected with acetate esters. Adhesion was determined after dislodging conidia from surfaces using a sonication probe. Adhesion and germination of conidia of Aspergillus flavus, Aspergillus fumigatus, Aspergillus niger, Penicillium citrinum, Penicillium claviforme, or Trichoderma sp. on membranes after 48 h were not increased in a 1.84 microg mL(-1) headspace of butyl acetate (BA), ethyl acetate, hexyl acetate, 2-methylbutyl acetate, pentyl acetate, or propyl acetate. Adhesion and germination of Botrytis cinerea, Penicillium expansum, and Penicillium roquefortii conidia were stimulated by all esters. Only conidia of B. cinerea and P. expansum exhibited increased adhesion and germination on the skin of apple fruit in bottles exposed to 0.92 microg mL(-1) of BA. Only conidia of B. cinerea and P. expansum produced decay in inoculated puncture wounds on fruit. Freshly made puncture wounds or 24-h-old puncture wounds in fruit were more adhesive than the unpunctured skin of fruit to conidia of B. cinerea or P. expansum. Fresh wounds were more adhesive to both fungi than 24-h-old puncture wounds. The skin and wounds of fruit were as adhesive to B. cinerea conidia as they were to P. expansum conidia. A 4-h exposure to 1.43 microg mL(-1) of BA increased adhesion of B. cinerea and P. expansum conidia in 24-h-old wounds. Results suggest that acetate-ester stimulation most likely is not a rare phenomenon in the fungi. For nutrient-dependent decay pathogens of apple fruit, acetate esters may be an alternative chemical cue used to maintain adhesion of conidia to wound surfaces. PMID:12718401

  20. PMA-SiO2 catalyzed synthesis of indolo[2,3-c]quinolines as potent anti cancer agents.

    PubMed

    Srihari, P; Padmabhavani, B; Ramesh, S; Bharath Kumar, Y; Singh, Ashita; Ummanni, R

    2015-06-01

    PMA-SiO2 catalyzed Pictet-Spengler reaction of aryl amine linked to C-3 of the indole and the aryl aldehydes was achieved. In the series of the synthesized compounds, 6b, 10b and 12b were found to be cytotoxic against prostate, lung, breast and cervical cancer cell lines selectively with no significant effect on the growth of the control fibroblast cell line NIH3T3. Further determining their cytotoxic potential we found that 10b and 12b show cell cycle arrest in DU145 prostate cancer cells indicating a role in cell cycle progression. Both the molecules showed effect on decreased phosphorylation of NF-κB on serine 536 residue which is strongly implicated in many different types of cancers. Taken together, the series of indoloquinolines elicit potent anti-cancer potential providing a mean for developing novel indoloquinoline based anti-cancer agents. PMID:25933593

  1. Fragrance material review on 3-phenylpropyl acetate.

    PubMed

    McGinty, D; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of 3-phenylpropyl acetate when used as a fragrance ingredient is presented. 3-Phenylpropyl acetate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1-4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for 3-phenylpropyl acetate were evaluated, then summarized, and includes: physical properties, acute toxicity, skin irritation, skin sensitization, and toxicokinetics data. A safety assessment of the entire AAASAE will be published simultaneously with this document. Please refer to Belsito et al., 2012 for an overall assessment of the safe use of this material and all AAASAE in fragrances.

  2. Fragrance material review on anisyl acetate.

    PubMed

    McGinty, D; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of anisyl acetate when used as a fragrance ingredient is presented. Anisyl acetate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1-4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for anisyl acetate were evaluated, then summarized, and includes: physical properties, skin irritation, skin sensitization, elicitation, and phototoxicity data. A safety assessment of the entire AAASAE will be published simultaneously with this document. Please refer to Belsito et al., 2012 for an overall assessment of the safe use of this material and all AAASAE in fragrances.

  3. Fragrance material review on piperonyl acetate.

    PubMed

    McGinty, D; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of piperonyl acetate when used as a fragrance ingredient is presented. Piperonyl acetate is a member of the fragrance structural group aryl alkyl alcohol simple acid esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1-4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for piperonyl acetate were evaluated, then summarized, and includes: physical properties, acute toxicity, skin irritation, mucous membrane (eye) irritation, skin sensitization, toxicokinetics, and genotoxicity data. A safety assessment of the entire AAASAE will be published simultaneously with this document. Please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all AAASAE in fragrances.

  4. Fragrance material review on 2-phenylpropyl acetate.

    PubMed

    McGinty, D; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of 2-phenylpropyl acetate when used as a fragrance ingredient is presented. 2-Phenylpropyl acetate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1-4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for 2-phenylpropyl acetate were evaluated, then summarized, and includes: physical properties, acute toxicity, skin irritation, mucous membrane (eye) irritation, and skin sensitization data. A safety assessment of the entire AAASAE will be published simultaneously with this document. Please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all AAASAE in fragrances.

  5. Fragrance material review on 4-methylbenzyl acetate.

    PubMed

    McGinty, D; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of 4-methylbenzyl acetate when used as a fragrance ingredient is presented. 4-Methylbenzyl acetate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1-4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for 4-methylbenzyl acetate were evaluated, then summarized, and includes: physical properties, skin irritation, skin sensitization, and elicitation data. A safety assessment of the entire AAASAE will be published simultaneously with this document. Please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all AAASAE in fragrances.

  6. Acetate limitation and nitrite accumulation during denitrification

    SciTech Connect

    Oh, J.; Silverstein, J.

    1999-03-01

    Nitrite accumulated in denitrifying activated sludge mixed liquor when the carbon and electron source, acetate, was limited. If acetate was added to obtain a carbon-to-nitrogen (C:N) ratio in the range of 2:1 to 3:1, nitrate was completely consumed at the same rate with no nitrite accumulation, indicating that nitrate concentration controlled the respiration rate as long as sufficient substrate was present. However, when acetate was reduced to a C:N ratio of 1:1, while nitrate continued to be consumed, > 50% of the initial nitrate-nitrogen accumulated as nitrite and 29% persisted as nitrite throughout an endogenous denitrification period of 8--9 h. While nitrite accumulated during acetate-limited denitrification, the specific nitrate reduction rate increased significantly compared with the rate when excess acetate was provided as follows: 0.034 mg-NO{sub 3}-N/mg-mixed liquid volatile suspended solids/h versus 0.023 mg-NO{sub 3}-N/mg-mixed liquid volatile suspended solids/h, respective. This may be explained by nitrate respiration out-competing nitrite respiration for limited acetate electrons. Complete restoration of balanced denitrification and elimination of nitrite accumulation during denitrification required several weeks after the C:N ratio was increased back to 2:1.

  7. Response of anaerobes to methyl fluoride, 2-bromoethanesulfonate and hydrogen during acetate degradation.

    PubMed

    Hao, Liping; Lü, Fan; Li, Lei; Shao, Liming; He, Pinjing

    2013-05-01

    To use the selective inhibition method for quantitative analysis of acetate metabolism in methanogenic systems, the responses of microbial communities and metabolic activities, which were involved in anaerobic degradation of acetate, to the addition of methyl fluoride (CH3F), 2-bromoethanesulfonate (BES) and hydrogen were investigated in a thermophilic batch experiment. Both the methanogenic inhibitors, i.e., CH3F and BES, showed their effectiveness on inhibiting CH4 production, whereas acetate metabolism other than acetoclastic methanogenesis was stimulated by BES, as reflected by the fluctuated acetate concentration. Syntrophic acetate oxidation was thermodynamically blocked by hydrogen (H2), while H2-utilizing reactions as hydrogenotrophic methanogenesis and homoacetogenesis were correspondingly promoted. Results of PCR-DGGE fingerprinting showed that, CH3F did not influence the microbial populations significantly. However, the BES and hydrogen notably altered the bacterial community structures and increased the diversity. BES gradually changed the methanogenic community structure by affecting the existence of different populations to different levels, whilst H2 greatly changed the abundance of different methanogenic populations, and induced growth of new species.

  8. MrpA functions in energy conversion during acetate-dependent growth of Methanosarcina acetivorans.

    PubMed

    Jasso-Chávez, Ricardo; Apolinario, Ethel E; Sowers, Kevin R; Ferry, James G

    2013-09-01

    The role of the multisubunit sodium/proton antiporter (Mrp) of Methanosarcina acetivorans was investigated with a mutant deleted for the gene encoding the MrpA subunit. Antiporter activity was 5-fold greater in acetate-grown versus methanol-grown wild-type cells, consistent with the previously published relative levels of mrp transcript. The rate, final optical density, and dry weight/methane ratio decreased for the mutant versus wild type when cultured with a growth-limiting concentration of acetate. All growth parameters of the mutant or wild type were identical when grown with methanol in medium containing a growth-limiting Na(+) concentration of 1.04 M. The lag phase, growth rate, and final optical density for growth of the mutant were suboptimal compared to the wild type when cultured with acetate in medium containing either 0.54 or 1.04 M Na(+). The addition of 25 mM NaCl to resting cell suspensions stimulated ATP synthesis driven by a potassium diffusion potential. ATP synthesis was greater in wild-type than mutant cells grown with acetate, a trend that held for methanol-grown cells, albeit less pronounced. Both sodium and proton ionophores reduced ATP synthesis in the wild type grown with either substrate. The results indicated that the Mrp complex is essential for efficient ATP synthesis and optimal growth at the low concentrations of acetate encountered in the environment.

  9. Phase Preference by Active, Acetate-Utilizing Bacteria at the Rifle, CO Integrated Field Research Challenge Site

    SciTech Connect

    Kerkhof, L.; Williams, K.H.; Long, P.E.; McGuinness, L.

    2011-02-21

    Previous experiments at the Rifle, Colorado Integrated Field Research Challenge (IFRC) site demonstrated that field-scale addition of acetate to groundwater reduced the ambient soluble uranium concentration. In this report, sediment samples collected before and after acetate field addition were used to assess the active microbes via {sup 13}C acetate stable isotope probing on 3 phases [coarse sand, fines (8-approximately 150 {micro}m), groundwater (0.2-8 {micro}m)] over a 24-day time frame. TRFLP results generally indicated a stronger signal in {sup 13}C-DNA in the 'fines' fraction compared to the sand and groundwater. Before the field-scale acetate addition, a Geobacter-like group primarily synthesized {sup 13}C-DNA in the groundwater phase, an alpha Proteobacterium primarily grew on the fines/sands, and an Acinetobacter sp. and Decholoromonas-like OTU utilized much of the {sup 13}C acetate in both groundwater and particle-associated phases. At the termination of the field-scale acetate addition, the Geobacter-like species was active on the solid phases rather than the groundwater, while the other bacterial groups had very reduced newly synthesized DNA signal. These findings will help to delineate the acetate utilization patterns of bacteria in the field and can lead to improved methods for stimulating distinct microbial populations in situ.

  10. Quantitative detection of viable helminth ova from raw wastewater, human feces, and environmental soil samples using novel PMA-qPCR methods.

    PubMed

    Gyawali, P; Ahmed, W; Sidhu, J P S; Nery, S V; Clements, A C; Traub, R; McCarthy, J S; Llewellyn, S; Jagals, P; Toze, S

    2016-09-01

    In this study, we have evaluated the efficacy of propidium monoazide quantitative polymerase chain reaction (PMA-qPCR) to differentiate between viable and non-viable Ancylostoma caninum ova. The newly developed method was validated using raw wastewater seeded with known numbers of A. caninum ova. Results of this study confirmed that PMA-qPCR has resulted in average of 88 % reduction (P < 0.05) in gene copy numbers for 50 % viable +50 % non-viable when compared with 100 % viable ova. A reduction of 100 % in gene copies was observed for 100 % non-viable ova when compared with 100 % viable ova. Similar reductions (79-80 %) in gene copies were observed for A. caninum ova-seeded raw wastewater samples (n = 18) collected from wastewater treatment plants (WWTPs) A and B. The newly developed PMA-qPCR method was applied to determine the viable ova of different helminths (A. caninum, A. duodenale, Necator americanus and Ascaris lumbricoides) in raw wastewater, human fecal and soil samples. None of the unseeded wastewater samples were positive for the above-mentioned helminths. N. americanus and A. lumbricoides ova were found in unseeded human fecal and soil samples. For the unseeded human fecal samples (1 g), an average gene copy concentration obtained from qPCR and PMA-qPCR was found to be similar (6.8 × 10(5) ± 6.4 × 10(5) and 6.3 × 10(5) ± 4.7 × 10(5)) indicating the presence of viable N. americanus ova. Among the 24 unseeded soil samples tested, only one was positive for A. lumbricoides. The mean gene copy concentration in the positively identified soil sample was 1.0 × 10(5) ± 1.5 × 10(4) (determined by qPCR) compared to 4.9 × 10(4) ± 3.7 × 10(3) (determined by PMA-qPCR). The newly developed PMA-qPCR methods were able to detect viable helminth ova from wastewater and soil samples and could be adapted for health risk assessment. PMID:27306209

  11. Quantitative detection of viable helminth ova from raw wastewater, human feces, and environmental soil samples using novel PMA-qPCR methods.

    PubMed

    Gyawali, P; Ahmed, W; Sidhu, J P S; Nery, S V; Clements, A C; Traub, R; McCarthy, J S; Llewellyn, S; Jagals, P; Toze, S

    2016-09-01

    In this study, we have evaluated the efficacy of propidium monoazide quantitative polymerase chain reaction (PMA-qPCR) to differentiate between viable and non-viable Ancylostoma caninum ova. The newly developed method was validated using raw wastewater seeded with known numbers of A. caninum ova. Results of this study confirmed that PMA-qPCR has resulted in average of 88 % reduction (P < 0.05) in gene copy numbers for 50 % viable +50 % non-viable when compared with 100 % viable ova. A reduction of 100 % in gene copies was observed for 100 % non-viable ova when compared with 100 % viable ova. Similar reductions (79-80 %) in gene copies were observed for A. caninum ova-seeded raw wastewater samples (n = 18) collected from wastewater treatment plants (WWTPs) A and B. The newly developed PMA-qPCR method was applied to determine the viable ova of different helminths (A. caninum, A. duodenale, Necator americanus and Ascaris lumbricoides) in raw wastewater, human fecal and soil samples. None of the unseeded wastewater samples were positive for the above-mentioned helminths. N. americanus and A. lumbricoides ova were found in unseeded human fecal and soil samples. For the unseeded human fecal samples (1 g), an average gene copy concentration obtained from qPCR and PMA-qPCR was found to be similar (6.8 × 10(5) ± 6.4 × 10(5) and 6.3 × 10(5) ± 4.7 × 10(5)) indicating the presence of viable N. americanus ova. Among the 24 unseeded soil samples tested, only one was positive for A. lumbricoides. The mean gene copy concentration in the positively identified soil sample was 1.0 × 10(5) ± 1.5 × 10(4) (determined by qPCR) compared to 4.9 × 10(4) ± 3.7 × 10(3) (determined by PMA-qPCR). The newly developed PMA-qPCR methods were able to detect viable helminth ova from wastewater and soil samples and could be adapted for health risk assessment.

  12. Acetic acid production from food wastes using yeast and acetic acid bacteria micro-aerobic fermentation.

    PubMed

    Li, Yang; He, Dongwei; Niu, Dongjie; Zhao, Youcai

    2015-05-01

    In this study, yeast and acetic acid bacteria strains were adopted to enhance the ethanol-type fermentation resulting to a volatile fatty acids yield of 30.22 g/L, and improve acetic acid production to 25.88 g/L, with food wastes as substrate. In contrast, only 12.81 g/L acetic acid can be obtained in the absence of strains. The parameters such as pH, oxidation reduction potential and volatile fatty acids were tested and the microbial diversity of different strains and activity of hydrolytic ferment were investigated to reveal the mechanism. The optimum pH and oxidation reduction potential for the acetic acid production were determined to be at 3.0-3.5 and -500 mV, respectively. Yeast can convert organic matters into ethanol, which is used by acetic acid bacteria to convert the organic wastes into acetic acid. The acetic acid thus obtained from food wastes micro-aerobic fermentation liquid could be extracted by distillation to get high-pure acetic acid.

  13. Acetylation of Starch with Vinyl Acetate in Imidazolium Ionic Liquids and Characterization of Acetate Distribution

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Starch was acetylated with vinyl acetate in different 1-butyl-3-methylimidazolium (BMIM) salts as solvent in effort to produce starches with different acetylation patterns. Overall degree of substitution was much higher for basic anions such as acetate and dicyanimide (dca) than for neutral anions ...

  14. 40 CFR 721.10001 - 2-Ethoxyethanol, 2-ethoxyethanol acetate, 2-methoxyethanol, and 2-methoxyethanol acetate.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... new uses subject to reporting. (1) The chemical substances identified as 2-ethoxyethanol (CAS No. 110-80-5), 2-ethoxyethanol acetate (CAS No. 111-15-9), 2-methoxyethanol (CAS No. 109-86-4), and 2-methoxyethanol acetate (CAS No. 110-49-6) are subject to reporting under this section for the significant new...

  15. 40 CFR 721.10001 - 2-Ethoxyethanol, 2-ethoxyethanol acetate, 2-methoxyethanol, and 2-methoxyethanol acetate.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... new uses subject to reporting. (1) The chemical substances identified as 2-ethoxyethanol (CAS No. 110-80-5), 2-ethoxyethanol acetate (CAS No. 111-15-9), 2-methoxyethanol (CAS No. 109-86-4), and 2-methoxyethanol acetate (CAS No. 110-49-6) are subject to reporting under this section for the significant new...

  16. Tested Demonstrations: Buffer Capacity of Various Acetic Acid-Sodium Acetate Systems: A Lecture Experiment.

    ERIC Educational Resources Information Center

    Donahue, Craig J.; Panek, Mary G.

    1985-01-01

    Background information and procedures are provided for a lecture experiment which uses indicators to illustrate the concept of differing buffer capacities by titrating acetic acid/sodium acetate buffers with 1.0 molar hydrochloric acid and 1.0 molar sodium hydroxide. A table with data used to plot the titration curve is included. (JN)

  17. Dynamic Protonation Equilibrium of Solvated Acetic Acid

    SciTech Connect

    Gu, Wei; Frigato, Tomaso; Straatsma, TP; Helms, Volkhard H.

    2007-04-13

    For the first time, the dynamic protonation equilibrium between an amino acid side chain analogue and bulk water as well as the diffusion properties of the excess proton were successfully reproduced through unbiased computer simulations. During a 50 ns Q-HOP MD simulation, two different regimes of proton transfer were observed. Extended phases of frequent proton swapping between acetic acid and nearby water were separated by phases where the proton freely diffuses in the simulation box until it is captured again by acetic acid. The pKa of acetic acid was calculated around 3.0 based on the relative population of protonated and deprotonated states and the diffusion coefficient of excess proton was computed from the average mean squared displacement in the simulation. Both calculated values agree well with the experimental measurements.

  18. Leuprolide acetate-induced generalized papular eruption.

    PubMed

    Burris, Katy; Ding, Catherine Y; Lim, Geoffrey F S

    2014-06-01

    Leuprolide acetate, a gonadotropin-releasing hormone agonist, is used in the treatment of prostate cancer. We report a unique case of a disseminated papular rash following leuprolide acetate injections in a 65-year-old man that shares clinical and histopathological features of papuloerythroderma of Ofuji. Leuprolide-induced papuloerythroderma, as well as a limited number of other disseminated cutaneous eruptions caused by this drug, is extremely rare, with only one case previously reported. Our case calls attention to this uncommon side effect in a commonly used hormonal therapy.

  19. Trypanosomatidae produce acetate via a mitochondrial acetate:succinate CoA transferase.

    PubMed

    Van Hellemond, J J; Opperdoes, F R; Tielens, A G

    1998-03-17

    Hydrogenosome-containing anaerobic protists, such as the trichomonads, produce large amounts of acetate by an acetate:succinate CoA transferase (ASCT)/succinyl CoA synthetase cycle. The notion that mitochondria and hydrogenosomes may have originated from the same alpha-proteobacterial endosymbiont has led us to look for the presence of a similar metabolic pathway in trypanosomatids because these are the earliest-branching mitochondriate eukaryotes and because they also are known to produce acetate. The mechanism of acetate production in these organisms, however, has remained unknown. Four different members of the trypanosomatid family: promastigotes of Leishmania mexicana mexicana, L. infantum and Phytomonas sp., and procyclics of Trypanosoma brucei were analyzed as well as the parasitic helminth Fasciola hepatica. They all use a mitochondrial ASCT for the production of acetate from acetyl CoA. The succinyl CoA that is produced during acetate formation by ASCT is recycled presumably to succinate by a mitochondrial succinyl CoA synthetase, concomitantly producing ATP from ADP. The ASCT of L. mexicana mexicana promastigotes was further characterized after partial purification of the enzyme. It has a high affinity for acetyl CoA (Km 0.26 mM) and a low affinity for succinate (Km 6.9 mM), which shows that significant acetate production can occur only when high mitochondrial succinate concentrations prevail. This study identifies a metabolic pathway common to mitochondria and hydrogenosomes, which strongly supports a common origin for these two organelles.

  20. Process for the preparation of vinyl acetate

    DOEpatents

    Tustin, G.C.; Zoeller, J.R.; Depew, L.S.

    1998-02-17

    This invention pertains to the preparation of vinyl acetate by contacting within a contact zone a mixture of ketene and acetaldehyde with an acid catalyst at about one bar pressure and between about 85 and 200 C and removing the reaction products from the contact zone.

  1. Process for the preparation of vinyl acetate

    DOEpatents

    Tustin, Gerald Charles; Zoeller, Joseph Robert; Depew, Leslie Sharon

    1998-01-01

    This invention pertains to the preparation of vinyl acetate by contacting within a contact zone a mixture of ketene and acetaldehyde with an acid catalyst at about one bar pressure and between about 85.degree. and 200.degree. C. and removing the reaction products from the contact zone.

  2. Heat Bonding of Irradiated Ethylene Vinyl Acetate

    NASA Technical Reports Server (NTRS)

    Slack, D. H.

    1986-01-01

    Reliable method now available for joining parts of this difficult-tobond material. Heating fixture encircles ethylene vinyl acetate multiplesocket part, providing heat to it and to tubes inserted in it. Fixtures specially designed to match parts to be bonded. Tube-and-socket bonds made with this technique subjected to tensile tests. Bond strengths of 50 percent that of base material obtained consistently.

  3. Fragrance material review on phenethyl acetate.

    PubMed

    McGinty, D; Vitale, D; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of phenethyl acetate when used as a fragrance ingredient is presented. Phenethyl acetate is a member of the fragrance structural group aryl alkyl alcohol simple acid esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1-4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for phenethyl acetate were evaluated, then summarized, and includes: physical properties, acute toxicity, skin irritation, mucous membrane (eye) irritation, skin sensitization, elicitation, toxicokinetics, repeated dose, genotoxicity, and carcinogenicity data. A safety assessment of the entire AAASAE will be published simultaneously with this document. Please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all AAASAE in fragrances.

  4. Fragrance material review on benzyl acetate.

    PubMed

    McGinty, D; Vitale, D; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of benzyl acetate when used as a fragrance ingredient is presented. Benzyl acetate is a member of the fragrance structural group aryl alkyl alcohol simple acid esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1-4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for benzyl acetate were evaluated, then summarized, and includes: physical properties, acute toxicity, skin irritation, mucous membrane (eye) irritation, skin sensitization, elicitation, phototoxicity, toxicokinetics, repeated dose, reproductive toxicity, genotoxicity, or carcinogenicity data. A safety assessment of the entire AAASAE will be published simultaneously with this document. Refer Belsito et al. (2012) for an overall assessment of the safe use of this material and all AAASAE in fragrances.

  5. Advanced Colloids Experiment (ACE-T1)

    NASA Technical Reports Server (NTRS)

    Meyer, William V.; Sicker, Ron; Brown, Dan; Eustace, John

    2015-01-01

    Increment 45 - 46 Science Symposium presentation of Advanced Colloids Experiment (ACE-T1) to RPO. The purpose of this event is for Principal Investigators to present their science objectives, testing approach, and measurement methods to agency scientists, managers, and other investigators.

  6. Corrosion of stainless steel during acetate production

    SciTech Connect

    Qi, J.S.; Lester, G.C.

    1996-07-01

    Corrosion of types 304, 304L, 316, and 316L stainless steel (SS) during the esterification of acetic acid and alcohol or glycol ether was investigated. The catalyst for this reaction, sulfuric acid or para-toluene sulfonic acid (PTSA), was shown to cause more corrosion on reactor equipment than CH{sub 3}COOH under the process conditions commonly practiced in industry. The corrosive action of the catalyst occurred only in the presence of water. Thus, for the batch processes, corrosion occurred mostly during the initial stage of esterification, where water produced by the reaction created an aqueous environment. After water was distilled off, the corrosion rate declined to a negligible value. The corrosion inhibitor copper sulfate, often used in industrial acetate processes, was found to work well for a low-temperature process (< 95 C) such as in production of butyl acetate, but it accelerated corrosion in the glycol ether acetate processes where temperatures were > 108 C. Process conditions that imparted low corrosion rates were determined.

  7. Cellulose Acetate Membranes: Electron Microscopy of Structure.

    PubMed

    Riley, R; Gardner, J O; Merten, U

    1964-02-21

    Electron photomicrographs of cellulose acetate membranes used in the reverse osmosis processof water desalination reveal a dense surface layer with a porous substructure. The high rate oftransmission for water can be correlated with the thickness of the dense layer on the air-driedsurface of the membrane.

  8. Synthesis of Cellulose Acetate from Cotton Byproducts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cotton burr and cottonseed hull are relatively inexpensive cotton byproducts. In an effort to derive greater value out of these natural renewable materials, we have succeeded in converting part of them into cellulose acetate without prior chemical breakdown or physical separation of cellulose, ligni...

  9. Effect of nitrate, acetate, and hydrogen on native perchlorate-reducing microbial communities and their activity in vadose soil.

    PubMed

    Nozawa-Inoue, Mamie; Jien, Mercy; Yang, Kun; Rolston, Dennis E; Hristova, Krassimira R; Scow, Kate M

    2011-05-01

    The effect of nitrate, acetate, and hydrogen on native perchlorate-reducing bacteria (PRB) was examined by conducting microcosm tests using vadose soil collected from a perchlorate-contaminated site. The rate of perchlorate reduction was enhanced by hydrogen amendment and inhibited by acetate amendment, compared with unamendment. Nitrate was reduced before perchlorate in all amendments. In hydrogen-amended and unamended soils, nitrate delayed perchlorate reduction, suggesting that the PRB preferentially use nitrate as an electron acceptor. In contrast, nitrate eliminated the inhibitory effect of acetate amendment on perchlorate reduction and increased the rate and the extent, possibly because the preceding nitrate reduction/denitrification decreased the acetate concentration that was inhibitory to the native PRB. In hydrogen-amended and unamended soils, perchlorate reductase gene (pcrA) copies, representing PRB densities, increased with either perchlorate or nitrate reduction, suggesting that either perchlorate or nitrate stimulates the growth of the PRB. In contrast, in acetate-amended soil pcrA increased only when perchlorate was depleted: a large portion of the PRB may have not utilized nitrate in this amendment. Nitrate addition did not alter the distribution of the dominant pcrA clones in hydrogen-amended soil, likely because of the functional redundancy of PRB as nitrate-reducers/denitrifiers, whereas acetate selected different pcrA clones from those with hydrogen amendment.

  10. Effect of nitrate, acetate and hydrogen on native perchlorate-reducing microbial communities and their activity in vadose soil

    PubMed Central

    Nozawa-Inoue, Mamie; Jien, Mercy; Yang, Kun; Rolston, Dennis E.; Hristova, Krassimira R.; Scow, Kate M.

    2011-01-01

    Effect of nitrate, acetate and hydrogen on native perchlorate-reducing bacteria (PRB) was examined by conducting microcosm tests using vadose soil collected from a perchlorate-contaminated site. The rate of perchlorate reduction was enhanced by hydrogen amendment and inhibited by acetate amendment, compared to unamendment. Nitrate was reduced before perchlorate in all amendments. In hydrogen-amended and unamended soils, nitrate delayed perchlorate reduction, suggesting the PRB preferentially use nitrate as an electron acceptor. In contrast, nitrate eliminated the inhibitory effect of acetate amendment on perchlorate reduction and increased the rate and the extent, possibly because the preceding nitrate reduction/denitrification decreased the acetate concentration which was inhibitory to the native PRB. In hydrogen-amended and unamended soils, perchlorate reductase gene (pcrA) copies, representing PRB densities, increased with either perchlorate or nitrate reduction, suggesting either perchlorate or nitrate stimulates growth of the PRB. In contrast, in acetate-amended soil pcrA increased only when perchlorate was depleted: a large portion of the PRB may have not utilized nitrate in this amendment. Nitrate addition did not alter the distribution of the dominant pcrA clones in hydrogen-amended soil, likely because of the functional redundancy of PRB as nitrate-reducers/denitrifiers, whereas acetate selected different pcrA clones from those with hydrogen amendment. PMID:21284679

  11. Phenyl Acetate Preparation from Phenol and Acetic Acid: Reassessment of a Common Textbook Misconception.

    ERIC Educational Resources Information Center

    Hocking, M. B.

    1980-01-01

    Reassesses a common textbook misconception that "...phenols cannot be esterified directly." Results of experiments are discussed and data tables provided of an effective method for the direct preparation of phenyl acetate. (CS)

  12. The microwave spectrum of n-hexyl acetate and structural aspects of n-alkyl acetates

    NASA Astrophysics Data System (ADS)

    Attig, T.; Kannengießer, R.; Kleiner, I.; Stahl, W.

    2014-04-01

    The microwave spectrum of n-hexyl acetate was recorded in the range of 10-13.5 GHz using the Aachen MB-FTMW spectrometer. The rotational constants of the most abundant conformer were determined to be A = 3.3591100(32) GHz, B = 0.39596553(53) GHz, and C = 0.36999804(31) GHz. Quantum chemical calculations for specific conformers were carried out at the MP2/6-311++G(d,p) level. The programs XIAM and BELGI were used to analyze the internal rotation of the acetyl methyl group. The observed conformer of n-hexyl acetate was compared to the lowest energy conformers of n-butyl acetate and n-pentyl acetate.

  13. Effect of octreotide acetate on pancreatic exocrine and endocrine functions after pancreatoduodenal resection.

    PubMed

    Petrin, P; Antoniutti, M; Zaramella, D; Da Lio, C; Basso, D; Plebani, M; Panozzo, M P; Costantino, V; Pedrazzoli, S

    1995-01-01

    In view of forecasting the effect of octreotide acetate (Sandostatin) in preventing fistula formation after pancreatic surgery, 9 patients, who had pancreatoduodenectomy 8-12 days before, underwent a 2-day study. The first day, by means of a catheter located in the jejunal loop separately anastomosed to the pancreatic remnant, basal and after secretin stimulation pancreatic secretion was evaluated. During the 2nd day the possible inhibitory effect of octreotide on basal and stimulated secretion was investigated. Under the experimental conditions of the study Sandostatin showed little effect on the water and bicarbonate increase as stimulated by secretin. A greater hormone inhibitory effect on amylase production and pancreatic endocrine function was seen. On the basis of these results the use of Sandostatin can hardly be seen as useful in preventing fistula formation after pancreatic resection.

  14. Small molecule glutaminase inhibitors block glutamate release from stimulated microglia.

    PubMed

    Thomas, Ajit G; O'Driscoll, Cliona M; Bressler, Joseph; Kaufmann, Walter; Rojas, Camilo J; Slusher, Barbara S

    2014-01-01

    Glutaminase plays a critical role in the generation of glutamate, a key excitatory neurotransmitter in the CNS. Excess glutamate release from activated macrophages and microglia correlates with upregulated glutaminase suggesting a pathogenic role for glutaminase. Both glutaminase siRNA and small molecule inhibitors have been shown to decrease excess glutamate and provide neuroprotection in multiple models of disease, including HIV-associated dementia (HAD), multiple sclerosis and ischemia. Consequently, inhibition of glutaminase could be of interest for treatment of these diseases. Bis-2-(5-phenylacetimido-1,2,4-thiadiazol-2-yl)ethyl sulfide (BPTES) and 6-diazo-5-oxo-l-norleucine (DON), two most commonly used glutaminase inhibitors, are either poorly soluble or non-specific. Recently, several new BPTES analogs with improved physicochemical properties were reported. To evaluate these new inhibitors, we established a cell-based microglial activation assay measuring glutamate release. Microglia-mediated glutamate levels were significantly augmented by tumor necrosis factor (TNF)-α, phorbol 12-myristate 13-acetate (PMA) and Toll-like receptor (TLR) ligands coincident with increased glutaminase activity. While several potent glutaminase inhibitors abrogated the increase in glutamate, a structurally related analog devoid of glutaminase activity was unable to block the increase. In the absence of glutamine, glutamate levels were significantly attenuated. These data suggest that the in vitro microglia assay may be a useful tool in developing glutaminase inhibitors of therapeutic interest. PMID:24269238

  15. Effect of cyproterone acetate on pituitary-adrenocortical function in man.

    PubMed

    van Wayjen, R G; van den Ende, A

    1981-01-01

    Recent literature (1973-1976) suggests suppression of pituitary-adrenal function in patients (eg with pubertas praecox) who are treated with cyproterone acetate in high doses for prolonged periods. Therefore we investigated in our metabolic ward the effects of administration of 200 mg cyproterone acetate per day during 20 days to 4 healthy male volunteers. Baseline plasma cortisol and ACTH levels, repeated diurnal plasma cortisol and ACTH profiles and the results of tetracosactide (Synacthen) stimulation tests and single-dose metyrapone (Metopiron) tests proved to be comparable before, during and after treatment. Moreover, a slight gradual increase in urinary cortisol excretion during the observation period indicated that cyproterone acetate in the given dose during 20 days certainly does not reduce the pituitary-adrenal function of 4 healthy male volunteers. Long-term administration (during 1 to 7 years) of the combination of cyproterone acetate and ethinyloestradiol did not suppress serum levels of cortisol, prolactin, thyroxine and TSH in 18 female patients with hirsutism and/or acne. PMID:6257015

  16. Stimulation of neutrophils by tumor necrosis factor

    SciTech Connect

    Klebanoff, S.J.; Vadas, M.A.; Harlan, J.M.; Sparks, L.H.; Gamble, J.R.; Agosti, J.M.; Waltersdorph, A.M.

    1986-06-01

    Human recombinant tumor necrosis factor (TNF) was shown to be a weak direct stimulus of the neutrophil respiratory burst and degranulation. The stimulation, as measured by iodination, H/sub 2/O/sub 2/ production, and lysozyme release, was considerably increased by the presence of unopsonized zymosan in the reaction mixture, an effect which was associated with the increased ingestion of the zymosan. TNF does not act as an opsonin but, rather, reacts with the neutrophil to increase its phagocytic activity. TNF-dependent phagocytosis, as measured indirectly by iodination, is inhibited by monoclonal antibodies (Mab) 60.1 and 60.3, which recognize different epitopes on the C3bi receptor/adherence-promoting surface glycoprotein of neutrophils. Other neutrophil stimulants, namely N-formyl-methionyl-leucyl-phenylalanine, the Ca2+ ionophore A23187, and phorbol myristic acetate, also increase iodination in the presence of zymosan; as with TNF, the effect of these stimulants is inhibited by Mab 60.1 and 60.3, whereas, in contrast to that of TNF, their stimulation of iodination is unaffected by an Mab directed against TNF. TNF may be a natural stimulant of neutrophils which promotes adherence to endothelial cells and to particles, leading to increased phagocytosis, respiratory burst activity, and degranulation.

  17. Viscometric study of chitosan solutions in acetic acid/sodium acetate and acetic acid/sodium chloride.

    PubMed

    Costa, Cristiane N; Teixeira, Viviane G; Delpech, Marcia C; Souza, Josefa Virginia S; Costa, Marcos A S

    2015-11-20

    A viscometric study was carried out at 25°C to assess the physical-chemical behavior in solution and the mean viscometric molar mass (M¯v) of chitosan solutions with different deacetylation degrees, in two solvent mixtures: medium 1-acetic acid 0.3mol/L and sodium acetate 0.2mol/L; and medium 2-acetic acid 0.1mol/L and sodium chloride 0.2mol/L. Different equations were employed, by graphical extrapolation, to calculate the intrinsic viscosities [η] and the viscometric constants, to reveal the solvent's quality: Huggins (H), Kraemer (K) and Schulz-Blaschke (SB). For single-point determination, the equations used were SB, Solomon-Ciuta (SC) and Deb-Chanterjee (DC), resulting in a faster form of analysis. The values of ̄M¯v were calculated by applying the equation of Mark-Houwink-Sakurada. The SB and SC equations were most suitable for single-point determination of [η] and ̄M¯v and the Schulz-Blachke constant (kSB), equal to 0.28, already utilized for various systems, can also be employed to analyze chitosan solutions under the conditions studied.

  18. 21 CFR 582.5892 - a-Tocopherol acetate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or Dietary Supplements 1 § 582.5892 a-Tocopherol acetate. (a) Product. a-Tocopherol acetate. (b) Conditions of use....

  19. 21 CFR 582.5892 - a-Tocopherol acetate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or Dietary Supplements 1 § 582.5892 a-Tocopherol acetate. (a) Product. a-Tocopherol acetate. (b) Conditions of use....

  20. 21 CFR 582.5892 - a-Tocopherol acetate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or Dietary Supplements 1 § 582.5892 a-Tocopherol acetate. (a) Product. a-Tocopherol acetate. (b) Conditions of use....

  1. Separating acetic acid from furol (furfural) by electrodialysis method

    SciTech Connect

    Guan, S.F.; Li, C.S. Ye, S.T.; Shen, S.Y.; Wang, Y.T.; Yu, S.H.

    1981-01-01

    Furfural production by hydrolysis of fibrous plant materials is accompanied by formation of acetic acid in amounts depending on the material used. The amount of acetic formed in the hydrolysis of the fruit shell of oil-tea camellia (Camellia oleosa) (an oilseed-bearing tree) is equal to the amount of furfural. The acetic acid can be separated from the furfural and concentrated to 10% by electrodialysis. A smaller amount of furfural is separated with acetic acid.

  2. Gold-catalyzed cyclization of allenyl acetal derivatives

    PubMed Central

    Vasu, Dhananjayan; Pawar, Samir Kundlik

    2013-01-01

    Summary The gold-catalyzed transformation of allenyl acetals into 5-alkylidenecyclopent-2-en-1-ones is described. The outcome of our deuterium labeling experiments supports a 1,4-hydride shift of the resulting allyl cationic intermediates because a complete deuterium transfer is observed. We tested the reaction on various acetal substrates bearing a propargyl acetate, giving 4-methoxy-5-alkylidenecyclopent-2-en-1-ones 4 via a degradation of the acetate group at the allyl cation intermediate. PMID:24062838

  3. Cyproterone acetate in treatment of precocious puberty.

    PubMed Central

    Kauli, R; Pertzelan, A; Prager-Lewin, R; Grünebaum, M; Laron, Z

    1976-01-01

    Twenty-nine children (23 girls, 6 boys) with precocious puberty were treated with cyproterone acetate for various periods of time ranging from 6 months to 3 years 4 months. They received an oral dose ranging from 70-150 mg/m2 per day, or an intramuscular depot injection once a fortnight or once a month at a dose ranging from 107-230 mg/m2. Both forms of therapy were found to suppress the signs of sexual maturation, but the oral form proved to be superior. Only the younger patients with a bone age under 11 years showed a beneficial effect upon linear growth and bone maturation. No side effects were noted, but additional advantageous effects upon behaviour and sociability were. It is concluded that at present cyproterone acetate by mouth is the drug of choice in the treatment of precocious puberty. The treatment should be initiated as early as possible to attain maximum benefit. PMID:952553

  4. 21 CFR 182.8892 - α-Tocopherol acetate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false α-Tocopherol acetate. 182.8892 Section 182.8892 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD...-Tocopherol acetate. (a) Product. α-Tocopherol acetate. (b) Conditions of use. This substance is...

  5. Kinetics of Ethyl Acetate Synthesis Catalyzed by Acidic Resins

    ERIC Educational Resources Information Center

    Antunes, Bruno M.; Cardoso, Simao P.; Silva, Carlos M.; Portugal, Ines

    2011-01-01

    A low-cost experiment to carry out the second-order reversible reaction of acetic acid esterification with ethanol to produce ethyl acetate is presented to illustrate concepts of kinetics and reactor modeling. The reaction is performed in a batch reactor, and the acetic acid concentration is measured by acid-base titration versus time. The…

  6. 21 CFR 182.8892 - α-Tocopherol acetate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true α-Tocopherol acetate. 182.8892 Section 182.8892 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD...-Tocopherol acetate. (a) Product. α-Tocopherol acetate. (b) Conditions of use. This substance is...

  7. 21 CFR 182.8892 - α-Tocopherol acetate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false α-Tocopherol acetate. 182.8892 Section 182.8892 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD...-Tocopherol acetate. (a) Product. α-Tocopherol acetate. (b) Conditions of use. This substance is...

  8. 21 CFR 582.5892 - a-Tocopherol acetate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false a-Tocopherol acetate. 582.5892 Section 582.5892 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5892 a-Tocopherol acetate. (a) Product. a-Tocopherol acetate. (b) Conditions of use....

  9. 21 CFR 582.5892 - a-Tocopherol acetate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false a-Tocopherol acetate. 582.5892 Section 582.5892 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5892 a-Tocopherol acetate. (a) Product. a-Tocopherol acetate. (b) Conditions of use....

  10. 21 CFR 182.8892 - α-Tocopherol acetate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false α-Tocopherol acetate. 182.8892 Section 182.8892...) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8892 α-Tocopherol acetate. (a) Product. α-Tocopherol acetate. (b) Conditions of use. This substance is generally recognized as safe when used in...

  11. Acetate concentrations and oxidation in salt marsh sediments

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Acetate concentrations and rates of acetate oxidation and sulfate reduction were measured in S. alterniflora sediments in New Hampshire and Massachusetts. Pore water extracted from cores by squeezing or centrifugation contained in greater than 0.1 mM acetate and, in some instances, greater than 1.0 mM. Pore water sampled nondestructively contained much less acetate, often less than 0.01 mM. Acetate was associated with roots, and concentrations varied with changes in plant physiology. Acetate turnover was very low whether whole core or slurry incubations were used. Radiotracers injected directly into soils yielded rates of sulfate reduction and acetate oxidation not significantly different from core incubation techniques. Regardless of incubation method, acetate oxidation did not account for a substantial percentage of sulfate reduction. These results differ markedly from data for unvegetated coastal sediments where acetate levels are low, oxidation rate constants are high, and acetate oxication rates greatly exceed rates of sulfate reduction. The discrepancy between rates of acetate oxidation and sulfate reduction in these marsh soils may be due either to the utilization of substrates other than acetate by sulfate reducers or artifacts associated with measurements of organic utilization by rhizosphere bacteria. Care must be taken when interpreting data from salt marsh sediments since the release of material from roots during coring may affect the concentrations of certain compounds as well as influencing results obtained when sediment incubations are employed.

  12. 21 CFR 584.200 - Ethyl alcohol containing ethyl acetate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Ethyl alcohol containing ethyl acetate. The feed additive ethyl alcohol containing ethyl acetate meets the requirement of 27 CFR 21.62, being not less than 92.5 percent ethyl alcohol, each 100 gallons... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Ethyl alcohol containing ethyl acetate....

  13. 21 CFR 584.200 - Ethyl alcohol containing ethyl acetate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Ethyl alcohol containing ethyl acetate. The feed additive ethyl alcohol containing ethyl acetate meets the requirement of 27 CFR 21.62, being not less than 92.5 percent ethyl alcohol, each 100 gallons... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Ethyl alcohol containing ethyl acetate....

  14. 21 CFR 584.200 - Ethyl alcohol containing ethyl acetate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Ethyl alcohol containing ethyl acetate. The feed additive ethyl alcohol containing ethyl acetate meets the requirement of 27 CFR 21.62, being not less than 92.5 percent ethyl alcohol, each 100 gallons... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Ethyl alcohol containing ethyl acetate....

  15. 21 CFR 584.200 - Ethyl alcohol containing ethyl acetate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Ethyl alcohol containing ethyl acetate. The feed additive ethyl alcohol containing ethyl acetate meets the requirement of 27 CFR 21.62, being not less than 92.5 percent ethyl alcohol, each 100 gallons... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ethyl alcohol containing ethyl acetate....

  16. 21 CFR 584.200 - Ethyl alcohol containing ethyl acetate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Ethyl alcohol containing ethyl acetate. The feed additive ethyl alcohol containing ethyl acetate meets the requirement of 27 CFR 21.62, being not less than 92.5 percent ethyl alcohol, each 100 gallons... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Ethyl alcohol containing ethyl acetate....

  17. 21 CFR 582.5933 - Vitamin A acetate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Vitamin A acetate. 582.5933 Section 582.5933 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5933 Vitamin A acetate. (a) Product. Vitamin A acetate. (b) Conditions of use....

  18. 21 CFR 582.5933 - Vitamin A acetate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Vitamin A acetate. 582.5933 Section 582.5933 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5933 Vitamin A acetate. (a) Product. Vitamin A acetate. (b) Conditions of use....

  19. 21 CFR 582.5933 - Vitamin A acetate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Vitamin A acetate. 582.5933 Section 582.5933 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5933 Vitamin A acetate. (a) Product. Vitamin A acetate. (b) Conditions of use....

  20. 21 CFR 582.5933 - Vitamin A acetate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Vitamin A acetate. 582.5933 Section 582.5933 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5933 Vitamin A acetate. (a) Product. Vitamin A acetate. (b) Conditions of use....

  1. 21 CFR 582.5933 - Vitamin A acetate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Vitamin A acetate. 582.5933 Section 582.5933 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5933 Vitamin A acetate. (a) Product. Vitamin A acetate. (b) Conditions of use....

  2. Calcium magnesium acetate production and cost reduction

    SciTech Connect

    Leuschner, A.P.

    1988-02-01

    The New York State Energy Research and Development Authority (Energy Authority), Consolidated Edison Company of New York, Inc. (ConEd), the New York State Department of Transportation (NYSDOT), the New York State Thruway Authority (NYSTA), Chevron Chemical Company, the National Corn Growers Association (NCGA), and the Massachusetts Department of Public Works (MDPW) sponsored a research program to develop technology capable of producing Calcium Magnesium Acetate (CMA), an alternative road deicer, at a quality and cost which will allow its increased use. The objectives of this program were to determine the feasibility of: (1) producing CMA from regionally available waste and low grade organic feedstocks via biochemical engineering technologies; (2) operating the fermentation at concentrated product levels to reduce energy requirements and minimize drying process costs; (3) using this production approach to produce an environmentally acceptable CMA product; and (4) using and adapting an existing facility for a CMA commercial demonstration plant. The experimental program included:(1) selection of microorganisms for their ability to grow in the absence of sodium chloride and to tolerate high concentrations of calcium, magnesium, and acetate ions; (2) analysis of waste feedstocks for their potential conversion to acetate; (3) analysis of waste organic material for impurities in CMA that could carry over into the environment; (4) batch experiments to determine pH tolerance, growth in the absence of sodium chloride (NaCl), tolerance to magnesium, calcium and acetate ions, effect of substrate concentration, acid distribution, and acid production; and (5) semi-continuous laboratory scale anaerobic digestion experiments to determine loading rates, conversion efficiencies, and other design data. 67 refs., 33 figs., 66 tabs.

  3. Use of PMA1 as a housekeeping biomarker for assessment of toxicant-induced stress in Saccharomyces cerevisiae.

    PubMed

    Schmitt, Marcel; Schwanewilm, Petra; Ludwig, Jost; Lichtenberg-Fraté, Hella

    2006-02-01

    The brewer's yeast Saccharomyces cerevisiae has emerged as a versatile and robust model system for laboratory use to study toxic effects of various substances. In this study, toxicant-induced stresses of pure compounds were investigated in Saccharomyces cerevisiae utilizing a destabilized version of the green fluorescent protein optimized for expression in yeast (yEGFP3) under control of the promoter of the housekeeping plasma membrane ATPase gene PMA1. The responses of the biomarker upon increasing test compound concentrations were monitored by determining the decrease in fluorescence. The reporter assay deployed a simple and robust protocol for the rapid detection of toxic effects within a 96-well microplate format. Fluorescence emissions were normalized to cell growth determined by absorption and were correlated to internal reference standards. The results were expressed as effective concentrations (EC20). Dose-response experiments were conducted in which yeast cells were exposed in minimal medium and in the presence of 20% fetal calf serum to sublethal concentrations of an array of heavy metals, salt, and a number of stress-inducing compounds (Diclofenac, Lindane, methyl-N-nitro-N-nitrosoguanidine [MNNG], hydroxyurea, and caffeine). Long-term exposure (7 h) played a considerable role in the adaptive response to intoxication compared to early responses at 4 h exposure. The data obtained after 4 h of exposure and expressed as EC20 were compared to 50% inhibitory concentration values derived from cell line and ecotoxicological tests. This study demonstrates the versatility of the novel biomarker to complement existing test batteries to assess contaminant exposure and effects.

  4. Co-fermentation of acetate and sugars facilitating microbial lipid production on acetate-rich biomass hydrolysates.

    PubMed

    Gong, Zhiwei; Zhou, Wenting; Shen, Hongwei; Yang, Zhonghua; Wang, Guanghui; Zuo, Zhenyu; Hou, Yali; Zhao, Zongbao K

    2016-05-01

    The process of lignocellulosic biomass routinely produces a stream that contains sugars plus various amounts of acetic acid. As acetate is known to inhibit the culture of microorganisms including oleaginous yeasts, little attention has been paid to explore lipid production on mixtures of acetate and sugars. Here we demonstrated that the yeast Cryptococcus curvatus can effectively co-ferment acetate and sugars for lipid production. When mixtures of acetate and glucose were applied, C. curvatus consumed both substrates simultaneously. Similar phenomena were also observed for acetate and xylose mixtures, as well as acetate-rich corn stover hydrolysates. More interestingly, the replacement of sugar with equal amount of acetate as carbon source afforded higher lipid titre and lipid content. The lipid products had fatty acid compositional profiles similar to those of cocoa butter, suggesting their potential for high value-added fats and biodiesel production. This co-fermentation strategy should facilitate lipid production technology from lignocelluloses. PMID:26874438

  5. Possible Role of Hormones in Treatment of Metastatic Testicular Teratomas: Tumour Regression with Medroxyprogesterone Acetate

    PubMed Central

    Bloom, H. J. G.; Hendry, W. F.

    1973-01-01

    Three patients in a consecutive series of 16 cases of metastatic mallgnant teratoma testis have shown well-marked tumour regression during hormone treatment. In two cases multiple lung metastases had previously failed to respond to actinomycin D therapy, and following treatment with medroxyprogesterone acetate one patient had well-marked selective tumour regression for nine months while the other is alive, well, and free from disease at seven years. The third case was treated with a combination of actinomycin D and medroxyprogesterone acetate and is alive and disease-free at two years. Attention is drawn to this preliminary study in the hope of stimulating interest in the possible value of hormones, either alone or combined with chemotherapy and irradiation, in the treatment of metastatic testicular teratoma. Multicentre prospective clinical trials are now needed if knowledge is to be advanced in this field. ImagesFIG. 1FIG. 2FIG. 3FIG. 6FIG. 7FIG. 8 PMID:4726928

  6. Stability of octreotide acetate in polypropylene syringes.

    PubMed

    Stiles, M L; Allen, L V; Resztak, K E; Prince, S J

    1993-11-01

    The stability of octreotide acetate in polypropylene syringes was studied. Polypropylene syringes were aseptically filled with 1 mL of octreotide acetate 0.2 mg/mL and stored at 3 or 23 degrees C under light protection or light exposure. Three syringes were prepared for each condition and each sampling time. Unopened 5-mL glass vials of the drug served as controls. Samples were removed immediately and at 8, 15, 22, and 29 days and analyzed by high-performance liquid chromatography. At 3 degrees C, octreotide stored in light-protected syringes maintained more than 90% of its initial concentration for up to 29 days. However, at 22 days the concentration in the syringes stored at that temperature and exposed to light was less than 90% when the standard deviation is considered. At 23 degrees C, the drug was stable for only up to 15 days (light protection) and 22 days (light exposure) when the standard deviation is considered. Octreotide acetate in polypropylene syringes was stable for up to 29 days when stored at 3 degrees C and protected from light and for up to 22 days when stored at 23 degrees C and exposed to light.

  7. Ultrasound-assisted dyeing of cellulose acetate.

    PubMed

    Udrescu, C; Ferrero, F; Periolatto, M

    2014-07-01

    The possibility of reducing the use of auxiliaries in conventional cellulose acetate dyeing with Disperse Red 50 using ultrasound technique was studied as an alternative to the standard procedure. Dyeing of cellulose acetate yarn was carried out by using either mechanical agitation alone, with and without auxiliaries, or coupling mechanical and ultrasound agitation in the bath where the temperature range was maintained between 60 and 80 °C. The best results of dyeing kinetics were obtained with ultrasound coupled with mechanical agitation without auxiliaries (90% of bath exhaustion value at 80 °C). Hence the corresponding half dyeing times, absorption rate constants according to Cegarra-Puente modified equation and ultrasound efficiency were calculated confirming the synergic effect of sonication on the dyeing kinetics. Moreover the apparent activation energies were also evaluated and the positive effect of ultrasound added to mechanical agitation was evidenced by the lower value (48 kJ/mol) in comparison with 112 and 169 kJ/mol for mechanical stirring alone with auxiliaries and without, respectively. Finally, the fastness tests gave good values for samples dyed with ultrasound technique even without auxiliaries. Moreover color measurements on dyed yarns showed that the color yield obtained by ultrasound-assisted dyeing at 80 °C of cellulose acetate without using additional chemicals into the dye bath reached the same value yielded by mechanical agitation, but with remarkably shorter time.

  8. Optical Stimulation of Neurons

    PubMed Central

    Thompson, Alexander C.; Stoddart, Paul R.; Jansen, E. Duco

    2014-01-01

    Our capacity to interface with the nervous system remains overwhelmingly reliant on electrical stimulation devices, such as electrode arrays and cuff electrodes that can stimulate both central and peripheral nervous systems. However, electrical stimulation has to deal with multiple challenges, including selectivity, spatial resolution, mechanical stability, implant-induced injury and the subsequent inflammatory response. Optical stimulation techniques may avoid some of these challenges by providing more selective stimulation, higher spatial resolution and reduced invasiveness of the device, while also avoiding the electrical artefacts that complicate recordings of electrically stimulated neuronal activity. This review explores the current status of optical stimulation techniques, including optogenetic methods, photoactive molecule approaches and infrared neural stimulation, together with emerging techniques such as hybrid optical-electrical stimulation, nanoparticle enhanced stimulation and optoelectric methods. Infrared neural stimulation is particularly emphasised, due to the potential for direct activation of neural tissue by infrared light, as opposed to techniques that rely on the introduction of exogenous light responsive materials. However, infrared neural stimulation remains imperfectly understood, and techniques for accurately delivering light are still under development. While the various techniques reviewed here confirm the overall feasibility of optical stimulation, a number of challenges remain to be overcome before they can deliver their full potential. PMID:26322269

  9. Effect of octreotide on stimulated insulin release from pancreatic tissue slices.

    PubMed

    Presti, M E; Burton, F R; Niehoff, M L; Rioux, J; Garvin, P J

    1998-03-01

    This study was designed to investigate a possible mechanism of action by which octreotide acetate causes insulin suppression in the denervated pancreas. Canine tissue slices were placed in a pH-adjusted medium with varying concentrations of glucose and octreotide acetate: Experiment 1, 30 min in basal medium with 0.6 mg/ml glucose; Experiment 2, addition of 6.0 mg/ml glucose; Experiment 3, addition of 4 microg octreotide acetate/70 ml (comparable to 100 microg/25 kg body weight); Experiment 4, addition of 16 microg octreotide acetate/70 ml; Experiment 5, incubation with 6.0 mg glucose/ml and 4 microg octreotide acetate/70 ml; Experiment 6, incubation with 6.0 mg glucose/ml and 16 microg octreotide acetate/70 ml; Experiment 7, preincubation with 4 microg octreotide acetate/70 ml, then with 6.0 mg glucose/ml; and Experiment 8, preincubation with 16 microg octreotide acetate/70 ml, then with 6.0 mg glucose/ml. Medium levels of insulin, glucagon, and amylase were collected at intervals during the incubation periods. There was an appropriate increase in the rate of insulin release to glucose stimulation in the high-glucose (6.0 mg/ml) group. There was no significant inhibition of basal or glucose-stimulated insulin release with either simultaneous or pretreatment of the canine pancreatic tissue slices with either concentration of octreotide acetate. These studies support an indirect mechanism by which octreotide acetate exerts its inhibitory effect on endocrine and exocrine function in the canine pancreas transplant model.

  10. Alterations in central monoamine systems after postnatal lead acetate treatment in rats

    SciTech Connect

    Luthman, J. Univ. of Colorado Health Sciences Center, Denver, CO ); Lindqvist, E.; Olson, L. ); Gerhardt, G.A.; Hoffer, B.H. )

    1994-04-01

    The present study was undertaken to investigate the effect of postnatal lead exposure on central monoamine systems. Newborn male Sprague-Dawley rats were given 1 or 8 mg/kg lead acetate intraperitoneally for 20 days postnatally. Two groups of control rats received sodium acetate, or sodium acetate in oversized litters to compensate for lead-induced malnutrition in the high lead dose group, while nontreated animals also served as controls. At Day 21 or 51 regional tissue levels of monoamines were determined using HPLC techniques. No major changes were seen after the lead exposures in the levels of dopamine, noradrenaline, and serotonin, or metabolites of dopamine and serotonin, when compared to respective control groups. On the other hand, in the control group given sodium acetate in oversized litters some alterations of the monoamine levels were observed in frontal cortex and striatum at Day 21 compared to controls. At Day 51, the striatal homovanillic acid and 5-hydroxyindoleacetic acid levels were higher in the low lead dose group compared to those in the controls, No other changes in the monoamine levels were seen at Day 51. At 50-70 days postnatally, potassium-stimulated dopamine overflow was studied in striatum with in vivo chronoamperometry. In the high lead dose group the amplitudes of signals were lower in both the dorsal and ventral striatum compared to the controls, while no difference was seen in the clearance time of dopamine. The capacity of the dopamine terminals to respond to repeated stimulation was not affected by the lead exposure. Thus, the steady-state levels of monoamines were essentially unaltered after postnatal lead exposure in rats, while functional aspects of striatal dopamine transmission were affected after exposure to the higher dose of lead. These findings support the hypothesis that lead-induced changes in motor skills and exploratory behavior may be related to altered dopamine neurotransmission. 77 refs., 3 figs., 2 tabs.

  11. Experimental evidence of an acetate transporter protein and characterization of acetate activation in aceticlastic methanogenesis of Methanosarcina mazei.

    PubMed

    Welte, Cornelia; Kröninger, Lena; Deppenmeier, Uwe

    2014-10-01

    Aceticlastic methanogens metabolize acetate to methane and carbon dioxide. The central metabolism and the electron transport chains of these organisms have already been investigated. However, no particular attention has been paid to the mechanism by which acetate enters the archaeal cell. In our study we investigated Methanosarcina mazei acetate kinase (Ack) and the acetate uptake reaction. At a concentration of 2 mM acetate, the Ack activity in cell extract of M. mazei was not limiting for the methane formation rate. Instead, the methanogenesis rate was controlled by the substrate concentration and increased 10-fold at 10 mM acetate. Subsequently, we analyzed the involvement of the putative acetate permease MM_0903 using a corresponding deletion mutant. At 2 mM acetate, only 25% of the wild-type methane formation rate was measured in the mutant. This indicated that the supply of acetate to Ack was limiting the rate of methane formation. Moreover, the mutant revealed an increased acetate kinase activity compared with the wild type. These results show for the first time that an acetate transporter is involved in aceticlastic methanogenesis and may be an important factor in the acetate threshold concentration for methanogenesis of Methanosarcina spp. PMID:25088360

  12. Overview on mechanisms of acetic acid resistance in acetic acid bacteria.

    PubMed

    Wang, Bin; Shao, Yanchun; Chen, Fusheng

    2015-02-01

    Acetic acid bacteria (AAB) are a group of gram-negative or gram-variable bacteria which possess an obligate aerobic property with oxygen as the terminal electron acceptor, meanwhile transform ethanol and sugar to corresponding aldehydes, ketones and organic acids. Since the first genus Acetobacter of AAB was established in 1898, 16 AAB genera have been recorded so far. As the main producer of a world-wide condiment, vinegar, AAB have evolved an elegant adaptive system that enables them to survive and produce a high concentration of acetic acid. Some researches and reviews focused on mechanisms of acid resistance in enteric bacteria and made the mechanisms thoroughly understood, while a few investigations did in AAB. As the related technologies with proteome, transcriptome and genome were rapidly developed and applied to AAB research, some plausible mechanisms conferring acetic acid resistance in some AAB strains have been published. In this review, the related mechanisms of AAB against acetic acid with acetic acid assimilation, transportation systems, cell morphology and membrane compositions, adaptation response, and fermentation conditions will be described. Finally, a framework for future research for anti-acid AAB will be provided.

  13. Stimulation of MAP-2 kinase activity in T lymphocytes by anti-CD3 or anti-Ti monoclonal antibody is partially dependent on protein kinase C.

    PubMed

    Nel, A E; Hanekom, C; Rheeder, A; Williams, K; Pollack, S; Katz, R; Landreth, G E

    1990-04-01

    Signaling via the alpha-beta T cell Ag receptor (Ti)-CD3 complex is a complicated event that implicates several protein kinases, most notably protein kinase C (PKC). We have recently identified a serine kinase in T lymphocytes with the following characteristics: molecular mass 43 kDa, in vitro substrate affinity for microtubule associated protein 2 (MAP-2) with a preference for Mn2+ during the catalytic reaction, and elution from DEAE resin over a salt range 100 to 200 mM NaCl. This kinase is activated in a rapidly reversible fashion during ligation of CD3/Ti by a process which involves prior phosphorylation; in vitro exposure of activated 43-kDa MAP-2 kinase (MAP-K) to an immobilized phosphatase abrogated its kinase activity. We now show that a MAP-2K response could also be obtained during treatment with mAb to Ti and the specific PKC agonist, PMA. Although the kinetics of the former response was rapidly reversible, PMA elicited a more prolonged response. The dose responsiveness for PMA was similar to the requirements for PKC activation in intact lymphocytes. Moreover, as with PKC, we found that the CD3-induced MAP-2K response could be further enhanced by using a second layer cross-linking antibody. The specificity of CD3/Ti in the Jurkat cell response is demonstrated by the fact that OKT-11(CD2) and anti-CD4 mAb did not stimulate a MAP-2K response. It was also not possible to elicit a response in a Jurkat cell mutant that lacks surface expression of CD3 and Ti. The specificity of PKC in these events was further explored with the cell permeant diacylglycerol, 1-oleoyl-2-acetylglycerol, and the nonagonist phorbol ester, 4 alpha-phorbol 12,13-didecanoate: whereas the former was an effective inducer of the MAP-2K response, the latter failed to yield any stimulation. Prior exposure of Jurkat cells to 100 mM PMA for 24 h eliminated greater than 60% of the MAP-2K response during anti-CD3 treatment. This response could also be inhibited in dose-dependent fashion by prior

  14. Differential titration of bases in glacial acetic acid.

    PubMed

    Castellano, T; Medwick, T; Shinkai, J H; Bailey, L

    1981-01-01

    A study of bases in acetic acid and their differential titration was carried out. The overall basicity constants for 20 bases were measured in acetic acid, and the differential titration of five binary mixtures of variable delta pKb values in acetic acid was followed using a glass electrode-modified calomel electrode system. Agreement with literature values was good. A leveling diagram was constructed that indicated that bases stronger than aqueous pKb 10 are leveled to an acetous pKb 5.69, whereas weaker bases are not leveled but instead exhibit their own intrinsic basicity, with the acetous pKb to aqueous pKb values being linearly related (slope 1.18, correlation coefficient 0.962). A minimum acetous delta pKb of four units is required for the satisfactory differential titration of two bases in acetic acid.

  15. [Degradation of oxytetracycline with ozonation in acetic acid solvent].

    PubMed

    Li, Shi-Yin; Li, Xiao-Rong; Zhu, Yi-Ping; Zhu, Jiang-Peng; Wang, Guo-Xiang

    2012-12-01

    Use acetic acid as the media of ozone degradation of oxytetracycline (OTC), and effects of the initial dosing ratio of ozone/OTC, ozone flow, free radical scavenger, metal ions on the removal rate of OTC were investigated respectively. The results showed that acetic acid had a high ozone stability and solubility. OTC had a high removal rate and degradation rate in acetic acid solution. With the increase of OTC dosage, the removal rate of OTC decreased in acetic acid. Removal rate of OTC was increased distinctly when ozone flow increased properly. It was also observed that free radical scavenger had a significantly negative effect on OTC ozonation degradation in acetic acid. Furthermore the main reactions of OTC ozone oxidation were direct oxidation and indirect oxidation in acetic acid. When Fe3+ and Co2+ were existent in acetic acid, the degradation of OTC was inhibited significantly.

  16. Acetic acid removal from corn stover hydrolysate using ethyl acetate and the impact on Saccharomyces cerevisiae bioethanol fermentation.

    PubMed

    Aghazadeh, Mahdieh; Ladisch, Michael R; Engelberth, Abigail S

    2016-07-01

    Acetic acid is introduced into cellulose conversion processes as a consequence of composition of lignocellulose feedstocks, causing significant inhibition of adapted, genetically modified and wild-type S. cerevisiae in bioethanol fermentation. While adaptation or modification of yeast may reduce inhibition, the most effective approach is to remove the acetic acid prior to fermentation. This work addresses liquid-liquid extraction of acetic acid from biomass hydrolysate through a pathway that mitigates acetic acid inhibition while avoiding the negative effects of the extractant, which itself may exhibit inhibition. Candidate solvents were selected using simulation results from Aspen Plus™, based on their ability to extract acetic acid which was confirmed by experimentation. All solvents showed varying degrees of toxicity toward yeast, but the relative volatility of ethyl acetate enabled its use as simple vacuum evaporation could reduce small concentrations of aqueous ethyl acetate to minimally inhibitory levels. The toxicity threshold of ethyl acetate, in the presence of acetic acid, was found to be 10 g L(-1) . The fermentation was enhanced by extracting 90% of the acetic acid using ethyl acetate, followed by vacuum evaporation to remove 88% removal of residual ethyl acetate along with 10% of the broth. NRRL Y-1546 yeast was used to demonstrate a 13% increase in concentration, 14% in ethanol specific production rate, and 11% ethanol yield. This study demonstrated that extraction of acetic acid with ethyl acetate followed by evaporative removal of ethyl acetate from the raffinate phase has potential to significantly enhance ethanol fermentation in a corn stover bioethanol facility. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:929-937, 2016.

  17. Acetic acid removal from corn stover hydrolysate using ethyl acetate and the impact on Saccharomyces cerevisiae bioethanol fermentation.

    PubMed

    Aghazadeh, Mahdieh; Ladisch, Michael R; Engelberth, Abigail S

    2016-07-01

    Acetic acid is introduced into cellulose conversion processes as a consequence of composition of lignocellulose feedstocks, causing significant inhibition of adapted, genetically modified and wild-type S. cerevisiae in bioethanol fermentation. While adaptation or modification of yeast may reduce inhibition, the most effective approach is to remove the acetic acid prior to fermentation. This work addresses liquid-liquid extraction of acetic acid from biomass hydrolysate through a pathway that mitigates acetic acid inhibition while avoiding the negative effects of the extractant, which itself may exhibit inhibition. Candidate solvents were selected using simulation results from Aspen Plus™, based on their ability to extract acetic acid which was confirmed by experimentation. All solvents showed varying degrees of toxicity toward yeast, but the relative volatility of ethyl acetate enabled its use as simple vacuum evaporation could reduce small concentrations of aqueous ethyl acetate to minimally inhibitory levels. The toxicity threshold of ethyl acetate, in the presence of acetic acid, was found to be 10 g L(-1) . The fermentation was enhanced by extracting 90% of the acetic acid using ethyl acetate, followed by vacuum evaporation to remove 88% removal of residual ethyl acetate along with 10% of the broth. NRRL Y-1546 yeast was used to demonstrate a 13% increase in concentration, 14% in ethanol specific production rate, and 11% ethanol yield. This study demonstrated that extraction of acetic acid with ethyl acetate followed by evaporative removal of ethyl acetate from the raffinate phase has potential to significantly enhance ethanol fermentation in a corn stover bioethanol facility. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:929-937, 2016. PMID:27090191

  18. STIMULATION OF REDUCTIVE DECHLORINATION OF TETRA- CHLOROETHENE (PCE) IN ANAEROBIC AQUIFER MICROCOSMS BY ADDITION OF SHORT-CHAIN ORGANIC ACIDS OR ALCOHOLS

    EPA Science Inventory

    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, ...

  19. Adaptation and tolerance of bacteria against acetic acid.

    PubMed

    Trček, Janja; Mira, Nuno Pereira; Jarboe, Laura R

    2015-08-01

    Acetic acid is a weak organic acid exerting a toxic effect to most microorganisms at concentrations as low as 0.5 wt%. This toxic effect results mostly from acetic acid dissociation inside microbial cells, causing a decrease of intracellular pH and metabolic disturbance by the anion, among other deleterious effects. These microbial inhibition mechanisms enable acetic acid to be used as a preservative, although its usefulness is limited by the emergence of highly tolerant spoilage strains. Several biotechnological processes are also inhibited by the accumulation of acetic acid in the growth medium including production of bioethanol from lignocellulosics, wine making, and microbe-based production of acetic acid itself. To design better preservation strategies based on acetic acid and to improve the robustness of industrial biotechnological processes limited by this acid's toxicity, it is essential to deepen the understanding of the underlying toxicity mechanisms. In this sense, adaptive responses that improve tolerance to acetic acid have been well studied in Escherichia coli and Saccharomyces cerevisiae. Strains highly tolerant to acetic acid, either isolated from natural environments or specifically engineered for this effect, represent a unique reservoir of information that could increase our understanding of acetic acid tolerance and contribute to the design of additional tolerance mechanisms. In this article, the mechanisms underlying the acetic acid tolerance exhibited by several bacterial strains are reviewed, with emphasis on the knowledge gathered in acetic acid bacteria and E. coli. A comparison of how these bacterial adaptive responses to acetic acid stress fit to those described in the yeast Saccharomyces cerevisiae is also performed. A systematic comparison of the similarities and dissimilarities of the ways by which different microbial systems surpass the deleterious effects of acetic acid toxicity has not been performed so far, although such exchange

  20. Temperature dependence of ion transport in dilute tetrabutylammonium triflate-acetate solutions and self-diffusion in pure acetate liquids.

    PubMed

    Bopege, Dharshani N; Petrowsky, Matt; Fleshman, Allison M; Frech, Roger; Johnson, Matthew B

    2012-01-12

    Conductivities and static dielectric constants for 0.0055 M tetrabutylammonium trifluoromethanesulfonate in n-butyl acetate, n-pentyl acetate, n-hexyl acetate, n-octyl acetate, and n-decyl acetate have been collected over the temperature range of 0-80 °C. Self-diffusion coefficients and static dielectric constants of pure acetates were obtained over the same temperature range. Both temperature-dependent diffusion coefficients and ionic conductivities of these pure acetates and dilute acetate solutions can be accurately described by the compensated Arrhenius formalism. Activation energies were calculated from compensated Arrhenius plots for both conductivity and diffusion data. Activation energies are higher for conductivity data of 0.0055 M TbaTf-acetates compared to diffusion data of pure acetates. The plot of the exponential prefactor versus the dielectric constant yields a single master curve for both conductivity and diffusion data. These data support the argument that mass and charge transport are thermally activated processes in the acetates, as previously observed in alcohol-based electrolytes. PMID:22145961

  1. [The characteristics of the wound-healing action of solubilized alpha-tocopherol acetate].

    PubMed

    Samoĭlov, A V; Seĭfulla, R D; Shekhter, A B; Volozhin, A I; Denisov, A B; Druzhinina, R A; Pomerantseva, E N; Kamaev, N O; Belous, M V

    1993-01-01

    The rat experiments were made to compare the wound-healing action of solubilized (aqueous) alpha-tocopherol acetate (SATA) prepared by the original techniques and its official oil-based preparation. A course intravenous SATA (2 mg four times at an interval of 4 days) administration was found to stimulate epithelial regeneration and suppress the formation of connective tissue of uncomplicated skin wounds. By healing the complicated wounds, SATA potentiated the occurrence of an inflammatory reaction and slowed down regeneration, whereas its oily solution failed to produce this effect.

  2. Radiolabeled acetate as a tracer of myocardial tricarboxylic acid cycle flux

    SciTech Connect

    Buxton, D.B.; Schwaiger, M.; Nguyen, A.; Phelps, M.E.; Schelbert, H.R.

    1988-09-01

    The kinetics of (1-14C)acetate oxidation in isolated perfused rat hearts have been determined over a range of perfusion conditions. Effluent measurements demonstrated that 14CO2 cleared biexponentially over 50 minutes after bolus injection of (1-14C)acetate into normoxic hearts perfused with 5 mM glucose and 10 mU/ml insulin. The clearance half-time (t1/2) for the predominant initial clearance phase was 3.1 +/- 0.5 minutes (n = 4). MVO2 was varied over a fourfold range by hypoxia and phenylephrine stimulation (t1/2, 7.2 +/- 1.2 and 2.2 +/- 0.2 minutes, respectively) and in the presence of alternate substrates (lactate, 2 mM; DL-3-hydroxybutyrate, 20 mM; and palmitate, 0.1 mM), which did not modify either tricarboxylic acid (TCA) cycle flux or acetate kinetics. A good correlation (r = 0.93) was observed between k, the rate constant for the initial phase of 14CO2 clearance, and TCA cycle flux, estimated from oxygen consumption. In contrast to results with (1-14C)acetate, lactate (2 mM) increased t1/2 for 14CO2 clearance from a bolus injection of (1-14C)palmitate from 3.0 +/- 0.4 minutes (n = 3) at control to 4.3 +/- 0.2 minutes (n = 3, p less than 0.01). Addition of acetate in nontracer amounts (0.5 or 5 mM) caused significant underestimation of TCA cycle flux when estimated with (1-14C)acetate. 14CO2 clearance accounted for 88-98% of total effluent 14C between 10 and 20 minutes after (1-14C)acetate bolus injection; rate constants for clearance of 14CO2 and total 14C clearance were very similar during this period, and these two rate constants did not differ significantly from each other under any conditions tested.

  3. Acetate availability and its influence on sustainable bioremediation of Uranium-contaminated groundwater

    USGS Publications Warehouse

    Williams, K.H.; Long, P.E.; Davis, J.A.; Wilkins, M.J.; N'Guessan, A. L.; Steefel, Carl; Yang, L.; Newcomer, D.; Spane, F.A.; Kerkhof, L.J.; Mcguinness, L.; Dayvault, R.; Lovley, D.R.

    2011-01-01

    Field biostimulation experiments at the U.S. Department of Energy's Integrated Field Research Challenge (IFRC) site in Rifle, Colorado, have demonstrated that uranium concentrations in groundwater can be decreased to levels below the U.S. Environmental Protection Agency's (EPA) drinking water standard (0.126??M).During successive summer experiments - referred to as "Winchester" (2007) and "Big Rusty" (2008) - acetate was added to the aquifer to stimulate the activity of indigenous dissimilatory metal reducing bacteria capable of reductively immobilizing uranium. The two experiments differed in the length of injection (31 vs. 110 days), the maximum concentration of acetate (5 vs. 30 mM),and the extent to which iron reduction ("Winchester") or sulfate reduction("Big Rusty") was the predominant metabolic process. In both cases, rapid removal of U(VI) from groundwater occurred at calcium concentrations (6 mM) and carbonate alkalinities (8 meq/L) where Ca-UO2-CO3 ternary complexes constitute >90% of uranyl species in groundwater. Complete consumption of acetate and increased alkalinity (>30 meq/L) accompanying the onset of sulfate reduction corresponded to temporary increases in U(VI);however, by increasing acetate concentrations in excess of available sulfate (10 mM), low U(VI) concentrations (0.1-0.05 ??M) were achieved for extended periods of time (>140 days). Uniform delivery of acetate during "Big Rusty" was impeded due to decreases in injection well permeability, likely resulting from biomass accumulation and carbonate and sulfide mineral precipitation. Such decreases were not observed during the short-duration "Winchester" experiment. Terminal restriction fragment length polymorphism (TRFLP) analysis of 16S rRNA genes demonstrated that Geobacter sp. and Geobacter-like strains dominated the groundwater community profile during iron reduction, with 13C stable isotope probing (SIP) results confirming these strains were actively utilizing acetate to replicate their

  4. Acetate availability and its influence on sustainable bioremediation of uranium-contaminated groundwater

    SciTech Connect

    Williams, Kenneth H.; Long, Philip E.; Davis, James A.; Wilkins, Michael J.; N'Guessan, A. Lucie; Steefel, Carl I.; Yang, Li; Newcomer, Darrell R.; Spane, Frank A.; Kerkhof, L.; McGuinness, L.; Dayvault, Richard; Lovley, Derek

    2011-11-01

    Field biostimulation experiments at the U.S. Department of Energy's Integrated Field Research Challenge (IFRC) site in Rifle, Colorado, have demonstrated that uranium concentrations in groundwater can be decreased to levels below the U.S. Environmental Protection Agency's (EPA) drinking water standard (0.126 {micro}M). During successive summer experiments - referred to as 'Winchester' (2007) and 'Big Rusty' (2008) - acetate was added to the aquifer to stimulate the activity of indigenous dissimilatory metal-reducing bacteria capable of reductively immobilizing uranium. The two experiments differed in the length of injection (31 vs. 110 days), the maximum concentration of acetate (5 vs. 30 mM), and the extent to which iron reduction ('Winchester') or sulfate reduction ('Big Rusty') was the predominant metabolic process. In both cases, rapid removal of U(VI) from groundwater occurred at calcium concentrations (6 mM) and carbonate alkalinities (8 meq/L) where Ca-UO2-CO3 ternary complexes constitute >90% of uranyl species in groundwater. Complete consumption of acetate and increased alkalinity (>30 meq/L) accompanying the onset of sulfate reduction corresponded to temporary increases in U(VI); however, by increasing acetate concentrations in excess of available sulfate (10 mM), low U(VI) concentrations (0.1-0.05 {micro}M) were achieved for extended periods of time (>140 days). Uniform delivery of acetate during 'Big Rusty' was impeded due to decreases in injection well permeability, likely resulting from biomass accumulation and carbonate and sulfide mineral precipitation. Such decreases were not observed during the short-duration 'Winchester' experiment. Terminal restriction fragment length polymorphism (TRFLP) analysis of 16S rRNA genes demonstrated that Geobacter sp. and Geobacter-like strains dominated the groundwater community profile during iron reduction, with 13C stable isotope probing (SIP) results confirming these strains were actively utilizing acetate to

  5. Acetate supplementation attenuates lipopolysaccharide-induced neuroinflammation.

    PubMed

    Reisenauer, Chris J; Bhatt, Dhaval P; Mitteness, Dane J; Slanczka, Evan R; Gienger, Heidi M; Watt, John A; Rosenberger, Thad A

    2011-04-01

    Glyceryl triacetate (GTA), a compound effective at increasing circulating and tissue levels of acetate was used to treat rats subjected to a continual 28 day intra-ventricular infusion of bacterial lipopolysaccharide (LPS). This model produces a neuroinflammatory injury characterized by global neuroglial activation and a decrease in choline acetyltransferase immunoreactivity in the basal forebrain. During the LPS infusion, rats were given a daily treatment of either water or GTA at a dose of 6 g/kg by oral gavage. In parallel experiments, free-CoA and acetyl-CoA levels were measured in microwave fixed brains and flash frozen heart, liver, kidney and muscle following a single oral dose of GTA. We found that a single oral dose of GTA significantly increased plasma acetate levels by 15 min and remained elevated for up to 4 h. At 30 min the acetyl-CoA levels in microwave-fixed brain and flash frozen heart and liver were increased at least 2.2-fold. The concentrations of brain acetyl-CoA was significantly increased between 30 and 45 min following treatment and remained elevated for up to 4 h. The concentration of free-CoA in brain was significantly decreased compared to controls at 240 min. Immunohistochemical and morphological analysis demonstrated that a daily treatment with GTA significantly reduced the percentage of reactive glial fibrillary acidic protein-positive astrocytes and activated CD11b-positive microglia by 40-50% in rats subjected to LPS-induced neuroinflammation. Further, in rats subjected to neuroinflammation, GTA significantly increased the number of choline acetyltransferase (ChAT)-positive cells by 40% in the basal forebrain compared to untreated controls. These data suggest that acetate supplementation increases intermediary short chain acetyl-CoA metabolism and that treatment is potentially anti-inflammatory and neuroprotective with regards to attenuating neuroglial activation and increasing ChAT immunoreactivity in this model. PMID:21272004

  6. High-flux cellulose acetate membranes

    SciTech Connect

    Boeddeker, K.W.; Finken, H.; Wenzlaff, A.

    1981-01-01

    Three routes to increase the permeate flux of asymmetric cellulose diacetate membranes of the Loeb-Sourirajan type were investigated: increasing the hydrophilicity of the membranes; increasing their compaction stability, and employing a swelling agent which allows for higher solvent-to-polymer ratio in the casting solution. The effect of casting solution composition on flux and rejection of formamide-modified cellulose acetate membrane is included, illustrating the general capability of this membrane type as function of solvent concentration. Membranes of casting solution composition cellulose diacetate/acetone/formamide 23/52/25 were used as reference membranes in the work. 6 figures. (DP)

  7. Effect of leuprolide acetate on ovarian function after cyclophosphamide-doxorubicin-based chemotherapy in premenopausal patients with breast cancer: results from a phase II randomized trial.

    PubMed

    Song, Guiping; Gao, Hui; Yuan, Zhixiang

    2013-01-01

    Previous studies provided inconclusive evidence for the effectiveness of gonadotropin-releasing hormone analogue on ovarian function protection against chemotherapy-induced genotoxicity in premenopausal patients. This study was designed to examine the efficacy of leuprolide acetate on ovarian function preservation in patients with breast cancer. A total of 220 patients were recruited in this prospective clinical trial and were assigned randomly to receive cyclophosphamide-doxorubicin-based chemotherapy only or chemotherapy plus leuprolide acetate. Resumption of menses or premenopausal levels of both follicle-stimulating hormone (FSH) and estradiol (E2) within 12 months after the end of chemotherapy were considered as effective ovarian preservation. A total of 183 patients were considered evaluable (94 in chemotherapy-only group and 89 in chemotherapy plus leuprolide acetate group). At the end of follow-up, 27 patients in chemotherapy group and 15 in chemotherapy plus leuprolide acetate group resumed menses; seven patients in chemotherapy group and 14 in chemotherapy plus leuprolide acetate group restored premenopausal levels of FSH and E2. The median time to resume menses was 9.2 months for patients in chemotherapy plus leuprolide acetate group and was not reached in chemotherapy-only group. In addition, our results demonstrated that age and chemotherapy doses made no significant difference in the occurrence of premature menopause. The leuprolide acetate treatment simultaneously with cyclophosphamide-doxorubicin-based chemotherapy reduced the risk of developing premature menopause in premenopausal patients with breast cancer.

  8. Long-term continuous evolution of acetate resistant Acetobacter aceti.

    PubMed

    Steiner, Peter; Sauer, Uwe

    2003-10-01

    Elevated concentrations of cytotoxic acetate are found in many environmental niches, and few species are relatively resistant to acetate. In particular the high-level acetate resistance of so-called acetic acid bacteria that occurs in industrial settings must be constantly selected for. To investigate the nature of such high-level resistance, we grew the moderately acetate-resistant Acetobacter aceti wild-type and acetate-sensitive Escherichia coli in long-term continuous cultures with increasing acetate concentrations at near neutral pH. While E. coli did not acquire any significant resistance after 125 generations of selection, A. aceti evolved the capability to grow at acetate concentrations exceeding 50 g/L within 240 generations. This phenotype was found to be stable for several generations in the absence of selective pressure, hence must be genetically determined. Intracellular acetate concentrations were significantly lower in evolved A. aceti, when compared to wild-type A. aceti and E. coli, indicating that cytoplasmatic anion accumulation is an important component of acetate toxicity.

  9. Sphingolipids contribute to acetic acid resistance in Zygosaccharomyces bailii.

    PubMed

    Lindahl, Lina; Genheden, Samuel; Eriksson, Leif A; Olsson, Lisbeth; Bettiga, Maurizio

    2016-04-01

    Lignocellulosic raw material plays a crucial role in the development of sustainable processes for the production of fuels and chemicals. Weak acids such as acetic acid and formic acid are troublesome inhibitors restricting efficient microbial conversion of the biomass to desired products. To improve our understanding of weak acid inhibition and to identify engineering strategies to reduce acetic acid toxicity, the highly acetic-acid-tolerant yeast Zygosaccharomyces bailii was studied. The impact of acetic acid membrane permeability on acetic acid tolerance in Z. bailii was investigated with particular focus on how the previously demonstrated high sphingolipid content in the plasma membrane influences acetic acid tolerance and membrane permeability. Through molecular dynamics simulations, we concluded that membranes with a high content of sphingolipids are thicker and more dense, increasing the free energy barrier for the permeation of acetic acid through the membrane. Z. bailii cultured with the drug myriocin, known to decrease cellular sphingo-lipid levels, exhibited significant growth inhibition in the presence of acetic acid, while growth in medium without acetic acid was unaffected by the myriocin addition. Furthermore, following an acetic acid pulse, the intracellular pH decreased more in myriocin-treated cells than in control cells. This indicates a higher inflow rate of acetic acid and confirms that the reduction in growth of cells cultured with myriocin in the medium with acetic acid was due to an increase in membrane permeability, thereby demonstrating the importance of a high fraction of sphingolipids in the membrane of Z. bailii to facilitate acetic acid resistance; a property potentially transferable to desired production organisms suffering from weak acid stress. PMID:26416641

  10. Sphingolipids contribute to acetic acid resistance in Zygosaccharomyces bailii.

    PubMed

    Lindahl, Lina; Genheden, Samuel; Eriksson, Leif A; Olsson, Lisbeth; Bettiga, Maurizio

    2016-04-01

    Lignocellulosic raw material plays a crucial role in the development of sustainable processes for the production of fuels and chemicals. Weak acids such as acetic acid and formic acid are troublesome inhibitors restricting efficient microbial conversion of the biomass to desired products. To improve our understanding of weak acid inhibition and to identify engineering strategies to reduce acetic acid toxicity, the highly acetic-acid-tolerant yeast Zygosaccharomyces bailii was studied. The impact of acetic acid membrane permeability on acetic acid tolerance in Z. bailii was investigated with particular focus on how the previously demonstrated high sphingolipid content in the plasma membrane influences acetic acid tolerance and membrane permeability. Through molecular dynamics simulations, we concluded that membranes with a high content of sphingolipids are thicker and more dense, increasing the free energy barrier for the permeation of acetic acid through the membrane. Z. bailii cultured with the drug myriocin, known to decrease cellular sphingo-lipid levels, exhibited significant growth inhibition in the presence of acetic acid, while growth in medium without acetic acid was unaffected by the myriocin addition. Furthermore, following an acetic acid pulse, the intracellular pH decreased more in myriocin-treated cells than in control cells. This indicates a higher inflow rate of acetic acid and confirms that the reduction in growth of cells cultured with myriocin in the medium with acetic acid was due to an increase in membrane permeability, thereby demonstrating the importance of a high fraction of sphingolipids in the membrane of Z. bailii to facilitate acetic acid resistance; a property potentially transferable to desired production organisms suffering from weak acid stress.

  11. Fast determination of urinary S-phenylmercapturic acid (S-PMA) and S-benzylmercapturic acid (S-BMA) by column-switching liquid chromatography-tandem mass spectrometry.

    PubMed

    Schettgen, T; Musiol, A; Alt, A; Kraus, T

    2008-03-01

    Benzene and toluene are important industrial chemicals and ubiquitous environmental pollutants. The urinary mercapturic acids of benzene and toluene, S-phenylmercapturic acid (S-PMA) and S-benzylmercapturic acids (S-BMA) are specific biomarkers for the determination of low-level exposures. We have developed and validated a fast, specific and very sensitive method for the simultaneous determination of S-PMA and S-BMA in human urine using an automated multidimensional LC-MS-MS-method that requires no additional sample preparation. Analytes are stripped from urinary matrix by online extraction on a restricted access material, transferred to the analytical column and subsequently determined by tandem mass spectrometry using isotopically labelled S-PMA as internal standard. The lower limit of quantification (LLOQ) for both analytes was 0.05 microg/L urine and sufficient to quantify the background exposure of the general population. Precision within series and between series for S-PMA and S-BMA ranged from 1.0% to 12.2%, accuracy was 108% and 100%, respectively. We applied the method on spot urine samples of 30 subjects of the general population with no known exposure to benzene or toluene. Median levels (range) for S-PMA and S-BMA in non-smokers (n=15) were 0.14 microg/L (<0.05-0.26 microg/L) and 8.2 (1.6-77.4 microg/L), respectively. In smokers (n=15), median levels for S-PMA and S-BMA were 1.22 microg/L (0.17-5.75 microg/L) and 11.5 microg/L (0.9-51.2 microg/L), respectively. Due to its automation, our method is well suited for application in large environmental studies.

  12. Signals involved in T cell activation. II. Distinct roles of intact accessory cells, phorbol esters, and interleukin 1 in activation and cell cycle progression of resting T lymphocytes

    SciTech Connect

    Davis, L.; Lipsky, P.E.

    1986-05-15

    The signals involved in the initiation of mitogen-induced activation of resting guinea pig T cells were examined. The combination of phytohemagglutinin (PHA) and 4..beta..-phorbol 12-myristate 13-acetate (PMA) stimulated DNA synthesis by accessory cell (AC)-depleted T cells cultured at high density, but the use of low density cultures indicated that intact AC were absolutely necessary for PHA-stimulated T cell DNA synthesis even in the presence of PMA, interleukin 1 (IL 1), or interleukin 2 (IL 2). In contrast, AC-depleted T cells were able to respond to the combination of the calcium ionophore, ionomycin, and PMA regardless of the cell density at which they were cultured. Results of cell cycle analysis support the conclusion that intact AC, IL 1, and a PMA-like signal play distinct roles in the progression of mitogen stimulated T cells through the first round of the cell cycle.

  13. Estradiol suppression and recovery during leuprolide acetate treatment in women as determined weekly by an ultrasensitive recombinant cell bioassay.

    PubMed

    Larmore, K A; Klein, K O

    2000-12-01

    We studied the time frame of suppression and recovery of estradiol after injection with leuprolide acetate utilizing an ultrasensitive recombinant cell bioassay for estradiol in eight normal premenopausal women. Previous studies have shown suppression of gonadotropins and estradiol at 4 weeks after the depot injection, but no studies have shown the weekly time course of estradiol suppression or recovery. Four women received one 3.75 mg i.m. injection of leuprolide acetate and four received two 3.75 mg doses of leuprolide acetate 4 weeks apart. Estradiol, luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels were measured weekly for 8 to 12 weeks. Estradiol was significantly suppressed to 26.6 +/- 19.3% of baseline values by week 3 after the initial dose of leuprolide acetate and suppressed to 2.7 +/- 3.1% of baseline values by week 4 (p < 0.01 versus baseline). The actual values were less than 14.7 pmol/l (4 pg/ml) in all women by week 4. Estradiol remained suppressed for 8 weeks after one dose of leuprolide acetate and remained suppressed for 6 weeks after a second dose administered 4 weeks later. LH and FSH followed a similar pattern, but only remained suppressed for 7 weeks after one dose of leuprolide acetate and for 6 weeks after two doses. Estradiol levels at baseline were significantly correlated with body mass index (BMI). We also studied one postmenopausal woman. Her baseline estradiol levels were 10.3 pmol/l (2.8 pg/ml) and were suppressed to 3.9 pmol/l (1.1 pg/ml) by 2 weeks after leuprolide acetate. In conclusion, estradiol was suppressed to postmenopausal levels by the end of the first month of treatment with leuprolide acetate, as determined by an ultrasensitive bioassay. Higher doses would need to be tested to determine whether greater suppression can be achieved. The hypothalamic-pituitary-gonadal axis begins to recover 7 weeks after one dose and 6 weeks after a second dose of leuprolide acetate. This confirms the adequacy of 4-week

  14. Immunotoxicity of trenbolone acetate in Japanese quail

    USGS Publications Warehouse

    Quinn, M.J.; McKernan, M.; Lavoie, E.T.; Ottinger, M.A.

    2007-01-01

    Trenbolone acetate is a synthetic androgen that is currently used as a growth promoter in many meat-exporting countries. Despite industry laboratories classifying trenbolone as nonteratogenic, data showed that embryonic exposure to this androgenic chemical altered development of the immune system in Japanese quail. Trenbolone is lipophilic, persistent, and released into the environment in manure used as soil fertilizer. This is the first study to date to assess this chemical's immunotoxic effects in an avian species. A one-time injection of trenbolone into yolks was administered to mimic maternal deposition, and subsequent effects on the development and function of the immune system were determined in chicks and adults. Development of the bursa of Fabricius, an organ responsible for development of the humoral arm of the immune system, was disrupted, as indicated by lower masse, and smaller and fewer follicles at day 1 of hatch. Morphological differences in the bursas persisted in adults, although no differences in either two measures of immune function were observed. Total numbers of circulating leukocytes were reduced and heterophil-lymphocyte ratios were elevated in chicks but not adults. This study shows that trenbolone acetate is teratogenic and immunotoxic in Japanese quail, and provides evidence that the quail immune system may be fairly resilient to embryonic endocrine-disrupting chemical-induced alterations following no further exposure posthatch.

  15. Phorbol esters modulate cyclic AMP accumulation in porcine thyroid cells

    SciTech Connect

    Emoto, T.; Kasai, K.; Hiraiwa, M.; Shimoda, S.

    1988-01-01

    In cultured porcine thyroid cells, during 60 min incubation phorbol 12-myristate 13-acetate (PMA) had no effect on basal cyclic AMP accumulation and slightly stimulated cyclic AMP accumulation evoked by thyroid stimulating hormone (TSH) or forskolin. Cholera toxin-induced cyclic AMP accumulation was significantly stimulated by PMA. On the other hand, cyclic AMP accumulation evoked by prostaglandin E/sub 1/ or E/sub 2/ (PGE/sub 1/ and PGE/sub 2/) was markedly depressed by simultaneous addition of PMA. These opposing effects of PMA on cyclic AMP accumulation evoked by PGE and cholera toxin were observed in a dose-related fashion, with half-maximal effect of around 10/sup -9/ M in either case. The almost same effects of PMA on cyclic AMP accumulation in basal and stimulated conditions were also observed in freshly prepared thyroid cells. The present study was performed in the presence of phosphodiesterase inhibitor, 3-iso-butyl-1-methylxanthine (IBMX), indicating that PMA affected adenylate cyclase activity. Therefore, it is suggested that PMA may modulate the production of cyclic AMP in response to different stimuli, possibly by affecting several sites in the adenylate cyclase complex in thyroid cells.

  16. Genetic dissection of acetic acid tolerance in Saccharomyces cerevisiae.

    PubMed

    Geng, Peng; Xiao, Yin; Hu, Yun; Sun, Haiye; Xue, Wei; Zhang, Liang; Shi, Gui-Yang

    2016-09-01

    Dissection of the hereditary architecture underlying Saccharomyces cerevisiae tolerance to acetic acid is essential for ethanol fermentation. In this work, a genomics approach was used to dissect hereditary variations in acetic acid tolerance between two phenotypically different strains. A total of 160 segregants derived from these two strains were obtained. Phenotypic analysis indicated that the acetic acid tolerance displayed a normal distribution in these segregants, and suggested that the acetic acid tolerant traits were controlled by multiple quantitative trait loci (QTLs). Thus, 220 SSR markers covering the whole genome were used to detect QTLs of acetic acid tolerant traits. As a result, three QTLs were located on chromosomes 9, 12, and 16, respectively, which explained 38.8-65.9 % of the range of phenotypic variation. Furthermore, twelve genes of the candidates fell into the three QTL regions by integrating the QTL analysis with candidates of acetic acid tolerant genes. These results provided a novel avenue to obtain more robust strains.

  17. Peripheral nerve stimulation: definition.

    PubMed

    Abejón, David; Pérez-Cajaraville, Juan

    2011-01-01

    Recently, there has been a tremendous evolution in the field of neurostimulation, both from the technological point of view and from development of the new and different indications. In some areas, such as peripheral nerve stimulation, there has been a boom in recent years due to the variations in the surgical technique and the improved results documented by in multiple published papers. All this makes imperative the need to classify and define the different types of stimulation that are used today. The confusion arises when attempting to describe peripheral nerve stimulation and subcutaneous stimulation. Peripheral nerve stimulation, in its pure definition, involves implanting a lead on a nerve, with the aim to produce paresthesia along the entire trajectory of the stimulated nerve.

  18. Formic acid and acetic acid induce a programmed cell death in pathogenic Candida species.

    PubMed

    Lastauskienė, Eglė; Zinkevičienė, Auksė; Girkontaitė, Irutė; Kaunietis, Arnoldas; Kvedarienė, Violeta

    2014-09-01

    Cutaneous fungal infections are common and widespread. Antifungal agents used for the treatment of these infections often have undesirable side effects. Furthermore, increased resistance of the microorganisms to the antifungal drugs becomes the growing problem. Accordingly, the search for natural antifungal compounds continues to receive attention. Apoptosis is highly regulated programmed cell death. During yeast cell apoptosis, amino acids and peptides are released and can stimulate regeneration of human epithelium cells. Thus, detection of chemical compounds inducing apoptosis in yeast and nontoxic for humans is of great medical relevance. The aim of this study was to detect chemical compound inducing apoptosis in pathogenic Candida species with the lowest toxicity to the mammalian cells. Five chemical compounds--acetic acid, sodium bicarbonate, potassium carbonate, lithium acetate, and formic acid--were tested for evaluation of antifungal activity on C. albicans, C. guilliermondii, and C. lusitaniae. The results showed that acetic acid and formic acid at the lowest concentrations induced yeast cells death. Apoptosis analysis revealed that cells death was accompanied by activation of caspase. Minimal inhibitory concentrations of potassium carbonate and sodium bicarbonate induced Candida cells necrosis. Toxicity test with mammalian cell cultures showed that formic acid has the lowest effect on the growth of Jurkat and NIH 3T3 cells. In conclusion, our results show that a low concentration of formic acid induces apoptosis-like programmed cell death in the Candida yeast and has a minimal effect on the survivability of mammalian cells, suggesting potential applications in the treatment of these infections. PMID:24752490

  19. Enzymes involved in vinyl acetate decomposition by Pseudomonas fluorescens PCM 2123 strain.

    PubMed

    Szczyrba, Elżbieta; Greń, Izabela; Bartelmus, Grażyna

    2014-03-01

    Esterases are widely used in food processing industry, but there is little information concerning enzymes involved in decompositions of esters contributing to pollution of environment. Vinyl acetate (an ester of vinyl alcohol and acetic acid) is a representative of volatile organic compounds (VOCs) in decomposition, of which hydrolyses and oxidoreductases are mainly involved. Their activities under periodically changing conditions of environment are essential for the removal of dangerous VOCs. Esterase and alcohol/aldehyde dehydrogenase activities were determined in crude cell extract from Pseudomonas fluorescens PMC 2123 after vinyl acetate induction. All examined enzymes exhibit their highest activity at 30-35 °C and pH 7.0-7.5. Esterase preferably hydrolyzed ester bonds with short fatty chains without plain differences for C2 or C4. Comparison of Km values for alcohol and aldehyde dehydrogenases for acetaldehyde suggested that this metabolite was preferentially oxidized than reduced. Activity of alcohol dehydrogenase reducing acetaldehyde to ethanol suggested that one mechanism of defense against the elevated concentration of toxic acetaldehyde could be its temporary reduction to ethanol. Esterase activity was inhibited by phenylmethanesulfonyl fluoride, while β-mercaptoethanol, dithiothreitol, and ethylenediaminetetraacetic acid had no inhibitor effect. From among metal ions, only Mg(2+) and Fe(2+) stimulated the cleavage of ester bond.

  20. Methane production from formate, acetate and H2/CO2; focusing on kinetics and microbial characterization.

    PubMed

    Pan, Xiaofang; Angelidaki, Irini; Alvarado-Morales, Merlin; Liu, Houguang; Liu, Yuhong; Huang, Xu; Zhu, Gefu

    2016-10-01

    For evaluating the methanogenesis from typical methanogenic precursors (formate, acetate and H2/CO2), CH4 production kinetics were investigated at 37±1°C in batch anaerobic digestion tests and stimulated by modified Gompertz model. The results showed that maximum methanation rate from formate, acetate and H2/CO2 were 19.58±0.49, 42.65±1.17 and 314.64±3.58NmL/gVS/d in digested manure system and 6.53±0.31, 132.04±3.96 and 640.16±19.92NmL/gVS/d in sewage sludge system during second generation incubation. Meanwhile the model could not fit well in granular sludge system, while the rate of formate methanation was faster than from H2/CO2 and acetate. Considering both the kinetic results and microbial assay we could conclude that H2/CO2 methanation was the fastest methanogenic step in digested manure and sewage sludge system with Methanomicrobiales as dominant methanogens, while granular sludge with Methanobacteriales as dominant methanogens contributed to the fastest formate methanation. PMID:27423547

  1. Sphingolipids contribute to acetic acid resistance in Zygosaccharomyces bailii

    PubMed Central

    Lindahl, Lina; Genheden, Samuel; Eriksson, Leif A.; Olsson, Lisbeth

    2015-01-01

    ABSTRACT Lignocellulosic raw material plays a crucial role in the development of sustainable processes for the production of fuels and chemicals. Weak acids such as acetic acid and formic acid are troublesome inhibitors restricting efficient microbial conversion of the biomass to desired products. To improve our understanding of weak acid inhibition and to identify engineering strategies to reduce acetic acid toxicity, the highly acetic‐acid‐tolerant yeast Zygosaccharomyces bailii was studied. The impact of acetic acid membrane permeability on acetic acid tolerance in Z. bailii was investigated with particular focus on how the previously demonstrated high sphingolipid content in the plasma membrane influences acetic acid tolerance and membrane permeability. Through molecular dynamics simulations, we concluded that membranes with a high content of sphingolipids are thicker and more dense, increasing the free energy barrier for the permeation of acetic acid through the membrane. Z. bailii cultured with the drug myriocin, known to decrease cellular sphingo­lipid levels, exhibited significant growth inhibition in the presence of acetic acid, while growth in medium without acetic acid was unaffected by the myriocin addition. Furthermore, following an acetic acid pulse, the intracellular pH decreased more in myriocin‐treated cells than in control cells. This indicates a higher inflow rate of acetic acid and confirms that the reduction in growth of cells cultured with myriocin in the medium with acetic acid was due to an increase in membrane permeability, thereby demonstrating the importance of a high fraction of sphingolipids in the membrane of Z. bailii to facilitate acetic acid resistance; a property potentially transferable to desired production organisms suffering from weak acid stress. Biotechnol. Bioeng. 2016;113: 744–753. © 2015 The Authors. Biotechnology and Bioengineering Published by Wiley Periodicals, Inc. PMID:26416641

  2. 1'-Acetoxychavicol acetate as an inhibitor of phagocytosis of macrophages.

    PubMed

    Watanabe, N; Kataoka, T; Tajika, T; Uramoto, M; Magae, J; Nagai, K

    1995-08-01

    We screened extracts of edible plants for inhibitors of phagocytosis by peritoneal exudate macrophages. 1'-Acetoxychavicol acetate was isolated from the ethyl acetate extract of Languas galanga, and this compound strongly inhibited phagocytosis at an IC50 value of 1.2 microM with negligible effects on pinocytosis and cell viability. Target(s) of 1'-acetoxychavicol acetate was suggested to be downstream of the signal transduction pathway that is mediated by protein kinase C.

  3. Stimulant Use Disorders.

    PubMed

    Park, Taryn M; Haning, William F

    2016-07-01

    Compared with other illicit substances, stimulants are not commonly used by adolescents; however, they represent a serious concern regarding substance use among youths. This article uses methamphetamine as a model for stimulant use in adolescents; cocaine and prescription stimulants are also mentioned. Methamphetamine use among adolescents and young adults is a serious health concern with potentially long-term physical, cognitive, and psychiatric consequences. Brain development and the effects of misusing stimulants align such that usage in adolescents can more dangerous than during adulthood. It seems helpful to keep in mind the differences between adolescents and young adults when implementing interventions. PMID:27338967

  4. Grape contribution to wine aroma: production of hexyl acetate, octyl acetate, and benzyl acetate during yeast fermentation is dependent upon precursors in the must.

    PubMed

    Dennis, Eric G; Keyzers, Robert A; Kalua, Curtis M; Maffei, Suzanne M; Nicholson, Emily L; Boss, Paul K

    2012-03-14

    Wine is a complex consumer product produced predominately by the action of yeast upon grape juice musts. Model must systems have proven ideal for studies of the effects of fermentation conditions on the production of certain wine volatiles. To identify grape-derived precursors to acetate esters, model fermentation systems were developed by spiking precursors into model must at different concentrations. Solid-phase microextraction-gas chromatgraphy mass spectrometry analysis of the fermented wines showed that a variety of grape-derived aliphatic alcohols and aldehydes are precursors to acetate esters. The C6 compounds hexan-1-ol, hexenal, (E)-2-hexen-1-ol, and (E)-2-hexenal are all precursors to hexyl acetate, and octanol and benzyl alcohol are precursors to octyl acetate and benzyl acetate, respectively. In these cases, the postfermentation concentration of an acetate ester increased proportionally with the prefermentation concentration of the respective precursor in the model must. Determining viticultural or winemaking methods to alter the prefermentation concentration of precursor compounds or change the precursor-to-acetate ester ratio will have implications upon the final flavor and aroma of wines. PMID:22332880

  5. Synthesis and regeneration of lead (IV) acetate

    SciTech Connect

    Boyle, T.J.; Al-Shareef, H.N.; Moore, G.J.

    1996-11-01

    Lead acetate [Pb(O{sub 2}CMe){sub 4}] was easily synthesized from a warm solution of Pb{sub 3}O{sub 4}, HO{sub 2}CMe and O(OCMe){sub 2} following literature preparations when the appropriate measures to minimize water contamination were followed. Furthermore, Pb(O{sub 2}CMe){sub 4} which has been decomposed (evidenced by the appearance of a purple color due to oxidation) can be regenerated using a similar preparatory route. Introduction of Pb(O{sub 2}CMe){sub 4} from the two routes outlined above into the IMO process for production of PZT thin films gave films with comparable ferroelectric properties to commercially available Pb(O{sub 2}CMe){sub 4} precursors. However, the freshly synthesized material yields PZT films with better properties compared to the recycled material.

  6. N-(2-Chloro-acet-yl)glycine.

    PubMed

    Zhang, Yu-Cheng; Zhang, Xiu-Qin; Wang, Kai; Chen, Qiang

    2013-10-26

    The title compound, C4H6ClNO3, crystallizes with two independent mol-ecules (A and B) in the asymmetric unit. In each mol-ecule, there are N-H⋯O and N-H⋯Cl hydrogen bonds. Both mol-ecules are relatively planar, with the mean plane of the acetamide [N-C(=O)C] group being inclined to the mean plane of the acetate group [C-C(=O)O] by 9.23 (13)° in mol-ecule A and 6.23 (12)° in mol-ecule B. In the crystal, adjacent mol-ecules are linked by O-H⋯O hydrogen bonds and weak C-H⋯O contacts forming -A-A-A- and -B-B-B- parallel chains propagating along the a-axis direction. PMID:24454136

  7. Unsuccessful treatment of acromegaly with medroxyprogesterone acetate.

    PubMed

    Atkinson, R L; Dimond, R C; Howard, W J; Earll, J M

    1974-09-01

    6 patients with active acromegaly were treated with 10 mg of medroxyprogesterone acetate (MPA) every 6 hours daily for 2 weeks to 6 months. Oral glucose tolerance tests, growth hormone (GH) levels, and insulin tolerance tests (ITT) were done before and during MPA treatment. Basal GH levels varied widely during control and therapy periods; no significant lowering of GH levels occurred during treatment. Carbohydrate tolerance was not significantly affected by MPA therapy, although 5 out of 6 patients had deterioration at least once during treatment. Blood glucose response to ITT was unchanged by MPA. MPA did not affect the clinical features of acromegaly. There was no consistent effect of MPA on insulin-induced or arginine-induced GH secretion. It is concluded that MPA is not an effective agent for treating acromegaly.

  8. Oxidation of indole-3-acetic acid to oxindole-3-acetic acid by an enzyme preparation from Zea mays

    NASA Technical Reports Server (NTRS)

    Reinecke, D. M.; Bandurski, R. S.

    1988-01-01

    Indole-3-acetic acid is oxidized to oxindole-3-acetic acid by Zea mays tissue extracts. Shoot, root, and endosperm tissues have enzyme activities of 1 to 10 picomoles per hour per milligram protein. The enzyme is heat labile, is soluble, and requires oxygen for activity. Cofactors of mixed function oxygenase, peroxidase, and intermolecular dioxygenase are not stimulatory to enzymic activity. A heat-stable, detergent-extractable component from corn enhances enzyme activity 6- to 10-fold. This is the first demonstration of the in vitro enzymic oxidation of indole-3-acetic acid to oxindole-3-acetic acid in higher plants.

  9. [Electromagnetic urological stimulator].

    PubMed

    Zaslavskiĭ AOi; Markarov, G S; Gelis, Iu S

    1997-01-01

    The paper deals with an electromagnetic urological stimulator which generates a modulated low-frequency electromagnetic field of nonthermal intensity and its brief technical data. It presents a treatment regimen for urolithiasis and recommendations how to use the above therapeutical agent to stimulate urinary function in patients with urolithiasis in order to inoperatively eliminate urinary calculi and sand which form following extracorporeal shockwave lithotripsy.

  10. Stimulating your appetite.

    PubMed

    Whitfield, L

    1998-01-01

    A number of legal and illegal drugs can help stimulate appetite and are used for people with HIV to prevent wasting. Stimulating hunger is important because lower calorie intake and poor absorption of nutrients are associated with wasting. The uses and potential drawbacks of marijuana, thalidomide (Synovir), Marinol, and Megace are described. PMID:11365223

  11. A double-blind placebo controlled trial of medroxyprogesterone acetate and cyproterone acetate with seven pedophiles.

    PubMed

    Cooper, A J; Sandhu, S; Losztyn, S; Cernovsky, Z

    1992-12-01

    Seven of ten pedophiles in hospital completed a double-blind, placebo-controlled two-dose comparison of medroxyprogesterone acetate and cyproterone acetate. Sequential measures during the 28 week study were: patient self-reports, nurses' observations, phallometry, hormone levels and side-effects. The drugs, which performed equivalently, reduced sexual thoughts and fantasies, the frequency of early morning erections on awakening, the frequency and pleasure of masturbation, and level of sexual frustration. Penile responses were also reduced but to a lesser degree and were more variable. Serum testosterone FSH and LH all declined during drug administration, but by the end of the final placebo phase had essentially returned to (or exceeded) pre-drug values. Our experience suggests that only a minority of pedophiles are likely to accept libido-reducing drugs.

  12. Heterogeneous catalyst for the production of acetic anhydride from methyl acetate

    SciTech Connect

    Ramprasad, Dorai; Waller, Francis Joseph

    1999-01-01

    This invention relates to a process for producing acetic anhydride by the reaction of methyl acetate, carbon monoxide, and hydrogen at elevated temperatures and pressures in the presence of an alkyl halide and a heterogeneous, bifunctional catalyst that contains an insoluble polymer having pendant quaternized phosphine groups, some of which phosphine groups are ionically bonded to anionic Group VIII metal complexes, the remainder of the phosphine groups being bonded to iodide. In contrast to prior art processes, no accelerator (promoter) is necessary to achieve the catalytic reaction and the products are easily separated from the catalyst by filtration. The catalyst can be recycled for consecutive runs without loss in activity. Bifunctional catalysts for use in carbonylating dimethyl ether are also provided.

  13. Heterogeneous catalyst for the production of acetic anhydride from methyl acetate

    SciTech Connect

    Ramprasad, D.; Waller, F.J.

    1999-04-06

    This invention relates to a process for producing acetic anhydride by the reaction of methyl acetate, carbon monoxide, and hydrogen at elevated temperatures and pressures in the presence of an alkyl halide and a heterogeneous, bifunctional catalyst that contains an insoluble polymer having pendant quaternized phosphine groups, some of which phosphine groups are ionically bonded to anionic Group VIII metal complexes, the remainder of the phosphine groups being bonded to iodide. In contrast to prior art processes, no accelerator (promoter) is necessary to achieve the catalytic reaction and the products are easily separated from the catalyst by filtration. The catalyst can be recycled for consecutive runs without loss in activity. Bifunctional catalysts for use in carbonylating dimethyl ether are also provided.

  14. Nomegestrol acetate/estradiol hormonal oral contraceptive and breast cancer risk.

    PubMed

    Del Pup, Lino; Berretta, Massimiliano; Di Francia, Raffaele; Cavaliere, Carla; Di Napoli, Marilena; Facchini, Gaetano; Fiorica, Francesco; Mileto, Mario; Schindler, Adolf E

    2014-08-01

    Combined hormonal contraceptives (CHCs) contain estrogen and progestin, which can stimulate estrogen-sensitive and/or progesterone-sensitive breast cancer growth. Until recently, ethinylestradiol had been almost the only estrogen used for decades, and its dose has been greatly reduced over time. The first generations of birth control pills contained approximately five times more estrogen and four times more progestin than the latest contraceptives. Newer CHCs also contain steroids that more closely mimic the physiological estradiol (E2) and progesterone effects. The newer CHC formulations are thus expected to have less influence on the breast, although it is very difficult to demonstrate any difference among the recent available preparations in human studies. Recently, nomegestrol acetate (NOMAC), a neutral, nonandrogenic, progesterone-like profile progestin, has become available in combination with the 'natural' estrogen, E2. According to the literature, NOMAC/E2 is expected to have either a lesser stimulating effect or a neutral effect on estrogen-sensitive breast cancers. We performed an analysis of the available studies and a bibliographical review. The endocrine and metabolic effects of NOMAC/E2 formulation might lead to a lesser breast tissue stimulation. The data reported, confirmed through clinical studies, should be considered when choosing a hormonal contraceptive, especially when breast stimulation is a concern.

  15. Three manganese oxide-rich marine sediments harbor similar communities of acetate-oxidizing manganese-reducing bacteria.

    PubMed

    Vandieken, Verona; Pester, Michael; Finke, Niko; Hyun, Jung-Ho; Friedrich, Michael W; Loy, Alexander; Thamdrup, Bo

    2012-11-01

    Dissimilatory manganese reduction dominates anaerobic carbon oxidation in marine sediments with high manganese oxide concentrations, but the microorganisms responsible for this process are largely unknown. In this study, the acetate-utilizing manganese-reducing microbiota in geographically well-separated, manganese oxide-rich sediments from Gullmar Fjord (Sweden), Skagerrak (Norway) and Ulleung Basin (Korea) were analyzed by 16S rRNA-stable isotope probing (SIP). Manganese reduction was the prevailing terminal electron-accepting process in anoxic incubations of surface sediments, and even the addition of acetate stimulated neither iron nor sulfate reduction. The three geographically distinct sediments harbored surprisingly similar communities of acetate-utilizing manganese-reducing bacteria: 16S rRNA of members of the genera Colwellia and Arcobacter and of novel genera within the Oceanospirillaceae and Alteromonadales were detected in heavy RNA-SIP fractions from these three sediments. Most probable number (MPN) analysis yielded up to 10(6) acetate-utilizing manganese-reducing cells cm(-3) in Gullmar Fjord sediment. A 16S rRNA gene clone library that was established from the highest MPN dilutions was dominated by sequences of Colwellia and Arcobacter species and members of the Oceanospirillaceae, supporting the obtained RNA-SIP results. In conclusion, these findings strongly suggest that (i) acetate-dependent manganese reduction in manganese oxide-rich sediments is catalyzed by members of taxa (Arcobacter, Colwellia and Oceanospirillaceae) previously not known to possess this physiological function, (ii) similar acetate-utilizing manganese reducers thrive in geographically distinct regions and (iii) the identified manganese reducers differ greatly from the extensively explored iron reducers in marine sediments. PMID:22572639

  16. Chemistry of Ketene N,S-Acetals: An Overview.

    PubMed

    Zhang, Lin; Dong, Jinhuan; Xu, Xianxiu; Liu, Qun

    2016-01-27

    Push-pull alkenes, which bear electron-donating and -accepting group(s) at both termini of a C═C double bond, respectively, are of interest not only for their unique electronic properties but also for their importance as versatile building blocks in organic synthesis. In the world of ketene acetals having the push-pull alkene skeleton, ketene N,S-acetal is most likely the biggest family according to the number and types of these compounds. The first ketene N,S-acetal compound was reported in 1956. As a cyclic ketene N,S-acetal compound, nithiazine, the first lead structure of neonicotinoid insecticides, was reported in 1978. The characteristics of ketene N,S-acetals, which have the structural feature of ketene S,S-acetals and enaminones, make them versatile and easy to use, especially in cyclization and multicomponent reactions for the synthesis of various heterocyclic systems and related natural products. There has been an increasing wealth of information about the synthesis and synthetic applications of ketene N,S-acetals, especially, in recent years. This review provides comprehensive knowledge on the chemistry of ketene N,S-acetals. PMID:26760899

  17. 21 CFR 522.960b - Flumethasone acetate injection.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Flumethasone acetate injection. 522.960b Section 522.960b Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.960b Flumethasone acetate injection....

  18. Trehalose accumulation enhances tolerance of Saccharomyces cerevisiae to acetic acid.

    PubMed

    Yoshiyama, Yoko; Tanaka, Koichi; Yoshiyama, Kohei; Hibi, Makoto; Ogawa, Jun; Shima, Jun

    2015-02-01

    Trehalose confers protection against various environmental stresses on yeast cells. In this study, trehalase gene deletion mutants that accumulate trehalose at high levels showed significant stress tolerance to acetic acid. The enhancement of trehalose accumulation can thus be considered a target in the breeding of acetic acid-tolerant yeast strains.

  19. Transition-Metal-Catalyzed Carbonylation of Methyl Acetate.

    ERIC Educational Resources Information Center

    Polichnowski, S. W.

    1986-01-01

    Presents a study of the rhodium-catalyzed, ioding-promoted carbonylation of methyl acetate. This study provides an interesting contrast between the carbonylation of methyl acetate and the carbonylation of methanol when similar rhodium/iodine catalyst systems are used. (JN)

  20. Treatment of a malignant enterocutaneous fistula with octreotide acetate.

    PubMed

    Ayache, S; Wadleigh, R G

    1999-01-01

    An enterocutaneous malignant fistula developed in a patient who had a retroperitoneal angiosarcoma. He was treated with octreotide acetate subcutaneously. Drainage decreased and ceased after 2 weeks of therapy. The closure of this malignant fistula suggests that palliative therapy with octreotide acetate merits further study in view of the grave prognosis of this complication.

  1. Enrichment of amino acid-oxidizing, acetate-reducing bacteria.

    PubMed

    Ato, Makoto; Ishii, Masaharu; Igarashi, Yasuo

    2014-08-01

    In anaerobic condition, amino acids are oxidatively deaminated, and decarboxylated, resulting in the production of volatile fatty acids. In this process, excess electrons are produced and their consumption is necessary for the accomplishment of amino acid degradation. In this study, we anaerobically constructed leucine-degrading enrichment cultures from three different environmental samples (compost, excess sludge, and rice field soil) in order to investigate the diversity of electron-consuming reaction coupled to amino acid oxidation. Constructed enrichment cultures oxidized leucine to isovalerate and their activities were strongly dependent on acetate. Analysis of volatile fatty acids (VFAs) profiles and community structure analysis during batch culture of each enrichment indicated that Clostridium cluster I coupled leucine oxidation to acetate reduction in the enrichment from the compost and the rice field soil. In these cases, acetate was reduced to butyrate. On the other hand, Clostridium cluster XIVb coupled leucine oxidation to acetate reduction in the enrichment from the excess sludge. In this case, acetate was reduced to propionate. To our surprise, the enrichment from rice field soil oxidized leucine even in the absence of acetate and produced butyrate. The enrichment would couple leucine oxidation to reductive butyrate synthesis from CO2. The coupling reaction would be achieved based on trophic link between hydrogenotrophic acetogenic bacteria and acetate-reducing bacteria by sequential reduction of CO2 and acetate. Our study suggests anaerobic degradation of amino acids is achieved yet-to-be described reactions. PMID:24630616

  2. 40 CFR 721.303 - Substituted acetate (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.303 Substituted acetate (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted acetate (PMN...

  3. 40 CFR 721.303 - Substituted acetate (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.303 Substituted acetate (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted acetate (PMN...

  4. Cooperation of electrically stimulated muscle and pneumatic muscle to realize RUPERT bi-directional motion for grasping.

    PubMed

    Xikai Tu; Jiping He; Yue Wen; Jian Huang; Xinhan Huang; Hailong Huang; Meng Guo; Yong Yuan

    2014-01-01

    Robot-assisted rehabilitation is an active area of research to meet the demand of repetitive therapy in stroke rehabilitation. Robotic upper-extremity repetitive trainer (RUPERT) with its unidirectional pneumatic muscle actuation (PMA) can be used by most stroke patients that have difficulty moving in one direction because of a weak agonist or hyperactive antagonist. In this research, to broaden the usage of RUPERT, we not only add grasping functionality to the rehabilitation robot with the help of surface Functional Electrical Stimulation (FES) but also realize the robot joint bi-directional motion by using a PMA in cooperation with surface FES evoked paralyzed muscle force. This integrative rehabilitation strategy is explored for training patients to practice coordinated reaching and grasping functions. The effectiveness of this FES electrically evoked bio-actuator way is verified through a method that separates the mixed electromyogram (MEMG) into the electrically evoked electromyogram (EEMG) and voluntary electromyogram (VEMG). This is a promising approach to alleviate the size and mechanical complexity of the robot, thereby the cost of the joint bi-directional actuator rehabilitation robot by means of their own characteristics of stroke subjects.

  5. Delineation of myocardial oxygen utilization with carbon-11-labeled acetate

    SciTech Connect

    Brown, M.; Marshall, D.R.; Sobel, B.E.; Bergmann, S.R.

    1987-09-01

    Although positron-emission tomography (PET) with labeled fatty acid delineates infarct size and permits qualitative assessment of fatty acid utilization, quantification of oxidative metabolism is limited by complex alterations in the pattern of utilization of fatty acid during ischemia and reperfusion. Because metabolism of acetate by myocardium is less complex than that of glucose or palmitate, we characterized kinetics of utilization of radiolabeled acetate in 37 isolated rabbit hearts perfused with modified Krebs-Henseleit buffer and performed a pilot tomographic study in man. Results of initial experiments with carbon-14-labeled acetate (/sup 14/C-acetate) indicated that the steady-state extraction fraction of acetate averaged 61.5 +/- 4.0% in control hearts (n = 4), 93.6 +/- 0.9% in hearts rendered ischemic (n = 4), and 54.8 +/- 4.0% in hearts reperfused after 60 min of ischemia (n = 3). Oxidation of /sup 14/C-acetate, assessed from the rate of efflux of /sup 14/CO/sub 2/ in the venous effluent, correlated closely with the rate of oxygen consumption under diverse metabolic conditions (r = .97, p less than .001). In addition, no significant differences were observed between rates of efflux of total /sup 14/C in all chemical species (reflecting total clearance of tracer from myocardium) and efflux of /sup 14/CO/sub 2/. Clearance of /sup 11/C-acetate, measured externally with gamma probes in normal and ischemic myocardium, correlated closely with clearance of /sup 14/C-acetate measured directly in the effluent (r = .99, p less than .001) and with overall myocardial oxygen consumption (r = .95, p less than .001). Accumulation and clearance of /sup 11/C-acetate from human myocardium with PET demonstrated kinetics comparable to those seen with radiolabeled acetate in vitro.

  6. Fermentation of lignocellulosic sugars to acetic acid by Moorella thermoacetica.

    PubMed

    Ehsanipour, Mandana; Suko, Azra Vajzovic; Bura, Renata

    2016-06-01

    A systematic study of bioconversion of lignocellulosic sugars to acetic acid by Moorella thermoacetica (strain ATCC 39073) was conducted. Four different water-soluble fractions (hydrolysates) obtained after steam pretreatment of lignocellulosic biomass were selected and fermented to acetic acid in batch fermentations. M. thermoacetica can effectively ferment xylose and glucose in hydrolysates from wheat straw, forest residues, switchgrass, and sugarcane straw to acetic acid. Xylose and glucose were completely utilized, with xylose being consumed first. M. thermoacetica consumed up to 62 % of arabinose, 49 % galactose and 66 % of mannose within 72 h of fermentation in the mixture of lignocellulosic sugars. The highest acetic acid yield was obtained from sugarcane straw hydrolysate, with 71 % of theoretical yield based on total sugars (17 g/L acetic acid from 24 g/L total sugars). The lowest acetic acid yield was observed in forest residues hydrolysate, with 39 % of theoretical yield based on total sugars (18 g/L acetic acid from 49 g/L total sugars). Process derived compounds from steam explosion pretreatment, including 5-hydroxymethylfurfural (0.4 g/L), furfural (0.1 g/L) and total phenolics (3 g/L), did not inhibit microbial growth and acetic acid production yield. This research identified two major factors that adversely affected acetic acid yield in all hydrolysates, especially in forest residues: (i) glucose to xylose ratio and (ii) incomplete consumption of arabinose, galactose and mannose. For efficient bioconversion of lignocellulosic sugars to acetic acid, it is imperative to have an appropriate balance of sugars in a hydrolysate. Hence, the choice of lignocellulosic biomass and steam pretreatment design are fundamental steps for the industrial application of this process.

  7. Fermentation of lignocellulosic sugars to acetic acid by Moorella thermoacetica.

    PubMed

    Ehsanipour, Mandana; Suko, Azra Vajzovic; Bura, Renata

    2016-06-01

    A systematic study of bioconversion of lignocellulosic sugars to acetic acid by Moorella thermoacetica (strain ATCC 39073) was conducted. Four different water-soluble fractions (hydrolysates) obtained after steam pretreatment of lignocellulosic biomass were selected and fermented to acetic acid in batch fermentations. M. thermoacetica can effectively ferment xylose and glucose in hydrolysates from wheat straw, forest residues, switchgrass, and sugarcane straw to acetic acid. Xylose and glucose were completely utilized, with xylose being consumed first. M. thermoacetica consumed up to 62 % of arabinose, 49 % galactose and 66 % of mannose within 72 h of fermentation in the mixture of lignocellulosic sugars. The highest acetic acid yield was obtained from sugarcane straw hydrolysate, with 71 % of theoretical yield based on total sugars (17 g/L acetic acid from 24 g/L total sugars). The lowest acetic acid yield was observed in forest residues hydrolysate, with 39 % of theoretical yield based on total sugars (18 g/L acetic acid from 49 g/L total sugars). Process derived compounds from steam explosion pretreatment, including 5-hydroxymethylfurfural (0.4 g/L), furfural (0.1 g/L) and total phenolics (3 g/L), did not inhibit microbial growth and acetic acid production yield. This research identified two major factors that adversely affected acetic acid yield in all hydrolysates, especially in forest residues: (i) glucose to xylose ratio and (ii) incomplete consumption of arabinose, galactose and mannose. For efficient bioconversion of lignocellulosic sugars to acetic acid, it is imperative to have an appropriate balance of sugars in a hydrolysate. Hence, the choice of lignocellulosic biomass and steam pretreatment design are fundamental steps for the industrial application of this process. PMID:26992903

  8. Morphological diversity of Blastocystis hominis in sodium acetate-acetic acid-formalin-preserved stool samples stained with iron hematoxylin.

    PubMed

    MacPherson, D W; MacQueen, W M

    1994-01-01

    The objective of this investigation was to study the morphological characteristics of Blastocystis hominis in sodium acetate-acetic acid-Formalin-preserved stool samples. Routinely processed samples were examined for morphological detail, including size, shape, nuclear detail, and central body characteristics. Morphological findings revealing the importance of recognizing B. hominis in the diagnostic laboratory are described. PMID:7510311

  9. Gas-Phase Structures of Ketene and Acetic Acid from Acetic Anhydride Using Very-High-Temperature Gas Electron Diffraction.

    PubMed

    Atkinson, Sandra J; Noble-Eddy, Robert; Masters, Sarah L

    2016-03-31

    The gas-phase molecular structure of ketene has been determined using samples generated by the pyrolysis of acetic anhydride (giving acetic acid and ketene), using one permutation of the very-high-temperature (VHT) inlet nozzle system designed and constructed for the gas electron diffraction (GED) apparatus based at the University of Canterbury. The gas-phase structures of acetic anhydride, acetic acid, and ketene are presented and compared to previous electron diffraction and microwave spectroscopy data to show improvements in data extraction and manipulation with current methods. Acetic anhydride was modeled with two conformers, rather than a complex dynamic model as in the previous study, to allow for inclusion of multiple pyrolysis products. The redetermined gas-phase structure of acetic anhydride (obtained using the structure analysis restrained by ab initio calculations for electron diffraction method) was compared to that from the original study, providing an improvement on the description of the low vibrational torsions compared to the dynamic model. Parameters for ketene and acetic acid (both generated by the pyrolysis of acetic anhydride) were also refined with higher accuracy than previously reported in GED studies, with structural parameter comparisons being made to prior experimental and theoretical studies. PMID:26916368

  10. Measurement of the rates of oxindole-3-acetic acid turnover, and indole-3-acetic acid oxidation in Zea mays seedlings

    NASA Technical Reports Server (NTRS)

    Nonhebel, H. M.; Bandurski, R. S. (Principal Investigator)

    1986-01-01

    Oxindole-3-acetic acid is the principal catabolite of indole-3-acetic acid in Zea mays seedlings. In this paper measurements of the turnover of oxindole-3-acetic acid are presented and used to calculate the rate of indole-3-acetic acid oxidation. [3H]Oxindole-3-acetic acid was applied to the endosperm of Zea mays seedlings and allowed to equilibrate for 24 h before the start of the experiment. The subsequent decrease in its specific activity was used to calculate the turnover rate. The average half-life of oxindole-3-acetic acid in the shoots was found to be 30 h while that in the kernels had an average half-life of 35h. Using previously published values of the pool sizes of oxindole-3-acetic acid in shoots and kernels from seedlings of the same age and variety, and grown under the same conditions, the rate of indole-3-acetic acid oxidation was calculated to be 1.1 pmol plant-1 h-1 in the shoots and 7.1 pmol plant-1 h-1 in the kernels.

  11. Biological Function of Acetic Acid-Improvement in Obesity and Glucose Tolerance by Acetic Acid in Type 2 Diabetic Rats.

    PubMed

    Yamashita, Hiromi

    2016-07-29

    Fatty acids derived from adipose tissue are oxidized by β-oxidation to form ketone bodies as final products under the starving condition. Previously, we found that free acetic acid was formed concomitantly with the production of ketone bodies in isolated rat liver perfusion, and mitochondrial acetyl CoA hydrolase was appeared to be involved with the acetic acid production. It was revealed that acetic acid was formed as a final product of enhanced β-oxidation of fatty acids and utilized as a fuel in extrahepatic tissues under the starving condition. Under the fed condition, β-oxidation is suppressed and acetic acid production is decreased. When acetic acid was taken daily by obesity-linked type 2 diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats under the fed condition, it protected OLETF rats against obesity. Furthermore, acetic acid contributed to protect from the accumulation of lipid in the liver as well as abdominal fat in OLETF rats. Transcripts of lipogenic genes in the liver were decreased, while transcripts of myoglobin and Glut4 genes in abdominal muscles were increased in the acetic acid-administered OLETF rats. It is indicated that exogenously administered acetic acid would have effects on lipid metabolism in both the liver and the skeletal muscles, and have function that works against obesity and obesity-linked type 2 diabetes.

  12. Gas-Phase Structures of Ketene and Acetic Acid from Acetic Anhydride Using Very-High-Temperature Gas Electron Diffraction.

    PubMed

    Atkinson, Sandra J; Noble-Eddy, Robert; Masters, Sarah L

    2016-03-31

    The gas-phase molecular structure of ketene has been determined using samples generated by the pyrolysis of acetic anhydride (giving acetic acid and ketene), using one permutation of the very-high-temperature (VHT) inlet nozzle system designed and constructed for the gas electron diffraction (GED) apparatus based at the University of Canterbury. The gas-phase structures of acetic anhydride, acetic acid, and ketene are presented and compared to previous electron diffraction and microwave spectroscopy data to show improvements in data extraction and manipulation with current methods. Acetic anhydride was modeled with two conformers, rather than a complex dynamic model as in the previous study, to allow for inclusion of multiple pyrolysis products. The redetermined gas-phase structure of acetic anhydride (obtained using the structure analysis restrained by ab initio calculations for electron diffraction method) was compared to that from the original study, providing an improvement on the description of the low vibrational torsions compared to the dynamic model. Parameters for ketene and acetic acid (both generated by the pyrolysis of acetic anhydride) were also refined with higher accuracy than previously reported in GED studies, with structural parameter comparisons being made to prior experimental and theoretical studies.

  13. Effects of acetate, propionate, and butyrate on the thermophilic anaerobic degradation of propionate by methanogenic sludge and defined cultures

    SciTech Connect

    Lier, J.B. van; Grolle, K.C.F.; Frijters, C.T.M.J.; Stams, A.J.M.; Lettinga, G. )

    1993-04-01

    Acetate, propionate, and butyrate are intermediate products in the anaerobic bioconversion of organic matter to methane and carbon dioxide. This study examines the effects of acetate, propionate, and butyrate on the thermophilic oxidation of propionate in continuous-flow methanogenic sludge bed systems and in defined propionate-oxidizing cultures. Volatile fatty acids (VFA) in sludge inhibit thermophilic anaerobic oxidation of propionate, dependent on the concentration and on the pH. Addition of butyrate-oxidizing acetogens to the media eliminate the inhibitory effect of butyrate and stimulated propionate conversion. In the propionate-oxidizing enrichment, and to a lesser extent in the UASB reactor, culture growth was affected by acetate. However, the relationship between acetate concentrations and propionate degradation was not clear. Hydrogen is an important intermediate of thermophilic propionate conversion. This study found that propionate oxidation was severely inhibited with no increase in the hydrogen partial pressure in the biogas. As a result, the authors conclude the suitability of hydrogen as a n overall control parameter for anaerobic digestion has to be reconsidered. 29 refs., 6 figs., 2 tabs.

  14. Nematocyst discharge in Pelagia noctiluca (Cnidaria, Scyphozoa) oral arms can be affected by lidocaine, ethanol, ammonia and acetic acid.

    PubMed

    Morabito, Rossana; Marino, Angela; Dossena, Silvia; La Spada, Giuseppa

    2014-06-01

    Nematocyst discharge and concomitant delivery of toxins is triggered to perform both defence and predation strategies in Cnidarians, and may lead to serious local and systemic reactions in humans. Pelagia noctiluca (Cnidaria, Scyphozoa) is a jellyfish particularly abundant in the Strait of Messina (Italy). After accidental contact with this jellyfish, not discharged nematocysts or even fragments of tentacles or oral arms may tightly adhere to the human skin and, following discharge, severely increase pain and the other adverse consequences of the sting. The aim of the present study is to verify if the local anesthetic lidocaine and other compounds, like alcohols, acetic acid and ammonia, known to provide pain relief after jellyfish stings, may also affect in situ discharge of nematocysts. Discharge was induced by a combined physico-chemical stimulation of oral arms by chemosensitizers (such as N-acetylated sugars, aminoacids, proteins and nucleotides), in the presence or absence of 1% lidocaine, 70% ethanol, 5% acetic acid or 20% ammonia, followed by mechanical stimulation by a non-vibrating test probe. The above mentioned compounds failed to induce discharge per se, and dramatically impaired the chemosensitizer-induced discharge response. We therefore suggest that prompt local treatment of the stung epidermis with lidocaine, acetic acid, ethanol and ammonia may provide substantial pain relief and help in reducing possible harmful local and systemic adverse reaction following accidental contact with P. noctiluca specimens.

  15. Oxidation of indole-3-acetic acid and oxindole-3-acetic acid to 2,3-dihydro-7-hydroxy-2-oxo-1H indole-3-acetic acid-7'-O-beta-D-glucopyranoside in Zea mays seedlings

    NASA Technical Reports Server (NTRS)

    Nonhebel, H. M.; Bandurski, R. S.

    1984-01-01

    Radiolabeled oxindole-3-acetic acid was metabolized by roots, shoots, and caryopses of dark grown Zea mays seedlings to 2,3-dihydro-7-hydroxy-2-oxo-1H indole-3-acetic acid-7'-O-beta-D-glycopyranoside with the simpler name of 7-hydroxyoxindole-3-acetic acid-glucoside. This compound was also formed from labeled indole-3-acetic acid supplied to intact seedlings and root segments. The glucoside of 7-hydroxyoxindole-3-acetic acid was also isolated as an endogenous compound in the caryopses and shoots of 4-day-old seedlings. It accumulates to a level of 4.8 nanomoles per plant in the kernel, more than 10 times the amount of oxindole-3-acetic acid. In the shoot it is present at levels comparable to that of oxindole-3-acetic acid and indole-3-acetic acid (62 picomoles per shoot). We conclude that 7-hydroxyoxindole-3-acetic acid-glucoside is a natural metabolite of indole-3-acetic acid in Z. mays seedlings. From the data presented in this paper and in previous work, we propose the following route as the principal catabolic pathway for indole-3-acetic acid in Zea seedlings: Indole-3-acetic acid --> Oxindole-3-acetic acid --> 7-Hydroxyoxindole-3-acetic acid --> 7-Hydroxyoxindole-3-acetic acid-glucoside.

  16. Quantitative Structure of an Acetate Dye Molecule Analogue at the TiO2–Acetic Acid Interface

    PubMed Central

    2016-01-01

    The positions of atoms in and around acetate molecules at the rutile TiO2(110) interface with 0.1 M acetic acid have been determined with a precision of ±0.05 Å. Acetate is used as a surrogate for the carboxylate groups typically employed to anchor monocarboxylate dye molecules to TiO2 in dye-sensitized solar cells (DSSC). Structural analysis reveals small domains of ordered (2 × 1) acetate molecules, with substrate atoms closer to their bulk terminated positions compared to the clean UHV surface. Acetate is found in a bidentate bridge position, binding through both oxygen atoms to two 5-fold titanium atoms such that the molecular plane is along the [001] azimuth. Density functional theory calculations provide adsorption geometries in excellent agreement with experiment. The availability of these structural data will improve the accuracy of charge transport models for DSSC. PMID:27110318

  17. Optically stimulated luminescence dosimetry

    NASA Astrophysics Data System (ADS)

    McKeever, Stephen W. S.

    2001-09-01

    Models and the conceptual framework necessary for an understanding of optically stimulated luminescence (OSL) are described. Examples of various OSL readout schemes are described, along with examples of the use of OSL in radiation dosimetry.

  18. Deep brain stimulation

    MedlinePlus

    ... the brain The neurostimulator, which puts out the electric current. The stimulator is similar to a heart pacemaker . It is usually placed under the skin near the collarbone, but may be ... pulses travel from the neurostimulator, along the extension ...

  19. ACTH stimulation test

    MedlinePlus

    ... Groot LJ, de Kretser DM, et al, eds. Endocrinology: Adult and Pediatric . 7th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 102. Chernecky CC, Berger BJ. ACTH stimulation test - diagnostic. In: ... . 13th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap ...

  20. Geothermal Well Stimulation

    SciTech Connect

    Campbell, D. A.; Morris, C. W.; Sinclair, A. R.; Hanold, R. J.; Vetter, O. J.

    1981-03-01

    The stimulation of geothermal wells presents some new and challenging problems. Formation temperatures in the 300-600 F range can be expected. The behavior of stimulation fluids, frac proppants, and equipment at these temperatures in a hostile brine environment must be carefully evaluated before performance expectations can be determined. In order to avoid possible damage to the producing horizon of the formation, high temperature chemical compatibility between the in situ materials and the stimulation materials must be verified. Perhaps most significant of all, in geothermal wells the required techniques must be capable of bringing about the production of very large amounts of fluid. This necessity for high flow rates represents a significant departure from conventional petroleum well stimulation and demands the creation of very high near-wellbore permeability and/or fractures with very high flow conductivity.

  1. Simultaneous production of acetic and gluconic acids by a thermotolerant Acetobacter strain during acetous fermentation in a bioreactor.

    PubMed

    Mounir, Majid; Shafiei, Rasoul; Zarmehrkhorshid, Raziyeh; Hamouda, Allal; Ismaili Alaoui, Mustapha; Thonart, Philippe

    2016-02-01

    The activity of bacterial strains significantly influences the quality and the taste of vinegar. Previous studies of acetic acid bacteria have primarily focused on the ability of bacterial strains to produce high amounts of acetic acid. However, few studies have examined the production of gluconic acid during acetous fermentation at high temperatures. The production of vinegar at high temperatures by two strains of acetic acid bacteria isolated from apple and cactus fruits, namely AF01 and CV01, respectively, was evaluated in this study. The simultaneous production of gluconic and acetic acids was also examined in this study. Biochemical and molecular identification based on a 16s rDNA sequence analysis confirmed that these strains can be classified as Acetobacter pasteurianus. To assess the ability of the isolated strains to grow and produce acetic acid and gluconic acid at high temperatures, a semi-continuous fermentation was performed in a 20-L bioreactor. The two strains abundantly grew at a high temperature (41°C). At the end of the fermentation, the AF01 and CV01 strains yielded acetic acid concentrations of 7.64% (w/v) and 10.08% (w/v), respectively. Interestingly, CV01 was able to simultaneously produce acetic and gluconic acids during acetic fermentation, whereas AF01 mainly produced acetic acid. In addition, CV01 was less sensitive to ethanol depletion during semi-continuous fermentation. Finally, the enzymatic study showed that the two strains exhibited high ADH and ALDH enzyme activity at 38°C compared with the mesophilic reference strain LMG 1632, which was significantly susceptible to thermal inactivation. PMID:26253254

  2. Simultaneous production of acetic and gluconic acids by a thermotolerant Acetobacter strain during acetous fermentation in a bioreactor.

    PubMed

    Mounir, Majid; Shafiei, Rasoul; Zarmehrkhorshid, Raziyeh; Hamouda, Allal; Ismaili Alaoui, Mustapha; Thonart, Philippe

    2016-02-01

    The activity of bacterial strains significantly influences the quality and the taste of vinegar. Previous studies of acetic acid bacteria have primarily focused on the ability of bacterial strains to produce high amounts of acetic acid. However, few studies have examined the production of gluconic acid during acetous fermentation at high temperatures. The production of vinegar at high temperatures by two strains of acetic acid bacteria isolated from apple and cactus fruits, namely AF01 and CV01, respectively, was evaluated in this study. The simultaneous production of gluconic and acetic acids was also examined in this study. Biochemical and molecular identification based on a 16s rDNA sequence analysis confirmed that these strains can be classified as Acetobacter pasteurianus. To assess the ability of the isolated strains to grow and produce acetic acid and gluconic acid at high temperatures, a semi-continuous fermentation was performed in a 20-L bioreactor. The two strains abundantly grew at a high temperature (41°C). At the end of the fermentation, the AF01 and CV01 strains yielded acetic acid concentrations of 7.64% (w/v) and 10.08% (w/v), respectively. Interestingly, CV01 was able to simultaneously produce acetic and gluconic acids during acetic fermentation, whereas AF01 mainly produced acetic acid. In addition, CV01 was less sensitive to ethanol depletion during semi-continuous fermentation. Finally, the enzymatic study showed that the two strains exhibited high ADH and ALDH enzyme activity at 38°C compared with the mesophilic reference strain LMG 1632, which was significantly susceptible to thermal inactivation.

  3. The Effects of Acetate Buffer Concentration on Lysozyme Solubility

    NASA Technical Reports Server (NTRS)

    Forsythe, Elizabeth L.; Pusey, Marc L.

    1996-01-01

    The micro-solubility column technique was employed to systematically investigate the effects of buffer concentration on tetragonal lysozyme solubility. While keeping the NaCl concentrations constant at 2%, 3%, 4%, 5% and 7%, and the pH at 4.0, we have studied the solubility of tetragonal lysozyme over an acetate buffer concentration range of 0.01M to 0.5M as a function of temperature. The lysozyme solubility decreased with increasing acetate concentration from 0.01M to 0.1M. This decrease may simply be due to the net increase in solvent ionic strength. Increasing the acetate concentration beyond 0.1M resulted in an increase in the lysozyme solubility, which reached a peak at - 0.3M acetate concentration. This increase was believed to be due to the increased binding of acetate to the anionic binding sites of lysozyme, preventing their occupation by chloride. In keeping with the previously observed reversal of the Hoffmeister series for effectiveness of anions in crystallizing lysozyme, acetate would be a less effective precipitant than chloride. Further increasing the acetate concentration beyond 0.3M resulted in a subsequent gradual decrease in the lysozyme solubility at all NaCl concentrations.

  4. Computerized image analysis for acetic acid induced intraepithelial lesions

    NASA Astrophysics Data System (ADS)

    Li, Wenjing; Ferris, Daron G.; Lieberman, Rich W.

    2008-03-01

    Cervical Intraepithelial Neoplasia (CIN) exhibits certain morphologic features that can be identified during a visual inspection exam. Immature and dysphasic cervical squamous epithelium turns white after application of acetic acid during the exam. The whitening process occurs visually over several minutes and subjectively discriminates between dysphasic and normal tissue. Digital imaging technologies allow us to assist the physician analyzing the acetic acid induced lesions (acetowhite region) in a fully automatic way. This paper reports a study designed to measure multiple parameters of the acetowhitening process from two images captured with a digital colposcope. One image is captured before the acetic acid application, and the other is captured after the acetic acid application. The spatial change of the acetowhitening is extracted using color and texture information in the post acetic acid image; the temporal change is extracted from the intensity and color changes between the post acetic acid and pre acetic acid images with an automatic alignment. The imaging and data analysis system has been evaluated with a total of 99 human subjects and demonstrate its potential to screening underserved women where access to skilled colposcopists is limited.

  5. Crystal structure of a mixed solvated form of amoxapine acetate.

    PubMed

    Bhardwaj, Rajni M; Raval, Vishal; Oswald, Iain D H; Florence, Alastair J

    2015-02-01

    The mixed solvated salt 4-(2-chloro-dibenzo[b,f][1,4]oxazepin-11-yl)piperazin-1-ium acetate-acetic acid-cyclo-hexane (2/2/1), C17H17ClN3O(+)·C2H3O2 (-)·C2H4O2·0.5C6H12, crystallizes with one mol-ecule of protonated amoxapine (AXPN), an acetate anion and a mol-ecule of acetic acid together with half a mol-ecule of cyclo-hexane. In the centrosymmetric crystal, both enanti-omers of the protonated AXPN mol-ecule stack alternatively along [001]. Acetate anions connect the AXPN cations through N-H⋯O hydrogen bonding in the [010] direction, creating a sheet lying parallel to (100). The acetic acid mol-ecules are linked to the acetate anions via O-H⋯O hydrogen bonds within the sheets. Within the sheets there are also a number of C-H⋯O hydrogen bonds present. The cyclo-hexane solvent mol-ecules occupy the space between the sheets.

  6. Increased brain uptake and oxidation of acetate in heavy drinkers.

    PubMed

    Jiang, Lihong; Gulanski, Barbara Irene; De Feyter, Henk M; Weinzimer, Stuart A; Pittman, Brian; Guidone, Elizabeth; Koretski, Julia; Harman, Susan; Petrakis, Ismene L; Krystal, John H; Mason, Graeme F

    2013-04-01

    When a person consumes ethanol, the body quickly begins to convert it to acetic acid, which circulates in the blood and can serve as a source of energy for the brain and other organs. This study used 13C magnetic resonance spectroscopy to test whether chronic heavy drinking is associated with greater brain uptake and oxidation of acetic acid, providing a potential metabolic reward or adenosinergic effect as a consequence of drinking. Seven heavy drinkers, who regularly consumed at least 8 drinks per week and at least 4 drinks per day at least once per week, and 7 light drinkers, who consumed fewer than 2 drinks per week were recruited. The subjects were administered [2-13C]acetate for 2 hours and scanned throughout that time with magnetic resonance spectroscopy of the brain to observe natural 13C abundance of N-acetylaspartate (NAA) and the appearance of 13C-labeled glutamate, glutamine, and acetate. Heavy drinkers had approximately 2-fold more brain acetate relative to blood and twice as much labeled glutamate and glutamine. The results show that acetate transport and oxidation are faster in heavy drinkers compared with that in light drinkers. Our finding suggests that a new therapeutic approach to supply acetate during alcohol detoxification may be beneficial. PMID:23478412

  7. SAGA complex components and acetate repression in Aspergillus nidulans.

    PubMed

    Georgakopoulos, Paraskevi; Lockington, Robin A; Kelly, Joan M

    2012-11-01

    Alongside the well-established carbon catabolite repression by glucose and other sugars, acetate causes repression in Aspergillus nidulans. Mutations in creA, encoding the transcriptional repressor involved in glucose repression, also affect acetate repression, but mutations in creB or creC, encoding components of a deubiquitination system, do not. To understand the effects of acetate, we used a mutational screen that was similar to screens that uncovered mutations in creA, creB, and creC, except that glucose was replaced by acetate to identify mutations that were affected for repression by acetate but not by glucose. We uncovered mutations in acdX, homologous to the yeast SAGA component gene SPT8, which in growth tests showed derepression for acetate repression but not for glucose repression. We also made mutations in sptC, homologous to the yeast SAGA component gene SPT3, which showed a similar phenotype. We found that acetate repression is complex, and analysis of facA mutations (lacking acetyl CoA synthetase) indicates that acetate metabolism is required for repression of some systems (proline metabolism) but not for others (acetamide metabolism). Although plate tests indicated that acdX- and sptC-null mutations led to derepressed alcohol dehydrogenase activity, reverse-transcription quantitative real-time polymerase chain reaction showed no derepression of alcA or aldA but rather elevated induced levels. Our results indicate that acetate repression is due to repression via CreA together with metabolic changes rather than due to an independent regulatory control mechanism.

  8. Stable carbon isotope discrimination in rice field soil during acetate turnover by syntrophic acetate oxidation or acetoclastic methanogenesis

    NASA Astrophysics Data System (ADS)

    Conrad, Ralf; Klose, Melanie

    2011-03-01

    Rice fields are an important source for the greenhouse gas methane. In Italian rice field soil CH 4 is produced either by hydrogenotrophic and acetoclastic methanogenesis, or by hydrogenotrophic methanogenesis and syntrophic acetate oxidation when temperatures are below and above about 40-45 °C, respectively. In order to see whether these acetate consumption pathways differently discriminate the stable carbon isotopes of acetate, we measured the δ 13C of total acetate and acetate-methyl as well as the δ 13C of CO 2 and CH 4 in rice field soil that had been pre-incubated at 45 °C and then shifted to different temperatures between 25 and 50 °C. Acetate transiently accumulated to about 6 mM, which is about one-third of the amount of CH 4 produced, irrespective of the incubation temperature and the CH 4 production pathway involved. However, the patterns of δ 13C of the CH 4 and CO 2 produced were different at low (25, 30, 35 °C) versus high (40, 45, 50 °C) temperatures. These patterns were consistent with CH 4 being exclusively formed by hydrogenotrophic methanogenesis at high temperatures, and by a combination of acetoclastic and hydrogenotrophic methanogenesis at low temperatures. The patterns of δ 13C of total acetate and acetate-methyl were also different at high versus low temperatures, indicating the involvement of different pathways of production and consumption of acetate at the two temperature regimes. Isotope fractionation during consumption of the methyl group of acetate was more pronounced at low ( α = 1.010-1.025) than at high ( α = 1.0-1.01) temperatures indicating that acetoclastic methanogenesis exhibits a stronger isotope effect than syntrophic acetate oxidation. Small amounts of propionate also transiently accumulated and were analyzed for δ 13C. The δ 13C values slightly increased (by about 10‰) during production and consumption of propionate, but were not affected by incubation temperature. Collectively, our results showed distinct

  9. Viscosity of Mixtures of α-Tocopherol Acetate + Mesitylene

    NASA Astrophysics Data System (ADS)

    Szwajczaka, Elżbieta; Stagraczyński, Ryszard; Herba, Henryk; Świergielb, Jolanta; Jadżyn, Jan

    2009-08-01

    The paper presents results of the share viscosity measurements performed as a function of temperature and concentration for mixtures of α-tocopherol acetate (vitamine E acetate) and mesitylene, two liquids of essentially different viscosity (four order of magnitude difference at 280 K). The viscosity/ temperature dependence for pure α-tocopherol acetate as well as for the mixtures studied can be well described with the Vogel-Fulcher-Tammann equation. The viscosities of the mixtures exhibit a strong negative deviation from the rule of additive dependence on concentration and for increasing temperature the maximum value of the deviation shows an exponential decreasing.

  10. [Octreotide acetate for persistent cylothorax after descending aorta replacement].

    PubMed

    Naganuma, Hirokuni; Kawahito, Koji; Matsumura, Yoko; Nakamura, Ken; Haijima, Norimasa

    2010-12-01

    Cylothorax is one of a hazardous complication after thoracic aorta replacement. In this paper, we report effectiveness of octreotide acetate for postoperative persistent cylothorax. A 59-year-old female was referred to our hospital for chest pain. Previously she underwent arch reconstruction following aortic root replacement due to aortic dissection. Computed tomography (CT) revealed acute dissection on dissected descending aorta. Urgent descending aorta replacement was performed. After surgery, massive chylothoracic pleural fluid was drainaged. Although conventional medical treatment was not effective, drainage of chylothoracic pleural fluid significantly decreased after administration of octreotide acetate. Although mechanism has not been fully investigated, octreotide acetate was effective for persistent cylothorax after descending aorta replacement.

  11. Clostridiumm ljungdahlii, an anaerobic ethanol and acetate producing microorganism

    DOEpatents

    Gaddy, J.L.; Clausen, E.C.

    1992-12-22

    A newly discovered microorganism was isolated in a biologically pure culture and designated Clostridium ljungdahlii, having the identifying characteristics of ATCC No. 49587. Cultured in an aqueous nutrient medium under anaerobic conditions, this microorganism is capable of producing ethanol and acetate from CO and H[sub 2]O and/or CO[sub 2] and H[sub 2] in synthesis gas. Under optimal growth conditions, the microorganism produces acetate in preference to ethanol. Conversely, under non-growth conditions, ethanol production is favored over acetate. 3 figs.

  12. Clostridiumm ljungdahlii, an anaerobic ethanol and acetate producing microorganism

    DOEpatents

    Gaddy, James L.; Clausen, Edgar C.

    1992-01-01

    A newly discovered microorganism was isolated in a biologically pure culture and designated Clostridium ljungdahlii, having the identifying characteristics of ATCC No. 49587. Cultured in an aqueous nutrient medium under anaerobic conditions, this microorganism is capable of producing ethanol and acetate from CO and H.sub.2 O and/or CO.sub.2 and H.sub.2 in synthesis gas. Under optimal growth conditions, the microorganism produces acetate in preference to ethanol. Conversely, under non-growth conditions, ethanol production is favored over acetate.

  13. Leuprolide acetate suppresses pedophilic urges and arousability.

    PubMed

    Schober, Justine M; Kuhn, Phyllis J; Kovacs, Paul G; Earle, James H; Byrne, Peter M; Fries, Ruth A

    2005-12-01

    Cognitive-behavioral psychotherapy was compared with cognitive-behavioral psychotherapy augmented by leuprolide acetate (LA) for suppression of pedophilic behavior. Five male pedophiles (M age, 50 years; range, 36-58) were administered LA by Depo injection for 12 months, followed by saline placebo for 12 months. Testosterone levels, sexual interest preference by visual reaction time (Abel Assessment), penile tumescence (Monarch Penile Plethysmography, PPG), as well as strong sexual urges toward children and masturbatory frequency involving thoughts of children (polygraph), were measured every 3 months. On LA, testosterone decreased to castrate levels. Penile tumescence was significantly suppressed compared with baseline, but sufficient response remained to detect pedophilic interest. Pedophilic interest was also detected by visual reaction times. When asked about having pedophilic urges and masturbating to thoughts of children, all subjects self-reported a decrease. Polygraph responses indicated subjects were not deceptive. On placebo, testosterone and physiologic arousal eventually rose to baseline. As noted by polygraph, at baseline and on placebo, subjects were deceptive regarding increased pedophilic urges and masturbatory frequency. Interest preference, as measured by Abel Assessment and Monarch PPG, was generally unchanged throughout the study. Cognitive-behavioral psychotherapy augmented with LA significantly reduced pedophilic fantasies, urges, and masturbation; however, pedophilic interest did not change during 1 year of therapy. Deceptive responses by polygraph suggested that self-report was unreliable. Follow-up utilizing objective measures is essential for monitoring efficacy of treatment in pedophilia. Our study supports the premise that suppression of pedophilic behavior is possible. LA may augment cognitive-behavioral psychotherapy and help break the sequence leading to a re-offense.

  14. Comparison of growth, acetate production, and acetate inhibition of Escherichia coli strains in batch and fed-batch fermentations.

    PubMed Central

    Luli, G W; Strohl, W R

    1990-01-01

    The growth characteristics and acetate production of several Escherichia coli strains were compared by using shake flasks, batch fermentations, and glucose-feedback-controlled fed-batch fermentations to assess the potential of each strain to grow at high cell densities. Of the E. coli strains tested, including JM105, B, W3110, W3100, HB101, DH1, CSH50, MC1060, JRG1046, and JRG1061, strains JM105 and B were found to have the greatest relative biomass accumulation, strain MC1060 accumulated the highest concentrations of acetic acid, and strain B had the highest growth rates under the conditions tested. In glucose-feedback-controlled fed-batch fermentations, strains B and JM105 produced only 2 g of acetate.liter-1 while accumulating up to 30 g of biomass.liter-1. Under identical conditions, strains HB101 and MC1060 accumulated less than 10 g of biomass.liter-1 and strain MC1060 produced 8 g of acetate.liter-1. The addition of various concentrations of sodium acetate to the growth medium resulted in a logarithmic decrease, with respect to acetate concentration, in the growth rates of E. coli JM105, JM105(pOS4201), and JRG1061. These data indicated that the growth of the E. coli strains was likely to be inhibited by the acetate they produced when grown on media containing glucose. A model for the inhibition of growth of E. coli by acetate was derived from these experiments to explain the inhibition of acetate on E. coli strains at neutral pH. PMID:2187400

  15. Comparison of growth, acetate production, and acetate inhibition of Escherichia coli strains in batch and fed-batch fermentations.

    PubMed

    Luli, G W; Strohl, W R

    1990-04-01

    The growth characteristics and acetate production of several Escherichia coli strains were compared by using shake flasks, batch fermentations, and glucose-feedback-controlled fed-batch fermentations to assess the potential of each strain to grow at high cell densities. Of the E. coli strains tested, including JM105, B, W3110, W3100, HB101, DH1, CSH50, MC1060, JRG1046, and JRG1061, strains JM105 and B were found to have the greatest relative biomass accumulation, strain MC1060 accumulated the highest concentrations of acetic acid, and strain B had the highest growth rates under the conditions tested. In glucose-feedback-controlled fed-batch fermentations, strains B and JM105 produced only 2 g of acetate.liter-1 while accumulating up to 30 g of biomass.liter-1. Under identical conditions, strains HB101 and MC1060 accumulated less than 10 g of biomass.liter-1 and strain MC1060 produced 8 g of acetate.liter-1. The addition of various concentrations of sodium acetate to the growth medium resulted in a logarithmic decrease, with respect to acetate concentration, in the growth rates of E. coli JM105, JM105(pOS4201), and JRG1061. These data indicated that the growth of the E. coli strains was likely to be inhibited by the acetate they produced when grown on media containing glucose. A model for the inhibition of growth of E. coli by acetate was derived from these experiments to explain the inhibition of acetate on E. coli strains at neutral pH. PMID:2187400

  16. Inhibition of ice growth and recrystallization by zirconium acetate and zirconium acetate hydroxide.

    PubMed

    Mizrahy, Ortal; Bar-Dolev, Maya; Guy, Shlomit; Braslavsky, Ido

    2013-01-01

    The control over ice crystal growth, melting, and shaping is important in a variety of fields, including cell and food preservation and ice templating for the production of composite materials. Control over ice growth remains a challenge in industry, and the demand for new cryoprotectants is high. Naturally occurring cryoprotectants, such as antifreeze proteins (AFPs), present one solution for modulating ice crystal growth; however, the production of AFPs is expensive and inefficient. These obstacles can be overcome by identifying synthetic substitutes with similar AFP properties. Zirconium acetate (ZRA) was recently found to induce the formation of hexagonal cavities in materials prepared by ice templating. Here, we continue this line of study and examine the effects of ZRA and a related compound, zirconium acetate hydroxide (ZRAH), on ice growth, shaping, and recrystallization. We found that the growth rate of ice crystals was significantly reduced in the presence of ZRA and ZRAH, and that solutions containing these compounds display a small degree of thermal hysteresis, depending on the solution pH. The compounds were found to inhibit recrystallization in a manner similar to that observed in the presence of AFPs. The favorable properties of ZRA and ZRAH suggest tremendous potential utility in industrial applications.

  17. Cosolvent gel-like materials from partially hydrolyzed poly(vinyl acetate)s and borax.

    PubMed

    Angelova, Lora V; Terech, Pierre; Natali, Irene; Dei, Luigi; Carretti, Emiliano; Weiss, Richard G

    2011-09-20

    A gel-like, high-viscosity polymeric dispersion (HVPD) based on cross-linked borate, partially hydrolyzed poly(vinyl acetate) (xPVAc, where x is the percent hydrolysis) is described. Unlike hydro-HVPDs prepared from poly(vinyl alcohol) (PVA) and borate, the liquid portion of these materials can be composed of up to 75% of an organic cosolvent because of the influence of residual acetate groups on the polymer backbone. The effects of the degree of hydrolysis, molecular weight, polymer and cross-linker concentrations, and type and amount of organic cosolvent on the rheological and structural properties of the materials are investigated. The stability of the systems is explored through rheological and melting-range studies. (11)B NMR and small-angle neutron scattering (SANS) are used to probe the structure of the dispersions. The addition of an organic liquid to the xPVAc-borate HVPDs results in a drastic increase in the number of cross-linked borate species as well as the agglomeration of the polymer into bundles. These effects result in an increase in the relaxation time and thermal stability of the networks. The ability to make xPVAc-borate HVPDs with very large amounts of and rather different organic liquids, with very different rheological properties that can be controlled easily, opens new possibilities for applications of PVAc-based dispersions.

  18. Acetate-utilizing bacteria at an oxic-anoxic interface in the Baltic Sea.

    PubMed

    Berg, Carlo; Beckmann, Sabrina; Jost, Günter; Labrenz, Matthias; Jürgens, Klaus

    2013-08-01

    Pelagic redoxclines represent chemical gradients of elevated microbial activities. While chemolithoautotrophic microorganisms in these systems are well known as catalysts of major biogeochemical cycles, comparable knowledge on heterotrophic organisms is scarce. Thus, in this study, identity and biogeochemical involvement of active heterotrophs were investigated in stimulation experiments and activity measurements based on samples collected from pelagic redoxclines of the central Baltic Sea in 2005 and 2009. In the 2009 samples, (13)C-acetate 16S rRNA stable isotope probing (16S rRNA-SIP) identified gammaproteobacteria affiliated with Colwellia sp. and Neptunomonas sp. in addition to epsilonproteobacteria related to Arcobacter spp. as active heterotrophs at the oxic-anoxic interface layer. Incubations from sulfidic waters were dominated by two phylogenetic subgroups of Arcobacter. In the 2005 samples, organics, manganese(IV), and iron(III) were added to the sulfidic waters, followed by the determination of metal reduction and identification of the stimulated organisms. Here, the same Arcobacter and Colwellia subgroups were stimulated as in 2009, with Arcobacter predominating in samples, in which manganese(IV) reduction was highest. Our results offer new insights into the heterotrophic bacterial assemblage of Baltic Sea pelagic redoxclines and suggest Arcobacter spp. as a heterotroph with presumed relevance also for manganese cycling.

  19. Pseudomonas pyocyanin stimulates IL-8 expression through MAPK and NF-κB pathways in differentiated U937 cells

    PubMed Central

    2014-01-01

    Background Pyocyanin (PCN), an extracellular product of Pseudomonas aeruginosa and a blue redox active secondary metabolite, plays an important role in invasive pulmonary infection. However, the detailed inflammatory response triggered by PCN infection in inflammatory cells (particularly macrophages), if present, remains to be clarified. To investigate the effects of PCN on macrophages, the ability of PCN to induce inflammation reaction and the signaling pathway for IL-8 release in PCN-induced differentiated U937 cells were examined. Results It was found that PCN increased IL-8 release and mRNA expression in Phorbol 12-myristate 13-acetate (PMA) differentiated U937 cells in both a concentration- and time-dependent manner by reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). P38 and ERK MAPKs were activated after 10 min of induction with PCN and their levels returned to baselines after 30 min by Western blotting. It was also found that within 10 min of PCN incubation, the level of p-I-κBα in the cytosol was increased, which returned to baseline level after 60 min. Meanwhile, the level of p-p65 was increased in the nuclear extract and cytosol, and maintained high in total cell lysates. The results were further confirmed by the observation that p38, ERK1/2 and NF-κB inhibitors inhibited PCN-induced NF-κB activation and attenuated PCN-induced IL-8 expression in U937 cells as a function of their concentrations. Moreover, it was shown that PCN induced oxidative stress in U937 cells and N-acetyl cysteine, an antioxidant, was able to inhibit PCN-induced IL-8 protein expression. Conclusions It is concluded that PCN induces IL-8 secretion and mRNA expression in PMA-differentiated U937 cells in a concentration- and time- dependent manner. Furthermore, p38 and ERK MAPKs and NF-κΒ signaling pathways may be involved in the expression of IL-8 in PCN-incubated PMA-differentiated U937 cells. PMID:24499192

  20. 21 CFR 522.2478 - Trenbolone acetate and estradiol benzoate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ....240 and 556.739 of this chapter. (d) Conditions of use—(1) Steers fed in confinement for slaughter. (i...) Heifers fed in confinement for slaughter—(i) Amount. 200 mg trenbolone acetate and 28 mg...

  1. Extruding foams from corn starch acetate and native corn starch.

    PubMed

    Guan, Junjie; Hanna, Milford A

    2004-01-01

    Because of the hydrophilic characteristics of native starch foams and the cost of modifying starch, the uses of starch and modified starch foams are hindered. To decrease hydrophilicity and cost of starch foams, native corn starch was blended with starch acetate and extruded. A twin-screw mixing extruder was used to produce the foams. Native starch content, screw speed, and barrel temperature had significant effects on molecular degradation of starches during extrusion. The melting temperature of extruded starch acetate/native starch foam was higher (216 degrees C) than that for starch acetate (193.4 degrees C). Strong peaks in the X-ray diffractograms of extruded starch acetate/native starch foam suggested new crystalline regions were formed. Optimum conditions for high radial expansion ratio, high compressibility, low specific mechanical energy requirement, and low water absorption index were 46.0% native starch content, 163 rpm screw speed, and 148 degrees C barrel temperature.

  2. Ice-melting characteristics of calcium magnesium acetate

    NASA Astrophysics Data System (ADS)

    Schenk, R. U.

    1986-01-01

    The objectives of the study are to determine the pertinent properties of Calcium/Magnesium Acetate and to determine the pH and ratio of calcium to magnesium that provide optimum road deicing characteristics.

  3. Fragrance material review on p-isopropylbenzyl acetate.

    PubMed

    McGinty, D; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of p-isopropylbenzyl acetate when used as a fragrance ingredient is presented. p-Isopropylbenzyl acetate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1 to 4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for p-isopropylbenzyl acetate were evaluated, then summarized, and includes: physical properties, acute toxicity, skin irritation, and skin sensitization data. A safety assessment of the entire AAASAE will be published simultaneously with this document. Please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all AAASAE in fragrances.

  4. Fragrance material review on 2-hydroxy-2-phenylethyl acetate.

    PubMed

    McGinty, D; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of 2-hydroxy-2-phenylethyl acetate when used as a fragrance ingredient is presented. 2-Hydroxy-2-phenylethyl acetate is a member of the fragrance structural group aryl alkyl alcohol simple acid esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1-4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for 2-hydroxy-2-phenylethyl acetate was evaluated then summarized and includes physical properties data. A safety assessment of the entire AAASAE will be published simultaneously with this document. Please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all AAASAE in fragrances.

  5. Fragrance material review on ethyl phenyl carbinyl acetate.

    PubMed

    McGinty, D; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of ethyl phenyl carbinyl acetate when used as a fragrance ingredient is presented. Ethyl phenyl carbinyl acetate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1-4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for ethyl phenyl carbinyl acetate were evaluated, then summarized, and includes: physical properties; acute toxicity; skin irritation; and skin sensitization data. A safety assessment of the entire AAASAE will be published simultaneously with this document; please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all AAASAE in fragrances.

  6. Fragrance material review on 2-(p-tolyloxy)ethyl acetate.

    PubMed

    McGinty, D; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of 2-(p-tolyloxy)ethyl acetate when used as a fragrance ingredient is presented. 2-(p-tolyloxy)ethyl acetate is a member of the fragrance structural group aryl alkyl alcohol simple acid esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1-4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for 2-(p-tolyloxy)ethyl acetate were evaluated, then summarized, and includes physical properties data. A safety assessment of the entire AAASAE will be published simultaneously with this document. Please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all AAASAE in fragrances.

  7. Biosynthesis of the halogenated auxin, 4-chloroindole-3-acetic acid.

    PubMed

    Tivendale, Nathan D; Davidson, Sandra E; Davies, Noel W; Smith, Jason A; Dalmais, Marion; Bendahmane, Abdelhafid I; Quittenden, Laura J; Sutton, Lily; Bala, Raj K; Le Signor, Christine; Thompson, Richard; Horne, James; Reid, James B; Ross, John J

    2012-07-01

    Seeds of several agriculturally important legumes are rich sources of the only halogenated plant hormone, 4-chloroindole-3-acetic acid. However, the biosynthesis of this auxin is poorly understood. Here, we show that in pea (Pisum sativum) seeds, 4-chloroindole-3-acetic acid is synthesized via the novel intermediate 4-chloroindole-3-pyruvic acid, which is produced from 4-chlorotryptophan by two aminotransferases, TRYPTOPHAN AMINOTRANSFERASE RELATED1 and TRYPTOPHAN AMINOTRANSFERASE RELATED2. We characterize a tar2 mutant, obtained by Targeting Induced Local Lesions in Genomes, the seeds of which contain dramatically reduced 4-chloroindole-3-acetic acid levels as they mature. We also show that the widespread auxin, indole-3-acetic acid, is synthesized by a parallel pathway in pea. PMID:22573801

  8. Acetate utilization and macromolecular synthesis during sporulation of yeast.

    PubMed

    Esposito, M S; Esposito, R E; Arnaud, M; Halvorson, H O

    1969-10-01

    Acetate utilization and macromolecule synthesis during sporulation (meiosis) of Saccharomyces cerevisiae were studied. When diploid cells are transferred from glucose nutrient medium to acetate sporulation medium at early stationary phase, respiration of the exogenously supplied acetate proceeds without any apparent lag. At the completion of ascospore development, 62% of the acetate carbon consumed has been respired, 22% remains in the soluble pool, and 16% is incorporated into lipids, protein, nucleic acids, and other cell components. Measurements of the rate of protein synthesis during sporulation reveal two periods of maximal synthetic activity: an early phase coincidental with increases in deoxyribonucleic acid, ribonucleic acid, and protein cellular content and a later phase during ascospore formation. Experiments in which protein synthesis was inhibited at intervals during sporulation indicate that protein synthesis is required both for the initiation and completion of ascus development.

  9. Fragrance material review on 2-(p-tolyloxy)ethyl acetate.

    PubMed

    McGinty, D; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of 2-(p-tolyloxy)ethyl acetate when used as a fragrance ingredient is presented. 2-(p-tolyloxy)ethyl acetate is a member of the fragrance structural group aryl alkyl alcohol simple acid esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1-4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for 2-(p-tolyloxy)ethyl acetate were evaluated, then summarized, and includes physical properties data. A safety assessment of the entire AAASAE will be published simultaneously with this document. Please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all AAASAE in fragrances. PMID:22414652

  10. Acetoxychavicol Acetate, an Antifungal Component of Alpinia galanga1.

    PubMed

    Janssen, A M; Scheffer, J J

    1985-12-01

    The essential oils from fresh and dried rhizomes of ALPINIA GALANGA showed an antimicrobial activity against gram-positive bacteria, a yeast and some dermatophytes, using the agar overlay technique. The main components of the oils were also tested and terpinen-4-ol was found most active. An N-pentane/diethyl ether extract of dried rhizomes was active against TRICHOPHYTON MENTAGROPHYTES. 1'-Acetoxychavicol acetate, 1'-acetoxyeugenol acetate and 1'-hydroxychavicol acetate identified by MS and NMR were found in the antifungally active fractions obtained by LSC. Acetoxychavicol acetate was active against the seven fungi tested and its MIC value for dermatophytes ranged from 50 to 250 microg/ml. Dried sliced rhizomes contained 1.5% of this compound. The compound was not found in rhizomes of ALPINIA OFFICINARUM, ZINGIBER OFFICINALE and KAEMPFERIA GALANGA.

  11. Human macrophage differentiation involves an interaction between integrins and fibronectin

    SciTech Connect

    Laouar, A.; Chubb, C.B.H.; Collart, F.; Huberman, E.

    1997-03-14

    The authors have examined the role of integrins and extracellular matrix (ECM) proteins in macrophage differentiation of (1) human HL-60 myeloid leukemia cells induced by phorbol 12-myristate 13-acetate (PMA) and (2) human peripheral blood monocytes induced by either PMA or macrophage-colony stimulating factor (M-CSF). Increased {beta}{sub 1} integrin and fibronectin (FN) gene expression was observed in PMA-treated HL-60 cells and PMA- or M-CSF-treated monocytes, even at a time preceding the manifestation of macrophage markers. Treated HL-60 cells and monocytes also released and deposited FN on the culture dishes. An HL-60 cell variant, HL-525, which is deficient in protein kinase C {beta} (PKC{beta}) and resistant to PMA-induced differentiation, failed to express FN after PMA treatment. Restoration of PKC{beta} resulted in PMA-induced FN gene expression and macrophage differentiation. The macrophage phenotype induced in HL-60 cells or monocytes was attenuated by anti-{beta}{sub 1} integrin or anti-FN MAbs. The authors suggest that macrophage differentiation involves activation of PKC and expression of specific integrins and ECM proteins. The stimulated cells, through their integrins, attach and spread on these substrates by binding to the deposited ECM proteins. This attachment and spreading in turn, through integrin signaling, leads to the macrophage phenotype.

  12. Vagus Nerve Stimulation

    PubMed Central

    Howland, Robert H.

    2014-01-01

    The vagus nerve is a major component of the autonomic nervous system, has an important role in the regulation of metabolic homeostasis, and plays a key role in the neuroendocrine-immune axis to maintain homeostasis through its afferent and efferent pathways. Vagus nerve stimulation (VNS) refers to any technique that stimulates the vagus nerve, including manual or electrical stimulation. Left cervical VNS is an approved therapy for refractory epilepsy and for treatment resistant depression. Right cervical VNS is effective for treating heart failure in preclinical studies and a phase II clinical trial. The effectiveness of various forms of non-invasive transcutaneous VNS for epilepsy, depression, primary headaches, and other conditions has not been investigated beyond small pilot studies. The relationship between depression, inflammation, metabolic syndrome, and heart disease might be mediated by the vagus nerve. VNS deserves further study for its potentially favorable effects on cardiovascular, cerebrovascular, metabolic, and other physiological biomarkers associated with depression morbidity and mortality. PMID:24834378

  13. Microorganisms having enhanced resistance to acetate and methods of use

    SciTech Connect

    Brown, Steven D; Yang, Shihui

    2014-10-21

    The present invention provides isolated or genetically modified strains of microorganisms that display enhanced resistance to acetate as a result of increased expression of a sodium proton antiporter. The present invention also provides methods for producing such microbial strains, as well as related promoter sequences and expression vectors. Further, the present invention provides methods of producing alcohol from biomass materials by using microorganisms with enhanced resistance to acetate.

  14. Water dispersible microbicidal cellulose acetate phthalate film

    PubMed Central

    Neurath, A Robert; Strick, Nathan; Li, Yun-Yao

    2003-01-01

    Background Cellulose acetate phthalate (CAP) has been used for several decades in the pharmaceutical industry for enteric film coating of oral tablets and capsules. Micronized CAP, available commercially as "Aquateric" and containing additional ingredients required for micronization, used for tablet coating from water dispersions, was shown to adsorb and inactivate the human immunodeficiency virus (HIV-1), herpesviruses (HSV) and other sexually transmitted disease (STD) pathogens. Earlier studies indicate that a gel formulation of micronized CAP has a potential as a topical microbicide for prevention of STDs including the acquired immunodeficiency syndrome (AIDS). The objective of endeavors described here was to develop a water dispersible CAP film amenable to inexpensive industrial mass production. Methods CAP and hydroxypropyl cellulose (HPC) were dissolved in different organic solvent mixtures, poured into dishes, and the solvents evaporated. Graded quantities of a resulting selected film were mixed for 5 min at 37°C with HIV-1, HSV and other STD pathogens, respectively. Residual infectivity of the treated viruses and bacteria was determined. Results The prerequisites for producing CAP films which are soft, flexible and dispersible in water, resulting in smooth gels, are combining CAP with HPC (other cellulose derivatives are unsuitable), and casting from organic solvent mixtures containing ≈50 to ≈65% ethanol (EtOH). The films are ≈100 µ thick and have a textured surface with alternating protrusions and depressions revealed by scanning electron microscopy. The films, before complete conversion into a gel, rapidly inactivated HIV-1 and HSV and reduced the infectivity of non-viral STD pathogens >1,000-fold. Conclusions Soft pliable CAP-HPC composite films can be generated by casting from organic solvent mixtures containing EtOH. The films rapidly reduce the infectivity of several STD pathogens, including HIV-1. They are converted into gels and thus do not

  15. New York Canyon Stimulation

    SciTech Connect

    Raemy, Bernard

    2012-06-21

    The New York Canyon Stimulation Project was to demonstrate the commercial application of Enhanced Geothermal System techniques in Buena Vista Valley area of Pershing County, Nevada. From October 2009 to early 2012, TGP Development Company aggressively implemented Phase I of Pre-Stimulation and Site/Wellbore readiness. This included: geological studies; water studies and analyses and procurement of initial permits for drilling. Oversubscription of water rights and lack of water needed for implementation of EGS were identified and remained primary obstacles. Despite extended efforts to find alternative solutions, the water supply circumstances could not be overcome and led TGP to determine a "No Go" decision and initiate project termination in April 2012.

  16. Muscle Stimulation Technology

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Under a Goddard Space Flight Center contract, Electrologic of America was able to refine the process of densely packing circuitry on personal computer boards, providing significant contributions to the closed-loop systems for the Remote Manipulator System Simulator. The microcircuitry work was then applied to the StimMaster FES Ergometer, an exercise device used to stimulate muscles suffering from paralysis. The electrical stimulation equipment was developed exclusively for V-Care Health Systems, Inc. Product still commercially available as of March 2002.

  17. Genetic organization of Acetobacter for acetic acid fermentation.

    PubMed

    Beppu, T

    Plasmid vectors for the acetic acid-producing strains of Acetobacter and Gluconobacter were constructed from their cryptic plasmids and the efficient transformation conditions were established. The systems allowed to reveal the genetic background of the strains used in the acetic acid fermentation. Genes encoding indispensable components in the acetic acid fermentation, such as alcohol dehydrogenase, aldehyde dehydrogenase and terminal oxidase, were cloned and characterized. Spontaneous mutations at high frequencies in the acetic acid bacteria to cause the deficiency in ethanol oxidation were analyzed. A new insertion sequence element, IS1380, was identified as a major factor of the genetic instability, which causes insertional inactivation of the gene encoding cytochrome c, an essential component of the functional alcohol dehydrogenase complex. Several genes including the citrate synthase gene of A. aceti were identified to confer acetic acid resistance, and the histidinolphosphate aminotransferase gene was cloned as a multicopy suppressor of an ethanol sensitive mutant. Improvement of the acetic acid productivity of an A. aceti strain was achieved through amplification of the aldehyde dehydrogenase gene with a multicopy vector. In addition, spheroplast fusion of the Acetobacter strains was developed and applied to improve their properties.

  18. Genetic dissection of acetic acid tolerance in Saccharomyces cerevisiae.

    PubMed

    Geng, Peng; Xiao, Yin; Hu, Yun; Sun, Haiye; Xue, Wei; Zhang, Liang; Shi, Gui-Yang

    2016-09-01

    Dissection of the hereditary architecture underlying Saccharomyces cerevisiae tolerance to acetic acid is essential for ethanol fermentation. In this work, a genomics approach was used to dissect hereditary variations in acetic acid tolerance between two phenotypically different strains. A total of 160 segregants derived from these two strains were obtained. Phenotypic analysis indicated that the acetic acid tolerance displayed a normal distribution in these segregants, and suggested that the acetic acid tolerant traits were controlled by multiple quantitative trait loci (QTLs). Thus, 220 SSR markers covering the whole genome were used to detect QTLs of acetic acid tolerant traits. As a result, three QTLs were located on chromosomes 9, 12, and 16, respectively, which explained 38.8-65.9 % of the range of phenotypic variation. Furthermore, twelve genes of the candidates fell into the three QTL regions by integrating the QTL analysis with candidates of acetic acid tolerant genes. These results provided a novel avenue to obtain more robust strains. PMID:27430512

  19. Hormetic effect of ionic liquid 1-ethyl-3-methylimidazolium acetate on bacteria.

    PubMed

    Nancharaiah, Y V; Francis, A J

    2015-06-01

    The biological effect of ionic liquids (ILs) is one of the highly debated topics as they are being contemplated for various industrial applications. 1-ethyl-3-methylimidazolium acetate ([EMIM][Ac]) showed remarkable hormesis on anaerobic Clostridium sp. and aerobic Pseudomonas putida. Bacterial growth was stimulated at up to 2.5 g L(-1) and inhibited at >2.5 g L(-1) of [EMIM][Ac]. The growth of Clostridium sp. and P. putida were higher by 0.4 and 4-fold respectively, in the presence of 0.5 g L(-1) [EMIM][Ac]. Assessment of the effect of [EMIM][Ac] under different growth conditions showed that the hormesis of [EMIM][Ac] was mediated via regulation of medium pH. Hormetic effect of [EMIM][Ac] was evident only in medium with poor buffering capacity and in the presence of a fermentable substrate as the carbon source. The hormetic effect of [EMIM][Ac] on bacterial growth is most likely associated with the buffering capacity of acetate anion. These observations have implications in ILs toxicity studies and ecological risk assessment. PMID:25703901

  20. Acetate-free blood purification can impact improved nutritional status in hemodialysis patients.

    PubMed

    Matsuyama, Kazuhiro; Tomo, Tadashi; Kadota, Jun-ichi

    2011-06-01

    Effects of online hemodiafiltration (HDF) using acetate-free bicarbonate dialysis (AFD) fluid on microinflammation, resulting in improved nutritional status in hemodialysis patients, were examined and compared with conventional acetate-containing bicarbonate dialysis (ACD) fluid. A total of 24 hemodialysis patients were registered for a cross-over design study for a 6-month period. These patients were subjected to ACD for the first 3 months followed by AFD fluid for the latter 3 months. Blood variables of C-reactive protein (CRP), interleukin-6 (IL-6), leptin, neuropeptide Y (NPY), protein catabolic rate (PCR) and %creatinine (Cr) index were determined after the first and last 3-month period. The filters and the conditions of HDF and drug regimens including erythropoiesis-stimulating agents were unchanged throughout the cross-over study. Predialysis blood pH and bicarbonate were significantly higher in the AFD phase than in the ACD phase. Blood CRP and IL-6 levels were significantly decreased in the AFD group compared to the ACD group. Concerning nutritional evaluation, leptin and NPY were significantly lower and higher, respectively, in the AFD phase than in the ACD phase. PCR tended to be higher in the AFD phase than in the ACD phase. A significantly higher %Cr index level was observed in the AFD phase than in the ACD phase. These results suggest that online HDF using AFD fluid contributes to alleviating bioincompatible events associated with microinflammation, leading to improvement in the nutritional status in hemodialysis patients.

  1. Hormetic effect of ionic liquid 1-ethyl-3-methylimidazolium acetate on bacteria

    SciTech Connect

    Nancharaiah, Y. V.; Francis, A. J.

    2015-02-19

    The biological effect of ionic liquids (ILs) is one of the highly debated topics as they are being contemplated for various industrial applications. 1-ethyl-2-methylimidazolium acetate ([EMIM][Ac]) showed remarkable hormesis on anaerobic Clostridium sp. and aerobic Psueudomonas putida. Bacterial growth was stimulated at up to 2.5 g L-1 and inhibited at > 2.5 g L-1 of ([EMIM][Ac]). The growth of Clostridium sp. and P. putida were higher by 0.4 and 4-fold respectively, in the presense of 0.5 g L-1 of ([EMIM][Ac]). Assessment of the effect of [EMIM][Ac] under different growth conditions showed that the hormesis of [EMIM][Ac] was mediated via regulation of medium pH. Hormetic effect of [EMIM][Ac] was evident only in medium with poor buffering capacity and in the presence of a fermentable substrate as the carbon source. The hormetic effect of [EMIM][Ac] on bacterial growth is most likely associated with the buffering capacity of acetate anion. These observations have implications in ILs toxicity studies and ecological risk assessment.

  2. Hormetic effect of ionic liquid 1-ethyl-3-methylimidazolium acetate on bacteria

    DOE PAGES

    Nancharaiah, Y. V.; Francis, A. J.

    2015-02-19

    The biological effect of ionic liquids (ILs) is one of the highly debated topics as they are being contemplated for various industrial applications. 1-ethyl-2-methylimidazolium acetate ([EMIM][Ac]) showed remarkable hormesis on anaerobic Clostridium sp. and aerobic Psueudomonas putida. Bacterial growth was stimulated at up to 2.5 g L-1 and inhibited at > 2.5 g L-1 of ([EMIM][Ac]). The growth of Clostridium sp. and P. putida were higher by 0.4 and 4-fold respectively, in the presense of 0.5 g L-1 of ([EMIM][Ac]). Assessment of the effect of [EMIM][Ac] under different growth conditions showed that the hormesis of [EMIM][Ac] was mediated via regulationmore » of medium pH. Hormetic effect of [EMIM][Ac] was evident only in medium with poor buffering capacity and in the presence of a fermentable substrate as the carbon source. The hormetic effect of [EMIM][Ac] on bacterial growth is most likely associated with the buffering capacity of acetate anion. These observations have implications in ILs toxicity studies and ecological risk assessment.« less

  3. Lead acetate induced cytotoxicity in male germinal cells of Swiss mice.

    PubMed

    Acharya, U R; Acharya, S; Mishra, M

    2003-07-01

    Single intraperitoneal injection of lead acetate (200 mg/kg b.w) to Swiss mice stimulated testicular weight loss with a constant increase in the incidence of abnormal sperm population and decrease in the total sperm count. Testicular ascorbic acid also declined significantly during the post-treatment phase with significant rise in Lipid Peroxidation Potential (LPP) of the tissue. Elevated LPP is indicative of oxidative stress in treated mice testes. The possible role of lead-induced oxidative stress in culminating increased sperm abnormality and decreased sperm count have been discussed. Further, possible antioxidative role of testicular ascorbic acid in minimizing oxidative stress in lead-treated mice has been demonstrated. PMID:12916762

  4. [Programmed stimulation for in vitro fertilization].

    PubMed

    Imthurn, B; Macas, E; Hotz, E; Keller, P J

    1992-01-01

    A programmed stimulation protocol for in vitro fertilisation was evaluated in order to perform oocytes aspiration from Tuesday to Friday only. For this purpose, norethisterone acetate (Primolut-Nor) was given in a daily dose of 10 mg for 10-25 days, starting on the 2nd day of the preceding cycle and ending on a Monday. The stimulation was started on the following Friday by administering daily 0.1 mg D-Trp-6-LHRH s. c. (Decapeptyl). In group A (preliminary study) the treatment with HMG 150 IU/d (Pergonal) was initiated two days later. In group B the treatment with HMG was individualised with respect to the initial dose and the starting point. 10 ultrasonographic, needle-guided, transvaginal aspirations were performed from January to March 1990 in Group A, 29 aspirations from April to December 1990 in Group B. Indication for IVF in all patients was tubal infertility. All aspirations were possible from Tuesday to Friday. In Group A 5 of 15 cycles (33%) had to be cancelled. A total of 53 oocytes (5.3 +/- 2.3 per aspiration) were retrieved. Cleavage per oocyte took place in 62%. There was no pregnancy. In Group B, the cancellation rate could be reduced to 3% (1/30 cycles; p less than 0.025). 227 oocytes were recovered (7.8 +/- 3.1 per aspiration; p less than 0.05) and there was a higher cleavage rate (74%, n.s.). The clinical pregnancy rate (with allowance for progressive introduction of freezing) increased to 30% per stimulation cycle (9/30, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

  5. Recycling of carbon dioxide and acetate as lactic acid by the hydrogen-producing bacterium Thermotoga neapolitana.

    PubMed

    d'Ippolito, Giuliana; Dipasquale, Laura; Fontana, Angelo

    2014-09-01

    The heterotrophic bacterium Thermotoga neapolitana produces hydrogen by fermentation of sugars. Under capnophilic (carbon dioxide requiring) conditions, the process is preferentially associated with the production of lactic acid, which, as shown herein, is synthesized by reductive carboxylation of acetyl coenzyme A. The enzymatic coupling is dependent on the carbon dioxide stimulated activity of heterotetrameric pyruvate:ferredoxin oxidoreductase. Under the same culture conditions, T. neapolitana also operates the unfavorable synthesis of lactic acid from an exogenous acetate supply. This process, which requires carbon dioxide (or carbonate) and an unknown electron donor, allows for the conversion of carbon dioxide into added-value chemicals without biomass deconstruction.

  6. Identification of acetate- or methanol-assimilating bacteria under nitrate-reducing conditions by stable-isotope probing.

    PubMed

    Osaka, Toshifumi; Yoshie, Sachiko; Tsuneda, Satoshi; Hirata, Akira; Iwami, Norio; Inamori, Yuhei

    2006-08-01

    Stable-isotope probing (SIP) was used to identify acetate- or methanol-assimilating bacteria under nitrate-reducing conditions in activated sludge. A sludge sample obtained from wastewater treatment systems was incubated in a denitrifying batch reactor fed with synthetic wastewater containing [(13)C]acetate or [(13)C]methanol as the main carbon source and nitrate as the electron acceptor. We analyzed how growth of bacterial populations was stimulated by acetate or methanol as the external carbon source in nitrogen-removal systems. Most of the acetate- or methanol-assimilating bacteria identified by SIP have been known as denitrifiers in wastewater treatment systems. When acetate was used as the carbon source, 16S rRNA gene sequences retrieved from (13)C-labeled DNA were closely related to the 16S rRNA genes of Comamonadaceae (e.g., Comamonas and Acidovorax) and Rhodocyclaceae (e.g., Thauera and Dechloromonas) of the Betaproteobacteria, and Rhodobacteraceae (e.g., Paracoccus and Rhodobacter) of the Alphaproteobacteria. When methanol was used as the carbon source, 16S rRNA gene sequences retrieved from (13)C-DNA were affiliated with Methylophilaceae (e.g., Methylophilus, Methylobacillus, and Aminomonas) and Hyphomicrobiaceae. Rarefaction curves for clones retrieved from (13)C-DNA showed that the diversity levels for methanol-assimilating bacteria were considerably lower than those for acetate-assimilating bacteria. Furthermore, we characterized nitrite reductase genes (nirS and nirK) as functional marker genes for denitrifier communities in acetate- or methanol-assimilating populations and detected the nirS or nirK sequence related to that of some known pure cultures, such as Alcaligenes, Hyphomicrobium, and Thauera. However, most of the nirS or nirK sequences retrieved from (13)C-DNA were clustered in some unidentified groups. On the basis of 16S rRNA gene clone libraries retrieved from (13)C-DNA, these unidentified nir sequences might be identified by examining the

  7. Testosterone suppression of CRH-stimulated cortisol in men.

    PubMed

    Rubinow, David R; Roca, Catherine A; Schmidt, Peter J; Danaceau, Merry A; Putnam, Karen; Cizza, Giovanni; Chrousos, George; Nieman, Lynnette

    2005-10-01

    Despite observations of age-dependent sexual dimorphisms in hypothalamic-pituitary-adrenal (HPA) axis activity, the role of androgens in the regulation of HPA axis activity in men has not been examined. We assessed this role by performing CRH stimulation tests in 10 men (ages 18-45 years) during gonadal suppression with leuprolide acetate and during testosterone addition to leuprolide. CRH-stimulated cortisol levels as well as peak cortisol and greatest cortisol excursion were significantly lower (p<0.05, 0.005, and 0.01, respectively) during testosterone replacement compared with the induced hypogonadal condition (leuprolide plus placebo); cortisol area under the curve was lower at a trend level (p<0.1). Paradoxically, CRH-stimulated corticotropin (ACTH) was increased significantly during testosterone replacement (p<0.05). The cortisol : ACTH ratio, a measure of adrenal sensitivity, was lower during testosterone replacement (p<0.1). A mixed effects regression model showed that testosterone but not estradiol or CBG significantly contributed to the variance of cortisol. These data demonstrate that testosterone regulates CRH-stimulated HPA axis activity in men, with the divergent effects on ACTH and cortisol suggesting a peripheral (adrenal) locus for the suppressive effects on cortisol. Our results further demonstrate that the enhanced stimulated HPA axis activity previously described in young men compared with young women cannot be ascribed to an activational upregulation of the axis by testosterone.

  8. Tetrazole acetic acid: tautomers, conformers, and isomerization.

    PubMed

    Araujo-Andrade, C; Reva, I; Fausto, R

    2014-02-14

    Monomers of (tetrazol-5-yl)-acetic acid (TAA) were obtained by sublimation of the crystalline compound and the resulting vapors were isolated in cryogenic nitrogen matrices at 13 K. The conformational and tautomeric composition of TAA in the matrix was characterized by infrared spectroscopy and vibrational calculations carried out at the B3LYP/6-311++G(d,p) level. TAA may adopt two tautomeric modifications, 1H- and 2H-, depending on the position of the annular hydrogen atom. Two-dimensional potential energy surfaces (PESs) of TAA were theoretically calculated at the MP2/6-311++G(d,p) level, for each tautomer. Four and six symmetry-unique minima were located on these PESs, for 1H- and 2H-TAA, respectively. The energetics of the detected minima was subsequently refined by calculations at the QCISD level. Two 1H- and three 2H-conformers fall within the 0-8 kJ mol(-1) energy range and should be appreciably populated at the sublimation temperature (∼330 K). Observation of only one conformer for each tautomer (1ccc and 2pcc) is explained in terms of calculated barriers to conformational rearrangements. All conformers with the cis O=COH moiety are separated by low barriers (less than 10 kJ mol(-1)) and collapse to the most stable 1ccc (1H-) and 2pcc (2H-) forms during deposition of the matrix. On the trans O=COH surfaces, the relative energies are very high (between 12 and 27 kJ mol(-1)). The trans forms are not thermally populated at the sublimation conditions and were not detected in matrices. One high-energy form in each tautomer, 1cct (1H-) and 2pct (2H-), was found to differ from the most stable form only by rotation of the OH group and separated from other forms by high barriers. This opened a perspective for their stabilization in a matrix. 1cct and 2pct were generated in the matrices selectively by means of narrow-band near-infrared (NIR) irradiations of the samples at 6920 and 6937 cm(-1), where the first OH stretching overtone vibrations of 1ccc and 2pcc occur

  9. Tetrazole acetic acid: Tautomers, conformers, and isomerization

    SciTech Connect

    Araujo-Andrade, C.; Reva, I. Fausto, R.

    2014-02-14

    Monomers of (tetrazol-5-yl)-acetic acid (TAA) were obtained by sublimation of the crystalline compound and the resulting vapors were isolated in cryogenic nitrogen matrices at 13 K. The conformational and tautomeric composition of TAA in the matrix was characterized by infrared spectroscopy and vibrational calculations carried out at the B3LYP/6-311++G(d,p) level. TAA may adopt two tautomeric modifications, 1H- and 2H-, depending on the position of the annular hydrogen atom. Two-dimensional potential energy surfaces (PESs) of TAA were theoretically calculated at the MP2/6-311++G(d,p) level, for each tautomer. Four and six symmetry-unique minima were located on these PESs, for 1H- and 2H-TAA, respectively. The energetics of the detected minima was subsequently refined by calculations at the QCISD level. Two 1H- and three 2H-conformers fall within the 0–8 kJ mol{sup −1} energy range and should be appreciably populated at the sublimation temperature (∼330 K). Observation of only one conformer for each tautomer (1ccc and 2pcc) is explained in terms of calculated barriers to conformational rearrangements. All conformers with the cis O=COH moiety are separated by low barriers (less than 10 kJ mol{sup −1}) and collapse to the most stable 1ccc (1H-) and 2pcc (2H-) forms during deposition of the matrix. On the trans O=COH surfaces, the relative energies are very high (between 12 and 27 kJ mol{sup −1}). The trans forms are not thermally populated at the sublimation conditions and were not detected in matrices. One high-energy form in each tautomer, 1cct (1H-) and 2pct (2H-), was found to differ from the most stable form only by rotation of the OH group and separated from other forms by high barriers. This opened a perspective for their stabilization in a matrix. 1cct and 2pct were generated in the matrices selectively by means of narrow-band near-infrared (NIR) irradiations of the samples at 6920 and 6937 cm{sup −1}, where the first OH stretching overtone

  10. What does galvanic vestibular stimulation stimulate?

    PubMed

    Wardman, Daniel L; Fitzpatrick, Richard C

    2002-01-01

    The technique of galvanic vestibular stimulation (GVS) has been used for a long time. The stimulus produces stereotyped automatic postural and ocular responses. The mechanisms underlying these responses are not understood although they are commonly attributed to altered otolith output. Based on animal studies, it seems reasonable to assume that vestibular afferents from the otoliths and semicircular canals are affected similarly by GVS. With this assumption, and anatomical knowledge of the vestibular apparatus, a model is developed to describe the expected responses of vestibular afferents to percutaneous GVS and the physiological implications of this altered sensory signal. Bilateral bipolar GVS, the most commonly used technique, should produce a canal signal consistent with a strong ear-down roll towards the cathodal side, a smaller nose-to-cathode yaw, but no pitch signal. Bilateral bipolar GVS should also produce an otolith signal consistent with tilt towards the cathodal side or a translational acceleration towards the anodal side. The expected responses for other configurations of GVS are also described. The model appears consistent with published data on the ocular and postural responses to GVS, and suggests other testable hypotheses concerning postural, ocular and perceptual responses to GVS.

  11. Transcranial brain stimulation: closing the loop between brain and stimulation

    PubMed Central

    Karabanov, Anke; Thielscher, Axel; Siebner, Hartwig Roman

    2016-01-01

    Purpose of review To discuss recent strategies for boosting the efficacy of noninvasive transcranial brain stimulation to improve human brain function. Recent findings Recent research exposed substantial intra- and inter-individual variability in response to plasticity-inducing transcranial brain stimulation. Trait-related and state-related determinants contribute to this variability, challenging the standard approach to apply stimulation in a rigid, one-size-fits-all fashion. Several strategies have been identified to reduce variability and maximize the plasticity-inducing effects of noninvasive transcranial brain stimulation. Priming interventions or paired associative stimulation can be used to ‘standardize’ the brain-state and hereby, homogenize the group response to stimulation. Neuroanatomical and neurochemical profiling based on magnetic resonance imaging and spectroscopy can capture trait-related and state-related variability. Fluctuations in brain-states can be traced online with functional brain imaging and inform the timing or other settings of transcranial brain stimulation. State-informed open-loop stimulation is aligned to the expression of a predefined brain state, according to prespecified rules. In contrast, adaptive closed-loop stimulation dynamically adjusts stimulation settings based on the occurrence of stimulation-induced state changes. Summary Approaches that take into account trait-related and state-related determinants of stimulation-induced plasticity bear considerable potential to establish noninvasive transcranial brain stimulation as interventional therapeutic tool. PMID:27224087

  12. 21 CFR 177.1360 - Ethylene-vinyl acetate-vinyl alcohol copolymers.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ethylene-vinyl acetate-vinyl alcohol copolymers... acetate-vinyl alcohol copolymers. Ethylene-vinyl acetate-vinyl alcohol copolymers (CAS Reg. No. 26221-27-2... accordance with the following prescribed conditions: (a) Ethylene-vinyl acetate-vinyl alcohol copolymers...

  13. 21 CFR 177.1360 - Ethylene-vinyl acetate-vinyl alcohol copolymers.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethylene-vinyl acetate-vinyl alcohol copolymers... acetate-vinyl alcohol copolymers. Ethylene-vinyl acetate-vinyl alcohol copolymers (CAS Reg. No. 26221-27-2... accordance with the following prescribed conditions: (a) Ethylene-vinyl acetate-vinyl alcohol copolymers...

  14. 21 CFR 177.1360 - Ethylene-vinyl acetate-vinyl alcohol copolymers.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Ethylene-vinyl acetate-vinyl alcohol copolymers... acetate-vinyl alcohol copolymers. Ethylene-vinyl acetate-vinyl alcohol copolymers (CAS Reg. No. 26221-27-2... accordance with the following prescribed conditions: (a) Ethylene-vinyl acetate-vinyl alcohol copolymers...

  15. 21 CFR 177.1360 - Ethylene-vinyl acetate-vinyl alcohol copolymers.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ethylene-vinyl acetate-vinyl alcohol copolymers... acetate-vinyl alcohol copolymers. Ethylene-vinyl acetate-vinyl alcohol copolymers (CAS Reg. No. 26221-27-2... accordance with the following prescribed conditions: (a) Ethylene-vinyl acetate-vinyl alcohol copolymers...

  16. 21 CFR 862.1390 - 5-Hydroxyindole acetic acid/serotonin test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false 5-Hydroxyindole acetic acid/serotonin test system... Test Systems § 862.1390 5-Hydroxyindole acetic acid/serotonin test system. (a) Identification. A 5-hydroxyindole acetic acid/serotonin test system is a device intended to measure 5-hydroxyindole acetic...

  17. 21 CFR 862.1390 - 5-Hydroxyindole acetic acid/serotonin test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false 5-Hydroxyindole acetic acid/serotonin test system... Test Systems § 862.1390 5-Hydroxyindole acetic acid/serotonin test system. (a) Identification. A 5-hydroxyindole acetic acid/serotonin test system is a device intended to measure 5-hydroxyindole acetic...

  18. 21 CFR 862.1390 - 5-Hydroxyindole acetic acid/serotonin test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false 5-Hydroxyindole acetic acid/serotonin test system... Test Systems § 862.1390 5-Hydroxyindole acetic acid/serotonin test system. (a) Identification. A 5-hydroxyindole acetic acid/serotonin test system is a device intended to measure 5-hydroxyindole acetic...

  19. 21 CFR 862.1390 - 5-Hydroxyindole acetic acid/serotonin test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false 5-Hydroxyindole acetic acid/serotonin test system... Test Systems § 862.1390 5-Hydroxyindole acetic acid/serotonin test system. (a) Identification. A 5-hydroxyindole acetic acid/serotonin test system is a device intended to measure 5-hydroxyindole acetic...

  20. The sensitizing potential of primary amyl acetate in the guinea pig.

    PubMed

    Ballantyne, B; Tyler, T R; Auletta, C S

    1986-06-01

    Primary amyl acetate is a liquid mixture of the isomeric forms of pentyl acetate, which is used as a volatile organic solvent. Because of the possibility for skin contact, primary amyl acetate was investigated for its potential to cause allergic contact dermatitis. Using a guinea pig maximization procedure, primary amyl acetate was found to be a possible marginal skin sensitizer. PMID:3727350