Science.gov

Sample records for acid ffa concentrations

  1. Short-chain free fatty acid receptors FFA2/GPR43 and FFA3/GPR41 as new potential therapeutic targets

    PubMed Central

    Ulven, Trond

    2012-01-01

    The deorphanization of the free fatty acid (FFA) receptors FFA1 (GPR40), FFA2 (GPR43), FFA3 (GPR41), GPR84, and GPR120 has made clear that the body is capable of recognizing and responding directly to nonesterified fatty acid of virtually any chain length. Colonic fermentation of dietary fiber produces high concentrations of the short-chain fatty acids (SCFAs) acetate, propionate and butyrate, a process which is important to health. The phylogenetically related 7-transmembrane (7TM) receptors free fatty acid receptor 2 (FFA2) and FFA3 are activated by these SCFAs, and several lines of evidence indicate that FFA2 and FFA3 mediate beneficial effects associated with a fiber-rich diet, and that they may be of interest as targets for treatment of inflammatory and metabolic diseases. FFA2 is highly expressed on immune cells, in particular neutrophils, and several studies suggest that the receptor plays a role in diseases involving a dysfunctional neutrophil response, such as inflammatory bowel disease (IBD). Both FFA2 and FFA3 have been implicated in metabolic diseases such as type 2 diabetes and in regulation of appetite. More research is however required to clarify the potential of the receptors as drug targets and establish if activation or inhibition would be the preferred mode of action. The availability of potent and selective receptor modulators is a prerequisite for these studies. The few modulators of FFA2 or FFA3 that have been published hitherto in the peer-reviewed literature in general have properties that make them less than ideal as such tools, but published patent applications indicate that better tool compounds might soon become available which should enable studies critical to validate the receptors as new drug targets. PMID:23060857

  2. Selective Orthosteric Free Fatty Acid Receptor 2 (FFA2) Agonists

    PubMed Central

    Schmidt, Johannes; Smith, Nicola J.; Christiansen, Elisabeth; Tikhonova, Irina G.; Grundmann, Manuel; Hudson, Brian D.; Ward, Richard J.; Drewke, Christel; Milligan, Graeme; Kostenis, Evi; Ulven, Trond

    2011-01-01

    Free fatty acid receptor 2 (FFA2; GPR43) is a G protein-coupled seven-transmembrane receptor for short-chain fatty acids (SCFAs) that is implicated in inflammatory and metabolic disorders. The SCFA propionate has close to optimal ligand efficiency for FFA2 and can hence be considered as highly potent given its size. Propionate, however, does not discriminate between FFA2 and the closely related receptor FFA3 (GPR41). To identify FFA2-selective ligands and understand the molecular basis for FFA2 selectivity, a targeted library of small carboxylic acids was examined using holistic, label-free dynamic mass redistribution technology for primary screening and the receptor-proximal G protein [35S]guanosine 5′-(3-O-thio)triphosphate activation, inositol phosphate, and cAMP accumulation assays for hit confirmation. Structure-activity relationship analysis allowed formulation of a general rule to predict selectivity for small carboxylic acids at the orthosteric binding site where ligands with substituted sp3-hybridized α-carbons preferentially activate FFA3, whereas ligands with sp2- or sp-hybridized α-carbons prefer FFA2. The orthosteric binding mode was verified by site-directed mutagenesis: replacement of orthosteric site arginine residues by alanine in FFA2 prevented ligand binding, and molecular modeling predicted the detailed mode of binding. Based on this, selective mutation of three residues to their non-conserved counterparts in FFA3 was sufficient to transfer FFA3 selectivity to FFA2. Thus, selective activation of FFA2 via the orthosteric site is achievable with rather small ligands, a finding with significant implications for the rational design of therapeutic compounds selectively targeting the SCFA receptors. PMID:21220428

  3. Adiponectin concentrations increase during acute FFA elevation in humans treated with rosiglitazone.

    PubMed

    Krzyzanowska, K; Mittermayer, F; Krugluger, W; Roden, M; Schernthaner, G; Wolzt, M

    2007-10-01

    The adipocytokine adiponectin is released by adipocytes upon activation of the peroxisome proliferator-activated receptor gamma (PPAR gamma). PPAR gamma has binding sites for thiazolidinediones and free fatty acids (FFAs). To evaluate if adiponectin serum concentrations are synergistically regulated by FFAs and thiazolidinediones IN VIVO plasma FFAs were acutely elevated in healthy subjects pre-treated with rosiglitazone or placebo. Sixteen healthy male subjects (23-37 years) were included in this double-blind, randomized, placebo-controlled parallel-group study. Rosiglitazone 8 mg or placebo was administered daily for 21 days. On the last day plasma FFA concentrations were increased by an intravenous triglyceride/heparin infusion. Blood for determination of adiponectin, C-reactive protein (CRP), leptin, resistin, FFAs, glucose, and insulin was drawn at baseline and on day 21 before and after 5 hours of triglyceride/heparin infusion. Adiponectin concentrations increased and FFA levels decreased in subjects receiving rosiglitazone (all p<0.05 VS. baseline). Lipid infusion significantly increased FFA plasma concentrations, with an attenuated elevation in rosiglitazone-treated subjects. However, adiponectin concentrations were only increased in subjects on rosiglitazone (p=0.018 VS. before lipid infusion), but not in controls. Leptin increased during lipid infusion in subjects receiving placebo but not in those on rosiglitazone. CRP and resistin were not affected by rosiglitazone or FFAs. The acute increase in circulating adiponectin concentrations during acutely elevated FFA depends on PPAR gamma activation in healthy subjects.

  4. Effects of Acute Supramaximal Cycle Exercise on Plasma FFA Concentration in Obese Adolescent Boys

    PubMed Central

    Jabbour, Georges

    2015-01-01

    Aims The aims of the present study are 1) to evaluate the free fatty acid (FFA) profile and 2) to determine the relative anaerobic and aerobic contributions to total energy consumption during repeated supramaximal cycling bouts (SCE) in adolescent boys with different body weight statuses. Materials and Methods Normal-weight (NW), overweight (OW), and obese (OB) adolescent boys (n =15 per group) completed a SCE sessions consisted of 6 x 6s maximal sprints with 2 min of passive rest between each repetition. Plasma FFA levels were determined at rest, immediately after a 10 min warm-up, and immediately at the end of SCE. The anaerobic and aerobic contributions (%) were measured via repeated SCE bouts. Insulin resistance was calculated using the homoeostatic model assessment (HOMA-IR) index. Results The FFA concentrations measured immediately after SCE were higher in the OB group than in the OW and NW (p<0.01 and p<0.01, respectively) groups. Moreover, the anaerobic contributions to SCE were significantly lower in obese adolescents (p<0.01) and decreased significantly during the 2nd, 3rd and 4th repetitions. The FFA levels were significantly associated with the HOMA-IR index and aerobic contribution among adolescent boys (r=0.83 and r=0.91, respectively, p<0.01). Conclusion In contrast to the NW and OW groups, there is an increase in lipid mobilization and sift to aerobic energy metabolism during SCE in the OB group. PMID:26076464

  5. [Profile of free fatty acids (FFA) in serum of young Colombians with obesity and metabolic syndrome].

    PubMed

    Bermudez, J A; Velásquez, C M

    2014-12-01

    Obesity produces greater circulation of free fatty acids (FFA). In adults, the FFA composition changes in states of obesity; in adolescents, the results are contradictory. This study compare the FFA profile of obese youth with and without Metabolic Syndrome (MetS) and explore the association between FFA and metabolic alterations of obesity and MetS. A cross-sectional study with 96 young people between 10 and 18 years old was divided into three groups: 1) obese youth with MetS, 2) obese youth without MetS; and 3) adequate weight (AW), matched according to age, gender, pubertal maturation and socioeconomic stratum. The nutritional status was classified according to the body-mass index (BMI), according to the World Health Organization 2007 (WHO, 2007); the waist circumference (WC), adiposity, lipid profile, highly-sensitive reactive C protein (hsRCP), glucose, insulin and insulin resistance (IR), according to the homeostatic model assessment (HOMA Calculator Version 2.2.2). The FFA serum concentration was determined by gas chromatography. Both obese groups had higher adiposity, inflamation (hsRCP), FFA totals and frequency palmitoleic-16:Jn7, compared to AW. The obese with MetS presented more metabolic alterations, a greater amount of dihomo-γ-linolenic (DHGL-20:3n6) and a 20:3n6/18:2n6 relation, indicative of increased activity of A6 desaturase (D6D). The FFA totals, palmitoleic-l6:1n7, DHGL-20:3n6, D6D activity and hsRCP significantly correlated with variables of adiposity, IR and triglicerides. The results in obese with MetS corroborate the association among central obesity, inflammation and increased lipolysis in visceral adipose tissue and metabolic alterations.

  6. Identification of diarylsulfonamides as agonists of the free fatty acid receptor 4 (FFA4/GPR120).

    PubMed

    Sparks, Steven M; Chen, Grace; Collins, Jon L; Danger, Dana; Dock, Steven T; Jayawickreme, Channa; Jenkinson, Stephen; Laudeman, Christopher; Leesnitzer, M Anthony; Liang, Xi; Maloney, Patrick; McCoy, David C; Moncol, David; Rash, Vincent; Rimele, Thomas; Vulimiri, Padmaja; Way, James M; Ross, Sean

    2014-07-15

    The exploration of a diarylsulfonamide series of free fatty acid receptor 4 (FFA4/GPR120) agonists is described. This work led to the identification of selective FFA4 agonist 8 (GSK137647A) and selective FFA4 antagonist 39. The in vitro profile of compounds 8 and 39 is presented herein.

  7. Extracellular Ionic Locks Determine Variation in Constitutive Activity and Ligand Potency between Species Orthologs of the Free Fatty Acid Receptors FFA2 and FFA3*

    PubMed Central

    Hudson, Brian D.; Tikhonova, Irina G.; Pandey, Sunil K.; Ulven, Trond; Milligan, Graeme

    2012-01-01

    Free fatty acid receptors 2 and 3 (FFA2 and FFA3) are G protein-coupled receptors for short chain free fatty acids (SCFAs). They respond to the same set of endogenous ligands but with distinct rank-order of potency such that acetate (C2) has been described as FFA2-selective, whereas propionate (C3) is non-selective. Although C2 was confirmed to be selective for human FFA2 over FFA3, this ligand was not selective between the mouse orthologs. Moreover, although C3 was indeed not selective between the human orthologs, it displayed clear selectivity for mouse FFA3 over mouse FFA2. This altered selectivity to C2 and C3 resulted from broad differences in SCFAs potency at the mouse orthologs. In studies to define the molecular basis for these observations, marked variation in ligand-independent constitutive activity was identified using a [35S]GTPγS assay. The orthologs with higher potency for the SCFAs, human FFA2 and mouse FFA3, displayed high constitutive activity in this assay, whereas the orthologs with lower potency for the agonist ligands, mouse FFA2 and human FFA3, did not. Sequence alignments of the second extracellular loop identified single negatively charged residues in FFA2 and FFA3 not conserved between species and predicted to form ionic lock interactions with arginine residues within the FFA2 or FFA3 agonist binding pocket to regulate constitutive activity and SCFA potency. Reciprocal mutation of these residues between species orthologs resulted in the induction (or repression) of constitutive activity and in most cases also yielded corresponding changes in SCFA potency. PMID:23066016

  8. Conjugated Linoleic Acids Mediate Insulin Release through Islet G Protein-coupled Receptor FFA1/GPR40*

    PubMed Central

    Schmidt, Johannes; Liebscher, Kathrin; Merten, Nicole; Grundmann, Manuel; Mielenz, Manfred; Sauerwein, Helga; Christiansen, Elisabeth; Due-Hansen, Maria E.; Ulven, Trond; Ullrich, Susanne; Gomeza, Jesús; Drewke, Christel; Kostenis, Evi

    2011-01-01

    Among dietary components, conjugated linoleic acids (CLAs) have attracted considerable attention as weight loss supplements in the Western world because they reduce fat stores and increase muscle mass. However, a number of adverse effects are also ascribed to the intake of CLAs such as aggravation of insulin resistance and the risk of developing diabetes. However, the mechanisms accounting for the effects of CLAs on glucose homeostasis are incompletely understood. Herein we provide evidence that CLAs specifically activate the cell surface receptor FFA1, an emerging therapeutic target to treat type 2 diabetes. Using different recombinant cellular systems engineered to stably express FFA1 and a set of diverse functional assays including the novel, label-free non-invasive dynamic mass redistribution technology (Corning® Epic® biosensor), both CLA isomers cis-9, trans-11-CLA and trans-10, cis-12-CLA were found to activate FFA1 in vitro at concentrations sufficient to also account for FFA1 activation in vivo. Each CLA isomer markedly increased glucose-stimulated insulin secretion in insulin-producing INS-1E cells that endogenously express FFA1 and in primary pancreatic β-cells of wild type but not FFA1−/− knock-out mice. Our findings establish a clear mechanistic link between CLAs and insulin production and identify the cell surface receptor FFA1 as a molecular target for CLAs, explaining their acute stimulatory effects on insulin secretion in vivo. CLAs are also revealed as insulinotropic components in widely used nutraceuticals, a finding with significant implication for development of FFA1 modulators to treat type 2 diabetes. PMID:21339298

  9. Effects of arachidonic acid on FFA4 receptor: Signaling, phosphorylation and internalization.

    PubMed

    Villegas-Comonfort, S; Takei, Y; Tsujimoto, G; Hirasawa, A; García-Sáinz, J A

    2017-02-01

    Arachidonic acid increased intracellular calcium, in cells expressing green fluorescent protein-tagged human FFA4 receptors, with an EC50 of ~40µM. This action was not blocked by cyclooxygenase or lipoxigenase inhibitors but it was inhibited by AH7614, a FFA4 antagonist. Arachidonic acid induced ERK activation accompanied by EGF receptor transactivation. However, EGF transactivation was not the major mechanism through which the fatty acid induced ERK phosphorylation, as evidenced by the inability of AG1478 to block it. Arachidonic acid increased FFA4 receptor phosphorylation that reached its maximum within 15min with an EC50 of ~30µM; inhibitors of protein kinase C partially diminish this effect and AH7614 blocked it. Arachidonic acid induced rapid and sustained Akt/PKB phosphorylation and FFA4 - β-arrestin interaction. Confocal microscopy evidenced that FFA4 receptor activation and phosphorylation were associated to internalization. In conclusion, arachidonic acid is a bona fide FFA4 receptor agonist.

  10. Omega-3 polyunsaturated fatty acids accelerate airway repair by activating FFA4 in club cells.

    PubMed

    Lee, Kyoung-Pil; Park, Soo-Jin; Kang, Saeromi; Koh, Jung-Min; Sato, Koichi; Chung, Hae Young; Okajima, Fumikazu; Im, Dong-Soon

    2017-03-17

    A GPCR named FFA4 (also known as GPR120) was found to act as a GPCR for omega-3 polyunsaturated fatty acids. Its expression has been reported in lung epithelial club cells. The authors investigated whether supplementation of the omega-3 fatty acids benefits lung health. Omacor® (7.75 mg kg-1), clinically prescribed preparation of omega-3 fatty acids and FFA4-knockout mice were utilized in a naphthalene-induced mouse model of acute airway injury (one injection of 30 mg kg-1, i.p.). Naphthalene injection induced complete destruction of bronchiolar epithelial cells within a day. Appearance of bronchiolar epithelial cells was observed after 21 days in control mice. It was found, however, that supplementation of omacor accelerated the recovery. The appearance of bronchiolar epithelial cells was observed between 7 and 14 days after naphthalene injury in omacor-treated mice. In isolated club cells, omega-3 fatty acids were found to stimulate cell proliferation and migration but to inhibit cell differentiation. Using pharmacological tools and FFA4-knockout mice, FFA4 was found to be responsible for omega-3 fatty acids-induced proliferation in vitro in club cells. Furthermore, accelerated recovery from naphthalene-induced airway injury in omacor-treated mice was not observed in FFA4-knockout mice in vivo. Present findings indicate that omega-3 fatty acids-induced proliferation of bronchiole epithelial cells through FFA4 is responsible for omacor-induced accelerated recovery from airway injury. Therefore, intermittent administration of omacor needs to be tested for acute airway injury, because omega-3 fatty acids stimulate proliferation but inhibits differentiation of club cells.

  11. The Molecular Basis of Ligand Interaction at Free Fatty Acid Receptor 4 (FFA4/GPR120)*

    PubMed Central

    Hudson, Brian D.; Shimpukade, Bharat; Milligan, Graeme; Ulven, Trond

    2014-01-01

    The long-chain fatty acid receptor FFA4 (previously GPR120) is receiving substantial interest as a novel target for the treatment of metabolic and inflammatory disease. This study examines for the first time the detailed mode of binding of both long-chain fatty acid and synthetic agonist ligands at FFA4 by integrating molecular modeling, receptor mutagenesis, and ligand structure-activity relationship approaches in an iterative format. In doing so, residues required for binding of fatty acid and synthetic agonists to FFA4 have been identified. This has allowed for the refinement of a well validated model of the mode of ligand-FFA4 interaction that will be invaluable in the identification of novel ligands and the future development of this receptor as a therapeutic target. The model reliably predicted the effects of substituent variations on agonist potency, and it was also able to predict the qualitative effect of binding site mutations in the majority of cases. PMID:24860101

  12. Omega-3 fatty acids and other FFA4 agonists inhibit growth factor signaling in human prostate cancer cells.

    PubMed

    Liu, Ze; Hopkins, Mandi M; Zhang, Zhihong; Quisenberry, Chrystal B; Fix, Louise C; Galvan, Brianna M; Meier, Kathryn E

    2015-02-01

    Omega-3 fatty acids (n-3 FAs) are proposed to have many beneficial effects on human health. However, the mechanisms underlying their potential cancer preventative effects are unclear. G protein-coupled receptors (GPCRs) of the free fatty acid receptor (FFAR) family, FFA1/GPR40 and FFA4/GPR120, specifically bind n-3 FAs as agonist ligands. In this study, we examined the effects of n-3 FAs in human prostate cancer cell lines. Initial studies established that the long-chain n-3 FAs, eicosapentaenoic acid (EPA) and docosahexaenoic acid, inhibit proliferation of DU145 cells in response to lysophosphatidic acid (LPA), a mitogenic lipid mediator. When added alone to serum-starved DU145 cells, EPA transiently activates signaling events, including p70S6K phosphorylation. However, when added 15 minutes prior to LPA, EPA suppresses LPA-induced activating phosphorylations of ERK, FAK, and p70S6K, and expression of the matricellular protein CCN1. The rapid onset of the inhibitory action of EPA suggested involvement of a GPCR. Further studies showed that DU145 and PC-3 cells express mRNA and protein for both FFA4 and FFA1. TUG-891 (4-[(4-fluoro-4'-methyl[1,1'-biphenyl]-2-yl)methoxy]-benzenepropanoic acid), a selective agonist for FFA4, exerts inhibitory effects on LPA- and epidermal growth factor-induced proliferation and migration, similar to EPA, in DU145 and PC-3 cells. The effects of TUG-891 and EPA are readily reversible. The FFA1/FFA4 agonist GW9508 (4-[[(3-phenoxyphenyl)methyl]amino]-benzenepropranoic acid) likewise inhibits proliferation at doses that block FFA4. Knockdown of FFA4 expression prevents EPA- and TUG-891-induced inhibition of growth and migration. Together, these results indicate that activation of FFA4 initiates signaling events that can inhibit growth factor-induced signaling, providing a novel mechanism for suppression of cancer cell proliferation.

  13. Liver free fatty acid (FFA) accumulation as an indicator of ischemic injury during cold preservation

    SciTech Connect

    Nemoto, E.M.; Kang, Y.; DeWolf, A.M.; Lin, M.R.; Bleyaert, A.L.; Winter, P.M.

    1987-05-01

    Reliable assessment of hepatic viability prior to harvest and transplant could improve graft success and aid in evaluating the efficacy of liver preservation techniques. Hepatic tissue metabolites, protein (Pr) synthesis, and ATP have been studied, but none reliably correlate with hepatic viability. Therefore, they studied changes in liver FFA relative to changes in ATP and Pr synthesis during cold ischemic preservation. Rats mechanically ventilated on 0.5% isoflurane/70% N/sub 2/O/30% O/sub 2/ were heparinized and their livers perfused with air-equilibrated Euro-Collins solution (ECS) at 0-4/sup 0/C and kept on ice. A piece of the liver was removed after 0, 2, 6, 8, 12, 24, 36 and 48 h of preservation for ATP and FFA analysis. A portion of the liver was sliced (250 ..mu..m thick) and incubated in vitro for /sup 14/C-lysine incorporation in albumin. ATP, FFA and Pr synthesis were unchanged in the first 8 h, but markedly decreased between 8 and 12 h with little change thereafter. In contrast, between 8 and 48 h, arachidonic and stearic acids increased by 5 and 2-fold, respectively. Changes in ATP and Pr synthesis correlate with the empirically derived clinical maximum of 8 to 12 h preservation. FFA accumulation appears to reflect hepatic ischemic injury and may be a means of evaluating the quality of a donor liver.

  14. Dietary Fatty Acids and Their Potential for Controlling Metabolic Diseases Through Activation of FFA4/GPR120.

    PubMed

    Ulven, Trond; Christiansen, Elisabeth

    2015-01-01

    It is well known that the amount and type of ingested fat impacts the development of obesity and metabolic diseases, but the potential for beneficial effects from fat has received less attention. It is becoming clear that the composition of the individual fatty acids in diet is important. Besides acting as precursors of potent signaling molecules, dietary fatty acids act directly on intracellular and cell surface receptors. The free fatty acid receptor 4 (FFA4, previously GPR120) is linked to the regulation of body weight, inflammation, and insulin resistance and represents a potential target for the treatment of metabolic disorders, including type 2 diabetes and obesity. In this review, we discuss the various types of dietary fatty acids, the link between FFA4 and metabolic diseases, the potential effects of the individual fatty acids on health, and the ability of fatty acids to activate FFA4. We also discuss the possibility of dietary schemes that implement activation of FFA4.

  15. Structure−Activity Study of Dihydrocinnamic Acids and Discovery of the Potent FFA1 (GPR40) Agonist TUG-469

    PubMed Central

    2010-01-01

    The free fatty acid 1 receptor (FFA1 or GPR40), which is highly expressed on pancreatic β-cells and amplifies glucose-stimulated insulin secretion, has emerged as an attractive target for the treatment of type 2 diabetes. Several FFA1 agonists containing the para-substituted dihydrocinnamic acid moiety are known. We here present a structure−activity relationship study of this compound family suggesting that the central methyleneoxy linker is preferable for the smaller compounds, whereas the central methyleneamine linker gives higher potency to the larger compounds. The study resulted in the discovery of the potent and selective full FFA1 agonist TUG-469 (29). PMID:24900217

  16. Defining the Molecular Basis for the First Potent and Selective Orthosteric Agonists of the FFA2 Free Fatty Acid Receptor*

    PubMed Central

    Hudson, Brian D.; Due-Hansen, Maria E.; Christiansen, Elisabeth; Hansen, Anna Mette; Mackenzie, Amanda E.; Murdoch, Hannah; Pandey, Sunil K.; Ward, Richard J.; Marquez, Rudi; Tikhonova, Irina G.; Ulven, Trond; Milligan, Graeme

    2013-01-01

    FFA2 is a G protein-coupled receptor that responds to short chain fatty acids and has generated interest as a therapeutic target for metabolic and inflammatory conditions. However, definition of its functions has been slowed by a dearth of selective ligands that can distinguish it from the closely related FFA3. At present, the only selective ligands described for FFA2 suffer from poor potency, altered signaling due to allosteric modes of action, or a lack of function at non-human orthologs of the receptor. To address the need for novel selective ligands, we synthesized two compounds potentially having FFA2 activity and examined the molecular basis of their function. These compounds were confirmed to be potent and selective orthosteric FFA2 agonists. A combination of ligand structure-activity relationship, pharmacological analysis, homology modeling, species ortholog comparisons, and mutagenesis studies were then employed to define the molecular basis of selectivity and function of these ligands. From this, we identified key residues within both extracellular loop 2 and the transmembrane domain regions of FFA2 critical for ligand function. One of these ligands was active with reasonable potency at rodent orthologs of FFA2 and demonstrated the role of FFA2 in inhibition of lipolysis and glucagon-like peptide-1 secretion in murine-derived 3T3-L1 and STC-1 cell lines, respectively. Together, these findings describe the first potent and selective FFA2 orthosteric agonists and demonstrate key aspects of ligand interaction within the binding site of FFA2 that will be invaluable in future ligand development at this receptor. PMID:23589301

  17. A New Pain Regulatory System via the Brain Long Chain Fatty Acid Receptor GPR40/FFA1 Signal.

    PubMed

    Nakamoto, Kazuo

    2017-01-01

     An increasingly large number of pharmacological and physiological works on fatty acids have shown that the functional properties of fatty acids are regulated by the amount of individual fatty acid intake and the distribution of fatty acids among organs. Recently, it has been determined that G-protein-coupled receptor 40/free fatty acid receptor 1 (GPR40/FFA1) is activated by long-chain fatty acids, such as docosahexaenoic acid (DHA). GPR40/FFA1 is mainly expressed in the β cell of the pancreas, spinal cord and brain. It is reported that this receptor has a functional role in controlling blood glucose levels via the modulation of insulin secretion. However, its physiological function in the brain remains unknown. Our previous studies have shown that GPR40/FFA1 is expressed in pro-opiomelanocortin (POMC)-positive neurons of the arcuate nucleus, serotonergic neurons in the nucleus raphe magnus, and in noradrenergic neurons in the locus coeruleus. Furthermore, the intracerebroventricular injection of DHA or GW9508, which is a selective GPR40/FFA1 agonist, attenuates formalin-induced inflammatory pain behavior through increasing β-endorphin release in the hypothalamus. It also suppresses complete Freund's adjuvant-induced mechanical allodynia and thermal hyperalgesia. Our findings suggest that brain free long-chain fatty acids-GPR40/FFA1 signaling might have an important role in the modulation of endogenous pain control systems. In this review, I discuss the current status and our recent study regarding a new pain regulatory system via the brain long chain fatty acid receptor GPR40/FFA1 signal.

  18. FFA Contests

    ERIC Educational Resources Information Center

    Schumann, Herbert

    1977-01-01

    A teacher educator gives reasons why the vocational agriculture teacher should become involved in preparing his students for Future Farmers of America (FFA) contests and some steps and precautions he should take to successfully integrate FFA contests into the instructional program. (MF)

  19. The short-chain fatty acid receptor, FFA2, contributes to gestational glucose homeostasis.

    PubMed

    Fuller, Miles; Priyadarshini, Medha; Gibbons, Sean M; Angueira, Anthony R; Brodsky, Michael; Hayes, M Geoffrey; Kovatcheva-Datchary, Petia; Bäckhed, Fredrik; Gilbert, Jack A; Lowe, William L; Layden, Brian T

    2015-11-15

    The structure of the human gastrointestinal microbiota can change during pregnancy, which may influence gestational metabolism; however, a mechanism of action remains unclear. Here we observed that in wild-type (WT) mice the relative abundance of Actinobacteria and Bacteroidetes increased during pregnancy. Along with these changes, short-chain fatty acids (SCFAs), which are mainly produced through gut microbiota fermentation, significantly changed in both the cecum and peripheral blood throughout gestation in these mice. SCFAs are recognized by G protein-coupled receptors (GPCRs) such as free fatty acid receptor-2 (FFA2), and we have previously demonstrated that the fatty acid receptor-2 gene (Ffar2) expression is higher in pancreatic islets during pregnancy. Using female Ffar2-/- mice, we explored the physiological relevance of signaling through this GPCR and found that Ffar2-deficient female mice developed fasting hyperglycemia and impaired glucose tolerance in the setting of impaired insulin secretion compared with WT mice during, but not before, pregnancy. Insulin tolerance tests were similar in Ffar2-/- and WT mice before and during pregnancy. Next, we examined the role of FFA2 in gestational β-cell mass, observing that Ffar2-/- mice had diminished gestational expansion of β-cells during pregnancy. Interestingly, mouse genotype had no significant impact on the composition of the gut microbiome, but did affect the observed SCFA profiles, suggesting a functional difference in the microbiota. Together, these results suggest a potential link between increased Ffar2 expression in islets and the alteration of circulating SCFA levels, possibly explaining how changes in the gut microbiome contribute to gestational glucose homeostasis.

  20. The short chain fatty acid receptor, FFA2, contributes to gestational glucose homeostasis

    DOE PAGES

    Fuller, Miles; Priyadarshini, Medha; Gibbons, Sean M.; ...

    2015-09-22

    The structure of the human gastrointestinal microbiota can change during pregnancy, which may influence gestational metabolism; however, a mechanism of action remains unclear. Here we observed that in wild-type (WT) mice the relative abundance of Actinobacteria and Bacteroidetes increased during pregnancy. Along with these changes, short-chain fatty acids (SCFAs), which are mainly produced through gut microbiota fermentation, significantly changed in both the cecum and peripheral blood throughout gestation in these mice. SCFAs are recognized by G protein-coupled receptors (GPCRs) such as free fatty acid receptor-2 (FFA2), and we have previously demonstrated that the fatty acid receptor-2 gene (Ffar2) expression ismore » higher in pancreatic islets during pregnancy. Using female Ffar2-/- mice, we explored the physiological relevance of signaling through this GPCR and found that Ffar2-deficient female mice developed fasting hyperglycemia and impaired glucose tolerance in the setting of impaired insulin secretion compared with WT mice during, but not before, pregnancy. Insulin tolerance tests were similar in Ffar2-/- and WT mice before and during pregnancy. Next, we examined the role of FFA2 in gestational β-cell mass, observing that Ffar2-/- mice had diminished gestational expansion of β-cells during pregnancy. Interestingly, mouse genotype had no significant impact on the composition of the gut microbiome, but did affect the observed SCFA profiles, suggesting a functional difference in the microbiota. Altogether, these results suggest a potential link between increased Ffar2 expression in islets and the alteration of circulating SCFA levels, possibly explaining how changes in the gut microbiome contribute to gestational glucose homeostasis.« less

  1. The short chain fatty acid receptor, FFA2, contributes to gestational glucose homeostasis

    SciTech Connect

    Fuller, Miles; Priyadarshini, Medha; Gibbons, Sean M.; Angueira, Anthony R.; Brodsky, Michael; Hayes, M. Geoffrey; Kovatcheva-Datchary, Petia; Backhed, Fredrik; Gilbert, Jack A.; Lowe, Jr., William L.; Layden, Brian T.

    2015-09-22

    The structure of the human gastrointestinal microbiota can change during pregnancy, which may influence gestational metabolism; however, a mechanism of action remains unclear. Here we observed that in wild-type (WT) mice the relative abundance of Actinobacteria and Bacteroidetes increased during pregnancy. Along with these changes, short-chain fatty acids (SCFAs), which are mainly produced through gut microbiota fermentation, significantly changed in both the cecum and peripheral blood throughout gestation in these mice. SCFAs are recognized by G protein-coupled receptors (GPCRs) such as free fatty acid receptor-2 (FFA2), and we have previously demonstrated that the fatty acid receptor-2 gene (Ffar2) expression is higher in pancreatic islets during pregnancy. Using female Ffar2-/- mice, we explored the physiological relevance of signaling through this GPCR and found that Ffar2-deficient female mice developed fasting hyperglycemia and impaired glucose tolerance in the setting of impaired insulin secretion compared with WT mice during, but not before, pregnancy. Insulin tolerance tests were similar in Ffar2-/- and WT mice before and during pregnancy. Next, we examined the role of FFA2 in gestational β-cell mass, observing that Ffar2-/- mice had diminished gestational expansion of β-cells during pregnancy. Interestingly, mouse genotype had no significant impact on the composition of the gut microbiome, but did affect the observed SCFA profiles, suggesting a functional difference in the microbiota. Altogether, these results suggest a potential link between increased Ffar2 expression in islets and the alteration of circulating SCFA levels, possibly explaining how changes in the gut microbiome contribute to gestational glucose homeostasis.

  2. Concomitant Action of Structural Elements and Receptor Phosphorylation Determines Arrestin-3 Interaction with the Free Fatty Acid Receptor FFA4*

    PubMed Central

    Butcher, Adrian J.; Hudson, Brian D.; Shimpukade, Bharat; Alvarez-Curto, Elisa; Prihandoko, Rudi; Ulven, Trond; Milligan, Graeme; Tobin, Andrew B.

    2014-01-01

    In addition to being nutrients, free fatty acids act as signaling molecules by activating a family of G protein-coupled receptors. Among these is FFA4, previously called GPR120, which responds to medium and long chain fatty acids, including health-promoting ω-3 fatty acids, which have been implicated in the regulation of metabolic and inflammatory responses. Here we show, using mass spectrometry, mutagenesis, and phosphospecific antibodies, that agonist-regulated phosphorylation of the human FFA4 receptor occurred primarily at five residues (Thr347, Thr349, Ser350, Ser357, and Ser360) in the C-terminal tail. Mutation of these residues reduced both the efficacy and potency of ligand-mediated arrestin-3 recruitment as well as affecting recruitment kinetics. Combined mutagenesis of all five of these residues was insufficient to fully abrogate interaction with arrestin-3, but further mutagenesis of negatively charged residues revealed additional structural components for the interaction with arrestin-3 within the C-terminal tail of the receptor. These elements consist of the acidic residues Glu341, Asp348, and Asp355 located close to the phosphorylation sites. Receptor phosphorylation thus operates in concert with structural elements within the C-terminal tail of FFA4 to allow for the recruitment of arrestin-3. Importantly, these mechanisms of arrestin-3 recruitment operate independently from Gq/11 coupling, thereby offering the possibility that ligands showing stimulus bias could be developed that exploit these differential coupling mechanisms. Furthermore, this provides a strategy for the design of biased receptors to probe physiologically relevant signaling. PMID:24817122

  3. Discovery of TUG-770: A Highly Potent Free Fatty Acid Receptor 1 (FFA1/GPR40) Agonist for Treatment of Type 2 Diabetes

    PubMed Central

    2013-01-01

    Free fatty acid receptor 1 (FFA1 or GPR40) enhances glucose-stimulated insulin secretion from pancreatic β-cells and currently attracts high interest as a new target for the treatment of type 2 diabetes. We here report the discovery of a highly potent FFA1 agonist with favorable physicochemical and pharmacokinetic properties. The compound efficiently normalizes glucose tolerance in diet-induced obese mice, an effect that is fully sustained after 29 days of chronic dosing. PMID:23687558

  4. Free fatty acids do not acutely increase asymmetrical dimethylarginine concentrations.

    PubMed

    Namiranian, K; Mittermayer, F; Artwohl, M; Pleiner, J; Schaller, G; Mayer, B X; Bayerle-Eder, M; Roden, M; Baumgartner-Parzer, S; Wolzt, M

    2005-12-01

    Concentrations of asymmetrical dimethylarginine (ADMA) and free fatty acids (FFAs) are elevated in insulin resistance which is associated with impaired vascular function. We hypothesized that FFAs could alter vascular tone by affecting ADMA concentrations. Plasma FFA levels were increased in seventeen healthy male volunteers by Intralipid/heparin infusion; hemodynamic and biochemical parameters were measured after 90 minutes. Plasma collected before and during Intralipid/heparin or equivalent synthetic FFAs was incubated with human umbilical vein endothelial cells (HUVECs) in vitro. Intralipid/heparin infusion resulted in an approximately seven-fold increase in plasma FFA levels to 1861 +/- 139 micromol/l, which was paralleled by increased systemic blood pressure and forearm blood flow. Intralipid/heparin did not affect ADMA (baseline mean 0.59 [95 % confidence interval [CI]: 0.54; 0.64] and 0.56 [CI: 0.51; 0.59] after 90 minutes), but slightly decreased SDMA (from 0.76, [CI: 0.70; 0.83] to 0.71 [CI: 0.64; 0.74], p < 0.05), and had no effect on ADMA/SDMA ratio. There was no correlation between ADMA and FFA concentrations or forearm blood flow. Incubation of HUVECs with FFA-rich plasma or synthetic FFAs induced an ADMA release after 24 hours, but not after 90 minutes. Acutely increased FFA levels caused hemodynamic effects but did not affect ADMA. Prolonged elevation of FFA levels might influence vascular function by increasing ADMA levels.

  5. The Pharmacology of TUG-891, a Potent and Selective Agonist of the Free Fatty Acid Receptor 4 (FFA4/GPR120), Demonstrates Both Potential Opportunity and Possible Challenges to Therapeutic Agonism

    PubMed Central

    Hudson, Brian D.; Shimpukade, Bharat; Mackenzie, Amanda E.; Butcher, Adrian J.; Pediani, John D.; Christiansen, Elisabeth; Heathcote, Helen; Tobin, Andrew B.; Ulven, Trond

    2013-01-01

    TUG-891 [3-(4-((4-fluoro-4′-methyl-[1,1′-biphenyl]-2-yl)methoxy)phenyl)propanoic acid] was recently described as a potent and selective agonist for the long chain free fatty acid (LCFA) receptor 4 (FFA4; previously G protein–coupled receptor 120, or GPR120). Herein, we have used TUG-891 to further define the function of FFA4 and used this compound in proof of principle studies to indicate the therapeutic potential of this receptor. TUG-891 displayed similar signaling properties to the LCFA α-linolenic acid at human FFA4 across various assay end points, including stimulation of Ca2+ mobilization, β-arrestin-1 and β-arrestin-2 recruitment, and extracellular signal-regulated kinase phosphorylation. Activation of human FFA4 by TUG-891 also resulted in rapid phosphorylation and internalization of the receptor. While these latter events were associated with desensitization of the FFA4 signaling response, removal of TUG-891 allowed both rapid recycling of FFA4 back to the cell surface and resensitization of the FFA4 Ca2+ signaling response. TUG-891 was also a potent agonist of mouse FFA4, but it showed only limited selectivity over mouse FFA1, complicating its use in vivo in this species. Pharmacologic dissection of responses to TUG-891 in model murine cell systems indicated that activation of FFA4 was able to mimic many potentially beneficial therapeutic properties previously reported for LCFAs, including stimulating glucagon-like peptide-1 secretion from enteroendocrine cells, enhancing glucose uptake in 3T3-L1 adipocytes, and inhibiting release of proinflammatory mediators from RAW264.7 macrophages, which suggests promise for FFA4 as a therapeutic target for type 2 diabetes and obesity. Together, these results demonstrate both potential but also significant challenges that still need to be overcome to therapeutically target FFA4. PMID:23979972

  6. Effects of Increased Free Fatty Acid Availability on Adipose Tissue Fatty Acid Storage in Men

    PubMed Central

    Mundi, Manpreet S.; Koutsari, Chistina

    2014-01-01

    Context: A portion of free fatty acids (FFA) released from adipose tissue lipolysis are re-stored in adipocytes via direct uptake. Rates of direct adipose tissue FFA storage are much greater in women than men, but women also have greater systemic FFA flux and more body fat. Objective: We tested the hypotheses that experimental increases in FFA in men would equalize the rates of direct adipose tissue FFA storage in men and women. Design: We used a lipid emulsion infusion to raise FFA in men to levels seen in post-absorptive women. Direct FFA storage (μmol·kg fat−1·min−1) rates in abdominal and femoral fat was assessed using stable isotope tracer infusions to measure FFA disappearance rates and an iv FFA radiotracer bolus/timed biopsy. Setting: These studies were performed in a Clinical Research Center. Participants: Data from 13 non-obese women was compared with that from eight obese and eight non-obese men. Intervention: The men received a lipid emulsion infusion to raise FFA. Main Outcome Measures: We measured the rates of direct FFA storage in abdominal and femoral adipose tissue. Results: The three groups were similar in age and FFA flux by design; obese men had similar body fat percentage as non-obese women. Despite matching for FFA concentrations and flux, FFA storage per kg abdominal (P < .01) and femoral (P < .001) fat was less in both lean and obese men than in non-obese women. Abdominal FFA storage rates were correlated with proteins/enzymes in the FFA uptake/triglyceride synthesis pathway in men. Conclusion: The lesser rates of direct FFA adipose tissue in men compared with women cannot be explained by reduced FFA availability. PMID:25192251

  7. Insulin-Mediated FFA Suppression Is Associated with Triglyceridemia and Insulin Sensitivity Independent of Adiposity

    PubMed Central

    Bush, Nikki C.; Basu, Rita; Rizza, Robert A.; Nair, K. Sreekumaran; Khosla, Sundeep

    2012-01-01

    Context: A central/visceral fat distribution and excess free fatty acid (FFA) availability are associated with dyslipidemia and insulin resistance. However, these two characteristics often coexist, making it difficult to detect the independent contributions of each. Whether FFA suppression is more closely linked to metabolic abnormalities is not clear. Objective: The aim of the study was to examine the relationship between FFA suppression, body fat distribution, and fitness as contributors toward insulin resistance and hypertriglyceridemia. Design: We measured systemic palmitate turnover using an iv infusion of [9,10-3H]palmitate; upper body sc adipose tissue (UBSQ) and visceral adipose tissue (VAT) with dual-energy x-ray absorptiometry and a single-slice abdominal computed tomography scan; fitness with a graded exercise treadmill test; and insulin sensitivity with both the iv glucose tolerance test (IVGTT) (SIIVGTT) and mixed meal tolerance test (SIMeal). Setting: The study was conducted at a General Clinical Research Center. Participants: Baseline data were obtained from 140 elderly adults (age, 60–88 yr; 83 males) and 60 young adults (age, 18–31 yr; 31 males) who participated in a previously published trial assessing the effects of 2-yr supplementation of dehydroepiandrosterone or testosterone on body composition, glucose metabolism, and bone density. Interventions: There were no interventions. Main Outcome Measures: We measured fasting plasma triglyceride (TG) concentrations, SIIVGTT, and SIMeal. Results: Using multivariate regression analysis, the strongest combined predictors of TG concentrations were VAT, postmeal nadir FFA concentrations, sex, and age. The best predictors of SIIVGTT were IVGTT nadir palmitate concentration, VAT, UBSQ fat, fitness, and age, whereas the best predictors of SIMeal were meal nadir palmitate concentration, UBSQ fat, fitness, and sex. Conclusions: FFA suppression is associated with both fasting TG concentrations and insulin

  8. Prevocational Agribusiness and the FFA

    ERIC Educational Resources Information Center

    James, Kenneth A.

    1975-01-01

    The author discusses the development of the career education concept relating to agribusiness at the junior high and middle school level. In the prevocational agribusiness program, it is also effective to supplement the program with an FFA chapter. (JB)

  9. Sex Differences in Long Chain Fatty Acid Utilization and Fatty Acid Binding Protein Concentration in Rat Liver

    PubMed Central

    Ockner, Robert K.; Burnett, David A.; Lysenko, Nina; Manning, Joan A.

    1979-01-01

    Female sex and estrogen administration are associated with increased hepatic production of triglyceride-rich lipoproteins; the basis for this has not been fully elucidated. Inasmuch as hepatic lipoprotein production is also influenced by FFA availability and triglyceride biosynthesis, we investigated sex differences in FFA utilization in rat hepatocyte suspensions and in the components of the triglyceride biosynthetic pathway. Isolated adult rat hepatocyte suspensions were incubated with albumin-bound [14C]oleate for up to 15 min. At physiological and low oleate concentrations, cells from females incorporated significantly more 14C into glycerolipids, especially triglycerides, and into oxidation products than did male cells, per milligram cell protein. At 0.44 mM oleate, incorporation into triglycerides in female cells was approximately twice that in male cells. Comparable sex differences were observed in cells from fasted animals and when [14C]-glycerol incorporation was measured. At higher oleate concentrations, i.e., fatty acid:albumin mole ratios in excess of 2:1, these sex differences were no longer demonstrable, suggesting that maximal rates of fatty acid esterification and oxidation were similar in female and male cells. In female and male hepatic microsomes, specific activities of long chain acyl coenzyme A synthetase, phosphatidate phosphohydrolase, and diglyceride acyltransferase were similar, but glycerol-3-phosphate acyltransferase activity was slightly greater in females at certain substrate concentrations. Microsomal incorporation of [14C]oleate into total glycerolipids was not significantly greater in females. In further contrast to intact cells, microsomal incorporation of [14C]oleate into triglycerides, although significantly greater in female microsomes, accounted for only a small fraction of the fatty acid esterified. The binding affinity and stoichiometry of partially purified female hepatic fatty acid binding protein (FABP) were similar to

  10. Advising an Urban FFA Chapter: A Narrative of Two Urban FFA Advisors

    ERIC Educational Resources Information Center

    Martin, Michael J.; Kitchel, Tracy

    2015-01-01

    Advising an urban FFA chapter can be a challenge for urban agriculture teachers. The contextual differences between the rural-oriented FFA and urban FFA members can make bridging the gap difficult. This narrative study sought to explore how the urban context shapes the work of an FFA chapter from the perspectives of two FFA advisors at the same…

  11. Influence of FFA Activities on Critical Thinking Skills in Texas Three-Star FFA Chapters

    ERIC Educational Resources Information Center

    Latham, Lindsey; Rayfield, John; Moore, Lori L.

    2015-01-01

    The purpose of this study was to determine the relationship of FFA activities on critical thinking skills of Texas FFA members in three-star FFA chapters. This descriptive study was conducted in eight purposively selected three-star FFA chapters throughout Texas. Three-star chapters are those chapters who have emerged as outstanding programs…

  12. Examining Camper Learning Outcomes and Knowledge Retention at Oklahoma FFA Leadership Camp

    ERIC Educational Resources Information Center

    Brown, Nicholas R.; Terry, Robert, Jr.; Kelsey, Kathleen D.

    2014-01-01

    The National FFA Organization is committed to providing non-formal learning activities focusing on leadership education. Summer camps are a major component of FFA activities and concentrate on personal growth, leadership development, and recreational activities for youth. This repeated measures study determined the level of cognitive gain and the…

  13. The New FFA--Relevant, Flexible.

    ERIC Educational Resources Information Center

    Future Farmers of America, Washington, DC.

    To make education more relevant, the 1972 national seminar sought ways of integrating the Future Farmers of America (FFA) program with the broadened agricultural instruction program. Topics discussed included: (1) "Role of the FFA in the Changing Program of Agricultural Education" - William Gray (Moderator), (2) "But How Do We Get…

  14. Parliamentary Procedure for the FFA Member.

    ERIC Educational Resources Information Center

    Joestgen, John G.

    Information and examples concerning parliamentary procedures are presented in this instructional manual written for Wisconsin Future Farmers of America (FFA) members and FFA parliamentary procedure teams. Topics include the following: secretary minutes (bylaws, officers, quorum, order of business, meeting and session, introducing business,…

  15. Robust expertise effects in right FFA

    PubMed Central

    McGugin, Rankin Williams; Newton, Allen T; Gore, John C; Gauthier, Isabel

    2015-01-01

    The fusiform face area (FFA) is one of several areas in occipito-temporal cortex whose activity is correlated with perceptual expertise for objects. Here, we investigate the robustness of expertise effects in FFA and other areas to a strong task manipulation that increases both perceptual and attentional demands. With high-resolution fMRI at 7Telsa, we measured responses to images of cars, faces and a category globally visually similar to cars (sofas) in 26 subjects who varied in expertise with cars, in (a) a low load 1-back task with a single object category and (b) a high load task in which objects from two categories rapidly alternated and attention was required to both categories. The low load condition revealed several areas more active as a function of expertise, including both posterior and anterior portions of FFA bilaterally (FFA1/FFA2 respectively). Under high load, fewer areas were positively correlated with expertise and several areas were even negatively correlated, but the expertise effect in face-selective voxels in the anterior portion of FFA (FFA2) remained robust. Finally, we found that behavioral car expertise also predicted increased responses to sofa images but no behavioral advantages in sofa discrimination, suggesting that global shape similarity to a category of expertise is enough to elicit a response in FFA and other areas sensitive to experience, even when the category itself is not of special interest. The robustness of expertise effects in right FFA2 and the expertise effects driven by visual similarity both argue against attention being the sole determinant of expertise effects in extrastriate areas. PMID:25192631

  16. Robust expertise effects in right FFA.

    PubMed

    McGugin, Rankin Williams; Newton, Allen T; Gore, John C; Gauthier, Isabel

    2014-10-01

    The fusiform face area (FFA) is one of several areas in occipito-temporal cortex whose activity is correlated with perceptual expertise for objects. Here, we investigate the robustness of expertise effects in FFA and other areas to a strong task manipulation that increases both perceptual and attentional demands. With high-resolution fMRI at 7T, we measured responses to images of cars, faces and a category globally visually similar to cars (sofas) in 26 subjects who varied in expertise with cars, in (a) a low load 1-back task with a single object category and (b) a high load task in which objects from two categories were rapidly alternated and attention was required to both categories. The low load condition revealed several areas more active as a function of expertise, including both posterior and anterior portions of FFA bilaterally (FFA1/FFA2, respectively). Under high load, fewer areas were positively correlated with expertise and several areas were even negatively correlated, but the expertise effect in face-selective voxels in the anterior portion of FFA (FFA2) remained robust. Finally, we found that behavioral car expertise also predicted increased responses to sofa images but no behavioral advantages in sofa discrimination, suggesting that global shape similarity to a category of expertise is enough to elicit a response in FFA and other areas sensitive to experience, even when the category itself is not of special interest. The robustness of expertise effects in right FFA2 and the expertise effects driven by visual similarity both argue against attention being the sole determinant of expertise effects in extrastriate areas.

  17. Protective Effect of Unsaturated Fatty Acids on Palmitic Acid-Induced Toxicity in Skeletal Muscle Cells is not Mediated by PPARδ Activation.

    PubMed

    Tumova, Jana; Malisova, Lucia; Andel, Michal; Trnka, Jan

    2015-10-01

    Unsaturated free fatty acids (FFA) are able to prevent deleterious effects of saturated FFA in skeletal muscle cells although the mechanisms involved are still not completely understood. FFA act as endogenous ligands of peroxisome proliferator-activated receptors (PPAR), transcription factors regulating the expression of genes involved in lipid metabolism. The aim of this study was to determine whether activation of PPARδ, the most common PPAR subtype in skeletal muscle, plays a role in mediating the protective effect of unsaturated FFA on saturated FFA-induced damage in skeletal muscle cells and to examine an impact on mitochondrial respiration. Mouse C2C12 myotubes were treated for 24 h with different concentrations of saturated FFA (palmitic acid), unsaturated FFA (oleic, linoleic and α-linolenic acid), and their combinations. PPARδ agonist GW501516 and antagonist GSK0660 were also used. Both mono- and polyunsaturated FFA, but not GW501516, prevented palmitic acid-induced cell death. Mono- and polyunsaturated FFA proved to be effective activators of PPARδ compared to saturated palmitic acid; however, in combination with palmitic acid their effect on PPARδ activation was blocked and stayed at the levels observed for palmitic acid alone. Unsaturated FFA at moderate physiological concentrations as well as GW501516, but not palmitic acid, mildly uncoupled mitochondrial respiration. Our results indicate that although unsaturated FFA are effective activators of PPARδ, their protective effect on palmitic acid-induced toxicity is not mediated by PPARδ activation and subsequent induction of lipid regulatory genes in skeletal muscle cells. Other mechanisms, such as mitochondrial uncoupling, may underlie their effect.

  18. Improved Free Fatty Acid Production in Cyanobacteria with Synechococcus sp. PCC 7002 as Host

    PubMed Central

    Ruffing, Anne M.

    2014-01-01

    Microbial free fatty acids (FFAs) have been proposed as a potential feedstock for renewable energy. The ability to directly convert carbon dioxide into FFAs makes cyanobacteria ideal hosts for renewable FFA production. Previous metabolic engineering efforts using the cyanobacterial hosts Synechocystis sp. PCC 6803 and Synechococcus elongatus PCC 7942 have demonstrated this direct conversion of carbon dioxide into FFAs; however, FFA yields in these hosts are limited by the negative impact of FFA production on the host cell physiology. This work investigates the use of Synechococcus sp. PCC 7002 as a cyanobacterial host for FFA production. In comparison to S. elongatus PCC 7942, Synechococcus sp. PCC 7002 strains produced and excreted FFAs at similar concentrations but without the detrimental effects on host physiology. The enhanced tolerance to FFA production with Synechococcus sp. PCC 7002 was found to be temperature-dependent, with physiological effects such as reduced photosynthetic yield and decreased photosynthetic pigments observed at higher temperatures. Additional genetic manipulations were targeted for increased FFA production, including thioesterases and ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO). Overexpression of non-native RuBisCO subunits (rbcLS) from a psbAI promoter resulted in more than a threefold increase in FFA production, with excreted FFA concentrations reaching >130 mg/L. This work illustrates the importance of host strain selection for cyanobacterial biofuel production and demonstrates that the FFA tolerance of Synechococcus sp. PCC 7002 can allow for high yields of excreted FFA. PMID:25152890

  19. Factors Impacting Members Decision to Continue FFA beyond High School

    ERIC Educational Resources Information Center

    Sanok, Danielle E.; Stripling, Christopher T.; Stephens, Carrie A.; Griffith, Andrew P.

    2015-01-01

    The purpose of this study was to determine the factors influencing FFA members to continue their FFA experience beyond high school. Two focus groups were conducted, one for collegiate FFA members and one for past/current state officers. Participants provided several areas of improvement for collegiate and alumni FFA membership. Participants noted…

  20. Critical Theory View of the National FFA Convention

    ERIC Educational Resources Information Center

    Martin, Michael J.; Kitchel, Tracy

    2015-01-01

    Urban FFA members face unique challenges if they want to become active members in the National FFA Organization. FFA leaders have realized that the FFA organization does not represent the evolving demographics of America and have made efforts to cater to urban and diverse high school audiences with some success. This study seeks to explore this…

  1. Urban FFA Members' Sense of the Organizational Culture of the FFA

    ERIC Educational Resources Information Center

    Martin, Michael J.; Kitchel, Tracy

    2014-01-01

    Organizational culture shapes how members of a group act. The culture has the power to exclude potential new members who do not fit into the culture of the organization. Research on urban school-based agriculture programs has indicated that urban agriculture students face barriers to their participation in the National FFA Organization (FFA).…

  2. Depression of serum calcium by increased plasma free fatty acids in the rat: a mechanism for hypocalcemia in acute pancreatitis.

    PubMed

    Warshaw, A L; Lee, K H; Napier, T W; Fournier, P O; Duchainey, D; Axelrod, L

    1985-10-01

    Some patients with hypertriglyceridemia and acute pancreatitis have marked hypocalcemia and high levels of plasma free fatty acids (FFAs). This study tests the hypothesis that increased plasma FFAs can significantly reduce the calcium level in vivo, a phenomenon which is different from local formation of calcium soaps due to lipolysis of adipose tissue lipids. Free fatty acid elevation was induced in rats by the administration of heparin and by the infusion of triglycerides. The results show that, compared with controls, induction of elevated FFA (from 1.57 +/- 0.08 mEq/L to 5.64 +/- 0.35, mean +/- SEM) causes the concentration of calcium to fall rapidly (from 9.04 +/- 0.06 mg/dl to 8.42 +/- 0.10, p less than 0.001). There is a significant (p less than 0.001) positive correlation between spontaneous baseline concentration of FFA and the responsiveness of calcium concentration to FFA challenge. At near-normal levels of FFA there is a significant (p less than 0.001) correlation between the magnitude of increased FFA concentration and decreased calcium concentration. Additional studies in vivo and in vitro show that elevated plasma triglycerides per se did not interfere with measurement of calcium concentration; however, FFA-albumin complexes bind calcium and lower its measured value. These findings suggest that (a) changes in the concentration of FFA occurring spontaneously may affect measured serum calcium concentration; (b) the observed depression of serum calcium concentration may be due in part to intravascular sequestration of calcium by FFA, but increased flux of circulating calcium-FFA complexes into extravascular and intracellular sites may also be important; (c) the markedly increased FFA concentration in some patients with acute pancreatitis may contribute significantly to hypocalcemia and calcium flux in these patients. As parathyroid hormone secretion, function, or integrity may be impaired in pancreatitis, the depressant effect of FFA could be even

  3. Changes in the serum composition of free-fatty acids during an intravenous glucose tolerance test.

    PubMed

    Soriguer, Federico; García-Serrano, Sara; García-Almeida, Jose M; Garrido-Sánchez, Lourdes; García-Arnés, Juan; Tinahones, Francisco J; Cardona, Isabel; Rivas-Marín, Jose; Gallego-Perales, Jose L; García-Fuentes, Eduardo

    2009-01-01

    Recent studies suggest that measuring the free-fatty acids (FFA) during an intravenous glucose tolerance test (IVGTT) may provide information about the metabolic associations between serum FFA and carbohydrate and insulin metabolism. We evaluated the FFA profile during an IVGTT and determined whether this test changes the composition and concentration of FFA. An IVGTT was given to 38 severely obese persons before and 7 months after undergoing bariatric surgery and also to 12 healthy, nonobese persons. The concentration and composition of the FFA were studied at different times during the test. The concentration of FFA fell significantly faster during the IVGTT in the controls and in the severely obese persons with normal-fasting glucose (NFG) than in the severely obese persons with impaired-fasting glucose (IFG) or type 2 diabetes mellitus (T2DM) (P < 0.05). Significant differences were found in the time to minimum serum concentrations of FFA (control = NFG < IFG < T2DM) (P < 0.001). These variables improved after bariatric surgery in the three groups. The percentage of monounsaturated and n-6 polyunsaturated FFA in the control subjects and in the obese persons, both before and after surgery, decreased significantly during the IVGTT. In conclusion, during an IVGTT, severely obese persons with IFG or T2DM experienced a lower fall in the FFA than the severely obese persons with NFG and the controls, becoming normal after bariatric surgery.

  4. A statistical proxy for sulphuric acid concentration

    NASA Astrophysics Data System (ADS)

    Mikkonen, S.; Romakkaniemi, S.; Smith, J. N.; Korhonen, H.; Petäjä, T.; Plass-Duelmer, C.; Boy, M.; McMurry, P. H.; Lehtinen, K. E. J.; Joutsensaari, J.; Hamed, A.; Mauldin, R. L., III; Birmili, W.; Spindler, G.; Arnold, F.; Kulmala, M.; Laaksonen, A.

    2011-11-01

    Gaseous sulphuric acid is a key precursor for new particle formation in the atmosphere. Previous experimental studies have confirmed a strong correlation between the number concentrations of freshly formed particles and the ambient concentrations of sulphuric acid. This study evaluates a body of experimental gas phase sulphuric acid concentrations, as measured by Chemical Ionization Mass Spectrometry (CIMS) during six intensive measurement campaigns and one long-term observational period. The campaign datasets were measured in Hyytiälä, Finland, in 2003 and 2007, in San Pietro Capofiume, Italy, in 2009, in Melpitz, Germany, in 2008, in Atlanta, Georgia, USA, in 2002, and in Niwot Ridge, Colorado, USA, in 2007. The long term data were obtained in Hohenpeissenberg, Germany, during 1998 to 2000. The measured time series were used to construct proximity measures ("proxies") for sulphuric acid concentration by using statistical analysis methods. The objective of this study is to find a proxy for sulfuric acid that is valid in as many different atmospheric environments as possible. Our most accurate and universal formulation of the sulphuric acid concentration proxy uses global solar radiation, SO2 concentration, condensation sink and relative humidity as predictor variables, yielding a correlation measure (R) of 0.87 between observed concentration and the proxy predictions. Interestingly, the role of the condensation sink in the proxy was only minor, since similarly accurate proxies could be constructed with global solar radiation and SO2 concentration alone. This could be attributed to SO2 being an indicator for anthropogenic pollution, including particulate and gaseous emissions which represent sinks for the OH radical that, in turn, is needed for the formation of sulphuric acid.

  5. A statistical proxy for sulphuric acid concentration

    NASA Astrophysics Data System (ADS)

    Mikkonen, S.; Romakkaniemi, S.; Smith, J. N.; Korhonen, H.; Petäjä, T.; Plass-Duelmer, C.; Boy, M.; McMurry, P. H.; Lehtinen, K. E. J.; Joutsensaari, J.; Hamed, A.; Mauldin, R. L., III; Birmili, W.; Spindler, G.; Arnold, F.; Kulmala, M.; Laaksonen, A.

    2011-07-01

    Gaseous sulphuric acid is a key precursor for new particle formation in the atmosphere. Previous experimental studies have confirmed a strong correlation between the number concentrations of freshly formed particles and the ambient concentrations of sulphuric acid. This study evaluates a body of experimental gas phase sulphuric acid concentrations, as measured by Chemical Ionization Mass Spectrometry (CIMS) during six intensive measurement campaigns and one long-term observational period. The campaign datasets were measured in Hyytiälä, Finland, in 2003 and 2007, in San Pietro Capofiume, Italy, in 2009, in Melpitz, Germany, in 2008, in Atlanta, Georgia, USA, in 2002, and in Niwot Ridge, Colorado, USA, in 2007. The long term data were obtained in Hohenpeissenberg, Germany, during 1998 to 2000. The measured time series were used to construct proximity measures ("proxies") for sulphuric acid concentration by using statistical analysis methods. The objective of this study is to find a proxy for sulfuric acid that is valid in as many different atmospheric environments as possible. Our most accurate and universal formulation of the sulphuric acid concentration proxy uses global solar radiation, SO2 concentration, condensation sink and relative humidity as predictor variables, yielding a correlation measure (R) of 0.87 between observed concentration and the proxy predictions. Interestingly, the role of the condensation sink in the proxy was only minor, since similarly accurate proxies could be constructed with global solar radiation and SO2 concentration alone. This could be attributed to SO2 being an indicator for anthropogenic pollution, including particulate and gaseous emissions which represent sinks for the OH radical that, in turn, is needed for the formation of sulphuric acid.

  6. Hyaluronic acid concentration in liver diseases.

    PubMed

    Gudowska, Monika; Gruszewska, Ewa; Panasiuk, Anatol; Cylwik, Bogdan; Flisiak, Robert; Świderska, Magdalena; Szmitkowski, Maciej; Chrostek, Lech

    2016-11-01

    The aim of this study was to evaluate the effect of liver diseases of different etiologies and clinical severity of liver cirrhosis on the serum level of hyaluronic acid. The results were compared with noninvasive markers of liver fibrosis: APRI, GAPRI, HAPRI, FIB-4 and Forn's index. Serum samples were obtained from 20 healthy volunteers and patients suffering from alcoholic cirrhosis (AC)-57 patients, non-alcoholic cirrhosis (NAC)-30 and toxic hepatitis (HT)-22. Cirrhotic patients were classified according to Child-Pugh score. Hyaluronic acid concentration was measured by the immunochemical method. Non-patented indicators were calculated using special formulas. The mean serum hyaluronic acid concentration was significantly higher in AC, NAC and HT group in comparison with the control group. There were significant differences in the serum hyaluronic acid levels between liver diseases, and in AC they were significantly higher than those in NAC and HT group. The serum hyaluronic acid level differs significantly due to the severity of cirrhosis and was the highest in Child-Pugh class C. The sensitivity, specificity, accuracy, positive and negative predictive values and the area under the ROC curve for hyaluronic acid and all non-patented algorithms were high and similar to each other. We conclude that the concentration of hyaluronic acid changes in liver diseases and is affected by the severity of liver cirrhosis. Serum hyaluronic acid should be considered as a good marker for noninvasive diagnosis of liver damage, but the combination of markers is more useful.

  7. Nonoxidative Free Fatty Acid Disposal Is Greater in Young Women than Men

    PubMed Central

    Koutsari, Christina; Basu, Rita; Rizza, Robert A.; Nair, K. Sreekumaran; Khosla, Sundeep

    2011-01-01

    Context: Large increases in systemic free fatty acid (FFA) availability in the absence of a corresponding increase in fatty acid oxidation can create a host of metabolic abnormalities. These adverse responses are thought to be the result of fatty acids being shunted into hepatic very low-density lipoprotein-triglyceride production and/or intracellular lipid storage and signaling pathways because tissues are forced to increase nonoxidative FFA disposal. Objective: The objective of the study was to examine whether variations in postabsorptive nonoxidative FFA disposal within the usual range predict insulin resistance and hypertriglyceridemia. Design: We measured: systemic FFA turnover using a continuous iv infusion of [9–10, 3H]palmitate; substrate oxidation with indirect calorimetry combined with urinary nitrogen excretion; whole-body and peripheral insulin sensitivity with the labeled iv glucose tolerance test minimal model. Setting: the study was conducted at the Mayo Clinic General Clinical Research Center. Participants: Participants included healthy, postabsorptive, nonobese adults (21 women and 21 men). Interventions: There were no interventions. Main Outcome Measures: Nonoxidative FFA disposal (micromoles per minute), defined as the FFA disappearance rate minus fatty acid oxidation. Results: Women had 64% greater nonoxidative FFA disposal rate than men but a better lipid profile and similar insulin sensitivity. There was no significant correlation between nonoxidative FFA disposal and whole-body sensitivity, peripheral insulin sensitivity, or fasting serum triglyceride concentrations in men or women. Conclusions: Healthy nonobese women have greater rates of nonoxidative FFA disposal than men, but this does not appear to relate to adverse health consequences. Understanding the sex-specific interaction between adipose tissue lipolysis and peripheral FFA removal will help to discover new approaches to treat FFA-induced abnormalities. PMID:21123445

  8. FFA2 Contribution to Gestational Glucose Tolerance Is Not Disrupted by Antibiotics

    PubMed Central

    Li, Xiaoran; Fisch, Robert; Bughara, Moneb; Wicksteed, Barton; Kovatcheva-Datchary, Petia; Layden, Brian T.

    2016-01-01

    During the insulin resistant phase of pregnancy, the mRNA expression of free fatty acid 2 receptor (Ffar2) is upregulated and as we recently reported, this receptor contributes to insulin secretion and pancreatic beta cell mass expansion in order to maintain normal glucose homeostasis during pregnancy. As impaired gestational glucose levels can affect metabolic health of offspring, we aimed to explore the role of maternal Ffar2 expression during pregnancy on the metabolic health of offspring and also the effects of antibiotics, which have been shown to disrupt gut microbiota fermentative activity (the source of the FFA2 ligands) on gestational glucose homeostasis. We found that maternal Ffar2 expression and impaired glucose tolerance during pregnancy had no effect on the growth rates, ad lib glucose and glucose tolerance in the offspring between 3 and 6 weeks of age. To disrupt short chain fatty acid production, we chronically treated WT mice and Ffar2-/- mice with broad range antibiotics and further compared their glucose tolerance prior to pregnancy and at gestational day 15, and also quantified cecum and plasma SCFAs. We found that during pregnancy antibiotic treatment reduced the levels of SCFAs in the cecum of the mice, but resulted in elevated levels of plasma SCFAs and altered concentrations of individual SCFAs. Along with these changes, gestational glucose tolerance in WT mice, but not Ffar2-/- mice improved while on antibiotics. Additional data showed that gestational glucose tolerance worsened in Ffar2-/- mice during a second pregnancy. Together, these results indicate that antibiotic treatment alone is inadequate to deplete plasma SCFA concentrations, and that modulation of gut microbiota by antibiotics does not disrupt the contribution of FFA2 to gestational glucose tolerance. PMID:27959892

  9. Accumulating Evidence Supports a Taste Component for Free Fatty Acids in Humans

    PubMed Central

    Mattes, Richard D.

    2011-01-01

    The requisite criteria for what constitutes a taste primary have not been established. Recent advances in understanding of the mechanisms and functions of taste have prompted suggestions for an expanded list of unique taste sensations, including fat, or more specifically, free fatty acids (FFA). A set of criteria are proposed here and the data related to FFA are reviewed on each point. It is concluded that the data are moderate to strong that there are: A) adaptive advantages to FFA detection in the oral cavity; B) adequate concentrations of FFA to serve as taste stimuli; C) multiple complimentary putative FFA receptors on taste cells; D) signals generated by FFA that are conveyed by gustatory nerves; E) sensations generated by FFA that can be detected and scaled by psychophysical methods in humans when non-gustatory cues are masked; and F) physiological responses to oral fat/FFA exposure. On no point is there strong evidence challenging these observations. The reviewed findings are suggestive, albeit not definitive, that there is a taste component for FFA. PMID:21557960

  10. In vitro analysis of flufenamic acid activity against Candida albicans biofilms.

    PubMed

    Chavez-Dozal, Alba A; Jahng, Maximillian; Rane, Hallie S; Asare, Kingsley; Kulkarny, Vibhati V; Bernardo, Stella M; Lee, Samuel A

    2014-01-01

    In a recent high-throughput screen against specific Candida albicans drug targets, several compounds that exhibited non-specific antifungal activity were identified, including the non-steroidal anti-inflammatory drug flufenamic acid (FFA). This study sought to determine the effect of different doses of FFA, alone or in combination with fixed concentrations of the standard antifungal agents amphotericin B (AmB), caspofungin (CAS) or fluconazole (FLU), for the prevention and treatment of C. albicans biofilms. Biofilms were formed in a 96-well microplate followed by evaluation of antifungal activity using the XTT assay. FFA concentrations of ≥512mg/L demonstrated >80% prevention of biofilm formation. FFA concentrations of 1024mg/L demonstrated >85% reduction of mature biofilms. When FFA (≥8mg/L) was used in combination with FLU (32mg/L), antifungal activity increased to 99% for the prevention of biofilm formation. Similarly, when a FFA concentration of ≥8mg/L was used in combination with either AmB (0.25mg/L) or CAS (0.125mg/L), antifungal activity also increased up to 99% for the prevention of biofilm formation. The inhibitory effect of FFA on C. albicans biofilms has not been reported previously, therefore these findings suggest that FFA in combination with traditional antifungals might be useful for the treatment and prevention of C. albicans biofilms.

  11. FFA4/GPR120 agonists: a survey of the recent patent literature.

    PubMed

    Formicola, Rosa; Pevarello, Paolo; Kuhn, Christina; Liberati, Chiara; Piscitelli, Francesco; Sodano, Mariangela

    2015-01-01

    FFA4/GPR120, a member of the rhodopsin family of G-protein-coupled receptors (GPCRs), is becoming an important target for therapeutic intervention in several areas of disease, including metabolic diseases, inflammation and cancer. In the last few years several patents on original chemotypes have been generated by different companies. In this review an analysis of the patents in the FFA4 agonism field is presented, with an emphasis on the documents published between 2013 and mid-2015. A discussion of the biological methods used in the patents is included. The general interest in this area is growing fast as half of the existing patents on FFA4 agonists have been issued after 2013. There is, however, a need of further diversifying new chemical classes away form the current substrate-like, carboxylic acid-containing agonists.

  12. Modeling of free fatty acid dynamics: insulin and nicotinic acid resistance under acute and chronic treatments.

    PubMed

    Andersson, Robert; Kroon, Tobias; Almquist, Joachim; Jirstrand, Mats; Oakes, Nicholas D; Evans, Neil D; Chappel, Michael J; Gabrielsson, Johan

    2017-02-21

    Nicotinic acid (NiAc) is a potent inhibitor of adipose tissue lipolysis. Acute administration results in a rapid reduction of plasma free fatty acid (FFA) concentrations. Sustained NiAc exposure is associated with tolerance development (drug resistance) and complete adaptation (FFA returning to pretreatment levels). We conducted a meta-analysis on a rich pre-clinical data set of the NiAc-FFA interaction to establish the acute and chronic exposure-response relations from a macro perspective. The data were analyzed using a nonlinear mixed-effects framework. We also developed a new turnover model that describes the adaptation seen in plasma FFA concentrations in lean Sprague-Dawley and obese Zucker rats following acute and chronic NiAc exposure. The adaptive mechanisms within the system were described using integral control systems and dynamic efficacies in the traditional [Formula: see text] model. Insulin was incorporated in parallel with NiAc as the main endogenous co-variate of FFA dynamics. The model captured profound insulin resistance and complete drug resistance in obese rats. The efficacy of NiAc as an inhibitor of FFA release went from 1 to approximately 0 during sustained exposure in obese rats. The potency of NiAc as an inhibitor of insulin and of FFA release was estimated to be 0.338 and 0.436 [Formula: see text], respectively, in obese rats. A range of dosing regimens was analyzed and predictions made for optimizing NiAc delivery to minimize FFA exposure. Given the exposure levels of the experiments, the importance of washout periods in-between NiAc infusions was illustrated. The washout periods should be [Formula: see text]2 h longer than the infusions in order to optimize 24 h lowering of FFA in rats. However, the predicted concentration-response relationships suggests that higher AUC reductions might be attained at lower NiAc exposures.

  13. Associations of free fatty acids with insulin secretion and action among African-American and European-American girls and women.

    PubMed

    Goree, Laura Lee T; Darnell, Betty E; Oster, Robert A; Brown, Marian A; Gower, Barbara A

    2010-02-01

    Ethnic differences in insulin secretion and action between African Americans (AAs) and European Americans (EAs) may influence mobilization of free fatty acids (FFAs). We tested the hypotheses that FFA concentrations would be associated with measures of insulin secretion and action before and during a glucose challenge test. Subjects were 48 prepubertal girls, 60 premenopausal women, and 46 postmenopausal women. Fasting insulin (insulin(0)), the acute insulin response to glucose (AIR(g)), the insulin sensitivity index (S(I)), basal and nadir FFA (FFA(0), FFA(nadir)), and nadir time (TIME(nadir)) were determined during an intravenous glucose tolerance test (IVGTT). Stepwise multiple linear regression (MLR) analysis was conducted to identify associations of FFA(0), FFA(nadir), and TIME(nadir) with ethnicity, age group, insulin measures, indexes of body composition from dual-energy X-ray absorptiometry, and measures of fat distribution from computed tomography scan. In this population, insulin(0) and AIR(g) were higher among AAs vs. EAs, whereas S(I) was lower, independent of age group. MLR analyses indicated that FFA(0) was best predicted by lean tissue mass (LTM), leg fat mass, ethnicity (lower in AAs), S(I), and insulin(0). FFA(nadir) was best predicted by FFA(0), age group, and intra-abdominal adipose tissue (IAAT). TIME(nadir) was best predicted by leg fat mass, AIR(g), and S(I). In conclusion, indexes of insulin secretion and action were associated with FFA dynamics in healthy girls and women. Lower FFA(0) among AAs was independent of insulin(0) and S(I). Whether lower FFA(0) is associated with substrate oxidation or risk for obesity remains to be determined.

  14. Regulation of prohormone convertase 2 protein expression via GPR40/FFA1 in the hypothalamus.

    PubMed

    Nakamoto, Kazuo; Aizawa, Fuka; Nishinaka, Takashi; Tokuyama, Shogo

    2015-09-05

    Previous studies have shown that the administration of docosahexaenoic acid (DHA) or GW9508, a GPR40/FFA1 (free fatty acid receptor) agonist, facilitates β-endorphin release in the arcuate nucleus of the hypothalamus in mice. However, the mechanisms mediating β-endorphin release induced by GPR40/FFA1 agonists remain unknown. In this study, we focused on the changes in expression of hypothalamic prohormone convertase (PC) 2, which is a calcium-dependent subtilisin-related proteolytic enzyme. The intracerebroventricular injection of DHA or GW9508 significantly increased PC2 protein expression in the hypothalamus. This increase in PC2 expression was inhibited by pretreatment with GW1100, a GPR40/FFA1 antagonist. Furthermore, PC2 protein expression gradually increased over time after complete Freund's adjuvant. These increase in PC2 expression were inhibited by pretreatment with GW1100. However, GW1100 by itself had no effect on PC2 levels. Taken together, our findings suggest that activation of the hypothalamic GPR40/FFA1 signaling pathway may regulate β-endorphin release via PC2, and regulate the endogenous pain control system.

  15. Oleic acid exposure of cultured endothelial cells alters lipid mediator production

    EPA Science Inventory

    Diesel, biodiesel, and other combustion sources contain free fatty acid (FFA) components capable of entering the body through particulate inhalation. FFA can also be endogenously released into circulation in response to stress. When in circulation, bioactive FFA may interact with...

  16. State FFA Officers' Confidence and Trustworthiness of Biotechnology Information Sources

    ERIC Educational Resources Information Center

    Wingenbach, Gary J.; Rutherford, Tracy A.

    2007-01-01

    Are state FFA officers' awareness levels of agricultural topics reported in mass media superior to those who do not serve in leadership roles? The purpose of this study was to determine elected state FFA officers' awareness of biotechnology, and their confidence and trust of biotechnology information sources. Descriptive survey methods were used…

  17. Agrarianism: An Ideology of the National FFA Organization

    ERIC Educational Resources Information Center

    Martin, Michael J.; Kitchel, Tracy

    2013-01-01

    The traditions of the National FFA Organization (FFA) are grounded in agrarianism. This ideology focuses on the ability of farming and nature to develop citizens and integrity within people. Agrarianism has been an important thread of American rhetoric since the founding of country. The ideology has morphed over the last two centuries as the…

  18. Factors Influencing or Discouraging Secondary School Students' FFA Participation

    ERIC Educational Resources Information Center

    Phelps, Kirstin; Henry, Anna L.; Bird, William A.

    2012-01-01

    Modern adolescents are faced with a variety of choices regarding how to spend their free time. As recruitment and increased student participation continues to be a major priority of the National FFA Organization, it is essential to explore the reasons why students make the choice to become or not to become a member of FFA. This study was a part of…

  19. The Benefits of FFA Membership as Part of Agricultural Education

    ERIC Educational Resources Information Center

    Rose, Chelsea; Stephens, Carrie A.; Stripling, Christopher; Cross, Tim; Sanok, Danielle E.; Brawner, Shelby

    2016-01-01

    The study sought to identify the benefits of FFA membership based on the fulfillment of three basic human needs: love and belonging, self-esteem, and self-actualization. The study focused on the fulfillment of FFA members' basic human needs as defined by Abraham Maslow. The three needs on which this study focused are: love and belonging,…

  20. An Examination of Middle School Agricultural Education and FFA Programs: Survey Results from State FFA Executive Secretaries.

    ERIC Educational Resources Information Center

    Rossetti, Rosemarie; McCaslin, N. L.

    A study collected information from 52 of the 53 state Future Farmers of America (FFA) executive secretaries who were sent questionnaires on middle school student enrollment in agricultural education and membership in the national FFA organization. Results showed that 30 states have agricultural education programs in the middle school level, with a…

  1. Ferric sulphate catalysed esterification of free fatty acids in waste cooking oil.

    PubMed

    Gan, Suyin; Ng, Hoon Kiat; Ooi, Chun Weng; Motala, Nafisa Osman; Ismail, Mohd Anas Farhan

    2010-10-01

    In this work, the esterification of free fatty acids (FFA) in waste cooking oil catalysed by ferric sulphate was studied as a pre-treatment step for biodiesel production. The effects of reaction time, methanol to oil ratio, catalyst concentration and temperature on the conversion of FFA were investigated on a laboratory scale. The results showed that the conversion of FFA reached equilibrium after an hour, and was positively dependent on the methanol to oil molar ratio and temperature. An optimum catalyst concentration of 2 wt.% gave maximum FFA conversion of 59.2%. For catalyst loadings of 2 wt.% and below, this catalysed esterification was proposed to follow a pseudo-homogeneous pathway akin to mineral acid-catalysed esterification, driven by the H(+) ions produced through the hydrolysis of metal complex [Fe(H(2)O)(6)](3+) (aq).

  2. Micelles Protect and Concentrate Activated Acetic Acid

    NASA Astrophysics Data System (ADS)

    Todd, Zoe; House, C.

    2014-01-01

    As more and more exoplanets are discovered and the habitability of such planets is considered, one can turn to searching for the origin of life on Earth in order to better understand what makes a habitable planet. Activated acetic acid, or methyl thioacetate, has been proposed to be central to the origin of life on Earth, and also as an important energy currency molecule in early cellular evolution. We have investigated the hydrolysis of methyl thioacetate under various conditions. Its uncatalyzed rate of hydrolysis is about three orders of magnitude faster (K = 0.00663 s^-1; 100°C, pH 7.5, concentration = 0.33mM) than published rates for its catalyzed production making it unlikely to accumulate under prebiotic conditions. However, we also observed that methyl thioacetate was protected from hydrolysis when inside its own hydrophobic droplets. We found that methyl thioacetate protection from hydrolysis was also possible in droplets of hexane and in the membranes of nonanoic acid micelles. Thus, the hydrophobic regions of prebiotic micelles and early cell membranes could have offered a refuge for this energetic molecule increasing its lifetime in close proximity to the reactions for which it would be needed. Methyl thioacetate could thus be important for the origin of life on Earth and perhaps for better understanding the potential habitability of other planets.

  3. Meeting record for FFA working meeting of November 15, 1991

    SciTech Connect

    Stejskal, G.F.

    1992-01-03

    This document provides a meeting record of the Federal Facility Agreement (FFA) working meeting to discuss progress on old issues and further required actions regarding environmental impacts of the Savannah River Facility. (FI)

  4. Serum sialic acid and CEA concentrations in human breast cancer.

    PubMed

    Hogan-Ryan, A; Fennelly, J J; Jones, M; Cantwell, B; Duffy, M J

    1980-04-01

    The concentration of bound sialic acid in the sera of 56 normal subjects and 65 subjects with breast cancer was measured, in order to determine (1) whether serum sialic acid concentrations are raised in breast cancer and (2) whether the concentration of sialic acid in serum reflects tumour stage. The amount of sialic acid in serum was compared to serum carcinoembryonic antigen (CEA) values. Urinary hydroxyproline and serum alkaline phosphatase concentrations were used as indicators of bone and liver involvement. Erythrocyte sedimentation rate (ESR) was also measured. Significantly elevated serum sialic acid concentrations were found in breast cancer, and showed correlation with tumour stage. Serum sialic acid values did not correlate with CEA values. The results suggest that measurement of serum sialic acid concentrations may be of adjunctive value in assessing tumour stage.

  5. Free Amino-acid Concentrations in Fetal Fluids

    PubMed Central

    Cockburn, F.; Robins, S. P.; Forfar, J. O.

    1970-01-01

    The pattern of free amino-acid concentrations in maternal venous plasma, fetal umbilical arterial plasma, fetal urine, and amniotic fluid at 15 to 20 weeks' gestation has been determined. Free amino-acid concentrations were greater in fetal plasma than in maternal plasma, amniotic fluid, or fetal urine. The ratios of amino-acid concentrations in fetal umbilical arterial plasma and urine indicate that the fetal kidney can effectively conserve amino-acids, possibly reaching an adult level of competence in this respect. There was little correlation between amino-acid concentrations in the fluids analysed with the exception of that between amniotic fluid and fetal urine. PMID:5472758

  6. An Analysis of FFA Chapter Demographics as Compared to Schools and Communities

    ERIC Educational Resources Information Center

    Lawrence, Shannon; Rayfield, John; Moore, Lori L.; Outley, Corliss

    2013-01-01

    This descriptive study was a special project for the National FFA [Future Farmers of America] Organization to determine the demographic makeup of rural, suburban, urban, and randomly selected at-large FFA chapters from the four national FFA regions. Summary data for this study revealed that gender in selected FFA chapters was 55% male and 45%…

  7. Winning the War: A Historical Analysis of the FFA during World War II

    ERIC Educational Resources Information Center

    Wolf, Kattlyn J.; Connors, James J.

    2009-01-01

    The United States' participation in World War II affected millions of men, women, and children, both at home and around the world. The war effort also affected the Future Farmers of America (FFA). FFA members, agriculture teachers, and national FFA officers all volunteered to serve their country during the war. Local FFA chapters and individual…

  8. Concentration of Sulphuric Acid: Premature Failure of Bamag Pots,

    DTIC Science & Technology

    1983-05-01

    AD-A139 523 CONCENTRATION OF SULPHURIC ACID: PREMATURE FAILURE OF 1/1 BAMAG POTS(U) MATERIALS RESEARCH LABS ASCOT VAL (AUSTRALIA) J J BATTEN ET AL...VICTORIA REPORT MRL-R-885 CONCENTRATION OF SULPHURIC ACID: PREMATURE FAILURE OF BAMAG POTS Jeffrey J. Batten & Peter J. Knuckey , *. ’ 3 : :, U...black . wi " te, m ith nv: IY)V DEPARTMENT OF DEFENCE MATERIALS RESEARCH LABORATORIES REPORT MRL-R-885 CONCENTRATION OF SULPHURIC ACID: PREMATURE

  9. Effects of weight loss via high fat vs. low fat alternate day fasting diets on free fatty acid profiles.

    PubMed

    Varady, Krista A; Dam, Vi T; Klempel, Monica C; Horne, Matthew; Cruz, Rani; Kroeger, Cynthia M; Santosa, Sylvia

    2015-01-05

    Cardiovascular disease risk is associated with excess body weight and elevated plasma free fatty acid (FFA) concentrations. This study examines how an alternate-day fasting (ADF) diet high (HF) or low (LF) in fat affects plasma FFA profiles in the context of weight loss, and changes in body composition and lipid profiles. After a 2-week weight maintenance period, 29 women (BMI 30-39.9 kg/m(2)) 25-65 years old were randomized to an 8-week ADF-HF (45% fat) diet or an ADF-LF (25% fat) diet with 25% energy intake on fast days and ad libitum intake on feed days. Body weight, BMI and waist circumference were assessed weekly and body composition was measured using dual x-ray absorptiometry (DXA). Total and individual FFA and plasma lipid concentrations were measured before and after weight loss. Body weight, BMI, fat mass, total cholesterol, LDL-C and triglyceride concentrations decreased (P < 0.05) in both groups. Total FFA concentrations also decreased (P < 0.001). In the ADF-LF group, decreases were found in several more FFAs than in the ADF-HF group. In the ADF-HF group, FFA concentrations were positively correlated with waist circumference. Depending on the macronutrient composition of a diet, weight loss with an ADF diet decreases FFA concentrations through potentially different mechanisms.

  10. Differential modulation of alpha 3 beta 2 and alpha 3 beta 4 neuronal nicotinic receptors expressed in Xenopus oocytes by flufenamic acid and niflumic acid.

    PubMed

    Zwart, R; Oortgiesen, M; Vijverberg, H P

    1995-03-01

    Effects of flufenamic acid (FFA) and niflumic acid (NFA), which are often used to block Ca(2+)-activated Cl- current, have been investigated in voltage-clamped Xenopus oocytes expressing alpha 3 beta 2 and alpha 3 beta 4 nicotinic ACh receptors (nAChRs). NFA and FFA inhibit alpha 3 beta 2 nAChR-mediated inward currents and potentiate alpha 3 beta 4 nAChR-mediated inward currents in normal, Cl(-)-free and Ca(2+)-free solutions to a similar extent. The concentration-dependence of the inhibition of alpha 3 beta 2 nAChR-mediated ion current yields IC50 values of 90 microM for FFA and of 260 microM for NFA. The potentiation of alpha 3 beta 4 nAChR-mediated ion current by NFA yields an EC50 value of 30 microM, whereas the effect of FFA does not saturate for concentrations of up to 1 mM. At 100 microM, FFA reduces the maximum of the concentration-effect curve of ACh for alpha 3 beta 2 nAChRs, but leaves the EC50 of ACh unaffected. The same concentration of FFA potentiates alpha 3 beta 4 nAChR-mediated ion currents for all ACh concentrations and causes a small shift of the concentration-effect curve of ACh to lower agonist concentrations. The potentiation, like the inhibition, is most likely due to a noncompetitive effect of FFA. Increasing ACh-induced inward current either by raising the agonist concentration from 10 microM to 200 microM or by coapplication of 10 microM ACh and 200 microM FFA causes a similar enhancement of block of the alpha 3 beta 4 nAChR-mediated ion current by Mg2+. This suggests that the effects of FFA and of an increased agonist concentration result in a similar functional modification of the alpha 3 beta 4 nAChR-operated ion channel. It is concluded that alpha 3 beta 4 and alpha 3 beta 2 nAChRs are oppositely modulated by FFA and NFA through a direct beta-subunit-dependent effect.

  11. DICARBOXYLIC ACID CONCENTRATION TRENDS AND SAMPLING ARTIFACTS

    EPA Science Inventory

    Dicarboxylic acids associated with airborne particulate matter were measured during a summer period in Philadelphia that included multiple air pollution episodes. Samples were collected for two ten hour periods each day using a high volume sampler with two quartz fiber filters in...

  12. Relationship between postabsorptive respiratory exchange ratio and plasma free fatty acid concentrations

    PubMed Central

    Jensen, Michael D.; Bajnárek, Jiří; Lee, Sang Yeoup; Nielsen, Soren; Koutsari, Christina

    2009-01-01

    The relationship between overnight postabsorptive (fasting) respiratory exchange ratio (RER) and plasma FFA concentrations was addressed using data from three separate protocols, each of which involved careful control of the antecedent diet. Protocol 1 examined the relationship between fasting RER and the previous daytime RER. In Protocol 2 fasting, RER and plasma palmitate concentrations were measured in 29 women and 31 men (body mass index <30 kg·m−2). Protocol 3 analyzed data from Nielsen et al. (Nielsen, S., Z. K. Guo, J. B. Albu, S. Klein, P. C. O'Brien, M. D. Jensen. 2003. Energy expenditure, sex and endogenous fuel availability in humans. J. Clin. Invest. 111: 981-988.) to understand how fasting RER and palmitate concentrations relate within individuals during four consecutive measurements. The results were as follows: 1) Fasting RER was correlated (r = 0.74, P < 0.001) with the previous day's average RER, and less so with RER variability. 2) Fasting RER was correlated (r = −0.39, P = 0.007) with fasting plasma palmitate concentrations. 3) The pattern of the RER/palmitate relationship was similar within individuals and between individuals; a negative slope was observed significantly more often than a positive slope (χ2 test; P < 0.001). Our findings suggest that, despite a fixed food quotient, the slight departures from energy equilibrium in a controlled General Clinical Research Center environment can effect plasma FFA concentrations. We suggest that including indirect calorimetry as part of FFA metabolism studies may aid in data interpretation. PMID:19383980

  13. Influence of coffee intake on urinary hippuric acid concentration.

    PubMed

    Ogawa, Masanori; Suzuki, Yoshihiro; Endo, Yoko; Kawamoto, Toshihiro; Kayama, Fujio

    2011-01-01

    Intake of foods and drinks containing benzoic acid influences the urinary hippuric acid (HA) concentration, which is used to monitor toluene exposure in Japan. Therefore, it is necessary to control the intake of benzoic acid before urine collection. Recently, some reports have suggested that components of coffee, such as chlorogenic, caffeic, and quinic acids are metabolized to HA. In this study, we evaluated the influence of coffee intake on the urinary HA concentration in toluene-nonexposed workers who had controlled their benzoic acid intake, and investigated which components of coffee influenced the urinary HA concentration. We collected urine from 15 healthy men who did not handle toluene during working hours, after they had consumed coffee, and we measured their urinary HA concentrations; the benzoic acid intake was controlled in these participants during the study period. The levels of chlorogenic, caffeic, and quinic acids in coffee were analyzed by LC-MS/MS. Urinary HA concentration increased significantly with increasing coffee consumption. Spectrophotometric LC-MS/MS analysis of coffee indicated that it contained chlorogenic and quinic acids at relatively high concentrations but did not contain benzoic acid. Our findings suggest that toluene exposure in coffee-consuming workers may be overestimated.

  14. Occupational Aspirations of State FFA Contest and Award Winners.

    ERIC Educational Resources Information Center

    Bowen, Blannie E.; Doerfert, David L.

    1989-01-01

    A study explored the occupational aspirations of 300 (of 503) students with high levels of participation in Future Farmers of America's (FFA) Computers in Agriculture (CIA), Proficiency Award (PA), and Prepared and Extemporaneous Speaking (PES) contests. CIA and PES winners aspired to professional occupations more than PA winners. PES winners…

  15. Identifying Quality Indicators of SAE and FFA: A Delphi Approach

    ERIC Educational Resources Information Center

    Jenkins, Charles Cordell, III; Kitchel, Tracy

    2009-01-01

    The purpose of this study was to determine quality indicators for SAE and FFA according to 36 experts across the United States. This is a part of a larger study looking at all components of the traditional three-circle model. The study utilized the Delphi technique to garner expert opinion about quality indicators in Agricultural Education. For…

  16. Examining Year-Long Leadership Gains in FFA Members by Prior FFA Involvement, Class Year, and Gender

    ERIC Educational Resources Information Center

    Rosch, David; Simonsen, Jon C.; Velez, Jonathan J.

    2015-01-01

    Students (N = 160) in three diverse FFA chapters were surveyed in early fall, midwinter, and late spring in regard to their leadership skills, confidence in leading, and motivation to engage in leadership-oriented behaviors. The results indicated small-to-moderate gains in transformational leadership skill and a marginally significant…

  17. Vaginal concentrations of lactic acid potently inactivate HIV

    PubMed Central

    Aldunate, Muriel; Tyssen, David; Johnson, Adam; Zakir, Tasnim; Sonza, Secondo; Moench, Thomas; Cone, Richard; Tachedjian, Gilda

    2013-01-01

    Objectives When Lactobacillus spp. dominate the vaginal microbiota of women of reproductive age they acidify the vagina to pH <4.0 by producing ∼1% lactic acid in a nearly racemic mixture of d- and l-isomers. We determined the HIV virucidal activity of racemic lactic acid, and its d- and l-isomers, compared with acetic acid and acidity alone (by the addition of HCl). Methods HIV-1 and HIV-2 were transiently treated with acids in the absence or presence of human genital secretions at 37°C for different time intervals, then immediately neutralized and residual infectivity determined in the TZM-bl reporter cell line. Results l-lactic acid at 0.3% (w/w) was 17-fold more potent than d-lactic acid in inactivating HIVBa-L. Complete inactivation of different HIV-1 subtypes and HIV-2 was achieved with ≥0.4% (w/w) l-lactic acid. At a typical vaginal pH of 3.8, l-lactic acid at 1% (w/w) more potently and rapidly inactivated HIVBa-L and HIV-1 transmitter/founder strains compared with 1% (w/w) acetic acid and with acidity alone, all adjusted to pH 3.8. A final concentration of 1% (w/w) l-lactic acid maximally inactivated HIVBa-L in the presence of cervicovaginal secretions and seminal plasma. The anti-HIV activity of l-lactic acid was pH dependent, being abrogated at neutral pH, indicating that its virucidal activity is mediated by protonated lactic acid and not the lactate anion. Conclusions l-lactic acid at physiological concentrations demonstrates potent HIV virucidal activity distinct from acidity alone and greater than acetic acid, suggesting a protective role in the sexual transmission of HIV. PMID:23657804

  18. Factors Related to the Success of New Mexico Vocational Agriculture Teachers as FFA Advisors

    ERIC Educational Resources Information Center

    Vaughn, Paul R.

    1976-01-01

    A study to identify characteristics which are related to the degree of success of an FFA advisor, and to identify competencies in which a teacher's perceived proficiency are related to his success as an FFA advisor. (HD)

  19. Highly accurate boronimeter assay of concentrated boric acid solutions

    SciTech Connect

    Ball, R.M. )

    1992-01-01

    The Random-Walk Boronimeter has successfully been used as an on-line indicator of boric acid concentration in an operating commercial pressurized water reactor. The principle has been adapted for measurement of discrete samples to high accuracy and to concentrations up to 6000 ppm natural boron in light water. Boric acid concentration in an aqueous solution is a necessary measurement in many nuclear power plants, particularly those that use boric acid dissolved in the reactor coolant as a reactivity control system. Other nuclear plants use a high-concentration boric acid solution as a backup shutdown system. Such a shutdown system depends on rapid injection of the solution and frequent surveillance of the fluid to ensure the presence of the neutron absorber. The two methods typically used to measure boric acid are the chemical and the physical methods. The chemical method uses titration to determine the ionic concentration of the BO[sub 3] ions and infers the boron concentration. The physical method uses the attenuation of neutrons by the solution and infers the boron concentration from the neutron absorption properties. This paper describes the Random-Walk Boronimeter configured to measure discrete samples to high accuracy and high concentration.

  20. Heart Rate Response and Lactic Acid Concentration in Squash Players.

    ERIC Educational Resources Information Center

    Beaudin, Paula; And Others

    1978-01-01

    It was concluded that playing squash is an activity that results in heart rate responses of sufficient intensity to elicit aerobic training effects without producing high lactic acid concentration in the blood. (MM)

  1. Stimulatory short-term effects of free fatty acids on glucagon secretion at low to normal glucose concentrations.

    PubMed

    Bollheimer, L Cornelius; Landauer, Heike C; Troll, Stephanie; Schweimer, Joachim; Wrede, Christian E; Schölmerich, Jürgen; Buettner, Roland

    2004-11-01

    While free fatty acids (FFA) are well known as insulin secretagogues, their effects on pancreatic alpha cells have been mostly neglected. In the present study we therefore systematically analyzed the glucagon metabolism of rat pancreatic islets under the influence of FFA. Primary islets were incubated in the presence or absence of 200 micromol/L albumin-complexed palmitate or oleate at 2.8 mmol/L versus 16.7 mmol/L glucose and glucagon secretion was monitored over 8 hours. In addition to these time-course experiments, dose dependency of palmitate-induced effects was tested by a 2-hour incubation with 50 to 300 micromol/L albumin-complexed palmitate at 2.8 mmol/L and 5.6 mmol/L glucose. Apart from glucagon secretion, intracellular immunoreactive glucagon and cellular preproglucagon-mRNA (PPG-mRNA) content were determined from the remaining cell lysates. FFA, especially palmitate, induced a significant and dose-dependent increase of glucagon secretion (in average 2-fold above control) during the first 120 minutes of incubation at low to normal glucose (2.8 and 5.6 mmol/L). There was no significant glucagonotropic effect of FFA at concomitant 16.7 mmol/L glucose. Intracellular glucagon as well as cellular PPG-mRNA content were found to be dose-dependently diminished by palmitate when compared with untreated controls at 5.6 mmol/L glucose. The present analysis therefore points to a new role for FFA as a nutritient secretagogue and a modulator of alpha-cellular glucagon metabolism.

  2. The Impact of Learning Styles on Learning Outcomes at FFA Camp: What Campers Retain over Time

    ERIC Educational Resources Information Center

    Brown, Nicholas R.; Terry, Robert, Jr.; Kelsey, Kathleen D.

    2013-01-01

    Twenty-four states host FFA summer camps to support adolescent maturation along with indoctrination into the culture and values of the FFA. Camps typically include a variety of activities designed to engage members in social activities and non-formal academic content. More than 1500 campers attend the Oklahoma FFA Alumni Leadership Camp annually…

  3. Student Self-Perceptions of Leadership in Two Missouri FFA Chapters: A Collective Case Study

    ERIC Educational Resources Information Center

    Kagay, Rachel Bartholomew; Marx, Adam A.; Simonsen, Jon C.

    2015-01-01

    The focus of this study is the self-perceptions of leadership engagement of FFA members in two FFA chapters in Missouri. This multiple case study used documentation of student self-perceptions, researcher observations, and focus groups. The two cases included 24 high school students comprised of FFA officers and members, who provided their…

  4. Self-Perceived Youth Leadership and Life Skills of Iowa FFA Members.

    ERIC Educational Resources Information Center

    Wingenbach, Gary J.; Kahler, Alan A.

    1997-01-01

    The Youth Leadership and Life Skills Development Scale was completed by 282 of 316 Iowa Future Farmers of America (FFA) members. The strongest relationship appeared between their scores and FFA leadership activities. Other factors affecting life/leadership skills development included after-school jobs, years in FFA, grades, and gender. (SK)

  5. ADAPTING THE FFA TO A CHANGING PROGRAM OF VOCATIONAL AGRICULTURE. RESEARCH SERIES IN AGRICULTURAL EDUCATION.

    ERIC Educational Resources Information Center

    KANTER, EARL F.; BENDER, RALPH E.

    THE PURPOSE OF THIS NATIONAL STUDY WAS TO SUGGEST WAYS OF ADAPTING THE FUTURE FARMERS OF AMERICA (FFA) TO A CHANGING PROGRAM OF VOCATIONAL AGRICULTURE THROUGH IDENTIFYING NEW PURPOSES OF THE FFA AND EVALUATING SELECTED OPERATIONAL GUIDELINES AND NATIONAL AND STATE FFA ACTIVITIES. MEMBERS OF THE UNITED STATES OFFICE OF EDUCATION, HEAD STATE…

  6. Brain dopamine and amino acid concentrations in Lurcher mutant mice.

    PubMed

    Reader, T A; Strazielle, C; Botez, M I; Lalonde, R

    1998-03-15

    Lurcher mutant mice are characterized by massive degeneration of the cerebellum, including Purkinje cells and granule cells, as well as for the loss of neurons from the inferior olive. Concentrations of dopamine and two of its metabolites and of several amino acid neurotransmitters were determined in the cerebellum and in other brain regions of these mutants. By comparison to wild-type mice of the same background strain, glutamate and taurine concentrations were reduced in the Lurcher cerebellum. No decrease was found for aspartate, gamma-aminobutyric acid (GABA), glycine, as well as dopamine and its metabolites. Moreover, no neurochemical alterations occurred in the brain stem, thalamus, or neostriatum of Lurcher mutants. A selective reduction of glutamate concentration was found in the hippocampus, while all amino acids measured were decreased in the entorhinal-piriform areas. These results indicate region-selective reductions of neurotransmitter concentrations in a mouse mutant with a defined cerebellar cortical pathology.

  7. Concentrating phenolic acids from Lonicera japonica by nanofiltration technology

    NASA Astrophysics Data System (ADS)

    Li, Cunyu; Ma, Yun; Li, Hongyang; Peng, Guoping

    2017-03-01

    Response surface analysis methodology was used to optimize the concentrate process of phenolic acids from Lonicera japonica by nanofiltration technique. On the basis of the influences of pressure, temperature and circulating volume, the retention rate of neochlorogenic acid, chlorogenic acid and 4-dicaffeoylquinic acid were selected as index, molecular weight cut-off of nanofiltration membrane, concentration and pH were selected as influencing factors during concentrate process. The experiment mathematical model was arranged according to Box-Behnken central composite experiment design. The optimal concentrate conditions were as following: nanofiltration molecular weight cut-off, 150 Da; solutes concentration, 18.34 µg/mL; pH, 4.26. The predicted value of retention rate was 97.99% under the optimum conditions, and the experimental value was 98.03±0.24%, which was in accordance with the predicted value. These results demonstrate that the combination of Box-Behnken design and response surface analysis can well optimize the concentrate process of Lonicera japonica water-extraction by nanofiltration, and the results provide the basis for nanofiltration concentrate for heat-sensitive traditional Chinese medicine.

  8. Unprecedented concentrations of indigenous amino acids in primitive CR meteorites

    NASA Astrophysics Data System (ADS)

    Ehrenfreund, Pascale; Martins, Zita; Alexander, Conel; Orzechowska, Grazyna; Fogel, Marylin

    CR meteorites are among the most primitive meteorites. We have performed pioneering work determining the compositional characteristics of amino acids in this type of carbonaceous chondrites. We report the first measurements of amino acids in Antarctic CR meteorites, two of which show the highest amino acid concentrations ever found in a chondrite. We have analyzed the amino acid content of the Antarctic CRs EET92042, GRA95229 and GRO95577 using high performance liquid chromatography with UV fluorescence detection (HPLC-FD) and gas chromatography-mass spectrometry (GC-MS). Additionally, compound-specific carbon isotopic measurements for most of the individual amino acids from the EET92042 and GRA95229 meteorites were achieved by gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS). Our data show that EET92042 and GRA95229 are the most amino acid-rich chondrites ever analyzed, with total amino acid concentrations of 180 and 249 parts-per-million (ppm), respectively. GRO95577, however, is depleted in amino acids (<1 ppm). The most abundant amino acids present in the EET92042 and GRA95229 meteorites are the α-amino acids glycine, isovaline, α-aminoisobutyric acid (α-AIB), and alanine, with δ 13 C values ranging from +31.6% to +50.5%. The highly enriched carbon isotope results together with racemic enantiomeric ratios determined for most amino acids indicate that primitive organic matter was preserved in these meteorites. In addition, the relative abundances of α-AIB and β-alanine amongst Antarctic CR meteorites appear to correspond to the degree of aqueous alteration on their respective parent body. Investigating the abundances and isotopic composition of amino acids in primitive chondrites helps to understand the role of meteorites as a source of extraterrestrial prebiotic organic compounds to the early Earth.

  9. [Does coffee drinking influence serum uric acid concentration?].

    PubMed

    Olak-Białoń, Bogusława; Marcisz, Czesław; Jonderko, Gerard; Olak, Zygfryd; Szymszal, Jan; Orzeł, Arkadiusz

    2004-01-01

    The drinking of coffee, a commonly used beverage, was a subject of many studies, mainly regarded to coffee influence on cardiovascular system. However, only one study indicates that coffee drinking in male adults may lead to decrease in serum uric acid level. Hyperuricaemia is a risk factor of many diseases. The aim of this study was to examine the influence of coffee drinking on serum uric acid concentration. 1955 working persons aged from 18 to 65 years were included into research. There were 571 women among them. We determined energy expenditure during professional work, blood pressure, body mass index, and measured serum levels of uric acid, glucose and creatinine. The amount of coffee and ethanol consumption was evaluated on the ground of an interview. It was showed that persons drinking coffee have lower serum uric acid concentration than non-drinkers, especially among women, who drank more coffee then men. Uricaemia was correlated negatively with number of cups of coffee consumed and positively with body mass index, ethanol consumption and diastolic blood pressure. The author conclude that: 1) among women drinking on an average 10 cups of coffee per week appeared a decrease in serum uric acid concentration and a lower risk of development of hyperuricaemia, 2) elevated serum uric acid concentration is accompanied by elevated blood pressure and increased body mass index.

  10. Simultaneous acetic acid separation and monosaccharide concentration by reverse osmosis.

    PubMed

    Zhou, Fanglei; Wang, Cunwen; Wei, Jiang

    2013-03-01

    This study aimed to investigate the feasibility and efficiency of simultaneous acetic acid separation and sugar concentration in model lignocellulosic hydrolyzates by reverse osmosis. The effects of operation parameters such as pH, temperature, pressure and feed concentration on the solute retentions were examined with a synthetic xylose–glucose–acetic acid model solution. Results showed that the monosaccharides were almost completely rejected at above 20 bar, while the acetic acid retention increased with the increase in pH and pressure, and decreased with the temperature increase. The maximum separation factors of acetic acid over xylose and glucose reached as high as 211.5 and 228.4 at pH 2.93 (the initial pH of model lignocellulosic hydrolyzates), 40 °C and 20 bar. Furthermore, the concentration and diafiltration process were employed at optimal operation conditions. Consequently, a high sugar concentration and a beneficially lower acetic acid concentration were simultaneously achieved by reverse osmosis.

  11. Degree of free fatty acid saturation influences chocolate rejection in human assessors.

    PubMed

    Running, Cordelia A; Hayes, John E; Ziegler, Gregory R

    2017-02-01

    In foods, free fatty acids (FFAs) traditionally have been viewed as contributing an odor, yet evidence has accumulated that FFAs also contribute a unique taste ("oleogustus"). However, minimal work has been conducted using actual foods to test the contribution of FFA to taste preferences. Here, we investigate flavor, taste, and aroma contributions of added FFA in chocolate, as some commercial manufacturers already use lipolysis of triglycerides to generate unique profiles. We hypothesized that small added concentrations of FFAs would increase preferences for chocolate, whereas higher added concentrations would decrease preferences. We also hypothesized a saturated fatty acid (stearic C18) would have a lesser effect than a monounsaturated (oleic C18:1), which would have a lesser effect than a polyunsaturated (linoleic C18:2) fatty acid. For each, paired preference tests were conducted for 10 concentrations (0.04% to 2.25%) of added FFAs compared with the control chocolate without added FFAs. Stearic acid was tested for flavor (tasting and nares open), whereas the unsaturated fatty acids were tested for both aroma (orthonasal only and no tasting) and taste (tasting with nares blocked to eliminate retronasal odor). We found no preference for any added FFA chocolate; however, rejection was observed independently for both taste and aroma of unsaturated fatty acids, with linoleic acid reaching rejection at lower concentrations than oleic acid. These data indicate that degree of unsaturation influences rejection of both FFA aroma and taste in chocolate. Thus, alterations of FFA profiles in foods should be approached cautiously to avoid shifting concentrations of unsaturated fatty acids to hedonically unacceptable levels.

  12. Decreased expression of adipose CD36 and FATP1 are associated with increased plasma nonesterified fatty acids during prolonged fasting in northern elephant seal pups (Mirounga angustirostris)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The northern elephant seal undergoes a 2-3 month post-weaning fast during which it depends primarily on the oxidation of fatty acids to meet its energetic demands. The concentration of plasma free fatty acids (FFA) increases and is associated with the development of insulin resistance in late-fasted...

  13. The In vitro Effects of Nano-encapsulated Conjugated Linoleic Acid on Stability of Conjugated Linoleic Acid and Fermentation Profiles in the Rumen.

    PubMed

    Heo, Wan; Kim, Eun Tae; Cho, Sung Do; Kim, Jun Ho; Kwon, Seong Min; Jeong, Ha Yeon; Ki, Kwang Seok; Yoon, Ho Baek; Ahn, Young Dae; Lee, Sung Sill; Kim, Young Jun

    2016-03-01

    This study was aimed to evaluate the stability of conjugated linoleic acids (CLAs) by nano-encapsulation against in vitro ruminal biohydrogenation by microbial enzymatic conversion. CLAs (free fatty acid form of CLA [CLA-FFA], nano-encapsulated CLA-FFA, triglyceride form of CLA [CLA-TG], and nano-encapsulated CLA-TG) were used in the in vitro fermentation experiments. When Butyrivibrio fibrisolvens (B. fibrisolvens) was incubated with CLA-FFAs, the concentrations of cis-9, trans-11 CLA and vaccenic acid (VA) slightly was decreased and increased by nano-encapsulation, respectively. When B. fibrisolvens was incubated with CLA-TG, the concentrations of cis-9, trans-11 CLA and VA decreased, but these were increased when B. fibrisolvens was incubated with nano-encapsulated CLA-TG. The nano-encapsulation was more effective against the in vitro biohydrogenation activity of B.fibrisolvens incubated with CLA-FFA than with CLA-TG. In the in vitro ruminal incubation test, the total gas production and concentration of total volatile fatty acids incubated with nano-encapsulated CLA-FFA and CLA-TG were increased significantly after 24 h incubation (p<0.05). Nano-encapsulated CLA-FFA might, thus, improve the ruminal fermentation characteristics without adverse effects on the incubation process. In addition, nano-encapsulated CLA-FFA increased the population of Fibrobacter succinogenes and decreased the population of B. fibrisolvens population. These results indicate that nano-encapsulation could be applied to enhance CLA levels in ruminants by increasing the stability of CLA without causing adverse effects on ruminal fermentation.

  14. The In vitro Effects of Nano-encapsulated Conjugated Linoleic Acid on Stability of Conjugated Linoleic Acid and Fermentation Profiles in the Rumen

    PubMed Central

    Heo, Wan; Kim, Eun Tae; Cho, Sung Do; Kim, Jun Ho; Kwon, Seong Min; Jeong, Ha Yeon; Ki, Kwang Seok; Yoon, Ho Baek; Ahn, Young Dae; Lee, Sung Sill; Kim, Young Jun

    2016-01-01

    This study was aimed to evaluate the stability of conjugated linoleic acids (CLAs) by nano-encapsulation against in vitro ruminal biohydrogenation by microbial enzymatic conversion. CLAs (free fatty acid form of CLA [CLA-FFA], nano-encapsulated CLA-FFA, triglyceride form of CLA [CLA-TG], and nano-encapsulated CLA-TG) were used in the in vitro fermentation experiments. When Butyrivibrio fibrisolvens (B. fibrisolvens) was incubated with CLA-FFAs, the concentrations of cis-9, trans-11 CLA and vaccenic acid (VA) slightly was decreased and increased by nano-encapsulation, respectively. When B. fibrisolvens was incubated with CLA-TG, the concentrations of cis-9, trans-11 CLA and VA decreased, but these were increased when B. fibrisolvens was incubated with nano-encapsulated CLA-TG. The nano-encapsulation was more effective against the in vitro biohydrogenation activity of B.fibrisolvens incubated with CLA-FFA than with CLA-TG. In the in vitro ruminal incubation test, the total gas production and concentration of total volatile fatty acids incubated with nano-encapsulated CLA-FFA and CLA-TG were increased significantly after 24 h incubation (p<0.05). Nano-encapsulated CLA-FFA might, thus, improve the ruminal fermentation characteristics without adverse effects on the incubation process. In addition, nano-encapsulated CLA-FFA increased the population of Fibrobacter succinogenes and decreased the population of B. fibrisolvens population. These results indicate that nano-encapsulation could be applied to enhance CLA levels in ruminants by increasing the stability of CLA without causing adverse effects on ruminal fermentation. PMID:26950867

  15. Amino acid rejection behaviour as a function of concentration.

    PubMed

    Shirley, Jason; Mandale, Stephen; Williams, Paul M

    2011-05-11

    The solute rejection versus concentration behaviour of five different amino acids has been investigated using a Nitto Denko NTR7450 nanofiltration membrane. The experimental data for amino acid rejection was also compared against a combined steric and charge rejection model. At its isoelectric point, lysine was effectively neutral and its behaviour was well described by the model incorporating a steric function only. For phenylalanine, the combined model was found to fit the data well. In contrast there was poor agreement between the model and rejection data for glutamine, glutamic acid and glycine whose rejection values at first increased with concentration. This result implied that another governing process was in operation. Dimerisation as an explanation for the observed phenomena was also investigated. Size analysis of amino acid molecules as a function of the prevailing concentration using dynamic light scattering was limited but showed no evidence of dimerisation. This data was supported by osmotic pressure measurements which demonstrated no evidence of non-linearity in the relation between osmotic pressure and concentration.

  16. Comparison and validation of 2 analytical methods for the determination of free fatty acids in dairy products by gas chromatography with flame ionization detection.

    PubMed

    Mannion, David T; Furey, Ambrose; Kilcawley, Kieran N

    2016-07-01

    Accurate quantification of free fatty acids (FFA) in dairy products is important for quality control, nutritional, antimicrobial, authenticity, legislative, and flavor purposes. In this study, the performance of 2 widely used gas chromatographic flame ionization detection methods for determination of FFA in dairy products differing in lipid content and degree of lipolysis were evaluated. We used a direct on-column approach where the isolated FFA extract was injected directly and a derivatization approach where the FFA were esterified in the injector to methyl esters using tetramethylammonium hydroxide as a catalyst. A comprehensive validation was undertaken to establish method linearity, limits of detection, limits of quantification, accuracy, and precision. Linear calibrations of 3 to 700mg/L (R(2)>0.999) and 20 to 700mg/L (R(2)>0.997), and limits of detection and limits of quantification of 0.7 and 3mg/L and 5 and 20mg/L were obtained for the direct injection on-column and the derivatization method, respectively. Intraday precision of 1.5 to 7.2% was obtained for both methods. The direct injection on-column method had the lower levels of limits of detection and quantification, because FFA are directly injected onto the GC as opposed to the split injection used in the derivatization method. However, the direct injection on-column method experienced accumulative column phase deterioration and irreversible FFA absorption because of the acidic nature of the injection extract, which adversely affected method robustness and the quantification of some longer chain FFA. The derivatization method experienced issues with quantification of butyric acid at low concentrations because of coelution with the injection solvent peak, loss of polyunsaturated FFA due to degradation by tetramethylammonium hydroxide, and the periodic emergence of by-product peaks of the tetramethylammonium hydroxide reaction that interfered with the quantification of some short-chain FFA. The

  17. Plasma adipokine and inflammatory marker concentrations are altered in obese, as opposed to non-obese, type 2 diabetes patients.

    PubMed

    Hansen, Dominique; Dendale, Paul; Beelen, Milou; Jonkers, Richard A M; Mullens, Annelies; Corluy, Luk; Meeusen, Romain; van Loon, Luc J C

    2010-06-01

    Elevated plasma free fatty acid (FFA), inflammatory marker, and altered adipokine concentrations have been observed in obese type 2 diabetes patients. It remains unclear whether these altered plasma concentrations are related to the diabetic state or presence of obesity. In this cross-sectional observational study, we compare basal plasma FFA, inflammatory marker, and adipokine concentrations between obese and non-obese type 2 diabetes patients and healthy, non-obese controls. A total of 20 healthy, normoglycemic males (BMI <30 kg/m(2)), 20 non-obese (BMI <30 kg/m(2)) and 20 obese (BMI >35 kg/m(2)) type 2 diabetes patients were selected to participate in this study. Groups were matched for age and habitual physical activity level. Body composition, glycemic control, and exercise performance capacity were assessed. Basal blood samples were collected to determine plasma leptin, adiponectin, resistin, tumor necrosis factor alpha (TNFalpha), interleukin-6 (IL-6), high-sensitivity C-reactive protein (hsCRP) and FFA concentrations. Plasma FFA, inflammatory marker (hsCRP, IL-6, TNFalpha), adipokine (adiponectin, resistin, leptin), and triglyceride concentrations did not differ between non-obese diabetes patients and healthy, normoglycemic controls. Plasma FFA, IL-6, hsCRP, leptin, and triglyceride levels were significantly higher in the obese diabetes patients when compared with the healthy normoglycemic controls (P < 0.05). Furthermore, plasma hsCRP and leptin levels were significantly higher in the obese versus non-obese diabetes patients (P < 0.05). Significant correlations between plasma parameters and glycemic control were observed, but disappeared after adjusting for trunk adipose tissue mass. Elevated plasma leptin, hsCRP, IL-6, and FFA concentrations are associated with obesity and not necessarily with the type 2 diabetic state.

  18. Plasma long-chain free fatty acids predict mammalian longevity.

    PubMed

    Jové, Mariona; Naudí, Alba; Aledo, Juan Carlos; Cabré, Rosanna; Ayala, Victoria; Portero-Otin, Manuel; Barja, Gustavo; Pamplona, Reinald

    2013-11-28

    Membrane lipid composition is an important correlate of the rate of aging of animals and, therefore, the determination of their longevity. In the present work, the use of high-throughput technologies allowed us to determine the plasma lipidomic profile of 11 mammalian species ranging in maximum longevity from 3.5 to 120 years. The non-targeted approach revealed a specie-specific lipidomic profile that accurately predicts the animal longevity. The regression analysis between lipid species and longevity demonstrated that the longer the longevity of a species, the lower is its plasma long-chain free fatty acid (LC-FFA) concentrations, peroxidizability index, and lipid peroxidation-derived products content. The inverse association between longevity and LC-FFA persisted after correction for body mass and phylogenetic interdependence. These results indicate that the lipidomic signature is an optimized feature associated with animal longevity, emerging LC-FFA as a potential biomarker of longevity.

  19. Xanthan from sulphuric acid treated tapioca pulp: influence of acid concentration on xanthan fermentation.

    PubMed

    Gunasekar, V; Reshma, K R; Treesa, Greeshma; Gowdhaman, D; Ponnusami, V

    2014-02-15

    Xanthan gum was produced by fermentation of sulphuric acid pre-treated tapioca pulp. Effect of sulphuric acid concentration (0.5%, 2.5% and 5.0%) on xanthan fermentation was investigated. Maximum xanthan yield (7.1g/l) was obtained with 0.5% sulphuric acid pre-treatment. Further, increase in sulphuric acid concentration caused formation of inhibitory substance and lowered xanthan yield. The product was confirmed as xanthan using FTIR, (1)H NMR analyses. Viscosity was measured by Brookfield viscometer and the molecular weight was determined from the intrinsic viscosity. The results confirmed that the yield and quality of xanthan produced were strongly influenced by the acid concentration.

  20. The Quest for the FFA and Where It Led.

    PubMed

    Kanwisher, Nancy

    2017-02-01

    This article tells the story behind our first paper on the fusiform face area (FFA): how we chose the question, developed the methods, and followed the data to find the FFA and subsequently many other functionally specialized cortical regions. The paper's impact had less to do with the particular findings in the paper itself and more to do with the method that it promoted and the picture of the human mind and brain that it led to. The use of a functional localizer to define a candidate region in each subject individually enabled us not just to make pictures of brain activation, but also to ask principled, hypothesis-driven questions about a thing in nature. This method enabled stronger and more extensive tests of the function of each cortical region than had been possible before in humans and, as a result, has produced a large body of evidence that the human cortex contains numerous regions that are specifically engaged in particular mental processes. The growing inventory of cortical regions with distinctive and often very specific functions can be seen as an initial sketch of the basic components of the human mind. This sketch also serves as a roadmap into the vast and exciting new landscape of questions about the computations, structural connections, time course, development, plasticity, and evolution of each of these regions, as well as the hardest question of all: how do these regions work together to produce human intelligence?

  1. Delphinidin Reduces Glucose Uptake in Mice Jejunal Tissue and Human Intestinal Cells Lines through FFA1/GPR40.

    PubMed

    Hidalgo, Jorge; Teuber, Stefanie; Morera, Francisco J; Ojeda, Camila; Flores, Carlos A; Hidalgo, María A; Núñez, Lucía; Villalobos, Carlos; Burgos, Rafael A

    2017-04-05

    Anthocyanins are pigments with antihyperglycemic properties, and they are potential candidates for developing functional foods for the therapy or prevention of Diabetes mellitus type 2 (DM2). The mechanism of these beneficial effects of anthocyanins are, however, hard to explain, given their very low bioavailability due to poor intestinal absorption. We propose that free fatty acid receptor 1 (FFA1, also named GPR40), is involved in an inhibitory effect of the anthocyanidin delphinidin over intestinal glucose absorption. We show the direct effects of delphinidin on the intestine using jejunum samples from RF/J mice, and the human intestinal cell lines HT-29, Caco-2, and NCM460. By the use of specific pharmacological antagonists, we determined that delphinidin inhibits glucose absorption in both mouse jejunum and a human enterocytic cell line in a FFA1-dependent manner. Delphinidin also affects the function of sodium-glucose cotransporter 1 (SGLT1). Intracellular signaling after FFA1 activation involved cAMP increase and cytosolic Ca(2+) oscillations originated from intracellular Ca(2+) stores and were followed by store-operated Ca(2+) entry. Taken together, our results suggest a new GPR-40 mediated local mechanism of action for delphinidin over intestinal cells that may in part explain its antidiabetic effect. These findings are promising for the search for new prevention and pharmacological treatment strategies for DM2 management.

  2. Purification and identification of bovine cheese whey fatty acids exhibiting in vitro antifungal activity.

    PubMed

    Clément, M; Tremblay, J; Lange, M; Thibodeau, J; Belhumeur, P

    2008-07-01

    Milk lipids contain several bioactive factors exhibiting antimicrobial activity against bacteria, viruses, and fungi. In the present study, we demonstrate that free fatty acids (FFA) derived from the saponification of bovine whey cream lipids are active in vitro at inhibiting the germination of Candida albicans, a morphological transition associated with pathogenicity. This activity was found to be significantly increased when bovine FFA were enriched in non-straight-chain FFA. At low cell density, this non-straight-chain FFA-enriched fraction was also found to inhibit in a dose-dependant manner the growth of both developmental forms of C. albicans as well as the growth of Aspergillus fumigatus. Using an assay-guided fractionation, the main components responsible for these activities were isolated. On the basis of mass spectroscopic and gas chromatographic analysis, antifungal compounds were identified as capric acid (C10:0), lauroleic acid (C12:1), 11-methyldodecanoic acid (iso-C13:0), myristoleic acid (C14:1n-5), and gamma-linolenic acid (C18:3n-6). The most potent compound was gamma-linolenic acid, with minimal inhibitory concentration values of 5.4 mg/L for C. albicans and 1.3 mg/L for A. fumigatus, in standardized conditions. The results of this study indicate that bovine whey contains bioactive fatty acids exhibiting antifungal activity in vitro against 2 important human fungal pathogens.

  3. FFA-induced hepatic insulin resistance in vivo is mediated by PKCδ, NADPH oxidase, and oxidative stress.

    PubMed

    Pereira, Sandra; Park, Edward; Mori, Yusaku; Haber, C Andrew; Han, Ping; Uchida, Toyoyoshi; Stavar, Laura; Oprescu, Andrei I; Koulajian, Khajag; Ivovic, Alexander; Yu, Zhiwen; Li, Deling; Bowman, Thomas A; Dewald, Jay; El-Benna, Jamel; Brindley, David N; Gutierrez-Juarez, Roger; Lam, Tony K T; Najjar, Sonia M; McKay, Robert A; Bhanot, Sanjay; Fantus, I George; Giacca, Adria

    2014-07-01

    Fat-induced hepatic insulin resistance plays a key role in the pathogenesis of type 2 diabetes in obese individuals. Although PKC and inflammatory pathways have been implicated in fat-induced hepatic insulin resistance, the sequence of events leading to impaired insulin signaling is unknown. We used Wistar rats to investigate whether PKCδ and oxidative stress play causal roles in this process and whether this occurs via IKKβ- and JNK-dependent pathways. Rats received a 7-h infusion of Intralipid plus heparin (IH) to elevate circulating free fatty acids (FFA). During the last 2 h of the infusion, a hyperinsulinemic-euglycemic clamp with tracer was performed to assess hepatic and peripheral insulin sensitivity. An antioxidant, N-acetyl-L-cysteine (NAC), prevented IH-induced hepatic insulin resistance in parallel with prevention of decreased IκBα content, increased JNK phosphorylation (markers of IKKβ and JNK activation, respectively), increased serine phosphorylation of IRS-1 and IRS-2, and impaired insulin signaling in the liver without affecting IH-induced hepatic PKCδ activation. Furthermore, an antisense oligonucleotide against PKCδ prevented IH-induced phosphorylation of p47(phox) (marker of NADPH oxidase activation) and hepatic insulin resistance. Apocynin, an NADPH oxidase inhibitor, prevented IH-induced hepatic and peripheral insulin resistance similarly to NAC. These results demonstrate that PKCδ, NADPH oxidase, and oxidative stress play a causal role in FFA-induced hepatic insulin resistance in vivo and suggest that the pathway of FFA-induced hepatic insulin resistance is FFA → PKCδ → NADPH oxidase and oxidative stress → IKKβ/JNK → impaired hepatic insulin signaling.

  4. The Neutrophil Response Induced by an Agonist for Free Fatty Acid Receptor 2 (GPR43) Is Primed by Tumor Necrosis Factor Alpha and by Receptor Uncoupling from the Cytoskeleton but Attenuated by Tissue Recruitment

    PubMed Central

    Björkman, Lena; Mårtensson, Jonas; Winther, Malene; Gabl, Michael; Holdfeldt, André; Uhrbom, Martin; Bylund, Johan; Højgaard Hansen, Anders; Pandey, Sunil K.; Ulven, Trond; Forsman, Huamei

    2016-01-01

    Ligands with improved potency and selectivity for free fatty acid receptor 2 (FFA2R) have become available, and we here characterize the neutrophil responses induced by one such agonist (Cmp1) and one antagonist (CATPB). Cmp1 triggered an increase in the cytosolic concentration of Ca2+, and the neutrophils were then desensitized to Cmp1 and to acetate, a naturally occurring FFA2R agonist. The antagonist CATPB selectively inhibited responses induced by Cmp1 or acetate. The activated FFA2R induced superoxide anion secretion at a low level in naive blood neutrophils. This response was largely increased by tumor necrosis factor alpha (TNF-α) in a process associated with a recruitment of easily mobilizable granules, but neutrophils recruited to an aseptic inflammation in vivo were nonresponding. Superoxide production induced by Cmp1 was increased in latrunculin A-treated neutrophils, but no reactivation of desensitized FFA2R was induced by this drug, suggesting that the cytoskeleton is not directly involved in terminating the response. The functional and regulatory differences between the receptors that recognize short-chain fatty acids and formylated peptides, respectively, imply different roles of these receptors in the orchestration of inflammation and confirm the usefulness of a selective FFA2R agonist and antagonist as tools for the exploration of the precise role of the FFA2R. PMID:27503855

  5. Adiponectin and visfatin concentrations in children treated with valproic acid.

    PubMed

    Rauchenzauner, Markus; Haberlandt, Edda; Scholl-Bürgi, Sabine; Ernst, Barbara; Hoppichler, Fritz; Karall, Daniela; Ebenbichler, Christoph F; Rostasy, Kevin; Luef, Gerhard

    2008-02-01

    Chronic antiepileptic therapy with valproic acid (VPA) is associated with increased body weight and insulin resistance in adults and children. Attempts to determine the underlying pathophysiologic mechanisms have failed. Adipocytokines have recently been defined as a link between glucose and fat metabolism. We herein demonstrate that VPA-associated overweight is accompanied by lower adiponectin and higher leptin concentrations in children. The absence of any relationship with visfatin concentration does not suggest a role of this novel insulin-mimetic hormone in VPA-associated metabolic alterations. Therefore, adiponectin and leptin but not visfatin may be considered as potential regulators of glucose and fat metabolism during VPA-therapy.

  6. Equilibrium concentrations for pyruvate dehydrogenase and the citric acid cycle at specified concentrations of certain coenzymes.

    PubMed

    Alberty, Robert A

    2004-04-01

    It is of interest to calculate equilibrium compositions of systems of biochemical reactions at specified concentrations of coenzymes because these reactants tend to be in steady states. Thermodynamic calculations under these conditions require the definition of a further transformed Gibbs energy G" by use of a Legendre transform. These calculations are applied to the pyruvate dehydrogenase reaction plus the citric acid cycle, but steady-state concentrations of CoA, acetyl-CoA and succinyl-CoA cannot be specified because they are involved in the conservation of carbon atoms. These calculations require the use of linear algebra to obtain further transformed Gibbs energies of formation of reactants and computer programs to calculate equilibrium compositions. At specified temperature, pH, ionic strength and specified concentrations of several coenzymes, the equilibrium composition depends on the specified concentrations of the coenzymes and the initial amounts of reactants.

  7. The saturated fatty acid, palmitic acid, induces anxiety-like behavior in mice

    PubMed Central

    Moon, Morgan L.; Joesting, Jennifer J.; Lawson, Marcus A.; Chiu, Gabriel S.; Blevins, Neil A.; Kwakwa, Kristin A.; Freund, Gregory G.

    2014-01-01

    Objectives Excess fat in the diet can impact neuropsychiatric functions by negatively affecting cognition, mood and anxiety. We sought to show that the free fatty acid (FFA), palmitic acid, can cause adverse biobehaviors in mice that lasts beyond an acute elevation in plasma FFAs. Methods Mice were administered palmitic acid or vehicle as a single intraperitoneal (IP) injection. Biobehaviors were profiled 2 and 24 hrs after palmitic acid treatment. Quantification of dopamine (DA), norepinephrine (NE), serotonin (5-HT) and their major metabolites was performed in cortex, hippocampus and amygdala. FFA concentration was determined in plasma. Relative fold change in mRNA expression of unfolded protein response (UPR)-associated genes was determined in brain regions. Results In a dose-dependent fashion, palmitic acid rapidly reduced mouse locomotor activity by a mechanism that did not rely on TLR4, MyD88, IL-1, IL-6 or TNFα but was dependent on fatty acid chain length. Twenty-four hrs after palmitic acid administration mice exhibited anxiety-like behavior without impairment in locomotion, food intake, depressive-like behavior or spatial memory. Additionally, the serotonin metabolite 5-HIAA was increased by 33% in the amygdala 24 hrs after palmitic acid treatment. Conclusions Palmitic acid induces anxiety-like behavior in mice while increasing amygdala-based serotonin metabolism. These effects occur at a time point when plasma FFA levels are no longer elevated. PMID:25016520

  8. A Status Report on Middle Grade Agricultural Education and FFA Programs in the United States.

    ERIC Educational Resources Information Center

    Rossetti, Rosemarie; McCaslin, N. L.

    1994-01-01

    Census of 52 Future Farmers of America (FFA) executive secretaries found the following: 30 states have middle-grade agricultural education; 19 have middle-grade FFA membership; 14 have a core agriculture curriculum; 17 have state-level competitions; most do not favor national middle-grade competitions; and few disadvantages apart from potential…

  9. Bridging Horizons. An Advisor's Guide to FFA Involvement for Members with Disabilities.

    ERIC Educational Resources Information Center

    Ploss, Adrienne J.; Field, William E.; Frick, Martin J.

    This guide is designed to provide Future Farmers of America (FFA) advisors with information to assist them in their efforts to include all youth in FFA, including those with disabilities. It addresses benefits of involving youth with disabilities and federal, state, and local legislation and regulations concerning people with disabilities.…

  10. Fitting Vo-Ag and FFA Together Best for Students and Teachers.

    ERIC Educational Resources Information Center

    Snyder, H. Leon

    1979-01-01

    The Future Farmers of America (FFA) is more than a leadership development organization and when used as an intracurricular activity, it can serve as a teaching tool. The FFA adds advantages to the program in areas such as supervised experience, award motivation, providing real world experience, public relations, travel, and competition. (LRA)

  11. Barriers to Participation in the National FFA Organization According to Urban Agriculture Students

    ERIC Educational Resources Information Center

    Martin, Michael J.; Kitchel, Tracy

    2014-01-01

    Urban youth engaged in after-school organizations have more positive attributes compared to their unengaged contemporaries. The FFA is one particular intra-curricular organization with after-school components; yet, urban students do not participate in FFA at the same levels as rural students. The purpose of this descriptive study was to explore…

  12. CO(2)-concentrating: consequences in crassulacean acid metabolism.

    PubMed

    Lüttge, Ulrich

    2002-11-01

    The consequences of CO(2)-concentrating in leaf air-spaces of CAM plants during daytime organic acid decarboxylation in Phase III of CAM (crassulacean acid metabolism) are explored. There are mechanistic consequences of internal CO(2) partial pressures, p(i)(CO(2)). These are (i) effects on stomata, i.e. high p(i)(CO(2)) eliciting stomatal closure in Phase III, (ii) regulation of malic acid remobilization from the vacuole, malate decarboxylation and refixation of CO(2) via Rubisco (ribulose bisphosphate carboxylase/oxygenase), and (iii) internal signalling functions during the transitions between Phases II and III and III and IV, respectively, in the natural day/night cycle and in synchronizing the circadian clocks of individual leaf cells or leaf patches in the free-running endogenous rhythmicity of CAM. There are ecophysiological consequences. Obvious beneficial ecophysiological consequences are (i) CO(2)-acquisition, (ii) increased water-use- efficiency, (iii) suppressed photorespiration, and (iv) reduced oxidative stress by over-energization of the photosynthetic apparatus. However, the general potency of these beneficial effects may be questioned. There are also adverse ecophysiological consequences. These are (i) energetics, (ii) pH effects and (iii) Phase III oxidative stress. A major consequence of CO(2)-concentrating in Phase III is O(2)-concentrating, increased p(i)(CO(2)) is accompanied by increased p(i)(O(2)). Do reversible shifts of C(3)/CAM-intermediate plants between the C(3)-CAM-C(3) modes of photosynthesis indicate that C(3)-photosynthesis provides better protection from irradiance stress? There are many open questions and CAM remains a curiosity.

  13. Association of free fatty acids with the insulin-resistant state but not with central obesity in individuals from Venezuela.

    PubMed

    Campos, Gilberto; Fernández, Virginia; Fernández, Erika; Molero, Emperatriz; Morales, Luz Marina; Raleigh, Xiomara; Connell, Lissette; Ryder, Elena

    2010-03-01

    Individuals with insulin resistance (IR) usually have upper body obesity phenotype, often accompanied by an increase in plasma free fatty acids (FFA). Since the Venezuelan population has a high frequency of IR and central obesity, the purpose of this work was to determine FFA levels in 47 Venezuelan individuals, men and women, 24-58 years old, and analyze their relationship with central obesity and parameters of carbohydrate and lipid metabolism. Basal concentrations of TG, total cholesterol, LDL-C, and HDL-C were measured, and FFA, glucose and insulin, at basal state and at different times after a glucose load. Eighteen individuals presented insulin resistance (HOMA-IR > 2.7) and 29 were non-insulin resistant (non-IR). Insulin resistant individuals (IR) had higher waist circumference, BMI and basal concentrations of FFA than the non-IR. No differences were observed in skin folds and other basal lipids studied. The increased FFA seemed to be related to the IR associated to BMI and not to central obesity, since the difference between IR and non-IR disappeared when they were matched for waist circumference. After a glucose load, FFA decreased in both groups, but remained significantly elevated in IR subjects. This effect disappeared after matching for BMI or waist circumference, inferring that it was independent of anthropometries. FFA were positively associated with HOMA-IR, glucose and TG levels; however, there was.no association with BMI or waist circumference. These findings, and the lack of elements to support the presence of hepatic IR, common to increased visceral lipolysis, might suggest that the IR present in the obese individuals studied, might be due to an increase in subcutaneous fat.

  14. Epilepsy and the concentrations of plasma amino acids in humans.

    PubMed

    Huxtable, R J; Laird, H; Lippincott, S E; Walson, P

    1983-01-01

    We have examined the correlation between the presence of epilepsy in humans, and plasma amino acid levels. Subjects were divided into those having pure generalized tonic-clonic seizures (grand mal group), those having generalized tonic-clonic seizures plus other types of epilepsy (mixed group), and those suffering from epilepsies other than grand mal (no grand mal group). Compared to non-epileptic controls, the grand mal group had significantly higher fasting plasma levels of aspartate (100% increase) and glutamate (380% increase) but significant decreases were seen with phenylalanine (?23%), lysine (?27%), and tryptophan (?30%). The no grand mal group showed similar changes except for lysine. The mixed group showed elevations in glutamate, but decreases only in cysteine and methionine. In response to a high protein meal, plasma levels of alanine, cysteine and methionine rose significantly less for the no grand mal group compared to the control group. Increases in aspartate and glutamate concentrations strongly correlated with the prescription of phenytoin. However, the concentrations of these amino acids were not significantly correlated with the actual plasma levels of phenytoin.

  15. Chronic Reduction of Plasma Free Fatty Acid Improves Mitochondrial Function and Whole-Body Insulin Sensitivity in Obese and Type 2 Diabetic Individuals

    PubMed Central

    Daniele, Giuseppe; Eldor, Roy; Merovci, Aurora; Clarke, Geoffrey D.; Xiong, Juan; Tripathy, Devjit; Taranova, Anna; Abdul-Ghani, Muhammad

    2014-01-01

    Insulin resistance and dysregulation of free fatty acid (FFA) metabolism are core defects in type 2 diabetic (T2DM) and obese normal glucose tolerant (NGT) individuals. Impaired muscle mitochondrial function (reduced ATP synthesis) also has been described in insulin-resistant T2DM and obese subjects. We examined whether reduction in plasma FFA concentration with acipimox improved ATP synthesis rate and altered reactive oxygen species (ROS) production. Eleven NGT obese and 11 T2DM subjects received 1) OGTT, 2) euglycemic insulin clamp with muscle biopsy, and 3) 1H-magnetic resonance spectroscopy of tibialis anterior muscle before and after acipimox (250 mg every 6 h for 12 days). ATP synthesis rate and ROS generation were measured in mitochondria isolated from muscle tissue ex vivo with chemoluminescence and fluorescence techniques, respectively. Acipimox 1) markedly reduced the fasting plasma FFA concentration and enhanced suppression of plasma FFA during oral glucose tolerance tests and insulin clamp in obese NGT and T2DM subjects and 2) enhanced insulin-mediated muscle glucose disposal and suppression of hepatic glucose production. The improvement in insulin sensitivity was closely correlated with the decrease in plasma FFA in obese NGT (r = 0.81) and T2DM (r = 0.76) subjects (both P < 0.001). Mitochondrial ATP synthesis rate increased by >50% in both obese NGT and T2DM subjects and was strongly correlated with the decrease in plasma FFA and increase in insulin-mediated glucose disposal (both r > 0.70, P < 0.001). Production of ROS did not change after acipimox. Reduction in plasma FFA in obese NGT and T2DM individuals improves mitochondrial ATP synthesis rate, indicating that the mitochondrial defect in insulin-resistant individuals is, at least in part, reversible. PMID:24353180

  16. Chronic reduction of plasma free fatty acid improves mitochondrial function and whole-body insulin sensitivity in obese and type 2 diabetic individuals.

    PubMed

    Daniele, Giuseppe; Eldor, Roy; Merovci, Aurora; Clarke, Geoffrey D; Xiong, Juan; Tripathy, Devjit; Taranova, Anna; Abdul-Ghani, Muhammad; DeFronzo, Ralph A

    2014-08-01

    Insulin resistance and dysregulation of free fatty acid (FFA) metabolism are core defects in type 2 diabetic (T2DM) and obese normal glucose tolerant (NGT) individuals. Impaired muscle mitochondrial function (reduced ATP synthesis) also has been described in insulin-resistant T2DM and obese subjects. We examined whether reduction in plasma FFA concentration with acipimox improved ATP synthesis rate and altered reactive oxygen species (ROS) production. Eleven NGT obese and 11 T2DM subjects received 1) OGTT, 2) euglycemic insulin clamp with muscle biopsy, and 3) (1)H-magnetic resonance spectroscopy of tibialis anterior muscle before and after acipimox (250 mg every 6 h for 12 days). ATP synthesis rate and ROS generation were measured in mitochondria isolated from muscle tissue ex vivo with chemoluminescence and fluorescence techniques, respectively. Acipimox 1) markedly reduced the fasting plasma FFA concentration and enhanced suppression of plasma FFA during oral glucose tolerance tests and insulin clamp in obese NGT and T2DM subjects and 2) enhanced insulin-mediated muscle glucose disposal and suppression of hepatic glucose production. The improvement in insulin sensitivity was closely correlated with the decrease in plasma FFA in obese NGT (r = 0.81) and T2DM (r = 0.76) subjects (both P < 0.001). Mitochondrial ATP synthesis rate increased by >50% in both obese NGT and T2DM subjects and was strongly correlated with the decrease in plasma FFA and increase in insulin-mediated glucose disposal (both r > 0.70, P < 0.001). Production of ROS did not change after acipimox. Reduction in plasma FFA in obese NGT and T2DM individuals improves mitochondrial ATP synthesis rate, indicating that the mitochondrial defect in insulin-resistant individuals is, at least in part, reversible.

  17. Mechanochemical leaching of chalcopyrite concentrate by sulfuric acid

    NASA Astrophysics Data System (ADS)

    Mohammadabad, Farhad Khorramshahi; Hejazi, Sina; khaki, Jalil Vahdati; Babakhani, Abolfazl

    2016-04-01

    This study aimed to introduce a new cost-effective methodology for increasing the leaching efficiency of chalcopyrite concentrates at ambient temperature and pressure. Mechanical activation was employed during the leaching (mechanochemical leaching) of chalcopyrite concentrates in a sulfuric acid medium at room temperature and atmospheric pressure. High energy ball milling process was used during the leaching to provide the mechanochemical leaching condition, and atomic absorption spectroscopy and cyclic voltammetry were used to determine the leaching behavior of chalcopyrite. Moreover, X-ray diffraction and scanning electron microscopy were used to characterize the chalcopyrite powder before and after leaching. The results demonstrated that mechanochemical leaching was effective; the extraction of copper increased significantly and continuously. Although the leaching efficiency of chalcopyrite was very low at ambient temperature, the percentages of copper dissolved in the presence of hydrogen peroxide (H2O2) and ferric sulfate (Fe2(SO4)3) after 20 h of mechanochemical leaching reached 28% and 33%, respectively. Given the efficiency of the developed method and the facts that it does not require the use of an autoclave and can be conducted at room temperature and atmospheric pressure, it represents an economical and easy-to-use method for the leaching industry.

  18. A study of the relationship between bile salts, bile salt-stimulated lipase, and free fatty acids in breast milk: normal infants and those with breast milk jaundice.

    PubMed

    Forsyth, J S; Donnet, L; Ross, P E

    1990-08-01

    Breast milk jaundice has been reported to be associated with increased lipase activity and elevated free fatty acid (FFA) concentrations within breast milk. We have previously shown that bile salts are present in small concentrations in breast milk and the aim of this study was to examine the relationship of bile salt-stimulated lipase (BSSL) activity, FFA concentration, and bile salt concentration in milks of normal infants and the milk of infants with breast milk jaundice. Mothers of healthy newborn infants were recruited in the early newborn period and 42 provided breast milk samples at 2 weeks, 30 at 6 weeks, 16 at 10 weeks, and 13 at 14 weeks postnatally. We initially studied the effect of lactation on bile salts and found there was a significant decline in both cholate and chenodeoxycholate levels with duration of lactation (p less than 0.05). There was also a significant fall in BSSL activity with duration of lactation (p less than 0.05), but no correlation was found between BSSL activity and bile salt concentration. FFA concentrations were similar throughout lactation and were not related to either BSSL activity or bile salt concentration. There was a significant increase in the concentration of cholate and the cholate-to-chenodeoxycholate ratio in the milks of 12 infants with breast milk jaundice compared with normal milks, the BSSL activity was similar and contrary to previous reports, the FFA concentration was not increased in the milks of infants with breast milk jaundice.

  19. Chromotropic acid-formaldehyde reaction in strongly acidic media. The role of dissolved oxygen and replacement of concentrated sulphuric acid.

    PubMed

    Fagnani, E; Melios, C B; Pezza, L; Pezza, H R

    2003-05-28

    The procedure for formaldehyde analysis recommended by the National Institute for Occupational Safety and Health (NIOSH) is the Chromotropic acid spectrophotometric method, which is the one that uses concentrated sulphuric acid. In the present study the oxidation step associated with the aforementioned method for formaldehyde determination was investigated. Experimental evidence has been obtained indicating that when concentrated H(2)SO(4) (18 mol l(-1)) is used (as in the NIOSH procedure) that acid is the oxidizing agent. On the other hand, oxidation through dissolved oxygen takes place when concentrated H(2)SO(4) is replaced by concentrated hydrochloric (12 mol l(-1)) and phosphoric (14.7 mol l(-1)) acids as well as by diluted H(2)SO(4) (9.4 mol l(-1)). Based on investigations concerning the oxidation step, a modified procedure was devised, in which the use of the potentially hazardous and corrosive concentrated H(2)SO(4) was eliminated and advantageously replaced by a less harmful mixture of HCl and H(2)O(2).

  20. Sex Steroid Modulation of Fatty Acid Utilization and Fatty Acid Binding Protein Concentration in Rat Liver

    PubMed Central

    Ockner, Robert K.; Lysenko, Nina; Manning, Joan A.; Monroe, Scott E.; Burnett, David A.

    1980-01-01

    The mechanism by which sex steroids influence very low density hepatic lipoprotein triglyceride production has not been fully elucidated. In previous studies we showed that [14C]oleate utilization and incorporation into triglycerides were greater in hepatocyte suspensions from adult female rats than from males. The sex differences were not related to activities of the enzymes of triglyceride biosynthesis, whereas fatty acid binding protein (FABP) concentration in liver cytosol was greater in females. These findings suggested that sex differences in lipoprotein could reflect a sex steroid influence on the availability of fatty acids for hepatocellular triglyceride biosynthesis. In the present studies, sex steroid effects on hepatocyte [14C]oleate utilization and FABP concentration were investigated directly. Hepatocytes from immature (30-d-old) rats exhibited no sex differences in [14C]oleate utilization. With maturation, total [14C]oleate utilization and triglyceride biosynthesis increased moderately in female cells and decreased markedly in male cells; the profound sex differences in adults were maximal by age 60 d. Fatty acid oxidation was little affected. Rats were castrated at age 30 d, and received estradiol, testosterone, or no hormone until age 60 d, when hepatocyte [14C]oleate utilization was studied. Castration virtually eliminated maturational changes and blunted the sex differences in adults. Estradiol or testosterone largely reproduced the appropriate adult pattern of [14C]oleate utilization regardless of the genotypic sex of the treated animal. In immature females and males, total cytosolic FABP concentrations were similar. In 60-d-old animals, there was a striking correlation among all groups (females, males, castrates, and hormone-treated) between mean cytosolic FABP concentration on the one hand, and mean total [14C]oleate utilization (r = 0.91) and incorporation into triglycerides (r = 0.94) on the other. In 30-d-old animals rates of [14C

  1. Unexpectedly high indoor hydroxyl radical concentrations associated with nitrous acid.

    PubMed

    Gómez Alvarez, Elena; Amedro, Damien; Afif, Charbel; Gligorovski, Sasho; Schoemaecker, Coralie; Schoemacker, Coralie; Fittschen, Christa; Doussin, Jean-Francois; Wortham, Henri

    2013-08-13

    The hydroxyl (OH) radical is the most important oxidant in the atmosphere since it controls its self-oxidizing capacity. The main sources of OH radicals are the photolysis of ozone and the photolysis of nitrous acid (HONO). Due to the attenuation of solar radiation in the indoor environment, the possibility of OH formation through photolytic pathways indoors has been ignored up to now. In the indoor air, the ozonolysis of alkenes has been suggested as an alternative route of OH formation. Models and indirect measurements performed up to now according to this hypothesis suggest concentrations of OH radicals on the order of 10(4)-10(5) molecules per cubic centimeter. Here, we present direct measurements of significant amounts of OH radicals of up to 1.8⋅10(6) molecules per cubic centimeter during an experimental campaign carried out in a school classroom in Marseille. This concentration is on the same order of magnitude of outdoor OH levels in the urban scenario. We also show that photolysis of HONO is an important source of OH radicals indoors under certain conditions (i.e., direct solar irradiation inside the room). Additionally, the OH concentrations were found to follow a linear dependence with the product J(HONO)⋅[HONO]. This was also supported by using a simple quasiphotostationary state model on the OH radical budget. These findings force a change in our understanding of indoor air quality because the reactivity linked to OH would involve formation of secondary species through chemical reactions that are potentially more hazardous than the primary pollutants in the indoor air.

  2. Unexpectedly high indoor hydroxyl radical concentrations associated with nitrous acid

    PubMed Central

    Gómez Alvarez, Elena; Amedro, Damien; Afif, Charbel; Gligorovski, Sasho; Schoemaecker, Coralie; Fittschen, Christa; Doussin, Jean-Francois; Wortham, Henri

    2013-01-01

    The hydroxyl (OH) radical is the most important oxidant in the atmosphere since it controls its self-oxidizing capacity. The main sources of OH radicals are the photolysis of ozone and the photolysis of nitrous acid (HONO). Due to the attenuation of solar radiation in the indoor environment, the possibility of OH formation through photolytic pathways indoors has been ignored up to now. In the indoor air, the ozonolysis of alkenes has been suggested as an alternative route of OH formation. Models and indirect measurements performed up to now according to this hypothesis suggest concentrations of OH radicals on the order of 104–105 molecules per cubic centimeter. Here, we present direct measurements of significant amounts of OH radicals of up to 1.8⋅106 molecules per cubic centimeter during an experimental campaign carried out in a school classroom in Marseille. This concentration is on the same order of magnitude of outdoor OH levels in the urban scenario. We also show that photolysis of HONO is an important source of OH radicals indoors under certain conditions (i.e., direct solar irradiation inside the room). Additionally, the OH concentrations were found to follow a linear dependence with the product J(HONO)⋅[HONO]. This was also supported by using a simple quasiphotostationary state model on the OH radical budget. These findings force a change in our understanding of indoor air quality because the reactivity linked to OH would involve formation of secondary species through chemical reactions that are potentially more hazardous than the primary pollutants in the indoor air. PMID:23898188

  3. 21 CFR 146.148 - Reduced acid frozen concentrated orange juice.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Reduced acid frozen concentrated orange juice. 146... Canned Fruit Juices and Beverages § 146.148 Reduced acid frozen concentrated orange juice. (a) Reduced acid frozen concentrated orange juice is the food that complies with the requirements for...

  4. 21 CFR 146.148 - Reduced acid frozen concentrated orange juice.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Reduced acid frozen concentrated orange juice. 146... Canned Fruit Juices and Beverages § 146.148 Reduced acid frozen concentrated orange juice. (a) Reduced acid frozen concentrated orange juice is the food that complies with the requirements for...

  5. 21 CFR 146.148 - Reduced acid frozen concentrated orange juice.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Reduced acid frozen concentrated orange juice. 146... Canned Fruit Juices and Beverages § 146.148 Reduced acid frozen concentrated orange juice. (a) Reduced acid frozen concentrated orange juice is the food that complies with the requirements for...

  6. 21 CFR 146.148 - Reduced acid frozen concentrated orange juice.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Reduced acid frozen concentrated orange juice. 146... Canned Fruit Juices and Beverages § 146.148 Reduced acid frozen concentrated orange juice. (a) Reduced acid frozen concentrated orange juice is the food that complies with the requirements for...

  7. 21 CFR 146.148 - Reduced acid frozen concentrated orange juice.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Reduced acid frozen concentrated orange juice. 146... Canned Fruit Juices and Beverages § 146.148 Reduced acid frozen concentrated orange juice. (a) Reduced acid frozen concentrated orange juice is the food that complies with the requirements for...

  8. Color Change of Sudan III against Concentrated Sulfuric Acid in Acetonitrile and Quantification for a Small Amount of Concentrated Sulfuric Acid.

    PubMed

    Sakurai, Takao; Kurata, Shoji; Ogino, Kenji

    2016-01-01

    The color-changing phenomenon of hydrophobic bisazo dye, Sudan III in an acetonitrile solution against the addition of concentrated sulfuric acid has been discovered and the chromic properties investigated. Based on observations, a novel quantification method of concentrated sulfuric acid has been developed. Sudan III changes its color from orange to blue against a small volume of sulfuric acid, and the acetonitrile solution of Sudan III is the most suitable for observing the color-change phenomenon. (1)H-NMR and UV-Vis spectroscopic studies showed that the color-change mechanism of Sudan III against sulfuric acid is due to the protonation of the dye by sulfuric acid. This phenomenon is applicable to the quantification of concentrated sulfuric acid by introducing the Hammett acidity function. The proposed method requires only a small amount of the sample, 0.04 mL, and enables rapid quantification.

  9. Dissolution of plutonium oxide in nitric acid at high hydrofluoric acid concentrations

    SciTech Connect

    Kazanjian, A.R.; Stevens, J.R.

    1984-06-15

    The dissolution of plutonium dioxide in nitirc acid (HNO/sub 3/) at high hydrofluoric acid (HF) concentrations has been investigated. Dissolution rate curves were obtained using 12M HNO/sub 3/ and HF at concentrations varying from 0.05 to 1.0 molar. The dissolution rate increased with HF concentration up to 0.2M and then decreased at higher concentrations. There was very little plutonium dissolved at 0.7 and 1.0M HF because of the formation of insoluble PuF/sub 4/. Various oxidizing agents were added to 12M HNO/sub 3/-1M HF dissolvent to oxidize Pu(IV) to Pu(VI) and prevent the formation of PuF/sub 4/. Ceric (Ce(IV)) and silver (Ag(II)) ions were the most effective in dissolving PuO/sub 2/. Although these two oxidants greatly increased the dissolution rate, the rates were not as rapid as those obtained with 12M HNO/sub 3/-0.2M HF.

  10. Amino Acid Composition of an Organic Brown Rice Protein Concentrate and Isolate Compared to Soy and Whey Concentrates and Isolates.

    PubMed

    Kalman, Douglas S

    2014-06-30

    A protein concentrate (Oryzatein-80™) and a protein isolate (Oryzatein-90™) from organic whole-grain brown rice were analyzed for their amino acid composition. Two samples from different batches of Oryzatein-90™ and one sample of Oryzatein-80™ were provided by Axiom Foods (Los Angeles, CA, USA). Preparation and analysis was carried out by Covance Laboratories (Madison, WI, USA). After hydrolysis in 6-N hydrochloric acid for 24 h at approximately 110 °C and further chemical stabilization, samples were analyzed by HPLC after pre-injection derivitization. Total amino acid content of both the isolate and the concentrate was approximately 78% by weight with 36% essential amino acids and 18% branched-chain amino acids. These results are similar to the profiles of raw and cooked brown rice except in the case of glutamic acid which was 3% lower in the isolate and concentrate. The amino acid content and profile of the Oryzatein-90™ isolate was similar to published values for soy protein isolate but the total, essential, and branched-chain amino acid content of whey protein isolate was 20%, 39% and 33% greater, respectively, than that of Oryzatein-90™. These results provide a valuable addition to the nutrient database of protein isolates and concentrates from cereal grains.

  11. Various concentrations of erucic acid in mustard oil and mustard.

    PubMed

    Wendlinger, Christine; Hammann, Simon; Vetter, Walter

    2014-06-15

    Erucic acid is a typical constituent of mustard or rape. Foodstuff with a high content of erucic acid is considered undesirable for human consumption because it has been linked to myocardial lipidosis and heart lesions in laboratory rats. As a result, several countries have restricted its presence in oils and fats. In this study, the erucic acid content in several mustard oils and prepared mustard samples from Germany and Australia was determined. Seven of nine mustard oil samples exceeded the permitted maximum levels established for erucic acid (range: 0.3-50.8%, limit: 5%). The erucic acid content in mustard samples (n=15) varied from 14% to 33% in the lipids. Two servings (i.e. 20 g) of the mustards with the highest erucic acid content already surpassed the tolerable daily intake established by Food Standards Australia New Zealand. However, a careful selection of mustard cultivars could lower the nutritional intake of erucic acid.

  12. Modulation of absence seizures by branched-chain amino acids: correlation with brain amino acid concentrations.

    PubMed

    Dufour, F; Nalecz, K A; Nalecz, M J; Nehlig, A

    2001-07-01

    The occurrence of absence seizures might be due to a disturbance of the balance between excitatory and inhibitory neurotransmissions in the thalamo-cortical loop. In this study, we explored the consequences of buffering the glutamate content of brain cells on the occurrence and duration of seizures in Genetic Absence Epilepsy Rats from Strasbourg (GAERS), a genetic model of generalized non-convulsive epilepsy. Branched-chain amino acids (BCAAs) and alpha-ketoisocaproate (alpha-KIC), the ketoacid of leucine were repeatedly shown to have a critical role in brain glutamate metabolism. Thus, GAERS were injected by intraperitoneal (i.p.) or intracerebroventricular (i.c.v.) route with these compounds, then the effects on seizures were evaluated on the electroencephalographic recording. We also measured the concentration of amino acids in thalamus and cortex after an i.p. injection of leucine or alpha-KIC. Intracerebroventricular injections of leucine or alpha-KIC did not influence the occurrence of seizures, possibly because the substances reached only the cortex. BCAAs and alpha-KIC, injected intraperitoneally, increased the number of seizures whereas they had only a slight effect on their duration. Leucine and alpha-KIC decreased the concentration of glutamate in thalamus and cortex without affecting GABA concentrations. Thus, BCAAs and alpha-KIC, by decreasing the effects of glutamatergic neurotransmission could facilitate those of GABAergic neurotransmission, which is known to increase the occurrence of seizures in GAERS.

  13. Effect of acid concentration and treatment time on acid-alcohol modified jackfruit seed starch properties.

    PubMed

    Dutta, Himjyoti; Paul, Sanjib Kumar; Kalita, Dipankar; Mahanta, Charu Lata

    2011-09-15

    The properties of starch extracted from jackfruit (Artocarpus heterophyllus Lam.) seeds, collected from west Assam after acid-alcohol modification by short term treatment (ST) for 15-30min with concentrated hydrochloric acid and long term treatment (LT) for 1-15days with 1M hydrochloric acid, were investigated. Granule density, freeze thaw stability, solubility and light transmittance of the treated starches increased. A maximum decrease in the degree of polymerisation occurred in ST of 30min (2607.6). Jackfruit starch had 27.1±0.04% amylose content (db), which in ST initially decreased and then increased with the severity of treatment; in LT the effect was irregular. The pasting profile and granule morphology of the treated samples were severely modified. Native starch had the A-type crystalline pattern and crystalline structure increased on treatment. FTIR spectra revealed slight changes in bond stretching and bending. Colour measurement indicated that whiteness increased on treatment. Acid modified jackfruit seed starch can have applications in the food industry.

  14. Effects of running the Bostom Marathon on plasma concentrations of large neutral amino acids

    NASA Technical Reports Server (NTRS)

    Conlay, L. A.; Wurtman, R. J.; Lopez G-Coviella, I.; Blusztajn, J. K.; Vacanti, C. A.; Logue, M.; During, M.; Caballero, B.; Maher, T. J.; Evoniuk, G.

    1989-01-01

    Plasma large neutral amino acid concentrations were measured in thirty-seven subjects before and after completing the Boston Marathon. Concentrations of tyrosine, phenylalanine, and methionine increased, as did their 'plasma ratios' (i.e., the ratio of each amino acid's concentration to the summed plasma concentrations of the other large neutral amino acids which compete with it for brain uptake). No changes were noted in the plasma concentrations of tryptophan, leucine, isoleucine, nor valine; however, the 'plasma ratios' of valine, leucine, and isoleucine all decreased. These changes in plasma amino acid patterns may influence neurotransmitter synthesis.

  15. Equine endurance exercise alters serum branched-chain amino acid and alanine concentrations.

    PubMed

    Trottier, N L; Nielsen, B D; Lang, K J; Ku, P K; Schott, H C

    2002-09-01

    Six 2-year-old Arabian horses were used to determine whether 60 km prolonged endurance exercise (approximately 4 h) alters amino acid concentrations in serum and muscle, and the time required for serum amino acid concentrations to return to basal resting values. Blood and muscle samples were collected throughout exercise and during a 3 day recovery period. Isoleucine concentration in muscle tended to increase and leucine and valine did not change due to exercise. Serum alanine concentrations did not increase immediately after exercise, but increased at 24, 48 and 72 h postexercise. Serum isoleucine, leucine, and valine concentrations decreased after exercise and time required to reach pre-exercising concentrations was 48 h. In conclusion, endurance exercise in the horse decreases serum isoleucine, leucine, and valine concentrations, and increases serum alanine concentration. The decrease in serum branched-chain amino acid concentrations did not correspond to a measurable increase in total muscle branched-chain amino acid concentrations.

  16. Influence of bleaching on flavor of 34% whey protein concentrate and residual benzoic acid concentration in dried whey products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous studies have shown that bleaching negatively affects the flavor of 70% whey protein concentrate (WPC70), but bleaching effects on lower-protein products have not been established. Benzoyl peroxide (BP), a whey bleaching agent, degrades to benzoic acid (BA) and may elevate BA concentrations...

  17. Influence of Bleaching on Flavor of 34% Whey Protein Concentrate and Residual Benzoic Acid Concentration in Dried Whey Proteins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous studies have shown that bleaching negatively affects the flavor of 70% whey protein concentrate (WPC70), but bleaching effects on lower-protein products have not been established. Benzoyl peroxide (BP), a whey bleaching agent, degrades to benzoic acid (BA) and may elevate BA concentrations...

  18. A hybrid SVM-FFA method for prediction of monthly mean global solar radiation

    NASA Astrophysics Data System (ADS)

    Shamshirband, Shahaboddin; Mohammadi, Kasra; Tong, Chong Wen; Zamani, Mazdak; Motamedi, Shervin; Ch, Sudheer

    2016-07-01

    In this study, a hybrid support vector machine-firefly optimization algorithm (SVM-FFA) model is proposed to estimate monthly mean horizontal global solar radiation (HGSR). The merit of SVM-FFA is assessed statistically by comparing its performance with three previously used approaches. Using each approach and long-term measured HGSR, three models are calibrated by considering different sets of meteorological parameters measured for Bandar Abbass situated in Iran. It is found that the model (3) utilizing the combination of relative sunshine duration, difference between maximum and minimum temperatures, relative humidity, water vapor pressure, average temperature, and extraterrestrial solar radiation shows superior performance based upon all approaches. Moreover, the extraterrestrial radiation is introduced as a significant parameter to accurately estimate the global solar radiation. The survey results reveal that the developed SVM-FFA approach is greatly capable to provide favorable predictions with significantly higher precision than other examined techniques. For the SVM-FFA (3), the statistical indicators of mean absolute percentage error (MAPE), root mean square error (RMSE), relative root mean square error (RRMSE), and coefficient of determination ( R 2) are 3.3252 %, 0.1859 kWh/m2, 3.7350 %, and 0.9737, respectively which according to the RRMSE has an excellent performance. As a more evaluation of SVM-FFA (3), the ratio of estimated to measured values is computed and found that 47 out of 48 months considered as testing data fall between 0.90 and 1.10. Also, by performing a further verification, it is concluded that SVM-FFA (3) offers absolute superiority over the empirical models using relatively similar input parameters. In a nutshell, the hybrid SVM-FFA approach would be considered highly efficient to estimate the HGSR.

  19. Adipose Tissue Free Fatty Acid Storage In Vivo: Effects of Insulin Versus Niacin as a Control for Suppression of Lipolysis.

    PubMed

    Ali, Asem H; Mundi, Manpreet; Koutsari, Christina; Bernlohr, David A; Jensen, Michael D

    2015-08-01

    Insulin stimulates the translocation fatty acid transport protein 1 (FATP1) to plasma membrane, and thus greater free fatty acid (FFA) uptake, in adipocyte cell models. Whether insulin stimulates greater FFA clearance into adipose tissue in vivo is unknown. We tested this hypothesis by comparing direct FFA storage in subcutaneous adipose tissue during insulin versus niacin-medicated suppression of lipolysis. We measured direct FFA storage in abdominal and femoral subcutaneous fat in 10 and 11 adults, respectively, during euglycemic hyperinsulinemia or after oral niacin to suppress FFA compared with 11 saline control experiments. Direct palmitate storage was assessed using a [U-(13)C]palmitate infusion to measure palmitate kinetics and an intravenous palmitate radiotracer bolus/timed biopsy. Plasma palmitate concentrations and flux were suppressed to 23 ± 3 and 26 ± 5 µmol ⋅ L(-1) (P = 0.91) and 44 ± 4 and 39 ± 5 µmol ⋅ min(-1) (P = 0.41) in the insulin and niacin groups, respectively, much less (P < 0.001) than the saline control group (102 ± 8 and 104 ± 12 µmol ⋅ min(-1), respectively). In the insulin, niacin, and saline groups, abdominal palmitate storage rates were 0.25 ± 0.05 vs. 0.25 ± 0.07 vs. 0.32 ± 0.05 µmol ⋅ kg adipose lipid(-1) ⋅ min(-1), respectively (P = NS), and femoral adipose storage rates were 0.19 ± 0.06 vs. 0.20 ± 0.05 vs. 0.31 ± 0.05 µmol ⋅ kg adipose lipid(-1) ⋅ min(-1), respectively (P = NS). In conclusion, insulin does not increase FFA storage in adipose tissue compared with niacin, which suppresses lipolysis via a different pathway.

  20. Adipose Tissue Free Fatty Acid Storage In Vivo: Effects of Insulin Versus Niacin as a Control for Suppression of Lipolysis

    PubMed Central

    Ali, Asem H.; Mundi, Manpreet; Koutsari, Christina; Bernlohr, David A.

    2015-01-01

    Insulin stimulates the translocation fatty acid transport protein 1 (FATP1) to plasma membrane, and thus greater free fatty acid (FFA) uptake, in adipocyte cell models. Whether insulin stimulates greater FFA clearance into adipose tissue in vivo is unknown. We tested this hypothesis by comparing direct FFA storage in subcutaneous adipose tissue during insulin versus niacin-medicated suppression of lipolysis. We measured direct FFA storage in abdominal and femoral subcutaneous fat in 10 and 11 adults, respectively, during euglycemic hyperinsulinemia or after oral niacin to suppress FFA compared with 11 saline control experiments. Direct palmitate storage was assessed using a [U-13C]palmitate infusion to measure palmitate kinetics and an intravenous palmitate radiotracer bolus/timed biopsy. Plasma palmitate concentrations and flux were suppressed to 23 ± 3 and 26 ± 5 µmol ⋅ L−1 (P = 0.91) and 44 ± 4 and 39 ± 5 µmol ⋅ min−1 (P = 0.41) in the insulin and niacin groups, respectively, much less (P < 0.001) than the saline control group (102 ± 8 and 104 ± 12 µmol ⋅ min−1, respectively). In the insulin, niacin, and saline groups, abdominal palmitate storage rates were 0.25 ± 0.05 vs. 0.25 ± 0.07 vs. 0.32 ± 0.05 µmol ⋅ kg adipose lipid−1 ⋅ min−1, respectively (P = NS), and femoral adipose storage rates were 0.19 ± 0.06 vs. 0.20 ± 0.05 vs. 0.31 ± 0.05 µmol ⋅ kg adipose lipid−1 ⋅ min−1, respectively (P = NS). In conclusion, insulin does not increase FFA storage in adipose tissue compared with niacin, which suppresses lipolysis via a different pathway. PMID:25883112

  1. Storage of Circulating Free Fatty Acid in Adipose Tissue of Postabsorptive Humans

    PubMed Central

    Koutsari, Christina; Ali, Asem H.; Mundi, Manpreet S.; Jensen, Michael D.

    2011-01-01

    OBJECTIVE Preferential upper-body fat gain, a typical male pattern, is associated with a greater cardiometabolic risk. Regional differences in lipolysis and meal fat storage cannot explain sex differences in body fat distribution. We examined the potential role of the novel free fatty acid (FFA) storage pathway in determining body fat distribution in postabsorptive humans and whether adipocyte lipogenic proteins (CD36, acyl-CoA synthetases, and diacylglycerol acyltransferase) predict differences in FFA storage. RESEARCH DESIGN AND METHODS Rates of postabsorptive FFA (palmitate) storage into upper-body subcutaneous (UBSQ) and lower-body subcutaneous (LBSQ) fat were measured in 28 men and 53 premenopausal women. Stable and radiolabeled palmitate tracers were intravenously infused followed by subcutaneous fat biopsies. Body composition was assessed with a combination of dual-energy X-ray absorptiometry and computed tomography. RESULTS Women had greater FFA (palmitate) storage than men in both UBSQ (0.37 ± 0.15 vs. 0.27 ± 0.18 μmol · kg−1 · min−1, P = 0.0001) and LBSQ (0.42 ± 0.19 vs. 0.22 ± 0.11 μmol · kg−1 · min−1, P < 0.0001) fat. Palmitate storage rates were significantly greater in LBSQ than UBSQ fat in women, whereas the opposite was true in men. Plasma palmitate concentration positively predicted palmitate storage in both depots and sexes. Adipocyte CD36 content predicted UBSQ palmitate storage and sex-predicted storage in LBSQ fat. Palmitate storage rates per kilogram fat did not decrease as a function of fat mass, whereas lipolysis did. CONCLUSIONS The FFA storage pathway, which had remained undetected in postabsorptive humans until recently, can have considerable, long-term, and sex-specific effects on body fat distribution. It can also offer a way of protecting the body from excessive circulating FFA in obesity. PMID:21659500

  2. Elevational Variation in Soil Amino Acid and Inorganic Nitrogen Concentrations in Taibai Mountain, China

    PubMed Central

    Yang, Xin; Zhu, Lianfeng; Zhang, Junhua; Jin, Qianyu; Wu, Lianghuan

    2016-01-01

    Amino acids are important sources of soil organic nitrogen (N), which is essential for plant nutrition, but detailed information about which amino acids predominant and whether amino acid composition varies with elevation is lacking. In this study, we hypothesized that the concentrations of amino acids in soil would increase and their composition would vary along the elevational gradient of Taibai Mountain, as plant-derived organic matter accumulated and N mineralization and microbial immobilization of amino acids slowed with reduced soil temperature. Results showed that the concentrations of soil extractable total N, extractable organic N and amino acids significantly increased with elevation due to the accumulation of soil organic matter and the greater N content. Soil extractable organic N concentration was significantly greater than that of the extractable inorganic N (NO3−-N + NH4+-N). On average, soil adsorbed amino acid concentration was approximately 5-fold greater than that of the free amino acids, which indicates that adsorbed amino acids extracted with the strong salt solution likely represent a potential source for the replenishment of free amino acids. We found no appreciable evidence to suggest that amino acids with simple molecular structure were dominant at low elevations, whereas amino acids with high molecular weight and complex aromatic structure dominated the high elevations. Across the elevational gradient, the amino acid pool was dominated by alanine, aspartic acid, glycine, glutamic acid, histidine, serine and threonine. These seven amino acids accounted for approximately 68.9% of the total hydrolyzable amino acid pool. The proportions of isoleucine, tyrosine and methionine varied with elevation, while soil major amino acid composition (including alanine, arginine, aspartic acid, glycine, histidine, leucine, phenylalanine, serine, threonine and valine) did not vary appreciably with elevation (p>0.10). The compositional similarity of many

  3. Regulation of uterine and umbilical amino acid uptakes by maternal amino acid concentrations.

    PubMed

    Thureen, P J; Anderson, S M; Hay, W W

    2000-09-01

    We tested the hypothesis that decreased fetal amino acid (AA) supply, produced by maternal hypoaminoacidemia (low AA) during hyperglycemia (HG), is reversible with maternal AA infusion and regulates fetal insulin concentration ([I]). We measured net uterine and umbilical AA uptakes during maternal HG/low AA concentration ([AA]) and after maternal intravenous infusion of a mixed AA solution. After 5 days HG, all maternal [AA] except glycine were decreased >50%, particularly essential [AA] (P < 0.00005). Most fetal [AA] also were decreased, especially branched-chain AA (P < 0.001). Maternal AA infusion increased net uterine uptakes of Val, Leu, Ile, Met, and Ser and net umbilical uptakes of Val, Leu, Ile, Met, Phe, and Arg but did not change net uteroplacental uptake of any AA. Fetal [I] increased 55 +/- 14%, P < 0.001, with correction of fetal [AA], despite the lack of change in fetal glucose concentration. Thus generalized maternal hypoaminoacidemia decreases uterine and umbilical uptakes of primarily the essential AA and decreases fetal branched-chain [AA]. These changes are reversed with correction of maternal [AA], which also increases fetal [I].

  4. [Concentration of hydrochloric acid and pepsin in gastric juice in dogs after starvation and refeeding].

    PubMed

    Andreeva, Iu V; Polenov, S A

    2005-03-01

    Feeding fogs with meat after a 3-day period of starvation increased hydrochloric acid concentration with subsequent return of the parameter to normal values. Under the same conditions, pepsin concentration decreased and raised up after re-feeding. Histamine administration following the starvation decreased hydrochloric acid concentration with subsequent normalising. In three days after re-feeding and histamine administration, pepsin concentration drooped owing, probably, to a decrease of parietal cell H2-receptor affinity to histamine. Pentagastrin administration after the starvation increased hydrochloric acid concentration. The findings suggest G-cell function inhibition occurring after a 3-day starvation which is important for the stomach mucous membrane protection.

  5. The serum uric acid concentration is not causally linked to diabetic nephropathy in type 1 diabetes.

    PubMed

    Ahola, Aila J; Sandholm, Niina; Forsblom, Carol; Harjutsalo, Valma; Dahlström, Emma; Groop, Per-Henrik

    2017-02-21

    Previous studies have shown a relationship between uric acid concentration and progression of renal disease. Here we studied causality between the serum uric acid concentration and progression of diabetic nephropathy in 3895 individuals with type 1 diabetes in the FinnDiane Study. The renal status was assessed with the urinary albumin excretion rate and estimated glomerular filtration rate (eGFR) at baseline and at the end of the follow-up. Based on previous genomewide association studies on serum uric acid concentration, 23 single nucleotide polymorphisms (SNPs) with good imputation quality were selected for the SNP score. This score was used to assess the causality between serum uric acid and renal complications using a Mendelian randomization approach. At baseline, the serum uric acid concentration was higher with worsening renal status. In multivariable Cox regression analyses, baseline serum uric acid concentration was not independently associated with progression of diabetic nephropathy over a mean follow-up of 7 years. However, over the same period, baseline serum uric acid was independently associated with the decline in eGFR. In the cross-sectional logistic regression analyses, the SNP score was associated with the serum uric acid concentration. Nevertheless, the Mendelian randomization showed no causality between uric acid and diabetic nephropathy, eGFR categories, or eGFR as a continuous variable. Thus, our results suggest that the serum uric acid concentration is not causally related to diabetic nephropathy but is a downstream marker of kidney damage.

  6. Electrochemical Hydrogen Concentrator for Phosphoric Acid Fuel Cells.

    DTIC Science & Technology

    1987-11-01

    cathode, no systematic relationship between contaminant concentrations and operating conditions could be discerned in any of the cell configurations... the cathode. No * systematic relationship between contaminant concentrations in the product gas and operating conditions or anode catalyst could be...34-l,, PElO3.-l ’ T DISCLAIMERS THE FINDINGS IN THIS REPORT ARE NOT TO BE CONSTRUED AS AN OFFICIAL DEPARTMENT OF THE ARMY POSITION, UNLESS SO DESIGNATED

  7. Free fatty acids normalize a rosiglitazone-induced visfatin release.

    PubMed

    Haider, Dominik G; Mittermayer, Friedrich; Schaller, Georg; Artwohl, Michaela; Baumgartner-Parzer, Sabina M; Prager, Gerhard; Roden, Michael; Wolzt, Michael

    2006-11-01

    The detrimental effect of elevated free fatty acids (FFAs) on insulin sensitivity can be improved by thiazolidinediones (TZDs) in patients with type 2 diabetes mellitus. It is unknown whether this salutary action of TZD is associated with altered release of the insulin-mimetic adipocytokine visfatin. In this study, we investigated whether visfatin concentrations are altered by FFA and TZD treatment. In a randomized, double-blind, placebo-controlled, parallel-group study 16 healthy volunteers received an infusion of triglycerides/heparin to increase plasma FFA after 3 wk of treatment with rosiglitazone (8 mg/day, n = 8) or placebo (n = 8), and circulating plasma visfatin was measured. As a corollary, human adipocytes were incubated with synthetic fatty acids and rosiglitazone to assess visfatin release in vitro. The results were that rosiglitazone treatment increased systemic plasma visfatin concentrations from 0.6 +/- 0.1 to 1.7 +/- 0.2 ng/ml (P < 0.01). Lipid infusion caused a marked elevation of plasma FFA but had no effect on circulating visfatin in controls. In contrast, elevated visfatin concentrations in subjects receiving rosiglitazone were normalized by lipid infusion. In isolated adipocytes, visfatin was released into supernatant medium by acute addition and long-term treatment of rosiglitazone. This secretion was blocked by synthetic fatty acids and by inhibition of phosphatidylinositol 3-kinase or Akt. In conclusion, release of the insulin-mimetic visfatin may represent a major mechanism of metabolic TZD action. The presence of FFA antagonizes this action, which may have implications for visfatin bioactivity.

  8. Summary and implications of reported amino acid concentrations in the Murchison meteorite

    SciTech Connect

    Shock, E.L.; Schulte, M.D. )

    1990-11-01

    A study of literature reports of the concentrations of amino acids in extracts from the Murchison meteorite shows that many of the concentration ratios are constant. There are two possible interpretations of these ratios. One is that they are controlled by the pathways through which the amino acids formed, from which it follows that the amino acids are distributed in the same proportions throughout the meteorite. The other interpretation is that the ratios result from the analytical procedures used to extract the amino acids from the meteorite. These methods rely heavily on high-temperature (100{degree}C) aqueous extraction and subsequent high-temperature acid hydrolysis. A correlation was observed in the present study between the relative concentrations of several amino acids in the meteorite extracts and their relative aqueous solubilities at 100{degree}C. The extract solutions are dilute, and far from the saturation limits, but these correlations suggest that the sampling procedure affects directly the reported concentrations for these amino acids. If the extraction process does not bias the results, and all extractable amino acids are removed from meteorite samples, then the properties of amino acids which control both their solubilities and their concentrations in the meteorite need to be established. The possibility of sampling bias needs to be tested experimentally before concluding that extraction is complete, and that the constant relative abundances indicate that the relative concentrations of amino acids are homogeneous in the meteorite.

  9. Serum amino acid concentrations in patients receiving total parenteral nutrition with an amino acid plus dextrose mixture.

    PubMed

    Philcox, J C; Hartley, T F; Worthley, L I; Thomas, D W

    1984-01-01

    The results of monitoring the serum amino acid concentrations during three infusion regimens using a 5:4 mixture of 70% glucose and the synthetic L-amino acid solution, Synthamin 17 (Travasol) are reported. Twelve stabilized patients received continuous total parenteral nutrition (TPN), eight of whom were subsequently placed on a second regimen of cyclical feeding. A separate group of five patients was infused with amino acids, both with and without simultaneous glucose. The serum amino acid concentrations indicated that the supply of valine, leucine, isoleucine, lysine, and histidine, and the synthesis of taurine from the infused methionine was suboptimal, particularly if the period of TPN was prolonged. The synthesis of tyrosine from phenylalanine appeared to be inversely proportional to the infusion rate of the TPN mixture, in particular the glucose component, resulting in depressed tyrosine and increased phenylalanine concentrations in serum during continuous iv nutrition. Cyclical infusions, on the other hand, permitted the tyrosine and phenylalanine concentrations to return to normal during the noninfusion stage of the cycle. Amino acid measurements enabled us to design an amino acids additive mixture which normalized the serum concentrations in three long-term home parenteral nutrition patients. As a result of these investigations serum amino acid measurements are used routinely to monitor the efficacy of TPN and accommodate any specific amino acid requirements of individual patients.

  10. Using Conductivity Measurements to Determine the Identities and Concentrations of Unknown Acids: An Inquiry Laboratory Experiment

    ERIC Educational Resources Information Center

    Smith, K. Christopher; Garza, Ariana

    2015-01-01

    This paper describes a student designed experiment using titrations involving conductivity measurements to identify unknown acids as being either HCl or H[subscript 2]SO[subscript 4], and to determine the concentrations of the acids, thereby improving the utility of standard acid-base titrations. Using an inquiry context, students gain experience…

  11. Understanding Particle Formation: Solubility of Free Fatty Acids as Polysorbate 20 Degradation Byproducts in Therapeutic Monoclonal Antibody Formulations.

    PubMed

    Doshi, Nidhi; Demeule, Barthélemy; Yadav, Sandeep

    2015-11-02

    The purpose of this work was to determine the aqueous solubilities at 2-8 °C of the major free fatty acids (FFAs) formed by polysorbate 20 (PS20) degradation and identify possible ways to predict, delay, or mitigate subsequent particle formation in monoclonal antibody (mAb) formulations. The FFA solubility limits at 2-8 °C were determined by titrating known amounts of FFA in monoclonal antibody formulations and identifying the FFA concentration leading to visible and subvisible particle formation. The solubility limits of lauric, myristic, and palmitic acids at 2-8 °C were 17 ± 1 μg/mL, 3 ± 1 μg/mL, and 1.5 ± 0.5 μg/mL in a formulation containing 0.04% (w/v) PS20 at pH 5.4 and >22 μg/mL, 3 ± 1 μg/mL, and 0.75 ± 0.25 μg/mL in a formulation containing 0.02% (w/v) PS20 at pH 6.0. For the first time, a 3D correlation between FFA solubility, PS20 concentration, and pH has been reported providing a rational approach for the formulator to balance these with regard to potential particle formation. The results suggest that the lower solubilities of the longer chain FFAs, generated from degradation of the stearate, palmitate, and myristate fraction of PS20, is the primary cause of seeding and subsequent FFA precipitation rather than the most abundant lauric acid.

  12. High plasma uric acid concentration: causes and consequences

    PubMed Central

    2012-01-01

    High plasma uric acid (UA) is a precipitating factor for gout and renal calculi as well as a strong risk factor for Metabolic Syndrome and cardiovascular disease. The main causes for higher plasma UA are either lower excretion, higher synthesis or both. Higher waist circumference and the BMI are associated with higher insulin resistance and leptin production, and both reduce uric acid excretion. The synthesis of fatty acids (tryglicerides) in the liver is associated with the de novo synthesis of purine, accelerating UA production. The role played by diet on hyperuricemia has not yet been fully clarified, but high intake of fructose-rich industrialized food and high alcohol intake (particularly beer) seem to influence uricemia. It is not known whether UA would be a causal factor or an antioxidant protective response. Most authors do not consider the UA as a risk factor, but presenting antioxidant function. UA contributes to > 50% of the antioxidant capacity of the blood. There is still no consensus if UA is a protective or a risk factor, however, it seems that acute elevation is a protective factor, whereas chronic elevation a risk for disease. PMID:22475652

  13. Amino acid concentrations in plasma and erythrocytes in aregeneratory and haemolytic anaemias.

    PubMed

    Seip, M; Lindemann, R; Gjesdahl, P; Gjessing, L R

    1975-10-01

    The concentrations of unbound amino acids in erythrocytes and in plasma from 7 normal individuals, 11 patients with various types of aregeneratory anaemia, and 4 patients with hereditary haemolytic anaemias were determined on a Technicon Amino Acid Analyzer (Perry et al 1970). Most amino acids were normally found in higher concentrations in plasma than intracellularly. Cystine, methionine and trypotophan were almost exclusively present in plasma. Aspartic acid, however, was mainly found in erythrocytes, and glutathione only in erythrocytes. Glutamic acid and ornithine were more concentrated in the cells, while glycine and asparagine showed approximately the same concentrations in erythrocytes as in plasma. In the patients, plasma amino acids showed little deviations from normal, but in the erythrocytes there were striking changes. Erythrocyte glutamic acid concentrations were moderately to markedly elevated in all patients studied, and glycine concentrations in 13 out of 15 patients. In addition, the following amino acids were increased intracellularly in more than one patient: glutamine (8 patients), serine (7), asparagine (5), threonine (4), taurine (3), alanine (2), valine (2), ornithine (2), lysine (2), citrulline (2). Aspartic acid was decreased in erythrocytes from 4 patients with aregeneratory and 1 with haemolytic anaemia.

  14. Water administration of medium-chain fatty acid caprylic acid produced variable efficacy against cecal Campylobacter jejuni concentrations in broilers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Campylobacter is one of the most common causes of foodborne illness, and poultry is considered a primary source of Campylobacter infections. Caprylic acid, an eight-carbon fatty acid, has been shown in previous studies to reduce enteric cecal Campylobacter concentrations in poultry when administere...

  15. Practical considerations in the concentration and recovery of spent nitration acids

    SciTech Connect

    Evans, C.M.

    1995-12-01

    Most organic nitrations employ sulphuric acid or oleum in the nitration acid. Even in rare nitric acid only nitrations, sulphuric acid is used as the dehydrating agent to produce 99% nitric acid. The used sulphuric acid is discharged in a diluted form contaminated with organic components and nitric/nitrous species. Pressures are emloyed to reconcentrate and reprocess such spent acids. Acid recovery and concentration is expensive. This paper discusses some of the aspects which must be considered when contemplating acid recovery. In the current industrial climate, acid recovery and recycle should be regarded as an integral part of a nitration process development rather than an afterthought. Case histories will be given in which such considerations influenced the course of the development of the nitration process itself. Emphasis will be placed on the importance of well planned bench and pilot scale test programmes.

  16. [Production of a concentrate of Mucor bacilliformis acid protease].

    PubMed

    Bottaro Castilla, H R; Waehner, R S; Meinardi, C A; Zalazar, C A; Fraile, E R

    1982-01-01

    A concentrate of milk-clotting enzyme was produced by culture of Mucor bacilliformis on wheat bran medium moistened to 120% water on dry bases with HC1 2 N solution. The wheat bran was autoclaved, spread on trays and inoculated with 5.10(6) spore/gr of dry bran. After 10 days of culture at 21 degrees C, the enzyme produced was extracted with water and adjusted to pH 4.4. The precipitation was performed with ethanol. The precipitate was dissolved in HCl solution (pH 4.5) and it was concentrated by dialysis against polyethylene glycol 20.000. The enzyme solution had a specific activity of 1123 units/mg. and it was tested in the elaboration of cream cheese.

  17. A Nationwide Examination of Middle School Enrollment in Agricultural Education and Membership in the National FFA Organization.

    ERIC Educational Resources Information Center

    Rossetti, Rosemarie; And Others

    The purpose of this study was to determine the status of middle and junior high school agricultural education and FFA (Future Farmers of America) programs. In spring 1991. questionnaires were sent to all state FFA Executive Secretaries (n=53); 52 returned questionnaires. Three teachers in each of 9 states identified as having middle or junior high…

  18. Relationship of Length of Vocational Agriculture Teacher Contract to Supervised Occupational Experience Program Scope and FFA Chapter Activity Level.

    ERIC Educational Resources Information Center

    Arrington, Larry R.

    A study examined the relationship of length of vocational agriculture teacher contract to supervised occupational experience program scope and Future Farmers of America (FFA) chapter activity level. A questionnaire measuring the activity level of the FFA chapter and soliciting information on various extraneous variables was administered to the…

  19. Organosulfates and organic acids in Arctic aerosols: speciation, annual variation and concentration levels

    NASA Astrophysics Data System (ADS)

    Hansen, A. M. K.; Kristensen, K.; Nguyen, Q. T.; Zare, A.; Cozzi, F.; Nøjgaard, J. K.; Skov, H.; Brandt, J.; Christensen, J. H.; Ström, J.; Tunved, P.; Krejci, R.; Glasius, M.

    2014-08-01

    Sources, composition and occurrence of secondary organic aerosols in the Arctic were investigated at Zeppelin Mountain, Svalbard, and Station Nord, northeastern Greenland, during the full annual cycle of 2008 and 2010, respectively. Speciation of organic acids, organosulfates and nitrooxy organosulfates - from both anthropogenic and biogenic precursors were in focus. A total of 11 organic acids (terpenylic acid, benzoic acid, phthalic acid, pinic acid, suberic acid, azelaic acid, adipic acid, pimelic acid, pinonic acid, diaterpenylic acid acetate and 3-methyl-1,2,3-butanetricarboxylic acid), 12 organosulfates and 1 nitrooxy organosulfate were identified in aerosol samples from the two sites using a high-performance liquid chromatograph (HPLC) coupled to a quadrupole Time-of-Flight mass spectrometer. At Station Nord, compound concentrations followed a distinct annual pattern, where high mean concentrations of organosulfates (47 ± 14 ng m-3) and organic acids (11.5 ± 4 ng m-3) were observed in January, February and March, contrary to considerably lower mean concentrations of organosulfates (2 ± 3 ng m-3) and organic acids (2.2 ± 1 ng m-3) observed during the rest of the year. At Zeppelin Mountain, organosulfate and organic acid concentrations remained relatively constant during most of the year at a mean concentration of 15 ± 4 ng m-3 and 3.9 ± 1 ng m-3, respectively. However during four weeks of spring, remarkably higher concentrations of total organosulfates (23-36 ng m-3) and total organic acids (7-10 ng m-3) were observed. Elevated organosulfate and organic acid concentrations coincided with the Arctic haze period at both stations, where northern Eurasia was identified as the main source region. Air mass transport from northern Eurasia to Zeppelin Mountain was associated with a 100% increase in the number of detected organosulfate species compared with periods of air mass transport from the Arctic Ocean, Scandinavia and Greenland. The results from this

  20. Career Development, Supervised Agricultural Experience, and FFA. The Connecticut Vocational Agriculture Education Curriculum.

    ERIC Educational Resources Information Center

    Mannebach, Alfred J.; And Others

    This curriculum guide was developed to help teachers and administrators in Connecticut Regional Vocational Agriculture Centers to update and upgrade their vocational agriculture curriculum in the areas of career development, supervised agricultural experience (SAE), and Future Farmers of America (FFA). The curriculum incorporates the competencies…

  1. Needed: Educational Objectives and Administrative Criteria for the National FFA Contests.

    ERIC Educational Resources Information Center

    Smith, Mack W.; Kahler, Alan A.

    1987-01-01

    The purpose of the study was to establish overall educational objectives and administrative criteria for the national Future Farmers of America (FFA) contests. Through a series of three questionnaires, input was received from a Delphi panel of 33 members that generated and identified objectives and criteria. (CH)

  2. A Historical Review of Leadership Development in the FFA and 4-H

    ERIC Educational Resources Information Center

    Hoover, Tracy S.; Scholl, Jan F.; Dunigan, Anne H.; Mamontova, Nadezhda

    2007-01-01

    FFA and 4-H are two youth-based organizations that cite leadership development as a key foundational component. The purpose of this study was to review and document the historical development of leadership events and activities in both programs. Evidence can be found of leadership development in schools, conferences, and camps. Leadership-related…

  3. Inhibition of hepatic gluconeogenesis by niflumic acid correlates with the concentration of the free form.

    PubMed

    Kelmer-Bracht, A M; Bracht, A

    1993-05-01

    Inhibition of hepatic gluconeogenesis by niflumic acid, a non-steroidal antiinflammatory drug, was measured in order to correlate the effect of the drug with the concentration of the free drug. The concentration of free drug was changed in two ways: (a) by changing the albumin concentration at a fixed total (free+bound) niflumic acid concentration; and, (b) by changing the drug concentration at a fixed albumin concentration. The degree of inhibition of gluconeogenesis by niflumic acid depends strictly on the concentration of the free drug, with half-maximal inhibition at 19.25 microM. This result is consistent with binding equilibrium in the extracellular space and with a flow-limited distribution between the extra- and intracellular spaces as proposed by our previous work.

  4. Effect of temperature and concentration on benzoyl peroxide bleaching efficacy and benzoic acid levels in whey protein concentrate.

    PubMed

    Smith, T J; Gerard, P D; Drake, M A

    2015-11-01

    Much of the fluid whey produced in the United States is a by-product of Cheddar cheese manufacture and must be bleached. Benzoyl peroxide (BP) is currently 1 of only 2 legal chemical bleaching agents for fluid whey in the United States, but benzoic acid is an unavoidable by-product of BP bleaching. Benzoyl peroxide is typically a powder, but new liquid BP dispersions are available. A greater understanding of the bleaching characteristics of BP is necessary. The objective of the study was to compare norbixin destruction, residual benzoic acid, and flavor differences between liquid whey and 80% whey protein concentrates (WPC80) bleached at different temperatures with 2 different benzoyl peroxides (soluble and insoluble). Two experiments were conducted in this study. For experiment 1, 3 factors (temperature, bleach type, bleach concentration) were evaluated for norbixin destruction using a response surface model-central composite design in liquid whey. For experiment 2, norbixin concentration, residual benzoic acid, and flavor differences were explored in WPC80 from whey bleached by the 2 commercially available BP (soluble and insoluble) at 5 mg/kg. In liquid whey, soluble BP bleached more norbixin than insoluble BP, especially at lower concentrations (5 and 10 mg/kg) at both cold (4°C) and hot (50°C) temperatures. The WPC80 from liquid whey bleached with BP at 50°C had lower norbixin concentration, benzoic acid levels, cardboard flavor, and aldehyde levels than WPC80 from liquid whey bleached with BP at 4°C. Regardless of temperature, soluble BP destroyed more norbixin at lower concentrations than insoluble BP. The WPC80 from soluble-BP-bleached wheys had lower cardboard flavor and lower aldehyde levels than WPC80 from insoluble-BP-bleached whey. This study suggests that new, soluble (liquid) BP can be used at lower concentrations than insoluble BP to achieve equivalent bleaching and that less residual benzoic acid remains in WPC80 powder from liquid whey

  5. [8-hydroxy-dihydroberberine ameliorated insulin resistance induced by high FFA and high glucose in 3T3-L1 adipocytes].

    PubMed

    Xu, Li-jun; Lu, Fu-er; Yi, Ping; Wang, Zeng-si; Wei, Shi-chao; Chen, Guang; Dong, Hui; Zou, Xin

    2009-11-01

    The purpose of the study is to investigate the effect of 8-hydroxy-dihydroberberine on insulin resistance induced by high free fatty acid (FFA) and high glucose in 3T3-L1 adipocytes and its possible molecular mechanism. Palmic acid or glucose in combination with insulin was used to induce insulin resistance in 3T3-L1 adipocytes. 8-Hydroxy-dihydroberberine and berberine were added to the cultured medium separately, which were considered as treated group and positive control group. The rate of glucose uptake was determined by 2-deoxy-[3H]-D-glucose method. The amount of glucose consumption in the medium was measured by glucose oxidase method. Cell growth and proliferation of 3T3-L1 adipocytes were detected with Cell Counting Kit-8 (CCK-8) assay. After incubated with palmic acid for 24 hours or glucose with insulin for 18 hours, the rate of glucose transport in 3T3-L1 adipocytes was inhibited by 67% and 58%, respectively. The amount of glucose consumption in 3T3-L1 adipose cells was decreased by 41% after cells were incubated with palmic acid for 24 h. However, the above changes were reversed by pretreatment with 8-hydroxy-dihydroberberine for 24 and 48 h. Significant difference existed between groups. Insulin resistance in 3T3-L1 adipocytes, which is induced by high FFA and high glucose, could be ameliorated by 8-hydroxy-dihydroberberine.

  6. Effect of nitric acid concentrations on synthesis and stability of maghemite nanoparticles suspension.

    PubMed

    Nurdin, Irwan; Johan, Mohd Rafie; Yaacob, Iskandar Idris; Ang, Bee Chin

    2014-01-01

    Maghemite (γ-Fe2O3) nanoparticles have been synthesized using a chemical coprecipitation method at different nitric acid concentrations as an oxidizing agent. Characterization of all samples performed by several techniques including X-ray diffraction (XRD), transmission electron microscopy (TEM), alternating gradient magnetometry (AGM), thermogravimetric analysis (TGA), dynamic light scattering (DLS), and zeta potential. The XRD patterns confirmed that the particles were maghemite. The crystallite size of all samples decreases with the increasing concentration of nitric acid. TEM observation showed that the particles have spherical morphology with narrow particle size distribution. The particles showed superparamagnetic behavior with decreased magnetization values at the increasing concentration of nitric acid. TGA measurement showed that the stability temperature decreases with the increasing concentration of nitric acid. DLS measurement showed that the hydrodynamic particle sizes decrease with the increasing concentration of nitric acid. Zeta potential values show a decrease with the increasing concentration of nitric acid. The increasing concentration of nitric acid in synthesis of maghemite nanoparticles produced smaller size particles, lower magnetization, better thermal stability, and more stable maghemite nanoparticles suspension.

  7. Single-laboratory validation of an LC-MS/MS method for determining florfenicol (FF) and florfenicol amine (FFA) residues in chicken feathers and application to a residue-depletion study.

    PubMed

    Cornejo, J; Pokrant, E; Riquelme, R; Briceño, C; Maddaleno, A; Araya-Jordán, C; San Martin, B

    2017-04-01

    A suitable analytical method is required to study the behaviour of florfenicol (FF) and its metabolite florfenicol amine (FFA) in broiler's feathers. An LC-MS/MS method was developed, assessed and intra-laboratory-validated for FF and FFA analyses. We chose cloramphenicol-d5 as an internal standard, acetone as a solvent for the extraction of the analytes and dichloromethane for the clean-up. Through LC-MS/MS analysis, we established a detection limit of 20 μg kg(-)(1), as well as calculated quantification limits of 24.4 and 24.5 μg kg(-)(1) for FF and FFA, respectively. Validation parameters such as linearity, recovery and precision were calculated following Commission Decision 2002/657/EC. For linearity, all standard curves showed a standard coefficient greater than 0.99. Recoveries ranged from 99% to 102% for all studied concentrations. The results show that this analytical method is precise and reliable. For the depletion study, 64 Ross 308 broilers were treated with a therapeutic dosage of 10% FF during 5 consecutive days and their feathers were then analysed. Samples were drawn on days 5, 10, 15, 20, 25, 30, 35 and 40 post-treatments. As for the control group, 16 broiler chickens were raised under the same regime. Throughout the whole study, the detected concentrations of FF and FFA in feather samples were above 100 µg kg(-)(1). In fact, even on day 30 post-treatment we detected concentrations of 221.8 and 28.8 µg kg(-)(1) for FF and FFA, respectively. Based on these results, we conclude that these analytes will persist for a long time and will deplete slowly in feathers of treated broiler chickens.

  8. High aerosol acidity despite declining atmospheric sulfate concentrations over the past 15 years

    NASA Astrophysics Data System (ADS)

    Weber, Rodney J.; Guo, Hongyu; Russell, Armistead G.; Nenes, Athanasios

    2016-04-01

    Particle acidity affects aerosol concentrations, chemical composition and toxicity. Sulfate is often the main acid component of aerosols, and largely determines the acidity of fine particles under 2.5 μm in diameter, PM2.5. Over the past 15 years, atmospheric sulfate concentrations in the southeastern United States have decreased by 70%, whereas ammonia concentrations have been steady. Similar trends are occurring in many regions globally. Aerosol ammonium nitrate concentrations were assumed to increase to compensate for decreasing sulfate, which would result from increasing neutrality. Here we use observed gas and aerosol composition, humidity, and temperature data collected at a rural southeastern US site in June and July 2013 (ref. ), and a thermodynamic model that predicts pH and the gas-particle equilibrium concentrations of inorganic species from the observations to show that PM2.5 at the site is acidic. pH buffering by partitioning of ammonia between the gas and particle phases produced a relatively constant particle pH of 0-2 throughout the 15 years of decreasing atmospheric sulfate concentrations, and little change in particle ammonium nitrate concentrations. We conclude that the reductions in aerosol acidity widely anticipated from sulfur reductions, and expected acidity-related health and climate benefits, are unlikely to occur until atmospheric sulfate concentrations reach near pre-anthropogenic levels.

  9. Short communication: Association of milk fatty acids with early lactation hyperketonemia and elevated concentration of nonesterified fatty acids.

    PubMed

    Mann, S; Nydam, D V; Lock, A L; Overton, T R; McArt, J A A

    2016-07-01

    The objective of our study was to extend the limited research available on the association between concentrations of milk fatty acids and elevated nonesterified fatty acids (NEFA) and β-hydroxybutyrate (BHB) concentrations in early lactation dairy cattle. Measurement of milk fatty acids for detection of cows in excessive negative energy balance has the potential to be incorporated in routine in-line monitoring systems. Blood samples were taken from 84 cows in second or greater lactation 3 times per week between 3 to 14 d in milk. Cows were characterized as hyperketonemic (HYK) if blood BHB concentration was ≥1.2mmol/L at least once and characterized as having elevated concentrations of NEFA (NEFAH) if serum NEFA concentration was ≥1mmol/L at least once. Composition of colostrum and milk fatty acids at wk 2 postpartum was used to investigate the potential diagnostic value of individual fatty acids and fatty acid ratios for the correct classification of cows with NEFA and BHB concentrations above these thresholds, respectively. Receiver operating characteristic (ROC) curves were used to identify thresholds of fatty acid concentration and fatty acid ratios when ROC area under the curve was ≥0.70. Correct classification rate (CCR, %) was calculated as {[(number of true positives + number of true negatives)/total number tested] × 100}. None of the colostrum fatty acids yielded a sufficiently high area under the curve in ROC analysis for the association with HYK and NEFAH. The following fatty acids and fatty acid ratios were identified for an association with NEFAH (threshold, CCR): C15:0 (≤0.65g/100g, 68.3%); cis-9 C16:1 (≥1.85g/100g, 70.7%); cis-9 C18:1 (≥26g/100g, 69.5%), cis-9 C18:1 to C15:0 ratio (≥45, 69.5%); cis-9 C16:1 to C15:0 (≥2.50, 73.2%). Several fatty acids were associated with HYK (threshold, CCR): C6:0 (≤1.68g/100g, 80.5%), C8:0 (≤0.80g/100g, 80.5%), C10:0 (≤1.6g/100g, 79.3%); C12:0 (≤1.42g/100g, 82.9%); C14:0 (≤6.10g/100g, 84

  10. External concentration of organic acid anions and pH: key independent variables for studying how organic acids inhibit growth of bacteria in mildly acidic foods.

    PubMed

    Carpenter, C E; Broadbent, J R

    2009-01-01

    Although the mechanisms by which organic acids inhibit growth of bacteria in mildly acidic foods are not fully understood, it is clear that intracellular accumulation of anions is a primary contributor to inhibition of bacterial growth. We hypothesize that intracellular accumulation of anions is driven by 2 factors, external anion concentration and external acidity. This hypothesis follows from basic chemistry principles that heretofore have not been fully applied to studies in the field, and it has led us to develop a novel approach for predicting internal anion concentration by controlling the external concentration of anions and pH. This approach overcomes critical flaws in contemporary experimental design that invariably target concentration of either protonated acid or total acid in the growth media thereby leaving anion concentration to vary depending on the pK(a) of the acids involved. Failure to control external concentration of anions has undoubtedly confounded results, and it has likely led to misleading conclusions regarding the antimicrobial action of organic acids. In summary, we advocate an approach for directing internal anion levels by controlling external concentration of anions and pH because it presents an additional opportunity to study the mechanisms by which organic acids inhibit bacterial growth. Knowledge gained from such studies would have important application in the control of important foodborne pathogens such as Listeria monocytogenes, and may also facilitate efforts to promote the survival in foods or beverages of desirable probiotic bacteria.

  11. Relationship between adipic acid concentration and the core symptoms of autism spectrum disorders.

    PubMed

    Puig-Alcaraz, Carmen; Fuentes-Albero, Milagros; Cauli, Omar

    2016-08-30

    Dicarboxylic acids are an important source of information about metabolism and potential physiopathological alterations in children with autism spectrum disorders (ASDs). We measured the concentration between dicarboxylic adipic and suberic acids in children with an ASD and typically-developing (TD) children and analyzed any relationships between the severity of the core symptoms of ASDs and other clinical features (drugs, supplements, drugs, or diet). The core symptoms of autism were evaluated using the DSM-IV criteria, and adipic acid and suberic acid were measured in urine samples. Overall, no increase in the concentration of adipic acid in children with ASDs compared to TD children, however when considering vitamin B supplementation in ASD there were significantly increased level of urinary adipic acid in children with an ASD not taking vitamin B supplementation compared to supplemented children or to TD children. No significant difference were observed in suberic acid. Interestingly, the increase in adipic acid concentration was significantly and indirectly correlated with the severity of the deficit in socialization and communication skills in children with an ASD. Therefore, therapeutic treatments aimed at decreasing adipic acid concentration might not be beneficial for treating the core symptoms of ASDs.

  12. Summary and implications of reported amino acid concentrations in the Murchison meteorite

    NASA Astrophysics Data System (ADS)

    Shock, Everett L.; Schulte, Mitchell D.

    1990-11-01

    A study of literature reports of the concentrations of amino acids in extracts from the Murchison meteorite shows that many of the concentration ratios are constant. There are two possible interpretations of these ratios. One is that they are controlled by the pathways through which the amino acids formed, from which it follows that the amino acids are distributed in the same proportions throughout the meteorite. The other interpretation is that the ratios result from the analytical procedures used to extract the amino acids from the meteorite. These methods rely heavily on high-temperature (100°C) aqueous extraction and subsequent high-temperature acid hydrolysis. A correlation was observed in the present study between the relative concentrations of several amino acids in the meteorite extracts and their relative aqueous solubilities at 100°C (alanine, valine, leucine, isoleucine, norleucine, aspartic acid, glutamic acid, and glycine). The extract solutions are dilute, and far from the saturation limits, but these correlations suggest that the sampling procedure affects directly the reported concentrations for these amino acids. Ratios of the concentration of serine to those of glycine are also constant but cannot be accounted for solely by relative solubilities, and, as suggested elsewhere, serine as well as phenylalanine and methionine may be terrestrial contaminants. Data for β-alanine, α-aminobutyric acid, proline, sarcosine, alloisoleucine, β-aminoisobutyric acid, β-aminobutyric acid, and threonine also show constant abundances relative to glycine, but lack of solubility data at extraction conditions prohibits evaluating the extent of possible sampling bias for these amino acids. If the extraction process does not bias the results, and all extractable amino acids are removed from meteorite samples, then the properties of amino acids which control both their solubilities and their concentrations in the meteorite need to be established. The possibility of

  13. Concentration dependence of 4-methylbenzophenone choleic acid crystal phosphorescence: Evidence for a percolation driven structural transformation

    NASA Astrophysics Data System (ADS)

    Kook, S.-K.; Kim, D.-Y.; Hanson, D. M.

    1989-12-01

    Steady state phosphorescence spectra at 4.2 K were obtained for different concentrations of 4-methylbenzophenone (MBP) doped into deoxycholic acid (DCA) crystals. The spectra indicate that at concentrations of 14% and below, the sample consists of choleic acid crystals partially filled with MBP and as the concentration increases to 16%, enough guest sites are filled with MBP to cause the local structure to change to that of the stoichiometric crystal. The stoichiometric ratio of DCA to MBP was determined to be 2:1. Spectral shifts characteristic of energy transfer processes are not observed over the concentration range of 4% to 33% MBP.

  14. Concentration and fractionation of hydrophobic organic acid constituents from natural waters by liquid chromatography

    USGS Publications Warehouse

    Thurman, E.M.; Malcolm, R.L.

    1979-01-01

    A scheme is presented which used adsorption chromatography with pH gradient elution and size-exclusion chromatography to concentrate and separate hydrophobic organic acids from water. A review of chromatographic processes involved in the flow scheme is also presented. Organic analytes which appear in each aqueous fraction are quantified by dissolved organic carbon analysis. Hydrophobic organic acids in a water sample are concentrated on a porous acrylic resin. These acids usually constitute approximately 30-50 percent of the dissolved organic carbon in an unpolluted water sample and are eluted with an aqueous eluent (dilute base). The concentrate is then passed through a column of polyacryloylmorpholine gel, which separates the acids into high- and low-molecular-weight fractions. The high- and low-molecular-weight eluates are reconcentrated by adsorption chromatography, then are eluted with a pH gradient into strong acids (predominately carboxylic acids) and weak acids (predominately phenolic compounds). For standard compounds and samples of unpolluted waters, the scheme fractionates humic substances into strong and weak acid fractions that are separated from the low molecular weight acids. A new method utilizing conductivity is also presented to estimate the acidic components in the methanol fraction.

  15. Organic Acid Concentrations in Rivers Within the Amazon River Drainage Basin

    NASA Astrophysics Data System (ADS)

    Skoog, A.

    2007-12-01

    The composition of the dissolved organic matter pool in both fresh and marine waters is largely unknown. Concentrations of low-molecular-weight organic acids (oxalate, citrate, glycolate, formate, acetate, succinate) have been determined in Brasilian (18 rivers sampled) and Peruvian (19 rivers sampled) rivers within the Amazon River drainage basin. Succinate concentrations were below the detection limit in all rivers. The dominant acid varied among the sampled rivers, indicating that organic acid concentrations depend on river basin characteristics. Organic-acid carbon comprised a highly significant, but variable, fraction of total dissolved carbon, with a range of 3-90%, indicating that organic-acid-derived carbon may be an important source of biologically labile carbon within the Amazon River drainage basin.

  16. Using Simple Quadratic Equations to Estimate Equilibrium Concentrations of an Acid

    ERIC Educational Resources Information Center

    Brilleslyper, Michael A.

    2004-01-01

    Application of quadratic equations to standard problem in chemistry like finding equilibrium concentrations of ions in an acid solution is explained. This clearly shows that pure mathematical analysis has meaningful applications in other areas as well.

  17. Plasma osmotic and electrolyte concentrations of largemouth bass from some acidic Florida lakes

    SciTech Connect

    Canfield, D.E. Jr.; Maceina, M.J.; Nordlie, F.G.; Shireman, J.V.

    1985-05-01

    Five acidic clear (pH 3.7-4.9), three acidic colored (pH 4.1-4.6), and three neutral (pH 6.9-7.3) north-central Florida lakes were surveyed in 1983 to determine plasma osmotic and electrolyte concentrations, growth, and coefficients of condition for largemouth bass Micropterus salmoides floridanus. Plasma osmotic concentrations averaged greater than 273 milliosmoles/kg in fish from acidic colored and circumneutral lakes, but averaged less than 269 milliosmoles/kg in four of the acidic clear lakes. Growth and coefficients of condition of largemouth bass > 305 mm total length in the acidic lakes were significantly lower than in the neutral lakes. Reductions in fish growth and condition, however, could be related to either acidic conditions or lake trophic status. 29 references, 3 tables.

  18. Effects of chromic-acid concentration on the structure and properties of chromium coatings

    SciTech Connect

    Solodkova, L.N.; Solov'eva, Z.A.; Monev, M.; Nikolova, S.; Rashkov, S.; Dobrev, Ts.

    1987-10-01

    In the interest of decreasing the amount of chromium and other electrolytic effluents that enter the waste stream during chromium electrodeposition processes, and of optimizing plating speeds at reduced chromic acid concentrations, the authors seek to establish the effects of decreasing the chromic acid concentration in the electrolyte on the microstructure, microhardness, internal stress behavior, and tendency toward hydridation of chromium coatings obtained from various electrolyte compositions. Plating kinetics and lattice parameters were also investigated.

  19. Organosulfates and organic acids in Arctic aerosols: speciation, annual variation and concentration levels

    NASA Astrophysics Data System (ADS)

    Hansen, A. M. K.; Kristensen, K.; Nguyen, Q. T.; Zare, A.; Cozzi, F.; Nøjgaard, J. K.; Skov, H.; Brandt, J.; Christensen, J. H.; Ström, J.; Tunved, P.; Krejci, R.; Glasius, M.

    2014-02-01

    Sources, composition and occurrence of secondary organic aerosols (SOA) in the Arctic were investigated at Zeppelin Mountain, Svalbard, and Station Nord, northeast Greenland, during the full annual cycle of 2008 and 2010 respectively. We focused on the speciation of three types of SOA tracers: organic acids, organosulfates and nitrooxy organosulfates from both anthropogenic and biogenic precursors, here presenting organosulfate concentrations and compositions during a full annual cycle and chemical speciation of organosulfates in Arctic aerosols for the first time. Aerosol samples were analysed using High Performance Liquid Chromatography coupled to a quadrupole Time-of-Flight mass spectrometer (HPLC-q-TOF-MS). A total of 11 organic acids (terpenylic acid, benzoic acid, phthalic acid, pinic acid, suberic acid, azelaic acid, adipic acid, pimelic acid, pinonic acid, diaterpenylic acid acetate (DTAA) and 3-methyl-1,2,3-butanetricarboxylic acid (MBTCA)), 12 organosulfates and one nitrooxy organosulfate were identified at the two sites. Six out of the 12 organosulfates are reported for the first time. Concentrations of organosulfates follow a distinct annual pattern at Station Nord, where high concentration were observed in late winter and early spring, with a mean total concentration of 47 (±14) ng m-3, accounting for 7 (±2)% of total organic matter, contrary to a considerably lower organosulfate mean concentration of 2 (±3) ng m-3 (accounting for 1 (±1)% of total organic matter) observed during the rest of the year. The organic acids followed the same temporal trend as the organosulfates at Station Nord; however the variations in organic acid concentrations were less pronounced, with a total mean organic acid concentration of 11.5 (±4) ng m-3 (accounting for 1.7 (±0.6)% of total organic matter) in late winter and early spring, and 2.2 (±1) ng m-3 (accounting for 0.9 (±0.4)% of total organic matter) during the rest of the year. At Zeppelin Mountain

  20. Relationships between Stomatal Behavior and Internal Carbon Dioxide Concentration in Crassulacean Acid Metabolism Plants

    PubMed Central

    Cockburn, William; Ting, Irwin P.; Sternberg, Leonel O.

    1979-01-01

    Measurements of internal gas phase CO2 concentration, stomatal resistance, and acid content were made in Crassulacean acid metabolism plants growing under natural conditions. High CO2 concentrations, sometimes in excess of 2%, were observed during the day in a range of taxonomically widely separated plants (Opuntia ficus-indica L., Opuntia basilaris Engelm. and Bigel., Agave desertii Engelm., Yucca schidigera Roezl. ex Ortiges, Ananas comosus [L.] Merr., Aloe vera L., Cattleya sp. and Phalanopsis sp.) and below ambient air concentrations were observed at night. Stomatal resistance was always high when CO2 concentration was high and experiments in which attempts were made to manipulate internal CO2 concentrations gave data consistent with stomatal behavior in Crassulacean acid metabolism being controlled by internal CO2 concentration. Exogenous CO2 applied in darkness at a concentration similar to those observed in the light caused stomatal resistance to increase. In pads of Opuntia basilaris Engelm. and Bigel. subjected to severe water stress internal gas phase CO2 concentrations exhibited fluctuations opposite in phase to fluctuations in acid content. Stomatal resistance remained high and the opening response to low CO2 concentration was almost entirely eliminated. PMID:16660851

  1. Relationships between Stomatal Behavior and Internal Carbon Dioxide Concentration in Crassulacean Acid Metabolism Plants.

    PubMed

    Cockburn, W

    1979-06-01

    Measurements of internal gas phase CO(2) concentration, stomatal resistance, and acid content were made in Crassulacean acid metabolism plants growing under natural conditions. High CO(2) concentrations, sometimes in excess of 2%, were observed during the day in a range of taxonomically widely separated plants (Opuntia ficus-indica L., Opuntia basilaris Engelm. and Bigel., Agave desertii Engelm., Yucca schidigera Roezl. ex Ortiges, Ananas comosus [L.] Merr., Aloe vera L., Cattleya sp. and Phalanopsis sp.) and below ambient air concentrations were observed at night.Stomatal resistance was always high when CO(2) concentration was high and experiments in which attempts were made to manipulate internal CO(2) concentrations gave data consistent with stomatal behavior in Crassulacean acid metabolism being controlled by internal CO(2) concentration. Exogenous CO(2) applied in darkness at a concentration similar to those observed in the light caused stomatal resistance to increase.In pads of Opuntia basilaris Engelm. and Bigel. subjected to severe water stress internal gas phase CO(2) concentrations exhibited fluctuations opposite in phase to fluctuations in acid content. Stomatal resistance remained high and the opening response to low CO(2) concentration was almost entirely eliminated.

  2. Size-resolved sulfuric acid mist concentrations at phosphate fertilizer manufacturing facilities in Florida.

    PubMed

    Hsu, Yu-Mei; Wu, Chang-Yu; Lundgren, Dale A; Birky, Brian K

    2007-01-01

    Strong inorganic acid mists containing sulfuric acid were identified as a 'known human carcinogen' in a National Toxicology Program (NTP) report where phosphate fertilizer manufacture was listed as one of many occupational exposures to strong acids. To properly assess the occupational exposure to sulfuric acid mists in modern facilities, approved National Institute for Occupational Safety and Health (NIOSH) Method 7903 and a cascade impactor were used for measuring the total sulfuric acid mist concentration and size-resolved sulfuric acid mist concentration, respectively. Sampling was conducted at eight phosphate fertilizer plants and two background sites in Florida and there were 24 sampling sites in these plants. Samples were analyzed by ion chromatography (IC) to quantify the water-soluble ion species. The highest sulfuric acid concentrations by the cascade impactor were obtained at the sulfuric acid pump tank area. When high aerosol mass concentrations (100 micro g m(-3)) were observed at this area, the sulfuric acid mists were in the coarse mode. The geometric mean sulfuric acid concentrations (+/-geometric standard deviation) of PM(23) (aerodynamic cut size smaller than 23 micro m), PM(10) and PM(2.5) from the cascade impactor were 41.7 (+/-5.5), 37.9 (+/-5.8) and 22.1 (+/-4.5) micro g m(-3), respectively. The geometric mean (+/-geometric standard deviation) for total sulfuric acid concentration from the NIOSH method samples was 143 (+/-5.08) micro g m(-3). Sulfuric acid mist concentrations varied significantly among the plants and even at the same location. The measurements by the NIOSH method were 1.5-229 times higher than those by the cascade impactor. Moreover, using the NIOSH method, the sulfuric acid concentrations measured at the lower flow rate (0.30 Lpm) were higher than those at the higher flow rate (0.45 Lpm). One possible reason for the significant differences between the results from the cascade impactor and the NIOSH method is the potential

  3. Physiological Effects of Free Fatty Acid Production in Genetically Engineered Synechococcus elongatus PCC 7942

    PubMed Central

    Ruffing, Anne M.; Jones, Howland D.T.

    2012-01-01

    The direct conversion of carbon dioxide into biofuels by photosynthetic microorganisms is a promising alternative energy solution. In this study, a model cyanobacterium, Synechococcus elongatus PCC 7942, is engineered to produce free fatty acids (FFA), potential biodiesel precursors, via gene knockout of the FFA-recycling acyl-ACP synthetase and expression of a thioesterase for release of the FFA. Similar to previous efforts, the engineered strains produce and excrete FFA, but the yields are too low for large-scale production. While other efforts have applied additional metabolic engineering strategies in an attempt to boost FFA production, we focus on characterizing the engineered strains to identify the physiological effects that limit cell growth and FFA synthesis. The strains engineered for FFA-production show reduced photosynthetic yields, chlorophyll-a degradation, and changes in the cellular localization of the light-harvesting pigments, phycocyanin and allophycocyanin. Possible causes of these physiological effects are also identified. The addition of exogenous linolenic acid, a polyunsaturated FFA, to cultures of S. elongatus 7942 yielded a physiological response similar to that observed in the FFA-producing strains with only one notable difference. In addition, the lipid constituents of the cell and thylakoid membranes in the FFA-producing strains show changes in both the relative amounts of lipid components and the degree of saturation of the fatty acid side chains. These changes in lipid composition may affect membrane integrity and structure, the binding and diffusion of phycobilisomes, and the activity of membrane-bound enzymes including those involved in photosynthesis. Thus, the toxicity of unsaturated FFA and changes in membrane composition may be responsible for the physiological effects observed in FFA-producing S. elongatus 7942. These issues must be addressed to enable the high yields of FFA synthesis necessary for large-scale biofuel

  4. Kinetic study of free fatty acid esterification reaction catalyzed by recoverable and reusable hydrochloric acid.

    PubMed

    Su, Chia-Hung

    2013-02-01

    The catalytic performance and recoverability of several homogeneous acid catalysts (hydrochloric, sulfuric, and nitric acids) for the esterification of enzyme-hydrolyzed free fatty acid (FFA) and methanol were studied. Although all tested catalysts drove the reaction to a high yield, hydrochloric acid was the only catalyst that could be considerably recovered and reused. The kinetics of the esterification reaction catalyzed by hydrochloric acid was investigated under varying catalyst loading (0.1-1M), reaction temperature (303-343K), and methanol/FFA molar ratio (1:1-20:1). In addition, a pseudo-homogeneous kinetic model incorporating the above factors was developed. A good agreement (r(2)=0.98) between the experimental and calculated data was obtained, thus proving the reliability of the model. Furthermore, the reusability of hydrochloric acid in FFA esterification can be predicted by the developed model. The recoverable hydrochloric acid achieved high yields of FFA esterification within five times of reuse.

  5. The triacylglycerol preparation of conjugated linoleic acid reduces lipid oxidation in irradiated, cooked ground beef patties.

    PubMed

    Chae, S H; Keeton, J T; Miller, R K; Johnson, D; Maxim, J; Smith, S B

    2009-04-01

    It is proposed that conjugated linoleic acid (CLA) would depress the lipid oxidation caused by irradiation of cooked, aerobically stored ground beef patties. The free fatty acid (FFA-CLA) and triacylglycerol (TAG-CLA) preparations of CLA were added at 0%, 1%, 2%, or 4% during the grinding process. Patties were irradiated at 1.5-2.0kGy and frozen at -20°C. Subsequently, the patties were tempered to 4°C, cooked to 70°C and held at 4°C for 7d. Enrichment of ground beef with CLA increased the cis-9,trans-11 and CLA trans-10,cis-12 CLA isomers in ground beef patties, even after cooking. Weight loss (P=0.03) and percentage fat (P=0.05) were higher in irradiated beef patties than in control patties. Irradiation decreased the concentration of α-linolenic acid (18:3n-3) in the ground beef by over 60% (P=0.07), whereas thiobarbituric acid reactive substances (TBARS) values were higher (P=0.004) in irradiated beef patties than in control patties. The 1% concentration of added TAG-CLA reduced TBARS in irradiated ground beef patties, whereas 2% and 4% FFA-CLA depressed TBARS (CLA type×percentage interaction P=0.04). Irradiation increased the cardboard and painty aromatic attributes (P⩽0.05), and FFA-CLA preparation increased the painty aromatic attribute and afterburn aftertaste, but these effects were not observed with the TAG-CLA preparation (CLA type×treatment interaction P<0.04). Adding 1% TAG-CLA to ground beef during grinding can reduce lipid oxidation in irradiated, cooked ground beef patties without the negative aftertastes associated with the FFA-CLA preparation.

  6. Determination of Dicarboxylic Acid Concentrations in Surface Microlayer of Dams in Okinawa, Japan

    NASA Astrophysics Data System (ADS)

    Kotani, Y.; Taira, N.; Kamizato, C.; Arakaki, T.

    2008-12-01

    The surface microlayer (SML) is a thin layer that forms the boundary between atmosphere and water body. The SML includes fatty acid, protein and other organic compounds. It is the site across which the atmosphere-water system interacts. It also has unique chemical, physical and biological properties, which are very different from those of the underlying water. We determined concentrations of dicarboxylic acids (oxalic, malic, malonic, succinic, adipic, phthalic, fumaric, and maleic acids) in the SML, and compared with those of underlying bulk water. Dicarboxylic acids are the major organic compounds found in atmospheric aerosols, which can be derived from the wind-blown SML. The sampling sites we chose were dams in Okinawa, Japan. The SML was sampled by using a glass plate method. Concentrations of dicarboxylic acids were determined by using a GC-FID after derivatization. The results showed that the dicarboxylic acid concentrations were 2- 17 times higher than those of the underlying water. We have also found that the concentrations of some of the dicarboxylic acids were lower in the afternoon than those in the morning at the same sampling site.

  7. Concentration of Nitric Acid Strongly Influences Chemical Composition of Graphite Oxide.

    PubMed

    Jankovsky, Ondrej; Novacek, Michal; Luxa, Jan; Sedmidubsky, David; Bohacova, Marie; Pumera, Martin; Sofer, Zdenek

    2017-02-28

    Graphite oxide is the most widely used precursor for the synthesis of graphene by top-down methods. We demonstrate a significant influence of nitric acid concentration on the structure and composition of the graphite oxide prepared by graphite oxidation. In general, two main chlorate based oxidation methods are currently used for graphite oxide synthesis, Staudenmaier method dealing with 98 wt.% nitric acid and Hofmann method dealing with 68 wt.% nitric acid. However a gradual change of nitric acid concentration allowed for the continuous change of the graphite oxide composition. The prepared samples were thoroughly characterized by microscopic techniques as well as various spectroscopic and analytical methods. Lowering of nitric acid concentration led to an increase of oxidation degree and in particular to a concentration of epoxy and hydroxyl groups. This knowledge is not only useful for the large scale synthesis of graphite oxide with tunable size and chemical composition, but the use of nitric acid in lower concentration can also significantly reduce the overall cost of the synthesis.

  8. Hydrolysis optimization and characterization study of preparing fatty acids from Jatropha curcas seed oil

    PubMed Central

    2011-01-01

    Background Fatty acids (FAs) are important as raw materials for the biotechnology industry. Existing methods of FAs production are based on chemical methods. In this study potassium hydroxide (KOH)-catalyzed reactions were utilized to hydrolysis Jatropha curcas seed oil. Results The parameters effect of ethanolic KOH concentration, reaction temperature, and reaction time to free fatty acid (FFA%) were investigated using D-Optimal Design. Characterization of the product has been studied using Fourier transforms infrared spectroscopy (FTIR), gas chromatography (GC) and high performance liquid chromatography (HPLC). The optimum conditions for maximum FFA% were achieved at 1.75M of ethanolic KOH concentration, 65°C of reaction temperature and 2.0 h of reaction time. Conclusions This study showed that ethanolic KOH concentration was significant variable for J. curcas seed oil hydrolysis. In a 18-point experimental design, FFA% of hydrolyzed J. curcas seed oil can be raised from 1.89% to 102.2%, which proved by FTIR and HPLC. PMID:22044685

  9. Comparison of XAD macroporous resins for the concentration of fulvic acid from aqueous solution

    USGS Publications Warehouse

    Aiken, G.R.

    1979-01-01

    Five macroreticular, nonlonlc AmberlHe XAD resins were evaluated for concentration and Isolation of fulvlc acid from aqueous solution. The capacity of each resin for fulvlc acid was measured by both batch and column techniques. Elution efficiencies were determined by desorptlon with 0.1 N NaOH. Highest recoveries were obtained with the acrylic ester resins which proved to be most efficient for both adsorption and elution of fulvlc acid. Compared to the acrylic ester resins, usefulness of the styrene dvlnybenzene resins to remove fulvlc acid is limited because of slow diffusion-controlled adsorption and formation of charge-transfer complexes, which hinders elution. ?? 1979 American Chemical Society.

  10. Effects of squat exercise and branched-chain amino acid supplementation on plasma free amino acid concentrations in young women.

    PubMed

    Shimomura, Yoshiharu; Kobayashi, Hisamine; Mawatari, Kazunori; Akita, Keiichi; Inaguma, Asami; Watanabe, Satoko; Bajotto, Gustavo; Sato, Juichi

    2009-06-01

    The present study was conducted to examine alterations in plasma free amino acid concentrations induced by squat exercise and branched-chain amino acid (BCAA) supplementation in young, untrained female subjects. In the morning on the exercise session day, participants ingested drinks containing either BCAA (isoleucine:leucine:valine=1:2.3:1.2) or dextrin (placebo) at 0.1 g/kg body weight 15 min before a squat exercise session, which consisted of 7 sets of 20 squats, with 3 min intervals between sets. In the placebo trial, plasma BCAA concentrations were decreased subsequent to exercise, whereas they were significantly increased in the BCAA trial until 2 h after exercise. Marked changes in other free amino acids in response to squat exercise and BCAA supplementation were observed. In particular, plasma concentrations of methionine and aromatic amino acids were temporarily decreased in the BCAA trial, being significantly lower than those in the placebo trial. These results suggest that BCAA intake before exercise affects methionine and aromatic amino acid metabolism.

  11. Microarray-based transcriptome of Listeria monocytogenes adapted to sublethal concentrations of acetic acid, lactic acid, and hydrochloric acid.

    PubMed

    Tessema, Girum Tadesse; Møretrø, Trond; Snipen, Lars; Heir, Even; Holck, Askild; Naterstad, Kristine; Axelsson, Lars

    2012-09-01

    Listeria monocytogenes , an important foodborne pathogen, commonly encounters organic acids in food-related environments. The transcriptome of L. monocytogenes L502 was analyzed after adaptation to pH 5 in the presence of acetic acid, lactic acid, or hydrochloric acid (HCl) at 25 °C, representing a condition encountered in mildly acidic ready-to-eat food kept at room temperature. The acid-treated cells were compared with a reference culture with a pH of 6.7 at the time of RNA harvesting. The number of genes and magnitude of transcriptional responses were higher for the organic acids than for HCl. Protein coding genes described for low pH stress, energy transport and metabolism, virulence determinates, and acid tolerance response were commonly regulated in the 3 acid-stressed cultures. Interestingly, the transcriptional levels of histidine and cell wall biosynthetic operons were upregulated, indicating possible universal response against low pH stress in L. monocytogenes. The opuCABCD operon, coding proteins for compatible solutes transport, and the transcriptional regulator sigL were significantly induced in the organic acids, strongly suggesting key roles during organic acid stress. The present study revealed the complex transcriptional responses of L. monocytogenes towards food-related acidulants and opens the roadmap for more specific and in-depth future studies.

  12. Determination of D- and L-alanine concentrations using a pyruvic acid sensor.

    PubMed

    Inaba, Yohei; Hamada-Sato, Naoko; Kobayashi, Takeshi; Imada, Chiaki; Watanabe, Etsuo

    2003-08-01

    The concentrations of D- and L-alanine in bivalves are useful as indicators of environmental pollution. Amino acid oxidase with a low substrate specificity catalyzes the oxidation of various amino acids. Among the various amino acids, pyruvic acid can be generated from alanine only by the catalytic oxidative reaction of this oxidase. Therefore, in this study, the concentrations of D- and L-alanine were determined from the concentration of pyruvic acid, which was determined from the consumption of oxygen based on the oxidative reaction of pyruvate oxidase. From this point of view, there is a very strong possibility that biosensors utilizing enzymes with a low substrate specificity can be developed. The results obtained were as follows. (1) The optimum conditions for the use of pyruvic acid sensor were as follows: temperature of 25 degrees C, pH of 6.8, flow rate of 0.1 ml/min, thiamin diphosphate concentration of 1.5 mM, and injection volume of 50 microl. (2) D-Alanine and L-alanine optimally reacted with D- and L-amino acid oxidase at 30 degrees C, pH 8.2, for 30 min and at 37 degrees C, pH 7.8, for 90 min, respectively. (3) The linear relationships between the concentrations of D- and L-alanine and the output of the sensor were obtained at 3.56-106.8 microg of D-alanine and 5.34-71.3 microg of L-alanine. (4) The concentrations of D- and L-alanine in Meretrix iusoria, Patinopecten yessonsi, and Corbicula leana obtained by the proposed assay were in good agreement with those determined by a conventional method.

  13. Influence of bleaching on flavor of 34% whey protein concentrate and residual benzoic acid concentration in dried whey proteins.

    PubMed

    Listiyani, M A D; Campbell, R E; Miracle, R E; Dean, L O; Drake, M A

    2011-09-01

    Previous studies have shown that bleaching negatively affects the flavor of 70% whey protein concentrate (WPC70), but bleaching effects on lower-protein products have not been established. Benzoyl peroxide (BP), a whey bleaching agent, degrades to benzoic acid (BA) and may elevate BA concentrations in dried whey products. No legal limit exists in the United States for BP use in whey, but international concerns exist. The objectives of this study were to determine the effect of hydrogen peroxide (HP) or BP bleaching on the flavor of 34% WPC (WPC34) and to evaluate residual BA in commercial and experimental WPC bleached with and without BP. Cheddar whey was manufactured in duplicate. Pasteurized fat-separated whey was subjected to hot bleaching with either HP at 500 mg/kg, BP at 50 or 100 mg/kg, or no bleach. Whey was ultrafiltered and spray dried into WPC34. Color [L*(lightness), a* (red-green), and b* (yellow-blue)] measurements and norbixin extractions were conducted to compare bleaching efficacy. Descriptive sensory and instrumental volatile analyses were used to evaluate bleaching effects on flavor. Benzoic acid was extracted from experimental and commercial WPC34 and 80% WPC (WPC80) and quantified by HPLC. The b* value and norbixin concentration of BP-bleached WPC34 were lower than HP-bleached and control WPC34. Hydrogen peroxide-bleached WPC34 displayed higher cardboard flavor and had higher volatile lipid oxidation products than BP-bleached or control WPC34. Benzoyl peroxide-bleached WPC34 had higher BA concentrations than unbleached and HP-bleached WPC34 and BA concentrations were also higher in BP-bleached WPC80 compared with unbleached and HP-bleached WPC80, with smaller differences than those observed in WPC34. Benzoic acid extraction from permeate showed that WPC80 permeate contained more BA than did WPC34 permeate. Benzoyl peroxide is more effective in color removal of whey and results in fewer flavor side effects compared with HP and residual BA is

  14. Body mass index, gestational weight gain and fatty acid concentrations during pregnancy: the Generation R Study.

    PubMed

    Vidakovic, Aleksandra Jelena; Jaddoe, Vincent W V; Gishti, Olta; Felix, Janine F; Williams, Michelle A; Hofman, Albert; Demmelmair, Hans; Koletzko, Berthold; Tiemeier, Henning; Gaillard, Romy

    2015-11-01

    Obesity during pregnancy may be correlated with an adverse nutritional status affecting pregnancy and offspring outcomes. We examined the associations of prepregnancy body mass index and gestational weight gain with plasma fatty acid concentrations in mid-pregnancy. This study was embedded in a population-based prospective cohort study among 5636 women. We obtained prepregnancy body mass index and maximum weight gain during pregnancy by questionnaires. We measured concentrations of saturated fatty acid (SFA), monounsaturated fatty acid (MUFA), n-3 polyunsaturated fatty acid (n-3 PUFA) and n-6 polyunsaturated fatty acid (n-6 PUFA) at a median gestational age of 20.5 (95% range 17.1-24.9) weeks. We used multivariate linear regression models. As compared to normal weight women, obese women had higher total SFA concentrations [difference: 0.10 standard deviation (SD) (95% Confidence Interval (CI) 0, 0.19)] and lower total n-3 PUFA concentrations [difference: - 0.11 SD (95% CI - 0.20, - 0.02)]. As compared to women with sufficient gestational weight gain, those with excessive gestational weight gain had higher SFA concentrations [difference: 0.16 SD (95% CI 0.08, 0.25)], MUFA concentrations [difference: 0.16 SD (95% CI 0.08, 0.24)] and n-6 PUFA concentrations [difference: 0.12 SD (95% CI 0.04, 0.21)]. These results were not materially affected by adjustment for maternal characteristics. Our results suggest that obesity and excessive weight gain during pregnancy are associated with an adverse fatty acids profile. Further studies are needed to assess causality and direction of the observed associations.

  15. Concentrating versus non-concentrating reactors for solar photocatalytic degradation of p-nitrotoluene-o-sulfonic acid.

    PubMed

    Parra, S; Malato, S; Blanco, J; Péringer, P; Pulgari, C

    2001-01-01

    The photocatalytic oxidation of the non-biodegradable p-nitrotoluene-o-sulfonic acid (p-NTS) in homogeneous (photo-Fenton reactions) and heterogeneous (with TiO2) solutions has been studied at a pilot-scale under solar irradiation at the Plataforma Solar de Almeria (PSA). In this study two different reactors were tested: a medium concentrating radiation system (Heliomans, HM) and a non-concentrating radiation system (CPC). Their advantages and disadvantages for p-NTS degradation have been compared and discussed. The degradation rates obtained in the CPC collector are around three times more efficient than in the HM collectors. However, in both systems, 100% of the initial concentration of p-NTS was removed. Kinetic experiments were performed in both systems using TiO2 suspensions. During the photodegradation, the disappearance of p-NTS was followed by HPLC, the mineralization of the solution by the TOC technique, the evolution of NO3-, NO2-, and SO4(2-) concentration by ionic chromatography, the toxicity by the standard Microtox test, and the biodegradability by BOD5 and COD measurements. The obtained results demonstrated the utility of the heterogeneous catalysis (using TiO2 as catalyst) as a pretreatment method that can be followed by a biological process.

  16. Dietary predictors and plasma concentrations of perfluorinated alkyl acids in a Singapore population.

    PubMed

    Liu, Yu; Su, Jin; van Dam, Rob M; Prem, Kiesha; Hoong, Joey Y S; Zou, Li; Lu, Yonghai; Ong, Choon Nam

    2017-03-01

    Perfluorinated alkyl acids (PFAAs), a family of man-made organofluorinated compounds, have drawn much attention due to their ubiquitous existence in the environment and their bioaccumulation potential. Here, we examined the plasma concentrations of thirteen PFAAs in a healthy population (N = 270) in Singapore, and investigated the association between major food groups and plasma PFAA concentrations. We detected eight types of PFAAs in more than 75% of all samples (N = 270), and their median concentrations ranged from 0.05 to 8.34 ng mL(-1). Age- and gender-related differences were observed for the three dominant PFAAs, i.e., perfluorooctanesulfonic acid (PFOS), perfluorohexane sulfonate (PFHxS) and perfluorooctanoate acid (PFOA), with concentrations being higher in men and older adults. Multiple linear regression analyses showed that fish, shellfish, red meat and poultry were associated with increased PFAAs concentrations in plasma, whereas grains and soy products showed inverse associations with PFAAs. Further, significant correlations were observed between various long-chain PFAAs and plasma concentrations of omega-3 fatty acids, suggesting seafood was a significant source of these PFAAs, within this population. Future studies on diet exposure to PFAAs are encouraged to focus more on the effects on diet pattern.

  17. Circadian changes in endogenous concentrations of indole-3-acetic acid, melatonin, serotonin, abscisic acid and jasmonic acid in Characeae (Chara australis Brown)

    PubMed Central

    Beilby, Mary J; Turi, Christina E; Baker, Teesha C; Tymm, Fiona JM; Murch, Susan J

    2015-01-01

    Giant-celled Characeae (Chara australis Brown), grown for 4 months on 12/12 hr day/night cycle and summer/autumn temperatures, exhibited distinct concentration maxima in auxin (indole-3-acetic acid; IAA), melatonin and serotonin about 4 hr after subjective daybreak. These concentration peaks persisted after 3 day pretreatment in continuous darkness: confirming a circadian rhythm, rather than a response to “light on.” The plants pretreated for 3 d in continuous light exhibited several large IAA concentration maxima throughout the 24 hr. The melatonin and serotonin concentrations decreased and were less synchronized with IAA. Chara plants grown on 9/15 hr day/night cycle for 4 months and winter/spring temperatures contained much smaller concentrations of IAA, melatonin and serotonin. The IAA concentration maxima were observed in subjective dark phase. Serotonin concentration peaks were weakly correlated with those of IAA. Melatonin concentration was low and mostly independent of circadian cycle. The “dark” IAA concentration peaks persisted in plants treated for 3 d in the dark. The plants pretreated for 3 d in the light again developed more IAA concentration peaks. In this case the concentration maxima in melatonin and serotonin became more synchronous with those in IAA. The abscisic acid (ABA) and jasmonic acid (JA) concentrations were also measured in plants on winter regime. The ABA concentration did not exhibit circadian pattern, while JA concentration peaks were out of phase with those of IAA. The data are discussed in terms of crosstalk between metabolic pathways. PMID:26382914

  18. Energy and Angle Resolved Uptake of Organic Gases in Concentrated Sulfuric Acid

    NASA Astrophysics Data System (ADS)

    Fiehrer, Kathleen; Nathanson, Gilbert

    1996-03-01

    We have measured the uptake of reactive gases in concentrated (98.8 wtsulfuric acid at 298 K. Our goal is to determine the fraction of gas molecules that dissolve in and react with concentrated sulfuric acid as a function of impact angle, collision energy, and gas molecule basicity (pKBH+). These gases include olefins, alcohols, ethers, aldehydes, and carboxylic acids. We have investigated how scattering and solvation compete at high and low impact energies and at grazing and perpendicular approach directions. We find that the sticking probability decreases slowly with increasing impact energy and with more grazing angle of incidence. However, the sticking probabilities change dramatically with gas functionality and scale monotonically with the molecule's solution phase basicity. Thus, the sticking probability decreases in the order ethanol, dimethyl ether, formic acid, acetaldehyde, and propene.

  19. Stage of harvest and polyunsaturated essential fatty acid concentrations in purslane (Portulaca oleraceae) leaves.

    PubMed

    Palaniswamy, U R; McAvoy, R J; Bible, B B

    2001-07-01

    Purslane is a nutritious vegetable crop rich in the polyunsaturated essential fatty acids (PUEFA) alpha-linolenic acid (LNA) and linoleic acid (LA), which are essential for normal human growth, health promotion, and disease prevention. Total lipids and fatty acid concentrations at three stages of harvest (6-, 10-, and 14-true-leaf stages) were examined in a cultivated variety of purslane (Portulaca oleraceae L. var. sativa). The 14-true-leaf stage of growth was found to be ideal for harvest because at this stage the leaf area, shoot fresh weight, shoot dry weight, and PUEFA concentrations per gram of leaf fresh weight were higher (P < or = 0.05) than at the 6- and 10-true-leaf stages of growth. The LNA to LA ratio was also highest at the 14-true-leaf stage.

  20. The formation of calcium lactate crystals is responsible for concentrated acid whey thickening.

    PubMed

    Mimouni, A; Bouhallab, S; Famelart, M H; Naegele, D; Schuck, P

    2007-01-01

    The use of spray drying for dehydration of acid whey is generally limited by the appearance of uncontrolled thickening and solidifying of the whey mass during the lactose crystallization step. The origin of this physical change is still unknown and probably linked to complex interactions between physical properties and chemical composition of these products. To understand this phenomenon, we simulated the thickening of concentrated acid whey on a laboratory scale by measuring the flow resistance changes as a function of time and whey composition. The thickening process was characterized by an amplitude of torque and a lag time (induction time). Thickening of lactic acid whey concentrate occurred regardless of the presence of whey proteins or lactose crystals. Moreover, this work clearly demonstrated that the thickening process was due to the formation of filamentous structures corresponding to calcium lactate crystals and showed a large dependence on calcium and lactate contents, pH, and phosphate concentration.

  1. Platelet-derived Factor Concentrates with Hyaluronic Acid Scaffolds for Treatment of Deep Burn Wounds

    PubMed Central

    Minabe, Toshiharu; Yamakawa, Tomomi; Araki, Jun; Sano, Hitomi; Yoshimura, Kotaro

    2016-01-01

    Summary: A deep burn wound is a critical condition that generally necessitates vascularized tissue coverage. We performed the injection of platelet-derived factor concentrates combined with non–cross-linked hyaluronic acid scaffolds for 2 patients with critical burn wounds with bone and tendon exposure and achieved successful healing. Hyaluronic acid was considered to have served as a controlled-release carrier of platelet-derived factors, being clinically effective for the treatment of deep burn wounds. PMID:27826482

  2. Influence of various concentrations of selenic acid (IV) on the activity of soil enzymes.

    PubMed

    Nowak, J; Kaklewski, K; Klódka, D

    2002-05-27

    The aim of this experiment was the assessment of the influence of various concentrations of H2SeO3 (0.05, 0.5 and 5 mM) on the activity of soil enzymes over 112 days. The lab experiment was performed using soil samples (dust-silt black soil of 1.92% organic C content, pH 7.7), 60% maximal water capacity. The soil samples were treated with a selenic acid water solution at the concentrations mentioned above. As a reference, natural soil was used (without the selenic acid). The activity of the following enzymes was tested: beta-glucosidase, nitrate reductase, urease, dehydrogenase, acid and alkaline phosphatases. The soil was sampled at days 0, 1, 3, 7, 14, 28, 56 and 112. The results of the study have shown that the selenic acid had no effect on the activity of the beta-glucosidase in soil. In the course of the whole experiment, the applied selenic acid inhibited activity of the nitrate reductase up to 70% at 5 mM, and the activity of dehydrogenase was also decreased--by up to 85% at 5 mM, similarly to urease (with the exception of days 14 and 28), and acid phosphatase (until day 56). The activity of alkaline phosphatase was increased by the lowest concentration of selenic acid and decreased by the highest, which was found in the course of the whole experiment. The 5-mM concentration of selenic acid inhibited the activity of all the enzymes tested in this experiment.

  3. The impact of chronic imipramine treatment on amino acid concentrations in the hippocampus of mice.

    PubMed

    Nagasawa, Mao; Murakami, Tatsuro; Tomonaga, Shozo; Furuse, Mitsuhiro

    2012-09-01

    The relationship between antidepressants and monoamine concentrations in the brain has been well investigated, but few studies have investigated the relationship between antidepressants and amino acid concentrations in the brain. The purpose of the present study was therefore to investigate the effect of the chronic antidepressant imipramine on amino acid and monoamine concentrations in the mouse brain and plasma. Chronic imipramine treatment decreased the concentration of 5-hydroxyindoleaceticacid/5-hydroxytryptamine in the cerebral cortex and increased that of norepinephrine (NE) in the hippocampus. Since these changes were conspicuous effects of the antidepressant, we concluded that imipramine acts on the central nervous system. No change in amino acid concentrations in plasma was induced by chronic imipramine treatment, but several changes were confirmed in the cerebral cortex, the hypothalamus and the hippocampus. Chronic imipramine treatment caused increases in L-methionine, L-tyrosine, and L-lysine in the cerebral cortex, and an increase in L-aspartate in the hypothalamus. Contrary to this, the concentrations of L-aspartate, L-serine, L-asparagine, glycine, L-glutamine, gamma-aminobutyric acid, L-threonine, L-arginine, L-proline, L-valine, and L-methionine in the hippocampus were decreased by chronic imipramine treatment. The present results demonstrate that the metabolism of several amino acids in the brain, but not of those in plasma, was altered by chronic imipramine treatment. The findings in the present study may help to further elucidate the relationship between amino acids and the effects and side effects of antidepressants.

  4. Threshold changes in rat brain docosahexaenoic acid incorporation and concentration following graded reductions in dietary alpha-linolenic acid

    PubMed Central

    Taha, Ameer Y.; Chang, Lisa; Chen, Mei

    2016-01-01

    Background This study tested the dietary level of alpha-linolenic acid (α-LNA, 18:3n-3) sufficient to maintain brain 14C-Docosahexaenoic acid (DHA, 22:6n-3) metabolism and concentration following graded α-LNA reduction. Methods 18–21 day male Fischer-344 (CDF) rats were randomized to the AIN-93G diet containing as a % of total fatty acids, 4.6% (“n-3 adequate”), 3.6%, 2.7%, 0.9% or 0.2% (“n-3 deficient”) α-LNA for 15 weeks. Rats were intravenously infused with 14C-DHA to steady state for 5 minutes, serial blood samples collected to obtain plasma and brains excised following microwave fixation. Labeled and unlabeled DHA concentrations were measured in plasma and brain to calculate the incorporation coefficient, k*, and incorporation rate, Jin. Results Compared to 4.6% α-LNA controls, k* was significantly increased in ethanolamine glycerophospholipids in the 0.2% α-LNA group. Circulating unesterified DHA and brain incorporation rates (Jin) were significantly reduced at 0.2% α-LNA. Brain total lipid and phospholipid DHA concentrations were reduced at or below 0.9% α-LNA. Conclusion Threshold changes for brain DHA metabolism and concentration were maintained at or below 0.9% dietary α-LNA, suggesting the presence of homeostatic mechanisms to maintain brain DHA metabolism when dietary α-LNA intake is low. PMID:26869088

  5. Effects of rice harvest moisture on kernel damage and milled rice surface free fatty acid levels.

    PubMed

    Parker, Amanda M; Proctor, Andrew; Eason, Robert L; Jain, Vishal

    2007-01-01

    Surface free fatty acid (FFA) on milled rice is a key factor in determining rice quality and acceptability to the brewing industry. Rice FFA oxidizes, causing off-flavors and odors to develop, compromising the brewing quality of milled rice. The effect of harvest moisture (13%, 16%, and 20%), harvester type (1688 Case and 9500 John Deere), and rice variety (Cocodrie and Bengal) on harvest damaged rough rice and milled rice surface FFA after drying to 12% moisture and 6 mo rough rice storage was examined. The Case harvester produced more damaged kernels than the John Deere harvester, but this was not reflected in surface FFA development. There were no significant FFA differences in variety or harvester type. Rice harvested at a higher moisture content (20%) produced significantly greater FFA values, with a peak near 0.1%, than rice harvested at lower moisture contents (13% and 16%), which had FFA values near 0.08%. Retention of bran by damaged kernels at high harvest moisture probably was responsible for promoting surface FFA development, but if bran was lost at lower harvest moistures, surface FFA, development was limited. Harvest moisture affected milled rice FFA, although rough rice was dried to 12% immediately after harvesting.

  6. Changes in plasma amino acid concentrations with increasing age in patients with propionic acidemia.

    PubMed

    Scholl-Bürgi, Sabine; Sass, Jörn Oliver; Heinz-Erian, Peter; Amann, Edda; Haberlandt, Edda; Albrecht, Ursula; Ertl, Claudia; Sigl, Sara Baumgartner; Lagler, Florian; Rostasy, Kevin; Karall, Daniela

    2010-05-01

    The objective of the study is to analyze plasma amino acid concentrations in propionic acidemia (PA) for the purpose of elucidating possible correlations between propionyl-CoA carboxylase deficiency and distinct amino acid behavior. Plasma concentrations of 19 amino acids were measured in 240 random samples from 11 patients (6 families) with enzymatically and/or genetically proven propionic acidemia (sampling period, January 2001-December 2007). They were compared with reference values from the literature and correlated with age using the Pearson correlation coefficient test. Decreased plasma concentrations were observed for glutamine, histidine, threonine, valine, isoleucine, leucine, phenylalanine and arginine. Levels of glycine, alanine and aspartate were elevated, while values of serine, asparagine, ornithine and glutamate were normal. For lysine, proline and methionine a clear association was not possible. Significant correlations with age were observed for 13 amino acids (positive correlation: asparagine, glutamine, proline, alanine, histidine, threonine, methionine, arginine; negative correlation: leucine, phenylalanine, ornithine, glutamate and aspartate). This study gives new insight over long-term changes in plasma amino acid concentrations and may provide options for future therapies (e.g., substitution of anaplerotic substances) in PA patients.

  7. [Evaluation of folate substitution in women with epilepsy. Determination of erythrocyte folic acid concentrations].

    PubMed

    Bauer, J; Bös, M; Rück, J; Stoffel-Wagner, B

    2011-04-01

    Insufficient maternal folate concentrations appear to be a fetal risk factor for neural tube defects (NTD). Erythrocyte folate concentrations are widely accepted as an indicator of tissue folate storage. We retrospectively evaluated erythrocyte folate concentrations to examine if a recommended daily dosage of 5 mg folic acid is sufficient to balance the impact of antiepileptic drugs (AED) on folate metabolism in women with epilepsy. Data of 48 women (mean age 30.3 years) with idiopathic epilepsy with generalized seizures (n=12) or symptomatic epilepsy with focal seizures (n=36) were available, 43 women submitted to further analysis and 30 women received AED monotherapy. Duration of folic acid supplementation varied between 0.5 and 12 months. The daily dosage of folic acid ranged from 0.4 to 15 mg and 32 women received 5 mg/day. Erythrocyte folate concentrations ranged from 282 to 1596 ng/ml (mean 780 ng/ml). In 29 out of the 32 women (90.6%) on 5 mg folic acid per day, red cell folate was ≥400 ng/ml. In previous studies the risk for NTD was estimated to be 0.8‰ if red cell folate was ≥400 ng/ml. Our results suggest that 5 mg/day folic acid as preconception supplementation in women with epilepsy is effective to balance the impact of AEDs on folate metabolism in women with epilepsy.

  8. Low auxotrophy-complementing amino acid concentrations reduce yeast chronological life span.

    PubMed

    Gomes, Pedro; Sampaio-Marques, Belém; Ludovico, Paula; Rodrigues, Fernando; Leão, Cecília

    2007-01-01

    In the yeast Saccharomyces cerevisiae, interventions resembling caloric restriction, either by reduction of glucose or non-essential amino acid content in the medium, prolong life span and retard aging. Here we have examined the role of auxotrophy-complementing amino acid supplementation of S. cerevisiae strains in determining yeast chronological life span and stress resistance. The results obtained from cells cultured in standard amino acid concentrations revealed a reduced final biomass yield and premature aging phenotypes. These included shorter life span and indicators of oxidative stress, together with a G2/M cell cycle arrest and the appearance of a sub-G0/G1 population pointing to the occurrence of a specific cell death programme under starvation of essential amino acids. In order to overcome this starvation, five times higher amino acid concentrations were supplied to the medium as has already been commonly used by few laboratories. Such cultures reached more than five-fold higher final biomass yield in stationary phase and the early aging phenotypes were abrogated. Furthermore, in a long-lived yeast strain lacking TOR1, there was no positive effect of amino acid supplementation on longevity. On the contrary, amino acid supply had a positive effect on chronological life span of RAS2 deleted cells. This study may provide novel insights into the role of essential nutrients and their effect on aging process and raises the warning that the positive effects of caloric restriction on life span maybe restricted to non-essential nutrients. Moreover, the severe consequences on cell physiology, life span and stress resistance induced by essential amino acid imbalances presents a note of caution for those still using standard amino acid concentrations for studies with auxotrophic yeast strains.

  9. Influence of volatile fatty acid concentration stability on anaerobic degradation of linear alkylbenzene sulfonate.

    PubMed

    Okada, Dagoberto Y; Delforno, Tiago P; Esteves, Andressa S; Polizel, Juliana; Hirasawa, Julia S; Duarte, Iolanda C S; Varesche, Maria B A

    2013-10-15

    Linear alkylbenzene sulfonate (LAS) is an anionic surfactant used in cleaning products, which is usually found in wastewaters. Despite the greater LAS removal rate related to a lower concentrations of volatile fatty acids (VFA), the influence of different ranges of VFA on LAS degradation is not known. LAS degradation was evaluated in upflow anaerobic sludge blanket (UASB) and expanded granular sludge bed (EGSB) reactors at different ranges of VFA concentrations. The reactors were fed with a synthetic wastewater containing LAS (14 mg/L). A greater LAS removal rate (40-80%) was related to the lower and narrower range of acetic acid concentration (1-22 mg/L) in the EGSB reactor. In the UASB reactor, the acetic acid concentrations presented a wider range (2-45 mg/L), and some low LAS removal rates (around 20-25%) were observed even at low acetic acid concentrations (<10 mg/L). The high recirculation rate in the EGSB reactor improved substrate-biomass contact, which resulted in a narrower range of VFA and greater LAS removal rate.

  10. Profile of organic acid concentrations in the digestive gland and hemolymph of Biomphalaria glabrata under estivation.

    PubMed

    Bezerra, J C; Kemper, A; Becker, W

    1999-01-01

    Using high performance liquid chromatography (HPLC) analysis it was possible to determine simultaneously the concentration of organic acids (pyruvate, lactate, succinate, fumarate, malate, acetate, propionate, acetoacetate, and ss-hydroxybutyrate) in the digestive gland and the extracellular concentration of these same acids in the hemolymph of estivating Biomphalaria glabrata, the intermediate host of Schistosoma mansoni. After a 7 day period of estivation, there was a significant increase in the tissue levels of lactate, succinate, malate and acetate compared to non-estivating snails. After 14 days of estivation, the levels of lactate and acetate were also significantly elevated. The hemolymph concentrations of pyruvate and acetate increased significantly after 7 days and acetate concentrations continued to be significantly increased up to 14 days of estivation. The other organic acids studied, such as ketone body acetoacetate and ss-hydroxybutyrate or the volatile acid propionate, did not accumulate. Their tissue concentrations, however, increased on the 7th day of estivation and reached normal levels within two weeks of estivation for some of them. One should take into consideration how the reduction in metabolism can be handled under aerobic conditions, and what role anaerobic pathways may play in both energy formation and redox balance processes.

  11. Regional trends in soil acidification and exchangeable metal concentrations in relation to acid deposition rates.

    PubMed

    Stevens, Carly J; Dise, Nancy B; Gowing, David J

    2009-01-01

    The deposition of high levels of reactive nitrogen (N) and sulphur (S), or the legacy of that deposition, remain among the world's most important environmental problems. Although regional impacts of acid deposition in aquatic ecosystems have been well documented, quantitative evidence of wide-scale impacts on terrestrial ecosystems is not common. In this study we analysed surface and subsoil chemistry of 68 acid grassland sites across the UK along a gradient of acid deposition, and statistically related the concentrations of exchangeable soil metals (1 M KCl extraction) to a range of potential drivers. The deposition of N, S or acid deposition was the primary correlate for 8 of 13 exchangeable metals measured in the topsoil and 5 of 14 exchangeable metals in the subsoil. In particular, exchangeable aluminium and lead both show increased levels above a soil pH threshold of about 4.5, strongly related to the deposition flux of acid compounds.

  12. Effects of Fungicide Treatment on Free Amino Acid Concentration and Acrylamide-Forming Potential in Wheat.

    PubMed

    Curtis, Tanya Y; Powers, Stephen J; Halford, Nigel G

    2016-12-28

    Acrylamide forms from free asparagine and reducing sugars during frying, baking, roasting, or high-temperature processing, and cereal products are major contributors to dietary acrylamide intake. Free asparagine concentration is the determining factor for acrylamide-forming potential in cereals, and this study investigated the effect of fungicide application on free asparagine accumulation in wheat grain. Free amino acid concentrations were measured in flour from 47 varieties of wheat grown in a field trial in 2011-2012. The wheat had been supplied with nitrogen and sulfur and treated with growth regulators and fungicides. Acrylamide formation was measured after the flour had been heated at 180 °C for 20 min. Flour was also analyzed from 24 (of the 47) varieties grown in adjacent plots that were treated in identical fashion except that no fungicide was applied, resulting in visible infection by Septoria tritici, yellow rust, and brown rust. Free asparagine concentration in the fungicide-treated wheat ranged from 1.596 to 3.987 mmol kg(-1), with a significant (p < 0.001 to p = 0.006, F test) effect of variety for not only free asparagine but all of the free amino acids apart from cysteine and ornithine. There was also a significant (p < 0.001, F test) effect of variety on acrylamide formation, which ranged from 134 to 992 μg kg(-1). There was a significant (p < 0.001, F test) correlation between free asparagine concentration and acrylamide formation. Both free asparagine concentration and acrylamide formation increased in response to a lack of fungicide treatment, the increases in acrylamide ranging from 2.7 to 370%. Free aspartic acid concentration also increased, whereas free glutamic acid concentration increased in some varieties but decreased in others, and free proline concentration decreased. The study showed disease control by fungicide application to be an important crop management measure for mitigating the problem of acrylamide formation in wheat

  13. Effect of folic acid supplementation on homocysteine concentration and association with training in handball players

    PubMed Central

    2013-01-01

    Background Strenuous physical activity can alter the status of folic acid, a vitamin directly associated with homocysteine (Hcy); alterations in this nutrient are a risk factor for cardiovascular disease. Handball players are a population at risk for nutrient deficiency because of poor dietary habits. Objective The aims of this study were to evaluate nutritional status for macronutrients and folic acid in members of a high-performance handball team, and determine the effect of a nutritional intervention with folic acid supplementation and education. Design A total of 14 high-performance handball players were monitored by recording training time, training intensity (according to three levels of residual heart rate (RHR): <60%, 60%–80% and >80%), and subjective perceived exertion (RPE) during a 4-month training period. Nutritional, laboratory and physical activity variables were recorded at baseline (Week 0), after 2 months of dietary supplementation with 200 μg folic acid (50% of the recommended daily allowance) (Week 8) and after 2 months without supplementation (Week 16). We compared training load and analyzed changes in plasma concentrations of Hcy before and after the intervention. Results Bivariate analysis showed a significant negative correlation (P < 0.01) between Hcy and folic acid concentrations (r = −0.84) at Week 8, reflecting a significant change in Hcy concentration (P < 0.05) as a result of hyperhomocysteinemia following the accumulation of high training loads. At Week 16 we observed a significant negative correlation (P < 0.01) between Hcy concentration and training time with an RHR <60%, indicating that aerobic exercise avoided abrupt changes in Hcy and may thus reduce the risk of cardiovascular accidents in high-performance athletes. Conclusion Integral monitoring and education are needed for practitioners of handball sports to record their folic acid status, a factor that directly affects Hcy metabolism. Folic acid

  14. Salicylic acid induces apoptosis in colon carcinoma cells grown in-vitro: Influence of oxygen and salicylic acid concentration

    SciTech Connect

    Zitta, Karina; Meybohm, Patrick; Bein, Berthold; Huang, Ying; Heinrich, Christin; Scholz, Jens; Steinfath, Markus; Albrecht, Martin

    2012-04-15

    In solid tumors the hypoxic environment can promote tumor progression and resistance to therapy. Recently, acetylsalicylic acid a major component of analgesic drugs and its metabolite salicylic acid (SA) have been shown to reduce the risk of colon cancer, but the mechanisms of action remain still unclear. Here we elucidate the effects of physiologically relevant concentrations of SA on colon carcinoma cells (CaCo-2) grown under normoxic and hypoxic conditions. Western blotting, caspase-3/7 apoptosis assays, MTS cell-proliferation assays, LDH cytotoxicity assays and hydrogen peroxide measurements were performed to investigate the effects of 1 and 10 {mu}M SA on CaCo-2 cells grown under normoxic conditions and cells exposed to hypoxia. Under normoxic conditions, SA did not influence cell proliferation or LDH release of CaCo-2 cells. However, caspase-3/7 activity was significantly increased. Under hypoxia, cell proliferation was reduced and LDH release and caspase-3/7 activities were increased. None of these parameters was altered by the addition of SA under hypoxic conditions. Hypoxia increased hydrogen peroxide concentrations 300-fold and SA significantly augmented the release of hydrogen peroxide under normoxic, but not under hypoxic conditions. Phosphorylation of the pro-survival kinases akt and erk1/2 was not changed by SA under hypoxic conditions, whereas under normoxia SA reduced phosphorylation of erk1/2 after 2 hours. We conclude that in colon carcinoma cells effects of SA on apoptosis and cellular signaling are dependent on the availability of oxygen. -- Highlights: Black-Right-Pointing-Pointer Effects of salicylic acid on colon carcinoma cells grown under normoxic and hypoxic conditions Black-Right-Pointing-Pointer Salicylic acid increases caspase-3/7 activity and hydrogen peroxide release under normoxia Black-Right-Pointing-Pointer Salicylic acid decreases pro-survival erk-1/2 phosphorylation under normoxia Black-Right-Pointing-Pointer Salicylic acid does

  15. Acid and organic aerosol coatings on magnetic nanoparticles increase iron concentrations in human airway epithelial cells.

    PubMed

    Ghio, Andrew J; Dailey, Lisa A; Richards, Judy H; Jang, Myoseon

    2009-07-01

    Numerous industrial applications for man-made nanoparticles have been proposed. Interactions of nanoparticles with agents in the atmosphere may impact human health. We tested the postulate that in vitro exposures of respiratory epithelial cells to airborne magnetic nanoparticles (MNP; Fe(3)O(4)) with and without a secondary organic aerosol (SOA) and an inorganic acid could affect iron homeostasis, oxidative stress, and interleukin (IL)-8 release. Cell iron concentrations were increased after exposures to MNP and values were further elevated with co-exposures to either SOA or inorganic acid. Increased expression of ferritin and elevated levels of RNA for DMT1, proteins for iron storage and transport respectively, followed MNP exposures, but values were significant for only those with co-exposures to inorganic acid and organic aerosols. Cell iron concentration corresponded to a measure of oxidative stress in the airway epithelial cells; MNP with co-exposures to SOA and inorganic acid increased both available metal and indices of oxidant generation. Finally, the release of a proinflammatory cytokine (i.e. IL-8) by the exposed cells similarly increased with cell iron concentration. We conclude that MNP can interact with a SOA and an inorganic acid to present metal in a catalytically reactive state to cultured respiratory cells. This produces an oxidative stress to affect a release of IL-8.

  16. Production of fuel ethanol from bamboo by concentrated sulfuric acid hydrolysis followed by continuous ethanol fermentation.

    PubMed

    Sun, Zhao-Yong; Tang, Yue-Qin; Iwanaga, Tomohiro; Sho, Tomohiro; Kida, Kenji

    2011-12-01

    An efficient process for the production of fuel ethanol from bamboo that consisted of hydrolysis with concentrated sulfuric acid, removal of color compounds, separation of acid and sugar, hydrolysis of oligosaccharides and subsequent continuous ethanol fermentation was developed. The highest sugar recovery efficiency was 81.6% when concentrated sulfuric acid hydrolysis was carried out under the optimum conditions. Continuous separation of acid from the saccharified liquid after removal of color compounds with activated carbon was conducted using an improved simulated moving bed (ISMB) system, and 98.4% of sugar and 90.5% of acid were recovered. After oligosaccharide hydrolysis and pH adjustment, the unsterilized saccharified liquid was subjected to continuous ethanol fermentation using Saccharomycescerevisiae strain KF-7. The ethanol concentration, the fermentation yield based on glucose and the ethanol productivity were approximately 27.2 g/l, 92.0% and 8.2 g/l/h, respectively. These results suggest that the process is effective for production of fuel ethanol from bamboo.

  17. NHI-Acid Concentration Membranes -- Membrane Recommendations for the S-I Cycle

    SciTech Connect

    Frederick F Stewart

    2007-03-01

    Scope: The purpose of this draft report is to make recommendations concerning the applicability of specific membrane materials for acid concentration processes to the Sulfur-Iodine (S-I) thermochemical cycle integrated laboratory scale (ILS) demonstration. Introduction Acid concentration membrane processes have been studied for possible inclusion in the Sulfur-Iodine integrated laboratory scale (S-I ILS) demonstration. The need for this technology is driven by the chemical processes required for economical water splitting using the S-I cycle. Of the chemical processes inherent to the S-I cycle that have been identified as targets for deployment of membrane technology, three have been studied during the past three fiscal years as a part of the DOE Nuclear Hydrogen Initiative. First, the ability to concentrate hydriodic acid (HI) and iodine mixtures was sought as a method for aiding in the isolation of HI away from water and iodine. Isolated HI would then be delivered to the HI decomposition process for liberation of product hydrogen. Second, an extension of this technology to sulfuric acid was proposed to benefit sulfuric acid decomposition recycle. Third, decomposition of HI to form hydrogen is equilibrium limited. Removal of hydrogen, utilizing Le Chatelier’s principle, will increase to overall conversion and thus increasing the efficiency of the S-I cycle.

  18. Biofilter for generation of concentrated sulphuric acid from H2S.

    PubMed

    Rabbani, K A; Charles, W; Kayaalp, A; Cord-Ruwisch, R; Ho, G

    2016-08-01

    Biofilters are used for the conversion of odorous hydrogen sulphide to odourless sulphate in wastewater treatment plants under the right conditions of moisture and pH. One of the consequences of maintaining the suitable pH and moisture content is the production of large volumes of weakly acidic leachate. This paper presents a biofilter with a maximum H2S elimination capacity of 16.3 g m(-3) h(-1) and removal efficiency greater than 95 % which produces small volumes (1 mL of solution L(-1) of reactor day(-1)) of sulphuric acid with a concentration greater than 5.5 M after 150 days of continuous operation. The concentrated sulphuric acid was produced by intermittently trickling a minimum amount of nutrient solution down the upflow biofilter which created a moisture and pH gradient within the biofilter resulting in an environment at the top for the bacterial conversion of H2S, while sulphuric acid was accumulated at the base. Genetic diversity profiling of samples taken from different sections of the biofilter confirms that the upper sections of the biofilter had the best environment for the bacteria to convert H2S to sulphate. The formation of concentrated sulphuric acid presents an opportunity for the recovery of sulphur from the waste stream as a usable product.

  19. Effect of sulfuric acid concentration of bentonite and calcination time of pillared bentonite

    NASA Astrophysics Data System (ADS)

    Mara, Ady; Wijaya, Karna; Trisunaryati, Wega; Mudasir

    2016-04-01

    An activation of natural clay has been developed. Activation was applied by refluxing the natural bentonite in variation of the sulfuric acid concentration and calcination time of pillared bentonite (PLC). Calcination was applied using oven in microwave 2,45 GHz. Determination of acidity was applied by measuring the amount of adsorbed ammonia and pyridine. Morphological, functional groups and chrystanility characterizations were analyzed using SEM, TEM, FTIR and XRD. Porosity was analyzed using SSA. The results showed that the greater of the concentration of sulfuric acid and calcination time was, the greater the acidity of bentonite as well as the pore diameter were. FTIR spectra showed no fundamental changes in the structure of the natural bentonite, SEM, and TEM images were showing an increase in space or field due to pillarization while the XRD patterns showed a shift to a lower peak. Optimization was obtained at a concentration of 2 M of sulfuric acid and calcination time of 20 minutes, keggin ion of 2.2 and suspension of 10 mmol, respectively each amounted to 11.7490 mmol/gram of ammonia and 2.4437 mmol/gram of pyridine with 154.6391 m2/gram for surface area, 0.130470 m3/gram of pore volume and 3.37484 nm of pore diameter.

  20. Abscisic acid form, concentration, and application timing influence phenology and bud cold hardiness in Merlot grapevines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of abscisic acid (ABA) form, concentration and application timing on bud cold hardiness, phenology and fruiting performance on ‘Merlot’ grapevines (Vitis vinifera) were evaluated in a three year field trial with site locations in British Columbia Canada, Ontario Canada, Washington U.S. ...

  1. Total volatile fatty acid concentrations are unreliable estimators of treatment effects on ruminal fermentation in vivo

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Volatile fatty acid concentrations ([VFA], mM) have long been used to assess impact of dietary treatments on ruminal fermentation in vivo. However, discrepancies in statistical results between VFA and VFA pool size (VFAmol), possibly related to ruminal digesta liquid amount (LIQ, kg), suggest issues...

  2. Stability-time profile of trichloroacetic acid at various concentrations and storage conditions.

    PubMed

    Spinowitz, A L; Rumsfield, J

    1989-09-01

    Trichloroacetic acid (TCA) is a deliquescent chemical widely used for a variety of procedures. Stability of various concentrations of TCA in both amber glass and plastic bottles stored under refrigeration and at room temperature was measured at several time points. Extended stability data suggest that TCA potency is stable for 23 weeks and would best be maintained in glass amber bottles stored under refrigeration.

  3. Effect of manganese on the concentration of amino acids in different regions of the rat brain.

    PubMed

    Lipe, G W; Duhart, H; Newport, G D; Slikker, W; Ali, S F

    1999-01-01

    The present study was designed to determine if chronic exposure of weanlings and adult rats to Mn produces significant alterations in amino acid concentrations in different regions of the rat brain. Weanling (30 day old) and adult (90 day old) male rats were exposed to 10 and 20 mg Mn/kg body weight per day, by gavage, for 30 days. Forty-eight hours after the last dose, animals were sacrificed by decapitation and brains were dissected into different regions to determine the concentration of amino acids by HPLC/EC. A dose dependent decrease in body weight gain was found in the adult, but not in the weanling rats. Significant increases occurred in concentrations of aspartate, glutamate, glutamine, taurine and gamma-aminobutyric acid (GABA) in the cerebellum of the adult rats dosed with 20 mg/kg per day, Mn. A significant decrease in the concentration of glutamine was observed in caudate nucleus and hippocampus of weanling rats dosed with 10 mg/kg, Mn. These data suggest that chronic Mn exposure can produce a decrease in body weight gain in adult rats and alterations in amino acids in different regions of weanling and adult rat brains.

  4. EFFECTS OF THREE CONCENTRATIONS OF MIXED FATTY ACIDS ON DECHLORINATION OF TETRACHLOROETHENE IN AQUIFER MICRO- COSMS

    EPA Science Inventory

    Chloroethenes are among the most common organic contaminants of ground water. The biotransformation of these compounds by reductive dechlorination is a promising technology for in situ treatment. The effects of three concentrations of a fatty acids mixture on the reductive dehalo...

  5. Mineral, flavonoid, and fatty acid concentrations in ten diverse Lablab purpureus (L.) sweet accessions.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seeds of Hyacinth bean (Lablab purpureus [L.]) Sweet containing high concentrations of minerals, flavonoids and fatty acids may provide government agencies with a nutrient-dense and health-beneficial food for use in hunger stricken and nutrient deprived people. Seeds from ten hyacinth bean accession...

  6. Role of lauric acid-potassium hydroxide concentration on bacterial contamination of spray washed broiler carcasses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A series of experiments were conducted to examine reductions in bacterial contamination of broiler carcasses washed in a spray cabinet with various concentrations of lauric acid (LA)-potassium hydroxide (KOH) solutions. Fifty eviscerated carcasses and 5 ceca were obtained from the processing line of...

  7. Dietary n-6 PUFA deprivation for 15 weeks reduces arachidonic acid concentrations while increasing n-3 PUFA concentrations in organs of post-weaning male rats

    PubMed Central

    Igarashi, Miki; Gao, Fei; Kim, Hyung-Wook; Ma, Kaizong; Bell, Jane M.; Rapoport, Stanley I.

    2009-01-01

    Few studies have examined effects of feeding animals a diet deficient in n-6 polyunsaturated fatty acids (PUFAs) but with an adequate amount of n-3 PUFAs. To do this, we fed post-weaning male rats a control n-6 and n-3 PUFA adequate diet and an n-6 deficient diet for 15 weeks, and measured stable lipid and fatty acid concentrations in different organs. The deficient diet contained nutritionally essential linoleic acid (LA,18:2n-6) as 2.3% of total fatty acids (10% of the recommended minimum LA requirement for rodents) but no arachidonic acid (AA, 20:4n-6), and an adequate amount (4.8% of total fatty acids) of α-linolenic acid (18:3n-3). The deficient compared with adequate diet did not significantly affect body weight, but decreased testis weight by 10%. AA concentration was decreased significantly in serum (−86%), brain (−27%), liver (−68%), heart (−39%), testis (−25%), and epididymal adipose tissue (−77%). Eicosapentaenoic (20:5n-3) and docosahexaenoic acid (22:6n-3) concentrations were increased in all but adipose tissue, and the total monounsaturated fatty acid concentration was increased in all organs. The concentration of 20:3n-9, a marker of LA deficiency, was increased by the deficient diet, and serum concentrations of triacylglycerol, total cholesterol and total phospholipid were reduced. In summary, 15 weeks of dietary n-6 PUFA deficiency with n-3 PUFA adequacy significantly reduced n-6 PUFA concentrations in different organs of male rats, while increasing n-3 PUFA and monounsaturated fatty acid concentrations. This rat model could be used to study metabolic, functional and behavioral effects of dietary n-6 PUFA deficiency. PMID:19073280

  8. Dynamic Changes in Amino Acid Concentration Profiles in Patients with Sepsis

    PubMed Central

    Xie, Aimei; Liu, Dan; Rao, Weiqiao; Lan, Liping; Li, Xuan; Li, Fang; Xiao, Kun; Wang, Huijuan; Yan, Peng; Li, Xin; Xie, Lixin

    2015-01-01

    Objectives The goal of this work was to explore the dynamic concentration profiles of 42 amino acids and the significance of these profiles in relation to sepsis, with the aim of providing guidance for clinical therapies. Methods Thirty-five critically ill patients with sepsis were included. These patients were further divided into sepsis (12 cases) and severe sepsis (23 cases) groups or survivor (20 cases) and non-survivor (15 cases) groups. Serum samples from the patients were collected on days 1, 3, 5, 7, 10, and 14 following intensive care unit (ICU) admission, and the serum concentrations of 42 amino acids were measured. Results The metabolic spectrum of the amino acids changed dramatically in patients with sepsis. As the disease progressed further or with poor prognosis, the levels of the different amino acids gradually increased, decreased, or fluctuated over time. The concentrations of sulfur-containing amino acids (SAAs), especially taurine, decreased significantly as the severity of sepsis worsened or with poor prognosis of the patient. The serum concentrations of SAAs, especially taurine, exhibited weak negative correlations with the Sequential Organ Failure Assessment (SOFA) (r=-0.319) and Acute Physiology and Chronic Health Evaluation (APACHE) II (r=-0.325) scores. The areas under the receiver operating characteristic curves of cystine, taurine, and SAA levels and the SOFA and APACHE II scores, which denoted disease prognosis, were 0.623, 0.674, 0.678, 0.86, and 0.857, respectively. Conclusions Critically ill patients with disorders of amino acid metabolism, especially of SAAs such as cystine and taurine, may provide an indicator of the need for the nutritional support of sepsis in the clinic. Trial Registration ClinicalTrial.gov identifier NCT01818830. PMID:25849571

  9. Milk fatty acids as possible biomarkers to early diagnose elevated concentrations of blood plasma nonesterified fatty acids in dairy cows.

    PubMed

    Jorjong, S; van Knegsel, A T M; Verwaeren, J; Lahoz, M Val; Bruckmaier, R M; De Baets, B; Kemp, B; Fievez, V

    2014-11-01

    Most cows encounter a state of negative energy balance during the periparturient period, which may lead to metabolic disorders and impaired fertility. The aim of this study was to assess the potential of milk fatty acids as diagnostic tools of detrimental levels of blood plasma nonesterified fatty acids (NEFA), defined as NEFA concentrations beyond 0.6 mmol/L, in a data set of 92 early lactating cows fed a glucogenic or lipogenic diet and subjected to 0-, 30-, or 60-d dry period before parturition. Milk was collected in wk 2, 3, 4, and 8 (n = 368) and blood was sampled weekly from wk 2 to 8 after parturition. Milk was analyzed for milk fatty acids and blood plasma for NEFA. Data were classified as "at risk of detrimental blood plasma NEFA" (NEFA ≥ 0.6 mmol/L) and "not at risk of detrimental blood plasma NEFA" (NEFA <0.6 mmol/L). Concentrations of 45 milk fatty acids and milk fat C18:1 cis-9-to-C15:0 ratio were subjected to a discriminant analysis. Milk fat C18:1 cis-9 revealed the most discriminating variable to identify detrimental blood plasma NEFA. A false positive rate of 10% allowed us to diagnose 46% of the detrimental blood plasma NEFA cases based on a milk fat C18:1 cis-9 concentration of at least 230 g/kg of milk fatty acids. Additionally, it was assessed whether the milk fat C18:1 cis-9 concentrations of wk 2 could be used as an early warning for detrimental blood plasma NEFA risk during the first 8 wk in lactation. Cows with at least 240 g/kg of C18:1 cis-9 in milk fat had about 50% chance to encounter blood plasma NEFA values of 0.6 mmol/L or more during the first 8 wk of lactation, with a false positive rate of 11.4%. Profit simulations were based on costs for cows suffering from detrimental blood plasma NEFA, and costs for preventive treatment based on daily dosing of propylene glycol for 3 wk. Given the relatively low incidence rate (8% of all observations), continuous monitoring of milk fatty acids during the first 8 wk of lactation to diagnose

  10. Effect of fluoride concentration in adhesives on morphology of acid-base resistant zones.

    PubMed

    Kirihara, Masaru; Inoue, Go; Nikaido, Toru; Ikeda, Masaomi; Sadr, Alireza; Tagami, Junji

    2013-01-01

    This study aimed to investigate the effect of fluoride concentration in adhesives on morphology of acid-base resistant zone (ABRZ). Seven experimental adhesives with different concentrations of NaF (0 wt%; F0 to 100 wt%: F100) were prepared based on the formulation of a commercially available adhesive (Clearfil Protect Bond, F100). The resin-dentin interface of the bonded specimen was subjected to demineralizing solution and NaOCl, sectioned, polished and argon-ion etched for SEM observation. Fluoride release from each adhesive was measured using an ion-selective electrode. Fluoride ion release from the adhesive linearly increased with higher NaF concentration. The ABRZ area increased significantly with higher NaF concentration except for F0, F10, and F20 (p<0.05). F100 showed the largest ABRZ, where a slope of acid-resistant dentin was clearly observed at the bottom of the ABRZ. The concentration of NaF in the two-step self-etching adhesive resin influenced the amount of dentin structure remaining after acid-challenge.

  11. Polyunsaturated fatty acid consumption and concentration among South Indian women during pregnancy.

    PubMed

    Dwarkanath, Pratibha; Muthayya, Sumithra; Thomas, Tinku; Vaz, Mario; Parikh, Panam; Mehra, Ruchika; Kurpad, Anura V

    2009-01-01

    In recent years there is growing interest on the role of long chain omega-3 polyunsaturated fatty acids (omega-3 LC-PUFA) in pregnancy and the growth and development of the offspring. We aim to characterize and provide baseline data on the intake of LCPUFA (omega-3 and omega-6) in a prospective cohort of 829 pregnant Indian women and report associations between LCPUFA intake and erythrocyte membrane phospholipid fatty acid concentration in a sub-group at baseline (1st trimester), the 2nd and 3rd trimesters of pregnancy. The dietary intake of all the macronutrients and of alpha-linolenic acid(ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) significantly increased over the 3 trimesters of pregnancy while that of omega-6 fatty acids (FA) remained unchanged. Median omega-3 FA intakes of ALA, EPA and DHA, however, were on average low at 0.56, 0.003 and 0.011 g/d, respectively while LA was 14.6 g/d during pregnancy. Consequently, the intake ratio of ALA to LA in the women in the present study was very low at 1:26. A significant decline in erythrocyte membrane arachidonic acid (AA) concentration but not of DHA was observed throughout pregnancy. This might be due to increased efficiency in terms of elongation of parent omega-3 FA. Dietary methods for improving the consumption of omega-3 FA need to be considered in the diets of young women as well as during pregnancy. As newborns primarily depend on placental transfer of omega-3 FA there is need to examine the omega-3 LC-PUFA concentration in infants of mother's with low intakes of omega-3 FA.

  12. Passive sampler for measurements of atmospheric nitric acid vapor (HNO3) concentrations.

    PubMed

    Bytnerowicz, A; Padgett, P E; Arbaugh, M J; Parker, D R; Jones, D P

    2001-12-05

    Nitric acid (HNO3) vapor is an important nitrogenous air pollutant responsible for increasing saturation of forests with nitrogen and direct injury to plants. The USDA Forest Service and University of California researchers have developed a simple and inexpensive passive sampler for monitoring air concentrations of HNO3. Nitric acid is selectively absorbed on 47-mm Nylasorb nylon filters with no interference from particulate NO3-. Concentrations determined with the passive samplers closely corresponded with those measured with the co-located honeycomb annular denuder systems. The PVC protective caps of standardized dimensions protect nylon filters from rain and wind and allow for reliable measurements of ambient HNO3 concentrations. The described samplers have been successfully used in Sequoia National Park, the San Bernardino Mountains, and on Mammoth Mountain in California.

  13. Postprandial triglyceride and free fatty acid metabolism in obese women after either endurance or resistance exercise.

    PubMed

    Davitt, Patrick M; Arent, Shawn M; Tuazon, Marc A; Golem, Devon L; Henderson, Gregory C

    2013-06-15

    We investigated the effects of two exercise modalities on postprandial triglyceride (TG) and free fatty acid (FFA) metabolism. Sedentary, obese women were studied on three occasions in randomized order: endurance exercise for 60 min at 60-65% aerobic capacity (E), ~60 min high-intensity resistance exercise (R), and a sedentary control trial (C). After exercise, a liquid-mixed meal containing [U-(13)C]palmitate was consumed, and subjects were studied over 7 h. Isotopic enrichment (IE) of plasma TG, plasma FFA, and breath carbon dioxide compared with meal IE indicated the contribution of dietary fat to each pool. Total and endogenously derived plasma TG content was reduced significantly in both E and R compared with C (P < 0.05), with no effect of exercise on circulating exogenous (meal-derived) TG content. Exogenous plasma FFA content was increased significantly following both E and R compared with C (P < 0.05), whereas total and endogenous FFA concentrations were elevated only in E (P < 0.05) compared with C. Fatty acid (FA) oxidation rates were increased significantly after E and R compared with C (P < 0.05), with no difference between exercise modalities. The present results indicate that E and R may be equally effective in reducing postprandial plasma TG concentration and enhancing lipid oxidation when the exercise sessions are matched for duration rather than for energy expenditure. Importantly, tracer results indicated that the reduction in postprandial lipemia after E and R exercise bouts is not achieved by enhanced clearance of dietary fat but rather, is achieved by reduced abundance of endogenous FA in plasma TG.

  14. High-fat diet alters serum fatty acid profiles in obesity prone rats: implications for in-vitro studies

    PubMed Central

    Liu, Tzu-Wen; Heden, Timothy D.; Morris, E. Matthew; Fritsche, Kevin L.; Vieira-Potter, Victoria J.; Thyfault, John P.

    2015-01-01

    High-fat diets (HFD) are commonly used in rodents to induce obesity, increase serum fatty acids, and induce lipotoxicity in various organs. In-vitro studies commonly utilize individual free fatty acids (FFA) to study lipid exposure in an effort to model what is occurring in-vivo, however, these approaches are not physiological as tissues are exposed to multiple fatty acids in-vivo. Here we characterize circulating lipids in obese-prone rats fed a HFD in both fasted and fed states with the goal of developing physiologically relevant fatty acid mixtures for subsequent in-vitro studies. Rats were fed a HFD (60% kcal fat) or a control diet (10% kcal fat) for 3 weeks; liver tissue, and both portal and systemic blood was collected. Fatty acid profiles and absolute concentrations of triglycerides (TAG) and FFA in the serum and TAG, diacylglycerol (DAG), and phospholipids (PL) in the liver were measured. Surprisingly, both systemic and portal serum TAG were ~40% lower in HFD-fed compared to controls. Overall, compared to the control diet, HFD feeding consistently induced an increase in the proportion of circulating polyunsaturated fatty acids (PUFA) with a concomitant decline in monounsaturated fatty acids (MUFA), and saturated fatty acids (SFA) in both serum TAG and FFA. The elevations of PUFA were mostly attributed to increases in n-6 PUFA, linoleic acid and arachidonic acid. In conclusion, fatty acid mixtures enriched with linoleic and arachidonic acid in addition to SFA and MUFA should be utilized for in-vitro studies attempting to model lipid exposures that occur during in-vivo HFD condition. PMID:26318121

  15. Dietary supplementation with cholesterol and docosahexaenoic acid affects concentrations of amino acids in tissues of young pigs

    PubMed Central

    Li, Peng; Kim, Sung Woo; Li, Xilong; Datta, Sujay; Pond, Wilson G.

    2013-01-01

    Cholesterol and docosahexaenoic acid (DHA) are important nutrients for neural development of infants. However, little is known about the effect of cholesterol or DHA on concentrations of amino acids (AA) in neonatal tissues. This study was conducted with the piglet (an established model for studying human infant nutrition) to test the hypothesis that dietary supplementation with the lipids may modulate AA availability in tissues. Sixteen newborn pigs were nursed by sows for 24 h and then assigned to one of four treatment groups, representing supplementation with 0.0% (control), 0.2% cholesterol, 0.2% DHA, or cholesterol plus DHA to the basal milk-formula. All piglets were euthanized at 49 days of age. In brain, cholesterol supplementation reduced (P < 0.05) concentrations of glutamate, serine, glutamine, threonine, β-alanine, alanine, methionine, isoleucine, leucine, and γ-aminobutyrate but increased (P < 0.05) concentrations of glycine and lysine, whereas DHA supplementation similarly affected (P < 0.05) concentrations of the same AA (except for isoleucine and lysine) and taurine. In addition, concentrations of most AA in liver, muscle and plasma were substantially altered by dietary supplementation of cholesterol and DHA in a tissue-dependent manner. Further, DHA reduced concentrations of carnosine in skeletal muscle, as well as ammonia in both plasma and brain. The results reveal that cholesterol and DHA can regulate AA metabolism and availability in various tissues of piglets. These novel findings have important implications for designing the next generation of infant formula to optimize neonatal growth and development. PMID:18972185

  16. Strong Relationships in Acid-Base Chemistry – Modeling Protons Based on Predictable Concentrations of Strong Ions, Total Weak Acid Concentrations, and pCO2

    PubMed Central

    Kellum, John A.

    2016-01-01

    Understanding acid-base regulation is often reduced to pigeonholing clinical states into categories of disorders based on arterial blood sampling. An earlier ambition to quantitatively explain disorders by measuring production and elimination of acid has not become standard clinical practice. Seeking back to classical physical chemistry we propose that in any compartment, the requirement of electroneutrality leads to a strong relationship between charged moieties. This relationship is derived in the form of a general equation stating charge balance, making it possible to calculate [H+] and pH based on all other charged moieties. Therefore, to validate this construct we investigated a large number of blood samples from intensive care patients, where both data and pathology is plentiful, by comparing the measured pH to the modeled pH. We were able to predict both the mean pattern and the individual fluctuation in pH based on all other measured charges with a correlation of approximately 90% in individual patient series. However, there was a shift in pH so that fitted pH in general is overestimated (95% confidence interval -0.072–0.210) and we examine some explanations for this shift. Having confirmed the relationship between charged species we then examine some of the classical and recent literature concerning the importance of charge balance. We conclude that focusing on the charges which are predictable such as strong ions and total concentrations of weak acids leads to new insights with important implications for medicine and physiology. Importantly this construct should pave the way for quantitative acid-base models looking into the underlying mechanisms of disorders rather than just classifying them. PMID:27631369

  17. Aggregation and stability of Fe2O3:Influence of humic acid concentration, Fe2O3 concentration and pH

    NASA Astrophysics Data System (ADS)

    Ahmad, Nur Suraya; Radiman, Shahidan; Yaacob, Wan Zuhairi Wan

    2016-11-01

    The scenario of released nanoparticles from consumer product into the environment especially natural waters are increased concern nowadays. Assessing their aggregation and stability under environmental conditions are important to determining their fate and behavior in natural waters. The aggregation behavior of Fe2O3 nanoparticles (NPs) was investigated at variable concentration of humic acid, Fe2O3 NPs concentration and pH variation in solution using dynamic light scattering to measure their z-average hydrodynamic diameter and zeta potential value. The stability are then evaluated by assessing their aggregation and disaggregation. Increasing humic acid concentration induced the disaggregation of Fe2O3 NPs. At a lower concentrations of Fe2O3 (< 30 mg/L), aggregate formed and disaggregation take place with increasing Fe2O3 concentration (50, 100, 150, 200 mg/L). The maximum aggregation was found in pH 4 at a constant concentration of humic acid of 100 mg/L and concentration of Fe2O3 (100 mg/L). High pH (>5) of solution induced disaggregation of suspensions and make it stable in the solution. TEM imaging have confirmed that Fe2O3 NPs aggregate and disaggregate in the presence of humic acid. Our study result shows that aggregation and stability of Fe2O3 NPs were depends on concentration of humic acid, concentration of NPs itself and the pH of the solutions.

  18. Separate and Concentrate Lactic Acid Using Combination of Nanofiltration and Reverse Osmosis Membranes

    NASA Astrophysics Data System (ADS)

    Li, Yebo; Shahbazi, Abolghasem; Williams, Karen; Wan, Caixia

    The processes of lactic acid production include two key stages, which are (a) fermentation and (b) product recovery. In this study, free cell of Bifidobacterium longum was used to produce lactic acid from cheese whey. The produced lactic acid was then separated and purified from the fermentation broth using combination of nanofiltration and reverse osmosis membranes. Nanofiltration membrane with a molecular weight cutoff of 100-400 Da was used to separate lactic acid from lactose and cells in the cheese whey fermentation broth in the first step. The obtained permeate from the above nanofiltration is mainly composed of lactic acid and water, which was then concentrated with a reverse osmosis membrane in the second step. Among the tested nanofiltration membranes, HL membrane from GE Osmonics has the highest lactose retention (97±1%). In the reverse osmosis process, the ADF membrane could retain 100% of lactic acid to obtain permeate with water only. The effect of membrane and pressure on permeate flux and retention of lactose/lactic acid was also reported in this paper.

  19. Separate and concentrate lactic acid using combination of nanofiltration and reverse osmosis membranes.

    PubMed

    Li, Yebo; Shahbazi, Abolghasem; Williams, Karen; Wan, Caixia

    2008-03-01

    The processes of lactic acid production include two key stages, which are (a) fermentation and (b) product recovery. In this study, free cell of Bifidobacterium longum was used to produce lactic acid from cheese whey. The produced lactic acid was then separated and purified from the fermentation broth using combination of nanofiltration and reverse osmosis membranes. Nanofiltration membrane with a molecular weight cutoff of 100-400 Da was used to separate lactic acid from lactose and cells in the cheese whey fermentation broth in the first step. The obtained permeate from the above nanofiltration is mainly composed of lactic acid and water, which was then concentrated with a reverse osmosis membrane in the second step. Among the tested nanofiltration membranes, HL membrane from GE Osmonics has the highest lactose retention (97 +/- 1%). In the reverse osmosis process, the ADF membrane could retain 100% of lactic acid to obtain permeate with water only. The effect of membrane and pressure on permeate flux and retention of lactose/lactic acid was also reported in this paper.

  20. Changes of amino acid concentrations in the rat vestibular nuclei after midline lesions.

    PubMed

    Sun, Yizhe; Godfrey, Donald A; Godfrey, Matthew A; Hong, Steven; Jin, Yong-Ming; Rubin, Allan M

    2011-01-01

    Changes in concentrations of amino acids, especially GABA, glutamate, and aspartate, occur in vestibular nuclei after removal of cerebellar and labyrinth inputs. Here, we examined the effects of transecting midline-crossing connections between the two vestibular nuclear complexes, which especially include commissural connections. Three rats were euthanized at each of 2, 7, and 30 days after a midline cut at the level of the vestibular nuclei. Two sham-lesioned rats were prepared for surgery but no cut made. Samples of superior (SuVN), dorsal and ventral lateral (LVNd and LVNv), dorsal and ventral medial (MVNd and MVNv), and spinal vestibular nuclei (SpVN) were microdissected from freeze-dried coronal sections and assayed for amino acid concentrations. Reductions of GABA concentration occurred by 2 days and continued through 30 days after surgery in most regions. Glutamate and aspartate concentrations decreased by 2 days in LVN and MVN, then glutamate showed some recovery by 30 days. Glutamine and taurine concentrations increased in almost all regions. Glycine concentration decreased in MVN and LVNv. Our results support association of GABA, glutamate, aspartate, and to some extent glycine, with vestibular crossed connections. Comparisons to our previous studies suggest some complex lesion effects, especially in LVNd.

  1. The concentration of ascorbic acid and glutathione in 13 provenances of Acacia melanoxylon.

    PubMed

    Wujeska-Klause, Agnieszka; Bossinger, Gerd; Tausz, Michael

    2016-04-01

    Climate change can negatively affect sensitive tree species, affecting their acclimation and adaptation strategies. A common garden experiment provides an opportunity to test whether responses of trees from different provenances are genetically driven and if this response is related to factors at the site of origin. We hypothesized that antioxidative defence systems and leaf mass area ofAcacia melanoxylonR. Br. samples collected from different provenances will vary depending on local rainfall. Thirteen provenances ofA. melanoxylonoriginating from different rainfall habitats (500-2000 mm) were grown for 5 years in a common garden. For 2 years, phyllode samples were collected during winter and summer, for measurements of leaf mass area and concentrations of glutathione and ascorbic acid. Leaf mass area varied between seasons, years and provenances ofA. melanoxylon, and an increase was associated with decreasing rainfall at the site of origin. Ascorbic acid and glutathione concentrations varied between seasons, years (i.e., environmental factors) and among provenances ofA. melanoxylon In general, glutathione and ascorbic acid concentrations were higher in winter compared with summer. Ascorbic acid and glutathione were different among provenances, but this was not associated with rainfall at the site of origin.

  2. A Novel RSSI Prediction Using Imperialist Competition Algorithm (ICA), Radial Basis Function (RBF) and Firefly Algorithm (FFA) in Wireless Networks

    PubMed Central

    Goudarzi, Shidrokh; Haslina Hassan, Wan; Abdalla Hashim, Aisha-Hassan; Soleymani, Seyed Ahmad; Anisi, Mohammad Hossein; Zakaria, Omar M.

    2016-01-01

    This study aims to design a vertical handover prediction method to minimize unnecessary handovers for a mobile node (MN) during the vertical handover process. This relies on a novel method for the prediction of a received signal strength indicator (RSSI) referred to as IRBF-FFA, which is designed by utilizing the imperialist competition algorithm (ICA) to train the radial basis function (RBF), and by hybridizing with the firefly algorithm (FFA) to predict the optimal solution. The prediction accuracy of the proposed IRBF–FFA model was validated by comparing it to support vector machines (SVMs) and multilayer perceptron (MLP) models. In order to assess the model’s performance, we measured the coefficient of determination (R2), correlation coefficient (r), root mean square error (RMSE) and mean absolute percentage error (MAPE). The achieved results indicate that the IRBF–FFA model provides more precise predictions compared to different ANNs, namely, support vector machines (SVMs) and multilayer perceptron (MLP). The performance of the proposed model is analyzed through simulated and real-time RSSI measurements. The results also suggest that the IRBF–FFA model can be applied as an efficient technique for the accurate prediction of vertical handover. PMID:27438600

  3. TCF2 attenuates FFA-induced damage in islet β-cells by regulating production of insulin and ROS.

    PubMed

    Quan, Xiaojuan; Zhang, Lin; Li, Yingna; Liang, Chunlian

    2014-07-30

    Free fatty acids (FFAs) are cytotoxic to pancreatic islet β-cells and play a crucial role in the diabetes disease process. A recent study revealed a down-regulation of transcription factor 2 (TCF2) levels during FFA-mediated cytotoxicity in pancreatic β-cells. However, its function during this process and the underlying mechanism remains unclear. In this study, treatment with palmitic acid (PA) at high levels (400 and 800 μM) decreased β-cell viability and TCF2 protein expression, along with the glucose-stimulated insulin secretion (GSIS). Western and RT-PCR analysis confirmed the positive regulatory effect of TCF2 on GSIS through promotion of the key regulators pancreatic duodenal homeobox-1 (PDX1) and glucose transporter 2 (GLUT2) in β-cells. In addition, both PI3K/AKT and MEK/ERK showed decreased expression in PA (800 μM)-treated β-cells. Overexpression of TCF2 could effectively restore the inhibitory effect of PA on the activation of PI3K/AKT and MEK/ERK as well as β-cell viability, simultaneously, inhibited PA-induced reactive oxygen species (ROS) generation. After blocking the PI3K/AKT and MAPK/ERK signals with their specific inhibitor, the effect of overexpressed TCF2 on β-cell viability and ROS production was obviously attenuated. Furthermore, a protective effect of TCF2 on GSIS by positive modulation of JNK-PDX1/GLUT2 signaling was also confirmed. Accordingly, our study has confirmed that TCF2 positively modulates insulin secretion and further inhibits ROS generation via the PI3K/AKT and MEK/ERK signaling pathways. Our work may provide a new therapeutic target to achieve prevention and treatment of diabetes.

  4. Capillary electrophoresis method with UV-detection for analysis of free amino acids concentrations in food.

    PubMed

    Omar, Mei Musa Ali; Elbashir, Abdalla Ahmed; Schmitz, Oliver J

    2017-01-01

    Simple and inexpensive capillary electrophoresis with UV-detection method (CE-UV) was optimized and validated for determination of six amino acids namely (alanine, asparagine, glutamine, proline, serine and valine) for Sudanese food. Amino acids in the samples were derivatized with 4-chloro-7-nitro-2,1,3-benzoxadiazole (NBD-Cl) prior to CE-UV analysis. Labeling reaction conditions (100mM borate buffer at pH 8.5, labeling reaction time 60min, temperature 70°C and NBD-Cl concentration 40mM) were systematically investigated. The optimal conditions for the separation were 100mM borate buffer at pH 9.7 and detected at 475nm. The method was validated in terms of linearity, limit of detection (LOD), limit of quantification (LOQ), precision (repeatability) (RSD%) and accuracy (recovery). Good linearity was achieved for all amino acids (r(2)>0.9981) in the concentration range of 2.5-40mg/L. The LODs in the range of 0.32-0.56mg/L were obtained. Recoveries of amino acids ranging from 85% to 108%, (n=3) were obtained. The validated method was successfully applied for the determination of amino acids for Sudanese food samples.

  5. Blood concentrations of amino acids, glucose and lactate during experimental swine dysentery.

    PubMed

    Jonasson, R; Essén-Gustavsson, B; Jensen-Waern, M

    2007-06-01

    The aim of this study was to examine blood concentrations of amino acids, glucose and lactate in association with experimental swine dysentery. Ten pigs (approximately 23kg) were orally inoculated with Brachyspira hyodysenteriae. Eight animals developed muco-haemorrhagic diarrhoea with impaired general appearance, changes in white blood cell counts and increased levels of the acute phase protein Serum Amyolid A. Blood samples were taken before inoculation, during the incubation period, during clinical signs of dysentery and during recovery. Neither plasma glucose nor lactate concentrations changed during the course of swine dysentery, but the serum concentrations of gluconeogenic non-essential amino acids decreased during dysentery. This was mainly due to decreases in alanine, glutamine, serine and tyrosine. Lysine increased during dysentery and at the beginning of the recovery period, and leucine increased during recovery. Glutamine, alanine and tyrosine levels show negative correlations with the numbers of neutrophils and monocytes. In conclusion, swine dysentery altered the blood concentrations of amino acids, but not of glucose or lactate.

  6. Diurnal variations in the plasma concentrations of mevalonic acid in patients with abetalipoproteinaemia.

    PubMed

    Pappu, A S; Illingworth, D R

    1994-10-01

    Previous studies have demonstrated that changes in the rates of cholesterol biosynthesis can be evaluated by the determination of plasma concentrations of sterol intermediates, including mevalonic acid and lathosterol and that, in normal human subjects, a diurnal rhythm exists in which the highest concentrations of sterol intermediates are observed at night. The factors responsible for this diurnal rhythm in cholesterol synthesis are, however, unknown. To test the hypothesis that the nocturnal increase in cholesterol biosynthesis is attributable to a reduced rate of hepatic uptake of chylomicron remnants at night as compared to higher rates of uptake during the daytime in response to alimentary lipaemia, we have examined the diurnal rhythm of mevalonic acid in six normal volunteers and three patients with phenotypic abetalipoproteinaemia. The latter patients do not absorb appreciable amounts of dietary cholesterol and are unable to synthesize chylomicron particles. Plasma concentrations of mevalonic acid exhibited a diurnal rhythm in the normal subjects, and the highest plasma concentrations were observed between 24.00 hours/04.00 hours. A similar rhythm was observed in the plasma of patients with abetalipoproteinaemia. These results suggest that the nocturnal increase in cholesterol biosynthesis which occurs in humans is not attributable to reduced hepatic uptake of chylomicron remnants at night; further studies are needed to better define those factors which influence the periodicity of cholesterol biosynthesis in humans.

  7. Effects of phosphoric acid concentration on oxygen reduction kinetics at platinum

    SciTech Connect

    Hsueh, K.L.; Chin, D.T.; Gonzalez, E.R.; Srinivasan, S.

    1984-04-01

    The oxygen reduction reaction was investigated at platinum electrodes in phosphoric acid in the concentration range 0.7M(6.6%) to 17.5M(95%) at 25/sup 0/C using the rotating ring-disk electrode technique. As a complement, cyclic voltammograms on platinum and potentials of zero charge of mercury were obtained as a function of phosphoric aci concentration. The mechanism of the oxygen electrode reaction is discussed in terms of the direct four-electron transfer reduction to water and the formation of hydrogen peroxide as an intermediate in a parallel two-electron transfer reaction The rate constants of the intermediate reaction steps were calculated from the ring-disk data for various potentials and electrolyte concentrations. The characteristics of the reaction were found to be markedly dependent on the concentration of phosphoric acid. These results are interpreted in terms of changes in oxygen solubility, proton activity, and double laye characteristics when passing over from a water to a phosphoric acid solvent structure.

  8. Adenosine plasma level correlates with homocysteine and uric acid concentrations in patients with coronary artery disease.

    PubMed

    Fromonot, J; Deharo, P; Bruzzese, L; Cuisset, T; Quilici, J; Bonatti, S; Fenouillet, E; Mottola, G; Ruf, J; Guieu, R

    2016-03-01

    The role of hyperhomocysteinemia in coronary artery disease (CAD) patients remains unclear. The present study evaluated the relationship between homocysteine (HCys), adenosine plasma concentration (APC), plasma uric acid, and CAD severity evaluated using the SYNTAX score. We also evaluated in vitro the influence of adenosine on HCys production by hepatoma cultured cells (HuH7). Seventy-eight patients (mean age ± SD: 66.3 ± 11.3; mean SYNTAX score: 19.9 ± 12.3) and 30 healthy subjects (mean age: 61 ± 13) were included. We incubated HuH7 cells with increasing concentrations of adenosine and addressed the effect on HCys level in cell culture supernatant. Patients vs. controls had higher APC (0.82 ± 0.5 μmol/L vs 0.53 ± 0.14 μmol/L; p < 0.01), HCys (15 ± 7.6 μmol/L vs 6.8 ± 3 μmol/L, p < 0.0001), and uric acid (242.6 ± 97 vs 202 ± 59, p < 0.05) levels. APC was correlated with HCys and uric acid concentrations in patients (Pearson's R = 0.65 and 0.52; p < 0.0001, respectively). The SYNTAX score was correlated with HCys concentration. Adenosine induced a time- and dose-dependent increase in HCys in cell culture. Our data suggest that high APC is associated with HCys and uric acid concentrations in CAD patients. Whether the increased APC participates in atherosclerosis or, conversely, is part of a protective regulation process needs further investigations.

  9. Relative Amino Acid Concentrations as a Signature for Parent Body Processes of Carbonaceous Chondrites

    NASA Technical Reports Server (NTRS)

    Botta, Oliver; Glavin, Daniel P.; Kminek, Gerhard; Bada, Jeffrey L.

    2002-01-01

    Most meteorites are thought to have originated from objects in the asteroid belt. Carbonaceous chondrites, which contain significant amounts of organic carbon including complex organic compounds, have also been suggested to be derived from comets. The current model for the synthesis of organic compounds found in carbonaceous chondrites includes the survival of interstellar organic compounds and the processing of some of these compounds on the meteoritic parent body. The amino acid composition of five CM carbonaceous chondrites, two CIs, one CR, and one CV3 have been measured using hot water extraction-vapor hydrolysis, OPA/NAC derivatization and high-performance liquid chromatography (HPLC). Total amino acid abundances in the bulk meteorites as well as the amino acid concentrations relative to glycine = 1.0 for beta-alanine, alpha-aminoisobutyric acid and D-alanine were determined. Additional data for three Antarctic CM meteorites were obtained from the literature. All CM meteorites analyzed in this study show a complex distribution of amino acids and a high variability in total concentration ranging from approx. 15,300 to approx. 5800 parts per billion (ppb), while the CIs show a total amino acid abundance of approx. 4300 ppb. The relatively (compared to glycine) high AIB content found in all the CMs is a strong indicator that Strecker-cyanohydrin synthesis is the dominant pathway for the formation of amino acids found in these meteorites. The data from the Antarctic CM carbonaceous chondrites are inconsistent with the results from the other CMs, perhaps due to influences from the Antarctic ice that were effective during their residence time. In contrast to CMs, the data from the CI carbonaceous chondrites indicate that the Strecker synthesis was not active on their parent bodies.

  10. Esterification free fatty acid in palm fatty acid distillate using sulfonated rice husk ash catalyst

    NASA Astrophysics Data System (ADS)

    Hidayat, Arif; Sutrisno, Bachrun

    2017-01-01

    Indonesia, as one of the biggest palm oil producers and exporters in the world, is producing large amounts of low-grade oil such as Palm Fatty Acid Distillate (PFAD) from palm oil industries. The use of PFAD can reduce the cost of biodiesel production significantly, which makes PFAD a highly potential alternative feedstock for biodiesel production. In this paper, the esterification of free fatty acid (FFA) on PFAD was studied using rice husk ash (RHA) as heterogeneous catalyst. The rice husk ash catalyst was synthesized by sulfonation using concentrated sulfuric acid. The RHA catalyst were characterized by using different techniques, such as porosity analysis, Fourier transform infrared (FT-IR) spectroscopy, total number of acid sites and elemental analysis. The effects of the molar ratio of methanol to PFAD (1-10%), the molar ratio of methanol to PFAD (4:1-10:1), and the reaction temperature (40-60°C) were studied for the conversion of FFA to optimize the reaction conditions. The results showed that the optimal conditions were an methanol to PFAD molar ratio of 10:1, the catalyst amount of 10 wt% of PFAD, and reaction temperature of 60°C.

  11. A field investigation of the relationship between zinc and acid volatile sulfide concentrations in freshwater sediments

    USGS Publications Warehouse

    Ankley, Gerald T.; Liber, Karsten; Call, Daniel J.; Markee, Thomas P.; Canfield, Timothy J.; Ingersoll, Christopher G.

    1996-01-01

    Understanding relationships between cationic metals such as cadmium, copper, nickel, lead and zinc, and amorphous iron sulfides, measured as acid volatile sulfide (AVS), is key to predicting metal bioavailability and toxicity insediments. The objective of the present study was to assess seasonal and spatial variations of AVS in freshwater sediments contaminated with zinc. Sediments were sampled from three streams with varying levels of zinc contamination at two different times, March and June of 1995, representing cold- and warm-weather situations. Interstitial (pore) water concentrations of zinc, and solid phase concentrations of AVS and zinc were measured in surficial and deep sediment horizons. Toxicity tests (10-d) with the amphipodHyalella azteca were conducted using intact cores. Sediment zinc concentrations from six sites within the primary test stream differed by about five-fold, and also varied seasonally. Acid volatile sulfide concentrations were generally lower than those of zinc, and pore water zinc concentrations typically were elevated. There was a positive correlation between solid-phase AVS and zinc concentrations, suggesting that the system was dominated by zinc, as opposed to iron sulfides. In contrast to expectations arising from some studies of seasonal variations of AVS in iron-dominated systems, AVS concentrations were smaller in June than in March. However, this was likely due to a major storm event and associated sediment scouring before the June sampling, rather than to seasonal processes related to variations in temperature and dissolved oxygen. Based upon an indirect analysis of depth variations in AVS, there was some indication that zinc sulfide might be less prone to oxidation than iron sulfide. There was a strong correlation between toxicity of the sediment samples toH. azteca and interstitial water concentrations of zinc; however, the possible contribution of other contaminants to sediment toxicity cannot be dismissed.

  12. Microbial production of itaconic acid: developing a stable platform for high product concentrations.

    PubMed

    Kuenz, Anja; Gallenmüller, Yvonne; Willke, Thomas; Vorlop, Klaus-Dieter

    2012-12-01

    Biotechnologically produced itaconic acid (IA) is a promising organic acid with a wide range of applications and the potential to open up new application fields in the area of polymer chemistry, pharmacy, and agriculture. In this study, a systematic process optimization was performed with an own isolated strain of Aspergillus terreus and transferred from a 250-mL to a 15-L scale. An IA concentration of 86.2 g/L was achieved within 7 days with an overall productivity of 0.51 g/(L h), a maximum productivity of 1.2 g/(L h), and a yield of 86 mol%. A cultivation of other well-known A. terreus strains with the developed process showed no significant differences. Based on this, a process is developed providing a high final IA concentration independent of the used strain combined with high reproducibility.

  13. A Concentrated Hydrochloric Acid-based Method for Complete Recovery of DNA from Bone.

    PubMed

    Huynen, Leon; Lambert, David M

    2015-11-01

    The successful extraction of DNA from historical or ancient animal bone is important for the analysis of discriminating genetic markers. Methods used currently rely on the digestion of bone with EDTA and proteinase K, followed by purification with phenol/chloroform and silica bed binding. We have developed a simple concentrated hydrochloric acid-based method that precludes the use of phenol/chloroform purification and can lead to a several-fold increase in DNA yield when compared to other commonly used methods. Concentrated hydrochloric acid was shown to dissolve most of the undigested bone and allowed the efficient recovery of DNA fragments <100 bases in length. This method should prove useful for the recovery of DNAs from highly degraded animal bone, such as that found in historical or ancient samples.

  14. An intercomparison of measurement systems for vapor and particulate phase concentrations of formic and acetic acids

    NASA Technical Reports Server (NTRS)

    Keene, William C.; Talbot, Robert W.; Andreae, Meinrat O.; Beecher, Kristene; Berresheim, Harold

    1989-01-01

    During June 1986, eight systems for measuring vapor phase and four for measuring particulate phase concentrations of formic acid (HCOOH) and acetic acid (CH3COOH) were intercompared in central Virginia. HCOOH and CH3COOH vapors were sampled by condensate, mist, Chromosorb 103 GC resin, NaOH-coated annular denuders, NaOH-impregnated quartz filters, K2CO3 and NaCO3-impregnated cellulose filters, and Nylasorb membranes. Atmospheric aerosol was collected on Teflon and Nuclepore filters using both hi-vol and lo-vol systems to measure particulate phase concentrations. Performances of the mist chamber and K2CO3-impregnated filter techniques were evaluated using zero air and ambient air spiked with HCOOH(g) and CH3COOH(g), and formaldehyde from permeation sources. The advantages and drawbacks of these methods are reported and discussed.

  15. Rhodamine B conjugates of triterpenoic acids are cytotoxic mitocans even at nanomolar concentrations.

    PubMed

    Sommerwerk, Sven; Heller, Lucie; Kerzig, Christoph; Kramell, Annemarie E; Csuk, René

    2017-02-15

    Triterpenoic acids 1-6 exhibited very low or no cytotoxicity at all, but their corresponding 2,3-di-O-acetyl-piperazinyl amides 13-18 showed low EC50 values for several human tumor cell lines. Their cytotoxicity, however, was also high for the non-malignant mouse fibroblasts NIH 3T3. A significant improvement was achieved by preparing the rhodamine B derivatives 19-24. While rhodamine B is not cytotoxic (up to a concentration of 30μM - cut-off of the assay), the triterpenoid piperazine-spacered rhodamine B derivatives were cytotoxic in nano-molar concentration. Compound 24 (a diacetylated maslinic acid derivative) was most toxic for several human tumor cell lines but less toxic for mouse fibroblasts NIH 3T3. Staining and double-staining experiments revealed 24 to act as a mitocan.

  16. Corn stover saccharification with concentrated sulfuric acid: effects of saccharification conditions on sugar recovery and by-product generation.

    PubMed

    Liu, Ze-Shen; Wu, Xiao-Lei; Kida, Kenji; Tang, Yue-Qin

    2012-09-01

    Although concentrated sulfuric acid saccharification is not a novel method for breaking down lignocellulosic biomass, the process by which saccharification affects biomass decomposition, sugar recovery, and by-product generation is not well studied. The present study employed Taguchi experimental design to study the effects of seven parameters on corn stover concentrated sulfuric acid saccharification. The concentration of sulfuric acid and the temperature of solubilization significantly affect corn stover decomposition. They also have significant effects on glucose and xylose recoveries. Low generation of furfural and 5-hydroxymethyl-2-furfural (5HMF) was noted and organic acids were the main by-products detected in the hydrolysate. Temperature also significantly affected the generation of levulinic acid and formic acid; however, acetic acid generation was not significantly influenced by all seven parameters. The ratio of acid to feedstock significantly affected glucose recovery, but not total sugar recovery. The corn stover hydrolysate was well fermented by both glucose- and xylose-fermenting yeast strains.

  17. Hyperinsulinemia and skeletal muscle fatty acid trafficking

    PubMed Central

    Kanaley, Jill A.; Shadid, Samyah; Sheehan, Michael T.; Guo, ZengKui

    2013-01-01

    We hypothesized that insulin alters plasma free fatty acid (FFA) trafficking into intramyocellular (im) long-chain acylcarnitines (imLCAC) and triglycerides (imTG). Overnight-fasted adults (n = 41) received intravenous infusions of [U-13C]palmitate (0400–0900 h) and [U-13C]oleate (0800–1400 h) to label imTG and imLCAC. A euglycemic-hyperinsulinemic (1.0 mU·kg fat-free mass−1·min−1) clamp (0800–1400 h) and two muscle biopsies (0900 h, 1400 h) were performed. The patterns of [U-13C]palmitate incorporation into imTG-palmitate and palmitoylcarnitine were similar to those we reported in overnight postabsorptive adults (saline control); the intramyocellular palmitoylcarnitine enrichment was not different from and correlated with imTG-palmitate enrichment for both the morning (r = 0.38, P = 0.02) and afternoon (r = 0.44, P = 0.006) biopsy samples. Plasma FFA concentrations, flux, and the incorporation of plasma oleate into imTG-oleate during hyperinsulinemia were ∼1/10th of that observed in the previous saline control studies (P < 0.001). At the time of the second biopsy, the enrichment in oleoylcarnitine was <25% of that in imTG-oleate and was not correlated with imTG-oleate enrichment. The intramyocellular nonesterified fatty acid-palmitate-to-imTG-palmitate enrichment ratio was greater (P < 0.05) in women than men, suggesting that sex differences in intramyocellular palmitate trafficking may occur under hyperinsulinemic conditions. We conclude that plasma FFA trafficking into imTG during hyperinsulinemia is markedly suppressed, and these newly incorporated FFA fatty acids do not readily enter the LCAC preoxidative pools. Hyperinsulinemia does not seem to inhibit the entry of fatty acids from imTG pools that were labeled under fasting conditions, possibly reflecting the presence of two distinct imTG pools that are differentially regulated by insulin. PMID:23820622

  18. An experimental and modeling study of humic acid concentration effect on H(+) binding: Application of the NICA-Donnan model.

    PubMed

    Vidali, Roza; Remoundaki, Emmanouela; Tsezos, Marios

    2009-11-15

    Humic substances are the most abundant components of the colloidal and the dissolved fraction of natural organic matter (NOM) and they are characterized by a strong binding capacity for both metals and organic pollutants, affecting their mobility and bioavailability. The understanding of the humic acidic character is the first necessary step for the study of the mechanisms of binding of other positively charged soluble metal species by humic molecules. The present work, which constitutes part of the Ph.D. thesis of Roza Vidali, reports results on the influence of the concentration of humic acids on the binding of protons obtained through both an experimental and a modeling approach. A reference purified peat humic acid (PPHA) isolated by the International Humic Substances Society (IHSS) and a humic acid from a Greek soil (GHA) were experimentally studied at various humic acid concentrations, ranging from 20 to 200mgL(-1). The proton binding isotherms obtained at different humic acid concentrations have shown that proton binding is dependent on the concentration of both humic acids. Proton binding experimental data were fitted to the NICA-Donnan model and the model parameter values were calculated for humic acid concentrations of 20 and >or=100mgL(-1). The results obtained for the NICA-Donnan parameters at humic acid concentrations >or=100mgL(-1) are in excellent agreement with those reported in the literature. However, these model parameter values cannot be used for modeling and predicting cation binding in natural aquatic systems, where humic acid concentrations are much lower. Two sets of the NICA-Donnan parameters are reported: one for humic acid concentrations of >or=100mgL(-1) and one for humic acid concentration of 20mgL(-1). The significance of the parameters values for each concentration level is also discussed.

  19. Decadal variations of rainwater formic and acetic acid concentrations in Wilmington, NC, USA

    NASA Astrophysics Data System (ADS)

    Willey, Joan D.; Glinski, Donna A.; Southwell, Melissa; Long, Michael S.; Avery, G. Brooks, Jr.; Kieber, Robert J.

    2011-02-01

    Concentrations of formic and acetic acid from January 2008 through March 2009 were compared to two previous studies at this location (conducted in 1987-1990 and 1996-1998) in order to quantify the extent to which temporal changes in DOC and pH can be explained by changes in these organic acids. The volume weighted 2008 formic and acetic acid concentrations (5.6 and 2.6 μM respectively) have decreased dramatically compared with those observed during the 1996-1998 study (9.9 and 7.3 μM) and are also lower than concentrations observed in the 1987-1990 study (7.4 and 3.6 μM). Changes in formic and acetic acids between 1996-97 and 2008 can account for approximately 50% of the DOC change and 40% of the H + change in rainwater over this same time period. These changes are most pronounced during the growing season, which is also the tourist and high traffic season at this location. Determining causation of these changes is difficult due to multiple biogenic and anthropogenic sources. However, the ratio of formic to acetic acid has also reverted back to a value consistent with reduced vehicular emissions, possibly related to the introduction of improved emission control technology including the use of reformulated gasoline in the late 1990's. Long term monitoring of seasonal, annual, and decadal trends will be of critical importance for evaluating the effects of future changes to atmospheric inputs such as the increased use of ethanol and other alternative fuels.

  20. Concentration-dependent mode of interaction of angiotensin II receptor blockers with uric acid transporter.

    PubMed

    Iwanaga, Takashi; Sato, Masanobu; Maeda, Tomoji; Ogihara, Toshio; Tamai, Ikumi

    2007-01-01

    Serum uric acid (SUA) is currently recognized as a risk factor for cardiovascular disease. It has been reported that an angiotensin II receptor blocker (ARB), losartan, decreases SUA level, whereas other ARBs, such as candesartan, have no lowering effect. Because the renal uric acid transporter (URAT1) is an important factor controlling the SUA level, we examined the involvement of URAT1 in those differential effects of various ARBs on SUA level at clinically relevant concentrations. This study was done by using URAT1-expressing Xenopus oocytes. Losartan, pratosartan, and telmisartan exhibited cis-inhibitory effects on the uptake of uric acid by URAT1, whereas at higher concentrations, only telmisartan did, and these ARBs reduced the uptake in competitive inhibition kinetics. On the other hand, candesartan, EXP3174 [2-n-butyl-4-chloro-1-[(2'-(1H-tetrazol-5-yl)biphenyl-4-yI)methyl]imidazole-5-carboxylic acid] (a major metabolite of losartan), olmesartan, and valsartan were not inhibitory. Preloading of those ARBs in the oocytes enhanced the URAT1-mediated uric acid uptake, showing a trans-stimulatory effect. The present study is a first demonstration of the differential effects of ARBs on URAT1 that some ARBs are both cis-inhibitory and trans-stimulatory, depending on concentration, whereas others exhibit either a trans-stimulatory or cis-inhibitory effect alone, which could explain the clinically observed differential effects of ARBs on SUA level. Furthermore, it was found that such differential effects of ARBs on URAT1 could be predicted from the partial chemical structures of ARBs, which will be useful information for the appropriate use and development of ARBs without an increase of SUA.

  1. Determination of pyruvic acid concentration using a bioluminescence system from Photobacterium leiognathi.

    PubMed

    Xuan, Guanhua; Lu, Xiaodong; Wang, Jingxue; Lin, Hong; Liu, Huihui

    2015-06-01

    A novel, highly sensitive and selective bacterial luminescence method for the detection of pyruvic acid (PA) is reported here. This method is based on a reaction system catalyzed by lactate dehydrogenase (LDH) with the bacterial luciferase-FMN:NADH oxidoreductase bioluminescence system in vitro. The reduced nicotinamide adenine dinucleotide (NADH) involved in the LDH reaction system could be quantitatively analyzed by the bioluminescence system. A good linear relationship between the luminescence intensity and pyruvic acid concentration was exhibited within the range of 0.00014-0.001 mol l(-1), and the pyruvic acid detection limit was found to be 8.537 × 10(-5) mol l(-1). This method was successfully applied to the detection of PA in quail serum with a good recovery of over 70%.

  2. Effects of Eimeria acervulina infection severity on growth performance, apparent ileal amino acid digestibility, and plasma concentrations of amino acids, carotenoids, and α1-acid glycoprotein in broilers.

    PubMed

    Rochell, S J; Parsons, C M; Dilger, R N

    2016-07-01

    An experiment was conducted to evaluate growth performance, apparent ileal digestibility (AID) of amino acids, and plasma concentrations of amino acids, carotenoids, and α1-acid glycoprotein, an acute-phase protein, in broilers inoculated with graded doses of E. acervulina oocysts. Ross 308 male broilers (400 total) were housed in battery cages from 1 to 21 d post-hatch and received common corn-soybean meal-based diets throughout the experiment. At 9 d post-hatch, birds were individually weighed and allotted to 4 treatment groups with 10 replicate cages of 10 birds per cage. At 15 d post-hatch, all birds were inoculated with 1 mL of distilled water that contained 0, 2.5 × 10(5), 5.0 × 10(5), or 1.0 × 10(6) sporulated E. acervulina oocysts. At 21 d, birds were euthanized for collection of blood and ileal digesta. Body weight gain and feed efficiency decreased linearly (P < 0.05) with increasing E. acervulina dose. With the exception of Trp and Gly, AID values decreased (P < 0.05) linearly or quadratically for all amino acids by an average of 2.6 percentage units for birds inoculated with 1.0 × 10(6) oocysts compared with uninfected birds. Infection with E. acervulina caused a quadratic decrease (P < 0.05) in plasma carotenoid concentrations. Plasma concentrations of Arg and Tyr decreased linearly (P < 0.05) with increasing E. acervulina inoculation dose and plasma Gln and Asn decreased quadratically (P < 0.01). Linear increases (P < 0.05) were observed for plasma Lys, Leu, Ile, Val, Pro, and Orn as E. acervulina inoculation dose increased. Plasma α1-acid glycoprotein of broilers was not influenced (P > 0.05) by E. acervulina infection. In conclusion, E. acervulina challenge adversely impacted growth performance, plasma carotenoids, and AID of amino acids in a dose-dependent manner. However, plasma amino acid responses to graded E. acervulina inoculation doses varied considerably among amino acids. Thus, these results indicated that alterations

  3. Catalytic synthesis of biodiesel from high free fatty acid-containing feedstocks

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recyclable and reusable heterogeneous diarylammonium catalysts are highly effective in catalyzing the esterification of the free fatty acid (FFA) present in greases to methyl esters to reduce the FFA content from 12-40 wt% to 0.5 – 1 wt%. The resulting ester-glyceride mixture (pretreated grease) co...

  4. Functional genomics analysis of free fatty acid production under continuous phosphate limiting conditions.

    PubMed

    Youngquist, J Tyler; Korosh, Travis C; Pfleger, Brian F

    2016-10-13

    Free fatty acids (FFA) are an attractive platform chemical that serves as a functional intermediate in metabolic pathways for producing oleochemicals. Many groups have established strains of Escherichia coli capable of producing various chain-length mixtures of FFA by heterologous expression of acyl-ACP thioesterases. For example, high levels of dodecanoic acid are produced by an E. coli strain expressing the Umbellularia californica FatB2 thioesterase, BTE. Prior studies achieved high dodecanoic acid yields and productivities under phosphate-limiting media conditions. In an effort to understand the metabolic and physiological changes that led to increased FFA production, the transcriptome of this strain was assessed as a function of nutrient limitation and growth rate. FFA generation under phosphate limitation led to consistent changes in transporter expression, osmoregulation, and central metabolism. Guided by these results, targeted knockouts led to a further ~11 % in yield in FFA.

  5. Effect of dimethylamine on the gas phase sulfuric acid concentration measured by Chemical Ionization Mass Spectrometry.

    PubMed

    Rondo, L; Ehrhart, S; Kürten, A; Adamov, A; Bianchi, F; Breitenlechner, M; Duplissy, J; Franchin, A; Dommen, J; Donahue, N M; Dunne, E M; Flagan, R C; Hakala, J; Hansel, A; Keskinen, H; Kim, J; Jokinen, T; Lehtipalo, K; Leiminger, M; Praplan, A; Riccobono, F; Rissanen, M P; Sarnela, N; Schobesberger, S; Simon, M; Sipilä, M; Smith, J N; Tomé, A; Tröstl, J; Tsagkogeorgas, G; Vaattovaara, P; Winkler, P M; Williamson, C; Wimmer, D; Baltensperger, U; Kirkby, J; Kulmala, M; Petäjä, T; Worsnop, D R; Curtius, J

    2016-03-27

    Sulfuric acid is widely recognized as a very important substance driving atmospheric aerosol nucleation. Based on quantum chemical calculations it has been suggested that the quantitative detection of gas phase sulfuric acid (H2SO4) by use of Chemical Ionization Mass Spectrometry (CIMS) could be biased in the presence of gas phase amines such as dimethylamine (DMA). An experiment (CLOUD7 campaign) was set up at the CLOUD (Cosmics Leaving OUtdoor Droplets) chamber to investigate the quantitative detection of H2SO4 in the presence of dimethylamine by CIMS at atmospherically relevant concentrations. For the first time in the CLOUD experiment, the monomer sulfuric acid concentration was measured by a CIMS and by two CI-APi-TOF (Chemical Ionization-Atmospheric Pressure interface-Time Of Flight) mass spectrometers. In addition, neutral sulfuric acid clusters were measured with the CI-APi-TOFs. The CLOUD7 measurements show that in the presence of dimethylamine (<5 to 70 pptv) the sulfuric acid monomer measured by the CIMS represents only a fraction of the total H2SO4, contained in the monomer and the clusters that is available for particle growth. Although it was found that the addition of dimethylamine dramatically changes the H2SO4 cluster distribution compared to binary (H2SO4-H2O) conditions, the CIMS detection efficiency does not seem to depend substantially on whether an individual H2SO4 monomer is clustered with a DMA molecule. The experimental observations are supported by numerical simulations based on A Self-contained Atmospheric chemistry coDe coupled with a molecular process model (Sulfuric Acid Water NUCleation) operated in the kinetic limit.

  6. Effect of dimethylamine on the gas phase sulfuric acid concentration measured by Chemical Ionization Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Rondo, L.; Ehrhart, S.; Kürten, A.; Adamov, A.; Bianchi, F.; Breitenlechner, M.; Duplissy, J.; Franchin, A.; Dommen, J.; Donahue, N. M.; Dunne, E. M.; Flagan, R. C.; Hakala, J.; Hansel, A.; Keskinen, H.; Kim, J.; Jokinen, T.; Lehtipalo, K.; Leiminger, M.; Praplan, A.; Riccobono, F.; Rissanen, M. P.; Sarnela, N.; Schobesberger, S.; Simon, M.; Sipilä, M.; Smith, J. N.; Tomé, A.; Tröstl, J.; Tsagkogeorgas, G.; Vaattovaara, P.; Winkler, P. M.; Williamson, C.; Wimmer, D.; Baltensperger, U.; Kirkby, J.; Kulmala, M.; Petäjä, T.; Worsnop, D. R.; Curtius, J.

    2016-03-01

    Sulfuric acid is widely recognized as a very important substance driving atmospheric aerosol nucleation. Based on quantum chemical calculations it has been suggested that the quantitative detection of gas phase sulfuric acid (H2SO4) by use of Chemical Ionization Mass Spectrometry (CIMS) could be biased in the presence of gas phase amines such as dimethylamine (DMA). An experiment (CLOUD7 campaign) was set up at the CLOUD (Cosmics Leaving OUtdoor Droplets) chamber to investigate the quantitative detection of H2SO4 in the presence of dimethylamine by CIMS at atmospherically relevant concentrations. For the first time in the CLOUD experiment, the monomer sulfuric acid concentration was measured by a CIMS and by two CI-APi-TOF (Chemical Ionization-Atmospheric Pressure interface-Time Of Flight) mass spectrometers. In addition, neutral sulfuric acid clusters were measured with the CI-APi-TOFs. The CLOUD7 measurements show that in the presence of dimethylamine (<5 to 70 pptv) the sulfuric acid monomer measured by the CIMS represents only a fraction of the total H2SO4, contained in the monomer and the clusters that is available for particle growth. Although it was found that the addition of dimethylamine dramatically changes the H2SO4 cluster distribution compared to binary (H2SO4-H2O) conditions, the CIMS detection efficiency does not seem to depend substantially on whether an individual H2SO4 monomer is clustered with a DMA molecule. The experimental observations are supported by numerical simulations based on A Self-contained Atmospheric chemistry coDe coupled with a molecular process model (Sulfuric Acid Water NUCleation) operated in the kinetic limit.

  7. Effect of dimethylamine on the gas phase sulfuric acid concentration measured by Chemical Ionization Mass Spectrometry

    PubMed Central

    Ehrhart, S.; Kürten, A.; Adamov, A.; Bianchi, F.; Breitenlechner, M.; Duplissy, J.; Franchin, A.; Dommen, J.; Donahue, N. M.; Dunne, E. M.; Flagan, R. C.; Hakala, J.; Hansel, A.; Keskinen, H.; Kim, J.; Jokinen, T.; Lehtipalo, K.; Leiminger, M.; Praplan, A.; Riccobono, F.; Rissanen, M. P.; Sarnela, N.; Schobesberger, S.; Simon, M.; Sipilä, M.; Smith, J. N.; Tomé, A.; Tröstl, J.; Tsagkogeorgas, G.; Vaattovaara, P.; Winkler, P. M.; Williamson, C.; Wimmer, D.; Baltensperger, U.; Kirkby, J.; Kulmala, M.; Petäjä, T.; Worsnop, D. R.; Curtius, J.

    2016-01-01

    Abstract Sulfuric acid is widely recognized as a very important substance driving atmospheric aerosol nucleation. Based on quantum chemical calculations it has been suggested that the quantitative detection of gas phase sulfuric acid (H2SO4) by use of Chemical Ionization Mass Spectrometry (CIMS) could be biased in the presence of gas phase amines such as dimethylamine (DMA). An experiment (CLOUD7 campaign) was set up at the CLOUD (Cosmics Leaving OUtdoor Droplets) chamber to investigate the quantitative detection of H2SO4 in the presence of dimethylamine by CIMS at atmospherically relevant concentrations. For the first time in the CLOUD experiment, the monomer sulfuric acid concentration was measured by a CIMS and by two CI‐APi‐TOF (Chemical Ionization‐Atmospheric Pressure interface‐Time Of Flight) mass spectrometers. In addition, neutral sulfuric acid clusters were measured with the CI‐APi‐TOFs. The CLOUD7 measurements show that in the presence of dimethylamine (<5 to 70 pptv) the sulfuric acid monomer measured by the CIMS represents only a fraction of the total H2SO4, contained in the monomer and the clusters that is available for particle growth. Although it was found that the addition of dimethylamine dramatically changes the H2SO4 cluster distribution compared to binary (H2SO4‐H2O) conditions, the CIMS detection efficiency does not seem to depend substantially on whether an individual H2SO4 monomer is clustered with a DMA molecule. The experimental observations are supported by numerical simulations based on A Self‐contained Atmospheric chemistry coDe coupled with a molecular process model (Sulfuric Acid Water NUCleation) operated in the kinetic limit. PMID:27610289

  8. Fatty acid concentration, proximate composition, and mineral composition in fishbone flour of Nile Tilapia.

    PubMed

    Petenuci, Maria Eugênia; Stevanato, Flávia Braidoti; Visentainer, Jeane Eliete Laguila; Matsushita, Makoto; Garcia, Edivaldo Egea; de Souza, Nilson Evelázio; Visentainer, Jesui Vergilio

    2008-03-01

    Nile tilapia (Oreochormis niloticus) fishbone is a fish part with unknown composition. After elaboration of flour fishbone of tilapia it was analysede. The results in 100 g of flour were: moisture (14.2%), protein (40.8%), total lipids (25.3%), and ash (18.3%), and mineral (in 100 g) was 2715.9 mg (calcium), 1.3 mg (iron), and 1132.7 mg (phosphorus). A total of 22 fatty acids were detected in fishbone flour total lipids (TL), being the major ones in (g) of total lipids: 16:0 (208.5 mg); 18:1n-9 (344.3 mg); and 18:2n-6 (109.6 mg). The concentration of linolenic acid--LNA (18:3n-3); eicopentaenoic acid--EPA (20:5n-3), and docosahexaenoic acid--DHA (22:6n-3) were (29.9 mg), (3.3 mg), and (12.9 mg), respectively. The content to saturated (SFA) were (296.2 mg), monounsaturated (MUFA) 415.0 mg, and polyunsaturated (PUFA) 175.6 mg. The ratio PUFA:MUFA:SFA was 1:2.4:1.7, and the ratio omega-6/omega-3 fatty acids were 2.8. The last is within the recommended values. The results show low concentrations of omega-3 fatty acids in flour. The value caloric and calcium, iron, phosphorus, and protein content the fishbone flour of tilapia may results a valuable alternative food in the human diet.

  9. Frontal Gamma-Aminobutyric Acid Concentrations Are Associated With Cognitive Performance in Older Adults

    PubMed Central

    Porges, Eric C.; Woods, Adam J.; Edden, Richard A.E.; Puts, Nicolaas A.J.; Harris, Ashley D.; Chen, Huaihou; Garcia, Amanda M.; Seider, Talia R.; Lamb, Damon G.; Williamson, John B.; Cohen, Ronald A.

    2017-01-01

    BACKGROUND Gamma-aminobutyric acid (GABA), the brain’s principal inhibitory neurotransmitter, has been associated with perceptual and attentional functioning. Recent application of magnetic resonance spectroscopy (MRS) provides in vivo evidence for decreasing GABA concentrations during adulthood. It is unclear, however, how age-related decrements in cerebral GABA concentrations contribute to cognitive decline, or whether previously reported declines in cerebral GABA concentrations persist during healthy aging. We hypothesized that participants with higher GABA concentrations in the frontal cortex would exhibit superior cognitive function and that previously reported age-related decreases in cortical GABA concentrations continue into old age. METHODS We measured GABA concentrations in frontal and posterior midline cerebral regions using a Mescher-Garwood point-resolved spectroscopy (MEGA-PRESS) 1H-MRS approach in 94 older adults without history or clinical evidence of mild cognitive impairment or dementia (mean age, 73 years). We administered the Montreal Cognitive Assessment to assess cognitive functioning. RESULTS Greater frontal GABA concentrations were associated with superior cognitive performance. This relation remained significant after controlling for age, years of education, and brain atrophy. GABA concentrations in both frontal and posterior regions decreased as a function of age. CONCLUSIONS These novel findings from a large, healthy, older population indicate that cognitive function is sensitive to cerebral GABA concentrations in the frontal cortex, and GABA concentration in frontal and posterior regions continue to decline in later age. These effects suggest that proton MRS may provide a clinically useful method for the assessment of normal and abnormal age-related cognitive changes and the associated physiological contributors. PMID:28217759

  10. The effects of allopurinol, uric acid, and inosine administration on xanthine oxidoreductase activity and uric acid concentrations in broilers.

    PubMed

    Settle, T; Carro, M D; Falkenstein, E; Radke, W; Klandorf, H

    2012-11-01

    The purpose of these studies was to determine the effects of uric acid (UA) and inosine administration on xanthine oxidoreductase activity in broilers. In experiment one, 25 broilers were assigned to 5 treatment groups: control, AL (25 mg of allopurinol/kg of body mass), AR (AL for 2 wk followed by allopurinol withdrawal over wk 3), UAF (AL plus 6.25 g of UA sodium salt/kg of feed), and UAI (AL plus 120 mg of UA sodium salt injected daily). The UA administration had no effect on plasma concentration of UA (P > 0.05), and all allopurinol-treated birds had lower (P < 0.05) UA levels than controls. The UA concentrations were restored in both plasma and kidney of AR birds at wk 3, but liver UA concentrations remained lower. Whereas xanthine oxidoreductase (XOR) activity in the liver (LXOR) was reduced (P < 0.05) by allopurinol treatment, XOR activity in the kidney (KXOR) was not affected (P = 0.05). In experiment two, 3 groups of 5 birds each were fed 0 (control), 0.6 M inosine/kg of feed (INO), or INO plus 50 mg of allopurinol/kg of body mass (INOAL). The INOAL birds showed lower total LXOR activity, but KXOR activity was not affected. Both INO and INOAL birds had higher plasma and kidney UA concentrations than controls. The results suggest that regulation of UA production is tissue dependent.

  11. Evaluation of the morphological changes of gastric mucosa induced by a low concentration of acetic acid using a rat model.

    PubMed

    Nakao, Ken-ichiro; Ro, Ayako; Kibayashi, Kazuhiko

    2014-02-01

    Oral ingestion of concentrated acetic acid causes corrosive injury of the gastrointestinal tract. To assess the effects of a low concentration of acetic acid on gastric mucosa, we examined the gastric mucosal changes in rats at 1 and 3 days after the injection of 5% or 25% acetic acid into the gastric lumen. The area of the gastric ulcerative lesions in the 25% acetic acid group was significantly larger than that in the 5% acetic acid group. The lesion area was reduced significantly at 3 days after injection in the 5% acetic acid group, whereas no significant difference in lesion area was observed at 1 and 3 days in the 25% acetic acid group. Histologically, corrosive necrosis was limited to the mucosal layer in the 5% acetic acid group, whereas necrosis extended throughout the gastric wall in the 25% acetic acid group. At 3 days post-injection, the 25% acetic acid group showed widespread persistent inflammation, whereas the 5% acetic acid group showed widespread appearance of fibroblasts indicative of a healing process. These results indicate that a low concentration of acetic acid damages the gastric mucosa and that the degree of mucosal damage depends on the concentration of acetic acid.

  12. Determination of free fatty acids and triglycerides by gas chromatography using selective esterification reactions.

    PubMed

    Kail, Brian W; Link, Dirk D; Morreale, Bryan D

    2012-01-01

    A method for selectively determining both free fatty acids (FFA) and triacylglycerides (TAGs) in biological oils was investigated and optimized using gas chromatography after esterification of the target species to their corresponding fatty acid methyl esters (FAMEs). The method used acid catalyzed esterification in methanolic solutions under conditions of varying severity to achieve complete conversion of more reactive FFAs while preserving the concentration of TAGs. Complete conversion of both free acids and glycerides to corresponding FAMEs was found to require more rigorous reaction conditions involving heating to 120°C for up to 2 h. Method validation was provided using gas chromatography-flame ionization detection, gas chromatography-mass spectrometry, and liquid chromatography-mass spectrometry. The method improves on existing methods because it allows the total esterified lipid to be broken down by FAMEs contributed by FFA compared to FAMEs from both FFA and TAGs. Single and mixed-component solutions of pure fatty acids and triglycerides, as well as a sesame oil sample to simulate a complex biological oil, were used to optimize the methodologies. Key parameters that were investigated included: HCl-to-oil ratio, temperature and reaction time. Pure free fatty acids were found to esterify under reasonably mild conditions (10 min at 50°C with a 2.1:1 HCl to fatty acid ratio) with 97.6 ± 2.3% recovery as FAMEs, while triglycerides were largely unaffected under these reaction conditions. The optimized protocol demonstrated that it is possible to use esterification reactions to selectively determine the free acid content, total lipid content, and hence, glyceride content in biological oils. This protocol also allows gas chromatography analysis of FAMEs as a more ideal analyte than glyceride species in their native state.

  13. Determination of Free Fatty Acids and Triglycerides by Gas Chromatography Using Selective Esterification Reactions

    SciTech Connect

    Kail, Brian W; Link, Dirk D; Morreale, Bryan D

    2012-11-01

    A method for selectively determining both free fatty acids (FFA) and triacylglycerides (TAGs) in biological oils was investigated and optimized using gas chromatography after esterification of the target species to their corresponding fatty acid methyl esters (FAMEs). The method used acid catalyzed esterification in methanolic solutions under conditions of varying severity to achieve complete conversion of more reactive FFAs while preserving the concentration of TAGs. Complete conversion of both free acids and glycerides to corresponding FAMEs was found to require more rigorous reaction conditions involving heating to 120°C for up to 2 h. Method validation was provided using gas chromatography–flame ionization detection, gas chromatography–mass spectrometry, and liquid chromatography–mass spectrometry. The method improves on existing methods because it allows the total esterified lipid to be broken down by FAMEs contributed by FFA compared to FAMEs from both FFA and TAGs. Single and mixed-component solutions of pure fatty acids and triglycerides, as well as a sesame oil sample to simulate a complex biological oil, were used to optimize the methodologies. Key parameters that were investigated included: HCl-to-oil ratio, temperature and reaction time. Pure free fatty acids were found to esterify under reasonably mild conditions (10 min at 50°C with a 2.1:1 HCl to fatty acid ratio) with 97.6 ± 2.3% recovery as FAMEs, while triglycerides were largely unaffected under these reaction conditions. The optimized protocol demonstrated that it is possible to use esterification reactions to selectively determine the free acid content, total lipid content, and hence, glyceride content in biological oils. This protocol also allows gas chromatography analysis of FAMEs as a more ideal analyte than glyceride species in their native state.

  14. Concentrations of retinol and tocopherols in the milk of cows supplemented with conjugated linoleic acid.

    PubMed

    Gessner, D K; Most, E; Schlegel, G; Kupczyk, K; Schwarz, F J; Eder, K

    2015-12-01

    This study was performed to investigate the hypothesis that supplementation of conjugated linoleic acid (CLA) changes the concentrations of retinol and tocopherols in the milk of cows. To investigate this hypothesis, Holstein cows received daily from 3 weeks ante-partum to 14 weeks post-partum either 172 g of a CLA-free rumen-protected control fat (control group, n = 20) or the same amount of a rumen-protected CLA fat, supplying 4.3 g of cis-9, trans-11 CLA and 3.8 g of trans-10, cis-12 CLA per d (CLA group, n = 20). Milk samples (collected at weeks 1, 3, 5, 8 and 11 of lactation) were analysed for retinol, α- and γ-tocopherol concentrations. Milk of cows supplemented with CLA had higher concentrations of retinol (+34%), α-tocopherol (+44%) and γ-tocopherol (+21%) than milk of control cows (p < 0.05). The daily output of these vitamins via milk was also greater in cows of the CLA group than in cows of the control group (+36, 50 and 24% for retinol, α-tocopherol and γ-tocopherol, respectively, p < 0.05). In agreement with higher concentrations of tocopherols, concentrations of thiobarbituric acid-reactive substances, determined in milk of week 5, were lower in cows of the CLA group than in control cows, indicative of a lower susceptibility of milk lipids to peroxidation. Plasma concentrations of retinol and α-tocopherol, determined at 1 and 5 weeks post-partum, were not different between the two groups of cows. In conclusion, this study shows that supplementing dairy cows with a moderate amount of CLA causes an increase of the concentrations of vitamins A and E in the milk and results in an increased output of those vitamins via milk. These effects might be beneficial with respect to the nutritional value of dairy products and the susceptibility of milk fat to oxidative deterioration.

  15. Influence of H 2SO 4 concentration on the performance of lead-acid battery negative plates

    NASA Astrophysics Data System (ADS)

    Pavlov, D.; Petkova, G.; Rogachev, T.

    The influence of sulfuric acid concentration on negative plate performance has been studied on 12 V/32 Ah lead-acid batteries with three negative and four positive plates per cell, i.e. the negative active material limits battery capacity. Initial capacity tests, including C20 capacity, cold cranking ability and Peukert tests, have been carried out in a wide range of sulfuric acid concentrations (from 1.18 to 1.33 sp.gr.). High initial capacity and good CCA performance were registered for batteries with acid concentration between 1.24 and 1.30 sp.gr. The charge acceptance depends on acid concentration as well as on battery state of charge. Batteries with high SoC exhibit high charge acceptance at low acid concentrations. The cycle life tests at two discharge rates (10 and 3 h discharge) evidence that sulfuric acid concentration exerts a strong effect on negative plate performance. The cycle life of batteries decreases with increase of acid concentration. The obtained results demonstrate the high impact of lead sulfate solubility on the cycle life and charge efficiency of lead-acid batteries.

  16. A method for concentrating organic dyes: colorimetric measurements of nitric oxides and sialic acids.

    PubMed

    Lalezari, Parviz; Lekhraj, Rukmani; Casper, Diana

    2011-09-01

    A new method for extraction and concentration of organic dyes that uses a reagent composed of a nonionic detergent mixed with an alcohol is described. We have observed that water-soluble organic dyes are also soluble in nonionic detergents and can be extracted by adding salt, which separates the dye-detergent component from the aqueous phase. We have also found that mixing nonionic detergents with alcohols markedly reduces their viscosity and produces stable, free-flowing, and effective reagents for color extraction. On the basis of these observations, we used a mixture of Triton X-100 and 1-butanol and observed that water-soluble natural and synthetic chromophores, as well as dyes generated in biochemical reactions, can be extracted, concentrated, and analyzed spectrophotometrically. Trypan blue and phenol red are used as examples of synthetic dyes, and red wine is used as an example of phenolic plant pigments. Applications for quantification of nitric oxides and sialic acids are described in more detail and show that as little as 0.15 nmol of nitric oxide and 0.20 nmol of sialic acid can be detected. A major advantage of this method is its ability to concentrate chromophores from dye-containing solutions that otherwise cannot be measured because of their low concentrations.

  17. nC60 deposition kinetics: the complex contribution of humic acid, ion concentration, and valence.

    PubMed

    McNew, Coy P; LeBoeuf, Eugene J

    2016-07-01

    The demonstrated toxicity coupled with inevitable environmental release of nC60 raise serious concerns about its environmental fate and transport, therefore it is crucial to understand how nC60 will interact with subsurface materials including attached phase soil and sediment organic matter (AP-SOM). This study investigated the attachment of nC60 onto a Harpeth humic acid (HHA) coated silica surface under various solution conditions using a quartz crystal microbalance with dissipation monitoring. The HHA coating greatly enhanced nC60 attachment at low ion concentrations while hindering attachment at high ion concentrations in the presence of both mono and divalent cations. At low ion concentrations, the HHA greatly reduced the surface potential of the silica, enhancing nC60 deposition through reduction in the electrostatic repulsion. At high ion concentrations however, the reduced surface potential became less important due to the near zero energy barrier to deposition and therefore non-DLVO forces dominated, induced by compaction of the HHA layer, and leading to hindered attachment. In this manner, observed contributions from the HHA layer were more complex than previously reported and by monitoring surface charge and calculated DLVO interaction energy alongside attachment experiments, this study advances the mechanistic understanding of the variable attachment contributions from the humic acid layer.

  18. Influence of HF acid catalyst concentration on properties of aerogel low-k thin films

    NASA Astrophysics Data System (ADS)

    Gaikwad, A. S.; Gupta, S. A.; Mahajan, A. M.

    2016-08-01

    The effect of hydrofluoric acid (HF) catalyst concentration in coating solution on chemical, physical and structural properties of silica aerogel thin films was investigated. The aerogel films were synthesized by using a sol-gel spin coating method followed by aging in ethanol and CO2 supercritical drying. The refractive index (RI) is observed to be reduced from 1.32 to 1.13 and porosity percentage increased from 30.21% to 71.64% in accordance with increasing HF concentration. Deposition of silica aerogel was confirmed from Fourier transform infrared spectroscopy measurement. The nanoporous nature of deposited films was confirmed from field effect scanning electron microscopy and observed pore diameter is in the range of 3.33 to 6.69 nm. The nanoporous nature of the film was also validated from atomic force microscopy and root mean square roughness was observed to be increased from 2.31 nm to 3.2 nm with increasing acid catalyst concentration in the coating solution. The calculated dielectric constant from CV measurement of fabricated metal-insulator-semiconductor structure for the silica aerogel formed at 0.8 ml HF concentration is observed to be 1.73. These deposited nanoporous silica aerogel low-k films with lower k value and smaller pore size have application as interlayer dielectric materials to minimize the disadvantages of porous materials.

  19. The effect of convalescent meridian acupressure after exercise on stress hormones and lactic acid concentration changes

    PubMed Central

    Shin, Won

    2013-01-01

    Meridian acupressure has been used as the one way recovering body conditions. The purpose of this study was to investigate whether meridian acupressure is effective on removing cortisol, norepinephrine, epinephrine, and lactic acid in blood following exercise. The subjects were 12 healthy male college students and data were processed using SPSS 12.0 statistical program and the results were calculated by setting the significance level at P< 0.05. First, there was a significant difference between exercise recovery group except for stability group and acupressure recovery group in convalescent cortisol concentration changes after exercise (P= 0.001). And acupressure recovery group showed a significant difference compared with two groups (P= 0.001). Second, exercise recovery group showed nonsignificant difference in convalescent norepinephrine concentration changes but meridian acupressure recovery group showed a significant difference (P= 0.001). There was a significance difference in the groups rather than exercise recovery group and rest recovery group (P= 0.001). Third, exercise recovery group and acupressure recovery group showed a significant difference in convalescent epinephrine concentration changes after exercise (P= 0.001). However, rest recovery group showed nonsignificant difference. In addition, three groups showed nonsignificant difference in the groups. However, it showed in order of acupressure= exercise> rest recovery. Fourth, three groups showed a significant difference in convalescent lactic acid concentration changes after exercise (P = 0.001). And it showed in order of acupressure= exercise> rest recovery after recovery treatment in the groups (P= 0.001). PMID:24278880

  20. Safflower oil consumption does not increase plasma conjugated linoleic acid concentrations in humans.

    PubMed

    Herbel, B K; McGuire, M K; McGuire, M A; Shultz, T D

    1998-02-01

    Conjugated linoleic acid (CLA) is a mixture of positional and geometric isomers of linoleic acid (LA) with conjugated double bonds. CLA has anticarcinogenic properties and has been identified in human tissues, dairy products, meats, and certain vegetable oils. A variety of animal products are good sources of CLA, but plant oils contain much less. However, plant oils are a rich source of LA, which may be isomerized to CLA by intestinal microorganisms in humans. To investigate the effect of triacylglycerol-esterified LA consumption on plasma concentrations of esterified CLA in total lipids, a dietary intervention (6 wk) was conducted with six men and six women. During the intervention period a salad dressing containing 21 g safflower oil providing 16 g LA/d was added to the subjects' daily diets. Three-day diet records and fasting blood were obtained initially and during dietary and postdietary intervention periods. Although LA intake increased significantly during the dietary intervention, plasma CLA concentrations were not affected. Plasma total cholesterol and LDL-cholesterol concentrations were significantly lower after addition of safflower oil to the diet. In summary, consumption of triacylglycerol-esterified LA in safflower oil did not increase plasma concentrations of esterified CLA in total lipids.

  1. Intrashell variations in amino acid concentrations and isoleucine epimerization ratios in fossil Hiatella arctica

    NASA Astrophysics Data System (ADS)

    Brigham, Julie K.

    1983-09-01

    Twenty-four valves of fossil Hiatella arctica were analyzed to determine if amino acid ratios varied from one region of a shell to another. The ratio of D-alloisoleucine/L-isoleucine, routinely used as a stratigraphic correlation tool and an indicator of relative age, did not vary significantly between five anatomically different shell parts in Hiatella arctica. Sampling only the hinge or central part of all valves, however, resulted in less variation about the average value. Analyses of only this part of the shell should improve the resolution of stratigraphic units by amino acid geochronology. The absolute concentrations of aspartic acid, threonine, serine, glutamic acid, glycine, alanine, valine, alloisoleucine, isoleucine, and leucine (in picomoles/milligram of shell) are significantly higher in the hinge and central part of the shell, whereas the outer growth edge appears to have lower levels of amino acids. This is true in both the FREE and TOTAL hydrolysate fractions. The reasons are not clear; however, the high value may be caused by a thin, protein-rich inner layer lining the valve out to the pallial line and/or differences in the proportion of inorganic carbonate to protein produced in different areas during shell growth. Alternatively, it may suggest leaching of the thinner, more vulnerable part of the shell growth edge.

  2. Reduced gamma-aminobutyric acid concentration is associated with physical disability in progressive multiple sclerosis.

    PubMed

    Cawley, Niamh; Solanky, Bhavana S; Muhlert, Nils; Tur, Carmen; Edden, Richard A E; Wheeler-Kingshott, Claudia A M; Miller, David H; Thompson, Alan J; Ciccarelli, Olga

    2015-09-01

    Neurodegeneration is thought to be the major cause of ongoing, irreversible disability in progressive stages of multiple sclerosis. Gamma-aminobutyric acid is the principle inhibitory neurotransmitter in the brain. The aims of this study were to investigate if gamma-aminobutyric acid levels (i) are abnormal in patients with secondary progressive multiple sclerosis compared with healthy controls; and (ii) correlate with physical and cognitive performance in this patient population. Thirty patients with secondary progressive multiple sclerosis and 17 healthy control subjects underwent single-voxel MEGA-PRESS (MEscher-GArwood Point RESolved Spectroscopy) magnetic resonance spectroscopy at 3 T, to quantify gamma-aminobutyric acid levels in the prefrontal cortex, right hippocampus and left sensorimotor cortex. All subjects were assessed clinically and underwent a cognitive assessment. Multiple linear regression models were used to compare differences in gamma-aminobutyric acid concentrations between patients and controls adjusting for age, gender and tissue fractions within each spectroscopic voxel. Regression was used to examine the relationships between the cognitive function and physical disability scores specific for these regions with gamma-aminobuytric acid levels, adjusting for age, gender, and total N-acetyl-aspartate and glutamine-glutamate complex levels. When compared with controls, patients performed significantly worse on all motor and sensory tests, and were cognitively impaired in processing speed and verbal memory. Patients had significantly lower gamma-aminobutyric acid levels in the hippocampus (adjusted difference = -0.403 mM, 95% confidence intervals -0.792, -0.014, P = 0.043) and sensorimotor cortex (adjusted difference = -0.385 mM, 95% confidence intervals -0.667, -0.104, P = 0.009) compared with controls. In patients, reduced motor function in the right upper and lower limb was associated with lower gamma-aminobutyric acid concentration in the

  3. Effects of different vegetable oils on rumen fermentation and conjugated linoleic acid concentration in vitro

    PubMed Central

    Roy, Amitava; Mandal, Guru Prasad; Patra, Amlan Kumar

    2017-01-01

    Aim: The objective of this study was to investigate the effect of different vegetable oils on rumen fermentation and concentrations of beneficial cis-9 trans-11 C18:2 conjugated linoleic acid (CLA) and trans-11 C18:1 fatty acid (FA) in the rumen fluid in an in vitro condition. Materials and Methods: Six vegetable oils including sunflower, soybean, sesame, rice bran, groundnut, and mustard oils were used at three dose levels (0%, 3% and 4% of substrate dry matter [DM] basis) in three replicates for each treatment in a completely randomized design using 6 × 3 factorial arrangement. Rumen fluid for microbial culture was collected from four goats fed on a diet of concentrate mixture and berseem hay at a ratio of 60:40 on DM basis. The in vitro fermentation was performed in 100 ml conical flakes containing 50 ml of culture media and 0.5 g of substrates containing 0%, 3% and 4% vegetable oils. Results: Oils supplementation did not affect (p>0.05) in vitro DM digestibility, and concentrations of total volatile FAs and ammonia-N. Sunflower oil and soybean oil decreased (p<0.05) protozoal numbers with increasing levels of oils. Other oils had less pronounced effect (p>0.05) on protozoal numbers. Both trans-11 C18:1 FA and cis-9, trans-11 CLA concentrations were increased (p<0.05) by sunflower and soybean oil supplementation at 4% level with the highest concentration observed for sunflower oil. The addition of other oils did not significantly (p>0.05) increase the trans-11 C18:1 FA and cis-9, trans-11 CLA concentrations as compared to the control. The concentrations of stearic, oleic, linoleic, and linolenic acids were not altered (p>0.05) due to the addition of any vegetable oils. Conclusion: Supplementation of sunflower and soybean oils enhanced beneficial trans-11 C18:1 FA and cis-9, trans-11 CLA concentrations in rumen fluid, while sesame, rice bran, groundnut, and mustard oils were ineffective in this study. PMID:28246442

  4. Salicylhydroxamic acid (SHAM) inhibition of the dissolved inorganic carbon concentrating process in unicellular green algae

    SciTech Connect

    Goyal, A.; Tolbert, N.E. )

    1990-03-01

    Rates of photosynthetic O{sub 2} evolution, for measuring K{sub 0.5}(CO{sub 2} + HCO{sub 3}{sup {minus}}) at pH 7, upon addition of 50 micromolar HCO{sub 3}{sup {minus}} to air-adapted Chlamydomonas, Dunaliella, or Scenedesmus cells, were inhibited up to 90% by the addition of 1.5 to 4.0 millimolar salicylhydroxamic acid (SHAM) to the aqueous medium. The apparent K{sub i}(SHAM) for Chlamydomonas cells was about 2.5 millimolar, but due to low solubility in water effective concentrations would be lower. Salicylhydroxamic acid did not inhibit oxygen evolution or accumulation of bicarbonate by Scenedesmus cells between pH 8 to 11 or by isolated intact chloroplasts from Dunaliella. Thus, salicylhydroxamic acid appears to inhibit CO{sub 2} uptake, whereas previous results indicate that vanadate inhibits bicarbonate uptake. These conclusions were confirmed by three test procedures with three air-adapted algae at pH 7. Salicylhydroxamic acid inhibited the cellular accumulation of dissolved inorganic carbon, the rate of photosynthetic O{sub 2} evolution dependent on low levels of dissolved inorganic carbon (50 micromolar NaHCO{sub 3}), and the rate of {sup 14}CO{sub 2} fixation with 100 micromolar ({sup 14}C)HCO{sub 3}{sup {minus}}. Salicylhydroxamic acid inhibition of O{sub 2} evolution and {sup 14}CO{sub 2}-fixation was reversed by higher levels of NaHCO{sub 3}. Thus, salicylhydroxamic acid inhibition was apparently not affecting steps of photosynthesis other than CO{sub 2} accumulation. Although salicylhydroxamic acid is an inhibitor of alternative respiration in algae, it is not known whether the two processes are related.

  5. Effects of dissolved oxygen concentration on biodegradation of 2,4-dichlorophenoxyacetic acid.

    PubMed Central

    Shaler, T A; Klecka, G M

    1986-01-01

    Batch experiments were conducted to examine the effects of dissolved oxygen concentration on the degradation of 2,4-dichlorophenoxyacetic acid (2,4-D) by an enrichment culture of 2,4-D-utilizing bacteria. A modified Monod equation was found to describe the relationship between the specific growth rate and the concentrations of both the organic substrate and dissolved oxygen. Values for the maximum specific growth rate, yield, and Monod coefficient for growth on 2,4-D were 0.09 h-1, 0.14 g/g, and 0.6 mg/liter, respectively. The half-saturation constant for dissolved oxygen was estimated to be 1.2 mg/liter. These results suggest that dissolved oxygen concentrations below 1 mg/liter may be rate limiting for the biodegradation of chlorinated aromatic compounds such as 2,4-D, which have a requirement for molecular oxygen as a cosubstrate for metabolism. PMID:3729394

  6. Heterogeneous photocatalytic degradation of p-toluenesulfonic acid using concentrated solar radiation in slurry photoreactor.

    PubMed

    Kamble, Sanjay P; Sawant, Sudhir B; Pangarkar, Vishwas G

    2007-02-09

    In this work, the photocatalytic degradation (PCD) of p-toluenesulfonic acid (p-TSA) in batch reactor using concentrated solar radiation was investigated. The effect of the various operating parameters such as initial concentration of substrate, catalyst loading, solution pH and types of ions on photocatalytic degradation has been studied in a batch reactor to derive the optimum conditions. The rate of photocatalytic degradation was found to be maximum at the self pH (pH 3.34) of p-TSA. It was also observed that in the presence of anions and cations, the rate of PCD decreases drastically. The kinetics of photocatalytic degradation of p-TSA was studied. The PCD of p-TSA was also carried at these optimized conditions in a bench scale slurry bubble column reactor using concentrated solar radiation.

  7. Predicting the toxicity of sediment-associated trace metals with simultaneously extracted trace metal: Acid-volatile sulfide concentrations and dry weight-normalized concentrations: A critical comparison

    USGS Publications Warehouse

    Long, E.R.; MacDonald, D.D.; Cubbage, J.C.; Ingersoll, C.G.

    1998-01-01

    The relative abilities of sediment concentrations of simultaneously extracted trace metal: acid-volatile sulfide (SEM:AVS) and dry weight- normalized trace metals to correctly predict both toxicity and nontoxicity were compared by analysis of 77 field-collected samples. Relative to the SEM:AVS concentrations, sediment guidelines based upon dry weight-normalized concentrations were equally or slightly more accurate in predicting both nontoxic and toxic results in laboratory tests.

  8. Intestinal Dysbiosis Is Associated with Altered Short-Chain Fatty Acids and Serum-Free Fatty Acids in Systemic Lupus Erythematosus

    PubMed Central

    Rodríguez-Carrio, Javier; López, Patricia; Sánchez, Borja; González, Sonia; Gueimonde, Miguel; Margolles, Abelardo; de los Reyes-Gavilán, Clara G.; Suárez, Ana

    2017-01-01

    Metabolic impairments are a frequent hallmark of systemic lupus erythematosus (SLE). Increased serum levels of free fatty acids (FFA) are commonly found in these patients, although the underlying causes remain elusive. Recently, it has been suggested that factors other than inflammation or clinical features may be involved. The gut microbiota is known to influence the host metabolism, the production of short-chain fatty acids (SCFA) playing a potential role. Taking into account that lupus patients exhibit an intestinal dysbiosis, we wondered whether altered FFA levels may be associated with the intestinal microbial composition in lupus patients. To this aim, total and specific serum FFA levels, fecal SCFA levels, and gut microbiota composition were determined in 21 SLE patients and 25 healthy individuals. The Firmicutes to Bacteroidetes (F/B) ratio was strongly associated with serum FFA levels in healthy controls (HC), even after controlling for confounders. However, this association was not found in lupus patients, where a decreased F/B ratio and increased FFA serum levels were noted. An altered production of SCFA was related to the intestinal dysbiosis in lupus, while SCFA levels paralleled those of serum FFA in HC. Although a different serum FFA profile was not found in SLE, specific FFA showed distinct patterns on a principal component analysis. Immunomodulatory omega-3 FFA were positively correlated to the F/B ratio in HC, but not in SLE. Furthermore, divergent associations were observed for pro- and anti-inflammatory FFA with endothelial activation biomarkers in lupus patients. Overall, these findings support a link between the gut microbial ecology and the host metabolism in the pathological framework of SLE. A potential link between intestinal dysbiosis and surrogate markers of endothelial activation in lupus patients is supported, FFA species having a pivotal role. PMID:28167944

  9. Intestinal Dysbiosis Is Associated with Altered Short-Chain Fatty Acids and Serum-Free Fatty Acids in Systemic Lupus Erythematosus.

    PubMed

    Rodríguez-Carrio, Javier; López, Patricia; Sánchez, Borja; González, Sonia; Gueimonde, Miguel; Margolles, Abelardo; de Los Reyes-Gavilán, Clara G; Suárez, Ana

    2017-01-01

    Metabolic impairments are a frequent hallmark of systemic lupus erythematosus (SLE). Increased serum levels of free fatty acids (FFA) are commonly found in these patients, although the underlying causes remain elusive. Recently, it has been suggested that factors other than inflammation or clinical features may be involved. The gut microbiota is known to influence the host metabolism, the production of short-chain fatty acids (SCFA) playing a potential role. Taking into account that lupus patients exhibit an intestinal dysbiosis, we wondered whether altered FFA levels may be associated with the intestinal microbial composition in lupus patients. To this aim, total and specific serum FFA levels, fecal SCFA levels, and gut microbiota composition were determined in 21 SLE patients and 25 healthy individuals. The Firmicutes to Bacteroidetes (F/B) ratio was strongly associated with serum FFA levels in healthy controls (HC), even after controlling for confounders. However, this association was not found in lupus patients, where a decreased F/B ratio and increased FFA serum levels were noted. An altered production of SCFA was related to the intestinal dysbiosis in lupus, while SCFA levels paralleled those of serum FFA in HC. Although a different serum FFA profile was not found in SLE, specific FFA showed distinct patterns on a principal component analysis. Immunomodulatory omega-3 FFA were positively correlated to the F/B ratio in HC, but not in SLE. Furthermore, divergent associations were observed for pro- and anti-inflammatory FFA with endothelial activation biomarkers in lupus patients. Overall, these findings support a link between the gut microbial ecology and the host metabolism in the pathological framework of SLE. A potential link between intestinal dysbiosis and surrogate markers of endothelial activation in lupus patients is supported, FFA species having a pivotal role.

  10. Effects of total gastrectomy on plasma silicon and amino acid concentrations in men.

    PubMed

    Tatara, Marcin R; Krupski, Witold; Szpetnar, Maria; Dąbrowski, Andrzej; Bury, Paweł; Szabelska, Anna; Charuta, Anna; Boguszewska-Czubara, Anna; Maciejewski, Ryszard; Wallner, Grzegorz

    2015-12-01

    The aim of the study was to determine one-year effects of total gastrectomy on plasma silicon and free amino acid concentrations in patients and evaluate changes of volumetric bone mineral density (vBMD) in lumbar spine. Eight patients were enrolled to the control (CTR) group. Six patients subjected to total gastrectomy (GX group) were included to the experimental group. vBMD in trabecular and cortical bone was measured in lumbar vertebrae at baseline (before surgery) and one year later using quantitative computed tomography. Plasma concentrations of silicon and free amino acids were determined at baseline and one year later using photometric method and ion-exchange chromatography. Body weights within CTR and GX groups were not different after one-year follow-up when compared to the baseline values (P > 0.05). An average annual decrease of vBMD in the trabecular bone in the gastrectomized patients reached 15.0% in lumbar spine and was significantly different in comparison to the percentage changes observed in CTR group (P = 0.02). One-year percentage change of vBMD in the cortical bone in L1 and L2 has shown significantly decreased values by 10.5 and 9.1% in the GX group when compared to the percentage change observed in the controls (P < 0.05). Plasma concentration of adipic acid was significantly higher by 101.6% one year after total gastrectomy procedure in the patients when compared to the baseline value (P = 0.01). Plasma concentration of silicon was significantly lowered by 26.7% one year after the total gastrectomy when compared to the baseline value (P = 0.009). Total gastrectomy in patients has induced severe osteoporotic changes in lumbar spine within one-year period. The observed osteoporotic changes were associated with decreased plasma concentration of silicon indicating importance of exocrine and endocrine functions of stomach for silicon homeostasis maintenance. Gastrectomy-induced bone loss was not related to decreased amino acid

  11. Asymmetric synthesis of aromatic β-amino acids using ω-transaminase: Optimizing the lipase concentration to obtain thermodynamically unstable β-keto acids.

    PubMed

    Mathew, Sam; Jeong, Seong-Su; Chung, Taeowan; Lee, Sang-Hyeup; Yun, Hyungdon

    2016-01-01

    Synthesized aromatic β-amino acids have recently attracted considerable attention for their application as precursors in many pharmacologically relevant compounds. Previous studies on asymmetric synthesis of aromatic β-amino acids using ω-transaminases could not be done efficiently due to the instability of β-keto acids. In this study, a strategy to circumvent the instability problem of β-keto acids was utilized to generate β-amino acids efficiently via asymmetric synthesis. In this work, thermodynamically stable β-ketoesters were initially converted to β-keto acids using lipase, and the β-keto acids were subsequently aminated using ω-transaminase. By optimizing the lipase concentration, we successfully overcame the instability problem of β-keto acids and enhanced the production of β-amino acids. This strategy can be used as a general approach to efficiently generate β-amino acids from β-ketoesters.

  12. Free Fatty Acid Receptors and Cancer: From Nutrition to Pharmacology.

    PubMed

    Hopkins, Mandi M; Meier, Kathryn E

    2017-01-01

    The effects of fatty acids on cancer cells have been studied for decades. The roles of dietary long-chain n-3 polyunsaturated fatty acids, and of microbiome-generated short-chain butyric acid, have been of particular interest over the years. However, the roles of free fatty acid receptors (FFARs) in mediating effects of fatty acids in tumor cells have only recently been examined. In reviewing the literature, the data obtained to date indicate that the long-chain FFARs (FFA1 and FFA4) play different roles than the short-chain FFARs (FFA2 and FFA3). Moreover, FFA1 and FFA4 can in some cases mediate opposing actions in the same cell type. Another conclusion is that different types of cancer cells respond differently to FFAR activation. Currently, the best-studied models are prostate, breast, and colon cancer. FFA1 and FFA4 agonists can inhibit proliferation and migration of prostate and breast cancer cells, but enhance growth of colon cancer cells. In contrast, FFA2 activation can in some cases inhibit proliferation of colon cancer cells. Although the available data are sometimes contradictory, there are several examples in which FFAR agonists inhibit proliferation of cancer cells. This is a unique response to GPCR activation that will benefit from a mechanistic explanation as the field progresses. The development of more selective FFAR agonists and antagonists, combined with gene knockout approaches, will be important for unraveling FFAR-mediated inhibitory effects. These inhibitory actions, mediated by druggable GPCRs, hold promise for cancer prevention and/or therapy.

  13. Fatty Acid and Cholesterol Concentrations in Usually Consumed Fish in Brazil

    PubMed Central

    Scherr, Carlos; Gagliardi, Ana Carolina Moron; Miname, Marcio Hiroshi; Santos, Raul Dias

    2015-01-01

    Background Several studies have demonstrated clinical benefits of fish consumption for the cardiovascular system. These effects are attributed to the increased amounts of polyunsaturated fatty acids in these foods. However, the concentrations of fatty acids may vary according to region. Objective The goal of this study was to determine the amount of,cholesterol and fatty acids in 10 Brazilian fishes and in a non-native farmed salmon usually consumed in Brazil. Methods The concentrations of cholesterol and fatty acids, especially omega-3, were determined in grilled fishes. Each fish sample was divided in 3 sub-samples (chops) and each one was extracted from the fish to minimize possible differences in muscle and fat contents. Results The largest cholesterol amount was found in white grouper (107.6 mg/100 g of fish) and the smallest in badejo (70 mg/100 g). Omega-3 amount varied from 0.01 g/100 g in badejo to 0.900 g/100 g in weakfish. Saturated fat varied from 0.687 g/100 g in seabass to 4.530 g/100 g in filhote. The salmon had the greatest concentration of polyunsaturated fats (3.29 g/100 g) and the highest content of monounsaturated was found in pescadinha (5.98 g/100 g). Whiting and boyfriend had the best omega-6/omega 3 ratios respectively 2.22 and 1.19, however these species showed very little amounts of omega-3. Conclusion All studied Brazilian fishes and imported salmon have low amounts of saturated fat and most of them also have low amounts of omega-3. PMID:25424160

  14. [The ultrafiltration at pre-analytical stage under detection of concentration of lactic acid in blood plasma].

    PubMed

    Alekseevskaia, E S; Zhloba, A A; Subbotina, T F

    2013-11-01

    The detection of concentration of lactic acid in blood plasma and other objects is especially applied to discover the mitochondria dysfunctions. The study was organized to analyze samplings of blood plasma and plasma ultra-filtrates taken from 80 healthy persons and 73 patients with activation of intravascular coagulation and fibrinolysis using lactate-oxidase test. The comparative analysis of results of detection of concentrations of lactic acid in blood plasma and its ultra-filtrate established that in 72% of cases the higher values of concentration of detecting lactic acid took place after procedure of ultra-filtration enabling separation of overwhelming quantity of protein. In accordance with accumulated experience in the field of clinical diagnostic practice the enzyme tests are to be applied to detect the concentration of lactic acid in blood plasma and other objects. The present study demonstrated the expediency of application of plasma ultra-filtrate to detect the concentration of lactic acid.

  15. Change in the plasmid copy number in acetic acid bacteria in response to growth phase and acetic acid concentration.

    PubMed

    Akasaka, Naoki; Astuti, Wiwik; Ishii, Yuri; Hidese, Ryota; Sakoda, Hisao; Fujiwara, Shinsuke

    2015-06-01

    Plasmids pGE1 (2.5 kb), pGE2 (7.2 kb), and pGE3 (5.5 kb) were isolated from Gluconacetobacter europaeus KGMA0119, and sequence analyses revealed they harbored 3, 8, and 4 genes, respectively. Plasmid copy numbers (PCNs) were determined by real-time quantitative PCR at different stages of bacterial growth. When KGMA0119 was cultured in medium containing 0.4% ethanol and 0.5% acetic acid, PCN of pGE1 increased from 7 copies/genome in the logarithmic phase to a maximum of 12 copies/genome at the beginning of the stationary phase, before decreasing to 4 copies/genome in the late stationary phase. PCNs for pGE2 and pGE3 were maintained at 1-3 copies/genome during all phases of growth. Under a higher concentration of ethanol (3.2%) the PCN for pGE1 was slightly lower in all the growth stages, and those of pGE2 and pGE3 were unchanged. In the presence of 1.0% acetic acid, PCNs were higher for pGE1 (10 copies/genome) and pGE3 (6 copies/genome) during the logarithmic phase. Numbers for pGE2 did not change, indicating that pGE1 and pGE3 increase their PCNs in response to acetic acid. Plasmids pBE2 and pBE3 were constructed by ligating linearized pGE2 and pGE3 into pBR322. Both plasmids were replicable in Escherichia coli, Acetobacter pasteurianus and G. europaeus, highlighting their suitability as vectors for acetic acid bacteria.

  16. Low plasma eicosapentaenoic acid concentration as a possible risk factor for intracerebral hemorrhage.

    PubMed

    Ikeya, Yoshimori; Fukuyama, Naoto; Mori, Hidezo

    2015-03-01

    N-3 fatty acids, including eicosapentaenoic acid (EPA), prevent ischemic stroke. The preventive effect has been attributed to an antithrombic effect induced by elevated EPA and reduced arachidonic acid (AA) levels. However, the relationship between intracranial hemorrhage and N-3 fatty acids has not yet been elucidated. In this cross-sectional study, we compared common clinical and lifestyle parameters between 70 patients with intracranial hemorrhages and 66 control subjects. The parameters included blood chemistry data, smoking, alcohol intake, fish consumption, and the incidences of underlying diseases. The comparisons were performed using the Mann-Whitney U test followed by multiple logistic regression analysis. Nonparametric tests revealed that the 70 patients with intracerebral hemorrhages exhibited significantly higher diastolic blood pressures and alcohol intakes and lower body mass indices, high-density lipoprotein (HDL) cholesterol levels, EPA concentrations, EPA/AA ratios, and vegetable consumption compared with the 66 control subjects. A multiple logistic regression analysis revealed that higher diastolic blood pressure and alcohol intake and lower body mass index, HDL cholesterol, EPA/AA ratio, and vegetable consumption were relative risk factors for intracerebral hemorrhage. High HDL cholesterol was a common risk factor in both of the sex-segregated subgroups and the <65-year-old subgroup. However, neither EPA nor the EPA/AA ratio was a risk factor in these subgroups. Eicosapentaenoic acid was relative risk factor only in the ≥65-year-old subgroup. Rather than higher EPA levels, lower EPA concentrations and EPA/AA ratios were found to be risk factors for intracerebral hemorrhage in addition to previously known risk factors such as blood pressure, alcohol consumption, and lifestyle.

  17. Beyond the FFA: The Role of the Ventral Anterior Temporal Lobes in Face Processing

    PubMed Central

    Collins, Jessica A.; Olson, Ingrid R.

    2014-01-01

    Extensive research has supported the existence of a specialized face-processing network that is distinct from the visual processing areas used for general object recognition. The majority of this work has been aimed at characterizing the response properties of the fusiform face area (FFA) and the occipital face area (OFA), which together are thought to constitute the core network of brain areas responsible for facial identification. Although accruing evidence has shown that face-selective patches in the ventral anterior temporal lobes (vATLs) are interconnected with the FFA and OFA, and that they play a role in facial identification, the relative contribution of these brain areas to the core face-processing network has remained unarticulated. Here we review recent research critically implicating the vATLs in face perception and memory. We propose that current models of face processing should be revised such that the ventral anterior temporal lobes serve a centralized role in the visual face-processing network. We speculate that a hierarchically organized system of face processing areas extends bilaterally from the inferior occipital gyri to the vATLs, with facial representations becoming increasingly complex and abstracted from low-level perceptual features as they move forward along this network. The anterior temporal face areas may serve as the apex of this hierarchy, instantiating the final stages of face recognition. We further argue that the anterior temporal face areas are ideally suited to serve as an interface between face perception and face memory, linking perceptual representations of individual identity with person-specific semantic knowledge. PMID:24937188

  18. Advances in Acid Concentration Membrane Technology for the Sulfur-Iodine Thermochemical Cycle

    SciTech Connect

    Frederick F. Stewart; Christopher J. Orme

    2006-11-01

    One of the most promising cycles for the thermochemical generation of hydrogen is the Sulfur-Iodine (S-I) process, where aqueous HI is thermochemically decomposed into H2 and I2 at approximately 350 degrees Celsius. Regeneration of HI is accomplished by the Bunsen reaction (reaction of SO2, water, and iodine to generate H2SO4 and HI). Furthermore, SO2 is regenerated from the decomposition of H2SO4 at 850 degrees Celsius yielding the SO2 as well as O2. Thus, the cycle actually consists of two concurrent oxidation-reduction loops. As HI is regenerated, co-produced H2SO4 must be separated so that each may be decomposed. Current flowsheets employ a large amount (~83 mol% of the entire mixture) of elemental I2 to cause the HI and the H2SO4 to separate into two phases. To aid in the isolation of HI, which is directly decomposed into hydrogen, water and iodine must be removed. Separation of iodine is facilitated by removal of water. Sulfuric acid concentration is also required to facilitate feed recycling to the sulfuric acid decomposer. Decomposition of the sulfuric acid is an equilibrium limited process that leaves a substantial portion of the acid requiring recycle. Distillation of water from sulfuric acid involves significant corrosion issues at the liquid-vapor interface. Thus, it is desirable to concentrate the acid without boiling. Recent efforts at the INL have concentrated on applying pervaporation through Nafion-117, Nafion-112, and sulfonated poly(etheretherketone) (S-PEEK) membranes for the removal of water from HI/water and HI/Iodine/water feedstreams. In pervaporation, a feed is circulated at low pressure across the upstream side of the membrane, while a vacuum is applied downstream. Selected permeants sorb into the membrane, transport through it, and are vaporized from the backside. Thus, a concentration gradient is established, which provides the driving force for transport. In this work, membrane separations have been performed at temperatures as high as

  19. Production and functional evaluation of a protein concentrate from giant squid (Dosidicus gigas) by acid dissolution and isoelectric precipitation.

    PubMed

    Cortés-Ruiz, Juan A; Pacheco-Aguilar, Ramón; Elena Lugo-Sánchez, M; Gisela Carvallo-Ruiz, M; García-Sánchez, Guillermina

    2008-09-15

    A protein concentrate from giant squid (Dosidicus gigas) was produced under acidic conditions and its functional-technological capability evaluated in terms of its gel-forming ability, water holding capacity and colour attributes. Technological functionality of the concentrate was compared with that of squid muscle and a neutral concentrate. Protein-protein aggregates insoluble at high ionic strength (I=0.5M), were detected in the acidic concentrate as result of processing with no preclusion of its gel-forming ability during the sol-to-gel thermal transition. Even though washing under acidic condition promoted autolysis of the myosin heavy chain, the acidic concentrate displayed an outstanding ability to gel giving samples with a gel strength of 455 and 1160gcm at 75% and 90% compression respectively, and an AA folding test grade indicative of high gel strength, elasticity, and cohesiveness. The process proved to be a good alternative for obtaining a functional protein concentrate from giant squid muscle.

  20. Modulating Membrane Composition Alters Free Fatty Acid Tolerance in Escherichia coli

    PubMed Central

    Lennen, Rebecca M.; Pfleger, Brian F.

    2013-01-01

    Microbial synthesis of free fatty acids (FFA) is a promising strategy for converting renewable sugars to advanced biofuels and oleochemicals. Unfortunately, FFA production negatively impacts membrane integrity and cell viability in Escherichia coli, the dominant host in which FFA production has been studied. These negative effects provide a selective pressure against FFA production that could lead to genetic instability at industrial scale. In prior work, an engineered E. coli strain harboring an expression plasmid for the Umbellularia californica acyl-acyl carrier protein (ACP) thioesterase was shown to have highly elevated levels of unsaturated fatty acids in the cell membrane. The change in membrane content was hypothesized to be one underlying cause of the negative physiological effects associated with FFA production. In this work, a connection between the regulator of unsaturated fatty acid biosynthesis in E. coli, FabR, thioesterase expression, and unsaturated membrane content was established. A strategy for restoring normal membrane saturation levels and increasing tolerance towards endogenous production of FFAs was implemented by modulating acyl-ACP pools with a second thioesterase (from Geobacillus sp. Y412MC10) that primarily targets medium chain length, unsaturated acyl-ACPs. The strategy succeeded in restoring membrane content and improving viability in FFA producing E. coli while maintaining FFA titers. However, the restored fitness did not increase FFA productivity, indicating the existence of additional metabolic or regulatory barriers. PMID:23349781

  1. Modulating membrane composition alters free fatty acid tolerance in Escherichia coli.

    PubMed

    Lennen, Rebecca M; Pfleger, Brian F

    2013-01-01

    Microbial synthesis of free fatty acids (FFA) is a promising strategy for converting renewable sugars to advanced biofuels and oleochemicals. Unfortunately, FFA production negatively impacts membrane integrity and cell viability in Escherichia coli, the dominant host in which FFA production has been studied. These negative effects provide a selective pressure against FFA production that could lead to genetic instability at industrial scale. In prior work, an engineered E. coli strain harboring an expression plasmid for the Umbellularia californica acyl-acyl carrier protein (ACP) thioesterase was shown to have highly elevated levels of unsaturated fatty acids in the cell membrane. The change in membrane content was hypothesized to be one underlying cause of the negative physiological effects associated with FFA production. In this work, a connection between the regulator of unsaturated fatty acid biosynthesis in E. coli, FabR, thioesterase expression, and unsaturated membrane content was established. A strategy for restoring normal membrane saturation levels and increasing tolerance towards endogenous production of FFAs was implemented by modulating acyl-ACP pools with a second thioesterase (from Geobacillus sp. Y412MC10) that primarily targets medium chain length, unsaturated acyl-ACPs. The strategy succeeded in restoring membrane content and improving viability in FFA producing E. coli while maintaining FFA titers. However, the restored fitness did not increase FFA productivity, indicating the existence of additional metabolic or regulatory barriers.

  2. Abscisic acid metabolizing rhizobacteria decrease ABA concentrations in planta and alter plant growth.

    PubMed

    Belimov, Andrey A; Dodd, Ian C; Safronova, Vera I; Dumova, Valentina A; Shaposhnikov, Alexander I; Ladatko, Alexander G; Davies, William J

    2014-01-01

    Although endogenous phytohormones such as abscisic acid (ABA) regulate root growth, and many rhizobacteria can modulate root phytohormone status, hitherto there have been no reports of rhizobacteria mediating root ABA concentrations and growth by metabolising ABA. Using a selective ABA-supplemented medium, two bacterial strains were isolated from the rhizosphere of rice (Oryza sativa) seedlings grown in sod-podzolic soil and assigned to Rhodococcus sp. P1Y and Novosphingobium sp. P6W using partial 16S rRNA gene sequencing and phenotypic patterns by the GEN III MicroPlate test. Although strain P6W had more rapid growth in ABA-supplemented media than strain P1Y, both could utilize ABA as a sole carbon source in batch culture. When rice seeds were germinated on filter paper in association with bacteria, root ABA concentration was not affected, but shoot ABA concentration of inoculated plants decreased by 14% (strain P6W) and 22% (strain P1Y). When tomato (Solanum lycopersicum) genotypes differing in ABA biosynthesis (ABA deficient mutants flacca - flc, and notabilis - not and the wild-type cv. Ailsa Craig, WT) were grown in gnotobiotic cultures on nutrient solution agar, rhizobacterial inoculation decreased root and/or leaf ABA concentrations, depending on plant and bacteria genotypes. Strain P6W inhibited primary root elongation of all genotypes, but increased leaf biomass of WT plants. In WT plants treated with silver ions that inhibit ethylene perception, both ABA-metabolising strains significantly decreased root ABA concentration, and strain P6W decreased leaf ABA concentration. Since these changes in ABA status also occurred in plants that were not treated with silver, it suggests that ethylene was probably not involved in regulating bacteria-mediated changes in ABA concentration. Correlations between plant growth and ABA concentrations in planta suggest that ABA-metabolising rhizobacteria may stimulate growth via an ABA-dependent mechanism.

  3. Lower Serum Bilirubin and Uric Acid Concentrations in Patients with Parkinson's Disease in China.

    PubMed

    Qin, Xiao-Ling; Zhang, Qing-Shan; Sun, Li; Hao, Meng-Wei; Hu, Zhao-Ting

    2015-05-01

    The objective of the study is to investigate the correlation between bilirubin and uric acid (UA) concentrations and symptoms of Parkinson's disease (PD) in Chinese population. A total of 425 PD patients and 460 controls were included in the current study. Patients were diagnosed by a neurologist and assessed using the Hoehn & Yahr (H&Y) scale. Venous blood samples were collected, and bilirubin and UA concentrations were analyzed. Compared to controls, indirect bilirubin (IBIL) and UA concentrations were lower in PD patients (P IBIL = 0.015, P UA = 0.000). Serum IBIL in different age subgroups and H&Y stage subgroups were also lower compared to the control group (P IBIL = 0.000, P UA = 0.000) but were not significantly different among these subgroups. Females in the control group had significantly lower serum IBIL and UA concentrations than males (P IBIL = 0.000, P UA = 0.000) and the PD group (P IBIL = 0.027, P UA = 0.000). In early PD (patients with <2-year medical history and no treatment), serum IBIL and UA concentrations were also lower than the controls (P IBIL = 0.013, P UA = 0.000). Although IBIL concentration was positively correlated with UA concentration in controls (R IBIL = 0.229, P IBIL = 0.004), this positive association was not observed in the PD group (R IBIL = -0.032, P IBIL = 0.724). Decreased levels of serum IBIL and UA were observed in PD patients. It is possible that individuals with decreased serum bilirubin and UA concentrations lack the endogenous defense system to prevent peroxynitrite and other free radicals from damaging and destroying dopaminergic cells in the substantia nigra. Our results provide a basis for further investigation into the role of bilirubin in PD.

  4. Water Deficit-Induced Changes in Concentrations in Proline and Some Other Amino Acids in the Phloem Sap of Alfalfa.

    PubMed

    Girousse, C.; Bournoville, R.; Bonnemain, J. L.

    1996-05-01

    Changes in amino acid composition of alfalfa (Medicago sativa L.) phloem sap were studies in response to a water deficit. Sap was collected by stylectomy. As the leaf water potential ([psi]) decreased from -0.4 to -2.0 MPa, there was significant increase of the total amino acid concentration, due to that of some amino acids: proline, valine, isoleucine, leucine, glutamic acid, aspartic acid, and threonine. Asparagine concentration, which is the main amino acid assayed in the phloem sap of alfalfa (it accounts for 70% of the total content), did not vary with the plant water status. The other amino acid concentrations remained stable as [psi] varied; in particular, [gamma]-amino butyric acid concentration remained unchanged, whereas it varied in response to wounding. The more striking change in the sieve tubes was the accumulation of proline, which was observed below a [psi] threshold value of about -0.9 MPa (concentration x60 for a decrease of [psi] from -0.9 to -2.0 MPa). The role of such changes in phloem sap amino acid concentration in osmotic adjustment of growing tissues is discussed.

  5. Regulation of dipeptide transport in Saccharomyces cerevisiae by micromolar amino acid concentrations

    SciTech Connect

    Island, M.D.; Naider, F.; Becker, J.M.

    1987-05-01

    Prototrophic Saccharomyces cerevisiae X2180, when grown on unsupplemented minimal medium, displayed little sensitivity to ethionine- and m-fluorophenylalanine-containing toxic dipeptides. The authors examined the influence of the 20 naturally occurring amino acids on sensitivity to toxic dipeptides. A number of these amino acids, at concentrations as low as 1 ..mu..M (leucine and tryptophan), produced large increases in sensitivity to leucyl-ethionine, alanyl-ethionine, and leucyl-m-fluorophenylalanine. Sensitivity to ethionine and m-fluorophenylalanine remained high under either set of conditions. The addition of 0.15 mM tryptophan to a growing culture resulted in the induction of dipeptide transport, as indicated by a 25-fold increase in the initial rate of L-leucyl-L(/sup 3/H)leucine accumulation. This increase, which was prevented by the addition of cycloheximide, began within 30 min and peaked approximately 240 min after a shift to medium containing tryptophan. Comparable increases in peptidase activity were not apparent in crude cell extracts form tryptophan-induced cultures. The authors concluded that S. cerevisiae possesses a specific mechanism for the induction of dipeptidetransport that can respond to very low concentrations of amino acids.

  6. Effects of different silanes and acid concentrations on bond strength of brackets to porcelain surfaces.

    PubMed

    Trakyali, Göksu; Malkondu, Ozlem; Kazazoğlu, Ender; Arun, Tülin

    2009-08-01

    The aim of this study was to determine the optimum silane-coupling agent and the optimum concentration of acid agent when bonding to porcelain surfaces. Eighty deglazed feldspathic porcelain discs with a diameter of 10 mm and a thickness of 2 mm mounted in acrylic resin blocks were randomly divided into four groups. In groups 1 and 2, the porcelain surfaces were etched with 9.6 per cent hydrofluoric (HF) acid and in groups 3 and 4 with 5 per cent HF acid. In groups 1 and 3, the Dynalock maxillary central incisor brackets were bonded with Pulpdent silane and Unite bonding adhesive and in groups 2 and 4 with Reliance silane and Unite. Shear forces were applied to the samples using an Instron universal test machine. The non-parametric Kruskal-Wallis test was used to determine significant differences in bond strengths between the four groups and Dunn's multiple comparison test to compare subgroups. The mean bond strengths and standard deviations of groups 1 to 4 were 5.51 +/- 1.19, 6.54 +/- 0.002, 4.55 +/- 1.93, and 6.39 +/- 0.45 MPa, respectively. Specimens bonded with Reliance showed a statistically significantly higher in vitro bond strength than those bonded with Pulpdent. The concentration of etching gels did not result in any statistically significant difference on the in vitro bond strength when evaluated separately.

  7. Effect of acid concentration and pulp properties on hydrolysis reactions of mercerized sisal.

    PubMed

    Lacerda, Talita M; Zambon, Márcia D; Frollini, Elisabete

    2013-03-01

    The influence of sulfuric acid concentration (H2SO4 5-25%, 100°C), crystallinity and fibers size on the hydrolysis reaction of sisal pulps were investigated, with the goal of evaluating both the liquor composition, as an important step in the production of bioethanol, and the residual non-hydrolyzed pulp, to determine its potential application as materials. Aliquots were withdrawn from the reaction media, and the liquor composition was analyzed by HPLC. The residual non-hydrolyzed pulps were characterized by SEM, their average molar mass and crystallinity index, and their size distribution was determined using a fiber analyzer. Sulfuric acid 25% led to the highest glucose content (approximately 10gL(-1)), and this acid concentration was chosen to evaluate the influence of both the fiber size and crystallinity of the starting pulp on hydrolysis. The results showed that fibers with higher length and lower crystallinity favored glucose production in approximately 12%, with respect to the highly crystalline shorter fibers.

  8. An Examination of Middle School Enrollment in Agricultural Education and Membership in the National FFA Organization in the United States. Summary of Research 73.

    ERIC Educational Resources Information Center

    Rossetti, Rosemarie; And Others

    The status of middle and junior high school agricultural education and Future Farmers of America (FFA) programs in the United States was the focus of a study. Data were collected through a census of the FFA executive secretaries and a survey of a purposive sample of 27 successful middle or junior high school agricultural education programs in 9…

  9. Hexavalent uranium diffusion into soils from concentrated acidic and alkaline solutions

    SciTech Connect

    Tokunaga, Tetsu K.; Wan, Jiamin; Pena, Jasquelin; Sutton, Stephen R.; Newville, Matthew

    2004-03-29

    Uranium contamination of soils and sediments often originates from acidic or alkaline waste sources, with diffusion being a major transport mechanism. Measurements of U(VI) diffusion from initially pH 2 and pH 11 solutions into a slightly alkaline Altamont soil and a neutral Oak Ridge soil were obtained through monitoring uptake from boundary reservoirs and from U concentration profiles within soil columns. The soils provided pH buffering, resulting in diffusion at nearly constant pH. Micro x-ray absorption near edge structure spectra confirmed that U remained in U(VI) forms in all soils. Time trends of U(VI) depletion from reservoirs, and U(VI) concentration profiles within soil columns yielded K{sub d} values consistent with those determined in batch tests at similar concentrations ({approx} 1 mM), and much lower than values for sorption at much lower concentrations (nM to {mu}M). These results show that U(VI) transport at high concentrations can be relatively fast at non-neutral pH, with negligible surface diffusion, because of weak sorption.

  10. Rare earth element concentrations in dissolved and acid available particulate forms for eastern UK rivers

    NASA Astrophysics Data System (ADS)

    Neal, C.

    2007-01-01

    Variations in concentration of yttrium (Y), lanthanum (La), cerium (Ce), neodymium (Nd), samarium (Sm) and gadolinium (Gd) among rivers of eastern England and the border with Scotland are described in relation to the dissolved (<0.45 µM) fraction and acid-available particulate (AAP) fractions. The rivers cover a range of rural, agricultural and urban/industrial environments. Yttrium and the lanthanides show significant levels of both dissolved and acid-available particulate forms (typically about 40% in the dissolved form). For the dissolved phase, Y and the lanthanides are linearly correlated with each other and with iron: most of this dissolved component may be in a micro-particulate/colloidal form. The Y and lanthanide relationships show marked scatter and there are anomalously high La concentrations at times for the rivers Great Ouse, Thames and Wear that are probably linked to pollutant sources. For the Ouse, and especially for one of its tributaries, the Swale, relatively high Sm concentrations are probably associated with mineralisation within the catchment and contamination of the associated flood plain. For the AAP components, there are strong linear relationships with Y and the lanthanides across all the rivers. There is also a strong link between these AAP associated REE and AAP iron, although the scatter is greater and the industrial rivers have a lower lanthanide to iron ratio, probably due to iron-rich contaminants.

  11. Effect of polymer species and concentration on the production of mefenamic acid nanoparticles by media milling.

    PubMed

    Ito, Atsutoshi; Konnerth, Christoph; Schmidt, Jochen; Peukert, Wolfgang

    2016-01-01

    The effect of four structurally different polymer species (hydroxypropylcellulose, polyvinylpyrrolidone, vinylpyrrolidone-vinyl acetate copolymer and polyvinyl alcohol) on the production of mefenamic acid nanoparticles during media milling has been studied. It was found that product particle sizes are strongly determined by the type of polymeric stabiliser as well as by its concentration at constant process conditions. With respect to small product particle sizes an optimum excipient concentration was identified and adjusted for colloidal stability of the drug nanosuspensions. Furthermore, it was found that overdosing of excipients must be omitted to suppress ripening due to enhanced solubilisation phenomena. Hence, the smallest product particle sizes were obtained using a polymeric stabiliser which exhibits a high affinity to the model drug compound and a low solubilisation capacity. Affinities of each polymer species to mefenamic acid and corresponding surface concentrations were determined using straightforward and simple viscosity measurements of the supernatant. A relationship between polymer affinity, solubilisation capacity and limiting product particle size has been observed, which supports the hypothesis that final product particle sizes are rather determined by the solid-liquid equilibrium than by pure mechanical fracture.

  12. Physiological and transcriptional responses to high concentrations of lactic acid in anaerobic chemostat cultures of Saccharomyces cerevisiae.

    PubMed

    Abbott, Derek A; Suir, Erwin; van Maris, Antonius J A; Pronk, Jack T

    2008-09-01

    Based on the high acid tolerance and the simple nutritional requirements of Saccharomyces cerevisiae, engineered strains of this yeast are considered biocatalysts for industrial production of high-purity undissociated lactic acid. However, high concentrations of lactic acid are toxic to S. cerevisiae, thus limiting its growth and product formation. Physiological and transcriptional responses to high concentrations of lactic acid were studied in anaerobic, glucose-limited chemostat cultures grown at different pH values and lactic acid concentrations, resulting in a 50% decrease in the biomass yield. At pH 5, the yield decrease was caused mostly by osmotically induced glycerol production and not by the classic weak-acid action, as was observed at pH 3. Cultures grown at pH 5 with 900 mM lactic acid revealed an upregulation of many genes involved in iron homeostasis, indicating that iron chelation occurred at high concentrations of dissociated lactic acid. Chemostat cultivation at pH 3 with 500 mM lactate, resulting in lower anion concentrations, showed an alleviation of this iron homeostasis response. Six of the 10 known targets of the transcriptional regulator Haa1p were strongly upregulated in lactate-challenged cultures at pH 3 but showed only moderate induction by high lactate concentrations at pH 5. Moreover, the haa1Delta mutant exhibited a growth defect at high lactic acid concentrations at pH 3. These results indicate that iron homeostasis plays a major role in the response of S. cerevisiae to high lactate concentrations, whereas the Haa1p regulon is involved primarily in the response to high concentrations of undissociated lactic acid.

  13. Factors Related to the Success of New Mexico Vocational Agriculture Teachers as FFA Advisors. Summary of Research.

    ERIC Educational Resources Information Center

    Vaughan, Paul R.; Bender, Ralph E.

    This study was designed to (1) identify competencies in which a New Mexico vocational agriculture teacher's perceived level of proficiency was related to the degree of success of his Future Farmers of America (FFA) chapter, (2) identify characteristics possessed by New Mexico vocational agriculture teachers which showed a significant relationship…

  14. Influence of acid volatile sulfides and metal concentrations on metal partitioning in contaminated sediments

    USGS Publications Warehouse

    Lee, J.-S.; Lee, B.-G.; Luoma, S.N.; Choi, H.J.; Koh, C.-H.; Brown, C.L.

    2000-01-01

    The influence of acid volatile sulfide (AVS) on the partitioning of Cd, Ni, and Zn in porewater (PW) and sediment as reactive metals (SEM, simultaneously extracted metals) was investigated in laboratory microcosms. Two spiking procedures were compared, and the effects of vertical geochemical gradients and infaunal activity were evaluated. Sediments were spiked with a Cd-Ni-Zn mixture (0.06, 3, 7.5 ??mol/g, respectively) containing four levels of AVS (0.5, 7.5, 15, 35 ??mol/g). The results were compared to sediments spiked with four levels of Cd-Ni-Zn mixtures at one AVS concentration (7.5 ??mol/g). A vertical redox gradient was generated in each treatment by an 18-d incubation with an oxidized water column. [AVS] in the surface sediments decreased by 65-95% due to oxidation during incubation; initial [AVS] was maintained at 0.5-7.5 cm depth. PW metal concentrations were correlated with [SEM - AVS] among all data. But PW metal concentrations were variable, causing the distribution coefficient, Kd(pw) (the ratio of [SEM] to PW metal concentrations) to vary by 2-3 orders of magnitude at a given [SEM - AVS]. One reason for the variability was that vertical profiles in PW metal concentrations appeared to be influenced by diffusion as well as [SEM - AVS]. The presence of animals appeared to enhance the diffusion of at least Zn. The generalization that PW metal concentrations are controlled by [SEM - AVS] is subject to some important qualifications if vertical gradients are complicated, metal concentrations vary, or equilibration times differ.The influence of acid volatile sulfide (AVS) on the partitioning of Cd, Ni, and Zn in porewater (PW) and sediment as reactive metals (SEM, simultaneously extracted metals) was investigated in laboratory microcosms. Two spiking procedures were compared, and the effects of vertical geochemical gradients and infaunal activity were evaluated. Sediments were spiked with a Cd-Ni-Zn mixture (0.06, 3, 7.5 ??mol/g, respectively) containing

  15. Relationship between body fat mass and free fatty acid kinetics in men and women.

    PubMed

    Mittendorfer, Bettina; Magkos, Faidon; Fabbrini, Elisa; Mohammed, B Selma; Klein, Samuel

    2009-10-01

    An increased release of free fatty acids (FFAs) into plasma likely contributes to the metabolic complications associated with obesity. However, the relationship between body fat and FFA metabolism is unclear because of conflicting results from different studies. The goal of our study was to determine the inter-relationships between body fat, sex, and plasma FFA kinetics. We determined FFA rate of appearance (Ra) in plasma, by using stable isotopically labeled tracer techniques, during basal conditions in 106 lean, overweight, and obese, nondiabetic subjects (43 men and 63 women who had 7.0-56.0% body fat). Correlation analyses demonstrated: (i) no differences between men and women in the relationship between fat mass (FM) and total FFA Ra (micromol/min); (ii) total FFA Ra increased linearly with increasing FM (r=0.652, P<0.001); (iii) FFA Ra per kg FM decreased in a curvilinear fashion with increasing FM (r=-0.806; P<0.001); (iv) FFA Ra in relationship to fat-free mass (FFM) was greater in obese than lean subjects and greater in women than in men; and (v) abdominal fat itself was not an important determinant of total FFA Ra. We conclude that total body fat, not regional fat distribution or sex, is an important modulator of the rate of FFA release into plasma. Although increased adiposity is associated with a decrease in fatty acid release in relationship to FM, this downregulation is unable to completely compensate for the increase in FM, so total FFA Ra and FFA Ra with respect to FFM are greater in women than in men and in obese than in lean subjects.

  16. New method for the direct determination of dissolved Fe(III) concentration in acid mine waters

    USGS Publications Warehouse

    To, T.B.; Nordstrom, D.K.; Cunningham, K.M.; Ball, J.W.; McCleskey, R.B.

    1999-01-01

    A new method for direct determination of dissolved Fe(III) in acid mine water has been developed. In most present methods, Fe(III) is determined by computing the difference between total dissolved Fe and dissolved Fe(II). For acid mine waters, frequently Fe(II) >> Fe(III); thus, accuracy and precision are considerably improved by determining Fe(III) concentration directly. The new method utilizes two selective ligands to stabilize Fe(III) and Fe(II), thereby preventing changes in Fe reduction-oxidation distribution. Complexed Fe(II) is cleanly removed using a silica-based, reversed-phase adsorbent, yielding excellent isolation of the Fe(III) complex. Iron(III) concentration is measured colorimetrically or by graphite furnace atomic absorption spectrometry (GFAAS). The method requires inexpensive commercial reagents and simple procedures that can be used in the field. Calcium(II), Ni(II), Pb(II), AI(III), Zn(II), and Cd(II) cause insignificant colorimetric interferences for most acid mine waters. Waters containing >20 mg of Cu/L could cause a colorimetric interference and should be measured by GFAAS. Cobalt(II) and Cr(III) interfere if their molar ratios to Fe(III) exceed 24 and 5, respectively. Iron(II) interferes when its concentration exceeds the capacity of the complexing ligand (14 mg/L). Because of the GFAAS elemental specificity, only Fe(II) is a potential interferent in the GFAAS technique. The method detection limit is 2 ??g/L (40 nM) using GFAAS and 20 ??g/L (0.4 ??M) by colorimetry.A new method for direct determination of dissolved Fe(III) in acid mine water has been developed. In most present methods, Fe(III) is determined by computing the difference between total dissolved Fe and dissolved Fe(II). For acid mine waters, frequently Fe(II)???Fe(III); thus, accuracy and precision are considerably improved by determining Fe(III) concentration directly. The new method utilizes two selective ligands to stabilize Fe(III) and Fe(II), thereby preventing changes

  17. Treatment with clozapine and its effect on plasma homovanillic acid and norepinephrine concentrations in schizophrenia.

    PubMed

    Davidson, M; Kahn, R S; Stern, R G; Hirschowitz, J; Apter, S; Knott, P; Davis, K L

    1993-02-01

    Measurement of plasma concentrations of the dopamine metabolite, homovanillic acid (pHVA), is an indirect tool to assess changes in dopamine turnover. Levels of pHVA have been reported to decrease during treatment with conventional antidopaminergic, neuroleptics, with the decrement correlating with symptomatic improvement in schizophrenic symptoms. Clozapine, an atypical neuroleptic, is the only drug proved to be effective in treatment-refractory patients. However, the mechanism mediating this unique efficacy has not been fully elucidated. This study examined the effect of clozapine on pHVA concentrations in schizophrenic patients. Since clozapine potently binds to alpha 2-adrenergic receptors, plasma norepinephrine (pNE) concentrations were also measured. Twenty-eight treatment-refractory schizophrenic patients (24 men, 4 women) were treated with clozapine (up to 600 mg/day) for 5 weeks, after a minimum 1-week drug-free period. Symptomatology and pHVA and pNE concentrations were measured at the last drug-free day and weekly for 5 weeks. Fourteen patients responded to clozapine treatment, while an equal number did not. Mean pHVA concentrations did not significantly change during treatment with clozapine. Although clozapine tended to lower pHVA concentrations in treatment responders, the effect was small and not significant. Clozapine treatment significantly raised pNE concentrations, but this did not differentiate responders from nonresponders to clozapine. These findings suggest that clozapine's effect on DA turnover is small and that clozapine may be effective in treatment-refractory schizophrenia by mechanisms other than, or in addition to, dopamine receptor blockade. However, since about one-third of NE is metabolized into HVA, the clozapine-induced increase in pNE may have overshadowed a possible lowering effect of clozapine on pHVA.

  18. Relevance of carnosic acid, carnosol, and rosmarinic acid concentrations in the in vitro antioxidant and antimicrobial activities of Rosmarinus officinalis (L.) methanolic extracts.

    PubMed

    Jordán, Maria J; Lax, Vanesa; Rota, Maria C; Lorán, Susana; Sotomayor, José A

    2012-09-26

    The importance of the diterpenic and rosmarinic acid content in the biological activities of rosemary extracts has been studied previously, but how the relationship between the concentration of these components affects their antioxidant and antibacterial activities has received little attention. Accordingly, from a total of 150 plants, 27 methanolic extracts were selected, for their similar diterpene contents but different ratios between carnosic acid and carnosol concentrations. In extracts with similar rosmarinic acid contents but differing proportions between carnosic acid and carnosol, the two diterpenes were seen to equally affect the in vitro antioxidant activity; however, and related with the antibacterial efficiency, this biological activity improved when carnosol was the major diterpene component.

  19. Hardening with salicylic acid induces concentration-dependent changes in abscisic acid biosynthesis of tomato under salt stress.

    PubMed

    Horváth, Edit; Csiszár, Jolán; Gallé, Ágnes; Poór, Péter; Szepesi, Ágnes; Tari, Irma

    2015-07-01

    The role of salicylic acid (SA) in the control of abscisic acid (ABA) biosynthesis is controversial although both plant growth regulators may accumulate in tissues under abiotic and biotic stress conditions. Hardening of tomato plants to salinity stress with 10(-4)M SA ("high SA") resulted in an up-regulation of ABA biosynthesis genes, zeaxanthin epoxidase (SlZEP1), 9-cis-epoxycarotenoid dioxygenase (SlNCED1) and aldehyde oxidases (SlAO1 and SlAO2) in the roots and led to ABA accumulation both in root and leaf tissues. In plants pre-treated with lower concentration of SA (10(-7)M, "low SA"), the up-regulation of SlNCED1 in the roots promoted ABA accumulation in the root tissues but the hormone concentration remained at control level in the leaves. Salt stress induced by 100mM NaCl reduced the transcript abundance of ABA biosynthetic genes and inhibited SlAO activity in plants hardened with "high SA", but the tissues maintained root ABA level over the untreated control. The combined effect of "high SA" and ABA under salt stress led to partially recovered photosynthetic activity, reduced ethylene production in root apices, and restored root growth, which is one of the main features of salt tolerance. Unlike "high SA", hardening with "low SA" had no influence on ethylene production, and led to reduced elongation of roots in plants exposed to 100mM NaCl. The up-regulation of carotenoid cleavage dioxygenases SlCCD1A and SlCCD1B by SA, which produce apocarotenoids, may open new pathways in SA sensing and signalling processes.

  20. High concentrations of stavudine impair fatty acid oxidation without depleting mitochondrial DNA in cultured rat hepatocytes.

    PubMed

    Igoudjil, Anissa; Massart, Julie; Begriche, Karima; Descatoire, Véronique; Robin, Marie-Anne; Fromenty, Bernard

    2008-06-01

    The antiretroviral nucleoside reverse-transcriptase inhibitor (NRTI) stavudine (d4T) can induce mild to severe liver injuries such as steatosis (i.e. triglyceride accumulation), steatohepatitis and liver failure. NRTI-induced toxicity has been ascribed to the inhibition of mitochondrial DNA (mtDNA) replication causing mtDNA depletion and respiratory chain dysfunction. This can secondarily impair the tricarboxylic acid cycle and fatty acid oxidation (FAO), thus leading to lactic acidosis and hepatic steatosis. However, NRTIs could also impair mitochondrial function and induce hepatic steatosis through other mechanisms. In this study, we sought to determine whether d4T could inhibit mitochondrial FAO and induce triglyceride accumulation through a mtDNA-independent mechanism. Since human tumoral and non-tumoral hepatic cell lines were unable to efficiently oxidize palmitic acid, the effects of d4T on mitochondrial FAO were assessed on cultured rat hepatocytes. Our results showed that 750 microM of d4T significantly inhibited palmitic acid oxidation after 48 or 72 h of culture, without inducing cell death. Importantly, high concentrations of zidovudine and zalcitabine (two other NRTIs that can induce hepatic steatosis), or beta-aminoisobutyric acid (a d4T metabolite), did not impair FAO in rat hepatocytes. D4T-induced FAO inhibition was observed without mtDNA depletion and lactate production, and was fully prevented with l-carnitine or clofibrate coincubation. l-carnitine also prevented the accretion of neutral lipids within rat hepatocytes. High concentrations of d4T were unable to inhibit FAO on freshly isolated liver mitochondria. Moreover, a microarray analysis was performed to clarify the mechanism whereby d4T can inhibit mitochondrial FAO and induce triglyceride accumulation in rat hepatocytes. The microarray data, confirmed by quantitative real-time PCR analysis, showed that d4T increased the expression of sterol regulatory element-binding protein-1c (SREBP1c

  1. Acyl Ghrelin Induces Insulin Resistance Independently of GH, Cortisol, and Free Fatty Acids

    PubMed Central

    Vestergaard, Esben T.; Jessen, Niels; Møller, Niels; Jørgensen, Jens Otto Lunde

    2017-01-01

    Ghrelin produced in the gut stimulates GH and ACTH secretion from the pituitary and also stimulates appetite and gastric emptying. We have shown that ghrelin also induces insulin resistance via GH-independent mechanisms, but it is unknown if this effect depends on ambient fatty acid (FFA) levels. We investigated the impact of ghrelin and pharmacological antilipolysis (acipimox) on insulin sensitivity and substrate metabolism in 8 adult hypopituitary patients on stable replacement with GH and hydrocortisone using a 2 × 2 factorial design: Ghrelin infusion, saline infusion, ghrelin plus short-term acipimox, and acipimox alone. Peripheral and hepatic insulin sensitivity was determined with a hyperinsulinemic euglycemic clamp in combination with a glucose tracer infusion. Insulin signaling was assayed in muscle biopsies. Peripheral insulin sensitivity was reduced by ghrelin independently of ambient FFA concentrations and was increased by acipimox independently of ghrelin. Hepatic insulin sensitivity was increased by acipimox. Insulin signaling pathways in skeletal muscle were not consistently regulated by ghrelin. Our data demonstrate that ghrelin induces peripheral insulin resistance independently of GH, cortisol, and FFA. The molecular mechanisms remain elusive, but we speculate that ghrelin is a hitherto unrecognized direct regulator of substrate metabolism. We also suggest that acipimox per se improves hepatic insulin sensitivity. PMID:28198428

  2. GPR40/FFA1 and Neutral Sphingomyelinase Are Involved in Palmitate-Boosted Inflammatory Response of Microvascular Endothelial Cells to LPS

    PubMed Central

    Lu, Zhongyang; Li, Yanchun; Jin, Junfei; Zhang, Xiaoming; Hannun, Yusuf A.; Huang, Yan

    2015-01-01

    Objectives Increased levels of both saturated fatty acids (SFAs) and lipopolysaccharide (LPS) are associated with type 2 diabetes. However, it remains largely unknown how SFAs interact with LPS to regulate inflammatory responses in microvascular endothelial cells (MIC ECs) that are critically involved in atherosclerosis as a diabetic complication. In this study, we compared the effects of LPS, palmitic acid (PA), the most abundant saturated fatty acid, or the combination of LPS and PA on interleukin (IL)-6 expression by MIC ECs and explored the underlying mechanisms. Methods Human cardiac MIC ECs were treated with LPS, PA and LPS plus PA and the regulatory pathways including receptors, signal transduction, transcription and post-transcription, and sphingolipid metabolism for IL-6 expression were investigated. Results G protein-coupled receptor (GPR)40 or free fatty acid receptor 1 (FFA1), but not toll-like receptor 4, was involved in PA-stimulated IL-6 expression. PA not only stimulated IL-6 expression by itself, but also remarkably enhanced LPS-stimulated IL-6 expression via a cooperative stimulation on mitogen-activated protein kinase and nuclear factor kappa B signaling pathways, and both transcriptional and post-transcriptional activation. Furthermore, PA induced a robust neutral sphingomyelinase (nSMase)-mediated sphingomyelin hydrolysis that was involved in PA-augmented IL-6 upregulation. Conclusion PA boosted inflammatory response of microvascular endothelial cells to LPS via GPR40 and nSMase. PMID:25795558

  3. Concentration Dependent Influence of Lipopolysaccharides on Separation of Hoof Explants and Supernatant Lactic Acid Concentration in an Ex Vivo/In Vitro Laminitis Model.

    PubMed

    Reisinger, Nicole; Schaumberger, Simone; Nagl, Veronika; Hessenberger, Sabine; Schatzmayr, Gerd

    2015-01-01

    Laminitis is one of the most common diseases in horses. It is not only painful for the animal, but also has a significant financial impact on the equine industry. This multifactorial disease affects the connective tissue of the hoof. However, the pathogenesis of laminitis is still not fully understood. Endotoxins, also known as lipopolysaccharides (LPS), and bacterial exotoxins seem to play an important role during the development of laminitis. The aim of our study was to investigate the effect of increasing LPS concentrations (0, 2.5, 5, 10, and 100 μg/mL) on cell viability of isolated epidermal and dermal hoof cells as well as on the tissue integrity of hoof explants. Furthermore, glucose, acetic acid, lactic acid, and propionic acid concentrations in explant supernatants were measured to evaluate the energy metabolism in the hoof tissue. LPS did not exhibit cytotoxic effects on epidermal or dermal cells. Force required to separate LPS treated hoof explants decreased in a concentration dependent manner. Specifically, explants incubated with 10 and 100 μg/mL needed significantly less force to separate compared to control explants. Lactic acid concentrations were significantly decreased in explants incubated with 5, 10, or 100 μg/mL LPS, while glucose, acetic acid and propionic acid concentrations were unaffected by LPS treatment. Our study indicates that LPS has no cytotoxic effect on epidermal and dermal cells isolated from hoof tissue, but impairs integrity of hoof explants. In addition, LPS led to an alteration of the lactic acid production in the lamellar tissue. Since our data highlight that LPS can affect the integrity of the equine hoof tissue in vitro, endotoxins should be further explored for their contribution to facilitate the development of laminitis.

  4. Concentration Dependent Influence of Lipopolysaccharides on Separation of Hoof Explants and Supernatant Lactic Acid Concentration in an Ex Vivo/In Vitro Laminitis Model

    PubMed Central

    Reisinger, Nicole; Schaumberger, Simone; Nagl, Veronika; Hessenberger, Sabine; Schatzmayr, Gerd

    2015-01-01

    Laminitis is one of the most common diseases in horses. It is not only painful for the animal, but also has a significant financial impact on the equine industry. This multifactorial disease affects the connective tissue of the hoof. However, the pathogenesis of laminitis is still not fully understood. Endotoxins, also known as lipopolysaccharides (LPS), and bacterial exotoxins seem to play an important role during the development of laminitis. The aim of our study was to investigate the effect of increasing LPS concentrations (0, 2.5, 5, 10, and 100 μg/mL) on cell viability of isolated epidermal and dermal hoof cells as well as on the tissue integrity of hoof explants. Furthermore, glucose, acetic acid, lactic acid, and propionic acid concentrations in explant supernatants were measured to evaluate the energy metabolism in the hoof tissue. LPS did not exhibit cytotoxic effects on epidermal or dermal cells. Force required to separate LPS treated hoof explants decreased in a concentration dependent manner. Specifically, explants incubated with 10 and 100 μg/mL needed significantly less force to separate compared to control explants. Lactic acid concentrations were significantly decreased in explants incubated with 5, 10, or 100 μg/mL LPS, while glucose, acetic acid and propionic acid concentrations were unaffected by LPS treatment. Our study indicates that LPS has no cytotoxic effect on epidermal and dermal cells isolated from hoof tissue, but impairs integrity of hoof explants. In addition, LPS led to an alteration of the lactic acid production in the lamellar tissue. Since our data highlight that LPS can affect the integrity of the equine hoof tissue in vitro, endotoxins should be further explored for their contribution to facilitate the development of laminitis. PMID:26599864

  5. Computational Study of the Malonic Acid Tautomerization Products in Highly Concentrated Particles

    DOE PAGES

    Dick-Pérez, Marilú; Windus, Theresa L.

    2017-03-09

    Knowing the tautomeric form of malonic acid (MA) in concentrated particles is critical to understanding its effect on the atmosphere. Energies and vibrational modes of hydrated MA particles were calculated using density functional theory (DFT) at the B3LYP/6-31G(d,p) level and the effective fragment potential (EFP) method. Visualization of the keto and enol isomer vibrational modes enabled the assignment of keto isomer peaks in the 1710–1750 cm–1 range, and previously unidentified experimental IR peaks in the 1690–1710 cm–1 can now be attributed to the enol isomer. Furthermore, a comparison of calculated spectra of pure hydrated enol or keto isomers confirm recentmore » experimental evidence, of a shift in the keto–enol tautomer equilibrium when MA exists as concentrated particles.« less

  6. Computational Study of the Malonic Acid Tautomerization Products in Highly Concentrated Particles.

    PubMed

    Dick-Pérez, Marilú; Windus, Theresa L

    2017-03-23

    Knowing the tautomeric form of malonic acid (MA) in concentrated particles is critical to understanding its effect on the atmosphere. Energies and vibrational modes of hydrated MA particles were calculated using density functional theory (DFT) at the B3LYP/6-31G(d,p) level and the effective fragment potential (EFP) method. Visualization of the keto and enol isomer vibrational modes enabled the assignment of keto isomer peaks in the 1710-1750 cm(-1) range, and previously unidentified experimental IR peaks in the 1690-1710 cm(-1) can now be attributed to the enol isomer. Comparison of calculated spectra of pure hydrated enol or keto isomers confirm recent experimental evidence, presented by Ghorai et al. ( J. Phys. Chem. A 2011 , 115 , 4373 - 4380 ) of a shift in the keto-enol tautomer equilibrium when MA exists as concentrated particles.

  7. Humic acid transport in saturated porous media: influence of flow velocity and influent concentration.

    PubMed

    Wei, Xiaorong; Shao, Mingan; Du, Lina; Horton, Robert

    2014-12-01

    Understanding the transport of humic acids (HAs) in porous media can provide important and practical evidence needed for accurate prediction of organic/inorganic contaminant transport in different environmental media and interfaces. A series of column transport experiments was conducted to evaluate the transport of HA in different porous media at different flow velocities and influent HA concentrations. Low flow velocity and influent concentration were found to favor the adsorption and deposition of HA onto sand grains packed into columns and to give higher equilibrium distribution coefficients and deposition rate coefficients, which resulted in an increased fraction of HA being retained in columns. Consequently, retardation factors were increased and the transport of HA through the columns was delayed. These results suggest that the transport of HA in porous media is primarily controlled by the attachment of HA to the solid matrix. Accordingly, this attachment should be considered in studies of HA behavior in porous media.

  8. Faecal pH, bile acid and sterol concentrations in premenopausal Indian and white vegetarians compared with white omnivores.

    PubMed

    Reddy, S; Sanders, T A; Owen, R W; Thompson, M H

    1998-06-01

    Faecal bulk, pH, water content, the concentrations of neutral sterols and bile acids and dietary intakes were measured in twenty-two Indian vegetarian, twenty-two white omnivorous and eighteen white vegetarian premenopausal women. Faecal bulk and water content were greater and pH lower in the Indian vegetarians. Total faecal animal sterol and coprostanol concentrations expressed on a dry-weight basis were lower in the vegetarians compared with the omnivores. The faecal sterol concentrations were correlated with dietary cholesterol intake. Primary bile acids were detected in six Indian vegetarians, two white vegetarians and two white omnivores; secondary bile acids were detected in all the white omnivores and vegetarian subjects but not in two of the Indian vegetarians. Total faecal free bile acid and conjugated bile acid concentrations were lower in the white vegetarians compared with the omnivores. Faecal lithocholic acid concentrations were lower in both Indian and white vegetarians. The lithocholic: deoxycholic acid ratio and coprostanol: total animal sterols ratio were significantly lower in the Indian vegetarians compared with the omnivores. Both ratios were positively correlated with faecal pH. Stepwise multiple regression analyses were undertaken in order to identify which nutrients influenced faecal pH, lithocholic and deoxycholic acid concentrations. The intakes of starch and dietary fibre were negatively associated with faecal concentrations of lithocholic and deoxycholic acid. Starch intake alone was negatively associated with faecal pH. The results of this study confirm that diets high in dietary fibre decrease faecal bile acid concentrations and suggest that the complex carbohydrates present in Indian vegetarian diets influence faecal pH and inhibit the degradation of faecal steroids.

  9. Associations between concentrations of uric acid with concentrations of vitamin A and beta-carotene among adults in the United States.

    PubMed

    Ford, Earl S; Choi, Hyon K

    2013-12-01

    Our objective was to examine the cross-sectional associations between concentrations of vitamin A and beta-carotene, a major source of vitamin A, with concentrations of uric acid in a nationally representative sample of adults from the United States. We conducted a cross-sectional study using data from up to 10893 participants aged ≥ 20 years of National Health and Nutrition Examination Survey from 2001 to 2006. Concentrations of uric acid adjusted for numerous covariates increased from 305.8 μmol/L in the lowest quintile of vitamin A to 335.3 μmol/L in the highest quintile (p for linear trend <0.001). The prevalence ratio for hyperuricemia also increased progressively across quintiles of serum vitamin A reaching 1.82 (95% confidence interval [CI]: 1.52, 2.16; p for linear trend <0.001) in the top quintile in the maximally adjusted model. Adjusted mean concentrations of uric acid decreased progressively from quintile 1 (333.8 μmol/L) through quintile 4 of concentrations of beta-carotene and were similar for quintiles 4 (313.5 μmol/L) and 5 (313.8 μmol/L). Concentrations of beta-carotene were inversely associated with hyperuricemia (adjusted prevalence ratio comparing highest with lowest quintile = 0.61; 95% CI: 0.52, 0.72; p for linear trend <0.001). Concentrations of uric acid were significantly and positively associated with concentrations of vitamin A and inversely with concentrations of beta-carotene. These cross-sectional findings require confirmation with experimental studies of vitamin A and beta-carotene supplementation.

  10. Acid-responsive properties of fibrils from heat-induced whey protein concentrate.

    PubMed

    Xu, Hong-Hua; Wang, Jing; Dong, Shi-Rong; Cheng, Wen; Kong, Bao-Hua; Tan, Jun-Yan

    2016-08-01

    The heat-induced fibrils of whey protein concentrate (WPC) have demonstrated an acid-responsive property; that is, the fibrils went through formation-depolymerization-reformation as pH was adjusted to 1.8, 6.5, and back to 1.8. We investigated the microstructure, driving force, and thermal stability of 3.0% (wt) WPC nanofibrils adjusted between pH 6.5 and 1.8 twice. The results showed that the nanofibrils had acid-responsive properties and good thermal stability after reheating for 10h at 90°C and adjusting pH from 1.8 to 6.5 to 1.8. The content of WPC fibril aggregates was not much different with the prolongation of heating times during pH variation. Although the nanofibrils' structure could be destroyed only by changing the pH, the essence of this destruction might only form fiber fragments, polymers that would restore a fibrous structure upon returning to pH 1.8. A described model for the acid-responsive assembly of fibrils of WPC was proposed. The fibrils went through formation-depolymerization-reformation by weaker noncovalent interactions (surface hydrophobicity) as pH changed from 1.8 to 6.5 back to 1.8. However, the fibrils lost the acid-responsive properties because much more S-S (disulfide) formation occurred when the solution was adjusted to pH 6.5 and reheated. Meanwhile, fibrils still possessed acid-responsive properties when reheated at pH 1.8, and the content of fibrils slightly increased with a further reduction of α-helix structure.

  11. Effect of unsaturated fatty acids and triglycerides from soybeans on milk fat synthesis and biohydrogenation intermediates in dairy cattle.

    PubMed

    Boerman, J P; Lock, A L

    2014-11-01

    Increased rumen unsaturated fatty acid (FA) load is a risk factor for milk fat depression. This study evaluated if increasing the amount of unsaturated FA in the diet as triglycerides or free FA affected feed intake, yield of milk and milk components, and feed efficiency. Eighteen Holstein cows (132 ± 75 d in milk) were used in a replicated 3 × 3 Latin square design. Treatments were a control (CON) diet, or 1 of 2 unsaturated FA (UFA) treatments supplemented with either soybean oil (FA present as triglycerides; TAG treatment) or soybean FA distillate (FA present as free FA; FFA treatment). The soybean oil contained a higher concentration of cis-9 C18:1 (26.0 vs. 11.8 g/100g of FA) and lower concentrations of C16:0 (9.6 vs. 15.0 g/100g of FA) and cis-9,cis-12 C18:2 (50.5 vs. 59.1g/100g of FA) than the soybean FA distillate. The soybean oil and soybean FA distillate were included in the diet at 2% dry matter (DM) to replace soyhulls in the CON diet. Treatment periods were 21 d, with the final 4 d used for sample and data collection. The corn silage- and alfalfa silage-based diets contained 23% forage neutral detergent fiber and 17% crude protein. Total dietary FA were 2.6, 4.2, and 4.3% of diet DM for CON, FFA, and TAG treatments, respectively. Total FA intake was increased 57% for UFA treatments and was similar between FFA and TAG. The intakes of individual FA were similar, with the exception of a 24 g/d lower intake of C16:0 and a 64 g/d greater intake of cis-9 C18:1 for the TAG compared with the FFA treatment. Compared with CON, the UFA treatments decreased DM intake (1.0 kg/d) but increased milk yield (2.2 kg/d) and milk lactose concentration and yield. The UFA treatments reduced milk fat concentration, averaging 3.30, 3.18, and 3.11% for CON, FFA, and TAG treatments, respectively. Yield of milk fat, milk protein, and 3.5% fat-corrected milk remained unchanged when comparing CON with the UFA treatments. No differences existed in the yield of milk or milk

  12. Determination of component concentrations in mixtures of weak and strong acids and bases by linear algebraic methods.

    PubMed

    Ivaska, A; Nagypál, I

    1980-09-01

    A general expression for transforming potentiometric titration curves of mixtures of weak acids into a system of linear equations is derived. The solution of the linear equations gives directly the concentrations of the components. This linear transformation method is illustrated by the analysis of mixtures of weak acids with overlapping dissociation equilibria. The possible presence of a strong acid or strong base in the mixture can also be detected and its concentration simultaneously determined. The method can also be used for analysis of an ampholyte and solutions containing a weak acid and its conjugate base. For example a mixture of hydroxyacetic acid (pK approximately 3.6), acetic acid (pK approximately 4.6) and hydroxylamine hydrochloride (pK approximately 6) was analysed in the presence of strong acid with an average relative error of approximately 2%.

  13. Organic amendments increase soil solution phosphate concentrations in an acid soil: A controlled environment study

    SciTech Connect

    Schefe, C.R.; Patti, A.F.; Clune, T.S.; Jackson, R.

    2008-04-15

    Soil acidification affects at least 4 million hectares of agricultural land in Victoria, Australia. Low soil pH can inhibit plant growth through increased soluble aluminum (Al) concentrations and decreased available phosphorus (P). The addition of organic amendments may increase P availability through competition for P binding sites, solubilization of poorly soluble P pools, and increased solution pH. The effect of two organic amendments (lignite and compost) on P solubility in an acid soil was determined through controlled environment (incubation) studies. Three days after the addition of lignite and compost, both treatments increased orthophosphate and total P measured in soil solution, with the compost treatments having the greatest positive effect. Increased incubation time (26 days) increased soil solution P concentrations in both untreated and amended soils, with the greatest effect seen in total P concentrations. The measured differences in solution P concentrations between the lignite- and compost-amended treatments were likely caused by differences in solution chemistry, predominantly solution pH and cation dynamics. Soil amendment with lignite or compost also increased microbial activity in the incubation systems, as measured by carbon dioxide respiration. Based on the results presented, it is proposed that the measured increase in soil solution P with amendment addition was likely caused by both chemical and biological processes, including biotic and abiotic P solubilization reactions, and the formation of soluble organic-metal complexes.

  14. Preparation of monodisperse aqueous microspheres containing high concentration of l-ascorbic acid by microchannel emulsification.

    PubMed

    Khalid, Nauman; Kobayashi, Isao; Neves, Marcos A; Uemura, Kunihiko; Nakajima, Mitsutoshi; Nabetani, Hiroshi

    2015-01-01

    Monodisperse aqueous microspheres containing high concentrations of l-ascorbic acid with different concentrations of sodium alginate (Na-ALG) and magnesium sulfate (MgSO4) were prepared by using microchannel emulsification (MCE). The continuous phase was water-saturated decane containing a 5% (w/w) hydrophobic emulsifier. The flow rate of the continuous phase was maintained at 10 mL h(-1), whereas the pressure applied to the disperse phase was varied between 3 and 25 kPa. The disperse phase optimized for successfully generating aqueous microspheres included 2% (w/w) Na-ALG and 1% (w/w) MgSO4. At a higher MgSO4 concentration, the generated microspheres resulted in coalescence and subsequent bursting. At a lower MgSO4 concentration, unstable and polydisperse microspheres were obtained. The aqueous microspheres generated from the MCs under optimized conditions had a mean particle diameter (dav) of 14-16 µm and a coefficient of variation (CV) of less than 8% at the disperse phase pressures of 5-15 kPa.

  15. Changes in aggregation behavior of collagen molecules in solution with varying concentrations of acetic acid.

    PubMed

    Yang, Huan; Xu, Songcheng; Shen, Lirui; Liu, Wentao; Li, Guoying

    2016-11-01

    A critical aggregation concentration of 0.30-0.50mg/mL was previously obtained for type I collagen at 0.1M acetic acid (AA). In the present study, the aggregation behavior of collagen in solution (0.5mg/mL) in the presence of 0.1-2.0M AA was investigated. Circular dichroism showed that the three helix structure was maintained across the whole AA concentration range. However, the ratio of positive peak intensity over negative peak intensity varied depending on the conformational state of collagen aggregates. Ultra-sensitive differential scanning calorimetry revealed that transition temperatures Tm1 and Tm2 decreased by 8.35°C and 7.80°C, respectively, between 0.1M and 2.0M, indicating a possible relationship between the aggregation state and the thermal effect. The surrounding polarity of collagen molecules in solution containing pyrene was investigated by fluorescence spectroscopy, which demonstrated that disaggregation of collagen aggregates was enhanced with increasing AA concentration. This observation was correlated with changes in collagen fiber size observed by atomic force microscopy. Furthermore, collagen tyrosine residues were blue-shifted in an intrinsic fluorescence spectra, further indicating changes in aggregation behavior with increasing AA concentration. Finally, the dynamic response of collagen molecules to AA was analyzed by two-dimensional correlation fluorescence spectra.

  16. [Electricity generation using high concentration terephthalic acid solution by microbial fuel cell].

    PubMed

    Ye, Ye-Jie; Song, Tian-Shun; Xu, Yuan; Chen, Ying-Wen; Zhu, She-Min; Shen, Shu-Bao

    2009-04-15

    The high concentration terephthalic acid (TA) solution as the substrate of microbial fuel cell (MFC) was studied to generate electricity. The open circuit voltage was 0.54 V after inoculating for 210 h with anaerobic activated sludge, which proved that TA can be the substrate of microbial fuel cell to generate electricity. The influence of pH and substrate concentration on generating electricity was studied deeply. The voltage output of external resistance (R = 1,000 Omega) was the highest when pH was 8.0. It increased as the substrate concentration increasing and tended towards a maximum value. The maximum voltage output Umax was 0.5 V and Ks was 785.2 mg/L by Monod equation regression. When the substrate concentration (according to COD) was 4000 mg/L, the maximum power density was 96.3 mW/m2, coulomb efficiency was 2.66% and COD removal rate was 80.3%.

  17. Disruption of glucose homeostasis and induction of insulin resistance by elevated free fatty acids in human L02 hepatocytes.

    PubMed

    Wan, X-D; Yang, W-B; Xia, Y-Z; Wang, J-F; Lu, T; Wang, X-M

    2009-05-01

    Free fatty acids (FFA) have been implicated as an important causative link between obesity, insulin resistance, and Type 2 diabetes. However, the underlying mechanisms especially for FFA-mediated hepatic insulin resistance are not fully elucidated. Here, we investigated the impaired sites in insulin signaling pathways and mechanisms of insulin resistance induced by elevated FFA in L02 hepatocytes. L02 cells were cultured in Dulbecco's modified eagle medium containing various concentrations of palmitic acid (PA) for 24 h followed by 10(-7) mol/l insulin stimulation. In some experiments, cells were pre-treated with enzymatic inhibitor Wortmannin (10(-6) mol/l). Glucose levels in medium, cytosolic glycogen contents, and phosphoenolpyruvate carboxykinase (PEPCK) activity were measured. Protein level of insulin receptor substrate (IRS)-2 and phosphorylated Akt were detected by Western blot analysis. L02 cells treated with high levels of PA exhibited increased glucose levels, whereas hepatic glycogen contents were decreased in a dose-dependent manner as compared to the control cells. There was a significant attenuation of IRS- 2 protein expression in the cells cultured with PA, and Wortmannin intervention exhibited different IRS-2 protein level with or without PA treatment. In accordance with the reduced IRS-2 level, the insulin-stimulated phosphorylation of Akt was diminished in the PA-treated cells. Basal PEPCK activity and insulin- regulated PEPCK activity were overstimulated in the cells incubated with PA. These data indicate high levels of FFA can disrupt glucose homeostasis, inflict some defects in insulin signaling, and induce insulin resistance in L02 cells.

  18. Effect of dissolved oxygen concentration on iron efficiency: Removal of three chloroacetic acids.

    PubMed

    Tang, Shun; Wang, Xiao-mao; Mao, Yu-qin; Zhao, Yu; Yang, Hong-wei; Xie, Yuefeng F

    2015-04-15

    The monochloroacetic, dichloroacetic and trichloroacetic acid (MCAA, DCAA and TCAA) removed by metallic iron under controlled dissolved oxygen conditions (0, 0.75, 1.52, 2.59, 3.47 or 7.09 mg/L DO) was investigated in well-mixed batch systems. The removal of CAAs increased first and then decreased with increasing DO concentration. Compared with anoxic condition, the reduction of MCAA and DCAA was substantially enhanced in the presence of O2, while TCAA reduction was significantly inhibited above 2.59 mg/L. The 1.52 mg/L DO was optimum for the formation of final product, acetic acid. Chlorine mass balances were 69-102%, and carbon mass balances were 92-105%. With sufficient mass transfer from bulk to the particle surface, the degradation of CAAs was limited by their reduction or migration rate within iron particles, which were dependent on the change of reducing agents and corrosion coatings. Under anoxic conditions, the reduction of CAAs was mainly inhibited by the available reducing agents in the conductive layer. Under low oxic conditions, the increasing reducing agents and thin lepidocrocite layer were favorable for CAA dechlorination. Under high oxic conditions, the redundant oxygen competing for reducing agents and significant lepidocrocite growth became the major restricting factors. Various CAA removal mechanisms could be potentially applied to explaining the effect of DO concentration on iron efficiency for contaminant reduction in water and wastewater treatment.

  19. Estimates of late Quaternary mode and intermediate water silicic acid concentration in the Pacific Southern Ocean

    NASA Astrophysics Data System (ADS)

    Rousseau, Jonathon; Ellwood, Michael J.; Bostock, Helen; Neil, Helen

    2016-04-01

    The Southern Ocean plays a critical role in the exchange of carbon between the ocean and atmosphere over glacial-interglacial timescales. Hypotheses used to explain late Quaternary variations in atmospheric carbon dioxide (CO2) implicate changes in the nutrient dynamics and circulation of the Southern Ocean. Here we present silicon isotope (δ30Si) records of late Quaternary sponges and diatoms from the NZ-sector of the Southern Ocean. Analysis of our sponge δ30Si records strongly suggests that the silicic acid concentration at mode and intermediate depths was higher during the LGM and the deglacial period compared to the present day. Our diatom δ30Si record suggests biological productivity near of the Polar Front was greater during the deglacial period, but not significantly different during the LGM compared to the present day. Taking our dataset in context with other regional paleoceanographic records, we interpret the predicted elevation in LGM and deglacial silicic acid concentration to reflect a shoaling of water masses during the LGM and 'leakage' of excess Southern Ocean dissolved silicon during the deglacial period.

  20. Preparation of Rutile from Ilmenite Concentrate Through Pressure Leaching with Hydrochloric Acid

    NASA Astrophysics Data System (ADS)

    Xiang, Junyi; Liu, Songli; Lv, Xuewei; Bai, Chenguang

    2017-04-01

    Take into account the fact that the natural rutile utilized for the production of titanium dioxide pigment through chloride process is desperately lacking worldwide especially in China, an attempt was exploited for extracting synthetic rutile from Yunnan ilmenite concentrate with hydrochloric acid pressure leaching process. The leaching parameters for one step leaching process were investigated. The results shown that the optimum condition is leaching temperature of 413 K (140 °C), acid concentration of 20 pct HCl, leaching time of 4 hours and liquid/solid mass ratio of 8:1. A two steps leaching process was also suggested to reutilize the leaching liquor which with a high content of HCl. The results showed that the content of HCl decreased from 135 to 75 g/L, total iron increased from 44.5 g/L to about 87.6 g/L, and the liquid/solid mass ratio decreased to 5:1 with a two steps leaching process. The leaching product produced through a two steps leaching process shows a pure golden red with a high content of titanium (92.65 pct TiO2), a relatively low content of calcium (0.10 pct CaO) and magnesium (0.12 pct MgO), but high content of silicon (5.72 pct SiO2).

  1. Preparation of Rutile from Ilmenite Concentrate Through Pressure Leaching with Hydrochloric Acid

    NASA Astrophysics Data System (ADS)

    Xiang, Junyi; Liu, Songli; Lv, Xuewei; Bai, Chenguang

    2016-12-01

    Take into account the fact that the natural rutile utilized for the production of titanium dioxide pigment through chloride process is desperately lacking worldwide especially in China, an attempt was exploited for extracting synthetic rutile from Yunnan ilmenite concentrate with hydrochloric acid pressure leaching process. The leaching parameters for one step leaching process were investigated. The results shown that the optimum condition is leaching temperature of 413 K (140 °C), acid concentration of 20 pct HCl, leaching time of 4 hours and liquid/solid mass ratio of 8:1. A two steps leaching process was also suggested to reutilize the leaching liquor which with a high content of HCl. The results showed that the content of HCl decreased from 135 to 75 g/L, total iron increased from 44.5 g/L to about 87.6 g/L, and the liquid/solid mass ratio decreased to 5:1 with a two steps leaching process. The leaching product produced through a two steps leaching process shows a pure golden red with a high content of titanium (92.65 pct TiO2), a relatively low content of calcium (0.10 pct CaO) and magnesium (0.12 pct MgO), but high content of silicon (5.72 pct SiO2).

  2. Efficient treatment of perfluorohexanoic acid by nanofiltration followed by electrochemical degradation of the NF concentrate.

    PubMed

    Soriano, Álvaro; Gorri, Daniel; Urtiaga, Ane

    2017-04-01

    The present study was aimed at the development of a strategy for removing and degrading perfluorohexanoic acid (PFHxA) from industrial process waters at concentrations in the range 60-200 mg L(-1). The treatment train consisted of nanofiltration (NF) separation followed by electrochemical degradation of the NF concentrate. Using a laboratory-scale system and working in the total recirculation mode, the DowFilm NF270 membrane provided PFHxA rejections that varied in the range 96.6-99.4% as the operating pressure was increased from 2.5 to 20 bar. The NF operation in concentration mode enabled a volume reduction factor of 5 and increased the PFHxA concentration in the retentate to 870 mg L(-1). Results showed that the increase in PFHxA concentration and the presence of calcium sulfate salts did not induce irreversible membrane fouling. The NF retentate was treated in a commercial undivided electrochemical cell provided with two parallel flow-by compartments separated by bipolar boron doped diamond (BDD) electrode, BDD counter anode, and counter cathode. Current densities ranging from 20 to 100 A m(-2) were examined. The electrochemical degradation rate of PFHxA reached 98% and was accompanied by its efficient mineralization, as the reduction of total organic carbon was higher than 95%. Energy consumption, which was 15.2 kWh m(-3) of treated NF concentrate, was minimized by selecting operation at 50 A m(-2). While most of the previous research on the treatment of perfluoroalkyl substances (PFASs) focused on the removal of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), these compounds have been phased out by chemical manufacturers. Our findings are relevant for the treatment of PFHxA, which appears to be one of the present alternatives to long-chain PFASs thanks to its lower bioaccumulative potential than PFOA and PFOS. However, PFHxA also behaves as a persistent pollutant. Moreover, our results highlight the potential of combining

  3. Determination of tolerable fatty acids and cholera toxin concentrations using human intestinal epithelial cells and BALB/c mouse macrophages.

    PubMed

    Tamari, Farshad; Tychowski, Joanna; Lorentzen, Laura

    2013-05-30

    The positive role of fatty acids in the prevention and alleviation of non-human and human diseases have been and continue to be extensively documented. These roles include influences on infectious and non-infectious diseases including prevention of inflammation as well as mucosal immunity to infectious diseases. Cholera is an acute intestinal illness caused by the bacterium Vibrio cholerae. It occurs in developing nations and if left untreated, can result in death. While vaccines for cholera exist, they are not always effective and other preventative methods are needed. We set out to determine tolerable concentrations of three fatty acids (oleic, linoleic and linolenic acids) and cholera toxin using mouse BALB/C macrophages and human intestinal epithelial cells, respectively. We solubilized the above fatty acids and used cell proliferation assays to determine the concentration ranges and specific concentrations of the fatty acids that are not detrimental to human intestinal epithelial cell viability. We solubilized cholera toxin and used it in an assay to determine the concentration ranges and specific concentrations of cholera toxin that do not statistically decrease cell viability in BALB/C macrophages. We found the optimum fatty acid concentrations to be between 1-5 ng/μl, and that for cholera toxin to be < 30 ng per treatment. This data may aid future studies that aim to find a protective mucosal role for fatty acids in prevention or alleviation of cholera infections.

  4. Transport, distribution space and intracellular concentration of the anti-inflammatory drug niflumic acid in the perfused rat liver.

    PubMed

    Kelmer-Bracht, A M; Ishii-Iwamoto, E L; Bracht, A

    1993-05-05

    Transport and distribution space of niflumic acid in the perfused rat liver were investigated employing the multiple-indicator dilution technique with constant infusion of the drug (step input). Niflumic acid permeated the cell membrane in both directions at very high rates and its distribution in the cellular space was flow-limited; at least at 37 degrees, the rates of influx and efflux could not be measured. Dissociation of the niflumic acid-albumin complex also occurred at very high rates. The apparent space of distribution of niflumic acid in the liver depended on the concentration of the drug and varied between 4.37 (1 mM) and 43.5 (10 microM) times the water space; even with 90% extracellular binding to albumin, the apparent space of distribution of niflumic acid was 5.1 times greater than the water space. The high apparent spaces of distribution reflected the high intracellular concentrations. The ratio of intracellular bound plus free concentration to the extracellular bound plus free concentration (Ci/Ce) varied between 6.62 (1 mM portal niflumic acid) and 71.0 (10 microM portal niflumic acid). Metabolic transformation depended on the concentration of the free form. Intracellular binding is probably the major reason for the high concentration of the drug in the hepatic tissue.

  5. Influence of deficit irrigation strategies on fatty acid and tocopherol concentration of almond (Prunus dulcis).

    PubMed

    Zhu, Ying; Taylor, Cathy; Sommer, Karl; Wilkinson, Kerry; Wirthensohn, Michelle

    2015-04-15

    The effects of deficit irrigation on almond fatty acid and tocopherol levels were studied in a field trial. Mature almond trees were subjected to three levels of deficit irrigation (85%, 70% and 55% of potential crop evapotranspiration (ETo), as well as control (100% ETo) and over-irrigation (120% ETo) treatments. Two deficit irrigation strategies were employed: regulated deficit irrigation (RDI) and sustained deficit irrigation (SDI). Moderate deficit irrigation (85% RDI and 85% SDI) had no detrimental impact on almond kernel lipid content, but severe and extreme deficiencies (70% and 55%) influenced lipid content. Unsaturated fatty acid (USFA) and saturated fatty acid (SFA) contents fluctuated under these treatments, the oleic/linoleic ratio increased under moderate water deficiency, but decreased under severe and extreme water deficiency. Almond tocopherols concentration was relatively stable under deficit irrigation. The variation between years indicated climate has an effect on almond fruit development. In conclusion it is feasible to irrigate almond trees using less water than the normal requirement, without significant loss of kernel quality.

  6. Prospects for cleaning ash in the acidic effluent from bioleaching of sulfidic concentrates.

    PubMed

    Paul, M; Sandström, A; Paul, J

    2004-01-02

    Leaching of ashes in sulfuric acid (pH 1.0, liquid-to-solid (L/S) ratio 10:1, 25 degrees C) has been characterized with respect to the neutralizing capacity and the dissolution of dominant ions and trace elements. The conditions mimic the oxidation stage of a biohydrometallurgical process for base metal production from sulfidic mineral concentrates. Direct acid leaching of ash, integrated with this metallurgical process, offers a feasible route to the sustainable handling of metal-rich ashes. The treated ash will be deposited together with the inert mineral residue. Cd, Co, Cu, Ni and Zn are effectively leached and can be recovered utilizing existing hydrometallurgical technology, but the recovery of other readily dissolved metals, notably Mn, U and V, requires that additional steps are implemented. We make two recommendations for industrial processes. The first is to replace limestone with ash from biofuels, except peat, for pH control in biohydrometallurgical processing. This requires a modest increase of fresh alkali compared with limestone. The second is to implement sulfuric acid leaching of fly ash from the combustion of solid waste and other metal-rich fuels (used wood, tires), thereby avoiding costly ash-deposits. There is a significant economic incentive for these changes, since no costly ash-deposits and less limestone will be needed.

  7. Effect of acute bile acid pool depletion on total and ionized calcium concentrations in human bile.

    PubMed

    Gleeson, D; Murphy, G M; Dowling, R H

    1995-04-01

    Although calcium salts are important components of gallstones, there are few data on the total and ionized calcium content of human bile. Therefore, in 14 fasting T-tube patients studied 7-11 days after cholecystectomy, we measured bile flow, bile acid [BA], total [CaTOT] and free ionized [Ca++] calcium concentrations, in 20-30 min bile collections during acute BA pool depletion induced by 6-8 h of continuous bile drainage. During washout of the BA pool there were parallel falls in bile flow, BA output and total calcium output (correlation coefficients ranging from 0.59 to 0.99; P < 0.02-0.001). In 12 of the 14 patients, [CaTOT] also fell (from 1.84 +/- 0.29 to 1.32 +/- 0.34 mmol L-1) in parallel with [BA] (from 34.0 +/- 14.0 to 8.2 +/- 8.0 mmol L-1; r = 0.75-0.98; P < 0.005). In contrast, biliary [Ca++] remained virtually unchanged. These data suggest that the BAs are linked to the bound, rather than to the free, ionized, fraction of biliary calcium, which is consistent with in vivo calcium binding by BAs. A model is proposed in which BA-induced biliary calcium secretion results from (i) bile acid-induced water flow via solvent drag; and (ii) calcium binding in the bile canaliculus by bile acids, which induces paracellular diffusion of Ca++, thereby maintaining [Ca++] independent of [BA].

  8. Aspartic acid concentrations in coral skeletons as recorders of past disturbances of metabolic rates

    NASA Astrophysics Data System (ADS)

    Gupta, Lallan P.; Suzuki, Atsushi; Kawahata, Hodaka

    2006-11-01

    The composition of total hydrolysable amino acids (THAAs) in a skeleton of the coral Porites australiensis, collected from Ishigaki Island, Japan, was examined in order to determine whether amino acids (AA) can be used as biomarkers of past changes in coral physiology (metabolism). Micro-samples, corresponding to a time resolution of 1 month, were collected along the growth axis of the coral. Of the 20 AAs analyzed, aspartic acid (Asp) was the most abundant, and its mole concentration relative to the sum of all other AAs (mole%Asp) showed a clear seasonal pattern of low content during winters and high during summers. A growth disturbance in the coral skeleton during 1988 1990, shown by X-ray scans and oxygen and carbon stable isotope data, was marked by a high mole%Asp ratio. Variability in carbon isotope data has often been attributed to metabolic effects, or changes in the isotopic composition of seawater, or both. The changes in mole%Asp shown here suggest that metabolic effects are mainly responsible for sharp changes in carbon isotope profiles during periods of growth disturbance.

  9. Bioavailability of zinc to rats from defatted soy flour, acid-precipitated soy concentrate and neutralized soy concentrate as determined by intrinsic and extrinsic labeling techniques

    SciTech Connect

    Ketelsen, S.M.; Stuart, M.A.; Weaver, C.M.; Forbes, R.M.; Erdman, J.W. Jr.

    1984-03-01

    The bioavailability of 65Zn from intrinsically and extrinsically labeled soy flour, acid-precipitated soy concentrate and neutralized soy concentrate was evaluated in rats. Weanling rats were fed marginally zinc-deficient diets, providing 8 ppm zinc from one of these three soy products, for 7 days. The rats then received a radioactively labeled test meal, identical in composition to the previous diet except that the soy product was either intrinsically or extrinsically labeled with 65Zn. After the test meal the rats were again fed diets the same as those consumed prior to the test meal. Whole-body retention of 65Zn at 24 hours and 12 days as well as 65Zn retained in tibias of rats given meals containing neutralized concentrate-based meals was significantly lower than for rats given meals containing the soy flour or acid-precipitated concentrate. In addition, retention of 65Zn from the extrinsically labeled acid-precipitated concentrate-based meal was significantly higher than from the same product intrinsically labeled. These findings confirm the results of previous feeding studies from which it was suggested that neutralization of soy protein concentrates reduces zinc bioavailability to the rat. In addition, the results are taken to suggest that experimental conditions may influence the validity of the extrinsic labeling technique for zinc.

  10. Detailed Dimethylacetal and Fatty Acid Composition of Rumen Content from Lambs Fed Lucerne or Concentrate Supplemented with Soybean Oil

    PubMed Central

    Alves, Susana P.; Santos-Silva, José; Cabrita, Ana R. J.; Fonseca, António J. M.; Bessa, Rui J. B.

    2013-01-01

    Lipid metabolism in the rumen is responsible for the complex fatty acid profile of rumen outflow compared with the dietary fatty acid composition, contributing to the lipid profile of ruminant products. A method for the detailed dimethylacetal and fatty acid analysis of rumen contents was developed and applied to rumen content collected from lambs fed lucerne or concentrate based diets supplemented with soybean oil. The methodological approach developed consisted on a basic/acid direct transesterification followed by thin-layer chromatography to isolate fatty acid methyl esters from dimethylacetal, oxo- fatty acid and fatty acid dimethylesters. The dimethylacetal composition was quite similar to the fatty acid composition, presenting even-, odd- and branched-chain structures. Total and individual odd- and branched-chain dimethylacetals were mostly affected by basal diet. The presence of 18∶1 dimethylacetals indicates that biohydrogenation intermediates might be incorporated in structural microbial lipids. Moreover, medium-chain fatty acid dimethylesters were identified for the first time in the rumen content despite their concentration being relatively low. The fatty acids containing 18 carbon-chain lengths comprise the majority of the fatty acids present in the rumen content, most of them being biohydrogenation intermediates of 18∶2n−6 and 18∶3n−3. Additionally, three oxo- fatty acids were identified in rumen samples, and 16-O-18∶0 might be produced during biohydrogenation of the 18∶3n−3. PMID:23484024

  11. Addition of formic acid or starter cultures to liquid feed. Effect on pH, microflora composition, organic acid concentration and ammonia concentration.

    PubMed

    Canibe, N; Miquel, N; Miettinen, H; Jensen, B B

    2001-01-01

    Some of the charateristics of good quality fermented liquid feed (FLF) are low pH, high numbers of lactic acid bacteria, and low numbers of enterobacteria. In order to test strategies to avoid a proliferation of enterobacteria during the initial phase of FLF elaboration, two in vitro studies were carried out. Addition of various doses of formic acid or two different starter cultures were tested. Adding 0.1% formic acid or L. plantarum VTT E-78076 to the liquid feed seemed to be addecuate ways of inhibiting the growth of enterobacteria, without depleting the growth of lactic acid bacteria.

  12. Underestimation of pyruvic acid concentrations by fructose and cysteine in 2,4-dinitrophenylhydrazine-mediated onion pungency test.

    PubMed

    Yoo, Kil Sun; Lee, Eun Jin; Patil, Bhimanagouda S

    2011-10-01

    Onion pungency has been routinely measured by determining pyruvic acid concentration in onion juice by reacting with 2,4-dinitrophenylhydrazine (DNPH) since 1961. However, the absorbency of the color adduct of the reaction rapidly decreased in onion samples as compared to that of the pyruvic acid standards, resulting in underestimations of the pyruvic acid concentrations. By measuring the absorbency at 1 min, we have demonstrated that accuracy could be substantially improved. As a continuation, the causes of degradation of the color adduct after the reaction and pyruvic acid itself before the reaction were examined in this study. Alliinase action in juice (fresh or cooked) and bulb colors did not influence the degradation. Some organic acids indigenously found in onion, such as ascorbic acid, proline, and glutamic acid, did not reduce the absorbency. However, fructose within the onion juice or supplemented caused the degradation of the color adduct, whereas sucrose and glucose had a lesser effect. Degradation rates increased proportionally as fructose concentrations increased up to 70 mg/mL. Cysteine was found to degrade the pyruvic acid itself before the pyruvic acid could react with DNPH. Approximately 90% of the pyruvic acid was degraded after 60 min in samples of 7 mM pyruvic acid supplemented with 10 mg/mL cysteine. Spectral comparisons of onion juice containing fructose naturally and pyruvic acid solution with supplemented fructose indicated identical patterns and confirmed that the color-adduct degradation was caused by fructose. Our study elucidated that fructose, a major sugar in onion juice, caused the degradation of color adduct in the onion pungency test and resulted in underestimation of the pyruvic acid concentration.

  13. Water-lactose behavior as a function of concentration and presence of lactic acid in lactose model systems.

    PubMed

    Wijayasinghe, Rangani; Vasiljevic, Todor; Chandrapala, Jayani

    2015-12-01

    The presence of high amounts of lactic acid in acid whey restricts its ability to be further processed because lactose appears to remain in its amorphous form. A systematic study is lacking in this regard especially during the concentration step. Hence, the main aim of the study was to establish the structure and behavior of water molecules surrounding lactose in the presence of 1% (wt/wt) lactic acid at a concentration up to 50% (wt/wt). Furthermore, the crystallization nature of freeze-dried lactose with or without lactic acid was established using differential scanning calorimetry and Fourier transform infrared spectroscopy. Two mechanisms were proposed to describe the behavior of water molecules around lactose molecules during the concentration of pure lactose and lactose solutions with lactic acid. Pure lactose solution exhibited a water evaporation enthalpy of ~679 J·g(-1), whereas lactose+ lactic acid solution resulted in ~965 J·g(-1) at a 50% (wt/wt) concentration. This indicates a greater energy requirement for water removal around lactose in the presence of lactic acid. Higher crystallization temperatures were observed with the presence of lactic acid, indicating a delay in crystallization. Furthermore, less crystalline lactose (~12%) was obtained in the presence of lactic acid, indicating high amorphous nature compared with pure lactose where ~50% crystallinity was obtained. The Fourier transform infrared spectra revealed that the strong hydration layer consisting lactic acid and H3O(+) ions surrounded lactose molecules via strong H bonds, which restricted water mobility, induced a change in structure of lactose, or both, creating unfavorable conditions for lactose crystallization. Thus, partial or complete removal of lactic acid from acid whey may be the first step toward improving the ability of acid whey to be processed.

  14. Pickled egg production: effect of brine acetic acid concentration and packing conditions on acidification rate.

    PubMed

    Acosta, Oscar; Gao, Xiaofan; Sullivan, Elizabeth K; Padilla-Zakour, Olga I

    2014-05-01

    U.S. federal regulations require that acidified foods must reach a pH of 4.6 or lower within 24 h of packaging or be kept refrigerated until then. Processes and formulations should be designed to satisfy this requirement, unless proper studies demonstrate the safety of other conditions. Our objective was to determine the effect of brine acetic acid concentration and packing conditions on the acidification rate of hard-boiled eggs. Eggs were acidified (60/40 egg-to-brine ratio) at various conditions of brine temperature, heat treatment to filled jars, and postpacking temperature: (i) 25 °C/none/25 °C (cold fill), (ii) 25 °C/none/2 °C (cold fill/refrigerated), (iii) 85 °C/none/25 °C (hot fill), and (iv) 25 °C/100 °C for 16 min/25 °C (water bath). Three brine concentrations were evaluated (7.5, 4.9, and 2.5% acetic acid) and egg pH values (whole, yolk, four points within egg) were measured from 4 to 144 h, with eggs equilibrating at pH 3.8, 4.0, and 4.3, respectively. Experiments were conducted in triplicate, and effects were considered significant when P < 0.05. Multiple linear regression analysis was conducted to evaluate the effect on pH values at the center of the yolk. Regression analysis showed that brine concentration of 2.5% decreased the acidification rate, while packing conditions of the hot fill trial increased it. Inverse prediction was used to determine the time for the center of the yolk and the total yolk to reach a pH value of 4.6. These results demonstrate the importance of conducting acidification studies with proper pH measurements to determine safe conditions to manufacture commercially stable pickled eggs.

  15. Gastric HCO3- secretion induced by mucosal acidification: different mechanisms depending on acid concentration.

    PubMed

    Aihara, Eitaro; Hayashi, Masamune; Sasaki, Yoko; Takeuchi, Koji

    2005-01-01

    We compared the HCO3- secretory responses induced by mucosal acidification at different HCl concentrations (100 and 200 mM HCl) in the rat stomach. Under urethane anesthesia, the stomach was mounted on an ex vivo chamber and perfused with saline under inhibition of acid secretion by omeprazole (60 mg/kg, i.p.). TheHCO3- secretion was measured at pH 7.0 using a pH-stat method and by adding 2 mM HCl. The acidification was performed by exposure of the mucosa to 100 mMor 200 mM HCl for 10 min. The secretion of HCO3- was increased by acidification of the mucosa at both 100 and 200 mM of HCl, and the maximal HCO3- response was 1.5-times greater at the latter concentration. The HCO3- responses induced by 100 and 200 mM HCl were both totally inhibited by prior administration of indomethacin, an inhibitor of prostaglandin (PG) production. The HCO3- stimulatory effect of 200 mM HCl was also significantly attenuated by pre-treatment with N(G)-nitro L-arginine methyl ester (L-NAME), the inhibitor of nitric oxide (NO) synthase, as well as chemical ablation of capsaicin-sensitive afferent neurons, whereas that of 100 mM HCl was affected by neither of these treatments. We conclude that the mucosal acidification stimulates gastric HCO3- secretion in different mechanisms, depending on the concentration of acid; the response caused by 100 mM HCl is mediated only by PGs, while that caused by 200 mM HCl is mediated by both capsaicin-sensitive afferent neurons and NO, in addition to PGs.

  16. n-Alkanoic monocarboxylic acid concentrations in urban and rural aerosols: Seasonal dependence and major sources

    NASA Astrophysics Data System (ADS)

    Shannigrahi, Ardhendu S.; Pettersson, Jan B. C.; Langer, Sarka; Arrhenius, Karine; Hagström, Magnus; Janhäll, Sara; Hallquist, Mattias; Pathak, Ravi Kant

    2014-06-01

    We report new data on the abundance and distribution of n-monocarboxylic acids (n-MCAs) in fine- and coarse-mode aerosols in rural and urban areas of Sweden, and determine their possible sources. Overall, C6-C16n-MCAs accounted for ~ 0.5-1.2% of the total PM10 (particulate matter ≤ 10 μm) mass. In general, the C12-C16 fraction was the most abundant (> 75%), with the exception of wintertime samples from a rural site, where C6-C11 acids accounted for 65% of the total C6-C16n-MCA mass. Positive matrix factorization analysis revealed four major sources of n-MCAs: traffic emissions, wood combustion, microbial activity, and a fourth factor that was dominated by semi-volatile n-MCAs. Traffic emissions were important in the urban environment in both seasons and at the rural site during winters, and were a major source of C9-C11 acids. Wood combustion was a significant source at urban sites during the winter and also to some extent at the rural site in both seasons. This is consistent with the use of wood for domestic heating but may also be related to meat cooking. Thus, during the winter, traffic, wood combustion and microbial activity were all important sources in the urban environment, while traffic was the dominant source at the rural site. During the summer, there was considerable day-to-day variation in n-MCA concentrations but microbial activity was the dominant source. The semi-volatile low molecular weight C6-C8 acids accounted for a small (~ 5-10%) fraction of the total mass of n-MCAs. This factor is unlikely to be linked to a single source and its influence instead reflects the partitioning of these compounds between the gas and particle phases. This would explain their greater contribution during the winter.

  17. Granulocyte colony-stimulating factor (G-CSF): A saturated fatty acid-induced myokine with insulin-desensitizing properties in humans

    PubMed Central

    Ordelheide, Anna-Maria; Gommer, Nadja; Böhm, Anja; Hermann, Carina; Thielker, Inga; Machicao, Fausto; Fritsche, Andreas; Stefan, Norbert; Häring, Hans-Ulrich; Staiger, Harald

    2016-01-01

    Objective Circulating long-chain free fatty acids (FFAs) are important metabolic signals that acutely enhance fatty acid oxidation, thermogenesis, energy expenditure, and insulin secretion. However, if chronically elevated, they provoke inflammation, insulin resistance, and β-cell failure. Moreover, FFAs act via multiple signaling pathways as very potent regulators of gene expression. In human skeletal muscle cells differentiated in vitro (myotubes), we have shown in previous studies that the expression of CSF3, the gene encoding granulocyte colony-stimulating factor (G-CSF), is markedly induced upon FFA treatment and exercise. Methods and results We now report that CSF3 is induced in human myotubes by saturated, but not unsaturated, FFAs via Toll-like receptor 4-dependent and -independent pathways including activation of Rel-A, AP-1, C/EBPα, Src, and stress kinases. Furthermore, we show that human adipocytes and myotubes treated with G-CSF become insulin-resistant. In line with this, a functional polymorphism in the CSF3 gene affects adipose tissue- and whole-body insulin sensitivity and glucose tolerance in human subjects with elevated plasma FFA concentrations. Conclusion G-CSF emerges as a new player in FFA-induced insulin resistance and thus may be of interest as a target for prevention and treatment of type 2 diabetes. PMID:27069870

  18. THE EFFECTS OF DIFFERENT SAMPLE CONCENTRATIONS ON THE STRUCTURE OF MICROBIAL COMMUNITIES USING PHOSPHOLIPID FATTY ACID ANALYSIS

    EPA Science Inventory

    Phospholipid fatty acid (PLFA) analysis is a powerful tool for determination of microbial community structures in soils and sediments. However, accurate determination of total microbial biomass and structure of the microbial community may be dependent on the concentration of the...

  19. A Common Polymorphism in HIBCH Influences Methylmalonic Acid Concentrations in Blood Independently of Cobalamin

    PubMed Central

    Molloy, Anne M.; Pangilinan, Faith; Mills, James L.; Shane, Barry; O’Neill, Mary B.; McGaughey, David M.; Velkova, Aneliya; Abaan, Hatice Ozel; Ueland, Per M.; McNulty, Helene; Ward, Mary; Strain, J.J.; Cunningham, Conal; Casey, Miriam; Cropp, Cheryl D.; Kim, Yoonhee; Bailey-Wilson, Joan E.; Wilson, Alexander F.; Brody, Lawrence C.

    2016-01-01

    Methylmalonic acid (MMA) is a by-product of propionic acid metabolism through the vitamin B12 (cobalamin)-dependent enzyme methylmalonyl CoA mutase. Elevated MMA concentrations are a hallmark of several inborn errors of metabolism and indicators of cobalamin deficiency in older persons. In a genome-wide analysis of 2,210 healthy young Irish adults (median age 22 years) we identified a strong association of plasma MMA with SNPs in 3-hydroxyisobutyryl-CoA hydrolase (HIBCH, p = 8.42 × 10−89) and acyl-CoA synthetase family member 3 (ACSF3, p = 3.48 × 10−19). These loci accounted for 12% of the variance in MMA concentration. The most strongly associated SNP (HIBCH rs291466; c:2T>C) causes a missense change of the initiator methionine codon (minor-allele frequency = 0.43) to threonine. Surprisingly, the resulting variant, p.Met1?, is associated with increased expression of HIBCH mRNA and encoded protein. These homozygotes had, on average, 46% higher MMA concentrations than methionine-encoding homozygotes in young adults with generally low MMA concentrations (0.17 [0.14–0.21] μmol/L; median [25th–75th quartile]). The association between MMA levels and HIBCH rs291466 was highly significant in a replication cohort of 1,481 older individuals (median age 79 years) with elevated plasma MMA concentrations (0.34 [0.24–0.51] μmol/L; p = 4.0 × 10−26). In a longitudinal study of 185 pregnant women and their newborns, the association of this SNP remained significant across the gestational trimesters and in newborns. HIBCH is unique to valine catabolism. Studies evaluating flux through the valine catabolic pathway in humans should account for these variants. Furthermore, this SNP could help resolve equivocal clinical tests where plasma MMA values have been used to diagnose cobalamin deficiency. PMID:27132595

  20. Impact of confinement on proteins concentrated in lithocholic acid based organic nanotubes.

    PubMed

    Lu, Qin; Kim, Youngchan; Bassim, Nabil; Collins, Greg E

    2015-09-15

    Organic nanotubes form in aqueous solution near physiological pH by self-assembly of lithocholic acid (LCA) with inner diameters of 20-40nm. The encapsulation of enhanced green fluorescent protein (eGFP) and resultant confinement effect for eGFP within these nanotubes is studied via confocal microscopy. Timed release rate studies of eGFP encapsulated in LCA nanotubes and fluorescence recovery after photobleaching (FRAP) indicate that the diffusive transport of eGFP out of and/or within the nanotubes is very slow, in contrast to the rapid introduction of eGFP into the nanotubes. By encapsulating two fluorescent proteins in LCA nanotubes, eGFP and mCherry, as a fluorescence resonance energy transfer (FRET) pair, the FRET efficiencies are determined using FRET imaging microscopy at three different protein concentrations with a fixed donor-to-acceptor ratio of 1:1. Förster theory reveals that the proteins are spatially separated by 4.8-7.2nm in distance inside these nanotubes. The biomimetic nanochannels of LCA nanotubes not only afford a confining effect on eGFP that results in enhanced chemical and thermal stability under conditions of high denaturant concentration and temperature, but also function as protein concentrators for enriching protein in the nanochannels from a diluted protein solution by up to two orders of magnitude.

  1. Effects of allopurinol on uric acid concentrations, xanthine oxidoreductase activity and oxidative stress in broiler chickens.

    PubMed

    Carro, M D; Falkenstein, E; Radke, W J; Klandorf, H

    2010-01-01

    The purpose of this study was to determine the effects of allopurinol (AL) on xanthine oxidoreductase (XOR) activity and uric acid (UA) levels in chickens. Thirty 5-week-old broilers were divided into three groups and fed 0 (control), 25 (AL25) or 50 (AL50) mg AL per kg of body mass for 5 weeks. Chicks were weighed twice weekly and leukocyte oxidative activity (LOA) and plasma purine levels were determined weekly in five birds per group. Chicks were sacrificed after 2 or 5 weeks, and samples from tissues were taken for analysis of XOR activity. Plasma UA concentrations were lower (P<0.001) and xanthine and hypoxanthine concentrations were greater (P<0.001) in AL25 and AL50 birds compared to controls, whereas no differences (P=0.904) were detected in allantoin concentrations. By week 5, body mass was reduced (P<0.001) to 84.0 and 65.1% of that in controls for AL25 and AL50 broilers, respectively, and LOA was 4.1 times greater (P<0.05) in AL25 compared to control birds. Liver XOR activity was increased by 1.1 and 1.2 times in AL25 and AL50 birds, but there was no change (P>0.05) in XOR activity in the pancreas and intestine. These results suggest that AL effect on XOR activity is tissue dependent.

  2. Effect of pH, substrate and free nitrous acid concentrations on ammonium oxidation rate.

    PubMed

    Jiménez, E; Giménez, J B; Seco, A; Ferrer, J; Serralta, J

    2012-11-01

    Respirometric techniques have been used to determine the effect of pH, free nitrous acid (FNA) and substrate concentration on the activity of the ammonium oxidizing bacteria (AOB) present in an activated sludge reactor. With this aim, bacterial activity has been measured at different pH values (ranging from 6.2 to 9.7), total ammonium nitrogen concentrations (ranging from 0.1 to 10 mg TAN L(-1)) and total nitrite concentrations (ranging from 3 to 43 mg NO(2)-NL(-1)). According to the results obtained, the most appropriate kinetic expression for the growth of AOB in activated sludge reactors has been established. Substrate half saturation constant and FNA and pH inhibition constants have been obtained by adjusting model predictions to experimental results. Different kinetic parameter values and different Monod terms should be used to model the growth of AOB in activated sludge processes and SHARON reactors due to the different AOB species that predominate in both systems.

  3. Long-term variations of folic acid concentrations in the Northern Adriatic.

    PubMed

    Plavsić, Marta

    2004-08-01

    Folic acid (FA), which belongs to B-group vitamins has recently been recognized as possible nutrient for some phytoplankton species (a diatom Phaeodactylum tricornutum). The beneficial role of FA in human health is widely documented. In some countries food fortification with FA has already become mandatory. FA is also used under commercial name of Dosfolat for the treatment of industrial and domestic wastewaters. This is an exploratory study on seasonal and depth variability of FA concentrations in the Northern Adriatic Sea (station 101-max depth 30 m, under the Po River influence). Seawater samples were analysed in the period from February 1998 to February 2003 based on monthly determinations. Those preliminary findings showed that in the upper layer (10 m) FA concentrations were in the range from 0.1 to 28 nM. In the lower layer (20-30 m) FA concentrations were in the range from 0.1 to 12 nM. It was found that phytoplankton and microorganisms which are responsible for the production of FA in the Northern Adriatic (Station 101) were situated at the depth from 5 to 10 m. The observed water column and seasonal distributions depended on a sensitive balance between the production and the consumption of FA.

  4. Postprandial concentrations of free and conjugated bile acids down the length of the normal human small intestine

    PubMed Central

    Northfield, T. C.; McColl, I.

    1973-01-01

    Small intestinal samples were obtained by intubation from multiple sites along the small intestine in 11 subjects with no known gastrointestinal disease eating a normal diet and at laparotomy in a further three subjects. Free (unconjugated) bile acids were consistently demonstrated in ileal samples, and occasionally in lower jejunal samples, by thin-layer chromatography, supplemented in some cases by gas/liquid chromatography and by infrared spectroscopy. The free bile acid concentration, measured enzymically following thin-layer chromatography, reached a maximum (1 mM) in the lower ileum, where it represented half the total bile acid concentration. Following ampicillin, the concentration of free bile acids decreased markedly, suggesting that they resulted from bacterial deconjugation; at the same time the total bile acid concentration increased, suggesting impaired absorption due to the reduced concentration of the more rapidly absorbed free bile acids. Our results indicate that the presence of free bile acids in lower jejunal and ileal samples is a normal finding, and cannot be taken as evidence of abnormal bacterial overgrowth. They also suggest that bacterial deconjugation at these sites may be a factor contributing to the remarkable efficiency of bile salt reabsorption. ImagesFig 2 PMID:4729918

  5. Serum uric acid concentrations and SLC2A9 genetic variation in Hispanic children: The Viva La Familia Study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Elevated concentrations of serum uric acid are associated with increased risk of gout and renal and cardiovascular diseases. Genetic studies in adults have consistently identified associations of solute carrier family 2, member 9 (SLC2A9), polymorphisms with variation in serum uric acid. However, it...

  6. Low unesterified:esterified eicosapentaenoic acid (EPA) plasma concentration ratio is associated with bipolar disorder episodes, and omega-3 plasma concentrations are altered by treatment

    PubMed Central

    Saunders, Erika FH; Reider, Aubrey; Singh, Gagan; Gelenberg, Alan J; Rapoport, Stanley I

    2015-01-01

    Objectives Omega (n)-3 and n-6 polyunsaturated fatty acids (PUFA) are molecular modulators of neurotransmission and inflammation. We hypothesized that plasma concentrations of n-3 PUFA would be lower and of n-6 PUFA higher in subjects with bipolar disorder (BD) compared to healthy controls (HC), and would correlate with symptom severity in subjects with BD, and that effective treatment would correlate with increased n-3 but lower n-6 PUFA levels. Additionally, we explored clinical correlations and group differences in plasma levels of saturated and monounsaturated fatty acids. Methods This observational, parallel group study compared biomarkers between HC (n = 31), and symptomatic subjects with BD (n = 27) when ill and after symptomatic recovery (follow-up). Plasma concentrations of five PUFA [linoleic acid (LA), arachidonic acid (AA), alpha-linolenic acid (ALA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA)], of two saturated fatty acids (palmitic acid and stearic acid) and of two monounsaturated fatty acids (palmitoleic acid, oleic acid) were measured in esterified (E) and unesterified (UE) forms. Calculated ratios included UE:E for the five PUFA, ratios of n-3 PUFA (DHA:ALA, EPA:ALA, EPA:DHA), and the ratio of n-6:n-3 AA:EPA. Comparisons of plasma fatty acid levels and ratios between BD and HC groups were made with Student t-tests, between the BD group at baseline and follow-up using paired t-tests. Comparison of categorical variables was performed using Chi-square tests. Pearson’s r was used for bivariate correlations with clinical variables, including depressive and manic symptoms, current panic attacks, and psychosis. Results UE EPA was lower in BD than HC, with a large effect size (Cohen’s d = 0.86, p < 0.002), however, it was not statistically significant after correction for multiple comparisons. No statistically significant difference was seen in any plasma PUFA concentration between BD and HC after Bonferroni correction for 40

  7. RNA-Seq analysis and targeted mutagenesis for improved free fatty acid production in an engineered cyanobacterium

    PubMed Central

    2013-01-01

    Background High-energy-density biofuels are typically derived from the fatty acid pathway, thus establishing free fatty acids (FFAs) as important fuel precursors. FFA production using photosynthetic microorganisms like cyanobacteria allows for direct conversion of carbon dioxide into fuel precursors. Recent studies investigating cyanobacterial FFA production have demonstrated the potential of this process, yet FFA production was also shown to have negative physiological effects on the cyanobacterial host, ultimately limiting high yields of FFAs. Results Cyanobacterial FFA production was shown to generate reactive oxygen species (ROS) and lead to increased cell membrane permeability. To identify genetic targets that may mitigate these toxic effects, RNA-seq analysis was used to investigate the host response of Synechococcus elongatus PCC 7942. Stress response, nitrogen metabolism, photosynthesis, and protein folding genes were up-regulated during FFA production while genes involved in carbon and hydrogen metabolisms were down-regulated. Select genes were targeted for mutagenesis to confirm their role in mitigating FFA toxicity. Gene knockout of two porins and the overexpression of ROS-degrading proteins and hypothetical proteins reduced the toxic effects of FFA production, allowing for improved growth, physiology, and FFA yields. Comparative transcriptomics, analyzing gene expression changes associated with FFA production and other stress conditions, identified additional key genes involved in cyanobacterial stress response. Conclusions A total of 15 gene targets were identified to reduce the toxic effects of FFA production. While single-gene targeted mutagenesis led to minor increases in FFA production, the combination of these targeted mutations may yield additional improvement, advancing the development of high-energy-density fuels derived from cyanobacteria. PMID:23919451

  8. Radionuclide concentrations in raw and purified phosphoric acids from Brazil and their processing wastes: implications for radiation exposures.

    PubMed

    da Conceição, Fabiano Tomazini; Antunes, Maria Lúcia Pereira; Durrant, Steven F

    2012-02-01

    Radionuclides from the U and Th natural series are present in alkaline rocks, which are used as feedstock in Brazil for the production of raw phosphoric acid, which can be considered as a NORM (naturally occurring radioactive material). As a result of the purification of raw phosphoric acid to food-grade phosphoric acid, two by-products are generated, i.e., solid and liquid wastes. Taking this into account, the main aim of this study was to evaluate the fluxes of natural radionuclide in the production of food-grade phosphoric acids in Brazil, to determine the radiological impact caused by ingestion of food-grade phosphoric acid, and to evaluate the solid waste environmental hazards caused by its application in crop soils. Radiological characterization of raw phosphoric acid, food-grade phosphoric acid, solid waste, and liquid waste was performed by alpha and gamma spectrometry. The (238)U, (234)U, (226)Ra, and (232)Th activity concentrations varied depending on the source of raw phosphoric acid. Decreasing radionuclides activity concentrations in raw phosphoric acids used by the producer of the purified phosphoric acid were observed as follows: Tapira (raw phosphoric acid D) > Catalão (raw phosphoric acids B and C) > Cajati (raw phosphoric acid A). The industrial purification process produces a reduction in radionuclide activity concentrations in food-grade phosphoric acid in relation to raw phosphoric acid produced in plant D and single raw phosphoric acid used in recent years. The most common use of food-grade phosphoric acid is in cola soft drinks, with an average consumption in Brazil of 72 l per person per year. Each liter of cola soft drink contains 0.5 ml of food-grade phosphoric acid, which gives an annual average intake of 36 ml of food-grade phosphoric acid per person. Under these conditions, radionuclide intake through consumption of food-grade phosphoric acid per year per person via cola soft drinks is not hazardous to human health in Brazil

  9. Influence of polymer molecular weight and concentration on coexistence curve of isobutyric acid + water.

    PubMed

    Reddy, P Madhusudhana; Venkatesu, P; Bohidar, H B

    2011-10-27

    We report the influence of variation of molecular weights (MWs = 2, 4, 6, and 9 × 10(5) g mol(-1)) and concentration (C) of a long-chain polymer (polyethylene oxide, PEO) on an upper critical solution temperature (UCST) of isobutyric acid (I) + water (W) using density (ρ) measurements as a function of temperature. The ρ values in each coexisting phase of IW have been measured at three different PEO concentrations (C = 0.395, 0.796, and 1.605 mg/cm(3)) in the near critical composition of IW at temperatures below the system's upper critical point for each molecular weight (MW) of PEO. Further, to ascertain the PEO behavior in IW we have measured the polydispersity values for both coexisting liquid phases by using dynamic light scattering (DLS). The data show that the polymer was significantly affected in the critical region of IW and these various MWs and concentrations of PEO show significant modulation on the critical exponents (β), the critical temperatures (T(c)), and critical composition (ϕ(c)), which are depicting the shape of the coexistence curve. The values of β and T(c) increase with increasing PEO MW and concentrations. Besides, the ϕ(c) values slightly decrease with increasing the C values in the mixture of IW. However, the rate of decrease in ϕ(c) is insignificant. Our experimental results explicitly elucidate that most of polymer chain entangles in water rich phase, thereby the polymer monomers strongly interact with neighbor solvent particles and also intra chain interaction between polymer monomers.

  10. Late dosing with ethacrynic acid can reduce gentamicin concentration in perilymph and protect cochlear hair cells.

    PubMed

    Ding, Dalian; McFadden, Sandra L; Browne, Richard W; Salvi, Richard J

    2003-11-01

    A key factor in the well-known interaction between ethacrynic acid (EA) and aminoglycoside antibiotics (AABs) is disruption of the blood-labyrinth barrier (BLB), leading to rapid entry of EA and AABs into the cochlear fluids. The idea that the blood-labyrinthine fluid concentration gradient might be utilized in a protective manner was tested in the current experiment. We hypothesized that administering EA when gentamicin (GM) levels are higher in the cochlea than in the blood might actually reduce cochlear damage by permitting efflux of GM from the cochlear fluids into the bloodstream, down a concentration gradient and across a temporarily disrupted BLB. Guinea pigs received 1, 11, 14 or 20 injections of GM (125 mg/kg i.m.). Approximately half of the animals also received a single injection of EA (40 mg/kg i.v.) either concurrently or 12-18 h after the last GM injection. Concurrent injection of EA significantly increased GM concentration in serum and perilymph at all time points sampled (2.5, 5-8, and 12 h post injection). Compared to animals that received GM only, animals that received a delayed injection of EA had a significantly lower GM concentration in perilymph, lower thresholds of the compound action potential, and less outer hair cell loss. Collectively, the evidence suggests that EA can reduce GM ototoxicity if it is administered 12-18 h after GM, but the mechanism remains to be elucidated. The results may have implications for the clinical management of aminoglycoside ototoxicity in humans, as well as for understanding the mechanisms underlying AAB/EA interactions.

  11. Tuning Lipase Reaction for Production of Fatty Acids from Oil.

    PubMed

    Odaneth, Annamma A; Vadgama, Rajeshkumar N; Bhat, Anuradha D; Lali, Arvind M

    2016-10-01

    Fats or oils are split partially or completely to obtain fatty acids that find wide applications in oleo-chemical industries. Lipase-mediated complete splitting (hydrolysis) of oils is a green process having great potential to replace the traditional methods of oil splitting. However, cost of lipases, mechanistic kinetic equilibrium and associated operational limitations prove to be deterrents for scale up of the enzymatic oil splitting process. In the present study, we demonstrate the use of immobilised 1,3-regioselective lipase (HyLIP) for complete hydrolysis of oil in monophasic reaction medium. Incorporation of a polar organic solvent (tert-butanol, 1:5, v/v) homogenises the oil-water mixture and contributes positively towards complete hydrolysis. The monophasic oil hydrolysis reaction with optimised water concentration (0.05 %, v/v) gave Free Fatty Acid (FFA) yield of 88 % (HyLIP and Novozym-435) and 66 % (TLIM and RMIM). Smart reaction engineering and modification of the reaction intermediates to favourable substrate lead to ∼99 % degree of hydrolysis of triglycerides with ∼90 % FFA yield using 1,3-regioselective lipase. The present work becomes basic platform for developing technologies for synthesis of fatty acids, monoglycerides, diglycerides and glycerol.

  12. Dietary intake and tissue concentration of fatty acids in omnivore, vegetarian and diabetic pregnancy.

    PubMed

    Lakin, V; Haggarty, P; Abramovich, D R; Ashton, J; Moffat, C F; McNeill, G; Danielian, P J; Grubb, D

    1998-09-01

    The aim of this study was to determine the effect of fatty acid intake and insulin dependent diabetes on the fatty acid composition of maternal erythrocytes, the placenta and cord. Fatty acid intake (from food frequency questionnaire) and the fatty acid composition of maternal erythrocytes, the placenta and cord from pregnant vegetarians (n = 4) and insulin dependent diabetics (n = 5) was compared with pregnant omnivores (n = 10). There was a significantly lower intake of n-6 long chain polyunsaturated fatty acid (LCPUFA) (-75% P < 0.01) and n-3 LCPUFA (-92% P < 0.01) and increased ratio of n-6/n-3 LCPUFA in the vegetarians (103%; P < 0.001). The concentrations of 22:4 n-6 (+28%; P < 0.05) and 22:5 n-3 (+40%; P < 0.05) were higher in vegetarian erythrocytes. Placental 18:2 n-6 (+26.9%; P < 0.05) 18:3 n-3 (+139%; P < 0.05) and 22:5 n-3 (+24%; P < 0.05) were increased while 20:5 n-3 (-36%; P < 0.05), 22:6 n-3 (-16%; P = 0.059), and the ratios of 20:4 n-6/18:2 n-6 (P < 0.01) and 22:6 n-3/18:3 n-3 were reduced. 22:6 n-6 (-49%; P < 0.05) and total n-3 LCPUFA (-11%; P < 0.01) were reduced in vegetarian cord. For the diabetic mothers, all of the n-6 LCPUFA and n-3 LCPUFA were reduced in the maternal erythrocytes; 22:4 n-6 (-42%; P < 0.05), 22:5 n-6 (-46%; P < 0.05) and 22:6 n-3 (-41%; P < 0.05). For the diabetic placenta and cord the general pattern of n-3 LCPUFA was the same as that in the vegetarians. In the vegetarian mothers, the PUFA profiles in the maternal erythrocytes, placenta and cord are consistent with an elevation in the rate of LCPUFA synthesis in order to make up the relative deficit in LCPUFA intake. However, it may be that the higher level of desaturase activity is not able to overcome the dietary deficit of 22-6 n-3 and 22:6 n-6. Despite the fact that the dietary LCPUFA intake in the pregnant diabetic was comparable with that in the pregnant 'normal' omnivore mothers, the pattern of PUFA in the tissues resembled that of the vegetarian mothers.

  13. Upscaling energy concentration in multifrequency single-bubble sonoluminescence with strongly degassed sulfuric acid

    NASA Astrophysics Data System (ADS)

    Dellavale, Damián; Rechiman, Ludmila; Rosselló, Juan Manuel; Bonetto, Fabián

    2012-07-01

    Single-bubble sonoluminescence (SBSL) was explored under a variety of multifrequency excitations. In particular, biharmonic excitation was used to produce SBSL for unprecedented low dissolved noble gas concentrations in a sulfuric acid solution. Reducing the amount of dissolved noble gas makes it possible to reach higher acoustic pressures on the SL bubble, which otherwise are not attainable because of the Bjerknes instability. By using biharmonic excitation, we were able to experimentally trap and to spatially stabilize SL bubbles for xenon pressure overhead as low as 1mbar. As a result, we have access to regions in phase space where the plasma temperatures are higher than the ones reached before for bubbles driven at ≈30kHz.

  14. Gas diffusion electrode setup for catalyst testing in concentrated phosphoric acid at elevated temperatures

    SciTech Connect

    Wiberg, Gustav K. H. E-mail: m.arenz@chem.ku.dk; Fleige, Michael; Arenz, Matthias E-mail: m.arenz@chem.ku.dk

    2015-02-15

    We present a detailed description of the construction and testing of an electrochemical cell setup allowing the investigation of a gas diffusion electrode containing carbon supported high surface area catalysts. The setup is designed for measurements in concentrated phosphoric acid at elevated temperature, i.e., very close to the actual conditions in high temperature proton exchange membrane fuel cells (HT-PEMFCs). The cell consists of a stainless steel flow field and a PEEK plastic cell body comprising the electrochemical cell, which exhibits a three electrode configuration. The cell body and flow field are braced using a KF-25 vacuum flange clamp, which allows an easy assembly of the setup. As demonstrated, the setup can be used to investigate temperature dependent electrochemical processes on high surface area type electrocatalysts, but it also enables quick screening tests of HT-PEMFC catalysts under realistic conditions.

  15. Upscaling energy concentration in multifrequency single-bubble sonoluminescence with strongly degassed sulfuric acid.

    PubMed

    Dellavale, Damián; Rechiman, Ludmila; Rosselló, Juan Manuel; Bonetto, Fabián

    2012-07-01

    Single-bubble sonoluminescence (SBSL) was explored under a variety of multifrequency excitations. In particular, biharmonic excitation was used to produce SBSL for unprecedented low dissolved noble gas concentrations in a sulfuric acid solution. Reducing the amount of dissolved noble gas makes it possible to reach higher acoustic pressures on the SL bubble, which otherwise are not attainable because of the Bjerknes instability. By using biharmonic excitation, we were able to experimentally trap and to spatially stabilize SL bubbles for xenon pressure overhead as low as 1 mbar. As a result, we have access to regions in phase space where the plasma temperatures are higher than the ones reached before for bubbles driven at ≈30 kHz.

  16. Effect of Sulfuric Acid Concentration on Electrochemical Characteristics of Nano Porous Structure Formed by Anodizing Process.

    PubMed

    Lee, Jung-Hyung; Lee, Seung-Jun; Kim, Seong-Jong

    2016-02-01

    Aluminum alloy is a very strong reactivity material, but it has excellent corrosion resistance due to protective oxide film created in air. However, it is not practical because the film thickness is uneven and varies depending on the generation condition. Therefore, aluminum anodizing was performed to form film with commercially applicable hardness, corrosion resistance, and wear resistance. This offers such advantages as commercial applicability to large areas and low prices. In this study, the electrochemical characteristics with concentration of sulfuric acid electrolyte were compared with the two-step anodizing method which is widely used. A surface observation revealed regular structures and pores with the size of several tens of nm, and the anodized film presented excellent corrosion resistance with considerably low corrosion current density in sea water.

  17. Phytanic acid: measurement of plasma concentrations by gas-liquid chromatography-mass spectrometry analysis and associations with diet and other plasma fatty acids.

    PubMed

    Allen, Naomi E; Grace, Philip B; Ginn, Annette; Travis, Ruth C; Roddam, Andrew W; Appleby, Paul N; Key, Timothy

    2008-03-01

    Epidemiological data suggest that a diet rich in animal foods may be associated with an increased risk of several cancers, including cancers of the prostate, colorectum and breast, but the possible mechanism is unclear. It is hypothesised that phytanic acid, a C20 branched-chain fatty acid found predominantly in foods from ruminant animals, may be involved in early cancer development because it has been shown to up regulate activity of alpha-methylacyl-coenzyme A racemase, an enzyme commonly found to be over-expressed in tumour cells compared with normal tissue. However, little is known about the distribution of plasma phytanic acid concentrations or its dietary determinants in the general population. The primary aim of the present cross-sectional study was to determine circulating phytanic acid concentrations among ninety-six meat-eating, lacto-ovo-vegetarian and vegan women, aged 20-69 years, recruited into the Oxford component of the European Prospective Investigation into Cancer and Nutrition (EPIC-Oxford). Meat-eaters had, on average, a 6.7-fold higher geometric mean plasma phytanic acid concentration than the vegans (5.77 v. 0.86 micromol/l; P < 0.0001) and a 47 % higher mean concentration than the vegetarians (5.77 v. 3.93 micromol/l; P = 0.016). The strongest determinant of plasma phytanic acid concentration appeared to be dairy fat intake (r 0.68; P < 0.0001); phytanic acid levels were not associated with age or other lifestyle factors. These data show that a diet high in fat from dairy products is associated with increased plasma phytanic acid concentration, which may play a role in cancer development.

  18. Effects of various antipsychotic drugs upon the striatal concentrations of para-hydroxyphenylacetic acid and meta-hydroxyphenylacetic acid in the mouse.

    PubMed

    Juorio, A V; McQuade, P S

    1983-11-01

    The endogenous concentrations of p- and m-hydroxyphenylacetic acid in the mouse caudate nucleus were determined by a gas chromatographic or a gas chromatographic-mass spectrometric technique and the concentrations were about 30 and 11 ng g-1 respectively. The subcutaneous administration of (+)-butaclamol (1 mg kg-1), haloperidol (5 mg kg-1), molindone (100 mg kg-1), sulpiride (50 mg kg-1) or chlorpromazine (20 mg kg-1) increased the concentration of mouse striatal p- and m-hydroxyphenylacetic acid; the effects were observed at 2 h after drug administration. Lower doses of chlorpromazine (2 mg kg-1), haloperidol (0.2 mg kg-1) and molindone (2 mg kg-1) did not affect p- or m-hydroxyphenylacetic acid concentrations. The time course for the concentration changes produced by chlorpromazine (20 mg kg-1) revealed that the formation of the metabolites occurred within 30 min after its administration and that their efflux from the caudate nucleus took at least 4 h for p-hydroxyphenylacetic acid and more than 8 h for m-hydroxyphenylacetic acid. Promethazine and (-)-butaclamol which have chemical structures related to chlorpromazine or (+)-butaclamol respectively but which lack antipsychotic activity, produced no effect on striatal p- or m-hydroxyphenylacetic acid concentrations. The results suggest that antipsychotic drugs increase the utilization of mouse striatal p- and m-tyramine and that after use the amines are metabolized by monoamine oxidase to form p- or m-hydroxyphenylacetic acid. The synthesis of the acid metabolites occurs within 30 min after chlorpromazine administration and their efflux from the caudate nucleus takes from 4-8 h.

  19. Protein–Protein Interactions in Dilute to Concentrated Solutions: α-Chymotrypsinogen in Acidic Conditions

    PubMed Central

    2015-01-01

    Protein–protein interactions were investigated for α-chymotrypsinogen by static and dynamic light scattering (SLS and DLS, respectively), as well as small-angle neutron scattering (SANS), as a function of protein and salt concentration at acidic conditions. Net protein–protein interactions were probed via the Kirkwood–Buff integral G22 and the static structure factor S(q) from SLS and SANS data. G22 was obtained by regressing the Rayleigh ratio versus protein concentration with a local Taylor series approach, which does not require one to assume the underlying form or nature of intermolecular interactions. In addition, G22 and S(q) were further analyzed by traditional methods involving fits to effective interaction potentials. Although the fitted model parameters were not always physically realistic, the numerical values for G22 and S(q → 0) were in good agreement from SLS and SANS as a function of protein concentration. In the dilute regime, fitted G22 values agreed with those obtained via the osmotic second virial coefficient B22 and showed that electrostatic interactions are the dominant contribution for colloidal interactions in α-chymotrypsinogen solutions. However, as protein concentration increases, the strength of protein–protein interactions decreases, with a more pronounced decrease at low salt concentrations. The results are consistent with an effective “crowding” or excluded volume contribution to G22 due to the long-ranged electrostatic repulsions that are prominent even at the moderate range of protein concentrations used here (<40 g/L). These apparent crowding effects were confirmed and quantified by assessing the hydrodynamic factor H(q → 0), which is obtained by combining measurements of the collective diffusion coefficient from DLS data with measurements of S(q → 0). H(q → 0) was significantly less than that for a corresponding hard-sphere system and showed that hydrodynamic nonidealities can lead to qualitatively incorrect

  20. Determination of plasma lactic acid concentration and specific activity using high-performance liquid chromatography.

    PubMed

    Bleiberg, B; Steinberg, J J; Katz, S D; Wexler, J; LeJemtel, T

    1991-08-23

    Assessment of lactate metabolism is of particular interest during exercise and in disease states such as diabetes, shock, and absorptive abnormalities of short-chain fatty acids by the colon. We describe an analytical method that introduces radio-active tracers and high-performance liquid chromatography (HPLC) to simultaneously analyze concentrations and specific activities (SAs) of plasma lactate. The HPLC conditions included separation on a reversed-phase column (octadecylsilane) and an isocratic buffer (30% acetonitrile in water). [3H]Acetate served as an internal standard. Lactate and acetate were extracted from plasma samples with diethyl ether following a pH adjustment to less than 1.0 and back-extracted into a hydrophilic phase with sodium carbonate (2 mM, pH greater than 10.0). Lactate is detected in the ultraviolet range (242 and 320 nm) by derivatization with alpha-bromoacetophenone. Control plasma samples were studied after an overnight fast for precision and analytical recovery. Calibration curves were linear in the range 0.18-6.0 mM (r = 0.92). The precision was 3% and the analytical recovery was 87%. The detection limit of the method was 36 pmol. Determination of lactate metabolism was performed in a patient with chronic congestive heart failure who was administered primed-continuous L-[U-14C]lactate (10 microCi bolus and 0.3 microCi/min continuously) during a 60-min rest period. Mean arterial lactate concentration and SA were 1.69 +/- 0.2 mM and 253.8 +/- 22 dpm/mumol, respectively. Systemic lactate turnover was 25.65 mumol/kg per min. Lactic acid systemic turnover, organ uptake and release rates can be accurately determined by isocratic HPLC.

  1. Treatment of Type 2 Diabetes by Free Fatty Acid Receptor Agonists

    PubMed Central

    Watterson, Kenneth R.; Hudson, Brian D.; Ulven, Trond; Milligan, Graeme

    2014-01-01

    Dietary free fatty acids (FFAs), such as ω-3 fatty acids, regulate metabolic and anti-inflammatory processes, with many of these effects attributed to FFAs interacting with a family of G protein-coupled receptors. Selective synthetic ligands for free fatty acid receptors (FFA1-4) have consequently been developed as potential treatments for type 2 diabetes (T2D). In particular, clinical studies show that Fasiglifam, an agonist of the long-chain FFA receptor, FFA1, improved glycemic control and reduced HbA1c levels in T2D patients, with a reduced risk of hypoglycemia. However, this ligand was removed from clinical trials due to potential liver toxicity and determining if this is a target or a ligand-specific feature is now of major importance. Pre-clinical studies also show that FFA4 agonism increases insulin sensitivity, induces weight loss, and reduces inflammation and the metabolic and anti-inflammatory effects of short chain fatty acids (SCFAs) are linked with FFA2 and FFA3 activation. In this review, we therefore show that FFA receptor agonism is a potential clinical target for T2D treatment and discuss ongoing drug development programs within industry and academia aimed at improving the safety and effectiveness of these potential treatments. PMID:25221541

  2. Influence of ethylenediamine-n,n’-disuccinic acid (EDDS) concentration on the bactericidal activity of fatty acids in vitro

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The antibacterial activity of mixtures of ethylenediamine-N,N’-disuccinic acid (EDDS) and antibacterial fatty acids (FA) was examined using the agar diffusion assay. Solutions of caproic, caprylic, capric, and lauric acids dissolved in potassium hydroxide (KOH) were supplemented with 0, 5, or 10 mM ...

  3. A simple procedure for preparing chitin oligomers through acetone precipitation after hydrolysis in concentrated hydrochloric acid.

    PubMed

    Kazami, Nao; Sakaguchi, Masayoshi; Mizutani, Daisuke; Masuda, Tatsuhiko; Wakita, Satoshi; Oyama, Fumitaka; Kawakita, Masao; Sugahara, Yasusato

    2015-11-05

    Chitin oligomers are of interest because of their numerous biologically relevant properties. To prepare chitin oligomers containing 4-6 GlcNAc units [(GlcNAc)4-6], α- and β-chitin were hydrolyzed with concentrated hydrochloric acid at 40 °C. The reactant was mixed with acetone to recover the acetone-insoluble material, and (GlcNAc)4-6 was efficiently recovered after subsequent water extraction. Composition analysis using gel permeation chromatography and MALDI-TOF mass spectrometry indicated that (GlcNAc)4-6 could be isolated from the acetone-insoluble material with recoveries of approximately 17% and 21% from the starting α-chitin and β-chitin, respectively. The acetone precipitation method is highly useful for recovering chitin oligomers from the acid hydrolysate of chitin. The changes in the molecular size and higher-order structure of chitin during the course of hydrolysis were also analyzed, and a model that explains the process of oligomer accumulation is proposed.

  4. Effect of L (+) ascorbic acid and monosodium glutamate concentration on the morphology of calcium carbonate

    NASA Astrophysics Data System (ADS)

    Saraya, Mohamed El-shahte Ismaiel

    2015-11-01

    In this study, monosodium glutamate and ascorbic acid were used as crystal and growth modifiers to control the crystallization of CaCO3. Calcium carbonate prepared by reacting a mixed solution of Na2CO3 with CaCl2 at ambient temperature, (25 °C), constant Ca++/ CO3- - molar ratio and pH with stirring. The polymorph and morphology of the crystals were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM) and differential scanning calorimetry (DSC). The results indicate that rhombohedral calcite was only formed in water without organic additives, and both calcite and spherical vaterite with various morphologies were produced in the presence of monosodium glutamate. The content of vaterite increased as the monosodium glutamate increased. In addition, spherical vaterite was obtained in the presence of different concentrations of ascorbic acid. The spherical vaterite posses an aggregate shape composed of nano-particles, ranging from 30 to 50 nm as demonstrated by the SEM and TEM analyses. Therefore, the ascorbic stabilizes vaterite and result in nano-particles compared to monosodium glutamate.

  5. The type and concentration of milk increase the in vitro bioaccessibility of coffee chlorogenic acids.

    PubMed

    Tagliazucchi, Davide; Helal, Ahmed; Verzelloni, Elena; Conte, Angela

    2012-11-07

    Coffee with different types and concentrations of milk was digested with pepsin (2 h) and pancreatin (2 h) to simulate gastropancreatic digestion. Chlorogenic acids (CGAs) were determined by high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry in ultrafiltrate (cutoff 3 kDa) to evaluate their bioaccessibility. After digestion, bioaccessible CGAs decreased from 80.2 to 53.0 and 69.5 μmol/200 mL in coffee without milk and coffee-whole milk, respectively. When whole, semiskimmed, skimmed, or diluted milk were present, the increase in bioaccessibility was dependent on fat content (r = 0.99, p < 0.001). No relationship was observed between bioaccessibility and proteins, carbohydrates, and calcium content. The addition of milk to coffee caused an immediate decrease in the bioaccessibility due to CGAs binding to proteins. After digestion, 86-94% of bound CGAs remained in the high molecular weight fraction. Casein bound 5-caffeoylquinic acid with high affinity (K(D) of 37.9 ± 2.3 μmol/L; n = 0.88 ± 0.06).

  6. Highly improved synthesis of gold nanobipyramids by tuning the concentration of hydrochloric acid

    NASA Astrophysics Data System (ADS)

    Qi, Ying; Zhu, Jian; Li, Jianjun; Zhao, Junwu

    2016-07-01

    Fabrication of gold nanobipyramids (Au BPs) has attracted great attention because they exhibit more advantageous plasmonic properties. In this study, Au BPs were synthesized by the well-known seeded growth in the presence of hydrochloric acid (HCl). The effects of the ingredients, including HCl, silver nitrate (AgNO3), l-Ascorbic acid (AA), and seeds on the structure and yield of the Au BPs were systemically investigated. The results showed that the abundant HCl could improve the yield of Au BPs and decrease the longitudinal surface plasmon resonance wavelength. Under the circumstance of higher concentration of AA and AgNO3, more byproducts were resulted. In addition, the effect of HCl under different ratios of seed solution to AA has also been studied. The results showed that the yield was less sensitive to HCl when the amount of seed solution was small. If substantial AA was added to the system, then abundant HCl should be introduced correspondingly to improve the yield of Au BPs.

  7. How do background ozone concentrations affect the biosynthesis of rosmarinic acid in Melissa officinalis?

    PubMed

    Döring, Anne S; Pellegrini, Elisa; Della Batola, Michele; Nali, Cristina; Lorenzini, Giacomo; Petersen, Maike

    2014-03-01

    Lemon balm (Melissa officinalis; Lamiaceae) plants were exposed to background ozone (O3) dosages (80ppb for 5h), because high background levels of O3 are considered to be as harmful as episodic O3 peaks. Immediately at the end of fumigation the plants appeared visually symptomless, but necrotic lesions were observed later. The biosynthesis of rosmarinic acid (RA) comprises eight enzymes, among them phenylalanine ammonia-lyase (PAL), 4-coumarate:coenzyme A ligase (4CL), tyrosine aminotransferase (TAT) and rosmarinic acid synthase (RAS). The transcript levels of these genes have been investigated by quantitative RT-PCR. There was a quick up-regulation of all genes at 3h of O3 exposure, but at 24h from beginning of exposure (FBE) only RAS and PAL were up-regulated. The specific activity of RAS was closely correlated with a decrease of RA concentration in lemon balm leaves. The specific activity of PAL increased at 12h FBE to 163% in comparison to control levels. This work provides insight into the effect of O3 stress on the formation of the main phenolic ingredient of the pharmaceutically important plant M. officinalis.

  8. Estimate of serum immunoglobulin G concentration using refractometry with or without caprylic acid fractionation.

    PubMed

    Morrill, K M; Polo, J; Lago, A; Campbell, J; Quigley, J; Tyler, H

    2013-07-01

    Objectives of this study were to develop a rapid calf-side test to determine serum IgG concentrations using caprylic acid (CA) fractionation, followed by refractometry of the IgG-rich supernatant and compare the accuracy of this method with results obtained using refractometry using raw serum. Serum samples (n=200) were obtained from 1-d-old calves, frozen (-20°C), and shipped to the laboratory. Samples were allowed to thaw for 1h at room temperature. Fractionation with CA was conducted by adding 1mL of serum to a tube containing 45, 60, or 75µL of CA and 0.5, 1.0, or 1.5mL of 0.06 M acetic acid. The tube contents were mixed well, allowed to react for 1 min, and then centrifuged at 3,300 × g for 0, 10, or 20 min at 25°C. The %Brix and refractive index of the fractionated supernatant were determined using a digital refractometer. Nonfractionated serum was analyzed for %Brix (BRn), refractive index (nDn), and IgG concentration by radial immunodiffusion. The mean serum IgG concentration was 19.0 mg/mL [standard deviation (SD)=9.7], with a range of 3.5 to 47.0 mg/mL. The mean serum BRn was 8.6 (SD=0.91), with a range of 6.8 to 11.0. The mean serum nDn was 1.34566 (SD=0.00140), with a range of 1.34300 to 1.34930. Serum nDn was positively correlated with IgG concentration (correlation coefficient=0.86; n=185). Fractionated samples treated with 1mL 0.6 M acetic acid and 60µL of CA and not centrifuged before analysis resulted in a strong relationship between the refractive index of the fractionated supernatant and IgG (correlation coefficient=0.80; n=45). Regression was used to determine cut points indicative of 10, 12, and 14 mg of IgG/mL to determine the sensitivity and specificity of refractometry to identify failure of passive transfer (serum IgG <10 mg/mL at 24 h old). The nDn were 1.34414, 1.34448, and 1.34480 to predict 10, 12, and 14 mg of IgG/mL of serum, respectively. The BRn cut points were 7.6, 7.8, and 8.0, respectively. The nDn cut points of 1.34448 and

  9. Digestibility by lambs offered alfalfa hay treated with a propionic acid hay preservative and baled at different concentrations of moisture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Eighteen crossbred wether lambs (76.1 ± 8.18 lb initial BW) were used for a 2 period digestion study to evaluate the effect of hay preservative concentration (0, 0.56, or 0.98% buffered propionic acid) and hay moisture concentration at baling (19.6, 23.8, or 27.4% moisture) on digestibility of alfal...

  10. Selection of suitable mineral acid and its concentration for biphasic dilute acid hydrolysis of the sodium dithionite delignified Prosopis juliflora to hydrolyze maximum holocellulose.

    PubMed

    Naseeruddin, Shaik; Desai, Suseelendra; Venkateswar Rao, L

    2016-02-01

    Two grams of delignified substrate at 10% (w/v) level was subjected to biphasic dilute acid hydrolysis using phosphoric acid, hydrochloric acid and sulfuric acid separately at 110 °C for 10 min in phase-I and 121 °C for 15 min in phase-II. Combinations of acid concentrations in two phases were varied for maximum holocellulose hydrolysis with release of fewer inhibitors, to select the suitable acid and its concentration. Among three acids, sulfuric acid in combination of 1 & 2% (v/v) hydrolyzed maximum holocellulose of 25.44±0.44% releasing 0.51±0.02 g/L of phenolics and 0.12±0.002 g/L of furans, respectively. Further, hydrolysis of delignified substrate using selected acid by varying reaction time and temperature hydrolyzed 55.58±1.78% of holocellulose releasing 2.11±0.07 g/L and 1.37±0.03 g/L of phenolics and furans, respectively at conditions of 110 °C for 45 min in phase-I & 121 °C for 60 min in phase-II.

  11. Uric acid concentration in subjects at risk of type 2 diabetes mellitus: relationship to components of the metabolic syndrome.

    PubMed

    Costa, A; Igualá, I; Bedini, J; Quintó, L; Conget, I

    2002-03-01

    High uric acid concentration is a common finding in subjects with risk factors for cardiovascular disease (CVD), including some characteristics of the metabolic syndrome. However, its exact role in this setting and in the progression to type 2 diabetes mellitus (DM) is not well understood and could be affected by confounding factors such as hypertriglyceridemia. Our study aimed to establish the relationship between uric acid (avoiding the interference of high triglyceride levels), insulin sensitivity, and components of the metabolic syndrome in a group of subjects at high risk of developing DM. Among 201 subjects included in the study, 111 (55.2%) showed an abnormal oral glucose tolerance and uric acid levels higher than those measured in subjects with normal glucose tolerance. Body mass index (BMI), triglycerides, diastolic blood pressure (DBP), and 2-hour glycemia in the oral glucose tolerance test (OGTT) contributed independently to uric acid concentration (R2 =.59). However, uric acid did not affect either insulin sensitivity or glucose tolerance. The recovery tests revealed that a triglyceride concentration > or = 3 mmol/L interfered with the measurement of uric acid level when a colorimetric method was used, but not when a dry-chemistry method was used. In conclusion, uric acid concentration is higher in subjects at high risk of DM with abnormal glucose tolerance and is independently determined by various components of the metabolic syndrome.

  12. Low Dose Gamma Irradiation Does Not Affect the Quality or Total Ascorbic Acid Concentration of "Sweetheart" Passionfruit (Passiflora edulis).

    PubMed

    Golding, John B; Blades, Barbara L; Satyan, Shashirekha; Spohr, Lorraine J; Harris, Anne; Jessup, Andrew J; Archer, John R; Davies, Justin B; Banos, Connie

    2015-08-26

    Passionfruit (Passiflora edulis, Sims, cultivar "Sweetheart") were subject to gamma irradiation at levels suitable for phytosanitary purposes (0, 150, 400 and 1000 Gy) then stored at 8 °C and assessed for fruit quality and total ascorbic acid concentration after one and fourteen days. Irradiation at any dose (≤1000 Gy) did not affect passionfruit quality (overall fruit quality, colour, firmness, fruit shrivel, stem condition, weight loss, total soluble solids level (TSS), titratable acidity (TA) level, TSS/TA ratio, juice pH and rot development), nor the total ascorbic acid concentration. The length of time in storage affected some fruit quality parameters and total ascorbic acid concentration, with longer storage periods resulting in lower quality fruit and lower total ascorbic acid concentration, irrespective of irradiation. There was no interaction between irradiation treatment and storage time, indicating that irradiation did not influence the effect of storage on passionfruit quality. The results showed that the application of 150, 400 and 1000 Gy gamma irradiation to "Sweetheart" purple passionfruit did not produce any deleterious effects on fruit quality or total ascorbic acid concentration during cold storage, thus supporting the use of low dose irradiation as a phytosanitary treatment against quarantine pests in purple passionfruit.

  13. Seasonal variations in the concentrations of lipophilic compounds and phenolic acids in the roots of Echinacea purpurea and Echinacea pallida.

    PubMed

    Thomsen, Maria O; Fretté, Xavier C; Christensen, Kathrine B; Christensen, Lars P; Grevsen, Kai

    2012-12-12

    Roots of Echinacea purpurea and Echinacea pallida cultivated for 4 years in a North European climate were analyzed for seasonal variations in the concentrations of lipophilic constituents (alkamides, ketoalkenes, and ketoalkynes) and phenolic acids by harvesting five times during 1 year to establish the optimal time for harvest. A total of 16 alkamides, three ketoalkenes, two ketoalkynes, and four phenolic acids (echinacoside, cichoric acid, caftaric acid, and chlorogenic acid) were identified in aqueous ethanolic (70%) extracts by liquid chromatography-mass spectrometry and quantified by reverse-phase high-performance liquid chromatography. The major alkamides in the roots of E. purpurea were at their lowest concentration in the middle of autumn and early winter, and the total concentration of lipophilic compounds in E. pallida showed the same pattern. Moreover, all of the major phenolic acids in E. purpurea were at their highest concentrations in spring. The optimal harvest time in spring is in contrast to normal growing guidelines; hence, this specific information of seasonal variations in the concentrations of lipophilic and phenolic compounds in E. purpurea and E. pallida is valuable for research, farmers, and producers of medicinal preparations.

  14. Flufenamic acid prevents behavioral manifestations of salicylate-induced tinnitus in the rat

    PubMed Central

    Ustundag, Yasemin; Bulut, Funda; Demir, Caner Feyzi; Bal, Ali

    2016-01-01

    Introduction Tinnitus is defined as a phantom auditory sensation, the perception of sound in the absence of external acoustic stimulation. Given that flufenamic acid (FFA) blocks TRPM2 cation channels, resulting in reduced neuronal excitability, we aimed to investigate whether FFA suppresses the behavioral manifestation of sodium salicylate (SSA)-induced tinnitus in rats. Material and methods Tinnitus was evaluated using a conditioned lick suppression model of behavioral testing. Thirty-one Wistar rats, randomly divided into four treatment groups, were trained and tested in the behavioral experiment: (1) control group: DMSO + saline (n = 6), (2) SSA group: DMSO + SSA (n = 6), (3) FFA group: FFA (66 mg/kg bw) + saline (n = 9), (4) FFA + SSA group: FFA (66 mg/kg bw) + SSA (400 mg/kg bw) (n = 10). Localization of TRPM2 to the plasma membrane of cochlear nucleus neurons was demonstrated by confocal microscopy. Results Pavlovian training resulted in strong suppression of licking, having a mean value of 0.05 ±0.03 on extinction day 1, which is below the suppression training criterion level of 0.20 in control tinnitus animals. The suppression rate for rats having both FFA (66 mg/kg bw) and SSA (400 mg/kg bw) injections was significantly lower than that for the rats having SSA injections (p < 0.01). Conclusions We suggest that SSA-induced tinnitus could possibly be prevented by administration of a TRPM2 ion channel antagonist, FFA at 66 mg/kg bw. PMID:26925138

  15. Removal of low concentrations of ammonium and humic acid from simulated groundwater by Vermiculite/Palygorskite mixture.

    PubMed

    Zhang, Xiuli; Lv, Guocheng; Liao, Libing; He, Maoqian; Li, Zhaohui; Wang, Mingshan

    2012-08-01

    Contaminants in water are classified into different types based on their physical and chemical properties. Thus, more than one type of sorbents may be needed for their removal. In this article, a combination of vermiculite with palygorskite was studied for their simultaneous removal of ammonium and humic acid from simulated groundwater. Batch results showed that the Langmuir model described ammonium adsorption well with an adsorption capacity of 22 mg/g while the humic acid adsorption data fitted to the linear adsorption better, suggesting different removal mechanisms of these two types of contaminants. Kinetic studies showed an instantaneous removal of ammonium and humic acid. A column packed with mixture of equal volumes of vermiculite and palygorskite could treat 100 pore volumes for ammonium removal at an initial concentration of 10 mg/L and 500 pore volumes for humic acid removal at an initial concentration of 20 mg/L before the effluent concentrations exceeded the standard.

  16. THE EFFECT OF ANOLYTE PRODUCT ACID CONCENTRATION ON HYBRID SULFUR CYCLE PERFORMANCE

    SciTech Connect

    Gorensek, M.; Summers, W.

    2010-03-24

    The Hybrid Sulfur (HyS) cycle (Fig. 1) is one of the simplest, all-fluids thermochemical cycles that has been devised for splitting water with a high-temperature nuclear or solar heat source. It was originally patented by Brecher and Wu in 1975 and extensively developed by Westinghouse in the late 1970s and early 1980s. As its name suggests, the only element used besides hydrogen and oxygen is sulfur, which is cycled between the +4 and +6 oxidation states. HyS comprises two steps. One is the thermochemical (>800 C) decomposition of sulfuric acid (H{sub 2}SO{sub 4}) to sulfur dioxide (SO{sub 2}), oxygen (O{sub 2}), and water. H{sub 2}SO{sub 4} = SO{sub 2} + 1/2 O{sub 2} + H{sub 2}O. The other is the SO{sub 2}-depolarized electrolysis of water to H{sub 2}SO{sub 4} and hydrogen (H{sub 2}), SO{sub 2} + 2 H{sub 2}O = H{sub 2}SO{sub 4} + H{sub 2}, E{sup o} = -0.156 V, explaining the 'hybrid' designation. These two steps taken together split water into H{sub 2} and O{sub 2} using heat and electricity. Researchers at the Savannah River National Laboratory (SRNL) and at the University of South Carolina (USC) have successfully demonstrated the use of proton exchange membrane (PEM) electrolyzers (Fig. 2) for the SO{sub 2}-depolarized electrolysis (sulfur oxidation) step, while Sandia National Laboratories (SNL) successfully demonstrated the high-temperature sulfuric acid decomposition (sulfur reduction) step using a bayonet-type reactor (Fig. 3). This latter work was performed as part of the Sulfur-Iodine (SI) cycle Integrated Laboratory Scale demonstration at General Atomics (GA). The combination of these two operations results in a simple process that will be more efficient and cost-effective for the massive production of hydrogen than alkaline electrolysis. Recent developments suggest that the use of PEMs other than Nafion will allow sulfuric acid to be produced at higher concentrations (>60 wt%), offering the possibility of net thermal efficiencies around 50% (HHV basis

  17. Production rates of bacterial tetraether lipids and fatty acids in peatland under varying oxygen concentrations

    NASA Astrophysics Data System (ADS)

    Huguet, Arnaud; Meador, Travis B.; Laggoun-Défarge, Fatima; Könneke, Martin; Wu, Weichao; Derenne, Sylvie; Hinrichs, Kai-Uwe

    2017-04-01

    Interpretations of the abundance and distribution of branched glycerol dialkyl glycerol tetraether (brGDGT) lipids have been increasingly applied to infer changes in paleoenvironment and to estimate terrigenous organic matter inputs into estuarine and marine sediments. However, only preliminary information is known regarding the ecology and physiology of the source organisms of these biomarkers. We assessed the production rates of brGDGTs under different redox conditions in peat, where these lipids are found in high concentrations, particularly at greater depths below the fluctuating water table. The incorporation of hydrogen relative to carbon into lipids observed in our dual stable isotope probing assay indicates that brGDGTs were produced by heterotrophic bacteria. Unexpectedly, incubations with stable isotope tracers of the surface horizon (5-20 cm) initiated under oxic conditions before turning suboxic and eventually anoxic exhibited up to one order of magnitude higher rates of brGDGT production (16-87 ng cm-3 y-1) relative to the deeper, anoxic zone (20-35 cm; ca. 7 ng cm-3 y-1), and anoxic incubations of the surface horizon (<3 ng cm-3 y-1). Turnover times of brGDGTs in the surface horizon ranged between 8 and 41 years in the incubations initiated under oxic conditions, in contrast to 123-742 years in anoxic incubations. As brGDGTs were actively produced during both anoxic incubations and those exposed to oxygen, we conclude that their source organisms are likely facultative aerobic heterotrophs that are particularly active in the peat acrotelm. Production rates of bacterial fatty acids (ca. 2 μg cm-3 y-1) were roughly two orders of magnitude higher than those of brGDGTs, suggesting that brGDGT producers are a minor constituent of the microbial community or that brGDGTs are a small component of the microbial cell membrane in comparison to fatty acids, despite the typically high brGDGT concentrations observed in peat. Multivariate analysis identified two

  18. Importance of ALDH1A enzymes in determining human testicular retinoic acid concentrations

    PubMed Central

    Arnold, Samuel L.; Kent, Travis; Hogarth, Cathryn A.; Schlatt, Stefan; Prasad, Bhagwat; Haenisch, Michael; Walsh, Thomas; Muller, Charles H.; Griswold, Michael D.; Amory, John K.; Isoherranen, Nina

    2015-01-01

    Retinoic acid (RA), the active metabolite of vitamin A, is required for spermatogenesis and many other biological processes. RA formation requires irreversible oxidation of retinal to RA by aldehyde dehydrogenase enzymes of the 1A family (ALDH1A). While ALDH1A1, ALDH1A2, and ALDH1A3 all form RA, the expression pattern and relative contribution of these enzymes to RA formation in the testis is unknown. In this study, novel methods to measure ALDH1A protein levels and intrinsic RA formation were used to accurately predict RA formation velocities in individual human testis samples and an association between RA formation and intratesticular RA concentrations was observed. The distinct localization of ALDH1A in the testis suggests a specific role for each enzyme in controlling RA formation. ALDH1A1 was found in Sertoli cells, while only ALDH1A2 was found in spermatogonia, spermatids, and spermatocytes. In the absence of cellular retinol binding protein (CRBP)1, ALDH1A1 was predicted to be the main contributor to intratesticular RA formation, but when CRBP1 was present, ALDH1A2 was predicted to be equally important in RA formation as ALDH1A1. This study provides a comprehensive novel methodology to evaluate RA homeostasis in human tissues and provides insight to how the individual ALDH1A enzymes mediate RA concentrations in specific cell types. PMID:25502770

  19. Aquatic predicted no-effect-concentration derivation for perfluorooctane sulfonic acid.

    PubMed

    Qi, Ping; Wang, Ying; Mu, Jingli; Wang, Juying

    2011-04-01

    Perfluorooctane sulfonic acid (PFOS), a representative perfluorinated surfactant, is an anthropogenic pollutant detected in various environmental and biological matrices. Some laboratory and field work has been conducted to assess the aquatic toxicity of PFOS, but little is known regarding its toxicity threshold to the aquatic ecosystem. In the present study, predicted no-effect concentrations (PNECs) were derived by four different approaches. The interspecies correlation estimation (ICE) program and final acute-to-chronic ratio (FACR) were applied to the development of PNEC based on the toxic mode of action (MOA) of PFOS. By comparison of the different PNECs, the recommended aquatic toxicity thresholds for PFOS are in the range of 0.61 to 6.66 µg/L. Based on comparison of PNEC values, microcosm results, and reported environmental concentrations, PFOS appears not to pose a serious threat to aquatic organisms. The present results demonstrate that MOA is an important consideration for the derivation of reliable PNECs; moreover, the ICE-based species sensitivity distribution (SSD) method can be used to derive PNECs when toxicological data are limited. The application of MOA and ICE for deriving PNEC values in the present study may facilitate studies on using a combination of quantitative structure-activity relationship (QSAR) models and ICE to estimate PNECs.

  20. Changes in satiety hormone concentrations and feed intake in rats in response to lactic acid bacteria.

    PubMed

    Forssten, Sofia D; Korczyńska, Marta Z; Zwijsen, Renate M L; Noordman, Wouter H; Madetoja, Mari; Ouwehand, Arthur C

    2013-12-01

    A negative energy balance can be accomplished by reducing the caloric intake which results in an increased feeling of hunger. This physiological state is regulated by secretion of satiety hormones. The secretion of these hormones can be influenced by ingestion of e.g. fat. Fat, dairy beverage and synbiotic mixture have been found to have satiety-inducing effects in humans and rats. Thus, the aim of this study was to investigate the change of satiety hormone concentration in rats in response to feeding of fermented milks containing lactic acid bacteria. Two studies were conducted with Wistar rats randomly allocated into groups receiving Lactobacillus fermented (2 L. acidophilus, L. bulgaricus, L. salivarius and L. rhamnosus) milk. A single isocaloric oral dose with the test item or control was given to the rats. Blood samples were taken after dosing with the test product and the satiety hormones were measured. For the test groups, significant changes could be detected in PYY concentrations after 60 min, although some groups had a significant lower feed intake. In conclusion, some probiotic Lactobacillus strains may modify satiety hormones production. However, more studies are needed to evaluate their potential of prolonging satiety.

  1. Potentiation of vasoconstriction and pressor response by low concentration of monomethylarsonous acid (MMA(III)).

    PubMed

    Lim, Kyung-Min; Shin, Yoo-Sun; Kang, Seojin; Noh, Ji-Yoon; Kim, Keunyoung; Chung, Seung-Min; Yun, Yeo-Pyo; Chung, Jin-Ho

    2011-09-10

    A close link between arsenic exposure and hypertension has been well-established through many epidemiological reports, yet the mechanism underlying it remains unclear. Here we report that nanomolar concentrations of monomethylarsonous acid (MMA(III)), a toxic trivalent methylated arsenic metabolite, can potentiate agonist-induced vasoconstriction and pressor responses. In freshly isolated rat aortic ring, exposure to nanomolar MMA(III) (100-500 nM) potentiated phenylephrine (PE)-induced vasoconstriction while at higher concentrations (≥2.5 μM), suppression of vasoconstriction and apoptosis of vascular smooth muscle were observed. Potentiation of agonist-induced vasoconstriction was also observed with other contractile agonists and it was retained in endothelium-denuded aortic rings, suggesting that these events are agonist-independent and smooth muscle cell dependent. Interestingly, exposure to MMA(III) resulted in increased myosin light chain phosphorylation while PE-induced Ca2+ influx was not affected, reflecting that Ca2+ sensitization is involved. In line with this, MMA(III) enhanced agonist-induced activation of small GTPase RhoA, a key contributor to Ca2+ sensitization. Of note, treatment of MMA(III) to rats induced significantly higher pressor responses in vivo, demonstrating that this event can occur in vivo indeed. We believe that RhoA-mediated Ca2+ sensitization and the resultant potentiation of vasoconstriction by MMA(III) may shed light on arsenic-associated hypertension.

  2. Solubility Challenges in High Concentration Monoclonal Antibody Formulations: Relationship with Amino Acid Sequence and Intermolecular Interactions.

    PubMed

    Pindrus, Mariya; Shire, Steven J; Kelley, Robert F; Demeule, Barthélemy; Wong, Rita; Xu, Yiren; Yadav, Sandeep

    2015-11-02

    The purpose of this work was to elucidate the molecular interactions leading to monoclonal antibody self-association and precipitation and utilize biophysical measurements to predict solubility behavior at high protein concentration. Two monoclonal antibodies (mAb-G and mAb-R) binding to overlapping epitopes were investigated. Precipitation of mAb-G solutions was most prominent at high ionic strength conditions and demonstrated strong dependence on ionic strength, as well as slight dependence on solution pH. At similar conditions no precipitation was observed for mAb-R solutions. Intermolecular interactions (interaction parameter, kD) related well with high concentration solubility behavior of both antibodies. Upon increasing buffer ionic strength, interactions of mAb-R tended to weaken, while those of mAb-G became more attractive. To investigate the role of amino acid sequence on precipitation behavior, mutants were designed by substituting the CDR of mAb-R into the mAb-G framework (GM-1) or deleting two hydrophobic residues in the CDR of mAb-G (GM-2). No precipitation was observed at high ionic strength for either mutant. The molecular interactions of mutants were similar in magnitude to those of mAb-R. The results suggest that presence of hydrophobic groups in the CDR of mAb-G may be responsible for compromising its solubility at high ionic strength conditions since deleting these residues mitigated the solubility issue.

  3. Influence of phytic acid concentration on coating properties obtained by MAO treatment on magnesium alloys

    NASA Astrophysics Data System (ADS)

    Zhang, R. F.; Zhang, S. F.; Duo, S. W.

    2009-06-01

    Anodic coatings were prepared by microarc oxidation (MAO) on AZ91HP in a base solution of 10 g/L NaOH with and without the addition of 0-12 g/L phytic acid (C 6H 18O 24P 6). The influences of C 6H 18O 24P 6 and its concentration on the conductivity and breakdown voltage were studied. The morphologies and compositions of anodic coatings were determined by environmental scanning electron microscope (ESEM) and energy dispersive X-ray spectroscopy (EDX). Potentiodynamic polarization test was performed in 3.5 wt.% NaCl solution to evaluate the corrosion resistance of anodic coatings. The results showed that with the increase of C 6H 18O 24P 6 concentration, the solution conductivity decreased while the values of breakdown voltage increased. EDX analysis showed that the coatings formed in solutions with C 6H 18O 24P 6 addition contained Mg, Al, O, C, P and a trance of Na. The addition of C 6H 18O 24P 6 into the base solution was helpful in coating formation and the coatings formed in the solution containing 8 g/L C 6H 18O 24P 6 exhibited the best pore uniformity and corrosion resistance.

  4. Estimate of colostral immunoglobulin G concentration using refractometry without or with caprylic acid fractionation.

    PubMed

    Morrill, K M; Conrad, E; Polo, J; Lago, A; Campbell, J; Quigley, J; Tyler, H

    2012-07-01

    Our objectives were to evaluate the use of refractometry as a means of estimating immunoglobulin G (IgG) concentration of bovine maternal colostrum (MC) and determine if fractionation of MC using caprylic acid (CA) improved estimates of IgG. Samples (n=85) of MC were collected from a single dairy in California and used to determine the method of CA fraction that produced the best prediction of IgG based on CA fractionation followed by refractometry. Subsequently, samples of MC (n=827) were collected from 67 farms in 12 states to compare refractometry with or without CA fractionation as methods to estimate IgG concentration. Samples were collected from the feeding pool and consisted of fresh (n=196), previously frozen (n=479), or refrigerated (n=152) MC. Samples were further classified by the number freeze-thaw cycles before analysis. Fractionation with CA was conducted by adding 1 mL of MC to a tube containing 75 μL of CA and 1 mL of 0.06 M acetic acid. The tube was shaken and allowed to react for 1 min. Refractive index of the IgG-rich supernatant (nDf) was determined using a digital refractometer. Whole, nonfractionated MC was analyzed for IgG by radial immunodiffusion (RID) and refractive index (nDw). The relationship between nDf and IgG (r=0.53; n=805) was weak, whereas that between nDw and IgG was stronger (r=0.73; n=823). Fresh samples analyzed by refractometry that subsequently went through 1 freeze-thaw cycle before RID analysis resulted in the strongest relationship between IgG and nDf or nDw (r=0.93 and 0.90, respectively). The MC samples collected fresh on the farm but frozen 2 or more times before analysis by refractometry or RID had low correlations between IgG and nDf and nDw (r=0.09 and 0.01). Samples refrigerated or frozen on the farm before analysis had weaker relationships between RID and nDf or nDw (r=0.38 to 0.80), regardless of the number of freeze-thaw cycles. Breed and lactation number did not affect the accuracy of either test. These

  5. Pretreatment by low-dose fibrates protects against acute free fatty acid-induced renal tubule toxicity by counteracting PPAR{alpha} deterioration

    SciTech Connect

    Takahashi, Kyoko; Kamijo, Yuji; Hora, Kazuhiko; Hashimoto, Koji; Higuchi, Makoto; Nakajima, Takero; Ehara, Takashi; Shigematsu, Hidekazu; Gonzalez, Frank J.; Aoyama, Toshifumi

    2011-05-01

    {alpha} activator that has a steady serum concentration regardless of kidney dysfunction. - Graphical Abstract: Massive proteinuria introduces free fatty acid toxicity to proximal tubular epithelial cells (PTECs). PPAR{alpha} activationvia clofibrate pretreatment maintains fatty acid catabolism and attenuates oxidative stress, apoptosis, and NF{kappa}B activation, resulting in protection of PTECs. The favorable properties of fibrates are evident when PPAR{alpha}-dependent tubular protective effects outweigh their PPAR{alpha}-independent tubular toxicities. Display Omitted Highlights: > Clofibrate pretreatment protects against acute FFA-induced tubular toxicity. > PPAR{alpha} activation decreases FFA influx and maintains fatty acid catabolism. > PPAR{alpha} activation attenuates oxidative stress, apoptosis, and NF{kappa}B activation. > Protective effects must outweigh PPAR{alpha}-independent tubular toxicities of fibrates.

  6. Energy concentration and positional stability of sonoluminescent bubbles in sulfuric acid for different static pressures.

    PubMed

    Rosselló, Juan Manuel; Dellavale, Damián; Bonetto, Fabián José

    2013-09-01

    In this study we report several experimental and numerical results on the influence of static pressure (P_{0}) over the main parameters in single bubble sonoluminescence (SBSL), using a sulfuric acid aqueous solution (SA) with low concentrations of argon gas dissolved. Bifrequency driving was used in the experiments to enhance spatial stability of the bubbles. The experimental results were compared with simulations provided by a numerical code that models the radial dynamics of the bubbles. The results showed that an increase on the static pressure of the system shifts the Bjerknes instability threshold, allowing the bubble to access higher acoustic pressures (P_{Ac}^{}). Furthermore, a decrease in the measured ambient radius R_{0} and the calculated relative gas concentration c_{∞}/c_{0} were observed. A notorious increment in the bubble collapse violence and energy focusing for P_{0} above 1 bar was achieved. These were mainly indicated by the growth of the bubble expansion ratio (R_{max}/R_{0}), the bubble mechanical energy density, and the maximum bubble wall velocity dR/dt. In agreement with the previous statement, the maximum temperature during the bubble collapse predicted by the model is augmented as well. The use of different harmonics in the ultrasound pressure field regarding energy focusing is also discussed. Finally, we analyzed the stability regions of the R_{0}-P_{Ac}^{} parameter space via numerical predictions for P_{0} above the measured, identifying the shape instabilities as the main limiting agent to obtain further energy concentration in SA systems at high static pressures.

  7. Comparative study on two-step concentrated acid hydrolysis for the extraction of sugars from lignocellulosic biomass.

    PubMed

    Wijaya, Yanuar Philip; Putra, Robertus Dhimas Dhewangga; Widyaya, Vania Tanda; Ha, Jeong-Myeong; Suh, Dong Jin; Kim, Chang Soo

    2014-07-01

    Among all the feasible thermochemical conversion processes, concentrated acid hydrolysis has been applied to break the crystalline structure of cellulose efficiently and scale up for mass production as lignocellulosic biomass fractionation process. Process conditions are optimized by investigating the effect of decrystallization sulfuric acid concentration (65-80 wt%), hydrolysis temperature (80°C and 100°C), hydrolysis reaction time (during two hours), and biomass species (oak wood, pine wood, and empty fruit bunch (EFB) of palm oil) toward sugar recovery. At the optimum process condition, 78-96% sugars out of theoretically extractable sugars have been fractionated by concentrated sulfuric acid hydrolysis of the three different biomass species with 87-90 g/L sugar concentration in the hydrolyzate and highest recalcitrance of pine (softwood) was determined by the correlation of crystallinity index and sugar yield considering reaction severity.

  8. Serum fatty acid binding protein 4, free fatty acids and metabolic risk markers

    PubMed Central

    Karakas, Sidika E.; Almario, Rogelio U.; Kim, Kyoungmi

    2009-01-01

    Fatty acid binding protein (FABP) 4 chaperones free fatty acids (FFA) in the adipocytes during lipolysis. Serum FFA relates to Metabolic Syndrome (METS) and serum FABP4 is emerging as a novel risk marker. In 36 overweight/obese women, serum FABP4 and FFA were measured hourly during 5-hour oral glucose tolerance test (OGTT). Insulin resistance was determined using frequently sampled intravenous GTT (FS-IVGTT). Serum lipids and inflammation markers were measured at fasting. During OGTT, serum FABP4 decreased by 40%, reaching its nadir at 3h (from 45.3±3.1 to 31.9±1.6 ng/mL) and stayed below the baseline at 5 h (35.9±2.2 ng/mL) (p < 0.0001 for both, compared to the baseline). Serum FFA decreased by 10 fold, reaching a nadir at 2h (from 0.611±0.033 to 0.067±0.004 mmol/L), then rebounded to 0.816±0.035 mmol/ L at 5h (p < 0.001 for both, compared to baseline). Both fasting-FABP4 and nadir-FABP4 correlated with obesity. Nadir-FABP4 correlated also with insulin resistance parameters from FS-IVGTT and with inflammation. Nadir-FFA, but not fasting-FFA, correlated with the METS-parameters. In conclusion, fasting-FABP4 related to metabolic risk markers more strongly than fasting-FFA. Nadir-FABP4 and nadir-FFA measured after glucose loading may provide better risk assessment than the fasting values. PMID:19394980

  9. Leucine-enriched protein feeding does not impair exercise-induced free fatty acid availability and lipid oxidation: beneficial implications for training in carbohydrate-restricted states.

    PubMed

    Impey, Samuel G; Smith, Dominic; Robinson, Amy L; Owens, Daniel J; Bartlett, Jonathan D; Smith, Kenneth; Limb, Marie; Tang, Jonathan; Fraser, William D; Close, Graeme L; Morton, James P

    2015-02-01

    Given that the enhanced oxidative adaptations observed when training in carbohydrate (CHO)-restricted states is potentially regulated through free fatty acid (FFA)-mediated signalling and that leucine-rich protein elevates muscle protein synthesis, the present study aimed to test the hypothesis that leucine-enriched protein feeding enhances circulating leucine concentration but does not impair FFA availability or whole body lipid oxidation during exercise. Nine males cycled for 2 h at 70% VO2peak when fasted (PLACEBO) or having consumed a whey protein solution (WHEY) or a leucine-enriched whey protein gel (GEL), administered as 22 g 1 h pre-exercise, 11 g/h during and 22 g 30 min post-exercise. Total leucine administration was 14.4 g and 6.3 in GEL and WHEY, respectively. Mean plasma leucine concentrations were elevated in GEL (P = 0.001) compared with WHEY and PLACEBO (375 ± 100, 272 ± 51, 146 ± 14 µmol L(-1), respectively). No differences (P = 0.153) in plasma FFA (WHEY 0.53 ± 0.30, GEL 0.45 ± 0.25, PLACEBO 0.65 ± 0.30, mmol L(-1)) or whole body lipid oxidation during exercise (WHEY 0.37 ± 0.26, GEL 0.36 ± 0.24, PLACEBO 0.34 ± 0.24 g/min) were apparent between trials, despite elevated (P = 0.001) insulin in WHEY and GEL compared with PLACEBO (38 ± 16, 35 ± 16, 22 ± 11 pmol L(-1), respectively). We conclude that leucine-enriched protein feeding does not impair FFA availability or whole body lipid oxidation during exercise, thus having practical applications for athletes who deliberately train in CHO-restricted states to promote skeletal muscle adaptations.

  10. Poly(acrylic acid) modified calcium phosphate cements: the effect of the composition of the cement powder and of the molecular weight and concentration of the polymeric acid.

    PubMed

    Majekodunmi, A O; Deb, S

    2007-09-01

    Polymer modified calcium phosphate cements made with cement powders of varying tetracalcium phosphate [TTCP] content were prepared using two different molecular weight fractions of poly(acrylic acid) at four different concentrations. The ratio of the precursors (TTCP:DCPA) in the cement powder was found to influence the initial setting which decreased with increasing concentration of TTCP in the powder phase. It was also observed that cements derived from the higher molecular weight containing PAA yielded significantly (P < 0.05) shorter initial setting time (Ti) than cements containing the lower molecular weight, poly(acrylic acid) [GE7 PAA] The effect of the varying the TTCP content in the three different cement types PCPC-A, PCPC-B and PCPC-C showed that the trends of the compressive strength were specific to the concentration and molecular weight of the poly (acrylic acid). A 20% concentration of Glascol-E7 with a cement powder composed of an equimolar ratio of precursors (PCPC-B) resulted in optimal compressive strength within the range investigated. The TTCP content of the cement powder could also be varied to improve the diametral tensile strengths of the cements; the specific effects however, were again governed by both the concentration and molecular weight of the constituent poly (acrylic acid). The influence of TTCP on both the initial setting time and diametral tensile strength was related to the Ca (2+) ion concentration, which determined the rate and amount of cross-linking in the cement.

  11. Fatty acid rich effluent from acidogenic biohydrogen reactor as substrate for lipid accumulation in heterotrophic microalgae with simultaneous treatment.

    PubMed

    Venkata Mohan, S; Prathima Devi, M

    2012-11-01

    Acid-rich effluent generated from acidogenic biohydrogen production process was evaluated as substrate for lipid synthesis by integrating with heterotrophic cultivation of mixed microalgae. Experiments were performed both with synthetic volatile fatty acids (SVFA) and fermented fatty acids (FFA) from biohydrogen producing reactor. Fatty acid based platform evidenced significant influence on algal growth as well as lipid accumulation by the formation of triglycerides through fatty acid synthesis. Comparatively FFA documented higher biomass and lipid productivity (1.42mg/ml (wet weight); 26.4%) than SVFAs ((HAc+HBu+HPr), 0.60mg/ml; 23.1%). Lipid profiles varied with substrates and depicted 18 types of saturated and unsaturated fatty acids with wide fuel and food characteristics. The observed higher concentrations of Chl b over Chl a supports the biosynthesis of triacylglycerides. Microalgae diversity visualized the presence of lipid accumulating species viz., Scenedesmus sp. and Chlorella sp. Integration of microalgae cultivation with biohydrogen production showed lipid productivity for biodiesel production along with additional treatment.

  12. Whole body cholesterol, fat, and fatty acid concentrations of mice (Mus domesticus) used as a food source.

    PubMed

    Crissey, S D; Slifka, K A; Lintzenich, B A

    1999-06-01

    The concentrations of dry matter, cholesterol, saturated fat, monounsaturated fat, and 29 fatty acids were measured in four size categories of whole mice (Mus domesticus) that are commonly fed to zoo animals. Dry matter increased with age/size of mice, whereas cholesterol decreased with age/size. Significant differences in fatty acid content were found among mice categories with capric, lauric, and myristic acids. Mice categories had similar levels of palmitic, palmitoleic, heptadecenoic, stearic, oleic, linoleic, gamma linolenic, alpha linolenic, eicosenoic, eicosadienoic, arachidonic, docosahexaenoic, and lignoceric acids. Analyzed lipid content of mice exceeded domestic carnivorous animal requirements for linoleic and arachidonic acids. The fatty acid levels in mice were high, falling between published values in beef and fish. Generally, mice contained higher levels of polyunsaturated fatty acids, including the omega-3 fatty acids, and lower levels of saturated fatty acids than beef. Although fatty acid levels met or exceeded some dietary requirements for carnivores and omnivores, a possibility of excessive levels exists that could lead to eye and tissue abnormalities. Furthermore, as the intake of dietary polyunsaturated fatty acids increases, the dietary requirement for vitamin E increases. Thus, it is important that lipid profiles of feeder mice be known and considered when examining captive animal diets.

  13. Effects of cochlear ablation on amino acid concentrations in the chinchilla posteroventral cochlear nucleus, as compared to rat.

    PubMed

    Godfrey, D A; Chen, K; Godfrey, M A; Jin, Y-M; Robinson, K T; Hair, C

    2008-06-12

    Using a microchemical approach, we measured changes of amino acid concentrations in the chinchilla caudal posteroventral cochlear nucleus (PVCN) after cochlear ablation to determine to what extent slow decreases of glutamate and aspartate concentrations after carboplatin treatment resulted from slower effects of cochlear damage in chinchillas than in rats and guinea pigs, as opposed to effects of carboplatin treatment being slower than those of cochlear ablation. Our results indicate that both factors are involved: decreases of glutamate and aspartate concentrations after cochlear ablation are much slower in chinchillas than in rats and guinea pigs, but they are much faster than the decreases after carboplatin treatment. Further, aspartate and glutamate concentrations in the chinchilla caudal PVCN decreased by larger amounts after cochlear ablation than in rats or guinea pigs, and there was a transient increase of aspartate concentration at short survival times. Detailed mapping of amino acid concentrations in the PVCN of a chinchilla with 1 month survival after cochlear ablation and a rat with 7 days' survival indicated that the reductions of glutamate and aspartate occurred throughout the PVCN but were somewhat larger in ventral and caudal parts in chinchilla. Any decreases in the adjacent granular region were very small. There were also sustained bilateral decreases in concentrations of other amino acids, notably GABA and glycine, in the caudal PVCN of cochlea-ablated chinchillas but not rats. The effects of cochlear ablation on the concentrations of most of these other amino acids in chinchilla caudal PVCN differed from those of carboplatin treatment. Thus, although a major effect of auditory nerve damage on the cochlear nucleus-decreases of glutamate and aspartate concentrations-occurs across species and types of lesions, the details of timing and magnitude and the effects on other amino acids can vary greatly.

  14. Enhanced concentrations of citric acid in spring aerosols collected at the Gosan background site in East Asia

    NASA Astrophysics Data System (ADS)

    Jung, Jinsang; Kawamura, Kimitaka

    2011-09-01

    In order to investigate water-soluble dicarboxylic acids and related compounds in the aerosol samples under the Asian continent outflow, total suspended particle (TSP) samples ( n = 32) were collected at the Gosan site in Jeju Island over 2-5 days integration during 23 March-1 June 2007 and 16-24 April 2008. The samples were analyzed for water-soluble dicarboxylic acids, ketocarboxylic acids, and α-dicarbonyls using a capillary gas chromatography technique. We found elevated concentrations of atmospheric citric acid (range: 20-320 ng m -3) in the TSP samples during mid- to late April of 2007 and 2008. To specify the sources of citric acid, dicarboxylic acids and related compounds were measured in the pollen sample collected at the Gosan site (Pollen_Gosan), authentic pollen samples from Japanese cedar ( Cryptomeria) (Pollen_cedar) and Japanese cypress ( Chamaecyparis obtusa) (Pollen_cypress), and tangerine fruit produced from Jeju Island. Citric acid (2790 ng in unit mg of pollen mass) was found as most abundant species in the Pollen_Gosan, followed by oxalic acid (2390 ng mg -1). Although citric acid was not detected in the Pollen_cedar and Pollen_cypress as major species, it was found as a dominant species in the tangerine juice while malic acid was detected as major species in the tangerine peel, followed by oxalic and citric acids. Since Japanese cedar trees are planted around tangerine farms to prevent strong winds from the Pacific Ocean, citric acid that may be directly emitted from tangerine is likely adsorbed on pollens emitted from Japanese cedar and then transported to the Gosan site. Much lower malic/citric acid ratios obtained under cloudy condition than clear condition suggest that malic acid may rapidly decompose to lower molecular weight compounds such as oxalic and malonic acids (

  15. A specific protein-enriched enteral formula decreases cortisolemia and improves plasma albumin and amino acid concentrations in elderly patients

    PubMed Central

    2010-01-01

    Background Old age is associated with an involuntary and progressive but physiological loss of muscle mass. The aim of this study was to evaluate the effects of exclusive consumption for 6 months of a protein-enriched enteral diet with a relatively high content of branched-chain amino acids on albuminemia, cortisolemia, plasma amino acids, insulin resistance, and inflammation biomarkers in elderly patients. Methods Thirty-two patients from the Clinical Nutrition Outpatient Unit at our hospital exclusively consumed a protein-enriched enteral diet for 6 months. Data were collected at baseline and at 3 and 6 months on anthropometric and biochemical parameters and on plasma concentrations of amino acids, cortisol, adrenocorticotropic hormone, urea, creatinine, insulin resistance, and inflammation biomarkers. Results The percentage of patients with albumin concentration below normal cut-off values decreased from 18% to 0% by the end of the study. At 6 months, concentrations of total plasma (p = 0.008) and essential amino acids (p = 0.011), especially branched-chain amino acids (p = 0.031), were higher versus baseline values, whereas 3-methylhistidine (p = 0.001), cortisol (p = 0.001) and adrenocorticotropic hormone (p = 0.004) levels were lower. Conclusions Regular intake of specific protein-enriched enteral formula increases plasma essential amino acids, especially branched-chain amino acids, and decreases cortisol and 3-methylhistidine, while plasma urea and creatinine remain unchanged. PMID:20626909

  16. Impact of dietary branched chain amino acids concentration on broiler chicks during aflatoxicosis.

    PubMed

    Chen, X; Zhang, Q; Applegate, T J

    2016-06-01

    A 20-day trial was conducted to determine the effects of dietary branched-chain amino acids (BCAA) on performance, nutrient digestibility, and gene expression of the mTOR pathway in broiler chicks when exposed to aflatoxin B1 (AFB1). The 6 dietary treatments were arranged in a 2 × 3 factorial with 3 BCAA concentrations (1.16, 1.94, and 2.73%) with or without 1.5 mg/kg AFB1 (1.77 mg/kg analyzed). Each diet was fed to 8 replicate cages (6 chicks per cage) from 6 to 20 d of age. Exposure to AFB1 significantly reduced gain:feed ratio and breast muscle weight (P < 0.05), and tended to decrease cumulative BW gain (P = 0.087), while increasing dietary BCAA improved all performance measures (P ≤ 0.0002), except relative breast muscle weight. Apparent ileal digestibility of N and 9 amino acids were increased by AFB1 (P ≤ 0.05), but were reduced by higher dietary BCAA (P ≤ 0.023). Jejunum histology was not affected by AFB1, while higher dietary BCAA tended to increase villus height (P = 0.08). Additionally, the gene expression of mTOR pathway (mTOR, 4EBP1, and S6K1) from liver and jejunum were not affected by dietary treatments, while muscle expression of S6K1 tended to be increased by AFB1 (P = 0.07). No significant interaction between AFB1 and dietary BCAA were observed for any measures in the current study. Results from this study suggested that feed AFB1 contamination can significantly reduce growth performance and breast muscle growth in broiler chicks at 20 d. Higher BCAA supply may have beneficial impact on bird performance, but this effect is independent of AFB1 exposure.

  17. Severity of experimental traumatic brain injury modulates changes in concentrations of cerebral free amino acids.

    PubMed

    Amorini, Angela Maria; Lazzarino, Giacomo; Di Pietro, Valentina; Signoretti, Stefano; Lazzarino, Giuseppe; Belli, Antonio; Tavazzi, Barbara

    2017-03-01

    In this study, concentrations of free amino acids (FAA) and amino group containing compounds (AGCC) following graded diffuse traumatic brain injury (mild TBI, mTBI; severe TBI, sTBI) were evaluated. After 6, 12, 24, 48 and 120 hr aspartate (Asp), glutamate (Glu), asparagine (Asn), serine (Ser), glutamine (Gln), histidine (His), glycine (Gly), threonine (Thr), citrulline (Cit), arginine (Arg), alanine (Ala), taurine (Tau), γ-aminobutyrate (GABA), tyrosine (Tyr), S-adenosylhomocysteine (SAH), l-cystathionine (l-Cystat), valine (Val), methionine (Met), tryptophane (Trp), phenylalanine (Phe), isoleucine (Ile), leucine (Leu), ornithine (Orn), lysine (Lys), plus N-acetylaspartate (NAA) were determined in whole brain extracts (n = 6 rats at each time for both TBI levels). Sham-operated animals (n = 6) were used as controls. Results demonstrated that mTBI caused modest, transient changes in NAA, Asp, GABA, Gly, Arg. Following sTBI, animals showed profound, long-lasting modifications of Glu, Gln, NAA, Asp, GABA, Ser, Gly, Ala, Arg, Citr, Tau, Met, SAH, l-Cystat, Tyr and Phe. Increase in Glu and Gln, depletion of NAA and Asp increase, suggested a link between NAA hydrolysis and excitotoxicity after sTBI. Additionally, sTBI rats showed net imbalances of the Glu-Gln/GABA cycle between neurons and astrocytes, and of the methyl-cycle (demonstrated by decrease in Met, and increase in SAH and l-Cystat), throughout the post-injury period. Besides evidencing new potential targets for novel pharmacological treatments, these results suggest that the force acting on the brain tissue at the time of the impact is the main determinant of the reactions ignited and involving amino acid metabolism.

  18. Minimal inhibitory concentrations of undissociated lactic, acetic, citric and propionic acid for Listeria monocytogenes under conditions relevant to cheese.

    PubMed

    Wemmenhove, Ellen; van Valenberg, Hein J F; Zwietering, Marcel H; van Hooijdonk, Toon C M; Wells-Bennik, Marjon H J

    2016-09-01

    Minimal inhibitory concentrations (MICs) of undissociated lactic acid were determined for six different Listeria monocytogenes strains at 30 °C and in a pH range of 4.2-5.8. Small increments in pH and acid concentrations were used to accurately establish the growth/no growth limits of L. monocytogenes for these acids. The MICs of undissociated lactic acid in the pH range of 5.2-5.8 were generally higher than at pH 4.6 for the different L. monocytogenes strains. The average MIC of undissociated lactic acid was 5.0 (SD 1.5) mM in the pH range 5.2-5.6, which is relevant to Gouda cheese. Significant differences in MICs of undissociated lactic acid were found between strains of L. monocytogenes at a given pH, with a maximum observed level of 9.0 mM. Variations in MICs were mostly due to strain variation. In the pH range 5.2-5.6, the MICs of undissociated lactic acid were not significantly different at 12 °C and 30 °C. The average MICs of undissociated acetic acid, citric acid, and propionic acid were 19.0 (SD 6.5) mM, 3.8 (SD 0.9) mM, and 11.0 (SD 6.3) mM, respectively, for the six L. monocytogenes strains tested in the pH range 5.2-5.6. Variations in MICs of these organic acids for L. monocytogenes were also mostly due to strain variation. The generated data contribute to improved predictions of growth/no growth of L. monocytogenes in cheese and other foods containing these organic acids.

  19. Metabolic fate of fatty acids involved in ruminal biohydrogenation in sheep fed concentrate or herbage with or without tannins.

    PubMed

    Vasta, V; Mele, M; Serra, A; Scerra, M; Luciano, G; Lanza, M; Priolo, A

    2009-08-01

    A 2 x 2 factorial experiment was carried out to evaluate the effect of herbage or concentrate feeding and dietary tannin supplementation on fatty acid metabolism and composition in sheep ruminal fluid, plasma, and intramuscular fat. Twenty-eight male lambs were divided into 2 equal groups at 45 d of age and kept in individual pens. One group was given exclusively fresh herbage (vetch), and the other group was fed a concentrate-based diet. Within each treatment, one-half of the lambs received supplementation of quebracho powder, providing 4.0% of dietary DM as tannins. Before slaughter, blood samples were collected. The animals were slaughtered at 105 d of age, and ruminal contents and LM were collected. Blood plasma, ruminal fluid, and LM fatty acid composition was determined by gas chromatography. Tannin supplementation reduced (P < 0.05) the concentration of stearic acid (-49%) and increased the concentration of vaccenic acid (+97%) in ruminal fluid from concentrate-fed lambs. Within concentrate- and herbage-based diets, tannin supplementation reduced the accumulation of SFA in blood (P < 0.05) compared with lambs fed the tannin-free diets. When tannins were included in the concentrate, the LM contained 2-fold greater concentrations of rumenic acid compared with the LM of the lambs fed the tannin-free concentrate (0.96 vs. 0.46% of total extracted fatty acids, respectively; P < 0.05). The concentration of PUFA was greater (P < 0.05) and SFA (P < 0.01) less in the LM from lambs fed the tannin-containing diets as compared with the animals receiving the tannin-free diets. These results confirm, in vivo, that tannins reduce ruminal biohydrogenation, as previously reported in vitro. This implies that tannin supplementation could be a useful strategy to increase the rumenic acid and PUFA content and to reduce the SFA in ruminant meats. However, the correct dietary concentration of tannins should be carefully chosen to avoid negative effects on DMI and animal

  20. Effects of dietary sulfur concentration and forage-to-concentrate ratio on ruminal fermentation, sulfur metabolism, and short-chain fatty acid absorption in beef heifers.

    PubMed

    Amat, S; McKinnon, J J; Penner, G B; Hendrick, S

    2014-02-01

    This study evaluated the effects of dietary S concentration and forage-to-concentrate ratio (F:C) on ruminal fermentation, S metabolism, and short-chain fatty acid (SCFA) absorption in beef heifers. Sixteen ruminally cannulated heifers (initial BW 628 ± 48 kg) were used in a randomized complete block design with a 2 × 2 factorial treatment arrangement. The main factors included F:C (4% forage vs. 51% forage, DM basis) and the S concentration, which was modified using differing sources of wheat dried distillers grains with solubles (DDGS) to achieve low- and high-S diets (LS = 0.30% vs. HS = 0.67% S on a DM basis). Elemental S was also added to increase the S content for the HS diets. Serum sulfate concentration from blood, sulfide (S(2-)), and SCFA concentrations from ruminal fluid, hydrogen sulfide (H2S) concentration from the ruminal gas cap, and urinary sulfate concentration were determined. Continuous rumen pH and SCFA (acetate, butyrate, and propionate) absorption were measured. There were no interactions between S concentration and F:C. The F:C did not affect DMI (P = 0.26) or ruminal S metabolite concentrations (P ≥ 0.19), but ruminal pH was lower (P < 0.01) and SCFA absorption was greater (P < 0.01) for low F:C diets. Heifers fed HS diets had less DMI (P < 0.01) but greater ruminal pH (P < 0.01), greater concentrations of ruminal H2S (P < 0.01) and serum sulfate (P < 0.01), and greater urinary sulfate concentration (P < 0.01) and output (P < 0.01) relative to heifers fed LS diets. Ruminal H2S was positively correlated with serum sulfate (r = 0.89; P < 0.01). Ruminal acetate concentration was not affected (P = 0.26) by dietary S concentration. Heifers fed the HS diet had lower (P = 0.01) ruminal propionate concentration and tended to have lower (P = 0.06) butyrate concentration than heifers fed the LS diet. Ruminal acetate was greater (P = 0.01) and butyrate was less (P < 0.01) with the high F:C diet than the low F:C diet. Both HS (P = 0.06) and low F

  1. Short communication: elevated concentrations of oleic acid and long-chain fatty acids in milk fat of multiparous subclinical ketotic cows.

    PubMed

    Van Haelst, Y N T; Beeckman, A; Van Knegsel, A T M; Fievez, V

    2008-12-01

    The objective of this study was to determine whether concentrations of specific fatty acids in milk fat are a candidate for the early detection of subclinical ketosis. The case study included multiparous cows fed a lipogenic diet or a mixed glucogenic:lipogenic diet during the first 9 wk of lactation. Milk fatty acid profiles of cows classified as healthy (n = 8) or as subclinically ketotic (n = 8) based on a blood plasma beta-hydroxybutyrate threshold concentration of 1.2 mmol/L were compared. Subclinically ketotic cows showed an elevated proportion of C18:1 cis-9 in milk fat during the whole registration period.

  2. Eicosopentaneoic Acid and Other Free Fatty Acid Receptor Agonists Inhibit Lysophosphatidic Acid- and Epidermal Growth Factor-Induced Proliferation of Human Breast Cancer Cells

    PubMed Central

    Hopkins, Mandi M.; Zhang, Zhihong; Liu, Ze; Meier, Kathryn E.

    2016-01-01

    Many key actions of ω-3 (n-3) fatty acids have recently been shown to be mediated by two G protein-coupled receptors (GPCRs) in the free fatty acid receptor (FFAR) family, FFA1 (GPR40) and FFA4 (GPR120). n-3 Fatty acids inhibit proliferation of human breast cancer cells in culture and in animals. In the current study, the roles of FFA1 and FFA4 were investigated. In addition, the role of cross-talk between GPCRs activated by lysophosphatidic acid (LPA), and the tyrosine kinase receptor activated by epidermal growth factor (EGF), was examined. In MCF-7 and MDA-MB-231 human breast cancer cell lines, both LPA and EGF stimulated proliferation, Erk activation, Akt activation, and CCN1 induction. LPA antagonists blocked effects of LPA and EGF on proliferation in MCF-7 and MDA-MB-231, and on cell migration in MCF-7. The n-3 fatty acid eicosopentaneoic acid inhibited LPA- and EGF-induced proliferation in both cell lines. Two synthetic FFAR agonists, GW9508 and TUG-891, likewise inhibited LPA- and EGF-induced proliferation. The data suggest a major role for FFA1, which was expressed by both cell lines. The results indicate that n-3 fatty acids inhibit breast cancer cell proliferation via FFARs, and suggest a mechanism involving negative cross-talk between FFARS, LPA receptors, and EGF receptor. PMID:26821052

  3. Eicosopentaneoic Acid and Other Free Fatty Acid Receptor Agonists Inhibit Lysophosphatidic Acid- and Epidermal Growth Factor-Induced Proliferation of Human Breast Cancer Cells.

    PubMed

    Hopkins, Mandi M; Zhang, Zhihong; Liu, Ze; Meier, Kathryn E

    2016-01-26

    Many key actions of ω-3 (n-3) fatty acids have recently been shown to be mediated by two G protein-coupled receptors (GPCRs) in the free fatty acid receptor (FFAR) family, FFA1 (GPR40) and FFA4 (GPR120). n-3 Fatty acids inhibit proliferation of human breast cancer cells in culture and in animals. In the current study, the roles of FFA1 and FFA4 were investigated. In addition, the role of cross-talk between GPCRs activated by lysophosphatidic acid (LPA), and the tyrosine kinase receptor activated by epidermal growth factor (EGF), was examined. In MCF-7 and MDA-MB-231 human breast cancer cell lines, both LPA and EGF stimulated proliferation, Erk activation, Akt activation, and CCN1 induction. LPA antagonists blocked effects of LPA and EGF on proliferation in MCF-7 and MDA-MB-231, and on cell migration in MCF-7. The n-3 fatty acid eicosopentaneoic acid inhibited LPA- and EGF-induced proliferation in both cell lines. Two synthetic FFAR agonists, GW9508 and TUG-891, likewise inhibited LPA- and EGF-induced proliferation. The data suggest a major role for FFA1, which was expressed by both cell lines. The results indicate that n-3 fatty acids inhibit breast cancer cell proliferation via FFARs, and suggest a mechanism involving negative cross-talk between FFARS, LPA receptors, and EGF receptor.

  4. Surface Patterning of Benzene Carboxylic Acids on Graphite: Influence of structure, solvent, and concentration on molecular self-assembly

    NASA Astrophysics Data System (ADS)

    Florio, Gina; Stiso, Kimberly; Campanelli, Joseph; Dessources, Kimberly; Folkes, Trudi

    2012-02-01

    Scanning tunneling microscopy (STM) was used to investigate the molecular self-assembly of four different benzene carboxylic acid derivatives at the liquid/graphite interface: pyromellitic acid (1,2,4,5-benzenetetracarboxylic acid), trimellitic acid (1,2,4-benzenetricarboxylic acid), trimesic acid (1,3,5-benzenetricarboxylic acid), and 1,3,5-benzenetriacetic acid. A range of two dimensional networks are observed that depend sensitively on the number of carboxylic acids present, the nature of the solvent, and the solution concentration. We will describe our recent efforts to determine (a) the preferential two-dimensional structure(s) for each benzene carboxylic acid at the liquid/graphite interface, (b) the thermodynamic and kinetic factors influencing self-assembly (or lack thereof), (c) the role solvent plays in the assembly, (e) the effect of in situ versus ex situ dilution on surface packing density, and (f) the temporal evolution of the self-assembled monolayer. Results of computational analysis of analog molecules and model monolayer films will also be presented to aid assignment of network structures and to provide a qualitative picture of surface adsorption and network formation.

  5. Serum concentrations of amino acids, fatty acids, lipoproteins, vitamins A and E, and minerals in apparently healthy, free-ranging southern giraffe (Giraffa camelopardalis giraffe).

    PubMed

    Schmidt, Debra A; Ball, Ray L; Grobler, Douw; Ellersieck, Mark R; Griffin, Mark E; Citino, Scott B; Bush, Mitchell

    2007-01-01

    This pilot project began establishing a nutritional profile for free-ranging giraffe. The results will be used as a tool to begin assessing the nutritional status of captive giraffe. In October 2004 serum samples were collected opportunistically from seven adult and 17 sub-adult giraffe being anesthetized for different studies. Seventeen animals were from Double Drift Game Reserve and seven animals were from Kariega Private Game Reserve. The serum samples were analyzed for circulating concentrations of amino acids, fatty acids, lipoproteins, vitamins, and minerals. Information from 15 serum samples collected from anesthetized giraffe in Kruger National Park during April and August 2003 was included in the calcium and phosphorus concentration data. No significant differences were identified between genders. Significant differences between locations were identified for concentrations of certain amino acids, fatty acids, and lipoproteins. Differences between locations are likely due to different nutrient concentrations of foods and possibly the result of different animal densities forcing different food choices among locations. This pilot project may expand to include changes in circulating nutrient concentrations for free-ranging giraffe as is influenced by other locations, seasonal food availability, and different giraffe subspecies. Zoo Biol 0:1-13, 2007. (c) 2006 Wiley-Liss, Inc.

  6. Prolactin messenger ribonucleic acid concentrations throughout the ovine estrous cycle: Assessment relative to prolactin serum and pituitary amounts

    SciTech Connect

    Landefeld, T.; Roulia, V.; Bagnell, T.; Ballard, T.; Levitan, I. )

    1991-01-01

    Prolactin (PRL) mRNA concentrations were assessed by nucleic acid hybridization assays in pituitaries of ewes representing the defined stages of the ovine estrous cycle. Concomitantly, pituitary and serum PRL concentrations were measured in these ewes using radioimmunoassays. It was observed that PRL serum, pituitary and mRNA concentrations tended to increase near the time of the gonadotropin preovulatory surge, particularly between 24 hrs before behavioral estrus to 5 hours after estrus. However, the changes in PRL mRNA, serum and pituitary concentrations were shown not to be statistically significant. These data suggest that PRL production during the sheep estrous cycle is maintained without dramatic changes in synthesis or secretion.

  7. Simultaneous determination of nitric acid and uranium concentrations in aqueous solution from measurements of electrical conductivity, density, and temperature

    SciTech Connect

    Spencer, B.B.

    1991-01-01

    Nuclear fuel reprocessing plants handle aqueous solutions of nitric acid and uranium in large quantities. Automatic control of process operations requires reliable measurements of these solutes concentration, but this is difficult to directly measure. Physical properties such as solution density and electrical conductivity vary with solute concentration and temperature. Conductivity, density and temperature can be measured accurately with relatively simple and inexpensive devices. These properties can be used to determine solute concentrations will good correlations. This paper provides the appropriate correlations for solutions containing 2 to 6 Molar (M) nitric acid and 0 to 300 g/L uranium metal at temperatures from 25--90{degrees}C. The equations are most accurate below 5 M nitric acid, due to a broad maximum in the conductivity curve at 6 M. 12 refs., 9 figs., 6 tabs.

  8. Boric acid solution concentration influencing p-type emitter formation in n-type crystalline Si solar cells

    NASA Astrophysics Data System (ADS)

    Singha, Bandana; Singh Solanki, Chetan

    2016-09-01

    Boric acid (BA) is a spin on dopant (BSoD) source which is used to form p+ emitters in n-type c-Si solar cells. High purity boric acid powder (99.99% pure) when mixed with deionized (DI) water can result in high quality p-type emitter with less amount of surface defects. In this work, we have used different concentrations of boric acid solution concentrations to fabricate p-type emitters with sheet resistance values < 90 Ω/□. The corresponding junction depths for the same are less than 500 nm as measured by SIMS analysis. Boron rich layer (BRL), which is considered as detrimental in emitter performance is found to be minimal for BA solution concentration less than 2% and hence useful for p-type emitter formation.

  9. Concentration of metabolizable energy and digestibility of energy, phosphorus, and amino acids in lemna protein concentrate fed to growing pigs.

    PubMed

    Rojas, O J; Liu, Y; Stein, H H

    2014-11-01

    Lemna protein concentrate (LPC; 68.0% CP) is produced by extracting protein from de-oiled and dehydrated biomaterials from plants of the Lemnaceae family and may be used as a protein source for animals. There are, however, no published data on the nutritional value of LPC fed to pigs. Three experiments were, therefore, conducted to determine the concentration of ME, the standardized total tract digestibility (STTD) of P, and the standardized ileal digestibility (SID) of AA in LPC and to compare these values to values for fish meal and soybean meal (SBM). Experiment 1 was conducted to determine the ME of LPC, fish meal, SBM, and corn. Thirty-two barrows (initial BW: 16.8 ± 2.8 kg) were placed in metabolism cages and allotted to a randomized complete block design with 4 diets and 8 replicate pigs per diet. A corn-based diet and 3 diets that contained corn and LPC, fish meal, or SBM were formulated. Feces and urine were collected for 5 d after a 5-d adaptation period, and all samples were analyzed for GE. Results indicated that the concentration of ME was not different among corn, fish meal, and SBM (3,855, 3,904, and 4,184 kcal/kg DM, respectively), but there was a tendency (P = 0.08) for a reduced ME in LPC (3,804 kcal/kg DM) compared with SBM. In Exp. 2, 24 barrows (initial BW: 12.5 ± 2.5 kg) were allotted to a randomized complete block design with 3 diets and 8 replicate pigs per diet and used to determine the STTD of P in LPC, fish meal, and SBM. Three diets that each contained 1 of the 3 test ingredients as the sole source of P were formulated. Pigs were placed in metabolism cages, and feces were collected for 5 d after a 5-d adaptation period. The STTD of P in LPC (72.8%) was not different from the STTD of P in fish meal (65.6%), but tended (P = 0.07) to be greater than in SBM (62.8%). The SID of AA in LPC, SBM, and fish meal was determined in Exp. 3. Eight barrows (initial BW: 21.4 ± 4.0 kg) were equipped with a T-cannula in the distal ileum and randomly

  10. Suberoylanilide hydroxamic acid (SAHA) at subtoxic concentrations increases the adhesivity of human leukemic cells to fibronectin.

    PubMed

    Kuzelová, Katerina; Pluskalová, Michaela; Brodská, Barbora; Otevrelová, Petra; Elknerová, Klára; Grebenová, Dana; Hrkal, Zbynek

    2010-01-01

    Suberoylanilide hydroxamic acid (SAHA) is an inhibitor of histone deacetylases (HDACs) which is being introduced into clinic for the treatment of hematological diseases. We studied the effect of this compound on six human hematopoietic cell lines (JURL-MK1, K562, CML-T1, Karpas-299, HL-60, and ML-2) as well as on normal human lymphocytes and on leukemic primary cells. SAHA induced dose-dependent and cell type-dependent cell death which displayed apoptotic features (caspase-3 activation and apoptotic DNA fragmentation) in most cell types including the normal lymphocytes. At subtoxic concentrations (0.5-1 microM), SAHA increased the cell adhesivity to fibronectin (FN) in all leukemia/lymphoma-derived cell lines but not in normal lymphocytes. This increase was accompanied by an enhanced expression of integrin beta1 and paxillin, an essential constituent of focal adhesion complexes, both at the protein and mRNA level. On the other hand, the inhibition of ROCK protein, an important regulator of cytoskeleton structure, had no consistent effect on SAHA-induced increase in the cell adhesivity. The promotion of cell adhesivity to FN seems to be specific for SAHA as we observed no such effects with other HDAC inhibitors (trichostatin A and sodium butyrate).

  11. Predicting copper concentrations in acid mine drainage: a comparative analysis of five machine learning techniques.

    PubMed

    Betrie, Getnet D; Tesfamariam, Solomon; Morin, Kevin A; Sadiq, Rehan

    2013-05-01

    Acid mine drainage (AMD) is a global problem that may have serious human health and environmental implications. Laboratory and field tests are commonly used for predicting AMD, however, this is challenging since its formation varies from site-to-site for a number of reasons. Furthermore, these tests are often conducted at small-scale over a short period of time. Subsequently, extrapolation of these results into large-scale setting of mine sites introduce huge uncertainties for decision-makers. This study presents machine learning techniques to develop models to predict AMD quality using historical monitoring data of a mine site. The machine learning techniques explored in this study include artificial neural networks (ANN), support vector machine with polynomial (SVM-Poly) and radial base function (SVM-RBF) kernels, model tree (M5P), and K-nearest neighbors (K-NN). Input variables (physico-chemical parameters) that influence drainage dynamics are identified and used to develop models to predict copper concentrations. For these selected techniques, the predictive accuracy and uncertainty were evaluated based on different statistical measures. The results showed that SVM-Poly performed best, followed by the SVM-RBF, ANN, M5P, and KNN techniques. Overall, this study demonstrates that the machine learning techniques are promising tools for predicting AMD quality.

  12. Segregation of acid plume pixels from background water pixels, signatures of background water and dispersed acid plumes, and implications for calculation of iron concentration in dense plumes

    NASA Technical Reports Server (NTRS)

    Bahn, G. S.

    1978-01-01

    Two files of data, obtained with a modular multiband scanner, for an acid waste dump into ocean water, were analyzed intensively. Signatures were derived for background water at different levels of effective sunlight intensity, and for different iron concentrations in the dispersed plume from the dump. The effect of increased sunlight intensity on the calculated iron concentration was found to be relatively important at low iron concentrations and relatively unimportant at high values of iron concentration in dispersed plumes. It was concluded that the basic equation for iron concentration is not applicable to dense plumes, particularly because lower values are indicated at the very core of the plume, than in the surrounding sheath, whereas radiances increase consistently from background water to dispersed plume to inner sheath to innermost core. It was likewise concluded that in the dense plume the iron concentration would probably best be measured by the higher wave length radiances, although the suitable relationship remains unknown.

  13. Suppression of hepatic fatty acid oxidation and food intake in men.

    PubMed

    Kahler, A; Zimmermann, M; Langhans, W

    1999-01-01

    We investigated the effects of the fatty acid oxidation inhibitor etomoxir (ETO) on food intake and on fat and carbohydrate metabolism in two double-blind crossover studies in male, normal-weight subjects. In study 1, ETO (75 mg [+]-racemate) or placebo was given orally 30 min after completion of a standardized, fat-enriched (total energy: 2698 kJ, 40% from fat) lunch. The subjects (n = 15) were isolated from external time cues and free to choose when to eat dinner from an oversized serving (total energy: 6656 kJ, 60% from fat). In study 2, subjects (n = 13) were selected for habitually high fat intake (mean: 44% of energy intake). ETO (150 mg) or placebo was given after an overnight fast, 2.5 h before offering an oversized high fat breakfast (6960 kJ, 72% from fat). In both studies, blood samples were taken and the respiratory quotient (RQ) was measured several times during each test period. In study 1, ETO (75 mg) did not affect the timing and size of the dinner or subjective feelings of hunger and satiety. Although ETO (75 mg) did not affect the RQ, it decreased plasma beta-hydroxybutyrate (BHB) and increased plasma lactate compared with placebo. Plasma triacylglycerols (TG), free fatty acids (FFA), glucose, and insulin were not affected by ETO. In study 2, ETO (150 mg) enhanced hunger feelings and increased the size of the breakfast by 22.7%. ETO did not affect the RQ, but baseline RQ was lower in study 2 than in study 1 (0.83 versus 0.89, P < 0.01). Compared with placebo, ETO (150 mg) decreased plasma BHB and increased plasma FFA and plasma lactate. Baseline plasma concentrations of BHB, FFA, and lactate were higher in study 2 than in study 1 (BHB: 242 versus 81 mumol/L, P < 0.001; FFA: 0.674 versus 0.406 mmol/L, P < 0.01; lactate: 1.08 versus 0.74 mmol/L, P < 0.05). Plasma concentrations of TG, glucose, and insulin were not affected by ETO. The results suggest that inhibition of hepatic fatty acid oxidation stimulates eating in men when baseline fatty acid

  14. New insights into fatty acid modulation of pancreatic beta-cell function.

    PubMed

    Haber, Esther P; Procópio, Joaquim; Carvalho, Carla R O; Carpinelli, Angelo R; Newsholme, Philip; Curi, Rui

    2006-01-01

    Insulin resistance states as found in type 2 diabetes and obesity are frequently associated with hyperlipidemia. Both stimulatory and detrimental effects of free fatty acids (FFA) on pancreatic beta cells have long been recognized. Acute exposure of the pancreatic beta cell to both high glucose concentrations and saturated FFA results in a substantial increase of insulin release, whereas a chronic exposure results in desensitization and suppression of secretion. Reduction of plasma FFA levels in fasted rats or humans severely impairs glucose-induced insulin release but palmitate can augment insulin release in the presence of nonstimulatory concentrations of glucose. These results imply that changes in physiological plasma levels of FFA are important for regulation of beta-cell function. Although it is widely accepted that fatty acid (FA) metabolism (notably FA synthesis and/or formation of LC-acyl-CoA) is necessary for stimulation of insulin secretion, the key regulatory molecular mechanisms controlling the interplay between glucose and fatty acid metabolism and thus insulin secretion are not well understood but are now described in detail in this review. Indeed the correct control of switching between FA synthesis or oxidation may have critical implications for beta-cell function and integrity both in vivo and in vitro. LC-acyl-CoA (formed from either endogenously synthesized or exogenous FA) controls several aspects of beta-cell function including activation of certain types of PKC, modulation of ion channels, protein acylation, ceramide- and/or NO-mediated apoptosis, and binding to and activating nuclear transcriptional factors. The present review also describes the possible effects of FAs on insulin signaling. We have previously reported that acute exposure of islets to palmitate up-regulates some key components of the intracellular insulin signaling pathway in pancreatic islets. Another aspect considered in this review is the potential source of fatty acids

  15. Amorphous-Amorphous Phase Separation of Freeze-Concentrated Protein and Amino Acid Excipients for Lyophilized Formulations.

    PubMed

    Izutsu, Ken-Ichi; Yoshida, Hiroyuki; Shibata, Hiroko; Goda, Yukihiro

    2016-01-01

    The objective of this study was to elucidate the mixing state of proteins and amino acid excipients concentrated in the amorphous non-ice region of frozen solutions. Thermal analysis of frozen aqueous solutions was performed in heating scans before and after a heat treatment. Frozen aqueous solutions containing a protein (e.g., recombinant human albumin, gelatin) or a polysaccharide (dextran) and an amino acid excipient (e.g., L-arginine, L-arginine hydrochloride, L-arginine monophosphate, sodium L-glutamate) at varied mass ratios showed single or double Tg' (glass transition temperature of maximally freeze-concentrated solutes). Some mixture frozen solutions rich in the polymers maintained the single Tg' of the freeze-concentrated amorphous solute-mixture phase. In contrast, amino acid-rich mixture frozen solutions revealed two Tg's that suggested transition of concentrated non-crystalline solute-mixture phase and excipient-dominant phase. Post-freeze heat treatment induced splitting of the Tg' in some intermediate mass ratio mixture solutions. The mixing state of proteins and amino acids varied depending on their structure, salt types, mass ratio, composition of co-solutes (e.g., NaCl) and thermal history. Information on the varied mixing states should be valuable for the rational use of amino acid excipients in lyophilized protein pharmaceuticals.

  16. Quantitative extraction and concentration of synthetic water-soluble acid dyes from aqueous media using a quinine-chloroform solution

    SciTech Connect

    Kobayashi, F.; Ozawa, N.; Hanai, J.; Isobe, M.; Watabe, T.

    1986-12-01

    Twenty-one water-soluble acid dyes, including eleven azo, five triphenylmethane four xanthene, one naphthol derivatives, used at practical concentrations for food coloration, were quantitatively extracted from water and various carbonated beverages into a 0.1 M quinine-chloroform solution in the presence of 0.5 M boric acid by brief shaking. Quantitative extraction of these dyes was also accomplished by the 0.1 M quinine-chloroform solution made conveniently from chloroform, quinine hydrochloride, and sodium hydroxide added successively to water or beverages containing boric acid. Quinine acted as a countercation on the dyes having sulfonic and/or carboxylic acid group(s) to form chloroform-soluble ion-pair complexes. The diacidic base alkaloid interacted with each acid group of mono-, di-, tri-, and tetrasulfonic acid dyes approximately in the ratio 0.8-0.9 to 1. The dyes in the chloroform solution were quantitatively concentrated into a small volume of sodium hydroxide solution also by brief shaking. The convenient quinine-chloroform method was applicable to the quantitative extraction of a mixture of 12 dyes from carbonated beverages, which are all currently used for food coloration. A high-pressure liquid chromatographic method is also presented for the systematic separation and determination of these 12 dyes following their concentration into the aqueous alkaline solution. The chromatogram was monitored by double-wavelength absorptiometry in the visible and ultraviolet ray regions.

  17. Structural evidence for solvent-stabilisation by aspartic acid as a mechanism for halophilic protein stability in high salt concentrations.

    PubMed

    Lenton, Samuel; Walsh, Danielle L; Rhys, Natasha H; Soper, Alan K; Dougan, Lorna

    2016-07-21

    Halophilic organisms have adapted to survive in high salt environments, where mesophilic organisms would perish. One of the biggest challenges faced by halophilic proteins is the ability to maintain both the structure and function at molar concentrations of salt. A distinct adaptation of halophilic proteins, compared to mesophilic homologues, is the abundance of aspartic acid on the protein surface. Mutagenesis and crystallographic studies of halophilic proteins suggest an important role for solvent interactions with the surface aspartic acid residues. This interaction, between the regions of the acidic protein surface and the solvent, is thought to maintain a hydration layer around the protein at molar salt concentrations thereby allowing halophilic proteins to retain their functional state. Here we present neutron diffraction data of the monomeric zwitterionic form of aspartic acid solutions at physiological pH in 0.25 M and 2.5 M concentration of potassium chloride, to mimic mesophilic and halophilic-like environmental conditions. We have used isotopic substitution in combination with empirical potential structure refinement to extract atomic-scale information from the data. Our study provides structural insights that support the hypothesis that carboxyl groups on acidic residues bind water more tightly under high salt conditions, in support of the residue-ion interaction model of halophilic protein stabilisation. Furthermore our data show that in the presence of high salt the self-association between the zwitterionic form of aspartic acid molecules is reduced, suggesting a possible mechanism through which protein aggregation is prevented.

  18. ANALYSIS OF PERFLUORINATED CARBOXYLIC ACIDS IN SOILS: DETECTION AND QUANTITATION ISSUES AT LOW CONCENTRATIONS

    EPA Science Inventory

    Methods were developed for the extraction from soil, identification, confirmation and quantitation by LC/MS/MS of trace levels of perfluorinated octanoic acid (PFOA), perfluorinated nonanoic acid (PFNA) and perfluorinated decanoic acid (PFDA). Whereas PFOA, PFNA and PFDA all can...

  19. Extracellular Loop 2 of the Free Fatty Acid Receptor 2 Mediates Allosterism of a Phenylacetamide Ago-Allosteric ModulatorS⃞

    PubMed Central

    Smith, Nicola J.; Ward, Richard J.; Stoddart, Leigh A.; Hudson, Brian D.; Kostenis, Evi; Ulven, Trond; Morris, Joanne C.; Tränkle, Christian; Tikhonova, Irina G.; Adams, David R.

    2011-01-01

    Allosteric agonists are powerful tools for exploring the pharmacology of closely related G protein-coupled receptors that have nonselective endogenous ligands, such as the short chain fatty acids at free fatty acid receptors 2 and 3 (FFA2/GPR43 and FFA3/GPR41, respectively). We explored the molecular mechanisms mediating the activity of 4-chloro-α-(1-methylethyl)-N-2-thiazolylbenzeneacetamide (4-CMTB), a recently described phenylacetamide allosteric agonist and allosteric modulator of endogenous ligand function at human FFA2, by combining our previous knowledge of the orthosteric binding site with targeted examination of 4-CMTB structure-activity relationships and mutagenesis and chimeric receptor generation. Here we show that 4-CMTB is a selective agonist for FFA2 that binds to a site distinct from the orthosteric site of the receptor. Ligand structure-activity relationship studies indicated that the N-thiazolyl amide is likely to provide hydrogen bond donor/acceptor interactions with the receptor. Substitution at Leu173 or the exchange of the entire extracellular loop 2 of FFA2 with that of FFA3 was sufficient to reduce or ablate, respectively, allosteric communication between the endogenous and allosteric agonists. Thus, we conclude that extracellular loop 2 of human FFA2 is required for transduction of cooperative signaling between the orthosteric and an as-yet-undefined allosteric binding site of the FFA2 receptor that is occupied by 4-CMTB. PMID:21498659

  20. Strategies for automated sample preparation, nucleic acid purification, and concentration of low-target-number nucleic acids in environmental and food processing samples

    NASA Astrophysics Data System (ADS)

    Bruckner-Lea, Cynthia J.; Holman, David A.; Schuck, Beatrice L.; Brockman, Fred J.; Chandler, Darrell P.

    1999-01-01

    The purpose of this work is to develop a rapid, automated system for nucleic acid purification and concentration from environmental and food processing samples. Our current approach involves off-line filtration and cell lysis (ballistic disintegration) functions in appropriate buffers followed by automated nucleic acid capture and purification on renewable affinity matrix microcolumns. Physical cell lysis and renewable affinity microcolumns eliminate the need for toxic organic solvents, enzyme digestions or other time- consuming sample manipulations. Within the renewable affinity microcolumn, we have examined nucleic acid capture and purification efficiency with various microbead matrices (glass, polymer, paramagnetic), surface derivitization (sequence-specific capture oligonucleotides or peptide nucleic acids), and DNA target size and concentration under variable solution conditions and temperatures. Results will be presented comparing automated system performance relative to benchtop procedures for both clean (pure DNA from a laboratory culture) and environmental (soil extract) samples, including results which demonstrate 8 minute purification and elution of low-copy nucleic acid targets from a crude soil extract in a form suitable for PCR or microarray-based detectors. Future research will involve the development of improved affinity reagents and complete system integration, including upstream cell concentration and cell lysis functions and downstream, gene-based detectors. Results of this research will ultimately lead to improved processes and instrumentation for on-line, automated monitors for pathogenic micro-organisms in food, water, air, and soil samples.

  1. Docosahexaenoic Acid Supplementation from Mid-Pregnancy to Parturition Influenced Breast Milk Fatty Acid Concentrations at 1 Month Postpartum in Mexican Women1234

    PubMed Central

    Imhoff‐Kunsch, Beth; Stein, Aryeh D.; Villalpando, Salvador; Martorell, Reynaldo; Ramakrishnan, Usha

    2011-01-01

    (n-3) PUFA, including DHA, are essential for neural development and accumulate extensively in the fetal and infant brain. (n-3) PUFA concentrations in breast milk, which are largely dependent on maternal diet and tissue stores, are correlated with infant PUFA status. We investigated the effect of prenatal DHA supplementation on PUFA concentrations in breast milk at 1 mo postpartum. In a double-blind, randomized, controlled trial conducted in Mexico, pregnant women were supplemented daily with 400 mg DHA or placebo from 18–22 wk gestation to parturition. Fatty acid concentrations in breast milk obtained from 174 women at 1 mo postpartum were determined using GLC and were expressed as % by weight of total detected fatty acids. Breast milk DHA concentrations in the DHA and placebo groups were (mean ± SD) 0.20 ± 0.06 and 0.17 ± 0.07 (P < 0.01), respectively, and those of α-linolenic acid (ALA) were 1.38 ± 0.47 and 1.24 ± 0.46 (P = 0.01), respectively. Concentrations of EPA and arachidonic acid did not differ between groups (P > 0.05). Maternal plasma DHA concentrations at 1 mo postpartum correlated positively with breast milk DHA at 1 mo postpartum in both the placebo and DHA groups (r = 0.4; P < 0.01 for both treatment groups). Prenatal DHA supplementation from 18–22 wk gestation to parturition increased concentrations of DHA and ALA in breast milk at 1 mo postpartum, providing a mechanism through which breast-fed infants could benefit. PMID:21178076

  2. Concentration effects in the nucleophilic reactions of tertiary amines in aqueous solutions: Alkylation of amines with chloroacetic acid

    NASA Astrophysics Data System (ADS)

    Kazantsev, O. A.; Baruta, D. S.; Shirshin, K. V.; Sivokhin, A. P.; Kamorin, D. M.

    2011-03-01

    In alkylations of tertiary amines with chloroacetic acid in aqueous solutions, an increase in the initial concentrations of reagents to a certain level led to an abrupt increase in the initial rates and conversions attained during the control time. Viscosimetric and refractometric data showed that association with reagents occurred in these systems. The structures of associates that determine the character of the concentration effects of the Menschutkin reaction in water were suggested.

  3. Nonsteroidal anti-inflammatory drug flufenamic acid is a potent activator of AMP-activated protein kinase.

    PubMed

    Chi, Yuan; Li, Kai; Yan, Qiaojing; Koizumi, Schuichi; Shi, Liye; Takahashi, Shuhei; Zhu, Ying; Matsue, Hiroyuki; Takeda, Masayuki; Kitamura, Masanori; Yao, Jian

    2011-10-01

    Flufenamic acid (FFA) is a nonsteroidal anti-inflammatory drug (NSAID). It has anti-inflammatory and antipyretic properties. In addition, it modulates multiple channel activities. The mechanisms underlying the pharmacological actions of FFA are presently unclear. Given that AMP-activated protein kinase (AMPK) has both anti-inflammatory and channel-regulating functions, we examined whether FFA induces AMPK activation. 1) Exposure of several different types of cells to FFA resulted in an elevation of AMPKα phosphorylation at Thr172. This effect of FFA was reproduced by functionally and structurally similar mefenamic acid, tolfenamic acid, niflumic acid, and meclofenamic acid. 2) FFA-induced activation of AMPK was largely abolished by the treatment of cells with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid tetrakis(acetoxymethyl ester) (an intracellular Ca(2+) chelator) or depletion of extracellular Ca(2+), whereas it was mimicked by stimulation of cells with the Ca(2+) ionophore 5-(methylamino)-2-({(2R,3R,6S,8S,9R,11R)-3,9,11-trimethyl-8-[(1S)-1-methyl-2-oxo-2-(1H-pyrrol-2-yl)ethyl]-1,7-dioxaspiro[5.5]undec-2-yl}methyl)-1,3-benzoxazole-4-carboxylic acid (A23187) or ionomycin. 3) FFA triggered a rise in intracellular Ca(2+), which was abolished by cyclosporine, a blocker of mitochondrial permeability transition pore. Cyclosporine also abolished FFA-induced activation of AMPK. 4) Inhibition of Ca(2+)/calmodulin-dependent kinase kinase β (CaMKKβ) with 7-oxo-7H-benzimidazo[2,1-a]benz[de]isoquinoline-3-carboxylic acid acetate (STO-609) or down-regulation of CaMKKβ with short interfering RNA largely abrogated FFA-induced activation of AMPK. 5) FFA significantly suppressed nuclear factor-κB activity and inducible nitric-oxide synthase expression triggered by interleukin-1β and tumor necrosis factor α. This suppression was also largely abrogated by STO-609. Taken together, we conclude that FFA induces AMPK activation through the Ca(2+)-CaMKKβ pathway

  4. Omega-3 free fatty acids inhibit tamoxifen-induced cell apoptosis.

    PubMed

    Wu, Shufan; Guo, Yang; Wu, Yikuan; Zhu, Shenglong; He, Zhao; Chen, Yong Q

    2015-04-03

    Fish oil, which contains omega-3 fatty acids mainly in the form of triglycerides, has benefits for reducing breast cancer risk, similar to tamoxifen action. However, it remains to be elucidated whether the combination of omega-3 free fatty acid (ω-3FFA) with tamoxifen leads to improved treatment in breast cancer. In this study, we observed that ω-3FFA induces MCF-7 cell apoptosis to suppress cell growth. The treatment of breast cancer cells with ω-3FFA attenuated tamoxifen-induced cell apoptosis. ω-3FFA and tamoxifen significantly increased Erk1/2 and Akt phosphorylation levels in a dose and time dependent manner. Compared to ω-3FFA alone, the combination of tamoxifen with ω-3FFA significantly increased Erk1/2 and Akt phosphorylation levels. Because Erk1/2 and Akt activation has been linked to tamoxifen-related anti-estrogen resistance in breast cancer patients, these results indicate that ω-3FFA may interfere with the effects of tamoxifen in the prevention of breast cancer risk.

  5. Flufenamic acid decreases neuronal excitability through modulation of voltage-gated sodium channel gating.

    PubMed

    Yau, Hau-Jie; Baranauskas, Gytis; Martina, Marco

    2010-10-15

    The electrophysiological phenotype of individual neurons critically depends on the biophysical properties of the voltage-gated channels they express. Differences in sodium channel gating are instrumental in determining the different firing phenotypes of pyramidal cells and interneurons; moreover, sodium channel modulation represents an important mechanism of action for many widely used CNS drugs. Flufenamic acid (FFA) is a non-steroidal anti-inflammatory drug that has been long used as a blocker of calcium-dependent cationic conductances. Here we show that FFA inhibits voltage-gated sodium currents in hippocampal pyramidal neurons; this effect is dose-dependent with IC(50) = 189 μm. We used whole-cell and nucleated patch recordings to investigate the mechanisms of FFA modulation of TTX-sensitive voltage-gated sodium current. Our data show that flufenamic acid slows down the inactivation process of the sodium current, while shifting the inactivation curve ~10 mV toward more hyperpolarized potentials. The recovery from inactivation is also affected in a voltage-dependent way, resulting in slower recovery at hyperpolarized potentials. Recordings from acute slices demonstrate that FFA reduces repetitive- and abolishes burst-firing in CA1 pyramidal neurons. A computational model based on our data was employed to better understand the mechanisms of FFA action. Simulation data support the idea that FFA acts via a novel mechanism by reducing the voltage dependence of the sodium channel fast inactivation rates. These effects of FFA suggest that it may be an effective anti-epileptic drug.

  6. Raman spectroscopic study of the aging and nitration of actinide processing anion-exchange resins in concentrated nitric acid

    SciTech Connect

    Buscher, C. T.; Donohoe, R. J.; Mecklenburg, S. L.; Berg, J. M.; Tait, C. D.; Morris, D. E. [Chemical Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545

    1999-08-01

    Degradation of two types of anion exchange resins, Dowex 11 and Reillex HPQ, from the action of concentrated nitric acid (4 to 12 M) and radiolysis [from depleted uranium as UO{sub 2}{sup 2+} nitrate species and {sup 239}Pu as Pu(IV) nitrate species] was followed as a function of time with Raman vibrational spectroscopy. Elevated temperatures ({approx}50 degree sign C) were used in the absence of actinide metal loading to simulate longer exposures of the resin to a HNO{sub 3} process stream and waste storage conditions. In the absence of actinide loading, only minor changes in the Dowex resin at acid concentrations {<=}10 M were observed, while at 12 M acid concentration, the emergence of a Raman peak at 1345 cm-1 indicates the addition of nitro functional groups to the resin. Similar studies with the Reillex resin show it to be more resistant to nitric acid attack at all acid concentrations. Incorporation of weakly radioactive depleted uranium as the UO{sub 2}{sup 2+} nitrate species to the ion-exchange sites of Dowex 11 under differing nitric acid concentrations (6 to 12 M) at room temperature showed no Raman evidence of resin degradation or nitration, even after several hundred days of contact. In contrast, Raman spectra for Dowex 11 in the presence of {sup 239}Pu as Pu(IV) nitrate species reveal numerous changes indicating resin alterations, including a new mode at 1345 cm-1 consistent with a Pu(IV)-nitrate catalyzed addition of nitro groups to the resin backbone. (c) 2000 Society for Applied Spectroscopy.

  7. Dye-sensitized solar cells using retinoic acid and carotenoic acids: Dependence of performance on the conjugation length and the dye concentration

    NASA Astrophysics Data System (ADS)

    Wang, Xiao-Feng; Fujii, Ritsuko; Ito, Seigo; Koyama, Yasushi; Yamano, Yumiko; Ito, Masayoshi; Kitamura, Takayuki; Yanagida, Shozo

    2005-11-01

    Titanium oxide-based dye-sensitized solar cells (DSSC) were fabricated by the use of retinoic acid and carotenoic acids having the number of conjugated double bonds, n = 5-13. The incident photon-to-current conversion efficiency, the photocurrent density and the solar energy-to-electricity conversion efficiency exhibited the highest values at n = 7, and then decreased toward both sides. The effects of dilution of CA7 with deoxycholic acid were also examined. The above parameters per unit CA7 concentration progressively increased toward the lowest concentration, which is ascribed to the isolated excitation free from singlet-triplet annihilation in the dye molecules on the TiO 2 layer.

  8. Clofibrate-induced reduction of plasma branched-chain amino acid concentrations impairs glucose tolerance in rats.

    PubMed

    Kadota, Yoshihiro; Kazama, Shunsuke; Bajotto, Gustavo; Kitaura, Yasuyuki; Shimomura, Yoshiharu

    2012-05-01

    It has been reported that branched-chain amino acid (BCAA) administration stimulates glucose uptake into muscles and whole body glucose oxidation in rats. The authors examined the effect of decreased plasma BCAA concentrations induced by clofibrate treatment on glucose tolerance in rats. Since clofibrate, a drug for hyperlipidemia (high serum triglyceride concentration), is a potent inhibitor of the branched-chain α-keto acid dehydrogenase kinase, clofibrate treatment (0.2 g/kg body weight) activated the hepatic branched-chain α-keto acid dehydrogenase complex, resulting in decreased plasma BCAA concentrations by 30% to 50% from the normal level. An intraperitoneal glucose tolerance test was conducted after clofibrate administration, and the results showed that peak plasma glucose concentration and the area under the curve of glucose concentration during the intraperitoneal glucose tolerance test were significantly higher in clofibrate-treated rats than in control rats. This impaired glucose tolerance in the clofibrate-treated rats was ameliorated by administration of BCAAs (0.45 g/kg body weight, leucine:isoleucine:valine = 2:1:1), which kept plasma BCAA concentrations at normal levels during the intraperitoneal glucose tolerance test. These results suggest that plasma BCAAs play an important role in maintaining normal glucose tolerance in rats.

  9. Estimation of organophosphoric acid triesters in soft polyurethane foam using a concentrated sulfuric acid dissolution technique and gas chromatography with flame photometric detection.

    PubMed

    Nagase, Makoto; Toba, Mineki; Kondo, Hiroyuki; Yasuhara, Akio; Hasebe, Kiyoshi

    2003-12-01

    A concentrated sulfuric acid dissolution technique and a GC method are described for the estimation of tributyl phosphate, tris(2-chloroethyl) phosphate, tris(chloropropyl) phosphate, tris(1,3-dichloro-2-propyl) phosphate, triphenyl phosphate and tris(butoxyethyl) phosphate in soft polyurethane foam. A soft polyurethane foam sample containing organophosphoric acid triesters was dissolved in concentrated sulfuric acid. The solution was added to water, where only the polyurethane was separated out. The pH of the solution was adjusted, and organophosphoric acid triesters were extracted with toluene. After purification, the compounds were determined by GC. The detection limits of the organophosphoric acid triesters were 0.3 - 0.9 microg g(-1). The recoveries of the organophosphoric acid triesters from a 0.05 g sample of soft polyurethane foam were 80.0 - 90.0%, when the spiked amounts were 0.25 - 1 microg. The compounds were detected from soft polyurethane foam at the level of 0.4 - 23.3 microg g(-1).

  10. Fiber from a regular diet is directly associated with fecal short-chain fatty acid concentrations in the elderly.

    PubMed

    Cuervo, Adriana; Salazar, Nuria; Ruas-Madiedo, Patricia; Gueimonde, Miguel; González, Sonia

    2013-10-01

    It has recently been suggested that fiber exerts a considerable effect on microbiota composition and on fecal short-chain fatty acid (SCFA) production, the concentration of which in the colon is important for immune regulation and for maintaining gut and overall health. To test the hypothesis that the fiber consumed in a regular diet affects fecal SCFA concentrations in the elderly, the authors investigated the association between different types of fiber intake and fecal SCFA concentrations in 32 institutionalized elderly subjects aged between 76 and 95 years. Food intake was recorded by means of a validated food frequency questionnaire. Total, soluble (pectin and hemicellulose) and insoluble (pectin, hemicellulose, Klason lignin, and cellulose) fiber was determined using Marlett Food Composition Tables. Analysis of acetic, propionic, and butyric acid concentrations was performed using gas chromatography-mass spectrometry. Potato intake was directly associated with SCFA concentrations and apple intake with propionate concentration. Of the fibers, cellulose showed an independent association with acetate and butyrate concentrations, and insoluble pectin explained a part of the variation in propionate. In conclusion, our results provide further evidence regarding the relation between diet and SCFA concentration in the elderly. The identification of an association between the regular intake of foods such as potatoes and the production of SCFAs provides an opportunity to improve public health.

  11. Mechanisms underlying skeletal muscle insulin resistance induced by fatty acids: importance of the mitochondrial function

    PubMed Central

    2012-01-01

    Insulin resistance condition is associated to the development of several syndromes, such as obesity, type 2 diabetes mellitus and metabolic syndrome. Although the factors linking insulin resistance to these syndromes are not precisely defined yet, evidence suggests that the elevated plasma free fatty acid (FFA) level plays an important role in the development of skeletal muscle insulin resistance. Accordantly, in vivo and in vitro exposure of skeletal muscle and myocytes to physiological concentrations of saturated fatty acids is associated with insulin resistance condition. Several mechanisms have been postulated to account for fatty acids-induced muscle insulin resistance, including Randle cycle, oxidative stress, inflammation and mitochondrial dysfunction. Here we reviewed experimental evidence supporting the involvement of each of these propositions in the development of skeletal muscle insulin resistance induced by saturated fatty acids and propose an integrative model placing mitochondrial dysfunction as an important and common factor to the other mechanisms. PMID:22360800

  12. Varying Response of the Concentration and Yield of Soybean Seed Mineral Elements, Carbohydrates, Organic Acids, Amino Acids, Protein, and Oil to Phosphorus Starvation and CO2 Enrichment

    PubMed Central

    Singh, Shardendu K.; Barnaby, Jinyoung Y.; Reddy, Vangimalla R.; Sicher, Richard C.

    2016-01-01

    A detailed investigation of the concentration (e.g., mg g-1 seed) and total yield (e.g., g plant-1) of seed mineral elements and metabolic profile under phosphorus (P) starvation at ambient (aCO2) and elevated carbon dioxide (eCO2) in soybean is limited. Soybean plants were grown in a controlled environment at either sufficient (0.50 mM P, control) or deficient (0.10 and 0.01 mM, P-stress) levels of P under aCO2 and eCO2 (400 and 800 μmol mol-1, respectively). Both the concentration and yield of 36 out of 38 seed components responded to P treatment and on average 25 and 11 components increased and decreased, respectively, in response to P starvation. Concentrations of carbohydrates (e.g., glucose, sugar alcohols), organic acids (e.g., succinate, glycerate) and amino acids increased while oil, and several minerals declined under P deficiency. However, the yield of the majority of seed components declined except several amino acids (e.g., phenylalanine, serine) under P deficiency. The concentration-based relationship between seed protein and oil was negative (r2 = 0.96), whereas yield-based relationship was positive (r2 = 0.99) across treatments. The CO2 treatment also altered the concentration of 28 out of 38 seed components, of which 23 showed decreasing (e.g., sucrose, glucose, citrate, aconitate, several minerals, and amino acids) while C, iron, Mn, glycerate, and oil showed increasing trends at eCO2. Despite a decreased concentration, yields of the majority of seed components were increased in response to eCO2, which was attributable to the increased seed production especially near sufficient P nutrition. The P × CO2 interactions for the concentration of amino acids and the yield of several components were due to the lack of their response to eCO2 under control or the severe P starvation, respectively. Thus, P deficiency primarily reduced the concentration of oil and mineral elements but enhanced a majority of other components. However, seed components yield

  13. Varying Response of the Concentration and Yield of Soybean Seed Mineral Elements, Carbohydrates, Organic Acids, Amino Acids, Protein, and Oil to Phosphorus Starvation and CO2 Enrichment.

    PubMed

    Singh, Shardendu K; Barnaby, Jinyoung Y; Reddy, Vangimalla R; Sicher, Richard C

    2016-01-01

    A detailed investigation of the concentration (e.g., mg g(-1) seed) and total yield (e.g., g plant(-1)) of seed mineral elements and metabolic profile under phosphorus (P) starvation at ambient (aCO2) and elevated carbon dioxide (eCO2) in soybean is limited. Soybean plants were grown in a controlled environment at either sufficient (0.50 mM P, control) or deficient (0.10 and 0.01 mM, P-stress) levels of P under aCO2 and eCO2 (400 and 800 μmol mol(-1), respectively). Both the concentration and yield of 36 out of 38 seed components responded to P treatment and on average 25 and 11 components increased and decreased, respectively, in response to P starvation. Concentrations of carbohydrates (e.g., glucose, sugar alcohols), organic acids (e.g., succinate, glycerate) and amino acids increased while oil, and several minerals declined under P deficiency. However, the yield of the majority of seed components declined except several amino acids (e.g., phenylalanine, serine) under P deficiency. The concentration-based relationship between seed protein and oil was negative (r(2) = 0.96), whereas yield-based relationship was positive (r(2) = 0.99) across treatments. The CO2 treatment also altered the concentration of 28 out of 38 seed components, of which 23 showed decreasing (e.g., sucrose, glucose, citrate, aconitate, several minerals, and amino acids) while C, iron, Mn, glycerate, and oil showed increasing trends at eCO2. Despite a decreased concentration, yields of the majority of seed components were increased in response to eCO2, which was attributable to the increased seed production especially near sufficient P nutrition. The P × CO2 interactions for the concentration of amino acids and the yield of several components were due to the lack of their response to eCO2 under control or the severe P starvation, respectively. Thus, P deficiency primarily reduced the concentration of oil and mineral elements but enhanced a majority of other components. However, seed

  14. Effect of Phosphoric Acid Concentration on the Characteristics of Sugarcane Bagasse Activated Carbon

    NASA Astrophysics Data System (ADS)

    Adib, M. R. M.; Suraya, W. M. S. W.; Rafidah, H.; Amirza, A. R. M.; Attahirah, M. H. M. N.; Hani, M. S. N. Q.; Adnan, M. S.

    2016-07-01

    Impregnation method is one of the crucial steps involved in producing activated carbon using chemical activation process. Chemicals employed in this step is effective at decomposing the structure of material and forming micropores that helps in adsorption of contaminants. This paper explains thorough procedures that have been involved in producing sugarcane bagasse activated carbon (SBAC) by using 5%, 10%, 20%, 30% phosphoric acid (H3PO4) during the impregnation step. Concentration of H3PO4 used in the process of producing SBAC was optimized through several tests including bulk density, ash content, iodine adsorption and pore size diameter and the charactesristic of optimum SBAC produced has been compared with commercial activated carbon (CAC). Batch study has been carried out by using the SBAC produced from optimum condition to investigate the performance of SBAC in removal of turbidity and chemical oxygen demand (COD) from textile wastewater. From characteristic study, SBAC with 30% H3PO4 has shown the optimum value of bulk density, ash content, iodine adsorption and pore size diameter of 0.3023 g cm-3, 4.35%, 974.96 mg/g and 0.21-0.41 µm, respectively. These values are comparable to the characteristics of CAC. Experimental result from the batch study has been concluded that the SBAC has a promising potential in removing turbidity and COD of 75.5% and 66.3%, respectively which was a slightly lower than CAC which were able to remove 82.8% of turbidity and 70% of COD. As a conclusion, the SBAC is comparable with CAC in terms of their characteristics and the capability of removing contaminants from textile wastewater. Therefore, it has a commercial value to be used as an alternative of low-cost material in producing CAC.

  15. Threshold response of stomatal closing ability to l