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End Products (end + products)
Kinds of End Products Selected AbstractsThe Breakdown of Preformed Advanced Glycation End Products Reverses Erectile Dysfunction in Streptozotocin-Induced Diabetic Rats: Preventive Versus Curative TreatmentTHE JOURNAL OF SEXUAL MEDICINE, Issue 2 2006Mustafa F. Usta MD ABSTRACT Objectives., Accumulation of advanced glycation end products (AGEs) has been linked to many of the complications of diabetes mellitus, including erectile dysfunction (ED). Furthermore, it has been demonstrated that inhibitors of AGE formation, such as aminoguanidine, can prevent ED in diabetic animals. However, it is unknown whether late administration of a putative cross-link breaker, ALT-711, can reverse diabetic ED. We therefore compared ALT-711 and aminoguanidine in their ability to reverse ED in diabetic rats. Materials and Methods., Male Sprague,Dawley rats were randomly divided into four groups: (i) age-matched controls; (ii) streptozotocin (STZ)-induced diabetic rats (60 mg/kg; intraperitoneal injection); (iii) STZ diabetic rats treated with ALT-711 (3 mg/kg/day, intraperitoneal injection); and (iv) STZ diabetic rats treated with aminoguanidine (1 gm/L in drinking water) during the final 6 weeks of 12 weeks of induced diabetes. At the end of 12 weeks, erectile response to cavernous nerve stimulation (CNS) was determined. Neuronal nitric oxide synthase (nNOS) contents were measured in all penises, and AGE levels were determined both in penile tissues and in serum samples. Results., Erectile responses to CNS and penile nNOS protein content were significantly reduced, while AGE levels were elevated in the penises and serum of untreated diabetic animals. Treatment with ALT-711, but not with aminoguanidine, reversed ED and nNOS depletion and reduced serum and penile tissue AGE levels. Conclusions., These results suggest that cross-link breakers, such as ALT-711, are the optimal therapeutic approach, compared with treatment with inhibitors of AGE formation, in the reversal of diabetes-related ED. Usta MF, Kendirci M, Gur S, Foxwell NA, Bivalacqua TJ, Cellek S, and Hellstrom WJG. The breakdown of preformed advanced glycation end products reverses erectile dysfunction in streptozotocin-induced diabetic rats: Preventive versus curative treatment. J Sex Med 2006;3:242,252. [source] Receptor for Advanced Glycation End Products in Donor Lungs Is Associated with Primary Graft Dysfunction After Lung TransplantationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 4 2010A. Pelaez Development of primary graft dysfunction (PGD) is associated with poor outcomes after transplantation. We hypothesized that Receptor for Advanced Glycation End-products (RAGE) levels in donor lungs is associated with the development of PGD. Furthermore, we hypothesized that RAGE levels would be increased with PGD in recipients after transplantation. We measured RAGE in bronchoalveolar lavage fluid (BALf) from 25 donors and 34 recipients. RAGE was also detected in biopsies (transbronchial biopsy) from recipients with and without PGD. RAGE levels were significantly higher in donor lungs that subsequently developed sustained PGD versus transplanted lungs that did not display PGD. Donor RAGE level was a predictor of recipient PGD (odds ratio = 1.768 per 0.25 ng/mL increase in donor RAGE level). In addition, RAGE levels remained high for 14 days in those recipients that developed severe graft dysfunction. Recipients may be at higher risk for developing PGD if they receive transplanted organs that have higher levels of soluble RAGE prior to explantation. Moreover, the clinical and pathologic abnormalities associated with PGD posttransplantation are associated with increased RAGE expression. These findings also raise the possibility that targeting the RAGE signaling pathway could be a novel strategy for treatment and/or prevention of PGD. [source] Signalling pathways involved in retinal endothelial cell proliferation induced by advanced glycation end products: inhibitory effect of gliclazideDIABETES OBESITY & METABOLISM, Issue 2 2004J.-C. Mamputu Aim:, We have previously demonstrated that advanced glycation end products (AGEs) stimulate bovine retinal endothelial cell (BREC) proliferation through induction of vascular endothelial growth factor (VEGF) production by these cells. We have also shown that gliclazide, a sulfonylurea which decreases oxidative stress, inhibits this effect. The aim of the present study was to characterize the signalling pathways involved in AGE-induced BREC proliferation and VEGF production and mediating the inhibitory effect of gliclazide on these biological events. Methods:, BRECs were treated or not treated with AGEs in the presence or absence of gliclazide, antioxidants, protein kinase C (PKC), mitogen-activated protein kinase (MAPK) or nuclear factor-,B (NF-,B) inhibitors. BREC proliferation was assessed by measuring [3H]-thymidine incorporation into DNA. Activation of PKC, MAPK and NF-,B signal transduction pathways and determination of VEGF expression were assessed by Western blot analysis using specific antibodies. MAPK activity was also determined by an in vitro kinase assay. Results:, Treatment of BRECs with AGEs significantly increased cell proliferation and VEGF expression. AGEs induced PKC-, translocation, extracellular signal-regulated protein kinase 1/2 and NF-,B activation in these cells. Pharmacological inhibition of these signalling pathways abolished AGE effects on cell proliferation and VEGF expression. Exposure of BRECs to gliclazide or antioxidants such as vitamin E or N -acetyl- l -cysteine resulted in a significant decrease in AGE-induced activation of PKC-, MAPK- and NF-,B-signalling pathways. Conclusions:, Our results demonstrate the involvement of PKC, MAPK and NF-,B in AGE-induced BREC proliferation and VEGF expression. Gliclazide inhibits BREC proliferation by interfering with these intracellular signal transduction pathways. [source] Advanced glycation end products-induced apoptosis attenuated by PPAR, activation and epigallocatechin gallate through NF-,B pathway in human embryonic kidney cells and human mesangial cellsDIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 5 2010Yao-Jen Liang Abstract Background Diabetic nephropathy has attracted many researchers' attention. Because of the emerging evidence about the effects of advanced glycation end products (AGEs) and receptor of AGE (RAGE) on the progression of diabetic nephropathy, a number of different therapies to inhibit AGE or RAGE are under investigation. The purpose of the present study was to examine whether peroxisome proliferator-activated receptor , (PPAR,) agonist (L-165041) or epigallocatechin gallate (EGCG) alters AGE-induced pro-inflammatory gene expression and apoptosis in human embryonic kidney cells (HEK293) and human mesangial cells (HMCs). Methods The HEK cells and HMC were separated into the following groups: 100 µg/mL AGE alone for 18 h; AGE treated with 1 µM L-165041 or 10 µM EGCG, and untreated cells. Inflammatory cytokines, nuclear factor-,B pathway, RAGE expression, superoxide dismutase and cell apoptosis were determined. Results AGE significantly increased tumour necrosis factor-, (TNF-,), a major pro-inflammatory cytokine. The mRNA and protein expression of RAGE were up-regulated. These effects were significantly attenuated by pre-treatment with L-165041 or EGCG. AGE-induced nuclear factor-,B pathway activation and both cells apoptosis were also inhibited by L-165041 or EGCG. Furthermore, both L-165041 and EGCG increased superoxide dismutase levels in AGE-treated HEK cells and HMC. Conclusions This study demonstrated that PPAR, agonist and EGCG decreased the AGE-induced kidney cell inflammation and apoptosis. This study provides important insights into the molecular mechanisms of EGCG and PPAR, agonist in attenuation of kidney cell inflammation and may serve as a therapeutic modality to treat patients with diabetic nephropathy. Copyright © 2010 John Wiley & Sons, Ltd. [source] Metabolic memory in diabetes,focus on insulinDIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 2 2005Derek LeRoith Abstract Large-scale clinical trials have demonstrated that metabolic control achieved early in the course of diabetes substantially reduces development and progression of diabetes and the associated microvascular complications. Additionally, prospective observational studies have demonstrated that atherogenic and inflammatory mediators are elevated even prior to the onset of diabetes and significantly contribute to subsequent development of macrovascular complications. Collectively, these data suggest that metabolic memories are stored early in the course of diabetes. We believe that insulin suppresses inflammation and also suppresses glucotoxicity and lipotoxicity (and the consequences thereof, such as the formation of advanced glycation end products and epigenetic phenomena), and thus has a pivotal and beneficial role. Comprehensive metabolic control, especially when instituted early, may alter the natural history of diabetic complications by affecting this metabolic memory. Thus, our overall goal is to understand in more detail the molecular mechanisms involved in these changes, thereby affording us opportunities to reduce the long-term effects of diabetes. Copyright © 2005 John Wiley & Sons, Ltd. [source] Bioethanol from agricultural waste residuesENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 1 2008Pascale Champagne Abstract Under the Kyoto Protocol, the Government of Canada has committed to reducing its greenhouse gas emissions by 6% from 1990 levels between 2008 and 2012. Ethanol-blended gasolines have the potential to contribute significantly to these emission reductions. Ethanol is derived from biologically renewable resources and can be employed to replace octane enhancers and aromatic hydrocarbons or oxygenates. To date, the ethanol production industry in Canada is comprised mainly of small-scale plants producing ethanol primarily from agricultural crops as feedstock. Research interests in the area of bioethanol production from organic waste materials emerged in the late 1980. Significant advances in lignocellulosic material extraction and enzymatic hydrolysis have been reported in the last decade, however, continued research efforts are essential for the development of technically feasible and economically viable large-scale enzyme-based biomass-to-ethanol conversion processes. This research aims to develop and test an enzyme-based biomass-to-ethanol conversion process, which employs organic waste materials, such as livestock manures, as alternative sources of cellulosic material feedstock. The source of the livestock manure, manure management practices and cellulose extraction procedures have a significant impact on the quantity and quality of the cellulosic materials derived. As such, raw feedstock materials must be carefully characterized to assess the impact of these factors on the yield of bioethanol and residual end products. The success of cellulose-to-ethanol conversion processes for cellulose extracted from these waste materials as feedstock is generally a function of cellulose fiber pretreatment, enzyme selection and operating conditions. These will differ depending on the source of the waste material feedstock. The long-term benefits of this research will be to introduce a sustainable solid waste management strategy for a number of livestock manure and other lignocellulosic waste materials; contribute to the mitigation in greenhouse gases through sustained carbon and nutrient recycling; reduce the potential for water, air, and soil contamination associated with land disposal of organic waste materials; and to broaden the feedstock source of raw materials for the ethanol production industry. © 2007 American Institute of Chemical Engineers Environ Prog, 2008 [source] Aqueous photolysis of 8:2 fluorotelomer alcoholENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2005Suzanne A. Gauthier Abstract The 8:2 fluorotelomer alcohol (8:2 FTOH) was photodegraded in aqueous hydrogen peroxide solutions, synthetic field water (SFW) systems, and Lake Ontario (Canada) water samples. It was found to undergo indirect photolysis, with the data suggesting that the hydroxyl radical was the main degradation agent and that nitrate promoted photolysis whereas dissolved organic carbon inhibited it. The half-lives of 8:2 FTOH were 0.83 ± 0.20 h (10 mM H2O2), 38.0 ± 6.0 h (100 ,M H2O2), 30.5 ± 8.0 to 163.1 ± 3.0 h (SFW systems), and 93.2 ± 10.0 h (Lake Ontario). No significant loss of the parent compound by direct photolysis could be observed. The major monitored products were the 8:2 fluorotelomer aldehyde, the 8:2 fluorotelomer acid (8:2 FTCA), and perfluorooctanoate (PFOA); the minor monitored products were the 8:2 fluorotelomer unsaturated acid (8:2 FTUCA) and perfluorononanoate (PFNA). The intermediates, 8:2 FTCA and 8:2 FTUCA, were photodegraded to verify the degradation pathway, and a mechanism for the photolysis was proposed whereby the end products of the photolysis pathway were PFOA (major) and PFNA (minor). [source] Impact of glucose levels on advanced glycation end products in hemodialysisHEMODIALYSIS INTERNATIONAL, Issue 3 2007Amy Ruth GODFREY Abstract The current obesity epidemic throughout the western world has resulted in a considerable increase in the condition Type II diabetes mellitus. Recently, the World Health Organization has predicted that the global prevalence of Type II will increase from 175 million patients in 2003 to over 350 million by 2030. One of the major consequences of this disorder is renal failure, which presents itself as chronic kidney disease, and can progress to end-stage renal disease. Once diagnosed, patients are generally treated using dialysis due to a shortage of kidney donors. The fundamental process of dialysis still requires improvement because the survival rate of these patients is relatively poor. This has resulted in considerable research into improvements in hemodialysis membranes, and the challenge to find more suitable marker(s) in assessing the efficacy of the dialysis process. A class of compounds highlighted as a possible accumulative toxin is advanced glycation end products or AGEs. This is an article regarding the impact of hemodialysis and hemodiafiltration on glucose and AGE levels within the body and the consequences of a chronic hyperglycemic condition. It also highlights the negative aspects of using dextrose in conventional dialysis solutions (an area that has already been identified by peritoneal dialysis clinicians as problematic). The review concludes by suggesting several possible topics of future research. [source] Advanced glycation end products accumulate in the reproductive tract of men with diabetesINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 4 2009C. Mallidis Summary Light microscopic studies comparing sperm parameters show little association between diabetes and male fertility. However, with the introduction of new analytical techniques, evidence is now emerging of previously undetectable effects of diabetes on sperm function. Specifically, a recent study has found a significantly higher sperm nuclear DNA fragmentation in diabetic men. As advanced glycation end products (AGEs) are important instigators of oxidative stress and cell dysfunction in numerous diabetic complications, we hypothesized that these compounds could also be present in the male reproductive tract. The presence and localization of the most prominent AGE, carboxymethyl-lysine (CML), in the human testis, epididymis and sperm was determined by immunohistochemistry. Parallel ELISA and Western blot analyses were performed to ascertain the amount of CML in seminal plasma and sperm from 13 diabetic and nine non-diabetic subjects. CML immunoreactivity was found throughout the seminiferous epithelium, the nuclei of spermatogonia and spermatocytes, in the basal and principle cells cytoplasm and nuclei of the caput epididymis and on most sperm tails, mid pieces and all cytoplasmic droplets. The acrosomal cap, especially the equatorial band, was prominently stained in diabetic samples only. The amount of CML was significantly higher (p = 0.004) in sperm from non-diabetic men. Considering the known detrimental actions of AGEs in other organs, the presence, location and quantity of CML, particularly the increased expression found in diabetic men, suggest that these compounds may play a hitherto unrecognized role in male infertility. [source] Aromatase and oestrogens in human male germ cellsINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 5 2005SOPHIE LAMBARD Summary The mammalian testis serves two main functions: production of spermatozoa and synthesis of steroids, among them oestrogens are the end products obtained from the irreversible transformation of androgens by aromatase (P450arom). Up today P450arom has been demonstrated in male germ cells of all mammals so far studied (mice, rat, bank vole, bear, monkey). In man Leydig cells and immature germ cells as well as ejaculated spermatozoa express a biologically active aromatase. Moreover germ cells and spermatozoa contain oestrogen receptors (ER- , and ER- ,) and it is of note that a truncated form of ER- , is present in spermatozoa. These observations clearly suggest that oestrogens are likely concerned in various stages of male germ cell development. [source] Protective effect of arjunolic acid against arsenic-induced oxidative stress in mouse brain,JOURNAL OF BIOCHEMICAL AND MOLECULAR TOXICOLOGY, Issue 1 2008Mahua Sinha Abstract Arsenic, a notoriously poisonous metalloid, is ubiquitous in the environment, and it affects nearly all organ systems of animals including humans. The present study was designed to investigate the preventive role of a triterpenoid saponin, arjunolic acid against arsenic-induced oxidative damage in murine brain. Sodium arsenite was selected as a source of arsenic for this study. The free-radical-scavenging activity and the in vivo antioxidant power of arjunolic acid were determined from its 2,2-diphenyl-1-picryl hydrazyl radical scavenging ability and ferric reducing/antioxidant power assay, respectively. Oral administration of sodium arsenite at a dose of 10 mg/kg body weight for 2 days significantly decreased the activities of antioxidant enzymes, superoxide dismutase, catalase, glutathione- S -transferase, glutathione reductase and glutathione peroxidase, the level of cellular metabolites, reduced glutathione, total thiols and increased the level of oxidized glutathione. In addition, it enhanced the levels of lipid peroxidation end products and protein carbonyl content. Treatment with arjunolic acid at a dose of 20 mg/kg body weight for 4 days prior to arsenic administration almost normalized above indices. Histological findings due to arsenic intoxication and arjunolic acid treatment supported the other biochemical changes in murine brains. Results of 2,2-diphenyl-1-picryl hydrazyl radical scavenging and ferric reducing/antioxidant power assays clearly showed the in vitro radical scavenging as well as the in vivo antioxidant power of arjunolic acid, respectively. The effect of a well-established antioxidant, vitamin C, has been included in the study as a positive control. Combining all, results suggest that arjunolic acid possessed the ability to ameliorate arsenic-induced oxidative insult in murine brain and is probably due to its antioxidant activity. © 2008 Wiley Periodicals, Inc. J Biochem Mol Toxicol 22:15,26, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20209 [source] Thioredoxin interacting protein (TXNIP) induces inflammation through chromatin modification in retinal capillary endothelial cells under diabetic conditionsJOURNAL OF CELLULAR PHYSIOLOGY, Issue 1 2009Lorena Perrone Chronic hyperglycemia and activation of receptor for advanced glycation end products (RAGE) are known risk factors for microvascular disease development in diabetic retinopathy. Thioredoxin-interacting protein (TXNIP), an endogenous inhibitor of antioxidant thioredoxin (TRX), plays a causative role in diabetes and its vascular complications. Herein we investigate whether HG and RAGE induce inflammation in rat retinal endothelial cells (EC) under diabetic conditions in culture through TXNIP activation and whether epigenetic mechanisms play a role in inflammatory gene expression. We show that RAGE activation by its ligand S100B or HG treatment of retinal EC induces the expression of TXNIP and inflammatory genes such as Cox2, VEGF-A, and ICAM1. TXNIP silencing by siRNA impedes RAGE and HG effects while stable over-expression of a cDNA for human TXNIP in EC elevates inflammation. p38 MAPK-NF-,B signaling pathway and histone H3 lysine (K) nine modifications are involved in TXNIP-induced inflammation. Chromatin immunoprecipitation (ChIP) assays reveal that TXNIP over-expression in EC abolishes H3K9 tri-methylation, a marker for gene inactivation, and increases H3K9 acetylation, an indicator of gene induction, at proximal Cox2 promoter bearing the NF-,B-binding site. These findings have important implications toward understanding the molecular mechanisms of ocular inflammation and endothelial dysfunction in diabetic retinopathy. J. Cell. Physiol. 221: 262,272, 2009. © 2009 Wiley-Liss, Inc [source] Rapid method for the preparation of an AGE-BSA standard calibrator using thermal glycationJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 1 2005A.D. Bhatwadekar Abstract Estimation of advanced glycation end products (AGEs) by determining fluorescence is based on the use of a standard calibrator prepared by incubating bovine serum albumin (BSA) and glucose at 37°C for 60 days. In the present study we attempted to reduce the duration of incubation to 4 days by increasing the temperature to 50°C. It is noteworthy that incubation at 50°C resulted in the rapid production of an AGE-BSA standard calibrator within 4 days. Aminoguanidine reduced the intensity of the glycation-induced fluorescence, while the addition of lysine intensified the reaction, as shown by the calibrator incubated at 37°C. The protein carbonyl content was shown to increase in the rapidly-formed standard calibrator. Thus we conclude that a simple increase in temperature and the addition of lysine (0.1M) can accelerate the process of glycation-induced fluorescence. This calibrator can be used effectively in fluorescence assays of AGEs. J. Clin. Lab. Anal. 19:11,15, 2005. © 2005 Wiley-Liss, Inc. [source] Association of salivary lysozyme and C-reactive protein with metabolic syndromeJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 9 2010Markku Qvarnstrom Qvarnstrom M, Janket S-J, Jones JA, Jethwani K, Nuutinen P, Garcia RI, Baird AE, Van Dyke TE and Meurman JH. Association of salivary lysozyme and C-reactive protein with metabolic syndrome. J Clin Periodontol 2010; 37: 805,811. doi: 10.1111/j.1600-051X.2010.01605.x. Abstract Introduction: Salivary lysozyme (SLZ) is a proteolytic enzyme secreted by oral leucocytes and contains a domain that has an affinity to advanced glycation end products (AGE). Thus, we hypothesized that SLZ would be associated with metabolic syndrome (metS), a pro-inflammatory state. Methods: Utilizing cross-sectional data from 250 coronary artery disease (CAD) and 250 non-CAD patients, the association of SLZ with metS was tested by logistic regression analyses controlling for age, sex, smoking, total cholesterol and C-reactive protein (CRP) levels. The analyses were stratified by CAD status to control for the possible effects of CAD. Results: MetS was found in 122 persons. The adjusted odds ratio (OR) for metS associated with the highest quartile of SLZ was 1.95 with 95% confidence interval (CI) 1.20,3.12, p -value=0.007, compared with the lower three quartiles combined. Among the 40 subjects with metS but without CAD, the OR was 1.63 (CI: 0.64,4.15, p=0.31), whereas in the CAD group, SLZ was significantly associated with metS [OR=1.96 (1.09,3.52), p=0.02]. In both subgroups, CRP was not significantly associated with metS. Conclusion: SLZ was significantly associated with metS (OR=1.95) independent of CRP level. Future longitudinal research is warranted. [source] Biomarkers of aging in DrosophilaAGING CELL, Issue 4 2010Jake Jacobson Summary Low environmental temperature and dietary restriction (DR) extend lifespan in diverse organisms. In the fruit fly Drosophila, switching flies between temperatures alters the rate at which mortality subsequently increases with age but does not reverse mortality rate. In contrast, DR acts acutely to lower mortality risk; flies switched between control feeding and DR show a rapid reversal of mortality rate. Dietary restriction thus does not slow accumulation of aging-related damage. Molecular species that track the effects of temperatures on mortality but are unaltered with switches in diet are therefore potential biomarkers of aging-related damage. However, molecular species that switch upon instigation or withdrawal of DR are thus potential biomarkers of mechanisms underlying risk of mortality, but not of aging-related damage. Using this approach, we assessed several commonly used biomarkers of aging-related damage. Accumulation of fluorescent advanced glycation end products (AGEs) correlated strongly with mortality rate of flies at different temperatures but was independent of diet. Hence, fluorescent AGEs are biomarkers of aging-related damage in flies. In contrast, five oxidized and glycated protein adducts accumulated with age, but were reversible with both temperature and diet, and are therefore not markers either of acute risk of dying or of aging-related damage. Our approach provides a powerful method for identification of biomarkers of aging. [source] PRODUCTION AND BIOCHEMICAL CHARACTERIZATION OF SCLEROTINIA SCLEROTIORUM ,-AMYLASE ScAmy1: ASSAY IN STARCH LIQUEFACTION TREATMENTSJOURNAL OF FOOD BIOCHEMISTRY, Issue 5 2008IMEN BEN ABDELMALEK KHEDHER ABSTRACT Among the lytic enzymes secreted by the phytopathogen fungus Sclerotinia sclerotiorum, a starch-degrading activity has been isolated and characterized. Two extracellular ,-amylases were produced in culture medium in presence of oats flour as carbons sources. An endoamylase named ScAmy1 was purified to homogeneity by ammonium sulfate precipitation, phosphocellulose and cation exchange high performance liquid chromatographies. Molecular mass of purified ScAmy1 was estimated as 54 kDa. Amylase exhibits maximal activity at pH 5 to 6 and at temperature 60C. ScAmy1 was stable in a pH range of (5,11) and at 50C. Initial activity was still conserved 40%, after heating at 60C during 30 min. In addition, Ca2+activate and stabilize the enzyme. Starch end products were determined as low molecular oligoglucanes, the liquefying power of ScAmy1 was also tested with the Amylograph Brabender, results suggest a suitable application of ScAmy1 in several industrial process. PRACTICAL APPLICATIONS ,-Amylase ScAmy1 was highly produced from Sclerotinia sclerotiorum on oats flour , a cheaper by-agro-substrate product. The enzyme was purified and biochemical characterized. ScAmy1 was applied in starch liquefaction treatments assay. The enzyme allows a decrease in peak viscosity after gelatinization and therefore has an important liquefying power. ScAmy1 has a nearly liquefaction effect on flour compared to the commercial enzyme Novamyl, from Novozymes, donated by Novo Nordisk Co. (Denmark). Enzyme end products were analyzed and identified as oligoglucanes and dextrins. Those are widely applied in food, paper, textile and pharmacological industries. Oligosaccharides are useful as prebiotics as dietary fiber or slowly digestible starch derivatives, and they can be used in form of supplement to certain foodstuffs. [source] GLUTEN QUALITY PREDICTION AND CORRELATION STUDIES IN SPRING WHEATSJOURNAL OF FOOD QUALITY, Issue 4 2007IMRAN PASHA ABSTRACT Gluten, "cohesive, viscoelastic, proteinaceous material prepared as a by-product of the starch isolation from wheat flour" and the storage and dough-forming protein of wheat flour, is the key to the unique ability of wheat to suit the production of leavened products. Wet gluten was only affected by wheat varieties, while dry gluten was affected by wheat varieties, crop years and their interaction. The wet and dry gluten ranged 8.0,43.13% and 2.58,14.55%, respectively, and were positively correlated with Zeleny value, sodium dodecyl sulfate sedimentation value and falling number. The gluten content was higher in Pavon, SA 42 and Faisalabad 85, while Zeleny value was higher in GA 02 and C 518, resulting in better gluten quality. Zeleny value was negatively correlated with crude protein content (r = ,0.1857*). The lowest amount of wet and dry gluten was detected in Triticale and durum wheats as compared to common wheats. Zeleny value and sedimentation value may be used as indicators of gluten content and quality while working on wheats. The information thus collected will be valuable for cereal chemists and wheat breeders for improvements in their future breeding programs. PRACTICAL APPLICATIONS This research work will be a breakthrough and helpful for wheat breeders, growers, millers and bakers for their intended uses as every consumer demand specific wheat quality characteristics for their end products. [source] Meaurement of advanced glycation end products may change NASH managmentJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 9 2007Valerio Nobili [source] Drought Stress and Preharvest Aflatoxin Contamination in Agricultural Commodity: Genetics, Genomics and ProteomicsJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 10 2008Baozhu Guo Abstract Throughout the world, aflatoxin contamination is considered one of the most serious food safety issues concerning health. Chronic problems with preharvest aflatoxin contamination occur in the southern US, and are particularly troublesome in corn, peanut, cottonseed, and tree nuts. Drought stress is a major factor to contribute to preharvest aflatoxin contamination. Recent studies have demonstrated higher concentration of defense or stress-related proteins in corn kernels of resistant genotypes compared with susceptible genotypes, suggesting that preharvest field condition (drought or not drought) influences gene expression differently in different genotypes resulting in different levels of "end products": PR(pathogenesis-related) proteins in the mature kernels. Because of the complexity of Aspergillus -plant interactions, better understanding of the mechanisms of genetic resistance will be needed using genomics and proteomics for crop improvement. Genetic improvement of crop resistance to drought stress is one component and will provide a good perspective on the efficacy of control strategy. Proteomic comparisons of corn kernel proteins between resistant or susceptible genotypes to Aspergillus flavus infection have identified stress-related proteins along with antifungal proteins as associated with kernel resistance. Gene expression studies in developing corn kernels are in agreement with the proteomic studies that defense-related genes could be upregulated or downregulated by abiotic stresses. [source] Advanced glycation end product in familial amyloidotic polyneuropathy (FAP)JOURNAL OF INTERNAL MEDICINE, Issue 4 2000N. Nyhlin Abstract. Nyhlin N, Ando Y, Nagai R, Suhr O, El Sahly M, Terazaki H, Yamashita T, Ando M, Horiuchi S (Umeå University Hospital, Umeå, Sweden and Kumamoto University School of Medicine, Kumamoto, Japan). Advanced glycation end product in familial amyloidotic polyneuropathy (FAP). J Intern Med 2000; 247: 485,492. Objectives. Advanced glycation end products (AGE) are present in amyloid deposits in ,2 -microglobulin amyloidosis, and it has been postulated that glycation of ,2 -microglobulin may be involved in fibril formation. The aim of this paper was to ascertain whether AGE occur in amyloid deposits in familial amyloidotic polyneuropathy (FAP). Setting. Department of Medicine, Umeå University Hospital and First Department of Internal Medicine, Kumamoto University School of Medicine. Design. The presence of AGE was sought immunohistochemically and biochemically in amyloid-rich tissues from patients with FAP. Subjects. Biopsy specimens from nine patients and 10 controls were used for the immunohistochemical analysis. For amyloid preparation, vitreous samples from three FAP patients were used. Results. Immunohistochemical studies using a polyclonal anti-AGE antibody revealed positive immunoreactivity in intestinal materials, but the pattern of reactivity was unevenly distributed; it was often present in the border of amyloid deposits, or surrounding them. Non-amyloid associated immunoreactivity was also observed in a few regions of the specimens, although the AGE-positive structures were situated in areas containing amyloid deposits. Western blotting of purified amyloid from the vitreous body of FAP patients revealed a significant association of AGE with amyloid fibrils. Conclusion. The immunoreactivity for the AGE antibody suggests that AGE may be involved in fibril formation in FAP. [source] Advanced glycation end products: a highly complex set of biologically relevant compounds detected by mass spectrometry,JOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 4 2001Annunziata Lapolla Abstract Structural information on ,AGE-peptides,' a class of substances belonging to advanced glycation end products (AGE) and originating by proteolysis of glycated proteins, was gained through various analytical approaches on the mixture produced by proteinase K digestion of in vitro glycated bovine serum albumin. Both matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) and high-performance liquid chromatography/electrospray ionization mass spectrometry (HPLC/ESI-MS) were employed, and the results were compared with those from conventional spectroscopic methods (UV, fluorescence, gel permeation). The data acquired by the various techniques all depict the digestion mixtures as highly complex, with components exhibiting molecular mass in the range 300,3500 Da. In the analysis of HPLC/ESI-MS data, identification of AGE-peptides was facilitated by 3D mapping. Structural information was gained by means of multiple mass spectrometric experiments. Copyright © 2001 John Wiley & Sons, Ltd. [source] Oxidative Stress Following Traumatic Brain Injury in RatsJOURNAL OF NEUROCHEMISTRY, Issue 5 2000Detection of Free Radical Intermediates, Quantitation of Biomarkers Abstract: Oxidative stress may contribute to many pathophysiologic changes that occur after traumatic brain injury. In the current study, contemporary methods of detecting oxidative stress were used in a rodent model of traumatic brain injury. The level of the stable product derived from peroxidation of arachidonyl residues in phospholipids, 8- epi -prostaglandin F2,, was increased at 6 and 24 h after traumatic brain injury. Furthermore, relative amounts of fluorescent end products of lipid peroxidation in brain extracts were increased at 6 and 24 h after trauma compared with sham-operated controls. The total antioxidant reserves of brain homogenates and water-soluble antioxidant reserves as well as tissue concentrations of ascorbate, GSH, and protein sulfhydryls were reduced after traumatic brain injury. A selective inhibitor of cyclooxygenase-2, SC 58125, prevented depletion of ascorbate and thiols, the two major water-soluble antioxidants in traumatized brain. Electron paramagnetic resonance (EPR) spectroscopy of rat cortex homogenates failed to detect any radical adducts with a spin trap, 5,5-dimethyl-1-pyrroline N -oxide, but did detect ascorbate radical signals. The ascorbate radical EPR signals increased in brain homogenates derived from traumatized brain samples compared with sham-operated controls. These results along with detailed model experiments in vitro indicate that ascorbate is a major antioxidant in brain and that the EPR assay of ascorbate radicals may be used to monitor production of free radicals in brain tissue after traumatic brain injury. [source] Site-specific synthesis of Amadori-modified peptides on solid phaseJOURNAL OF PEPTIDE SCIENCE, Issue 6 2006Andrej Frolov Abstract Glycation of peptides and proteins is a slow chemical reaction of reducing sugars modifying the amino groups. The first intermediates of this nonenzymatic glycosylation are the Amadori products that can undergo further chemical reactions, finally leading to advanced glycation end products (AGEs). The formation of AGEs was not only linked to aging of tissues and organs in general but also to several diseases such as diabetes mellitus and Alzheimer's disease. Because of the importance of these modifications and their potential use as diagnostic markers, a global postsynthetic approach on solid phase was developed. The peptides were synthesized by Fmoc/tBu-chemistry, with the lysine residue to be modified being protected with the very acid-labile methyltrityl group. Incubation of the peptides with D -glucose in DMF at elevated temperatures resulted in product yields of 35%. Neighboring residues with bulky protecting groups reduced the yields only slightly. The major by-products were the unmodified peptide and an oxidation product. Whereas the unmodified peptide eluted before the glycated peptide, all other by-products eluted later in RP-HPLC, allowing simple purification. Copyright © 2005 European Peptide Society and John Wiley & Sons, Ltd. [source] A personal account of the role of peptide research in drug discovery: the case of hepatitis C,JOURNAL OF PEPTIDE SCIENCE, Issue 1 2001Antonello Pessi Abstract Although peptides themselves are not usually the end products of a drug discovery effort, peptide research often plays a key role in many aspects of this process. This will be illustrated by reviewing the experience of peptide research carried out at IRBM in the course of our study of hepatitis C virus (HCV). The target of our work is the NS3/4A protease, which is essential for maturation of the viral polyprotein. After a thorough examination of its substrate specificity we fine-tuned several substrate-derived peptides for enzymology studies, high-throughput screening and as fluorescent probes for secondary binding assays. In the course of these studies we made the key observation: that the protease is inhibited by its own cleavage products. Single analog and combinatorial optimization then derived potent peptide inhibitors. The crucial role of the NS4A cofactor was also addressed. NS4A is a small transmembrane protein, whose central domain is the minimal region sufficient for enzyme activation. Structural studies were performed with a peptide corresponding to the minimal activation domain, with a series of product inhibitors and with both. We found that NS3/4A is an induced fit enzyme, requiring both the cofactor and the substrate to acquire its bioactive conformation; this explained some puzzling results of ,serine-trap' type inhibitors. A more complete study on NS3 activation, however, requires the availability of the full-length NS4A protein. This was prepared by native chemical ligation, after sequence engineering to enhance its solubility; structural studies are in progress. Current work is focused on the P, region of the substrate, which, at variance with the P region, is not used for ground state binding to the enzyme and might give rise to inhibitors showing novel interactions with the enzyme. Copyright © 2001 European Peptide Society and John Wiley & Sons, Ltd. [source] Enlarging the library of poly-(L -lysine citramide) polyelectrolytic drug carriersJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 20 2001Anne-Claude Couffin-Hoarau Abstract Poly-(L -lysine citramide) is a degradable drug carrier of the polyelectrolyte type that is composed of citric acid and L -lysine building blocks. In a previous work, poly-(L -lysine citramide) was synthesized by the interfacial polycondensation of ,-hydroxy acid protected citryl dichloride with COOH-protected lysine diamine. Because of head-to-head and head-to-tail and tail-to-tail linkages in the chains as well as various side reactions such as deprotection of the ,-hydroxy acid moieties and intramolecular imide ring formation, a very large family of degradable polyelectrolyte copolymers was obtained. All the members of this family hydrolytically degrade to the same end products. In this study, another route was explored based on the polycondensation of ,-hydroxy acid protected citric acid pentafluorophenyl diesters, namely, citrobenzal dipentafluorophenyl and citrochloral dipentafluorophenyl with N - N,-trimethylsilylated COOH-protected L -lysine. The resulting polymers were characterized by IR, NMR, and size exclusion chromatographic analyses. The resulting chain structures and repeat units were identified from these characterizations and are discussed as compared with characteristics exhibited by analogous polymers resulting from interfacial polycondensation. Differences observed at the intermediate stage involving protected polymers were largely erased during the final deprotection stage because of imide formation during final hydrolysis under the selected conditions. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3475,3484, 2001 [source] In vitro gas production profile and the formation of end products from non- washable, insoluble washable and soluble washable fractions in some concentrate ingredientsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 7 2007Arash Azarfar Abstract A procedure that mimics washing in the in situ incubation technique, combined with an in vitro gas and volatile fatty acids (VFAs) production technique, was used to verify the assumption that rumen degradation behaviour of material washed out of nylon bags is instantaneous and complete. In a 6 × 4 factorial arrangement of treatments with three replicates, fractions of maize, barley, milo, yellow peas, lupins (a mixture of white and spotted lupins) and round-seeded brown faba beans were subjected to an in vitro incubation technique. Fractions were whole (WHO), non-washable (NWF), insoluble washable (ISWF) and soluble washable (SWF). In a manually operated in vitro fermentation system, another 24 samples of the same substrates were fermented for VFA and ammonia analysis. Except in lupins, ISWF in the concentrate ingredients was very rich in starch. SWF was relatively rich in ash, crude protein, soluble sugars, and a residual unknown fraction but contained only a negligible quantity of starch. Thus, the fermentation characteristics of ISWF were more like WHO and NWF than SWF. Total gas production of SWF was considerably lower than the other fractions. A very rapidly degradable fraction was seen in the first phase of degradation of SWF. The pattern of fermentation end-product formation for SWF differed from that of the other fractions. Copyright © 2007 Society of Chemical Industry [source] Laser Micro Processing of Semiconductors and DielectricsLASER TECHNIK JOURNAL, Issue 1 2008Dielectrics, Drilling, How Lasers Present Solutions to Cutting, Scribing of Semiconductors In 2007 the semiconductor manufacturing industry is expected to make more than $250 billion gross revenue and invest over $40 billion in new equipment. The demand for cheaper and increasingly powerful end products, like PCs, Laptops and MP3 Players is the driving force for further development of production equipment. Barrier breaking picosecond lasers for direct ablation of semiconductors are paving the way for the next generation of such machinery. [source] Growth and pectate-lyase activity of the ruminal bacterium Lachnospira multiparus in the presence of short-chain organic acidsLETTERS IN APPLIED MICROBIOLOGY, Issue 5 2005R.A. Paggi Abstract Aims:, Acetic, propionic, butyric and lactic acids are end products of feed fermentation by rumen microbes. The effects of these short chain acids on growth and pectate-lyase (PL) activity of Lachnospira multiparus were studied. Methods and Results:, The bacterial strain used was L. multiparus D32. Acids were tested between 50 and 300 mmol l,1. Growth and PL activity were measured by the increase in total protein content and by the increase in absorbance at 235 nm in the reaction medium respectively. With the exception of lactic acid, all acids decreased bacterial growth rates; generally, these effects were more pronounced at higher concentrations and with acids of longer chains. PL activity was inhibited by all the acids except by butyric acid at 50 and 100 mmol l,1. Enzyme inhibition increased with the concentrations of the acids and lactic acid was the most inhibitory. Conclusions:, High concentrations of short chain acids can differentially inhibit the growth rate and the PL activity of L. multiparus. Significance and Impact of the Study:, Products of fermentation generated by the ruminal microbiota could modify the degradation of pectic substances by this bacterium. [source] Metabolism of Maillard reaction products by the human gut microbiota , implications for healthMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 9 2006Kieran M. Tuohy Abstract The human colonic microbiota imparts metabolic versatility on the colon, interacts at many levels in healthy intestinal and systemic metabolism, and plays protective roles in chronic disease and acute infection. Colonic bacterial metabolism is largely dependant on dietary residues from the upper gut. Carbohydrates, resistant to digestion, drive colonic bacterial fermentation and the resulting end products are considered beneficial. Many colonic species ferment proteins but the end products are not always beneficial and include toxic compounds, such as amines and phenols. Most components of a typical Western diet are heat processed. The Maillard reaction, involving food protein and sugar, is a complex network of reactions occurring during thermal processing. The resultant modified protein resists digestion in the small intestine but is available for colonic bacterial fermentation. Little is known about the fate of the modified protein but some Maillard reaction products (MRP) are biologically active by, e. g. altering bacterial population levels within the colon or, upon absorption, interacting with human disease mechanisms by induction of inflammatory responses. This review presents current understanding of the interactions between MRP and intestinal bacteria. Recent scientific advances offering the possibility of elucidating the consequences of microbe-MRP interactions within the gut are discussed. [source] Xylitol inhibition of anaerobic acid production by Streptococcus mutans at various pH levelsMOLECULAR ORAL MICROBIOLOGY, Issue 4 2003H. Miyasawa Xylitol inhibits the glycolysis and growth of Streptococcus mutans. We studied the inhibitory effect of xylitol on the acid production of S. mutans at several pH levels under the strictly anaerobic conditions found in the deep layer of dental plaque. Xylitol inhibited the rate of acid production from glucose and changed the profile of acidic end products to formate,acetate dominance, with a decrease in the intracellular level of fructose 1,6-bisphosphate and an intracellular accumulation of xylitol 5-phosphate (X5P). These results were notable at pH 5.5,7.0, but were not evident at pH 5.0. Since the activity of phosphoenolpyruvate phosphotransferase for xylitol was greater at higher pH, it is suggested that xylitol could be incorporated more efficiently at higher pH and that the resultant accumulation of X5P could inhibit the glycolysis of S. mutans more effectively. [source] | ||||||||||||||||||||||||||||||||||||||||