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[PMID]:28764042
[Au] Autor:Del Arco J; Cejudo-Sanches J; Esteban I; Clemente-Suárez VJ; Hormigo D; Perona A; Fernández-Lucas J
[Ad] Endereço:Applied Biotechnology Group, Universidad Europea de Madrid, Urbanización El Bosque, Calle Tajo, s/n, 28670 Villaviciosa de Odón, Madrid, Spain.
[Ti] Título:Enzymatic production of dietary nucleotides from low-soluble purine bases by an efficient, thermostable and alkali-tolerant biocatalyst.
[So] Source:Food Chem;237:605-611, 2017 Dec 15.
[Is] ISSN:0308-8146
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Traditionally, enzymatic synthesis of nucleoside-5'-monophosphates (5'-NMPs) using low water-soluble purine bases has been described as less efficient due to their low solubility in aqueous media. The use of enzymes from extremophiles, such as thermophiles or alkaliphiles, offers the potential to increase solubilisation of these bases by employing high temperatures or alkaline pH. This study describes the cloning, expression and purification of hypoxanthine-guanine-xanthine phosphoribosyltransferase from Thermus thermophilus (TtHGXPRT). Biochemical characterization indicates TtHGXPRT as a homotetramer with excellent activity and stability across a broad range of temperatures (50-90°C) and ionic strengths (0-500mMNaCl), but it also reveals an unusually high activity and stability under alkaline conditions (pH range 8-11). In order to explore the potential of TtHGXPRT as an industrial biocatalyst, enzymatic production of several dietary 5'-NMPs, such as 5'-GMP and 5'-IMP, was carried out at high concentrations of guanine and hypoxanthine.
[Mh] Termos MeSH primário: Nucleotídeos/química
Purinas/química
[Mh] Termos MeSH secundário: Hipoxantina
Pentosiltransferases
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Nucleotides); 0 (Purines); 2TN51YD919 (Hypoxanthine); EC 2.4.2.- (Pentosyltransferases); EC 2.4.2.- (hypoxanthine-guanine-xanthine phosphoribosyltransferase)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171107
[Lr] Data última revisão:
171107
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170803
[St] Status:MEDLINE


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[PMID]:28704682
[Au] Autor:DeVito S; Woodrick J; Song L; Roy R
[Ad] Endereço:Department of Oncology, Georgetown Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC, United States.
[Ti] Título:Mutagenic potential of hypoxanthine in live human cells.
[So] Source:Mutat Res;803-805:9-16, 2017 Oct.
[Is] ISSN:1873-135X
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Hypoxanthine (Hx) is a major DNA lesion generated by deamination of adenine during chronic inflammatory conditions, which is an underlying cause of various diseases including cancer of colon, liver, pancreas, bladder and stomach. There is evidence that deamination of DNA bases induces mutations, but no study has directly linked Hx accumulation to mutagenesis and strand-specific mutations yet in human cells. Using a site-specific mutagenesis approach, we report the first direct evidence of mutation potential and pattern of Hx in live human cells. We investigated Hx-induced mutations in human nonmalignant HEK293 and cancer HCT116 cell lines and found that Hx is mutagenic in both HEK293 and HCT116 cell lines. There is a strand bias for Hx-mediated mutations in both the cell lines; the Hx in lagging strand is more mutagenic than in leading strand. There is also some difference in cell types regarding the strand bias for mutation types; HEK293 cells showed largely deletion (>80%) mutations in both leading and lagging strand and the rest were insertions and A:T→G:C transition mutations in leading and lagging strands, respectively, whereas in HCT116 cells we observed 60% A:T→G:C transition mutations in the leading strand and 100% deletions in the lagging strand. Overall, Hx is a highly mutagenic lesion capable of generating A:T→G:C transitions and large deletions with a significant variation in leading and lagging strands in human cells. In recent meta-analysis study A→G (T→C) mutations were found to be a prominent signature in a variety of cancers, including a majority types that are induced by inflammation. The deletions are known to be a major cause of copy-number variations or CNVs, which is a major underlying cause of many human diseases including mental illness, developmental disorders and cancer. Thus, Hx, a major DNA lesion induced by different deamination mechanisms, has potential to initiate inflammation-driven carcinogenesis in addition to various human pathophysiological consequences.
[Mh] Termos MeSH primário: Dano ao DNA/efeitos dos fármacos
Hipoxantina/toxicidade
Mutagênicos/toxicidade
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Reparo do DNA
Desaminação/efeitos dos fármacos
Células HCT116
Células HEK293
Seres Humanos
Mutagênese Sítio-Dirigida
Mutação
Reprodutibilidade dos Testes
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Mutagens); 2TN51YD919 (Hypoxanthine)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171011
[Lr] Data última revisão:
171011
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170714
[St] Status:MEDLINE


  3 / 2307 MEDLINE  
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[PMID]:28640361
[Au] Autor:Long Y; Sanchez-Espiridion B; Lin M; White L; Mishra L; Raju GS; Kopetz S; Eng C; Hildebrandt MAT; Chang DW; Ye Y; Liang D; Wu X
[Ad] Endereço:Department of Epidemiology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
[Ti] Título:Global and targeted serum metabolic profiling of colorectal cancer progression.
[So] Source:Cancer;123(20):4066-4074, 2017 Oct 15.
[Is] ISSN:1097-0142
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Patients with colorectal adenoma polyps (PLPs) are at higher risk for developing colorectal cancer (CRC). However, the development of improved and robust biomarkers to enable the screening, surveillance, and early detection of PLPs and CRC continues to be a challenge. The aim of this study was to identify biomarkers of progression to CRC through metabolomic profiling of human serum samples with a multistage approach. METHODS: Metabolomic profiling was conducted with the Metabolon platform for 30 CRC patients, 30 PLP patients, and 30 control subjects, and this was followed by the targeted validation of the top metabolites in an additional set of 50 CRC patients, 50 PLP patients, and 50 controls with liquid chromatography-tandem mass spectrometry. Unconditional multivariate logistic regression models, adjusted for covariates, were used to evaluate associations with PLP and CRC risk. RESULTS: For the discovery phase, 404 serum metabolites were detected, with 50 metabolites showing differential levels between CRC patients, PLP patients, and controls (P for trend < .05). After validation, the 3 top metabolites (xanthine, hypoxanthine, and d-mannose) were validated: lower levels of xanthine and hypoxanthine and higher levels of d-mannose were found in PLP and CRC cases versus controls. A further exploratory analysis of metabolic pathways revealed key roles for the urea cycle and caffeine metabolism associated with PLP and CRC risk. In addition, a joint effect of the top metabolites with smoking and a significant interaction with the body mass index were observed. An analysis of the ratio of hypoxanthine levels to xanthine levels indicated an association with CRC progression. CONCLUSIONS: These results suggest the potential utility of circulating metabolites as novel biomarkers for the early detection of CRC. Cancer 2017;123:4066-74. © 2017 American Cancer Society.
[Mh] Termos MeSH primário: Adenoma/sangue
Pólipos do Colo/sangue
Neoplasias Colorretais/sangue
[Mh] Termos MeSH secundário: Adenoma/metabolismo
Adulto
Idoso
Cafeína/metabolismo
Estudos de Casos e Controles
Cromatografia Líquida
Pólipos do Colo/metabolismo
Neoplasias Colorretais/metabolismo
Progressão da Doença
Feminino
Seres Humanos
Hipoxantina/sangue
Pólipos Intestinais/sangue
Pólipos Intestinais/metabolismo
Modelos Logísticos
Masculino
Manose/sangue
Metabolômica
Meia-Idade
Análise Multivariada
Espectrometria de Massas em Tandem
Ureia/metabolismo
Xantina/sangue
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
1AVZ07U9S7 (Xanthine); 2TN51YD919 (Hypoxanthine); 3G6A5W338E (Caffeine); 8W8T17847W (Urea); PHA4727WTP (Mannose)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171011
[Lr] Data última revisão:
171011
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:170623
[St] Status:MEDLINE
[do] DOI:10.1002/cncr.30829


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[PMID]:28583948
[Au] Autor:Gallegos-Monterrosa R; Kankel S; Götze S; Barnett R; Stallforth P; Kovács ÁT
[Ad] Endereço:Terrestrial Biofilms Group, Institute of Microbiology, Friedrich Schiller University Jena, Jena, Germany.
[Ti] Título:Lysinibacillus fusiformis M5 Induces Increased Complexity in Bacillus subtilis 168 Colony Biofilms via Hypoxanthine.
[So] Source:J Bacteriol;199(22), 2017 Nov 15.
[Is] ISSN:1098-5530
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In recent years, biofilms have become a central subject of research in the fields of microbiology, medicine, agriculture, and systems biology, among others. The sociomicrobiology of multispecies biofilms, however, is still poorly understood. Here, we report a screening system that allowed us to identify soil bacteria which induce architectural changes in biofilm colonies when cocultured with We identified the soil bacterium M5 as an inducer of wrinkle formation in colonies mediated by a diffusible signaling molecule. This compound was isolated by bioassay-guided chromatographic fractionation. The elicitor was identified to be the purine hypoxanthine using mass spectrometry and nuclear magnetic resonance (NMR) spectroscopy. We show that the induction of wrinkle formation by hypoxanthine is not dependent on signal recognition by the histidine kinases KinA, KinB, KinC, and KinD, which are generally involved in phosphorylation of the master regulator Spo0A. Likewise, we show that hypoxanthine signaling does not induce the expression of biofilm matrix-related operons and Finally, we demonstrate that the purine permease PbuO, but not PbuG, is necessary for hypoxanthine to induce an increase in wrinkle formation of biofilm colonies. Our results suggest that hypoxanthine-stimulated wrinkle development is not due to a direct induction of biofilm-related gene expression but rather is caused by the excess of hypoxanthine within cells, which may lead to cell stress and death. Biofilms are a bacterial lifestyle with high relevance regarding diverse human activities. Biofilms can be beneficial, for instance, in crop protection. In nature, biofilms are commonly found as multispecies communities displaying complex social behaviors and characteristics. The study of interspecies interactions will thus lead to a better understanding and use of biofilms as they occur outside laboratory conditions. Here, we present a screening method suitable for the identification of multispecies interactions and showcase as a soil bacterium that is able to live alongside and modify the architecture of its biofilms.
[Mh] Termos MeSH primário: Bacillaceae/metabolismo
Bacillus subtilis/fisiologia
Biofilmes/crescimento & desenvolvimento
Hipoxantina/metabolismo
Interações Microbianas
Microbiologia do Solo
[Mh] Termos MeSH secundário: Bacillaceae/isolamento & purificação
Bacillus subtilis/genética
Proteínas de Bactérias/metabolismo
Biofilmes/efeitos dos fármacos
Meios de Cultura/química
Ensaios de Triagem em Larga Escala/métodos
Histidina Quinase/genética
Hipoxantina/isolamento & purificação
Hipoxantina/farmacologia
Hipoxantina/fisiologia
Óperon
Fosforilação
Transdução de Sinais
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Culture Media); 2TN51YD919 (Hypoxanthine); EC 2.7.13.1 (Histidine Kinase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171030
[Lr] Data última revisão:
171030
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170607
[St] Status:MEDLINE


  5 / 2307 MEDLINE  
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[PMID]:28418590
[Au] Autor:Nagaraj V; Skillman L; Li D; Xie Z; Ho G
[Ad] Endereço:School of Engineering and Information Technology, Murdoch University, Murdoch, WA, Australia.
[Ti] Título:Control of biofouling by xanthine oxidase on seawater reverse osmosis membranes from a desalination plant: enzyme production and screening of bacterial isolates from the full-scale plant.
[So] Source:Lett Appl Microbiol;65(1):73-81, 2017 Jul.
[Is] ISSN:1472-765X
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Control of biofouling on seawater reverse osmosis (SWRO) membranes is a major challenge as treatments can be expensive, damage the membrane material and often biocides do not remove the polymers in which bacteria are embedded. Biological control has been largely ignored for biofouling control. The objective of this study was to demonstrate the effectiveness of xanthine oxidase enzyme against complex fouling communities and then identify naturally occurring bacterial strains that produce the free radical generating enzyme. Initially, 64 bacterial strains were isolated from different locations of the Perth Seawater Desalination Plant. In our preceding study, 25/64 isolates were selected from the culture collection as models for biofouling studies, based on their prevalence in comparison to the genomic bacterial community. In this study, screening of these model strains was performed using a nitroblue tetrazolium assay in the presence of hypoxanthine as substrate. Enzyme activity was measured by absorbance. Nine of 25 strains tested positive for xanthine oxidase production, of which Exiguobacterium from sand filters and Microbacterium from RO membranes exhibited significant levels of enzyme production. Other genera that produced xanthine oxidase were Marinomonas, Pseudomonas, Bacillus, Pseudoalteromonas and Staphylococcus. Strain variations were observed between members of the genera Microbacterium and Bacillus. SIGNIFICANCE AND IMPACT OF THE STUDY: Xanthine oxidase, an oxidoreductase enzyme that generates reactive oxygen species, is endogenously produced by many bacterial species. In this study, production of the enzyme by bacterial isolates from a full-scale desalination plant was investigated for potential use as biological control of membrane fouling in seawater desalination. We have previously demonstrated that free radicals generated by a commercially available xanthine oxidase in the presence of a hypoxanthine substrate, effectively dispersed biofilm polysaccharides on industrially fouled membranes. Bacterial xanthine oxidase production in the presence of hypoxanthine may prove to be a cost effective, in situ method for alleviation of fouling.
[Mh] Termos MeSH primário: Bactérias/metabolismo
Hipoxantina/metabolismo
Água do Mar/microbiologia
Purificação da Água/métodos
Xantina Oxidase/metabolismo
[Mh] Termos MeSH secundário: Bactérias/enzimologia
Bactérias/isolamento & purificação
Biofilmes
Incrustação Biológica
Filtração
Membranas Artificiais
Osmose
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Membranes, Artificial); 2TN51YD919 (Hypoxanthine); EC 1.17.3.2 (Xanthine Oxidase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171031
[Lr] Data última revisão:
171031
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170419
[St] Status:MEDLINE
[do] DOI:10.1111/lam.12747


  6 / 2307 MEDLINE  
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[PMID]:28355168
[Au] Autor:Scheepers LE; Boonen A; Pijnenburg W; Bierau J; Staessen JA; Stehouwer CD; Thijs C; Arts IC
[Ad] Endereço:aDivision of Rheumatology, Department of Internal Medicine, Maastricht University Medical CentrebCAPHRI School for Public Health and Primary CarecDepartment of Epidemiology, Maastricht UniversitydDepartment of Clinical Genetics, Maastricht University Medical Centre, Maastricht, The NetherlandseResearch Unit Hypertension and Cardiovascular Epidemiology, KU Leuven Department of Cardiovascular Diseases, Studies Coordinating Centre, University of Leuven, Leuven, BelgiumfDepartment of Internal Medicine, Maasticht University Medical CentergCARIM School for Cardiovascular Diseases, Maastricht University Medical CentrehCARIM School for Cardiovascular Diseases, and MaCSBio Maastricht Centre for Systems Biology, Maastricht University, Maastricht, The Netherlands.
[Ti] Título:Associations of plasma uric acid and purine metabolites with blood pressure in children: the KOALA Birth Cohort Study.
[So] Source:J Hypertens;35(5):982-993, 2017 May.
[Is] ISSN:1473-5598
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:OBJECTIVE: Elevated serum uric acid concentration has been associated with high blood pressure (BP) and hypertension. A putative underlying mechanism is the accumulation of reactive oxygen species when uric acid is generated by an increased enzyme activity of xanthine oxidase (XO). The aims of the present study were to investigate the associations between plasma uric acid concentration, purine metabolite ratios, as proxies for increased XO activity, and SBP and DBP in school-age children. METHODS: Cross-sectional analyses were performed in 246 children (46% boys; mean age 7.1 years) from the Dutch KOALA Birth Cohort Study. Purine metabolites were determined with ultra-performance liquid chromatography-tandem mass spectrometry. During a home visit, a nurse collected a blood sample and measured BP three times; in addition, parents measured their child's BP on three consecutive days, in the morning and evening. Generalized estimating equations were used for analyses while controlling for variables such as sex, age, BMI, physical activity, and dietary intake. RESULTS: In multivariable analysis, uric acid (per SD of 38 µmol/l) was associated with DBP z-scores [sß 0.07; confidence interval (CI), 0.01-1.14], but not with SBP z-scores. Higher ratios of uric acid/xanthine (per SD of 138) (sß 0.09; CI, 0.01-0.17) and xanthine/hypoxanthine (per SD of 321) (sß 0.08; CI, 0.02-0.17) were associated with higher DBP z-scores, but not with SBP z-scores. CONCLUSION: In school-age children, uric acid and the ratios of uric acid/xanthine and xanthine/hypoxanthine were significantly associated with DBP z-scores. Suggesting that, both uric acid concentration and increased XO activity are associated with BP.
[Mh] Termos MeSH primário: Pressão Sanguínea
Hipertensão/sangue
Hipoxantina/sangue
Ácido Úrico/sangue
Xantina Oxidase/metabolismo
Xantina/sangue
[Mh] Termos MeSH secundário: Criança
Estudos de Coortes
Estudos Transversais
Diástole
Feminino
Seres Humanos
Hipertensão/enzimologia
Masculino
Purinas/metabolismo
Sístole
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Purines); 1AVZ07U9S7 (Xanthine); 268B43MJ25 (Uric Acid); 2TN51YD919 (Hypoxanthine); EC 1.17.3.2 (Xanthine Oxidase); W60KTZ3IZY (purine)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170906
[Lr] Data última revisão:
170906
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170330
[St] Status:MEDLINE
[do] DOI:10.1097/HJH.0000000000001270


  7 / 2307 MEDLINE  
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[PMID]:28219521
[Au] Autor:Zutz C; Chiang YM; Faehnrich B; Bacher M; Hellinger R; Kluger B; Wagner M; Strauss J; Rychli K
[Ad] Endereço:Institute for Milk Hygiene, University of Veterinary Medicine Vienna, Vienna, Austria; Research Platform Bioactive Microbial Metabolites, Bioresources and Technologies Campus Tulln, Tulln, Donau, Austria. Electronic address: Christoph.zutz@vetmeduni.ac.at.
[Ti] Título:Butyrate influences intracellular levels of adenine and adenine derivatives in the fungus Penicillium restrictum.
[So] Source:Microbiol Res;197:1-8, 2017 Apr.
[Is] ISSN:1618-0623
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Butyrate, a small fatty acid, has an important role in the colon of ruminants and mammalians including the inhibition of inflammation and the regulation of cell proliferation. There is also growing evidence that butyrate is influencing the histone structure in mammalian cells by inhibition of histone deacetylation. Butyrate shows furthermore an antimicrobial activity against fungi, yeast and bacteria, which is linked to its toxicity at a high concentration. In fungi there are indications that butyrate induces the production of secondary metabolites potentially via inhibition of histone deacetylases. However, information about the influence of butyrate on growth, primary metabolite production and metabolism, besides lipid catabolism, in fungi is scarce. We have identified the filamentous fungus Penicillium (P.) restrictum as a susceptible target for butyrate treatment in an antimicrobial activity screen. The antimicrobial activity was detected only in the mycelium of the butyrate treated culture. We investigated the effect of butyrate ranging from low (0.001mM) to high (30mM), potentially toxic, concentrations on biomass and antimicrobial activity. Butyrate at high concentrations (3 and 30mM) significantly reduced the fungal biomass. In contrast P. restrictum treated with 0.03mM of butyrate showed the highest antimicrobial activity. We isolated three antimicrobial active compounds, active against Staphylococcus aureus, from P. restrictum cellular extracts treated with butyrate: adenine, its derivate hypoxanthine and the nucleoside derivate adenosine. Production of all three compounds was increased at low butyrate concentrations. Furthermore we found that butyrate influences the intracellular level of the adenine nucleoside derivate cAMP, an important signalling molecule in fungi and various organisms. In conclusion butyrate treatment increases the intracellular levels of adenine and its respective derivatives.
[Mh] Termos MeSH primário: Adenina/metabolismo
Anti-Infecciosos/farmacologia
Butiratos/farmacologia
Penicillium/efeitos dos fármacos
Penicillium/metabolismo
[Mh] Termos MeSH secundário: Adenina/biossíntese
Adenosina/química
Adenosina/metabolismo
Biomassa
Cromatografia Líquida de Alta Pressão/métodos
AMP Cíclico/metabolismo
Citoplasma/metabolismo
Hipoxantina/química
Hipoxantina/metabolismo
Testes de Sensibilidade Microbiana
Penicillium/química
Esporos Fúngicos/efeitos dos fármacos
Staphylococcus aureus/efeitos dos fármacos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Infective Agents); 0 (Butyrates); 2TN51YD919 (Hypoxanthine); E0399OZS9N (Cyclic AMP); JAC85A2161 (Adenine); K72T3FS567 (Adenosine)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170501
[Lr] Data última revisão:
170501
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170222
[St] Status:MEDLINE


  8 / 2307 MEDLINE  
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[PMID]:28031169
[Au] Autor:Wijermars LG; Bakker JA; de Vries DK; van Noorden CJ; Bierau J; Kostidis S; Mayboroda OA; Tsikas D; Schaapherder AF; Lindeman JH
[Ad] Endereço:Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands.
[Ti] Título:The hypoxanthine-xanthine oxidase axis is not involved in the initial phase of clinical transplantation-related ischemia-reperfusion injury.
[So] Source:Am J Physiol Renal Physiol;312(3):F457-F464, 2017 Mar 01.
[Is] ISSN:1522-1466
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The hypoxanthine-xanthine oxidase (XO) axis is considered to be a key driver of transplantation-related ischemia-reperfusion (I/R) injury. Whereas interference with this axis effectively quenches I/R injury in preclinical models, there is limited efficacy of XO inhibitors in clinical trials. In this context, we considered clinical evaluation of a role for the hypoxanthine-XO axis in human I/R to be relevant. Patients undergoing renal allograft transplantation were included ( = 40) and classified based on duration of ischemia (short, intermediate, and prolonged). Purine metabolites excreted by the reperfused kidney (arteriovenous differences) were analyzed by the ultra performance liquid chromatography-tandem mass spectrometer (UPLCMS/MS) method and tissue XO activity was assessed by in situ enzymography. We confirmed progressive hypoxanthine accumulation ( < 0.006) during ischemia, using kidney transplantation as a clinical model of I/R. Yet, arteriovenous concentration differences of uric acid and in situ enzymography of XO did not indicate significant XO activity in ischemic and reperfused kidney grafts. Furthermore, we tested a putative association between hypoxanthine accumulation and renal oxidative stress by assessing renal malondialdehyde and isoprostane levels and allantoin formation during the reperfusion period. Absent release of these markers is not consistent with an association between ischemic hypoxanthine accumulation and postreperfusion oxidative stress. On basis of these data for the human kidney we hypothesize that the role for the hypoxanthine-XO axis in clinical I/R injury is less than commonly thought, and as such the data provide an explanation for the apparent limited clinical efficacy of XO inhibitors.
[Mh] Termos MeSH primário: Função Retardada do Enxerto/enzimologia
Hipoxantina/metabolismo
Transplante de Rim/efeitos adversos
Rim/enzimologia
Rim/cirurgia
Traumatismo por Reperfusão/enzimologia
Xantina Oxidase/metabolismo
[Mh] Termos MeSH secundário: Adulto
Idoso
Biomarcadores/sangue
Cromatografia Líquida de Alta Pressão
Função Retardada do Enxerto/diagnóstico
Função Retardada do Enxerto/etiologia
Feminino
Seres Humanos
Masculino
Meia-Idade
Estresse Oxidativo
Espécies Reativas de Oxigênio/sangue
Traumatismo por Reperfusão/diagnóstico
Traumatismo por Reperfusão/etiologia
Transdução de Sinais
Espectrometria de Massas em Tandem
Fatores de Tempo
Resultado do Tratamento
Ácido Úrico/sangue
Xantina Oxidase/sangue
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Biomarkers); 0 (Reactive Oxygen Species); 268B43MJ25 (Uric Acid); 2TN51YD919 (Hypoxanthine); EC 1.17.3.2 (Xanthine Oxidase)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170713
[Lr] Data última revisão:
170713
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161230
[St] Status:MEDLINE
[do] DOI:10.1152/ajprenal.00214.2016


  9 / 2307 MEDLINE  
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[PMID]:27888108
[Au] Autor:Kim YJ; Ryu HM; Choi JY; Cho JH; Kim CD; Park SH; Kim YL
[Ad] Endereço:Division of Nephrology and Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, South Korea; BK21 Plus KNU Biomedical Convergence Program, Department of Biomedical Science, Kyungpook National University, Daegu, South Korea; Cell and Matrix Research Institute, Kyu
[Ti] Título:Hypoxanthine causes endothelial dysfunction through oxidative stress-induced apoptosis.
[So] Source:Biochem Biophys Res Commun;482(4):821-827, 2017 Jan 22.
[Is] ISSN:1090-2104
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Endothelial cell injury and dysfunction caused by reactive oxygen species (ROS) are implicated in the pathogenesis of vascular diseases. ROS are generated and hypoxanthine is degraded by xanthine oxidase. Smoking and alcohol consumption are associated with an increased level of hypoxanthine. We aimed to study the direct role of hypoxanthine in endothelial dysfunction in human umbilical vascular endothelial cells (HUVECs). Hypoxanthine induced cell death and production of ROS. Furthermore, hypoxanthine induced apoptosis through regulation of protein expression related to apoptosis. When cells were pretreated with N-acetylcysteine or a pancaspase inhibitor (Z-VAD-fmk) and stimulated with hypoxanthine, Z-VAD-fmk and N-acetylcysteine prevented hypoxanthine-induced apoptosis by inhibiting the ROS production and caspase pathway. Thus, an increased extracellular concentration of hypoxanthine induces endothelial dysfunction through ROS production and regulates expression of apoptosis-related proteins in HUVECs. These effects are expected to be associated with some vascular diseases.
[Mh] Termos MeSH primário: Apoptose
Células Endoteliais/metabolismo
Hipoxantina/metabolismo
Estresse Oxidativo
[Mh] Termos MeSH secundário: Células Endoteliais/citologia
Células Endoteliais/patologia
Células Endoteliais da Veia Umbilical Humana
Seres Humanos
Espécies Reativas de Oxigênio/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Reactive Oxygen Species); 2TN51YD919 (Hypoxanthine)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170602
[Lr] Data última revisão:
170602
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161127
[St] Status:MEDLINE


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[PMID]:27596401
[Au] Autor:Zhang L; Li Q; Lyu J; Kong C; Song S; Luo Y
[Ad] Endereço:Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China.
[Ti] Título:The impact of stunning methods on stress conditions and quality of silver carp (Hypophthalmichthys molitrix) fillets stored at 4°C during 72h postmortem.
[So] Source:Food Chem;216:130-7, 2017 Feb 01.
[Is] ISSN:0308-8146
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:This study aimed to evaluate different stunning methods [percussion (T1), immersion in ice/water slurry (T2), and gill cut (T3)] on quality and stress conditions of silver carp (Hypophthalmichthys molitrix) fillets stored at 4°C in 72h postmortem. Rigor index (RI%), behavioral analysis, levels of lactic acid and muscle glycogen were measured for stress level evaluation. Meanwhile, sensory assessment, texture properties, cooking loss, adenosine triphosphate (ATP) related compounds, adenosine monophosphate deaminase (ADA) activity, and acid phosphatase (ACP) activity were analyzed. The least stress condition, significantly (P<0.05) higher initial glycogen content was observed in T1. Ice/water stunning reduced the rate of ATP degradation, reflected in the lowest K value during 72h. Aversive behaviors, significantly (P<0.05) higher cooking loss, hypoxanthine riboside (HxR) content, and lower sensory score were observed in T3. The results indicated that gill cut in aquatic processing industry should be avoided for inferior quality and aversive reactions during stunning.
[Mh] Termos MeSH primário: Carpas/crescimento & desenvolvimento
Manipulação de Alimentos/métodos
Armazenamento de Alimentos/métodos
Músculos/metabolismo
Controle de Qualidade
Estresse Fisiológico
[Mh] Termos MeSH secundário: Trifosfato de Adenosina/metabolismo
Animais
Carpas/metabolismo
Temperatura Baixa
Qualidade dos Alimentos
Glicogênio/metabolismo
Hipoxantina/análise
Músculos/citologia
Mudanças Depois da Morte
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
2TN51YD919 (Hypoxanthine); 8L70Q75FXE (Adenosine Triphosphate); 9005-79-2 (Glycogen)
[Em] Mês de entrada:1701
[Cu] Atualização por classe:170110
[Lr] Data última revisão:
170110
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160907
[St] Status:MEDLINE



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