259 research outputs found

    Efeito da aplicação de produtos enológicos na eliminação de Aflatoxinas em vinho branco

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    As aflatoxinas, quimicamente definidas como difuranocumarinas, são metabolitos secundários produzidos principalmente pelas espécies Aspergillus flavus e Aspergillus parasiticus. O presente trabalho teve como objetivo estudar a ação de diferentes tipos de produtos enológicos na remoção de aflatoxinas (B1 e B2) presentes no vinho. A eficácia desses produtos na remoção das referidas micotoxinas foi avaliada utilizando vinho artificialmente contaminado com AFB1 e AFB2. O produto enológico que mostrou ser mais eficaz na remoção destas micotoxinas foi a bentonite, com percentagem de remoção de 100%. O caseinato de potássio também se mostrou eficaz, com percentagem de remoção na ordem dos 70 a 80%. Adicionalmente também se avaliou o impacto destes produtos enológicos sobre as características físico-químicas dos vinhos. Os resultados obtidos podem fornecer informações úteis para o sector vitivinícola, na seleção do produto enológico mais apropriado na remoção das aflatoxinas, reduzindo a toxicidade e melhorando simultaneamente a qualidade e segurança alimentar do vinho

    Effect of the application of oenological products on fumonisin B2 (FB2) reduction/removal in contaminated red and white wines

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    ICFC 2017 - International Conference on Food Contaminants (Book of Abstracts)Fumonisins are mycotoxins produced by species of Fusarium, mainly F. verticillioides and F. proliferatum. Fumonisins have hepatotoxic and nephrotoxic effects in various animals and are also associated to human esophageal cancer [1] thus being classified by the IARC in Group 2 [2]. Chemically, fumonisins are characterized by a 19- or 20-carbon aminopolyhydroxyalkyl chain that is diesterified with propane-1,2,3-tricarboxylic acid groups [3]. Sharing a basic structure, several related groups of fumonisins have been isolated and identified (A, B, C and P). Fumonisins B (FBs) are the major forms found in most food products. Recently they were detected in grapes, musts and wines around the world. It was established an association between Aspergillus niger and the presence of FB2 in grape must and wine. WHO has recommended a maximum tolerable daily intake of 2 mg/kg of body weight to FB1, FB2 and FB3, alone or in combination [4], therefore it is important to prevent and control its occurrence, as well other mycotoxins, in wines [5]. The main objective of this work was to evaluate the ability of different oenological products on FB2 removal of white and red wines. For this purpose, ten commercial oenological fining agents (mineral, synthetic and organic - proteins of animal and vegetable origin) were studied to remove FB2 in white and red wines artificially contaminated with FB2. In addition to the FB2 removal, the effect of these products on wine physicochemical characteristics, namely, flavonoids, non-flavonoids and total phenolic compounds were evaluated. In red wine all products showed low reduction on FB2 removal, being the highest value (30%) achieved by calcium bentonite. The results obtained by the action of these products may be considered as a pioneer approach on wine FB2 reduction/removal, with relevance for wine industry, in order to select the best fining agent to reduce toxicity and consequently to improve wine quality and safety.info:eu-repo/semantics/publishedVersio

    X-ray induced ultrafast charge transfer in thiophene-based conjugated polymers controlled by core-hole clock spectroscopy

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    We explore ultrafast charge transfer (CT) resonantly induced by hard X-ray radiation in organic thiophene-based polymers at the sulfur K-edge. A combination of core-hole clock spectroscopy with real-time propagation time-dependent density functional theory simulations gives an insight into the electron dynamics underlying the CT process. Our method provides control over CT by a selective excitation of a specific resonance in the sulfur atom with monochromatic X-ray radiation. Our combined experimental and theoretical investigation establishes that the dominant mechanism of CT in polymer powders and films consists of electron delocalisation along the polymer chain occurring on the low-femtosecond time scale

    Vitamin D Modulates Hematological Parameters and Cell Migration into Peritoneal and Pulmonary Cavities in Alloxan-Diabetic Mice

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    Background/Aims. The effects of cholecalciferol supplementation on the course of diabetes in humans and animals need to be better understood. Therefore, this study investigated the effect of short-term cholecalciferol supplementation on biochemical and hematological parameters in mice. Methods. Male diabetic (alloxan, 60mg/kg i.v., 10 days) and non diabetic mice were supplemented with cholecalciferol for seven days. The following parameters were determined: serum levels of 25-hydroxyvitamin D, phosphorus, calcium, urea, creatinine, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, red blood cell count, white blood cell count (WBC), hematocrit, hemoglobin, differential cell counts of peritoneal lavage (PeL), and bronchoalveolar lavage (BAL) fluids and morphological analysis of lung, kidney, and liver tissues. Results. Relative to controls, cholecalciferol supplementation increased serum levels of 25-hydroxyvitamin D, calcium, hemoglobin, hematocrit, and red blood cell counts and decreased leukocyte cell counts of PeL and BAL fluids in diabetic mice. Diabetic mice that were not treated with cholecalciferol had lower serum calcium and albumin levels and hemoglobin, WBC, and mononuclear blood cell counts and higher serum creatinine and urea levels than controls. Conclusion. Our results suggest that cholecalciferol supplementation improves the hematological parameters and reduces leukocyte migration into the PeL and BAL lavage of diabetic mice.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Pro-reitoria de Pesquisa da Universidade de Sao Paulo (PRP/USP, Projeto I and Novos Docentes)Univ Sao Paulo, Fac Pharmaceut Sci, Dept Clin & Toxicol Anal, Lab Immunoendocrinol,FCF, Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Dept Med, Rheumatol Div, Sao Paulo, SP, BrazilDepartment of Medicine, Rheumatology Division, Universidade Federal de São Paulo, São Paulo, SP, BrazilFAPESP: 2010/02272-0FAPESP: 2012/23998-4FAPESP: 2013/20904-1FAPESP: 2014/05214-1FAPESP: 2017/05100-4CNPq: 470523/2013-1CNPq: 301617/2016-3Web of Scienc

    Rickettsial infection in Amblyomma cajennense ticks and capybaras (Hydrochoerus hydrochaeris) in a Brazilian spotted fever-endemic area

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    Brazilian spotted fever (BSF), caused by the bacterium Rickettsia rickettsii, is the deadliest spotted fever of the world. In most of the BSF-endemic areas, capybaras (Hydrochoerus hydrochaeris) are the principal host for the tick Amblyomma cajennense, which is the main vector of BSF. In 2012, a BSF case was confirmed in a child that was bitten by ticks in a residential park area inhabited by A. cajennense-infested capybaras in Itú municipality, southeastern Brazil. Host questing A. cajennense adult ticks were collected in the residential park and brought alive to the laboratory, where they were macerated and intraperitoneally inoculated into guinea pigs. A tick-inoculated guinea pig that presented high fever was euthanized and its internal organs were macerated and inoculated into additional guinea pigs (guinea pig passage). Tissue samples from guinea pig passages were also used to inoculate Vero cells through the shell vial technique. Infected cells were used for molecular characterization of the rickettsial isolate through PCR and DNA sequencing of fragments of three rickettsial genes (gltA, ompA, and ompB). Blood serum samples were collected from 172 capybaras that inhabited the residential park. Sera were tested through the immunofluorescence assay using R. rickettsii antigen. A tick-inoculated guinea pig presented high fever accompanied by scrotal reactions (edema and marked redness). These signs were reproduced by consecutive guinea pig passages. Rickettsia was successfully isolated in Vero cells that were inoculated with brain homogenate derived from a 3rd passage-febrile guinea pig. Molecular characterization of this rickettsial isolate (designated as strain ITU) yielded DNA sequences that were all 100% identical to corresponding sequences of R. rickettsii in Genbank. A total of 83 (48.3%) out of 172 capybaras were seroreactive to R. rickettsii, with endpoint titers ranging from 64 to 8192. A viable isolate of R. rickettsii was obtained from the tick A. cajennense, comprising the first viable R. rickettsi isolate from this tick species during the last 60 years. Nearly half of the capybara population of the residential park was seroreactive to R. rickettsii, corroborating the findings that the local A. cajennense population was infected by R. rickettsii.We are grateful to the administrative staff of the residential park that provided logistic support for the present study, and to the “Superintendência de Controle de Endemias” of the state of São Paulo (SUCEN) for their valuable help in collecting ticks. This work was supported by the Brazilian funding agencies FAPESP, CNPq, and CAPES

    Cysteine Boosts Fitness Under Hypoxia-Mimicked Conditions in Ovarian Cancer by Metabolic Reprogramming

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    Funding Information: Funding. This research was supported by Funda??o para a Ci?ncia e Tecnologia (FCT) (Ph.D. ProRegeM program, Ref: PD/BD/105893/2014; FCT individual Ph.D. fellowship Ref: 2020.06956.BD) and iNOVA4 Health (Project 4 and Project 21). iNOVA4Health-UID/Multi/04462/2013 is a program financially supported by Funda??o para a Ci?ncia e Tecnologia/ Minist?rio da Educa??o e Ci?ncia, through national funds. The authors would like to acknowledge the Instituto Portugu?s de Oncologia de Lisboa Francisco Gentil (IPOLFG) for partially funding the project. Publisher Copyright: © Copyright © 2021 Nunes, Ramos, Santos, Mendes, Silva, Vicente, Pereira, Félix, Gonçalves and Serpa.Among gynecologic malignancies, ovarian cancer is the third most prevalent and the most common cause of death, especially due to diagnosis at an advanced stage together with resistance to therapy. As a solid tumor grows, cancer cells in the microenvironment are exposed to regions of hypoxia, a selective pressure prompting tumor progression and chemoresistance. We have previously shown that cysteine contributes to the adaptation to this hypoxic microenvironment, but the mechanisms by which cysteine protects ovarian cancer cells from hypoxia-induced death are still to be unveiled. Herein, we hypothesized that cysteine contribution relies on cellular metabolism reprogramming and energy production, being cysteine itself a metabolic source. Our results strongly supported a role of xCT symporter in energy production that requires cysteine metabolism instead of hydrogen sulfide (H2S) per se. Cysteine degradation depends on the action of the H2S-synthesizing enzymes cystathionine β-synthase (CBS), cystathionine γ-lyase (CSE), and/or 3-mercaptopyruvate sulfurtransferase (MpST; together with cysteine aminotransferase, CAT). In normoxia, CBS and CSE inhibition had a mild impact on cysteine-sustained ATP production, pointing out the relevance of CAT + MpST pathway. However, in hypoxia, the concomitant inhibition of CBS and CSE had a stronger impact on ATP synthesis, thus also supporting a role of their hydrogen sulfide and/or cysteine persulfide-synthesizing activity in this stressful condition. However, the relative contributions of each of these enzymes (CBS/CSE/MpST) on cysteine-derived ATP synthesis under hypoxia remains unclear, due to the lack of specific inhibitors. Strikingly, NMR analysis strongly supported a role of cysteine in the whole cellular metabolism rewiring under hypoxia. Additionally, the use of cysteine to supply biosynthesis and bioenergetics was reinforced, bringing cysteine to the plateau of a main carbon sources in cancer. Collectively, this work supports that sulfur and carbon metabolism reprogramming underlies the adaptation to hypoxic microenvironment promoted by cysteine in ovarian cancer.publishersversionpublishe

    Problemas de coordenação motora em crianças de 4 a 8 anos: levantamento baseado no relato de professores

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    The term developmental coordination Disorder (DCD) is still new in Brazil and most of the children with this type of problems are not diagnosed. Motor coordination difficulties usually are observed at school, and although complaints about children with handwriting problems or motor awkwardness are quite common, these difficulties are not identified as a problem that deserves special attention. The objective of this study was to examine the frequency and in which activities do teachers observe motor coordination problems among children ages 4 to 8 years old. A simple questionnaire, with direct questions, was sent to schools of the metropolitan region of Belo Horizonte. Data from 288 questionnaires, 148 from teachers of public schools and 140 from private schools, were analyzed descriptively. The majority of the teachers, 88% from the public schools and 79% from the private ones, reported that they usually observe one or two students with motor coordination problems in each class they teach, which resulted in an overall estimate of 18,6% children with some sort of motor difficulty. This result exceeds the 6% reported in the international literature; therefore, it is important to invest in epidemiological studies and in the correct identification of DCD among the Brazilian children.O termo transtorno do desenvolvimento da coordenação (TDC) ainda é pouco usado no Brasil e a maioria das crianças com esse tipo de problema não é diagnosticada. As dificuldades de coordenação motora geralmente são evidenciadas na escola e, embora queixas de crianças com problemas de escrita ou lentidão motora sejam comuns, essas dificuldades não são identificadas como uma questão que merece atenção especial. O objetivo deste estudo foi examinar a freqüência e as atividades nas quais professores observam dificuldades de coordenação motora em crianças de 4 a 8 anos de idade. Um questionário simples, com questões fechadas, foi enviado a escolas da região metropolitana de Belo Horizonte. Dados de 288 questionários, sendo 148 de professores da rede Municipal e 140 de escolas particulares, foram analisados descritivamente. A maioria dos professores, 88% nas escolas Municipais e 79% nas particulares, indicaram que geralmente observam problemas de coordenação em um a dois alunos em cada classe, o que resultou na estimativa de 18,6% de crianças com algum tipo de dificuldade motora. Estes dados superam os 6% reportados na literatura internacional, sendo importante investir em estudos epidemiológicos e na identificação correta do TDC em crianças brasileiras

    Pathophysiology of major depression by clinical stages

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    The comprehension of the pathophysiology of the major depressive disorder (MDD) is essential to the strengthening of precision psychiatry. In order to determine the relationship between the pathophysiology of the MDD and its clinical progression, analyzed by severity of the depressive symptoms and sleep quality, we conducted a study assessing different peripheral molecular biomarkers, including the levels of plasma C-reactive protein (CRP), serum mature brain-derived neurotrophic factor (mBDNF), serum cortisol (SC), and salivary cortisol awakening response (CAR), of patients with MDD (n = 58) and a control group of healthy volunteers (n = 62). Patients with the first episode of MDD (n = 30) had significantly higher levels of CAR and SC than controls (n = 32) and similar levels of mBDNF of controls. Patients with treatment-resistant depression (TRD, n = 28) presented significantly lower levels of SC and CAR, and higher levels of mBDNF and CRP than controls (n = 30). An increased severity of depressive symptoms and worse sleep quality were correlated with levels low of SC and CAR, and with high levels of mBDNF. These results point out a strong relationship between the stages clinical of MDD and changes in a range of relevant biological markers. This can assist in the development of precision psychiatry and future research on the biological tests for depression

    First report of multiple lineages of dengue viruses type 1 in Rio de Janeiro, Brazil

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    <p>Abstract</p> <p>Background</p> <p>In Brazil dengue has been a major public health problem since DENV-1 introduction and spread in 1986. After a low or silent co-circulation, DENV-1 re-emerged in 2009 causing a major epidemic in the country in 2010 and 2011. In this study, the phylogeny of DENV-1 strains isolated in RJ after its first introduction in 1986 and after its emergence in 2009 and 2010 was performed in order to document possible evolutionary patterns or introductions in a re-emergent virus.</p> <p>Findings</p> <p>The analysis of the E gene sequences demonstrated that DENV-1 isolated during 2009/2010 still belong to genotype V (Americas/Africa) but grouping in a distinct clade (lineage II) of that represented by earlier DENV-1 (lineage I). However, strains isolated in 2011 grouped together forming another distinct clade (lineage III).</p> <p>Conclusions</p> <p>The monitoring of DENV is important to observe the spread of potentially virulent strains as well to evaluate its impact over the population during an outbreak. Whether explosive epidemics reported in Brazil caused mainly by DENV-1 was due to lineage replacement, or due the population susceptibility to this serotype which has not circulated for almost a decade or even due to the occurrence of secondary infections in a hyperendemic country, is not clear. This is the first report of multiple lineages of DENV-1 detected in Brazil.</p
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