199 research outputs found

    Potent hepatoprotective effect in CCl4-induced hepatic injury in mice of phloroacetophenone from Myrcia multiflora

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    Background: This study investigated the hepatoprotective effect and antioxidant properties of phloroacetophenone (2',4',6'-trihydroxyacetophenone - THA), an acetophenone derived from the plant Myrcia multiflora. Material & Method: The free radical scavenging activity in vitro and induction of oxidative hepatic damage by carbon tetrachloride (CCl4) (0.5 ml/kg, i.p.) were tested in male Swiss mice (2595 g). Results: This compound exhibited in vitro antioxidant effects on FeCl2-ascorbate-induced lipid peroxidation (LPO) in mouse liver homogenate, scavenging hydroxyl and superoxide radicals, and 2,2-diphenyl-1-picrylhydrazyl. The in vivo assays showed that THA significantly (p<0.01) prevented the increases of hepatic LPO as measured by the levels of thiobarbituric acid-reactive substances, mitochondrial swelling. It also protected hepatocytes against protein carbonylation and oxidative DNA damage. Consistent with these observations, THA pre-treatment normalized the activities of antioxidant enzymes, such as catalase, glutathione peroxidase, and superoxide dismutase, and increased the levels of reduced glutathione (GSH) in CCl4-treated mice. In addition, THA treatment significantly prevented the elevation of serum enzymatic activities of alanine amino transferase, aspartate amino transferase, and lactate dehydrogenase, as well as histological alterations induced by CCl4. Silymarin (SIL) (24 mg/kg), a known hepatoprotective drug used for comparison, led to a significant decrease (p<0.01) in activities of theses enzymes in way very similar to that observed in pre-treatment with THA. Conclusion: These results suggest that the protective effects are due to reduction of oxidative damage induced by CCl4 resulting from the antioxidant properties of THA.Keywords: antioxidant; hepatoprotective; 2',4',6'-trihydroxyacetophenone; Myrcia multiflora; CCl4; Silymari

    Brazilian Bidens pilosa LinneÂŽ yields fraction containing quercetin-derived flavonoid with free radical scavenger activity and hepatoprotective effects

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    Bidens pilosa is a plant used by Amazonian and Asian folks for some hepatopathies. The hydroethanol crude extract and three fractions were assessed for antioxidant and hepatoprotective effects. Higher levels of scavenger activity on the 1,1-diphenyl-2-picrylhydrazyl radical, inhibition of deoxyribose oxidation and lipid peroxidation in vitro were detected for the ethyl acetate fraction (IC50∼4.3-32.3 mg/ml) followed by the crude extract (IC50∼14.2-98.0 mg/ml). The ethyl acetate fraction, again followed by the crude extract, showed high contents of total soluble polyphenols (3.6±0.2 and 2.1±0.2 GAE/mg, respectively) and presence of a quercetin-derived flavonoid identified as quercetin 3,3′-dimethyl ether 7-Ο-β-D-glycopyranoside. Both products were assayed for hepatoprotector effects against CCl4-induced liver injury in mice. Markers of oxidative stress and hepatic injury were evaluated. The results showed that the 10-day pretreatments (15 mg/kg, p.o.) protected the livers against injury by blocking CCl4-induced lipid peroxidation and protein carbonylation and the DNA fragmentation was decreased (∼60%). The pretreatments avoided the loss of the plasma ferric reducing/antioxidant power and the elevation of serum transaminases and lactate dehydrogenase activities. The results suggest that the main constituents responsible for the hepatoprotective effects with free radical scavenger power associated are well extracted by performing fractionation with ethyl acetate. The findings support the Brazilian traditional use of this plant and justify further evaluations for the therapeutic efficacy and safety of the constituents of the ethyl acetate fraction to treat some liver diseases.Keywords: Bidens pilosa L.; hydroethanol maceration; ethyl acetate fractionation; free radical scavenger; hepatoprotection; CCl4 toxicit

    Influence of Apolipoprotein E Plasma Levels and Tobacco Smoking on the Induction of Neutralising Antibodies to Interferon-Beta

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    Interferon-beta (IFN-beta) therapy for multiple sclerosis (MS) is associated with a potential for induction of neutralizing antibodies (NAbs). Because immune reactivity depends on changes in lipoprotein metabolism, we investigated whether plasma lipoprotein profiles could be associated with the development of NAbs. Thirty-one female MS patients treated with subcutaneously administered IFN-beta were included. Demographic and clinical characteristics were compared between NAbs response groups using t tests for continuous and logistic regression analysis and Fisher's exact tests for categorical data, respectively. Multivariate logistic regression was used to evaluate the effect of potential confounders. Patients who developed NAbs had lower apoE levels before treatment, 67 (47-74) mg/L median (interquartile range), and at the moment of NAb analysis, 53 (50-84) mg/L, in comparison to those who remained NAb-negative, 83 (68-107) mg/L, P = 0.03, and 76 (66-87) mg/L, P = 0.04, respectively. When adjusting for age and smoking for a one-standard deviation decrease in apoE levels, a 5.6-fold increase in the odds of becoming NAb-positive was detected: odds ratios (OR) 0.18 (95% CI 0.04-0.77), P = 0.04. When adjusting for apoE, smoking habit became associated with NAb induction: OR 5.6 (95% CI 1.3-87), P = 0.03. These results suggest that apoE-containing lipoprotein metabolism and, possibly, tobacco smoking may be associated with risk of NAb production in female MS patients treated with IFN-beta

    Portuguese-Brazilian Evidence-Based Guideline on the Management of Hyperglycemia in Type 2 Diabetes Mellitus

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    Background: In current management of type 2 diabetes (T2DM), cardiovascular and renal prevention have become important targets to be achieved. In this context, a joint panel of four endocrinology societies from Brazil and Portugal was established to develop an evidence-based guideline for treatment of hyperglycemia in T2DM. Methods: MEDLINE (via PubMed) was searched for randomized clinical trials, meta-analyses, and observational studies related to diabetes treatment. When there was insufficient high-quality evidence, expert opinion was sought. Updated positions on treatment of T2DM patients with heart failure (HF), atherosclerotic CV disease (ASCVD), chronic kidney disease (CKD), and patients with no vascular complications were developed. The degree of recommendation and the level of evidence were determined using predefined criteria. Results and conclusions: In non-pregnant adults, the recommended HbA1c target is below 7%. Higher levels are recommended in frail older adults and patients at higher risk of hypoglycemia. Lifestyle modification is recommended at all phases of treatment. Metformin is the first choice when HbA1c is 6.5-7.5%. When HbA1c is 7.5-9.0%, dual therapy with metformin plus an SGLT2i and/or GLP-1RA (first-line antidiabetic agents, AD1) is recommended due to cardiovascular and renal benefits. If an AD1 is unaffordable, other antidiabetic drugs (AD) may be used. Triple or quadruple therapy should be considered when HbA1c remains above target. In patients with clinical or subclinical atherosclerosis, the combination of one AD1 plus metformin is the recommended first-line therapy to reduce cardiovascular events and improve blood glucose control. In stable heart failure with low ejection fraction ( 30 mL/min/1.73 m2, metformin plus an SGLT-2i is recommended to reduce cardiovascular mortality and heart failure hospitalizations and improve blood glucose control. In patients with diabetes-associated chronic kidney disease (CKD) (eGFR 30-60 mL/min/1.73 m2 or eGFR 30-90 mL/min/1.73 m2 with albuminuria > 30 mg/g), the combination of metformin and an SGLT2i is recommended to attenuate loss of renal function, reduce albuminuria and improve blood glucose control. In patients with severe renal failure, insulin-based therapy is recommended to improve blood glucose control. Alternatively, GLP-1RA, DPP4i, gliclazide MR and pioglitazone may be considered to reduce albuminuria. In conclusion, the current evidence supports individualizing anti-hyperglycemic treatment for T2DM.info:eu-repo/semantics/publishedVersio

    PrevalĂȘncia e fatores associados aos comportamentos sedentĂĄrios em adolescentes

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    OBJETIVO Analisar a prevalĂȘncia e fatores associados aos comportamentos sedentĂĄrios em adolescentes. MÉTODOS Estudo transversal com adolescentes de 10 a 17 anos de idade, de ambos os sexos, pertencentes a uma coorte de nascimentos entre 1994-1999 na cidade de CuiabĂĄ, Mato Grosso, Brasil. Para o levantamento dos dados, foi utilizado um questionĂĄrio contendo informaçÔes sociodemogrĂĄficas, econĂŽmicas e de estilo de vida e aferição de dados antropomĂ©tricos. Determinou-se como comportamento sedentĂĄrio o uso de televisĂŁo e/ou computador/vĂ­deo games por um tempo igual ou superior a 4 horas/dia. Avaliou-se a associação de comportamentos sedentĂĄrios com o Ă­ndice de massa corporal, tanto na infĂąncia quanto na adolescĂȘncia, e com variĂĄveis sociodemogrĂĄficas e comportamentais por meio de regressĂŁo logĂ­stica hierarquizada. RESULTADOS A prevalĂȘncia global de comportamentos sedentĂĄrios foi de 58,1%. Dos 1.716 adolescentes estudados, 50,7% (n = 870) eram do sexo masculino. Na anĂĄlise multivariada, apĂłs ajuste para fatores de confusĂŁo, as variĂĄveis que permaneceram associadas com os comportamentos sedentĂĄrios foram: idade (14 anos ou mais) (OR = 3,51; IC95% 2,19;5,60); classe econĂŽmica elevada (OR = 3,83; IC95% 2,10;7,01); maior nĂ­vel de escolaridade da mĂŁe (OR = 1,81; IC95% 1,09;3,01); residir no interior (OR = 0,49; IC95% 0,30;0,81); atividade fĂ­sica insuficiente (OR = 1,25; IC95% 1,02;1,53); experimentação de bebidas alcoĂłlicas (OR = 1,34; IC95% 1,08;1,66) e excesso de peso na adolescĂȘncia (OR = 1,33; IC95% 1,06;1,68). CONCLUSÕES A elevada proporção de adolescentes em atividades sedentĂĄrias e a nĂŁo associação dessas atividades na adolescĂȘncia com o excesso de peso na infĂąncia indicam a necessidade de intervençÔes para redução de vĂĄrios comportamentos de risco. O incentivo Ă  prĂĄtica de atividade fĂ­sica como forma de reduzir os comportamentos sedentĂĄrios e consequentemente o excesso de peso entre os jovens torna-se fundamental

    Effective Rheology of Bubbles Moving in a Capillary Tube

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    We calculate the average volumetric flux versus pressure drop of bubbles moving in a single capillary tube with varying diameter, finding a square-root relation from mapping the flow equations onto that of a driven overdamped pendulum. The calculation is based on a derivation of the equation of motion of a bubble train from considering the capillary forces and the entropy production associated with the viscous flow. We also calculate the configurational probability of the positions of the bubbles.Comment: 4 pages, 1 figur

    Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

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    The inclusive and dijet production cross-sections have been measured for jets containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The measurements use data corresponding to an integrated luminosity of 34 pb^-1. The b-jets are identified using either a lifetime-based method, where secondary decay vertices of b-hadrons in jets are reconstructed using information from the tracking detectors, or a muon-based method where the presence of a muon is used to identify semileptonic decays of b-hadrons inside jets. The inclusive b-jet cross-section is measured as a function of transverse momentum in the range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet cross-section is measured as a function of the dijet invariant mass in the range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets and the angular variable chi in two dijet mass regions. The results are compared with next-to-leading-order QCD predictions. Good agreement is observed between the measured cross-sections and the predictions obtained using POWHEG + Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet cross-section. However, it does not reproduce the measured inclusive cross-section well, particularly for central b-jets with large transverse momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final version published in European Physical Journal
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