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The structure of gentiogenal, (+/-)5-formyl-6-methyl-3,4-dihydro-1H,6H-pyrano-[3,4-c-]-pyran-1-one, a conversion product of the aglucone of gentiopicrin (gentiopicroside), isolated from BLACKSTONIA PERFOLIATA (Gentianaceae), was elucidated by (1)H- and (13)C NMR spectroscopic, mass spectrometric and X-ray diffraction methods. In a TLC bioassay gentiogenal showed fungitoxicity towards PENICILLIUM EXPANSUM.  相似文献   
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IntroductionBipolar disorder (BD) is a prevalent, chronic and progressive illness. There is a growing body of evidence indicating that brain-derived neurotrophic factor (BDNF) plays an important role in the pathophysiology of BD.ObjectiveThe aim of this study was to evaluate BDNF plasma levels in BD patients with long term illness in comparison with controls.Methods87 BD type I patients and 58 controls matched by age, gender and education level were enrolled in this study. All subjects were assessed by the Mini-International Neuropsychiatric Interview and the patients by the Young Mania Rating Scale and the Hamilton Depression Rating Scale. The plasma levels of BDNF were measured by ELISA.ResultsOn average, patients had suffered from BD for 23.4 years. In comparison with controls, BD patients with mania presented a 1.90-fold increase in BDNF plasma levels (p = .001), while BD patients in remission presented a 1.64-fold increase in BDNF plasma levels (p = .03). BDNF plasma levels were not influenced by age, length of illness or current medications.ConclusionsThe present study suggests that long-term BD patients exhibit increased circulating levels of BDNF.  相似文献   
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This study aimed to evaluate the impact of dental caries treatment on oral health‐related quality of life (OHRQoL) among schoolchildren and the responsiveness of the Child Perceptions Questionnaire (CPQ8‐10) instrument. Brazilian schoolchildren, 8–10 yr of age, were randomly selected and assigned to two groups – dental caries treatment (DCT) and caries‐free (CF) – according to their caries experience [decayed, missing, or filled primary teeth (dmft) and decayed, missing or filled secondary teeth (DMFT) values of ≥0]. The CPQ8‐10 instrument was administered at baseline and at 4 wk of follow‐up (i.e. 4 wk after completion of dental treatment). In the DCT group, increases in CPQ8‐10 scores were observed between the baseline and follow‐up results. However, longitudinal evaluation of the CF group demonstrated no statistically significant difference in CPQ8‐10 scores. Responsiveness of the CPQ8‐10 instrument (magnitude of change in CPQ8‐10 scores) in the DCT group was greater (effect size >0.7) than in the CF group. The findings of this study show that dental caries treatment has an important impact on OHRQoL of children. The CPQ8‐10 was considered an acceptable instrument for longitudinal measurement of changes in OHRQoL.  相似文献   
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We evaluated the possible mechanisms underlying the oxidative stress induced by ethanol withdrawal. With this purpose, we verified the role of AT1 receptors in such response. Male Wistar rats were treated with ethanol 3%–9% (vol./vol.) for 21 days. Ethanol withdrawal was induced by abrupt discontinuation of the treatment. Experiments were performed 48 hours after ethanol discontinuation. Increased plasma levels of angiotensin II were detected after ethanol withdrawal. Losartan (10 mg/kg; p.o. gavage), a selective AT1 receptor antagonist, impeded the increase in blood pressure induced by ethanol withdrawal. Increased lipoperoxidation and superoxide anion (O2?) levels were detected in aortas after ethanol withdrawal, and losartan prevented these responses. Decreased hydrogen peroxide and nitrate/nitrite concentration were detected in aortas after ethanol withdrawal, and losartan prevented these effects. Nitrotyrosine immunostaining in the rat aorta was increased after ethanol withdrawal, and AT1 blockade impeded this response. Increased expression of PKCδ and p47phox was detected after ethanol withdrawal, and treatment with losartan prevented these responses. Our study provides novel evidence that ethanol withdrawal increases vascular oxidative stress and blood pressure through AT1-dependent mechanisms. These findings highlight the importance of angiotensin II in ethanol withdrawal–induced increase in blood pressure and vascular oxidative damage.  相似文献   
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A widespread epidemic of Zika virus (ZIKV) infection was reported in 2015 in South and Central America, with neurological symptons including meningoencephalitis and Guillain-Barré syndrome in adults, besides an apparent increased incidence of microcephaly in infants born to infected mothers. It is becoming a necessity to have a trustworthy animal model to better understand ZIKV infection. In this study we used newborn white Swiss mice as a model to investigate the ZIKV strain recently isolated in Brazil. ZIKV was inoculated via intracerebral and subcutaneous routes and analysed through gross histopathology and immunohistochemistry. Here we demonstrated first that the intracerebral group (ICG) displayed severe cerebral lesions, with neuronal death, presence of apoptotic bodies, white matter degeneration and neutrophil perivascular cuffing. In the subcutaneous group (SCG), we observed moderate cerebral lesions, morphologically similar to that found in ICG and additional myelopathy, with architectural loss, marked by neuronal death and apoptotic bodies. Interestingly, we found an intense astrogliosis in brain of both groups, with increased immunoexpression of GFAP (glial fibrillary acidic protein) and presence of hypertrophic astrocytes. The spinal cord of subcutaneous group (SCG) exhibited reduction of astrocytes, but those positive for GFAP were hypertrophic and presented prolonged cellular processes. Finally significant lesions in the central nervous system (CNS) were present in newborn mice inoculated by both routes, but SCG method led to an important neurological manifestations (including myelopathy), during a longer period of time and appears for us to be a better model for ZIKV infection.  相似文献   
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