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Type 2 diabetes (T2DM) is among the most prevalent metabolic diseases in the world and may result in several long‐term complications. The crosstalk between gut microbiota and host metabolism is closely related to T2DM. Currently, fragmented data hamper defining the relationship between probiotics and T2DM. This systematic review aimed at investigating the effects of probiotics on T2DM in animal models. We systematically reviewed preclinical evidences using PubMed/MEDLINE and Scopus databases, recovering 24 original articles published until September 27th, 2019. This systematic review was performed according to PRISMA guidelines. We included experimental studies with animal models reporting the effects of probiotics on T2DM. Studies were sorted by characteristics of publications, animal models, performed analyses, probiotic used and interventions. Bias analysis and methodological quality assessments were examined through the SYRCLE's Risk of Bias tool. Probiotics improved T2DM in 96% of the studies. Most studies (96%) used Lactobacillus strains, and all of them led to improved glycaemia. All studies used rodents as models, and male animals were preferred over females. Results suggest that probiotics have a beneficial effect in T2DM animals and could be used as a supporting alternative in the disease treatment. Considering a detailed evaluation of the reporting and methodological quality, the current preclinical evidence is at high risk of bias. We hope that our critical analysis will be useful in mitigating the sources of bias in further studies.  相似文献   
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Black flies (Simuliidae) are considered to be pests in rural and in some urban areas in the south of Brazil due to the bites of females. Little information exists on the factors that contribute to Simuliidae distribution in these areas. We sampled 39 streams in the state of Rio Grande do Sul in September 2004 to address ecological aspects. Of the 18 species collected, those that occurred in more than 50% of the streams were: Simulium subnigrum Lutz 1910, Simulium pertinax Kollar 1882, Simulium subpallidum Lutz 1910 and Simulium incrustatum Lutz 1910. Species richness was not influenced by any of the environmental or geographical variables considered, and there was no pattern of species co-occurrence, corroborating the hypothesis of a stochastic distribution of the Simuliidae assemblage. When analyzed individually, only three of seven species with occurrence frequency >30% were related to any of the variables measured. The probabilities of occurrence of Simulium jujuyense Paterson & Shannon 1927 and S. pertinax were higher in streams with high values of water pH and electrical conductivity, whereas the opposite was observed for S. incrustatum. Therefore, due to stochastic distribution, the population studies of Simuliidae are more suitable for predicting the occurrence of species in rural areas than are studies of assemblages.  相似文献   
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AIM:To investigate the geographic distributions and time trends of gastric cancer(GC)incidence and mortality in Brazil.METHODS:An ecological study of the DATASUS registry was conducted by identifying hospitalizations for GC between January 2005 and December 2010.The data included information on the gender,age,and town of residence at the time of hospital admission and death.RESULTS:The GC rates,adjusted according to available hospital beds,decreased from 13.8 per 100000in 2005 to 12.7 per 100000 in 2010.The GC rates decreased more among the younger age groups,in which the male-to-female difference also decreased in comparison to the older age groups.Although the lethality rates tended to increase with age,young patients were proportionally more affected.The spatial GC distribution showed that the rates were higher in the south and southeast.However,while the rates decreased in the central-west and south,they increased in the northern regions.A geographic analysis showed higher rates of GC in more urbanized areas,with a coast-toinland gradient.Geographically,GC lethality overlapped greatly with the hospital admission rates.CONCLUSION:The results of this study support the hypothesis of a critical role for environmental factors in GC pathogenesis.The declining rates in young patients,particularly males,suggest a relatively recent decrease in the exposure to risk factors associated with GC.The spatial distribution of GC indicates an ongoing dynamic change within the Brazilian environment.  相似文献   
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The aim of this study was to analyse mastication and the sense of taste in 39 patients submitted to cancer treatment in different areas of the body and to compare these variables with those of 44 control individuals within the same age range. The following aspects were assessed: dental status (DMFT); stimulated and non‐stimulated salivary flow; sense of taste (salty, sweet, bitter and sour); and masticatory performance (MP), through the calculation of X50. Logistic regression models were established to test the association between the independent variables and cancer treatment. Cancer patients had lesser stimulated salivary flow, a smaller number of teeth and occlusal units, worse MP, higher salty, sweet and sour taste scores and a lower bitter taste score (P < 0·05). A significant positive correlation was found between MP and the DMFT index in both groups (P < 0·05), meaning that a lower DMFT index value denoted a smaller X50 value (better masticatory performance). The logistic regression model revealed that patients who had undergone cancer treatment had a greater probability of exhibiting a smaller number of teeth, higher salty and smaller bitter taste scores (P < 0·05). It was concluded that patients who were submitted to cancer treatment presented oral physiology alterations when compared with control subjects at the same age range.  相似文献   
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