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41.
This study investigated whether long-term feeding a high-fat diet (HFC) has an effect on schistosomiasis mansoni outcome compared to standard chow diet (SC). Swiss Webster female mice (3 wk old) fed each diet over 5 months, and then were infected with 50 Schistosoma mansoni cercariae. Their nutritional status was assessed by monitoring growth rates twice a week and measuring serum levels of lipoproteins. Mice were euthanised 63 days after infection. Parasitological and liver histological analyses were performed. The levels of TC, HDL-C and LDL-C, fecal and tissue schistosome eggs were statistically different (p<0.05) between groups. Livers from HFC mice showed exudative, exudative/exudative-productive, exudative-productive and productive granulomas, some degree of hepatic steatosis and focal necrosis. Mice fed normal-chow did not present productive granulomas and hepatic steatosis. The morphometric evaluation of hepatic granulomas did not reach statistical significance (p>0.05) between diets assayed. The high-fat diet for long-term produces effects on schistosomiasis mansoni outcome.  相似文献   
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Objective: To evaluate time trends of obesity, abdominal obesity, and cardiovascular risk factors (CRFs) according to BMI and waist circumference (WC) categories in a Mediterranean population. Research Methods and Procedures: Subjects were Spanish men (n = 2383) and women (n = 2525) 25 to 74 years old, examined in 1994 to 1995 and 1999 to 2000 in two independent population‐based cross‐sectional surveys in the northeast of Spain. Lifestyle measures, CRFs, and anthropometric variables were analyzed. Results: Over the 5 years of the study, mean age‐standardized BMI increased by 1.0 units in men and by 0.8 units in women. At the same time the prevalence of obesity increased from 15.4% to 21.9% in men and from 15.4% to 21.4% in women. An upward trend was observed for WC and abdominal obesity (WC > 102 cm in men and WC > 88 cm in women) only in men. The proportion of men and women with hypercholesterolemia, diabetes, and low high‐density lipoprotein‐cholesterol plasma concentration remained stable within BMI and WC categories. The proportion of hypertension and smoking in obese men significantly increased from 1995 to 2000. Discussion: The 5‐year increase in BMI and WC is of considerable magnitude in the present population, although several CRFs remained stable within BMI and WC categories.  相似文献   
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Plant Cell, Tissue and Organ Culture (PCTOC) - Pyrostegia venusta (Ker Gawl.) Miers is a plant used for the treatment of respiratory diseases, diarrhea, vitiligo, jaundice and to attenuate...  相似文献   
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The chirality of the title heterocycles is discussed considering their genesis by desymmetrization of the corresponding adamantanes. Some rules for the specification of the absolute configurations of the enantiomers (R or S) for this type of compounds are proposed. © 1996 Wiley-Liss, Inc.  相似文献   
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Peptic-tryptic digests of alcohol-soluble proteins from flours of 10 accessions of Triticum monococcum with contrasting storage protein compositions and bread-making characteristics were found unable to agglutinate K562(S) cells even at a peptide concentration as high as 14 g/L, agglutination being strongly correlated with toxicity in celiac disease. When fractionated by affinity chromatography on Sepharose-6B coupled with mannan, peptic-tryptic digests separated into three fractions. Fraction C peptides were shown to agglutinate K562(S) cells, whereas peptides in fractions A and B and in the mixed fraction B + C were inactive, suggesting that fraction B contains “protective” peptides that interfere with toxic peptides in fraction C in their agglutinating activity. These results offer an opportunity to study the biochemical and genetic bases of wheat toxicity at the diploid level. Moreover, the reduced toxicity, if any, of Triticum monococcum in the celiac disease, along with the good grain characteristics of some “monococcum” accessions, greatly increases the economical prospects of this wheat species. © 1997 John Wiley & Sons, Inc. J Biochem Toxicol 11: 313–318, 1997.  相似文献   
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Within primates, the great apes are outliers both in terms of body size and lifespan, since they include the largest and longest-lived species in the order. Yet, the molecular bases underlying such features are poorly understood. Here, we leveraged an integrated approach to investigate multiple sources of molecular variation across primates, focusing on over 10,000 genes, including approximately 1,500 previously associated with lifespan, and additional approximately 9,000 for which an association with longevity has never been suggested. We analyzed dN/dS rates, positive selection, gene expression (RNA-seq), and gene regulation (ChIP-seq). By analyzing the correlation between dN/dS, maximum lifespan, and body mass, we identified 276 genes whose rate of evolution positively correlates with maximum lifespan in primates. Further, we identified five genes, important for tumor suppression, adaptive immunity, metastasis, and inflammation, under positive selection exclusively in the great ape lineage. RNA-seq data, generated from the liver of six species representing all the primate lineages, revealed that 8% of approximately 1,500 genes previously associated with longevity are differentially expressed in apes relative to other primates. Importantly, by integrating RNA-seq with ChIP-seq for H3K27ac (which marks active enhancers), we show that the differentially expressed longevity genes are significantly more likely than expected to be located near a novel “ape-specific” enhancer. Moreover, these particular ape-specific enhancers are enriched for young transposable elements, and specifically SINE–Vntr–Alus. In summary, we demonstrate that multiple evolutionary forces have contributed to the evolution of lifespan and body size in primates.  相似文献   
49.
The COVID-19 pandemic led to the reorganization of health care in several countries, including Brazil. Inborn Errors of Metabolism (IEM) are a group of rare and difficult to diagnose genetic diseases caused by pathogenic variants in genes that code for enzymes, cofactors, or structural proteins affecting different metabolic pathways. The aim of this study was to evaluate how COVID-19 affected the diagnosis of patients with IEM during the first year of the pandemic in Brazil comparing two distinct periods: from March 1st, 2019 to February 29th, 2020 (TIME A) and from March 1st, 2020 to February 28th, 2021 (TIME B), by the analysis of the number of tests and diagnoses performed in a Reference Center in South of Brazil. In the comparison TIME A with TIME B, we observe a reduction in the total number of tests performed (46%) and in the number of diagnoses (34%). In both periods analyzed, mucopolysaccharidoses (all subtypes combined) was the most frequent LD suspected and/or confirmed. Our data indicates a large reduction in the number of tests requested for the investigation of IEM and consequently a large reduction in the number of diagnoses caused by the COVID-19 pandemic leading to a significant underdiagnosis of IEM.  相似文献   
50.
Rocky outcrops usually have a peculiar vegetation which differs from that of the surrounding vegetation matrix. In Brazil, a savanna type (cerrado rupestre) is particularly characterized by rocky outcrops and is one of eleven vegetation types which occur throughout Cerrado biome. It has been scarcely studied in detail. Therefore, the aim of this study was to investigate the phytogeographical patterns of the woody species in ten areas of the rocky outcrop savanna in the Brazilian Central Plateau. The difference in spatial distribution of the species was assessed through indicator species and CCA ordination analyses. Ten indicator species showed significantly different distribution. The first axis of the ordination showed association with the edaphic gradient, based on maximum temperature, pH and physical properties of the soils (eigenvalue 0.63). The second axis showed an eigenvalue 0.46, associated with poor rainfall and land declivity. It appears that the woody flora of the rocky outcrop savanna areas of the Brazilian Central Plateau is relatively homogeneous, with low β diversity. Apparently, the size of the woody species populations is what distinguishes the ten investigated areas. Therefore, initiatives and actions for the Cerrado biome conservation must consider not only the size of the protected areas but also that of the populations to be protected, especially the woody species on rocky outcrops.  相似文献   
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