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991.
Objective: The objective of this study was to evaluate daily physical activity (DPA) in asthmatic children with different levels of disease severity, but with good asthma control, relative to a control group. Methods: This was a cross-sectional study in which a total of 121 children between the ages of 7 and 12 years old were evaluated; 72 were asthmatic children (32 mild, 24 moderate and 23 severe), and 42 children were not asthmatics. The asthmatic children studied had been in medical treatment for at least 6 months and experienced no change in symptoms during the 4 weeks prior to the study. The DPA was monitored over 6 days (4 weekdays and 2 weekend days). Motor activity was recorded with an accelerometer that measured the total number of steps (TNS), the number of steps in moderate physical activity (NS-MPA) and the duration, in minutes, of physical activity performed at moderate intensity. Results: There were no differences among the TNS performed by children with mild, moderate or severe persistent asthma and the control group (14?410?±?4379, 14?710?±?4892, 13?838?±?3341 and 12?968?±?3682 steps, respectively). The NS-MPA was also similar among all of the groups (6589?±?2065, 6605?±?2324, 6223?±?1689 and 5990?±?1840 steps, respectively). Sedentary asthmatic children were overweight more often than asthmatic children who were physically active, although lung function was not different between these groups. Conclusion: Children with good asthma control, independent of disease severity, had DPA levels similar to children without asthma. However, more asthmatic children were overweight if sedentary as compared to physically active asthmatic children.  相似文献   
992.
In vitro effect of the association of the entomopathogenic nematodes Heterorhabditis bacteriophora HP88 and Heterorhabditis indica LPP1 with the essential oil of Lippia sidoides on engorged females of Rhipicephalus microplus was assessed. Engorged females with homogeneous weights (p?>?0.05) were divided into six groups of ten ticks each (each female = an experimental unit). In the treated groups, the ticks were exposed to the oil (40 μl/ml?=?4 %) and nematodes (300 entomopathogenic nematodes (EPNs/tick) separately and also to the nematodes together with the oil, while in the control group, the females were immersed in Tween 80 (3 %). All the treatments caused a significant reduction in the egg mass weight (p?<?0.05). The hatching percentage of larvae was reduced (p?<?0.05) in the groups treated with H. bacteriophora HP88, H. indica LPP1, and H. bacteriophora HP88 associated with the oil, but in the group treated only with the oil, the hatching of percentage of larvae rate was similar to that of the control group (p?>?0.05). The percentage of control in the group exposed only to the oil was 50.7 %, while in the other treated groups, the percentage of control was greater than 95 %, reaching 100 % in the group treated with H. indica LPP1 associated with the oil. The results of the L. sidoides essential oil in the concentrations tested in association with both H. bacteriophora HP88 and H. indica LPP1 indicate that these combinations can be used to control R. microplus.  相似文献   
993.
The objective of this study was to evaluate the quality of bovine frozen-thawed sperm cells after Percoll gradient centrifugation. Frozen semen doses were obtained from six bulls of different breeds, including three taurine and three Zebu animals. Four ejaculates per bull were evaluated before and after discontinuous Percoll gradient centrifugation. Sperm motility was assessed by computer-assisted semen analysis and the integrity of the plasma and acrosomal membranes, as well as mitochondrial function, were evaluated using a combination of fluorescent probes propidium iodide, fluorescein isothiocyanate-conjugated Pisum sativum agglutinin and 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolcarbocyanine iodide. The procedure of Percoll gradient centrifugation increased the percentage of total and progressive sperm motility, beat frequency, rectilinear motility, linearity and rapidly moving cells. In addition, the percentage of cells with intact plasma membrane and mitochondrial membrane potential was increased in post-centrifugation samples. However, the percentage of sperm cells with intact acrosomal membrane was markedly reduced. The method used selected the motile cells with intact plasma membrane and higher mitochondrial functionality in frozen-thawed bull semen, but processing, centrifugation and/or the Percoll medium caused damage to the acrosomal membrane.  相似文献   
994.
This study aimed to determine the prevalence of overweight and associated risk factors in children and adolescents in Pernambuco State, Brazil, in 2006. The cross-sectional, population-based study included 1,435 individuals from 5 to 19 years of age. Poisson regression was used to evaluate the association between selected variables and overweight. Prevalence was 13.3% for overweight (95%CI: 11.6-15.1) and 3.8% for obesity. Adjusted prevalence ratios showed that higher family income, maternal schooling, possession of household consumer goods, living in urban areas, and maternal overweight were associated with overweight in children and adolescents. The high prevalence of overweight in Pernambuco emphasizes the need for public health measures targeting all families regardless of socioeconomic status.  相似文献   
995.
996.
997.
Dengue is a mosquito-borne disease that affects millions of people worldwide yearly. Currently, there is no vaccine or specific treatment available. Further investigation on dengue pathogenesis is required to better understand the disease and to identify potential therapeutic targets. The chemokine system has been implicated in dengue pathogenesis, although the specific role of chemokines and their receptors remains elusive. Here we describe the role of the CC-chemokine receptor CCR5 in Dengue virus (DENV-2) infection. In vitro experiments showed that CCR5 is a host factor required for DENV-2 replication in human and mouse macrophages. DENV-2 infection induces the expression of CCR5 ligands. Incubation with an antagonist prevents CCR5 activation and reduces DENV-2 positive-stranded (+) RNA inside macrophages. Using an immunocompetent mouse model of DENV-2 infection we found that CCR5−/− mice were resistant to lethal infection, presenting at least 100-fold reduction of viral load in target organs and significant reduction in disease severity. This phenotype was reproduced in wild-type mice treated with CCR5-blocking compounds. Therefore, CCR5 is a host factor required for DENV-2 replication and disease development. Targeting CCR5 might represent a therapeutic strategy for dengue fever. These data bring new insights on the association between viral infections and the chemokine receptor CCR5.  相似文献   
998.
BACKGROUND: Presinusoidal portal hypertension with frequent episodes of upper gastrointestinal variceal bleeding are hallmarks of hepatosplenic Mansons schistosomiasis; a clinical form that affects about 5% of Brazilians who are infected by Schistosoma mansoni. AIMS: To evaluate duplex sonography findings in patients with hepatosplenic Mansons schistosomiasis with and without upper gastrointestinal variceal hemorrhage. METHODS: A cross-sectional study was performed whereby 27 consecutive patients with hepatosplenic Mansons schistosomiasis were divided into two groups: group I (six men and six women; mean age 48.7 years) with a past history of bleeding and group II (four men and eight women; mean age 44.7 years) without a past history of upper gastrointestinal bleeding, underwent duplex sonography examination. All patients underwent the same upper gastrointestinal endoscopy and laboratory examinations. Those with signs of mixed chronic liver disease or portal vein thrombosis (three cases) were excluded. RESULTS: Group I showed significantly higher mean portal vein flow velocity than group II (26.36 cm/s vs 17.15 cm/sec). Although, as a whole it was not significant in all forms of collateral vessels (83% vs 100%), there was a significantly higher frequency of splenorenal collateral circulation type in group II compared with group I (17% vs 67%). The congestion index of the portal vein was significantly lower in group I than in group II (0.057 cm vs 0.073 cm/sec). CONCLUSION: Our duplex sonography findings in hepatosplenic Mansons schistosomiasis support the idea that schistosomotic portal hypertension is strongly influenced by overflow status, and that collateral circulation seems to play an important role in hemodynamic behavior.  相似文献   
999.
1000.
Enzymes of the OXA-48 family have become some of the most important beta-lactamases in the world. A new OXA-48 variant (OXA-370) was first described for an Enterobacter hormaechei strain isolated in Rio Grande do Sul (southern region of Brazil) in 2013. Here we report detection of the blaOXA-370 gene in 24 isolates belonging to three Enterobacteriaceae species (22 Klebsiella pneumoniae isolates, 1 Enterobacter cloacae isolate, and 1 Enterobacter aerogenes isolate) collected from five hospitals in Rio de Janeiro, Brazil, in 2013 and 2014. The isolates showed a multidrug resistance profile, and 12.5% were resistant to polymyxin B. Besides blaOXA-370, no other carbapenemase genes were observed by PCR, whereas blaOXA-1 was found in all isolates and 22 isolates (91.6%) possessed blaCTX-M-15. Molecular typing of the K. pneumoniae isolates by pulsed-field gel electrophoresis (PFGE) showed the presence of two clonal groups, i.e., KpA (21 isolates) and KpB (1 isolate). KpA was characterized as sequence type 16 (ST16) and KpB as ST1041 by multilocus sequence typing (MLST). ST16 has been observed for KPC-producing K. pneumoniae in Rio de Janeiro. Plasmid analysis performed with six representative OXA-370-producing isolates showed plasmids harboring the blaOXA-370 gene in all strains, ranging from 25 kb to 150 kb. This study suggests that there is an urgent need to investigate the presence of OXA-370 and dissemination of the K. pneumoniae ST16 clone carrying this gene in Brazil.  相似文献   
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