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排序方式: 共有569条查询结果,搜索用时 125 毫秒
121.
Melina Messaoudi Milen Milenkov Werner C. Albrich Mark P. G. van der Linden Thomas Bénet Monidarin Chou Mariam Sylla Patricia Barreto Costa Nathalie Richard Keith P. Klugman Hubert P. Endtz Gláucia Paranhos-Baccalà Jean-No?l Telles 《PloS one》2016,11(3)
For epidemiological and surveillance purposes, it is relevant to monitor the distribution and dynamics of Streptococcus pneumoniae serotypes. Conventional serotyping methods do not provide rapid or quantitative information on serotype loads. Quantitative serotyping may enable prediction of the invasiveness of a specific serotype compared to other serotypes carried. Here, we describe a novel, rapid multiplex real-time PCR assay for identification and quantification of the 40 most prevalent pneumococcal serotypes and the assay impacts in pneumonia specimens from emerging and developing countries. Eleven multiplex PCR to detect 40 serotypes or serogroups were optimized. Quantification was enabled by reference to standard dilutions of known bacterial load. Performance of the assay was evaluated to specifically type and quantify S. pneumoniae in nasopharyngeal and blood samples from adult and pediatric patients hospitalized with pneumonia (n = 664) from five different countries. Serogroup 6 was widely represented in nasopharyngeal specimens from all five cohorts. The most frequent serotypes in the French, South African, and Brazilian cohorts were 1 and 7A/F, 3 and 19F, and 14, respectively. When both samples were available, the serotype in blood was always present as carriage with other serotypes in the nasopharynx. Moreover, the ability of a serotype to invade the bloodstream may be linked to its nasopharyngeal load. The mean nasopharyngeal concentration of the serotypes that moved to the blood was 3 log-fold higher than the ones only found in the nasopharynx. This novel, rapid, quantitative assay may potentially predict some of the S. pneumoniae serotypes invasiveness and assessment of pneumococcal serotype distribution. 相似文献
122.
Vitor Barreto Paravidino Mauro Felippe Felix Mediano Daniel J. Hoffman Rosely Sichieri 《PloS one》2016,11(1)
Objective
Evaluate the effect of different exercise intensities on spontaneous physical activity energy expenditure in overweight adolescents.Methods
A crossover study was developed with a control session, followed by moderate and vigorous exercise sessions, with six days of monitoring each. Twenty-four adolescents, 11–13 years old, male and overweight were selected. Spontaneous physical activity energy expenditure was assessed by accelerometers. Linear mixed effects models were used to evaluate the differences per session across time.Results
Energy expenditure during the 1st hour was different between all three sessions, with averages of 82, 286 and 343 kcal to the control, moderate and vigorous sessions, respectively (p <0.001). The same pattern of difference in energy expenditure between the sessions remained after 24 hours (704 vs 970 vs 1056 kcal, p <0.001). However, energy expenditure during the six days indicates compensation from second to the sixth day, although small differences remained at the end of the 6-day period (5102 vs 5193 vs 5271 kcal, p <0.001).Conclusions
A single aerobic session seems to modify the spontaneous physical activities in overweight adolescents but still keeping the vigorous session with higher total energy expenditure during the follow-up period. Despite the observed compensatory effect, the greater energy expenditure observed in both moderate and vigorous exercise sessions indicates that physical activity should be recommended to promote an increased energy expenditure in adolescents.Trial Registration
ClinicalTrials.gov NCT 02272088相似文献123.
Raimundo Fernandes de Araújo Júnior Vinícius Barreto Garcia Renata Ferreira de Carvalho Leit?o Gerly Anne de Castro Brito Emilio de Castro Miguel Paulo Marcos Matta Guedes Aurigena Antunes de Araújo 《PloS one》2016,11(2)
Aim
To evaluate the anti-inflammatory, anti-oxidant and antifibrotic effects of carvedilol (CARV) in rats with ethanol-induced liver injury.Methods
Liver injury was induced by gavage administration of alcohol (7 g/kg) for 28 consecutive days. Eighty Wistar rats were pretreated with oral CARV at 1, 3, or 5 mg/kg or with saline 1 h before exposure to alcohol. Liver homogenates were assayed for interleukin (IL)-1β, IL-10, and tumor necrosis factor (TNF)-α level as well as for myeloperoxidase (MPO) activity and malonyldialdehyde (MDA) and glutathione (GSH) levels. Serum aspartate aminotransferase (AST) activity and liver triglyceride (TG) levels were also assayed. Immunohistochemical analyses of cyclooxygenase 2 (COX-2), receptor activator of nuclear factor kappa-B/ligand (RANK/RANKL), suppressor of cytokine signalling (SOCS1), the Kupffer cell marker IBA-1 (ionized calcium-binding adaptor molecule 1), intercellular adhesion molecule 1 (ICAM-1), superoxide dismutase (SOD-1), and glutathione peroxidase (GPx-1) expression were performed. Confocal microscopy analysis of IL-1β and NF-κB expression and real-time quantitative PCR analysis for TNFα, PCI, PCIII, and NF-κB were performed.Results
CARV treatment (5 mg/kg) during the alcohol exposure protocol was associated with reduced steatosis, hepatic cord degeneration, fibrosis and necrosis, as well as reduced levels of AST (p < 0.01), ALT (p < 0.01), TG (p < 0.001), MPO (p < 0.001), MDA (p < 0.05), and proinflammatory cytokines (IL-1β and TNF-α, both p < 0.05), and increased levels of the anti-inflammatory cytokine IL-10 (p < 0.001) and GSH (p < 0.05), compared to the alcohol-only group. Treatment with CARV 5 mg/kg also reduced expression levels of COX-2, RANK, RANKL, IBA-1, and ICAM-1 (all p < 0.05), while increasing expression of SOCS1, SOD-1, and GPx-1 (all p < 0.05) and decreasing expression of IL-1β and NF-κB (both, p < 0.05). Real-time quantitative PCR analysis showed that mRNA production of TNF-α, procollagen type I (PCI), procollagen type III (PCIII), and NF-κB were decreased in the alcohol-CARV 5 mg/kg group relative to the alcohol-only group.Conclusions
CARV can reduce the stress oxidative, inflammatory response and fibrosis in ethanol-induced liver injury in a rat model by downregulating signalling of Kuppfer cells and hepatic stellate cells (HSCs) through suppression of inflammatory cytokines. 相似文献124.
Summary A lactic starter culture of a flocculentLactobacillus plantarum was produced in a fluidized bed reactor with higher cell volumetric productivities than in a continuous stirred tank reactor. The fluidized bed reactor was operated at optimised parameters obtained in batch reactor performed with and without pH control. 相似文献
125.
A Uribe Barreto 《Plastic and reconstructive surgery》1991,87(3):583-584
126.
Leandro S. L. Hohl Fernando L. Sicuro Janaína C. Wickert Ignacio B. Moreno Oscar Rocha-Barbosa André S. Barreto 《Journal of morphology》2020,281(6):564-577
The bottlenose dolphin, genus Tursiops, is cosmopolitan occurring in tropical and temperate regions, with morphological variation between and within different oceans. Since the genus' taxonomy has been under discussion for a long time, this work aimed at analyzing the cranial variability of T. truncatus from different regions of the world. Geometric Morphometrics analyses were performed in 201 skulls of adult specimens, on dorsal, ventral, and lateral views, from the Eastern North Pacific, Eastern North Atlantic, Eastern South Atlantic, and Western South Atlantic oceans. The results indicate differences between individuals that inhabit the Atlantic and Pacific oceans. Within the Atlantic Ocean, there is an evident longitudinal differentiation of specimens from the eastern and western regions. A latitudinal separation was also observed, considering specimens from the North and South Atlantic Ocean. In the Western South Atlantic statistical differences were found between two morphological groups, identified as T. gephyreus (sensu Lahille, 1908) and T. truncatus, and the cross-validation presented 98% as minimum confidence for correct classification of these two groups. The present study provides strong morphological support to consider these two lineages as separate species. 相似文献
127.
128.
Gabriel Felipe Oliveira de Menezes Rodrigo Freitas Bittencourt Fernando de Lima Cardoso Maicon Pereira Lents Elisiane Sateles dos Santos Renata Oliveira Barreto Edivnia Oliveira de Jesus Mnica Madrigal Valverde Antonio de Lisboa Ribeiro Filho 《Animal Reproduction》2020,17(4)
Dimethylacetamide has been included in different extenders for the cryopreservation of semen from species with promising results. The objective of this study was to evaluate the use of dimethylacetamide (DMA) in different concentrations, associated or not with glycerol (GLY), for the cryopreservation of ovine semen, and its effects on in vitro sperm parameters and post-thaw in vivo fertility. Five semen samples of five adult Santa Ines sheep (n=25) were used. The collected ejaculates were divided among the seven treatments for subsequent cryopreservation. The treatments presented different concentrations of DMA and GLY, being divided as G1: GLY 6%; G2: DMA 3%; G3: GLY 5% + DMA 1%; G4: GLY 4% + DMA 2%; G5: GLY 3% + DMA 3%; G6: GLY 2% + DMA 4%; G7: GLY 1% + DMA 5%. %. Post-thawing of the straws, aliquots were evaluated for computerized sperm kinetics (CASA) and plasma membrane integrity, using fluorescent probes and flow cytometry. After the in vitro evaluation of the sperm parameters, in vivo testing was performed by laparoscopic artificial insemination of 72 females. The post-thaw total motility (%) evaluated by CASA were 51.4, 51.4, 50.1, 53.6, 52.3, 52.8 and 46.9, respectively, for the seven groups. And the plasma membrane integrity (%) were 19.7, 28.4, 22.3, 29.4, 24.3, 17.9 and 16.9, respectively. There were no differences (P> 0.05) between the treatments for the parameters of spermatic kinetics and membrane integrity. For females inseminated with semen from the control group (G1, GLY6%), the percentage of pregnant females was 36.1%, a result similar to that obtained with G3 treatment (GLY5% + DMA1%). In conclusion, dimethylacetamide, either alone or in combination with glycerol, can be used for cryopreservation of ovine semen. 相似文献
129.
130.
Elisangela G. F. Morais Marcelo C. Picanço Robert W. Barreto Gerson A. Silva Shaiene C. Moreno Renan B. Queiroz 《BioControl》2010,55(5):685-694
Miconia calvescens (Melastomataceae) is an invasive alien tree in native forests on some Pacific islands and a potentially invasive species
in Australia. Searches for potential classical biocontrol agents have been undertaken for over a decade in the centre of origin
(Central and South America). Salbia lotanalis (Lepidoptera: Pyralidae) is a leaf roller which has been recognized as a promising classical biocontrol agent for M. calvescens. This paper presents the biology and an impact study of S. lotanalis on M. calvescens. Life table parameters showed that S. lotanalis has a high reproductive capacity, with up to six generations a year. Miconia calvescens seedlings attacked by S. lotanalis caterpillars had their growth rate significantly reduced. Seedlings subjected initially to a high level of defoliation (80%)
caused by caterpillars had leaf fall and a lower leaf area than controls after 210 days. Considering the high population growth
rate and significant impact on young plants, S. lotanalis appears to have a high potential for use as a classical biological control agent to be used against M. calvescens. 相似文献