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排序方式: 共有347条查询结果,搜索用时 93 毫秒
141.
Michelle Karen Brasil Serafim Valdevane Rocha Araújo Ana Beatriz Graça Duarte Roberta Nogueira Chaves Cláudio Afonso Pinho Lopes Lúcia Daniel Machado da Silva 《Theriogenology》2010,74(5):749-47
The objective was to evaluate the effects of various concentrations of exogenous FSH during in vitro culture of isolated canine preantral follicles. Preantral secondary follicles (>200 μm) were isolated by microdissection and cultured for 18 d in supplemented α-Minimum Essential Medium (α-MEM). There were three treatment groups: 1) absence of FSH (control medium); 2) FSH100 (fixed concentration of 100 ng/mL throughout the entire culture period); and 3) sequential FSH (FSHSeq - 100, 500, and 1,000 ng/mL were added sequentially). Following culture, all follicles from all treatments were still viable (marked green by calcein-AM). The initial (D0) average follicle diameter for the control, FSH100, and FSHSeq was (mean ± SEM) 298.96 ± 7.02, 286.00 ± 5.87, and 275.39 ± 174 6.55 um, respectively (P > 0.05). Mean diameter of follicles treated with FSHSeq on Day 18 (D18-439.80 ± 14.08 μm) was greater than those of the other treatments (P < 0.05). Daily follicular growth rate (μm/d) of follicles in the FSHSeq treatment (6.47 ± 0.55) was significantly faster than for both the control (3.67 ± 0.32) and FSH100 (4.47 ± 0.38) treatments. Furthermore, FSH100 and FSHSeq treatments had a significantly higher rate of antrum formation than the control group on D12 of culture, whereas after D12, FSH100 had a significantly higher rate of extrusion compared to the control (P < 0.05). In conclusion, the sequential addition of FSH to the culture medium maintained the survival of isolated canine preantral follicles and promoted an increased rate of follicular growth and antrum formation. 相似文献
142.
de Pinho RS da Silva-Júnior FP Bastos JP Maia WS de Mello MT de Bruin VM de Bruin PF 《Chronobiology international》2006,23(5):963-971
Truck drivers are more likely to suffer severe injury and death due to certain truck driving characteristics. Identifying and preventing factors associated with accidents in this population is important to minimize damage and improve road safety. Excessive daytime sleepiness is a major public health problem, leading to impaired cognitive function, reduced alertness, and increased risk of motor vehicle crashes. The aim of this cross-sectional study was to determine the prevalence and predictors of hypersomnolence (defined as an Epworth Sleepiness Scale score greater than 10) among truck drivers. Three hundred male truck drivers were studied. Quality of sleep was assessed by the Pittsburgh Sleep Quality Index, and the association between demographic, clinical, and occupational data with excessive sleepiness was analyzed. The mean daily sleep duration was 5.6+/-1.3 h, and poor quality of sleep was found in 46.3% of the individuals. Hypersomnolence was found in 46% of the drivers and was associated with younger age, snoring, and working >10 h without rest. A positive correlation between hypersomnolence and previous accidents was detected (p=0.005). These results show that sleep deprivation and hypersomnolence are frequent among truck drivers. The treatment of sleep-disordered breathing and the implementation of educational programs, particularly targeting younger drivers and promoting increased awareness of the deleterious effects of sleep loss and work overload, may help to reduce hypersomnolence and accidents among truck drivers. 相似文献
143.
Pinho RA Andrades ME Oliveira MR Pirola AC Zago MS Silveira PC Dal-Pizzol F Moreira JC 《Cell biology international》2006,30(10):848-853
The association between physical exercise and oxidative damage in the skeletal musculature has been the focus of many studies in literature, but the balance between superoxide dismutase and catalase activities and its relation to oxidative damage is not well established. Thus, the aim of the present study was to investigate the association between regular treadmill physical exercise, oxidative damage and antioxidant defenses in skeletal muscle of rats. Fifteen male Wistar rats (8-12 months) were randomly separated into two groups (trained n=9 and untrained n=6). Trained rats were treadmill-trained for 12 weeks in progressive exercise (velocity, time, and inclination). Training program consisted in a progressive exercise (10 m/min without inclination for 10 min/day). After 1 week the speed, time and inclination were gradually increased until 17 m/min at 10% for 50 min/day. After the training period animals were killed, and gastrocnemius and quadriceps were surgically removed to the determination of biochemical parameters. Lipid peroxidation, protein oxidative damage, catalase, superoxide dismutase and citrate synthase activities, and muscular glycogen content were measured in the isolated muscles. We demonstrated that there is a different modulation of CAT and SOD in skeletal muscle in trained rats when compared to untrained rats (increased SOD/CAT ratio). TBARS levels were significantly decreased and, in contrast, a significant increase in protein carbonylation was observed. These results suggest a non-described adaptation of skeletal muscle against exercise-induced oxidative stress. 相似文献
144.
Soares AC Souza DG Pinho V Vieira AT Nicoli JR Cunha FQ Mantovani A Reis LF Dias AA Teixeira MM 《Microbes and infection / Institut Pasteur》2006,8(5):1321-1329
The long pentraxin PTX3 is expressed during acute inflammation and appears to control nitric oxide (NO) and tumor necrosis factor (TNF)-alpha production. In the present study, the physiological function of PTX3 was investigated in a model of pulmonary infection caused by the Gram-negative bacterium Klebsiella pneumoniae. Transgenic mice expressing multiple copies of PTX3 under the control of its own promoter were used to assess lethality rates, bacterial counts and inflammatory indices following pulmonary infection of mice. Expression of PTX3 is enhanced during pulmonary infection in wild-type mice. In transgenic mice given a high inoculum, overt PTX3 expression was associated with faster lethality. Faster lethality correlated with enhanced nitrate in plasma, an inability of neutrophils to migrate to lung tissue and greater dissemination of bacteria to blood at 20h after infection. In contrast, transgenic PTX3 expression conferred protection to mice given lower pulmonary inocula. In the latter experiments, there was enhanced TNF-alpha production, greater neutrophil influx and phagocytosis of bacteria by migrated neutrophils. By controlling the production of TNF-alpha and NO, and depending on the intensity of the inflammatory response induced by a given inoculum, the expression of PTX3 may favor or disfavor the influx of neutrophils and the ability of the murine host to deal with pulmonary infection with K. pneumoniae. These experiments highlight the delicate balance that exists among the various mediators that control the inflammatory response and suggest that PTX3 is an essential part of the ability of a host to deal with bacterial infection. 相似文献
145.
Alexandre Pinho Moura Geraldo Andrade Carvalho Adriano Elias Pereira Luiz Carlos Dias Rocha 《BioControl》2006,51(6):769-778
The effects of the insecticides abamectin, acetamiprid, cartap and chlorpyrifos on larvae, pupae (within the host egg) and
adults of the egg parasitoid Trichogramma pretiosum Riley (Hym.: Trichogrammatidae) were evaluated under laboratory conditions, using three standard tests described by IOBC.
When sprayed on the immature stages of this parasitoid, cartap and chlorpyrifos proved to be the most harmful insecticides,
affecting both the emergence success and parasitism capacity of this parasitoid, whereas abamectin and acetamiprid were selective.
Abamectin was harmful to adults (residue test on glass plates), slightly harmful to larvae, and moderately harmful to pupae
(sprayed on the immature stages within host eggs Anagasta kuehniella (Zeller)); acetamiprid was moderately harmful to adults, harmless to larvae, and slightly harmful to pupae; cartap was harmful
to adults, moderately harmful to larvae and harmful to pupae; chlorpyrifos to adults, harmless to larvae and harmful to pupae. 相似文献
146.
Two aspartyl proteases activities were identified and isolated from Trypanosoma cruzi epimastigotes: cruzipsin-I (CZP-I) and cruzipsin-II (CZP-II). One was isolated from a soluble fraction (CZP-II) and the other was solubilized with 3-[(3-cholamidopropyl)-dimethylammonio]-1-propanesulfonate (CZP-I). The molecular mass of both proteases was estimated to be 120 kDa by HPLC gel filtration and the activity of the enzymes was detected in a doublet of bands (56 and 48 kDa) by substrate-sodium dodecyl sulphate-polyacrylamide-gelatin gel electrophoresis. Substrate specificity studies indicated that the enzymes consistently hydrolyze the cathepsin D substrate Phe-Ala-Ala-Phe (4-NO2)-Phe-Val-Leu-O4MP but failed to hydrolyze serine and other protease substrates. Both proteases activities were strongly inhibited by the classic inhibitor pepstatin-A (?68%) and the aspartic active site labeling agent, 1,2-epoxy-3-(phenyl-nitrophenoxy) propane (?80%). These findings show that both proteases are novel T. cruzi acidic proteases. The physiological function of these enzymes in T. cruzi has under investigation. 相似文献
147.
148.
Cíntia Bittar Ana Carolina Gomes Jardim Lilian Hiromi Tomonari Yamasaki Claudia Márcia Aparecida Carareto Jo?o Renato Rebello Pinho Philippe Lemey Isabel Maria Vicente Guedes de Carvalho-Mello Paula Rahal 《PloS one》2013,8(4)
Background
Hepatitis C is a disease spread throughout the world. Hepatitis C virus (HCV), the etiological agent of this disease, is a single-stranded positive RNA virus. Its genome encodes a single precursor protein that yields ten proteins after processing. NS5A, one of the non-structural viral proteins, is most associated with interferon-based therapy response, the approved treatment for hepatitis C in Brazil. HCV has a high mutation rate and therefore high variability, which may be important for evading the immune system and response to therapy. The aim of this study was to analyze the evolution of NS5A quasispecies before, during, and after treatment in patients infected with HCV genotype 3a who presented different therapy responses.Methods
Viral RNA was extracted, cDNA was synthesized, the NS5A region was amplified and cloned, and 15 clones from each time-point were sequenced. The sequences were analyzed for evolutionary history, genetic diversity and selection.Results
This analysis shows that the viral population that persists after treatment for most non-responder patients is present in before-treatment samples, suggesting it is adapted to evade treatment. In contrast, the population found in before treatment samples from most end-of-treatment responder patients either are selected out or appears in low frequency after relapse, therefore changing the population structure. The exceptions illustrate the uniqueness of the evolutionary process, and therefore the treatment resistance process, in each patient.Conclusion
Although evolutionary behavior throughout treatment showed that each patient presented different population dynamics unrelated to therapy outcome, it seems that the viral population from non-responders that resists the treatment already had strains that could evade therapy before it started. 相似文献149.
150.
Salomé S. Pinho Joana Figueiredo Joana Cabral Sandra Carvalho Joana Dourado Ana Magalhães Fátima Gärtner Ana Maria Mendonça Tomoya Isaji Jianguo Gu Fátima Carneiro Raquel Seruca Naoyuki Taniguchi Celso A. Reis 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013