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991.
992.
A pentavalent human–bovine reassortant oral rotavirus vaccine, RotaTeq®, was evaluated among nearly 70,000 infants in the Rotavirus Efficacy and Safety Trial (REST), of which 30,523 were from Europe. All infants were followed for serious adverse events as well as hospitalizations and emergency department (ED) visits. All adverse events, health care utilization, and RVGE regardless of severity were evaluated in the clinical efficacy cohort (N = 2686) in Finland. RotaTeq® was 98.3% (95% CI, 90.2–100%) and 68.0% (95% CI 60.3–74.4%) efficacious against severe rotavirus gastroenteritis (RVGE) and all RVGE due to any serotype for two rotavirus seasons post-vaccination. The combined rate of hospitalizations and ED visits due to RVGE of any serotype was reduced by 94.5% (95% CI, 91.3–96.8%) for up to 2 years after vaccination. There were no statistically significant differences between RotaTeq® and placebo for any of the safety outcomes. In Europe, RotaTeq® was highly efficacious and well tolerated.  相似文献   
993.
BackgroundWhile physical activity is recommended to reduce symptomology associated with multiple sclerosis (MS) little has been done to explore the potential usefulness of theoretical models of exercise behavior change in individuals with MS. Based on the success of the transtheoretical model of exercise behavior change (TTM) in the general population and early promising results in those with MS, the TTM was tested in a sample of women with MS over a 1-year period, to examine its usefulness and the effect of TTM constructs on MS-related symptoms.MethodsThis was a longitudinal study conducted over a 1-year period. Ambulatory women (N = 86) with MS completed questionnaires assessing exercise behavior, TTM constructs, MS-related quality of life, pain, and fatigue at baseline and after 1 year. After categorization into transitional shift patterns reflecting naturally occurring exercise behavior change over the year, a series of mixed-design analyses of variance were conducted to examine TTM predictions and the relationship of the transitional shift patterns to MS-related quality of life, pain, and fatigue.ResultsSignificant interactions between transitional shift patterns and time (P < .05) indicated that changes in behavioral and cognitive processes of change and in self-efficacy were consistent with TTM predictions. Significant differences (P < .05) between the transitional shift groups in pain and fatigue in expected directions were also found.ConclusionsResults supported the TTM proposed relationships, indicating the model's potential for motivating individuals with MS to increase their physical activity. Findings also support the notion that physical activity is useful in reducing MS-related symptoms and that lifestyle types of physical activity may be as useful as structured exercise in bringing about these outcomes.  相似文献   
994.
Undifferentiated sarcomas are primitive mesenchymal tumors that cannot be classified among standardized histopathologic entities. Whether they represent a homogeneous group with common histogenesis and clinical behavior or comprise a variety of tumors able to differentiate along specific maturative lineages is still debated. To identify prognostic and histogenetic markers, we analyzed 7 undifferentiated sarcomas (4 in the trunk and 3 in the extremities). Mean patient age was 7.5 years, and mean follow-up was 18 months. Two clinicopathologic subtypes emerged from this study. Four primitive mesenchymal undifferentiated sarcomas arose mainly on the trunk and very proximal extremities, had an aggressive clinical course with poor outcome (3 deaths from disease, 1 with persistent disease), and displayed sheets of oval cells, with bland nuclei. Three spindle cell undifferentiated sarcomas arose on the extremities, had a favorable outcome, and showed elongated spindle cells with areas of primitive fibrosarcoma. All were negative for epithelial membrane antigen, cytokeratins, CD34, smooth muscle actin, desmin, Myf4, and HMB45 and showed nuclear staining for INI. Focal staining for S100 and CD99 was found in 3 and 4, respectively. Among stem cell markers, CD117 was positive in 3 cases (1 primitive, 2 spindle), nestin in 5 cases (4 primitive, 1 spindle), and CD105-stained tumor cells lining newly formed vascular spaces in 4 cases (1 primitive, 3 spindle). Survivin was weakly expressed in 6 cases and reflected low levels of mRNA (median survivin/GAPDH ratio, 1.096). Cytogenetic analysis revealed nonspecific translocations in 3 tumors. No translocations associated with Ewing sarcoma, synovial sarcoma, or alveolar rhabdomyosarcoma were found. In summary, primitive undifferentiated sarcomas occur in the trunk, behave aggressively, and express nestin. Spindle cell undifferentiated sarcomas occur in extremities, have a favorable outcome, resemble fibrosarcomas, and have similarly low survivin levels and display CD105-positive vascular spaces, which may represent an early hemangiopericytomatous pattern.  相似文献   
995.
Metabolic syndrome is characterized by increased cardiovascular risk. Pentraxin 3 (PTX3), an acute phase protein, is involved in atherosclerosis. No information is available on PTX3 plasma concentrations in metabolic syndrome and on its associations with metabolic alterations and subclinical atherosclerosis. The aim of this study was to assess PTX3 plasma levels in metabolic syndrome patients compared to control subjects and their potential associations with anthropometric and clinical components of the syndrome as well as with carotid artery intima-media thickness (cIMT), a marker of subclinical atherosclerosis. Plasma was obtained from metabolic syndrome patients (NCEP-ATP III criteria n = 41, 20 M/21F) and by age-matched control subjects (n = 32, 16 M/16F). PTX3 was measured using sandwich ELISA and cIMT with ultrasound. Compared to those of the control subjects, plasma levels of PTX3 were higher (+~100%, P = 0.0009) in metabolic syndrome patients. In univariate analysis, plasma PTX3 was negatively (P = 0.005) associated with high-density lipoprotein (HDL) cholesterol and positively (P = 0.046) with plasma triglycerides and with cIMT (P = 0.045) in the patients (n = 41). In multivariate analysis the direct association between PTX3 and cIMT was no longer significant after correction for HDL. None of these associations were detected in the control patients. These data demonstrate that PTX3, a novel marker of vascular disease, is higher in patients with metabolic syndrome associated with subclinical atherosclerosis. In addition, PTX3 is significantly independently correlated with low HDL cholesterol, but not with cIMT, suggesting a novel association between PTX3 and atherogenic lipid profile.  相似文献   
996.
In Escherichia coli and most Gram-negative bacteria, KDO (3-deoxy-D-manno-octulosonate), a component of the lipopolysaccharide inner core, is essential for outer membrane biogenesis and cell viability. Two recently identified genes involved in KDO biosynthesis, kdsD and kdsC, belong to the yrbG-yhbG locus where four additional ORFs (yrbG, yrbK, yhbN and yhbG) with unknown function are located. We have constructed six conditional expression mutants in which the arabinose-inducible araBp promoter is respectively located upstream of each gene of the locus. Complementation analysis of these mutants indicates that the locus is organized in at least three operons and that the three distal genes (yrbK, yhbN and yhbG) are essential for E. coli viability. Surprisingly, kdsD and kdsC (encoding a D-arabinose 5-phosphate isomerase and a KDO 8-phosphate phosphatase, respectively) were shown to be non-essential, indicating genetic redundancy for these two functions. A preliminary characterization of the arabinose-dependent mutants under permissive conditions and upon depletion revealed increased sensitivity to hydrophobic toxic chemicals, suggesting that the mutants have a defective outer membrane. These genes may thus be implicated in cell envelope integrity.  相似文献   
997.
998.
Zona glomerulosa (ZG) cells cultured on plastic within few days dedifferentiate losing their capacity to secrete aldosterone (ALDO) in appreciable amounts. Evidence indicates that extracellular matrix modulates the secretory behavior of adrenocortical cells cultured in vitro. Hence, we compared the morphology and function of rat ZG cells grown on plastic and Matrigel basement membrane matrix (hereinafter Matrigel) for up to 12 days. At day 3, no significant differences were observed between cells cultured on plastic and Matrigel. Starting from day 6, ZG cells cultured on plastic lost their ultrastructural differentiated features (mitochondria with tubular cristae, smooth endoplasmic reticulum cisternae and lipid droplets), exhibiting a fibroblast-like appearance. The mRNA expression of the main steroidogenic enzymes, as evaluated by real-time polymerase chain reaction, the baseline secretion of ALDO and other post-pregnenolone hormones, as evaluated by high pressure liquid chromatography, and the secretory response to ACTH, angiotensin-II and K(+), as evaluated by radioimmunoassay, displayed a time-dependent decrease. Matrigel was found to maintain unchanged both the ultrastructure and the expresion of steroidogenic enzymes of ZG cells until day 12 of culture. Baseline and agonist-stimulated steroid-hormone secretion decreased with the duration of culture on Matrigel, but was always higher than that of ZG cells grown on plastic. Hence, our study clearly indicates that the culture on Matrigel favors the maintenance of rat ZG-cell differentiated phenotype, allowing the conclusion that this technique is suitable for long-term in vitro investigations.  相似文献   
999.
The stem cell factor (SCF), besides regulating hemopoietic stem cells homing and proliferation, has proliferative effects on hepatocytes and may be involved in liver regeneration. We investigate if liver transplantation (LT) and hepatic resection (HR) modify the concentration of soluble SCF (s-SCF) in peripheral blood of 15 LT and 7 HR. s-SCF was measured by ELISA as ng/ml. s-SCF basal levels were higher in LT that in HR (818 +/- 349 vs. 479 +/- 79, p = 0.005). A significant increase of s-SCF, peaking at postoperative day +3, was seen after LT (from 818 +/- 349 to 1212 +/- 461, p = 0.01) and HR (from 479 +/- 79 to 698 +/- 122, p = 0.004). s-SCF peak levels were higher after LT than HR (p = 0.0008). At day +7 s-SCF concentration returned to baseline values. LT have a higher basal s-SCF level than HR. These data show for the first time that liver injury affects s-SCF level and suggest that SCF may be involved also in clinical liver regeneration.  相似文献   
1000.
BACKGROUND: Although the importance of estrogens in male reproduction is indisputable, little attention has been paid to the role of estrogen receptor (ER) gene mutations in male infertility. Significant correlation between (TA)n repeat allelic variants and lumbar bone mineral density was previously observed in the promoter region of the ERalpha gene, indicating that allelic combinations with higher number of (TA)n repeats are functionally more active genetic variants. METHODS: We studied the (TA)n repeat polymorphism situated in the promoter region of the ERalpha gene in a large group of infertile and normospermic men (n = 347). RESULTS: Although the (TA)n polymorphism failed to show a significant association with male infertility, we found a significant effect of this polymorphism on sperm count. In the group of infertile men, the mean TA repeat number and sperm concentration (P = 0.022) and total sperm number (P = 0.043) were inversely correlated, showing an association between higher TA repeat number (genotype A) and lower sperm production. In line with this observation, normospermic subjects with genotype A had a significantly lower mean sperm concentration with respect to men bearing genotype B with shorter TA alleles (P < 0.05) and a lower total sperm count (P < 0.01). CONCLUSIONS: Our data indicate that specific allelic combinations of the ERalpha, which confer a stronger estrogen effect, may negatively influence human spermatogenesis.  相似文献   
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