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51.
Objective:We examined the role of vitamin D on volumetric bone mineral density (vBMD) and architecture during the first week’s post-fracture in postmenopausal women (PMW) with distal radial fractures (DRF) treated conservatively using peripheral Quantitative Computed Tomography (pQCT).Methods:Patients were classified into 2 groups according to initial median 25(OH)D level; Group A (25(OH)D ≥15 ng/ml) and group B (25(OH)D <15 ng/ml). All patients were followed for 12 weeks at three visits: baseline, 6 weeks and 12 weeks post fracture. pQCT was performed at baseline in fractured and contralateral non-fractured radius and at 6th and 12th week on the fractured side.Results:39 patients completed the protocol. Mean 25(OH)D levels were 15.60±7.35 ng/ml (3.5-41.7). Trabecular (trab) bone mineral content (BMC) and trabvBMD increased at 6 wk. vs. baseline (p<0.001). Cortical BMC, cortvBMD and cross- sectional area (CSA) progressively decreased (p<0.001) during the 12 weeks. There was no interaction between baseline 25(OH)D levels and changes in trabecular and cortical BMC, vBMD and CSA. Advanced age and higher CTX and P1NP were associated with higher cortical bone loss.Conclusion:Vitamin D deficiency does not affect the early architectural changes after a DRF. Advanced age and higher bone remodeling were associated with higher cortical bone loss, probably related to immobilization and independent of vitamin D levels.  相似文献   
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The phenomenon of autolysis in Blakeslea trispora during carotene production from deproteinized hydrolyzed whey in an airlift reactor was investigated. The process of cellular autolysis was studied by measuring the changes in carotene concentration, dry biomass, residual sugars, pH, intracellular protein, specific activity of the hydrolytic enzymes (proteases, chitinase), and micromorphology of the fungus using a computerized image analysis system. All these parameters were useful indicators of autolysis, but image analysis was found to be the most useful indicator of the onset and progress of autolysis in the culture. Autolysis of B. trispora began early in the growth phase, continued during the stationary phase, and increased significantly in the decline phase. The morphological differentiation of the fungus was a result of the degradation of the cell membrane by hydrolytic enzymes. The biosynthesis of carotenes was carried out in the exponential phase, where the phenomenon of autolysis was not intense.  相似文献   
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In the first part of the study, 24 clinically healthy teats from non-lactating ewe-lambs were examined bacteriologically and histologically. No bacteria were isolated from any of these teats; lymphocytes were observed in teat cisterns of six teats (25%) from three ewes. In the second part, 87 teats from adult ewes were examined; their origin was from lactating mammary glands with no bacteria isolated (n = 23), from glands after lactation with no bacteria isolated (n = 25), from lactating glands with bacteria isolated (n = 22) or from glands after lactation with bacteria isolated (n = 17). The salient histological feature was sub-epithelial leucocytic infiltration. In teat cisterns, lymphocytes were the predominant cell type and in teat ducts, lymphocytes and neutrophils were seen in equal proportions. Sub-epithelial lymphoid nodules, some with germinal centers, were detected in 43 (49%) teats; their majority was observed at the border between teat duct and teat cistern. Presence of bacteria was significantly associated with presence of leucocytic activity (P < 0.001) and with presence of lymphoid nodules (P = 0.032). We conclude that the presence of induced sub-epithelial lymphoid tissue at the border between teat duct and teat cistern appears to be important in protecting the mammary gland during the early stages of bacterial invasion.  相似文献   
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Recently, using a proteomic approach we have identified the corepressor Alien as a novel interacting factor of the cell cycle regulator E2F1. Unclear was whether this interaction influences cell proliferation and endogenous E2F1 target gene expression. Here, we show by chromatin immunoprecipitation (ChIP) that Alien is recruited in vivo to the E2F binding sites present in the E2F1 gene promoter, inhibits the transactivation of E2F1 and represses endogenous E2F1 gene expression. Interestingly, using synchronized cells to assess the expression of Alien profile during cell cycle the levels of endogenous Alien are increased during G1, G1/S and G2 phase. Furthermore, stable transfection of Alien leads to reduction of cell proliferation. Thus, the data suggest that Alien acts as a corepressor for E2F1 and is involved in cell cycle regulation.  相似文献   
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Smooth muscle α-actin (Acta2) is one of six highly conserved mammalian actin isoforms that appear to exhibit functional redundancy. Nonetheless, we have postulated a specific functional role for the smooth muscle specific isoform. Here, we show that Acta2 deficient mice have a remarkable mammary phenotype such that dams lacking Acta2 are unable to nurse their offspring effectively. The phenotype was rescued in cross fostering experiments with wild type mice, excluding a developmental defect in Acta2 null pups. The mechanism for the underlying phenotype is due to myoepithelial dysfunction postpartum resulting in precocious involution. Further, we demonstrate a specific defect in myoepithelial cell contractility in Acta2 null mammary glands, despite normal expression of cytoplasmic actins. We conclude that Acta2 specifically mediates myoepithelial cell contraction during lactation and that this actin isoform therefore exhibits functional specificity.  相似文献   
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Single strand conformation polymorphism (SSCP) is a reproducible, rapid and quite simple method for the detection of deletions/insertions/rearrangements in polymerase chain reaction amplified DNA. All the details for the use of PCR–SSCP are presented in the direction of genetic diseases (β-thalassaemia, cystic fibrosis), optimum gel conditions, sensitivity and the latest modifications of the method, which are applied in most laboratories. This non-radioactive PCR–SSCP method can be reliably used to identify mutations in patients (β-globin, CFTR), provided suitable controls are available. Moreover, it is widely used for mutation identification in carriers (β-thalassaemia, cystic fibrosis), making it particularly useful in population screening.  相似文献   
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We prepared a new series of renin inhibitors based on dipeptide glycols, replacing the P4-P3 subsites with an O-(N-morpholinocarbonyl)-3-L-phenyllactic acid residue. This modification proved bioisosteric with Boc-L-phenylalanine, giving rise to highly potent human renin inhibitors (1-5 nM), e.g., SC-46944 (IC50 = 5 nM). Moreover, this change produced compounds that are orally efficacious in reducing plasma renin activity in salt-depleted marmosets.  相似文献   
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