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951.
952.

Escitalopram has been shown to be effective for treating major depression (MDD); however, research is lacking regarding its effect on treating MDD-related sleep impairments. The purpose of this study was to assess the efficacy of escitalopram monotherapy and investigate changes in insomnia, depressive symptoms, and quality of life (QOL). Participants were 14 patients with MDD who enrolled in a clinical trial at Jikei University Katsushika Medical Center. Escitalopram monotherapy was used, and hypnotics were administered three times per week for individuals suffering from sleep impairments. The following variables were assessed: (1) sleep quality [Pittsburgh sleep quality index (PSQI)], (2) depression [Zung self-rating depression scale (ZSRDS)], and (3) quality of life (QOL) as determined by the Sheehan disability scale (SDISS) and short form (36) health survey (SF-36). These assessments were conducted prior to any treatment (pre-test) and again 8–12 weeks after treatment (post-test). Monotherapy (E = escitalopram alone; n = 6) and combination therapy (E+ = escitalopram + zolpidem; n = 8) groups were compared. All participants completed the full protocol (average 9.4 ± 1.8 weeks). Regardless of treatment group, participants improved on all assessments (including sleep impairment). However, groups did not differ in their level of improvement. A two-factor ANOVA revealed that the E+ group showed particular improvements in QOL. In treating MDD and associated sleep impairments, zolpidem did not confer additional benefits. Thus, clinicians should consider E monotherapy for patients with MDD-related sleep impairments before prescribing combination therapies.

  相似文献   
953.
The torsional and bending rigidities of Z-form DNA have been studied by nanosecond fluorescence anisotropy measurements of intercalated ethidium. The results suggested that Z-form DNA was considerably more flexible than B-form DNA. We have investigated the temperature dependence of the rigidity of B- and Z-form DNA and found that the temperature dependence of the torsional rigidity of Z-form DNA was remarkably lower than that of B-form DNA.  相似文献   
954.
955.
The conformational changes of GroEL during the ATPase cycle in the presence of GroES were studied by measuring the fluorescence intensity time course of intrinsic tyrosine Y506, which is located near the nucleotide-binding site. A GroEL solution containing GroES was mixed with an ATP solution to initiate the reaction cycle. The tyrosine fluorescence intensity relative to that without the nucleotide reached 112% within the dead time of the apparatus (>15 s?1) and further increased to 123% at 0.57 s?1 followed by a decrease to 102% at 0.32 s?1. An initial conformational change and a second intermediate state were expected to occur in ATP-bound GroEL because similar changes were observed for the ATPase-deficient D398A mutant. The conformational change to the third intermediate state corresponded to a process during or after ATP hydrolysis because D398A had no decreasing phase. The second intermediate state before ATP hydrolysis was characterized for the first time.  相似文献   
956.
Adipocytes forming fat pad in vivo are surrounded by well developed basement membranes. Synthesis of basement membrane is enhanced during in vitro differentiation of preadipocyte line. In order to know the role of basement membrane in adipogenesis in vivo, we injected 3T3-F442A preadipocytes subcutaneously into nude mice together with or without the reconstituted basement membrane, Matrigel. Histological sections of the fat pads newly formed by injecting the cell alone showed dense population of immature adipocytes and microvessels within 2 weeks and they matured rapidly. In contrast, injection of the cells together with Matrigel showed sparse adipocytes after 2 weeks and they matured slowly over the period of 6 weeks. Quantification of the process by measuring the weight, DNA content, triglyceride content and glycerophosphate dehydrogenase (GPDH) activity of the fat pads showed that injection of the cell alone resulted in early maturation of adipose tissue with fewer adipocytes while the presence of Matrigel decelerated but potentiated the maturation of adipose tissue with 2 fold contents of DNA, triglyceride and GPDH activity. We thus showed that reconstituted basement membrane (Matrigel) supported the survival and maturation of adipocytes. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
957.
The macromolecular permeability of cultured bovine aortic, bovine venous, and human umbilical vein endothelial cell monolayers was decreased significantly in culture medium containing L-ascorbic acid (Asc Acid; 0.01–0.1 mM) and L-ascorbic acid 2-phosphate (Asc 2-P). Dithiothreitol, which shows reducing activity equivalent to that of Asc Acid, did not affect endothelial permeability. Asc Acid induced a sixfold increase in collagen synthesis by the endothelial cells. The coexistence of L-azetidine 2-carboxylic acid, an inhibitor of collagen synthesis, attenuated the effect of Asc 2-P in a dose-dependent manner. Another collagen synthesis inhibitor, ethyl-3,4-dihydroxybenzoate, also inhibited collagen synthesis and increased endothelial permeability. The decrease in permeability of the endothelial monolayer was dependent on a reduction of the permeability coefficient of the endothelial monolayer. These findings indicate that endothelial barrier function is stimulated by Asc Acid via an increase in collagen synthesis. © 1995 Wiley-Liss, Inc.  相似文献   
958.
Molecular glue for DNA is a small synthetic ligand that adheres two single-stranded DNAs to produce a double-stranded DNA. We previously devised a photoswitchable molecular glue (PMG) that uses external light stimuli to reversibly control DNA hybridization. To optimize the structure of PMG, we synthesized a series of PMGs and evaluated the effect of changing the methylene linker length on the binding affinity and photoresponse. From the comprehensive Tm and CSI-TOF-MS measurements, a PMG possessing a three-methylene linker with carbamate linkage produced maximum binding affinity and photoswitching ability. These results indicate that a small difference in the linker can significantly affect PMG function. These findings are useful for designing new photoswitchable DNA-binding ligands.  相似文献   
959.
960.
Ubiquitin is a small protein involved in intracellular proteolysis. It is highly conserved throughout eukaryotic phyla and has been detected in such diverse species as yeast, barley, Drosophila and man. A previous study showed that chromatin of rainbow trout testis contains free ubiquitin with a sequence similar to that of other phyla. In the present study, which focused on rainbow trout but included eleven other species, it is shown that fish ubiquitin genetic organisation and expression are similar to those of other phylogenetic groups through the following set of observations: (a) Multiple loci were detected, (b) These loci encode repeats of ubiquitin, (c) Although the DNA sequences are not conserved, the encoded amino acid sequences are fully conserved, (d) The expression of ubiquitin was influenced by cell culture conditions and viral infection.  相似文献   
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