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21.
In this study, the synthesis and evaluation of a number of esters of CS-758 as injectable prodrugs are described. Phosphoryl ester 1a was soluble in water (>30 mg/mL) and was converted to CS-758 in human liver microsome. It was also converted to CS-758 in rats after iv administration, wherein the bioavailability of CS-758 was 53%. Compound 1a (iv) reduced the viable cell counts in kidneys in a murine systemic Candida albicans infection model, wherein the effect was comparable to or slightly superior to that of CS-758 (po). The prodrug 1a proved to be a promising injectable antifungal agent whose further evaluation is warranted.  相似文献   
22.
Skeletal muscles express estrogen receptor (ER) α and ERβ. However, the roles of estrogens acting through the ERs in skeletal muscles remain unclear. The effects of 17β-estradiol (E2) on myogenesis were studied in C2C12 myoblasts. E2 and an ERα-selective agonist propylpyrazole-triol depressed myosin heavy chain (MHC), tropomyosin, and myogenin levels and repressed the fusion of myoblasts into myotubes. ER antagonist ICI 182,780 cancelled E2-repressed myogenesis. E2 induced ubiquitin-specific peptidase 19 (USP19) expression during myogenesis. E2 replacement increased USP19 expression in the gastrocnemius and soleus muscles of ovariectomized mice. Knockdown of USP19 inhibited E2-repressed myogenesis. Mutant forms of USP19 lacking deubiquitinating activity increased MHC and tropomyosin levels. E2 decreased ubiquitinated proteins during myogenesis, and the E2-decreased ubiquitinated proteins were increased by knockdown of USP19. Propylpyrazole-triol increased USP19 expression, and ICI 182,780 inhibited E2-increased USP19 expression. Overexpression of ERα or knockdown of ERβ enhanced the effects of E2 on the levels of USP19, MHC, and tropomyosin, whereas knockdown of ERα, overexpression of ERβ, or an ERβ-selective agonist diarylpropionitrile abolished their effects. A mutant form of ERα that is constitutively localized in the nucleus increased USP19 expression and decreased MHC and tropomyosin expression in the presence of E2. Furthermore, in skeletal muscle satellite cells, E2 inhibited myogenesis and increased USP19 expression, and diarylpropionitrile repressed E2-increased USP19 expression. These results demonstrate that (i) E2 induces USP19 expression through nuclear ERα, (ii) increased USP19-mediated deubiquitinating activity represses myogenesis, and (iii) ERβ inhibits ERα-activated USP19 expression.  相似文献   
23.
Growing evidence indicates a moderate but significant relationship between processing speed in visuo-cognitive tasks and general intelligence. On the other hand, findings from neuroscience proposed that the primate visual system consists of two major pathways, the ventral pathway for objects recognition and the dorsal pathway for spatial processing and attentive analysis. Previous studies seeking for visuo-cognitive factors of human intelligence indicated a significant correlation between fluid intelligence and the inspection time (IT), an index for a speed of object recognition performed in the ventral pathway. We thus presently examined a possibility that neural processing speed in the dorsal pathway also represented a factor of intelligence. Specifically, we used the mental rotation (MR) task, a popular psychometric measure for mental speed of spatial processing in the dorsal pathway. We found that the speed of MR was significantly correlated with intelligence scores, while it had no correlation with one’s IT (recognition speed of visual objects). Our results support the new possibility that intelligence could be explained by two types of mental speed, one related to object recognition (IT) and another for manipulation of mental images (MR).  相似文献   
24.
Essential oils and hydrosols were extracted from rosemary harvested in different seasons, and the chemical compositions of volatile components in the two fractions were analyzed by gas chromatography–mass spectrometry (GC–MS). Enantiomers of some volatile components were also analyzed by enantioselective GC–MS. Classification of aroma components based on chemical groups revealed that essential oils contained high levels of monoterpene hydrocarbons but hydrosols did not. Furthermore, the enantiomeric ratios within some volatile components were different from each other; for example, only the (S)-form was observed for limonene and the (R)-form was dominant for verbenone. These indicate the importance of determining the enantiomer composition of volatile components for investigating the physiological and psychological effects on humans. Overall, enantiomeric ratios were determined by volatile components, with no difference between essential oils and hydrosols or between seasons.  相似文献   
25.
Six species of the genus Panonychus are known from Japan. Life-history parameters of all six species were investigated at 25 °C, and for three species two strains of different geographical origin were included. The intrinsic rate of natural increase (r m ) ranged from 0.172/day for the P. osmanthi albino strain to 0.209/day for P. citri, while the net reproductive rate (R 0) varied from 23.98 in the thelytokous species P. thelytokus to 46.61 in P. citri. Both values were higher in the polyphagous species (P. ulmi, P. mori and P. citri), which are considered crop pests, than those in the oligophagous species (P. thelytokus and P. osmanthi), considered non-pests. The only exception was P. bambusicola, an oligophagous non-pest species with R 0- and r m -values closely resembling those of the three polyphagous species. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
26.
To examine the effects of physical training on glucose effectiveness (S(G)), insulin sensitivity (S(I)), and endogenous glucose production (EGP) in middle-aged men, stable-labeled frequently sampled intravenous glucose tolerance tests (FSIGTT) were performed on 11 exercise-trained middle-aged men and 12 age-matched sedentary men. The time course of EGP during the FSIGTT was estimated by nonparametric stochastic deconvolution. Glucose uptake-specific indexes of glucose effectiveness (S(2*)(G) x 10(2): 0.81 +/- 0.08 vs. 0.60 +/- 0.05 dl. min(-1). kg(-1), P < 0.05) and insulin sensitivity [S(2*)(I) x 10(4): 24.59 +/- 2.98 vs. 11.89 +/- 2.36 dl. min(-1). (microU/ml)(-1). kg(-1), P < 0.01], which were analyzed using the two-compartment minimal model, were significantly greater in the trained group than in the sedentary group. Plasma clearance rate (PCR) of glucose was consistently greater in the trained men than in sedentary men throughout FSIGTT. Compared with sedentary controls, EGP of trained middle-aged men was higher before glucose load. The EGP of the two groups was similarly suppressed by approximately 70% within 10 min, followed by an additional suppression after insulin infusion. EGP returned to basal level at approximately 60 min in the trained men and at 100 min in the controls, followed by its overshoot, which was significantly greater in the trained men than in the controls. In addition, basal EGP was positively correlated with S(2*)(G) . The higher basal EGP and greater EGP overshoot in trained middle-aged men appear to compensate for the increased insulin-independent (S(2*)(G)) and -dependent (S(2*)(I)) glucose uptake to maintain glucose homeostasis.  相似文献   
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28.
The purpose of the present study was to investigate the relationship among intra-abdominal adipose storage, adaptation in the serum leptin concentration and skeletal muscle enzyme activity after a 4-week energy restriction (ER). Thirty-one male Wistar rats were divided into 40% energy restricted (n=24) or ad libitum-fed control (CL) rats (n=7). The energy-restricted rats were grouped into the most fat (MF, n=7), medium (n 10) and the least fat (LF, n=7) by their intra-abdominal fat pads mass (epididymal, mesenteric, and perirenal) after ER. A superficial portion of M. gastrocnemius tissue obtained before and after the diet period were analyzed to determine the activities of hexokinase (HK), beta-hydroxyacyl CoA dehydrogenase (beta-HAD) and citrate synthase (CS). Blood samples were also collected for a serum leptin assay. At the baseline, no difference was found in either the leptin concentration or the enzyme activities among LF, MF and CL. The serum leptin concentration was positively correlated with the muscle activities of beta-HAD and CS, while it negatively correlated with HK/beta-HAD. After ER, the activities of HK, beta-HAD and CS were all significantly lower in LF than in CL. Among the energy-restricted rats, the intra-abdominal fat pad weight, leptin concentration and the activities of beta-HAD, CS, beta-HAD/CS all significantly correlated with one another. The changes in leptin and the activity of beta-HAD were also positively correlated. These findings indicate that parallel decreases in the serum leptin and skeletal muscle enzyme activities with the energy restriction-induced intra-abdominal adipose reduction, thus may suggest the leptin to have a regulative effect on the muscle enzyme activity during ER.  相似文献   
29.
A 410-nm absorbing species which enhanced the reduction rate of cytochrome c by Old Yellow Enzyme (OYE) with NADPH was found in Saccharomyces cerevisiae. It was solubilized together with OYE by the treatment of yeast cells with 10% ethyl acetate. The purified species showed visible absorption spectra in both oxidized and reduced forms, which were the same as those of the yeast microsomal cytochrome b5. At least 14 amino acid residues of the N-terminal region coincided with those of yeast microsomal b5, but the protein had a lower molecular weight determined to be 12,600 by SDS-PAGE and 9775 by mass spectrometry. The cytochrome b5-like protein enhanced the reduction rate of cytochrome c by OYE, and a plot of the reduction rates against its concentration showed a sigmoidal curve with an inflexion point at 6x10(-8) M of the protein.  相似文献   
30.
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