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991.
To identify potent and selective 5-HT(2C) receptor agonists, a series of novel benzazepine derivatives were synthesized, and their structure-activity relationships examined. The compounds were evaluated for their 5-HT(2C), 5-HT(2A), and 5-HT(2B) receptor binding affinity and intrinsic activity for the 5-HT(2C) and 5-HT(2A) receptors. Among these compounds, 6,7-dichloro-2,3,4,5-tetrahydro-1H-3-benzazepine (6) was effective in a rat penile erection model when administered po, which is a symptom of the serotonin syndrome reflecting 5-HT(2C) receptor activation. Moreover, compound 6 was characterized as a partial agonist of 5-HT(2A) receptors; therefore, it had little effect on the cardiovascular system.  相似文献   
992.
Accumulation of microarray data has enabled the computational analysis of gene expressions in various tissues. Although the genes showing testis-specific expression are most abundant among the genes exhibiting tissue-specific expression, no systematic study has been conducted for over-represented motifs within their regulatory regions. We have identified 117 over-represented 8-mers that appeared 2648 times within the regulatory regions of 634 testis-specific genes. Of these, 64 over-represented 8-mers were significantly more frequent in the regulatory regions of testis-specific genes than in those of non-testis-specific genes. In this group of 8-mers, 4 8-mers differed from the canonical cAMP response element (CRE) 8-mer by 1 letter, but the canonical CRE was not included in this group. We consider that CRE-like 8-mers participate in the regulatory expression of testis-specific genes to a greater extent than the canonical CRE 8-mer.  相似文献   
993.
994.
We found that a herbal medicine (Mao-to) relieves the side effects of interferon (IFN)-beta and the combination therapy improves the biochemical response rate. However, the exact mechanism by which Mao-to is effective remains to be established. We conducted a controlled trial to clarify the effects of Mao-to. The study was carried out in 18 patients with chronic hepatitis C, and we examined subjective symptoms, body temperature and cytokines such as interleukin (IL)-beta, IL-1receptor antagonist (ra), IL-6 and TNF-alpha. Each patient received 6 million units of IFN-beta intravenously. Mao-to was given orally just before, just after, and 1 hour after IFN administration. The control study was carried out 6 months after the combination therapy of Mao-to and IFN-beta. The scores for general malaise, arthralgia and discomfort were significantly lower in the combination group than in control group. Body temperature did not significantly differ between the two groups. Plasma IL-6 level and IL-1ra were significantly elevated in the combination group compared to control (P = 0.0057 and 0.0003, respectively). Mao-to did not affect plasma concentrations of IL-1beta and TNF-alpha. We considered the increment of IL-1ra caused by Mao-to is to be one of the key factors involved in reducing the flu-like symptoms accompanying IFN-beta and improving the biochemical response rate.  相似文献   
995.
Oil bodies in seeds of higher plants are surrounded with oleosins. Here we demonstrate a novel role for oleosins in protecting oilseeds against freeze/thaw-induced damage of their cells. We detected four oleosins in oil bodies isolated from seeds of Arabidopsis thaliana , and designated them OLE1, OLE2, OLE3 and OLE4 in decreasing order of abundance in the seeds. For reverse genetics, we isolated oleosin-deficient mutants ( ole1 , ole2 , ole3 and ole4 ) and generated three double mutants ( ole1 ole2 , ole1 ole3 and ole2 ole3 ). Electron microscopy showed an inverse relationship between oil body sizes and total oleosin levels. The double mutant ole1 ole2 , which had the lowest levels of oleosins, had irregular enlarged oil-containing structures throughout the seed cells. Germination rates were positively associated with oleosin levels, suggesting that defects in germination are related to the expansion of oil bodies due to oleosin deficiency. We found that freezing followed by imbibition at 4°C abolished seed germination of single mutants ( ole1 , ole2 and ole3 ), which germinated normally without freezing treatment. The treatment accelerated the fusion of oil bodies and the abnormal-positioning and deformation of nuclei in ole1 seeds, which caused seed mortality. In contrast, ole1 seeds that had undergone freezing treatment germinated normally when incubated at 22°C instead of 4°C, because degradation of oils abolished the acceleration of fusion of oil bodies during imbibition. Taken together, our findings suggest that oleosins increase the viability of over-wintering oilseeds by preventing abnormal fusion of oil bodies during imbibition in the spring.  相似文献   
996.
Metallothionein (MT) is a free radical scavenger induced by inflammatory stimuli; however, its roles in inflammation have not been fully investigated. In the present study, we genetically determined the role of MT in ozone (O3)-induced lung inflammation using MT-I/II null (–/–) mice. Subacute (65 h) exposure to O3 (0.3 ppm) induced lung inflammation and enhanced vascular permeability, which was significantly greater in MT(–/–) than in corresponding wild-type mice. Electron microscopically, O3 exposure induced vacuolar degeneration of pulmonary endothelial and epithelial cells, and interstitial edema with focal loss of the basement membrane, which was more prominent in MT(–/–) than in wild-type mice. O3 -induced lung expression of interleukin-6 was significantly greater in MT(–/–) than in wild-type mice; however, lung expression of the chemokines examined was comparable in both genotypes of mice in the presence of O3. Following O3 exposure, the formation of oxidative stress-related molecules/adducts, such as heme oxidase-1, inducible nitric oxide synthase, 8-hydroxy-2′-deoxyguanosine, and nitrotyrosine, in the lung was significantly greater in MT(–/–) than in wild-type mice. Collectively, MT protects against O3-induced lung inflammation, at least partly, via the regulation of pulmonary endothelial and epithelial integrity and its antioxidative property.  相似文献   
997.
A transposon-inserted mutant of Drosophila melanogaster was recently identified, and the larvae show no food preference (Ryuda and Hayakawa, 2005). To reveal the genetic mechanism underlying the preference change in this mutant, a large-scale oligo-DNA microarray screening was carried out to identify genes whose expression is different in control and mutant strains. We focused especially on hunger-driven changes in gene expression in the larval central nervous system (CNS) of both strains, because the state of food depletion should promote a feeding response due to changed expression of certain genes in the CNS. We identified 22 genes whose expression changed after starvation in either or both of the two strains. Quantitative RT-PCR analyses confirmed the expression changes in four genes, CG6271, CG6277, CG7953, and new glue 3 (ng3, encoding a putative structural molecule). CG6271 and CG6277 encode triacylglycerol lipase, and CG7953 produces a protein homologous to a juvenile hormone (JH) binding protein. The expression of these two groups of genes was enhanced in control strain larvae with a normal food preference but not in GS1189 strain larvae. Given that these genes contribute to mediating hunger-driven changes in food preference and intake in D. melanogaster larvae, the dysfunction of these key genes could cause the defect in food preference observed in GS1189-strain larvae.  相似文献   
998.
Starch branching enzyme (SBE) catalyzes the cleavage of alpha-1.4-linkages and the subsequent transfer of alpha-1.4 glucan to form an alpha-1.6 branch point in amylopectin. We overproduced rice branching enzyme I (BEI) in Escherichia coli cells, and the resulting enzyme (rBEI) was characterized with respect to biochemical and crystallographic properties. Specific activities were calculated to be 20.8 units/mg and 2.5 units/mg respectively when amylose and amylopectin were used as substrates. Site-directed mutations of Tyr235, Asp270, His275, Arg342, Asp344, Glu399, and His467 conserved in the alpha-amylase family enzymes drastically reduced catalytic activity of rBEI. This result suggests that the structures of BEI and the other alpha-amylase family enzymes are similar and that they share common catalytic mechanisms. Crystals of rBEI were grown under appropriate conditions and the crystals diffracted to a resolution of 3.0 A on a synchrotron X-ray source.  相似文献   
999.
Despite intensive research as to the pathogenesis of lipopolysaccharide (LPS)-related inflammation with coagulatory disturbance, their exacerbating factors have not been well explored. This study examined the effects of pulmonary exposure to two types of nano-sized materials (carbon nano-tubes: CNT [single-wall: SWCNT, and multi-wall: MWCNT]) on lung inflammation and consequent systemic inflammation with coagulatory disturbance induced by pulmonary exposure to LPS in mice and their cellular mechanisms in vitro. ICR male mice were divided into 6 experimental groups that intra-tracheally received the vehicle, two types of CNT (4 mg/kg), LPS (33 mu g/kg), or LPS plus either type of CNT. Twenty-four hours after treatment, both types of CNT alone induced lung inflammation with enhanced lung expression of proinflammatory cytokines, but did not synergistically exacerbate lung inflammation elicited by LPS. SWCNT significantly induced/ enhanced pulmonary permeability and hyperfibrinogenemia and reduced activated protein C in the absence or presence of LPS, whereas MWCNT did moderately. Both CNT moderately, but not significantly, elevated circulatory levels of proinflammatory cytokines and chemokines. In the presence of LPS, CNT tended to elevate the levels of the mediators with an overall trend, which was more prominent with SWCNT than with MWCNT. In vitro study showed that both CNT amplified LPS-induced cytokine production from peripheral blood monocytes. These results suggest that CNT can facilitate systemic inflammation with coagulatory disturbance, at least in part, via the activation of mononuclear cells, which is accompanied by moderate enhancement of acute lung inflammation related to LPS.  相似文献   
1000.
A sensitive liquid chromatography-electrospray ionization-tandem mass spectrometric (LC-ESI-MS-MS) method for the quantification of 17alpha-hydroxyprogesterone (17OHP) in human saliva has been developed and validated. The saliva was deproteinized with acetonitrile, purified using a Strata-X cartridge, derivatized with a highly proton-affinitive reagent, 2-hydrazinopyridine, and subjected to LC-MS-MS. Quantification was based on the selected reaction monitoring, and deuterated 17OHP was used as the internal standard. This method allowed the reproducible and accurate quantification of the salivary 17OHP using a 200-mul sample, and the limit of quantitation was 5.0 pg/ml. The developed method was applied to clinical studies. A linear relationship was found to be positive (r(2)=0.975) between the blood 17OHP level and the salivary 17OHP level measured using the proposed method. The result from the salivary 17OHP measurement in patients with congenital adrenal hyperplasia demonstrated that the proposed method is very useful for monitoring of the therapeutic efficacy during hormone replacement therapy.  相似文献   
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