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861.
To investigate the associations of uncoupling protein (UCP)2 and UCP3 gene variants with overweight and related traits, we genotyped UCP2−866G>A, UCP2Ala55Val, and UCP3−55C>T in 737 Korean children and 732 adults and collected data regarding anthropometric status and blood biochemistry. Information concerning the children's lifestyles and dietary habits was collected. The UCP2−866G>A and UCP3−55C>T gene variants showed significant associations with BMI level, waist circumference, and body weight in the children but not in the adults. Compared with −866GG carriers, the −866GA and AA carriers showed a strong decreasing trend in the risk for overweight (odds ratio (OR), 0.67; 95% confidence interval (CI), 0.45–1.01; P = 0.053). In comparison with UCP3−55CC carriers, children carrying −55CT and TT showed a significant reduction in the risk of overweight (OR, 0.67; 95% CI, 0.46–0.98; P = 0.039). There was also evidence of interactions between the effects of the combined UCP2−UCP3 genotype and obesity‐related metabolic traits. The greatest protective effect against overweight was seen in those with the combined genotype non‐UCP2−866GG and non‐UCP3−55CC, as compared with those carrying both UCP2−866GG and UCP3−55CC (OR, 0.60; 95% CI, 0.38–0.95; P = 0.030). In the subgroup with a low level of physical activity, UCP3−55CC carriers had higher BMI values than UCP3−55T carriers (16.6 ± 2.3 kg/m2 vs. 16.1 ± 1.9 kg/m2, P = 0.016). Low physical activity may aggravate the susceptibility to overweight in UCP2−866GG and UCP3−55CC carriers.  相似文献   
862.
863.
TGF‐β3, TβR‐I, and TGF‐β‐activated Smad2 has been suggested to be a series of signaling molecules for secondary palate fusion. In this article, we show that a gene induced by TGF‐β, βig‐h3, is coincidentally expressed with TGF‐β3 in medial edge epithelial (MEE) cells undergoing apoptosis during normal palatal fusion. βig‐h3 was also highly expressed in the areas of post‐weaning mammary gland cells and developing phalangeal joints in which TGF‐β3 or BMP‐4‐induced apoptosis occurs, respectively. Blocking of βig‐h3 expression in E12.5 embryos with antisense oligodeoxynucleotides (ODN) resulted in cleft of the secondary palate in 84% of the treated mice that were born. Moreover, the antisense ODN treatment resulted in a failure of apoptosis in the MEE between palatal shelves in physical contact in organ culture. We conclude that βig‐h3 expression in the MEE is stimulated by TGF‐β3, causes cell death, and consequently results in complete fusion of the apposed palatal shelves. J. Cell. Biochem. 107: 818–825, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
864.
Kim KA  Park PW  Park JY 《Chirality》2009,21(5):485-491
Amlodipine is a racemic mixture composed of S- and R-form and metabolized stereoselectively. Cytochrome P450 3A (CYP3A) including CYP3A5 are involved in the metabolism of amlodipine and it was reported that polymorphic CYP3A5 genotype modulates the plasma levels of amlodipine and thus affect its pharmacokinetics. This study was conducted to find whether stereoselective pharmacokinetics of amlodipine was affected by the polymorphic CYP3A5 genotype. Seventeen healthy subjects were genotyped for CYP3A5*3 variant. After a single dose of 10-mg amlodipine, enantiomers of amlodipine were analyzed using HPLC-MS/MS equipped with an AGP column. Amlodipine showed stereoselective pharmacokinetics. S-amlodipine exhibited higher plasma levels than R-amlodipine in both genotype groups. S-amlodipine showed 15% higher mean peak plasma concentrations (Cmax) in CYP3A5*1/*3 carriers (3.28 ng/ml) than CYP3A5*3/*3 carriers (2.85 ng/ml) (P = 0.194) and R-amlodipine also showed 21% higher Cmax in CYP3A5*1/*3 carriers (3.33 ng/ml) than CYP3A5*3/*3 carriers (2.75 ng/ml) (P = 0.114). CYP3A5*1/*3 carriers also have 23 and 12% higher mean area under the time versus concentration curve of R-amlodipine and S-amlodipine than CYP3A5*3/*3 carriers, respectively (for R-amlodipine, 147.1 ng*h/ml for CYP3A5*1/*3 carriers versus 121.8 ng*h/ml for CYP3A5*3/*3 carriers, P = 0.234; for S-amlodipine, 161.6 ng*h/ml for CYP3A5*1/*3 carriers vs. 144.2 ng*h/ml for CYP3A5*3/*3 carriers, P = 0.353). Other pharmacokinetic parameters also showed no significant difference between them. In conclusion, the present study showed that despite the evidence that amlodipine is stereoselectively metabolized, CYP3A5*3 genotype did not affect stereoselective disposition of amlodipine. It provides the evidence that CYP3A5*3genotype plays a minor role in the interindividual variability of stereoselective disposition of amlodipine in humans.  相似文献   
865.
866.
To understand the factors that induce floral senescence in Hibiscus syriacus L., we have investigated the effects of various chemical agents on flower senescence at two different flowering stages, before and after full bloom, as well as the relationship between flower longevity and endogenous ethylene production before full bloom. Treatments with ethylene, 1-aminocyclopropane-1-carboxylic acid (ACC), and ethephon enhanced floral senescence, while aminoethoxyvinylglycine (AVG) promoted flower longevity regardless of treatment timing. Although ethanol slightly extended flower longevity, abscisic acid (ABA), nitric oxide, boric acid and sucrose, which have been reported to affect flower longevity or senescence, had no effect on H. syriacus floral senescence. The polyamine spermine (SPM), methylglyoxal-bis(guanylhydrazone) (MGBG), an inhibitor of SPM biosynthesis, and cycloheximide (CHI) accelerated flower senescence when applied before full bloom, but had no effect when applied after full bloom. SPM, MGBG and CHI treatments resulted in enhanced ethylene production during flower opening, and the promotion of flower senescence is mediated by ethylene production prior to full bloom. Furthermore, endogenous ethylene, spontaneously produced before blooming, was closely associated with floral senescence. These results suggest that ethylene production during flower opening plays a key role in determining the timing of Hibiscus flower senescence.  相似文献   
867.
The structural gene encoding bacterioferritin comigratory protein (Bcp) was amplified using PCR from the genomic DNA of Schizosaccharomyces pombe, and transferred into the shuttle vector pRS316 to generate the recombinant plasmid pBCPlO. The bcp + mRNA level in the pBCPlO-containing yeast cells was significantly higher than that in the control yeast cells, indicating that the cloned gene is functioning. The S. pombe cells harboring the plasmid pBCPIO exhibited higher survival on the solid minimal media with hydrogen peroxide, tert-BOOH or cadmium than the control yeast cells. They also exhibited enhanced cellular viability in the liquid media containing the stressful agents. The increased viabilities of the fission yeast cells harboring the plasmid pBCP10 were also obtained with 0.4% glucose or 0.4% sucrose as a sole carbon source, and nitrogen starvation, compared with those of the control yeast cells. The total glutathione (GSH) content and total GSH/GSSG ratio were significantly higher in the yeast cells harboring the plasmid pBCP10 than in the control yeast cells. In brief, the S. pombe Bcp plays a protective role in the defensive response to oxidative stress possibly via up-regulation of total and reduced glutathione levels.  相似文献   
868.
A strictly aerobic Gram-positive, moderately halophilic spore forming bacterium, designated strain SL6-1T, was isolated from a salt lake in Xin-jiang province, China. Growth of strain SL6-1T was observed at NaCl concentrations of 0∼20% (w/v) (the optimum being 5∼7%, w/v). The peptidoglycan type of strain SL6-1T was Alγ-meso-diaminopimelic acid and its major cellular fatty acids were iso-C14:0 and iso-C16:0 and ante-iso-C15:0. The major respiratory isoprenoid quinone was MK-7 and the G+C content of the genomic DNA was 44.5 mol%. The major cellular phospholipids were phosphatidylglycerol and diphosphatidylglycerol. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain SL6-1T formed a phylogenetic lineage within the genus Virgibacillus. Based on 16S rRNA gene sequence similarity, the strain was most closely related to Virgibacillus olivae E308T, Virgibacillus kekensis YIM kkny16T, Virgibacillus marismortui DSM 12325T with 97.1%, 97.1%, and 97.0% gene sequence similarities, respectively and the sequence similarities to other related taxa were less than 96.7%. The DNA relatedness values between strain SL6-1T and V. olivae E308T, V. kekensis YIM kkny16T, V. marismortui DSM 12325T were 16.7%, 51.0%, and 22.8%, respectively. On the basis of physiological, biochemical and phylogenetic properties, strain SL6-1T represents a novel species, for which the name Virgibacillus xinjiangensis sp. nov. is proposed. The type strain is SL6-1T (=KCTC 13128T =DSM 19031T).  相似文献   
869.
Pellet size of white rot fungus, Pleurotus ostreatus may affect the secretion of its degradative enzymes and accompanying biodegrading capability, but could be controlled by several physical culture conditions in liquid culture. The pellet size of P. ostreatus was affected by the volume of inoculum, flask, and medium, but the agitation speed was the most important control factor. At the lower agitation speed of 100 rpm, the large pellets were formed and the laccase activity was higher than that of small pelleted culture at 150 rpm, which might be due to loose intrapellet structure. However, the biodegradation rates of benzylbutylphthalate and dimethylphthalate were higher in the small pelleted culture, which indicated the involvement of other degradative enzyme rather than laccase. The activity of esterase which catalyzes the nonphenolic compounds before the reaction of ligninolytic enzymes was higher in the small pelleted culture, and coincided with the degradation pattern of phthalates. This study suggests the optimization of pellet morphology and subsequent secretion of degradative enzymes is necessary for the efficient removal of recalcitrants by white rot fungi.  相似文献   
870.
For the development of safer anti-inflammatory agents, simple aromatic compounds containing propenone moiety were prepared and evaluated for their dual COX/5-LOX inhibitory activities. Among the 17 prepared compounds, most of the compounds exhibited considerable COX/5-LOX inhibitory activities. Especially compound C(15) showed the most significant dual COX/5-LOX inhibitory activity.  相似文献   
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