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991.
Kang‐Young Choi Hyun‐Jung Kim Byung‐Chae Cho In‐San Kim Hyun‐Jung Kim Hyun‐Mo Ryoo 《Journal of cellular biochemistry》2009,107(4):818-825
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
992.
James Kempson Junqing Guo Jagabandhu Das Robert V. Moquin Steven H. Spergel Scott H. Watterson Charles M. Langevine Alaric J. Dyckman Mark Pattoli James R. Burke XiaoXia Yang Kathleen M. Gillooly Kim W. McIntyre Laishun Chen John H. Dodd Murray McKinnon Joel C. Barrish William J. Pitts 《Bioorganic & medicinal chemistry letters》2009,19(10):2646-2649
A new series of tricyclic-based inhibitors of IKK have been derived from an earlier lead compound. The synthesis and structure–activity relationships (SAR) are described. Compound 4k inhibited TNF production in rats stimulated with LPS. 相似文献
993.
Su Jin Kim Jeong Ah Lee Keehoon Won Yong Hwan Kim Bong Keun Song 《Process Biochemistry》2009,44(7):731-735
A Coprinus cinereus peroxidase (CiP) was successfully expressed by the methylotrophic yeast Pichia pastoris. The 1095-bp gene encoding peroxidase from C. cinereus was cloned with a highly inducible alcohol oxidase (AOX1) promoter and integrated into the genome of P. pastoris. The recombinant CiP (rCiP) fused with the α-mating factor pre-pro leader sequence derived from Saccharomyces cerevisiae accumulated neither inside the cell nor within the wall, and were efficiently secreted into the culture medium. SDS-PAGE and immunoblot analysis revealed that the rCiP was not hyper-glycosylated and its α-factor signal sequence was correctly processed. It was also found that the kinetic properties of rCiP were similar to those of native CiP. In order to produce large amounts of rCiP, the high cell density cultivation of recombinant P. pastoris was carried out in a fermentor with fed-batch mode. The peroxidase activity obtained in a 5 l fermentor cultivation became about 6 times (1200 U/ml) higher than that in shake-flask cultures (200 U/ml). 相似文献
994.
Caroline B. Milne Pan-Jun Kim James A. Eddy Nathan D. Price Dr. 《Biotechnology journal》2009,4(12):1653-1670
Driven by advancements in high-throughput biological technologies and the growing number of sequenced genomes, the construction of in silico models at the genome scale has provided powerful tools to investigate a vast array of biological systems and applications. Here, we review comprehensively the uses of such models in industrial and medical biotechnology, including biofuel generation, food production, and drug development. While the use of in silico models is still in its early stages for delivering to industry, significant initial successes have been achieved. For the cases presented here, genome-scale models predict engineering strategies to enhance properties of interest in an organism or to inhibit harmful mechanisms of pathogens. Going forward, genome-scale in silico models promise to extend their application and analysis scope to become a transformative tool in biotechnology. 相似文献
995.
H.S. Jun In K. Kim H.J. Lee H.J. Lee Jae H. Kang J.R. Kim Hyoung D. Shin J. Song 《Obesity (Silver Spring, Md.)》2009,17(2):355-362
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
996.
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
997.
998.
999.
Follicles are important in oocyte maturation. Successful estrous cycle requires remodeling of follicular cells, and proper execution of programmed cell death is crucial for normal follicular development. The objectives of the present study were to understand programmed cell death during follicle development, to analyze the differential follicle development patterns, and to assess the patterns of apoptosis and autophagy expression during follicle development in normal and miniature pigs. Through the analysis of differential patterns of programmed cell death during follicular development in porcine, MAP1LC3A, B and other autophagy-associated genes (ATG5, mTOR, Beclin-1) were found to increase in normal pigs, while it decreased in miniature pigs. However, for the apoptosis-associated genes, progression of genes during follicular development increased in miniature pigs, while it decreased in normal pigs. Thus, results show that normal and miniature pigs showed distinct patterns of follicular remodeling manifesting that programmed cell death largely depends on the types of pathway during follicular development (Type II or autophagy for normal pigs and Type I or apoptosis for miniature pigs). 相似文献
1000.
Choonkeun Kim Catarina Milheiri?o Susana Gardete Mark A. Holmes Matt T. G. Holden Hermínia de Lencastre Alexander Tomasz 《The Journal of biological chemistry》2012,287(44):36854-36863
Methicillin-resistant Staphylococcus aureus (MRSA) strains show strain-to-strain variation in resistance level, in genetic background, and also in the structure of the chromosomal cassette (SCCmec) that carries the resistance gene mecA. In contrast, strain-to-strain variation in the sequence of the mecA determinant was found to be much more limited among MRSA isolates examined so far. The first exception to this came with the recent identification of MRSA strain LGA251, which carries a new homolog of this gene together with regulatory elements mecI/mecR that also have novel, highly divergent structures. After cloning and purification in Escherichia coli, PBP2ALGA, the protein product of the new mecA homolog, showed aberrant mobility in SDS-PAGE, structural instability and loss of activity at 37 °C, and a higher relative affinity for oxacillin as compared with cefoxitin. The mecA homolog free of its regulatory elements was cloned into a plasmid and introduced into the background of the β-lactam-susceptible S. aureus strain COL-S. In this background, the mecA homolog expressed a high-level resistance to cefoxitin (MIC = 400 μg/ml) and a somewhat lower resistance to oxacillin (minimal inhibitory concentration = 200 μg/ml). Similar to PBP2A, the protein homolog PBP2ALGA was able to replace the essential function of the S. aureus PBP2 for growth. In contrast to PBP2A, PBP2ALGA did not depend on the transglycosylase activity of the native PBP2 for expression of high level resistance to oxacillin, suggesting that the PBP2A homolog may preferentially cooperate with a monofunctional transglycosylase as the alternative source of transglycosylase activity. 相似文献