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41.
A large set of mutants of CYP102A1 from Bacillus megaterium have human cytochrome P450-like activities and the ability to metabolize a number of marketed drugs and steroids. Here, we tested whether the CYP102A1 mutants could be used to produce hydroxylated human metabolites of 17β-estradiol (E2). A set of the mutants, which were generated by site-directed and random mutagenesis, was used to produce hydroxylated human metabolites of E2 in this study. Some of the tested mutants could regioselectively generate 2-OH E2 as a major metabolite but not other hydroxylated products. These results suggest that CYP102A1 mutants would be useful for the bioconversion of steroid hormones to hydroxylated products, which can be used for industrial applications. 相似文献
42.
Young Jin Ryu Seung Hong Choi Sang Joon Park Tae Jin Yun Ji-Hoon Kim Chul-Ho Sohn 《PloS one》2014,9(9)
Background and Purpose
To apply a texture analysis of apparent diffusion coefficient (ADC) maps to evaluate glioma heterogeneity, which was correlated with tumor grade.Materials and Methods
Forty patients with glioma (WHO grade II (n = 8), grade III (n = 10) and grade IV (n = 22)) underwent diffusion-weighted imaging (DWI), and the corresponding ADC maps were obtained. Regions of interest containing the lesions were drawn on every section of the ADC map containing the tumor, and volume-based data of the entire tumor were constructed. Texture and first order features including entropy, skewness and kurtosis were derived from the ADC map using in-house software. A histogram analysis of the ADC map was also performed. The texture and histogram parameters were compared between low-grade and high-grade gliomas using an unpaired student’s t-test. Additionally, a one-way analysis of variance analysis with a post-hoc test was performed to compare the parameters of each grade.Results
Entropy was observed to be significantly higher in high-grade gliomas than low-grade tumors (6.861±0.539 vs. 6.261±0.412, P = 0.006). The fifth percentiles of the ADC cumulative histogram also showed a significant difference between high and low grade gliomas (836±235 vs. 1030±185, P = 0.037). Only entropy proved to be significantly different between grades III and IV (6.295±0.4963 vs. 7.119±0.3165, P<0.001). The diagnostic accuracy of ADC entropy was significantly higher than that of the fifth percentile of the ADC histogram (P = 0.0034) in distinguishing high- from low-grade glioma.Conclusion
A texture analysis of the ADC map based on the entire tumor volume can be useful for evaluating glioma grade, which provides tumor heterogeneity. 相似文献43.
Jae Hyun Kim Seung Hong Choi Inseon Ryoo Tae Jin Yun Tae Min Kim Se-Hoon Lee Chul-Kee Park Ji-Hoon Kim Chul-Ho Sohn Sung-Hye Park Il Han Kim 《PloS one》2014,9(11)
Purpose
To assess the prognosis predictability of a measurable enhancing lesion using histogram parameters produced by the normalized cerebral blood volume (nCBV) and normalized apparent diffusion coefficient (nADC) after completion of standard concomitant chemoradiotherapy (CCRT) and adjuvant temozolomide (TMZ) medication in glioblastoma multiforme (GBM) patients.Materials and Methods
This study was approved by the institutional review board (IRB), and the requirement for informed consent was waived. A total of 59 patients with newly diagnosed GBM who received standard CCRT with TMZ and adjuvant TMZ for six cycles underwent perfusion-weighted and diffusion-weighted imaging. Twenty-seven patients had a measurable enhancing lesion and 32 patients lacked a measurable enhancing lesion based on the Response Assessment in Neuro-Oncology (RANO) criteria in the follow-up MRI, which was performed within 3 months after adjuvant TMZ therapy was completed. We measured the nCBV and nADC histogram parameters based on the measurable enhancing lesion. The progression free survival (PFS) was analyzed by the Kaplan-Meier method with the use of the log-rank test.Results
The median PFS of patients lacking measurable enhancing lesion was longer than for those with measurable enhancing lesions (17.6 vs 3.3 months, P<.0001). There was a significant, positive correlation between the 99th percentile nCBV value of a measurable enhancing lesion and the PFS (P = .044, R2 = .152). In addition, the median PFS was longer in patients with a 99th percentile nCBV value ≧4.5 than it was in those with a value <4.5 (4.4 vs 3.1 months, P = .036).Conclusion
We found that the nCBV value can be used for the prognosis prediction of a measurable enhancing lesion after the completion of standard treatment for GBM, wherein a high 99th percentile nCBV value (≧4.5) suggests a better PFS for GBM patients. 相似文献44.
The use of cytochrome P450 (P450 or CYP) enzymes as biocatalysts for the production of fine chemicals, including pharmaceuticals, has been of increasing interest, primarily owing to their catalytic diversity and broad substrate range. CYP102A1 (P450 BM3) from Bacillus megaterium integrates an entire monooxygenase system into one polypeptide and represents an appropriate prokaryotic model for industrial applications of mammalian P450 activities. CYP102A1 not only exhibits the highest catalytic activity ever detected in a P450 monooxygenase but also provides a potentially versatile biocatalyst for the production of human P450 metabolites. CYP102A1 can be further engineered to be a drug-metabolizing enzyme, making it a promising candidate to use as a biocatalyst in drug discovery and synthesis. 相似文献
45.
Sung-Young Lee Andy T. Y. Lau Chul-Ho Jeong Jung-Hyun Shim Hong-Gyum Kim Jaebong Kim Ann M. Bode Zigang Dong 《The Journal of biological chemistry》2010,285(38):29525-29534
A role for histone H2AX, one of the variants of the nucleosome core histone H2A, has been demonstrated in DNA repair, tumor suppression, apoptosis, and cell cycle checkpoint function. However, the physiological function and post-translational modification of histone H2AX during vertebrate development have not been elucidated. Here, we provide evidence showing that Xenopus histone H2AX (XH2AX) has a role in the anterior neural plate for eye field formation during Xenopus embryogenesis. A loss-of-function study clearly demonstrated a critical role of XH2AX in anterior neural specification. Through a differentiation assay with Xenopus animal cap embryonic stem cells, we confirmed that XH2AX is required for the activin-induced anterior neural specification of the ectoderm. Furthermore, we found that Chk1 is an essential kinase to phosphorylate histone XH2AX at Thr16, which is involved in the biological function of this histone. Taken together, our findings reveal that XH2AX has a specific role in anterior neural formation of Xenopus, which is mediated through phosphorylation of XH2AX at Thr16 by Chk1. 相似文献
46.
Lee CH Kim EH Won YS Choi YK Nam KH Kim HC Hyun BH Suh JG Oh YS 《Biochemical genetics》2005,43(11-12):597-602
A new electrophoretic migration type of alkaline phosphatase 1 (Akp1) was found on the cellulose acetate electrophoresis for kidney and liver homogenates of KWHM mouse, a newly established inbred strain derived from the Korean wild mouse (Mus musculus molossinus). This new type of alkaline phosphatase 1 was distinguished from previously reported AKP1A and AKP1B types in the mouse, and tentatively named AKP1C. In genetic analysis by mating experiments between KWHM and C57BL/6J (AKP1A) or BALB/cA (AKP1B), the phenotypic segregation ratios of AKP1A : AKP1AC : AKP1C or AKP1B : AKP1BC : AKP1C were 1 : 2 : 1 in both groups of F2 generations. It was therefore concluded that AKP1C type is controlled by Akp1c allele which is codominant with Akp1a and Akp1b alleles. 相似文献
47.
Trehalose added to storage buffers for chemical-induced transformations at 200 mm increased the survival of Escherichia coli competent cells 1.34.8-fold over 180 d cryostorage compared with dimethyl sulfoxide or glycerol. 相似文献
48.
Young-Suk Won Eui-Suk Jeong Hyun-Ji Park Chul-Ho Lee Ki-Hoan Nam Hyoung-Chin Kim Jong-Im Park Yang-Kyu Choi 《Experimental Animals》2007,56(2):85-91
Corynebacterium (C) kutscheri and Staphylococcus aureus were isolated from two Sprague-Dawley (SD) rats with a hemisected spinal cord. Grossly, gray-white bulging foci and abscesses were distributed throughout the parenchyma of the lung. Pathologically, severe necrotizing lobar pneumonia with abscesses and fibrinous pleuritis were observed. Immunohistochemical analysis found accumulation of galectin-3 in alveolar macrophages and the alveolar interstitial region. No other viral or bacterial pathogens were detected in these animals. In addition, similar pathogenic changes and accumulation of galectin-3 were observed in the lungs of SD rats experimentally infected with C. kutscheri. Using northern blot analysis, the relative galectin-3 and GAPDH mRNA levels were 4.6 to 9.3 times higher in C. kutscheri-infected lung than in uninfected controls. These results demonstrate that a single C. kutscheri infection can induce the upregulation of galectin-3 in the lung and that this molecule may have an important pathogenic role in C. kutscheri infections in rats. 相似文献
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50.
Myoung Seok Ko Ji Young Yun In-Jeoung Baek Jung Eun Jang Jung Jin Hwang Seung Eun Lee Seung-Ho Heo David A. Bader Chul-Ho Lee Jaeseok Han Jong-Seok Moon Jae Man Lee Eun-Gyoung Hong In-Kyu Lee Seong Who Kim Joong Yeol Park Sean M. Hartig Un Jung Kang David D. Moore Eun Hee Koh Ki-up Lee 《Autophagy》2021,17(5):1205