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881.
Jae Su Kim Se Jin Lee Margaret Skinner Bruce L. Parker Byung-Taek Oh Kui-Jae Lee 《BioControl》2013,58(5):607-614
Bioassay can be used for analysis of the biological potency of Bacillus thuringiensis (Bt) in fermentation and formulation but requires precise scheduling and several repetitions. Alternatively, this work explored if the endospore counting could be used to predict the potency of Bt technical powder. Analyses of Bt technical powers provided a strong linear relationship (r = 0.971) between the number of viable endospores and the potency of the technical powder against second instar Plutella xylostella (L.) larvae. Next, a Bt wettable powder formulation was stored at 25 and 40 °C for 12 weeks to investigate the influence of storage temperature on the prediction of insecticidal potency based on the counting. At 25 °C storage, the insecticidal potency could be predicted based on the counting, but at 40 °C the predicted insecticidal potency was much lower than the measured potency. These results suggest that the NT0423 endospore viability can be used to predict its potency in production, but the relationship may not be the same following the storage at high temperature. 相似文献
882.
In eukaryotic cells consisting of many different types of organelles, targeting of organellar proteins is one of the most fundamental cellular processes. Proteins belonging to the endoplasmic reticulum (ER), chloroplasts and mitochondria are targeted individually from the cytosol to their cognate organelles. As the targeting to these organelles occurs in the cytosol during or after translation, the most crucial aspect is how specific targeting to these three organelles can be achieved without interfering with other targeting pathways. For these organelles, multiple mechanisms are used for targeting proteins, but the exact mechanism used depends on the type of protein and organelle, the location of targeting signals in the protein and the location of the protein in the organelle. In this review, we discuss the various mechanisms involved in protein targeting to the ER, chloroplasts and mitochondria, and how the targeting specificity is determined for these organelles in plant cells . 相似文献
883.
The hyperthermophilic endocellulase, EGPh (glycosyl hydrolase family 5) from Pyrococcus horikoshii possesses 4 cysteine residues forming 2 disulfide bonds, as identified by structural analysis. One of the disulfide bonds is located at the proximal region of the active site in EGPh, which exhibits a distinct pattern from that of the thermophilic endocellulase EGAc (glycosyl hydrolase family 5) of Acidothermus cellulolyticus despite the structural similarity between the two endocellulases. The structural similarity between EGPh and EGAc suggests that EGPh possesses a structure suitable for changing the position of the disulfide bond corresponding to that in EGAc. Introduction of this alternative disulfide bond in EGPh, while removing the original disulfide bond, did not result in a loss of enzymatic activity but the EGPh was no longer hyperthermostable. These results suggest that the contribution of disulfide bond to hyperthermostability at temperature higher than 100 °C is restrictive, and that its impact is dependent on the specific structural environment of the hyperthermophilic proteins. The data suggest that the structural position and environment of the disulfide bond has a greater effect on high-temperature thermostability of the enzyme than on the potential energy of the dihedral angle that contributes to disulfide bond cleavage. 相似文献
884.
885.
Ji Hyun Kim In Su Park Yongdoo Park Youngmee Jung Soo Hyun Kim Sang-Heon Kim 《Cytotherapy》2013,15(5):542-556
Background aimsTo successfully treat myocardial infarction (MI), blood must be resupplied to the ischemic myocardium by inducing angiogenesis. Many studies report enhanced angiogenesis using stem cells; however, the therapeutic efficacy of cell transplant remains low because transplanted cells may not survive, be retained at the site of transplant, or develop into vascular tissue. In this study, we assessed the therapeutic potential of three-dimensional cell masses (3DCM) composed of human adipose-derived stem cells (hASC) in a rat MI model.MethodsFor formation of 3DCM, hASC were cultured on a substrate with immobilized fibroblast growth factor 2. The morphology and phenotypes of 3DCM were analyzed 1 day after culture. The cells (hASC and 3DCM, 5 × 105 cells) were injected into ischemic regions after ligation of the left coronary artery (n = 6 in each group). Cell retention ratio, therapeutic efficacy and vascularization were evaluated 4 weeks after transplant.ResultsA spheroid-type 3DCM, which included vascular cells (CD34+/CD31+/KDR+/α-SMA+) with high production of human vascular endothelial growth factor, was obtained. Infarct size and cardiomyocyte apoptosis were reduced in the 3DCM-injected group compared with the hASC-injected group. The retention ratio of hASC was 14-fold higher in the 3DCM-injected group. Many transplanted cells differentiated into endothelial and smooth muscle cells and formed vascular networks incorporated into host vessels.ConclusionsTransplant of 3DCM may be useful for angiogenic cell therapy to treat MI. 相似文献
886.
Sangwoo Kim Kyowon Jeong Kunal Bhutani Jeong Ho Lee Anand Patel Eric Scott Hojung Nam Hayan Lee Joseph G Gleeson Vineet Bafna 《Genome biology》2013,14(8):R90
Detection of somatic variation using sequence from disease-control matched data sets is a critical first step. In many cases including cancer, however, it is hard to isolate pure disease tissue, and the impurity hinders accurate mutation analysis by disrupting overall allele frequencies. Here, we propose a new method, Virmid, that explicitly determines the level of impurity in the sample, and uses it for improved detection of somatic variation. Extensive tests on simulated and real sequencing data from breast cancer and hemimegalencephaly demonstrate the power of our model. A software implementation of our method is available at http://sourceforge.net/projects/virmid/. 相似文献
887.
Janet Lee Jeong-Hwa Baek Kyu-Sil Choi Hyun-Soo Kim Hye-Young Park Geun-Hyoung Ha Ho Park Kyo-Won Lee Chang Geun Lee Dong-Yun Yang Hyo Eun Moon Sun Ha Paek Chang-Woo Lee 《Cell cycle (Georgetown, Tex.)》2013,12(3):442-451
Multipotent mesenchymal stem/stromal cells (MSCs) are capable of differentiating into a variety of cell types from different germ layers. However, the molecular and biochemical mechanisms underlying the transdifferentiation of MSCs into specific cell types still need to be elucidated. In this study, we unexpectedly found that treatment of human adipose- and bone marrow-derived MSCs with cyclin-dependent kinase (CDK) inhibitor, in particular CDK4 inhibitor, selectively led to transdifferentiation into neural cells with a high frequency. Specifically, targeted inhibition of CDK4 expression using recombinant adenovial shRNA induced the neural transdifferentiation of human MSCs. However, the inhibition of CDK4 activity attenuated the syngenic differentiation of human adipose-derived MSCs. Importantly, the forced regulation of CDK4 activity showed reciprocal reversibility between neural differentiation and dedifferentiation of human MSCs. Together, these results provide novel molecular evidence underlying the neural transdifferentiation of human MSCs; in addition, CDK4 signaling appears to act as a molecular switch from syngenic differentiation to neural transdifferentiation of human MSCs. 相似文献
888.
Jun Seo Goo Yo Na Kim Kyung Mi Choi In Sik Hwang Ji Eun Kim Young Ju Lee Moon Hwa Kwak Sun Bo Shim Seung Wan Jee Chul Joo Lim Je Kyung Seong Dae Youn Hwang 《Clinical proteomics》2013,10(1):10
Background
To characterize changes in global protein expression in kidneys of transgenic rats overexpressing human selenoprotein M (SelM) in response to increased bioabivility of selenium (Sel), total proteins extracted from kidneys of 10-week-old CMV/hSelM Tg and wild-type rats were separated by 2-dimensional gel electrophoresis and measured for changes in expression.Results
Ten and three proteins showing high antioxidant enzymatic activity were up- and down-regulated, respectively, in SelM-overexpressing CMV/hSelM Tg rats compared to controls based on an arbitrary 2-fold difference. Up-regulated proteins included LAP3, BAIAP2L1, CRP2, CD73 antigen, PDGF D, KIAA143 homolog, PRPPS-AP2, ZFP313, HSP-60, and N-WASP, whereas down-regulated proteins included ALKDH3, rMCP-3, and STC-1. After Sel treatment, five of the up-regulated proteins were significantly increased in expression in wild-type rats, whereas there were no changes in CMV/hSelM Tg rats. Only two of the down-regulated proteins showed reduced expression in wild-type and Tg rats after Sel treatment.Conclusions
These results show the primary novel biological evidences that new functional protein groups and individual proteins in kidneys of Tg rats relate to Sel biology including the response to Sel treatment and SelM expression. 相似文献889.
Yuelian Sun Kim Overvad Wei Jin Zhou Jin Liang Zhu Jørn Olsen 《Birth defects research. Part B, Developmental and reproductive toxicology》2013,98(2):154-163
Cancer risk in parents may be related to congenital malformations (CMs) in their children if they share genetic susceptibility or environmental exposure that may be teratogenic and carcinogenic. We conducted a population‐based cohort study based on Danish register data. We identified 795,607 mothers and 781,424 fathers who had all their children between 1977 and 2007 in Denmark. Information on CM was obtained from the Danish Hospital Registry and information on cancer was obtained from the Danish Cancer Registry. Parents were followed from the birth of their first child until the diagnosis of cancer, death, emigration, or December 31, 2007. We used Cox regression models to estimate hazard ratios (HRs) for cancer including cancer in specific organs in mothers and fathers. Overall, 75,701 (9.5%) mothers and 72,724 (9.3%) fathers had at least one child diagnosed with CMs within the first year of life. Neither mothers (HR = 1.04; 95% CI: 0.99–1.04) nor fathers (HR = 1.03; 95% CI: 0.98–1.09) who had a child with a CM had a higher overall risk of cancer. Mothers (HR = 0.76, 95% CI: 0.58–1.00) or fathers (HR = 0.89, 95% CI: 0.66–1.19) who had a child with a chromosomal malformation had a lower overall cancer risk. The findings also showed a higher risk for some specific types of cancer in parents who had children with a CM in the specific system. Some, or perhaps all, of these findings may be due to chance caused by multiple comparisons. We present all results on paper or online to provide clues for further research and to avoid publication bias. 相似文献
890.
Eun-Young Won Mi-Kyung Yoon Sang-Woo Kim Youngae Jung Hyun-Whee Bae Daeyoup Lee Sung Goo Park Chul-Ho Lee Geum-Sook Hwang Seung-Wook Chi 《PloS one》2013,8(10)
Despite the numerous metabolic studies on obesity, gender bias in obesity has rarely been investigated. Here, we report the metabolomic analysis of obesity by using leptin-deficient ob/ob mice based on the gender. Metabolomic analyses of urine and serum from ob/ob mice compared with those from C57BL/6J lean mice, based on the 1H NMR spectroscopy in combination with multivariate statistical analysis, revealed clear metabolic differences between obese and lean mice. We also identified 48 urine and 22 serum metabolites that were statistically significantly altered in obese mice compared to lean controls. These metabolites are involved in amino acid metabolism (leucine, alanine, ariginine, lysine, and methionine), tricarbocylic acid cycle and glucose metabolism (pyruvate, citrate, glycolate, acetoacetate, and acetone), lipid metabolism (cholesterol and carnitine), creatine metabolism (creatine and creatinine), and gut-microbiome-derived metabolism (choline, TMAO, hippurate, p-cresol, isobutyrate, 2-hydroxyisobutyrate, methylamine, and trigonelline). Notably, our metabolomic studies showed distinct gender variations. The obese male mice metabolism was specifically associated with insulin signaling, whereas the obese female mice metabolism was associated with lipid metabolism. Taken together, our study identifies the biomarker signature for obesity in ob/ob mice and provides biochemical insights into the metabolic alteration in obesity based on gender. 相似文献