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41.
42.
Biallelic Mutations in FUT8 Cause a Congenital Disorder of Glycosylation with Defective Fucosylation
43.
Purification and characterization of charantin, a napin-like ribosome-inactivating peptide from bitter gourd (Momordica charantia) seeds. 总被引:3,自引:0,他引:3
A peptide designated charantin, with a molecular mass of 9.7 kDa, was isolated from bitter gourd seeds. The procedure comprised affinity chromatography on Affi-gel blue gel, ion-exchange chromatography on Mono S and gel filtration on Superdex 75. The N-terminal sequence of charantin exhibited marked similarity to that of the 7.8-kDa napin-like peptide previously isolated from bitter gourd seeds. Charantin inhibited cell-free translation in a rabbit reticulocyte lysate system with an IC50 of 400 nm, a potency lower than that of the previously reported small ribosome-inactivating protein gamma-momorcharin (IC50 = 55 nm) which also exhibited an abundance of arginine and glutamate/glutamine residues. Charantin reacted positively in the N-glycosidase assay, yielding a band similar to that formed by the small ribosome-inactivating proteins gamma-momorcharin and luffin S. 相似文献
44.
45.
Cheuk-Yiu Law Chung-Wah Siu Katherine Fan Wing-Hon Lai Ka-Wing Au Yee-Man Lau Lai-Yung Wong Jenny C.Y. Ho Yee-ki Lee Hung-Fat Tse Kwong-Man Ng 《Biochemistry and Biophysics Reports》2016
Patients with Danon disease may suffer from severe cardiomyopathy, skeletal muscle dysfunction as well as varying degrees of mental retardation, in which the primary deficiency of lysosomal membrane-associated protein-2 (LAMP2) is considerably associated. Owing to the scarcity of human neurons, the pathological role of LAMP2 deficiency in neural injury of humans remains largely elusive. However, the application of induced pluripotent stem cells (iPSCs) may shed light on overcoming such scarcity.In this study, we obtained iPSCs derived from a patient carrying a mutated LAMP2 gene that is associated with Danon disease. By differentiating such LAMP2-deficient iPSCs into cerebral cortical neurons and with the aid of various biochemical assays, we demonstrated that the LAMP2-deficient neurons are more susceptible to mild oxidative stress-induced injury.The data from MTT assay and apoptotic analysis demonstrated that there was no notable difference in cellular viability between the normal and LAMP2-deficient neurons under non-stressed condition. When exposed to mild oxidative stress (10 μM H2O2), the LAMP2-deficient neurons exhibited a significant increase in apoptosis. Surprisingly, we did not observe any aberrant accumulation of autophagic materials in the LAMP2-deficient neurons under such stress condition.Our results from cellular fractionation and inhibitor blockade experiments further revealed that oxidative stress-induced apoptosis in the LAMP2-deficient cortical neurons was caused by increased abundance of cytosolic cathepsin L. These results suggest the involvement of lysosomal membrane permeabilization in the LAMP2 deficiency associated neural injury. 相似文献
46.
David Charles Boettiger Stephen Kerr Rossana Ditangco Tuti Parwati Merati Thuy Thi Thanh Pham Romanee Chaiwarith Sasisopin Kiertiburanakul Chung Ki Patrick Li Nagalingeswaran Kumarasamy Saphonn Vonthanak Christopher Lee Nguyen Van Kinh Sanjay Pujari Wing Wai Wong Adeeba Kamarulzaman Fujie Zhang Evy Yunihastuti Jun Yong Choi Shinichi Oka Oon Tek Ng Pacharee Kantipong Mahiran Mustafa Winai Ratanasuwan Annette Sohn Matthew Law 《PloS one》2014,9(9)
Background
Antiretroviral therapy (ART) has evolved rapidly since its beginnings. This analysis describes trends in first-line ART use in Asia and their impact on treatment outcomes.Methods
Patients in the TREAT Asia HIV Observational Database receiving first-line ART for ≥6 months were included. Predictors of treatment failure and treatment modification were assessed.Results
Data from 4662 eligible patients was analysed. Patients started ART in 2003–2006 (n = 1419), 2007–2010 (n = 2690) and 2011–2013 (n = 553). During the observation period, tenofovir, zidovudine and abacavir use largely replaced stavudine. Stavudine was prescribed to 5.8% of ART starters in 2012/13. Efavirenz use increased at the expense of nevirapine, although both continue to be used extensively (47.5% and 34.5% of patients in 2012/13, respectively). Protease inhibitor use dropped after 2004. The rate of treatment failure or modification declined over time (22.1 [95%CI 20.7–23.5] events per 100 patient/years in 2003–2006, 15.8 [14.9–16.8] in 2007–2010, and 11.6 [9.4–14.2] in 2011–2013). Adjustment for ART regimen had little impact on the temporal decline in treatment failure rates but substantially attenuated the temporal decline in rates of modification due to adverse event. In the final multivariate model, treatment modification due to adverse event was significantly predicted by earlier period of ART initiation (hazard ratio 0.52 [95%CI 0.33–0.81], p = 0.004 for 2011–2013 versus 2003–2006), older age (1.56 [1.19–2.04], p = 0.001 for ≥50 years versus <30years), female sex (1.29 [1.11–1.50], p = 0.001 versus male), positive hepatitis C status (1.33 [1.06–1.66], p = 0.013 versus negative), and ART regimen (11.36 [6.28–20.54], p<0.001 for stavudine-based regimens versus tenofovir-based).Conclusions
The observed trends in first-line ART use in Asia reflect changes in drug availability, global treatment recommendations and prescriber preferences over the past decade. These changes have contributed to a declining rate of treatment modification due to adverse event, but not to reductions in treatment failure. 相似文献47.
Yang Shih-Jyun Ng Chau-Yee Wu Ting-Shu Huang Po-Yen Wu Yen-Mu Sun Pei-Lun 《Mycopathologia》2019,184(1):169-176
Mycopathologia - Phaeohyphomycosis is a term used to describe a heterogenous group of cutaneous and systemic mycotic infections caused by melanized fungi. Many fungi have been reported as pathogens... 相似文献
48.
Modeling recurrent DNA copy number alterations in array CGH data 总被引:1,自引:0,他引:1
MOTIVATION: Recurrent DNA copy number alterations (CNA) measured with array comparative genomic hybridization (aCGH) reveal important molecular features of human genetics and disease. Studying aCGH profiles from a phenotypic group of individuals can determine important recurrent CNA patterns that suggest a strong correlation to the phenotype. Computational approaches to detecting recurrent CNAs from a set of aCGH experiments have typically relied on discretizing the noisy log ratios and subsequently inferring patterns. We demonstrate that this can have the effect of filtering out important signals present in the raw data. In this article we develop statistical models that jointly infer CNA patterns and the discrete labels by borrowing statistical strength across samples. RESULTS: We propose extending single sample aCGH HMMs to the multiple sample case in order to infer shared CNAs. We model recurrent CNAs as a profile encoded by a master sequence of states that generates the samples. We show how to improve on two basic models by performing joint inference of the discrete labels and providing sparsity in the output. We demonstrate on synthetic ground truth data and real data from lung cancer cell lines how these two important features of our model improve results over baseline models. We include standard quantitative metrics and a qualitative assessment on which to base our conclusions. AVAILABILITY: http://www.cs.ubc.ca/~sshah/acgh. 相似文献
49.
Repeated Biogel P6 chromatography of the urine from a patient with fucosidosis yielded several fractions containing fucosyloligosaccharides and glycopeptides. Two of these were shown by 1H nuclear magnetic resonance (1H-n.m.r.) spectroscopy and permethylation analysis to have the following structures respectively: (I) αfuc (1→3) [βgal (1→4)] βglcNAc (1→2) αman () βman (1→4) glcNAc and (II) αfuc (1→3) [βgal (1→4)] βglcNAc (1→2) αman () βman (1→4) βglcNAc (1→4) [αfuc ()] βglcNAc-Asn. 相似文献
50.
Qingxin Li Ying Lei Wong Hui Qi Ng Shovanlal Gayen CongBao Kang 《Journal of peptide science》2014,20(12):935-944
The hERG (human ether‐a‐go‐go related gene) potassium channel is a voltage‐gated potassium channel containing an N‐terminal domain, a voltage‐sensor domain, a pore domain and a C‐terminal domain. The transmembrane segment 4 (S4) is important for sensing changes of membrane potentials through positively charge residues. A construct containing partial S2–S3 linker, S3, S4 and the S4–S5 linker of the hERG channel was purified into detergent micelles. This construct exhibits good quality NMR spectrum when it was purified in lyso‐myristoyl phosphatidylglycerol (LMPG) micelles. Structural study showed that S3 contains two short helices with a negatively charged surface. The S4 and S4–S5 linker adopt helical structures. The six positively charged residues in S4 localize at different sides, suggesting that they may have different functions in channel gating. Relaxation studies indicated that S3 is more flexible than S4. The boundaries of S3–S4 and S4–S4–S5 linker were identified. Our results provided structural information of the S3 and S4, which will be helpful to understand their roles in channel gating. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd. 相似文献