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121.
David F. Stowe Ashish K. Gadicherla Yifan Zhou Mohammed Aldakkak Qunli Cheng Wai-Meng Kwok Ming Tao Jiang James S. Heisner MeiYing Yang Amadou K.S. Camara 《生物化学与生物物理学报:生物膜》2013,1828(2):427-442
We tested if small conductance, Ca2 +‐sensitive K+ channels (SKCa) precondition hearts against ischemia reperfusion (IR) injury by improving mitochondrial (m) bioenergetics, if O2‐derived free radicals are required to initiate protection via SKCa channels, and, importantly, if SKCa channels are present in cardiac cell inner mitochondrial membrane (IMM). NADH and FAD, superoxide (O2?), and m[Ca2 +] were measured in guinea pig isolated hearts by fluorescence spectrophotometry. SKCa and IKCa channel opener DCEBIO (DCEB) was given for 10 min and ended 20 min before IR. Either TBAP, a dismutator of O2?, NS8593, an antagonist of SKCa isoforms, or other KCa and KATP channel antagonists, were given before DCEB and before ischemia. DCEB treatment resulted in a 2-fold increase in LV pressure on reperfusion and a 2.5 fold decrease in infarct size vs. non-treated hearts associated with reduced O2? and m[Ca2 +], and more normalized NADH and FAD during IR. Only NS8593 and TBAP antagonized protection by DCEB. Localization of SKCa channels to mitochondria and IMM was evidenced by a) identification of purified mSKCa protein by Western blotting, immuno-histochemical staining, confocal microscopy, and immuno-gold electron microscopy, b) 2-D gel electrophoresis and mass spectroscopy of IMM protein, c) [Ca2 +]‐dependence of mSKCa channels in planar lipid bilayers, and d) matrix K+ influx induced by DCEB and blocked by SKCa antagonist UCL1684. This study shows that 1) SKCa channels are located and functional in IMM, 2) mSKCa channel opening by DCEB leads to protection that is O2? dependent, and 3) protection by DCEB is evident beginning during ischemia. 相似文献
122.
Adel Shalata Maria C. Ramirez Robert J. Desnick Nolan Priedigkeit Christoph Buettner Claudia Lindtner Mohammed Mahroum Muhammad Abdul-Ghani Feng Dong Nazik Arar Olga Camacho-Vanegas Rui Zhang Sandra C. Camacho Ying Chen Mwafaq Ibdah Ralph DeFronzo Virginia Gillespie Kevin Kelley Brian D. Dynlacht Sehyun Kim Marc J. Glucksman Zvi U. Borochowitz John A. Martignetti 《American journal of human genetics》2013
123.
Rana Dajani Raja Fathallah Ala Arafat Mohammed Emad AbdulQader Nancy Hakooz Yousef Al-Motassem Mohammad El-Khateeb 《Biochemical genetics》2013,51(9-10):780-788
Methylenetetrahydrofolate reductase (MTHFR) C677T single nucleotide polymorphism is a major inherited risk factor of venous thromboembolism. We sought to determine its prevalence in genetically isolated populations of Chechens and Circassians in Jordan. The MTHFR C677T mutation was analyzed from blood samples taken from 120 random unrelated Chechens and 72 Circassians. The prevalence of the MTHFR mutation in the Chechen population was 27.5% (allele frequency 15%); the prevalence among the Circassians was 50% (allele frequency 29.2%). The prevalence in the Chechen population is similar to that in Jordan and other world populations, but it is higher in the Circassian population. This study will contribute to understanding the interaction between genetic and environmental risk factors underlying thrombosis and will be useful in deciding which genetic variants should be tested in a clinical genetic testing service. 相似文献
124.
Mika Zagrobelny Mohammed Saddik Motawia Carl Erik Olsen Søren Bak Birger Lindberg Møller 《Insect biochemistry and molecular biology》2013,43(11):1037-1044
Zygaena filipendulae accumulates the cyanogenic glucosides linamarin and lotaustralin by larval sequestration from the food plant or de novo biosynthesis. We have previously demonstrated that the Z. filipendulae male transfers linamarin and lotaustralin to the female in the course of mating. In this study we report the additional transfer of 5-hydroxytryptophan glucoside (5-(β-d-glucopyranosyloxy)-l-Tryptophan) from the Z. filipendulae male internal genitalia to the female spermatophore around 5 h into the mating process. 5-Hydroxytryptophan glucoside is present in the virgin male internal genitalia, and production continues during the early phase of mating. Following initiation of 5-hydroxytryptophan glucoside transfer to the female, the amount in male internal genitalia is drastically reduced until after mating where it is slowly replenished. For unambiguous structural identification, 5-hydroxytryptophan glucoside was chemically synthesized and used as an authentic standard. The biological function of 5-hydroxytryptophan glucoside remains to be established, although we have indications that it may be involved in inducing the female to stay in copula and delay egg-laying to prevent re-mating of the female. To our knowledge 5-hydroxytryptophan glucoside has not previously been reported present in animal tissues. 相似文献
125.
126.
Mehjabeen Hossain Dil Umme Salma Chowdhury Jacy Farhana Mohammed Touaha Akbar Ananya Chakraborty Shamima Islam Adnan Mannan 《Bioinformation》2013,9(4):187-192
Staphylococcus aureus is a gram positive bacterium, responsible for both community-acquired and hospital-acquired infection,
resulting in a mortality rate of 39%. 43.2% resistance to methicilin and emerging resistance to Fluroquinolone and Oxazolidinone,
have evoked the necessity of the establishment of alternative and effective therapeutic approach to treat this bacteria. In this
computational study, various database and online software are used to determine some specific targets of Staphylococcus aureus
N315 other than those used by Penicillin, Quinolone and Oxazolidinone. For this purpose, among 302 essential proteins, 101 nonhomologous
proteins were accrued and 64 proteins which are unique in several metabolic pathways of S. aureus were isolated by
using metabolic pathway analysis tools. Furthermore, 7 essentially unique enzymes involved in exclusive metabolic pathways were
revealed by this research, which can be potential drug target. Along with these important enzymes, 15 non-homologous proteins
located on membrane were identified, which can play a vital role as potential therapeutic targets for the future researchers. 相似文献
127.
Timothy C. Bray Nigel C. Bennett Osama B. Mohammed Abdulaziz N. Alagaili 《Zoology in the Middle East.》2013,59(4):283-288
Using non-destructive sampling we provide further genetic characterisations for spiny mice (Acomys dimidiatus/cahirinus) and gerbils (Gerbillus sp.) in three regions in Saudi Arabia. All individuals were sequenced for a fragment of the cytochrome b gene, and compared against available conspecifics and closely related taxa. We confirm the existence of a second Acomys dimidiatus/cahirinus lineage specific to the Arabian Peninsula as seen previously. The Arabian Gerbillus nanus is shown to group with Middle Eastern rather than African conspecifics. A second cryptic Gerbillus lineage was also sampled across multiple locations, which may be an uncharacterised G. dasyurus. 相似文献
128.
Hisham Mohammed Clive D’Santos Aurelien A. Serandour H. Raza Ali Gordon D. Brown Alan Atkins Oscar M. Rueda Kelly A. Holmes Vasiliki Theodorou Jessica L.L. Robinson Wilbert Zwart Amel Saadi Caryn S. Ross-Innes Suet-Feung Chin Suraj Menon John Stingl Carlo Palmieri Carlos Caldas Jason S. Carroll 《Cell reports》2013,3(2):342-349
Highlights? A proteomic method identifies protein-protein interaction in primary tumors ? GREB1 is the top estrogen-induced ER-interacting protein ? GREB1 is an essential ER cofactor recruited to chromatin ? GREB1 is an independent prognostic marker 相似文献
129.
Mohammed Sherif Debbie Waung Bihter Korbeci Valentina Mavisakalyan Robert Flick Greg Brown Mamdouh Abou‐Zaid Alexander F. Yakunin Emma R. Master 《Microbial biotechnology》2013,6(5):588-597
Multicopper oxidases can act on a broad spectrum of phenolic and non‐phenolic compounds. These enzymes include laccases, which are widely distributed in plants and fungi, and were more recently identified in bacteria. Here, we present the results of biochemical and mutational studies of small laccase (SLAC), a multicopper oxidase from Streptomyces coelicolor (SCO6712). In addition to typical laccase substrates, SLAC was tested using phenolic compounds that exhibit antioxidant activity. SLAC showed oxidase activity against 12 of 23 substrates tested, including caffeic acid, ferulic acid, resveratrol, quercetin, morin, kaempferol and myricetin. The kinetic parameters of SLAC were determined for 2,2′‐azino‐bis(3‐ethylbenzthiazoline‐6‐sulphonic acid), 2,6‐dimethoxyphenol, quercetin, morin and myricetin, and maximum reaction rates were observed with myricetin, where kcat and Km values at 60°C were 8.1 (± 0.8) s?1 and 0.9 (± 0.3) mM respectively. SLAC had a broad pH optimum for activity (between pH 4 and 8) and temperature optimum at 60–70°C. It demonstrated remarkable thermostability with a half‐life of over 10 h at 80°C and over 7 h at 90°C. Site‐directed mutagenesis revealed 17 amino acid residues important for SLAC activity including the 10 His residues involved in copper coordination. Most notably, the Y229A and Y230A mutant proteins showed over 10‐fold increase in activity compared with the wild‐type SLAC, which was correlated to higher copper incorporation, while kinetic analyses with S929A predicts localization of this residue near the meta‐position of aromatic substrates. 相似文献
130.
RG Maharaj C Alexander C H Bridglal A Edwards H Mohammed TA Rampaul S Sanchez GP Tanwing K Thomas 《Mental health in family medicine》2013,10(2):81-88
Objectives Somatoform disorders are common in international primary care settings, but have been little studied in the developing world. The objective of this study was to determine the prevalence of severe undifferentiated somatoform disorder, and its relationship to depression and anxiety, among patients attending walk-in clinics in Trinidad.Methods The study participants, who were all aged 18 years or older and attending walk-in clinics at 16 randomly selected health centres, were surveyed between May and August 2007 using the PRIME-MD questionnaire.Results There were 594 participants (the response rate was 92%), of whom 72.7% were female. Their ages ranged from 18 to 93 years, and 54.5% were over 50 years of age. In total, 37.2% were married and 25.9% were single. Indo-Trinidadians represented 43.1% and Afro-Trinidadians represented 36% of the study sample; 56.5% of the participants reported that their income was less than US$ 400 per month, and 65.7% were unemployed. At walk-in clinics in Trinidad, the estimated prevalence of severe undifferentiated somatoform disorder was 10.3% (95% CI: 7.86–12.74), that of hypochondriasis was 28.5% (95% CI: 24.9–32.1), and that of body dysmorphic disorder was 15.8% (95% CI: 11.9–18.7). Severe undifferentiated somatoform disorder was statistically significantly associated with gender and ethnicity but not with age, level of education, employment status or income. Chi-square testing found significant associations between the presence of severe undifferentiated somatoform disorder and both depression and anxiety (P < 0.05), between hypochondriasis and both anxiety and depression (P < 0.05), and between body dysmorphic disorder and depression (P < 0.05) but not anxiety. Regression analysis suggested that the demographic features that predicted severe undifferentiated somatoform disorder were being female or Indo-Trinidadian.Conclusions Walk-in clinics in Trinidad that serve older patients on a lower income have a high proportion of patients with somatoform disorders as measured by the PRIME-MD scale. These patients exhibit many features of anxiety and depression. These findings have implications for medical training and service delivery. 相似文献