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71.
Olivier Escaffre Cyril Le Nou?n Michel Amelot Xavier Ambroggio Kristen M. Ogden Olivier Guionie Didier Toquin Hermann Müller Mohammed R. Islam Nicolas Eterradossi 《Journal of virology》2013,87(5):2767-2780
Infectious bursal disease virus (IBDV) causes an economically significant disease of chickens worldwide. Very virulent IBDV (vvIBDV) strains have emerged and induce as much as 60% mortality. The molecular basis for vvIBDV pathogenicity is not understood, and the relative contributions of the two genome segments, A and B, to this phenomenon are not known. Isolate 94432 has been shown previously to be genetically related to vvIBDVs but exhibits atypical antigenicity and does not cause mortality. Here the full-length genome of 94432 was determined, and a reverse genetics system was established. The molecular clone was rescued and exhibited the same antigenicity and reduced pathogenicity as isolate 94432. Genetically modified viruses derived from 94432, whose vvIBDV consensus nucleotide sequence was restored in segment A and/or B, were produced, and their pathogenicity was assessed in specific-pathogen-free chickens. We found that a valine (position 321) that modifies the most exposed part of the capsid protein VP2 critically modified the antigenicity and partially reduced the pathogenicity of 94432. However, a threonine (position 276) located in the finger domain of the virus polymerase (VP1) contributed even more significantly to attenuation. This threonine is partially exposed in a hydrophobic groove on the VP1 surface, suggesting possible interactions between VP1 and another, as yet unidentified molecule at this amino acid position. The restored vvIBDV-like pathogenicity was associated with increased replication and lesions in the thymus and spleen. These results demonstrate that both genome segments influence vvIBDV pathogenicity and may provide new targets for the attenuation of vvIBDVs. 相似文献
72.
Md. Ejaz Ahmed Mohd. Moshahid Khan Hayate Javed Kumar Vaibhav Andleeb Khan Rizwana Tabassum Mohammad Ashafaq Farah Islam Mohammed M. Safhi Fakhrul Islam 《Neurochemistry international》2013
Alzheimer’s disease (AD) is a progressive neurodegenerative disorder resulting in cognitive decline and enhancement of oxidative loads in the brain. Flavonoids have been considered to exert human health benefits by anti-oxidant and anti-inflammatory properties. The present study is aimed to elucidate the neuroprotective effect of catechin hydrate (CH), a natural flavanoid with potential antioxidant and anti-inflammatory properties, on intracerebroventricular streptozotocin (ICV-STZ) induced neuronal loss and memory impairment. To test this hypothesis, male Wistar rats were pretreated with CH (10 and 20 mg/kg bwt) orally once daily for 21 days and then bilaterally injected with ICV-STZ (3 mg/kg bwt), while sham group rats receive the same volume of vehicle. After 2 weeks of ICV-STZ infusion, rats were tested for cognitive performance using Morris water maze (MWM) test and then sacrifice for biochemical and histopathological assays. CH was found to be successful in upregulating the antioxidant status and prevented the memory loss. The expression of choline acetyl transferase (ChAT) was decreased in ICV-STZ group and CH pretreatment increases the expression of ChAT. Moreover, inflammatory mediators like TNF-α, IL-1β levels and expression of iNOS were significantly attenuated by CH pretreatment. The study suggests that CH is effective in preventing memory loss, ameliorating the oxidative stress and might be beneficial for the treatment of sporadic dementia of Alzheimer’s type (SDAT). 相似文献
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74.
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
75.
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
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77.
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
78.
Sabry M. Attia Sheikh F. Ahmad Mushtaq A. Ansaria Ahmed Nadeem Othman A. Al-Shabanah Mohammed M. Al-Harbi Saleh A. Bakheet 《PloS one》2016,11(9)
Dexrazoxane has been approved to treat anthracycline-induced cardiomyopathy and extravasation. However, the effect of dexrazoxane on epirubicin-induced genetic alterations in germ cells has not yet been reported. Thus, the aim of this study was to determine whether dexrazoxane modulates epirubicin-induced genetic damage in the germ cells of male mice. Our results show that dexrazoxane was not genotoxic at the tested doses. Furthermore, it protected mouse germ cells against epirubicin-induced genetic alterations as detected by the reduction in disomic and diploid sperm, spermatogonial chromosomal aberrations, and abnormal sperm heads. The attenuating effect of dexrazoxane was greater at higher dose, indicating a dose-dependent effect. Moreover, sperm motility and count were ameliorated by dexrazoxane pretreatment. Epirubicin induced marked biochemical changes characteristic of oxidative DNA damage including elevated 8-hydroxy-2ʹ-deoxyguanosine levels and reduction in reduced glutathione. Pretreatment of mice with dexrazoxane before epirubicin challenge restored these altered endpoints. We conclude that dexrazoxane may efficiently mitigate the epirubicin insult in male germ cells, and prevent the enhanced risk of abnormal reproductive outcomes and associated health risks. Thus, pretreating patients with dexrazoxane prior to epirubicin may efficiently preserve not only sperm quality but also prevent the transmission of genetic damage to future generations. 相似文献
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