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131.
Muhammad A Anis I Ali Z Awadelkarim S Khan A Khalid A Shah MR Galal M Khan IA Iqbal Choudhary M 《Bioorganic & medicinal chemistry letters》2012,22(1):610-612
A new methylene-bridged bisflavonoid, methylenebissantin (1), and nine known compounds, including flavonoids (2-5), diterpenoids (6 and 7), and phenol derivatives (8-10) were isolated from the aerial parts of Dodonaea viscosa Jacq. The structure elucidation was based on spectroscopic data analyses. The isolated compounds were evaluated for the inhibition of Plasmodium falciparum enoyl-ACP reductase (PfENR). Methylenebissantin (1) exhibited a moderate inhibition (IC(50) 91.13 μM) against PfENR. 相似文献
132.
Saqib H. Ansari Tahir S. Shamsi Mushtaq Ashraf Tasneem Farzana Muneera Bohray Kousar Perveen Sajida Erum Iqra Ansari Muhammad Nadeem Ahmed Masood Ahmed Faizan Raza 《Indian journal of human genetics》2012,18(2):193-197
BACKGROUND:
β -Thalassaemia, an autosomal recessive hemoglobinopathy, is one of the commonest genetically transmitted disorders throughout the world. Collective measures including carrier identification, genetic counseling and prenatal diagnosis are required for preventing β-thalassemia.Aim:
To achieve this objective, Identification of the spectrum of genetic mutations, especially for various ethnic backgrounds in Pakistan. Therefore, we designed a cross sectional prospective study to identify the frequency of various gene mutations in different ethnic groups of Pakistan.MATERIALS AND METHODS:
Over a 5-year period, DNA from 648 blood samples {including specimens of chorionic villus sampling (CVS)} were analyzed for the twelve most common β-thalassemia mutations found in the Pakistani population by a Multiplex amplification refractory mutation system (ARMS). Each sample was analyzed for the mutation as well as the normal gene, appropriate with negative and positive controls, and reagent blanks.RESULTS:
Out of 648 samples mutations were identified in 640 (98.75%) samples by multiplex ARMS. 8 common β-thalassemia mutations were identified in 8 different ethnic groups accounting for 93.9% of the β-thalasemia alleles.CONCLUSIONS:
Based on the outcome of this study a cost effective proposal is formulated for detection of β-thalassemia mutations. 相似文献133.
Prabu SK Anandatheerthavarada HK Raza H Srinivasan S Spear JF Avadhani NG 《The Journal of biological chemistry》2006,281(4):2061-2070
We have investigated the effects of hypoxia and myocardial ischemia/reperfusion on the structure and function of cytochrome c oxidase (CcO). Hypoxia (0.1% O(2) for 10 h) and cAMP-mediated inhibition of CcO activity were accompanied by hyperphosphorylation of subunits I, IVi1, and Vb and markedly increased reactive O(2) species production by the enzyme complex in an in vitro system that uses reduced cytochrome c as an electron donor. Both subunit phosphorylation and enzyme activity were effectively reversed by 50 nm H89 or 50 nm myristoylated peptide inhibitor (MPI), specific inhibitors of protein kinase A, but not by inhibitors of protein kinase C. In rabbit hearts subjected to global and focal ischemia, CcO activity was inhibited in a time-dependent manner and was accompanied by hyperphosphorylation as in hypoxia. Additionally, CcO activity and subunit phosphorylation in the ischemic heart were nearly completely reversed by H89 or MPI added to the perfusion medium. Hyperphosphorylation of subunits I, IVi1, and Vb was accompanied by reduced subunit contents of the immunoprecipitated CcO complex. Most interestingly, both H89 and MPI added to the perfusion medium dramatically reduced the ischemia/reperfusion injury to the myocardial tissue. Our results pointed to an exciting possibility of using CcO activity modulators for controlling myocardial injury associated with ischemia and oxidative stress conditions. 相似文献
134.
Membranes are not just rafts 总被引:1,自引:0,他引:1
A new definition for lipid rafts was coined at the Keystone Symposium of Lipid Rafts and Cell Function based on recent advances in the field. The revised definition lumps all membrane heterogeneities that are not rafts into a single class of "non-raft". In this commentary, we suggest that "non-raft" domains encompass a variety of membrane heterogeneities and are quite diverse in composition and origin. A good starting point for the study of this diversity would be phospholipids with unsaturated acyl chains, which display little affinity for cholesterol; these lipids are abundant in membranes such as the endoplasmic reticulum and that may form their own macro- or microdomains. 相似文献
135.
OBJECTIVE: To evaluate the utility of rapid intraoperative crush smear cytologic diagnosis of central and peripheral nervous system lesions and to determine the accuracy and relevance of the accuracy of the intraoperative cytologic diagnosis when compared to the final paraffin section diagnosis. STUDY DESIGN: The crush (squash) smear technique was introduced at Sher-i-Kashmir Institute of Medical Sciences in May 2003. The 8 months of 2003 were used for standardization of the procedure. In 2004, 151 patients with open neurosurgical specimens or stereotactic biopsies were diagnosed intraoperatively by crush smears, and the diagnosis was compared with final diagnosis on paraffin sections of the same tissue samples. No supplementation of frozen sections was used. RESULTS: Of 151 cases, 144 were diagnosed accurately intraoperatively by crush smear cytology when compared with the respective paraffin section diagnoses. The diagnostic accuracy attained was 95.36%. Each case was diagnosed within 10 minutes after receipt of sample. Neurosurgical procedure (open or stereotaxy) did not affect diagnostic accuracy. CONCLUSION: In the expert hands of a pathologist with good exposure neurosurgical specimens, crush smear cytology is an accura and reliable procedure for the intraoperative diagnosis central nervous system tumors. 相似文献
136.
137.
Diazotrophic endophytes of native black cottonwood and willow 总被引:1,自引:0,他引:1
Sharon L. Doty Brian Oakley Gang Xin Jun Won Kang Glenda Singleton Zareen Khan Azra Vajzovic James T. Staley 《Symbiosis (Philadelphia, Pa.)》2009,47(1):23-33
Poplar and willow are economically-important, fast-growing tree species with the ability to colonize nutrient-poor environments.
To initiate a study on the possible contribution of endophytes to this ability, we isolated bacteria from within surface-sterilized
stems of native poplar (Populus trichocarpa) and willow (Salix sitchensis) in a riparian system in western Washington state. Several of the isolates grew well in nitrogen-limited medium. The presence
ofnifH, a gene encoding one of the subunits of nitrogenase, was confirmed in several of the isolates including species ofBurkholderia, Rahnella, Sphingomonas, andAcinetobacter. Nitrogenase activity (as measured by the acetylene reduction assay) was also confirmed in some of the isolates. The presence
of these diazotrophic microorganisms may help explain the ability of these pioneering tree species to grow under nitrogen
limitation. 相似文献
138.
Nilantha Sirisoma Azra Pervin Bao Nguyen Candace Crogan-Grundy Shailaja Kasibhatla Ben Tseng John Drewe Sui Xiong Cai 《Bioorganic & medicinal chemistry letters》2009,19(8):2305-2309
As a continuation of our efforts to discover and develop the apoptosis inducing 4-anilino-2-(2-pyridyl)pyrimidines as potential anticancer agents, we explored replacing the 2-pyridyl group by other aryl groups. SAR studies showed that the 2-pyridyl group can be replaced by a 3-pyridyl, 4-pyridyl and 2-pyrazinyl group, and that the SAR for the anilino group was similar to that of the 2-pyridyl series. However, replacement of the 2-pyridyl group by a phenyl group, a 3,5-dichloro-4-pyridyl group, or a saturated ring led to inactive compounds. Several potent compounds, including 2f, 3d, 3j and 4a, with EC50 values of 0.048–0.024 μM in the apoptosis induction assay against T47D cells, were identified through the SAR studies. In a tubulin polymerization assay, compound 2f, which was active against all the three cell lines tested (T47D, HTC116 and SNU398), inhibited tubulin polymerization with an IC50 value of 0.5 μM, while compound 2a, which was active against T47D cells but not active against HTC116 and SNU398 cells, was not active in the tubulin assay at up to 50 μM. 相似文献
139.
Maria D. Van Kerkhove Sowath Ly Javier Guitian Davun Holl Sorn San Punam Mangtani Azra Ghani Sirenda Vong 《PloS one》2009,4(7)
Background
Since 2004, 21 highly pathogenic avian influenza H5N1 outbreaks in domestic poultry and eight human cases have been confirmed in Cambodia. As a result, a large number of avian influenza education campaigns have been ongoing in provinces in which H5N1outbreaks have occurred in humans and/or domestic poultry.Methodology/Principal Findings
Data were collected from 1,252 adults >15 years old living in two southern provinces in Cambodia where H5N1 has been confirmed in domestic poultry and human populations using two cross-sectional surveys conducted in January 2006 and in November/December 2007. Poultry handling behaviors, poultry mortality occurrence and self-reported notification of suspect H5N1 poultry cases to animal health officials in these two surveys were evaluated. Our results demonstrate that although some at risk practices have declined since the first study, risky contact with poultry is still frequent. Improved rates of reporting poultry mortality were observed overall, but reporting to trained village animal health workers decreased by approximately 50%.Conclusions/Significance
Although some improvements in human behavior have occurred, there are still areas—particularly with respect to the handling of poultry among children and the proper treatment of poultry and the surrounding household environment—that need to be addressed in public health campaigns. Though there were some differences in the sampling methods of the 2006 and 2007 surveys, our results illustrate the potential to induce considerable, potentially very relevant, behavioral changes over a short period of time. 相似文献140.
Azra C. Ghani Colin J. Sutherland Eleanor M. Riley Chris J. Drakeley Jamie T. Griffin Roly D. Gosling Joao A. N. Filipe 《PloS one》2009,4(2)