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71.
Picrorhiza kurrooa L., a high altitude medicinal plant, is known for its drug content called Kutkin. In the present study, DNA-based molecular marker techniques, viz. simple sequence repeats (SSR) and cytochrome P-450 markers were used to estimate genetic diversity in Picrorhiza kurrooa. Twenty five accessions of Picrorhiza kurrooa, collected from ten different eco-geographical locations were subjected to 22 SSR and eight cytochrome P-450 primer pairs, out of which 13 SSR markers detected mean 5.037 alleles with a mean polymorphic information content (PIC) of 0.7718, whereas eight cytochrome P-450 markers detected mean 5.0 alleles with a mean PIC of 0.7596. Genetic relationship among the accessions was estimated by constructing the dendrograms using SSR and cytochrome P-450 data. There was a clear consistency between SSR and cytochrome P-450 trees in terms of positioning of most Picrorhiza accessions. SSR markers could cluster various Picrorhiza kurrooa accessions based on their geographical locations whereas cytochrome P-450 markers could cluster few accessions as per their geographical locations. The Mantel test between SSR and cytochrome P-450 markers revealed a good fit correlation (r = 0.6405). The dendrogram constructed using the combined data of SSR and cytochrome P-450s depicted two clusters of accessions based on its eco-geographical locations whereas two clusters contained the accessions from mixed eco-geographical locations. Overall, the results of the present study point towards quiet high degree of genetic variation among the accessions of each eco-geographic region. 相似文献
72.
73.
Richard K. Amewu James Chadwick Afthab Hussain Somnath Panda Rinki Rinki Omar Janneh Stephen A. Ward Candel Miguel Hollie Burrell-Saward Livia Vivas Paul M. O’Neill 《Bioorganic & medicinal chemistry》2013,21(23):7392-7397
The synthesis of a range of mono spiro and dispiro 1,2,4,5-tetraoxane dimers is described. Selected molecules were examined in in vitro assays to determine their antimalarial and anticancer potential. Our studies reveal that several molecules possess potent nanomolar antimalarial and single digit micromolar antiproliferative IC50s versus colon (HT29-AK and leukemia (HL60) cell lines. 相似文献
74.
Anna Marchiani Stefano Mammi Giuliano Siligardi Rohanah Hussain Isabella Tessari Luigi Bubacco Giovanna Delogu Davide Fabbri Maria A. Dettori Daniele Sanna Sonia Dedola Pier A. Serra Paolo Ruzza 《Amino acids》2013,45(2):327-338
Curcumin, a dietary polyphenol, has shown a potential to act on the symptoms of neurodegenerative disorders, including Alzheimer’s and Parkinson’s diseases, as a consequence of its antioxidant, anti-inflammatory and anti-protein aggregation properties. Unfortunately, curcumin undergoes rapid degradation at physiological pH into ferulic acid, vanillin and dehydrozingerone, making it an unlikely drug candidate. Here, we evaluated the ability of some curcumin by-products: dehydrozingerone (1), its O-methyl derivative (2), zingerone (3), and their biphenyl analogues (4–6) to interact with α-synuclein (AS), using CD and fluorescence spectroscopy. In addition, the antioxidant properties and the cytoprotective effects in rat pheochromocytoma (PC12) cells prior to intoxication with H2O2, MPP+ and MnCl2 were examined while the Congo red assay was used to evaluate the ability of these compounds to prevent aggregation of AS. We found that the biphenyl zingerone analogue (6) interacts with high affinity with AS and also displays the best antioxidant properties while the biphenyl analogues of dehydrozingerone (4) and of O-methyl-dehydrozingerone (5) are able to partially inhibit the aggregation process of AS, suggesting the potential role of a hydroxylated biphenyl scaffold in the design of AS aggregation inhibitors. 相似文献
75.
Mahmud Hussain Dustin Lockney Ruqi Wang Nimish Gera Balaji M. Rao 《Biotechnology progress》2013,29(1):237-246
Immunoaffinity separation of large multivalent species such as viruses is limited by the stringent elution conditions necessary to overcome their strong and highly avid interaction with immobilized affinity ligands on the capture surface. Here we present an alternate strategy that harnesses the avidity effect to overcome this limitation. Red clover necrotic mosaic virus (RCNMV), a plant virus relevant to drug delivery applications, was chosen as a model target for this study. An RCNMV binding protein (RBP) with modest binding affinity (KD ~100 nM) was generated through mutagenesis of the Sso7d protein from Sulfolobus solfataricus and used as the affinity ligand. In our separation scheme, RCNMV is captured by a highly avid interaction with RBP immobilized on a nickel surface through a hexahistidine (6xHis) tag. Subsequently, disruption of the multivalent interaction and release of RCNMV is achieved by elution of RBP from the nickel surface. Finally, RCNMV is separated from RBP by exploiting the large difference in their molecular weights (~8 MDa vs. ~10 kDa). Our strategy not only eliminates the need for harsh elution conditions, but also bypasses chemical conjugation of the affinity ligand to the capture surface. Stable non‐antibody affinity ligands to a wide spectrum of targets can be generated through mutagenesis of Sso7d and other hyperthermophilic proteins. Therefore, our approach may be broadly relevant to cases where capture of large multivalent species from complex mixtures and subsequent release without the use of harsh elution conditions is necessary. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2013 相似文献
76.
Atika?MansoorEmail author Lubna?Ali Noor-ul?Sabah Asraf?Hussain?Hashmi Mohammad?Haroon?Khan Syed?Ali?Raza?Kazmi Nafees?Ahmad Saima?Siddiqi Khalid?Mehmood?Khan 《Virology journal》2013,10(1):352
Background
Hepatitis C virus (HCV) is a major cause of liver cirrhosis and hepatocellular carcinoma and infects about 3% world population. Response to interferon therapy depends upon the genotype of the virus and factors associated with the host. Despite a good response to interferon therapy, a considerable number of genotype 3a infected patients remains unalleviated.Results
In total forty-nine patients including twenty-five non-responders (non-SVR) and twenty-four responders (SVR) were recruited. Patients were tested for viral status at different intervals and the isolated RNA was sequenced for the NS5A region in both groups. The comparison of PKRBD of HCV between the SVR and non-SVR patients did not confirm any significant difference in the number of mutations. However, when the sequence downstream to the PKRBD of NS5A was compared, two important statistically significant mutations were observed; at positions 2309 (Ala to Ser) and 2326 (Gly to Ala). These mutations were then analysed for tertiary protein structure and important structural changes were observed. Statistically significant difference was also observed when age groups of patients were compared; younger patients showed better response than the older ones.Conclusions
The region between PKRBD and IRRDR may be important for prediction of response to IFN therapy for genotype 3a. ISDR and PKRBD have not shown any involvement in treatment response. Further functional analyses of these findings can help in understanding the involvement of the NS5A region in interferon treatment of HCV-3a infected patients.77.
78.
Sanghamitra Pati Mohammad Akhtar Hussain Abhimanyu Singh Chauhan Diptimayee Mallick Sukdev Nayak 《Cancer epidemiology》2013,37(6):973-978
Cancer is a leading cause of mortality worldwide. Early diagnosis and treatment of cancer may curb the growing burden of the disease. Understanding cancer patients’ navigation pathways for seeking treatment is important in order to facilitate early diagnosis and treatment. With this background we conducted a hospital-based cross-sectional study comprising 68 randomly selected cancer inpatients in a tertiary cancer specialty hospital in Odisha, India, to explore the treatment-seeking pathways of the cancer patients and the barriers and enablers in seeking treatment. Financial constraint is one of the major reasons for the delay in accessing treatment, even when patients are suspected of or diagnosed with cancer. Low awareness of the presenting signs and symptoms of cancer and limited knowledge of the availability of cancer diagnosis and treatment facilities are major factors contributing to delay. Family and friends’ support is found to be the major enabling factor toward seeking treatment. Generation of awareness of cancer among the general population and primary-care practitioners – including those in alternative systems of medicine – is important. Information on diagnostic and treatment services appears to be a felt need. 相似文献
79.
Yongqiang Liu Fuqian Yang Hongtie Pu Junping Su Zongjiang Liu Khalid Hussain Dhiloo Zhongyue Wang 《PloS one》2016,11(11)
Grape phylloxera, Daktulosphaira vitifoliae (Fitch) (Hemiptera, Phylloxeridae), is a very destructive insect pest of grapevines. Intercropping of Achyranthes bidentata Blume (f. Amaranthaceae) and Vitis spp. grapevines can be useful to control this pest. In the present study, the toxicity of 22 compounds, known to be present in A. bidentata, to grape phylloxera was evaluated. All treatments were toxic towards grape phylloxera but the degree of toxicity differed between treatments. Among the 22 tested compounds, several of which proved toxic towards grape phylloxera. However β-ecdysterone had higher toxic effects against grape phylloxera, with LC50 values of 175.73 mg a.i. liter-1. In addition, we assessed the sublethal effects of LC10, LC20 and LC40 of β-ecdysterone on grape phylloxera. The fourth instar and adult developmental periods and total life span were significantly prolonged by LC40 of β-ecdysterone. Fecundity decreased when grape phylloxera were exposed to LC20 and LC40 of β-ecdysterone. In addition, LC40 of β-ecdysterone decreased the intrinsic rate of increase (rm) and the finite rate of increase (λ) and prolonged the population doubling time (DT). The net reproductive rate (R0) was significantly reduced by both the LC20 and LC40 β-ecdysterone treatments. Our results demonstrated that β-ecdysterone had higher toxic effects and significant sublethal effects on grape phylloxera, and showed potential control of grape phylloxera. 相似文献
80.
Ahtesham Hussain Mukesh Kumar Yadav Shambhunath Bose Jing-Hua Wang Dongwoo Lim Yun-Kyung Song Seong-Gyu Ko Hojun Kim 《PloS one》2016,11(11)
BackgroundObesity has become a major global health challenge due to its increasing prevalence, and the associated health risk. It is the main cause of various metabolic diseases including diabetes, hypertension, cardiovascular disease, stroke and certain forms of cancer.