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81.
Kumar Alok Singh Pradyumn Pandey Anshuman Gosipatala Sunil Babu 《Molecular biology reports》2020,47(9):6919-6927
Molecular Biology Reports - Promoter methylation mediated silencing of tumor suppressor genes plays an important role in the tumorigenesis of colorectal carcinoma (CRC). Tumor suppressor gene,... 相似文献
82.
Use of chemical activator for the management of root-knot disease in medicinal and aromatic plants can become an attractive alternative to traditionally used nematicides. Large numbers of chemical molecules are present in the plants and are involved in the induction of different types of proteins. The purpose of our research study is to explore the possibilities of resistance factors that are inherent in the plant by treating them with few chemical activators to activate against root-knot nematode infection. Efforts were made to achieve a satisfactory suppression of root-knot nematode, Meloidogyne incognita, a serious menace to successful cultivation of chamomile, Matricaria recutita L. Rauch (syn. Matricaria chamomilla L. Fain. Asteraceae) causing root-knot disease through use of different chemical activators. Here we examined selected groups of resistance activator viz. Isonicotinamide, 2-chloronicotinic acid, 5-nitrosalicylic acid, 4-chlorosalicylic acid, DL-2 aminobutyric acid, 2-aminobutyric acid, O-acetylsalicylic acid, 4-amino salicylic acid, salicylic acid and these were used as soil drench using 3 week old seedlings transplanted to root-knot nematode infested pots. Maximum reduction in root-knot severity and nematode population occurred with 4-chlorosalicylic acid, O-acetyl salicylic acid, 2-chloronicotinic acid and gave significant flower yield advantages. Present experiment suggests a strong possibility of these activators in integrated management for protection against plant parasitic nematodes. 相似文献
83.
Ajay Kumar D.M. Pandey Thomson Abraham Jacob Mathew Padma Ramachandran 《Archives Of Phytopathology And Plant Protection》2013,46(6):710-720
Tapping panel dryness (TPD) syndrome affecting rubber tree (Hevea brasiliensis) is known to reduce natural latex production. Its aetiology remains ambiguous despite long years of research. A low molecular weight RNA similar to viroid RNA was isolated from TPD-affected samples of rubber trees. In the present study, a modified return-polyacrylamide gel electrophoresis procedure was standardised. The viroid-like low molecular weight (LMW) RNA was found associated with leaf, bark and root tissues and rubber seedlings. The technique was employed to detect LMW RNA in different clones of rubber planted in different locations and in bud-grafted plants. The LMW RNA isolated from TPD-affected trees was found infectious on seedlings of tomato cv Pusa Ruby. The LMW RNA was reisolated from symptomatic tomato leaves but not from control plants. This is for the first time that a biotic agent, a viroid RNA, is found consistently associated with the syndrome. The technology developed can be useful to demonstrate the onset of TPD in untapped trees in the absence of other methods such as nucleic acid hybridisation. 相似文献
84.
Surya Prakash Bhatt Priyanka Nigam Anoop Misra Randeep Guleria Kalpana Luthra Ravindra Mohan Pandey M.A. Qadar Pasha 《Gene》2013
Background
Genetics of non-alcoholic fatty liver (NAFLD) in Asian Indians has been inadequately studied. We investigated the association of polymorphisms C161T and Pro12Ala of peroxisome proliferator-activated receptor gamma (PPARγ) with clinical and biochemical parameters in Asian Indians with NAFLD.Methods
In this case–control study, 162 NAFLD cases and 173 controls were recruited. Abdominal ultrasound, clinical and biochemical profiles, fasting insulin levels and value of homeostasis model assessment of insulin resistance were determined. Polymerase chain reaction–restriction fragment length polymorphisms of two polymorphisms were performed. The association of these polymorphisms with clinical and biochemical parameters was analysed.Results
Higher frequency of Ala and T alleles of PPARγ was obtained in cases. Ala/Ala genotype of PPARγ (Pro12Ala) was associated with significantly higher serum triglycerides (TG), alkaline phosphatase (ALK) and waist–hip ratio in cases as compared to controls. In C161T polymorphism, TT genotype was significantly increased TG (p = 0.04), total cholesterol (p = 0.01), ALK (p = 0.04) and gamma-glutamyl transpeptidase (p = 0.007) in cases. The linkage disequilibrium for these two single-nucleotide polymorphisms of PPARγ was differed in cases (D1 = 0.1; p = 0.006) and controls (D1 = 0.07; p = 0.1). Using a multivariate analysis after adjusting for age, sex and body mass index, the presence of NAFLD was linked to these two polymorphisms (odds ratio 1.64 (95% CI: 1.09–2.45, p = 0.05)].Conclusion
Asian Indians in north India carrying the alleles Ala and T of PPARγ (Pro12Ala and C161T) polymorphisms are predisposed to develop NAFLD. 相似文献85.
86.
Sameeksha Tiwari Manika Awasthi Swati Singh Veda P. Pandey 《Journal of biomolecular structure & dynamics》2013,31(13):3376-3387
Protein–protein interactions (PPI) are a new emerging class of novel therapeutic targets. In order to probe these interactions, computational tools provide a convenient and quick method towards the development of therapeutics. Keeping this in view the present study was initiated to analyse interaction of tumour suppressor protein p53 (TP53) and breast cancer associated protein (BRCA1) as promising target against breast cancer. Using computational approaches such as protein–protein docking, hot spot analyses, molecular docking and molecular dynamics simulation (MDS), stepwise analyses of the interactions of the wild type and mutant TP53 with that of wild type BRCA1 and their modulation by alkaloids were done. Protein–protein docking method was used to generate both wild type and mutant complexes of TP53-BRCA1. Subsequently, the complexes were docked using sixteen different alkaloids, fulfilling ADMET and Lipinski’s rule of five criteria, and were compared with that of a well-known inhibitor of PPI, namely nutlin. The alkaloid dicentrine was found to be the best docked alkaloid among all the docked alklaloids as well as that of nutlin. Furthermore, MDS analyses of both wild type and mutant complexes with the best docked alkaloid i.e. dicentrine, revealed higher stability of mutant complex than that of the wild one, in terms of average RMSD, RMSF and binding free energy, corroborating the results of docking. Results suggested more pronounced interaction of BRCA1 with mutant TP53 leading to increased expression of mutated TP53 thus showing a dominant negative gain of function and hampering wild type TP53 function leading to tumour progression. 相似文献
87.
88.
Nitin Kumar Pandey Sudeshna Ghosh Nóra Veronika Nagy 《Journal of biomolecular structure & dynamics》2013,31(9):1366-1378
Protein aggregation is related to a series of pathological disorders the main cause of which are the fibrillar species generated during the process. Human serum albumin (HSA) undergoes rapid fibrillation in the presence of Cu(II) at pH 7.4 in 60% ethanol after 6-h incubation (~65?°C) followed by room temperature incubation. Here, we have investigated the effect of a stoichiometric variation of Cu(II) on the self-assembly of HSA using Congo red and thioflavin T dye-binding studies, circular dichroism spectroscopy, Fourier transform infrared spectroscopy, electron paramagnetic resonance spectroscopy, fluorescence microscopy and transmission electron microscopy. The simulation of EPR spectra suggests that with the increment in Cu(II) ion concentration, there is a change in ligand field coordination. Kinetic parameters indicate reduced cooperativity that may be related to the nonspecific coordination on increment of Cu(II) concentration. Cu(II) is also able to direct the accumulation of a large number of fibers along with a formation of dense fibrillar network which is evident from microscopic images. 相似文献
89.
Rajan Kumar Pandey Drista Sharma Tarun Kumar Bhatt Shyam Sundar 《Journal of biomolecular structure & dynamics》2013,31(12):2541-2553
Visceral leishmaniasis (VL) affects Indian subcontinent, African and South American continent, and it covers 70 countries worldwide. Visceral form of leishmaniasis is caused by Leishmania donovani in Indian subcontinent which is lethal if left untreated. Extensive resistance to antileishmanial drugs such as sodium stibogluconate, pentamidine and miltefosine and their decreased efficacy has been reported in the endemic region. Amphotericin B drug has shown good antileishmanial activity with significant toxicity, but its cost of treatment has limited the outreach of this treatment to affected people living in endemic zone. So, there is an urgent need to identify new antileishmanial drugs with excellent activity and minimal toxicity issues. Trypanothione reductase, a component of antioxidant system, is necessary for parasite growth and survival to raise infection. To develop potential inhibitor, we docked nine hundred and eighty-four 5-nitroimidazole analogues along with clomipramine which is a well-known inhibitor for TR. Total one hundred and forty-seven 5-nitroimidazole analogues with better docking score than clomipramine were chosen for ADMET and QikProp studies. Among these imidazole analogues, total twenty-four imidazole analogues and clomipramine were chosen on the basis of their ADMET, QikProp, and prime MM-GBSA study. Later on, two analogues with best MM-GBSA dG bind were undergone molecular dynamic simulation to ensure protein–ligand interactions. Using above approach, we confirm that ethyl 2-acetyl-5-[4-butyl-2-(3-hydroxypentyl)-5-nitro-1H-imidazol-1-yl]pent-2-enoate can be a drug candidate against L. donovani for the treatment of VL in the Indian subcontinent. 相似文献
90.
Epigenetic mechanisms of plant stress responses and adaptation 总被引:3,自引:0,他引:3
Pranav Pankaj Sahu Garima Pandey Namisha Sharma Swati Puranik Mehanathan Muthamilarasan Manoj Prasad 《Plant cell reports》2013,32(8):1151-1159
Epigenetics has become one of the hottest topics of research in plant functional genomics since it appears promising in deciphering and imparting stress-adaptive potential in crops and other plant species. Recently, numerous studies have provided new insights into the epigenetic control of stress adaptation. Epigenetic control of stress-induced phenotypic response of plants involves gene regulation. Growing evidence suggest that methylation of DNA in response to stress leads to the variation in phenotype. Transposon mobility, siRNA-mediated methylation and host methyltransferase activation have been implicated in this process. This review presents the current status of epigenetics of plant stress responses with a view to use this knowledge towards engineering plants for stress tolerance. 相似文献