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91.
Vijay C. Verma Surendra K. Gond Anuj Kumar Ravindra N. Kharwar Lori-Ann Boulanger Gary A. Strobel 《Indian journal of microbiology》2011,51(4):469-476
Azadirachta indica A. Juss. (neem), native to India, is well known worldwide for its insecticidal and ethanopharmacological properties. Although
endophytic microbes are known from this plant as only leaves and stems were the subjects of past reports. Now, a variety of
procedures and a number of different media were used to isolate the maximum number of endophytic fungi from unripe fruits
and roots. A total of 272 isolates of 29 filamentous fungal taxa were isolated at rate of 68.0% from 400 samples of three
different individual trees (at locations-Az1, Az2, Az3). Mycological agar (MCA) medium yielded the highest number of isolates
(95, with a 14.50% isolation rate) with the greatest species richness. Mycelia Sterilia (1, 2, 3) accounted for 11.06%, Coelomycetes
7.25%, while Hyphomycetes showed the maximum number of representative isolates (81.69%). Mycelia-Sterilia (1, 2, 3), based
on their 5.8S ITS 1, ITS2 and partial 18S and 28S rDNA sequences were identified as Fusarium solani (99%), Chaetomium globosum (93%) and Chaetomium globosum (93%) respectively. Humicola, Drechslera, Colletotrichum, and Scytalidium sp. were some of the peculiar fungal endophytes recovered from this plant. 相似文献
92.
Saborni Maiti Utkarsh Ravindra Moon Paramita Bera Tanmoy Samanta Adinpunya Mitra 《Acta Physiologiae Plantarum》2014,36(10):2597-2605
This study was designed to examine the chemical compositions of scent volatiles and antioxidant activities of Polianthes tuberosa L. flower extract in six different solvents. The main constituents of the volatile components were benzyl benzoate, methyl 2-amino benzoate, methyl isoeugenol, isoeugenol, benzyl salicylate, methyl salicylate, geraniol and 1,8-cineole. Total phenolic content of floral extracts in water, methanol, ethanol, ethyl acetate, hexane and dichloromethane were found to be 0.094, 0.18, 0.14, 0.007, 0.004 and 0.110 mg gallic acid equivalent/mg fresh weight, respectively. The methanol soluble fraction showed highest values of antioxidant activity through DPPH and ABTS assays. Methanol extract effectively inhibits the non site-specific DNA strand breakage caused by Fenton’s reagents. Dichloromethane and aqueous fractions also exhibited high antioxidant capacities. Aqueous extract showed highest value in FRAP assay. 相似文献
93.
94.
Vineeta Gupta Ravindra Kumar Garg Kamlesh Kumar Pant Sanjay Khattri 《Bioinformation》2014,10(6):342-346
Parkinson׳s disease is the second most common neurodegenerative disorder. The exact cause of selective dopaminergic
neurodegeneration is unknown, but it is supposed that etiology of Parkinson׳s disease is multifactorial and consists of an
interaction between environmental factors and genetic predisposition. To find out the association between environmental factors
and risk of Parkinson׳s disease, a case control study was designed including 97 Parkinson׳s disease patients and 97 controls.
Logistic regression analysis was used to determine the risk factors for Parkinson׳s disease. Results from the present study showed
that gender, religion, education, place of living, occupation, dietary habits, tobacco chewing, smoking, alcohol intake, and head
injury had no association with PD. However, chemical exposure and well water drinking were significantly associated with PD,
which concluded that environmental factors could act as a risk factor for PD in some way. 相似文献
95.
Ved Prakash Meena V. Seenu M. C. Sharma Saumya Ranjan Mallick Ashu Seith Bhalla Nandita Gupta Anant Mohan Randeep Guleria Ravindra M. Pandey Kalpana Luthra Naval K. Vikram 《PloS one》2014,9(9)
Background
Enlargement of adipocyte is associated with their dysfunction and alterations in metabolic functions.Objectives
We evaluated the association of adipocyte size of subcutaneous and omental adipose tissue with body composition and cardiovascular risk factors in Asian Indians.Methodology
Eighty (40 males and 40 females) non-diabetic adult subjects undergoing elective abdominal surgery were included. Pre-surgery evaluation included anthropometric measurements, % body fat by bioimpedance, abdominal fat area at L2–3 level (computed tomography) and biochemical investigations (fasting blood glucose and insulin, lipids and hsCRP). During surgery, about 5 grams each of omental and subcutaneous adipose tissue was obtained for adipocyte size determination.Results
Females had higher BMI, % body fat, skinfold thickness, total and subcutaneous abdominal fat area as compared to males. Overweight was present in 42.5% and 67.5%, and abdominal obesity in 5% and 52.5% males and females, respectively. Subcutaneous adipocyte size was significantly higher than omental adipocyte size. Omental adipocyte size correlated more strongly than subcutaneous adipocyte size with measures of adiposity (BMI, waist circumference, %BF), total and subcutaneous abdominal fat area and biochemical measures (fasting glucose, total cholesterol, triglycerides and HOMA-IR), the correlations being stronger in females. The correlation of adipocyte size with metabolic parameters was attenuated after adjusting for measures of adiposity.Conclusion
Omental adipocyte size, though smaller than the subcutaneous adipocyte size, was more closely related to measures of adiposity and metabolic parameters. However, the relationship was not independent of measures of adiposity. 相似文献96.
Dipak Banerjee Ramesh C. Upadhyay Umesh B. Chaudhary Ravindra Kumar Sohanvir Singh Ashutosh Jagan Mohanarao G. Shamik Polley Ayan Mukherjee Tapan K. Das Sachinandan De 《Cell stress & chaperones》2014,19(3):401-408
Heat shock protein 70 (HSP70) is one of the most abundant and best characterized heat shock protein family that consists of highly conserved stress proteins, expressed in response to stress, and plays crucial roles in environmental stress tolerance and adaptation. The present study was conducted to identify major types of genes under the HSP70 family and to quantify their expression pattern in heat- and cold-adapted Indian goats (Capra hircus) with respect to different seasons. Five HSP70 gene homologues to HSPA8, HSPA6, HSPA1A, HSPA1L, and HSPA2 were identified by gene-specific primers. The cDNA sequences showed high similarity to other mammals, and proteins have an estimated molecular weight of around 70 kDa. The expression of HSP70 genes was observed during summer and winter. During summer, the higher expression of HSPA8, HSPA6, and HSPA1A was observed, whereas the expression levels of HSPA1L and HSPA2 were found to be lower. It was also observed that the expression of HSPA1A and HSPA8 was higher during winter in both heat- and cold-adapted goats but downregulates in case of other HSPs. Therefore, both heat and cold stress induced the overexpression of HSP70 genes. An interesting finding that emerged from the study is the higher expression of HSP70 genes in cold-adapted goats during summer and in heat-adapted goats during winter. Altogether, the results indicate that the expression pattern of HSP70 genes is species- and breed-specific, most likely due to variations in thermal tolerance and adaptation to different climatic conditions. 相似文献
97.
Association of Rab25 and Rab11a with the Apical Recycling System of Polarized Madin–Darby Canine Kidney Cells 下载免费PDF全文
James E. Casanova Xiaoye Wang Ravindra Kumar Sheela G. Bhartur Jennifer Navarre Julie E. Woodrum Yoram Altschuler Greg S. Ray James R. Goldenring 《Molecular biology of the cell》1999,10(1):47-61
Recent evidence suggests that apical and basolateral endocytic pathways in epithelia converge in an apically located, pericentriolar endosomal compartment termed the apical recycling endosome. In this compartment, apically and basolaterally internalized membrane constituents are thought to be sorted for recycling back to their site of origin or for transcytosis to the opposite plasma membrane domain. We report here that in the epithelial cell line Madin–Darby Canine Kidney (MDCK), antibodies to Rab11a label an apical pericentriolar endosomal compartment that is dependent on intact microtubules for its integrity. Furthermore, this compartment is accessible to a membrane-bound marker (dimeric immunoglobulin A [IgA]) internalized from either the apical or basolateral pole, functionally defining it as the apical recycling endosome. We have also examined the role of a closely related epithelial-specific Rab, Rab25, in the regulation of membrane recycling and transcytosis in MDCK cells. When cDNA encoding Rab25 was transfected into MDCK cells, the protein colocalized with Rab11a in subapical vesicles. Rab25 transfection also altered the distribution of Rab11a, causing the coalescence of immunoreactivity into multiple denser vesicular structures not associated with the centrosome. Nevertheless, nocodazole still dispersed these vesicles, and dimeric IgA internalized from either the apical or basolateral membrane was detected in endosomes labeled with antibodies to both Rab11a and Rab25. Overexpression of Rab25 decreased the rate of IgA transcytosis and of apical, but not basolateral, recycling of internalized ligand. Conversely, expression of the dominant-negative Rab25T26N did not alter either apical recycling or transcytosis. These results indicate that both Rab11a and Rab25 associate with the apical recycling system of epithelial cells and suggest that Rab25 may selectively regulate the apical recycling and/or transcytotic pathways. 相似文献
98.
99.
Kailas D. Sonawane Ravindra Tewari 《Nucleosides, nucleotides & nucleic acids》2013,32(10-11):1158-1174
Conformational preferences of hypermodified nucleoside, 4-amino-2-(N6-lysino)-1-(β-D-ribofuranosyl) pyrimidinium (Lysidine or 2-lysyl cytidine), usually designated as k2C, have been investigated theoretically by the quantum chemical perturbative configuration interaction with localized orbitals (PCILO) method. The zwitterionic, non-zwitterionic, neutral, and tautomeric forms have been studied. Automated geometry optimization using molecular mechanics force field (MMFF), semi-empirical quantum chemical PM3, and ab initio molecular orbital Hartree-Fock SCF quantum mechanical calculations have also been made to compare the salient features. The predicted most stable conformations of zwitterionic, non-zwitterionic, neutral, and tautomeric form are such that in each of these molecules the orientation of lysidine moiety (R) is trans to the N(1) of cytidine. The preferred base orientation is anti (χ = 3°) and the lysine substituent folds back toward the ribose ring. This results in hydrogen bonding between the carboxyl oxygen O(12a) of lysine moiety and the 2′-hydroxyl group of ribose sugar. In all these four forms of lysidine O(12a)…H-C(9) and O(12b)…H-N(11) interactions provide stability to respective stable conformers. Watson-Crick base pairing of lysidine with A is feasible only with the tautomeric form of usual anti oriented lysidine. This can help in recognition of AUA codon besides in avoiding misrecognition of AUG. 相似文献
100.
Crystal structure of a novel prolidase from Deinococcus radiodurans identifies new subfamily of bacterial prolidases 下载免费PDF全文
Venkata N. Are Sahayog N. Jamdar Biplab Ghosh Venuka Durani Goyal Ashwani Kumar Sanchit Neema Rekha Gadre Ravindra D. Makde 《Proteins》2017,85(12):2239-2251
Xaa‐Pro peptidases (XPP) are dinuclear peptidases of MEROPS M24B family that hydrolyze Xaa‐Pro iminopeptide bond with a trans‐proline at the second position of the peptide substrate. XPPs specific towards dipeptides are called prolidases while those that prefer longer oligopeptides are called aminopeptidases P. Though XPPs are strictly conserved in bacterial and archaeal species, the structural and sequence features that distinguish between prolidases and aminopeptidases P are not always clear. Here, we report 1.4 Å resolution crystal structure of a novel XPP from Deinococcus radiodurans (XPPdr). XPPdr forms a novel dimeric structure via unique dimer stabilization loops of N‐terminal domains such that their C‐terminal domains are placed far apart from each other. This novel dimerization is also the consequence of a different orientation of N‐terminal domain in XPPdr monomer than those in other known prolidases. The enzymatic assays show that it is a prolidase with broad substrate specificity. Our structural, mutational, and molecular dynamics simulation analyses show that the conserved Arg46 of N‐terminal domain is important for the dipeptide selectivity. Our BLAST search found XPPdr orthologs with conserved sequence motifs which correspond to unique structural features of XPPdr, thus identify a new subfamily of bacterial prolidases. 相似文献