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41.
Chada Raji Reddy Amol Gorgile Tukaram Siddique Z. Mohammed Uredi Dilipkumar Bathini Nagendra Babu Sumana Chakravarty Dwaipayan Bhattacharya Pranav C. Joshi René Grée 《Bioorganic & medicinal chemistry letters》2018,28(4):673-676
Longanlactone analogues were synthesized using a route featuring Friedel-Crafts acylation, Sonogashira coupling and 1,3-dipolar cycloaddition reactions. Structure–activity relationships were investigated for neurotrophic activity. Compound 6 was found to have the most potent neurotrophic activity among all the synthesized analogues in Neuro2a cells as evidenced by a battery of in vitro/cell based assays for assessment of neurogenic and potential neurotrophic activity including neurite outgrowth assay and real time PCR for popular markers of augmented neurotrophic activity. Compound 6 might serve as a template for further development of highly effective neurotrophic molecules. 相似文献
42.
Bandyopadhyay Arindam Garai Saraswati Banerjee Prajna Paramita Bhattacharya Shelley Chattopadhyay Ansuman 《Molecular biology reports》2021,48(3):2497-2505
Molecular Biology Reports - Globally, breast cancer is a serious concern that exhibits a persistent rise in its incidence and related mortality even after significant advancement in the field of... 相似文献
43.
R. J. Bellamy C. F. Inglehearn I. K. Jalili A. J. Jeffreys S. S. Bhattacharya 《Human genetics》1991,87(3):341-347
Summary We have compared band sharing between the DNA fingerprints of members of an inbred human population with band sharing between members of an outbred population. It had not previously been determined whether the high rate of mutation at minisatellite loci is sufficient to prevent an increase in band sharing in moderately inbred populations. We have found that there is an increase in band sharing in the 2-kb to 9-kb size range, but not in the >9-kb size range, in the inbred population. The difference was consistently observed using four different multi-locus probes, viz. 33.6, 33.15, (CAC)5 and M13. Thus, we have demonstrated that moderate but prolonged inbreeding can lead to increased similarity in human DNA fingerprints. This should be considered when analysing DNA fingerprints in forensic or paternity cases involving members of an inbred community. 相似文献
44.
45.
BACKGROUND AND AIMS: The aim of this study was to develop species-specific molecular markers for Bambusa balcooa and B. tulda to allow for their proper identification, in order to avoid unintentional adulteration that affects the quality and quantity of paper pulp production. METHODS: Two putative, species-specific RAPD markers, Bb836 for B. balcooa and Bt609 for B. tulda were generated using a PCR-based RAPD technique. Species-specificity of these two markers was confirmed through Southern hybridization in which RAPD gels were blotted and hybridized with radiolabelled cloned RAPD markers. Southern hybridization analyses were also performed to validate homology of the co-migrating Bb836 and Bt609 marker bands amplified from 16 different populations of B. balcooa and B. tulda, respectively. Sequence-characterized amplified region (SCAR) markers were developed from Bb836 and Bt609 sequences, using 20-mer oligonucleotide primers designed from both the flanking ends of the respective RAPD primers. KEY RESULTS: As anticipated, Bb836 hybridized with an amplified band from B. balcooa and Bt609 hybridized only with an amplified product from B. tulda; the two markers did not hybridize with the amplified products of any of the other 14 bamboo species studied. The two pairs of SCAR primers amplified the target sequences only in the respective species. The species-specific SCAR fragments were named as 'Balco836' for B. balcooa and 'Tuldo609' for B. tulda. The species-specific 'Balco836' was amplified from the genomic DNA of 80 individuals of 16 populations of B. balcooa studied. Similarly, the presence of 'Tuldo609' was noted in all the 80 individuals representing 16 populations of B. tulda assessed. These SCAR fragments contained no obvious repetitive sequence beyond the primers. CONCLUSION: These two molecular markers are potentially useful for regulatory agencies to establish sovereign rights of the germplasms of B. balcooa and B. tulda. In addition, this is the first report of species-specific SCAR marker development in bamboo. 相似文献
46.
A series of 5-arylidene-2,4-thiazolidinediones and its geranyloxy or prenyloxy derivative were synthesized and studied for their radical scavenging activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Their comparable scavenging activities were expressed as IC50 value. Compounds 2c, 2d, 4d, and 6a showed appreciable radical scavenging activities. The vanillin based thiazolidinedione compound 2c displayed highest activity comparable to that of alpha-tocopherol. But in vivo, compound 6a showed better results in inducing phase II detoxifying/antioxidative enzyme. 相似文献
47.
Suman Kanungo Bandana Sen Thandavarayan Ramamurthy Dipika Sur Byomkesh Manna Gururaja P. Pazhani Goutam Chowdhury Puja Jhunjhunwala Ranjan K. Nandy Hemanta Koley Mihir Kumar Bhattacharya Sanjay Gupta Gaurav Goel Bindu Dey Thungapathra M G. Balakrish Nair Amit Ghosh Dilip Mahalanabis 《PloS one》2014,9(7)
Background
A live oral cholera vaccine VA 1.4 developed from a non-toxigenic Vibrio cholerae O1 El Tor strain using ctxB gene insertion was further developed into a clinical product following cGMP and was evaluated in a double-blind randomized placebo controlled parallel group two arm trial with allocation ratio of 1∶1 for safety and immunogenicity in men and women aged 18–60 years from Kolkata, India.Method
A lyophilized dose of 1.9×109 CFU (n = 44) or a placebo (n = 43) reconstituted with a diluent was administered within 5 minutes of drinking 100 ml of a buffer solution made of sodium bicarbonate and ascorbic acid and a second dose on day 14.Result
The vaccine did not elicit any diarrhea related adverse events. Other adverse events were rare, mild and similar in two groups. One subject in the vaccine group excreted the vaccine strain on the second day after first dose. The proportion of participants who seroconverted (i.e. had 4-folds or higher rise in reciprocal titre) in the vaccine group were 65.9% (95% CI: 50.1%–79.5%) at both 7 days (i.e. after 1st dose) and 21 days (i.e. after 2nd dose). None of the placebo recipients seroconverted. Anti-cholera toxin antibody was detected in very few recipients of the vaccine.Conclusion
This study demonstrates that VA 1.4 at a single dose of 1.9×109 is safe and immunogenic in adults from a cholera endemic region. No additional benefit after two doses was seen.Trial Registration
Clinical Trials Registry-India, National Institute of Medical Statistics (Indian Council of Medical Research) CTRI/2012/04/002582 相似文献48.
Amita?Bhattacharya P.?K.?NagarEmail author Paramvir?Singh?Ahuja 《Acta Physiologiae Plantarum》2004,26(4):399-404
The role of endogenous indole-3-acetic acid (IAA), soluble proteins and RNA in the development of tea (Camellia sinensis (L). O. Kuntze) seeds was investigated in the present study. The state of continuum even at full maturity and lack of a clear
end point to seed development as indicated by the persistence of appreciable contents of proteins at full maturity in all
the seed parts further confirmed the ‘recalcitrant nature’ of the tea seeds. Unlike the orthodox seeds, the level of free
IAA in tea embryos also remained high even at full maturity. The total RNA content remained high in the stages with high moisture
content but declined with progressive decline in moisture content. 相似文献
49.
Sayed Sartaj Sohrab Esam I. Azhar Mohammad A. Kamal P.S. Bhattacharya D. Rana 《Saudi Journal of Biological Sciences》2014,21(6):626-631
Cotton is an important crop and its production is affected by various disease pathogens. Monopartite begomovirus associated betasatellites cause Cotton leaf curl disease (CLCuD) in Northern India. In order to access the occurrence and genetic variability of Cotton leaf curl betasatellites, an extensive field survey was conducted in states of Rajasthan, Punjab and Haryana. We selected the betasatellite sequence for analysis as they are reported as important for disease severity and sequence variability. Based on the field observations, the disease incidence ranged from 30% to 80% during the survey. Full genome and DNA β were amplified from various samples while no amplicon was obtained in some samples. The nucleotide sequence homology ranged from 90.0% to 98.7% with Cotton leaf curl virus (CLCuV), 55.2–55.5% with Bhendi yellow vein mosaic virus, 55.8% with Okra leaf curl virus and 51.70% with Tomato leaf curl virus isolates. The lowest similarity (47.8%) was found in CLCuV-Sudan isolate. Phylogenetic analysis showed that analyzed isolates formed a close cluster with various CLCuV isolates reported earlier. The analysis results show sequence variation in Cotton leaf curl betasatellite which could be the result of recombination. The results obtained by genome amplification and sequence variability indicate that some new variants are circulating and causing leaf curl disease in Rajasthan, Punjab and Haryana.Abbreviations: CLCuD, Cotton leaf curl disease; CLCuV, Cotton leaf curl virus; PCR, polymerase chain reaction; SCR, satellite conserved region 相似文献
50.
Subarna Bhattacharya Paul W. Burridge Erin M. Kropp Sandra L. Chuppa Wai-Meng Kwok Joseph C. Wu Kenneth R. Boheler Rebekah L. Gundry 《Journal of visualized experiments : JoVE》2014,(91)
There is an urgent need to develop approaches for repairing the damaged heart, discovering new therapeutic drugs that do not have toxic effects on the heart, and improving strategies to accurately model heart disease. The potential of exploiting human induced pluripotent stem cell (hiPSC) technology to generate cardiac muscle “in a dish” for these applications continues to generate high enthusiasm. In recent years, the ability to efficiently generate cardiomyogenic cells from human pluripotent stem cells (hPSCs) has greatly improved, offering us new opportunities to model very early stages of human cardiac development not otherwise accessible. In contrast to many previous methods, the cardiomyocyte differentiation protocol described here does not require cell aggregation or the addition of Activin A or BMP4 and robustly generates cultures of cells that are highly positive for cardiac troponin I and T (TNNI3, TNNT2), iroquois-class homeodomain protein IRX-4 (IRX4), myosin regulatory light chain 2, ventricular/cardiac muscle isoform (MLC2v) and myosin regulatory light chain 2, atrial isoform (MLC2a) by day 10 across all human embryonic stem cell (hESC) and hiPSC lines tested to date. Cells can be passaged and maintained for more than 90 days in culture. The strategy is technically simple to implement and cost-effective. Characterization of cardiomyocytes derived from pluripotent cells often includes the analysis of reference markers, both at the mRNA and protein level. For protein analysis, flow cytometry is a powerful analytical tool for assessing quality of cells in culture and determining subpopulation homogeneity. However, technical variation in sample preparation can significantly affect quality of flow cytometry data. Thus, standardization of staining protocols should facilitate comparisons among various differentiation strategies. Accordingly, optimized staining protocols for the analysis of IRX4, MLC2v, MLC2a, TNNI3, and TNNT2 by flow cytometry are described. 相似文献