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51.
52.
Saha A Deb R Shah S Ramamurthy T Shinoda S Mukhophadyay AK Bhadra RK 《FEMS microbiology letters》2006,257(1):84-91
The bacterial chromosomal replication origin (ori) sequences are a highly conserved essential genetic element. In this study, the large chromosomal replication origin sequence of Vibrio cholerae (oriCIVC) has been targeted for identification of the organism, including the biotypes of serogroup O1. The oriCIVC sequence-based PCR assay specifically amplified an 890 bp fragment from all the V. cholerae strains examined. A point mutation in the oriCIVC sequence of the classical biotype of O1 serogroup led to the loss of a BglII site, which was utilized for differentiation from El Tor vibrios. Interestingly, the PCR assay amplified a similarly sized ori segment, designated as oriCIVM, from V. mimicus strains, but failed to produce any amplicon with other strains. Cloning and sequencing of the oriCIVM revealed high sequence similarity (96%) with oriCIVC. The results indicate that V. mimicus is indeed very closely related to V. cholerae. In addition, the BglII restriction fragment length polymorphism (RFLP) between oriCIVM and oriCIVC sequences allowed us to differentiate the two species. The ori sequence-based PCR-RFLP assay developed in this study appears to be a useful method for rapid identification and differentiation of V. cholerae and V. mimicus strains, as well as for the delineation of classical and El Tor biotypes of V. cholerae O1. 相似文献
53.
In vitro mass production of C. suaveolens (Lindl.) Hook, an endangered orchid with its snowy white flowers having horticultural potential was accomplished through immature seed culture, and subsequent plant regeneration. The developmental stage of the immature seeds and nutrient media significantly influenced the germination frequency. Seeds at 13 months after pollination cultured on 3% sucrose containing Murashige and Skoog (MS) medium with 9 microM alpha-naphthaleneacetic acid (NAA), and 15% coconut water exhibited 93% germination after 40 days of culture. Upon subculture, the germinated shoots on MS medium with 9 microM BA, 6 microM NAA, 3% casein hydrolysate and 0.1% activated charcoal (AC) yielded >12 shoots per shoot or bud. Addition of AC favoured the enlargement of pseudobulbs and better rooting. The plantlets transferred to community potting mix after in vitro hardening (8-10 wk) displayed 85% survival. 相似文献
54.
Kavitha Sivasubramaiyan Swapnil Totey Vijay Bhat Satish M Totey Kaushik Deb 《Journal of biomedical science》2009,16(1):88-9
Trophoblast differentiation and formation of the placenta are important events linked to post-implantation embryonic development.
Models mimicking the biology of trophoblast differentiation in a post-implantation maternal microenvironment are needed for
understanding disorders like placental-ischemia or for applications in drug-screening, and would help in overcoming the ethical
impasse on using human embryos for such research. Here we attempt to create such a model by using embryoid bodies (EBs) and
a biomimetic platform composed of a bilayer of fibronectin and gelatin on top of low-melting agarose. Using this model we
test the hypothesis that cystic-EBs (day 30) that resemble blastocysts morphologically, are better sources as compared to
noncytic EBs (day 10), for functional trophoblast differentiation; and that the Rho kinases inhibitor Y27632 can enhance this
differentiation. Non/cytic EBs with/out Y27632 were grown on this platform for 28 days, and screened from secretion and expression
of trophoblast and other lineage markers using ECLIA, RT-PCR, and Immunofluorescence. All EBs attached on this surface and
rapidly proliferated into hCG and progesterone (P2) secreting functional trophoblast cells. However, the cells derived from
cytic-EBs and cytic-EBs+ Y27632 showed the maximum secretion of these hormones and expressed IGF2, supporting our hypothesis.
Also Y27632 reduced extraembryonic endoderm and trophoblast lineage differentiation from early noncystic-EBs, whereas, it
specifically enhanced the induction of trophoblast and multinucleated syncitiotrophoblast differentiation from late cystic-EBs.
In vivo trophoblast differentiation can be replicated in fibronectin based biomaterials, using cytic-EBs and by maneuvering the Rho-ROCK
pathways. Response of EBs to a compound may vary temporally, and determination of their right stage is crucial for applications
in directed-differentiation or drug-screening. 相似文献
55.
Ishani Deb Priyankar Paira Abhijit Hazra Sukdeb Banerjee Pradip Kumar Dutta Nirup Bikash Mondal Sumantra Das 《Bioorganic & medicinal chemistry》2009,17(16):5782-5790
Based on an established 3D pharmacophore, a series of quinoline derivatives were synthesized. The opioidergic properties of these compounds were determined by a competitive binding assay using 125I-Dynorphine, 3H-DAMGO and 125I-DADLE for κ, μ, and δ receptors, respectively. Results showed varying degree of activities of the compounds to κ and μ opioid receptors with negligible interactions at the δ receptor. The compound, S4 was the most successful in inhibiting the two most prominent quantitative features of naloxone precipitated withdrawal symptoms - stereotyped jumping and body weight loss. Determination of IC50 of S4 revealed a greater affinity towards μ compared to κ receptor. In conclusion, quinoline derivatives of S4 like structure offer potential tool for treatment of narcotic addictions. 相似文献
56.
Dendrobium primulinum is an important epiphytic orchid. A successful protocol for mass multiplication and early in vitro flowering was developed. Immature embryos of 4 week after pollination exhibited about 96% germination within 30 days of culture on MS medium containing sucrose (3%) (w/v), NAA and BA (6 and 9 μM) in combination. Protocorm-like bodies (PLBs) formed from the germinating seeds on the germination medium. Rooted plantlets were formed within 2-3 wk on MS medium containing sucrose (3%), NAA and BA (3 and 12 μM in combination) where about 29 shoot/buds produced per cycle of 4 wk interval. The well rooted plantlets produced 4-5 floral buds per spike when they were maintained on MS medium containing sucrose (3%), fresh apple juice (10%) (v/v) for four wk followed by on MS medium freed of apple juice but enriched with NAA and BA (3 and 12 μM respectively). The hardened plantlets were transferred to community potting mix where the about 80% transplants survived after two months of transfer. 相似文献
57.
Bulbul Chakravarti Dr. Beerelli Seshi Wongrat Ratanaprayul Neville Dalal Lawrence Lin Alpan Raval Deb N. Chakravarti 《Proteomics》2009,9(3):580-597
Aging is a time‐dependent complex biological phenomenon observed in various organs and organelles of all living organisms. To understand the molecular mechanism of age‐associated functional loss in aging kidneys, we have analyzed the expression of proteins in the kidneys of young (19–22 wk) and old (24 months) C57/BL6 male mice using 2‐DE followed by LC‐MS/MS. We found that expression levels of 49 proteins were upregulated (p ≤ 0.05), while that of only ten proteins were downregulated (p ≤ 0.05) due to aging. The proteins identified belong to three broad functional categories: (i) metabolism (e.g., aldehyde dehydrogenase family, ATP synthase β‐subunit, malate dehydrogenase, NADH dehydrogenase (ubiquinone), hydroxy acid oxidase 2), (ii) transport (e.g., transferrin), and (iii) chaperone/stress response (e.g., Ig‐binding protein, low density lipoprotein receptor‐related protein associated protein 1, selenium‐binding proteins (SBPs)). Some proteins with unknown functions were also identified as being differentially expressed. ATP synthase β subunit, transferrin, fumarate hydratase, SBPs, and albumin are present in multiple forms, possibly arising due to proteolysis or PTMs. The above functional categories suggest specific mechanisms and pathways for age‐related kidney degeneration. 相似文献
58.
The soluble expression of heterologous proteins in Escherichia coli remains a serious bottleneck in protein production. Although alteration of expression conditions can sometimes solve the problem, the best available tools to date have been fusion tags that enhance the solubility of expressed proteins. However, a systematic analysis of the utility of these solubility fusions has been difficult, and it appears that many proteins react differently to the presence of different solubility tags. The advent of high-throughput structural genomics programs and advances in cloning and expression technology afford us a new way to compare the effectiveness of solubility tags. This data should allow us to better predict the effectiveness of tags currently in use, and might also provide the information needed to identify new fusion tags. 相似文献
59.
Ankita Deb Bhavana Deshmukh Pranay Ramteke Firoz Khan Bhati Manoj Kumar Bhat 《Translational oncology》2021,14(10)
Resistin, a small secretory molecule, has been implicated to play an important role in the development of insulin resistance under obese condition. For the past few decades, it has been linked to various cellular and metabolic functions. It has been associated with diseases like metabolic disorders, cardiovascular diseases and cancers. Numerous clinical studies have indicated an increased serum resistin level in pathological disorders which have been reported to increase mortality rate in comparison to low resistin expressing subjects. Various molecular studies suggest resistin plays a pivotal role in proliferation, metastasis, angiogenesis, inflammation as well as in regulating metabolism in cancer cells. Therefore, understanding the role of resistin and elucidating its’ associated molecular mechanism will give a better insight into the management of these disorders. In this article, we summarize the diverse roles of resistin in pathological disorders based on the available literature, clinicopathological data, and a compiled study from various databases. The article mainly provides comprehensive information of its role as a target in different treatment modalities in pre as well as post-clinical studies. 相似文献
60.