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11.
Kotakonda Arunasri Mohammed Adil Katari Venu Charan Chatterjee Suvro Seerapu Himabindu Reddy Sisinthy Shivaji 《PloS one》2013,8(3)
This study demonstrates the effects of simulated microgravity on E. coli K 12 MG1655 grown on LB medium supplemented with glycerol. Global gene expression analysis indicated that the expressions of hundred genes were significantly altered in simulated microgravity conditions compared to that of normal gravity conditions. Under these conditions genes coding for adaptation to stress are up regulated (sufE and ssrA) and simultaneously genes coding for membrane transporters (ompC, exbB, actP, mgtA, cysW and nikB) and carbohydrate catabolic processes (ldcC, ptsA, rhaD and rhaS) are down regulated. The enhanced growth in simulated gravity conditions may be because of the adequate supply of energy/reducing equivalents and up regulation of genes involved in DNA replication (srmB) and repression of the genes encoding for nucleoside metabolism (dfp, pyrD and spoT). In addition, E. coli cultured in LB medium supplemented with glycerol (so as to protect the cells from freezing temperatures) do not exhibit multiple stress responses that are normally observed when cells are exposed to microgravity in LB medium without glycerol. 相似文献
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Preparation and in vitro evaluation of xanthan gum facilitated superabsorbent polymeric microspheres
Shiv Sankar Bhattacharya Farhan Mazahir Subham Banerjee Anurag Verma Amitava Ghosh 《Carbohydrate polymers》2013
Interpenetrating polymer network (IPN) hydrogel microspheres of xanthan gum (XG) based superabsorbent polymer (SAP) and poly(vinyl alcohol) (PVA) were prepared by water-in-oil (w/o) emulsion crosslinking method for sustained release of ciprofloxacin hydrochloride (CIPRO). The microspheres were prepared with various ratios of hydrolyzed SAP to PVA and extent of crosslinking density. The prepared microspheres with loose and rigid surfaces were evidenced by scanning electron microscope (SEM). Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis confirmed the IPN formation. Differential scanning calorimetry (DSC) study was performed to understand the dispersion nature of drug after encapsulation. The in vitro drug release study was extensively evaluated depending on the process variables in both acidic and alkaline media. All the formulations exhibited satisfactory physicochemical and in vitro release characteristics. Release data indicated a non-Fickian trend of drug release from the formulations. Based on the results, this study suggest that CIPRO loaded IPN microspheres were suitable for sustained release application. 相似文献
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Pandey Shiv S. Singh Sucheta Babu C. S. Vivek Shanker Karuna Srivastava N. K. Kalra Alok 《Planta》2016,243(5):1097-1114
Planta - Endophytes reside in different parts of the poppy plant and perform the tissue-specific functions. Most leaf endophytes modulate photosynthetic efficiency, plant growth, and productivity... 相似文献
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The multivariate statistical methods (cluster analysis and discriminant analysis [DA]) are used to evaluate the quality of water spatiotemporally in the Brahmani River basin. A total of 15 water quality indicators (pH, Chloramines, Sodium, Sulfate, Phosphate, Potassium, Boron, Fluoride, Cadmium, Copper, Lead, Nickel, Zinc, Iron, and Total Chromium) are collected for 13 years in two seasons (the dry and the wet season) from nine sampling stations. These stations are grouped into four clusters (Considerable [Co], Low Pollution [LP], Moderate Pollution [MP], and Extreme Pollution [(EP]) by hierarchical agglomerative cluster analysis based on the similarities of water quality characteristics. The nine important influencing discriminating water quality indicators are extracted by stepwise method of temporal DA,where as eight important influencing indicators for dry season and eight indicators (Potassium, Phosphate, Fluoride, Copper, Lead, Nickel, Iron, and Total Chromium) for wet season are found out by the spatial DA. The pollution status in the river basin was observed from overall trend in (Considerable) Co to (Extreme Pollution) EP regions. The study could be very useful in prioritizing the important sites for water resources and pollution management. 相似文献
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Chitinase-mediated inhibitory activity of Brassica transgenic on growth of Alternaria brassicae 总被引:1,自引:0,他引:1
Mondal KK Chatterjee SC Viswakarma N Bhattacharya RC Grover A 《Current microbiology》2003,47(3):171-173
Chitinase, capable of degrading the cell walls of invading phytopathogenic fungi, plays an important role in plant defense response, particularly when this enzyme is overexpressed through genetic engineering. In the present study, Brassica plant (Brassica juncea L.) was transformed with chitinase gene tagged with an overexpressing promoter 35 S CaMV. The putative transgenics were assayed for their inhibitory activity against Alternaria brassicae, the inducer of Alternaria leaf spot of Brassica both in vitro and under polyhouse conditions. In in vitro fungal growth inhibition assays, chitinase inhibited the fungal colony size by 12-56% over the non-trangenic control. The bioassay under artificial epiphytotic conditions revealed the delay in the onset of disease as well as reduced lesion number and size in 35S-chitinase Brassica as compared to the untransformed control plants. 相似文献
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Cariappa A Chen L Haider K Tang M Nebelitskiy E Moran ST Pillai S 《Journal of immunology (Baltimore, Md. : 1950)》2003,171(4):1875-1880
Protein kinase C-associated kinase (PKK)/receptor interacting protein 4 (RIP4) is a protein kinase C (PKC) beta-associated kinase that links PKC to NF-kappaB activation. The kinase domain of PKK is similar to that of RIP, RIP2, and RIP3. We show in this study that PKK is expressed early during lymphocyte development and can be detected in common lymphoid progenitor cells. Targeting of a catalytically inactive version of PKK to lymphoid cells resulted in a marked impairment in pro-B cell generation in the bone marrow. Although peripheral B cell numbers were markedly reduced, differentiation into follicular and marginal zone B cells was not defective in these mice. B-1a and B-1b B cells could not be detected in these mice, but this might be a reflection of the overall defect in B cell production observed in these animals. In keeping with a possible link to PKCbeta, peripheral B cells in these mice exhibit a defect in anti-IgM-mediated proliferation. These studies suggest that PKK may be required early in B cell development and for BCR-mediated B cell proliferation. 相似文献
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Dipivaloyl-5-carboxyfluorescein N-hydroxysuccinimidyl ester 1 and 5-propargylamino-2',3'-dideoxyuridine triphosphate 5 were modified with maleimide, haloacetamide, and sulfhydryl reactive functional groups to participate in cross-conjugation reactions via sulfide bonds to generate fluorescently labeled, thioether cross-conjugated terminators 10 and 11. Their DNA sequencing potential was compared with an amide cross-conjugated terminator 13, synthesized by directly coupling 5-carboxyfluorescein NHS ester with 18-ddUTP 9. These terminators (10, 11, and 13) in combination with the Thermo Sequenase II DNA polymerase, in thermal cycle sequencing experiments, revealed that the thioether cross-conjugated terminator 10 and amide cross-conjugated terminator 13 served as good terminating substrates, generating satisfactory single-color gel images and electropherograms, while the other thioether cross-conjugated and maleimide derived one 11 underwent unexpected pH and temperature induced decomposition without showing fluorescent signatures for incorporation. 相似文献