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991.
992.
Chhana based milk products viz. rossogolla, kanchagolla,
narampak sandesh and karapak sandesh are very popular in eastern part of India and gaining popularity in other parts of the country. A wide variation in manufacture
method, microbial quality and shelf-life of these traditional milk products were observed by previous research. The aim of
the present study was to determine the prevalence of contamination of chhana based milk products available in Kolkata city with Enteropathogenic Escherichia coli (EPEC) serogroups. Random samples of different chhana based milk products were collected from different parts of Kolkata city in aseptic condition, cultured in selective media
and examined for biochemical tests. Among 240 samples, E. coli was isolated from 67 (27.91%) of them. Potential EPEC was present in 52 samples (21.66%) and 55 of the isolates were EPEC.
Eleven serogroups were identified viz. O26, O55, O111, O119, O114, O125, O142, O86, O126, O127, O128. Among all these serogroups,
O55 (23.66%) was the most prevalent. Though recent studies on virulence factors indicate that not all strains serologically
classified as EPEC are able to attaching/effacing lesion, it is believed that the isolation of EPEC serogroups from chhana based milk products represent a potential risk for public health particularly children, as well as an indicative of the presence
of other enteropathogens. Considering the public health importance of sweetmeat consumers, the product should be prepared
hygienically reducing the microbial load present in it. The result indicates that strict preventive measures should be adopted
to ensure contamination free sweetmeats for the safety of the consumers. 相似文献
993.
994.
Puneet Garg Rakesh Verma Leslie Cook Abdul Soofi Madhusudan Venkatareddy Britta George Kensaku Mizuno Christine Gurniak Walter Witke Lawrence B. Holzman 《The Journal of biological chemistry》2010,285(29):22676-22688
Actin dynamics determines podocyte morphology during development and in response to podocyte injury and might be necessary for maintaining normal podocyte morphology. Because podocyte intercellular junction receptor Nephrin plays a role in regulating actin dynamics, and given the described role of cofilin in actin filament polymerization and severing, we hypothesized that cofilin-1 activity is regulated by Nephrin and is necessary in normal podocyte actin dynamics. Nephrin activation induced cofilin dephosphorylation via intermediaries that include phosphatidylinositol 3-kinase, SSH1, 14-3-3, and LIMK in a cell culture model. This Nephrin-induced cofilin activation required a direct interaction between Nephrin and the p85 subunit of phosphatidylinositol 3-kinase. In a similar fashion, cofilin-1 dephosphorylation was observed in a rat model of podocyte injury at a time when foot process spreading is initially observed. To investigate the necessity of cofilin-1 in the glomerulus, podocyte-specific Cfl1 null mice were generated. Cfl1 null podocytes developed normally. However, these mice developed persistent proteinuria by 3 months of age, although they did not exhibit foot process spreading until 8 months, when the rate of urinary protein excretion became more exaggerated. In a mouse model of podocyte injury, protamine sulfate perfusion of the Cfl1 mutant mouse induced a broadened and flattened foot process morphology that was distinct from that observed following perfusion of control kidneys, and mutant podocytes did not recover normal structure following additional perfusion with heparin sulfate. We conclude that cofilin-1 is necessary for maintenance of normal podocyte architecture and for actin structural changes that occur during induction and recovery from podocyte injury. 相似文献
995.
Viprali V Bhatkar Joseph D Skufca Rakesh B Pilkar Christopher M Storey Charles J Robinson 《Biomedical engineering online》2010,9(1):58
Background
A fundamental unsolved problem in psychophysical detection experiments is in discriminating guesses from the correct responses. This paper proposes a coherent solution to this problem by presenting a novel classification method that compares biomechanical and psychological responses. 相似文献996.
Distribution of biogenic amines—the diamine putrescine (Put), triamine spermidine (Spd), and tetraamine spermine (Spm)—differs
between species with Put and Spd being particularly abundant and Spm the least abundant in plant cells. These amines are important
for cell viability and their intracellular levels are tightly regulated, which have made it difficult to characterize individual
effects of Put, Spd and Spm on plant growth and developmental processes. The recent transgenic intervention and mutational
genetics have made it possible to stably alter levels of naturally occurring polyamines and study their biological effects.
We bring together an analysis of certain metabolic changes, particularly in amino acids, to infer the responsive regulation
brought about by increased diamine or polyamine levels in actively growing poplar cell cultures (transformed with mouse ornithine decarboxylase gene to accumulate high Put levels) and ripening tomato pericarp (transformed with yeast S-adenosylmethionine decarboxylase
gene to accumulate high Spd and Spm levels at the cost of Put). Our analysis indicates that increased Put has little effect
on increasing the levels of Spd and Spm, while Spd and Spm levels are inter-dependent. Further, Put levels were positively
associated with Ala (α and β), Ile and GABA and negatively correlated with Gln and Glu in both actively growing poplar cell
cultures and non-dividing tomato pericarp tissue. Most amino acids showed positive correlations with Spd and Spm levels in
actively growing cells. Collectively these results suggest that Put is a negative regulator while Spd–Spm are positive regulators
of cellular amino acid metabolism. 相似文献
997.
Hox genes are necessary for proper morphogenesis and organization of various body structures along the anterior-posterior body axis. These genes exist in clusters and their expression pattern follows spatial and temporal co-linearity with respect to their genomic organization. This colinearity is conserved during evolution and is thought to be constrained by the regulatory mechanisms that involve higher order chromatin structure. Earlier studies, primarily in Drosophila, have illustrated the role of chromatin-mediated regulatory processes, which include chromatin domain boundaries that separate the domains of distinct regulatory features. In the mouse HoxD complex, Evx2 and Hoxd13 are located ~ 9 kb apart but have clearly distinguishable temporal and spatial expression patterns. Here, we report the characterization of a chromatin domain boundary element from the Evx2-Hoxd13 region that functions in Drosophila as well as in mammalian cells. We show that the Evx2-Hoxd13 region has sequences conserved across vertebrate species including a GA repeat motif and that the Evx2-Hoxd13 boundary activity in Drosophila is dependent on GAGA factor that binds to the GA repeat motif. These results show that Hox genes are regulated by chromatin mediated mechanisms and highlight the early origin and functional conservation of such chromatin elements. 相似文献
998.
999.
Naveen C. Srivastav Michelle Mak Babita Agrawal D. Lorne J. Tyrrell Rakesh Kumar 《Bioorganic & medicinal chemistry letters》2010,20(22):6790-6793
Various 2,3′-anhydro analogs of 5-substituted 1-(2-deoxy-β-d-lyxofuranosyl)uracils (10–15) and a related 1-(3-O-mesyl-2-deoxy-β-d-lyxofuranosyl) pyrimidine nucleoside analog (18) have been synthesized for evaluation as a new class of potential anti-HBV agents. The compounds 10, 12, and 15 demonstrated most potent anti-HBV activities against duck HBV (DHBV) and human HBV with EC50 values in the range of 2.5–10 and 5–10 μg/mL, respectively, at non-toxic concentrations (CC50 = >200 μg/mL). The nucleoside 18 also demonstrated significant anti-HBV activity against DHBV with an EC50 value of 2.5 μg/mL, however, it was less active against HBV in 2.2.15 cells (EC50 = >10 μg/mL). 相似文献
1000.
Hong Lin Dennis S. Yamashita Jin Zeng Ren Xie Sharad Verma Juan I. Luengo Nelson Rhodes Shuyun Zhang Kimberly A. Robell Anthony E. Choudhry Zhihong Lai Rakesh Kumar Elisabeth A. Minthorn Kristin K. Brown Dirk A. Heerding 《Bioorganic & medicinal chemistry letters》2010,20(2):679-683
A novel series of AKT inhibitors containing 2,3,5-trisubstituted pyridines with novel azaindazoles as hinge binding elements are described. Among these, the 4,7-diazaindazole compound 2c has improved drug-like properties and kinase selectivity than those of indazole 1, and displays greater than 80% inhibition of GSK3β phosphorylation in a BT474 tumor xenograft model in mice. 相似文献