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81.
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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   
83.
A novel series of l-tyrosine derivatives have been reported with potential PPARalpha/gamma dual agonistic activity. In vitro cell based PPARalpha/gamma transactivation studies have shown compound 4a and compound 4f to be the most potent PPARgamma and PPARalpha activators, respectively. Molecular docking studies performed on these series of compounds have complemented the experimental results and have led to interesting inferences.  相似文献   
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Background  

The alterations in skeletal muscle structure and function after prolonged periods of unloading are initiated by the chronic lack of mechanical stimulus of sufficient intensity, which is the result of a series of biochemical and metabolic interactions spanning from cellular to tissue/organ level. Reduced activation of skeletal muscle alters the gene expression of myosin heavy chain isoforms to meet the functional demands of reduced mechanical load, which results in muscle atrophy and reduced capacity to process fatty acids. In contrast, chronic loading results in the opposite pattern of adaptations.  相似文献   
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DNA replication, repair, and recombination (DRRR) are the fundamental processes required for faithful transmission of genetic information within and between generations. The DRRR genes protect the cells from potential mutations and damage during the developmental phases and stress conditions. Thus, these genes indirectly regulate diverse important agronomic traits in a crop plant. A genome-wide survey of six DRRR pathway genes, namely, DNA replication, Base Excision Repair, Nucleotide Excision Repair, Homologous Recombination, Mismatch Excision Repair, and Non-Homologous End-Joining, identified 157 DRRR genes in chickpea. Phylogenetic analysis of these genes within the legume clades and model plant Arabidopsis identified 42 conserved DRRR genes exhibiting clade-specific evolutionary patterns. Integrating the gene-based association mapping with differential expression profiling identified the natural alleles of the potential DRRR genes, primarily regulating flowering and maturation time and involved in drought tolerance of chickpea. Identifying and understanding DRRR genes’ roles in regulating yield and stress tolerance traits in a vital grain legume like chickpea is requisite for its future crop improvement endeavors. Manipulation of promising functionally relevant DRRR genes will pave the way for simultaneous improvement in multiple beneficial agronomic traits in chickpea.

  相似文献   
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Intestinal parasitic infections are one of the major causes of diarrhea in human immunodeficiency virus (HIV) seropositive individuals. Antiretroviral therapy has markedly reduced the incidence of many opportunistic infections, but parasite-related diarrhea still remains frequent and often underestimated especially in developing countries. The present hospital-based study was conducted to determine the spectrum of intestinal parasitosis in adult HIV/AIDS (acquired immunodeficiency syndrome) patients with or without diarrhea with the levels of CD4+ T-cell counts. A total of 400 individuals were enrolled and were screened for intestinal parasitosis. Of these study population, 200 were HIV seropositives, and the remaining 200 were HIV uninfected individuals with or without diarrhea. Intestinal parasites were identified by using microscopy as well as PCR assay. A total of 130 (32.5%) out of 400 patients were positive for any kinds of intestinal parasites. The cumulative number of parasite positive patients was 152 due to multiple infections. A significant association of Cryptosporidium (P<0.001) was detected among individuals with CD4+ T-cell counts less than 200 cells/μl.  相似文献   
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