Investigation of tuberculosis clusters in Dehradun city of India

ObjectiveTo investigate the presence of statistically significant geographical clusters of tuberculosis (TB) using Geographical Information System and spatial scan statistics in Dehradun, India.MethodsThe spatial scan statistic implemented with a software program, SaTScan v6.1, was used to test the presence of statistically significant spatial clusters of TB and to identify their approximate locations (P< 0.05 for primary clusters and P<0.1 for secondary clusters). Geographical Information System was used for geographical analysis.ResultsSignificant high rate spatial clusters were identified in seven wards of the Dehradun Municipal area.ConclusionsThere is sufficient evidence about the existence of statistically significant TB clusters in seven wards of Dehradun, India. The purely spatial scan statistics methodology used in this study has a potential use in surveillance of TB for detecting the true clusters of the disease.     

Safety and immunogenicity of the intradermal Thai red cross (2-2-2-0-1-1) post exposure vaccination regimen in the Indian population using purified chick embryo cell rabies vaccine

Purpose: To test the immunogenicity of the WHO recommended “2-2-2-0-1-1” post-exposure rabies vaccination regimen in Indian subjects to determine the feasibility of replacing crude sheep brain nerve tissue rabies vaccine with modern tissue culture rabies vaccine at major anti-rabies treatment centers throughout India. Methods: Purified chick embryo cell vaccine (PCECV) was administered in the dosage of 0.1mL per site to 53 Indian subjects. Results: All subjects produced rabies antibodies above 0.5IU/mL by day 14 post-vaccination. Only minor adverse reactions including swelling (6.6%), erythema (5.4%) and pain (1.4%) were observed for which no treatment was required. Conclusions: This study demonstrated that PCECV is safe and highly immunogenic in Indian subjects when administered intradermally as 0.1mL/site using the “2-2-2-0-1-1” post-exposure regimen.     

Characterization of Protective Epitopes in a Highly Conserved Plasmodium falciparum Antigenic Protein Containing Repeats of Acidic and Basic Residues

The delineation of putatively protective and immunogenic epitopes in vaccine candidate proteins constitutes a major research effort towards the development of an effective malaria vaccine. By virtue of its role in the formation of the immune clusters of merozoites, its location on the surface of merozoites, and its highly conserved nature both at the nucleotide sequence level and the amino acid sequence level, the antigen which contains repeats of acidic and basic residues (ABRA) of the human malaria parasite Plasmodium falciparum represents such an antigen. Based upon the predicted amino acid sequence of ABRA, we synthesized eight peptides, with six of these (AB-1 to AB-6) ranging from 12 to 18 residues covering the most hydrophilic regions of the protein, and two more peptides (AB-7 and AB-8) representing its repetitive sequences. We found that all eight constructs bound an appreciable amount of antibody in sera from a large proportion of P. falciparum malaria patients; two of these peptides (AB-1 and AB-3) also elicited a strong proliferation response in peripheral blood mononuclear cells from all 11 human subjects recovering from malaria. When used as carrier-free immunogens, six peptides induced a strong, boostable, immunoglobulin G-type antibody response in rabbits, indicating the presence of both B-cell determinants and T-helper-cell epitopes in these six constructs. These antibodies specifically cross-reacted with the parasite protein(s) in an immunoblot and in an immunofluorescence assay. In another immunoblot, rabbit antipeptide sera also recognized recombinant fragments of ABRA expressed in bacteria. More significantly, rabbit antibodies against two constructs (AB-1 and AB-5) inhibited the merozoite reinvasion of human erythrocytes in vitro up to ~90%. These results favor further studies so as to determine possible inclusion of these two constructs in a multicomponent subunit vaccine against asexual blood stages of P. falciparum.     

Evaluation of antimicrobial activity and bronchodialator effect of a polyherbal drug-Shrishadi

Objective

To investigate antimicrobial and bronchodialator effect of hydroalcholic extract of polyherbal drug Shirishadi containing Shirisha (Albezzia lebbeck), Nagarmotha (Cyprus rotandus) & Kantakari (Solanum xanthocarpum).

Methods

Antimicrobial activity was evaluated by disc diffusion method and MIC, MBC, MFC were calculated by micro dilution method. Hydroalcholic extract of this preparation was investigated for its phytochemical analysis, phenol and flavonoid were determined by spectrophotometric method and in vivo bronchodilator effect was analysed by convulsion time.

Results

The phytochemical tests revealed presence of alkaloids, anthraquinones, carbohydrates, flavonoids, saponins and tannins. The antimicrobial result showed the MIC of 6.25 mg/mL against Staphylococcus aureus and 12.5 mg/mL for Escherichia coli and 12.5 mg/mL against remaining bacteria tested, with strong antifungal activity. The maximum inhibition zone is found against Pseudomonas aeruginosa with MIC 16 mg/mL. Drug showed significant bronchodilator effect with 27.86% & 36.13% increase in preconvulsion time of guinea pigs pretreated with 100 & 200 mg/kg body weight of extract.

Conclusions

The study reveals that the extracts possess antibacterial activity and antifungal activity in a dose dependent manner. This antimicrobial property may be due to presence of several saponins, further studies are highly needed for the drug development.     

Validated gradient stability indicating HPLC method for determining Diltiazem Hydrochloride and related substances in bulk drug and novel tablet formulation

A stability-indicating liquid chromatographic method has been developed and validated for the determination of Diltiazem Hydrochloride (DTZ) together with its six related substances (Diltiazem sulphoxide, Imp-A, Imp-B, Imp-D, Imp-E, and Imp-F) in a laboratory mixture as well as in a novel tablet formulation developed in-house. Efficient chromatographic separation was achieved on a Hypersil BDS C₁₈ (150 mm×4.6 mm, 5.0 μm) with mobile phase containing 0.2% Triethylamine (TEA) in gradient combination with acetonitrile (ACN) at a flow rate of 1.0 mL/min and the eluent was monitored at 240 nm. In the developed method, the resolution of DTZ from any pair of impurities was found to be greater than 2.0. The test solution and related substances were found to be stable in the diluent for 24 h. The developed method resolved the drug from its known impurities, stated above, and also from additional impurities generated when the formulation was subjected to forced degradation; the mass balance was found close to 99.9%.Regression analyses indicate correlation coefficient value greater than 0.997 for DTZ and its six known impurities. The LOD for DTZ and the known impurities was at a level below 0.02%. The method has shown good, consistent recoveries for DTZ (99.8–101.2%) and also for its six known impurities (97.2–101.3%). The method was found to be accurate, precise, linear, specific, sensitive, rugged, robust, and stability-indicating.     

Temporal changes of particulate concentration in the ambient air over the city of Zahedan, Iran

Air pollution in developing countries has recently become a serious environmental problem, which needs more active air quality monitoring and analyses. To assess air quality characteristics over the city of Zahedan, southeast Iran, airborne particulate matter (PM) concentrations with aerodynamic diameters of <10, <2.5, and <1.0 μm were measured during the period July 2008 to March 2010 using an Environmental Dust Monitor (EDM-180). The data were analyzed on a daily, monthly, and seasonal basis. The highest monthly mean PM₁₀ levels (172 μg m^?3) were recorded during the summer period (June–August), presumably due to frequent dust storms from the nearby Sistan desert located to the north, while less PM₁₀ concentrations are recorded in winter (December–February; 101 μg m^?3). Linear regression analysis between the PM_2.5 and PM₁₀ time series reveals high correlation coefficients (r?>?0.82) for all seasons, implying that PM₁₀ and PM_2.5 may have the same source regions or that they are influenced by the same local conditions. In contrast, neutral correlation is found between PM₁₀ and PM_1.0 in autumn and winter. Taking into account that the annual variation of PM_1.0 exhibits a clear pattern of peaking in winter and dropping in summer (in contrast to PM₁₀), it is suspected that PM_1.0 is of different origin than PM₁₀ and mainly influenced by local anthropogenic emissions. The daily PM₁₀ variation is strongly seasonally defined. The maximum PM₁₀ concentrations occur in the morning hours during winter, autumn (September–November), and early spring (March), while in summer, PM₁₀ concentrations increase significantly in the afternoon, closely associated with the intense northerly winds blowing from the desert. As far as the Air Quality Index (AQI) is concerned, its highest monthly values occur in summer, while they are reduced in winter. Desert dust aerosols are found to be the major component in determining the AQI in Zahedan. The analysis shows that 15.3% of the days are unhealthy for sensitive people, while 2% are considered as hazardous.     

Up-regulation of MRP4 and down-regulation of influx transporters in human leukemic cells with acquired resistance to 6-mercaptopurine

To investigate the mechanism of cellular resistance to 6-MP, we established a 6-MP resistant cell line (CEM-MP5) by stepwise selection of the human T-lymphoblastic leukemia cell line (CEM). CEM-MP5 cells were about 100-fold resistant to 6-MP compared with parental CEM cells. Western blot analysis demonstrated that multidrug resistant protein 4 (MRP4) was increased in CEM-MP5 cells, whereas the levels of the nucleoside transporters hENT1, hCNT2 and hCNT3 were decreased compared with those of parental CEM cells. Consistent with the operation of an efflux pump, accumulation of [14C]6-MP and/or its metabolites was reduced, and ATP-dependent efflux was increased in CEM-MP5 cells. Taken together these results showed that up-regulation of MRP4 and down-regulation of influx transporters played a major role in 6-MP resistance of CEM-MP5 cells.     

The multifaceted therapeutic potential of benfotiamine

Thiamine, known as vitamin B₁, plays an essential role in energy metabolism. Benfotiamine (S-benzoylthiamine O-monophoshate) is a synthetic S-acyl derivative of thiamine. Once absorbed, benfotiamine is dephosphorylated by ecto-alkaline phosphatase to lipid-soluble S-benzoylthiamine. Transketolase is an enzyme that directs the precursors of advanced glycation end products (AGEs) to pentose phosphate pathway. Benfotiamine administration increases the levels of intracellular thiamine diphosphate, a cofactor necessary for the activation transketolase, resulting in the reduction of tissue level of AGEs. The elevated level of AGEs has been implicated in the induction and progression of diabetes-associated complications. Chronic hyperglycemia accelerates the reaction between glucose and proteins leading to the formation of AGEs, which form irreversible cross-links with many macromolecules such as collagen. In diabetes, AGEs accumulate in tissues at an accelerated rate. Experimental studies have elucidated that binding of AGEs to their specific receptors (RAGE) activates mainly monocytes and endothelial cells and consequently induces various inflammatory events. Moreover, AGEs exaggerate the status of oxidative stress in diabetes that may additionally contribute to functional changes in vascular tone control observed in diabetes. The anti-AGE property of benfotiamine certainly makes it effective for the treatment of diabetic neuropathy, nephropathy and retinopathy. Interestingly, few recent studies demonstrated additional non-AGE-dependent pharmacological actions of benfotiamine. The present review critically analyzed the multifaceted therapeutic potential of benfotiamine.