DNA interactions and promotion in antibacterial activities of ciprofloxacin drug due to formation of mixed-ligand complexes of oxovanadium(IV).

Mixed-ligand complexes of oxovanadium(IV) of the type [VOAL]*2H(2)O [where A = ciprofloxacin and L = uninegative bidentate ligands] have been synthesized and characterized using infrared spectra, electronic spectra, magnetic measurements, elemental analyses, thermal investigation, and mass spectroscopy. Here, we tried to increase an antibacterial activity of ciprofloxacin drug due to formation of mixed-ligand complexes. The complexes were found to be more potent compare to some standard drugs, ligands and metal salt against selective gram(+ve) and gram(-ve) organisms. Binding of the complexes with DNA have been investigated by spectroscopic absorption titration and viscometric techniques. The mixed-ligand complexes show good binding ability. The cleavage efficacy has been determined using gel electrophoresis method and complexes were found to be more active compared to parental ligands and metal salt.

Standardization of a dot blot immunoassay for antigen detection in cases of pulmonary tuberculosis & its evaluation with respect to the conventional techniques.

A simple dot (blot) ELISA test for detecting tubercular antigen in sputum samples of patients of pulmonary tuberculosis has been standardized using nitrocellulose paper. The sensitivity of the assay is 20 ng/ml. The cut-off value was 80 ng/ml. Of the 1042 patients in the study group, the percentage positivity by smear and culture was 54.51 and 57.93 per cent respectively; 68.7 per cent of the ELISA positives were confirmed by smear. The dot blot ELISA could be used as a rapid and specific test as it not only picked up 88.88 per cent of the smear positive, culture positive cases but also 81.89 per cent of the smear negative, culture positive cases. If the results of smear and dot blot ELISA are combined, 91.08 per cent of the culture positive cases were picked up as positive. If such a noninvasive test is commercialized and used in conjunction with smear, the pick up rate of tuberculosis cases will improve considerably.

Evaluation of the recombinant 38-kilodalton antigen of Mycobacterium tuberculosis as a potential immunodiagnostic reagent.

The diagnosis of infection caused by Mycobacterium tuberculosis is of increased public health concern following increases in the number of cases in developed countries and major increases in developing countries associated with the spread of human immunodeficiency virus (HIV) infection. The specificity of purified protein derivative skin testing for the detection of infection is compromised by exposure to environmental mycobacteria. Examination of sputum detects the most infectious patients, but not those with extrapulmonary disease. The 38-kDa antigen of M. tuberculosis contains two M. tuberculosis-specific B-cell epitopes. We overexpressed the gene for this antigen in Escherichia coli and evaluated the recombinant product in in vitro assays of T-cell function and as a target for the antibody response in humans. The sensitivity and specificity of the antigen as a skin test reagent were also assessed in outbred guinea pigs. We found that 69% of healthy sensitized humans recognize the antigen in vitro, as manifested by both cell proliferation and the production of gamma interferon. Untreated patients initially have a lower frequency of response (38%); this recovers to 72% during therapy. A total of 292 patients (20 with HIV coinfection) and 58 controls were examined for production of antibody to the 38-kDa antigen by using a commercially available kit. The sensitivity of the test in comparison with that of culture was 72.6%, and the specificity was 94.9%. The antigen was also tested for its ability to induce skin reactions in outbred guinea pigs sensitized by various mycobacterial species. The antigen provoked significant skin reactions in M. tuberculosis-, M. bovis BCG-, and M. intracellulare-sensitized animals. The significance of these findings and the usefulness of this antigen in immunodiagnosis are discussed.

Role of metronidazole in improving response and specific drug sensitivity in advanced pulmonary tuberculosis.

One hundred and thirty-seven patients of advanced pulmonary tuberculosis were randomly allocated to receive metronidazole 400mg tid (76) or placebo (61) for 2 months in a single blind study. All received streptomycin 0.75 g,INH 30 mg and rifampicin 450 mg daily as standard antitubercle treatment. There were no significant pretreatment differences, among both groups. Compared to placebo group there was superior clinical improvement in metronidazole treated group at 4 and 8 weeks (81% vs 53%-P less than 0.05; 87% vs 72%-P less than 0.05 respectively), greater sputum reduction at 4 weeks (49% vs 9%-P less than 0.001) greater radiologic improvement at 4 weeks (60% vs 43%-P less than 0.01) and a better antituberculous drug sensitivity. Metronidazole seems to have beneficial adjuvant role in the drug treatment of tuberculosis. This may improve response in advanced cases.