Antibacterial activity of silver nanoparticles dispersion against MSSA and MRSA isolated from wounds in a tertiary care hospital of north India.

Staphylococcus aureus, the main cause of nosocomial infection worldwide result in significant increases in mortality, morbidity, and cost related to prolong treatments. Silver compound has been in use since time immemorial for the treatment of burns, wounds and several other bacterial infections. In the present work, we explore the antibacterial activity of silver nanoparticles (Ag-NPs) dispersion (5-10 nm) against reference strain and clinical isolates of Methicillin-sensitive S. aureus (MSSA), and Methicillin-Resistant S. aureus (MRSA).The typical minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against standard reference strain as well as, MSSA and MRSA were observed in the range of 12-48 μg/ml and 12-96 μg/ml, respectively. The MBC/MIC ratios against all strains were found in the range of ≤1 to ≤4, which shows that Ag-NPs inhibit bacterial growth in a bactericidal rather than a bacteriostatic manner. Our finding suggests that Ag-NPs are effective broad-spectrum antibacterial agents regardless of their drug-resistance mechanisms.

Evaluationof ParaSight F Test in Dignosis of Plasmodium Falciparum Infection.

P. falciparum malaria is a severe form of disease which requires urgent diagnosis and treatment to save the life of patient. Blood smear examination is the commonest method used for diagnosis. The present study was done to evaluate ParaSight F test in patients of P. falciparum infection.The study was performed on 100 patients who where clinically diagnosed as cases of P. falciparum infection. ParaSight F test and Leishman stained blood smear examination was done in all 100 patients (50 patients of cerebral malaria + 50 patients of acute malaria).ParaSight F test was positive in 45 patients and blood smear positive in 28 patients of cerebral malaria. 35 patients of acute malaria were positive by ParaSight F test while blood smear was positive in 15 patients. Sensitivity, specificity, positive and negative predictive values of ParaSight F test are 95.7%, 100%, 100%, 100%, 60% in cerebral malaria and 100% each in acute malaria. ParaSight F test can be used as diagnostic tool in cases of P. falciparum infections, where blood smear is negative.

Comparison of different diagnostic techniques in Plasmodium falciparum cerebral malaria.

BACKGROUND & OBJECTIVES: Plasmodium falciparum cerebral malaria remains a major health problem in India. The efficacy of treatment of cerebral malaria lies in its early diagnosis through rapid diagnostic methods. ParaSights-F test detects HRP-2 antigen secreted by parasitised red blood cells and quantitative buffy coat assay (QBC) is examination of buffy coat for the presence of malarial parasite stained with acridine orange. This study was performed to evaluate the effectiveness of ParaSight-F test and QBC assay as diagnostic methods in the patients of cerebral malaria. METHODS: Fifty clinically diagnosed patients of cerebral malaria were included in the study. ParaSight-F test, QBC and conventional blood smear examination was done. Patients who were in coma and there were no obvious features of bacterial or viral etiology were investigated for cerebral malaria by these diagnostic methods. RESULTS: ParaSight-F test, QBC and peripheral blood smears were examined. Patients were followed-up for signs of clinical recovery. ParaSight-F test was positive in 47 patients, QBC in 46 while blood smear examination was positive in 28 cases. INTERPRETATION & CONCLUSION: Sensitivity and specificity of ParaSight-F test were found to be 96.6 and 94% while QBC showed 97.8 and 100% respectively. ParaSight-F test and QBC were found to be novel methods for diagnosis of cerebral malaria especially in the cases where diagnosis can not be made by conventional blood smear examination due to low parasitaemia. These rapid diagnostic methods help in early therapeutic intervention.