Bacteriological quality of bottled drinking water versus municipal tap water in Dharan municipality, Nepal

Background: Water-related diseases are of great concern in developing countries like Nepal. Every year, there are countless morbidity and mortality due to the consumption of unsafe drinking water. Recently, there have been increased uses of bottled drinking water in an assumption that the bottled water is safer than the tap water and its use will help to protect from water-related diseases. So, the main objective of this study was to analyze the bacteriological quality of bottled drinking water and that of municipal tap water. Methods: A total of 100 samples (76 tap water and 24 bottled water) were analyzed for bacteriological quality and pH. The methods used were spread plate method for total plate count (TPC) and membrane filter method for total coliform count (TCC), fecal coliform count (FCC), and fecal streptococcal count (FSC). pH meter was used for measuring pH. Results: One hundred percent of the tap water samples and 87.5 % of the bottled water samples were found to be contaminated with heterotrophic bacteria. Of the tap water samples, 55.3 % were positive for total coliforms, compared with 25 % of the bottled water. No bottled water samples were positive for fecal coliforms and fecal streptococci, in contrast to 21.1 % and 14.5 % of the tap water samples being contaminated with fecal coliforms and fecal streptococci, respectively. One hundred percent of the tap water samples and 54.2 % of the bottled water samples had pH in the acceptable range. Conclusions: All of the municipal tap water samples and most of the bottled drinking water samples distributed in Dharan municipality were found to be contaminated with one or more than one type of indicator organisms. On the basis of our findings, we may conclude that comparatively, the bottled drinking water may have been safer (than tap water) to drink

Antimicrobial Susceptibility Patterns of Salmonella enterica Serotype Typhi in Eastern Nepal

The aim of the present study was to evaluate antimicrobial susceptibility patterns with special reference to multidrug resistance, susceptibility to ciprofloxacin, and bacteriophage typing of Salmonella enterica serotype Typhi isolated from blood sent for culture in a tertiary-care teaching hospital in eastern Nepal during January 2000\u2013December 2004. In total, 132 strains of S. enterica Typhi, isolated from 2,568 blood culture samples collected from cases of suspected enteric fever, were tested for susceptibility to commonly-used antimicrobials by the disc-diffusion method. There were 35 multidrug-resistant strains. None of the isolates were resistant to ciprofloxacin.Of 52 isolates tested for minimum inhibitory concentration (MIC) of ciprofloxacin, 36 (69.23%) showed reduced susceptibility (MIC 650.25 mg/L). Of 112 strains tested for nalidixicacid susceptibility,86(76%) were resistant. Strains with reduced susceptibility to ciprofloxacin and resistance to nalidixic acid could be correlated. The commonest phage type was E1. Nalidixic acid susceptibility could be a useful screening test for the detection of decreased susceptibility of S. Typhi to ciprofloxacin, a drug which is commonly used even for minor ailments in this area

Demographic and clinico-pathological profile of carcinoma stomach in a tertiary referral centre of Eastern India

Objectives: This prospective study was done to assess the incidence, clinical presentations, histopathological subtypes of gastric adenocarcinoma in a referral institute of Eastern India. Methods: The patients admitted with diagnosis of gastric carcinoma in a tertiary referral hospital in Eastern India between January2006 to December2010 were included in this study. Data were compiled and analyzed with regards to their age, sex, socioeconomic status, their clinical presentations, site of lesion & histopathological subtypes. Results: 150 patients were included in this study of which 50 patients were of ≤50 years age. The median age group was 57 years. The male: female ratio was 2.3:1. Most of the patients were from lower socioeconomic strata (55.33%). Anemia (41.33%) and weight loss (38%) were the predominant presenting features irrespective of age, whereas gastric outlet obstruction due to antral growths was the commonest presentation in patients of ≤50 years age group. The most common histopathological type was adenocarcinoma; patients of≤50 years of age group presented with well differentiated and moderately differentiated adenocarcinoma while those in >50 years age group with poorly differentiated growth. Most (82.66%) of the patients presented with advanced growth(T3/T4). Conclusion: 1) The incidence of gastric carcinoma in patients younger than 50 years was more common than Western world. 2) Patients are presenting more with lesion in distal stomach than Western world. 3) Gastric outlet obstruction and metastatic disease are commoner than abdominal lump and upper GI bleeding. The latter being the commoner presentations in Western world. 4) Regarding the histological type, adenocarcinoma are commoner than in Western world and 5) Patients with signet cell subtype are much less than Western world

Evaluation of nitrate reductase assay in 7H11 agar for diagnosis of multi-drug-resistant tuberculosis in eastern Nepal

Abstract Background Emergence of multi-drug-resistant tuberculosis is a serious challenge for successful global tuberculosis control. Early diagnosis of drug-resistant tuberculosis by direct nitrate reductase assay (NRA) aids in appropriate treatment and reduction in disease transmission, particularly in countries with high tuberculosis burden. The aim of this study was to evaluate the performance of NRA for direct detection of resistance to rifampicin and isoniazid in Mycobacterium tuberculosis in laboratories with limited resources. Methods Fifty-eight new smear-positive sputum samples were processed as per the guidelines of revised national tuberculosis control program, India. The performance of NRA on middlebrook 7H11 agar was evaluated for detection of rifampicin and isoniazid resistance directly on smear-positive sputum specimens, and the results were compared with conventional proportion method. Sensitivity and specificity of the test were compared with the gold standard proportion method. Mc Nemar chi-square test was used to find out the significant difference between two methods. Results Direct NRA for detection of rifampicin resistance was 85.7% sensitive and 100% specific, whereas sensitivity and specificity of isoniazid resistance were 87.5% and 100%, respectively. Agreement between NRA and proportion method was 98% for both the drugs. The mean days of drug susceptibility testing results were 19.3 days for NRA and 72 days for conventional proportion method. The results of NRA were available in 21 days for 83% of the samples. Conclusions Direct NRA on middlebrook 7H11 medium is a highly sensitive, reliable, and significantly faster method to perform drug susceptibility testing. It has the potential to be implemented for rapid detection of multi-drug-resistant tuberculosis against insufficient resources

Anomalous enhancement in the magnetoconductance of graphene/CoFe₂O₄ composite due to spin–orbit coupling

To understand the effect of charge transfer from the d-orbital of transition metal (TM) to the graphene p-orbital at the graphene/TM interface, magnetoconductance measurements have been carried out in graphene/CoFe₂O₄ composites over the temperature range from 20–300 K. A transition from positive to negative magnetoconductance is observed at 80 K. Below 80 K, magnetoconductance increases with decreasing temperature in the usual way; however, above 80 K it increases unusually with increasing temperature and reaches about 65% at 300 K. This anomalous enhancement in magnetoconductance at the higher temperature region has been explained on the basis of spin–orbit coupling acting at the interface. The nanocomposite containing large interfaces between graphene and CoFe₂O₄ nanoparticles exhibits a superior magnetodielectric effect with a 22% change in dielectric permittivity for an applied magnetic field of 1.8 T as a result of the combined effect between the Maxwell–Wagner polarization at the interface and a positive magnetoconductance of CoFe₂O<sub>4.</sub

Role Reversals in a Tri-Trophic Prey–Predator Interaction System: A Model-Based Study Using Deterministic and Stochastic Approaches

It is frequently observed that adult members of prey species sometimes use their predation mechanism on juvenile members of predator species. Ecological literature describes this phenomenon as prey–predator role reversal dynamics.Numerous authors have observed and described the biological development behind this feeding behaviour. However, the dynamics of this role reversal have hardly been illustrated in the literature in a precise way. In this regard, we formulated an ecological model using the standard prey–predator interactions, allowing for a reverse feeding mechanism. The mathematical model consisted of a three-species food-web structure comprising the common prey, intermediate predator, and top predator. Note that a role-reversal mechanism was observed between the intermediate and top predators based on the scarcity of the prey population. However, we observed the most critical parameters had a significant effect on this reverse feeding behaviour. The bifurcation analysis is the primary criterion for this identification. The proposed deterministic model is then extended to its stochastic analogue by allowing for environmental influences on the tri-trophic food web structure. The conditional moment approach is applied to obtain the equilibrium distribution of populations and their conditional moments in the system. The stochastic setup analysis also supports the stability of this food chain structure, with some restricted conditions. Finally, to facilitate the interpretation of our mathematical results, we investigated it using numerical simulations

Antimicrobial Susceptibility Patterns of Salmonella enterica Serotype Typhi in Eastern Nepal

The aim of the present study was to evaluate antimicrobial susceptibility patterns with special reference to multidrug resistance, susceptibility to ciprofloxacin, and bacteriophage typing of Salmonella enterica serotype Typhi isolated from blood sent for culture in a tertiary-care teaching hospital in eastern Nepal during January 2000–December 2004. In total, 132 strains of S. enterica Typhi, isolated from 2,568 blood culture samples collected from cases of suspected enteric fever, were tested for susceptibility to commonly-used antimicrobials by the disc-diffusion method. There were 35 multidrug-resistant strains. None of the isolates were resistant to ciprofloxacin.Of 52 isolates tested for minimum inhibitory concentration (MIC) of ciprofloxacin, 36 (69.23%) showed reduced susceptibility (MIC ≥0.25 mg/L). Of 112 strains tested for nalidixicacid susceptibility,86(76%) were resistant. Strains with reduced susceptibility to ciprofloxacin and resistance to nalidixic acid could be correlated. The commonest phage type was E1. Nalidixic acid susceptibility could be a useful screening test for the detection of decreased susceptibility of S. Typhi to ciprofloxacin, a drug which is commonly used even for minor ailments in this area