Transmission dynamics of methicillin-resistant Staphylococcus aureus in a medical intensive care unit in India

Background

Methicillin-resistant Staphylococcus aureus (MRSA) is a global pathogen and an important but seldom investigated cause of morbidity and mortality in lower and middle-income countries where it can place a major burden on limited resources. Quantifying nosocomial transmission in resource-poor settings is difficult because molecular typing methods are prohibitively expensive. Mechanistic statistical models can overcome this problem with minimal cost. We analyse the transmission dynamics of MRSA in a hospital in south India using one such approach and provide conservative estimates of the organism''s economic burden.

Methods and Findings

Fifty months of MRSA infection data were collected retrospectively from a Medical Intensive Care Unit (MICU) in a tertiary hospital in Vellore, south India. Data were analysed using a previously described structured hidden Markov model.Seventy-two patients developed MRSA infections and, of these, 49 (68%) died in the MICU. We estimated that 4.2% (95%CI 1.0, 19.0) of patients were MRSA-positive when admitted, that there were 0.39 MRSA infections per colonized patient month (0.06, 0.73), and that the ward-level reproduction number for MRSA was 0.42 (0.08, 2.04). Anti-MRSA antibiotic treatment costs alone averaged $124/patient, over three times the monthly income of more than 40% of the Indian population.

Conclusions

Our analysis of routine data provides the first estimate of the nosocomial transmission potential of MRSA in India. The high levels of transmission estimated underline the need for cost-effective interventions to reduce MRSA transmission in hospital settings in low and middle income countries.     

Nephroprotective effect of pigmented violacein isolated from Chromobacterium violaceum in wistar rats

The present study aimed to analyze the nephroprotective property of violacein obtained from the bacterium, Chromobacterium violaceum. The nephrotoxicity in the animal model was induced by gentamicin, potassium dichromate, mercuric chloride, and cadmium chloride-induced nephrotoxicity in the Wistar rats was analyzed by measuring the serum creatinine, uric acid, and urea level. The present investigation revealed the nephroprotective property on convoluted proximal tubule (S1 and S2 segments) and the straight proximal tubule (S3 segment). Also, violacein significantly improved the renal function by the renal protective property on S2 segment of proximal tubule from the nephrotoxicity stimulated by mercuric chloride, potassium dichromate, cadmium chloride and gentamicin in animal models. Animal model studies revealed that violacein at 20 and 40 mg/kg p.o improved the renal function and significantly reduced the increased amount of uric acid, creatinine, and blood urea compared to the control.     

Absence of birth-weight lowering effect of ADCY5 and near CCNL, but association of impaired glucose-insulin homeostasis with ADCY5 in Asian Indians

Background

A feature of the Asian Indian phenotype is low birth weight with increased adult type 2 diabetes risk. Most populations show consistent associations between low birth weight and adult type 2 diabetes. Recently, two birth weight-lowering loci on chromosome 3 (near CCNL1 and ADCY5) were identified in a genome-wide association study, the latter of which is also a type 2 diabetes locus. We therefore tested the impact of these genetic variants on birth weight and adult glucose/insulin homeostasis in a large Indian birth cohort.

Methodology/Principal Findings

Adults (n = 2,151) enrolled in a birth cohort (established 1969-73) were genotyped for rs900400 (near CCNL1) and rs9883204 (ADCY5). Associations were tested for birth weight, anthropometry from infancy to adulthood, and type 2 diabetes related glycemic traits. The average birth weight in this population was 2.79±0.47 kg and was not associated with genetic variation in CCNL1 (p = 0.87) or ADCY5 (p = 0.54). Allele frequencies for the ‘birth weight-lowering’ variants were similar compared with Western populations. There were no significant associations with growth or adult weight. However, the ‘birth weight-lowering’ variant of ADCY5 was associated with modest increase in fasting glucose (β 0.041, p = 0.027), 2-hours glucose (β 0.127, p = 0.019), and reduced insulinogenic index (β -0.106, p = 0.050) and 2-hour insulin (β -0.058, p = 0.010).

Conclusions

The low birth weight in Asian Indians is not even partly explained by genetic variants near CCNL1 and ADCY5 which implies that non-genetic factors may predominate. However, the ‘birth-weight-lowering’ variant of ADCY5 was associated with elevated glucose and decreased insulin response in early adulthood which argues for a common genetic cause of low birth weight and risk of type 2 diabetes.     

Associations of Variants in FTO and Near MC4R With Obesity Traits in South Asian Indians

Recent genome‐wide association studies show that loci in FTO and melanocortin 4 receptor (MC4R) associate with obesity‐related traits. Outside Western populations the associations between these variants have not always been consistent and in Indians it has been suggested that FTO relates to diabetes without an obvious intermediary obesity phenotype. We investigated the association between genetic variants in FTO (rs9939609) and near MC4R (rs17782313) with obesity‐ and type 2 diabetes (T2DM)‐related traits in a longitudinal birth cohort of 2,151 healthy individuals from the Vellore birth cohort in South India. The FTO locus displayed significant associations with several conventional obesity‐related anthropometric traits. The per allele increase is about 1% for BMI, waist circumference (WC), hip circumference (HC), and waist—hip ratio. Consistent associations were observed for adipose tissue‐specific measurements such as skinfold thickness reinforcing the association with obesity‐related traits. Obesity associations for the MC4R locus were weak or nonsignificant but a signal for height (P < 0.001) was observed. The effect on obesity‐related traits for FTO was seen in adulthood, but not at younger ages. The loci also showed nominal associations with increased blood glucose but these associations were lost on BMI adjustment. The effect of FTO on obesity‐related traits was driven by an urban environmental influence. We conclude that rs9939609 variant in the FTO locus is associated with measures of adiposity and metabolic consequences in South Indians with an enhanced effect associated with urban living. The detection of these associations in Indians is challenging because conventional anthropometric obesity measures work poorly in the Indian “thin‐fat” phenotype.     

Pattern of menstrual cycle length in south Indian women: a prospective study.

Data on 8,308 menstrual cycles from 1,740 South Indian women prospectively recorded were analyzed to identify the effect of age on menstrual cycle length. The distribution was skewed to the right with the mean (SD) cycle length of 31.8 (6.7) days. The range of 25-40 days constituted 10-82 per cent of menstrual cycle lengths. In no age group did 28-day cycles occur in more than 9 per cent of women. Variability as measured by the standard deviation was high among those below 19 years of age, stabilized during 25-39 years, and then increased in women aged 40 years or more. The findings are discussed in the light of other studies and possible implications in fertility control programs.     

Regeneration of Indian ginseng plantlets from stem callus

The development of stem callus mediated plant regeneration system for Withania somnifera is described. Maximum callus proliferation was obtained on Murashige and Skoog medium supplemented with 2.26 μM 2,4-D. Three-week-old, white, friable callus was used for shoot regeneration. The maximum shoot regeneration (6.2 ± 0.34 shoots/explant) was achieved in four weeks when callus was cultured on MS medium fortified with 4.44 μM BA and 0.57 μM IAA. Regenerated shoots were excised and multiplied (8.4 ± 0.43 shoots/explant) on MS medium supplemented with 4.44 μM of BA. Multiple shoots were divided into single shoots and were rooted (5.1 ± 0.49 rootlets/shoot) on half strength MS medium supplemented with 9.84 μM of IBA. After a hardening phase of 3 weeks the plantlets were transferred to the field. This revised version was published online in June 2006 with corrections to the Cover Date.     

Anti-inflammatory activity of rhein isolated from the flowers of Cassia fistula L. and possible underlying mechanisms

Objective

Anti-inflammatory activity of rhein in animal models with potential mechanism of actions.