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Vellore is endemic for cholera due to Vibrio cholerae O1 and O139. In a previous study the prevalence of Vibrio cholerae in drinking water, lakes and sewage outfalls in a single 2-months period in Vellore, India was determined. In addition water samples from three sites were also tested for the presence of V. cholerae O1 and O139 by fluorescent antibody staining. This follow on study has examined how the environmental distribution of V. cholerae at the same sites alters over a 12-month period and the relationship to the clinical pattern of cholera in Vellore. Samples of water were collected from fixed sites at three water bodies each month between April 1997 and March 1998. Bacteria isolated from samples were identified by standard biochemical tests and isolated strains of V. cholerae tested for their ability to agglutinate O1 and O139 antisera. Samples were also tested for the presence of V. cholerae O1 and O139 by fluorescent antibody staining. The clinical isolation rate of V. cholerae in Vellore, maximum temperature and rainfall were also studied. The results demonstrate the presence in the environment of viable but non-cultivable (VNC) V. cholerae in 10 of 12 months of the study year as well as their viability. Their prevalence in the environment also correlated with the isolation of these pathogens from clinical samples over the same study period.

The prevalence of Vibrio cholerae in drinking water, lakes and sewage outfalls during July and August 1996 in Vellore, India was determined. Drinking water samples were collected on single occasions from 12 sites in different geographic areas of the town where cholera had been reported. Samples of water, plankton and sediment were collected from fixed sites at three lakes on three occasions separated by at least 3 days during the course of the study. Samples from open sewers were taken from two representative sites in four areas of the town. Bacteria isolated from samples were identified by standard biochemical tests and isolated strains of V. cholerae tested for their ability to agglutinate O1 and O139 antisera. Water samples from lakes were also tested for the presence of V. cholerae O1 and O139 by fluorescent antibody staining. Non-O1, non-O139 strains of V. cholerae were detected in 41% of drinking water samples and 100% of water, sediment and plankton samples from the test lakes. Eighty-seven per cent of open sewers sampled contained viable non-O1, non-O139 V. cholerae. Fluorescent antibody staining gave positive results for V. cholerae O1 and O139 for all water samples from the three lake sites. Strains of Aeromonas spp. were isolated from 58% of drinking water samples and from 66% of sediment, 77% of plankton and 55% of water samples from lakes. All open sewers sampled contained Aeromonas spp. PCR amplification employing specific primers demonstrated that none of the non-agglutinating V. cholerae isolates contained the ctx operon. The non-O1, non-O139 V. cholerae isolates showed different patterns of antibiotic resistance to ampicillin, ciprofloxacin, chloramphenicol, tetracycline and trimethoprim.

Abstract: Brief exposure of Beta vulgaris root cultures to acidic medium resulted in release of betalain pigments while the capability for regrowth and continued pigment accumulation was retained. A 10-min exposure to pH 2 followed by return to standard growth medium (pH 5.5, 1.1 mM PO4) resulted in release of 0.59 mg pigment/g dry weight over the subsequent 24-h period. The released pigment corresponds to 36.8% of the total pigments. Further improvement in culture productivity was achieved through phosphate limitation. Specific pigment productivity increased fivefold for cultures grown in phosphate-free medium as compared to cultures grown in control medium (1.1 mM PO4). A maximum total pigment production of 25.2 mg/l was observed at an initial medium phosphate level 0.3 mM. When combined with phosphate limitation, low pH facilitated the release of 3.03 mg pigment/g dry weight, which corresponds to 50% of the total pigment. The permeabilized roots were capable of regrowth and continued pigment accumulation. A cytochemical assay for respiratory activity revealed that the basis of regrowth was lateral root initials that were unaffected during the acidic pH treatment.

This study was conducted in a tertiary care teaching hospital in south India to evaluate the association of drug resistant tuberculosis (TB) in diabetic subjects. There were: 361 subjects with positive mycobacterial culture and susceptibility tests results over a 3-year period; 267 (74%) acid-fast bacillus smear positive; and 94 (26%) smear negative cases. One hundred and seventy-seven (49%) had resistant isolates to any one first line anti TB drugs (resistant group) and 184 (51%) had isolates sensitive to all drugs (non-resistant group). In the resistant and non-resistant subjects the mean duration of TB symptoms was, respectively, 22 months and 4.5 months, past history of TB 126 (71%) and 48 (26%), past anti TB drug therapy 126 (71%) and 47 (25%), inadequate anti TB drug therapy 42 (24%) and 23 (13%), HIV positive six and 13 subjects. There were 72 diabetic subjects [35 and 37, respectively] with a duration of diabetes 5.8 ± 7.5 years and 3.7 ± 5.0 years in the resistant and non-resistant groups. Twenty-six per cent of the diabetic subjects (19/72) had multi-drug resistant TB. Drug resistance to first line anti-TB drugs was not found to be associated with diagnosis or duration of diabetes mellitus.

Tuberculosis and more so the multi drug resistant variety has been thrust into the forefront as a serious and life threatening illness in recent years. The advent of AIDS contributes to this substantially, especially in the developed world where it had become practically non- existent. We reviewed our data over the past 20 years with a view to determine when drug resistance began to manifest in the strains.

Of 213 renal allgroft recipients suspected to have had pulmonary tuberculosis, 132 had sputum examinations and 14 showed acid-fast bacilli. Of the remaining 118 patients, 25 had gastric aspirations, 18 had bronchoalveolar lavage, and 75 did not require further investigation because of spontaneous improvement or confirmation of an alternative diagnosis. While 9 of the 25 patients' gastric aspirate examination was positive, all the 18 who had bronchoalveolar lavage were negative for acid-fast bacilli. Eighty-one patients without expectoration had gastric aspiration directly and 14 showed acid-fast bacilli. Of the remaining 67 patients only 17 had bronchoalveolar lavage, of which three were positive for AFB and the rest did not require further testing for tuberculosis.