Molecular analysis of Salmonella isolates from poultry by pulsed-field gel electrophoresis

Objective: The study was conducted to determine geneticrelatedness of Salmonella serotypes by pulsed field gel electrophoresis (PFGE). Design and Methodology: A total of 1503 caecal samples of freshly slaughtered poultry were randomly collected from 'pluck shops' across the country. The samples were screened for Salmonella by biochemical, serological and molecular methods. The Salmonella serotypes were analyzed for genetic relatedness for phenotypic antimicrobial resistance, resistance and virulence gene profiles by PFGE generated by digestion with XbaI. Results: Ten different serotypes were detected from all 91 Salmonella isolates. PFGE fingerprinting profiles showed that the Salmonella serotypes in general, were genetically diverse with the detection of a total of 20 PFGE groups. The antibiograms of the isolates were also clearly very variable, which suggest that genotypic antimicrobial resistance may not relate to the phenotypic antibiograms in dendrograms, except for qnrB gene. Results demonstrated a varied spectrum of antimicrobial resistance and PFGE patterns among Salmonella isolates and signify the importance of sustained surveillance of foodborne pathogens in retail poultry pluck shops. Conclusions: The findings provide evidence that poultry from pluck shops are colonized by pathogenic Salmonella harboring antimicrobial resistance genes. The study also reported for the first time in Trinidad, molecular characterization of Salmonella isolates from poultry regarding the relatedness of antibiograms, possession of resistance and virulence genes using their PFGE profiles. The epidemiological surveillance of these serotypes would be necessary to evaluate their possible impact on human health in the country and possibly in the Caribbean region.

A strategy for genetic improvement of Barbados Blackbelly sheep in the Caribbean in the context of small flock sizes.

This paper points out that several breeds of prolific sheep in the world possess a major gene for prolificacy. However, the existence of such a major gene in the prolific breeds of hair sheep in the Caribbean remains to be researched. This paper assumes that this gene (F) exists in the Barbados Blackbelly sheep and goes on to outline a strategy to exploit it for the benefit of the small farmer as well as the large private producer. The strategy aims at developing one type of sheep for the small farmer by selective reduction in the frequency of the F gene thereby reducing the frequency of multiple births. The development of another type of highly prolific sheep is suggested for use by the large producer through selective increase in the frequency of the F gene. Large producer is expected to employ high levels of feeding and management including artificial rearing of lambs so as to minimise mortality of multiplets. The paper further discusses within breed selection for genetic improvement in general fitness of hair sheep. In this connection, the development of an open nucleus flock is suggested involving cooperation among participant smallholders.

A strategy for genetic improvement of Barbados Blackbelly sheep in the Caribbean in the context of small flock sizes.

This paper points out that several breeds of prolific sheep in the world possess a major gene for prolificacy. However, the existence of such a major gene in the prolific breeds of hair sheep in the Caribbean remains to be researched. This paper assumes that this gene (F) exists in the Barbados Blackbelly sheep and goes on to outline a strategy to exploit it for the benefit of the small farmer as well as the large private producer. The strategy aims at developing one type of sheep for the small farmer by selective reduction in the frequency of the F gene thereby reducing the frequency of multiple births. The development of another type of highly prolific sheep is suggested for use by the large producer through selective increase in the frequency of the F gene. Large producer is expected to employ high levels of feeding and management including artificial rearing of lambs so as to minimise mortality of multiplets. The paper further discusses within breed selection for genetic improvement in general fitness of hair sheep. In this connection, the development of an open nucleus flock is suggested involving cooperation among participant smallholders.

Evaluation of the CD14/-260 polymorphism and house dust entotoxin exposure in the Barbados Asthma Genetics Study

BACKGROUND: Both a functional promoter polymorphism in the gene encoding CD14 (C-260T) and exposure to endotoxin are believed to play key roles in modulating the immune response and expression of atopic disease. OBJECTIVE: We aimed to evaluate the role of the CD14 C-260T polymorphism in a population of African descent and to test for interaction between this genotype and house dust endotoxin (HDE) exposure on atopic phenotypes. METHODS: Asthmatic probands and their families were recruited as part of the Barbados Asthma Genetics Study. The C-260T polymorphism and two additional CD14 promoter markers (G-1461T, C-1721T) were genotyped. Endotoxin was measured in house dust samples. RESULTS: Using a Family-Based Association Test, the C-260T allele appeared to be protective against asthma (z=−2.444; P=.015) and asthma severity (z=−2.615; P=.009) under a recessive model. No significant associations were observed for the G-1461T and C-1721T markers both individually and in haplotypes. In a case-control analysis, the CD14 TT genotype was found to reduce risk of asthma compared with the CD14 CC/CT genotypes (odds ratio [OR], 0.26; 95% CI, 0.14-0.49) and was associated with lower asthma severity scores (P < .002). The TT genotype might protect against asthma for individuals with low HDE (OR, 0.09; 95% CI, 0.03-0.24), but may be a risk factor for individuals with high HDE (OR, 11.66; 95% CI, 1.03-131.7), suggesting a gene-environment interaction. CONCLUSION: These data suggest that the CD14-260 polymorphism may play a role in controlling risk to atopic disease and underscore the importance of incorporating key environmental exposures into studies of genetic risk factors.

Diabetic nephropathy is not preventable - abstract

Renal failure in diabeties mellitus is becoming the commonest cause of end-stage renal disease (ERSD) in developed and developing countries. While ERSD occurs in about 35 percent of patients with insulin-dependent diabetes mellitus (IDDM), it occurs generally in about 15-60 percent with non-insulin-dependent diabetes mellitus (NIDDM), depending on ethnicity. Since most of the diabetes are NIDDM, it follows that most of these patients developing renal failure and requiring dialysis are NIDDM. When significant proteinuria begins, usually after about 15-20 years of NIDDM or IDDM, renal function will fall steadily and the patient will require dialysis in 3-5 years or sooner. The proteinuric patients also have a 20-40-fold increase in cardiovascular mortality. About one-quarter of the patients who have negative routine urinary protein dipstick tests will have sub-clinical amounts of urinary albumin (30-300 mg/24 hr), so-called microalbuminuria (MA). This has recently been correlated with a very high incidence of microvascular disease. This MA predicts about a 20-fold chance of the patient developing clinical proteinuria and a high chance of ERSD. The accumulated evidence suggests that a common pathogenic mechanism may exist for microalbuminuria, diabetic nephropathy, atherosclerosis and obesity. Obesity seems to be related to all of these factors in that it has been associated with insulin resistance, hypertension and so dium retention, atherosclerosis and hyperlipidaemia (HL). NIDDM patients are almost always obese and they always have insulin resistance, which improves with weight loss. There is growing clinical evidence of hereditary influence in NIDDM, HL, and hypertension with the clustering of diabetic nephropathy in these high-risk families. These data show that genetic factors may well play a major role, and it is therefore understandable that we may have difficulty in altering the already genetically charted course of proteinuria, hypertension, HL, and NIDDM (AU)

Diabetes mellitus and risk factors in a French West Indian island - abstract

Diabetes mellitus is an important cause of morbidity and mortality in the Caribbean. In order to design and implement specific prevention programmes, it is necessary to estimate the prevalence of glycaemic disorders and study the risk factors involved. This paper presents the results of such a study from a representative sample of the adult population in Guadeloupe. The estimated total prevalence of glycaemic disorders was 13.2 per cent of the adult population over 18 years of age. Impaired glucose tolerance (IGT) appeared in 7.4 per cent of subjects. The prevalence of diabetes mellitus was 5.8 per cent (95 per cent confidence interval: 4.4-7.2). Insulin-dependent patients represent 14 per cent of all diabetics. The associated factors studied were sex, age, obesity, parental diabetes status and ethnicity. The relative risk (RR) for age in non-obese non-diabetic parent patients was 5.1. In older subjects, RR for diabetic parent without obesity was 3.2 and for obesity alone 1.8. For obesity and diabetic parent, RR was 5.0. In this case, there was additivity of these two factors. Except age, the individual predominant factor of Diabetes mellitus was the presence of a diabetic parent; this was more evident in the small and closed Indian group. In the Public Health approach, i.e. taking into account the prevalence of each risk factor in the population, obesity was the most important. It is also the one and only factor which could be reached directly by a prevention programme (AU)

Genetic factors in the susceptibility of biomphalaria glabrata for different strains of schistosoma mansoni

Biomphalaria glabrata selected for genetic differences in susceptibility to infection with a Puerto Rican strain of schistosoma mansoni were exposed to a miracidia of a strain of S. mansoni from St. Lucia. The St. Lucian strain was less effective than the Puerto Rican. Results suggested that in snails susceptibility to the St. Lucian strain were determined by a single gene, with insusceptibility dominant (AU)