Triclosan in water, implications for human and environmental health.

Triclosan (TCS) is a broad spectrum antibacterial agent present as an active ingredient in some personal care products such as soaps, toothpastes and sterilizers. It is an endocrine disrupting compound and its increasing presence in water resources as well as in biosolid-amended soils used in farming, its potential for bioaccumulation in fatty tissues and toxicity in aquatic organisms are a cause for concern to human and environmental health. TCS has also been detected in blood, breast milk, urine and nails of humans. The significance of this is not precisely understood. Data on its bioaccumulation in humans are also lacking. Cell based studies however showed that TCS is a pro-oxidant and may be cytotoxic via a number of mechanisms. Uncoupling of oxidative phosphorylation appears to be prevailing as a toxicity mechanism though the compound's role in apoptosis has been cited. TCS is not known to be carcinogenic per se in vitro but has been reported to promote tumourigenesis in the presence of a carcinogen, in mice. Recent laboratory reports appear to support the view that TCS oestrogenicity as well as its anti-oestrogenicity play significant role in cancer progression. Results from epidemiological studies on the effect of TCS on human health have implicated the compound as responsible for certain allergies and reproductive defects. Its presence in chlorinated water also raises toxicity concern for humans as carcinogenic metabolites such as chlorophenols may be generated in the presence of the residual chlorine. In this paper, we carried out a detailed overview of TCS pollution and the implications for human and environmental health.

Helicobacter pylori prevalence in dyspeptic patients in the Eastern Cape province - race and disease status.

Objectives. We examined Helicobacter pylori infection in patients with gastric-related morbidities at Livingstone Hospital, Port Elizabeth, to determine the prevalence and risk factors for infection according to race, endoscopic diagnosis, age and sex. Methods. Gastric biopsies were collected from 254 consecutive patients and H. pylori isolated on Columbia agar base supplemented with 7% sheep's blood and Skirrow's supplement containing trimethoprim (2.5 mg), vancomycin (5 mg) and cefsulodin (2.5 mg). Amphotericin (2.5 mg) was added to the medium. Recovered isolates were identified following standard microbiology and biochemical techniques. Presumptive isolates were further confirmed by polymerase chain reaction (PCR) targeting the glmM gene. Fisher's exact test was used to assess the univariate association between H. pylori infection and the possible risk factors. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were calculated to measure the strength of association, using EPI INFO 3.41 software. P-values <0.05 were required for significance. Results. The overall prevalence of H. pylori was 66.1% (168/254). Of the 168 positive subjects, H. pylori prevalence was highest in patients with non-ulcer dyspepsia (NUD) (32.7%; 55/168), and lowest (0%; 0/168) in those with atypical oesophageal reflux disease and gastroduodenitis, respectively. The prevalence of infection was highest among coloureds (68.4%; 89/130) and lowest in whites (59.5%; 25/ 42). Prevalence increased with age. Conclusion. The prevalence of H. pylori is high in dyspeptic patients in Eastern Cape Province. Gender, antibiotic treatment and alcohol consumption may be risk factors for infection. These findings are of clinical and epidemiological significance.

Helicobacter pylori antigenemia in an asymptomatic population of Eastern Cape Province, South Africa: public health implications.

Helicobacter pylori is a major cause of such upper gastrointestinal diseases as gastritis, peptic ulcer, and gastric cancer. The risk of infection is increased in those living in the developing world, which has been ascribed to precarious hygiene standards, crowded households, and deficient sanitation common in this part of the world. Fecal samples were collected from 356 apparently healthy subjects, consisting of 168 males and 188 females aged from 3 months to > or = 60 years (Mean = 31 years). A standardized questionnaire describing demographic characteristic including age, sex, household hygiene, socioeconomic status, and so on was applied. A sandwich-type enzyme immunoassay amplification technology (Amplified IDEIA Hp StAR, Oxoid, UK) was used to analyze the fecal samples for the detection of H. pylori antigens using monoclonal antibodies specific for H. pylori antigens. Fisher's exact test was used to assess the univariate association between H. pylori infection and the possible risk factors. Odds ratio (OR) and the corresponding 95% confidence interval (CI) were calculated to measure the strength of association using EPI INFO 3.41 package. P values of < .05 were required for significance. H. pylori antigen was detected in 309 of the 356 subjects giving an overall prevalence of 86.8%. Prevalence increased with age from 75.9% in children < 12 years age to 100% in young adults aged 25-47 years and subjects aged > or = 60 years (P < .05). H. pylori prevalence was higher in females than in males. Of 188 females who participated in the study, H. pylori antigen was detected in 172 (91.5%) versus 144 (85.7%) 168 males (P > .05). Interestingly, H. pylori antigen was detected more often (100%) in the high socioeconomic group than in those of low socioeconomic group (85.9%) (P > .05). The results of this study have revealed a high prevalence of H. pylori antigens in fecal samples of asymptomatic individuals in the Nkonkobe municipality, an indication of active infection. Socioeconomic status, contaminated water, and poor sanitation may play a role in H. pylori transmission in this population. This finding is of public health and epidemiologic significance.

An African perspective on Helicobacter pylori: prevalence of human infection, drug resistance, and alternative approaches to treatment.

Helicobacter pylori is a Gram-negative, micro-aerophilic, motile, curved rod that inhabits the gastric mucosa of the human stomach. It chronically infects thousands of millions of people world-wide, and is one of the most genetically diverse of bacterial species. Infection with the bacterium leads to chronic gastritis, peptic ulceration, gastric cancers and gastric mucosa-associated lymphoid-tissue (MALT) lymphoma. The prevalence of infection appears to be partly determined by geographical and socio-demographic factors, being higher in Africa than elsewhere. Current treatment, based on potent combinations that each consist of a proton-pump inhibitor and two antibiotics, is successful in 80%-90% of patients. Some undesirable side-effects, poor patient compliance and drug resistance are, however, associated with significant levels of treatment failure and with contra-indications for some patients. Antibiotic resistance in H. pylori is a growing global concern that merits the urgent attention of public-health authorities. Numerous pieces of clinical evidence have revealed that eradication of the organism from a patient results in improvement of gastritis and drastically decreases the frequency of relapse of gastric and duodenal ulcers. Natural products, including medicinal plants and honey, may offer useful alternatives in the treatment of H. pylori-related infections.

The isolation and partial characterization of precursor forms of ostrich carboxypeptidase.

Ostrich carboxypeptidases A and B were recently purified and characterized. The aim of this study was to isolate and purify, and partially characterize in terms of molecular weight, pI, amino acid composition and N-terminal sequencing, the precursor forms of carboxypeptidases from the ostrich pancreas. Inhibition studies with soybean trypsin inhibitor and activation studies with three proteases (bovine trypsin, bovine chymotrypsin and porcine elastase) were performed on crude ostrich acetone powder and the carboxypeptidase A and B activities were determined. SDS-PAGE was carried out after every incubation to monitor the rate and degree of conversion of a M(r) 66K component to procarboxypeptidase and carboxypeptidase A and B. The precursor forms were purified by Toyopearl Super Q and Pharmacia Mono Q chromatography. All three proteases converted the M(r) 66K component to procarboxypeptidases and carboxypeptidases over a set time interval, with carboxypeptidase A and B activities being detected in the acetone powder. Chymotrypsin was the preferred protease since it exhibited a more controlled activation of the procarboxypeptidases. The amino acid composition of procarboxypeptidase A revealed 525 residues. The N-terminal sequence of procarboxypeptidase A showed considerable homology when compared with several other mammalian sequences. M(r) and pI values of 52K and 5.23 were obtained for procarboxypeptidase A, respectively. This study indicated that ostrich procarboxypeptidase A is closely related to other mammalian procarboxypeptidase A molecules in terms of physicochemical properties.