DNA binding of polycyclic aromatic hydrocarbons in a human bronchial epithelial cell line treated with diesel and gasoline particulate extracts and benzo[a]pyrene.

Particulate matter of vehicle exhaust is known to contain carcinogenic compounds such as polycyclic aromatic hydrocarbons (PAH) and is suggested to increase lung cancer risk in humans. This study examines the differences in diesel and gasoline-derived PAH binding to DNA in a human bronchial epithelial cell line (BEAS-2B). Particulate matter (PM) of gasoline exhaust was collected from passenger cars on filters and semi-volatile compounds on polyurethane foam (PUF).

Comparison of mutagenicity and calf thymus DNA adducts formed by the particulate and semivolatile fractions of vehicle exhausts.

In this study we compared the ability of extractable organic material from particulate and semivolatile fractions of gasoline emission to induce mutations in bacteria and form adducts with calf thymus (CT) DNA with corresponding data obtained from diesel exhaust. Exhaust particles from gasoline-powered passenger cars were collected on filters and semivolatile compounds were collected on polyurethane foam (PUF). The mutagenicity of the soluble organic fraction (SOF) was determined in Salmonella typhimurium strain TA98 and the DNA binding of aromatic compounds in the extracts was assessed by in vitro incubations with CT DNA and rat liver S9 (oxidative activation) or xanthine oxidase (reductive activation) followed by butanol-enhanced (32)P-postlabeling analysis.

Sporadic cryptosporidiosis in a rural population is asymptomatic and associated with contact to cattle.

Fecal samples each followed by a completed questionnaire were obtained from 233 persons representing 80 households. Using the formalinether concentration method combined with the acid-fast staining oocysts of Cryptosporidium were found in 7 (3 %) persons. 63 persons had contact to cattle, and asymptomatic cryptosporidiosis was diagnosed in 6 of them.

Experimental cryptosporidiosis in mice, calves and chicken.

Experimental infections attributed solely to Cryptosporidium were carried out in newborn SPF mice, calves and chicken in order to study the prepatency, patency and incubation periods, describe the clinical symptoms and find and describe any correlations between the association of Cryptosporidium with the intestinal mucosa and presence of pathological lesions. The paper also gives the clinical and paarsitological parameters of Cryptosporidium infection of calves from a field survey and compares them to the results of experimental study.

Rapid immunoassay for detection of Cryptosporidium oocysts.

A direct immunological method by means of latex agglutination (LX) reaction was applied to the demonstration of Cryptosporidium oocysts from stools and gut homogenates. The LX method gave a positive diagnosis for all the specimens judged positive by the modified Ziehl-Neelsen technique, which served as a reference method, The results of the study indicate that the LX method can be adopted as a diagnostic tool for cryptosporidiosis, but further study concerning the specificity and sensitivity of the method is clearly warranted.