Bacteriocins in S. mutans strains isolated from children with and without dental caries: biotypes and sensitivity to antibiotics.

The aim of this study was to determine the production of bacteriocins in the Streptococcus mutans strains isolated from children with and without dental caries. With this purpose the dmft index was determined and non-stimulated saliva was collected from 53 3- to 5-year-old children. The samples were cultured on Mitis Salivarius Bacitracin agar and incubated anaerobically for two days at 37 degrees C.

Hyperendemic Cryptosporidium and Giardia in households lacking municipal sewer and water on the United States-Mexico border.

This study identified differences in the epidemiology of Giardia and Cryptosporidium infection for low-income populations residing on the United States-Mexico border. Participation included 77 households in three communities lacking adequate municipal water and sewage services. The household was the unit of analysis and sampling was from household biosolid waste from newly installed composting toilets.

Isolation and genotyping of Helicobacter pylori from untreated municipal wastewater.

For this study, we isolated Helicobacter pylori from wastewater by a series of steps beginning with immunomagnetic separation and cell culture. After Gram staining and three standard microbial tests, the 16S rRNA sequences of a total of 23 out of 37 putative H. pylori isolates were verified by PCR.