No abstract

Around the world, enteric viruses are often found in surface waters. This study set out to evaluate the occurrence of adenoviruses (AdVs) in water samples, and its relation to different physical, chemical, and bacteriological parameters [total coliform (TC) and fecal coliform (FC), represented by Escherichia coli]. Monthly samples of 500 ml of raw water were collected from May 2011 to June 2013 in eight abstraction points water treatment stations along three stretches of the Sinos River Basin (SRB), in Southern Brazil and, subsequently, were analyzed using real-time polymerase chain reaction (qPCR). AdVs from different species, from human (HAdV), and from other animals (CAV1-2, BAdV, PAdV, and AvAdV) were detected along the three stretches of the basin, indicating fecal contamination from different sources and proving the inefficiency of the wastewater treatment in the waters of the SRB and intensifying the strong influence of human activities that can contribute to the presence of inhibitory substances such as organic acids in surface of these waters. Statistical analyses revealed no significant correlations between the concentrations of TC and FC and the concentrations of AdVs. We observed a small, nonconstant, and unstable correlation between viruses and physicochemical parameters. These correlations were not sufficiently consistent to establish a reliable association; therefore, this study corroborates that only the viral assay itself is reliable for the diagnosis of fecal contamination by viruses in environmental samples.

Despite the recent increase in studies on franciscana dolphin (Pontoporia blainvillei) molecular biology, there has been no published karyotype information, as opportunities for sampling live individuals are very rare. In the present study, the diploid number of the species was established from corneal cell cultures of 2 newborn male franciscanas live stranded (2n = 44). From the comparison of the chromosomal number to the cetacean karyotype phylogeny, we suggest that the most parsimonious hypothesis is that the ancestral character state in the group is the diploid number of 42, with an extra chromosome pair appearing independently twice during cetacean evolution, once in the suborder Odontoceti and once in the suborder Mysticeti. This information on chromosomal number may be useful to future genetic mapping projects of the species.

Climate variables may interfere with the environmental persistence and spread of pathogenic microorganisms. This study aimed to investigate the occurrence of human adenovirus (HAdV) and total and thermotolerant coliforms in treated and untreated water and report gastroenteritis cases in seven cities located in the hydrographic basin of the Sinos River (HBSR), Southern Brazil. The data on water quality from samples collected at catchment areas of HBSR from March to December 2011 were compared with precipitation records, virus detection rates and viral loads, and information on enteric diseases among residents of the region. There was a marked increase in precipitation intensity in April, July, and August and a decrease in May and November. The number of HAdV genome copies (gc) in untreated water ranged from 2.1×10(8) gc/L in June to 7.8×10(1) gc/L in December, and in treated water, from 6.3×10(4) gc/L in September to 4.1×10(1) gc/L in November. The most probable number (MPN) of total coliforms ranged from 5×10(1) MPN/100 mL in December to 2.4×10(5) MPN/100 mL in July, and thermotolerant coliforms ranged from 1×10(1) MPN/100 mL in August to 6.9×10(4) MPN/100 mL in July. A total of 79 hospital admissions due to gastroenteritis were registered in the cities studied. The results for coliforms in untreated water demonstrate deficits in sanitation and wastewater treatment. These findings also indicate a possible relationship between the occurrence of rainfalls after dry periods and an increase in the number of gastroenteritis cases and in HAdV load quantified in surface water collected for conventional potabilization.

Presently, there is no information about the functionality of the immune system in the franciscana dolphin (Pontoporia blainvillei), a small dolphin from southern Brazil. As in the case of the franciscana, the population of southern right whale (Eubalaena australis) which inhabits Brazilian waters has not yet been surveyed in what concerns MHC expression. For the first time it was possible to observe the DQB gene expression in skin of these two species of cetacean using RT-PCR. Skin pieces of the animals were collected to RNA extraction. The fragment corresponding to DQB exon 2 was amplified, cloned and sequenced. A total of five alleles were found, one to franciscana and four to southern right whale. The observed dN/dS ratio of 2.77 (P = 0.03) suggests that this gene is under balancing selection pressure (positive Darwinian selection). The sequences indicate that, in both species analysed, the DQB gene is functional.