PURPOSE:To evaluate in a long term the morphometric and ultrastructural changes in seminiferous tubules (ST) of normal and diabetic rats, and to correlate any changes with animal age and diabetes duration. METHODS:Sixty male Wistar rats, three months-old, were randomly divided into two groups: 30 non-diabetic controls (N) and 30 alloxan untreated diabetic (D). After one, six and 12 months of follow-up or diabetes induction rats were sacrificed and the testes examined. Morphometric measures of the ST were performed by digital imaging analysis. ST ultrastructure was analyzed by transmission electron microscopy. RESULTS:Sustained hyperglycemic state was observed in all diabetic rats throughout the study. Serum testosterone was also significantly decreased in these animals. The diameter, total area, epithelium area and epithelium thickness of ST were lower and tubular density was higher in diabetic animals. Diabetic rats also showed ultrastructural changes compromising the whole testis including germ-, Sertoli-, and Leydig cells, and also the mithocondria and cellular nuclei. Most frequent of these consisted of vacuolization and/ or accumulation of lipid droplets and electron dense dark material in cell cytoplasm and/or in membranes, cellular degeneration, and apoptosis. Non-diabetic control rats also showed testicular lesions that resemble to the diabetic lesions, although much less severe and with later onset in life of these animals. CONCLUSION:Histopathological changes observed in testes of normal and diabetic rats are closely related to the animal age and/ or duration of the hyperglycemic state, being progressively more severe in animals sacrificed belatedly. These changes may play an important role in male infertility observed in diabetic subjects.

PURPOSE: To determine the number of podocyte, slit diaphragms, slit diaphragm extensions and GBM thickness in diabetic nephropathy. METHODS: Sixty "Rattus Wistar"of both sexes weighing 200-300g were divided in two experimental groups: normal group 10 animals, and alloxan diabetic rats - 50 animals. Alloxan was administered in a single IV dose of 42mg/kg body weight. Body weight, water and food intake, diuresis, and blood and urine glucose were determined in both groups before alloxan injection and two weeks, six and twelve months after alloxan injection. Proteinuria was measured at 12 months in both groups. After 12 months animals were sacrificed, and the right kidney processed for electron microscopy. RESULTS: Clear clinical and laboratory signs of severe diabetes were seen, in all alloxan-diabetic rats at all follow-up times. Glomerular basement membrane (GBM) thickening, podocyte number, and slit diaphragm number and extension were determined. GBM of all diabetic rats was significantly thicker (median=0.29µm; semi-interquartile range=0.065µm) than in the normal rats (0.23µm; 0.035µm). Diabetic rat podocyte number (8; 1), slit diaphragm number (4; 1), and slit diaphragm extension (0.021µm; 0.00435µm) were significantly lower than in normal rats (11; 1) and (7; 1.5), and (0.031µm; 0.0058µm). Diabetic rat proteinuria (0.060mg/24h; 0.037mg/24h) was higher than in normal rats (0.00185mg/24h; 0.00055mg/24h). CONCLUSION: Experimental diabetes is associated with significant (p<0.05) changes in podocyte foot process, slit number, slit diaphragm extension, and GBM thickness.

AimTo determine major sources of microbially produced geosmin in the commercially important aquaculture fish species tilapia.Methods and ResultsAbundance and composition of geosmin-producing bacteria in water and fish biosphere (intestine, digesta, and fins) of Nile tilapia (Oreachromis niloticus) raised in net cages in Brazilian freshwater farms were examined. By combining qPCR of the geosmin synthase geoA gene and 16S rRNA gene amplicon sequencing to identify potential geosmin-producing organisms, we observed that the proportion and composition of geosmin producers appeared to be rather similar in the water, digesta, intestinal mucous, and on skin, making up about 0.1–0.2% of the total bacterial densities. A high proportion of Cyanobacteria and other putative geosmin producers affiliated to the Actinomycetales were identified in the intestinal mucous layer. The main uptake site for geosmin in fish is traditionally assumed to be through the gill surface, but the present results suggest that uptake by the intestinal tract may represent a major source of geosmin uptake in fish.ConclusionThe high abundance of geosmin-producing bacteria in the intestinal mucous layer and digesta may indicate that the digestive system in fish is an important, but hitherto overlooked, source of geosmin and likely other off-flavors in fish.Significance and Impact of Study Tainting of fish by microbially produced off-flavors spoils fish quality and lowers consumer preferences for aquaculture-produced freshwater fish. Our results highlight the potential for the application of probiotic microorganisms for management of the intestinal microflora to improve the fish quality.HIGHLIGHTSOff-flavor producing bacteria are widely abundant in aquaculture.Off-flavor producers found on skin surface of fish.Off-flavor producing bacteria accumulate in the digestive system.Off-flavor producers might release significant amounts of off-flavor during lysis in the gut.Off-flavor uptake through the digestive system might be quantitatively significant.

This study aimed to evaluate the infection by the Austrodiplostomum compactum metacercariae in fishes from the Nova Avanhandava Reservoir, low Tietê river, São Paulo State, Brazil. The parasites were collected from eye (aqueous and vitreous humor), fixed in AFA solution and stained with carmine. The morphometric analysis was performed using a computerized system for analysis of images QWin Lite 2.5 (Leica). Prevalence, mean intensity of infection and abundance of infected fish were calculated. Of the 22 species of fish registered, five were infected by metacercariae: Hoplias malabaricus, Metynnis maculatus, Plagioscion squamosissimus, Satanoperca pappaterra and Schizodon nasutus. Of the 627 fish evaluated, 34% were infected. A higher prevalence was observed in P. squamosissimus and S. pappaterra. Schizodon nasutus and M. maculatus are new hosts reported for A. compactum metacercariae. RESUMO. Infecção por metacercárias de Austrodiplostomum compactum em peixes doReservatório de Nova Avanhandava, rio Tietê, Estado de São Paulo, Brasil. Avaliou-se a infecção por metacercárias de Austrodiplostomum compactum em peixes do Reservatório de Nova Avanhandava, baixo rio Tietê, São Paulo, Brasil. Os parasitos foram coletados nos olhos (humor aquoso e vítreo), fixados com solução de AFA e corados com carmim. A análise morfométrica foi realizada por meio de sistema computadorizado de análise de imagem QWin Lite 2.5 (Leica). A prevalência, intensidade média de infecção e a abundância média dos peixes infectados foram calculadas. Das 22 espécies de peixes capturadas, cinco estavam infectadas por metacercárias: Hoplias malabaricus, Metynnis maculatus, Plagioscion squamosissimus, Satanoperca pappaterra e Schizodon nasutus. De um total de 627 peixes avaliados, 34% estavam infectados. Alta prevalência foi observada em P. squamosissimus e S. pappaterra. Schizodon nasutus e M. maculatus são novos hospedeiros registrados para metacercárias de A. compactum. Palavras-chave: Diplostomidae, trematódeo, novos hospedeiros, olho, parasito.