Microcystin and pyriproxyfen are toxic to early stages of development in Rhamdia quelen: An experimental and modelling study.

The recent increase of freshwater eutrophication has favored cyanobacteria blooms and consequently the increase of toxins such as microcystin-LR in aquatic environments, but few is know about the associated effect of toxin and other compounds. Pyriproxyfen is an insecticide indicated by WHO (World Health Organization) to control Aedes aegypti mosquito (vector of Dengue, Chikungunya and Zika diseases), however, the effects are not well described to non-target species, such as fish. The early life stages (ELS) of fish are more sensitive to chemical stress due to higher metabolic rate, immature immune system and high superficial area/volume ratio. In the current study, ELS of R. quelen a Neotropical fish were exposed to environmentally realistic concentrations of microcystin (1, 10 and 100 µg L-1; M1, M2 and M3 groups, respectively) from an algal extract, pyriproxyfen (1 and 10 µg L-1, P1 and P2) and their association (co-exposure). The hatching, survival and larvae deformities were analyzed, and applied a mathematical model to evaluate the effects on the population size along further generations. Both compounds were toxic to embryos/larvae of fish, but the effects were more pronounced in M2, P1M2 and P2M1 for hatching and M2, P1M2, P2M1 and P1 for survival. Deformities prevailed in groups exposed to the chemicals at 48 hpf (hours post-fertilization) were suggestions of toxicological interaction in P1M2, P2M1 and P2M2 at 48 and 72 hpf. In 96 hpf, the levels of deformities were lower than in previous times. Model predicted population density over 100 years decreased to lower than 0.5 (50%) in all groups, except for P1M1, indicating risk of extinction. P1M2 had the worse results, followed by M2, P1M3 and P2M1. Cyanobacterial blooms can lead to microcystin-LR levels higher than M2 (10 µg L-1), and the suggestion of toxicological interaction with pyriproxyfen is relevant because both compounds may potentially coexist in aquatic environments. Finally, mathematical models may provide an ecological interpretation of the risk of exposure of fish.

Evolution with age of the acetylcholinesterase activity in rectal suction biopsy in Hirschsprung's disease.

The acetylcholinesterase (AChE) activity in Hirschsprung's disease was analyzed for histochemical patterns according to age. Its evolutional nature was also assessed. Two hundred thirty children (0 to 16 years of age) with acute or chronic obstipation were submitted to rectal suction biopsy for AChE histochemical staining. One hundred nineteen of them showed abnormal AChE activity. Retrospective analysis of those cases permitted us to establish three histochemical patterns: Pattern I, thick nerve trunks present only in the submucosa and, characteristically, absence of AChE activity in the lamina propria. This pattern was predominant in newborn up to 3 months of age and was designated the newborn pattern. Pattern II, thin nerve fibers in the muscularis mucosae and submucosa with a clear infiltration in the lamina propria. This pattern was mainly seen in children older than 1 year of age and was called classical pattern. Pattern III, an intermediate pattern showing morphologic characteristics of the two previous patterns with predominance of one or another, according to the age. A prospective study was also made in 15 children with Hirschsprung's disease who were submitted to suction rectal biopsies at different ages. In this study, a clear evolutional character of the AChE activity was observed from the newborn pattern to the intermediate and finally to the classical pattern.

Pancreatite aguda associada a duplicacao gastrica em crianca. / Acute pancreatitis associated with gastric duplication in a child

Uma crianca do sexo feminino com dois anos e nove meses de idade, foi admitida com o diagnostico de crises recidivantes de pancreatite aguda. A pancreatografia endoscopica nada revelou de anormal. Um estudo radiologico do aparelho digestivo alto demonstrou a existencia de compressao extrinseca do antro gastrico cujas pregas mucosas se apresentavam finas e regulares.Fez-se suspeita diagnostica de duplicacao gastrica confirmada a cirurgia. O estudo radiologico intra-operatorio mostrou comunicacao com o ducto pancreatico. Optou-se por cistojejunostomia em Y de Roux com cura dos sintomas do doente

Atendimento miltiprofissional as criancas com incontinencia fecal pos-cirurgia colo-proctologica. / Multiprofessional assistance of children with fecal incontinence after colon-proctologic surgery

Os autores relatam a experiencia de uma equipe multiprofissional (pediatra, cirurgiao pediatra, assistente social, enfermeira e nutricionista) no atendimento a 17 criancas com incontinencia fecal pos-cirurgia colo-proctologica (9 por megacolo e 8 por anomalia anorretal). Foram realizados estudos morfofuncionais que revelaram somente alteracoes de absorcao de lactose e sacarose, o que motivou emprego de dietas especiais. O esquema basico de tratamento foi: a) diminuir o numero de evacuacoes e/ou aumentar a consistencia das fezes; b) promover disciplina da exoneracao intestinal; c) fortalecer a musculatura abdominoperineal; d) proporcionar apoio a crianca e e) orientar os familiares. Os resultados foram considerados muito satisfatorios