Evaluation of induced biological effects in rats by continuous and natural gamma radiation using a physical simulator.

PURPOSE: The effects of radioactivity on human health have been debated for many years but there are still important gaps that need to be addressed especially related to the effects of high natural background radiation on the local population. The beach of Meaípe, in the city of Guarapari (Brazil), emits natural gamma radiation due to the presence of monazite sands. We aimed to investigate the effects of gamma radiation doses on the biological system of wistar rats using a physical simulator of gamma radiation designed using Meaípe monazite sands. METHODS: Female Wistar rats were divided into three groups, submitted to no radiation (control group) and to continuous radiation levels, one of very high level (20 µSv h-1) and another of high level (3.6 µSv h-1). The three group of animals were monitored weekly for 3 months and at the end of the study the animals were sacrificed, and the organs were extracted and weighed for anthropometric, oxidative stress and histological evaluations. RESULTS: Exposure to radiation released by the monazite sands did not cause anthropometric alterations or blood pressure change in the animals. Similarly, there was no change in the quantification of ovarian follicles between the radiation groups and the control group. There was no difference in the oxidative stress quantification by the thiobarbituric acid reactive substance and advanced oxidation protein product methods in the ovaries. There were no evidenced damages in the structure of the renal tissue. It was observed the presence of granulomas in the hepatic tissue and alterations in the nuclei of the hepatocytes. CONCLUSIONS: Our results suggest that the continuous exposure of females rats to 3.6 and 20 µSv h-1 doses of gamma radiation slightly affected the hepatic tissue, but did not alter the histological parameters in the kidneys and ovaries and oxidative stress.

Comparação da atividade de ácidos graxos essenciais e biomembrana na microbiota de feridas crônicas infectadas / Comparison of the activity of fatty essential acids and biomembrane in the microbiota of infected chronic wounds

Em pessoas curadas de hanseníase, as úlceras em membros inferiores representam um desafio aos profissionais, por serem crônicas, infectadas e recorrentes. Esta pesquisa teve como objetivo comparar a ação de uma biomembrana de látex (Biocure®) e de um produto à base de AGE (Dersani®) na microbiota de feridas crônicas infectadas, em pessoas que receberam alta do tratamento para hanseníase. Trata-se de pesquisa realizada no Hospital de Dermatologia Sanitária, de Goiânia (GO), no período de fevereiro a outubro de 2007, na qual participaram 8 pessoas curadas de hanseníase, com 19 feridas infectadas, que foram, alocadas aleatoriamente em grupo A (tratado com Dersani®) e grupo B (tratado com Biocure®). Foram identificados Staphylococcus aureus (50%), Pseudomonas aeruginosa (35,7%), Proteus vulgaris (8,2%), Enterobacter aerogenes (3,3%) e Escherichia coli (2,7%). Os resultados obtidos in vivo sugerem que o Dersani® tenha efeito antimicrobiano positivo sobre Enterobacter aerogenes e o Biocure® sobre Pseudomonas aeruginosa. Os resultados in vitro mostraram ausência de atividade de ambos os produtos sobre os microrganismos isolados das lesões.

For patients cured of leprosy, low-limb ulcers represent a challenge to healthcare workers, for being chronic, infected, and recurrent. This study aimed to compare the latex biomembrane (Biocure TM) and an EFA-based product (Dersani TM) action on the microbiota of infected chronic wounds, in patients discharged from the treatment of leprosy. This is a research carried out at Hospital de Dermatologia Sanitária, in Goiânia-GO, from February to October 2007, in which 8 individuals cured of leprosy, having 19 infected wounds, were randomly allocated in group A (Dersani TM) and group B (Biocure TM). Staphylococcus aureus (50%), Pseudomonas aeruginosa (35.7%), Proteus vulgaris (8.2%), Enterobacter aerogenes (3.3%), and Escherichia coli (2.7%) were isolated. The results obtained in vivo suggest that Dersani TM has a positive antimicrobial effect against Enterobacter aerogenes and Biocure TM against Pseudomonas aeruginosa, despite the in vitro results having shown absence of antimicrobial activity for both products against microorganisms standard and isolated from the wounds.