Influencia del campo magnético sobre el crecimiento de microorganismos patógenos ambientales aislados en el Archivo Nacional de la República de Cuba / Influence of magnetic field on the growth of pathogen microorganisms isolated from the indoor environment at the Archivo Nacional de la República de Cuba

Introducción. En el Archivo Nacional de la República de Cuba, existe contaminación electromagnética y la influencia del campo magnético oscilante de frecuencia extremadamente baja podría cuantificarse con microorganismos patógenos aislados de su ambiente interior. Objetivo. Cuantificar la influencia de este tipo de campo magnético sobre el crecimiento de microorganismos patógenos aislados del ambiente en el Archivo Nacional de la República de Cuba. Materiales y métodos. Se emplearon cinco microorganismos: Streptococcus sp. (1), Listeria sp. (2) y Candida guillermondii (3), aislados en el Archivo, así como Escherichia coli ATCC 25922 (4) y Saccharomyces cerevisiae (5), como referencia. Se les aplicó un campo magnético oscilante de frecuencia extremadamente baja de 60 Hz/220 V de 3 mT durante dos horas, en tres tubos de cultivo con agua destilada y con caldo nutriente. Después se inocularon 0,1 ml en placas de Petri con los medios de cultivo agar CromoCen SC (1 y 2), agar de dextrosa y papa (3), agar CromoCen CC 4227 (4) y agar con extracto de malta (5). Las colonias se contaron (log UFC/ml) mediante el procesamiento digital de las imágenes de las placas de Petri empleando el programa MatLab ® . Resultados. Se observó una estimulación significativa (p=0,05) de la cantidad de colonias tratadas con respecto a los controles, siendo mayor en el caldo nutriente que en el agua destilada y más en las bacterias (caldo nutriente-colonias tratadas: 9,43 a 10,62 UFC/ml) que en las levaduras (caldo nutriente-colonias tratadas: 8,31 a 8,79 UFC/ml). La estimulación se produjo en orden decreciente así: Listeria sp., E. coli ATCC 25922, Streptococcus sp., C. guillermondii y S. cerevisiae . Conclusión. Se concluyó que el campo magnético aplicado tuvo un efecto estimulante sobre los microorganismos estudiados, lo cual potencia el riesgo para la salud del personal y los visitantes del Archivo Nacional de la República de Cuba.

Introduction: Electromagnetic pollution has been detected at the Archivo Nacional de la República de Cuba and the influence of extremely low frequency magnetic fields could be quantified with pathogenic microorganisms isolated from the indoor environment. Objective: To quantify the influence of an extremely low frequency magnetic field on the growth of pathogenic microorganisms isolated from the environment at the Archivo Nacional. Materials and methods: We used five microorganisms isolated at the Archivo Nacional: Streptococcus sp. (1), Listeria sp. (2) and Candida guillermondii (3), and Escherichia coli ATCC 25922 (4) and Saccharomyces cerevisiae (5) as references. We applied this magnetic field of extremely low frequency, 60 Hz/220 V (3 mT), for two hours to these microorganisms on three culture tubes with distilled water and nutrient broth. Then we inoculated 0.1 mL in the following solid culture mediums on Petri dishes: CromoCen SC Agar (1 and 2), Potato Dextrose Agar (3), CromoCen DC 4227 (4) and Malt Extract Agar (5). The colonies were counted (log CFU/mL) by digital processing of the images of Petri dishes using the MatLab ® tool. Results: We observed a statistically significant stimulation (p=0.05) in the quantity of treated colonies as compared to controls, which was higher in nutrient broth than in distilled water, and in bacteria (nutrient broth and treated colonies: 9.43 to 10.62 CFU/mL) as compared with yeasts (nutrient broth-treated colonies: 8.31 to 8.79 CFU/mL). In decreasing order, stimulation was as follows: Listeria sp., E. coli ATCC 25922, Streptococcus sp., C. guillermondii and S. cerevisiae . Conclusion: We concluded that the magnetic field applied had a stimulating effect on the microorganisms under study, which increases the risk to the health of staff and visitors at the Archivo Nacional .

[Influence of magnetic field on the growth of pathogen microorganisms isolated from the indoor environment at the Archivo Nacional de la República de Cuba]. / Influencia del campo magnético sobre el crecimiento de microorganismos patógenos ambientales aislados en el Archivo Nacional de la República de Cuba.

INTRODUCTION: Electromagnetic pollution has been detected at the Archivo Nacional de la República de Cuba and the influence of extremely low frequency magnetic fields could be quantified with pathogenic microorganisms isolated from the indoor environment. OBJECTIVE: To quantify the influence of an extremely low frequency magnetic field on the growth of pathogenic microorganisms isolated from the environment at the Archivo Nacional. MATERIALS AND METHODS: We used five microorganisms isolated at the Archivo Nacional: Streptococcus sp. (1), Listeria sp. (2) and Candida guillermondii (3), and Escherichia coli ATCC 25922 (4) and Saccharomyces cerevisiae (5) as references. We applied this magnetic field of extremely low frequency, 60 Hz/220 V (3 mT), for two hours to these microorganisms on three culture tubes with distilled water and nutrient broth. Then we inoculated 0.1 mL in the following solid culture mediums on Petri dishes: CromoCen SC Agar (1 and 2), Potato Dextrose Agar (3), CromoCen DC 4227 (4) and Malt Extract Agar (5). The colonies were counted (log CFU/mL) by digital processing of the images of Petri dishes using the MatLab ® tool. RESULTS: We observed a statistically significant stimulation (p=0.05) in the quantity of treated colonies as compared to controls, which was higher in nutrient broth than in distilled water, and in bacteria (nutrient broth and treated colonies: 9.43 to 10.62 CFU/mL) as compared with yeasts (nutrient broth-treated colonies: 8.31 to 8.79 CFU/mL). In decreasing order, stimulation was as follows: Listeria sp., E. coli ATCC 25922, Streptococcus sp., C. guillermondii and S. cerevisiae . CONCLUSION: We concluded that the magnetic field applied had a stimulating effect on the microorganisms under study, which increases the risk to the health of staff and visitors at the Archivo Nacional .

Atitude dos estudantes de ensino secundário à prática da atividade física / Attitude of secondary school students to the practice of physical activity

Vários estudos epidemiológicos têm evidenciado a importância da atividade física comprovando a sua contribuição para uma vida saudável e o bem-estar do indivíduo. Neste sentido, é importante que os jovens adquiram conhecimentos, gosto e motivação pela atividade física e façam da sua prática um estilo de vida, uma vez que a adoção de comportamentos protetores da saúde na infância e adolescência, promovem uma vida com mais qualidade, podendo também determinar uma vida mais saudável na idade adulta e na velhice. Neste âmbito, as atitudes revestem-se de grande importância, porque podem predizer a motivação para a aprendizagem e o envolvimento dos mais jovens nas atividades físicas e desportivas. Os objetivos deste estudo são avaliar as atitudes dos estudantes do ensino secundário face à atividade física e identificar quais os fatores que interferem nas mesmas. Desenvolveu-se um estudo não ­ experimental, descritivo, analítico, transversal e de natureza quantitativa. Foi selecionada uma amostra não probabilística por acessibilidade, constituída pelos estudantes do ensino secundário, de um Agrupamento de escolas do Distrito da Guarda, constituída por 95 estudantes com idades compreendidas entre os 15 e os 23 anos, com uma média de idades de 17.48 anos. Relativamente ao instrumento de colheita de dados, a escolha recaiu num questionário elaborado especificamente para o estudo e numa escala traduzida e validada na população portuguesa para avaliar as atitudes face à atividade física e ao desporto, Escala de Actitudes hacia la Actividad Física y el Deporte (Escala de Atitudes face à Atividade Física e o Desporto), desenvolvida por Dosil (2002). A aplicação da escala de atitudes face à atividade física e desporto permitiu observar que 36.8% dos estudantes situaram-se num nível médio inferior, seguidos de 30.5% que se posicionaram no nível médio e de 23.2% que ocuparam o nível inferior, 3.6% dos estudantes situaram-se no nível médio superior e 3.2% no nível superior. Concluiu-se que os estudantes do ensino secundário que apresentam atitudes mais positivas face à prática da atividade física, são os estudantes mais novos; do género masculino; a frequentar o curso científico-humanístico; consumidores de bebidas alcoólicas e que praticam atividade física. Verificam-se ainda atitudes mais positivas nos indivíduos em que o seu grupo de pares pratica atividade física. 6 Os resultados desta investigação apontam para a necessidade de planear algumas atividades que envolvam os estudantes que participaram no estudo, a escola, a família e o Centro de Saúde, enquanto elementos promotores de estilos de vida saudáveis e de forma a fomentar atitudes mais positivas face à prática de atividade física.

Several epidemiological studies have shown the importance of physical activity confirming its contribution to a healthy lifestyle and well-being of the individual. Therefore, it is important that young people acquire knowledge, fondness and motivation for physical activity and make their practice a way of life, since the adoption of protective health behaviors in childhood and adolescence promote a life with more quality, and may also determine a healthier life in adulthood and old age. In this context, the attitudes are of great importance because they can predict the motivation for learning and the involvement of the youngest in sport and physical activities. The goals of this study are to assess the attitudes of high school students regarding physical activity and identify which factors interfere in those activities. It was developed a non experimental, descriptive, analytical, cross-sectional, and quantitative in nature, study. For the purpose it was selected a non-probability convenience sampling, composed of high school students from a grouping of schools in the district of Guarda, consisting of 95 students aged between 15 and 23 years, with a mean age of 17.48 years. Regarding the data collection instrument, the choice fell on a questionnaire developed specifically for the study, and of a scale translated and validated in the Portuguese population to evaluate the attitudes towards physical activity and sport, Escala de Actitudes hacia la Actividad Física y el Deporte (Attitudes toward Physical Activity and Sport Scale), developed by Dosil (2002). The application of the Attitudes toward Physical Activity and Sport scale allowed us to notice that 36.8% of the students were found in a middle inferior level, followed by 30.5% who were positioned at the middle level and 23.2% who occupied the lower level, 3.6% of the students stood in the middle superior level and 3.2% at the top level. It has been concluded that high school students who have the most positive attitudes towards physical activity are younger students, male gender; attending the scientific and humanistic course; alcohol users and that perform physical activity. There are still more positive attitudes among individuals whose peer group practices physical activity. The results of this research suggests the need to plan some activities involving students that participated in the study, the school, the family and the Health Centre, as promoter 8 elements of healthy lifestyles in order to stimulate most positive attitudes to practice physical activity