Endonuclease IV Is the Main Base Excision Repair Enzyme Involved in DNA Damage Induced by UVA Radiation and Stannous Chloride

Stannous chloride (SnCl2) and UVA induce DNA lesions through ROS. The aim of this work was to study the toxicity induced by UVA preillumination, followed by SnCl2 treatment. E. coli BER mutants were used to identify genes which could play a role in DNA lesion repair generated by these agents. The survival assays showed (i) The nfo mutant was the most sensitive to SnCl2; (ii) lethal synergistic effect was observed after UVA pre-illumination, plus SnCl2 incubation, the nfo mutant being the most sensitive; (iii) wild type and nfo mutants, transformed with pBW21 plasmid (nfo+) had their survival increased following treatments. The alkaline agarose gel electrophoresis assays pointed that (i) UVA induced DNA breaks and fpg mutant was the most sensitive; (ii) SnCl2-induced DNA strand breaks were higher than those from UVA and nfo mutant had the slowest repair kinetics; (iii) UVA + SnCl2 promoted an increase in DNA breaks than SnCl2 and, again, nfo mutant displayed the slowest repair kinetics. In summary, Nfo protects E. coli cells against damage induced by SnCl2 and UVA + SnCl2

Endonuclease IV Is the Main Base Excision Repair Enzyme Involved in DNA Damage Induced by UVA Radiation and Stannous Chloride

Stannous chloride (SnCl 2 ) and UVA induce DNA lesions through ROS. The aim of this work was to study the toxicity induced by UVA preillumination, followed by SnCl 2 treatment. E. coli BER mutants were used to identify genes which could play a role in DNA lesion repair generated by these agents. The survival assays showed (i) The nfo mutant was the most sensitive to SnCl 2 ; (ii) lethal synergistic effect was observed after UVA pre-illumination, plus SnCl 2 incubation, the nfo mutant being the most sensitive; (iii) wild type and nfo mutants, transformed with pBW21 plasmid (nfo + ) had their survival increased following treatments. The alkaline agarose gel electrophoresis assays pointed that (i) UVA induced DNA breaks and fpg mutant was the most sensitive; (ii) SnCl 2 -induced DNA strand breaks were higher than those from UVA and nfo mutant had the slowest repair kinetics; (iii) UVA + SnCl 2 promoted an increase in DNA breaks than SnCl 2 and, again, nfo mutant displayed the slowest repair kinetics. In summary, Nfo protects E. coli cells against damage induced by SnCl 2 and UVA + SnCl 2

H1N1pdm Influenza Infection in Hospitalized Cancer Patients: Clinical Evolution and Viral Analysis

BACKGROUND: The novel influenza A pandemic virus (H1N1pdm) caused considerable morbidity and mortality worldwide in 2009. The aim of the present study was to evaluate the clinical course, duration of viral shedding, H1N1pdm evolution and emergence of antiviral resistance in hospitalized cancer patients with severe H1N1pdm infections during the winter of 2009 in Brazil. METHODS: We performed a prospective single-center cohort study in a cancer center in Rio de Janeiro, Brazil. Hospitalized patients with cancer and a confirmed diagnosis of influenza A H1N1pdm were evaluated. The main outcome measures in this study were in-hospital mortality, duration of viral shedding, viral persistence and both functional and molecular analyses of H1N1pdm susceptibility to oseltamivir. RESULTS: A total of 44 hospitalized patients with suspected influenza-like illness were screened. A total of 24 had diagnosed H1N1pdm infections. The overall hospital mortality in our cohort was 21%. Thirteen (54%) patients required intensive care. The median age of the studied cohort was 14.5 years (3-69 years). Eighteen (75%) patients had received chemotherapy in the previous month, and 14 were neutropenic at the onset of influenza. A total of 10 patients were evaluated for their duration of viral shedding, and 5 (50%) displayed prolonged viral shedding (median 23, range=11-63 days); however, this was not associated with the emergence of a resistant H1N1pdm virus. Viral evolution was observed in sequentially collected samples. CONCLUSIONS: Prolonged influenza A H1N1pdm shedding was observed in cancer patients. However, oseltamivir resistance was not detected. Taken together, our data suggest that severely ill cancer patients may constitute a pandemic virus reservoir with major implications for viral propagation

Desafíos políticos de los países de inmigración

13 págs.-- Publicado en "Confluencia XXI. Revista de Pensamiento Político" (México), nº 3 (Oct-Dic 2008) bajo el título monográfico "Migrantes: ¿Por qué se van? ¿Por qué se quedan?".Las migraciones, una práctica tan antigua como la propia condición humana, se han convertido en un factor estructural de primer orden, en uno de los macrofenómenos más definitorios de nuestra época y en un complejo reto para las sociedades contemporáneas. En prácticamente todos los países del mundo, todo lo que concierne a este complejo fenómeno ocupa un lugar destacado en la agenda política. La gestión, el control y la integración de los movimientos internacionales de personas se presentan como un policy field de creciente y prioritaria relevancia. No se trata, sin embargo, de una cuestión de mera moda: el número de países implicados de manera significativa en las migraciones internacionales ha aumentado considerablemente, hasta el punto de que resulta realmente difícil encontrar algún Estado que no sea bien un país de inmigración, bien un país de emigración o bien ambas cosas a la vez, cuando no al menos un país de tránsito. No ha de extrañar entonces que la mayoría de los gobiernos haya tomado conciencia de la necesidad de ofrecer una respuesta en términos legales e institucionales a un fenómeno de carácter permanente que puede llegar a alterar la estructura demográfica, social, cultural, económica y laboral de un país. Dada la complejidad de la cuestión, y por cuestiones de economía argumentativa, aquí se abordará de manera fundamental desde la perspectiva de los países receptores, que, por lo demás, es también la adoptada en forma habitual por los países europeos que registran mayor inmigración. Sin embargo, el fenómeno migratorio es fundamentalmente transnacional y tiene fehacientes repercusiones en los países de emigración.Peer reviewe

Estudo sobre a ocorrência de fungos e aflatoxina B1 na dieta de bovinos leiteiros em São Paulo

A qualidade da dieta ofertada às vacas em lactação é uma preocupação dos agentes de saúde devido à possibilidade da detecção de micotoxinas prejudiciais a saúde humana e animal. Os objetivos do trabalho foram avaliar o perfil da micobiota, determinar a atividade de água (Aa) e a ocorrência natural de aflatoxina B1 (AFB1) em dietas ofertadas a vacas em lactação de fazendas leiteiras no estado de São Paulo, Brasil. As amostragens das dietas foram realizadas diretamente dos cochos de lote de 15 vacas, em dois dias consecutivos com intervalos de 24h e a cada 15 dias, perfazendo um período de 45 dias de amostragens por fazenda. A purificação e determinação de AFB1 foram realizadas em colunas de imunoafinidade e Cromatografia Líquida de Alta Eficiência (CLAE). O estudo da micobiota presente nas amostras das dietas (288) revelou que as leveduras foram predominantes em todas as dietas (83,97 a 99,98%). Foram isolados 15 gêneros de fungos filamentosos, com os gêneros Aspergillus spp (20,09%), Fusarium spp (14,16%) e Penicillium spp (11,48%) os mais prevalentes. As contagens de Unidades Formadoras de Colônias por grama de alimento (UFC. g-1) variaram de 102 a 1011. A atividade de água das amostras variou entre 0,91 a 0,98. Foi detectada a presença de AFB1 em 31,44% das amostras com teores entre 1,68 a 194,51μg.kg-1. Medidas de boas práticas de produção, estocagem e utilização devem ser tomadas para diminuir a ocorrência de AFB1 nas dietas ofertadas às vacas em lactação

Master athletes have longer telomeres than age-matched non-athletes. A systematic review, meta-analysis and discussion of possible mechanisms.

The aim of this systematic review and meta-analysis was 1) to assess whether master athletes have longer telomeres than age-matched non-athletes and 2) discuss possible underlying mechanisms underlying telomere length preservation in master athletes. A literature search was performed in PubMed, Web of Science, Scopus and SPORTDiscus up to August 2020. Only original articles published in peer-reviewed journals that compared telomere length between master athletes and aged-matched non-athletes were included. Eleven studies fulfilled eligibility criteria and were included in the final analysis. Overall, 240 master athletes (51.9±7.5 years) and 209 age-matched non-athletes (50.1±9.1 years) were analyzed. Master athletes had been participating in high-level competitions for approximately 16.6 years. Pooled analyses revealed that master athletes had longer telomeres than aged-matched non-athletes (SMD=0.89; 95% CI=0.45 to 1.33; p<0.001). Master athletes showed lower pro-oxidant damage (SMD=0.59; 95% CI=0.26 to 0.91; p<0.001) and higher antioxidant capacity (SMD=-0.46; 95% CI=-0.89 to -0.03; p=0.04) than age-matched non-athletes. Further, greater telomere length in master athletes is associated with lower oxidative stress and chronic inflammation, and enhanced shelterin protein expression and telomerase activity. In conclusion, 1) master athletes have longer telomeres than age-matched non-athletes, which may be the result of 2) lower levels of oxidative stress and chronic inflammation, and elevated shelterin expression and telomerase activity