Childhood exposure due to the Chernobyl accident and thyroid cancer risk in contaminated areas of Belarus and Russia

The thyroid dose due to 131I releases during the Chernobyl accident was reconstructed for children and adolescents in two cities and 2122 settlements in Belarus, and in one city and 607 settlements in the Bryansk district of the Russian Federation. In this area, which covers the two high contamination spots in the two countries following the accident, data on thyroid cancer incidence during the period 1991-1995 were analysed in the light of possible increased thyroid surveillance. Two methods of risk analysis were applied: Poisson regression with results for the single settlements and Monte Carlo (MC) calculations for results in larger areas or sub-populations. Best estimates of both methods agreed well. Poisson regression estimates of 95% confidence intervals (CIs) were considerably smaller than the MC results, which allow for extra-Poisson uncertainties due to reconstructed doses and the background thyroid cancer incidence. The excess absolute risk per unit thyroid dose (EARPD) for the birth cohort 1971-1985 by the MC analysis was 2.1 (95% CI 1.0-4.5) cases per 10(4) person-year Gy. The point estimate is lower by a factor of two than that observed in a pooled study of thyroid cancer risk after external exposures. The excess relative risk per unit thyroid dose was 23 (95% CI 8.6-82) Gy(-1). No significant differences between countries or cities and rural areas were found. In the lowest dose group of the settlements with an average thyroid dose of 0.05 Gy the risk was statistically significantly elevated. Dependencies of risks on age-at-exposure and on gender are consistent with findings after external exposures

Advances in structure elucidation of small molecules using mass spectrometry

The structural elucidation of small molecules using mass spectrometry plays an important role in modern life sciences and bioanalytical approaches. This review covers different soft and hard ionization techniques and figures of merit for modern mass spectrometers, such as mass resolving power, mass accuracy, isotopic abundance accuracy, accurate mass multiple-stage MS(n) capability, as well as hybrid mass spectrometric and orthogonal chromatographic approaches. The latter part discusses mass spectral data handling strategies, which includes background and noise subtraction, adduct formation and detection, charge state determination, accurate mass measurements, elemental composition determinations, and complex data-dependent setups with ion maps and ion trees. The importance of mass spectral library search algorithms for tandem mass spectra and multiple-stage MS(n) mass spectra as well as mass spectral tree libraries that combine multiple-stage mass spectra are outlined. The successive chapter discusses mass spectral fragmentation pathways, biotransformation reactions and drug metabolism studies, the mass spectral simulation and generation of in silico mass spectra, expert systems for mass spectral interpretation, and the use of computational chemistry to explain gas-phase phenomena. A single chapter discusses data handling for hyphenated approaches including mass spectral deconvolution for clean mass spectra, cheminformatics approaches and structure retention relationships, and retention index predictions for gas and liquid chromatography. The last section reviews the current state of electronic data sharing of mass spectra and discusses the importance of software development for the advancement of structure elucidation of small molecules

Methane bursts as a trigger for intermittent lake-forming climates on post-Noachian Mars

Lakes existed on Mars later than 3.6 billion years ago, according to sedimentary evidence for deltaic deposition. The observed fluviolacustrine deposits suggest that individual lake-forming climates persisted for at least several thousand years (assuming dilute flow). But the lake watersheds’ little-weathered soils indicate a largely dry climate history, with intermittent runoff events. Here we show that these observational constraints, although inconsistent with many previously proposed triggers for lake-forming climates, are consistent with a methane burst scenario. In this scenario, chaotic transitions in mean obliquity drive latitudinal shifts in temperature and ice loading that destabilize methane clathrate. Using numerical simulations, we find that outgassed methane can build up to atmospheric levels sufficient for lake-forming climates, if methane clathrate initially occupies more than 4% of the total volume in which it is thermodynamically stable. Such occupancy fractions are consistent with methane production by water–rock reactions due to hydrothermal circulation on early Mars. We further estimate that photochemical destruction of atmospheric methane curtails the duration of individual lake-forming climates to less than a million years, consistent with observations. We conclude that methane bursts represent a potential pathway for intermittent excursions to a warm, wet climate state on early Mars

A utilização do preservativo feminino pelas profissionais do sexo

Este estudio tuvo como objetivo investigar el uso del condón femenino (PF) de trabajadoras sexuales registradas en el Departamento Municipal de Salud de la municipalidad de Rio Grande / RS. Es un estudio descriptivo y cuantitativo, realizado en 2009 con 19 mujeres, a través de la aplicación de un cuestionario individual que contiene preguntas sobre los hábitos sexuales y el uso del PF. El estudio fue aprobado por el Comité de Ética de la FURG en opinión N º 53/2009. Los resultados indicaron que 47,30% informó que acompañan a su estado de salud regularmente, el 58% había tenido contacto con este tipo de condones en los servicios de salud y 73,55% no afirman haber adquirido nunca una Infección de Transmisión Sexual (ETS). En cuanto a las prácticas sexuales 68,45% informó del uso de preservativos sólo para prevenir las ETS, las mujeres que ya están utilizando el PF practicaron sexo vaginal y el 47,30% no ve las ventajas y el 52,65% no ve las desventajas en el uso del PF. Es importante entonces que los establecimientos de salud, incluyendo enfermeras profesionales, estén preparados para afrontar los problemas de salud de estas mujeres y asesorarlas sobre la importancia del uso del condón para el mantenimiento de la salud.Este estudo objetivou investigar a utilização do preservativo feminino (PF) pelas profissionais do sexo cadastradas na Secretaria Municipal de Saúde do município do Rio Grande/RS. Trata- se de um estudo quantitativo e descritivo, realizado no ano de 2009 com 19 mulheres, por meio da aplicação de um questionário individual contendo questões sobre hábitos de saúde sexual e utilização do PF. O estudo foi aprovado pelo Comitê de Ética em Pesquisa da Furg sob parecer nº 53/2009. Nos resultados foi encontrado que 47,30% relataram que acompanham a sua situação de saúde regularmente; 58% tiveram contato com este tipo de preservativo no serviço de saúde e 73,55% afirmam nunca terem adquirido alguma DST. Quanto as práticas sexuais 68,45% relataram utilizar apenas o preservativo masculino para se prevenir das DST´s; as mulheres que já utilizam o PF utilizaram no sexo vaginal e 47,30% não vêem as vantagens e 52,65% não vêem desvantagens em usar o PF. É importante então que nas unidades de saúde, os profissionais incluindo os enfermeiros, devem estar preparados para lidar com as questões de saúde dessas mulheres e orientação quanto a importância do uso do preservativo para a manutenção da saúde.ABSTRACT This study aimed to investigate the use of female condom (PF) by sex workers registered with the Municipal Health Department of the municipality of Rio Grande / RS. It is a descriptive and quantitative study, conducted in 2009 with 19 women, through the application of an individual questionnaire containing questions about sexual habits and use of FP. The study was approved by the Ethics Committee of the FURG in opinion No. 53/2009. The results found that 47.30% reported that they check their health status regularly, 58% already had contact with this type of condom in the health service and 73.55% claim never to have acquired an STI. Regarding sexual practices 68.45% reported using condoms only to prevent STDs, women who are already using PF practised vaginal sex and 47.30% do not see the advantages and 52.65% do not see the disadvantages of using the PF. It is important then that the health facilities, professionals including nurses, should be prepared to deal with health issues and counsel these women about the importance of condom use for health maintenance

The presence of Microlobius foetidus cause changes in the antioxidant defense of Urochloa decumbens?

AbstractUrochloa decumbens (Stapf) R. D. Webster (Poaceae) is an exotic species with has spread rapidly through the Cerrado area of Pantanal, Mato Grosso do Sul, Brazil. It has covered the soil aggressively turning it into cultivated pastures. Thus, it has become a challenge to protect native areas due its capacity of exclusion of native species. It has been observed that Microlobius foetidus (Jacq.) M.Sousa & G.Andrade species (Fabaceae) shows a dominant pattern over the development of U. decumbens. This work shows that M. foetidusinterfere on the natural growth of U. decumbens within 10 m ratio. Between 15 and 20 m, it was observed an increase of Importance Value index (IVI) and Relative cover (RC) values. It was also observed a variation on the antioxidant defense system of U. decumbens within 10m ratio from M. foetidus. The enzymes superoxide dismutase, catalase and peroxidase present higher levels of activity then those found for glutathione reductase. This data indicates that M. foetidus may have an effect on U. decumbens, increase the activity of antioxidant enzymes. This effect probably happens as means to neutralize the toxic effects of the oxygen generated due to the presence of allelochemicals, which increases oxidative stress

How changes in coverage affect equity in maternal and child health interventions in 35 Countdown to 2015 countries: an analysis of national surveys.

BACKGROUND: Achievement of global health goals will require assessment of progress not only nationally but also for population subgroups. We aimed to assess how the magnitude of socioeconomic inequalities in health changes in relation to different rates of national progress in coverage of interventions for the health of mothers and children. METHODS: We assessed coverage in low-income and middle-income countries for which two Demographic Health Surveys or Multiple Indicator Cluster Surveys were available. We calculated changes in overall coverage of skilled birth attendants, measles vaccination, and a composite coverage index, and examined coverage of a newly introduced intervention, use of insecticide-treated bednets by children. We stratified coverage data according to asset-based wealth quintiles, and calculated relative and absolute indices of inequality. We adjusted correlation analyses for time between surveys and baseline coverage levels. FINDINGS: We included 35 countries with surveys done an average of 9·1 years apart. Pro-rich inequalities were very prevalent. We noted increased coverage of skilled birth attendants, measles vaccination, and the composite index in most countries from the first to the second survey, while inequalities were reduced. Rapid changes in overall coverage were associated with improved equity. These findings were not due to a capping effect associated with limited scope for improvement in rich households. For use of insecticide-treated bednets, coverage was high for the richest households, but countries making rapid progress did almost as well in reaching the poorest groups. National increases in coverage were primarily driven by how rapidly coverage increased in the poorest quintiles. INTERPRETATION: Equity should be accounted for when planning the scaling up of interventions and assessing national progress. FUNDING: Bill & Melinda Gates Foundation; World Bank; Governments of Australia, Brazil, Canada, Norway, Sweden, and UK