Evolución de la contaminación del aire e impacto de los programas de control en tres megaciudades de América Latina

En este trabajo se discute la problemática de la contaminación del aire en tres megaciudades de América Latina (Ciudad de México, São Paulo y Santiago); en particular se revisan los programas de control de la contaminación atmosférica que han puesto en marcha los gobiernos de esas ciudades y la evolución de los niveles de contaminantes durante el periodo 1988-1995 en Santiago de Chile y São Paulo, y hasta 1997 en la Ciudad de México, con el objeto de evaluar el impacto de esos programas. En las tres megaciudades se observó un descenso en las concentraciones de PTS, PM10, SO2, NO2, CO y O3 durante el periodo mencionado, aunque la mayoría de los contaminantes siguen rebasando la norma de calidad del aire. Cabe destacar que el mayor impacto de los programas ha sido sobre los niveles de SO2. Se recomienda el desarrollo de políticas de transporte sostenible; en ese sentido, en la Conferencia Europea de Ministros del Transporte la Organización para la Cooperación y el Desarrollo Económico (OCDE) propuso distintas estrategias. Por otra parte, la participación ciudadana es importante al tomar decisiones relacionadas con las políticas de transport

BTA, a novel reagent for DNA attachment on glass and efficient generation of solid-phase amplified DNA colonies

The tricarboxylate reagent benzene-1,3,5-triacetic acid (BTA) was used to attach 5′-aminated DNA primers and templates on an aminosilanized glass surface for subsequent generation of DNA colonies by in situ solid-phase amplification. We have characterized the derivatized surfaces for the chemical attachment of oligonucleotides and evaluate the properties relevant for the amplification process: surface density, thermal stability towards thermocycling, functionalization reproducibility and storage stability. The derivatization process, first developed for glass slides, was then adapted to microfabricated glass channels containing integrated fluidic connections. This implementation resulted in an important reduction of reaction times, consumption of reagents and process automation. Innovative analytical methods for the characterization of attached DNA were developed for assessing the surface immobilized DNA content after amplification. The results obtained showed that the BTA chemistry is compatible and suitable for forming highly dense arrays of DNA colonies with optimal surface coverage of about 10 million colonies/cm2 from the amplification of initial single-template DNA molecules immobilized. We also demonstrate that the dsDNA colonies generated can be quantitatively processed in situ by restriction enzymes digestion. DNA colonies generated using the BTA reagent can be used for further sequence analysis in an unprecedented parallel fashion for low-cost genomic studie

BTA, a novel reagent for DNA attachment on glass and efficient generation of solid-phase amplified DNA colonies

The tricarboxylate reagent benzene-1,3,5-triacetic acid (BTA) was used to attach 5′-aminated DNA primers and templates on an aminosilanized glass surface for subsequent generation of DNA colonies by in situ solid-phase amplification. We have characterized the derivatized surfaces for the chemical attachment of oligonucleotides and evaluate the properties relevant for the amplification process: surface density, thermal stability towards thermocycling, functionalization reproducibility and storage stability. The derivatization process, first developed for glass slides, was then adapted to microfabricated glass channels containing integrated fluidic connections. This implementation resulted in an important reduction of reaction times, consumption of reagents and process automation. Innovative analytical methods for the characterization of attached DNA were developed for assessing the surface immobilized DNA content after amplification. The results obtained showed that the BTA chemistry is compatible and suitable for forming highly dense arrays of DNA colonies with optimal surface coverage of about 10 million colonies/cm(2) from the amplification of initial single-template DNA molecules immobilized. We also demonstrate that the dsDNA colonies generated can be quantitatively processed in situ by restriction enzymes digestion. DNA colonies generated using the BTA reagent can be used for further sequence analysis in an unprecedented parallel fashion for low-cost genomic studies

Healthy lifestyle and risk of breast cancer for indigenous and non-indigenous women in New Zealand: a case control study.

BACKGROUND: The reasons for the increasing breast cancer incidence in indigenous Māori compared to non-Māori New Zealand women are unknown. The aim of this study was to assess the association of an index of combined healthy lifestyle behaviours with the risk of breast cancer in Māori and non-Māori women. METHODS: A population-based case-control study was conducted, including breast cancer cases registered in New Zealand from 2005-2007. Controls were matched by ethnicity and 5-year age bands. A healthy lifestyle index score (HLIS) was generated for 1093 cases and 2118 controls, based on public health and cancer prevention recommendations. The HLIS was constructed from eleven factors (limiting red meat, cream, and cheese; consuming more white meat, fish, fruit and vegetables; lower alcohol consumption; not smoking; higher exercise levels; lower body mass index; and longer cumulative duration of breastfeeding). Equal weight was given to each factor. Logistic regression was used to estimate the associations between breast cancer and the HLIS for each ethnic group stratified by menopausal status. RESULTS: Among Māori, the mean HLIS was 5.00 (range 1-9); among non-Māori the mean was 5.43 (range 1.5-10.5). There was little evidence of an association between the HLIS and breast cancer for non-Māori women. Among postmenopausal Māori, those in the top HLIS tertile had a significantly lower odds of breast cancer (Odds Ratio 0.47, 95% confidence interval 0.23-0.94) compared to those in the bottom tertile. CONCLUSION: These findings suggest that healthy lifestyle recommendations could be important for reducing breast cancer risk in postmenopausal Māori women

Air pollution attributable postneonatal infant mortality in U.S. metropolitan areas: a risk assessment study

BACKGROUND: The impact of outdoor air pollution on infant mortality has not been quantified. METHODS: Based on exposure-response functions from a U.S. cohort study, we assessed the attributable risk of postneonatal infant mortality in 23 U.S. metropolitan areas related to particulate matter <10 μm in diameter (PM(10)) as a surrogate of total air pollution. RESULTS: The estimated proportion of all cause mortality, sudden infant death syndrome (normal birth weight infants only) and respiratory disease mortality (normal birth weight) attributable to PM(10 )above a chosen reference value of 12.0 μg/m(3 )PM(10 )was 6% (95% confidence interval 3–11%), 16% (95% confidence interval 9–23%) and 24% (95% confidence interval 7–44%), respectively. The expected number of infant deaths per year in the selected areas was 106 (95% confidence interval 53–185), 79 (95% confidence interval 46–111) and 15 (95% confidence interval 5–27), respectively. Approximately 75% of cases were from areas where the current levels are at or below the new U.S. PM(2.5 )standard of 15 μg/m(3 )(equivalent to 25 μg/m(3 )PM(10)). In a country where infant mortality rates and air pollution levels are relatively low, ambient air pollution as measured by particulate matter contributes to a substantial fraction of infant death, especially for those due to sudden infant death syndrome and respiratory disease. Even if all counties would comply to the new PM(2.5 )standard, the majority of the estimated burden would remain. CONCLUSION: Given the inherent limitations of risk assessments, further studies are needed to support and quantify the relationship between infant mortality and air pollution

Breast cancer in Mexican women: an epidemiological study with cervical cancer control

OBJETIVO: O câncer de mama (CM) é uma das principais causas de morte por câncer em mulheres, no México, com aumento da incidência e da mortalidade nos últimos anos. O estudo realizado objetivou identificar possíveis fatores de risco relacionados ao CM. MÉTODOS: Realizou-se um estudo epidemiológico de casos hospitalares de CM e de controles hospitalares com câncer cérvico-uterino (CACU) em oito hospitais de terceiro nível, na Cidade do México. Foram estudados 353 casos incidentes de CM e 630 controles com CACU, identificados entre mulheres com menos de 75 anos de idade, residentes na área metropolitana da Cidade do México pelo menos há um ano. O diagnóstico foi confirmado histologicamente em ambos os grupos. As variáveis foram analisadas de acordo com critérios aprovados biológica e estatisticamente. Foram efetuadas análises univariadas, bivariadas e multivariadas. Os casos e controles foram estratificados de acordo com o estado hormonal menopáusico (pré e pós-menopausa). Foi usado o odds ratio (OR) como método de associação com intervalos de confiança (IC) acima de 95%. RESULTADOS: Os fatores associados com o CM foram: nível socioeconômico alto (OR=2,77 IC 95% 1,77 -- 4,35); menarca prematura (OR=1,32 IC 95% 0,88 -- 2,00); idade acima de 31 anos quando da primeira gravidez (OR=5,49 IC 95% 21,16 -- 13,98) e um histórico familiar de CM (OR=4,76 IC 95% 2,10 -- 10,79). Por outro lado, um aumento na duração da amamentação foi um fator protetor (>; 25 meses OR=0,38 IC 95% 0,20 -- 0,77). CONCLUSÕES: Os resultados contribuíram para a identificação de fatores de risco para o CM descritos na literatura internacional na população de mulheres mexicanas. A amamentação parece exercer importante papel na proteção do CM. Em virtude das mudanças no estilo de vida das mulheres, as mulheres jovens tendem a diminuir seu período de amamentação.INTRODUCTION: In Mexico, breast cancer (BC) is one of the main causes of cancer deaths in women, with increasing incidence and mortality in recent years. Therefore, the aim of the study is identify possible risk factors related to BC. METHODS: An epidemiological study of hospital cases of BC and controls with cervical uterine cancer (CUCA) was carried out at eight third level concentration hospitals in Mexico City. The total of 353 incident cases of BC and 630 controls with CUCA were identified among women younger than 75 years who had been residents of the metropolitan area of Mexico City for at least one year. Diagnosis was confirmed histologically in both groups. Variables were analyzed according to biological and statistical plausibility criteria. Univariate, bivariate and multivariate analyses were carried out. Cases and controls were stratified according to the menopausal hormonal status (pre and post menopause). RESULTS: The factors associated with BC were: higher socioeconomic level (OR= 2.77; 95%CI = 1.77 - 4.35); early menarche (OR= 1.32; 95%CI= 0.88 - 2.00); old age at first pregnancy (>;31 years: OR= 5.49; 95%CI= 2.16 - 13.98) and a family history of BC (OR= 4.76; 95% CI= 2.10 - 10.79). In contrast, an increase in the duration of the breastfeeding period was a protective factor (>;25 months: OR= 0.38; 95%CI= 0.20 - 0.70). CONCLUSIONS: This study contributes to the identification of risk factors for BC described in the international literature, in the population of Mexican women. Breastfeeding appears to play an important role in protecting women from BC. Because of changes in women`s lifestyles, lactation is decreasing in Mexico, and young women tend not to breastfeed or to shorten the duration of lactation

Birth Weight, Body Silhouette Over the Life Course, and Incident Diabetes in 91,453 Middle-Aged Women From the French Etude Epidemiologique de Femmes de la Mutuelle Générale de l'Education Nationale (E3N) Cohort

International audienceOBJECTIVE: Obesity and increases in body weight in adults are considered to be among the most important risk factors for type 2 diabetes. Low birth weight is also associated with a higher diabetes incidence. We aimed to examine to what extent the evolution of body shape, from childhood to adulthood, is related to incident diabetes in late adulthood. RESEARCH DESIGN AND METHODS: Etude Epidemiologique de Femmes de la Mutuelle Générale de l'Education Nationale (E3N) is a cohort study of French women born in 1925-1950 and followed by questionnaire every 2 years. At baseline, in 1990, women were asked to report their current weight, height, and body silhouette at various ages. Birth weight was recorded in 2002. Cases of diabetes were self-reported or obtained by drug reimbursement record linkage and further validated. RESULTS: Of the 91,453 women who were nondiabetic at baseline, 2,534 developed diabetes over the 15 years of follow-up. Birth weight and body silhouette at 8 years, at menarche, and in young adulthood (20-25 years) were inversely associated with the risk of diabetes, independently of adult BMI during follow-up (all P(trend) < 0.001). In mid-adulthood (35-40 years), the association was reversed, with an increase in risk related to a larger body silhouette. An increase in body silhouette from childhood to mid-adulthood amplified the risk of diabetes. CONCLUSIONS: Low birth weight and thinness until young adulthood may increase the risk of diabetes, independently of adult BMI during follow-up. Young women who were lean children should be especially warned against weight gain

Dietary polyphenol intake and their major food sources in the Mexican Teachers' Cohort

Several descriptive studies on the intake of polyphenols, mostly flavonoids, have been published, especially in Europe and the USA, but insufficient data are still available in Latin-American countries, where different types of foods are consumed and different dietary habits are observed. The goal of this cross-sectional study was to estimate dietary intakes of polyphenols, including grand total, total per classes and subclasses and individual compounds, and to identify their main food sources in Mexican women. The Mexican Teachers' Cohort includes 115 315 female teachers, 25 years and older, from twelve states of Mexico, including urban and rural areas. Dietary data were collected in the period 2008-2011 using a validated FFQ, and individual polyphenol intake was estimated using food composition data from the Phenol-Explorer database. Median total polyphenol intake was the highest in Baja California (750 mg/d) and the lowest in Yucatan (536 mg/d). The main polyphenols consumed were phenolic acids (56.3-68.5 % total polyphenols), followed by flavonoids (28.8-40.9 %). Intake of other polyphenol subclasses (stilbenes, lignans and others) was insignificant. Coffee and fruits were the most important food sources of phenolic acids and flavonoids, respectively. Intake of a total of 287 different individual polyphenols could be estimated, of which forty-two were consumed in an amount 1 mg/d. The most largely consumed polyphenols were several caffeoylquinic acids (ranging from 20 and 460 mg/d), ferulic acid, hesperidin and proanthocyanidins. This study shows a large heterogeneity in intakes of individual polyphenols among Mexican women, but a moderate heterogeneity across Mexican states. Main food sources were also similar in the different states