Relationship between body mass index and residential segregation in large cities of Latin America.

BACKGROUND: Obesity is a global health problem, and its connection with social and environmental factors is well-established. Social factors, such as urban segregation, may impact obesity through various mechanisms, including food and physical activity environments, as well as social norms and networks. This multilevel study aims to examine the effect of socio-economic residential segregation of Latin American cities on the obesity of individuals within those cities. METHODS: We analyzed data from national surveys for a total of 59,340 individuals of 18-70 years of age, conducted in 156 cities across Brazil, Chile, Colombia, and Mexico between 2007 and 2013. We adjusted two-level linear mixed models for body mass index (BMI) stratified by sex and country, controlling for age, educational level and poverty. Separate models were built for dissimilarity and isolation segregation indices. RESULTS: The relationships between segregation indices and BMI were mostly not statistically significant, and in some cases, they were opposite to what was expected. The only significant relationships were observed in Colombian men, using the dissimilarity index (-7.5 [95% CI: -14.4, -0.5]) and in Colombian women, using the isolation index (-7.9 [95% CI: -14.1, -1.7]). CONCLUSIONS: While individual-level factors cannot fully explain differences among people in the same city, segregation indices may help. However, we found that in some cases, the relationship between BMI and segregation indices is opposite to what is expected based on prior literature. This should be considered in examining the phenomenon. Further research on obesogenic environments in segregated neighborhoods could provide valuable evidence.

Characterising variability and predictors of infant mortality in urban settings: findings from 286 Latin American cities.

BACKGROUND: Urbanisation in Latin America (LA) is heterogeneous and could have varying implications for infant mortality (IM). Identifying city factors related to IM can help design policies that promote infant health in cities. METHODS: We quantified variability in infant mortality rates (IMR) across cities and examined associations between urban characteristics and IMR in a cross-sectional design. We estimated IMR for the period 2014-2016 using vital registration for 286 cities above 100 000 people in eight countries. Using national censuses, we calculated population size, growth and three socioeconomic scores reflecting living conditions, service provision and population educational attainment. We included mass transit availability of bus rapid transit and subway. Using Poisson multilevel regression, we estimated the per cent difference in IMR for a one SD (1SD) difference in city-level predictors. RESULTS: Of the 286 cities, 130 had <250 000 inhabitants and 5 had >5 million. Overall IMR was 11.2 deaths/1000 live births. 57% of the total IMR variability across cities was within countries. Higher population growth, better living conditions, better service provision and mass transit availability were associated with 6.0% (95% CI -8.3 to 3.7%), 14.1% (95% CI -18.6 to -9.2), 11.4% (95% CI -16.1 to -6.4) and 6.6% (95% CI -9.2 to -3.9) lower IMR, respectively. Greater population size was associated with higher IMR. No association was observed for population-level educational attainment in the overall sample. CONCLUSION: Improving living conditions, service provision and public transportation in cities may have a positive impact on reducing IMR in LA cities.

Análisis inmunofenotípico de muestras normales de médula ósea: aplicaciones en el control de calidad en los laboratorios de citometría / Immunophenotypic analysis of normal cell samples from bone marrow: applications in quality control of cytometry laboratories / Análise imunofenotípica de amostras de medula óssea normal: aplicações no controle de qualidade em laboratórios de citometria

Objetivo. Describir un protocolo estandarizado mediante citometría de flujo para cuantificar en términos absolutos y relativos distintas subpoblaciones celulares de médula ósea normal y analizar la expresión de diferentes marcadores celulares específicos de linaje cuya reactividad está asociada a la diferenciación celular para ser usado como parte del control de calidad de rutina en los laboratorios de citometría. Materiales y métodos. El análisis inmunofenotípico de distintas subpoblaciones celulares se realizó en muestras de MO normal empleando un panel de anticuerpos monoclonales y policlonales útiles para la caracterización fenotípica de leucemias agudas en 4 fluorescencias distintas, con un protocolo que combina marcaje celular de antígenos de membrana y de citoplasma. El análisis de expresión se realizó en términos de intensidad media de fluorescencia. Para el cálculo de recuentos absolutos se adicionaron esferas fluorescentes de concentración conocida. Resultados. El panel de anticuerpos utilizado permitió la identificación y cuantificación de las distintas subpoblaciones leucocitarias normales de origen linfoide y mieloide incluyendo células precursoras CD34+, y poblaciones celulares más diferenciadas incluidas en las líneas granulocítica, monocítica y eritroide. Se establecieron los valores de referencia de las poblaciones celulares y los rangos de expresión de los diferentes marcadores celulares importantes como parte del control de calidad de rutina en los laboratorios de citometría. Conclusión. Los patrones inmunofenotípicos identificados y la determinación de los valores absolutos y relativos de referencia de las distintas poblaciones leucocitarias normales en MO podrán ser utilizados por los laboratorios de citometría como modelo para establecer parámetros de referencia en el análisis fenotípico de neoplasias hematológicas.

Objective. To describe a standardized flow cytometry protocol for the relative and absolute quantification of hematopoietic cell subpopulations from normal bone marrow, and to evaluate the expression of different lineage-specific cell markers with a reactivity associated to cell differentiation to be used as part of the routine quality control in cytometry laboratories. Materials and methods. The immunophenotypical analysis of different cell subpopulations was done with samples from normal bone marrow using a panel of monoclonal and polyclonal antibodies useful in the characterization of acute leukemias with four different fluorescences, by means of a protocol that combines cell labeling of membrane and cytoplasm antigens. Expression analysis was done in terms of mean fluorescence intensity (MFI). Fluorescent beads at a known concentration were added for calculating the absolute count of cells. Results. The antibody panel used allowed the identification and quantification of different normal leukocyte subpopulations of lymphatic and myeloid origin, including CD34+ stem cells and more differentiated cell populations in the granulocytic, monocytic, and erythroid cell lines. We established reference values for cell populations and cell marker expression ranges as part of routine quality control of cytometry laboratories. Conclusion. Immunophenotypic patterns identified as well as absolute and relative reference values for the different normal leukocyte populations from bone marrow can be used by cytometry laboratories as a basis for establishing reference parameters in phenotypic analyses of hematologic neoplasia.

Objetivo. Descrever um protocolo padronizado por citometria de fluxo para quantificar em termos absolutos e relativos diferentes subpopulações de células de medula óssea normal e analisar a expressão de diferentes marcadores celulares de linhagem específica, cuja reatividade é associada com a diferenciação celular para ser usado como parte do controle de qualidade de rotina nos laboratórios de citometria de fluxo. Materiais e métodos. A análise imunofenotípica das subpopulações de células foi realizada em amostras de MO normais utilizando um painel de anticorpos monoclonais e policlonais úteis para a caracterização fenotípica de leucemia aguda em quatro fluorescências, com um protocolo que combina rotulagem celular de antígeno de membrana celular e de citoplasma. A análise de expressão foi realizada em termos de intensidade média de fluorescência. Para calcular a recontagem absoluta foram adicionadas esferas fluorescentes de concentração conhecida. Resultados. O painel de anticorpos utilizado permitiu a identificação e quantificação das subpopulações de leucócitos normais de origem linfóide e mielóide incluindo as células precursoras CD34+, e populações de células mais diferenciadas incluídas nas linhas granulocítica, monocítica e eritróide. Foram estabelecidos os valores de referência das populações celulares e os intervalos de expressão dos diferentes marcadores celulares importantes como parte da rotina de controle de qualidade em laboratórios de citometria. Conclusão. Os padrões imunofenotípicos identificados e a determinação dos valores absolutos e relativos de referência das diferentes populações de leucócitos normais em MOM podem ser utilizados pelos laboratórios de citometria como um modelo para estabelecer parâmetros de referencia na análise fenotípica de neoplasias hematológicas.