myogenin: Human candidate gene and knockout mouse effect

The myogenin gene encodes an evolutionarily conserved basic helix-loop-helix transcription factor that regulates the expression of skeletal muscle-specific genes and its homozygous deletion results in mice who die of respiratory failure at birth. The histology of skeletal muscle in the myogenin null mice is reminiscent of that found in some severe congenital myopathy patients, many of whom also die of respiratory complications and provides the rationale that an aberrant human myogenin (myf4) coding region could be associated with some congenital myopathy conditions.^ With PCR, we found similarly sized amplimers for the three exons of the myogenin gene in 37 patient and 40 control samples. In contrast to the GeneBank sequence for human myogenin, we report several differences in flanking and coding regions plus an additional 659 and 498 bps in the first and second introns, respectively, in all patients and controls. We also find a novel (CA)-dinucleotide repeat in the second intron. No causative mutations were detected in the myogenin coding regions of genomic DNA from patients with severe congenital myopathy.^ Severe congenital myopathies in humans are often associated with respiratory complications and pulmonary hypoplasia. We have employed the myogenin null mouse, which lacks normal development of skeletal muscle fibers as a genetically defined severe congenital myopathy mouse model to evaluate the effect of absent fetal breathing movement on pulmonary development.^ Significant differences are observed at embryonic days E14, E17 and E20 of lung:body weight, total DNA and histologically, suggesting that the myogenin null lungs are hypoplastic. RT-PCR, in-situ immunofluorescence and EM reveal pneumocyte type II differentiation in both null and wild lungs as early as E14. However, at E14, myogenin null lungs have decreased BrdU incorporation while E17 through term, augmented cell death is detected in the myogenin null lungs, not seen in wild littermates. Absent mechanical forces appear to impair normal growth, but not maturation, of the developing lungs in myogenin null mouse.^ These investigations provide the basis for delineating the DNA sequence of the myogenin gene and and highlight the importance of skeletal muscle development in utero for normal lung organogenesis. My observation of no mutations within the coding regions of the human myogenin gene in DNA from patients with severe congenital myopathy do not support any association with this condition. ^

A longitudinal comparison of cardiovascular disease risk factors among children and adolescents in the U.S. and Japan: Project HeartBeat!

Blood cholesterol and blood pressure development in childhood and adolescence have important impact on the future adult level of cholesterol and blood pressure, and on increased risk of cardiovascular diseases. The U.S. has higher mortality rates of coronary heart diseases than Japan. A longitudinal comparison in children of risk factor development in the two countries provides more understanding about the causes of cardiovascular disease and its prevention. Such comparisons have not been reported in the past. ^ In Project HeartBeat!, 506 non-Hispanic white, 136 black and 369 Japanese children participated in the study in the U.S. and Japan from 1991 to 1995. A synthetic cohort of ages 8 to 18 years was composed by three cohorts with starting ages at 8, 11, and 14. A multilevel regression model was used for data analysis. ^ The study revealed that the Japanese children had significantly higher slopes of mean total cholesterol (TC) and high density lipoprotein (HDL) cholesterol levels than the U.S. children after adjusting for age and sex. The mean TC level of Japanese children was not significantly different from white and black children. The mean HDL level of Japanese children was significantly higher than white and black children after adjusting for age and sex. The ratio of HDL/TC in Japanese children was significantly higher than in U.S. whites, but not significantly different from the black children. The Japanese group had significantly lower mean diastolic blood pressure phase IV (DBP4) and phase V (DBP5) than the two U.S. groups. The Japanese group also showed significantly higher slopes in systolic blood pressure, DBP5 and DBP4 during the study period than both U.S. groups. The differences were independent from height and body mass index. ^ The study provided the first longitudinal comparison of blood cholesterol and blood pressure between the U.S. and Japanese children and adolescents. It revealed the dynamic process of these factors in the three ethnic groups. ^

Local environmental knowledge: a key input for the sustainable development of Andean mountain communities

Local knowledge is crucial to both human development and environmental conservation. This is especially the case in mountain regions, where a combination of remoteness, harsh climatic conditions, rich cultural heritage, and high biological diversity has led to the development of complex local environmental knowledge systems. In the Andes for instance, rural populations mainly rely on their own environmental knowledge to ensure their food security and health. Recent studies conducted within Quechua communities in Peru and Bolivia showed that this knowledge was both persistent and dynamic, and that it responded to socio-economic and environmental changes through cultural resistance and adaptation. As this paper argues, combining local knowledge and so-called scientific knowledge – especially in development projects – can lead to innovative solutions to the socio-environmental challenges facing mountain communities in our globalized world. Based on experiences from the Andes, this paper will provide concrete recommendations to policymakers and practitioners for integrating local knowledge into development and natural resource management initiatives.

Towards a spatial understanding of trade-offs in sustainable development: A meso-scale analysis of the nexus between land use, poverty, and environment in the Lao PDR

In land systems, equitably managing trade-offs between planetary boundaries and human development needs represents a grand challenge in sustainability oriented initiatives. Informing such initiatives requires knowledge about the nexus between land use, poverty, and environment. This paper presents results from Lao PDR, where we combined nationwide spatial data on land use types and the environmental state of landscapes with village-level poverty indicators. Our analysis reveals two general but contrasting trends. First, landscapes with paddy or permanent agriculture allow a greater number of people to live in less poverty but come at the price of a decrease in natural vegetation cover. Second, people practising extensive swidden agriculture and living in intact environments are often better off than people in degraded paddy or permanent agriculture. As poverty rates within different landscape types vary more than between landscape types, we cannot stipulate a land use–poverty–environment nexus. However, the distinct spatial patterns or configurations of these rates point to other important factors at play. Drawing on ethnicity as a proximate factor for endogenous development potentials and accessibility as a proximate factor for external influences, we further explore these linkages. Ethnicity is strongly related to poverty in all land use types almost independently of accessibility, implying that social distance outweighs geographic or physical distance. In turn, accessibility, almost a precondition for poverty alleviation, is mainly beneficial to ethnic majority groups and people living in paddy or permanent agriculture. These groups are able to translate improved accessibility into poverty alleviation. Our results show that the concurrence of external influences with local—highly contextual—development potentials is key to shaping outcomes of the land use–poverty–environment nexus. By addressing such leverage points, these findings help guide more effective development interventions. At the same time, they point to the need in land change science to better integrate the understanding of place-based land indicators with process-based drivers of land use change.

Body fat distribution and serum lipids in children and adolescents

Previous studies of normal children have linked body fat but not body fat distribution (BFD), to higher blood pressures, lipids, and insulin resistance (Berenson et al., 1988) BFD is a well-established risk factor for cardiovascular disease in adults (Björntorp, 1988). This study investigates the relation of BFD and serum lipids at baseline in children from Project HeartBeat!, a study of the growth and development of cardiovascular risk factors in 678 children in three cohorts measured initially at ages 8, 11, and 14 years. Initially, two of four indices of BFD were significantly related to the lipids: ratio of upper to lower body skinfolds (ln US:LS) and conicity (C Index). A factor analysis reduced the information in the serum lipids to two vectors: (1) total cholesterol + LDL-cholesterol and (2) HDL-cholesterol − triglycerides, which together accounted for 85% of the lipid variation. Using each serum lipid and vector as separate dependent variables, linear and quadratic regression models were constructed to examine the predictive ability of the two BFD variables, controlling for total body fat, gender, ethnicity (Black, non-Black) and maturation. Linear models provided an acceptable fit. Percent body fat (%BF) was a significant predictor in each and every lipid model, independent of age, maturation, or ethnicity (p ≤ 0.05). No BFD variable entered the equation for total or LDL-cholesterol, although there was a significant maturity by BFD interaction for LDL (ln US:LS was a significant predictor in more mature individuals). Both %BF and BFD (by way of Conicity) were significant predictors of HDL-cholesterol and triglycerides (p ≤ 0.01). All models were statistically significant at a high level (p ≤ 0.01), but adjusted R 2's for all models were low (0.05–0.15). Body fat distribution is a significant predictor of lipids in normal children, but secondarily to %BF, and for LDL-cholesterol in particular, the relation is dependent on maturity status. ^

Tracking of plasma lipids and lipoproteins, within-person and year-to-year variability in plasma cholesterol levels among participants from age 8 to 18 in Project HeartBeat!

Coronary heart disease remains the leading cause of death in the United States and increased blood cholesterol level has been found to be a major risk factor with roots in childhood. Tracking of cholesterol, i.e., the tendency to maintain a particular cholesterol level relative to the rest of the population, and variability in blood lipid levels with increase in age have implications for cholesterol screening and assessment of lipid levels in children for possible prevention of further rise to prevent adulthood heart disease. In this study the pattern of change in plasma lipids, over time, and their tracking were investigated. Also, within-person variance and retest reliability defined as the square root of within-person variance for plasma total cholesterol, HDL-cholesterol, LDL-cholesterol, and triglycerides and their relation to age, sex and body mass index among participants from age 8 to 18 years were investigated. ^ In Project HeartBeat!, 678 healthy children aged 8, 11 and 14 years at baseline were enrolled and examined at 4-monthly intervals for up to 4 years. We examined the relationship between repeated observations by Pearson's correlations. Age- and sex-specific quintiles were calculated and the probability of participants to remain in the uppermost quintile of their respective distribution was evaluated with life table methods. Plasma total cholesterol, HDL-C and LDL-C at baseline were strongly and significantly correlated with measurements at subsequent visits across the sex and age groups. Plasma triglyceride at baseline was also significantly correlated with subsequent measurements but less strongly than was the case for other plasma lipids. The probability to remain in the upper quintile was also high (60 to 70%) for plasma total cholesterol, HDL-C and LDL-C. ^ We used a mixed longitudinal, or synthetic cohort design with continuous observations from age 8 to 18 years to estimate within person variance of plasma total cholesterol, HDL-C, LDL-C and triglycerides. A total of 5809 measurements were available for both cholesterol and triglycerides. A multilevel linear model was used. Within-person variance among repeated measures over up to four years of follow-up was estimated for total cholesterol, HDL-C, LDL-C and triglycerides separately. The relationship of within-person and inter-individual variance with age, sex, and body mass index was evaluated. Likelihood ratio tests were conducted by calculating the deviation of −2log (likelihood) within the basic model and alternative models. The square root of within-person variance provided the retest reliability (within person standard deviation) for plasma total cholesterol, HDL-C, LDL-C and triglycerides. We found 13.6 percent retest reliability for plasma cholesterol, 6.1 percent for HDL-cholesterol, 11.9 percent for LDL-cholesterol and 32.4 percent for triglycerides. Retest reliability of plasma lipids was significantly related with age and body mass index. It increased with increase in body mass index and age. These findings have implications for screening guidelines, as participants in the uppermost quintile tended to maintain their status in each of the age groups during a four-year follow-up. The magnitude of within-person variability of plasma lipids influences the ability to classify children into risk categories recommended by the National Cholesterol Education Program. ^

Total cholesterol and anthropometric measurements distributions in a cross-sectional study of school children

Cross-sectional age and sex specific distributions of serum total cholesterol were described for 1091 children age 6-18 years, in The Woodlands, Texas. Associations of serum total cholesterol with five anthropometric measurements (weight, height, body mass index, arm circumference, and triceps skinfold thickness) were examined by correlation and regression analyses. Examination of serum total cholesterol distributions showed lower levels in boys than in girls for most of the age groups studied. Mean levels of total cholesterol peaked at age 9 for boys and 8 for girls. Serum total cholesterol leveled off until age 14 for boys and 11 for girls, and then dropped through age 18 for both boys and girls. These results support the hypothesis that serum total cholesterol concentration drops at pre-adolescence.^ Age adjusted correlations were observed between serum total cholesterol and triceps skinfold thickness for both boys and girls. This association was stronger in boys. Triceps skinfold thickness and arm circumference were consistently the strongest correlates for serum total cholesterol in boys. Weight and arm circumference were consistently the strongest correlates for serum total cholesterol in girls. ^

Growth and development of body fat distribution from skinfold measurements: Longitudinal principal components

Longitudinal principal components analyses on a combination of four subcutaneous skinfolds (biceps, triceps, subscapular and suprailiac) were performed using data from the London Longitudinal Growth Study. The main objectives were to discover at what age during growth sex differences in body fat distribution occur and to see if there is continuity in body fatness and body fat distribution from childhood into the adult status (18 years). The analyses were done for four age sectors (3mon-3yrs, 3yrs-8yrs, 8yrs-18yrs and 3yrs-18yrs). Longitudinal principal component one (LPC1) for each age interval in both sexes represents the population mean fat curve. Component two (LPC2) is a velocity of fatness component. Component three (LPC3) in the 3mon-3yrs age sector represents infant fat wave in both sexes. In the next two age sectors component three in males represents peaks and shifts in fat growth (change in velocity), while in females it represents body fat distribution. Component four (LPC4) in the same two age sectors is a reversal in the sexes of the patterns seen for component three, i.e., in males it is body fat distribution and in females velocity shifts. Components five and above represent more complicated patterns of change (multiple increases and decreases across the age interval). In both sexes there is strong tracking in fatness from middle childhood to adolescence. In males only there is also a low to moderate tracking of infant fat with middle to late childhood fat. These data are strongly supported in the literature. Several factors are known to predict adult fatness among the most important being previous levels of fatness (at earlier ages) and the age at rebound. In addition we found that the velocity of fat change in middle childhood was highly predictive of later fatness (r $\approx -$0.7), even more so than age at rebound (r $\approx -$0.5). In contrast to fatness (LPC1), body fat distribution (LPC3-LPC4) did not track well even though significant components of body fat distribution occur at each age. Tracking of body fat distribution was higher in females than males. Sex differences in body fat distribution are non existent. Some sex differences are evident with the peripheral-to-central ratios after age 14 years. ^

Un desafío pendiente para el próximo quinquenio : Los objetivos de desarrollo del milenio

En el año 2000, los gobiernos de 189 países se comprometieron a alcanzar dieciocho metas para combatir la desigualdad y mejorar el desarrollo humano en el mundo a través del cumplimiento de los denominados Objetivos de Desarrollo del Milenio (ODM) de la Organización de las Naciones Unidas (ONU), todo ello con un horizonte para el año 2015. Los ODM deben ser monitoreados por los institutos de estadística existentes en la mayoría de los países que calculan indicadores económicos. En la Argentina, el Instituto Nacional de Estadística y Censos tiene una larga experiencia en la creación y cálculo de índices, específicamente, del índice de Precios al Consumidor el cual ha sido considerado como el mejor índice de precios de toda América Latina. Sin embargo, desde el año 2007 se ha implementado una nueva metodología para su cálculo. En esta comunicación se presentan resultados de trabajos realizados desde diferentes puntos de vista que aportan los métodos exploratorios y confirmatorios tendientes a conocer la situación de pobreza e indigencia y la distribución de los ingresos de los habitantes del Aglomerado Gran Rosario. Los análisis exploratorios y confirmatorios aplicados presentan incuestionables resultados que reflejan la coherencia de las conclusiones a que se ha arribado. Los datos primarios de calidad utilizados permitieron plasmar análisis dinámicos con la información homogénea disponible. Finalmente y a la luz de estas circunstancias, ¿se podrá saber fehacientemente si se alcanzarán los Objetivos de Desarrollo del Milenio en el año 2015?

Los profesores principiantes enseñan historia

El objetivo de este trabajo es conocer cómo se incorporan a la labor docente, y en ese contexto cómo enseñan historia, los profesores noveles egresados de los profesorados en historia de la UNGS (Universidad Nacional de General Sarmiento) y del ISFD no 42 (Instituto Superior de Formación Docente). Son considerados docentes noveles o principiantes aquellos profesores que se encuentran en los primeros tres años del ejercicio de la profesión. La información aquí presentada fue recogida a través de una investigación de tipo cualitativa realizada entre el IDH (Instituto del Desarrollo Humano), perteneciente a la Universidad Nacional de General Sarmiento y el Instituto Superior de Formación Docente no 42 de San Miguel, provincia de Buenos Aires Este proyecto, realizado entre los años 2008 y 2010, fue dirigido por la doctora Gabriela Diker, quien en ese momento se desempeñaba como coordinadora del área de formación del IDH de la UNGS. Preguntas como: ¿cuáles son las dificultades que deben afrontar los profesores principiantes?, ¿qué respuestas elaboran ante dichas dificultades?, ¿cómo desarrollan el proceso de enseñanza de la historia?, ¿qué recursos y materiales utilizan para ello?, ¿cómo influyen las trayectorias de formación docente sobre las prácticas que desarrollan los profesores principiantes? servirán de guía a fin de poder indagar la trayectoria docente en este período inicial para luego caracterizarlo, analizarlo y finalmente volver a evaluar los alcances y límites de la información brindada por la investigación. Un punto interesante será comparar los trayectos formativos por los que atravesaron los graduados de ambas instituciones, teniendo en cuenta que un grupo de graduados se formó en una institución universitaria y el otro colectivo de profesores proviene de una institución terciaria. El objetivo es identificar si las instituciones formadoras de base ejercen alguna influencia que permita diferenciar comparativamente las prácticas de un grupo respecto del otro

Un desafío pendiente para el próximo quinquenio : Los objetivos de desarrollo del milenio

En el año 2000, los gobiernos de 189 países se comprometieron a alcanzar dieciocho metas para combatir la desigualdad y mejorar el desarrollo humano en el mundo a través del cumplimiento de los denominados Objetivos de Desarrollo del Milenio (ODM) de la Organización de las Naciones Unidas (ONU), todo ello con un horizonte para el año 2015. Los ODM deben ser monitoreados por los institutos de estadística existentes en la mayoría de los países que calculan indicadores económicos. En la Argentina, el Instituto Nacional de Estadística y Censos tiene una larga experiencia en la creación y cálculo de índices, específicamente, del índice de Precios al Consumidor el cual ha sido considerado como el mejor índice de precios de toda América Latina. Sin embargo, desde el año 2007 se ha implementado una nueva metodología para su cálculo. En esta comunicación se presentan resultados de trabajos realizados desde diferentes puntos de vista que aportan los métodos exploratorios y confirmatorios tendientes a conocer la situación de pobreza e indigencia y la distribución de los ingresos de los habitantes del Aglomerado Gran Rosario. Los análisis exploratorios y confirmatorios aplicados presentan incuestionables resultados que reflejan la coherencia de las conclusiones a que se ha arribado. Los datos primarios de calidad utilizados permitieron plasmar análisis dinámicos con la información homogénea disponible. Finalmente y a la luz de estas circunstancias, ¿se podrá saber fehacientemente si se alcanzarán los Objetivos de Desarrollo del Milenio en el año 2015?

Los profesores principiantes enseñan historia

El objetivo de este trabajo es conocer cómo se incorporan a la labor docente, y en ese contexto cómo enseñan historia, los profesores noveles egresados de los profesorados en historia de la UNGS (Universidad Nacional de General Sarmiento) y del ISFD no 42 (Instituto Superior de Formación Docente). Son considerados docentes noveles o principiantes aquellos profesores que se encuentran en los primeros tres años del ejercicio de la profesión. La información aquí presentada fue recogida a través de una investigación de tipo cualitativa realizada entre el IDH (Instituto del Desarrollo Humano), perteneciente a la Universidad Nacional de General Sarmiento y el Instituto Superior de Formación Docente no 42 de San Miguel, provincia de Buenos Aires Este proyecto, realizado entre los años 2008 y 2010, fue dirigido por la doctora Gabriela Diker, quien en ese momento se desempeñaba como coordinadora del área de formación del IDH de la UNGS. Preguntas como: ¿cuáles son las dificultades que deben afrontar los profesores principiantes?, ¿qué respuestas elaboran ante dichas dificultades?, ¿cómo desarrollan el proceso de enseñanza de la historia?, ¿qué recursos y materiales utilizan para ello?, ¿cómo influyen las trayectorias de formación docente sobre las prácticas que desarrollan los profesores principiantes? servirán de guía a fin de poder indagar la trayectoria docente en este período inicial para luego caracterizarlo, analizarlo y finalmente volver a evaluar los alcances y límites de la información brindada por la investigación. Un punto interesante será comparar los trayectos formativos por los que atravesaron los graduados de ambas instituciones, teniendo en cuenta que un grupo de graduados se formó en una institución universitaria y el otro colectivo de profesores proviene de una institución terciaria. El objetivo es identificar si las instituciones formadoras de base ejercen alguna influencia que permita diferenciar comparativamente las prácticas de un grupo respecto del otro

Un desafío pendiente para el próximo quinquenio : Los objetivos de desarrollo del milenio

En el año 2000, los gobiernos de 189 países se comprometieron a alcanzar dieciocho metas para combatir la desigualdad y mejorar el desarrollo humano en el mundo a través del cumplimiento de los denominados Objetivos de Desarrollo del Milenio (ODM) de la Organización de las Naciones Unidas (ONU), todo ello con un horizonte para el año 2015. Los ODM deben ser monitoreados por los institutos de estadística existentes en la mayoría de los países que calculan indicadores económicos. En la Argentina, el Instituto Nacional de Estadística y Censos tiene una larga experiencia en la creación y cálculo de índices, específicamente, del índice de Precios al Consumidor el cual ha sido considerado como el mejor índice de precios de toda América Latina. Sin embargo, desde el año 2007 se ha implementado una nueva metodología para su cálculo. En esta comunicación se presentan resultados de trabajos realizados desde diferentes puntos de vista que aportan los métodos exploratorios y confirmatorios tendientes a conocer la situación de pobreza e indigencia y la distribución de los ingresos de los habitantes del Aglomerado Gran Rosario. Los análisis exploratorios y confirmatorios aplicados presentan incuestionables resultados que reflejan la coherencia de las conclusiones a que se ha arribado. Los datos primarios de calidad utilizados permitieron plasmar análisis dinámicos con la información homogénea disponible. Finalmente y a la luz de estas circunstancias, ¿se podrá saber fehacientemente si se alcanzarán los Objetivos de Desarrollo del Milenio en el año 2015?

Los profesores principiantes enseñan historia

El objetivo de este trabajo es conocer cómo se incorporan a la labor docente, y en ese contexto cómo enseñan historia, los profesores noveles egresados de los profesorados en historia de la UNGS (Universidad Nacional de General Sarmiento) y del ISFD no 42 (Instituto Superior de Formación Docente). Son considerados docentes noveles o principiantes aquellos profesores que se encuentran en los primeros tres años del ejercicio de la profesión. La información aquí presentada fue recogida a través de una investigación de tipo cualitativa realizada entre el IDH (Instituto del Desarrollo Humano), perteneciente a la Universidad Nacional de General Sarmiento y el Instituto Superior de Formación Docente no 42 de San Miguel, provincia de Buenos Aires Este proyecto, realizado entre los años 2008 y 2010, fue dirigido por la doctora Gabriela Diker, quien en ese momento se desempeñaba como coordinadora del área de formación del IDH de la UNGS. Preguntas como: ¿cuáles son las dificultades que deben afrontar los profesores principiantes?, ¿qué respuestas elaboran ante dichas dificultades?, ¿cómo desarrollan el proceso de enseñanza de la historia?, ¿qué recursos y materiales utilizan para ello?, ¿cómo influyen las trayectorias de formación docente sobre las prácticas que desarrollan los profesores principiantes? servirán de guía a fin de poder indagar la trayectoria docente en este período inicial para luego caracterizarlo, analizarlo y finalmente volver a evaluar los alcances y límites de la información brindada por la investigación. Un punto interesante será comparar los trayectos formativos por los que atravesaron los graduados de ambas instituciones, teniendo en cuenta que un grupo de graduados se formó en una institución universitaria y el otro colectivo de profesores proviene de una institución terciaria. El objetivo es identificar si las instituciones formadoras de base ejercen alguna influencia que permita diferenciar comparativamente las prácticas de un grupo respecto del otro