Prospective measures of aging for Central and South America.

By conventional measures, it is often remarked that Central and South America is one of the fastest aging geographic regions in the world. In recent years, however, scholars have sought to problematize the orthodox measures and concepts employed in the aging literature. By not taking dynamic changes in life expectancy into account, measures which hold chronological age constant (e.g. defining a boundary to old age at 60 or 65) represent a very narrow view of population aging. Furthermore, such constant measures may misrepresent differences between territories when performing a comparative analysis. Prospective measures based on the number of years until death present an alternative approach which can adapt to dynamic changes in life expectancy and differences over time and space. The objective of this paper, then, is to apply the new 'prospective' measures of aging to the territories of Central and South America. We calculate prospective median age; an alternative old-age threshold based on the age at which remaining life expectancy is 15 years, and calculate prospective old-age dependency ratio for 1950-2100 using estimated and projected life tables from the latest iteration of the UN's World Population Prospects. These new measures present a very different view of aging in Central and South America. While there are significant differences across countries, the pace and scale of aging are considerably slower and diminished when compared to standard, orthodox measures based on fixed chronological ages. Applying these new measures can not only serve to present a more realistic view of aging which maps onto demographic reality but can also serve to reconceptualize and reframe the issue as something which is far more manageable (e.g. through institutional reform) than is often perceived to be.

Resilience of soil aggregation and exocellular enzymatic functions associated with arbuscular mycorrhizal fungal communities along a successional gradient in a tropical dry forest.

Arbuscular mycorrhizal (AM) fungi are well-known contributors to soil aggregation and nutrient cycling functions, but we still know little about their capacity to resist or recover from persistent disturbance. Rangeland management may deteriorate these functions by affecting the activity of soil biota, including AM fungi, among other consequences. If affected, some soil properties show recovery when management stops and natural regeneration is allowed. We conducted an experiment to evaluate if the functions related to soil aggregation and promotion of exocellular enzymatic activities associated with AM fungal communities had been affected by rangeland management and, if they had, whether they recovered with successional time when management stopped. AM fungal communities from ten sites with different successional ages in a tropical dry forest region were inoculated to the same host growing in pots divided by mesh into a plant compartment and an AM mycelium compartment. We examined soil stable aggregates fractions and enzymatic activities produced or promoted by AM fungi. Soil aggregation changed significantly only after the study had run for 3 years, was higher in the hyphosphere than in the root compartment, and showed a low but positive relation with the successional age of the communities. The activity of phosphatase, but not casein-protease and beta-glucosidase, increased with successional age. Therefore, soil aggregation and enzyme activities associated with AM fungal communities seemed resilient because casein-protease and beta-glucosidase were unchanged, and aggregation and phosphatase were reduced by rangeland management but recovered with successional time.

Breast metastasis from primary lung adenocarcinoma in a young woman: A case report and literature review.

BACKGROUND: Breast metastasis from extra mammary malignancies is rare. An incidence of 0.2%-1.3% has been reported in the literature, including that from different types of malignant neoplasms. CASE SUMMARY: We present a case of a 29-year-old nonsmoking woman with breast metastasis from lung adenocarcinoma. Computed tomography revealed atelectasis in the right middle lobe of the lung and ipsilateral pleural effusion. Additionally, on physical examination, a small mass was noted in her right breast. The patient underwent bronchoscopy, needle thoracentesis, and breast biopsy. Following cytology, histology and immunohistochemistry, primary lung adenocarcinoma with metastasis to the breast was diagnosed. Only 63 cases, including our patient, have been reported in the literature since 2000, and this is the second in a woman under 30 years of age. CONCLUSION: This atypical presentation may cause a significant diagnostic dilemma, but the contribution of immunohistochemistry is crucial to the accuracy of the final diagnosis.

Oligo-carrageenan kappa increases glucose, trehalose and TOR-P and subsequently stimulates the expression of genes involved in photosynthesis, and basal and secondary metabolisms in Eucalyptus globulus.

BACKGROUND: It has been previously shown that oligo-carrageenan (OC) kappa increases growth, photosynthesis and activities of enzymes involved in basal and secondary metabolisms in Eucalyptus globulus. However, it is not known whether OC kappa may induce the activation of TOR pathway and the increase in expression of genes encoding proteins involved in photosynthesis and enzymes of basal and secondary metabolisms. RESULTS: E. globulus trees were sprayed on leaves with water (control) or with OC kappa 1 mg mL- 1, once a week, four times in total, and cultivated for 17 additional weeks (21 weeks in total). Treated trees showed a higher level of net photosynthesis than controls, beginning at week 3, a higher height, beginning at week 9, and those differences remained until week 21. In addition, treated trees showed an increase in the level of glucose beginning at week 1, trehalose at weeks 1-3, and in TOR-P level at week 1-2. On the other hand, transcripts encoding proteins involved in photosynthesis, and enzymes involved in glucose accumulation, C, N and S assimilation, and synthesis of secondary metabolites began at weeks 3-4 and with additional peaks at weeks 5-6, 8-11,13-14 and 17-19. Thus, OC kappa induced initial increases in glucose, trehalose and TOR-P levels that were followed by oscillatory increases in the level of transcripts coding for proteins involved in photosynthesis, and in basal and secondary metabolisms suggesting that initial increases in glucose, trehalose and TOR-P may trigger activation of gene expression. CONCLUSIONS: The stimulation of growth induced by OC kappa in E. globulus trees is due, at least in part, to activation of TOR pathway and the increase in expression of genes encoding proteins involved in photosynthesis and enzymes of basal metabolism.

Sobreexpresión de C-MET en carcinoma de vesícula y del tracto biliar: prevalencia y correlación clínico-molecular / Overexpression of C-MET in gallbladder and biliary tract carcinoma: prevalence and clinical-molecular correlation

El objetivo fue determinar la sobreexpresión de c-MET en pacientes con cáncer biliar y analizar asociaciones con parámetros clínicos. Este es un estudio descriptivo, longitudinal, retrospectivo y prospectivo. Se determinó la sobreexpresión por inmunohistoquímica en 58 pacientes con resultados: positivo fuerte, positivo débil y negativo. Se construyeron curvas de supervivencia global con el método de KaplanMeier en todos los pacientes y en subgrupos según estadío, género, origen tumoral y grado de diferenciación histológica. La diferencia en supervivencia global entre subgrupos se analizó por el método log-rank. La asociación entre sobreexpresión y grado de diferenciación se estudió por el método chi cuadrado. Las pruebas estadísticas se realizaron a dos colas con un valor de p 0.05. Veintinueve muestras (50%) fueron negativas, 24 (41%) positivas débiles y 5 (9%) positivas fuertes. La mediana de supervivencia fue 18.2, 11.3 y 11.7 meses en pacientes con sobreexpresión negativa, positiva débil y positiva fuerte, respectivamente. Sin embargo, la diferencia en supervivencia global entre pacientes c-MET negativos y positivos (fuerte y débil) no alcanzó significancia estadística (p 0.068). En los subgrupos los resultados fueron similares. La sobreexpresión se asoció al grado de diferenciación (p 0.015), mostrando una relación inversa; y no se correlacionó con tasa de respuesta a la quimioterapia y tiempo a la progresión. La sobreexpresión de c-MET es frecuente en cáncer biliar, se asocia al grado de diferenciación tumoral y podría tener valor pronóstico. Si la vía c-MET es importante, los fármacos inhibidores tendrían impacto en la supervivencia global (AU)

The objective was to determine the overexpression of c-MET in patients with biliary cancer and to analyze associations with clinical parameters. This is a descriptive, longitudinal, retrospective and prospective study. Overexpression was obtained by immunohistochemistry in 58 patients, with the following results: strong positive, weak positive and negative. Overall survival curves were constructed using the Kaplan-Meier method in all patients and in subgroups according to stage, gender, tumor origin and grade of histological differentiation. The difference in overall survival between groups was analyzed by the log-rank test. The association between overexpression and grade of differentiation was studied using the chisquare method. Statistical tests were two-tailed with a p value 0.05. Twenty nine samples (50%) were negative, 24 (41%) weak positive and 5 (9%) strong positive. Median survival was 18.2, 11.3 and 11.7 months in patients with negative, weak positive and strong positive overexpression, respectively. However, the difference in overall survival between negative and positive (strong and weak together) c-MET patients did not reach statistical significance (p 0.068). In the subgroup analyses the results were similar. Overexpression correlated with tumor grade (p 0.015), showing an inverse association; and was not associated neither with chemotherapy response rate nor with time to progression. Overexpression of c-MET is common in biliary cancer, is associated with grade of tumor differentiation and could have prognostic value. If the c-MET pathway is important, the inhibitory drugs would have an impact on overall survival (AU)

Migrating focal seizures during infancy: a case report and pathologic study.

Migrating focal seizures in infancy are an unusual and often overlooked epilepsy syndrome, with onset before age 6 months, in which nearly continuous seizures involve multiple, independent areas of both hemispheres with an arrest of psychomotor development. We describe a patient with migrating focal seizures in infancy whose seizures began at age 45 days. The seizures were refractory to common antiepileptic drugs. At age 6 months, the infant received potassium bromide and became almost seizure-free. The infant developed severe neurologic impairment, with marked axial hypotonia and an absence of visual contact and head control. At age 8 months, the child suddenly died. Pathologic findings included multiple malformations of cortical development, polymicrogyria, and focal cortical dysplasia associated with hippocampal sclerosis.

Perfiles de síntesis y secreción de los péptidos natriuréticos durante la evolución de la hipertrofia cardíaca en ratas hipertensas DOCA-sal / Natriuretic Peptides Synthesis and Secretion Profiles during the Evolution of Cardiac Hypertrophy in DOCA-Salt Hypertensive Rats / Natriuretic Peptides Synthesis and Secretion Profiles during the Evolution of Cardiac Hypertrophy in DOCASalt Hypertensive Rats

Durante el desarrollo de la hipertensión arterial, las interacciones entre las sobrecargas de presión y de volumen conducen a diferentes patrones de hipertrofia cardíaca y a un aumento de los péptidos natriuréticos (PN). Los perfiles de síntesis y secreción de ANP y BNP se han investigado en modelos de hipertensión arterial; sin embargo, aún no se ha estudiado la evolución diferencial de estos perfiles durante períodos agudos y crónicos de la hipertrofia cardíaca producida por sobrecarga de volumen. Por este motivo estudiamos ratas Sprague- Dawley con el modelo DOCA-sal a las 2, 4, 6 y 12 semanas, correlacionando la evolución de dichos perfiles con la hipertrofia cardíaca y la hipertensión arterial. El grado de hipertrofia cardíaca se correlacionó positivamente con la expresión del ANP en el ventrículo izquierdo y con los niveles de ANP en plasma. La expresión del ANP aumentó a las 4 semanas de tratamiento, mientras que la de BNP se incrementó recién a las 6 semanas. Asimismo, el BNP plasmático se incrementó sólo en el grupo con 12 semanas de tratamiento, mientras que el ANP plasmático mostró un aumento a partir de las 2 semanas de tratamiento. Durante el desarrollo de la hipertrofia cardíaca producida en el modelo DOCA-sal, la síntesis y la secreción de los PN responden en forma diferencial, con incremento precoz del ANP. Además, el aumento de éste superó al de BNP en todos los grupos DOCA-sal, lo que permitiría considerar al ANP como un marcador más específico de la sobrecarga de volumen.

The interactions between pressure and volume overload that occur in hypertension lead to different patterns of cardiac hypertrophy and to increase in natriuretic peptides (NPs). The profiles of ANP and BNP synthesis and secretion have been investigated in models of hypertension; however, the different evolution of these profiles during the acute and chronic periods of pressure overload-induced cardiac hypertrophy is still unknown. For this reason, we studied DOCA-salt treated Sprague-Dawley rats at weeks 2, 4, 6 and 12 and correlated the evolution of these profiles with cardiac hypertrophy and hypertension. Cardiac hypertrophy had a positive correlation with ANP expression in the left ventricle and with ANP plasma levels. BNP expression increased after 4 weeks of treatment while ANP increased significantly after 6 weeks. In addition, BNP plasma levels increased only in the group treated for 12 weeks, while ANP plasma levels increased from week 2. NP secretion has a differential response in the early stages of the development of cardiac hypertrophy induced by the DOCA-salt model, with an early increase in ANP. As ANP levels were exceeded to those of BNP in all the DOCA-salt groups, ANP might be considered a more specific marker of volume overload.

[Demographic Dynamics and Educational Inequality in Mexico]. / La dinámica demográfica y la desigualdad educativa en México.

This paper seeks to explore the link between educational processes and Mexico's demographic dynamic. In the tradition of thought on population and development, it has been hypothesized that the population growth rate, family size and migration influence the accumulation of human capital among the school-age population. This study explores the link between the academic performance of youth between the age of 14 and 23 and the youth dependency ratio, teenage fertility and internal and international migration, using data aggregated at the municipal level for the year 2000. The analysis uses indicators on the educational supply at the municipal level based on the administrative statistics of the Public Education Secretariat (SEP).