Pretreatment CD4 Cell Slope and Progression to AIDS or Death in HIV-Infected Patients Initiating Antiretroviral Therapy—The CASCADE Collaboration: A Collaboration of 23 Cohort Studies

Analyzing data from several thousand cohort study participants, Marcel Wolbers and colleagues find that the rate of CD4 T cell decline is not useful in deciding when to start HIV treatment

Interbank borrowing and lending between financially constrained banks

Some stylized facts about transactions among banks are not easily reconciled with coinsurance of short-term liquidity risks. In our model, interbank markets play a different role. We argue that lending to another bank can reduce a bank’s overall portfolio risk through diversification. If insolvency is costly, this diversification improves the interbank lender's funding liquidity, boosting credit supply to nonbanks. However, diversification comes at an endogenous cost that depends on bank-specific factors of interbank borrower and lender. The model provides a framework for understanding the importance of interbank lending for aggregate credit supply and the stability of banking systems. The model’s predictions are consistent with evidence documented in the literature that other theories cannot consistently explain

Impact of growth and uptake patterns of arbuscular mycorrhizal fungi on plant phosphorus uptake—a modelling study

In this paper we present a mathematical model for estimating external mycelium growth of arbuscular mycorrhizal fungi and its effect on root uptake of phosphate (P). The model describes P transport in soil and P uptake by both root and fungi on the single root scale. We investigate differences in soil P depletion and overall P influx into a mycorrhizal root by assuming that different spatial regions of mycelia are active in P uptake.When all external hyphae contribute to P uptake, overall uptake is dominated by the fungus and the most effective growth pattern appears to be the one using a high level of anastomosis. The same is true when only the proportion of external hyphae assumed to be active contributes to uptake. When uptake is restricted to the tips, hyphal contribution to overall P uptake is less dominant; the most effective growth pattern appears to be the one characterised by nonlinear branching where branching stops at a given maximal hyphal tip density. Comparison to measured P depletion in the literature suggests that the scenario where active hyphae are contributing to P uptake is likely to fit the data best. These quantitative predictions promote our understanding of the mycorrhizal symbiosis and its role in plant P nutrition

Estudio descriptivo del uso de drogas en adolescentes de educación media superior de la ciudad de Monterrey, Nueva León, México Estudo descritivo do uso de drogas em adolescentes de educação média supeiror da cidade de monterrey, Nova Leon, México Descriptive study of drugs use among adolescents in higher middle education in Monterrey, Nueva León, Mexico

Se buscó establecer el perfil de consumo de drogas lícitas e ilícitas, patrones de consumo y estrategias de afrontamiento y resistencia al alcohol, tabaco y otras drogas en adolescentes de educación media superior. El estudio se sustentó en los conceptos de autores especializados en el tema considerándose las características conductuales, psicológicas y normativas de la persona. La muestra no probabilística consistió de 325 jóvenes. Los resultados indicaron que 67%, 65% y 7% de los adolescentes aceptaron haber usado alcohol, tabaco y marihuana alguna vez en su vida respectivamente y en el último mes el 33%, 38% y 3% esas mismas substancias, 65% consideran que la mayoría de sus compañeros han hecho uso; 56% tuvieron que rechazar una vez el ofrecimiento de alcohol, 64% tabaco y 51% marihuana, en el último mes con base en esos hallazgos. Se recomienda implementar un programa de prevención orientado a apoyar los recursos del adolescente para resistir las presiones para el consumo.<br>Buscou-se estabelecer o perfil de consumo de drogas lícitas e ilícitas, padrões de consumo e estratégias de enfrentamento e resistência ao álcool, tabaco e outras drogas em adolescentes de educação média superior. O estudo fundamentou-se nos conceitos de autores especializados no tema, considerando-se as características comportamentais, psicológicas normativas da pessoa. A amostra, não probabilística, consistiu de 325 jovens. Os resultados indicaram que 67%, 65% e 7% dos adolescentes aceitaram haver usado álcool, tabaco e maconha alguma vez na vida respectivamente e no último mês, 33%, 38% e 3% essas mesmas substâncias; 65% consideram que a maioria de seus companheiros fez uso; 56% tiveram que recusar uma vez a oferta de álcool, 64% tabaco e 51% maconha, no último mês. Com base nesses achados recomenda-se a implementação de um programa de prevenção orientado a apoiar os aportes dos adolescentes para resistir à pressão para o consumo.<br>We aimed to establish the consumption profile of licit and illicit drugs, consumption patterns and strategies for coping and resisting alcohol, tobacco and other drugs among adolescents in higher middle education. This study was based on concepts developed by specialized authors and considered the subject's behavioral, psychological and normative characteristics. The non-probabilistic sample consisted of 325 adolescents. Results indicated that 67%, 65% and 7% of the adolescents, respectively, accepted they had already used alcohol, tobacco and marihuana at some time in their life and that 33%, 38% and 3%, respectively, had used these same substances over the last month; 65% consider most of their colleagues have used these substances; 56% had to reject an offer to consume alcohol, 64% tobacco and 51% marihuana over the last month. On the basis of these findings, we recommend the implementation of a prevention program aimed at supporting the adolescent's resources to resist pressure towards consumption

Urinary erythropoietin concentrations after early short-term infusion of high-dose recombinant epo for neuroprotection in preterm neonates

BACKGROUND: High-dose recombinant human erythropoietin (rEpo) has first been administered in clinical trials for neuroprotection in very preterm neonates at high risk of brain injury and in (near-) term neonates with hypoxic-ischemic encephalopathy. However, recent trials in adults raised concerns about the safety of high-dose rEpo for neuro- and cardioprotection. OBJECTIVES: To evaluate the putative accumulation or renal leakage of Epo as a function of developmental stage after repetitive early short-term infusion of high-dose rEpo (3 × 3,000 U/kg within 42 h after birth; NCT00413946) for neuroprotection in very preterm infants. METHODS: Epo concentrations were measured using the ELISA technique in the first two consecutive urine specimens after each rEpo infusion. RESULTS: Renal Epo excretion was significantly higher in preterm infants with gestational ages <29 weeks than in more mature infants and reached up to 23% of the administered rEpo within 8 h after each infusion. The urinary Epo concentration did not increase after three repetitive infusions of high-dose rEpo. The ratio of urinary Epo to total protein concentrations was the same in infants with gestational ages <29 weeks and in those with gestational ages ≥29 weeks. CONCLUSIONS: Our data suggest that the higher renal Epo excretion in more immature infants may be attributed to a higher glomerular filtration leakage due to the lower maturation of the kidneys and argue against saturation kinetics after multiple doses of 3,000 U/kg rEpo. This information should be considered in future trials on the use of rEpo for neuroprotection in neonates