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Selecting a trait linked to metabolic pathways that enhance resistance and tolerance to biotic and abiotic stresses may be an excellent alternative. A practical approach to increase the productivity of annual crops is to maximize the photosynthetic efficiency in plant breeding. The purpose of this study was to discriminate common bean genotypes during physiological senescence with regard to the stay-green trait and analyze its effects on other traits of agronomic interest. Ten common bean genotypes were analyzed in a randomized complete block design with three replications. The stay-green trait was assessed by visual scores at harvest. The chlorophyll a content, chlorophyll b and green pod color were also evaluated during senescence (75, 80, 85, 90, and 95 days after sowing). Pod maturation of all evaluated genotypes was standard when they reached 95 days after sowing. The stay - green feature was detected only in the genotypes BRS Expedito, FT - Tarumã and BAF071. Genetic variability in the mechanisms related to late senescence is indicated by: i) a high initial chlorophyll a content; and ii) reduced chlorophyll degradation throughout senescence. Plants with stay-green properties were significantly correlated with a lower incidence and severity of plant pathology, greater stem diameter, and higher grain yield.

Selecionar uma característica relacionada às vias metabólicas responsáveis pelo aumento da resistência e/ou tolerância a estresses bióticos e abióticos pode ser uma excelente alternativa no melhoramento de plantas. Uma abordagem prática para aumentar a produtividade das culturas anuais é maximizar a eficiência fotossintética. O objetivo do trabalho foi discriminar genótipos de feijão durante a senescência fisiológica quanto ao caráter stay-green e correlacionar os efeitos sobre outros caracteres de interesse agronômico. Foram avaliados dez genótipos de feijão submetidos ao delineamento de blocos casualizados com três repetições. O caráter stay-green foi mensurado por escores de notas visuais na colheita. Também foram avaliados o teor de clorofila a, teor de clorofila b e coloração verde do legume no decorrer da senescência (75, 80, 85, 90, 95 dias após semeadura). A maturação dos legumes foi padrão para todos osgenótipos avaliados. Os genótipos BRS Expedito, FT - Tarumã e BAF071 apresentaram stay-green, diferentemente dos demais. A variabilidade genética nos mecanismos relacionados a senescência tardia, são detectadas pela: i) elevado teor de clorofila a inicial; e ii) reduzida degradação de clorofila ao longo da senescência. As plantas com stay-green apresentaram correlações significativas com menor incidência e severidade de fitopatologias, maior diâmetro do caule e rendimento de grãos.

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BACKGROUND: Abnormal activity of two enzymes relevant to neurodevelopment, namely nuclear-distribution element-like 1 (Ndel1) and angiotensin I-converting enzyme (ACE), was reported in individuals with schizophrenia; to our knowledge, these oligopeptidases were never measured in bipolar disorder (BD). AIMS: Evaluate the enzyme activity of Ndel1 and ACE in euthymic individuals with BD type 1 which was compare to healthy control (HC) group. METHODS: Ndel1 and ACE activities were assessed in the serum of individuals with BD type 1 according to DSM-IV criteria (n = 70) and a HC group (n = 34). The possible differences between BD type 1 and HC groups were evaluated using Analysis of Covariance (ANCOVA), and the results were adjusted for age, gender and body mass index. RESULTS: We observed a positive correlation between Ndel1 activity and the total YMRS score in BD group (p = 0.030) and a positive correlation between ACE activity and Ham-D score (p = 0.047). ANCOVA analysis showed lower Ndel1 activity in BDs compared to HCs. Interestingly, we did not observe between-groups differences in ACE activity, despite the recognized correlation of ACE activity levels with cognitive functions, also described to be worsened in psychiatric patients. CONCLUSION: Oligopeptidases, especially Ndel1, which has been strongly correlated with neurodevelopment and brain formation, are potentially a good new target in the study of the neurobiology of BD. LIMITATIONS: The relatively small sample size did not permit to examine the cause-effect relationship of clinical dimensions of BD and the enzymatic activity.

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BACKGROUND: Despite the high incidence and mortality of ST-segment elevation myocardial infarction (STEMI) among the very elderly, risk markers for this condition remain poorly defined. This study was designed to identify independent markers of STEMI among individuals carefully selected for being healthy or manifesting STEMI in < 24 h. METHODS: We enrolled participants aged 80 years or older of whom 50 were STEMI patients and 207 had never manifested cardiovascular diseases. Blood tests, medical and psychological evaluations were obtained at study admission. Odds Ratio (OR) and attributed risk (AR) were obtained by multivariate regression models using STEMI as dependent variable. RESULTS: Low glomerular filtration rate (GFR) [OR:4.41 (1.78-10.95); p = 0.001], reduced levels of HDL-C [OR:10.70 (3.88-29.46); p = 0.001], male gender [OR:12.08 (5.82-25.08); p = 0.001], moderate to severe depressive symptoms [OR:10.00 (2.82-35.50); p = 0.001], prior smoking [OR:2.00 (1.05-3.80); p = 0.034] and current smoking [OR:6.58 (1.99-21.70); p = 0.002] were significantly associated with STEMI. No association was found between STEMI and age, diabetes, hypertension, mild depressive symptoms, triglyceride or LDL-C. CONCLUSIONS: This is the first case-control study carried out with very elderlies to assess STEMI risk. Our findings indicate that reduced HDL-C, GFR, male gender, smoking habits and moderate to severe depressive symptoms are markers of STEMI in this age group. GENERAL SIGNIFICANCE: In Individuals aged 80 or more years, a greater attention must be paid to low HDL-C and GFR at the expense of conventional STEMI risk factors for younger adults such as diabetes mellitus, hypertension and high LDL-C or triglyceride.

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Reduced-antigen-content diphtheria-tetanus-acellular pertussis (dTpa) vaccine, Boostrix™, is indicated for booster vaccination of children, adolescents and adults. The original prefilled disposable dTpa syringe presentation was recently replaced by another prefilled-syringe presentation with latex-free tip-caps and plunger-stoppers. 671 healthy adolescents aged 10-15 years who had previously received 5 or 6 previous DT(P)/dT(pa) vaccine doses, were randomized (1:1) to receive dTpa booster, injected using the new (dTpa-new) or previous syringe (dTpa-previous) presentations. Immunogenicity was assessed before and 1-month post-booster vaccination; safety/reactogenicity were assessed during 31-days post-vaccination. Non-inferiority of dTpa-new versus dTpa-previous was demonstrated for all antigens (ULs 95% CIs for GMC ratios ranged between 1.03-1.13). 1-month post-booster, immune responses were in similar ranges for all antigens with both syringe presentations. dTpa delivered using either syringe presentation was well-tolerated. These clinical results complement the technical data and support the use of the new syringe presentation to deliver the dTpa vaccine.

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The analysis of covariance (ANCOVA) is based on the general linear models. This technique involves a regression model, often multiple, in which the outcome is presented as a continuous variable, the independent variables are qualitative or are introduced into the model as dummy or dichotomous variables, and factors for which adjustment is required (covariates) can be in any measurement level (i.e. nominal, ordinal or continuous). The maneuvers can be entered into the model as 1) fixed effects, or 2) random effects. The difference between fixed effects and random effects depends on the type of information we want from the analysis of the effects. ANCOVA effect separates the independent variables from the effect of co-variables, i.e., corrects the dependent variable eliminating the influence of covariates, given that these variables change in conjunction with maneuvers or treatments, affecting the outcome variable. ANCOVA should be done only if it meets three assumptions: 1) the relationship between the covariate and the outcome is linear, 2) there is homogeneity of slopes, and 3) the covariate and the independent variable are independent from each other.

El análisis de covarianza (ANCOVA) parte de los modelos generales lineales. Esta técnica involucra un modelo de regresión, muchas veces múltiple, en el que el desenlace se presenta como variable continua, la o las maniobras son variables cualitativas que son introducidas al modelo como variables dummy o dicotómicas y los factores por los que se requiere ajustar el análisis (covariables) pueden estar en cualquier nivel de medición (nominal, ordinal o continuo). Las maniobras pueden ser ingresadas al modelo como factores (o efectos) fijos o factores (o efectos) aleatorios. La diferencia entre manejar las maniobras como factor fijo o factor aleatorio depende del tipo de información que se busca en el análisis de los efectos. El ANCOVA separa el efecto de las maniobras del efecto de las covariables, es decir, corrige la variable de respuesta eliminando la influencia de las covariables por el hecho de que estas varían conjuntamente con las maniobras o tratamientos, lo cual afecta la variable de desenlace. El ANCOVA solo debe ser realizado si se cumplen tres supuestos: 1) la relación entre la covariable y el desenlace es lineal, 2) existe homogeneidad de las pendientes y 3) se comprueba la independencia entre la covariable y la maniobra o variable independiente.

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Introdução: Em diversas situações estamos interessados em comparar médias entre dois ou mais grupos. A relação entre estas variáveis pode ser influenciada por uma terceira variável. Esta última é conhecida como covariável e deve ser incluída na análise estatística. Quando essa variável é quantitativa utiliza-se Análise de Covariância (ANCOVA). No contexto da fibrose cística (FC), o volume expiratório forçado no primeiro segundo (VEF1) é uma medida de função pulmonar conhecida por desempenhar importante papel na monitorização de pacientes. Estudos mostram que mulheres com FC apresentaram valores mais baixos de VEF1. Entretanto, a influência da idade também deve ser considerada. Objetivo: Apresentar a aplicabilidade da ANCOVA, suas suposições e a interpretação de seus resultados, através de um exemplo envolvendo a relação entre VEF1 e gênero, considerando a idade dos pacientes como covariável. Métodos: Foram utilizados dados obtidos por simulação, considerando VEF1 com distribuição normal (média=86; DP=21). ANCOVA foi utilizada para avaliar diferença média de VEF1 entre homens e mulheres, ajustada por idade.Resultados: Foram analisados dados de 64 pacientes, idade média de 12 anos (DP=2,5) e VEF1 médio de 85,9 (DP=20,73). Na avaliação inicial do VEF1, as mulheres apresentaram, em média, valores significativamente maiores do que os homens (P=0,021). Entretanto, após o ajuste por idade, esta relação deixou de ser significativa (P=0,100). Conclusão: Esses dados ilustram a influência de uma covariável na relação entre um fator em estudo e o desfecho. Verificou-se a partir da ANCOVA, que o efeito aparente de gênero no VEF1 desaparece com o ajuste para idade do paciente.

Background: In several situations there is an interest in comparing means between two or more groups. The relationship between these variables may be influenced by a third variable, known as covariate, which should be included in the statistical analysis. When the covariate is a quantitative variable, analysis of covariance (ANCOVA) should be used. In the context of cystic fibrosis (CF), forced expiratory volume in 1 second (FEV1) is a measure of pulmonary function known to play an important role in patient monitoring. Studies have shown that women with CF have lower FEV1. However, the influence of age should also be considered. Aim: To demonstrate the applicability of ANCOVA, with assumptions and interpretation of results, using an example involving the relationship between FEV1 and gender, considering patient age as a covariate. Methods: Data were obtained by simulation, considering FEV1 as normally distributed (mean=86; SD=21). ANCOVA was used to assess mean differences in FEV1 between men and women, adjusted for age. Results: Data from 64 patients [mean age: 12 years (SD=2.5)] were analyzed, and mean FEV1 was 85.9 (SD=20.73). At baseline, women had average FEV1 values significantly higher than men (P=0.021). However, after adjusting for age, this relationship was no longer significant (P=0.100). Conclusion: These data illustrate the influence that a covariate may have on the relationship between factors under study and the outcome of interest. ANCOVA revealed that the apparent effect of gender on FEV1 disappears after adjustment for patient age.

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