ABSTRACT Introduction: Telomere length (TL) is a biomarker of cellular proliferative history. In healthy individuals, leukocyte TL shortens with age and associates with the lifespan of men and women. However, most of studies had used linear regression models to address the association of the TL attrition, aging and sex. Methods: We evaluated the association between the TL, aging and sex in a cohort of 180 healthy subjects by quantile regression. The TL of nucleated blood cells was measured by fluorescent in situ hypridization (flow-FISH) in a cohort of 89 men, 81 women, and 10 umbilical cord samples. The results were validated by quantitative polymerase chain reaction (qPCR) and compared to a linear regression analysis. Results: By quantile regression, telomere dynamics slightly differed between sexes with aging: women had longer telomeres at birth and slower attrition rate than men until the sixth decade of life; after that, TL eroded faster and became shorter than that in men. These differences were not observed by linear regression analysis, as the overall telomere attrition rates in women and men were similar (42 pb per year, p < 0.0001 vs. 45 pb kb per year, p < 0.0001). Also, qPCR did not recapitulate flow-FISH findings, as the telomere dynamics by qPCR followed a linear model. Conclusion: The quantile regression analysis accurately reproduced a third-orderpolynomial TL attrition rate in both women and men, but it depended on the technique applied to measure TL. The Flow-FISH reproduced the expected telomere dynamics through life and, differently from the qPCR, was able to detect the subtle TL variations associated with sex and aging.

Resumen En este artículo introducimos un nuevo modelo Bayesiano para distribuciones Weibull segmentadas, que puede ser una buena alternativa en el análisis de datos aplicados a la investigación en salud, con la presencia de censuras y covariables. Con este método basado en la estimación de puntos de cambio, hemos obtenido un excelente ajuste a los datos utilizados como ejemplos. De acuerdo con el modelo propuesto, fue posible identificar rangos de valores en las series temporales en que una variable independiente podría tener diferentes efectos. Este es un resultado importante desde el punto de vista clínico. Los estimados bayesianos fueron obtenidos usando métodos de Monte Carlo en Cadenas de Markov. Ejemplos basados en conjuntos de datos reales fueran usados para ilustrar el uso de los modelos propuestos y sus potenciales aplicaciones en investigaciones clínicas.

Abstract In this paper, we introduce a Bayesian approach for segmented Weibull distributions which could be a good alternative to analyze medical survival data in the presence of censored observations and covariates. With the obtained Bayesian estimated change-points we could get an excellent fit of the proposed model to any data sets. With the proposed methodology, it is also possible to identify survival times intervals where a covariate could have significantly different effects when compared to other lifetime intervals, an important point under a clinical view. The obtained Bayesian estimates are obtained using standard Markov Chain Monte Carlo methods. Some examples with real data sets illustrate the proposed methodology and its potential clinical value.

ABSTRACT In this paper, we discuss computational aspects to obtain accurate inferences for the parameters of the generalized gamma (GG) distribution. Usually, the solution of the maximum likelihood estimators (MLE) for the GG distribution have no stable behavior depending on large sample sizes and good initial values to be used in the iterative numerical algorithms. From a Bayesian approach, this problem remains, but now related to the choice of prior distributions for the parameters of this model. We presented some exploratory techniques to obtain good initial values to be used in the iterative procedures and also to elicited appropriate informative priors. Finally, our proposed methodology is also considered for data sets in the presence of censorship.

BACKGROUND: Grip strength is used to infer functional status in several pathological conditions, and the hand dynamometer has been used to estimate performance in other areas. However, this relationship is controversial in neuromuscular diseases and studies with the bulb dynamometer comparing healthy children and children with Duchenne Muscular Dystrophy (DMD) are limited. OBJECTIVE: The evolution of grip strength and the magnitude of weakness were examined in boys with DMD compared to healthy boys. The functional data of the DMD boys were correlated with grip strength. METHOD: Grip strength was recorded in 18 ambulant boys with DMD (Duchenne Group, DG) aged 4 to 13 years (mean 7.4±2.1) and 150 healthy volunteers (Control Group, CG) age-matched using a bulb dynamometer (North Coast- NC70154). The follow-up of the DG was 6 to 33 months (3-12 sessions), and functional performance was verified using the Vignos scale. RESULTS: There was no difference between grip strength obtained by the dominant and non-dominant side for both groups. Grip strength increased in the CG with chronological age while the DG remained stable or decreased. The comparison between groups showed significant difference in grip strength, with CG values higher than DG values (confidence interval of 95%). In summary, there was an increment in the differences between the groups with increasing age. Participants with 24 months or more of follow-up showed a progression of weakness as well as maintained Vignos scores. CONCLUSIONS: The amplitude of weakness increased with age in the DG. The bulb dynamometer detected the progression of muscular weakness. Functional performance remained virtually unchanged in spite of the increase in weakness.

OBJECTIVE: Subjects exposed to laboratory animals are at a heightened risk of developing respiratory and allergic diseases. These diseases can be prevented by simple measures such as the use of personal protective equipment. We report here the primary findings of the Laboratory Animals and Respiratory Allergies Study regarding the prevalence of allergic diseases among laboratory animal workers, the routine use of preventive measures in laboratories and animal facilities, and the need for prevention programs. METHODS: Animal handlers and non-animal handlers from 2 Brazilian universities (University of São Paulo and State University of Campinas) answered specific questionnaires to assess work conditions and symptoms. These subjects also underwent spirometry, a bronchial challenge test with mannitol, and skin prick tests for 11 common allergens and 5 occupational allergens (rat, mouse, guinea pig, hamster, and rabbit). RESULTS: Four hundred fifty-five animal handlers (32±10 years old [mean±SD], 209 men) and 387 non-animal handlers (33±11 years old, 121 men) were evaluated. Sensitization to occupational allergens was higher among animal handlers (16%) than non-animal handlers (3%, p<0.01). Accessibility to personal protective equipment was measured at 85% (median, considering 73 workplaces of the animal handler group). Nineteen percent of the animal handlers indicated that they wear a respirator at all times while handling animals or working in the animal room, and only 25% of the animal handlers had received an orientation about animal-induced allergies, asthma, or rhinitis. CONCLUSION: In conclusion, our data indicate that preventive programs are necessary. We suggest providing individual advice to workers associated with institutional programs to promote a safer work environment.

OBJETIVO: Estimar a probabilidade pré-teste do diagnóstico de síndrome de Cushing (SC) por meio de julgamento clínico utilizando abordagem Bayesiana. MATERIAIS E MÉTODOS: Médicos responderam a três perguntas, em sete congressos de endocrinologia. Após obtenção da história clínica/exame físico, sem exames laboratoriais, apenas com base em sua experiência pessoal, qual a probabilidade de diagnosticar SC?; Há quanto tempo você pratica endocrinologia?; Onde você trabalha? Uma regressão beta Bayesiana, utilizando o software WinBugs, foi empregada. RESULTADOS: Foram obtidos 294 questionários. A estimativa Bayesiana da probabilidade média de diagnosticar SC foi 51,6% (IC 95%: 48,7-54,3). Houve relação direta entre probabilidade de diagnosticar SC e experiência da prática endócrina, porém não com o local de trabalho. CONCLUSÃO: A probabilidade pré-teste do diagnóstico de SC foi estimada utilizando uma metodologia Bayesiana. Embora a probabilidade pré-teste possa ser dependente do contexto, a experiência de anos de prática pode auxiliar no diagnóstico intuitivo da CS. Arq Bras Endocrinol Metab. 2012;56(9):633-7

OBJECTIVE: To estimate the pretest probability of Cushing's syndrome (CS) diagnosis by a Bayesian approach using intuitive clinical judgment. MATERIALS AND METHODS: Physicians were requested, in seven endocrinology meetings, to answer three questions: "Based on your personal expertise, after obtaining clinical history and physical examination, without using laboratorial tests, what is your probability of diagnosing Cushing's Syndrome?"; "For how long have you been practicing Endocrinology?"; and "Where do you work?". A Bayesian beta regression, using the WinBugs software was employed. RESULTS: We obtained 294 questionnaires. The mean pretest probability of CS diagnosis was 51.6% (95%CI: 48.7-54.3). The probability was directly related to experience in endocrinology, but not with the place of work. CONCLUSION: Pretest probability of CS diagnosis was estimated using a Bayesian methodology. Although pretest likelihood can be context-dependent, experience based on years of practice may help the practitioner to diagnosis CS. Arq Bras Endocrinol Metab. 2012;56(9):633-7

CONTEXTUALIZAÇÃO: Na reabilitação, a imobilização em alongamento do músculo esquelético é realizada como contramedida para reverter efeitos de encurtamento muscular severo e em eventos pós-cirúrgicos. Acredita-se que o retorno às atividades funcionais normais estimule mecanotransdutores capazes de reorganizar a citoarquitetura normal muscular, porém a descrição das alterações histopatológicas relacionadas a esses procedimentos são escassas na literatura. OBJETIVOS: Avaliar e quantificar anomalias histológicas induzidas pela imobilização em alongamento do músculo EDL (Extensor Digitorum Longus) e confrontá-las com a livre movimentação do animal após esse procedimento. MÉTODOS: Foram utilizadas 18 ratas Wistar, distribuídas nos grupos: controle (GC); imobilizadas em flexão plantar (EDL em posição alongada) por 14 dias (GI); imobilizadas por 14 dias e liberadas por dez dias (GIL). Fragmentos do EDL foram congelados, seccionados e processados com reações imuno-histoquímica para colágenos I e III e histoquímica para Adenosina Trifosfatase Miofibrilar e Hematoxilina-Eosina. RESULTADOS: Os animais do GI apresentaram discreto aumento da expressão de colágeno I e de fibras em processo degenerativo/necrótico, redução da proporção de fibras tipo (FT) 2A e do diâmetro menor de todos os tipos de fibras, quando comparados com os animais do GC. Para o GIL, observou-se retorno da quantidade de colágeno I às condições controle, além de redução na proporção de FT2D, aumento do número de núcleos centralizados e do diâmetro menor das fibras quando comparadas com o GI, porém a expressão de FT2B e FT2D não atingiu os valores de referência. CONCLUSÕES: Os dados apresentados mostram que a retomada da função durante dez dias foi parcialmente eficiente na recuperação das características do músculo EDL após o período de imobilização e que, se extrapolados os dados à clínica fisioterapêutica, a adoção de procedimentos orientados às disfunções primárias do músculo pode favorecer a resposta morfofuncional do segmento e o seu íntegro restabelecimento.

BACKGROUND: In rehabilitation, immobilization of skeletal muscles in the elongated position is performed as a countermeasure in order to reverse the effects of severe muscle shortening and postoperative events. The return to normal functional activities is believed to stimulate mechanotransducers capable of reorganizing the normal muscle cytoarchitecture, but few data describing the histopathological changes relating to these procedures are available in the literature. OBJECTIVES: To assess and quantify histological abnormalities induced by immobilization of the extensor digitorum longus (EDL) muscle in elongation and to compare them with free movement of the animal after this procedure. METHODS: Eighteen female Wistar rats were used, divided into the following groups: Control; Immobilized in plantar flexion (EDL in an elongated position) for 14 days (GI); Immobilized for 14 days and released for 10 days (GIL). EDL fragments were frozen, sectioned and processed through immunohistochemical reactions for collagens I and III and histochemical methods for myofibrillar adenosine triphosphatase using hematoxylin-eosin. RESULTS: GI animals presented slight increases in collagen I and fiber expression in a degenerative/necrotic process, and reductions in the proportion of FT2A fibers and in the diameters of all fiber types, compared with the controls. In GIL, the quantity of collagen I returned to control conditions; the proportion of FT2D decreased; the number of centralized nuclei increased; and the fiber diameter was smaller than in GI. However, FT2B and FT2D expression did not reach the reference values. CONCLUSIONS: The data presented show that the recovery of function over a 10-day period was partially efficient with regard to recuperation of the characteristics of the EDL muscle after the period of immobilization. If the data are extrapolated to physiotherapeutic clinical practice, use of procedures directed towards primary dysfunctions of the muscle may favor a morphofunctional response in the segment and its full recovery.

Os riscos envolvidos na transfusão de sangue e hemoderivados podem ser conseqüentes de procedimentos inadequados, erros ou omissões dos profissionais responsáveis pela transfusão. O presente estudo objetivou determinar o nível de conhecimento sobre o assunto e a adequação das práticas transfusionais dos profissionais de Enfermagem que atuam em um grande hospital universitário do interior de São Paulo. O estudo foi realizado durante um treinamento teórico em Hemoterapia, onde foi aplicado um instrumento de coleta de dados antes e após o treinamento, caracterizando estes profissionais e avaliando seus conhecimentos sobre o tema. Participaram enfermeiros, auxiliares e técnicos de enfermagem responsáveis pela administração de transfusões. Mais da metade se sente pouco ou mal informada sobre o assunto. Grande parte referiu que os pacientes não são orientados sobre sinais e sintomas de reações transfusionais, ainda referindo procedimentos incorretos para aquecimento do sangue. A avaliação de conhecimentos evidenciou lacunas importantes na capacitação destes profissionais.

The risks involved in blood and blood component transfusion can be caused by inadequate procedures and mistakes or omissions by professionals responsible for transfusion. The present study aims at evaluating the level of knowledge on this issue and about the adequacy of the transfusional practices of nurses at a large university hospital in the State of São Paulo, Brazil. The study was conducted during an in-service training course on hemotherapy. A data collection instrument was applied before and after the training, when the professionals were asked about their knowledge of transfusion practices. Study participants were nurses and nursing assistants, all of whom were responsible for transfusion procedures. More than half the participants felt that they were given little information or were badly informed about transfusions. A large portion of the professionals mentioned that the signs and symptoms of transfusion reactions are not explained to patients. Many participants reported inadequate blood warming procedures. The evaluation of the knowledge showed significant defects in the education of these nursing professionals.