Comparison between Highly Complex Location Models and GAMLSS.

This paper presents a discussion regarding regression models, especially those belonging to the location class. Our main motivation is that, with simple distributions having simple interpretations, in some cases, one gets better results than the ones obtained with overly complex distributions. For instance, with the reverse Gumbel (RG) distribution, it is possible to explain response variables by making use of the generalized additive models for location, scale, and shape (GAMLSS) framework, which allows the fitting of several parameters (characteristics) of the probabilistic distributions, like mean, mode, variance, and others. Three real data applications are used to compare several location models against the RG under the GAMLSS framework. The intention is to show that the use of a simple distribution (e.g., RG) based on a more sophisticated regression structure may be preferable than using a more complex location model.

Linear mixed-effects models for the analysis of high-density electromyography with application to diabetic peripheral neuropathy.

This article demonstrates the power and flexibility of linear mixed-effects models (LMEMs) to investigate high-density surface electromyography (HD-sEMG) signals. The potentiality of the model is illustrated by investigating the root mean squared value of HD-sEMG signals in the tibialis anterior muscle of healthy (n = 11) and individuals with diabetic peripheral neuropathy (n = 12). We started by presenting the limitations of traditional approaches by building a linear model with only fixed effects. Then, we showed how the model adequacy could be increased by including random effects, as well as by adding alternative correlation structures. The models were compared with the Akaike information criterion and the Bayesian information criterion, as well as the likelihood ratio test. The results showed that the inclusion of the random effects of intercept and slope, along with an autoregressive moving average correlation structure, is the one that best describes the data (p < 0.01). Furthermore, we demonstrate how the inclusion of additional variance structures can accommodate heterogeneity in the residual analysis and therefore increase model adequacy (p < 0.01). Thus, in conclusion, we suggest that adopting LMEM to repeated measures such as electromyography can provide additional information from the data (e.g. test for alternative correlation structures of the RMS value), and hence provide new insights into HD-sEMG-related work.

Modeling the Angle-Specific Isokinetic Hamstring to Quadriceps Ratio Using Multilevel Generalized Additive Models.

Background and Objectives: This study considered the use of a generalized additive multilevel model to describe the joint-angle-specific functional hamstring to quadriceps ratio (H:Q ratio) in the knee, using all of the available truly isokinetic data within the range. Materials and Methods: Thirty healthy male basketball players aged 15.0 (1.4) years (average stature = 180.0 cm, SD = 11.1 cm; average body mass = 71.2, SD = 14.9 kg) years were considered. All players considered had no history of lower extremity musculoskeletal injury at the time of testing or during the 6 months before testing, and had been engaged in formal basketball training and competition for 5.9 (2.4) years. Moments of force of the reciprocal concentric and eccentric muscular actions for the knee extensors and flexors assessed by isokinetic dynamometry at 60°âˆ™s-1 were used. Results: Maximum moments of force were attained at different angle positions for knee extension. For knee flexion, it was apparent that there was an ability to maintain high levels of moment of force between 30° and 60° in the concentric muscular action, corresponding to the concentric action of the hamstrings. However, for the eccentric knee flexion, corresponding to the quadriceps action, there was a marked peak of moment of force at about 55°. The functional H:Q ratio for the knee extension was non-linear, remaining higher than 1.0 (i.e., point of equality) from the beginning of the extension until approximately 40° of the knee extension, leveling off below the point of equality thereafter. On average, the functional H:Q ratio for the knee flexion did not attain 1.0 across the range of motion. The functional H:Q ratio for the knee in the present sample peaked at 20° and 80°, declining between these angle positions to below 0.50 at about 0.54. Conclusions: Estimating the form of the non-linear relationship on-the-fly using a generalized additive multilevel model provides joint-angle-specific curves and joint-angle-specific functional H:Q ratio patterns, allowing the identification and monitoring of strength development, with potential implications for injury and performance.

Predicting survival function and identifying associated factors in patients with renal insufficiency in the metropolitan area of Maringá, Paraná State, Brazil.

Renal insufficiency is a serious medical and public health problem worldwide. Recently, although many surveys have been developed to identify factors related to the lifetime of patients with renal insufficiency, controversial results from several studies suggest that researches should be conducted by region. Thus, in this study we aim to predict and identify factors associated with the lifetime of patients with chronic renal failure (CRF) in the metropolitan area of Maringá, Paraná State, Brazil, based on the generalized additive models for location, scale and shape (GAMLSS) framework. Data used in this study were collected from the Maringá Kidney Institute and comprehends 177 patients (classified with CRF and mostly being treated under the Brazilian Unified National Health System) enrolled in a hemodialysis program from 1978 up to 2010. By using this approach, we concluded that in other regions, gender, kidney transplant indicator, antibodies to hepatitis B and antibodies to hepatitis C are significant factors that affect the expected lifetime.

Predicting survival function and identifying associated factors in patients with renal insufficiency in the metropolitan area of Maringá, Paraná State, Brazil / A predição da função de sobrevivência e identificação de fatores associados em pacientes renais crônicos na área metropolitana de Maringá, Paraná, Brasil / Prediciendo la esperanza de vida e identificando factores asociados en pacientes con insuficiencia renal en el área metropolitana de Maringá, Estado de Paraná, Brasil

Renal insufficiency is a serious medical and public health problem worldwide. Recently, although many surveys have been developed to identify factors related to the lifetime of patients with renal insufficiency, controversial results from several studies suggest that researches should be conducted by region. Thus, in this study we aim to predict and identify factors associated with the lifetime of patients with chronic renal failure (CRF) in the metropolitan area of Maringá, Paraná State, Brazil, based on the generalized additive models for location, scale and shape (GAMLSS) framework. Data used in this study were collected from the Maringá Kidney Institute and comprehends 177 patients (classified with CRF and mostly being treated under the Brazilian Unified National Health System) enrolled in a hemodialysis program from 1978 up to 2010. By using this approach, we concluded that in other regions, gender, kidney transplant indicator, antibodies to hepatitis B and antibodies to hepatitis C are significant factors that affect the expected lifetime.

A insuficiência renal crônica é um grave problema clínico e de saúde pública no mundo inteiro. Recentemente, apesar de muitas pesquisas já realizadas para identificar os fatores relacionados à evolução dos pacientes renais crônicos, os resultados conflitantes entre diversos estudos sugerem a necessidade de pesquisas por região. Portanto, o estudo busca predizer e identificar os fatores associados à evolução dos pacientes com insuficiência renal crônica (IRC) na área metropolitana de Maringá, Estado do Paraná, Brasil, com base nos modelos aditivos generalizados para localização, escala e forma (GAMLSS). Os dados utilizados neste estudo foram coletados no Instituto do Rim de Maringá e incluem 177 pacientes (classificados com IRC, a maioria tratada no Sistema Único de Saúde) inclusos no programa de hemodiálise entre 1978 e 2010. Através dessa abordagem, concluímos que em outras regiões, gênero, indicação para transplante renal e anticorpos aos vírus das hepatites B e C são fatores significativos que afetam a sobrevivência esperada.

La insuficiencia renal representa un problema médico y de salud pública serio en todo el mundo. Recientemente, pese a los muchos estudios que se han desarrollado para identificar factores relacionados con la esperanza de vida de los pacientes con insuficiencia renal, los resultados controvertidos de algunos estudios sugieren que las investigaciones deberían realizarse por regiones. No obstante, en este trabajo pretendemos predecir e identificar los factores asociados con la esperanza de vida de pacientes con fallo renal crónico (FRC) en el área metropolitana de Maringá, Estado de Paraná, Brasil, basado en el marco de modelos aditivos generalizados para ubicación, escala y forma (GAMLSS por sus siglas en inglés). Los datos usados en este estudio fueron recogidos del Instituto del riñón de Maringá y comprende a 177 pacientes (clasificados con FRC y en su mayoría siendo tratados en el Sistema Único de Salud), inscritos en un programa de hemodiálisis desde 1978 hasta 2010. Usando este enfoque, concluimos que en otras regiones, género, indicador de trasplante de riñón, anticuerpos a la hepatitis B y anticuerpos a la hepatitis C son factores significativos que afectan a la esperanza de vida.

[Acute hepatic failure in a patient with hyperthyroidism and virus B hepatitis: recovery after plasmapheresis and thyroidectomy--a case report]. / Disfunção hepática aguda em paciente com hipertireoidismo e hepatite por vírus B: recuperação após plasmaférese e tireoidectomia--relato de caso.

A 31-year-old man admitted with abdominal pain, nauseas, vomiting, jaundice and fever that had began 2 weeks before. He had a history of hyperthyroidism and an irregular treatment with propylthiouracil (PTU) for 2 years. He had stopped PTU when the current symptoms started. The patient presented diffuse goiter, about 120g, FT4 22.7 ng/dL (N: 0.8 - 1.9 ng/dL); THS < 0.002 microUI/mL (N 0.4-5 microUI/mL). Transaminases, serum total and direct bilirubins were increased. He was kept without PTU and propranolol was started and increased until the dose of 480 mg/day. Abdominal ultrasonography was normal and serologic markers for hepatitis A, B and C pointed to acute virus B hepatitis. The patient presented a worse of hepatic function and elevated thyroid hormones levels. To avoid the future need of antithyroid drugs, to get a fast normalization of thyroid hormones levels and because of the goiter size thyroidectomy was recommended. The patient underwent one therapeutic plasmapheresis session just before the surgery. A total thyroidectomy was performed without complications. At the 5th day after surgery the patient presented improvement of hepatic function and low FT4 serum levels. We concluded that preexisting hyperthyroidism may aggravate or perpetuate a hepatic failure caused for acute viral hepatitis and plasmapheresis is a rapid, reliable and effective way to lower thyroid hormones serum levels, allowing a successful thyroidectomy in patients with severe thyrotoxicosis.

Disfunção hepática aguda em paciente com hipertireoidismo e hepatite por vírus B: recuperação após plasmaférese e tireoidectomia - relato de caso / Acute hepatic failure in a patient with hyperthyroidism and virus B hepatitis: recovery after plasmapheresis and thyroidectomy - a case report

Paciente masculino, 31 anos, internado com quadro de dor abdominal, náuseas, vômitos, icterícia e febre, iniciado há duas semanas. História de hipertireoidismo e tratamento irregular com propiltiuracil há dois anos, interrompeu a medicação quando iniciou o quadro atual. Apresentava bócio difuso, cerca de 120 g, T4L 22,7 ng/dL (VN 0,8-1,9 ng/dL); TSH < 0,002 µUI/mL (VN 0,4-5 µUI/mL). Transaminases, bilirrubinas total e direta séricas elevadas. Foi mantido sem antitireoidiano e iniciado propranolol até a dose de 480 mg/dia. Ultra-sonografia de abdome foi normal e sorologias para hepatites A, B e C indicaram infecção aguda por vírus B. Ocorreu piora da função hepática e manutenção de níveis elevados de hormônios tireoidianos. Visando evitar necessidade futura de antitireoidiano, obter rápida normalização dos níveis de hormônios tireoidianos e em virtude do tamanho do bócio foi indicado tireoidectomia. O paciente foi submetido a uma sessão de plasmaférese terapêutica, imediatamente antes da cirurgia, e tireoidectomia subtotal sem intercorrências. No quinto dia após a cirurgia, o paciente apresentava melhora da função hepática e baixos níveis séricos de T4 livre. Concluímos que o hipertireoidismo prévio pode exacerbar e perpetuar a disfunção hepática causada por hepatite viral aguda e que a plasmaférese é um meio rápido, seguro e eficaz de reduzir os níveis de hormônio tireoidiano, permitindo uma tireoidectomia bem-sucedida em pacientes com tireotoxicose grave.

A 31-year-old man admitted with abdominal pain, nauseas, vomiting, jaundice and fever that had began 2 weeks before. He had a history of hyperthyroidism and an irregular treatment with propylthiouracil (PTU) for 2 years. He had stopped PTU when the current symptoms started. The patient presented diffuse goiter, about 120g, FT4 22.7 ng/dL (N: 0.8 - 1.9 ng/dL); THS < 0.002 µUI/mL (N 0.4-5 µUI/mL). Transaminases, serum total and direct bilirubins were increased. He was kept without PTU and propranolol was started and increased until the dose of 480 mg/day. Abdominal ultrassonography was normal and serologic markers for hepatitis A, B and C pointed to acute virus B hepatitis. The patient presented a worse of hepatic function and elevated thyroid hormones levels. To avoid the future need of antithyroid drugs, to get a fast normalization of thyroid hormones levels and because of the goiter size thyroidectomy was recommended. The patient underwent one therapeutic plasmapheresis session just before the surgery. A total thyroidectomy was performed without complications. At the 5th day after surgery the patient presented improvement of hepatic function and low FT4 serum levels. We concluded that preexisting hyperthyroidism may aggravate or perpetuate a hepatic failure caused for acute viral hepatitis and plasmapheresis is a rapid, reliable and effective way to lower thyroid hormones serum levels, allowing a successful thyroidectomy in patients with severe thyrotoxicosis.

Esporotricose pulmonar: relato de caso / Pulmonay sporotrichosis: a case report

Os autores relatam o caso de um homem de 49 anos, com quadro de síndrome consumptiva e múltiplas cavitações pulmonares há cinco anos. Foi tratado para tuberculose, em duas ocasiões, sem melhora da sintomatologia. O paciente foi internado com quadro de dispnéia em repouso e febre, sendo sua cultura de escarro positiva para Sporothrix schenckii. O objetivo deste trabalho é apresentar uma forma rara de esporotricose e ressaltar a importância de seu reconhecimento.

A 49 year-old white man was admitted with dyspnea, cough and fever, with a history of consumptive syndrome and pulmonary cavitary disease for the past five years. He was treated twice for pulmonary tuberculosis previously, but without responses. His sputum culture was positive for Sporothrix schenckii. The ocurrence of sporotrichosis as a disease of the lung without cutaneos involvement is rare. So the subject of this report is to describe a case of pulmonary sporotrichosis and show the importance of its recognition.

Pneumonia tuberculosa / Tuberculous pneumonia

Os achados clínicos da tuberculose variam amplamente e dependem de um número de fatores, incluindo a eficácia das defesas do hospedeiro em conter a população bacilar. Os autores descrevem um caso de pneumonia tuberculosa em um homem com 46 anos de idade que evoluiu para insuficiência respiratória aguda e morreu cinco dias após a internação. O diagnóstico definitivo foi dado na autópsia