Object The most appropriate method to determine the quality of life of patients with intradural primary spinal tumors (IPSTs) is not still well established. Methods Clinical data in 234 patients who underwent surgery for intradural spinal disease were collected prospectively. The 36-Item Short Form Health Survey (SF-36), a generic score scale, was administered to 148 patients with IPSTs to demonstrate if the survey can be used to effectively evaluate these patients. Forty-eight patients were excluded because they did not complete the protocol. The study was finally conducted with 100 patients (45 male and 55 female) with IPSTs, and the results were compared with those of 2 other scales: the McCormick scale and the Aminoff-Logue scale. Results Construct validity was demonstrated by confirming the hypothesized relationship between the scores of the SF-36 and the McCormick scale (p = 0.003), the Aminoff-Logue gait subscale (p = 0.025), the Aminoff-Logue micturition subscale (p = 0.013), and the Aminoff-Logue defecation subscale (p = 0.004). Reliability was demonstrated for all 8 SF-36 domain scales and the Physical Component Summary and the Mental Component Summary of the SF-36, where in each the Cronbach alpha satisfied the Nunnally criterion of > 0.85. Conclusions The authors' results demonstrated that SF-36 provides valid and reliable data for patients with IPSTs and that the survey can be used appropriately to evaluate these patients.

The method presented in this work intends to analyze drum brake design parameters of a light duty automotive drum brake system. The main objective of this work is to correlate brake materials and unstability parameters to identify which condition will effectively reduce squeal propensity. The methodology involves (a) the finite-element method of the brake components, namely, drum, shoes, and frictional linings, (b) static calculations to get a pre-stress state around which (c) is computed the complex eigenvalues of the system. Hence, positive real parts indicate dynamic instabilities which are explored by varying parameters, namely, the modulus of elasticity of the materials and the friction coefficient at the contact of the shoes with the drum. According to calculations, it was observed that there exist a given range of values for Young’s modulus and friction coefficient that are favorable to reduce drum brake squeal occurrence. In addition, the method proposed delivered results that match with brake squeal literature.

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One of the factors of influence on driver comfort is undoubtedly the noise. The noise generated by the brake, in addition to causing discomfort, can cause uncertainty as to the existence of mechanical failure in the brake system. Among the types of noise related to disc brakes, what has been generating a greater interest of researchers is squeal noise. This research paper is concerned with the disc brake squeal problem for motorcycles. The aim of the present research is developing a finite element model of the motorcycle disc brake in order to improve the understanding of the influence of material and operational parameters on squeal generation. Stability analysis of the disc brake assembly was accomplished to find unstable frequencies. A parametric study was carried out to investigate the effect of changing Young's modulus of the disc, back plate, friction material and operational parameters, as rotational velocity of the disc, pressure and temperature, on squeal generation. The results of simulation indicated that material and operational parameters play a substantial role in generating the squeal noise.

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Osteogenesis imperfecta (OI) is a rare hereditary condition caused by changes in collagen metabolism. It is classified into four types according to clinical, genetic, and radiological criteria. Clinically, bone fragility, short stature, blue sclerae, and locomotion difficulties may be observed in this disease. OI is often associated to severe dental problems, such as dentinogenesis imperfecta (DI) and malocclusions. Radiographically, affected teeth may have crowns with bulbous appearance, accentuated constriction in the cementoenamel junction, narrowed roots, large root canals due to defective dentin formation, and taurodontism (enlarged pulp chambers). There is no definitive cure, but bisphosphonate therapy is reported to improve bone quality; however, there is a potential risk of bisphosphonate-related osteonecrosis of the jaw. In this study we report a case of OI in a male pediatric patient with no family history of OI who was receiving ongoing treatment with intravenous perfusion of bisphosphonate and who required dental surgery. In addition, we discussed the clinical and imaging findings and briefly reviewed the literature.

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The aim of the present study was to investigate the association between polymorphism in the interleukin-10 gene promoter at position -1082 in human immunodeficiency virus-infected patients who had presented allergic reaction due to efavirenz. The study included 63 patients treated at the Hospital São José de Doenças Infecciosas, Fortaleza, Ceará, Brazil. Twenty-one patients who had presented allergic reaction to efavirenz were compared to 42 patients with no allergic reaction following exposure to this drug. Blood samples were collected for DNA extraction and submitted to the restriction fragment length polymorphism - polymerase chain reaction technique. The -1082AA genotype was significantly more frequent in allergic patients as compared to non-allergic patients (p=0.019; χ(2)=5.534; OR=3.625; 95% CI=1.210-10.860). Likewise the allele IL-10 -1082A was identified significantly more often among efavirenz allergic patients than in the non-allergic group (p=0.009; χ(2)=6.787; OR=3.029; 95% CI=1.290-7.111). These findings suggest that the polymorphism in the interleukin-10 gene promoter -1082G/A can be related to the development of allergic reactions to efavirenz.