Neurocognitive profiles in Duchenne muscular dystrophy and gene mutation site

The presence of nonprogressive cognitive impairment is recognized as a common feature in a substantial proportion of patients with Duchenne muscular dystrophy. To investigate the possible role of mutations along the dystrophin gene affecting different brain dystrophin isoforms and specific cognitive profiles, 42 school-age children affected with Duchenne muscular dystrophy, subdivided according to sites of mutations along the dystrophin gene, underwent a battery of tests tapping a wide range of intellectual, linguistic, and neuropsychologic functions. Full-scale intelligence quotient was approximately 1 S.D. below the population average in the whole group of dystrophic children. Patients with Duchenne muscular dystrophy and mutations located in the distal portion of the dystrophin gene (involving the 140-kDa brain protein isoform, called Dp140) were generally more severely affected and expressed different patterns of strengths and impairments, compared with patients with Duchenne muscular dystrophy and mutations located in the proximal portion of the dystrophin gene (not involving Dp140). Patients with Duchenne muscular dystrophy and distal mutations demonstrated specific impairments in visuospatial functions and visual memory (which seemed intact in proximally mutated patients) and greater impairment in syntactic processing.     

Shape Memory Alloy—Polymer Composites: Static and Fatigue Pullout Strength under Thermo-Mechanical Loading

This work was carried out within the context of an R&D project on morphable polymer matrix composites (PMC), actuated by shape memory alloys (SMA), to be used for active aerodynamic systems in automotives. Critical issues for SMA–polymer integration are analyzed that are mostly related to the limited strength of metal–polymer interfaces. To this aim, materials with suitable thermo-mechanical properties were first selected to avoid premature activation of SMA elements during polymer setting as well as to avoid polymer damage during thermal activation of SMAs. Nonstandard samples were manufactured for both static and fatigue pullout tests under thermo-mechanical loading, which are made of SMA wires embedded in cylindrical resin blocks. Fully coupled thermo-mechanical simulations, including a special constitutive model for SMAs, were also carried out to analyze the stress and temperature distribution in the SMA–polymer samples as obtained from the application of both mechanical loads and thermal activation of the SMA wires. The results highlighted the severe effects of SMA thermal activation on adhesion strength due to the large recovery forces and to the temperature increase at the metal–polymer interface. Samples exhibit a nominal pullout stress of around 940 MPa under static mechanical load, and a marked reduction to 280 MPa was captured under simultaneous application of thermal and mechanical loads. Furthermore, fatigue run-out of 5000 cycles was achieved, under the combination of thermal activation and mechanical loads, at a nominal stress of around 200 MPa. These results represent the main design limitations of SMA/PMC systems in terms of maximum allowable stresses during both static and cyclic actuation.     

Disclosing incidental findings in brain research: The rights of minors in decision‐making

MRI is used routinely in research with children to generate new knowledge about brain development. The detection of unexpected brain abnormalities (incidental findings; IFs) in these studies presents unique challenges. While key issues surrounding incidence and significance, duty of care, and burden of disclosure have been addressed substantially for adults, less empirical data and normative analyses exist for minors who participate in minimal risk research. To identify ethical concerns and fill existing gaps, we conducted a comprehensive review of papers that focused explicitly on the discovery of IFs in minors. The discourse in the 21 papers retrieved for this analysis amply covered practical issues such as informed consent and screening, difficulties in ascertaining clinical significance, the economic costs and burden of responsibility on researchers, and risks (physical or psychological). However, we found little discussion about the involvement of minors in decisions about disclosure of IFs in the brain, especially for IFs of low clinical significance. In response, we propose a framework for managing IFs that integrates practical considerations with explicit appreciation of rights along the continuum of maturity. This capacity‐adjusted framework emphasizes the importance of involving competent minors and respecting their right to make decisions about disclosure. J. Magn. Reson. Imaging 2013;38:1009–1013. © 2013 Wiley Periodicals, Inc.     

Rituximab or Cyclophosphamide in the Treatment of Membranous Nephropathy: The RI-CYCLO Randomized Trial

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The clinicopathologic spectrum of segmental membranous glomerulopathy

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Cancer Risk Associated with Residential Proximity to Industrial Sites: A Review

In this study, the authors sought to review available epidemiologic studies of cancer risk and its association with residence in a neighborhood characterized by industrial sites and to discuss options for future study design. The authors attempted to identify all case-control studies published from January 1980 through July 1997 in which investigators examined exposure resulting from residential proximity to an industrial site neighborhood relative to an increased risk of lung, urinary tract, and lymphohematopoietic malignancies. During these years, some authors reported significant associations between lung cancer risk and residential proximity to (a) smelters, (b) complex industrial areas, and (c) other localized emission sources. There was some evidence that leukemia and lymphomas occurred in the neighborhoods that contained industrial sites.     

Prevalence of SENV-H and SENV-D Virus: Epidemiological Study in Blood Donors and Dialysis Patients

Introduction. Recently, the identification of the SEN virus as a possible etiological agent of parental transmission hepatitis led to the study of the prevalence of such pathogen agents, particularly SENV-H, in our population. This paper compares the rate prevalence in high-risk subjects, such as dialysis patients, and low-risk subjects, such as blood donors. Material and Methods. The study was carried out on SEN virus DNA extracted from serum of dialysis patients and blood donors, and the presence of viral genomes was performed by the nested PCR method. Results. The results showed a higher prevalence in male blood donors, supporting the hypothesis of an epidemiological role for sexual and also parental transmission, as is clearly demonstrated by the high prevalence in dialysis patients. The result reduced the importance of the possible etiological role of the SEN virus due to the high percentage of positivity in healthy population, and it induces one to consider poorly significant the pathogenicity of such viral agents. Conclusion. For this instance, the authors, in agreement with the phylogenically related TT virus, described SEN viruses as absolutely not pathogens and considered them as “simple guests.”     

Do osteotomies of the proximal femur still have a role?

Trochanteric valgus and varus correction osteotomies have been described with or without associated rotational correction. In the last decade, new techniques have been described, including femoral neck osteotomy, femoral head reorientation, relative neck lengthening, greater or lesser trochanter distalization, and femoral head reduction osteotomy. While the overall number of femoral osteotomies in the young patients has decreased because of the efficacy of primary total hip arthroplasties, those osteotomy techniques may expand the indications for femoral osteotomies in select patients who meet the indications.