Comparative analysis of satellite cell properties in heavy- and lightweight strains of turkey

The growth of muscle during postnatal development results partly from the proliferation of satellite cells and their fusion with muscle fibres. We analysed the properties of satellite cells in a heavyweight (HW) turkey strain characterized by high body weight and a fast growth rate, and in a lightweight farm strain (LW) characterized by low body weight and a slow growth rate. Satellite cell activation was then examined in stretched-overloaded anterior latissimus dorsi (ALD) muscle by weighting one wing in young turkeys from both strains. As early as day 1 of stretching for HW and day 2 for LW, small embryonic-like fibres expressing ventricular cardiac myosin heavy chain (MHC) isoform were observed. Following four days of stretching, the number of nascent fibres had increased in both strains but was significantly greater in HW than LW ALD muscle. The proliferation and differentiation capacities of satellite cells from HW and LW strains were investigated in culture. As judged by in vitro measurements of 3H-thymidine incorporation and DNA content, satellite cells of HW turkey exhibited a greater proliferative capability than those of LW turkey. No differences in the temporal appearance of muscle markers (desmin, MHC isoforms) were noted in vitro between the two strains. These data confirm our in vivo observations indicating that selection based on growth rate does not modify muscle fibre maturation. Our in vivo and in vitro observations suggest that variations in the postnatal muscle growth pattern between HW and LW strains may be related to a difference in the capacity of their satellite cells to proliferate. This revised version was published online in August 2006 with corrections to the Cover Date.     

One‐year survival of demented stroke patients: data from the Dijon Stroke Registry,France (1985–2008)

Background and purpose: Dementia is a frequent condition after stroke that may affect the prognosis of patients. Our aim was to determine whether post‐stroke dementia was a predictor of 1‐year case‐fatality and to evaluate factors that could influence survival in demented stroke patients. Methods: From 1985 to 2008, all first‐ever strokes were recorded in the population‐based stroke registry of Dijon, France (150 000 inhabitants). Dementia was diagnosed during the first month following stroke, according to DSM‐III and DSM‐IV criteria. Survival was evaluated at 1 year and multivariate analyses were performed using Cox proportional hazards to identify independent predictive factors. Results: We recorded 3948 first‐ever strokes. Among these stroke patients, 3201 (81%) were testable, and of these, 653 (20.4%) had post‐stroke dementia (337 women and 316 men). Demented patients had lower 1‐year survival than patients without dementia (82.9% vs. 86.9%, P = 0.013). However, in multivariate analysis, dementia did not appear as an independent predictor of 1‐year death. In demented stroke patients, age >80 years old, severe handicap at discharge, recurrent stroke within the first year and subarachnoid haemorrhage were associated with a higher risk of 1‐year death, and the risk was lower in the study period 2003–2008. Conclusions: Dementia after stroke is not independently associated with an increased risk of death at 1 year. In recent years, 1‐year case‐fatality decreased in demented as well as in and non‐demented patients suggesting that improvements in the management of stroke also benefited the most fragile patients.     

Treatment of granuloma annulare with the 595‐nm pulsed dye laser,a multicentre retrospective study with long‐term follow‐up

Background Granuloma annulare (GA) is limited in most cases to isolated lesions, but more widespread generalized forms can be observed. In both cases, the treatment remains highly challenging. Isolated case reports suggested the interest of treating GA with a pulsed dye laser (PDL). Objective To evaluate the PDL in treating GA. Materials and methods Retrospective multicentre study. Each patient should have at least two lesions of GA including at least one that remained untreated to serve as a control. The evaluation was performed on an Investigator Global Assessment for each lesion as compared with baseline. Results Thirteen patients (five with localized GA and eight with generalized GA) with a total of 59 lesions have been treated with a maximum of three PDL sessions. Sixteen lesions (27.1%) achieved >50% of clearing (14% of lesions for generalized GA and 56.2% for localized GA). Transient hyperpigmentation and crusting were observed in 59% and 86% of lesions respectively. The median follow‐up was 6 months (2–12) and 10 lesions (all in generalized GA) recurred after initial clearing. Conclusion Generalized GA showed weak improvement after treatment with a high recurrence rate. Only localized forms showed notable improvement in a more than half of treated lesions. Thus, PDL could be proposed as an alternative approach, but only for localized forms of GA.     

Pathophysiology of Parkinson's disease: Mitochondria,alpha-synuclein and much more…

Parkinson's disease (PD) is a complex, age-related, neurodegenerative disease whose pathogenesis remains incompletely understood. Here, we give an overview of the progress that has been made over the past four decades in our understanding of this disorder. We review the role of mitochondria, environmental toxicants, alpha-synuclein and neuroinflammation in the development of PD. We also discuss more recent data from genetics, which strongly support the endosomal-lysosomal pathways and mitophagy as being central to PD. Finally, we discuss the emerging role of the gut-brain axis as a modulator of PD progression. This article is intended to provide a comprehensive, general and practical review of PD pathogenesis for the general neurologist.     

Spectroscopic data following stroke reveal tissue abnormality beyond the region of T2-weighted hyperintensity

We examined the characteristic clinical features of one family of familial amyotrophic lateral sclerosis (FALS) with a His46Arg mutation in the enzyme Cu/Zn superoxide dismutase-1 (SOD1). The disease duration for this family was 18.1 +/- 13.2 (mean +/- S.D.) years, with the age at onset being 39.7 +/- 10.5 years old (mean +/- S.D.). The initial sign was distal weakness of the unilateral lower limb, extending to the lower limb of the other side. A wheel chair became necessary at 9.8 +/- 3.2 years after the onset. Upper limb weakness started at 15.5 +/- 8.9 years following from the onset. An autopsy was performed on a 71-year-old woman of the family with the mutation. Her disease duration was 47 years, and she died of pneumonia. She had no clear upper motor neuron involvement. Bulbar sign and respiratory muscle weakness had developed 2 years before her death. Neuropathological findings showed degeneration of corticospinal tracts, anterior/posterior spinocerebellar tracts, posterior columns, and Clarke's columns. There were few anterior horn cells in the lumbar spinal cord and no Lewy body-like hyaline inclusion bodies in these remaining anterior horn neurons. This is the first autopsy report of FALS with a His46Arg mutation in the SOD1 enzyme.