Myosin light chains and muscle pathology

We evaluated the isoform composition of heavy and light chains of myosin in single muscle fibers from patients with Duchenne dystrophy, myotonic dystrophy, or polymyositis. In all myopathic muscles, there was an increase in the proportion of intermediate fibers which, by analysis of myosin isoforms, fell into two subpopulations, one that contained both fast and slow myosin and another that contained myosin molecular hybrids. The increased proportion of intermediate (or transitional) fibers suggests changes in the equilibrium between fast and slow motor units. These changes could result from regeneration and subsequent maturation of fibers or from direct transformation of mature fibers of one type into the opposite.     

Older adults’ preferences for exercising alone versus in groups: Considering contextual congruence

Background: A growing body of research suggests that older exercisers prefer to exercise alone rather than in group-based settings. One limitation of these studies, however, has been that researchers have failed to take into account the age-related characteristics of groups when asking adults about their preferences for exercise settings.Purpose: The overall purpose of this study was to examine the exercise preferences of 947 adults for involvement in standard exercise classes populated by participants from various categories across the age spectrum.Results: The results revealed that when faced with the prospect of exercising with considerably older or younger exercisers, participants found such an exercise context to be largely unappealing. However, in accordance with the basic tenets of self-categorization theory, the results revealed that older and younger adults alike express a positive preference for exercising in standard exercise classes comprised of similarly aged participants.Conclusions: The findings of this study challenge a growing call for exercise interventions for older adults to be primarily directed at the individual-level, and suggest that group-related intervention strategies may indeed be attractive to older exercisers.     

Pneumonia Disease Assessment using a Slaughterhouse Lung‐Scoring Method

The aims of this study were the evaluation of a quantitative method for the assessment of pneumonia lesions applied to heavy‐weight slaughtered pigs, the identification of risk factors connected with the increase in the prevalence and severity of the lesions and the evaluation of a possible correlation between the presence of pneumonia lesions and the decrease in the carcass quality. The lungs of 10 041 pigs (109 slaughtered batches) coming from 91 farms located in Northern Italy were examined. Lung lesions were scored using the method developed by Madec and Kobisch (Journ. Rech. Porc. Fr., 14 , 1982 , 405). Before the scoring, anamnestic information regarding the farm of origin of each batch were collected. For 41 batches (3603 pigs), information about carcass quality were also collected. Pneumonia lesions were found in 59.6% of the lungs (range 3–91%), and the average batch score was 2.11 (range 0.03–7.15). We identified as farm risk factors those related to an increase in the severity of the lung lesions, the presence of breeders within the herd, the starting of a growing cycle during the winter season and the lack of vaccination programmes to Mycoplasma hyopneumoniae. Moreover, we also found a statistically significant association between the increase in the mean lung score of the batch and the decrease of the carcass quality.     

Early increase of oxidative stress and soluble CD40L in children with hypercholesterolemia.

OBJECTIVES: The aim of the study was to analyze the behavior of oxidative stress and its interplay with CD40L, a protein that is implicated in atherosclerosis, in hypercholesterolemic children. BACKGROUND: Oxidative stress has been suggested to play a major role in premature atherosclerosis. METHODS: Forty-one children with hypercholesterolemia (mean age 9.28 +/- 0.5 years) and 40 children with normocholesterolemia (mean age 9.02 +/- 0.69 years) were matched for gender and age. Within each group, children were classified as having or not having a family history of cardiovascular disease. Serum levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), a marker of oxidative stress, and plasma levels of soluble CD40L (sCD40L) were measured in each child. In a subgroup of children with high (n = 8) or normal (n = 8) levels of serum cholesterol, platelet p38 mitogen-activated protein (MAP) kinase phosphorylation, a protein involved in the activation of nicotinamide adenine dinucleotide phosphate oxidase, was determined. RESULTS: Children with hypercholesterolemia had higher values of 8-OHdG and sCD40L compared with control subjects (0.55 +/- 0.06 ng/ml vs. 0.21 +/- 0.02 ng/ml, p < 0.001 and 0.55 +/- 0.04 ng/ml vs. 0.19 +/- 0.03 ng/ml, p < 0.001, respectively). A significant correlation between 8-OHdG and sCD40L was observed in children with high (r = 0.676, p < 0.001) or normal (r = 0.878, p < 0.001) levels of cholesterol. Children with a family history of cardiovascular disease tended to have higher values of 8-OHdG and sCD40L, but the difference was not significant. Analysis of platelet p38 MAP kinase showed that it was phosphorylated more in children with hypercholesterolemia compared with control subjects (36.8 +/- 5.8 AU vs. 8.0 +/- 4.5 AU, p < 0.001 respectively). CONCLUSIONS: Children with hypercholesterolemia have an early increase of oxidative stress that may be responsible for up-regulation of CD40L and potentially predispose to premature atherosclerosis.