The “Goldilocks Zoneâ€? from a redox perspectiveâ€â€�Adaptive vs. deleterious responses to oxidative stress in striated muscle

Consequences of oxidative stress may be beneficial or detrimental in physiological systems. An organ system's position on the “hormetic curve� is governed by the source and temporality of reactive oxygen species (ROS) production, proximity of ROS to moieties most susceptible to damage, and the capacity of the endogenous cellular ROS scavenging mechanisms. Most importantly, the resilience of the tissue (the capacity to recover from damage) is a decisive factor, and this is reflected in the disparate response to ROS in cardiac and skeletal muscle. In myocytes, a high oxidative capacity invariably results in a significant ROS burden which in homeostasis, is rapidly neutralized by the robust antioxidant network. The up-regulation of key pathways in the antioxidant network is a central component of the hormetic response to ROS. Despite such adaptations, persistent oxidative stress over an extended time-frame (e.g., months to years) inevitably leads to cumulative damages, maladaptation and ultimately the pathogenesis of chronic diseases. Indeed, persistent oxidative stress in heart and skeletal muscle has been repeatedly demonstrated to have causal roles in the etiology of heart disease and insulin resistance, respectively. Deciphering the mechanisms that underlie the divergence between adaptive and maladaptive responses to oxidative stress remains an active area of research for basic scientists and clinicians alike, as this would undoubtedly lead to novel therapeutic approaches. Here, we provide an overview of major types of ROS in striated muscle and the divergent adaptations that occur in response to them. Emphasis is placed on highlighting newly uncovered areas of research on this topic, with particular focus on the mitochondria, and the diverging roles that ROS play in muscle health (e.g., exercise or preconditioning) and disease (e.g., cardiomyopathy, ischemia, metabolic syndrome)

Patellofemoral pain syndrome assessed by Lysholm score, radiological and biorheometric measurements.

The aim of In this study was to verify the relationship among clinical indicators of patellofemoral pain syndrome (PFPS) and the results of modifying radiological investigation. Previous research suggests that there is a poor association between them. Therefore we have employed a technique for the functional evaluation of PFPS based on measuring the stiffness of the knee joint during passive flexion (biorheometry). The correlation between clinical examination and a standardized Lysholm score, radiological and biorheometric measures was investigated in the 28 knee joints of 14 subjects exhibiting clinical features of PFPS. A modified axial radiological projection of the patellofemoral articulation in 90° of flexion provided the parameters quantifying the anatomical - morphological arrangement of the patellofemoral joint. The biorheometric properties of the knee were evaluated using a custom made measuring apparatus during passive flexion and extension of the knee. Our results confirm that the link between the clinical findings and the X-ray imaging examinations was not evident. On the contrary, the biorheometric examination proved to correlate well with the clinical symptoms of PFPS. Parameters were identified which can characterize the biorheograms of people suffering PFPS. Analysis of the relationship among the clinical, radiological and biorheometric examinations leads to the recommendation that biorheometric examination is an effective method for the objective assessment of PFPS

Potential Implications of Climate Change for U.S. Agriculture

This report examines potential agronomic and economic effects of several assumed changedclimate scenarios on grain farming in the United States. The analysis is based on a protocol that links climatic, agronomic, and economic models to form an integrated model. Three assumed climate scenarios are investigated for their relative effects on crop yields, cropping patterns, and farm-level profitability. The climate scenarios are simulated for representative farms in Iowa, Illinois, Nebraska, Minnesota, Ohio, Georgia, and North Carolina. The agronomic results indicate that the mild climate scenario has little effect on crop yields and that farmers can effectively adapt to increasing temperatures and precipitation by selecting later maturing varieties. Corn and soybean yields are negatively affected at all sites in the more severe climatechange scenario. Northern States are less severely affected by both climate scenarios in terms of soybean yields. The economic results suggest crop prices are fairly sensitive to the rate and the form of the assumed climate-change scenario. Under the mild climate-change scenario, corn prices (inflation adjusted) increase and wheat prices decrease. Soybean prices increase, but at a lower rate than in the no climate-change case. In the more severe climate-change scenario, soybean and corn prices have the largest increase over time. Net farm revenue is lower under climate change than in the no climate-change case. However, there is little difference in net farm revenue between the mild and the severe climate-change scenarios