RESUMO
Robot-actuated mechanical loading (ML)-based therapies ("mechanotherapies") can promote regeneration after severe skeletal muscle injury, but the effectiveness of such approaches during aging is unknown and may be influenced by age-associated decline in the healing capacity of skeletal muscle. To address this knowledge gap, this work used a noninvasive, load-controlled robotic device to impose highly defined tissue stresses to evaluate the age dependence of ML on muscle repair after injury. The response of injured muscle to robot-actuated cyclic compressive loading was found to be age sensitive, revealing not only a lack of reparative benefit of ML on injured aged muscles but also exacerbation of tissue inflammation. ML alone also disrupted the normal regenerative processes of aged muscle stem cells. However, these negative effects could be reversed by introducing anti-inflammatory therapy alongside ML application, leading to enhanced skeletal muscle regeneration even in aged mice.
Assuntos
Regeneração , Robótica , Animais , Camundongos , Regeneração/fisiologia , Músculo Esquelético/fisiologia , Anti-InflamatóriosRESUMO
The international community is coming to the realization that in Third World countries the aging population is not a burden but a resource to aid society in many ways. In the Dominican Republic one program has tapped elders' resources to fill a need otherwise left gaping.
Assuntos
Idoso , Países em Desenvolvimento , Relação entre Gerações , Política Pública , República Dominicana , Humanos , Poder Psicológico , Nações UnidasRESUMO
Pathologic findings in biopsied rectus femoris muscle underlying an area of linear scleroderma are described. The affected muscle was weak and atrophic. On electromyography it showed motor unit potentials of decreased amplitude and duration. Light microscopic changes were minimal. There was atrophy of some histochemical type I fibers. More prominent changes were found at the ultrastructural level, where many of the capillary basal laminae were thickened and reduplicated. Most striking was the presence of two types of electron-dense, rounded inclusions within the mitochondria, one ranging from 29 to 47nm in diameter and the other from 54 to 131 nm in diameter.