Sarcopenia: etiology, clinical consequences, intervention, and assessment

The aging process is associated with loss of muscle mass and strength and decline in physical functioning. The term sarcopenia is primarily defined as low level of muscle mass resulting from age-related muscle loss, but its definition is often broadened to include the underlying cellular processes involved in skeletal muscle loss as well as their clinical manifestations. The underlying cellular changes involve weakening of factors promoting muscle anabolism and increased expression of inflammatory factors and other agents which contribute to skeletal muscle catabolism. At the cellular level, these molecular processes are manifested in a loss of muscle fiber cross-sectional area, loss of innervation, and adaptive changes in the proportions of slow and fast motor units in muscle tissue. Ultimately, these alterations translate to bulk changes in muscle mass, strength, and function which lead to reduced physical performance, disability, increased risk of fall-related injury, and, often, frailty. In this review, we summarize current understanding of the mechanisms underlying sarcopenia and age-related changes in muscle tissue morphology and function. We also discuss the resulting long-term outcomes in terms of loss of function, which causes increased risk of musculoskeletal injuries and other morbidities, leading to frailty and loss of independence

Multiple disadvantage of older migrants and native Dutch older adults in deprived neighbourhoods in Amsterdam, the Netherlands: a life course perspective

It is commonly suggested that older non-Western migrants have a higher risk of experiencing multiple forms of disadvantage than native older adults. However, few researchers have studied the life situation and urban conditions of older migrants in relation to each other and in comparison to native older adults with a similar socioeconomic status. This paper investigates whether different groups of older non-Western migrants (of Surinamese, Moroccan and Turkish origin) in deprived neighbourhoods in Amsterdam experience similar or different levels of multiple disadvantage compared to socioeconomically similar native Dutch older residents living in the same neighbourhoods, and explores how multiple disadvantage can be explained in relation to life and residential histories and neighbourhood changes. Analysis of 85 in-depth interviews indicates that all categories of low-income older adults experienced certain levels of disadvantage, although they evaluated their circumstances using different frames of reference. Regarding health, both native-born and migrant older people experienced chronic illness. However, the results of this study suggest that those in the latter group (especially Moroccans and Turks) experienced health problems and related functional limitations at a younger age. Native Dutch older adults were somewhat better off with respect to the availability of household resources, but compared to older non-Western migrants were more likely to experience the negative effects of neighbourhood deprivation. In summary, this study refines common assertions that older migrants are more disadvantaged than native older adults. Differences in experiences of advantage and disadvantage have their origin in differences in life and residential histories and neighbourhood change

Cytokine responses and regulation of interferon-gamma release by human mononuclear cells to Aspergillus fumigatus and other filamentous fungi.

Contains fulltext : 48233.pdf (publisher's version ) (Closed access)There is substantial evidence that the production of proinflammatory cytokines is important in host resistance to invasive aspergillosis. Knowledge of the host response towards other filamentous fungi is scarce, as most studies have focused on Aspergillus fumigatus. In addition, interferon-gamma (IFNgamma) plays a crucial role in the control of invasive aspergillosis, but little is known about the regulation of IFNgamma after stimulation of mononuclear cells by A. fumigatus. Cytokine responses to four different Aspergillus spp., Scedosporium prolificans, and a Rhizopus oryzae strain were compared for their ability to induce the release of tumour necrosis factor-alpha (TNFalpha) and interleukin(IL)-6 by human monocytes. S. prolificans induced significantly more TNFalpha and IL-6 release compared to A. fumigatus, while the various Aspergillus spp. induce comparable levels of these cytokines. By using specific cytokine inhibitors we were able to show that endogenous IL-1, but not IL-18 and TNFalpha was required for IFNgamma and IL-10 release upon stimulation with A. fumigatus hyphae, whereas conidia induced IFNgamma stimulation is independent of these cytokines