Impact of Nutritional Status on Muscle Architecture in Elerly Patients Hospitalized in Internal Medicine Wards.

Nutritional alterations are highly prevalent in older rather than adult hospitalized patients. In these subjects, a loss of physical performance is dependent on the impairment of muscle architecture. This study aimed to investigate the association between the nutritional status and muscle architecture in elderly patients hospitalized in internal medicine wards. 68 aged patients admitted in internal medicine wards were consecutively enrolled and stratified in three groups based on the Mini Nutritional Assessment (MNA) score: well-fed (WF), at risk of malnutrition (RM), and malnourished (M). Biochemical indices and anthropometric parameters were sampled at hospital admission. Furthermore, all patients were assessed at admission and after 7 days of hospitalization for muscle strength (hand-grip test), mass (bioimpedentiometry), and architecture (ultrasonography of vastus lateralis). At hospital admission, M patients showed lower percentage of fat free mass and muscle mass with respect to WF and RM. Furthermore, M group presented with lower muscle thickness and pennation angle, as compared to WF and RM. At admission, the MNA score was positively related to the pennation angle and muscle strength. Multivariate linear regression analysis showed that the nutritional status at admission was the only significant factor influencing pennation angle. Finally, during the first 7 days of hospitalization, a decrease of pennation angle occurred in all the groups studied. We conclude that malnutrition at admission is associated with impaired muscle architecture in elderly patients hospitalized in internal medicine wards. Moreover, muscle architecture is impacted by early hospitalization, irrespective of nutritional status.

The interaction between human monocytes and red cells. Binding characteristics.

Red cells coated with IgG globulin were bound firmly to human mononuclear cells and formed rosettes. Rosette formation occurred when red cells were coated with IgG attached either immunologically (anti-D, anti-penicillin, or Donath-Landsteiner antibodies) or nonimmunologically with chromic chloride; no attachment was observed with cells coated with albumin. Rosette formation was blocked by pretreatment of white cells with sulfhydryl-binding reagents. Metabolic inhibitors did not prevent red cell adherence. White cells of other primates demonstrated a high degree of species specificity. Ultrastructural studies showed that the predominant leukocytes involved in rosette formation were monocytes, but some cells with characteristics of lymphocytes also formed rosettes. Considerable interdigitation of cell surfaces occurred at attachment sites and bound red cells appeared deformed. Thus, these studies confirm the presence of specific surface receptors for IgG on human monocytes and suggest that such receptors may provide a mechanism by which large numbers of red cells are eventually destroyed.