Glutamine-supplemented total parenteral nutrition improves immunological status in anorectic patients.

OBJECTIVE: Glutamine is an important substrate for critical cells of the immune system, in particular lymphocytes and macrophages, and it is considered a conditionally essential amino acid. Several studies have indicated that glutamine-enriched total parenteral nutrition improves immunologic status and shortens length of stay of critically ill patients. We investigated the effect of total parenteral nutrition supplemented with glutamine on the immune system in anorectic patients. METHODS: Thirty-six anorectic patients were randomized to receive standard parenteral nutrition or parenteral nutrition supplemented with glutamine 0.18 g kg(-1) d(-1) for 20 d. To evaluate the immune system status, we determined serum levels of neopterin and insulin growth factor-1 and lymphocyte count at baseline and after 10 and 20 d from the beginning of the therapy. RESULTS AND CONCLUSIONS: The results showed a significant increase of the serum levels of neopterin after 10 d of treatment with glutamine (26.44 +/- 3.08 versus 6.75 +/- 1.73 nmol/L, P < 0.001), thus proving a probable stimulating action carried out by glutamine on the immune system, as testified by the increase of lymphocytes.

Endothelial progenitor cells: pathogenetic role and therapeutic perspectives.

Bone marrow-derived, CD34+ progenitor cells have been shown to promote the repair of damaged tissues, offering promise for the treatment of hereditary and acquired human diseases. These cells in fact differentiate into endothelia, hematopoietic cells and possibly neurons, fibroblasts and muscle. CD34+ and AC133+ progenitor cells may participate in neovascularization by differentiating into endothelial cells. Circulating bone marrow-derived endothelial cells home to sites of neovascularization and stimulate healing of injured tissues but also promote restenosis, tumor growth and inflammatory disease. These cells may thus participate in tissue regeneration or pathogenesis of several diseases. Although the molecular mechanisms that promote the homing and recruitment of bone marrow-derived progenitor cells to remodeling tissues remain unclear the evidence that these cells promote tissue repair is strong.

Neurobiological model and quality of life in discovering personality of the uremic patient.

The Short Form-36 Health Survey (SF-36) questionnaire is designed to measure the patient's functional capacity and well-being. It was created to reach a compromise between lengthy investigation methods and one dimensional, overly simple tools for measuring quality of life (QoL). In 1987, the psychiatrist Robert Cloninger proposed a psycho-biological model hinged upon three principal and independent dimensions of the human personality: novelty seeking (NS), harm avoidance (HA) and reward dependence (RD), linked with dopaminergic, serotoninergic and noradrenergic activity, respectively. According to Cloninger, each dimension is the expression of the integration of a hereditary condition, characterized by biologic substrates, in response to specific environmental stimuli. We furthermore searched for any interference between the SF-36 scores and plasmatic dopamine, serotonin and noradrenaline concentrations, in an attempt to identify eventual correlations between the condition of the patients, their subjective QoL evaluation and neurohormonal plasmatic equilibrium. We compared results obtained from healthy subjects with populations of patients in different periods of their clinical existence: patients on hemodialysis; with a functioning transplantation; with renal graft function loss; returning to dialysis after graft loss and two years after restarting hemodialysis.

Statins in the prevention of cardiovascular events in patients with renal failure.

HMG-CoA reductase inhibitors (statins) are among the most widely used hypolypemizing drugs with a pleiotropic activity. Numerous clinical trials have demonstrated that statins can have a significant effect in the prevention of cardiovascular diseases in the general population. In patients with renal failure, this drug preserves the hypolypemizing efficacy found in the general population without increasing their unwanted side-effects. The re-analysis of data from epidemiological studies conducted on the general population has confirmed that statins provide cardiovascular protection also in subjects with renal failure. These data have been partly confirmed by the findings made by 4D (Die Deutsche Diabetes Dialyse Studie) and Alert studies, conducted on diabetic patients on dialysis and patients with renal transplants, respectively. The results of other studies, such as AURORA, SHARP, REnal and Vascular End stage Disease, and ESPLANADE, clearly indicate that statins prevent cardiovascular disease in patients with renal insufficiency, just as they do in the general population.

Correlation between quality of life assessment and a personality neurobiologic model in dialyzed patients.

The Short Form 36 Health Survey (SF-36) is a self-administered scoring system that has been widely used and validated as a quality of life (QOL) assessment tool. In our study, a cluster analysis of SF-36 scores was performed in 50 healthy volunteers (controls) and 50 neurobiologically asymptomatic patients on maintenance hemodialysis (MHD). Firstly, we assayed the tendency to form clusters from each of the investigated dimensions. Statistic analysis was performed using the Student's t-test for independent measurements and multiple regression analysis. Secondly, we attempted to evaluate if the MHD to apply to both groups a general psychobiological personality model developed by Cloninger in 1987. Cloninger describes three independent personality dimensions: novelty seeking (NS), harm avoidance (HA)and reward dependence (RD). Each personality dimension would be the expression of hereditary variations integrating the three main brain systems, respectively: dopaminergic, serotoninergic and noradrenergic. Finally, we then aimed to investigate possible interferences among the seric concentrations of the neuromodulators and SF-36 scores, in the attempt to identify, using a simple approach, the complex personality structure of MHD patients. QOL self-assessment and seric neuromodulators were measured in both groups, choosing an interdialytic day for MHD patients. We found that MHD patients perceived a significant worsening in their QOL in all investigated dimensions with respect to the controls. In addition, they showed significantly lower dopamine and serotonine concentrations and significantly higher noradrenaline concentrations. Therefore, our study, confirmed data reported previously in the literature, that cluster analysis of SF-36 scores provides different results in the MHD population in comparison to normal subjects. In fact, comparing the hierarchical trees of both groups, it appeared evident that in MHD patients, cluster dimensions were greater than in the controls. In cluster compositions showed differences between the two groups. In fact, in MHD patients there were only a few of the clusters that were observed in the controls (mental health and social functioning, vitality and general health), while role-physical and role-emotional dimensions aligned outside the hierarchical tree, with a considerable linkage distance. In our opinion, it is fascinating that the three Cloninger neuromodulators could suggest that HD patient personalities are potentially cyclothymiac, altering the disposition of the two role functions inside the hierarchical tree.