Biomedical subjects

Silvia Regina Manfredi

Publications and source records attributed to Silvia Regina Manfredi.

3 recordsLinked to original sources

PubMed2006

Effect of microcystin on leukocyte viability and function.

Microcystin (MC) has been found in several areas of the world. In addition to its hepatotoxicity, microcystin may have an immunomodulatory effect. Considering that patients receiving hemodialysis may be chronically exposed to variable concentrations of MC, and that they present important changes in this immune response, we have assessed the effect of MC on the function of leukocytes. Polymorphonuclear leukocytes isolated from healthy volunteers (HV) and patients receiving hemodialysis (HD) were incubated with microcystin (10 microg/L) for 24h and evaluated for reactive oxygen species production (ROS), phagocytosis and apoptosis. Monocytes incubated with and without LPS (100 ng/mL) and microcystin for 24h were assessed for TNFalpha and IL-10 production. Leukocytes of HV presented an increase in apoptosis rates and leukocytes from HD exhibited a lower production of oxygen-reactive species, both spontaneously and after stimulus with S. aureus, when compared with leukocytes incubated without toxin. Monocytes presented an increase in cytokine production after stimulation by LPS in both groups, but there was no difference between the groups with and without MC that were incubated with or without LPS. Low concentrations of microcystin can induce mild changes in leukocyte function of HV and HDP, particularly in the ability to produce ROS.

Apoptosis↗

PubMed2006

Nutritional parameters and mortality in incident hemodialysis patients.

OBJECTIVE: To evaluate the impact of nutritional parameters at the time of initiation of hemodialysis (HD) on mortality. DESIGN: Retrospective study. SETTING: Dialysis Unit of the Federal University of Sao Paulo, Oswaldo Ramos Foundation. PATIENTS: Three hundred forty-four incident HD patients (60.5% male, 26% diabetic) with the first nutritional evaluation performed before completing 3 months of onset of HD were included. METHODS: The study consisted of baseline measurements of several nutritional parameters (triceps skinfold thickness [TSF], midarm muscle circumference [MAMC], body mass index [BMI], serum albumin, serum creatinine, and protein and energy intake assessed by 3-day food diary) and records of outcome (death) over a period of 10 years. RESULTS: Muscle and/or fat depletion was observed in 51% of the studied patients, according to the percent standard of MAMC and TSF, respectively. Presence of diabetes, age over 60 years, serum albumin < 3.5 g/dL, MAMC adequacy < 90%, protein intake < 1.0 g/kg/d, and energy intake < 25 kcal/kg/d were associated with worse survival. When patients were analyzed according to tertiles of dialysis vintage, BMI > or = 25 (calculated as kg/m2) had a negative impact on survival only in the highest tertile (> 2.45 years). Patients with BMI < 25 and MAMC adequacy > or = 90% showed the best survival over the study period, and those with BMI > or = 25 but MAMC adequacy < 90% had the worst survival (P = .004). In the multivariate survival analysis adjusting for diabetes, advanced age, and hypoalbuminemia, the reduced MAMC (P = .008) and the low energy intake (P = .03) were independent predictors of death in incident HD patients. CONCLUSIONS: Reduced MAMC and low energy intake at the beginning of chronic dialysis are risk factors for mortality. A negative effect of high BMI on survival was associated with reduced MAMC and longer dialysis vintage.

Adipose Tissue↗

PubMed2003

A model for improving quality in nephrology settings.

Continuous quality improvement (CQI) programs have been instituted in many health care organizations over the last decade. PDCA, a tool composed of planning (P), doing (D), checking (C), and acting (A), has proved to be very useful in the CQI problem-solving process. The use of the PDCA tool described in this article resulted in the successful resolution of a hepatitis B outbreak in a Brazilian hemodialysis population and can serve as a model methodology for improving care in nephrology settings.

Brazil↗