Clinical and Seasonal Variations of Nutritional Risk Screening in Patients Scheduled for Rehabilitation after Heart Surgery

Background: Current knowledge on the pervasiveness of increased nutritional risk in cardiovascular diseases is limited. Our aim was to analyze the characteristics of nutritional risk screening in patients scheduled for rehabilitation after heart surgery. Prevalence and extent of nutritional risk were studied in connection with patients' characteristics and seasonal climate effects on weight loss dynamics. Methods: The cohort included 65 consecutive patients with an age range of 25-84 years, 2-6 months after surgical treatment for ischemic or valvular heart disease. Nutritional risk screening was appraised using a standardized NRS-2002 questionnaire. Groups were analyzed according to a timeline of rehabilitation according to the "cold" and "warm" seasons of the moderate Mediterranean climate in Opatija, Croatia. Results: Increased nutritional risk scores (NRS-2002) of >3 were found in 96% of studied patients. Mean NRS-2002 of patients was 5.0 +/- 1.0, with a percentage weight loss history of 11.7% +/- 2.2% (4.6-19.0). Risk was found to be more pronounced during the warmer season, with NRS-2002 scores of 5.3 +/- 0.7 versus 4.8 +/- 1.1 (P = 0.136) and greater loss of weight of 13.0% +/- 3.2% versus 10.6% +/- 3% (P = 0.005), respectively. Increased nutritional risk correlated significantly with creatinine concentrations (rho = 0.359; P = 0.034 versus 0.584; P = 0.001, respectively). Significant discordance in correlations was found between NRS-2002 and the decrease in left ventricle systolic function (rho correlation coefficient [rho-cc] = -0.428; P = 0.009), the increase in glucose concentrations (cc = 0.600; P < 0.001), and the decrease in erythrocyte counts (cc = -0.520; P = 0.001) during the colder season. Conclusion: Increased nutritional risk was found to be frequently expressed in the course of rehabilitation after heart surgery. Although seasonal climate effects influenced the weight loss dynamics, the impact on reproducibility of NRS-2002 was clinically less important. Further studies on the connection of nutritional risk with composited end points might offer improvements in overall quality of treatment

Influence of the interfacial peptide organization on the catalysis of hydrogen evolution.

The hydrogen evolution reaction is catalyzed by peptides and proteins adsorbed on electrode materials with high overpotentials for this reaction, such as mercury. The catalytic response characteristics are known to be very sensitive to the composition and structure of the investigated biomolecule, opening the way to the implementation of a label-free, reagentless electroanalytical method in protein analysis. Herein, it is shown using the model peptide Cys-Ala-Ala-Ala-Ala-Ala that the interfacial organization significantly influences the catalytic behavior. This peptide forms at the electrode two distinct films, depending on the concentration and accumulation time. The low-coverage film, composed of flat-lying molecules (area per molecule of approximately 250-290 A(2)), yields a well-defined catalytic peak at potentials around -1.75 V. The high-coverage film, made of upright-oriented peptides (area per molecule of approximately 43 A(2)), is catalytically more active and the peak is observed at potentials less negative by approximately 0.4 V. The higher activity, evidenced by constant-current chronopotentiometry and cyclic voltammetry, is attributed to an increase in the acid dissociation constant of the amino acid residues as a result of the low permittivity of the interfacial region, as inferred from impedance measurements. An analogy is made to the known differences in acidic-basic behaviors of solvent-exposed and hydrophobic domains of proteins.Journal ArticleResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe