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To test the hypotheses: (1) there is no difference in the volumetric wear among composites tested, and (2) there is no difference in the wear rates calculated from the linear relationship of wear increase over cycling. Methods: Two composites comprising pre-polymerized particles (Herculite-Précis [H], Tetric-N-Ceram [T]), one composite with very fine glass fillers (Charisma Opal [C]), and one composite with a mixture of agglomerated and nonagglomerated silica, and zirconia fillers (Filtek Z 350 XT [F]) were tested in a chewing simulator (CS 4.8, SD Mechatronik) with spherical Steatite antagonists (Ø 6 mm). Eight specimens of each composite were made by applying two increments in aluminum specimen-holders with a cylindrical cavity (Ø 8 mm, depth 1.5 mm), light cured (Bluephase G2; 1383 mW/cm2) for 20 s, polished to high gloss, and subjected to mastication cycles (59 N, 1.2 Hz, lateral movement 0.7 mm) and thermocycles (5/55°C; 116 s per cycle) simultaneously. After each 100,

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Introduction. Hyperparathyroidism can persist for many years in 10-50% of patients after successful kidney transplantation and can harmfully affect graft function and bone metabolism. Calcimimetic cinacalcet offers a new treatment option in hyperparathyroidism after kidney transplantation. It is a well established treatment in the dialysis population but data in kidney transplantation is still sparse, especially regarding its influence on bone mineral density. The aim of this study was to analyze the influence of cinacalcet on hyperparathyroidism, calcemia and bone mineral density in kidney transplant recipients. Methods. Eleven patients (4 men, 7 women, aged 39 to 64 years) were included in this prospective clinical study. The inclusion criteria were intact parathyroid hormone (iPTH) >65 nmol/l, serum creatinine concentration <150 μmol/l, stable kidney graft function and more than one year after kidney transplantation. Patients were not treated in the past and during the study with drugs that can have an impact on bone density (bisphosphonates, calcitonine). The study consisted of a 6 month observation period to certify the stability of measured parameters and a 12 month treatment period during which 30 mg/day of cinacalcet was used. Parameters of bone mineral metabolism (serum concentrations of calcium, phosphate, iPTH, 25-OHD3, osteocalcin, collagen degradation fragments, receptor activator of NF-kappa B ligand (RANKL), activity of bone specific alkaline phosphatase (AF), urinary calcium excretion) and bone mineral density (measured by double x-ray densitometry) were followed during the study. Results. During the observation period no measured parameter changed significantly. During the treatment period calcium concentration decreased significantly in the first month (m) of treatment and remained so during the whole study period (from 2.50±0.10 mmol/l at time 0 to 2.32±0.11 mmol/l at 12 m) (p<0.001). Serum iPTH decreased significantly in the first month of treatment (from 275±95 nmol/l to 202±56 nmol/l) but increased gradually thereafter. Concentration of serum phosphate, osteocalcin, RANKL and activity of AF did not change significantly during the treatment period. Collagen degradation fragments increased significantly during the treatment period (from 6186±3150 pmol/l at time 0 to 9455±7228 pmol/l at 12 m) (p<0.05). The concentration of 25-OH D3 was 51.7±21.7nmol/l and remained unchanged after 12 m. Urinary calcium/creatinine ratio was 0.27±0.23 at time 0 and did not changed significantly during the treatment period. Bone mineral density at lumbar spine, hip and forearm did not change during 12 m of cinacalcet treatment. Serum creatinine remained unchanged during the study period (107±45 μmol/l at time 0 and 115±62 μmol/l at 12 m). One patient stopped taking cinacalcet because of nausea and vomiting and was excluded from the analysis. Conclusions. Treatment with cinacalcet 30 mg/day in kidney transplant recipients resulted in a significant decrease of serum calcium concentration and a transient decrease of i...

Background and Aims Plasma N-terminal fragment of pro brain natriuretic peptide (NTproBNP) concentration is elevated in cardiovascular diseases such as congestive heart failure, where increased levels of NTproBNP indicate cardiac dysfunction, hypervolemia, and higher risk of hospitalization and death. These associations have also been studied in patients with chronic kidney disease (CKD), where NTproBNP value remains controversial, especially in long-term peritoneal dialysis (PD) patients with respect to its pathophysiologic implications. This study aim was to determine whether NTproBNP was a predictor of hospital admissions and cardiovascular events among patients on automated (APD) and continuous (CAPD) ambulatory peritoneal dialysis. Methods This was a cross-sectional study which included stable patients from two Peritoneal Dialysis Units. Plasma NTproBNP concentration was measured in stable adult peritoneal dialysis patients attending for routine assessments on PD outpatient clinic. In all patients, demographic variables, clinical and other laboratory parameters were recorded and analyzed. Descriptive statistics was performed. Groups were compared using independent t-test for comparison of continuous variables and Chi square test for categorical variables. In order to evaluate relationship between NTproBNP and the other variables multivariate logistic regression and Pearson bivariate analysis were used. Results The study enrolled 70 patients (male/female 44/26; mean age 55.3±14.6 years; APD/CAPD 25/45; PD duration 28±24.2months). One third (31.4%) of the patients was diabetic, 12.9% presented cardiac insufficiency and 20% had cardiovascular disease. Pearson bivariate correlation analysis revealed that patients with higher weekly kt/v (p=0.039), total fluid removal (diuresis and ultrafiltration) (p=0.027) and total weekly creatinine clearance (p=0.007) had lower NTproBNP values. These patients had also significant lower plasmatic creatinine and phosphorus levels. We found no significant association with residual kidney function, peritoneal transport (D/P creatinine), serum albumin levels and c-reactive protein. We also found that patients with higher NTproBNP levels had significantly more cardiovascular events (p=0.010) and a trend for more common hospital admissions (p=0.066). There were no significant differences regarding NTproBNP between the two modalities of peritoneal dialysis (APD and CAPD patients) or in patients who were PD first. As expected, patients with cardiac dysfunction had significant higher NTproBNP values (p=0.004). Diabetic patients had higher NTproBNP levels, althought this difference was not significant. Conclusion Despite the inconsistency in the NTproBNP value among long-term PD patients, results from most studies concur that NTproBNP levels are closely associated with left ventricular dysfunction, morbidity and mortality in these patients. In our study, patients with higher NTproBNP levels had more cardiovascular events and a trend for more common hospital admissions. Regular monitoring of NTproBNP levels among PD patients may be useful for providing care for these patients. Plus, NTproBNP was associated with better PD efficacy, greater fluid removal and higher creatinine clearance, reinforcing clinical relevance of PD optimization. These results require confirmation in a prospective study.

Background and Aims Sleep quality is an important and determining factor in the quality of life (QoL) during dialysis. The prevalence of sleep disorders in the general population varies between 10 and 40%; this figure increases to 50% in dialysis patients. This study was conducted to determine which factors influence sleep quality in end stage renal disease patients on automated (APD) and continuous (CAPD) ambulatory peritoneal dialysis. Methods This was a cross-sectional study which included stable patients from two Peritoneal Dialysis Units. We excluded patients who weren’t able to understand the questionnaires, the language and the ones who had hospitalar admissions in the previous 3 months. Pittsburg Sleep Quality Index (PSQI) was used for assessing sleep quality (the higher the score, the lower the sleep quality), while quality of life parameters were assessed by self-administered EuroQol questionnaire (EQ-5D-5L). The presence of depressive symptoms was made with Patient Health Questionnaire (PHQ-9). In all patients, demographic variables, Charlson Comorbidity Index (CCI), clinical and laboratory parameters were recorded and analyzed. Descriptive statistics was performed. Two groups were created according to Pittsburg Sleep Quality score: G1 (n=42) - “poor” sleep quality and G2 (n=28) - “good” sleep quality. Groups were compared using independent t-test for comparison of continuous variables and Chi square test for categorical variables. In order to evaluate relationship between sleep quality and the other variables multivariate logistic regression and Pearson bivariate analysis were used. Results The study enrolled 70 patients (male/female 44/26; mean age 55.3±14.6 years; APD/CAPD 25/45; PD duration 28±24.2months). One third (31.4%) of the patients was diabetic, 12.9% presented cardiac insufficiency and 20% had cardiovascular disease. 50% of our population had a sleep disorder, although the majority of the problems were slight to moderate. We found that PD patients who sleep better (G2) had significant better life quality (p&lt;0.001), lower CCI (p&lt;0.001) and were less depressed (p&lt;0.001). 77.3% of the patients with worst sleep quality (G1) were diabetic (p=0.04), regardless glycemic control and hemoglobin A1c. There were no significant differences between the two modalities of peritoneal dialysis (APD and CAPD patients), between genders or in patients who were PD first. We found no significant association between sleep quality and dialysis efficacy (weekly kt/v). Multivariate analysis (linear regression) showed a significant association between sleep quality and EuroQol (ExpB=0.000; IC 95% 0.000 to 0.054; p=0.002) and, depression (ExpB=1.274; IC 95% 1.045 to 1.552; p=0.017) in a model adjusted to age, PD duration and diabetes. Conclusion Our results show that poor sleep quality seems to be linked to life quality, comorbidity burden and depression. A better understanding of risk factors associated with poor sleep quality may help to signalize the patients who may benefit of specific treatment. The PSQI survey is a simple tool offering very complete information on sleep quality. The implementation of actions aimed at improving the hygiene of sleep may be an excellent way to improve the patients’ quality of life in an efficient and effective manner.