Relation of physical activity, cardiac function, exercise capacity, and quality of life in patients with a systemic right ventricle

Exercise is recommended in patients with left ventricular failure. Although right ventricular failure is common in patients with a systemic right ventricle (RV), no data are available on the effect of physical activity in these patients. The aim of this study was to evaluate the relation of physical activity and cardiac function, exercise capacity, and quality of life in patients with a systemic RV. Forty-seven patients (64% men, mean age 35 years, range 21 to 69) with a systemic RV (31 with an atrially switched transposition of the great arteries and 16 with a congenitally corrected transposition of the great arteries) were included. Cardiac function was assessed by cardiovascular magnetic resonance or computed tomography, exercise tests, and serum N-terminal prohormone brain natriuretic peptide (NT-pro-BNP) levels. Habitual physical activity was assessed using the Short Questionnaire to Assess Health-Enhancing Physical Activity (SQUASH) and quality of life using the Medical Outcomes Study Short Form 36-Item Health Survey. Mean systemic right ventricular ejection fraction was impaired (36.8 +/- 7.8%), as was maximal exercise capacity (78.5 +/- 23.9% of predicted). NT-pro-BNP level was increased (median 269 ng/L, range 34 to 4,476). Mean SQUASH score was 6,808 +/- 3,241, indicating a decreased level of habitual physical activity. Although patients' scores on mental quality-of-life domains were comparable to the general population, scores on most physical quality-of-life domains were significantly lower. SQUASH scores were found to be a significant predictor for exercise capacity (p <0.01) and physical quality of life (p <0.001). However, we found no relation between SQUASH scores and right ventricular ejection fraction or NT-pro-BNP. In conclusion, physical activity in patients with a systemic RV is positively associated with exercise capacity and quality of life, irrespective of cardiac performance.     

Heritability of blood concentrations of sex-steroids in relation to body composition in young adult male siblings

Objective Sex steroid concentrations in men are related to body composition and both are determined by genetic and environmental factors. This study investigates heritability estimates of sex steroid serum concentrations and body composition as well as the genetic and environmental components of their interrelation. Patients Six hundred and seventy‐four men (25–45 years) were included in this study with 274 independent pairs of brothers. Measurements Body composition and regional fat mass estimates were determined using dual‐energy X‐ray absorptiometry. Serum testosterone (T), SHBG, oestradiol (E₂) and LH levels were determined by immunoassay; free T and E₂ levels were calculated. Results Both sex steroid hormone concentrations and indices of body composition exhibited significant heritability estimates. Among sex steroid hormones, T had the highest heritability (h² = 0·65), followed by free T (h² = 0·54). A heritability of 0·73 was observed for SHBG; a heritability estimate of 0·83 was obtained for body weight. Significant genetic correlations were found between whole body fat mass and serum T (ρ_G = –0·46), free T (ρ_G = –0·27) and SHBG (ρ_G = –0·48) concentrations. No genetic relationship was observed between total (F) E₂ or LH concentrations, respectively, and body composition. Conclusion Both sex steroid serum levels and body composition are under strong genetic control. Their interrelation is in part underlied by a genetic correlation, indicative of the action of shared genes.     

Morphine differentially affects the sensory and affective pain ratings in neurogenic and idiopathic forms of pain.

In a double-blind, placebo controlled crossover study, the effect of morphine on the affective and sensory pain ratings in different forms of chronic pain was investigated. Six patients suffering from central neurogenic pain, 8 from peripheral neurogenic pain and 6 from idiopathic pain participated in the study. Morphine (0.3 mg/kg bodyweight) and placebo (saline) were administered intravenously. Both the affective and sensory dimensions of pain sensation were assessed by means of the 101-point rating scale. From our results it appeared that morphine reduced the affective but not the sensory dimension of pain sensation in both groups of neurogenic pain patients. In the idiopathic pain group, neither the affective nor the sensory dimension of pain sensation were affected. The observed differences in opioid responsiveness were neither the result of differences in opioid consumption nor of differences in baseline pain levels.     

Health-related quality of life in end-stage renal disease patients: the effects of starting dialysis in the first year after the transition period

Background/aims

Prevalent dialysis patients have low scores of health-related quality of life (HRQOL) which are associated with increased risk of hospitalization and mortality. Also in CKD-5 non-dialysis patients, HRQOL scores seem to be lower as compared with the general population. This study firstly aimed to compare HRQOL between CKD-5 non-dialysis and prevalent dialysis patients in a cross-sectional analysis and to assess longitudinal changes over 1 year after the dialysis initiation. Secondly, the correlation between HRQOL and physical activity (PA) was explored.

Methods

Cross-sectional 44 CKD-5 non-dialysis, 29 prevalent dialysis, and 20 healthy controls were included. HRQOL was measured by Short Form-36 questionnaires to measure physical and mental domains of health expressed by the physical component summary (PCS) and mental component summary (MCS) scores. PA was measured by a SenseWear? pro3. Longitudinally, HRQOL was assessed in 38 CKD-5 non-dialysis patients (who were also part of the cross-sectional analysis), before dialysis initiation until 1 year after dialysis initiation.

Results

PCS scores were significantly lower both in CKD-5 non-dialysis patients and in prevalent dialysis patients as compared with healthy controls (p?<?0.001). MCS scores were significantly lower in both CKD-5 non-dialysis patients (p?=?0.003), and in dialysis patients (p?=?0.022), as compared with healthy controls. HRQOL scores did not change significantly from the CKD-5 non-dialysis phase into the first year after dialysis initiation. PA was significantly related to PCS in both CKD-5 non-dialysis patients (r?=?0.580; p?<?0.001), and dialysis patients (r?=?0.476; p?=?0.009).

Conclusions

HRQOL is already low in the CKD-5 non-dialysis phase. In the first year after dialysis initiation, HRQOL did not change significantly. Given the correlation between PCS score and PA, physical activity programs may be potential tools to improve HRQOL in both CKD-5 non-dialysis as well as in prevalent dialysis patients.

     

Radiation-induced Lipid Peroxidation: Influence of Oxygen Concentration and Membrane Lipid Composition

Summary

Radiation-induced lipid peroxidation in phospholipid liposomes was investigated in terms of its dependence on lipid composition and oxygen concentration. Non-peroxidizable lipid incorporated in the liposomes reduced the rate of peroxidation of the peroxidizable phospholipid acyl chains, possibly by restricting the length of chain reactions. The latter effect is believed to be caused by interference of the non-peroxidizable lipids in the bilayer. At low oxygen concentration lipid peroxidation was reduced. The cause of this limited peroxidation may be a reduced number of radical initiation reactions possibly involving oxygen-derived superoxide radicals. Killing of proliferating mammalian cells, irradiated at oxygen concentrations ranging from 0 to 100 per cent, appeared to be independent of the concentration of peroxidizable phospholipids in the cell membranes. This indicates that lipid peroxidation is not the determining process in radiation-induced reproductive cell death.     

Fluid state and blood pressure control: no differences between APD and CAPD

The aim of this study was to compare fluid state, ambulatory blood pressure, and sodium removal in automated peritoneal dialysis (APD) and continuous ambulatory peritoneal dialysis (CAPD). This observational, cross-sectional study comprised 20 APD and 24 CAPD patients with a mean duration on peritoneal dialysis of 30 ± 26 and 21 ± 23 months, respectively. Sixty-four percent of the patients were treated with icodextrin. The methods used were 24 hr dialysate and urine collections, standardized 3.86% glucose peritoneal equilibration test (PET), bioimpedance analysis, and 24 hr ambulatory blood pressure monitoring. Extracellular water (ECW) corrected for body weight was 0.23 6 0.03 L/kg both in APD and CAPD patients. The slope normovolemia value according to Chamney was 0.0 6 0.2 L/kg in APD patients and 0.0 6 0.05 L/kg in CAPD patients (not significant [NS]). Mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) were respectively, 132 ± 25 and 79 ± 8 mm Hg in APD and 129 ± 16 and 76 ± 11 mm Hg in CAPD patients (NS). Sodium concentration in dialysate was respectively, 129.5 ± 3.5 mmol/L in APD and 132.4 ± 4.1 mmol/L in CAPD (p= 0.017). Dialysate sodium removal was 80.6 ± 78.4 mmol/24 hr in APD and 108.7 ± 96.8 mmol/24 hr in CAPD patients (NS). Natriuresis was respectively, in APD 76.6 ± 65.5 mmol/24 hr and in CAPD 93.5 ± 61.7 mmol/24 hr (NS). Total sodium removal was 149.5 ± 76.6 mmol/24 hr in APD and 198.4 ± 75.0 mmol/24 hr in CAPD (p= .039). Despite a higher daily sodium removal in CAPD patients, fluid state and blood pressure were not different between APD and CAPD. In general, volume status and blood pressure appeared to be reasonably controlled in this unselected population.     

Intestinally secreted C-type lectin Reg3b attenuates salmonellosis but not listeriosis in mice

The Reg3 protein family, including the human member designated pancreatitis-associated protein (PAP), consists of secreted proteins that contain a C-type lectin domain involved in carbohydrate binding. They are expressed by intestinal epithelial cells. Colonization of germ-free mice and intestinal infection with pathogens increase the expression of Reg3g and Reg3b in the murine ileum. Reg3g is directly bactericidal for gram-positive bacteria, but the exact role of Reg3b in bacterial infections is unknown. To investigate the possible protective role of Reg3b in intestinal infection, Reg3b knockout (Reg3b(-/-)) mice and wild-type (WT) mice were orally infected with gram-negative Salmonella enteritidis or gram-positive Listeria monocytogenes. At day 2 after oral Listeria infection and at day 4 after oral Salmonella infection, mice were sacrificed to collect intestinal and other tissues for pathogen quantification. Protein expression of Reg3b and Reg3g was determined in intestinal mucosal scrapings of infected and noninfected mice. In addition, ex vivo binding of ileal mucosal Reg3b to Listeria and Salmonella was investigated. Whereas recovery of Salmonella or Listeria from feces of Reg3b(-/-) mice did not differ from that from feces of WT mice, significantly higher numbers of viable Salmonella, but not Listeria, bacteria were recovered from the colon, mesenteric lymph nodes, spleen, and liver of the Reg3b(-/-) mice than from those of WT mice. Mucosal Reg3b binds to both bacterial pathogens and may interfere with their mode of action. Reg3b plays a protective role against intestinal translocation of the gram-negative bacterium S. enteritidis in mice but not against the gram-positive bacterium L. monocytogenes.     

Candidate Gene Association Study for Noise-induced Hearing Loss in Two Independent Noise-exposed Populations

Millions of people are daily exposed to high levels of noise. Consequently, noise-induced hearing loss (NIHL) is one of the most important occupational health hazards worldwide. In this study, we performed an association study for NIHL based on a candidate gene approach. 644 Single Nucleotide Polymorphisms (SNPs) in 53 candidate genes were analyzed in two independent NIHL sample sets, a Swedish set and part of a Polish set. Eight SNPs with promising results were selected and analysed in the remaining part of the Polish samples. One SNP in PCDH15 (rs7095441), resulted in significant associations in both sample sets while two SNPs in MYH14 (rs667907 and rs588035), resulted in significant associations in the Polish sample set and significant interactions with noise exposure level in the Swedish sample set. Calculation of odds ratios revealed a significant association of rs588035 with NIHL in the Swedish high noise exposure level group. Our studies suggest that PCDH15 and MYH14 may be NIHL susceptibility genes, but further replication in independent sample sets is mandatory.