The evaluation of preoperative and postoperative fetuin-A levels in patients with primary hyperparathyroidism.

OBJECTIVES: Our objective was to evaluate preoperative and postoperative serum fetuin-A levels in female patients with primary hyperparathyroidism (PHPT) and search for the relationship with parathyroid hormone (PTH) and vitamin D (25OHD). Although a role for fetuin-A is suggested in regulating bone mineralization, its function has not been completely defined. MATERIALS AND METHODS: In this cross-sectional study, 43 female patients with PHPT and 30 healthy women were recruited as the control group. We evaluated 73 women because we had only women patients with PHPT. Of the 43 patients, 10 symptomatic and 23 asymptomatic patients were surgically treated, whereas 10 patients were not operated. In all 43 patients, 25OHD, PTH, fetuin-A levels, and bone mineral densitometry were evaluated. The biochemical parameters of 33 operated patients were reevaluated at the postoperative sixth week. RESULTS: Fetuin-A levels of the patients with PHPT were significantly higher than that in the controls (56.6 ± 13.8 vs. 42.6 ± 20.7 ng/mL; P = 0.010). Fetuin-A levels of the operated patients were higher than nonoperated group. Furthermore, serum fetuin-A levels of the nonoperated patients were not different from those of controls. After parathyroidectomy, fetuin-A (41.5 ± 25.2 vs. 56.4 ± 13.7 ng/mL; P = 0.003), PTH [80.0 (51.5-137.5) vs. 211.0 (151.5-278.5) pg/mL; P < 0.001], and calcium (9.2 ± 0.7 vs. 10.7 ± 0.8 mg/dL; P < 0.001) values were found to be decreased significantly. CONCLUSION: In this study, fetuin-A levels of patients with PHPT were higher than those of the controls and significantly decreased after parathyroidectomy compared with the preoperative levels. Fetuin-A levels could be a beneficial marker to determine the changes in bone metabolism of the patients with PHPT and to detect the patients suitable for surgery.

Melatonin: a hepatoprotective agent against radioiodine toxicity in rats.

OBJECTIVES: The aim of the current study was to investigate the possible radioprotective effects of melatonin against hepatic radioiodine (RAI) toxicity. METHODS: Thirty-six rats were randomly divided into three groups: untreated control (Group 1); oral radioiodine (RAI, 111 MBq) administrated rats (Group 2), and melatonin group (oral RAI and daily intraperitoneal injection of 12 mg/kg melatonin-Group 3). In the third group, melatonin administration was started two days before and continued for five days after RAI administration. Twenty-four hours after the administration of the last dose of melatonin, liver samples were taken for biochemical and histopathological evaluation. RESULTS: Oxidative stress parameters demonstrated that melatonin treatment decreased the tissue malondialdehyde (MDA), advanced the oxidation protein products (AOPP) levels, and increased the total-SH (sulphydryl) levels when compared with RAI group. The differences were statistically significant between these groups for all parameters (p < 0.05). The histopathological damage in the melatonin-treated group was significantly less than the damage in RAI group (p < 0.05 for all pathological parameters). CONCLUSION: The results of this study demonstrated that melatonin reduced the harmful effects of RAI treatment on the liver. Anti-inflammatory and antioxidant activities are likely to be involved in the mechanism underlying the radio-protective effects of melatonin (Tab. 3, Fig. 1, Ref. 30).

Ultrastructural investigation of the protective effects of propolis on bleomycin induced pulmonary fibrosis.

We investigated the antioxidant and anti-inflammatory effects of propolis on bleomycin induced lung fibrosis and compared these effects to prednisolone treatment. Forty rats were divided into four groups of ten: group 1 was treated with intratracheal infusion of 0.2 ml physiological saline followed by daily treatment with 0.5 ml physiological saline for 20 days. In the remaining groups (groups 2 - 4), 5 mg/kg bleomycin was given via the trachea. Rats in group 2 were given 0.5 ml physiological saline. Rats in group 3 were treated with 100 mg/kg propolis, and 10 mg/kg prednisolone was given to rats in group 4. The treatments for all groups were continued for 20 days. On postoperative day 21, blood and lung samples were taken for biochemistry, histopathology and electron microscopy evaluation. We compared oxidative stress parameters and found lower malondialdehyde and myeloperoxidase levels, and higher total sulfhydryl levels and catalase activities for the bleomycin + propolis group than for the bleomycin and bleomycin + prednisolone groups. The highest mean fibrosis score was detected in the bleomycin group. Although the mean fibrosis scores of the bleomycin + propolis and bleomycin + prednisolone groups were not significantly different, electron microscopy revealed that propolis diminished bleomycin induced lung fibrosis more effectively than prednisolone. The effects of propolis might be due to its potent antioxidant and anti-inflammatory properties.

Effect of novel vitamin D receptor activator paricalcitol on renal ischaemia/reperfusion injury in rats.

INTRODUCTION: Despite the developments in modern medicine, acute renal injury is still a challenging and common health problem. It is well known that ischaemia and reperfusion takes place in pathological mechanisms. Efforts to clarify the pathophysiology and interventions to improve outcomes are essential. Our study aimed to investigate whether the prophylactic use of paricalcitol is beneficial in renal ischaemia/reperfusion (I/R) injury. METHODS: Twenty-four Wistar albino rats were assigned randomly to four groups. Right nephrectomies were performed at the time of renal arterial clamping. Sham surgery was performed on the rats in group 1. For the rats in group 2, the left renal artery was clamped for 45 minutes. The rats in group 3 received paricalcitol for seven days (0.2µg/kg/day); following this, a right nephrectomy and left renal arterial clamping were not performed. The rats in group 4 received paricalcitol for seven days (0.2µg/kg/day); following this, a right nephrectomy and left renal arterial clamping for 45 minutes were performed. Tissue thiobarbituric acid reactive substances (TBARS), superoxide dismutase, sulfhydryl groups as well as nitric oxide metabolites, serum urea and creatinine levels were measured for all four groups. RESULTS: In group 4, there were some improvements in terms of TBARS, nitrite, nitrate, superoxide dismutase and creatinine levels. In the histopathological evaluation, paricalcitol therapy improved tubular necrosis and medullar congestion but there was no significant difference in terms of tubular cell swelling, cellular vacuolisation or general damage. Immunohistopathological examination revealed lower scores for vascular endothelial growth factor in the group 4 rats than in group 2. CONCLUSIONS: Paricalcitol therapy improved renal I/R injury in terms of serum and histopathological parameters. These potential beneficial effects need to be further investigated.

Increased H-FABP concentrations in nonalcoholic fatty liver disease. Possible marker for subclinical myocardial damage and subclinical atherosclerosis.

AIM: Nonalcoholic fatty liver disease (NAFLD) is the most common liver disorder which is reported as the hepatic manifestation of metabolic syndrome with an increased risk of cardiovascular events. Patients with NAFLD are also at risk of future cardiac events independently of metabolic syndrome. The aim of this study was to examine serum concentrations of heart type fatty acid binding protein (H-FABP) in NAFLD and to investigate its correlations with metabolic parameters and subclinical atherosclerosis. PATIENTS AND METHODS: A total of 34 patients with NAFLD and 35 healthy subjects were enrolled in the study. NAFLD patients had elevated liver enzymes and steatosis graded on ultrasonography. Healthy subjects had normal liver enzymes and no steatosis on ultrasonography. H-FABP levels were measured using an enzyme linked immunosorbent assay (ELISA) method and correlations with metabolic parameters and subclinical atherosclerosis were examined. Subclinical atherosclerosis was determined with carotid artery intima-media thickness (CIMT) which was measured by high resolution B mode ultrasonography. RESULTS: H-FABP levels were elevated in patients with NAFLD (16.3 ± 4.0 ng/ml) when compared with healthy controls (13.8 ± 2.1 ng/ml; p < 0.001). NAFLD patients had significantly higher CIMT than the controls had (0.64 ± 0.17 mm vs. 0.43 ± 0.14 mm, p = 0.009). The H-FABP concentrations were significantly positively correlated with body mass index (r = 0.255, p = 0.042), fasting blood glucose level (r = 0.300, p = 0.013), CIMT (r = 0.335, p = 0.043), and homeostasis model assessment-estimated insulin resistance (HOMA-IR; r = 0.156, p = 0.306). In multiple linear regression analysis, H-FABP levels were only independently associated with CIMT (p = 0.04) CONCLUSION: Serum H-FABP concentrations increase in patients with NAFLD. Our results may not only suggest that H-FABP is a marker of subclinical myocardial damage in patients with NAFLD but also of subclinical atherosclerosis, independent of metabolic syndrome and cardiac risk factors.

Cardiovascular risk factors in hemodialysis and peritoneal dialysis patients.

BACKGROUND: Cardiovascular disease (CVD) is the major cause of mortality and morbidity of hemodialysis (HD) and peritoneal dialysis (CAPD) patients. We aimed to investigate the cardiovascular risk factors and their correlation with CVD in groups of HD and CAPD patients. METHODS: Thirty HD patients, 30 CAPD patients and 30 healthy controls were included in the study. Apolipoprotein A-l (apo A-l), apolipoprotein B (apo B), apolipoprotein(a) [Lp(a)] and high-sensitivity CRP (hs-CRP) were measured with a Beckman Coulter nephelometer, and homocysteine (Hcy) was determined with an Agilent HPLC analyzer. Lipid profile was determined with a Synchron LX 20 Pro analyzer. RESULTS: Hcy levels were 41.9+/-19.4, 41.8+/-38.5 and 9.3+/-3.5 micromol/L; Lp(a) levels were 325+/-315, 431+/-367 and 130+/-97 mg/L; hs-CRP levels were 3.78+/-3.21, 4.34+/-3.39 and 2.07+/-1.67 mg/L; apo A1/apo B ratios were 1.46+/-0.6, 1.36+/-0.5 and 1.80+/-0.59; total cholesterol levels were 3.56+/-0.7, 4.84+/-1.1 and 4.39+/-0.5 mmol/L; triglycerides were 1.44+/-0.5, 1.60+/-0.8 and 0.85+/-0.5 mmol/L in the HD, CAPD and control groups, respectively. CONCLUSION: HD and CAPD patients had higher Hcy, hs-CRP and Lp(a) levels and lower apo A/B ratios than controls. There was no significant difference between the HD and CAPD groups. Hypertension, age and hs-CRP showed a positive correlation with CVD.

Evidence of increased oxidative stress by simple measurements in patients with dilated cardiomyopathy.

The heart cannot supply sufficient blood for tissue metabolic needs in patients with congestive heart failure. Hypoxia and organ hypoperfusion increase oxidative activity. It has been reported that free radicals are involved in the genesis of heart failure. The aim of this study was to assess the status of oxidative stress by simple measurements in patients with dilated cardiomyopathy of ischemic or idiopathic etiology. Eleven patients (8 M, 3 F, age range 32 to 65 years) with dilated cardiomyopathy of ischemic etiology and 12 patients (8 M, 4 F, age range 31 to 66 years) with dilated cardiomyopathy of idiopathic etiology were included in the study. A control group included 21 healthy subjects (12 M, 9 F, age range 25 to 67 years). Levels of thiobarbituric acid-reactive substances, total thiols, and fluorescent products of lipid peroxidation were measured in plasma/serum samples of patients and controls. No statistically significant differences were found between the two patient groups for the parameters studied (p>0.05). Levels of thiobarbituric acid-reactive substances and fluorescent products of lipid peroxidation were higher in both patient groups than in controls (p<0.05), whereas concentrations of total thiols were decreased (p<0.05). In conclusion, in patients with idiopathic or ischemic dilated cardiomyopathy, there are associated abnormalities of a range of markers of increased oxidative stress and lipid peroxidation. The plasma/serum constituents studied can be routinely measured in order to monitor patients during antioxidant therapy.

Optically driven spin memory in n-doped InAs-GaAs quantum dots.

We show that the spin state of the resident electron in an n-doped self-assembled InAs-GaAs quantum dot can be written and read using nonresonant, circularly polarized optical pumping. A simple theoretical model is presented and accounts for the remarkable dynamics producing counterpolarized photoluminescence.

Increased oxidative stress in dilated cardiomyopathic heart failure.

In the present study, we assessed oxidative stress in patients with dilated cardiomyopathy of ischemic or idiopathic etiology. For this reason we measured whole blood reduced glutathione, erythrocyte superoxide dismutase, susceptibility of erythrocyte membranes and erythrocytes to peroxidation, and SH content of erythrocyte membranes in 12 patients (8 men and 4 women, ages 31 to 66 years) with idiopathic dilated cardiomyopathy, in 11 patients (8 men and 3 women, ages 32 to 65 years) with ischemic dilated cardiomyopathy, and in 21 healthy volunteers (12 men and 9 women, ages 25 to 67 years). There was no statistically significant difference between the two patient groups for the indicators studied (P >0.05). Blood glutathione, erythrocyte superoxide dismutase, and membrane SH content of both groups of patients was decreased compared with controls (P <0.05), whereas erythrocyte and membrane susceptibility to peroxidation were increased (P <0.05). We conclude that patients with idiopathic or ischemic dilated cardiomyopathy exhibit abnormalities of a range of markers of increased oxidative stress. These abnormalities may contribute to contractile dysfunction, increased incidence of fatal arrhythmias, and sudden death.