Relationship between arterial stiffness and myocardial damage in patients with newly diagnosed essential hypertension

BackgroundArterial stiffness increases in hypertensive individuals. Arterial stiffness is associated with impairment of systolic and diastolic myocardial function in hypertension (HT). However, the relationship between arterial stiffness and serum heart-type fatty acid-binding protein (H-FABP) levels, a sensitive marker of myocardial damage, has not been previously examined in patients with HT. We investigate the relationship between serum H-FABP levels and arterial stiffness in patients with newly diagnosed HT.MethodsWe studied 46 (48.5 +/- 10.6, years) never-treated patients with HT and age-matched control group of 40 (47 +/- 8.6, years) normotensive individuals. H-FABP levels were determined in all subjects. We evaluated arterial stiffness and wave reflections of study population, using applanation tonometry (Sphygmocor). Carotid-femoral pulse wave velocity (PWV) was measured as indices of elastic-type, aortic stiffness. The heart rate-corrected augmentation index (AIx@75) was estimated as a marker of wave reflections.ResultsCarotid-femoral PWV (10.5 +/- 2.2 vs. 8.7 +/- 1.6, m/s, P = 0.0001) and AIx@75 (22.7 +/- 9.5 vs. 15 +/- 11, %, P = 0.001) were significantly higher in patients with HT than control group. H-FABP levels were increased in hypertensive patients compared with control group (21.1 +/- 14.8 vs. 12.9 +/- 8.5, ng/ml, P = 0.002). In multiple linear regression analysis, we found that the body mass index (beta = 0.42, P = 0.0001) and carotid-femoral PWV (beta = 0.23, P = 0.03) were significant determinants of H-FABP levels.ConclusionArterial stiffness is associated with serum H-FABP levels, a sensitive marker of myocardial damage, in patients with newly diagnosed HT.American Journal of Hypertension (2008). doi 10.1038/ajh.2008.235American Journal of Hypertension (2008); 21, 9, 989-993. doi 10.1038/ajh.2008.235.     

Hyperglycemia-related pathophysiologic mechanisms and potential beneficial actions of melatonin

Chronically-elevated blood glucose initiates a harmful series of processes in which toxic reactive species play crucial roles. Oxidative as well as nitro-oxidative stress is harmful for virtually all biomolecules including lipids, proteins and DNA. Such pathophysiologic mechanisms eventually results in cellular dysfunction, apoptosis or necrosis. Melatonin is a multifunctional indolamine which counteracts several pathophysiologic steps and displays significant beneficial effects against hyperglycemia-induced cellular toxicity. These are related to melatonin's antioxidative, anti-inflammatory and possibly epigenetic regulatory properties. Current knowledge encourages using this non-toxic indolamine either as a sole treatment or in conjunction with other treatments for inhibition of the biohazards of hyperglycemia.     

Calcium loss from root canal dentin following EDTA, EGTA, EDTAC, and tetracycline-HCl treatment with or without subsequent NaOCl irrigation

The aim of this study was to determine the extent of calcium removal on root canal dentin after 17% EDTA, 17% EGTA, 15% EDTAC, and 1% tetracycline-HCl treatment; with or without subsequent use of 2.5% NaOCl. Extracted single-rooted human teeth were bisected longitudinally and the root halves (n=100) were isolated with nail varnish, leaving the root canal exposed. The samples were immersed in the test solutions for 1 and 5 minutes, after which the amount of calcium ion (Ca(2+)) release into the solutions was determined by flame photometry. Regardless of treatment time, all single (treatment solution only) and combined (treatment solution with subsequent NaOCl application) irrigation regimens removed significantly more Ca(2+) than control treatment (distilled water). Compared with other groups, treatment with 17% EDTA and 17% EDTA + 2.5% NaOCl resulted in the maximum amount of Ca(2+) removal from root canal dentin (p<0.05). All combined-treatment groups except 17% EGTA + 2.5% NaOCl removed significantly more Ca(2+) than their single-treatment versions (p<0.05). Within each test group, extending the treatment time to 5 minutes resulted in significantly more Ca(2+) removal (p<0.05).     

Effect of transcatheter aortic valve implantation on QT dispersion in patients with aortic stenosis

Background QT dispersion （QTd） is a predictor of ventricular arrhythmia. Ventricular arrhythmia is an important factor influencing morbidity and mortality in patients with aortic stenosis. Surgical aortic valve replacement reduced the QTd in this patients group. However, the effect of transcatheter aortic valve implantation （TAVI） on QTd in patients with aortic stenosis is unknown. The aim of this study was to investigate the effect of TAVI on QTd in patients with aortic stenosis. Methods Patients with severe aortic stenosis, who were not candi-dates for surgical aortic valve replacement due to contraindications or high surgical risk, were included in the study. All patients underwent electrocardiographic and echocardiographic evaluation before, and at the 6th month after TAVI, computed QTd and left ventricular mass index （LVMI）. Results A total 30 patients were admitted to the study （mean age 83.2 ± 1.0 years, female 21 and male 9, mean valve area 0.7 ± 3 mm2）. Edwards SAPIEN heart valves, 23 mm （21 patients） and 26 mm （9 patients）, by the transfemoral approach were used in the TAVI procedures. All TAVI procedures were successful. Both QTd and LVMI at the 6th month after TAVI were significantly reduced com-pared with baseline values of QTd and LVMI before TAVI （73.8 ± 4 ms vs. 68 ± 2 ms, P=0.001 and 198 ± 51 g/m2 vs. 184 ± 40 g/m2, P=0.04, respectively）. There was a significant correlation between QTd and LVMI （r=0.646, P〈0.001）. Conclusions QTd, which malign ventricular arrhythmia marker, and LVMI were significantly reduced after TAVI procedure. TAVI may decrease the possibility of ventricu-lar arrhythmia in patients with aortic stenosis.     

Efficacy of melatonin, mercaptoethylguanidine and 1400W in doxorubicin- and trastuzumab-induced cardiotoxicity

Doxorubicin (DOX) and Trastuzumab (TRAST) are effective agents for the treatment of many neoplastic diseases. Cardiotoxicity is a major side effect of these drugs and limit their use. In this study, the possible protective effects of melatonin (MEL), mercaptoethylguanidine (MEG), or N-(3-(aminomethyl) benzyl) acetamidine (1400W) against the cardiotoxicity of DOX and TRAST were tested. Male Sprague-Dawley rats received an injection of DOX (20 mg/kg) alone or in combination with TRAST (10 mg/kg) to induce cardiotoxicity; daily treatments with MEL (10 mg/kg × 2), MEG (10 mg/kg × 2), or 1400W (10 mg/kg × 2) were begun 36 hr before and continued for 72 hr after DOX and TRAST administration. Oxidant/antioxidant indices of the cardiac tissue, namely, malondialdehyde, superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), as well as serum levels of creatine phosphokinase (CK-MB) were measured. Additionally, the injury scores were evaluated histopathologically. Malondialdehyde levels were significantly higher, while SOD and GSH-Px activities were significantly reduced in rats with DOX- or DOX+TRAST-induced cardiotoxicity compared to normal values. All three treatment agents significantly reversed oxidative stress markers. Serum CK-MB levels were significantly increased after treatment with DOX and DOX+TRAST; these changes were also reversed by each of the treatments and resulted in near normal levels. Both the DOX- and DOX+TRAST-treated rats presented similar histopathologic injuries; in the animals treated with the protective agents, histologic protection of the cardiac tissue was apparent. These results suggested that MEL, MEG, as well as 1400 W are effective in preventing DOX- or DOX+TRAST-induced cardiotoxicity.     

Acute and chronic effects of electroconvulsive treatment on oxidative parameters in schizophrenia patients

Electroconvulsive therapy (ECT) is an effective treatment alternative for schizophrenia. Previous studies have already indicated the possible effects of oxidative stress in this disorder. However, there have been no previous studies evaluating the effects of ECT on the oxidative stress in these patients. We therefore aimed to investigate the acute and chronic effects of ECT on serum levels of oxidant and antioxidant molecules in schizophrenia patients (n = 28). The serum MDA and CAT levels of the patients with schizophrenia were higher than that of the controls before ECT (n = 20) but there was no significant difference in the serum NO and GSH levels of the patient groups compared to the controls. We found that the NO levels of the patients were higher than the controls in the group experiencing their first episode but not in the chronic group. There was a significant clinical improvement in the patients in terms of BPRS, SANS and SAPS reduction after the 9th ECT, but not the 1st ECT. Serum MDA levels were significantly reduced compared to the baseline after the 9th ECT session although there was no significant difference after the 1st session. Separate evaluation of the patient groups revealed that the significant MDA decrease following ECT was in the patients experiencing their first episode and not in the chronic group. No significant difference was noted in the serum levels of other oxidant and antioxidant molecules after either the 1st or 9th ECT session. These results suggest that ECT does not produce any negative effect on oxidative stress in patients with schizophrenia.     

Pituitary volume in patients with panic disorder

Panic patients have many functional deficiencies in the hypothalamic-pituitary-adrenal (HPA) axis. Previous studies have shown changed pituitary gland volume in some psychiatric disorders that have functional deficiencies in the HPA axis. However, to date no study has evaluated the pituitary gland volume in patients with panic disorder (PD). We investigated the pituitary gland volume in patients with PD (n = 27) and age- and sex-matched healthy controls (n = 27), using 1.5-T magnetic resonance imaging in this study. Analysis showed that patients with PD had significantly smaller pituitary volume compared to healthy subjects. Patients with agoraphobia especially had a significantly smaller pituitary volume than patients without agoraphobia. There was a significant relationship between the pituitary volume and both the severity of symptoms and the illness duration in the patient group. The results show that patients with PD have reduced pituitary volume, which may reflect the functional abnormalities seen in this disorder. These findings may help us better understand the pathology of PD.