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Objective:To determine the total oxidant status (TOS), total antioxidant status (TAS), and the 8-hydroxy-2′-deoxyguanosine (8-OHdG) levels and their interrelationship in the saliva of children undergoing fixed orthodontic therapy.Materials and Methods:Thirty children were randomly divided into three groups. The attachments were bonded to all of the teeth using three different orthodontic composites: Transbond XT, Kurasper F, and GrenGloo. The salivary levels of TOS, TAS, and 8-OHdG were determined three times, as follows: before treatment (T1) and at 1 month (T2) and 3 months (T3) following appliance placement. All data were statistically analyzed.Results:There were no significant differences in TOS, TAS, and 8-OHdG within the same time periods among the three different orthodontic composites (P > .05). TAS in all composite groups decreased over time. These decreases were found to be significant for Kurasper F and GrenGloo at the T1–T3 and T2–T3 time periods (P < .05). In all composite groups 8-OHdG decreased between T1 and T2 (P < .05). However, 8-OHdG in all composite groups increased from T2 to T3. These differences in 8-OHdG were significant in Kurasper F and GrenGloo (P < .05).Conclusions:Fixed orthodontic appliances bonded with the tested composites did not increase the cytotoxicity markers in saliva.  相似文献   
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Pituitary - Although it is well known that acromegaly causes enlargement in the extremities, studies investigating the effects of acromegaly on tendons, muscles and soft tissue are limited. The...  相似文献   
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Arterial hypertension is one of the physical complications of chronic lead exposure. Hypertension has effects on aortic elastic properties. The aim of this study was to evaluate the aortic elastic properties in workers occupationally exposed to lead. Forty‐one workers who were exposed to lead and 39 healthy controls were included in the study. All patients underwent transthoracic echocardiography for detecting aortic elastic parameters. There were no differences in baseline characteristics between the lead‐exposure group and controls. Aortic strain (9.4%±4.5% vs 12.4%±4.2%, P=.004) and aortic distensibility (0.45±0.21 cm2/dyn vs 0.55±0.20 cm2/dyn, P=.046) were decreased in patients with lead exposure compared with controls. There was a negative significant weak correlation between aortic strain and (r=−0.294, P=.008) lead levels. There was no significant correlation between aortic distensibility and any other echocardiographic parameters. This study suggests that chronic exposure to lead is related to impairment of aortic elasticity parameters.

Lead contamination (such as that emitted from house paint, gasoline, batteries, and other sources) may cause a wide variety of body organ complications.1 Despite the still manifested divergences of opinion, it seems that chronic exposure to lead represents a risk for arterial hypertension development. Functional changes within the arterial wall both in smooth muscles and the endothelium might result in arterial hypertension caused by chronic exposure to lead compounds.2 Blood pressure (BP) was found to be increased in workers with blood lead concentrations of 7 μg/L on average.3 According to the World Health Organization (2000), the level of 400 μg/L is accepted as safe to avoid possible adverse health effects, but American Conference Governmental and Industrial Hygienists suggest an even lower value of <300 μg/L.Hypertension has effects on the aorta (decreased aortic distensibility and increased aortic stiffness). Aortic strain is a simple and useful parameter of transthoracic echocardiography. Some studies have suggested that aortic elastic parameters can be used as an independent predictor of all‐cause and cardiovascular mortality in hypertensive patients.4, 5 In previous studies, the relationship between lead exposure and arterial hypertension has been demonstrated, and findings suggest that arterial hypertension and organ complications of arterial hypertension are more frequent in workers with lead exposure. Until now, there have been no data on the effects of lead exposure on aortic stiffness. The aim of this study was to evaluate the effects of lead on aortic elasticity parameters.  相似文献   
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Bilateral variations of renal vessels were encountered during the dissection of a 54-year-old male cadaver. There were triple renal arteries bilaterally, double renal veins on the right, and an unusual formation of renal vein on the left side. A bilateral occurrence of triple renal arteries has not been encountered in the literature, so does an incidence. Additional renal vessels have the potential to cause clinical complications such as hydronephrosis. Their existence has utmost importance in surgical and radiological interventions and radiological examinations.  相似文献   
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Atrial fibrillation (AF), which is the most common cardiac arrhythmia, may cause serious symptoms and impair quality of life.1 The development of AF is associated with many risk factors, including age, male gender, hypertension, heart failure, valvular disease, diabetes mellitus (DM) and left atrial (LA) enlargement.2-4 Electrical and/or mechanical remodelling of the atria is thought to be a pathophysiological characteristic of AF.5The pregnant state may be pro-dysrhythmic. This is related to the cardiovascular, hormonal, haemodynamic and autonomic changes during healthy pregnancy. Levels of oestrogen and β-human chorionic gonadotropin increase dramatically. Haemodynamic changes include an increase in circulating blood volume, which increases cardiac output. This results in myocardial stretch and an increase in cardiac end-diastolic volume. High plasma catecholamine concentrations and adrenergic receptor sensitivity increase sympathetic tone. All these changes in pregnant women may make them more prone to dysrhythmogenesis.6Most pregnant women complain of palpitations, dizziness and even syncope, but these symptoms are rarely associated with cardiac dysrhythmias. AF is the most common clinically significant cardiac arrhythmia in the general population but it is rarely seen in pregnant women. When it occurs, it can represent a benign, self-limited lone episode of AF or may be secondary to congenital or rheumatic valvular disease, hypertrophic cardiomyopathy, thyroid disease, or pre-excitation syndrome.Two simple electrocardiogram (ECG) markers, namely maximum P-wave duration (Pmax) and P-wave dispersion (PD), have been used to evaluate intra- and inter-atrial conduction times and the inhomogeneous propagation of sinus impulses, which are well-known electrophysiological characteristics of the atrium prone to fibrillation.7,8 Prolonged Pmax and PD have been reported to represent an increased risk for AF in patients with no underlying heart disease.7,8 Besides, evidence from laboratory and epidemiological research suggests that systemic inflammation may play a role in AF aetiology.9 It has also been demonstrated that atrial electromechanical coupling, measured by tissue Doppler imaging (TDI), as significantly longer in patients with paroxysmal AF than in control groups.10,11To our knowledge, no study evaluating PD and atrial electromechanical coupling has been investigated in pregnant subjects without additional systemic disease. Therefore, in this study we aimed to examine atrial electromechanical coupling and PD, reflecting inter-atrial conduction times in pregnant subjects.  相似文献   
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BackgroundWe aim to investigate the effects of dipeptidyl-peptidase-4 inhibitor (Vildagliptin-VG) on DDR-1 as a marker for endocrine progenitor cells, β-cell regeneration, and apoptosis in neonatal streptozotocin (n2-STZ) diabetics.MethodsNeonatal rats were divided into two main groups as short- and long-term treatment, each consisted of four groups; (1) Control, (2) n2-STZ diabetic (single dose of 100 mg/kg STZ at 2nd day of birth), (3) n2-STZ + VG (60 mg/kg/day VG orally; for 8 and 28 days), (4) VG (60 mg/kg/day orally; for 8 and 28 days). Blood glucose levels and body weights were measured, and the tissue sections were immunostained using insulin, glucagon, somatostatin, PCNA, Pdx-1 and DDR-1 antibodies. The TUNEL method was used for apoptosis.ResultsThe number of β cells in islets of the n2-STZ + VG group increased compared to the n2-STZ group; insulin (+) cells were observed individually or as small clusters in exocrine tissue, between pancreatic duct epithelial cells, and around the ducts. The number of Pdx-1 and DDR-1 positive cells in islet and extra-islet pancreas tissue was elevated as a result of VG application compared to the STZ diabetic group; the number of double positive cells for DDR-1 and insulin increased in n2-STZ + VG rats.ConclusionWe showed that vildagliptin promotes β cell neogenesis and regeneration, stimulates DDR-1 expression as an endocrine cell progenitor marker, suppresses apoptosis, induces islet cell proliferation and rearranges islet morphology in the n2-STZ diabetes model.  相似文献   
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