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21.
OBJECTIVE: To investigate the effects of growth hormone (GH) deficiency on serum lipid and leptin concentrations in hypopituitary patients taking conventional replacement therapy and to determine the relations between leptin and gender and anthropometric and metabolic variables. SUBJECTS: Twenty-one GH deficient adult hypopituitary patients (15 women, six men) and 21 (14 women, seven men) age, sex and body mass index (BMI) matched healthy controls. MEASUREMENTS: After an overnight fast, anthropometric parameters were measured and body composition was determined by a bioelectrical impedance analyser. Venous blood samples were obtained for the measurements of glucose, total cholesterol, high density lipoprotein (HDL) cholesterol, triglyceride, intact insulin, insulin-like growth factor 1 (IGF-1) and leptin concentrations. Serum leptin and hormones were analysed by radioimmunoassay. RESULTS: Hypopituitary patients with GH deficiency showed significantly higher triglyceride, total and low density lipoprotein (LDL) cholesterol and lower HDL cholesterol concentrations on conventional replacement therapy. The unfavourable lipid profile was particularly evident in women. Significantly higher leptin concentrations were found in patients compared with healthy controls with similar body fat content (23. 5+/-11.8 ng/ml vs 11.7+/-6.9 ng/ml, P=0.01). This difference remained significant even when leptin values were expressed in relation to fat mass percentage (0.79+/-0.40 vs. 0.42+/-0.17 ng/ml%, P<0.05) and fat mass kg (1.32+/-0.81 vs 0.66+/-0.30 ng/ml kg, P<0. 05). Significant positive correlations were observed between leptin concentrations and body fat percentage and age in the control group. In patients the sole significant relation between leptin and study parameters was the positive correlation observed between leptin and total cholesterol concentrations. Serum leptin concentrations were significantly higher in women than men in the control group, but not in the patients. No significant gender difference was observed when leptin concentrations were expressed in relation to fat mass (percentage and kg). CONCLUSION: Growth hormone deficient hypopituitary patients (particularly women) on conventional replacement therapy have a more atherogenic lipid profile. Leptin concentrations are increased in GH deficient adults even after adjustment for percentage body fat and body fat mass (kg). Although the nature of our data does not allow us to draw any conclusions on the mechanism(s) of increased leptin concentrations in GH deficiency, decreased central sensitivity to leptin and increased leptin production from per unit fat mass, or alterations in leptin clearance, might be operative.  相似文献   
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At present, an intensive effort for prevention of neuroma formation following peripheral nerve section continues. It has been recently suggested that surgical pinealectomy (Px) induces elevation of the collagen content in the granulation tissue of a wound, while melatonin application after Px suppresses elevation of the collagen accumulation in the tissue. The aim of the present study was to assess whether melatonin had the ability to suppress collagen production and neuroma formation following peripheral nerve transection. A total of 40 male rats (four groups of 10) were left intact (intact controls) or sham operated (sham group), were Px, or were Px and given melatonin (Px + melatonin group). All animals underwent a surgical intervention consisting of right sciatic nerve neurectomy. After 4 wk, the animals were killed following intracardiac perfusion. Gross morphology of neuroma formation in the proximal nerve segment was examined and proximal neuroma evaluated. Macroscopic and microscopic findings revealed that Px caused a proliferation of connective tissue and large neuroma formation at the proximal ends of transected nerves. Stereological analysis showed that there was a statistically significant reduction in connective tissue content of the same region in Px animals treated with melatonin (P < 0.005). The results achieved in a rodent model of sciatic nerve neuroma formation showed that there was a positive correlation between macroscopic and microscopic observations, and that melatonin enhanced axonal regeneration presumably due to its inhibitory effect on neuroma formation.  相似文献   
23.
BACKGROUND: Postoperative brachial plexus injury is often reported because the brachial plexus is stretched by sternotomy and the use of sternal retractors during open heart surgery. In many studies, brachial plexus injuries have been demonstrated by postoperative electrophysiological studies in susceptible patients. In this study, we estimated the incidence, severity, and type of brachial plexus injuries by routine preoperative and postoperative electrophysiological studies of patients undergoing open heart surgery. METHODS: Patients undergoing coronary artery bypass grafting (CABG) surgery (Group 1), heart valve surgery (Group 2), or peripheral vascular surgery (Group 3) were included in the investigation. Electrophysiological studies of both upper extremities were performed five days before and three weeks after the operation. RESULTS: Peripheral nerve problems were found preoperatively in 23 of the 112 patients (21 %). These problems persisted, but similar findings were obtained postoperatively from the left upper extremities of six of the 42 CABG (14 %) and two of the 24 heart valve (8 %) patients who had had normal preoperative evaluations. The patients with injured nerves were older and had undergone longer operation times. There were no differences between the patients with injured nerves and the others with respect to mammary artery harvesting or other operative variables. CONCLUSIONS: There are no reports in the literature of routine preoperative and postoperative electrophysiological studies in large patient groups to evaluate brachial plexus injury during open heart surgery. It is known that heart surgery sometimes causes partial brachial plexus injury, especially in the lower trunk. However, these peripheral nerve problems are usually not considered clinically important and are not investigated. Patients undergoing open heart surgery must be closely followed up for peripheral nerve injury during the postoperative period.  相似文献   
24.
Several studies indicate that thrombosis plays an important role in the pathogenesis of coronary heart disease (CHD). Fibronectin is a multifunctional protein in plasma, other body fluids, and cell surface and plays an important role in platelet functions, including mediation of cell-cell and cell-surface interactions. Sialic acid is a regular constituent of glycoproteins and gangliozides in the outer cell membrane of mammalian cells. Therefore, the sialic acid content of platelets, which are characterized by their ability to aggregate with each other, can be important in leading to thrombus formation. In this study, platelet fibronectin, sialic acid-, and adenosine diphosphate (ADP)-induced platelet aggregation levels were determined in patients with CHD. Platelet sialic acid concentrations were determined by Warren's method. Platelet aggregation tests with ADP in platelet-rich plasma (PRP) were analyzed by use of an aggregometer. Platelet homogenate fibronectin levels were determined by ELISA. Total protein levels were determined by Lowry method. Our results indicate that, in patients with no vessel disease (patients with no obstructed vessel but suffering from chest pain, like angina pectoris) platelet fibronectin levels were significantly lower than the total of the other patients (patients with 1, 2, or 3 obstructed coronary vessels) (p<0.05). Sialic acid levels in patients with no vessel disease were significantly lower than the total of the patient group (p<0.05). There was significant (+) correlation between platelet aggregation, platelet fibronectin, platelet sialic acid, and severity of disease (p<0.05). Our preliminary findings suggest that, especially platelet fibronectin levels potentially represent a pathogenic factor for CHD.  相似文献   
25.

Background

The aim of this study was to evaluate the sensitivity and specificity of physical examination findings and functional tests in adult acute wrist trauma patients who presented to the emergency department (ED) and to create a reliable and practical clinical decision rule for determining the necessity of radiography in wrist trauma.

Methods

This prospective observational study was conducted in a tertiary ED. Each patient was checked for 18 physical examination findings and functional tests. Patients with suspected fracture were enrolled consecutively. Antero-posterior and lateral wrist views were performed for each patient. All radiographical studies were interpreted by an orthopedic surgeon. The prevalence, sensitivity and specificity, negative and positive predictive values of each finding were calculated. A modeling for predicting fractures was created using computer.

Results

207 patients were evaluated and 69 patients (33.3%) had fractures. The most common encounterd fracture site was distal radius (29.5%). The most sensitive examination finding was pain in dorsiflexion (95.7%) and the most specific finding was ecchymosis (97.8%). Wrist edema, deformity and pain aggravated by pronation were found to be strong predictors of fracture. The area under the receiver operating characteristic curve at internal validation for a prediction model based on these three predictors was 0.88 (95% CI: 0.83-0,93). The overall sensitivity and specificity of this model were 94% (95% CI: 85-98%) and 51% (95% CI 43-60%) respectively. According to the model created in this study, 34% of acute blunt wrist trauma patients do not require any X-ray imaging.

Conclusions

This triple modeling may be used as an effective decision rule for predicting all wrist fractures in the ED and in the disaster setting.  相似文献   
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Platelets have the capacity to release mediators with potent inflammatory or anaphylactic properties. Platelet factor-4 (PF4) and beta-thromboglobulin (BTG) are two of these mediators. On the other hand, plasminogen activator inhibitor-1 (PAI-1) and tissue plasminogen activator (tPA) are two important mediators of fibrinolysis. Both mediators are secreted mainly by vascular endothelium. Plasma levels of PF4, BTG, PAI-1, and tPA may show changes in chronic inflammatory diseases such as asthma. This study examined the role of thrombocytes and the function of the endothelium in asthmatic patients during an attack and during a stable phase. Eighteen patients with known allergic asthma who came to our emergency department with an asthma attack and 14 control subjects were included in the study. Blood samples were taken after starting therapy with salbutamol inhalation. Lung function tests were performed after receiving the first emergency therapy for asthma. Plasma levels of PF4, BTG, PAI-1, tPA were determined before starting steroid therapy and after receiving 1 week of steroid therapy. Plasma levels of PF4 among patients with an asthma attack were significantly higher than those of controls (150.5+/-8.92 IU/mL vs. 92.5+/-7.63 IU/mL, p<0.001). A further increase in plasma PF4 levels was detected after steroid therapy (163.5+/-9.16 IU/mL). Plasma BTG levels of patients on admission were not statistically different from those in the control group (140.4+/-6.34 IU/mL vs. 152.2+/-8.71 IU/mL). An increase was detected after therapy (171.6+/-7.27 IU/mL) and post-treatment plasma levels were statistically meaningful versus the controls. Plasma levels of tPA and PAI were statistically higher than those in controls in asthmatic patients on admission (6.01+/-2.72 vs. 5.4+/-2.3 ng/mL for tPA and 75.2+/-27.2 ng/mL vs. 32.7+/-14.3 ng/mL for PAI-1). Further increases were detected in two parameters after 1 week of therapy with steroids (tPA levels were 6.85+/-2.96 ng/mL and PAI-1 levels were 83.5+/-29.6 ng/mL). There seems to be an increased activity of platelets during an asthma attack. Elevated PAI-1 and tPA levels may also indicate the activated endothelium in asthma. Increases of plasma levels of PAI-1 and tPA after steroid therapy need further investigation because elevated PAI-1 levels enhance airway remodeling.  相似文献   
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