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BACKGROUND: Thrombotic thrombocytopenic purpura (TTP) is a multisystem disorder characterised by platelet aggregation causing microvascular occlusion. Early diagnosis and utilization of plasmapheresis can provide an improvement in prognosis. CASE REPORT: A 17 year old male with classical findings of TTP was later diagnosed as systemic lupus erythematosus (SLE). Plasmapheresis resulted in the significant amelioration of the course. CONCLUSION: The coexistence of TTP and SLE may facilitate a better understanding of in the pathophysiology of TTP. These association may provide the role of autoimmunity in TTP. SLE should be considered in the differential diagnosis of patients with TTP because of therapeutic implications.  相似文献   
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OBJECTIVE: An evaluation of growth hormone (GH) testing for GH deficiency (GHD) in childhood is confounded by the lack of a world-wide consensus on the definition of GHD. Although a single GH test remains the most powerful biochemical tool in the evaluation of a child with growth failure, the test remains far from ideal. Withdrawal of somatostatin (SS) infusion is followed by a rebound rise of GH thought to be mediated by endogenous GH-releasing hormone (GHRH) function. This study was designed to compare the GH response to 90 min SS infusion in children with normal GH secretion versus children with GH deficiency. METHODS: Ten children with GHD and 10 healthy controls (NC) have been evaluated for GH response to somatostatin infusion withdrawal (SSIW) and compared with response of two provocative tests, glucagon plus propranolol test and L-Dopa test. All children received constant infusion of somatostatin for 90 min (3 microg/kg per h, Stilamin, Serono, Aubonne, Switzerland). In order to determine GH, blood samples were obtained 90 min before the SS infusion and 0, 15, 30, 45, 60, 75, and 90 min after the cessation of infusion. RESULTS: Growth hormone peak levels with SSIW were significantly lower in GH deficient children than in healthy children (2.5 +/- 1.2 ng/dL, vs 21.9 +/- 5.3 ng/dL, respectively, P < 0.01). No adverse effects were observed during or after somatostatin infusion. CONCLUSION: In the present study, SSIW elicited a significant GH rise in healthy children but not in children with GH deficiency. Although further controlled studies using more data are necessary to expand these findings, the results suggested that children with GH deficiency can be reliably discriminated from healthy children by SSIW.  相似文献   
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Image quality in non‐contrast‐enhanced (NCE) angiograms is often limited by scan time constraints. An effective solution is to undersample angiographic acquisitions and to recover vessel images with penalized reconstructions. However, conventional methods leverage penalty terms with uniform spatial weighting, which typically yield insufficient suppression of aliasing interference and suboptimal blood/background contrast. Here we propose a two‐stage strategy where a tractographic segmentation is employed to auto‐extract vasculature maps from undersampled data. These maps are then used to incur spatially adaptive sparsity penalties on vascular and background regions. In vivo steady‐state free precession angiograms were acquired in the hand, lower leg and foot. Compared with regular non‐adaptive compressed sensing (CS) reconstructions (CSlow), the proposed strategy improves blood/background contrast by 71.3 ± 28.9% in the hand (mean ± s.d. across acceleration factors 1–8), 30.6 ± 11.3% in the lower leg and 28.1 ± 7.0% in the foot (signed‐rank test, P < 0.05 at each acceleration). The proposed targeted reconstruction can relax trade‐offs between image contrast, resolution and scan efficiency without compromising vessel depiction. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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Systemic sclerosis (SSc) is a disease characterized by skin and internal organ involvement. There is progressive accumulation of extracellular matrix components in the skin and involved organs. Tissue fibrosis is the prominent reason for mortality, and still, there is no satisfactory treatment. The aim of this study was to evaluate the effects of urotensin-II (U-II) antagonist palosuran in an animal model of scleroderma. We also planned to measure U-II, endothelin-1 (ET-1), and transforming growth factor-β1 (TGF-β1) levels, as well as the association of these levels with dermal thickness. Twenty-four male mice were included in this study and they were divided into three groups—group 1: control group, group 2: fibrosis group, and group 3: fibrosis + palosuran treatment group. Fibrosis + palosuran treatment in group 3 reduced ET-1, U-II, and TGF-β1 levels. In total, the diminished values were statistically significant in the ET-1 and TGF-β1 levels (p?<?0.05). Dermal thickness was higher in the fibrosis group, when compared with the other groups. There was no significant relationship between dermal thickness and ET-1, U-II, or TGF-β1 levels (p?>?0.05). It is believed that U-II is an important mediator in SSc, and its antagonism with palosuran could be a new treatment choice in SSc.  相似文献   
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Pulmonary arterial hypertension (PAH) is a progressive and a life-threatening disease with its high morbidity and mortality ratios. On searching for new shining targets in pathogenesis, we noticed, in our previous studies, urotensin-II (UII) in systemic sclerosis with potent angiogenic and pro-fibrotic features. Owing to the mimicking properties of UII with endothelin-1 (ET1), we attempted to investigate the effect of palosuran in a PAH rat model. Thirty rats were randomly divided into three groups, with each group comprising 10 rats: group 1 (control group) received the vehicle subcutaneously, instead of monocrotaline (MCT) and vehicle; group 2 (MCT group) received subcutaneous MCT and vehicle; and group 3 (MCT + palosuran group) received subcutaneous MCT and palosuran. Serum UII, ET1, transforming growth factor-β1 (TGF-β1) levels, pulmonary arteriolar pathology of different diameter vessels, and cardiac indices were evaluated. The ET1, TGF-β1, and UII levels were significantly diminished in the treatment group, similar to the controls (p?<?0.001). Right ventricular hypertrophy index and mean pulmonary arterial pressure scores were also significantly reduced in the treatment group (p?=?0.001). Finally, in the 50–125-μm diameter arterioles, in contrast to Groups 3 and 1, there was a statistically significant thickness (p?<?0.01) in the arteriolar walls of rats in Group 2. The treatment effect on arteries of more than 125-μm diameters was found to be valuable but not significant. Owing to its healing effect on hemodynamic, histological, and biochemical parameters of MCT-induced PAH, palosuran as an antagonist of UII might be an optional treatment alternative for PAH.  相似文献   
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OBJECTIVE:

Pulmonary embolisms occur as a wide spectrum ranging from clinically asymptomatic thrombi to massive thrombi that lead to cardiogenic shock. The purpose of this study was to determine the associations of thrombus localization with risk factors, accompanying disorders, D-dimer levels and the red blood cell distribution width in patients with pulmonary embolism.

MATERIAL AND METHODS:

In 148 patients diagnosed with pulmonary embolism, the presence and anatomical localization of the thrombus were assessed via computed tomographic pulmonary angiography. The accompanying disorders, risk factors, serum D-dimer levels, and red blood cell distribution width of the patients were retrospectively evaluated. ClinicalTrials.gov: NCT02388841.

RESULTS:

The mean age of the patients was 54±16.0 years, and 48 patients were ≥65 years of age. The most frequent accompanying disorders were chronic obstructive pulmonary disease (22%) and malignancy (10.1%), and the most frequent risk factors were recent operation (14.1%) and immobilization (18.2%). Thrombi were most frequently observed in the right pulmonary artery (37.8%). In 31% of the patients, the thrombus was localized to the main pulmonary arteries. Immobile patients exhibited a higher proportion of thrombi in the main pulmonary arteries than mobile patients. The mean D-dimer level and the mean red blood cell distribution width in the patients with thrombi in the main pulmonary arteries were higher than those in the patients with thrombi in more distal pulmonary arterial branches.

CONCLUSION:

Significant associations of proximally localized thrombi with immobilization, the D-dimer levels, and the red blood cell distribution width were observed.  相似文献   
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