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MM El-Omar BSc MRCP K Ray MRCP R Geary MB ChB 《International journal of clinical practice》1996,50(2):115-116
SUMMARY We present the case of a young female who suffered a massive intracerebral bleed following the ingestion of a small quantity of amphetamine (speed). Physicians should be aware that amphetamine abuse can lead to cerebrovascular events in young adults. 相似文献
123.
Renin-angiotensin II response to the hemodynamic pathology of ovines with ventricular septal defect 总被引:1,自引:0,他引:1
We studied the response of the renin-angiotensin system (RAS) to a surgically created ventricular septal defect (VSD) in immature ovines and also the role of angiotensin II in the pathophysiology of VSD in the chronically instrumented ovine. Plasma renin activity (PRA) was increased from 2.39 +/- 1.1 to 3.78 +/- 1.4 ng/ml/hr (p less than 0.05, n = 17) after VSD but not after sham procedure. The change in PRA was positively correlated with the amount of left-to-right shunt through the VSD (r = 0.74, p less than 0.05). Inhibition of angiotensin II effect with saralasin (10 micrograms/kg/min) or angiotensin II production with captopril (2 mg/kg) lowered systemic resistance (Rs) by 14% and 34%, respectively (p less than 0.05), and raised pulmonary resistance (Rp) by 35% and 77%, respectively (p less than 0.05). Thirty minutes following captopril, the ratio of pulmonary to systemic flow (Qp/Qs) decreased from 3.31 +/- 0.18 to 2.15 +/- 0.18 (p less than 0.05) while total pulmonary flow fell from 7.15 +/- 0.38 to 5.92 +/- 0.34 l/min/M2 (p less than 0.05, n = 11). Systemic flow increased from 2.17 +/- 0.14 to 2.86 +/- 0.33 l/min/M2 (p less than 0.05) despite a reduction in left atrial pressure (17.3 +/- 1.0 vs. 13.0 +/- 1.7, p less than 0.01). Reinfusion of angiotensin II (0.02 micrograms/kg/min) into the central aorta after captopril returned the hemodynamics to baseline including a rise in Rs and fall in Rp. Exogenous angiotensin II alone (0.08 micrograms/kg/min) or a threefold stimulation in PRA with furosemide (2 mg/kg) caused little hemodynamic effect.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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V Ambade MM Arora P Singh B L Somani D Basannar 《Medical Journal Armed Forces India》2009,65(3):216-220
Background
Abnormalities of catecholaminergic function have been hypothesised in causation of depressive illness. Electroconvulsive therapy (ECT) is postulated to have noradrenergic mechanism of action. We studied the clinical utility of estimating catecholamines level changes after ECT.Methods
Plasma adrenaline, noradrenaline and dopamine in healthy controls and depressed patients were estimated by high performance liquid chromatography with electrochemical detection method before and after ECT.Result
Mean ± standard deviation of plasma adrenaline, noradrenaline and dopamine in controls was 36.7 ± 13.2, 209.3 ± 76, 21.8 ± 9.5 ng/L respectively, while in depressed patients before and after ECT it was found to be 32.5 ± 12.0, 419.3 ± 167.7, 22.1 ± 16.0ng/ L and 37.2 ± 19.6, 386.1 ± 168.4, 22.3 ± 15.5ng/L respectively. Correlation of adrenaline, noradrenaline and dopamine concentration with scores of Beck Depression Inventory, Suicidal Ideation Scale and Melancholia Inventory was positive but statistically not significant and poor. Based on the cut off values of noradrenaline, only 62% cases could be categorized as abnormal, which after ECT reduced to 50%, whereas post ECT psychiatric ratings was normal in about 78% cases.Conclusion
There is no clinical significance of estimating adrenaline, noradrenaline and dopamine in depressed patients.Key Words: Electroconvulsive therapy, Adrenaline, Noradrenaline, Dopamine, Psychiatric scales 相似文献129.
SM Vieira HP Lemos R Grespan MH Napimoga D Dal-Secco A Freitas TM Cunha WA Verri Jr DA Souza-Junior MC Jamur KS Fernandes C Oliver JS Silva MM Teixeira FQ Cunha 《British journal of pharmacology》2009,158(3):779-789
Background and purpose:
Chemokines orchestrate neutrophil recruitment to inflammatory foci. In the present study, we evaluated the participation of three chemokines, KC/CXCL1, MIP-2/CXCL2 and LIX/CXCL5, which are ligands for chemokine receptor 2 (CXCR2), in mediating neutrophil recruitment in immune inflammation induced by antigen in immunized mice.Experimental approach:
Neutrophil recruitment was assessed in immunized mice challenged with methylated bovine serum albumin, KC/CXCL1, LIX/CXCL5 or tumour necrosis factor (TNF)-α. Cytokine and chemokine levels were determined in peritoneal exudates and in supernatants of macrophages and mast cells by elisa. CXCR2 and intercellular adhesion molecule 1 (ICAM-1) expression was determined using immunohistochemistry and confocal microscopy.Key results:
Antigen challenge induced dose- and time-dependent neutrophil recruitment and production of KC/CXCL1, LIX/CXCL5 and TNF-α, but not MIP-2/CXCL2, in peritoneal exudates. Neutrophil recruitment was inhibited by treatment with reparixin (CXCR1/2 antagonist), anti-KC/CXCL1, anti-LIX/CXCL5 or anti-TNF-α antibodies and in tumour necrosis factor receptor 1-deficient mice. Intraperitoneal injection of KC/CXCL1 and LIX/CXCL5 induced dose- and time-dependent neutrophil recruitment and TNF-α production, which were inhibited by reparixin or anti-TNF-α treatment. Macrophages and mast cells expressed CXCR2 receptors. Increased macrophage numbers enhanced, while cromolyn sodium (mast cell stabilizer) diminished, LIX/CXCL5-induced neutrophil recruitment. Macrophages and mast cells from immunized mice produced TNF-α upon LIX/CXCL5 stimulation. Methylated bovine serum albumin induced expression of ICAM-1 on mesenteric vascular endothelium, which was inhibited by anti-TNF-α or anti-LIX/CXCL5.Conclusion and implications:
Following antigen challenge, CXCR2 ligands are produced and act on macrophages and mast cells triggering the production of TNF-α, which synergistically contribute to neutrophil recruitment through induction of the expression of ICAM-1. 相似文献130.
Lacina L Dvoránkova B Smetana K Chovanec M Plzák J Tachezy R Kideryová L Kucerová L Cada Z Boucek J Kodet R André S Gabius HJ 《International journal of radiation biology》2007,83(11-12):837-848
PURPOSE: The microenvironment established by stromal cells may or may not influence phenotypic aspects of epithelial cells and may be relevant for tumor and stem cell biology. We address this issue for keratinocytes using tumor-derived stromal cells in a co-culture system. MATERIALS AND METHODS: We isolated stromal cells from human squamous cell carcinoma tissue and studied their effect on phenotypic characteristics of normal human interfollicular keratinocytes in vitro. RESULTS: Stromal fibroblasts significantly influence immuno- and lectin cytochemical properties of co-cultured normal keratinocytes. Expression of keratins 8 and 19, the nucleolar protein nucleostemin, parameters related to adhesion/growth-regulatory galectins and the epithelial-mesenchymal transition were altered. This biological activity of tumor-derived stromal cells, which did not require cell contact, appeared to be stable, because it was maintained during passaging of keratinocytes in the absence of cancer cells. CONCLUSIONS: Tumor-derived stromal fibroblasts acquire distinct properties to shape a microenvironment conducive to altering the phenotypic characteristics of normal epithelial cells in vitro. 相似文献