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1.
BACKGROUND: Results from several studies indicate that the magnitude of immediate symptoms of type I allergy caused by allergen-induced cross-linking of high-affinity Fc epsilon receptors on effector cells (mast cells and basophils) is not always associated with allergen-specific IgE levels. OBJECTIVE: To investigate the association of results from intradermal skin testing, basophil histamine release and allergen-specific IgE, IgG1-4, IgA and IgM antibody levels in a clinical study performed in birch pollen-allergic patients (n = 18). METHODS: rBet v 1-specific IgEs were measured by quantitative CAP measurements and by using purified Fc epsilon RI-derived alpha-chain to quantify IgE capable of binding to effector cells. Bet v 1-specific IgG subclasses, IgA and IgM levels were measured by ELISA, and basophil histamine release was determined in whole blood samples. Intradermal skin testing was performed with the end-point titration method. RESULTS: Our study demonstrates on the molecular level that the concentrations of allergen-specific IgE antibodies capable of binding to Fc epsilon RI and biological sensitivities are not necessarily associated. A moderate association was found between cutaneous and basophil sensitivity. CONCLUSION: Our results highlight the quantitative discrepancies and limitations of the present diagnostic tools in allergy, even when using a single allergenic molecule. The quantity of allergen-specific serum IgE is only one component of far more complex cellular systems (i.e. basophil-based tests, skin tests) used as indirect diagnostic tests for IgE-mediated allergic sensitivity.  相似文献   
2.
Background The skin microdiallysis technique makes it possible to measure histamine release in intact human skin in vivo directly. In this study we have used the microdialysis technique to characterize histamine release by codeine after intracutaneous injectioin and following skin challenge by a novel atraumatic delivery technique. Objective The purpose of the study was to compare histamine release in human skin by codeine. delivered by an intraprobe drug delivery system (IPD) and intracutaneous injections (ICT), with respect to dose-response relations, kinetics of histamine appearance and decay, corelations between histamine release and skin respones, and reproducibility. Methods Hollow dialysis fibres were inserted intradermally in 12 healthy subjects. Twelve fibres were inserted in each subjects, six fibres in each arm. Each fibre was perfused at a rate of 3 μL/min, and samples were collected in 2 min fractions. By the IPD technique, codeine was administrered to the skin by adding codeine to the perfusion medium. Sequential IPD challenges were performed in one arm. and ICTs were done on the other arm. Results Sixfold serial dilutions of codeine (0.01-3 mg/mL) caused a significant doserelated histamine release by ICT and IPD. Peak histamine release was found within the first 4 min after skin challenge by ICT and IPD, followed by a fast decline with a dialysate histamine half life of approximately 2-3 min. Peak hisamine release was linearly correlates with cumulative release of the 20 min sampling period, and histamine release correlated with weal soze. The coefficient of variation on peak histamine releae was 18.9% and 4.8% for codeine ICT and IPD, respectively. Conclusioin We have described in detail codeine-induced histamine release in intact human skin in vivo by the microdialysis technique. It was possible to administer codeine atraumaticallyl to the skin by intraprobe delivery. The skin microdialysis codeine atraumaticallly to the skin by intraprobe delivery. The skin microdialysis technique opens up possibilities for measurement of infllammatory mediators release in normal and diseases skin, and it will be possible to deliver immunopharmacologically active drugsto the skin by intraprobe delivery.  相似文献   
3.
目的 探讨外科手术切口病因及预防措施.方法 回顾分析我科自2001年5月~2005年7月施行大、中手术后发生切口脂肪液化的60例病例.结果 肥胖,术中皮下脂肪层使用电刀,术中切口器械挤压时间长,大块组织钳夹,老年人、糖尿病等可引发切口脂肪液化.结论 手术切口脂肪液病因较多,肥胖、术中使用电刀、器械挤压时间长、老年人糖尿病均为重要影响因素.  相似文献   
4.
Summary The release of endogenous catecholamines in aorto-coronary bypass graft patients receiving either 0.5 mg/kg enoximone (n=10), 4.0 mg/kg theophylline (n=10) or saline solution (control,n=10) has been studied, as well as certain haemodynamic parameters. Adrenaline (A) and noradrenaline (NA) concentrations were not significantly changed by the administration of enoximone. Theophylline caused a small increase in NA (+ 40% in the 1st min) and a marked increase in A (approximately + 7000% in the 1st min), which still remained elevated at the end of the investigation period (+ 220% in the 30th min). The major haemodynamic effects of enoximone were a significant increase in cardiac index (CI; + 35%) and a decrease in pulmonary capillary wedge pressure (PCWP; −27%), pulmonary artery pressure (PAP; −21%), RVEDV and RVESV, while the heart rate (HR) remained almost unchanged. The dominant haemodynamic effects of theophylline were an increase in HR (+ 26%; arrhythmia in 3 patients), PAP (+ 22%), and RVEDV (+ 19%), while REVESV (+ 26%), MAP (−16%), CI (−14%), and RVEF (−15%) fell significantly. It is concluded that the haemodynamic actions of enoximone are not mediated by catecholamine release, whereas the adverse cardiovascular effects of theophylline might partly be explained by the significant increase in plasma adrenaline.  相似文献   
5.
Mentosternal contractures still represent a surgical challenge due to their prominent position. They require early operative treatment for both function and aesthetic reasons. Careful clinical examination of scar position and traction forces, both at rest and when functioning, in addition to proper evaluation of the surrounding soft tissue are mandatory for precise preoperative planning of the required reconstruction. In general, the technically most feasible operation is favored if the functional and aesthetic results are good and postoperative risk for recurrence is low. Between 1987 and 1994, 21 patients with cervical, mentosternal, and mentothoracic contractures were operated upon. Eight patients were reconstructed with local flaps and 13 with microvascular free flaps.  相似文献   
6.
Cavernous angiomas, also called cavernous malformations or cavernomas, are vascular hamartomas accounting for 3–16% of all angiomatous lesions of the spinal district. Although histologically identical, these vascular anomalies may exhibit different clinical behavior and radiological features, depending on their location, hinting at different managements and therapeutic approaches. The authors report 11 cases of symptomatic spinal cavernous angiomas diagnosed and surgically treated over the past 18 years. Age of patients ranged from 15–75 years; males outnumbered females. Three patients had vertebral cavernous malformations, secondarily invading the epidural space; two had pure epidural lesions; two patients had intradural extramedullary lesions, and four intramedullary lesions. Surgical removal was completely achieved in four patients with intramedullary lesions, in two with subdural extramedullary lesions, and in one with a pure epidural lesion. Subtotal excision of another one epidural and three vertebral cavernous angiomas was followed by radiotherapy. There was no morbidity related to surgery; the mean follow-up was 2 years. The outcome was excellent in two cases, good in six, and unchanged in the other three. The authors discuss the different modalities of treatment of these vascular lesions variously placed along the spine.  相似文献   
7.
BACKGROUND: Specific immunotherapy with intact allergen vaccine is a well-documented treatment for allergic diseases. Different vaccine formulations are currently commercially available, the active ingredient either being intact allergens or chemically modified allergoids. The rationale behind allergoids is to decrease allergenicity while maintaining immunogenicity. However, data from the German health authorities based on reporting of adverse events over a 10-year period did not indicate increased safety of allergoids over intact allergens. OBJECTIVE: The objective of this study was to investigate the effect of chemical modification on allergenicity and immunogenicity comparing four commercial allergoid products for birch pollen immunotherapy with an intact allergen vaccine. METHODS: Solid-phase IgE inhibition and histamine release assays were selected as model systems for allergenicity, and a combination of human T cell proliferation and IgG titres following mouse immunizations were used to address the immunogenicity of the intact allergen vaccine and the four allergoids. In all assays, the products were normalized with respect to the manufacturer's recommended maintenance dose. RESULTS: IgE inhibition experiments showed a change in epitope composition comparing intact allergen vaccine with allergoid. One allergoid product induced enhanced histamine release compared to the intact allergens, while the other three allergoids showed reduced release. Standard T cell stimulation assays using lines from allergic patients showed a reduced response for all allergoids compared with the intact allergen vaccine regardless of the cell type used for antigen presentation. All allergoids showed reduced capacity to induce allergen-specific IgG responses in mice. CONCLUSION: While some allergoids were associated with reduced allergenicity, a clear reduction in immunogenicity was observed for all allergoid products compared with the intact allergen vaccine, and the commercial allergoids tested therefore do not fulfil the allergoid concept.  相似文献   
8.
9.
BACKGROUND: Allergoids are widely used in specific immunotherapy (SIT) for the treatment of IgE-mediated allergic diseases, but all techniques for standardization of conventional allergic extracts may not be appropriate for standardization of a glutaraldehyde (GA)-modified extract because of the unique characteristics of these extracts. OBJECTIVE: To assess an accurate methodology for standardization of chemically modified extracts. METHODS: GA-modified extracts from Parietaria judaica pollen were purified by diafiltration. Biochemical properties were investigated by determination of amino groups, chromatography, and SDS-PAGE. The IgE-binding activity was determined by skin prick test, enzyme allergosorbent test inhibition, basophil activation, and histamine release tests. Peripheral blood mononuclear cells (PBMCs) from P. judaica pollen-allergic subjects were stimulated with either native or allergoid extracts, and proliferation was measured. RESULTS: Biochemical data indicated a high degree of allergen polymerization resulting in extract components higher than 100 kDa. IgE-binding activity, both in vivo and in vitro, was reduced by more than 99.8%. Both allergen and allergoid induced PBMC proliferation and synthesis of blocking IgG antibodies at similar rates. Moreover, no evidence of introduction of new determinants by chemical modification was found. CONCLUSIONS: The preparation of GA-modified extracts by diafiltration is faster and more reliable than previous chromatographic methods. These modified extracts have drastically reduced their allergenicity while maintaining their immunogenicity, and therefore they can be used in safer and shortened schedules of SIT.  相似文献   
10.
Summary To determine if acute or chronic (21 days) losartan (10mg/kg, s.c.) regulates the renin-angiotensin system in interscapular brown adipose tissue, angiotensin II (AII) content and [3H]overflow from slices preloaded with [3H]norepinephrine were examined. Acute or chronic losartan administration had no effect on AII content. AII increased evoked [3H]overflow from slices from control rats. Losartan administration did not alter basal [3H]outflow or evoked [3H]overflow. Acute losartan administration inhibited AII-induced enhancement of evoked [3H]overflow. Tolerance developed to the inhibitory effect of losartan following chronic administration.Supported by a grant from the American Heart Association (Local Kentucky Affiliate) and by a gift from DuPont Merck Pharmaceuticals. Portions of this work have been presented in abstract form [The Pharmacologist 34(3): 157, 1992]  相似文献   
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