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51.
Bousquet J Yssel H Demoly P 《BioDrugs : clinical immunotherapeutics, biopharmaceuticals and gene therapy》2000,13(1):61-75
AbstractAllergen-specific immunotherapy is widely used to treat allergic diseases, andcurrent research is now focusing on the development of therapeutic vaccines actingon the IgE immune response following allergen challenge. The IgE immuneresponse is dependent on genetic and environmental factors; production of IgEresults from complex interactions among B cells, T cells, mast cells, basophils,surface and adhesion molecules and various cytokines. New vaccination methods under investigation involve allergen-specific ornonspecific methodology. Allergen-specific methods currently being developedinclude allergoids, passive saturation of effector cells, plasmid DNA immunisationand antigen-antibody complexes. The mechanisms of immunotherapy usingallergen-specific methods differ with the allergens and the route of immunisationused (parenteral, intranasal, sublingual, oral or bronchial). Many vaccines beingdeveloped at present comprise synthetic, recombinant or highly purified subunitantigens, which although they have increased safety may also be less immunogenic.It is hoped that the addition of adjuvants will overcome this drawback. Methods ofincreasing the dose of allergen while reducing the possibility of an anaphylacticreaction include the use of non-anaphylactic isoforms of the allergens, alteration ofthe tertiary structure of the allergens and construction of minimal allergen-derived Tcell peptides. Nonspecific approaches include humanised anti-IgE antibodies,moderation of the T(H)2 cytokine network and antisenseoligodeoxynucleotide therapy. 相似文献
52.
McGlinchey PG Spence MS Patterson CC Allen AR Murphy G Fogarty D Evans A McKeown PP 《Disease markers》2004,20(6):289-294
Matrix metalloproteinase-3 (MMP-3) has been proposed as an important mediator of the atherosclerotic process. The possible role of the functional -1612 5A/6A polymorphism of the MMP-3 gene in the susceptibility to ischaemic heart disease (IHD) was investigated in a well-defined Irish population using two recently described family based tests of association. One thousand and twelve individuals from 386 families with at least one member prematurely affected with IHD were genotyped. Using the combined transmission disequilibrium test (TDT)/sib-TDT and the pedigree disequilibrium test (PDT), no association between the MMP-3 -1612 5A/6A polymorphism and IHD was found. Our data demonstrate that, in an Irish population, the MMP-3 -1612 5A/6A polymorphism is not associated with IHD. 相似文献
53.
Paul Fréneaux Claude Nos Anne Vincent-Salomon Pascal Genin Brigitte Sigal-Zafrani Abir Al Ghuzlan Marie-José Birolini Krishna Clough Xavier Sastre-Garau 《Modern pathology》2002,15(6):641-646
There is no consensus method for the histological analysis of axillary sentinel nodes (SN). This study aimed to (1) assess the rate of occult metastases in SN using large serial sectioning and immunohistochemistry (IHC), (2) evaluate whether occult metastases were predictive of metastases in the downstream axillary nodes, and (3) specify a methodology of analysis of SN that could be both sensitive and applicable in daily practice. One hundred three patients with breast carcinoma underwent SN biopsy and then axillary dissection. SN free of tumor at standard examination of one section were sectioned at six levels (150-microm intervals) and immunostained for cytokeratin. The number and localization of labeled metastatic cells (occult metastases) were recorded. In 29 of the 103 patients (28%), SN were found to be metastatic after standard examination. The SN of the remaining 74 patients were further analyzed using IHC. Occult metastases were detected in 35 of these patients (47.3%), leading to an overall SN involvement rate of 62% (29+35/103). In 33 of these 35 cases, the plurality and the dispersion of the immunostained cells implied that the screening of only 3 of the 6 levels would have led to the detection of diagnostic positive events. Only one of the 35 patients (2.8%) with occult metastases showed metastatic lymph node in the downstream axilla. In our series of axillary SN, the analysis of one standard histologic section and, when negative, of only three additional sections after IHC revealed >60% of metastasis or occult metastasis. Metastasis detected by standard analysis had a high predictive value of downstream node metastasis, whereas the predictive value of occult metastasis revealed by IHC was poor. The clinical significance of occult metastases in SN needs to be specified by long-term follow-up analysis. 相似文献
54.
Hemodynamic modes of ventricular assist with a rotary blood pump: continuous, pulsatile, and failure
Vandenberghe S Segers P Antaki JF Meyns B Verdonck PR 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2005,51(6):711-718
Pulsatile operation of rotary blood pumps (RBPs) has received interest due to potential concern with nonphysiological hemodynamics. This study aimed to gain insight to the effects of various RBP modes on the heart-device interaction. A Deltastream diagonal pump (Medos Medizintechnik GmbH) was inserted in a cardiovascular simulator with apical-to-ascending aorta cannulation. The pump was run in continuous mode with incrementally increasing rotating speed (0-5000 rpm). This was repeated for three heart rates (50-100-150 bpm) and three levels of left ventricular (LV) contractility. Subsequently, the Deltastream was run in pulsatile mode to elucidate the effect of (de)synchronization between heart and pump. LV volume and pressure, arterial pressure, flows, and energetic parameters were used to evaluate the interaction. Pump failure (0 rpm) resulted in aortic pressure drops (17-46 mm Hg) from baseline. In continuous mode, pump flow compensated by diminished aortic flow, thus yielding constant total flow. High continuous rotating speed resulted in acute hypertension (mean aortic pressure up to 178 mm Hg). In pulsatile mode, unmatched heart and pulsatile pump rates yielded unphysiologic pressure and flow patterns and LV unloading was found to be highly dependent on synchronization phase. Optimal unloading was achieved when the minimum rotating speed occurred at end-systole. We conclude that, in continuous mode, a perfusion benefit can only be achieved if the continuous pump flow exceeds the preimplant (baseline) cardiac output. Pulsatile mode of support results in complex pressure and volume variations and requires accurate triggering to achieve optimal unloading. 相似文献
55.
Increased Immunostaining of Fibulin-1, an Estrogen-Regulated Protein in the Stroma of Human Ovarian Epithelial Tumors 总被引:1,自引:1,他引:1 下载免费PDF全文
Pascal Roger Pascal Pujol Annick Lucas Pierre Baldet Henri Rochefort 《The American journal of pathology》1998,153(5):1579-1588
Fibulin-1, an extracellular matrix protein, is secreted by human ovarian metastatic cancer cell lines under estrogen stimulation. Fibulin-1 expression was quantified by immunohistochemistry and computer-aided image analysis in 44 human ovarian epithelial tumors and 14 normal ovaries. The fibulin-1 staining intensity in proximal stroma, close to the surface of epithelial cells and tumor cells, progressively increased from normal ovaries to serous carcinomas. In all lesions, excluding cystadenomas, fibulin-1 accumulation was higher in proximal stroma than in distant stroma. In situ hybridization demonstrated strong fibulin-1 gene expression in epithelial cells of serous ovarian carcinomas and some cysts. The weak expression of fibulin-1 RNA in some stromal cells of these tumors could not explain the strong fibulin-1 protein accumulation in tumor stroma, which was therefore mostly produced by tumor epithelial cells. In carcinomas, fibulin-1 staining was not correlated with the percentage of estrogen receptor-α (ERα)-stained nuclei but was inversely correlated with the progesterone receptor. However, in cystadenomas and borderline tumors, both fibulin-1 and ERα protein levels increased, in comparison with normal ovaries, suggesting an effect of estrogens in the early steps of tumorigenesis. This fibulin-1 overexpression, demonstrated in vivo in ovarian carcinomas, might be a useful indicator for predicting cancer risk and/or aggressiveness. 相似文献
56.
57.
Tardivel A Tinel A Lens S Steiner QG Sauberli E Wilson A Mackay F Rolink AG Beermann F Tschopp J Schneider P 《European journal of immunology》2004,34(2):509-518
The TNF family ligand B cell-activating factor (BAFF, BLyS, TALL-1) is an essential factor for B cell development. BAFF binds to three receptors, BAFF-R, transmembrane activator and CAML interactor (TACI), and B cell maturation antigen (BCMA), but only BAFF-R is required for successful survival and maturation of splenic B cells. To test whether the effect of BAFF is due to the up-regulation of anti-apoptotic factors, TACI-Ig-transgenic mice, in which BAFF function is inhibited, were crossed with transgenic mice expressing FLICE-inhibitory protein (FLIP) or Bcl-2 in the B cell compartment. FLIP expression did not rescue B cells, while enforced Bcl-2 expression restored peripheral B cells and the ability to mount T-dependent antibody responses. However, many B cells retained immaturity markers and failed to express normal amounts of CD21. Marginal zone B cells were not restored and the T-independent IgG3, but not IgM, response was impaired in the TACI-IgxBcl-2 mice. These results suggest that BAFF is required not only to inhibit apoptosis of maturating B cells, but also to promote differentiation events, in particular those leading to the generation of marginal zone B cells. 相似文献
58.
59.
BACKGROUND: Cases of allergy to cooked potato in children have been reported, some with immediate and others with late reactions. The clinical effects of chronic allergic reactions to potato and the effectiveness of diet on such reactions have not been described previously. OBJECTIVE: We sought to evaluate the importance of cooked potato as an allergenic food in individual cases of atopy in children. METHODS: Eight atopic children were selected on the basis of suspicion of allergy to cooked potatoes: all had potato-specific IgE, 2 of 8 had experienced immediate allergic reactions, and 6 of 8 had eczema that improved with a potato-elimination diet (decrease in severity scoring of atopic dermatis [SCORAD] index of >50%). The patients were evaluated by using skin prick tests with homemade cooked and noncooked potato extracts and with a commercial extract and by using IgE immunoblots from SDS-PAGE patterns of potato extract. Seven patients were challenged with cooked potato. The control group consisted of 9 age-matched atopic children, 8 of them with eczema. RESULTS: The mean SCORAD index decreased from 43.3 before to 11.5 after elimination of potato from the diet. Potato CAP values ranged from 3.71 to greater than 100 kUa/L. Potato challenge results were positive in 7 of 7 patients. Skin prick test responses were positive for cooked potato extracts in 7 of 7 patients, for noncooked extracts in 7 of 7 patients, and for the commercial extract in 8 of 8 patients compared with in 0 of 9, 1 of 9, and 1 of 9 subjects in the control group, respectively. During immunoblotting, 8 of 8 patient sera recognized one or more protein bands compared with 0 of 9 control subject sera. CONCLUSION: Allergy to cooked potatoes is a cause of severe allergic disease, with immediate reactions and eczema in some atopic infants and young children. 相似文献
60.