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11.
Skamstrup Hansen K Vestergaard H Stahl Skov P Søndergaard Khinchi M Vieths S Poulsen LK Bindslev-Jensen C 《Allergy》2001,56(2):109-117
The aim of the study was to develop and evaluate different methods of double-blind, placebo-controlled food challenge (DBPCFC) with apple. Three different DBPCFC models were evaluated: fresh apple juice, freshly grated apple, and freeze-dried apple powder. All challenges were performed outside the pollen season and took place from 1997 to 1999. The freeze-dried apple material was characterized by means of leukocyte histamine release (HR), skin prick test (SPT), and immunoblotting experiments. The study population consisted of birch pollen-allergic patients with a history of rhinitis in the birch-pollen season and positive specific IgE to birch. For comparison of the DBPCFC models, 65 patients with a positive open oral challenge with apple were selected. In the characterization of the freeze-dried apple material, 46 birch pollen-allergic patients were included. The IgE reactivity to apple was evaluated by measurement of specific IgE, HR, and SPT. Golden Delicious apples were used in all experiments. The results of this study showed that it was possible to perform DBPCFC with apple in birch pollen-allergic individuals. The model with freshly squeezed apple juice had a low sensitivity and displayed a high frequency of reactions to placebo, probably due to the ingredients used for blinding. The sensitivity of the models with freshly grated apple and freeze-dried apple powder was 0.74/0.60. An increase in sensitivity is desirable. The freeze-dried apple powder proved to be useful for SPT, HR, and oral challenges, but further investigation of the stability and the allergenic profile of the material is needed. 相似文献
12.
T Hummelshoj U Bodtger P Datta H J Malling A Oturai L K Poulsen L P Ryder P S Sorensen E Svejgaard A Svejgaard 《European journal of immunogenetics》2003,30(5):355-359
Several studies indicate genetic involvement of Th2 cytokines in allergic diseases. Interleukin (IL)-13 has been mapped to the cytokine cluster on chromosome 5q31-33, which has been associated with atopic conditions. Recently, an association was reported between the T allele in a promoter polymorphism in the IL-13 gene (C to T exchange) at position -1055 and allergic asthma in a population study in the Netherlands. This observation was apparently confirmed in a case-control study using probands and spouses from a Dutch asthma family study, but the polymorphism in that study was reported to occur at position -1111. In the present study, we established that this polymorphism is located at position -1024 relative to the ATG translation initiation codon, and investigated whether it confers a genetic predisposition to atopic conditions and the Th1 condition multiple sclerosis (MS) in Caucasian subjects. We confirmed the association between the IL-13 -1024TT genoype and inhalation allergy (P = 2.4E-02). By combining the data from the three studies, we demonstrated a strong association (P = 1.09E-05) between the IL-13 -1024 marker and inhalation allergy. Furthermore, we showed for the first time that this association also exists in atopic dermatitis (P = 2.0E-02). No association with MS was found. 相似文献
13.
14.
A. Üner A.-M. Weinberg C. Poulsen Nautrup I. Kassianoff W. Lüdemann F. Schier P. Claus D. Berens v. Rautenfeld 《Surgical and radiologic anatomy : SRA》2002,23(6):383-387
Abstract Spontaneous lymphvascular reanastomosis (SLR) following small bowel transplantation in rats is of clinical relevance for the resorption of long chain fatty acids. Detailed morphological and molecular data concerning the process of lymphvascular reanastomosis are not available in the literature. In this study SLR was investigated using microradiology and scanning electron microscopy. Between the 8th and 21st postoperative days following transplantation SLR does not occur between the intestinal trunk of the transplant and the thoracic duct of the recipient. Instead, an indirect connection was observed between the inserted advential lymphatic vessels of the mesenteric artery and lymphatic vessels of the aorta or ductus deferens, which are connected with the thoracic duct. 相似文献
15.
16.
Monomeric immunoglobulin E stabilizes FcεRIα from the human basophil cell line KU812 by protecting it from natural turnover 总被引:2,自引:0,他引:2
B. M. Jensen J. B. Hansen S. Dissing† J. Gerwien‡ § P. S. Skov L. K. Poulsen 《Clinical and experimental allergy》2003,33(5):655-662
BACKGROUND: The high affinity IgE receptor (FcepsilonRI) on mast cells and basophils is up-regulated by its own ligand IgE; however, the mechanism is unknown. OBJECTIVE: To study the IgE-mediated effect on FcepsilonRI on basophils by using the human basophilic cell line KU812. METHODS: Expression of cell surface FcepsilonRI was assessed by flow cytometry. Western blot technique was used to illustrate tyrosine-phosphorylation and the Ca2+ level in KU812 was measured by fluorescence of Fura-2. Soluble specimens of the alpha-chain from FcepsilonRI (FcepsilonRIalpha) were obtained by lysing 107 KU812 pr. mL. FcepsilonRIalpha was detected by a sandwich immunoradiometric assay employing the IgE-binding capacity of FcepsilonRIalpha in conjunction with a monoclonal antibody. Polyclonal rabbit anti-FcepsilonRIalpha was used for detection of FcepsilonRIalpha by Western blotting. RESULTS: We found that monomeric IgE did not induce tyrosine-phosphorylation in KU812, which was the case when stimulating with IgE cross-linked by anti-IgE binding. Further, only cross-linking of IgE, but not monomeric IgE, increased the Ca2+ level. Using the immunoradiometric assay, we found a temperature dependent reduction in the amount of FcepsilonRIalpha. Samples incubated at 37 degrees C for 5 h displayed a 16-fold decrease in the FcepsilonRIalpha level compared with samples incubated at 4 degrees C. In the presence of IgE the reduction at 37 degrees C was only threefold. CONCLUSION: These results indicate that IgE does not induce intracellular signals in KU812, i.e., tyrosine-phosphorylation or Ca2+ release. Instead it appears that FcepsilonRIalpha is an unstable protein that IgE stabilizes and thereby protects from a temperature dependent turnover. 相似文献
17.
In a series of diploid abortion specimens with gross villous enlargement the parental origin was determined by chromosomal heteromorphisms, HLA typing, and enzyme analysis. Diploid androgenesis was the mechanism in 33 cases; in 28 cases the most likely origin was by duplication of a haploid sperm after fertilization of an anucleated ovum, whereas heteromorphisms in five cases indicated a dispermic origin. In one macroscopically complete molar specimen all marker techniques applied indicated a normal conception. In two homozygous specimens a second cell line with both maternal and paternal contributions indicated a twin gestation, whereas, in four conceptuses twinning was suggested solely by HLA determination or ultrasound scan. The observation of a heterogeneous origin of diploid moles, as indicated by three marker systems studied simultaneously, emphasizes that additional information about the frequency of different types of molar conceptions may be obtained by this approach. 相似文献
18.
45Ca2+ exchange and total calcium content were measured in isolated mouse pancreatic acini. 45Ca2+ uptake could be described as the sum of a constant and a single exponential kinetic component; about 60% of total acinar calcium was exchangeable. Stimulation by bethanechol increased 45Ca2+ uptake, but the time course of uptake could be fit only by the addition of a more rapid kinetic component without any change in the total exchangeable Ca2+. 45Ca2+ washout after 1-h loading could be fit as the sum of two exponential components. Stimulation increased the rate of 45Ca2+ washout with the appearance of a third and more rapid kinetic component. There was not, however, a good correspondence between the exponential constants measured in uptake and washout protocols in unstimulated acini. Exponential constants were also affected by the concentration of calcium in the medium, further indicating the presence of nonlinearities in 45Ca2+ exchange. The dose-response relationships were similar for bethanechol stimulation of 45Ca2+ uptake and amylase release, whereas stimulation of 45Ca2+ washout reached a maximum at a higher concentration of bethanechol. Both 45Ca2+ uptake and analytical measurement of total Ca2+ showed a rapid drop in acinar Ca2+ content followed by a gradual reuptake on stimulation by bethanechol. It is concluded that the initial primary effect of secretagogues is to increase Ca2+ efflux, which is interpreted to be the result of release of sequestered calcium into the cytosol. 相似文献
19.
5-Fluoro-2''-deoxyuridine induction of the fragile site on Xq28 associated with X linked mental retardation. 总被引:4,自引:1,他引:4 下载免费PDF全文
5-Fluoro-2'-deoxyuridine (FUdR) was found to be highly effective in inducing the heritable fragile site on Xq28 associated with mental retardation. Lymphocytes from two affected males manifested the fragile site in 30 to 40% of the mitoses when grown in the presence of FUdR. This observation suggests that depletion of the dTMP pool via thymidylate synthetase inhibition is responsible for the expression of the heritable fragile site on Xq28. 相似文献
20.
Highly toxic clone of Actinobacillus actinomycetemcomitans in geographically widespread cases of juvenile periodontitis in adolescents of African origin. 下载免费PDF全文
D Haubek K Poulsen J Westergaard G Dahln M Kilian 《Journal of clinical microbiology》1996,34(6):1576-1578
The bacterium Actinobacillus actinomycetemcomitans has been implicated in the pathogenesis of juvenile periodontitis as the etiologic agent on the basis of several lines of circumstantial evidence. A matter of extensive debate is whether A. actinomycetemcomitans is an exogenous contagious pathogen or an opportunistic pathogen that resides in the normal oral microflora. Here we show evidence of a single clone of A. actinomycetemcomitans isolated from multiple patients with juvenile periodontitis in members of families of African origin living in geographically widespread areas. The clone is characterized by a 530-bp deletion in the leukotoxin gene operon, resulting in a significantly increased production of leukotoxin. 相似文献