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41.
BACKGROUND: Buckwheat flour (BF) is known as a potent food allergen. Sensitization to it usually occurs by ingestion but also by inhalation in occupational or domestic exposure. Buckwheat chaff-stuffed pillows (BCP) can be contaminated with BF during the process of pilling, and many Korean children and adults use BCP for health reasons. METHODS AND RESULTS: We here present three cases of BF allergy in children using BCP, who had been treated as nonatopic asthmatics after undergoing the routine allergy skin tests and serologic tests. We took careful clinical histories, and performed skin prick tests (SPT), the radioimmunoassay (RIA) for specific IgE, the BCP-elimination test, the BF bronchial provocation test, and IgE Western blot. All three children showed positive skin reactions to BF, but none of them had positive reactions to house-dust mites. Nocturnal asthmatic symptoms were improved during 7 days of BCP elimination, and asthmatic responses were observed by bronchial provocation tests with homemade BF extract. Serum BF-specific IgE antibodies and several IgE-binding proteins were detected by RIA and Western blot analysis, respectively. CONCLUSIONS: Thus, a small amount of BF attached to BCP can induce BF sensitization, and BCP should be considered a main cause of childhood nocturnal asthma in those asthmatics exposed to these pillows. 相似文献
42.
Joannis Theodorou Martine Raphaël Claude Bigorgne Christine Fourcade Chantal Lahet Gilles Cochet Marie-Paule Lefranc Philippe Gaulard Jean-Pierre Farcet 《The Journal of pathology》1994,174(4):233-242
The recombination events of the γ and β T-cell receptor (TCR) loci were analysed in a series of 39 peripheral T-cell lymphomas (PTCLs) in association with the expression of TCR chains. In TCR αβ PTCLs, 22/23 cases showed a γ-gene rearrangement while only 18/23 showed a concomitant β-gene rearrangement. The germline configuration of the β locus was found in angioimmunoblastic lymphadenopathy and lymphoepithelioid lymphomas. Three γδ PTCLs rearranged both γ and β genes. TCR silent PTCLs showed three different patterns of γ- and β-gene rearrangements. Three cases were in germline configuration for both loci; five cases had a rearranged γ and a germline β locus; and five cases had the two loci rearranged. Regarding the variable genes in the γ-rearranged alleles, members of the VγI subgroup were the most frequently presented (39/50), followed by VγII, VγIII, and VγIV (9/50, 1/50, and 1/50, respectively). Joining segment usage was as follows: J1 or J2 (32/50), JP1 or JP2 (17/50), and JP (1/50). Taken together, these data demonstrate that the γ locus is more frequently rearranged whatever the TCR expression. The γ-locus analysis provides a better diagnostic yield than the β locus in the study of PTCL clonality. 相似文献
43.
A blocking ELISA was developed to confirm the specificity of screening tests for anti-HIV-1 antibodies. A murine monoclonal antibody (McAb) raised against recombinant gp160 was used in combination with a commercial technique (ELA-VIA-1). After determining the optimal experimental conditions, the assay was applied to 92 samples presenting different reactivities by Western blot (WB) analysis. All the sera containing antibodies to gp160/gp120 (53) were positive in our assay. The six patients who sero converted showed a low positivity by ELAVIA-1 (optical density near the cutoff value) reacted by blocking-ELAVIA-1 with an McAb binding inhibition greater than 85%. By contrast, negative samples (29) and specimens that exhibited reactivity only against gag-proteins (10) were not detected (McAb binding inhibition smaller than 15%). This sensitive and specific blocking-ELAVIA-1 represents a convenient alternative to WB as a confirmatory test. The technique is time-saving and inexpensive and can easily be integrated with a screening test for diagnostic or epidemiologic studies on HIV-1 infection. 相似文献
44.
缺氧预适应小鼠脑组织中缺氧诱导因子-1的表达 总被引:2,自引:0,他引:2
为探讨缺氧诱导因子 1 (HIF 1 )在缺氧预适应小鼠脑组织中的表达 ,用Western印迹法检测慢性缺氧 (H)和不缺氧 (C)HeLa细胞、急性重复性缺氧 0次 (H0 )、1次 (H1)、4次 (H4 )小鼠脑组织中的HIF 1α。结果 :慢性缺氧HeLa细胞中可检测到较多的HIF 1α,H0 组脑组织中检测不到HIF 1α ,H1组检测到微量HIF 1α,H4 组检测到较多HIF 1α。结果显示 :脑组织中HIF 1α的含量随缺氧预适应的产生而逐步增加 ,提示HIF 1可能参与缺氧预适应的形成。 相似文献
45.
L-NAME对肝硬化大鼠胃肠道中一氧化氮合酶亚型表达的影响 总被引:6,自引:3,他引:3
目的 研究一氧化氮合酶亚型(NOS1,NOS2,NOS3)在肝硬化大鼠胃肠道中的表达,并探讨NOS抑制剂左旋硝基精氨酸甲基酯(L-NAME)对其表达的影响。方法 制作大鼠四氯化碳中毒肝硬化模型,肝硬化模型大鼠随枘发为NO合酶(NOS)抑制剂治疗组和未治疗组,模型治疗组用L-NAME0.5mg.kg^-1.d^-1,胃内注入,每日1次,治疗10d,免疫组织化学染色显示胃肠道组织中型NOS的染色强度和分布,Western blot法检测胃肠道组织中各型NOS的表达。结果 模型组大鼠胃、小肠、结肠组织 的NOS染色强度显著弱于正常对照组和L-NAME治疗组大鼠。Western blot显示在肝硬化模型大鼠胃、小肠、结肠组织中的各型NOS表达均明显降低,L-NAME治疗后又恢复至接近正常。结论 肝硬化大鼠胃肠道组织中各型NOS的表达明显减少,L-NAME对其表达有调节作用。 相似文献
46.
47.
8—Br—cAMP对人视网膜母细胞瘤HXO—Rb44细胞癌基因的表达效应 总被引:2,自引:2,他引:0
目的 研究8-Br-cAMP对培养的人视网膜母细胞瘤HXO-Rb44细胞癌基因表达的效应及其与该细胞生长的关系。方法 c-fos mRNA,N-myc mRNA及p21ras mRNA均以原位杂交RNA斑点印迹技术检测,对繁殖细胞核抗原,v-Fos,N-Myc和P^21ras蛋白表达的免疫反应性则采用免疫组化及收白质斑点印迹技术检测。 相似文献
48.
49.
Cadiou H Sienaert I Vanlingen S Parys JB Molle G Duclohier H 《The European journal of neuroscience》2000,12(8):2805-2811
In addition to the activation of cAMP-dependent pathways, odorant binding to its receptor can lead to inositol 1,4,5-trisphosphate (InsP3) production that may induce the opening of plasma membrane channels. We therefore investigated the presence and nature of such channels in carp olfactory cilia. Functional analysis was performed by reconstitution of the olfactory cilia in planar lipid bilayers (tip-dip method). In the presence of InsP3 (10 microM) and Ca2+ (100 nM), a current of 1.6 +/- 0.1 pA (mean +/- SEM, n = 4) was measured, using Ba2+ as charge carrier. The I/V curve displayed a slope conductance of 45 +/- 5 pS and a reversal potential of -29 mV indicating a higher selectivity for divalent cations. This current was characterized by two mean open times (3.0 +/- 0.4 ms and 42.0 +/- 2.6 ms, n = 4) and was strongly inhibited by ruthenium red (30 microM) or heparin (10 microg/mL). Importantly, the channel activity was closely dependent on the Ca2+ concentration, with the highest open probability (Po) at 100 nM Ca2+ (Po = 0.50 +/- 0.02, n = 4). Po is lower at both higher and lower Ca2+ concentrations. A structural identification of the channel was attempted by using a large panel of antibodies, raised against several InsP3 receptor (InsP3R)/Ca2+ release channel isoforms. The type 1 InsP3R was detected in carp cerebellum and whole brain, while a lower molecular mass InsP3R, which may correspond to type 2 or 3, was detected in heart, whole brain and the soma of the olfactory neurons. None of the antibodies, however, cross-reacted with olfactory cilia. Taken together, these results indicate that in carp olfactory cilia an InsP3-dependent channel is present, distinct from the classical InsP3Rs localized on intracellular membranes. 相似文献