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991.
BACKGROUND: Clinical documentation about effects on local markers of inflammation of sublingual immunotherapy (SLIT) in children is still poor. METHODS: Twenty-four children (age range 4-16 years, average 8.5 years) monosensitized to house dust mites (HDMs) were randomized to receive active or placebo SLIT for this allergen according to a double-blind, placebo-controlled design. Before treatment and 10-12 months later the following parameters were checked: ECP and tryptase in sputum and nasal secretion, serum and nasal mite-specific IgE (sIgE), allergen-specific nasal challenge test (sNCT), nasal symptoms and tryptase after sNCT. RESULTS: Nasal tryptase and nasal IgE in basal conditions were unchanged in treated children but significantly increased in untreated children (P = 0.0156 and P = 0.0313, respectively). The threshold for sNCT was unchanged in both groups of children, but the symptom score after sNCT was unchanged in the placebo group and significantly decreased in the active group (P = 0.0084). The nasal tryptase after sNCT was unchanged in the active group and significantly increased in the placebo group (P = 0.0218). Intergroup comparison showed a significant difference in oral tryptase and nasal tryptase after sNCT in favour of the active group. CONCLUSIONS: These interim results after only 1 year of treatment show that SLIT in children monosensitized to HDMs is able to avoid the spontaneous increase in both nasal sIgE antibodies and in local allergic inflammation in basal conditions. These outcomes are confirmed and supported by the decrease of symptoms in the active group combined with the increase of nasal tryptase only in the control group in both cases after sNCT. 相似文献
992.
目的利用基因打靶技术构建变异链球菌葡聚糖结合蛋白D基因(gbpD)失活株,用于葡聚糖结合蛋白D基因功能的研究.方法体外培养变异链球菌UA159菌株并以其基因组为模板,对gbpD基因内部序列进行PCR扩增,连接自杀载体pVA8912,分别用酶切及PCR鉴定;转化变异链球菌UA159株,用PCR及Western blot鉴定.结果经鉴定PCR产物及插入片段大小与预期值相符,且为所需目的基因片段,成功构建了自杀质粒pVA8912-gbpD;经PCR鉴定及Western blot鉴定,gbpD基因失活株基因组中gbpD基因内部成功插入目的片段,且该菌株不表达GbpD蛋白.结论成功构建了用于变异链球菌gbpD基因打靶的自杀质粒和gbpD基因失活株,为该基因功能的研究奠定了基础. 相似文献
993.
目的研究路氏乳杆菌(Lactobacillus reuteri,也称罗伊氏乳杆菌)JCM1081菌体表面蛋白对其黏附HT-29细胞的影响。方法将路氏乳杆菌JCM1081菌体进行胰蛋白酶、蛋白酶K处理;用氯化锂和盐酸胍对乳杆菌表面的蛋白进行抽提,进行SDS-PAGE后与黏蛋白受体进行Western blot,并对杂交阳性蛋白进行质谱分析鉴定。结果路氏乳杆菌JCM1081菌体经胰蛋白酶、蛋白酶K处理后,其对HT-29细胞的黏附力显著下降(P<0.01);用氯化锂去除路氏乳杆菌JCM1081菌体外表面的S层蛋白后,路氏乳杆菌JCM1081对HT-29细胞的黏附力无显著变化;Western blot结果显示相对分子质量(Mr)为29×103和14×103的两种菌体表面蛋白与黏蛋白受体杂交中出现了强阳性;质谱分析结果显示29×103蛋白与路氏乳杆菌ATCC55730的h0793蛋白相似性高达71.1%。结论路氏乳杆菌JCM1081菌体表面的蛋白参与了乳杆菌的黏附,其中29×103和14×103的两种胞壁表面蛋白能够特异地识别黏蛋白受体并与之结合,29×103蛋白属ABC转运蛋白家族。 相似文献
994.
Dendrites and spines undergo dynamic changes in physiological and pathological conditions. Dendritic outgrowth has been observed in surviving neurons months after ischemia, which is associated with the functional compensation. It remains unclear how dendrites in surviving neurons are altered shortly after ischemia, which might reveal the mechanisms underlying neuronal survival. Using primary cortical cultures, we monitored the dendritic changes in individual neurons after oxygen-glucose deprivation (OGD). Two to four hours of OGD induced approximately 30–50% cell death in 24 h. However, the total dendritic length in surviving neurons was significantly increased after OGD with a peak at 6 h after re-oxygenation. The increase of dendritic length after OGD was mainly due to the sprouting rather than the extension of the dendrites. The dendritic outgrowth after 2 h of OGD was greater than that after 4 h of OGD. Application of NMDA receptor blocker MK-801 abolished OGD-induced dendritic outgrowth, whereas application of AMPA receptor antagonist CNQX had no significant effects. These results demonstrate a NMDA receptor-dependent dendritic plasticity shortly after OGD, which provides insights into the early response of surviving neurons after ischemia. 相似文献
995.
The cholesteryl ester transfer protein (CETP) locus as a candidate gene in abdominal aortic aneurysm
Dorothy Ramsbottom Anne O'Neill Donna M. Sexton Rafael A. Gafoor David Bouchier-Hayes David T. Croke 《Clinical genetics》1997,51(4):241-245
Abdominal aortic aneurysm (AAA) is a relatively common disease of the elderly presenting as progressive dilatation of the abdominal aorta. The condition shows a pronounced tendency to cluster in families, indicating a genetic component in the disease aetiology. We have screened the cholesteryl ester transfer protein (CETP) gene, which has been proposed as a candidate gene in AAA, by means of SSCP, DNA sequencing and restriction analysis in a cohort of patients with AAA and a matching control group drawn from the Irish population. The analysis has demonstrated sequence variation at four sites in the CETP gene: an A-T transversion in exon 9 (producing a Lys309-Stop codon substitution), a G-A transition in exon 14 (producing a conservative Va1421-Ile substitution), a C-T transition in intron 12 and a G-A transition in intron 15. None of the last three sites corresponded with sites of functional significance in the protein, suggesting that this reflects neutral polymorphism at the CETP locus. Furthermore, the frequencies of these four polymorphisms in the AAA patient and control groups were not significantly different. These data therefore suggest that CETP may be excluded as a candidate gene in abdominal aortic aneurysm. 相似文献
996.
Tim H.-M. Huang Diane Peckham Jacqueline R. Batanian Matthew B. Martin Melissa Kouba Charles W. Caldwell Judith H. Miles 《Clinical genetics》1994,46(4):299-303
We describe two brothers and a cousin with common clinical features, including mild mental retardation, motor delays, hypotonia with truncal ataxia, esotropia, and mild facial and hand dysmorphia. The initial routine chromosome study failed to detect any abnormality in the proband. Based on a high index of clinical suspicion, high-resolution chromosome studies were performed on the proband's parents. A small reciprocal translocation t(10;14) (q26.1;q32.3) was detected in the father. The breakpoint on the derivative chromosome 14 was further placed telomeric to the immunoglobulin heavy-chain gene cluster at the band q32.33 by fluorescence in situ hybridization. Studies of the proband and two affected paternal cousins revealed that each had inherited the same derivative chromosome 10 from their carrier parents. This unbalanced karyotype resulted from an adjacent-1 segregation of the 10;14 translocation. 相似文献
997.
Individual specific antigenic rubella virus (RV) structural proteins are required for accurate serological diagnosis of acute and congenital rubella infections as well as rubella immune status. The RV envelope glycoprotein E1 is the major target antigen and plays an important role in viral-specific immune responses. The native virion is difficult to produce in large quantities and the protein subunits are also difficult to isolate without loss of antigenicity. The production of a soluble RV E1 (designated E1ΔTm) using the baculovirus-insect cell expression system is described. In contrast to wild-type RV E1, the genetically engineered E1ΔTm protein lacks a transmembrane anchor. It behaved as a secretory protein and was secreted abundantly from insect cells. Pulse-chase studies were used to examine the synthesis, glycosylation, and secretion of E1ΔTm by the insect cells. The secreted E1ΔTm protein was purified from serum-free medium by onestep immunochromatography. The purified E1ΔTm protein retained full antigenicity and may be a convenient source of E1 protein for use in diagnostic assay and rubella vaccine development. 相似文献
998.
999.
鼻咽癌转移相关的分泌蛋白质的筛选 总被引:2,自引:0,他引:2
目的:筛选鼻咽癌(nasopharyngeal carcinoma, NPC)转移相关的分泌蛋白质,为阐明NPC转移机制以及筛选NPC转移分子标志物提供实验依据。方法:应用二维凝胶电泳(two-dimensional electrophoresis,2-DE)技术分离一对来自同一亲本,具有不同转移潜能的NPC细胞系5-8F和6-10B细胞的分泌蛋白质,图像分析识别差异表达的蛋白质点,基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)和电喷雾-四极杆-串联质谱(ESI-Q-TOF MS/MS)对差异表达的蛋白质点进行鉴定。Western印迹法检测差异分泌蛋白质nm23-H1在两株细胞中的表达水平。结果:建立了5-8F和6-10B分泌蛋白质的2-DE图谱,质谱分析鉴定出14个非冗余的分泌蛋白质,其中Oncoprotein18等蛋白质在高转移潜能NPC细胞系5-8F中的表达水平高于无转移潜能的NPC细胞系,而nm23-H1等蛋白质在5-8F细胞系中的表达水平低于6-10B细胞系。Western印迹分析证实了nm23-H1在5-8F和6-10B细胞分泌蛋白质中的差异表达水平。结论:所鉴定的14个非冗余的差异分泌蛋白质为研究NPC转移机制以及筛选NPC转移分子标志物提供了实验依据。 相似文献
1000.
Amyloid enhancing factor (AEF), which has recently been shown to have identity with ubiquitin (Ub), is believed to play a causative role in experimentally induced AA amyloidosis in mice. We have examined the profile of Ub in activated leukocytes and splenic reticulo-endothelial (RE) cells and its relationship with serum amyloid A protein (SAA) and AA amyloid deposits in an alveolar hydatid cyst (AHC)-infected mouse model of AA amyloidosis. Two monospecific antibodies, anti-ubiquitin (RABU) and anti-mouse AA amyloid, were used as immunological probes to localize Ub, SAA, and AA amyloid. In response to AHC infection, the dull and diffuse Ub immunoreactivity in normal mouse leukocytes and RE cells promptly changed to a discrete granular pattern suggesting an increase in the intracellular concentration of Ub and the formation of Ub-protein conjugates. This corresponded to an elevation in SAA levels, SAA uptake by RABU-positive phagocytic cells, co-localization of Ub-SAA immunoreactive splenocytes in the perifollicular areas, and deposition of Ub-bound AA amyloid in the splenic and hepatic tissues. These results suggest that Ub-loaded monocytoid cells may play an important role in the physiological processing of the sequestered SAA into AA amyloid. Aspects of AA amyloidogenesis are discussed in relation to other experimental models in which stress-induced Ub-protein conjugate formation and its transport to lysosomal vesicles have been studied. 相似文献