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81.
BACKGROUND: Diisocyanate asthma (DA) affects 2% to 10% of exposed workers, yet the pathogenetic mechanisms underlying this disorder remain ill defined. OBJECTIVE: To determine if specific single nucleotide polymorphisms (SNPs) of interleukin 4 receptor alpha (IL4RA), IL-13, and CD14 promoter genes are associated with DA. METHODS: Sixty-two workers with DA confirmed by specific inhalation challenge (SIC) and 75 diisocyanate-exposed, SIC-negative workers were analyzed for SNPs associated with IL4RA, IL-13, and CD14 promoter genes. RESULTS: No associations were found with individual SNPs and DA. When stratified according to specific diisocyanate exposure, a significant association was found between IL4RA (I50V) II and DA among individuals exposed to hexamethylene diisocyanate (HDI) (odds ratio [OR], 3.29; 95% confidence interval [CI], 1.33-8.14; P = .01) only. Similarly, the IL4RA (I50V) II and IL-13 (R110Q) RR combination was significantly associated with DA in HDI-exposed workers (OR, 4.13; 95% CI, 1.35-12.68; P = .01), as was the IL4RA (I50V) II and CD14 (C159T) CT genotype combination (OR, 5.2; 95% CI, 1.82-14.88; P = .002) and the triple genotype combination IL4RA (I50V) II, IL-13 (R110Q) RR, and CD14 (C159T) CT (OR, 6.4; 95% CI, 1.57-26.12; P = .01). CONCLUSIONS: Gene-environmental interactions may contribute to the pathogenesis of DA, and gene-gene interactions may modulate this relationship.  相似文献   
82.
The heat shock protein, hsp10, is an abundant protein in Mycobacterium tuberculosis (Mtb), its nucleotide sequence encoding a protein of 99 amino acids with a molecular mass of 10±7kD. This sequence is phylogenetically conserved, being represented by the GroES homologue of Escherichia coli. Hsp 10 and GroES are members of the chaperonin 10 family of molecular chaperones, and GroES is necessary for the optimal activity of GroEL, a member of the chaperonin 60 family and the E coli homologue of mycobacterial hsp65. Since hsp65 has been implicated in both experimental and human rheumatoid arthritis, we aimed to assess the immunomodulatory effects of its co-chaperonin, hsp10, in experimental arthritis. Our results show that an aqueous solution of a mycobacterial hsp10 delayed the onset and severity of adjuvant-induced arthritis in rodents when administered after disease induction but before joint involvement occurred. This biological activity was specific for the hsp10 of Mtb, since neither GroES nor the rat homologue was effective. Using synthetic hsp10 fragments, the activity was localized to the N-terminal region of the molecule. Assessment of circulating antibody levels to mycobacterial hsp10 and hsp65 indicated that all arthritic rats had increased litres to both hsp10 and hsp65: hsp10-treated rats showed further elevation of this humoral response not only to hsp10 but also to hsp65 when compared with the untreated arthritic control. This is the first report of the immunomodulatory activity of mycobacterial hsp10 in experimental arthritis, and exhibits a potential role for this co-chaperonin in pathophysiological situations.  相似文献   
83.
O'Goiman's (1979) criticisms of the orienting response (OR) significance hypothesis are not well-founded. The hypothesis is not based solely on electrodermal data—studies reporting significance effects for heart rate and pupillary OR are cited. The hypothesis does not discard novelty but suggests that an interaction between uncertainty and significance triggers OR. Differential reactivity across OR components reflects stimulus- and individual-response factors, and does not require separate “significance registers.” Since the hypothesis specifically maintains that appraisals of stimulus significance affect the OR, not the mere fact of cognitive appraisal per se, no general “cognitive appraisal effect” was ever expected. O'Gorman confuses the difficulty of estimating the subject's spontaneous judgments of significance with the relative ease of manipulating significance in the laboratory. He considers classic OR theory more “objective” only because he fails to look closely enough at the complex judgmental processes involved in stimulus intake, model building, and matching functions. O'Gorman's contentions of different initial- and test-ORs, and of a simple additive relationship between significance and OR, lack supportive data and are challenged by available evidence. Literature is cited suggesting that: a) scanning is continuously biased toward the detection of significant stimuli; b) detection of a sgnificant stimulus feature triggers increased information scanning, increasing the possibility that previously unrecognized uncertainty will be detected, and c) lowers the criterion level of the OR “threshold,” increasing the likelihood of OR if uncertainty is detected. Evidence is cited suggesting that the significance-OR, and perhaps attention in general, is mediated by neocortical-limbic interaction, the limbic' “motivational” evaluator of stimulus input steering and switching neocortical “intellectual” analyzers of stimulus pattern.  相似文献   
84.
There is renewed enthusiasm for exploring the possibility that Mycobacterium paratuberculosis may be causative in Crohn's disease (CD). We aimed to determine whether CD subjects are more likely to be M. paratuberculosis seropositive than controls. Using our population-based University of Manitoba Inflammatory Bowel Disease Research Registry, we recruited CD and ulcerative colitis (UC) subjects between 18 and 50 years of age for a study involving detailed questionnaires and venipuncture. We accessed the population-based databases of Manitoba Health (single provincial health insurer) to get age-, gender-, and geography-matched controls to our inflammatory bowel disease (IBD) population. We asked enrolling IBD subjects for potential nonaffected sibling controls. We used an enzyme-linked immunosorbent assay (ELISA) for serum antibodies to M. paratuberculosis initially developed for cattle but adapted for human use. The rate of positive ELISA results, based on previously published interpretation criteria, was significantly higher for all study groups. There was no difference in M. paratuberculosis seropositivity rate among CD patients (37.8%; n = 283), UC patients (34.7%; n = 144), healthy controls (33.6%; n = 402), and nonaffected siblings (34.1%; n = 138). For siblings, there was no correlation between M. paratuberculosis serological status and that of the corresponding IBD affected sibling. None of the demographic or questionnaire variables studied were predictive of M. paratuberculosis status. Subjects with CD and UC were less likely to have ingested unpasteurized milk and less likely to have had a non-tap water source as a primary water source. In conclusion, in this population-based case control study, the M. paratuberculosis seropositivity rate was approximately 35% for all groups and there was no difference in rates between CD patients, UC patients, healthy controls, or nonaffected siblings. The much higher rate of seropositivity for subjects from Manitoba, Canada, than for those from Denmark or Wisconsin cannot be obviously explained. While these data seem to refute any association of CD with M. paratuberculosis, the high seroprevalence in Manitobans raises the possibility that the high rates of CD in Manitoba could be related to high exposure rates for M. paratuberculosis. Hence, the possibility of an association between M. paratuberculosis and CD remains inconclusive.  相似文献   
85.
The differentiation of the urinogenital system and the appendicular skeleton in vertebrates is under the control of Hox genes. The common control of digit and gonad differentiation raises the possibility that patterns of digit formation may relate to spermatogenesis and hormonal concentrations. This work was concerned with the ratio between the length of the 2nd and 4th digit (2D:4D) in humans. We showed that (i) 2D:4D in right and left hands has a sexually dimorphic pattern; in males mean 2D:4D = 0.98, i.e. the 4th digit tended to be longer than the 2nd and in females mean 2D:4D = 1.00, i.e. the 2nd and 4th digits tended to be of equal length. The dimorphism is present from at least age 2 years and 2D:4D is probably established in utero; (ii) high 2D:4D ratio in right hands was associated with germ cell failure in men (P = 0.04); (iii) sperm number was negatively related to 2D:4D in the right hand (P = 0.004); (iv) in men testosterone concentrations were negatively related to right hand 2D:4D and in women and men LH (right hand), oestrogen (right and left hands) and prolactin (right hand) concentrations were positively correlated with 2D:4D ratio and (v) 2D:4D ratio in right hands remained positively related to luteinizing hormone and oestrogen after controlling for sex, age, height and weight.   相似文献   
86.
Exposure of rat hippocampal slices to perfusate containing 1-2 mM glutamate (GLU) induces reversible and relatively selective blockade of excitatory transmission. Intracellular recordings from 20 region CA1 hippocampal cells demonstrated only transient and mild effects on resting membrane properties and action potentials. In contrast, in 2 mM GLU excitatory postsynaptic potentials declined to 28% of control (P less than 0.001); inhibitory postsynaptic potentials remained robust at 88% of control. This suggests that excess exposure to GLU may result in a selective 'down-regulation' of excitatory synaptic transmission, while preserving inhibitory pathways. These observations may have practical implications for development of new anticonvulsant drugs.  相似文献   
87.
糖尿病大鼠心肌NF-κB、iNOS、COX-2表达的研究   总被引:2,自引:3,他引:2  
目的:观察核因子-κB(NF-κB)、诱导型一氧化氮合酶(iNOS)以及环氧化酶-2(COX-2)3种炎症因子在糖尿病大鼠心肌组织的表达。方法:30只SD大鼠随机分为正常对照组和糖尿病组,糖尿病组大鼠按60 mg/kg的剂量1次性腹腔注射链脲菌素。实验于24周末结束,观察2组大鼠的体重、平均血糖浓度、心重指数。并取心肌组织石蜡切片分别行NF-κB、iNOS和COX-2免疫组化染色。同时用凝胶电泳迁移率(EMSA)的方法测定心肌组织NF-κB活性。结果:(1)糖尿病大鼠心肌组织NF-κB阳性表达细胞明显多于对照组;(2)EMSA方法显示,糖尿病大鼠心肌组织NF-κB表达强度明显高于对照组;(3)对照组大鼠心肌组织未见iNOS的表达,糖尿病大鼠见明显iNOS的表达;(4)对照组大鼠心肌组织偶见COX-2的表达,糖尿病大鼠见明显COX-2的表达。结论:NF-κB、iNOS和COX-2在糖尿病大鼠心肌组织中表达活性明显增强。  相似文献   
88.
C基因截短的HBV复制与包装   总被引:1,自引:0,他引:1  
目的 探讨C基因截短型HBV变异体的复制与包装。方法 采用分子克隆、人工定点突变等技术构建C基因截短型HBV变异体质粒,用脂质体法转染HepG2细胞,提取细胞内及培养上清液中DNA分别进行Southem杂交,PCR及实时定量荧光PCR分析。结果 经DNA测序及酶切鉴定证实C基因截短型HBV质粒载体构建成功;C基因截短型HBV为复制缺损型,与辅助质粒共转染HepG2细胞,可在细胞内及培养上清液中检测到HBV各种DNA构型;DNA定量分析提示C基因截短型HBV的包装效率较野生型HBV提高3~40倍。结论 C基因截短型HBV变异体为复制缺损型,单独转染后不能在肝细胞内包装与复制,但在缺失包装信号ε的相应辅助病毒辅助下可有效复制并包装成子代病毒颗粒分泌到胞外,且包装效率大大提高。  相似文献   
89.
目的 通过食道心房起搏负荷试验 ,使用彩色多普勒超声心动图对左心室室壁运动状态及左心室舒缩功能改变进行评价 ,以提高冠心病诊断的检出率 ;方法 使用心脏程序刺激仪经食道起搏导管调整心率达次极量 ;同时使用彩色多普勒超声心动仪进行左心室室壁运动记分并记录二尖瓣口及主动脉瓣环部血流频谱 ;结果 经食道心房起搏增加心脏负荷 ,应用左心室每搏量 (SV)、主动脉瓣环部流速积分 (VTIAO)、等容舒张时间 (IVRT)、二尖瓣口流速积分(VTIMV) )、快速充盈分数 (RFI)及室壁运动记分指数 (WMSI)作为指标在冠心病诊断中可提高检出率 ,以WMSI结合其它两项左心室舒缩功能阳性指标 ,其冠心病诊断的检出率为 95 % ,假阳性率为 3% ;结论 经食道心房起搏彩色多普勒负荷超声心动图 (TPDE)在冠心病诊断中有较高的应用价值 ,因其简便、实用和安全 ,宜在临床广泛推广使用  相似文献   
90.
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