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排序方式: 共有2213条查询结果,搜索用时 31 毫秒
101.
目的 探讨受体酪氨酸激酶肝配蛋白A型受体2(EphA2)对屋尘螨提取物(HDM)诱导气道上皮细胞表达炎症细胞因子的作用及其机制.方法 用EphA2小干扰RNA(siRNA)转染气道上皮细胞株16HBE细胞建立EphA2敲减的细胞模型,HDM刺激16HBE细胞后,采用实时定量PCR检测EphA2、白细胞介素6(IL-6)... 相似文献
102.
目的 探索木尘对肺组织损伤的机制.方法 以0、100、400、800 mg/kg木尘和博来霉素阳性对照通过气管内注入的方式对大鼠进行染尘,于染毒后7、15、30、60 d测定肺组织匀浆的内皮素-1、丙二醛、羟脯氨酸和胶原蛋白的含量.结果 实验期间木尘染尘组大鼠羟脯氨酸和胶原蛋白升高不明显,第7天内皮素-1、丙二醛水平与对照组相比显著升高,并呈剂量-反应关系,第15天后与对照组相比差异不显著.结论 肺染木尘可引起肺组织内脂质过氧化作用增强,造成结缔组织和上皮、内皮细胞的损伤,但不刺激肺成纤维细胞合成胶原蛋白,致肺纤维化作用不明显. 相似文献
103.
Akira Igarashi Yasuhiro Ebihara Tomoaki Kumagai Hiroyuki Hirai Kinya Nagata Kohichiro Tsuji 《Allergology international》2018,67(2):234-242
Background
Several methods have been developed to detect allergen-specific IgE in sera. The passive IgE sensitization assay using human IgE receptor-expressing rat cell line RBL-2H3 is a powerful tool to detect biologically active allergen-specific IgE in serum samples. However, one disadvantage is that RBL-2H3 cells are vulnerable to high concentrations of human sera. Only a few human cultured cell lines are easily applicable to the passive IgE sensitization assay. However, the use of human induced pluripotent stem cells (iPSCs) to generate human mast cells (MCs) has not yet been reported.Methods
The nuclear factor-kappa B (NF-κB)-responsive luciferase reporter gene was stably introduced into a human iPSC line 201B7, and the transfectants were induced to differentiate into MCs (iPSC-MCs). The iPSC-MCs were sensitized overnight with sera from subjects who were allergic to cedar pollen, ragweed pollen, mites, or house dust, and then stimulated with an extract of corresponding allergens. Activation of iPSC-MCs was evaluated by β-hexosaminidase release, histamine release, or luciferase intensity.Results
iPSCs-MCs stably expressed high-affinity IgE receptor and functionally responded to various allergens when sensitized with human sera from relevant allergic subjects. This passive IgE sensitization system, which we termed the induced mast cell activation test (iMAT), worked well even with undiluted human sera.Conclusions
iMAT may serve as a novel determining system for IgE/allergens in the clinical and research settings. 相似文献104.
Hong-Ren Yu Jui-Hsiu Tsai Chun-Hung Richard Lin Jiu-Yao Wang Yen-Hsia Wen Shihn-Sheng Wu Yuan Hou Ing-Kit Lee Hung-Pin Tu Yi-Chen Lee 《Allergology international》2019,68(4):486-493
BackgroundDengue fever (DF) is the most rapidly spreading mosquito-borne viral disease. Practical vaccines or specific therapeutics are still expected. Environmental factors and genetic factors affect the susceptibility of Dengue virus (DV) infection. Asthma is a common allergic disease, with house dust mites (HDMs) being the most important allergens. Asthmatic patients are susceptible to several microorganism infections.MethodsA nationwide population-based cohort analysis was designed to assess whether to determine whether asthma can be a risk factor for DF.ResultsUnexpectedly, our data from a nationwide population-based cohort revealed asthmatic patients are at a decreased risk of DF. Compared to patients without asthma, the hazard ratio (HR) for DF in patients with asthma was 0.166 (95% CI: 0.118–0.233) after adjustment for possible confounding factors. In the age stratification, the adjusted HR for DF in young adult patients with asthma was 0.063. Dendritic cell-specific intercellular adhesion molecule 3-grabbing non-integrin (DC-SIGN) of dendritic cells (DCs) is an important entry for DV. Through another in vitro experiment, we found that HDM can diminish surface expression of DC-SIGN in monocyte-derived DCs and further decrease the cellular entry of DV.ConclusionsDecreased DC-SIGN expression in DCs of allergic asthmatic patient may be one of many factors for them to be protected against DF. This could implicate the potential for DC-SIGN modulation as a candidate target for designing therapeutic strategies for DF. 相似文献
105.
Ulrike Maria Dauter Ayman Alhamdow Andrea Cediel-Ulloa Anda Roxana Gliga Maria Albin Karin Broberg 《Scandinavian journal of work, environment & health》2022,48(1):21
ObjectiveThis study tested for an association between early cancer-related biomarkers and low-to-moderate exposure to fumes from welding mild steel.MethodsMale, non-smoking participants from southern Sweden were recruited and examined (N=338, 171 welders and 167 controls); of these, 78 welders and 96 controls were examined on two occasions six years apart. Exposure to welding fumes was evaluated by measuring respirable dust, welding years, and cumulative exposure. DNA methylation of CpG sites within the cancer-related genes AHRR, F2RL3, and B3GNTL1 was measured by pyrosequencing and relative mitochondrial DNA copy number and telomere length were measured by qPCR in whole-blood samples. Multivariate models were used for longitudinal analysis.ResultsMedian exposure to respirable dust was 0.7 mg/m3 at both timepoints, adjusted for use of personal protective equipment. Compared with controls, welders showed a significant decrease over time in DNA methylation of B3GNTL1 CpG1 and CpG4 [adjusted for age, body mass index, and smoking: β=-0.66, standard error (SE)=0.28; β=-0.48, SE=0.24, respectively]. In addition, exposure to respirable dust and cumulative exposure was associated with a decrease in methylation of F2RL3 CpG2 among all welders (adjusted β=-0.67, SE=0.23 and β=-0.03, SE=0.02, respectively). No significant associations were found for AHRR, mitochondrial DNA copy number, or telomere length.ConclusionLow-to-moderate exposure to welding fumes was associated with a small effect on selected early epigenetic biomarkers of cancer. The direction of the methylation pattern (lower methylation of specific CpG sites) indicates early lung cancer-related changes associated with mild steel welding. 相似文献
106.
Dimitrios KOUTSOUMPLIAS Artemis DAMATI Efthymios THANASIAS Dimitris VLASTOS George HALKOS Demetrios MATTHOPOULOS Vasilios MAKROPOULOS 《Industrial health》2022,60(1):47
Shipyards are industrial areas where workers are likely exposed to environmental pollutants such as welding fumes, fine organic solvent and dye dust, that render the occupational environment a high risk one. Assessing the risk that workers are exposed to is a high critical factor in improving their working conditions. The present study aims to investigate the potential genetic damage to workers exposed to a harsh environment in a Greek shipyard. It is focused on assessing the percentage of induced micronuclei, as well as on changes in the various cell types of shipyard workers’ oral mucosa epithelium by implementing the buccal micronucleus cytome assay. Exposed workers appeared with statistically significant induced micronuclei as compared to office employees. Statistically, significant cell lesions were detected and are related to workers’ exposure to environmental conditions. The workers’ smoking habit contributed as well to the observed buccal epithelial cell alterations. The observed data signify the high-risk workers are exposed; resulting in the shipyard’s management the need to implement measures improving the working environment conditions and to reevaluate the workers’ personal protective equipment requirements. 相似文献
107.
目的 研究尘螨肠道微生物蛋白Hypothetical protein CE2118的表达和纯化,为研究其在尘螨疫苗免疫治疗中的作用奠定基础。方法 采用生物信息学方法,根据GenBank中Hypothetical protein CE2118蛋白的基因序列,将其中稀有密码子改造为大肠杆菌常用密码子并进行二级结构优化,合成Hypothetical protein CE2118基因,构建原核表达载体pGEX 6P-1-hypothetical protein CE2118并经酶切鉴定,在大肠埃希菌Rosetta(DE3)中用异丙基-β-D-硫代半乳糖苷(IPTG)诱导表达,重组产物采用GST亲和层析纯化柱纯化。结果 经密码子改造和二级结构优化后Hypothetical protein CE2118基因长度为588bp,其编码蛋白理论分子量为21 kDa。重组表达载体经酶切鉴定与理论推测结果相符,该基因经IPTG诱导在大肠埃希菌Rosetta(DE3)中得到高效的可溶性表达,纯化后的重组蛋白分子量约为21 kDa,其单一蛋白纯度达95%以上。结论 本研究成功构建了Hypothetical protein CE2118基因的pGEX6P-1原核重组质粒,获得的可溶性重组蛋白为进一步研究肠道微生物蛋白Hypothetical protein CE2118在尘螨疫苗免疫治中的作用机理奠定基础。 相似文献
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