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11.
目的 采用聚合酶链式反应(PCR)技术和胶体金技术建立一种呼吸道真菌感染核酸胶体金试纸条检测方法,并对其检测效果进行评价。 方法 根据GenBank数据库选择真菌内转录间隔区(ITS)基因片段作为靶基因,应用DNAMAN软件对真菌ITS基因片段进行分析,并分别在真菌通用引物5'端用生物素(Biotin)和异硫氰酸荧光素(FITC)进行修饰标记;建立PCR体系,进行体系的最佳条件优化;确定胶体金免疫层析试纸条标记链霉亲和素的最佳标记量和质控线及检测线最佳包被物浓度,组装核酸胶体金试纸条,对试纸条的特异度、灵敏度、重复性和稳定性进行验证。 结果 水煮法提取白假丝酵母菌、新生隐球菌和毛霉菌DNA,浓度为180 μg·L-1以上,纯度为1.60~2.10;在pH 7.0条件下,每100 μL胶体金溶液中制备胶体金标记链霉亲和素最佳标记量为 3.3 μg,质控线包被Biotin化牛血清白蛋白(BSA-Biotin)浓度为2.00 g·L-1,检测线包被抗FITC抗体浓度为1.00 g·L-1。核酸试纸条的特异度与电泳结果一致,仅白假丝酵母菌、新生隐球菌和毛霉菌出现阳性结果,与金黄色葡萄球菌、肺炎链球菌、乙型溶血性链球菌、铜绿假单胞菌、肺炎克雷伯菌、鲍曼不动杆菌和大肠埃希菌等常见呼吸道感染细菌无交叉反应。灵敏度检测,白假丝酵母菌、新生隐球菌和毛霉菌的DNA浓度分别为10-4、10-2和10-3 mg·L-1时核酸试纸条仍可准确检出,而普通PCR电泳结果显示白假丝酵母菌、新生隐球菌和毛霉菌最低检测浓度分别为0.01、1.00和0.10 mg·L-1;重复性检测,在不同实验室不同操作人员对核酸试纸条进行验证,结果一致,重复性良好;稳定性检测,核酸试纸条在第6、9和12个月进行检测,结果符合预期,稳定性良好。 结论 本研究建立的呼吸道真菌感染核酸胶体金试纸条可以检测白假丝酵母菌、新生隐球菌和毛霉菌等真菌,特异度和灵敏度均较高,操作简便且快速。 相似文献
12.
Cells with dendritic morphology and bright interleukin-1 alpha staining circulate in the blood of patients with rheumatoid arthritis. 总被引:1,自引:1,他引:1
Freshly isolated peripheral blood mononuclear cells (PBMC) from 10 healthy volunteers, 28 patients with rheumatoid arthritis (RA), eight patients with osteoarthritis, and five patients with ankylosing spondylitis were examined for interleukin-1 alpha (IL-1 alpha) and interleukin-1 beta (IL-1 beta) production using monoclonal antibodies and an indirect immunofluorescent method. In freshly isolated PBMC from healthy controls very few cells were stained for either IL-1 type. All 20 RA patients who were not receiving parenteral gold therapy had PBMC staining for IL-1 alpha. In these patients, up to 7.5% of PBMC showed bright IL-1 alpha staining (range 1.2-7.5%). No IL-1 beta staining was seen. These IL-1 alpha-staining cells had a dendritic morphology and the percentage of cells staining correlated well with levels of C-reactive protein, an index of disease activity in these RA patients. Significantly fewer IL-1 alpha-staining cells were present in the peripheral blood of RA patients receiving gold therapy and in the blood of patients with osteoarthritis and ankylosing spondylitis. These IL-1 alpha-containing cells, circulating in the blood of RA patients and correlating with disease activity have not been previously described. These results support the idea that IL-1 alpha plays an important role in the pathogenesis of rheumatoid inflammation. 相似文献
13.
A recurrent cardiac myxoma is examined histochemical ly at the ultrastructural level. By routine electron microscopy the stellate “myxoma” cell exhibits features suggestive of a secretory function in synthesis of its myxoid stroma. Spicer's high iron diamine (HID), which stains specifically for sulfated glycoconjugates, is utilized for intracellular localization of glycosaminoglycans. HID-positive reactive sites are localized within the Golgi-derived vacuoles and secretory granules of the myxoma cells. No staining is obtained with other cytoplasmic organelles except rare secondary lyso-somes. Although colloidal iron is less specific, both intracellular and extracellular positive reactive sites are observed. With ruthenium red staining the proteoglycans in the extracellular stroma can be visualized as numerous positively stained, polygonal 250-500 A matrix granules with faint filamentous projections. Positive intracellular ruthenium red-stained granules are also observed within the Golgi-derived vacuoles. The alcianophilia of the myxoid stroma with Alcian blue is almost completely abolished by prior treatment with bovine testicular hyaluronidase but is unaffected by leech hyaluronidase, indicating chondroitin sulfates A and/or C, not hyaluronic acid, as the major biochemical constituents of the stroma and the observed extracellular matrix granules. The above findings provide cytochemical evidence of intracellular synthesis of sulfated glycosaminoglycans and proteoglycans of the myxoma cell and its active participation in production of its stroma. 相似文献
14.
目的:利用蒙特卡罗程序Geant4模拟13.5 MeV和6 MeV X射线照射细胞内的纳米颗粒,分析其光核反应的剂量贡献份额。方法:以纳米金颗粒(GNP)为例,分别模拟6 MeV和13.5 MeV照射细胞内的GNP,给出各自条件下由GNP造成的剂量贡献。创建水模体(0.426 mm×0.426 mm×0.426 mm),包含1 103个细胞,作为GNP的载体。在6 MeV和13.5 MeV下分别模拟细胞中包含和不包含GNP所造成的剂量沉积。结果:13.5 MeV X射线照射,其由GNP造成的剂量贡献为5.12 cGy,细胞总能量沉积为25.37 cGy,由GNP引起的剂量贡献占20.19%;6 MeV X射线照射,其由GNP造成的剂量贡献为2.87 cGy,细胞总能量沉积为23.05 cGy,由GNP造成剂量贡献约为12.46%。与6 MeV相比,13.5 MeV下由GNP光核反应造成的剂量贡献占7.7%。结论:对于细胞模型内纳米金的研究表明,GNP确实能引起额外的剂量贡献。由于GNP光核反应引起的剂量贡献很低,难以作为能够被原位激活的放射源使用。 相似文献
15.
吗啡和甲基安非他明单克隆抗体联合胶体金检测试卡的研制 总被引:1,自引:0,他引:1
目的:研制吗啡-甲基安非他明单克隆一步法毒品二合一胶体金检测试卡,用于毒品的检测和可疑人群的筛查。方法:应用杂交瘤技术制备抗吗啡-甲基安非他明的单克隆抗体(McAb);ELISA方法检测McAb效价;免疫胶体金技术制备二合一胶体金检测试卡。结果:①ELISA法检测McAb的效价:抗吗啡McAb的效价为1∶3.2×103,抗甲基安非他明McAb的效价为1∶1.6×103。②检测试卡的灵敏度:检测尿中吗啡的最低浓度为300ng/ml,甲基安非他明的最低浓度为1000ng/ml;③检测试卡的特异性:7天以上未吸毒者饮用可口可乐、口服感冒药及吸烟等其尿中未检出阳性反应。④与Pan Probe Biotech公司的单一检测吗啡和甲基安非他明试纸灵敏度对比实验显示出吸毒后4~5天的尿样仍呈阳性反应。结论:由于具有高度敏感性和特异性,以及快速、直观等优势,本试卡在毒品滥用筛查工作中有重要的定性判别意义。 相似文献
16.
Differentiating Small Round Cell Sarcomas of the Soft Parts by an Innovative Immunogold Labeling Method: An Ultrastructural Study 总被引:1,自引:0,他引:1
A new immunoelectron microscopy procedure was developed by remaking the fixed-frozen tissue specimens into LR White resin blocks suitable for postembedding colloidal gold immunolabeling, and used to examine 16 cases of small round cell soft tissue sarcomas. In rhabdomyosarcoma, ultrastructural double-immunogold staining demonstrated a coexpression of muscle specific actin and desmin in the same tumor cell. In both Ewing's sarcoma and peripheral neuroepithelioma, the heterogeneous expression of MIC2 gene product (p30/32MIC2) in each tumor cell was demonstrated as well. In peripheral neuroepithelioma, the colloidal gold immunolabeling for neurofilament demonstrated the intermediate filaments surrounding microtubules. The procedure for ultrastructural colloidal gold immunolabeling using fixed-frozen tissue is thus considered to be useful not only for tumor diagnosis, but also for investigating various subcellular structures. 相似文献
17.
Tokuhiro Ishihara Yoshimi Yamashita Yoshiko Okuzono Tadaaki Yokota Mutsuo Takahashi Toshiaki Kamei Fumiya Uchino Noboru Matsumoto Shiro Miwa Hisaichi Fuji Takeshi Kozaki 《Ultrastructural pathology》1985,8(1):13-23
By light and electron microscopy, we observed foamy cells in the spleens from a patient with hemolytic anemia due to red cell adenosine deaminase (ADA) overproduction, a patient with rheumatoid arthritis (RA) treated with gold, and patients with idiopathic thrombocytopenic purpura (ITP)
The foamy cells associated with red cell ADA overproduction were essentially similar to Gaucher-like cells described in patients with thalassemia, and it was suggested that the accelerated destruction of red cells was one of the factors responsible for the development of foamy cells. Foamy cells in ITP and RA were closely associated with an increased destruction of platelets in the spleen. Morphologic transitions between phagocytosed platelets and myelinlike materials were traced in these disorders. In RA, however, foamy cells were heterogeneous from an ultrastructural standpoint, with different cytoplasmic inclusions. In addition to myelinlike materials, dense bodies, vacuoles with flocculent materials, and gold were noted in most of foamy cells. As gold compounds are known to inhibit lysosomal enzymes, we surmise that an acquired disturbance in lysosomal digestion is partially responsible for the accumulation of intermediate metabolites.
In the pathogenesis of foamy cells associated with blood cell dyscrasia, the accelerated destruction of blood cells and/or acquired disorders in catabolic pathways within the macrophages are suggested to be the underlying mechanism of an intralysosomal accumulation of incompletely degraded cellular debris. 相似文献
The foamy cells associated with red cell ADA overproduction were essentially similar to Gaucher-like cells described in patients with thalassemia, and it was suggested that the accelerated destruction of red cells was one of the factors responsible for the development of foamy cells. Foamy cells in ITP and RA were closely associated with an increased destruction of platelets in the spleen. Morphologic transitions between phagocytosed platelets and myelinlike materials were traced in these disorders. In RA, however, foamy cells were heterogeneous from an ultrastructural standpoint, with different cytoplasmic inclusions. In addition to myelinlike materials, dense bodies, vacuoles with flocculent materials, and gold were noted in most of foamy cells. As gold compounds are known to inhibit lysosomal enzymes, we surmise that an acquired disturbance in lysosomal digestion is partially responsible for the accumulation of intermediate metabolites.
In the pathogenesis of foamy cells associated with blood cell dyscrasia, the accelerated destruction of blood cells and/or acquired disorders in catabolic pathways within the macrophages are suggested to be the underlying mechanism of an intralysosomal accumulation of incompletely degraded cellular debris. 相似文献
18.
A. E. Smits-van Prooije Chr. Vermeij-Keers R. E. Poelmann M. M. T. Mentink J. A. Dubbeldam 《Anatomy and embryology》1988,177(3):245-256
Summary The formation of mesectodermal cells by the neural crest in 5- to 41-somite stage embryos was investigated experimentally in rat embryos cultured in vitro, using lectincoated colloidal gold as a probe. This method labelled all ectodermal cells, among them neural crest, surface ectodermal placodal and epiblastic (primitive streak) cells. The neural crest provides the mesodermal compartment of the entire head region with cells, including the primitive cranial ganglia and the branchial arches. In the head region migration of neural crest cells over a great distance (long-distance migration) was not observed. In the trunk region neural crest derived cells were mainly found to form the primitive spinal ganglia and the sympathetic trunk, once again without long-distance cell migration. Structures and tissues that supposedly were derived from the primitive streak were hardly labelled with colloidal gold. Surface ectodermal placodes were not only found at the expected sites (e.g. epibranchial placodes) but also in the ectoderm covering the transverse septum and lateral abdominal walls. 相似文献
19.
Yutaka Inoue Yukari Kitani Satoshi Osakabe Yukitoshi Yamamoto Isamu Murata Ikuo Kanamoto 《Nutrients》2021,13(6)
The purpose of this study was to examine how gold kiwifruit pericarp (pericarp is defined as the skin of the fruit) consumption and the timing thereof affect the postprandial blood glucose profile. The study was conducted on twelve healthy volunteers (six men and six women). According to our results, the simultaneous intake of gold kiwifruit with bread and the prior intake of gold kiwifruit evidently suppressed the postprandial blood glucose elevation compared with exclusive bread intake. There was no significant difference in postprandial blood glucose changes between the ingestion of gold kiwifruit pericarp and pulp and that of gold kiwifruit pulp only. The highest postprandial blood glucose elevation was suppressed by 27.6% and the area under the blood glucose elevation curve by 29.3%, even with the exclusive ingestion of gold kiwifruit pulp. We predicted that the ingestion of both the pericarp and pulp of gold kiwifruit would reduce the postprandial blood glucose elevation to a greater extent than that of gold kiwifruit pulp only; however, there was no significant difference between the two. These results indicate that gold kiwifruit consumption significantly suppresses the postprandial blood glucose elevation regardless of pericarp presence or absence and the timing of ingestion. 相似文献
20.
目的:用胶束增溶分光光度法测定水中镉的含量,并比较了乳化剂OP(聚乙二醇辛基苯基醚)和吐温-20(聚氧乙烯山梨醇酐单月桂酸酯)的胶束增溶作用。方法:分别以体积分数为10%OP和体积分数为10%吐温-20为增溶剂,以PAN(1-(2-吡啶偶氮)-2-萘酚)为显色剂,在555nm波长处测定水中镉络合物的吸光度。结果:相同条件下,同浓度的镉络合物用OP的吸光度值是吐温-20的1.6倍,用OP作乳化剂平均回收率为96.5%,平行样品的相对平均偏差为2.57%,标准曲线线性良好,回归系数r=0.999 9,ε=4.6×104L·mol-1·cm-1。结论:乳化剂OP的增溶作用优于吐温-20,此法测定水中痕量镉较好。 相似文献