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91.
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The color complementation assay (CCA) is a method of allele-specific DNA amplification by which competitive priming and extension of fluorescently labeled oligonucleotide primers determine the color of DNA amplification product. This diagnostic method precludes the need for radioisotopes, electrophoresis, and multiple high-stringency reaction conditions. The multiplicity of mutant globin genes present in Southeast Asians complicates clinical diagnosis and underscores the importance of DNA-based diagnostic methods. We have applied CCA to distinguish beta A and beta E alleles. Competing 15mer primers were a fluorescein-labeled complement to beta A and a rhodamine-labeled complement to beta E, identical except for their central nucleotides. A common unlabeled primer was used to amplify DNA product, the color of which was determined by the perfectly complementary primer. Color photography and spectrofluorometry, as well as a method of black-white photography that we developed to distinguish fluorescein- and rhodamine- labeled DNA, were used to record results. We applied CCA to define the complex genotype of a Thai woman with thalassemia intermedia, 96% HbE, and 4% HbF whose possible genotypes included several permutations of alpha-thalassemia, beta-thalassemia, and beta E genes. zeta-Globin gene mapping of DNA doubly digested with Bg/II and Asp 718 showed the -alpha 3.7/--SEA genotype, and CCA confirmed homozygous beta E/beta E. The CCA is useful for diagnosing the compound hemoglobin genotypes of Southeast Asians and could be applied also to prenatal diagnosis in this population. 相似文献
93.
Diagnostic role of an immunoassay-detected polymorphism of factor IX for potential carriers of hemophilia B 总被引:3,自引:1,他引:3
In hemophilia B, assays based on a monoclonal antifactor IX specific for the Thr-148 variant of an exonic polymorphism have diagnosed carriers in selected families by either establishing linkage or by indicating the presence or absence of a given normal factor IX. The sensitivity of the immunoassays for detecting heterozygous women was explored by comparing results from immunoassays with solid-phase polyclonal v the monoclonal antifactor IXs. Factor IX with the normal Ala-148 variant gave a flat dilution curve, qualitatively distinct from factor IX with the Thr-148 variant in the monoclonal assay. The two were indistinguishable in the polyclonal assay. Mixtures of equal amounts of the two types gave an intermediate result, about half as reactive in the monoclonal as compared with the polyclonal assay system. Whereas mixtures with 10% Ala-148 and 90% Thr-148 factor IXs could not readily be distinguished from Thr-148 factor IX plasma, as little as 1% of the Thr-148 protein was detected in Ala-148 factor IX plasma. The frequency of the Ala-148 variant varied in individuals with different ethnic backgrounds; it was found in 29% of white, 12% of black, and none of Asian blood donors' factor IX genes in Seattle. Only 4% of samples from South African black men were nonreactive (ie, Ala- 148). The Thr/Ala-148 dimorphism is in strong linkage disequilibrium with Taql restriction fragment length polymorphisms (RFLPs). Three recombinations were noted in normal white genes and one in a normal black factor IX gene (less than 2% of those examined). In 34 white families with at least one woman being a possible carrier, genetically, the immunoassay results were informative in 18. RFLP analyses were informative in eight of the 15 families tested. In five families each, assignment of carrier status was made to a woman by only DNA or only immunoassay results, whereas the other approach was noninformative. The immunoassays provide a rapid, inexpensive screening test and complement DNA analysis in white women who are potential carriers of hemophilia B. 相似文献
94.
Histomorphological analysis shows at least two different patterns in patients with ankylosing spondylitis. Bone marrow edema, lymphocytic infiltrates, increased osteoclast density and increased microvessel density are typical findings in acute inflammation. In areas of new bone formation newly formed trabecular bone shows formation of fibrous tissue in the bone marrow with new cartilage formation and persistently high microvessel density. Morphological changes reminiscent of endochondral ossification can also be observed. Compared to peripheral joints, such as the knee, synovitis is not a predominant finding in the spine, the sacroiliac joints and the hip. Enthesitis is characterised by lymphocytic infiltrates around fibrous cartilage followed by subsequent ankylosis. The molecular mechanisms which promote the transition from inflammation to new bone formation in patients with ankylosing spondylitis are not well understood. 相似文献
95.
96.
Thomas E. Smith Anita Appel Sheila A. Donahue Susan M. Essock Doreen Thomann-Howe Adam Karpati Trish Marsik Robert W. Myers Mark J. Sorbero Bradley D. Stein 《Administration and policy in mental health》2014,41(5):588-597
This study examined whether Medicaid claims and other administrative data could identify high-need individuals with serious mental illness in need of outreach in a large urban setting. A claims-based notification algorithm identified individuals belonging to high-need cohorts who may not be receiving needed services. Reviewers contacted providers who previously served the individuals to confirm whether they were in need of outreach. Over 10,000 individuals set a notification flag over 12-months. Disengagement was confirmed in 55 % of completed reviews, but outreach was initiated for only 30 %. Disengagement and outreach status varied by high-need cohort. 相似文献
97.
Lisa Lynn ten Bergen Aleksandra Petrovic Anders Krogh Aarebrot Silke Appel 《Scandinavian journal of immunology》2020,92(4):e12945
In the past decades, clinical and experimental evidence has demonstrated that psoriasis is an immune-mediated inflammatory disease of the skin that occurs in genetically susceptible individuals. Psoriasis also shows clear autoimmune pathomechanisms, but specific cellular targets for the onset and maintenance of psoriatic lesions were not established until 2014. Since then, four psoriasis autoantigens were discovered, namely cathelicidin LL-37, melanocytic ADAMTSL5, lipid antigen PLA2G4D and keratin 17. Autoreactive T cells against these autoantigens were found in a number of patients with moderate-to-severe plaque psoriasis. Moreover, the discovery of autoantibodies against LL-37 and ADAMTSL5 and their strong association with psoriatic arthritis (PsA) suggest a potential role of these autoantibodies in the pathogenesis of PsA. This review discusses the current studies on psoriatic autoantigens and the associated circulating autoantibodies and their mechanisms involved in the development and maintenance of psoriatic plaques. Recent autoimmune evidence fuelled the discussion on psoriasis as an autoimmune skin disorder and has the potential to develop new treatment strategies with protective and therapeutic antigen-targeted methods. 相似文献
98.
Long-term follow-up of patients with lupus nephritis. A study based on the classification of the World Health Organization 总被引:9,自引:0,他引:9
G B Appel D J Cohen C L Pirani J I Meltzer D Estes 《The American journal of medicine》1987,83(5):877-885
The long-term course of 56 patients with systemic lupus erythematosus who had precisely defined renal histology and carefully assessed clinical status at the time of their initial renal biopsy prior to 1976 was evaluated and analyzed by life-table analysis. The average length of follow-up has now been greater than 10 years since initial biopsy. Patients with mesangial lesions (World Health Organization [WHO] classes IIA and IIB) had a more favorable renal and patient survival at five and 10 years than did patients in the other WHO classes (III, IV, and V). Individual renal histologic features of activity and chronicity when combined into an activity index and a chronicity index did not significantly predict renal survival in this population, nor did the presence of hypertension or renal dysfunction at the time of the initial renal biopsy significantly influence renal or patient survival. Patients with the nephrotic syndrome at initial biopsy had a poorer renal survival than did patients without the nephrotic syndrome. However, patients who experienced a remission of the nephrotic syndrome fared better in terms of both renal and patient survival than did those patients without a remission. By life-table analysis, patient survival was significantly better for patients in whom biopsy was performed after 1973 than for those in whom biopsy was performed prior to that time despite similar clinical features and WHO histology in each group interval. Our data suggest that improved survival for patients in recent studies may relate to better supportive care and more selective use of immunosuppressive therapy in patients with milder forms of lupus nephritis. 相似文献
99.
胰腺癌组织VEGF和MVD表达与CT灌注成像的关系 总被引:1,自引:0,他引:1
血管内皮生长因子作为肿瘤血管生成的一种主要调控因子,与微血管密度密切相关.胰腺癌组织的血管内皮生长因子和微血管密度的测定对于判断患者的预后,指导临床治疗和判断疗效等具有重要作用.CT灌注成像可以通过无创伤检查反映胰腺癌的肿瘤血管构成, 在治疗前后提供有价值依据,对胰腺癌的诊治有重要意义. 相似文献
100.