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61.
T-gamma lymphoproliferative disease (T-gamma LPD) is a chronic disorder of mature T cells that is associated with neutropenia and autoimmune phenomena. Although the progression of the lymphoproliferation is indolent, it is often associated with a monoclonal proliferation of T- cell-type large granular lymphocytes (LGL) that manifest multiple in vitro suppressor and cytotoxic activities. We considered the possibility that the granulocytopenia or anemia might represent an autoimmune disorder mediated by the monoclonal LGL via T-cell receptor (TCR) recognition of an antigen involved in hematopoiesis. Therefore, in an effort to characterize the usage of the TCR alpha- and beta-chain genes in patients with T-gamma LPD, we cloned and sequenced TCR alpha- and beta-chain mRNAs derived from the T-cell type LGL of five patients. The five patients studied did not use a common V alpha nor a common J alpha segment. However, an unusual finding was observed in one of the patients where the occurrence of a single variable-diversity-junctional (VDJ) rearrangement of the beta chain confirmed the monoclonal origin of the LGL proliferation. In accord with this evidence for monoclonality, many of the cells studied used a common V alpha (V alpha 19.1). In contrast to this common V alpha usage, there was a marked diversity of the J alpha segments and N-region addition that were associated with the V alpha 19.1 segment. This pattern of common V alpha usage associated with different N and J alpha segments suggests an immune-mediated selection process affecting the TCR alpha chain occurring after the transformation event that established the clone. We suggest that the T-cell-type LGL malignant clone might have developed autoreactivity conferred by the selected TCR alpha chain and that this autoreactivity might be implicated in this patient's anemia. 相似文献
62.
既往研究提示白细胞介素4(IL-4)、白细胞介素4受体(IL-4RA)基因与血清总IgE水平、过敏性疾病有关。然而结论并不一致。我们的研究目的在于调查华人、马来人及印度人中IL-4、IL-4RA的3个基因位点的基因型(C590T、Ile50Val、Q576R)与血清总IgE水平是否存在相关性。 相似文献
63.
Human myeloperoxidase gene expression in acute leukemia 总被引:2,自引:0,他引:2
64.
We evaluated the hematologic, rheologic, and biochemical features of erythrocytes obtained from 10 relatives of a 5-yr-old black female with hereditary pyropoikilocytosis (HPP) and severe hemolytic anemia. Erythrocyte morphology was normal in the father and five other relatives, but ghost mechanical fragility and drug-induced red cell endocytosis were increased, as was the percentage of spectrin dimers noted on 3.2% nondenaturing PAGE of spectrin extracts. Identical changes were also noted in the mother and her sister, whose erythrocytes were elliptocytic and exhibited morphological changes upon heating to 45 degrees-48 degrees C (normal 49 degrees). The two other family members were normal in every respect. SDS-PAGE analysis of membrane proteins demonstrated diminished amounts of spectrin in HPP erythrocytes, but was normal in other family members. A diffuse band (mol wt 575,000-665,000), composed entirely of spectrin, was apparent adjacent to the dimer region on nondenaturing PAGE of spectrin extracts from the propositus, mother, and aunt. In this family, HPP appears to have resulted from compound heterozygosity for two distinct genetic abnormalities (reflected by the differences between elliptocytic and nonelliptocytic carriers). Although the membrane abnormalities in carriers did not result in hemolytic anemia, they were of sufficient magnitude to allow the detection of the carrier state. 相似文献
65.
Analysis of human platelet glycoproteins IIb-IIIa and Glanzmann's thrombasthenia in whole blood by flow cytometry 总被引:4,自引:0,他引:4
Antibodies that bind to human platelet membrane glycoproteins IIb and IIIa were used to develop methods for analyzing platelet membrane components by flow cytometry. Platelets were tentatively identified by their low-intensity light scatter profiles in whole blood or platelet- rich plasma preparations. Identification of this cell population as platelets was verified by using platelet-specific antibodies and fluorescein-conjugated antiimmunoglobulin. Two-parameter analysis of light scatter versus fluorescence intensity identified greater than 98% of the cells in the "platelet" light scatter profile as platelets due to their acquired fluorescence. Both platelet-rich plasma and whole blood were used to study platelet membrane glycoproteins IIb and IIIa on a single cell basis in an unwashed system. Prostacycline was included in these preparations as a precautionary step to inhibit platelet aggregation during analysis. Flow cytometry is a successful technique for rapid detection of platelet membrane defects such as Glanzmann's thrombasthenia. Platelets from Glanzmann's thrombasthenic individuals were readily distinguished from platelets with normal levels of glycoprotein IIb and IIIa and from platelets with glycoprotein levels characteristic of heterozygote carriers of this disorder. This technique provides a sensitive tool for investigating platelet functional defects due to altered expression or deficiency of platelet surface proteins. 相似文献
66.
Programmed cell death, also known as apoptosis, is frequently initiated when cells are deprived of specific trophic factors. To investigate if accelerated apoptosis contributes to the pathogenesis of Diamond- Blackfan anemia (DBA), a rare pure red blood cell aplasia of childhood, we studied the effect of erythropoietin (epo) deprivation on erythroid progenitors and precursors from the bone marrow of DBA patients as compared with hematologically normal controls. Apoptosis in response to epo deprivation was evaluated by enumeration of colony-forming unit- erythroid (CFU-E)- and burst-forming unit-erythroid (BFU-E)-derived colonies in plasma clot semisolid culture and by the identification of typical DNA oligosomes by gel electrophoresis from marrow mononuclear cells in liquid culture. In all DBA patients there was a marked decrease in CFU-E- and BFU-E-derived colony formation compared with normal controls at comparable time points of epo deprivation, with a complete loss of CFU-E-derived colonies in semisolid culture by 9 hours of epo deprivation versus 48 hours in controls. The BFU-E-derived colony response to epo deprivation displayed a similar pattern of decrement. Apoptotic changes assessed by the presence of characteristic DNA fragmentation began in the absence of epo deprivation and were readily detected within 3 hours of epo deprivation in DBA cultures versus 9 hours in controls. We conclude that DBA is characterized by accelerated apoptosis as measured by the loss of erythroid progenitor clonogenicity and increased progenitor and precursor DNA fragmentation leading to the formation of characteristic oligosomes, consistent with an intrinsic erythroid-progenitor defect in which increased sensitivity to epo deprivation results in erythroid failure. 相似文献
67.
Mark A Currier Francis K Eshun Allyson Sholl Artur Chernoguz Kelly Crawford Senad Divanovic Louis Boon William F Goins Jason S Frischer Margaret H Collins Jennifer L Leddon William H Baird Amy Haseley Keri A Streby Pin-Yi Wang Brett W Hendrickson Rolf A Brekken Balveen Kaur Timothy P Cripe 《Molecular therapy》2013,21(5):1014-1023
Understanding the host response to oncolytic viruses is important to maximize their antitumor efficacy. Despite robust cytotoxicity and high virus production of an oncolytic herpes simplex virus (oHSV) in cultured human sarcoma cells, intratumoral (ITu) virus injection resulted in only mild antitumor effects in some xenograft models, prompting us to characterize the host inflammatory response. Virotherapy induced an acute neutrophilic infiltrate, a relative decrease of ITu macrophages, and a myeloid cell-dependent upregulation of host-derived vascular endothelial growth factor (VEGF). Anti-VEGF antibodies, bevacizumab and r84, the latter of which binds VEGF and selectively inhibits binding to VEGF receptor-2 (VEGFR2) but not VEGFR1, enhanced the antitumor effects of virotherapy, in part due to decreased angiogenesis but not increased virus production. Neither antibody affected neutrophilic infiltration but both partially mitigated virus-induced depletion of macrophages. Enhancement of virotherapy-mediated antitumor effects by anti-VEGF antibodies could largely be recapitulated by systemic depletion of CD11b+ cells. These data suggest the combined effect of oHSV virotherapy and anti-VEGF antibodies is in part due to modulation of a host inflammatory reaction to virus. Our data provide strong preclinical support for combined oHSV and anti-VEGF antibody therapy and suggest that understanding and counteracting the innate host response may help enable the full antitumor potential of oncolytic virotherapy. 相似文献
68.
Purpose:?In this study we assessed whether balance confidence scores changed over a 2-year follow up period, and identified predictors of balance confidence and predictors of change in balance confidence among lower limb amputees.Method:?A prospective follow-up survey of 245 community living adults with unilateral below and above knee lower limb amputation who used their prosthetic limb daily was conducted. Balance confidence, assessed using the 16-item Activity-specific Balance Confidence (ABC) Scale, socio-demographic, health and amputation related variables were collected at baseline and 2 years later.Results:?ABC scores were similar at baseline (mean?= 67.6; SD?=?25.7) and follow up (mean?=?68.0; SD?=?25.8). Lower balance confidence scores at follow up were predicted by older age, being female, use of a mobility device, poor perceived health, increased symptoms of depression, having to concentrate while walking, and fear of falling (all p?<?0.05). Predictors of change in balance confidence included gender and perceived health (all p?<?0.05).Conclusion:?Balance confidence appears to be a persistent problem in the amputee population. Health professionals are encouraged to consider balance confidence as a potentially important variable that may influence function in this clinically unique group of individuals. The identified predictor variables may be useful to clinicians in targeting individuals who require attention to improve balance confidence. 相似文献
69.
Relationship between gastric cancer and precancerous lesions 总被引:3,自引:0,他引:3
RelationshipbetweengastriccancerandprecancerouslesionsMAJunLing1,LIUWeiDong2,ZHANGZaiZhen1,ZHANGLian3,YOUWeiCheng3andCHAN... 相似文献
70.