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991.
BACKGROUND: The transfusion of same-donor peripheral blood buffy coat (PBBC) cells to chronic myelocytic leukemia patients in relapse after bone marrow transplantation has been increasingly used as an effective antileukemic therapy. A graft-versus-leukemia effect mediated by immunocompetent donor T cells underlies its success. In acute leukemia, however, the effect of this adoptive cellular immunotherapy has not been established, and the results are generally poor. STUDY DESIGN AND METHODS: Five patients, three with acute lymphoblastic leukemia and two with acute myelocytic leukemia, who relapsed within 6 months after allogeneic marrow transplantation were enrolled in a nonrandomized pilot study to receive donor PBBC cell transfusions either before or after undergoing cytoreductive chemotherapy. ABO genotyping and polymerase chain reaction amplification of human tetrameric short tandem repeats DNA typing were used to test for marrow chimerism. RESULTS: Two acute lymphoblastic leukemia patients-both of whom underwent chemotherapy before PBBC cell transfusions, experienced a complete remission, and developed acute and then chronic, extensive graft-versus-host disease-have been leukemia-free for 9 and 7 months, respectively. Repeated molecular studies of their marrow as early as 2 weeks to 8 months after treatment confirmed that the marrow was of donor origin. The other three patients, who chose not to undergo chemotherapy before PBBC cell transfusions, failed to achieve remission and died 14, 16, and 30 days, respectively, after leukemia relapse. CONCLUSION: Adoptive cellular immunotherapy may be effective for acute lymphoblastic leukemia patients in relapse after bone marrow transplantation if chemotherapy is administered before PBBC cell transfusions are initiated. 相似文献
992.
Nicholas JC Smith Maria Fuller Jennifer T Saville Timothy M Cox 《The Journal of pathology》2018,244(1):120-128
The glycosphingolipidosis, Gaucher disease, in which a range of neurological manifestations occur, results from a deficiency of acid β‐glucocerebrosidase, with subsequent accumulation of β‐glucocerebroside, its upstream substrates, and the non‐acylated congener β‐glucosylsphingosine. However, the mechanisms by which end‐organ dysfunction arise are poorly understood. Here, we report strikingly diminished cerebral microvascular density in a murine model of disease, and provide a detailed analysis of the accompanying cerebral glycosphingolipidome in these animals, with marked elevations of β‐glucosylsphingosine. Further in vitro studies confirmed a concentration‐dependent impairment of endothelial cytokinesis upon exposure to quasi‐pathological concentrations of β‐glucosylsphingosine. These findings support a premise for pathogenic disruption of cerebral angiogenesis as an end‐organ effect, with potential for therapeutic modulation in neuronopathic Gaucher disease. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
993.
WJ Judd ; EA Steiner ; LV Abruzzo ; RD Davenport ; HA Oberman ; JC Pehta ; SJ Nance 《Transfusion》1992,32(6):572-575
A unique case of acute hemolysis following transfusion of red cells (RBCs) that were found compatible by immediate-spin (IS) crossmatch technique is reported. Screening tests for unexpected antibodies, using low-ionic-strength saline (LISS), 10 minutes' incubation at 37 degrees C, and anti-IgG, were nonreactive; however, 1 transfused unit was found crossmatch incompatible by indirect antiglobulin technique (IAT). An anti-i (titer 512 at 4 degrees C) that was not an autoantibody was identified in the patient's serum. Unlike the incriminated donor RBCs, most I+ RBCs did not react by LISS-IAT. Variable reactivity was seen with ficin-treated I+ RBCs, and there was marked hemolysis of iadult and icord RBCs. In marked contrast, dominant Lu(a-b-) RBCs, with reduced expression of i, did not react by any test method; nor did autologous I+, Lu(b+) RBCs. The in vivo clinical significance of this anti-i was confirmed by monocyte monolayer assay and RBC survival studies. The patient's i antigen may have been altered, by either chemotherapy or disease, and lacked part of the i antigen-mosaic. Her antibody was directed at epitopes of i that were absent from her RBCs. Those i epitopes missing from her RBCs are also absent on dominant Lu(a-b-) RBCs. This anti-i represents a unique cause of an acute hemolytic transfusion reaction. It also represents a case of acute immune-mediated hemolysis following transfusion of IS crossmatch-compatible blood when screening tests for unexpected antibodies are nonreactive. Because of the rarity of such cases (less than 1/200,000 RBC units transfused), modifications to pretransfusion testing protocols are not proposed. 相似文献
994.
JO Bordin ; J Kerbauy ; JC Souza-Pinto ; E Conti ; CA Accetturi ; MA Kishiwada ; NF Novo ; A Castelo 《Transfusion》1992,32(5):426-429
Anemia, thrombocytopenia, and neutropenia have been observed in patients with acquired immune deficiency syndrome (AIDS) and AIDS-related complex. To investigate whether red cells (RBCs) of patients with human immunodeficiency virus infection were coated with IgG and/or complement (C3), blood samples of 239 patients were tested. The prevalence of a positive direct antiglobulin test on RBCs was 16.7 percent. By use of an enzyme-linked antiglobulin test (ELAT) to measure more accurately the number of IgG molecules per RBC in a group of 67 patients, 30 of the 67 individuals were observed to have increased numbers (mean, 155) compared to normal controls and to patients with hypergammaglobulinemia due to multiple myeloma or chronic liver disease. Hemoglobin level was correlated with the number of IgG molecules per RBC (p = 0.008), but no correlation could be demonstrated between those numbers and serum immunoglobulin (p = 0.10) or circulating immune complexes (p = 0.38). Our results with ELAT suggest that some AIDS patients may have specific binding of IgG on the surface of their RBCs, rather than nonspecific uptake; further clinical correlations are necessary to confirm these findings. 相似文献
995.
B-cell tolerance. IV. Differential role of surface IgM and IgD in determining tolerance susceptibility of murine B cells 下载免费PDF全文
ES Vitetta JC Cambier FS Ligler Kettman JR JW Uhr 《The Journal of experimental medicine》1977,146(6):1804-1808
During ontogeny IgD appears later than IgM on splenocytes of neonatal mice (1) and at a time when mice develop a markedly increased immune responsiveness (2). Based on these observations, it was suggested that IgD serves as a “triggering” isotype for induction of immune responses, whereas surface IgM functions as a tolerizing receptor (3). To test this hypothesis, the susceptibility of adult splenocytes (which are predominantly μ(+)δ(+)[4-6]) and neonatal splenocytes (which bear predominantly IgM [μp(+); 1, 4-6]) to tolerance induction were compared. The results indicate that neonatal splenic B cells responsive to thymus dependent (TD) antigens are exquisitely susceptible to tolerance induction compared with those from adult mice (7-9). However, cells from both adult and neonatal mice were highly susceptible to tolerance induction when thymus independent (TI) antigen was used as immunogen (8). These results suggest that the major precursor for the TD response is a μ(+)δ(+)-cell which appears late in ontogeny and is resistant to tolerance induction and that the μp(+)-cell is the major precursor for the TI response and is highly susceptible to tolerance induction. Other differences between responders for TI and TD antigens have been described previously (10-12). To test this concept, adult splenocytes were treated with papain under conditions in which IgD, but not five other surface molecules, was removed (13). Such treated splenocytes were shown to be markedly susceptible to tolerance induction, resembling TD responders from neonatal animals. This experiment was interpreted as indicating that IgD confers resistance to tolerance induction on μ(+)δ(+)-cells. To prove this interpretation, it is necessary to show that specific removal of IgD with anti-δ also results in increased susceptibility to tolerance induction and that treatment with anti-μ does not have a similar effect. In the present studies, we have removed surface IgM or IgD by antibody-induced capping and assessed the tolerance susceptibility of the treated cells. Our results demonstrate that removal of IgD, but no IgM, from TD responders increases their susceptibility to tolerance induction. 相似文献
996.
中国病毒性乙型肝炎的研究 总被引:9,自引:9,他引:0
我国是病毒性乙型肝炎(HB)高发病国家,人群感染HBV约有6.5亿,而HBsAg慢性携带者则为1.2亿,每年死于HB及相关性疾病者在16万人以上,HB已成为我国危害最大的社会公共卫生问题。现就目前我国HB研究的状况,提出一些思考,希望能对HB的研究有所助益。 1 病毒性乙型肝炎的分类我国现行的病毒性肝炎分类方案(以下称分类方案)与国际上基本一致,将其分为急性、慢性和肝炎肝硬变三大类,又根据HB不同的临床体征及组织病理学表现,而分成若干亚型。 相似文献
997.
分光光度法测定金蝉花中多糖的含量 总被引:6,自引:0,他引:6
目的建立金蝉花药材中多糖的含量测定方法.方法采用分光光度法测定多糖含量.结果金蝉花中多糖含量为24.16 mgg-1,平均回收率为97.37%,RSD=2.34%,n=5.结论本法简便、准确、灵敏、重现性好,为金蝉花药材的质量控制提供了依据. 相似文献
998.
JC Richard C Pouzot A Gros C Tourevieille D Lebars F Lavenne I Frerichs C Guérin 《Critical care (London, England)》2009,13(3):R82-9
Introduction
Electrical impedance tomography (EIT), which can assess regional lung ventilation at the bedside, has never been compared with positron-emission tomography (PET), a gold-standard to quantify regional ventilation. This experiment systematically compared both techniques in injured and non-injured lungs. 相似文献999.
作者运用生物素标记的山羊抗人巨噬细胞甘露糖受体(GoatAnti-humanMacrophageMannoseReceptor,AMMR)IgG对人获得能精子膜上的甘露糖结合蛋白进行定位,经激光共聚焦显微镜分析结果显示:AMMRIgG组阳性率显著高于运用正常山羊(NormalGoat,NG)IgG的对照组:AMMRIgG组的阳性率大约在70%(69.41%)左右,而NG IgG对照组中除少量精子显 相似文献
1000.
L Ylisastigui S Amzazi Y Bakri J Vizzavona C Vita JC Gluckman A Benjouad 《Biomedicine & Pharmacotherapy》1998,52(10):447-453
The effect of β chemokines on human immunodeficiency virus type I (HIV-1) infection of primary macrophages is controversial, and their effect on HIV-2 infection of these cells has not yet been documented. We examined the effect of synthetic and recombinant regulated-on-activation, normal T cell-expressed and -secreted (RANTES) on HIV-1 and HIV-2 infection of primary monocyte-derived-macrophages (MDM) that were obtained as the adherent cells of 5-day cultures of blood mononuclear cells (PBMC), followed by 2-day culture without peripheral blood mononuclear cells (PBMCs) nor added cytokines. These MDM expressed CD4, CCR5 and CXCR4, the major coreceptors for HIV macrophage- and T cell-tropic isolates, respectively. Infection of MDM from different donors with HIV-1 or HIV-2 macrophagetropic strains was reproducibly inhibited by RANTES. This inhibition depended on RANTES continuous presence in culture during and after infection. Treatment of MDM with RANTES just before or during, but not after, exposure to virus did not protect MDM from infection. When RANTES was added after MDM had been infected, and was continuously maintained in culture thereafter, no inhibition occurred and limited enhancement of infection could be observed. These data indicate that RANTES inhibits HIV-1 as well as HIV-2 infection of MDM, likely at a post-binding step, and support the role of CCR5 as the major coreceptor for HIV-1 and HIV-2 entry into primary macrophages. 相似文献