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121.
Molecular characterization of human factor XSan Antonio   总被引:1,自引:0,他引:1  
Reddy  SV; Zhou  ZQ; Rao  KJ; Scott  JP; Watzke  H; High  KA; Jagadeeswaran  P 《Blood》1989,74(5):1486-1490
Enzymatic amplification technique was used to isolate all eight exons and sequences around the splice junctions, putative promoter, and polyadenylation sites of human factor X DNA from a patient with factor X deficiency. Two genetic changes in factor X have been observed in this patient. The patient is most likely a compound heterozygote since there is only 14% activity associated with factor X. A point mutation that resulted in the substitution of cysteine (TGC) for arginine (CGC) at amino acid 366 was found in exon VIII of one allele of the factor X gene. This mutation, which occurs in the catalytic domain, can affect the formation of a disulfide bridge and thus could result in a reduction in factor X activity. Sequencing all the regions revealed a second mutation: a deletion of one nucleotide (TCCT to TCT) in exon VII that would cause a frame shift at amino acid 272 followed by termination. We have also shown that the point mutation in exon VIII creates an ApaL1 restriction site and destroys the HinP1 site. Enzymatic DNA amplification followed by restriction digestion provides a quick, reliable, and sensitive method for carrier detection and antenatal diagnosis in affected kindreds. This is the first characterization of factor X deficiency at the molecular level. We propose to name this mutation Factor XSan Antonio.  相似文献   
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In 990, Anhalt et al described a newly autoimmune billious disease: paraneoplastic pemphigus, in five patients. It was characterized by a distinct set of circulating autoantibodies from those in the sera of patients with pemphigus vulgaris and superficial pemphigus. We report a 7 year-old man with chronic lymphocytic leukemia of years duration who developed a severe mucocutaneous eruption with clinical and immunofluorescence findings of pemphigus vulgaris evolving into an oral bullous lichen planus presentation. Evaluation of his serum confirmed the presence of autoantibodies specific for paraneoplastic pemphigus by indirect immunofluorescence on rat-bladder and immunoprécipitation. Subsequently, additional cases have been reported in the literature. All occured in patients with various neoplastic conditions. These patients present with polymorphous skin lesions and severe erosive oral disease. Histologic examination shows interface dermatitis and keratinocyte necrosis in addition to acantolysis. Direct immunofluorescence may reveal deposition of immunoglobulin and/or complement at the basement membrane as well as deposition on epithelial cell surfaces. Circulating IgG anti-cell-surface antibodies are detectable with both stratified and stratified epithelia as substrates. These antibodies immunoprecipitate a complex of four desmosomal proteins, including desmoplakin I (50 kDa), the bullous pemphigoid antigen (0 kDa), desmoplakin II (0 kDa) and a 90 kDa antigen.  相似文献   
125.
From March 1988 to March 1991, 19 French bone marrow transplant (BMT) centers participated in a prospective randomized trial comparing two conditioning regimens for patients with chronic myeloid leukemia transplanted in first chronic phase with an HLA identical sibling donor. A total of 120 consecutive patients were randomized to receive either 120 mg/kg of cyclophosphamide followed by total body irradiation (CY-TBI; n = 55) or 16 mg/kg of busulfan followed by 120 mg/kg of CY (BU-CY; n = 65). Two different TBI regimens were used. Thirteen patients received a 10-Gy single-dose TBI (SDTBI), and 42 received a fractionated TBI (FTBI). Median time between diagnosis and BMT was 315 days. Overall 5-year actuarial survival was 62.9% (65.8% +/- 12.5% for CY-TBI and 60.6 +/- 11.7% for BU-CY; P = .5), and overall disease-free survival was 55% (51% +/- 14% for CY-TBI and 59.1% +/- 11.8% for BU-CY; P = .75). All patients conditioned with CY-TBI experienced sustained engraftment; in contrast, 4 of 65 patients conditioned with BU-CY rejected the graft (P = .18). There was no significant statistical difference between the two groups regarding transplant-related mortality (29% for CY-TBI and 38% for BU-CY; P = .44). So far, with a median follow up of 42 months, 11 patients have relapsed; 9 relapses occurred after CY-TBI, mostly after FTBI (8 of 9) and 2 after BU-CY (P = .02). The actuarial risk of relapse was 4.4% +/- 6.7% after BU-CY, 11.1% +/- 20.8% after SDTBI, and 31.3% +/- 18.1% after FTBI (P = .039). In addition, independently of the conditioning regimen, the increase of posttransplant immunosuppression in 16 patients with an anti- interleukin-2 receptor monoclonal antibody (MoAb) in addition to a short course of methotrexate and cyclosporine was shown to increase the actuarial risk of relapse (57% +/- 30% with MoAb v 9% +/- 7.3% without MoAb; P = .001). We conclude that BU is an acceptable alternative to TBI for patients with chronic myeloid leukemia in first chronic phase receiving BMT from HLA identical sibling donors. Both BU-CY and CY-TBI regimens gave similar transplant-related mortality, and the antileukemic efficiency of BU-CY regimen was either similar or even higher than that of CY-TBI.  相似文献   
126.
One mechanism proposed to play a role in T-cell depletion in human immunodeficiency virus (HIV) infection is apoptosis (activation-induced cell death). We assessed whether apoptosis is related to activation of T cells in vivo and its possible triggers. DNA was extracted from peripheral blood mononuclear cells (PBMC) taken from 16 vertically HIV- infected children and 9 HIV-negative children born to HIV-positive mothers (controls) and tested by agarose gel electrophoresis for the presence of DNA fragments specific for apoptosis. Signs of apoptosis were found on in vitro culture of PBMC from 12 of 16 HIV-infected children, but not in PBMC from the nine controls. Eleven of the 12 HIV- infected children with apoptosis showed an elevated (> 15%) proportion of CD3+/HLA-DR+ cells. This was due to an increased proportion of CD8+/HLA-DR+ cells, as shown in 7 of 7 further tested patients. In none of the probands an increased (> 5%) proportion of IL-2 receptor expressing CD3+ cells was found. T cells undergoing apoptosis were preferentially of the CD8+ phenotype. Expansion of circulating CD8+/interleukin-2 receptor (IL-2R)-/HLA-DR+ T cells is known to occur during active infection with herpes viruses. To investigate the possible role of herpes viral coinfections for apoptosis in HIV infection, we focused on Epstein-Barr virus (EBV) as an example for a herpes virus usually acquired during childhood. In 10 of 12 patients with apoptosis, we found increased levels of EBV genome in PBMC and/or tissues, indicating active EBV replication. By contrast, no increased burden of EBV was found in the four HIV-infected patients without apoptosis or in the controls. Our data indicate that in children the occurrence of apoptosis in HIV infection is closely related to activation of CD8+ T cells. Furthermore, primoinfection with or reactivation of herpes viruses, such as EBV, may substantially contribute to such T-cell activation and the ensuing apoptosis. Additional studies are warranted to evaluate the contribution of herpes virus-triggered apoptosis to the T-cell loss leading to the acquired immunodeficiency syndrome.  相似文献   
127.
A prospective, randomized trial was initiated in adult acute lymphoblastic leukemia (ALL) to compare (1) disease-free survival (DFS) after allogeneic or autologous bone marrow transplantation (BMT) and (2) the relapse rate of patients treated with or without interleukin-2 (IL-2) after autologous BMT. A total of 135 previously untreated patients, aged under 55 years, received the Berlin-Frankfurt-Muster (BFM) induction regimen: 126 patients (93%), of which 120 were HLA- typed, achieved complete remission (CR). According to this genetic randomization, patients with (n = 43) or without an HLA-identical sibling (n = 77) were to receive allogeneic or autologous BMT, respectively. The 3-year post-CR probability of DFS was significantly higher in the HLA-identical sibling group than in the non-HLA-identical sibling group (68% v 26%; P < .001). Eligible patients were randomized to receive (n = 30) or not to receive (n = 30) IL-2 after autologous BMT: the 3-year post-BMT probability of continuous CR was similar in both groups (29% v 27%, respectively). We conclude that, in ALL, early allogeneic BMT after the BFM induction regimen is an effective consolidation treatment and that IL-2 does not decrease the high relapse rate observed after autologous BMT.  相似文献   
128.
Fast  LD; Valeri  CR; Crowley  JP 《Blood》1995,86(8):3090-3096
Graft-versus-host disease (GVHD) is currently encountered after bone marrow transplantation and transfusion. GVHD associated with transfusion (TA-GVHD) in apparently immunocompetent recipients has been recently reported with increasing frequency. A consistent finding in many of these cases is that the recipient received blood from a donor homozygous for one of the recipient's HLA haplotypes. However, the observed frequency of TA-GVHD is much lower than the estimated probability of this donor/recipient combination. The potential role of recipient immune responses in controlling TA-GVHD was investigated using an analogous murine model in which GVHD is induced by the injection of parental lymphoid cells into unirradiated F1 hybrid recipients. The effect of various immune manipulations of the recipient of GVHD induction was assessed by determining the number of donor lymphoid cells required to induce GVHD responses. Whereas depletion of recipient CD4+ cells increased the number of donor cells needed to induce GVHD, depletion of recipient CD8+ and natural killer cells resulted in fewer donor cells being needed to induce a GVHD response. These studies suggest a central role for functioning recipient CD8 and natural killer cells in the down-regulation of TA-GVHD development in recipients.  相似文献   
129.
Assessment of aldehyde dehydrogenase in viable cells   总被引:3,自引:4,他引:3  
Cytosolic aldehyde dehydrogenase (ALDH), an enzyme responsible for oxidizing intracellular aldehydes, has an important role in ethanol, vitamin A, and cyclophosphamide metabolism. High expression of this enzyme in primitive stem cells from multiple tissues, including bone marrow and intestine, appears to be an important mechanism by which these cells are resistant to cyclophosphamide. However, although hematopoietic stem cells (HSC) express high levels of cytosolic ALDH, isolating viable HSC by their ALDH expression has not been possible because ALDH is an intracellular protein. We found that a fluorescent aldehyde, dansyl aminoacetaldehyde (DAAA), could be used in flow cytometry experiments to isolate viable mouse and human cells based on their ALDH content. The level of dansyl fluorescence exhibited by cells after incubation with DAAA paralleled cytosolic ALDH levels determined by Western blotting and the sensitivity of the cells to cyclophosphamide. Moreover, DAAA appeared to be a more sensitive means of assessing cytosolic ALDH levels than Western blotting. Bone marrow progenitors treated with DAAA proliferated normally. Furthermore, marrow cells expressing high levels of dansyl fluorescence after incubation with DAAA were enriched for hematopoietic progenitors. The ability to isolate viable cells that express high levels of cytosolic ALDH could be an important component of methodology for identifying and purifying HSC and for studying cyclophosphamide-resistant tumor cell populations.  相似文献   
130.
The hyperimmunoglobulinemia D and periodic fever (hyper-IgD) syndrome is typified by recurrent febrile attacks with abdominal distress, joint involvement (arthralgias/arthritis), headache, skin lesions, and an elevated serum IgD level (> 100 U/mL). This familial disorder has been diagnosed in 59 patients, mainly from Europe. The pathogenesis of this febrile disorder is unknown, but attacks are joined by an acute-phase response. Because this response is considered to be mediated by cytokines, we measured the acute-phase proteins C-reactive protein (CRP) and soluble type-II phospholipase A2 (PLA2) together with circulating concentrations and ex vivo production of the proinflammatory cytokines interleukin-1 alpha (IL-1 alpha), IL-1 beta, IL-6, and tumor necrosis factor alpha (TNF alpha) and the inhibitory compounds IL-1 receptor antagonist (IL-1ra), IL-10, and the soluble TNF receptors p55 (sTNFr p55) and p75 (sTNFr p75) in 22 patients with the hyper-IgD syndrome during attacks and remission. Serum CRP and PLA2 concentrations were elevated during attacks (mean, 213 mg/L and 1,452 ng/mL, respectively) and decreased between attacks. Plasma concentrations of IL-1 alpha, IL-1 beta, or IL-10 were not increased during attacks. TNF alpha concentrations were slightly, but significantly, higher with attacks (104 v 117 pg/mL). Circulating IL-6 values increased with attacks (19.7 v 147.9 pg/mL) and correlated with CRP and PLA2 values during the febrile attacks. The values of the antiinflammatory compounds IL-1ra, sTNFr p55, and sTNFr p75 were significantly higher with attacks than between attacks, and there was a significant positive correlation between each. The ex-vivo production of TNF alpha, IL-1 beta, and IL-1ra was significantly higher with attacks, suggesting that the monocytes/macrophages were already primed in vivo to produce increased amounts of these cytokines. These findings point to an activation of the cytokine network, and this suggests that these inflammatory mediators may contribute to the symptoms of the hyper-IgD syndrome.  相似文献   
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