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121.
Twenty-four adults with ALL were treated with AMSA alone or in combination. Twenty-two were treated at time of relapse and two patients after failing primary induction therapy. All had been treated with anthracyclines prior to receiving AMSA. Of the 22 patients with ALL in relapse, 4 achieved a complete remission. Two of these patients have relapsed while receiving maintenance chemotherapy; one died 1 mo after achieving remission due to the occurrence of cholycystitis in the setting of pancytopenia and one patient underwent bone marrow transplantation and is in remission at 8 mo after the second remission. Both patients who failed primary induction therapy remain in remission at 11 and 36 mo, respectively. The use of AMSA should be considered for patients with ALL who fail primary induction as well as those whose leukemia becomes resistant to conventional agents.  相似文献   
122.
A cell line, designated RS4;11, was established from the bone marrow of a patient in relapse with an acute leukemia that was characterized by the t(4;11) chromosomal abnormality. The cell line and the patient's fresh leukemic cells both had the t(4;11)(q21;q23) and an isochromosome for the long arm of No. 7. Morphologically, all cells were lymphoid in appearance. Ultrastructurally and cytochemically, approximately 30% of the cells possessed myeloid features. The cells were strongly positive for terminal deoxynucleotidyl transferase. They were HLA-DR positive and expressed surface antigens characteristic for B lineage cells, including those detected by anti-B4, BA-1, BA-2, and PI153/3. Immunoglobulin gene analysis revealed rearrangements of the heavy chain and kappa chain genes. The cells lacked the common acute lymphoblastic leukemia antigen and antigenic markers characteristic of T lineage cells. The cells reacted with the myeloid antibody 1G10 but not with other myeloid monoclonal antibodies. Treatment with 12-O-tetradecanoyl- phorbol-13-acetate induced a monocyte-like phenotype demonstrated by cytochemical, functional, immunologic, and electron microscopic studies. The expression of markers of both early lymphoid and early myeloid cells represents an unusual phenotype and suggests that RS4;11 represents a cell with dual lineage capabilities. To our knowledge, RS4;11 is the first cell line established from t(4;11)-associated acute leukemia.  相似文献   
123.
Peroxidase-H2O2-halide system: Cytotoxic effect on mammalian tumor cells   总被引:28,自引:0,他引:28  
Clark  RA; Klebanoff  SJ; Einstein  AB; Fefer  A 《Blood》1975,45(2):161-170
Myeloperoxidase, H2O2, and a halide constitute a potent antimicrobial system. A cytotoxic effect of this system on a line of mouse ascitic lymphoma cells (LSTRA) is demonstrated here using four different assay systems: 51Cr release, trypan blue exclusion, inhibition of glucose C-1 oxidation, and loss of oncogenicity for mice. Deletion of each component of the system, preheating the peroxidase, or addition of azide, cyanide, or catalase abolished the cytotoxicity. Myeloperoxidase was effective with either chloride or iodide as the halide, while lastoperoxidase was effective with iodide but not chloride. The iodinated thyroid hormones, triiodothyronine and thyroxine, could substitute for the halide, and H2O2 could be replaced by a peroxide- generating enzyme system such as glucose and glucose oxidase or by H2O2 producing bacteria such as pneumococci or streptococci. The possibility is raised that the peroxidases of inflammatory cells and certain biologic fluids may affect tumor initiation or growth in vivo.  相似文献   
124.
Sheibani  K; Forman  SJ; Winberg  CD; Rappaport  H 《Blood》1983,62(6):1176-1181
Although rare cases of chronic lymphocytic leukemia (CLL) of the T-cell type have been reported, CLL is more commonly found to be a neoplastic lymphoproliferative disease of B-cell origin. In this article, we describe a patient with long-standing CLL that was immunologically shown to be of the B-cell type, who, during the course of his disease, developed cutaneous T-cell lymphoma (CTCL), which was shown to be of the helper/inducer subtype. The neoplastic lymphoid cells in the skin infiltrate differed morphologically and immunologically from those in the peripheral blood. The occurrence of CTCL during this patient's clinical course represents a second neoplasm arising from a different cell line, rather than a tissue manifestation of the patient's CLL. To our knowledge, this is the first report in which the occurrence of CTCL is documented in a patient with immunologically known B-cell CLL. In addition to establishing the presence of B-cell CLL and CTCL of the helper/inducer T-cell type in the same patient, this case report demonstrates the usefulness and necessity of evaluating lymphoproliferative disorders by means of a multidisciplinary approach.  相似文献   
125.
Fraser  CC; Eaves  CJ; Szilvassy  SJ; Humphries  RK 《Blood》1990,76(6):1071-1076
A large number of biologic, technological, and clinical studies await the development of procedures that will allow totipotent hematopoietic stem cells to be expanded in vitro. Previous work has suggested that hematopoiesis can be reconstituted using transplants of cells from long- term marrow cultures. We have used retrovirus mediated gene transfer to demonstrate that marked totipotent hematopoietic stem cells are both maintained and can be amplified in such cultures, and then subsequently regenerate and sustain lympho-myeloid hematopoiesis in irradiated recipients. Marrow cells from 5-fluorouracil-treated male mice were infected with a recombinant virus carrying the neomycin resistence gene and seeded onto irradiated adherent layers of pre-established, long- term marrow cultures of female origin. At 4 weeks, cells from individual cultures were transplanted into single or multiple female recipients. Southern blot analysis of hematopoietic tissue 45 days posttransplantation showed retrovirally marked clones common to lymphoid and myeloid tissues in 14 of 23 mice examined. Strikingly, for 3 of 4 long-term cultures, multiple recipients of cells from a single flask showed marrow and thymus repopulation with the same unique retrovirally marked clone. These results establish the feasibility of retroviral-marking techniques to demonstrate the maintenance of totipotent lympho-myeloid stem cells for at least 4 weeks in the long- term marrow culture system and provide the first evidence of their proliferation in vitro. Therefore, such cultures may serve as a starting point for identifying factors that stimulate totipotent hematopoietic stem cell expansion.  相似文献   
126.
Schuster  SJ; Wilson  JH; Erslev  AJ; Caro  J 《Blood》1987,70(1):316-318
Although erythropoietin (Epo) is produced primarily by the kidneys in response to hypoxia, the precise cell type(s) and mechanisms by which these cells regulate production are poorly understood. In the experiments we report, the kinetics of renal Epo production in response to acute hypoxia and the intrarenal localization of cellular Epo synthesis were studied at the level of Epo mRNA. Erythropoietin mRNA expression was determined by Northern blot analysis of rat kidney RNAs using a probe derived from the mouse Epo gene. Renal Epo mRNA content increased as early as 1 hour after initiation of hypoxia and continued to accumulate during 4 hours of stimulation. Discontinuation of the hypoxic stimulus resulted in rapid decay of mRNA levels. Kidney and plasma Epo levels measured by radioimmunoassay paralleled, with respective lag times, the changes in renal Epo mRNA content, suggesting that Epo production in response to acute hypoxia represents de novo synthesis and is regulated by changes in Epo mRNA. Northern blot analysis of RNAs extracted from separated glomerular and tubular tissue fractions revealed Epo mRNA in the tubular fraction, whereas glomerular tissue did not contain Epo mRNA. Thus, the site of cellular Epo synthesis is located in the renal tubule or its interstitium and not in the glomerular tuft.  相似文献   
127.
This is the first controlled study of the frequency of backpain in a European caucasian population with diffuse idiopathicskeletal hyperostosis (DISH). Elderly patients admitted to hospital for reasons other thanback pain were assessed for the presence of spinal DISH usingthe routine lateral chest radiograph films. A total of 106 probands(82 males, 24 females) with a mean age of 70 years fulfilledthe criteria for DISH as defined previously. One hundred andseventyeight patients (117 males, 61 females) not meeting thesecriteria were used as controls. The prevalence of back painwas assessed by a blinded interviewer using a structured questionnaire.Our primary hymthesis was that spinal DISH positive probandshad not had back pain more often than controls. The controlledstudy showed no statistically significant difference in painfrequency between spinal DISH positive probands and controlsat any spinal level. We conclude that back pain does not occur more often in radiographicallydefined DISH positive probands than in controls. The radiologicalfinding of spinal DISH, as far as it does not lead to stenosisof the spinal canal or dysphagia, thus seems to be a findingwithout clinical relevance. KEY WORDS: Spine, Radiographs, Pain, Osteoarthritis, Forestier's disease, Ankylosing vertebral hyperostosis  相似文献   
128.
A recombinant endotoxin-neutralizing protein, rBPI23, was shown to partially prevent endotoxin-induced activation of the fibrinolytic and coagulation systems in experimental endotoxemia in humans. In a placebo- controlled, blinded crossover study, eight volunteers were challenged twice with an intravenous bolus injection of endotoxin (40 EU/kg of body weight) and concurrently received either rBPI23 (1 mg/kg) or placebo (human serum albumin, 0.2 mg/kg). rBPI23 treatment significantly lowered the endotoxin-induced fibrinolytic response, ie, reduced the release of tissue-type plasminogen activator, urokinase- type plasminogen activator, plasminogen activator inhibitor antigen, and complex formation of plasmin alpha 2-antiplasmin (P = .0078 for each). Plasminogen activator inhibitor activity was also reduced, but not significantly according to the Hochberg method (P = .0304). The endotoxin-induced activation of the procoagulant state as reflected by increase in F1 + 2 fragments and TAT complexes was blunted by rBPI23 infusion (P = .0391 [not significant according to the Hochberg method] and .0078, respectively). These results indicate that rBPI23 is capable of reducing both the activation of the fibrinolytic and the coagulation systems after low-dose endotoxin infusion in humans.  相似文献   
129.
We report the treatment outcome of allogeneic bone marrow transplantation in ten patients with Philadelphia chromosome-positive acute lymphoblastic leukemia. Six patients are alive and well for 6 to 30 months (median 19 months) after transplantation. Four patients died with transplant related complications. In view of the poor prognosis associated with this disease, marrow ablation followed by allogeneic or syngeneic marrow grafting may be the preferred treatment modality if a suitable marrow donor is available.  相似文献   
130.
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