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991.
We investigated the effects of interleukin-4 (IL-4) on the survival of leukemic and normal B-cell progenitors cultured on bone marrow stroma. IL-4 (at 100 U/mL) was cytotoxic in 16 of 21 cases of B-lineage acute lymphoblastic leukemia, causing reductions in CD19+ cell numbers that ranged from 50% to greater than 99% (median 83.5%) of those in parallel cultures not exposed to the cytokine. All nine cases with the t(9;22)(q34;q11) or the t(4;11)(q21;q23), chromosomal features that are often associated with multidrug resistance and a fatal outcome, were susceptible to IL-4 toxicity. IL-4 cytotoxicity resulted from induction of programmed cell death (apoptosis); there was no evidence of cell killing mediated by T, natural killer, or stromal cells. IL-4 cytotoxicity extended to a proportion of normal B-cell progenitors. After 7 days of culture with IL-4 at 100 U/mL, fewer CD19+, CD34+ normal lymphoblasts (the most immature subset) survived: in five experiments the mean (+/- SEM) reduction in cell recoveries caused by IL-4 was 60.0% +/- 6.0%. By contrast, reductions in recovery of more differentiated bone marrow B cells (CD19+, CD34-, surface Ig+) were low (6.6% +/- 2.2%; P < .001 by t-test). Our findings indicate that IL-4 is cytotoxic for human B-cell precursors and support clinical testing of IL-4 in cases of high-risk lymphoblastic leukemia resistant to conventional therapy.  相似文献   
992.
Pui  CH; Ip  SH; Dodge  RK; Carrabis  S; Brown  M; Crist  WM; Berard  CW; Kung  P; Dahl  GV; Murphy  SB 《Blood》1988,72(3):1015-1021
Serum concentrations of CD8 antigen were measured at diagnosis with an enzyme-linked immunoassay in children with acute lymphoblastic leukemia (n = 344) or non-Hodgkin's lymphoma (n = 65). All patients had detectable levels of the serum antigen, which in its soluble nonreduced form appeared to be a 52-Kd homodimer as compared with the 66-Kd surface membrane component on most thymocytes and on a subset of functionally distinct T cells (suppressor/cytotoxic). Increased serum levels of CD8 in leukemia patients were significantly related to recognized high-risk prognostic features: high leukocyte count, large liver and spleen size, high serum lactic dehydrogenase level, T-cell immunophenotype, presence of a mediastinal mass, pseudodiploid karyotype, DNA index less than 1.16, and chromosomal translocation. Children with serum CD8 levels greater than or equal to 450 U/mL were more likely to fail treatment than were those with lower levels (P = .002), even in the group with non-T-cell leukemia (P = .003). In a multivariate analysis, serum CD8 antigen contributed independent prognostic information beyond that conveyed by age, leukocyte count, and race (P = .02). High serum CD8 antigen levels also correlated with advanced stages of disease in children with non-Hodgkin's lymphoma or B- cell leukemia. Children with higher serum CD8 antigen levels (greater than or equal to 700 U/mL) had a poorer treatment outcome (P = .003), even after results were adjusted for disease stage and serum lactic dehydrogenase level (P = .05). Measurement of serum levels of CD8 antigen not only has important prognostic value in childhood lymphoid malignancies but also could be useful in assessing the immunoregulatory role of T cells in patients with cancer.  相似文献   
993.
Leukemic cells from 89 (24%) of 369 children with newly diagnosed acute lymphoblastic leukemia (ALL) were found to have a pre-B immunophenotype. By comparison with blasts having the common ALL phenotype, the pre-B cells were more likely to have a DNA index less than 1.16 (P = 0.02), a pseudodiploid karyotype (P less than 0.001), and a chromosomal translocation (P = 0.001). Increased serum lactic dehydrogenase levels (P = 0.001) were also characteristic of pre-B ALL; otherwise, the clinical and laboratory features of the two groups were similar. A nonrandom chromosomal translocation, t(1;19)(q23;p13.3), was identified in blast cells from 16 (23%) of the 70 patients with pre-B ALL and adequate chromosome banding studies; different translocations were found in 11 of the remaining patients. The presence of any chromosomal translocation in the pre-B group was significantly related to a higher leukocyte count, an increased level of serum lactic dehydrogenase, an increased percentage of S-phase cells, black race, and a blast cell DNA index less than 1.16. Four presenting features were found to confer an increased risk of treatment failure among pre-B patients: pseudodiploidy, chromosomal translocation, black race, and higher serum lactic dehydrogenase level. In a multivariate analysis, pseudodiploidy emerged as the strongest factor for predicting relapse in pre-B ALL. The frequent association of chromosomal abnormalities of known adverse prognostic significance and high serum lactic dehydrogenase levels with pre-B-cell ALL explains, at least in part, the poor treatment outcome reported for children with this subtype of leukemia.  相似文献   
994.
995.
Enforced BCL-2 gene expression in leukemic cell lines suppresses apoptosis and confers resistance to anticancer drugs, but the clinical significance of increased BCL-2 protein levels in acute lymphoblastic leukemia (ALL) is unknown. Among 52 children with newly diagnosed ALL, BCL-2 expression in leukemic lymphoblasts ranged widely, from 4,464 to 59,753 molecules of equivalent soluble fluorochrome per cell (MESF), as determined by flow cytometry. The mean (+/- SD) level of MESF in 43 cases of B-lineage ALL (19,410 +/- 11,834) was higher than that detected in CD10+ B-lymphoid progenitors from normal bone marrow (450 +/- 314; P < .001), and CD19+ peripheral blood B lymphocytes (7,617 +/- 1,731; P = .02). Levels of BCL-2 in T-ALL cases (17,909 +/- 18,691) were also generally higher than those found in normal CD1a+ thymocytes (1,762 +/- 670), or in peripheral blood T lymphocytes (9,687 +/- 3,019). Although higher levels of BCL-2 corresponded to higher leukemic cell recoveries after culture in serum-free medium, they did not correlate with higher cell recoveries after culture on stromal layers, or with in vitro resistance to vincristine, dexamethasone, 6- thioguanine, cytarabine, teniposide, daunorubicin or methotrexate. BCL- 2 protein levels did not correlate with presenting clinical features. Unexpectedly, however, lower-than-median MESF values were significantly associated with the presence of chromosomal translocations (P = .010). Notably, all six cases with the Philadelphia chromosome, a known high- risk feature, had low levels of BCL-2 expression (P = .022). Higher levels of BCL-2 were not associated with poorer responses to therapy among 33 uniformly treated patients, and were not observed in three patients studied at relapse. In conclusion, increased BCL-2 expression in childhood ALL appears to enhance the ability of lymphoblasts to survive without essential trophic factors, and is inversely related to the presence of chromosomal translocations. However, it does not reflect increased disease aggressiveness or resistance to chemotherapy.  相似文献   
996.
The presence of clinically palpable finger joint nodules a(Heberden'sand Bouchard's nodes) was documented in 123 consecutive caseswith diffuse idiopathic skeletal hyperostosis (DISH) of thethoracic spine and 191 matched DISH negative controls. The prevalenceof palpable finger joint nodules was almost twice as frequentin cases with spinal DISH compared to controls (46% versus 31%,X2 = 7.67, P<0.01; multivariate adjusted odds ratio OR =1.84; 95% CI: 1.14–2.98). This increase was most markedat the proximal interphalangeal joint, in males and in patientsup to the age of 65 years. In addition and independent of othervariables such as hyperostotic features, age and sex, the prevalenceof palpable finger joint nodules was about twice as high inprobands with a history of physically heavy work compared tothose without (43% ver sus 26%, X = 9.18, P<0.005; multivariateadjusted odds ratio OR = 2.10; 95% CI: 1.26–3.52). Fromthese results we con clude that DISH should be considered asan independent risk factor in the development of finger jointnodules. KEY WORDS: Heberden's nodes, Diffuse idiopathic skeletal hyperostosis (DISH), Controlled study  相似文献   
997.
Tungstic acid reduction of cold-resistant stress-induced ulceration in rats   总被引:2,自引:0,他引:2  
Sprague-Dawley rats were restrained at 4°C for 2 h (stress). Tungstic acid in a single dose of 0.01, 0.1, 1, 10, 100 or 300 mg/kg (dissolved in distilled water) was administered intragastrically to animals 30 min prior to stress. Stress induced significant gastric mucosal damage, whereas tungstic acid pretreatment dose-dependently reduced lesion formation. Doses of tungstic acid of 1 mg/kg and higher significantly (P < 0.05–0.001) decreased ulcers. The mucosal mast cell counts in rats pretreated with tungstic acid were significantly higher than those of control rats. In motility experiments using oral administration of amberlite pellets, pretreatment with tungstic acid dose-dependently reduced the gastric emptying rate during a 1 h period of stress. Gastric mucosal xanthine oxidase and superoxide dismutase (SOD) activities, after pretreatment with a single dose of tungstic acid, were not altered in stressed animals. It is suggested that tungstic acid effectively antagonizes stress-induced gastric ulcers, possibly by decreasing motility and mass cell degranulation. Xanthine oxidase and SOD activities and mucous content were not changed in the gastric mucosa by the present method of tungstic acid administration.  相似文献   
998.
Approximately one fourth of children with newly diagnosed acute lymphoblastic leukemia (ALL) have hyperdiploid (greater than 50 chromosomes) blasts and a relatively favorable prognosis. Nonetheless, a substantial proportion of these patients fail therapy. We studied 138 children (70 male, 68 female) with hyperdiploid greater than 50 ALL to assess initial clinical and cytogenetic features that might predict treatment failure. In 85 of these cases (62%), structural chromosomal abnormalities were also present; clinical and laboratory features in this group did not differ from those of the 53 cases with only numeric abnormalities. However, of the 28 failures seen at a median follow-up of 4 years, 22 occurred in cases with structural chromosomal abnormalities (P = .03 by Breslow test). In a multivariate analysis, only the presence of structural chromosomal abnormalities and male gender were independently associated with treatment failure. Structural chromosomal abnormalities in cases of ALL with greater than 50 chromosomes may define a biologically different form of leukemia characterized by increased likelihood of drug resistance.  相似文献   
999.
Huang  CH; Guizzo  ML; Kikuchi  M; Blumenfeld  OO 《Blood》1989,74(2):836-843
Sta is an antigen of the human MNSs blood group system carried by a variant glycophorin residing in the erythrocyte membrane. We examined the structure, organization, and inheritance of Sta gene identified in genomic DNA from an Oriental family. Southern blotting detected a useful genetic marker tightly linked to the Sta gene. Differential hybridization and secondary restriction analyses showed that Sta gene is a fusion hybrid of delta and alpha glycophorin genes. Genomic mapping by extensive use of synthetic oligonucleotides, with overlapping sequence specificity, allowed us to define the delta-alpha junction site and disclose the organization of the variant gene. The junction point of Sta hybrid gene is encompassed by an unexpressed exonlike sequence of the delta gene at the 5' site, and an expressed sequence of the alpha gene spanning codons 59 through 71, at the 3' site. Dosage quantification demonstrated the occurrence of Sta gene as a single copy in the genome. Blood group inheritance, evaluated by DNA typing, established the tight linkage of Sta to the alpha M and delta S genes. The data support a single unequal crossing-over event between misaligned delta and alpha genes on the homologous chromosomes as the mechanism for the origin of Sta gene. The Sta gene is similar in overall structure to another delta-alpha hybrid gene, Dantu, but differs from it in junction structure, copy number, gene linkage, and antigen specificity.  相似文献   
1000.
弦式加载法延长面神经模型的建立   总被引:1,自引:1,他引:0  
目的 为使神经延长术更简便地应用于临床 ,尤其是用于面神经缺损的修复 ;同时更科学地研究周围神经的生物力学特性。方法 自行研制一种新的神经延长器 ,以弦式加载方式对面神经进行快速和缓慢延长 ,观察延长前后面神经的电生理及病理形态学变化。结果 延长器放置部位的组织无变性坏死 ,伤口及创面无感染 ,动物进食功能无障碍 ,体温不升高 ;病理学观察可见快速组神经出现散在的 Sunderland 度损伤 ,偶见毛细血管断裂 ,而缓慢组神经变粗 ,神经束间、外膜成纤维细胞增生 ;颊肌肌电图及神经传导速度检测显示 ,神经可延长极限快速组为 (18.7± 2 .4) % ,缓慢组为 (30 .8± 2 .4) % (均已除去回缩率 )。结论 所建立的神经延长模式和方法具有科学性和实用性 ,可用于神经延长的基础和临床研究。  相似文献   
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