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101.
102.
Ways DK; Qin W; Riddle RS; Garris TD; Bennett TE; Steelman LS; McCubrey JA 《Blood》1991,78(10):2633-2641
FD/PMA is a subclone of the interleukin-3 (IL-3)-dependent, FDC-P1 cell line, which proliferates in response to either 12-O- tetradecanoylphorbol-13 acetate (PMA) or IL-3. While several endogenous substrates were phosphorylated in response to protein kinase C (PKC) activation in FDC-P1, phospholipid-dependent phosphorylation in the FD/PMA grown in PMA was not observed. Basal, phosphatidylserine- independent, and diolein-independent phosphorylation of cytosolic substrates with molecular weights of 17, 52, 57, and 105 Kd were enhanced in FD/PMA cells grown in PMA as compared with FDC-P1 cells cultured in IL-3. Phosphorylation of a 105-Kd substrate was enhanced in the particulate fraction of FD/PMA cells maintained in PMA. The 17-Kd substrate in FD/PMA cells comigrated with a substrate phosphorylated in a PKC-dependent manner in FDC-P1 cells. Phosphorylation of the 52- and 57-Kd substrates, but not of the 17-Kd substrate, was inhibited by H-7 and staurosporine. A portion of the PMA-induced cytosolic kinase activity coeluted with PKC on diethyl aminoethyl chromatography. While FD/PMA cells cultured in PMA contained negligible PKC-dependent phosphorylation of endogenous substrates or histone, alpha and epsilon PKC isoforms were detected by Western blot analysis. PKC phosphotransferase activity was observed in FD/PMA cells grown in PMA when peptides corresponding to residues 720 to 737 of PKC-epsilon or residues 4 to 14 of myelin basic protein were used as substrates. These data indicate that maintenance of FD/PMA cells in PMA stimulates proliferation and markedly alters PKC substrate specificity. Generation of at least two phospholipid-independent kinases occurs in PMA-treated cells. 相似文献
103.
Somatic cell hybrid analyses of hematopoietic differentiation 总被引:1,自引:0,他引:1
A differentiated cell expresses an entire set of specialized features. Somatic cell hybridization provides a method to examine control of gene regulation. We studied the expression of tissue-specific features in hybrids between human promyelocytes (HL-60) and human Burkitt's lymphoma cells (P3HR-1). Two hybrid lines, HP-1 and HP-2, and 18 hybrid clones were established and confirmed by karyotype, isozyme, and surface antigen analyses. The hybrids extinguished the 10 myeloid (HL- 60) features that we examined including myeloid morphology, histochemistry, and functions that included response to colony- stimulating factor and ability to differentiate to granulocytes or macrophages. In contrast, the hybrids synthesized immunoglobulin and expressed Epstein-Barr nuclear, early, and viral capsid antigens similar to the P3HR-1 lymphoid parental line. Results are contrasted to the findings when P3HR-1 lymphocytes are fused to human erythroid- myeloid cells (K562). Taken together, our results suggest that phenotypic differences between human myeloid and lymphoid cells in the hematopoietic lineage involve mutually exclusive programs and may possibly be mediated by the activity of diffusible, transacting molecules. 相似文献
104.
Chronic myelocytic leukemia (CML) may display a lymphoproliferative phase (lymphoid blast crisis) that is generally of B cell phenotype. Since lymphoproliferative disorders may occur following bone marrow transplantation (BMT), it may be difficult to distinguish posttransplant relapse of CML lymphoid blast crisis from de novo lymphoproliferation. Lymphoid blast crisis cells from a patient with CML displayed immunoglobulin heavy chain gene (C mu) rearrangement before BMT. Following BMT the patient developed a lymphoproliferative disorder involving multiple organs. Clonal rearrangement of C mu was demonstrated in several involved tissues. The rearranged C mu restriction fragment was distinct from that displayed before BMT. Additionally, rearrangement of the breakpoint cluster region (bcr) was demonstrated in the pretransplant blast crisis sample, but not in the posttransplant lymphoproliferation samples, thus confirming that these lymphoproliferative disorders were distinct. Molecular genetic techniques offer powerful diagnostic tools for monitoring the course of patients with CML undergoing BMT. 相似文献
105.
Identification of cytidine diphosphodiesters in erythrocytes from a patient with pyrimidine nucleotidase deficiency 总被引:1,自引:0,他引:1
Pyrimidine 5'-nucleotidase deficient (PND) erythrocytes contain elevated levels of pyrimidine nucleotides and relatively normal purine nucleotide levels. The composition of this nucleotide pool has been examined by others, but not all of the abnormal red cell metabolites in this disorder were identified. We have isolated and positively confirmed the identity of cytidine diphosphate (CDP)-choline and CDP- ethanolamine from PND red cells using methods including proton FT-NMR, spectroscopy, and comparative mass spectrometry. The concentrations of these and other pyrimidine nucleotidase-deficient erythrocyte nucleotides were determined using anion-exchange high performance liquid chromatography and ultraviolet (u.v.) detection. The pyrimidine diphosphodiesters appear to be the most prominent abnormal pyrimidine nucleotides in PND red cells, accounting for 55% of the total red cell pyrimidine nucleotides in this disorder. It is proposed that these abnormal phosphodiesters may be related to the accelerated hemolysis in PND. 相似文献
106.
Alan N. Langnas D.O. Rodney S. Markin M.D. Masaru Inagaki M.D. Robert J. Stratta M.D. Michael F. Sorrell M.D. Jeremiah P. Donovan M.D. Byers W. Shaw Jr. M.D. 《The American journal of gastroenterology》1994,89(7):1066-1070
Objectives: The purpose of this study was to review our experience with tipstein-Barr virus (EBV) hepatitis after liver transplantation. Methods: During a 68–month period, we performed 668 liver transplants and 585 patients. We identifled 11 patients (2 percent), including 5 adults and 6 children with EBV hepatitis after liver transplantation. The diagnosis of EBV hepatitis was established by evaluating allograft biopsies. the histology was confirmed by the use of polymerase chain reaction technology. Results: The average time of diagnosis after liver transplantation was 45 days. Eight of eleven cases occurred within the first six months after transplantation. After the diagnosis of EBV hepatitis, treatment consisted of a decrease in immunosuppression plus antiviral therapy and intravenous immunoglobulin. The one-year actuarial survival for patients with EBV hepatitis, was 73 percent (8 of 11). Two patients died of progressive multi-organ EBV involvement. To determine the risk of developing EBV hepatitis, we reviewed our experience with the administration of antilympho-cyte preparations in 585 patients. the patients found to have a significantly greater risk of developing EBV hepatitis included those receiving more than one course of antilymphocyte therapy or greater than a total dose of 70 milligrams of OKT3 in a single course. Conclusions: EBV hepatitis after liver transplantation is an infrequent event, which may be treated successfully. The occurrence of EBV hepatitis appears closely linked to the use of antilymphocyte preparations. 相似文献
107.
H P Monsour E M Quigley R S Markin D D Dalke J C Goldsmith R F Harty 《Journal of clinical gastroenterology》1991,13(1):20-24
Two cases of mycobacterium avium-intracellulare (MAI) infection in association with acquired immunodeficiency syndrome (AIDS) are presented to highlight the distinctive upper gastrointestinal endoscopic appearances: 2 X 4 mm diameter, white nodules with intervening erythema and hemorrhagic erosions covered the mucosa of the second part of the duodenum. Histological evaluation of these nodules revealed diffuse expansion of the lamina propria by macrophages that contained numerous intracellular and extracellular acid-fast organisms. We conclude that endoscopy with endoscopic biopsy may represent the most rapid and sensitive diagnostic tool available in this disease. 相似文献
108.
J R Newland R S Markin R B Wilson J W Jones 《Journal of clinical gastroenterology》1989,11(4):461-463
A case of heterotopic liver of the jejunum confirmed by electron microscopy in a 2-year-old girl is described. We review the literature regarding heterotopic liver and discuss its embryogenesis. We suggest that in our case, there was trapping of hepatocyte-destined mesenchyme prior to biliary tree development. 相似文献
109.
Snyder DS; Negrin RS; O'Donnell MR; Chao NJ; Amylon MD; Long GD; Nademanee AP; Stein AS; Parker PM; Smith EP 《Blood》1994,84(5):1672-1679
Ninety-four consecutive patients with chronic myelogenous leukemia in first clinical chronic phase, median age of 34.0 years (range, 6.8 to 52.4 years), with a histocompatible sibling donor, were treated with fractionated total body irradiation (1,320 cGy) and high-dose etoposide (60 mg/kg) followed by allogeneic bone marrow transplantation (BMT). The median time from diagnosis to BMT was 7.0 months (range, 2.3 to 72.0 months). Sixty patients were treated before BMT with hydroxyurea alone, four patients with busulfan alone, one patient with interferon alone, and the other 29 patients were treated with various combinations of these drugs. Cumulative probabilities of overall survival, event- free survival, and relapse at 5 years were 73%, 64%, and 14%, respectively. The median follow-up time for surviving patients was 38 months, ranging from 12 to 88 months. By stepwise Cox regression analysis, significant prognostic variables were age at transplant, acute graft-versus-host disease > or = grade II, cytomegalovirus- associated interstitial pneumonitis, and years from diagnosis to BMT. 相似文献
110.
Chronic myelocytic leukemia (CML) is a clonal disorder involving neutrophil, monocyte, erythrocyte, and platelet precursors. In order to determine if the eosinophils are also involved in the leukemic clone, we purified the eosinophils from a woman heterozygous for the common electrophoretic variants of the G6PD gene. Only type B enzyme was demonstrable in the eosinophils, neutrophils, and red cells, but both A and B enzymes were found in the fibroblasts. The data provide evidence that the eosinophil is involved in the malignant clone. 相似文献