Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Although the term thymic hyperplasia is used most commonly to indicate the occurrence of germinal centers in the thymus, cognizance must be taken of the fact that such centers may occur in apparently normal thymuses in both children and adults. A concept of thymic compartmentalization is proposed with origin of germinal centers in the perivascular space (extraparenchymal compartment) of the thymus. These germinal centers contain a high percentage of B lymphocytes in contrast to the true thymic parenchyma. Although the significance of germinal centers in the thymus parenchyma. Although the significance of germinal centers in the thymus in myasthenia gravis remains controversial, removal of nonneoplastic thymus in this condition is of proven therapeutic value. A variety of neoplasms originating in the thymus have previously been lumped together under the single term "thymoma." It is apparent, however, that thymoma, thymic carcinoid, various lymphomas, and germ cell tumors that arise in the thymus differ not only pathologically but also in their clinical behavior. Thymoma is regarded as an epithelial neoplasm and ultrastucturally is characterized by many desmosomes and tonofilaments. The lymphocytes do not behave in a malignant manner, and lymphomas of the thymus should be sharply separated from true thymoma. Poorly differentiated thymic carcinoma and histiocytic lymphoma may be distinguishable only by the electron microscopic demonstration of desmosomes and filaments in the thymic carcinoma. The evidence that Hodgkin's disease of the thymus ("granulomatous thymoma") is not a variant of thymoma appears overwhelming. Lymphoblastic lymphoma of the thymus is a distinctive neoplasm that is especially prevalent in teenage males. High levels of terminal transferase characterize the lymphoblasts and there is a striking tendency for leukemia to occur. Thymic carcinoid is usually nonfunctional, although one-third of the reported cases are associated with Cushing's syndrome. On light microscopy a ribbon pattern and punctate necroses are characteristic of thymic carcinoids. Electron microscopic demonstration of many dense core granules is invaluable in establishing this diagnosis. An important clue to the diagnosis of thymic seminoma (a neoplasm that shows the same radiosensitivity as its testicular counterpart) is the frequent presence of epithelioid and giant cell granulomas and germinal centers. Separation of the various thymic neoplasms described not only is justifiable on pathologic grounds but is often essential for appropriate patient investigation and treatment.
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PMID:Thymic hyperplasia and neoplasia: a review of current concepts. 36 41

The presence of extrathymic malignancies was investigated in 296 thymectomised myasthenia gravis (MG) cases. In 5 of the 296 cases, extrathymic malignant tumours were observed. 4 of the 5 cases had thymomatous MG. 3 cases had malignant fibrous histiocytoma. Extrathymic malignancies were observed more frequently in thymomatous MG than in non-thymomatous MG. 59 cases (60 tumours), including our 5 cases, who had MG and extrathymic malignant tumours were compiled from the literature. In the 60 extrathymic malignancies, leukaemia and reticulo-endothelial sarcoma were the most frequent types.
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PMID:Extrathymic malignancy in patients with myasthenia gravis. 182 16

The availability of safe and effective preparations of human immune globulin that can be administered intravenously has revolutionized replacement therapy for patients suffering from hypogammaglobulinaemia. Of equal importance and greater interest, however, has been the recognition that super physiological doses of IgG can manipulate an abnormal immune system. Future prospects for the use of immunoglobulin preparations to supply specific antibodies includes the standardization of procedures, whereby patients with acute sepsis may receive antibiotics and immunoglobulin simultaneously. Already there is in vitro evidence that suggests that opsonized bacteria are more readily affected by aminoglycosides. It seems certain that gamma globulin will be used routinely in the management of patients with a number of immunomalignancies, such as chronic lymphatic leukaemia and multiple myeloma that feature hypogammaglobulinaemia, especially when chemotherapy is being administered. Control trials are underway to determine whether gamma globulin given intravenously to premature babies will satisfactorily correct their immuno-deficient state and improve their chances of survival. The immunomanipulative capacity of immunoglobulin is yet to be fully realized. Success in ideopathic thrombocytopenic purpura had led to a trial of gamma globulin in a number of autoimmune conditions. Success has been reported in myasthenia gravis, rheumatoid arthritis, diabetes, patients with circulating antibodies to factor VIII and Kawasaki's disease. The mechanism of action is unknown but almost certainly multifactorial. Two proven mechanisms that will be added to in the future, include blockade of the Fc receptors on cells of the reticulo-endothelial system and manipulation of immunoregulatory T cells by the presence of anti-idiotypic antibodies in the preparation.
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PMID:The clinical use of intravenous gammaglobulin. 244 Jul 43

The thymic epithelium educate the pre-T lymphocytes from bone marrow by either direct contact or humoral stimulation and support their differentiation, proliferation and maturation. Thymic abnormalities include pathological involution, germinal center formation and tumor. Historically, many disorders associated with thymic abnormality have been reported. In this lecture, the structures and functions of human thymus, and immunological and hematological disorders related to thymic abnormalities such as myasthenia gravis, pure red cell aplasia, immunodeficiency syndromes, immunoglobulin dyscrasias, acute T cell-leukemia, Hodgkin disease and lymphocytic lymphoma were reviewed. These extensive reviews suggested "Pharyngeal Pouch Syndrome" and it's significant roles in hematology.
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PMID:[The thymus and blood]. 268 77

There were 72 patients (19 with hepatic failure, 10 with fulminant hepatitis, eight with paraquat poisoning, eight with rheumatoid arthritis, five with myasthenia gravis, four with hyperlipidemia, four with systemic arteriosclerosis including brain infarction, three with pemphigus vulgaris, two with multiple myeloma, two with systemic lupus erythematosus, two cases non-specific Ig-G antibody, two cases medication with an anticancer drug, one with multiple sclerosis, one with Crohn's disease with amyloid kidney and one with chronic myeloblastic leukemia) treated by plasma exchange in the Kidney Center, Tokai University School of Medicine from Jan. 1983 to Dec. 1986. We performed plasma exchange using fresh frozen plasma in 40 cases and Lactate-Ringer's solution containing albumin (4.0-5.0%) in 20 cases as the replacement fluid. In 17 cases, we performed double filtration plasma exchange with the recycle system and no replacement fluid. Although PE therapy did not constitute a basic therapy for hyperlipidemia, pemphigus vulgaris, rheumatoid arthritis, myasthenia gravis, and systemic lupus erythematosus, it was effective in relieving severe clinical symptoms. At the present time, conventional plasma exchange does not improve the survival rate of patients with hepatic failure and fulminant hepatitis. Developments of a new artificial liver support apparatus and identity of many toxic substances in hepatic failure are necessary. No hypotension, hypovolemic shock or other significant complications were experienced.
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PMID:Clinical reports on plasma exchange in the Kidney Center, Tokai University School of Medicine. 344 83

The protein defined by the anti-p19 monoclonal antibody (raised against a 19-kilodalton protein from human T leukemia virus) and normally acquired during the ontogenesis of the human thymic epithelium was studied by indirect immunofluorescence in thymomas and thymic hyperplasias. Hyperplastic (and involuted) thymuses from patients with myasthenia gravis exhibited a clear-cut expression of this differentiation antigen exclusively in epithelial cells, thus qualitatively similar to what was observed in the normal thymus. In thymoma epithelial cells, however, this expression was strongly altered: in the 12 malignant thymomas studied, no anti-p19 reactivity was found. In the four benign cases, a variable number of epithelial cells expressed this antigen. These results suggest that the differentiation antigen of the human thymic epithelium defined by the anti-p19 monoclonal antibody is lost during the malignant transformation occurring in thymomas. Furthermore, this monoclonal antibody provides an additional tool for the study of the degree of dedifferentiation of thymomas.
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PMID:Thymic epithelial antigen, acquired during ontogeny and defined by the anti-p19 monoclonal antibody, is lost in thymomas. 643 6

Deoxyribonucleoside triphosphate (dNTP) concentrations were measured in bone marrow and peripheral blood leucocytes from seven patients with acute Thy-lymphoblastic leukaemia (Thy-ALL), 12 patients with acute myeloblastic leukaemia and 15 patients with acute non-T, non-B lymphoblastic leukaemia (c-ALL), and in thymocytes from patients with myasthenia gravis. Labelled thymidine and deoxycytidine incorporation into DNA was also studied. In Thy-ALL, dNTP concentrations were markedly increased compared with those in the other acute leukaemias. The dNTP concentrations in thymocytes were, however, similar to those in Thy-ALL. 3H-nucleoside incorporation studies showed a marked difference in labelled deoxycytidine incorporation and particularly in the deoxycytidine/thymidine DNA labelling ratio between Thy-ALL and the other cell types. We conclude that the pathways of DNA synthesis in Thy-ALL blasts are different from those in the cells from acute acute leukaemias and some but not all these differences may correspond to differences between normal cortical thymocytes and bone marrow cells.
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PMID:DNA synthesis in thymic-acute lymphoblastic leukaemia. 694 98

Data are presented from 30 cats and 36 dogs in which thymic disease was recognised clinically or on postmortem examination. The diagnoses included thymic lymphoma (19 cats, 12 dogs), thymoma (five cats, 18 dogs), thymic branchial cyst formation or cystic change (one cat, four dogs), thymic hyperplasia (two cats), congenital hypoplasia (one cat, one dog), thymic haemorrhage (one cat, one dog) and thymic amyloidosis (one cat). Thymic lymphoma occurred in younger dogs and cats, and was recorded equally among domestic shorthaired and purebred (especially Siamese) cats. Eight cats with thymic lymphoma were tested for feline leukaemia virus and four were positive. Thymoma occurred more frequently in older cats and dogs, and in Labradors and German shepherd dogs. Thymic tumours were associated with paraneoplastic hypercalcaemia (six dogs), megaoesophagus (two dogs) or interface dermatitis with basement membrane immune complex deposition (one cat). Non-neoplastic thymic diseases were associated with myasthenia gravis (one cat), pemphigus foliaceus (one cat) and superficial necrolytic dermatitis (one cat).
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PMID:Review of thymic pathology in 30 cats and 36 dogs. 932 78

Since Morton and Siegel's epochal experiments 30 years ago animal models have been successfully utilized both for transfer and resolution of autoimmune diseases (AID). More recently human lymphocyte xenografts have reproduced clinical AID in SCID mice. Allogeneic stem cell transplantation demonstrated therapeutic potential in fully developed autoimmune disease. Mixed allogeneic chimerism induced by a sublethal approach has also been shown to prevent and even reverse autoimmune insulitis in nonobese diabetic (NOD) mice. More unexpectedly it was found that experimental adjuvant arthritis (AA) and experimental allergic encephalomyelitis (EAE) could be cured by means of total body irradiation (TBI) followed by autologous hemolymphopoietic stem cell (HSC) transplantation. It was postulated that the newly developing T cells might be tolerant to self antigens. The transfer of AID from affected donors to recipients of allogeneic HSC transplants has been reported for many organ-specific AID, including diabetes (IDDM), thyroiditis, myasthenia gravis and thrombocytopenic purpura (AITP); rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) were not transferred. Conversely patients with the combination of AID and a severe blood disease (leukemia, aplasia) were cured of both diseases following allogeneic BMT, with the notable exception of a relapse in a patient with RA despite full donor engraftment. Allogeneic transplants are certainly more promising as far as concerns a resolution of AID, because they may also exert a graft-versus-autoimmunity effect by gradually eradicating the recipient's lymphopoiesis, but transplant related mortality (TRM) is considered still too high to employ this procedure consistently. New non-myeloablative conditioning regimens, designed to allow the donor's immune system to take over, are already utilized for malignant and non-malignant hematologic diseases, and may become an attractive option for severe, refractory AID. For the time being, however, autologous procedures are still safer, and are being utilized in many projects worldwide. The EBMT/EULAR Registry has collected over 70 patient reports. The more numerous and favorable results have been obtained up to now in multiple scleosis and in systemic lupus erythematosus; the worst in refractory autoimmune thrombocytopenic purpura. No definite conclusions as to the efficacy of autologous HSC transplantation, from marrow or from blood, with or without T-cell depletion, may be drawn at this time, but the feeling is that real cures will be very difficult to obtain by this approach, and that corticosteroid-free remissions and a general lowering of the autoimmune potential will be more realistic goals. Accurate comparisons with already existing aggressive immunosuppressive protocols will become necessary, if possible by means of prospective randomized clinical studies.
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PMID:Stem cell transplantation for severe autoimmune diseases: progress and problems. 979 58

Human T cell leukemia virus type I (HTLV-I) is etiologically associated with adult T cell leukemia (ATL) and chronic neurological disease, tropical spastic paraparesis (TSP). In our study, a unique IL-2 dependent human T cell line, designated TY8-3, was established from a thymoma obtained from a myasthenia gravis patient. The cells were heterogeneous and mainly consisted of those with CD4 , CD8 as well as activation markers and adhesion molecules including IL-2Ralpha,beta,gamma, CD45RO, Tf-R, HLA-DR, LFA-1alpha,beta, LFA-3, ICAM-1 and OX40 but without CD3 surface markers. Furthermore, these cells underwent an efficient and reproducible IL-2 independent transformation upon cocultivation with HTLV-I/II producing cell lines. Interestingly, although the infected cells became IL-2 independent, the growth rate of infected cells was significantly lower than those of parental TY8-3 cells. Clonal HTLV-I proviral DNA and viral particles were detected in the cells. Down-regulation of the lck and fyn genes and activation of the lyn gene was demonstrated in the IL-2 independent HTLV-positive TY8-3 cells. Subclones of TY8-3 cells were again able to be efficiently transformed and became IL-2 independent several months after coculture. Our results thus exhibit that TY8-3 cells and its subclones provide us with a very unique model whereby IL-2 independent transformation events of human T cells by HTLV-I/II in vitro can be studied at a clonal level.
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PMID:IL-2 independent transformation of a unique human T cell line, TY8-3, and its subclones by HTLV-I and -II. 1114 27


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