Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038002 (splenomegaly)
 9,873 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Polycythemia developed in progeny from mothers who were exposed during pregnancy to a combination of methylmercury chloride plus ethylurea and sodium nitrite. The polycythemia occurred as early as one month of age and as many as 24% of the offspring developed the polycythemic condition. Many features of this condition are similar to those of polycythemia vera in man, such as elevated hematocrits and white and red blood cell counts, splenomegaly, and hyperplasia of bone marrow accompanied by megakaryocytosis.
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PMID:Polycythemia produced in rats by environmental contaminants. 47 69

A group of 52 consecutive patients with polycythemia vera was submitted to long-term therapy with radioactive phosphorus (32P). Initial phase of therapy induced complete remissions (normalization of hematogram; spleen not palpable) in 45% of the patients, and partial remissions in the remaining 55%. During maintenance therapy of the complete remission group, mean remission time was about 3.5 years. Individual remission times ranged between 1 and 6 years. In the group of patients with incomplete remission, mean remission time increased with the progression of the disease due to gradual development of "spent" -polycythemia. In patients with splenomegaly, remission time was negatively correlated to spleen size. In both groups the increment of annual accumulated dose averaged 2.4 mCi 32P. When considering polycythemia related causes of death only, mean survival time attained 12 years after initial treatment with 32P. Acute leukemia occurred in 2 patients (4%).
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PMID:32P-therapy in polycythemia vera. 80 69

In mice hypoxic hypoxia (0.5 atm.) results in a severe and persistent thrombocytopenia with a rapid decline in the platelet count between the fifth and ninth days of hypoxia, after which platelet counts level off at about half their normal value. The thrombocytopenia is not due to the associated polycythemia, splenomegaly, or increased blood volume. There is no significant change in platelet counts of mice made polycythemic by daily injections of 6 units of erythropoietin. Fifteen days of hyperbaria (3 atm.) has no effect on the platelet count of otherwise normal mice. Since there is only a slight decline in platelet count during the first 5 days of hypoxia, the persistent thrombocytopenia appears to be due to either a decreased rate of production of platelets or a structural or metabolic defect in platelets produced under conditions of hypoxia.
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PMID:Hypoxia-induced thrombocytopenia in mice. 115 Nov 49

The onset of postpolycythemic myeoloid metaplasia or spent polycythemia has been recognized for many years. As the result of many different series, the development of postpolycythemic myeolid metaplasia might be expected in from 15%-20% of patients with postpolycythemia vera. It appears that an etiologic role for sodium phosphate 32P may exist in this evolutionary pattern. About 70% of patients with PPMM will have symptoms with the onset of the syndrome. The major mechanisms producing symptoms result from (1) anemia, (2) pressure from massive splenomegaly, and (3) bleeding problems. Iron deficiency is a frequent cause of anemia in patients with PPMM. The major mechanism of anemia in these patients, however, relates to ineffective erythropoiesis and shortened red cell survival. Androgen trials for ineffective erythropoiesis seem worthwhile, although data on this point is too limited to draw any firm conclusions. A steroid trial for those patients with major hemolytic episodes is indicated. In those patients in whom adrenal steroid therapy fails to control major hemolysis, a consideration for splenectomy exists. Pressure-related manifestations secondary to massive splenomegaly have been treated with radiation therapy and oral alkylators. Although there is data to document amelioration of painful symptoms with associated shrinking of the spleen, long-term control of this problem has not been forthcoming. Again, patients who are medical failures in control of pressure-related manifestations may be considered for splenectomy. Bleeding problems may arise with PPMM secondary to thrombocytopenia, thrombocythemia, or qualitative platelet dysfunction. Adrenal steroids have met with some success in improving platelet counts in patients with life-threatening thrombocytopenia. Those patients who are medical failures with adrenal steroids in terms of thrombocytopenia might be candidates for splenectomy. Control of thrombocythemia has been observed with oral alkylator therapy and chlorambucil may have a special role in managing this complication. Qualitative platelet defects leading to severe bleeding are best managed with fresh platelet transfusions. Patients with PPMM in contrast to patients with agnogenic myeoloid metaplasia have a more lethal syndrome and shortened survivorship. Causes of death in patients with PPMM include cardiac problems, transition to acute leukemia, hemorrhage, and infection.
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PMID:The evolution into and the treatment of late stage polycythemia vera. 125 Dec 24

We present a case of placental-site trophoblastic tumor associated with erythrocytosis. This 42-year-old woman had persistent amenorrhea and low elevations of her hCG titer after term delivery of a healthy female infant. The woman was noted to have polycythemia of uncertain etiology and was treated with serial phlebotomy. Placental-site trophoblastic tumor was diagnosed and hysterectomy was performed, with subsequent resolution of the polycythemia. Although erythrocytosis has been reported with other gynecologic tumors, this is the first reported association with a placental-site trophoblastic tumor. A role has been suggested for placental lactogen in erythropoiesis during pregnancy based on previous animal studies. Diffuse positive staining for hPL is characteristic of placental-site trophoblastic tumors. We postulate that hPL may have played an ancillary role to erythropoietin in the erythrocytosis demonstrated in this case. Spider angiomata and splenomegaly are interesting clinical features previously described in association with placental-site trophoblastic tumors, and were demonstrated in this patient.
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PMID:Erythrocytosis associated with a placental-site trophoblastic tumor. 131 61

Polycythemia vera (PV) is one of the myeloproliferative diseases, and, as such, is an example of clonal hematopoiesis. The progeny of a single, abnormal, hematopoietic stem cell gain a growth advantage over their normal counterparts resulting in overproduction of red cells generally accompanied by overproduction of granulocytes and platelets as well. There are a variety of nonspecific symptoms at onset related to the increased red cell mass and hematocrit accompanied by the more specific manifestations of pruritus, erythromelalgia, and hepatic, portal, and mesenteric vein thrombosis. Splenomegaly and hypertension are common. The laboratory hallmark is an increased red cell mass. There is also often an increase in white cell count, platelet count, and leukocyte alkaline phosphatase along with other findings reflecting the increased rate of turnover of hematopoietic cells. The bone marrow biopsy generally displays hypercellularity involving all three cell lines and absent iron stores. The diagnosis of PV depends on excluding spurious polycythemia in which there is a high hematocrit but a normal red cell mass and secondary polycythemia in which there is an increased red cell mass in response to tissue hypoxia or the inappropriate production of erythropoietin, generally by a tumor. In addition, one should try to establish the diagnosis in a positive fashion by a combination of studies of the blood and bone marrow. Phlebotomy and occasionally plateletpheresis should be used as acute therapy. Chronic therapy is guided by the knowledge that patients treated with phlebotomy alone have an increased rate of thrombotic complications particularly in older patients and those with previous thrombotic disease. Myelosuppressive therapy can reduce the incidence of these complications, but is commonly associated with an increased incidence of second malignancies, particularly acute leukemia. At present, hydroxyurea is the myelosuppressive agent of choice. Antiplatelet agents have a limited role except in the palliation of the syndrome of erythromelalgia. Median survival is approximately 10 years. As implied above, the causes of morbidity and mortality vary with the mode of chronic therapy which has been employed, leukemia being more common after myelosuppressive therapy and thrombotic complications being more common after therapy with phlebotomy alone. Ten percent to 50% of patients move into a spent phase followed by postpolycythemic myeloid metaplasia, irrespective of previous therapy employed. Eventually, the major problems may be cytopenias and massive splenomegaly.
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PMID:Polycythemia vera. 158 7

A link between hyperparathyroidism and the growth of hematopoietic stem cells is suggested by this report of a parathyroid carcinoma with polycythemia vera. A 56-year-old white woman presented with splenomegaly, a palpable neck mass and hypercalcemia, recurrent six years after resection of a parathyroid tumor. She had pancytosis with a subnormal serum concentration of erythropoietin. Radiographs showed subperiosteal erosions an dosteopenia. Nephrocalcinosis was absent. Bone biopsy showed a decreased cortical width with many intracortical osteoclasts. The cancellous bone area remained normal, but the osteoid area/bone area, osteoblast perimeter and osteoclast perimeter were increased. At surgery, a parathyroid carcinoma was found in the same location operated on previously. As in two other reported cases, postoperative improvement in the hypercalcemia was associated with remission of the blood dyscrasia. A novel finding in this case is that when the hypercalcemia eventually recurred, it was again accompanied by pancytosis. With bisphosphonate therapy, the serum intact parathyroid hormone level increased in response to a decrease in the ionized calcium level, indicating that the cancer was not autonomous. This case suggests that in the presence of the ionized hypercalcemia, the parathyroid tumor may have produced or induced production of a growth factor that can stimulate pancytosis. The differential diagnosis of polycythemia and hypercalcemia should be expanded to include parathyroid tumors in addition to hepatic, adrenal, renal, and ovarian neoplasms.
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PMID:Parathyroid carcinoma associated with polycythemia vera. 179 72

POEMS syndrome is a multisystem disorder associated with polyneuropathy, organomegaly, endocrinopathy, a monoclonal protein (M-protein), and skin changes. The authors describe a patient with POEMS syndrome who has polyneuropathy of the upper and lower extremities, splenomegaly, impotence, IgA-lambda monoclonal protein (M-protein), and marked thickening of his skin. In addition, he has polycythemia vera. Although myeloproliferative disorders have been reported to occur in association with multiple myeloma, they have not been described with POEMS syndrome. The possible etiology of this association is discussed. This patient was successfully treated with melphalan and prednisone at the time of his initial diagnosis, but relapsed 10 years later. The relapse was treated with pulse doses of prednisone alone with complete resolution of his polyneuropathy and skin changes. This was accompanied by a fall in his IgA levels and improvement of his polycythemia.
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PMID:POEMS syndrome associated with polycythemia vera. 253 36

In order to obtain evidence for the essential role of the single base insertion occurring at the 3' end of the env-related gene of Friend spleen focus-forming virus (SFFV) encoding the leukemogenic glycoprotein (gp55) a mutant SFFV genome was constructed in which the segment of the gp55 gene of the polycythemia-inducing strain of SFFV containing the single base insertion and the 6-base-pair duplication was replaced by the corresponding sequence of the Friend murine leukemia virus env gene. The mutant SFFV-Friend murine leukemia virus complex did not induce symptoms of the erythroproliferative disease in adult DBA/2 mice. During passage through newborn DBA/2 mice, the mutant virus complex invariably gave rise to weakly pathogenic variant SFFVs. All of the variant SFFVs induced in adult DBA/2 mice a transient mild splenomegaly associated with normal or slightly low hematocrit value, and they produced gp55 with a molecular weight similar to that of gp55 of the wild-type SFFV. For the two isolates of variant SFFV, the 3' portion of the viral DNA intermediate containing the 3' portion of the gp55 gene was molecularly cloned. Nucleotide sequences of these biologically active cloned DNAs were determined and showed that the variant SFFV genomes arose from the mutant SFFV genome by regaining the single base insertion, indicating that the single base insertion is essential for the biological activity of gp55. Evidence is presented indicating that the single base insertion which causes a loss of the cytoplasmic domain of the env-related protein is not related to the localization of the further-glycosylated form of gp55 in the plasma membrane but is involved with the release of gp55 from cells.
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PMID:Requirement of the single base insertion at the 3' end of the env-related gene of Friend spleen focus-forming virus for pathogenic activity and its effect on localization of the glycoprotein product (gp55). 255 55

The p53 gene is rearranged in a high proportion of erythroleukemic cell lines derived from the spleens of mice infected with Friend leukemia virus. These rearrangements result in either the synthesis of a truncated protein or the inactivation of the p53 gene. Here we have molecularly characterized the rearrangements in two murine erythroleukemic cell lines induced by Friend leukemia virus, DP20-1 and CB3, that contain a rearranged p53 gene and fail to express p53 protein. The rearrangement in the DP20-1 cell line is due to the insertion of Friend spleen focus-forming provirus (SFFV) in the 3' end of the p53 gene in intron sequences between exons 9 and 10. Transfection of molecular clones of this SFFV provirus into NIH3T3 cells results in the generation of infectious virus as determined by its ability, in the presence of helper virus, to induce rapid splenomegaly and polycythemia when injected into adult DBA/2J mice. Insertion of SFFV in DP20-1 cells resulted in the expression of an aberrant 2.9 kb RNA species. Analysis of a molecular clone of the rearranged p53 gene in a second cell line, CB3, revealed that the p53 gene in this clone has sustained a large deletion within the p53 gene resulting in the loss of coding sequences between exons 4 and 8. The 5' end of the deletion originates within exon 4 and extends 3' to within the eighth intron. The significance of these findings with regard to the multi-stage nature of Friend virus induced erythroleukemia is discussed.
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PMID:Inactivation of the p53 oncogene by internal deletion or retroviral integration in erythroleukemic cell lines induced by Friend leukemia virus. 284 14


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