Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0032463 (polycythemia vera)
 3,374 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The Nd:YAG laser is suitable for the treatment of various otorhinolaryngological clinical disorders. These include the palliative reduction of tumor size in sites with difficult access, treatment of hemangiomas and reduction of hyperplastic turbinates. Within certain limits, other indications are treatment of recurrent epistaxis and recurrent polyposis. Palliative reduction of malignancies in the nasopharynx, esophagus, and bronchial system (laser power density: 1500-8000 W/cm2) must sometimes be carried out in several sessions in order to avoid complications due to the laser (i.e., perforation of the bronchial or esophageal wall, lesions of adjacent vessels or nerves). Nd:YAG laser treatment of hemangiomas (500-3000 W/cm2) can lead to excellent results. To avoid excessive thermal lesions, vascular tissue is cooled with ice cubes or with an ice-cold Ringer's solution. The laser process is continued until the onset of tissue blanching. Carbonizations of the tissue are to be avoided. In Nd:YAG laser therapy of hyperplastic lower nasal conchae (approx. 1000 W/cm2), results are based on submucous scarring in which the covering epithelium is maintained. The objective of Nd:YAG laser treatment of recurrent epistaxis in patients with Osler's disease (500 W/cm2) is to reduce the incidence of hemorrhage. Use of the laser in recurrent polyposis is best confined to patients who refuse conventional surgical revision operations. Laser light (500-3500 W/cm2) should only be applied for a short period of time (0.5 s) to avoid creating a rarefying osteitis.
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PMID:[Use of the Nd:YAG laser in otorhinolaryngology]. 150 Mar 2

Patients with hematologic neoplasias often have chromosomal aberrations in the cells of their bone marrow or unstimulated blood. One recurrent abnormality is a deletion of the long arm of chromosome 20, primarily described in polycythemia vera, but later seen in a range of hematologic disorders. We have studied 32 patients with del(20q) as the sole chromosomal aberration, investigating significance of this aberration for the clinical diagnoses, hematologic parameters, and prognoses within this patient group. According to our results, del(20q) is primarily associated with myeloid disorders, but it is not specific for any certain disease, nor does the proportion of cells with del(20q) correlate with prognosis.
Cancer Genet Cytogenet 1992 Aug
PMID:Clinical significance of the del(20q) chromosome in hematologic disorders. 152 Dec 39

Alkylating agents are known to produce second tumors in cancer patients treated for their primary cancer. Since therapeutic doses are high and the pharmacokinetics of the drugs are thoroughly studied, these agents provide a unique opportunity to compare intrinsic carcinogenic potency between experimental animals and humans. We have examined the carcinogenicity of melphalan, chlorambucil, and cyclophosphamide in causing leukemia in patients treated for cancer or polycythemia vera and lymphosarcoma in rats and mice. A good correlation among species is observed when the carcinogenic potency is based on the total lifetime exposure to active species derived from these drugs.
Cancer Res 1992 May 01
PMID:Carcinogenic potency of alkylating agents in rodents and humans. 156 17

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 51-year-old woman with no history of prior chemotherapy or radiation therapy was diagnosed with essential thrombocythemia (ET) according to the diagnostic criteria established by the Polycythemia Vera Study Group (PVSG). Cytogenetic analysis of bone marrow metaphases revealed both normal female karyotype and a single clonal abnormality, 46,XX,del(5)(q22q35). While chromosomal abnormalities have been reported in ET, their incidence is very low, and no specific abnormality has been found. Many of the reported cases of ET with chromosomal aberrations, including 5q-, do not meet the diagnostic criteria proposed by the PVSG, and may represent one of the other myeloproliferative disorders or a myelodysplastic syndrome. Furthermore, it is important to distinguish the 5q- syndrome, which may present with thrombocytosis and megakaryocytic hyperplasia, from ET. Our patient appears to be the first example of untreated ET clearly meeting the PVSG criteria in which 5q- was the only clonal abnormality seen at diagnosis.
Cancer Genet Cytogenet 1992 Jul 01
PMID:Deletion of the long arm of chromosome 5 in essential thrombocythemia. 833 Feb 75

The aberrant overexpression of interleukin 6 (IL-6) is implicated as an autocrine mechanism in the enhanced proliferation of the neoplastic cell elements in various B- and T-cell malignancies and in some carcinomas and sarcomas; many of these neoplasms have been shown to be associated with a mutated p53 gene. The possibility that wild-type (wt) p53, a nuclear tumor-suppressor protein, but not its transforming mutants might serve to repress IL-6 gene expression was investigated in HeLa cells. We transiently cotransfected these cells with constitutive cytomegalovirus (CMV) enhancer/promoter expression plasmids overproducing wt or mutant human or murine p53 and with appropriate chloramphenicol acetyltransferase (CAT) reporter plasmids containing the promoter elements of human IL-6, c-fos, or beta-actin genes or of porcine major histocompatibility complex (MHC) class I gene in pN-38 to evaluate the effect of the various p53 species on these promoters. Murine and human wt p53 derived from pCMVNc9 and pC53-SN3, respectively, strongly repressed the IL-6 (promoter position -225 to +13), c-fos (-711 to +42), beta-actin (-3400 to +912), and MHC (-528 to -38) promoters in serum-induced HeLa cells; additionally, IL-6 promoter/CAT transcription unit constructs induced by IL-1, phorbol ester, or pseudorabies virus were also repressed by wt human and murine p53. The murine transforming mutant p53 (pCMVc5) was less active in repressing the IL-6, c-fos, beta-actin, and MHC promoter constructs. The human p53 mutant derived from pC53-SCX3 was also less active than the wt protein in repressing the IL-6, c-fos, beta-actin, and MHC promoters, except that serum-induced IL-6/CAT expression was equally repressed by both human wt and mutant p53. In similar transient transfection experiments in HeLa cells, overexpression of the wt human retinoblastoma susceptibility gene product, RB, was found to repress the serum-induced IL-6 (-225 to +13), c-fos (-711 to +42), and beta-actin (-3400 to +912) promoters but not the PRV-induced IL-6 (-110 to +13) or the serum-induced MHC (-528 to -38) promoters. These observations identify transcriptional repression as a property of p53 and suggest that p53 and RB may be involved as transcriptional repressors in modulating IL-6 gene expression during cellular differentiation and oncogenesis.
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PMID:Repression of the interleukin 6 gene promoter by p53 and the retinoblastoma susceptibility gene product. 165 55

Cancer morbidity was investigated in a cohort of 2,170 ethylene oxide (EO)-exposed workers from 2 plants producing disposable medical equipment. The subjects had been employed for at least 1 year during the periods 1970-1985 and 1964-1985, respectively. The exposure to EO was assessed for each of six job categories in the plants with respect to each calendar year, on which basis values for individual cumulative exposure to EO (ppm-years) were calculated. The levels of hydroxyethyl adducts to N-terminal valine (HOEtVal) in hemoglobin fitted well with the values estimated for airborne exposure to EO. No increased cancer incidence was found [standardized morbidity ratio (SMR), 0.78; 95% CI, 0.49-1.21)]. No leukemia was observed, but one case of non-Hodgkin's lymphoma, one case of myeloma, and one case of polycythemia vera were diagnosed as compared with two expected hematopoietic and lymphatic tumors (SMR, 1.54; 95% CI, 0.32-4.5). No stomach cancer was detected as compared with the 0.5 case expected. There were no significant exposure-response associations between estimates of exposure to EO and cancer morbidity.
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PMID:An epidemiological study of cancer risk among workers exposed to ethylene oxide using hemoglobin adducts to validate environmental exposure assessments. 174 69

Erythropoietin is a glycoprotein hormone that plays a vital role in erythropoiesis. It is mainly produced in the fetal liver till the third trimester of pregnancy. At that point, the kidney interstitium takes over this function and becomes the main source of erythropoietin. Hypoxia stimulates erythropoietin production by a mechanism that may require a heme protein as a second messenger. Erythropoietin stimulates the maturation of erythroid precursors (colony-forming unit-erythroid and burst-forming unit-erythroid) via at least two types of cell surface receptors. The higher-affinity receptors appear to be more important in modulating the effects of erythropoietin in vivo. Changes in intracellular calcium may ultimately mediate the action of erythropoietin on erythroid precursors. A specific and sensitive radioimmunoassay is now available for accurately measuring erythropoietin levels. All forms of erythrocytosis except polycythemia vera are associated with elevated erythropoietin levels. Levels are also high in cord blood obtained following fetal asphyxia. Reduced levels are seen in patients with anemia due to renal diseases. The response of erythropoietin to the degree of anemia appears to be attenuated in patients with cancer, chronic diseases, and human immunodeficiency virus (HIV) infection. Erythropoietin has been successfully used for treating patients with anemia due to renal failure. Its use has also been approved for the treatment of anemia patients receiving zidovudine for HIV infection. Encouraging results have been observed when erythropoietin was used to treat anemia due to rheumatoid arthritis, hematological malignancies, and prematurity. It has also been used to increase the yield of autologous blood collected prior to an elective surgical procedure. However, it has not proved to be useful in sickle cell anemia and myelodysplastic syndromes.
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PMID:Erythropoietin. Biology and clinical applications. 178 66

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

We observed significantly reduced serum alpha 2-HS glycoprotein concentrations in patients with acute lymphocytic, acute nonlymphocytic, chronic granulocytic and chronic myelomonocytic leukemias, Hodgkin's and non-Hodgkin's lymphomas, myelofibrosis, and multiple myeloma, but not in patients with chronic lymphocytic leukemia and polycythemia vera, as compared with healthy controls. We followed the serum level of the protein for 18 months. Patients with infectious complications, those receiving cytostatic treatment, and those in the preterminal period had further reduced serum alpha 2-HS glycoprotein levels. The reduction of serum alpha 2-HS glycoprotein concentration was primarily due to decreased production caused by infiltration of the liver, a hepatotoxic effect of cytostatic treatment, and, to a lesser degree, to increased consumption. We found statistically significant negative correlations between serum alpha 2-HS glycoprotein concentration and erythrocyte sedimentation rate, serum aspartate aminotransferase and alkaline phosphatase activities, and IgG and IgM concentrations. The determination of the alpha 2-HS glycoprotein concentration is useful for the assessment and follow-up of the clinical status and therapy of patients with hematological malignancies and also has prognostic significance.
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PMID:Serum alpha 2-HS glycoprotein concentration in patients with hematological malignancies. A follow-up study. 195 51


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