Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0026986 (myelodysplastic syndrome)
 14,926 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

23 patients with myelodysplastic syndromes (MDS) and 8 normal controls were analyzed for dysmegakaryopoiesis (DMP) in the bone marrow by alkaline phosphatase anti-alkaline phosphatase (APAAP) technique and by conventional May-Giemsa staining. In the immunocytochemical study, monoclonal antibody (MoAb) against glycoprotein (GP) IIb/IIIa was utilized to demonstrate megakaryocytic cells. 91% (21/23) of MDS cases were detected as having DMP by APAAP method, while only 52% (12/23) were detectable by Giemsa stain. There were difficulties in recognizing small micromegakaryocytes (micro MKs), designated as type 1 atypical MKs, by Giemsa staining. Furthermore, megakaryoblasts (MKBs) were detectable only by APAAP technique. In 8 normal controls, no type 1 and type 3 atypical MKs (round shaped multinuclear MKs) were observed either by Giemsa staining or by the APAAP method, suggesting that they are a distinctive feature of MDS. These results indicate the necessity of immunocytochemical technique for accurate recognition of DMP in MDS.
 ...
PMID:Comparative study of immunocytochemical staining versus Giemsa stain for detecting dysmegakaryopoiesis in myelodysplastic syndromes (MDS) 231 99

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a 23-kDa glycoprotein with remarkably diverse effects on immune and nonimmune cells. GM-CSF induces differentiation of granulocyte, macrophage, and eosinophil precursor cells. Proliferation of monocyte-macrophages, T lymphocytes, keratinocytes, and endothelial cells is also stimulated by GM-CSF. In addition, GM-CSF alters the functional properties of mature granulocytes, macrophages, eosinophils, and basophils. GM-CSF is produced by T lymphocytes, macrophages, and several cell types in extramedullary sites, where it may act in a paracrine manner to regulate the local response to antigenic challenge. Clinical trials of GM-CSF have been conducted in patients with AIDS, aplastic anemia, myelodysplastic syndromes, and sarcoma and following bone marrow transplantation and accidental radiation exposure. GM-CSF significantly increased circulating numbers of several myeloid cells and produced dose-dependent toxicity consisting primarily of myalgias, fever, fluid retention, and serosal effusions. Additional studies are needed to define the role of GM-CSF in treatment of patients with qualitative and quantitative dysfunction of immune cells.
 ...
PMID:Granulocyte-macrophage colony-stimulating factor: pleiotropic cytokine with potential clinical usefulness. 240 68

Five glycoprotein growth factors capable of stimulating the proliferation and differentiation of haemopoietic progenitor cells in vitro have been identified and sequenced over the past ten years. Recombinant DNA technology has recently enabled the production of sufficient amounts of these agents for preclinical testing. Erythropoietin (EPO), granulocyte-macrophage colony-stimulating factor (GM-CSF), and granulocyte colony-stimulating factor (G-CSF) have already entered clinical studies in humans. Interleukin-3 (IL-3) and macrophage colony-stimulating factor (M-CSF) should soon be available for use in humans. EPO corrects the anaemia of end stage renal failure, improving the quality of life for such patients and preventing the need for red cell transfusions. At high dose it increases platelet production in vitro and in vivo and may be of value in humans to prevent the thrombocytopaenia associated with chemotherapy. G-CSF and GM-CSF have been used in several clinical studies. Administration of both growth factors results in a leucocytosis, G-CSF predominantly increasing neutrophil production and GM-CSF increasing production of neutrophils, eosinophils and monocytes. The optimal administration of these agents is via continuous intravenous infusion or daily subcutaneous injections at doses of 3-10 micrograms/kg/24 h. GM-CSF has shown promising results in patients with AIDS and the myelodysplastic syndrome and both G-CSF and GM-CSF have reduced the duration of neutropaenia and incidence of infection associated with chemotherapy. These agents may allow an escalation of the dose-intensity of chemotherapy in the future and thereby, hopefully, increase the response rate and survival for patients with a variety of neoplasms. Several other potential roles for these haemopoietic growth factors are discussed.
 ...
PMID:Clinical trials with haemopoietic growth factors. 249 Dec 51

Colony-stimulating factors (CSFs) are a family of regulatory glycoprotein hormones that promote the proliferation and differentiation of hemopoietic progenitor cells and augment the functions of mature effector cells in vitro. The recent cloning of human genes and the availability of sufficient quantities of recombinant purified growth factors have made it possible to evaluate their therapeutic potential in cytopenic states. Initial studies with GM-CSF have demonstrated its ability to increase neutrophil, monocyte, and eosinophil counts in patients with acquired immune deficiency syndrome (AIDS), myelodysplastic syndrome (MDS), and aplastic anemia. Both GM-CSF and G-CSF reduce the duration of neutropenia following chemotherapy and accelerate hematopoietic recovery in patients undergoing intensive chemotherapy and autologous bone marrow transplantation. Studies are now ongoing to determine the optimal dose, route, schedule of administration, and long-term effects. While the appropriate settings for the use of different CSFs remain to be determined, the initial results of clinical trials are of great interest and suggest that hematopoietic growth factors will play an important role in several clinical arenas.
 ...
PMID:Clinical applications of colony-stimulating factors. 268 11

Research in recombinant DNA technology has led to the characterization of colony-stimulating factors (CSFs) as a family of glycoprotein hormones that are thought to regulate blood cell proliferation and differentiation. CSFs also have been studied for their potential use in treating various hematologic, infectious, and neoplastic disorders. Preliminary-results using granulocyte-macrophage colony-stimulating factor to restore leukocyte competence in acquired immune deficiency syndrome and myelodysplastic syndrome patients have been impressive. Toxic effects generally have not been severe. Other hematopoietic factors are receiving scrutiny for their potential clinical applications.
 ...
PMID:Colony-stimulating factors: present status and future applications. 305 7

Granulocyte--colony stimulating factor (G-CSF, filgrastim) is a glycoprotein hormone of the hematopoietin family that primarily influences the proliferation and differentiation of neutrophilic granulocytic precursors. As with all glyco-protein hormones, G-CSF interacts with target cells by binding to specific cell-surface receptors. It stimulates proliferation, differentiation and activation of cells of the neutrophil--granulocyte lineage and has been investigated as therapy for patients with various neutropenic conditions. A major use for recombinant G-CSF therapy will be in ameliorating the neutropenia which follows cytoreductive chemotherapy. The increase in neutrophils produced by this factor render it a useful treatment for conditions such as congenital, acquired and cyclic neutropenias. It may be an effective therapy in myelodysplasia and aplastic anaemia. G-CSF is also useful in accelerating the recovery of transplanted bone marrow in patients with leukaemia, lymphoma and solid tumors. G-CSF is well tolerated. The most frequently reported adverse effect is mild to moderate bone pain.
 ...
PMID:[Biological properties and clinical application of filgrastim (G-CSF)]. 750 84

Epoetin alfa is a recombinant form of erythropoietin, a glycoprotein hormone which stimulates red blood cell production by stimulating the activity of erythroid progenitor cells. This review discusses the use of the drug in the management of anaemia in diseases often associated with advancing age [renal failure, cancer, rheumatoid arthritis (RA) and other chronic diseases, and the myelodysplastic syndromes (MDS)] and in surgical patients. Intravenous and subcutaneous therapy with epoetin alfa raises haematocrit and haemoglobin levels, and reduces transfusion requirements, in anaemic patients with end-stage renal failure undergoing haemodialysis or peritoneal dialysis. The drug is also effective in the correction of anaemia in patients with chronic renal failure not yet requiring dialysis and does not appear to affect renal haemodynamics adversely or to precipitate the onset of end-stage renal failure. Response rates of 32 to 82% with epoetin alfa therapy have been reported in patients with anaemia associated with cancer or cytotoxic chemotherapy. Limited data in patients with anaemia associated with RA show correction of anaemia after epoetin alfa treatment. Response rates to the drug of 0 to 56% have been noted in patients with MDS. Epoetin alfa also reduces anaemia, increases the capacity for autologous blood donation and reduces the need for allogeneic blood transfusion in patients scheduled to undergo surgery. Hypertension occurs in 30 to 35% of patients with end-stage renal failure who receive epoetin alfa, but this can be managed successfully with correction of fluid status and antihypertensive medication where necessary, and is minimised by avoiding rapid increases in haematocrit. Although vascular access thrombosis has not been conclusively linked to therapy with the drug, increased heparinisation may be required when it is administered to patients on haemodialysis. Epoetin alfa does not appear to exert any direct cerebrovascular adverse effects. Thus, epoetin alfa is a well established and effective therapy for the management of anaemia associated with renal failure. It also improves haematocrit and quality of life in patients with anaemia associated with cancer or chemotherapy. Epoetin alfa increases the capacity for blood donation and reduces the decrease in haematocrit seen in patients donating autologous blood prior to surgery. It also reduces, but may not eliminate, the need for allogeneic blood transfusion.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:Epoetin alfa. A review of its clinical efficacy in the management of anaemia associated with renal failure and chronic disease and its use in surgical patients. 757 84

The expression of the multidrug resistance (MDR-1) gene product, P-170 glycoprotein (P-170) was investigated in 26 patients with low-risk (n = 9) or high-risk (n = 17) myelodysplastic syndrome (MDS), using a panel of monoclonal antibodies to P-170 (C219, JSB1, C494, MRK16) and quantitative analysis of MDR-1 mRNA. P-170 membrane staining was demonstrated in bone marrow blast cells of 14/17 HR-MDS and in 2/9 LR-MDS patients (p < 0.01). P-170 expression was associated with the presence of blast cells characterized by an immature or early myeloid phenotype as defined by CD34 expression (p = 0.034), CD13 or CD33 expression (p = 0.0006), or CD13/33 plus terminal deoxynucleotidyl transferase (TdT) double expression (p = 0.04). With double fluorescence analysis, P-170 expression was observed in a subset of CD34+ cells, but not in CD34- cells. P-170 expression was present in 13/15 (86%) patient samples with an abnormal karyotype as compared with 3/10 samples (30%) with a normal karyotype (p < 0.05). Nine of these 15 patients had a loss or a deletion of chromosome 7. Thirteen out of 16 (81%) MDR-1 positive patients developed acute leukemia versus two of ten (20%) MDR-1 negative patients (p = 0.025). It is concluded that MDR-1 expression in MDS is present in cells with an immature phenotype and is frequently observed in patients who have an abnormal karyotype and a high risk of leukemic transformation.
 ...
PMID:High expression of the multidrug resistance P-glycoprotein in high-risk myelodysplasia is associated with immature phenotype. 810 Jun 4

The red-cell mass is continuously adjusted to the optimal size for its function as an oxygen carrier by messages transmitted to the bone marrow from an oxygen sensor in the kidney. These messages are mediated by the hormone erythropoietin. Erythropoietin is a glycoprotein growth factor synthesized by cells adjacent to the proximal renal tubule in response to signals from a renal oxygen-sensing device, probably a heme protein (1). In the bone marrow, erythropoietin binds to and activates specific receptors on the erythroid progenitor cells (2). In the presence of this erythropoietin-receptor complex the progenitor cells continue their predestined development into mature erythrocytes. Erythropoietin was the first hemopoietic growth factor to be molecularly cloned in 1985 (3). Our understanding of the biology and physiology of erythropoietin has been considerably improved with the advent of recombinant human erythropoietin (rHuEpo). During the past 7 years, rHuEpo has undergone extensive testing in clinical trials. It has been approved for treatment of the anemia of chronic renal failure, both in progressive renal failure and endstage renal failure (ESRD). In these instances, the administration of rHuEpo has been used in effect as a substitutive therapy, since patients' erythropoietin levels are very low despite severe anemia, due to the failure of affected kidneys to produce adequate amounts of the hormone. However, the application of rHuEpo has now moved largely from the primitive indication of renal diseases, and the hormone is currently under study in a number of anemic states of different etiologies, even with relatively high serum erythropoietin levels. Among these, some of the best documented indications are the anemia associated with malignancies, either due to neoplastic bone marrow infiltration or to chemotherapy-related myelosuppression, the anemia of myelodysplastic syndromes and AIDS, the anemia of chronic inflammatory diseases, prematurity, and bone marrow transplantation (4). The purpose of this review is to provide a summary of our present knowledge regarding rHuEpo therapy for the anemia of renal failure. We provide some clues for the correct use of rHuEpo in the treatment of the anemia of chronic inflammatory diseases. In addition, we address a series of new issues in the attempt to better understand the relationship between erythropoietin and liver disease.
 ...
PMID:Erythropoietin and the anemia of chronic diseases. 840 91

The ultrastructure of the leukemic cells in transient leukemia (six cases), myelodysplasia (five cases) and acute megakaryoblastic leukemia (one case) in patients with Down syndrome were studied. The cells were identified to be of megakaryocytic lineage by virtue of the expression of platelet glycoprotein GpIIIa, detected by immunogold labelling. In all patients, some of the leukemic cells had ultrastructural features of megakaryocytes, including ectoplasmic protrusions, demarcation membranes, and alpha granules. Differentiation was greatest in the cells of patients with transient leukemia. These studies provide a detailed assessment of the ultrastructural features of the leukemic cells in the megakaryoblastic leukemias of Down syndrome.
 ...
PMID:Ultrastructural studies of the megakaryoblastic leukemias of Down syndrome. 853 3


<< Previous 1 2 3 4 Next >>