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

The expression of the multidrug resistance (MDR) phenotype is connected with the overexpression of P-glycoprotein. By applying the immunocytochemical assay we have demonstrated that in myeloproliferative diseases (AML, ALL, MDS, CGL), in single cases, in smear preparations from the peripheral blood and bone marrow the cells with MDR-positive phenotype can be detected in the material obtained from patients before therapy, and without clinically and anamnestically known exposure to cytotoxic or immunosuppressive drugs. This finding has demonstrated the presence of subpopulations of MDR-positive cells in leukemias and myelodysplastic syndromes already before therapy, and, furthermore, has evidenced that a positive MDR phenotype is not necessarily associated with a malignant phenotype of a malignant cell transformation.
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PMID:[Detection of cells with phenotype of multiple drug resistance in myeloproliferative disorders before the treatment]. 197 May 42

ras gene mutations are the most frequent molecular changes found in the preleukemic syndromes of adults and may play a role in initiating these diseases and in their progression to acute leukemia. However, little is known about the incidence or importance of these genetic mutations in childhood myeloproliferative states (MPS). The bone marrow (BM) monosomy 7 syndrome accounts for a large percentage of childhood MPS. Although the duration of the MPS is quite variable, children with monosomy 7 eventually develop acute myeloid leukemia (AML). We investigated 20 children (13 with MPS, 7 with AML) with BM monosomy 7 or 7q- for the presence of ras gene mutations using the polymerase chain reaction and hybridization with mutation-specific oligonucleotides. Mutations of N-ras and K-ras were detected in three children. Two patients carrying a ras mutation were in the myeloproliferative phase, and one had acute leukemia. All three patients with ras mutations either died of their disease or relapsed after BM transplantation as compared with 8 of 17 without ras mutations. However, this difference is not statistically significant (P = .14, not significant). We conclude that ras mutations are observed in childhood monosomy 7, though less frequently than in adult MDS, and may play a limited role in the progression of this disease to acute leukemia. More patients are needed to address the prognostic role of ras mutations in this rare disease.
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PMID:Mutations of the ras proto-oncogenes in childhood monosomy 7. 199 Nov 70

Electronegative and electropositive filters were compared for the recovery of indigenous bacteriophages from water samples, using the VIRADEL technique. Fiber glass and diatomaceous earth filters displayed low adsorption and recovery, but an important increase of the adsorption percentage was observed when the filters were treated with cationic polymers (about 99% adsorption). A new methodology of virus elution was developed in this study, consisting of the slow passage of the eluent through the filter, thus increasing the contact time between eluent and virus adsorbed on the filters. The use of this technique allows a maximum recovery of 71.2% compared with 46.7% phage recovery obtained by the standard elution procedure. High percentages (over 83%) of phage adsorption were obtained with different filters from 1-liter aliquots of the samples, except for Virosorb 1-MDS filters (between 1.6 and 32% phage adsorption). Phage recovery by using the slow passing of the eluent depended on the filter type, with recovery ranging between 1.6% for Virosorb 1-MDS filters treated with polyethyleneimine and 103.2% for diatomaceous earth filters treated with 0.1% Nalco.
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PMID:Development and application of new positively charged filters for recovery of bacteriophages from water. 205 44

Morphological features of megakaryocytes were studied in 31 patients with myelodysplastic syndrome. Mean nuclear size (N), mean cytoplasmic size (C) and mean N/C ratio were 586 +/- 105 mu 2, 1,391 +/- 327 mu 2 and 0.42 +/- 0.04, respectively. Cell sizes were found to be reduced in 12 patients compared to control subjects. Atypical megakaryocytes were frequently found in patients with RAEB and micromegakaryocytes were also often found in patients with CMML. Mean platelet volume was 0.9 +/- 1.6 fl and the giant platelets were seen in one patient with CMML. In the patients with presence of more than 10% of atypical megakaryocytes, template Ivy bleeding time prolonged and epinephrine- and collagen-induced aggregation decreased. We believe that reduction of megakaryocytes' size and appearance of micromegakryocytes would be helpful in diagnosis of MDS.
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PMID:[Morphological analysis of the megakaryocytes in myelodysplastic syndrome]. 208 33

Erythrocyte basic ferritin (EF) concentration was determined in 64 normal subjects, 123 patients with anemia and 12 patients with leukopenia and thrombocytopenia. There was a significant difference between males and females. Other iron indices, including plasma iron (PI), total iron binding capacity (TIBC), zinc protoporphyrin (ZnPP) and plasma ferritin (PF) were also determined in all the subjects and bone marrow iron stain was determined in the 135 patients. The lowest EF concentration was seen in patients with iron deficiency anemia, being significantly lower than that in normal subjects. EF concentration in patients with iron deficiency erythropoiesis was also lower than that in normal subjects and at the same time significantly different from that in patients with iron deficiency anemia. EF concentration increased prior to PF concentration in patients with iron deficiency anemia who had been treated for a period of 1-8 weeks. EF concentration in patients with anemia of chronic diseases had a significant difference as compared with that in normal subjects and in patients with iron deficiency anemia, but EF concentration in those patients who were accompanied by iron deficiency was similar to that in patients with simple iron deficiency anemia. EF concentration in some iron overloaded patients (aplastic anemia, megaloblastic anemia, MDS etc.) was significantly higher than that in normal subjects. It was demonstrated that there was a good correlation between EF concentration and bone marrow sideroblastic iron in the rank correlation analysis of the iron indices in 135 patients (rs 0.893, P less than 0.01). PF concentration had the best correlation with marrow iron (rs 0.948, P less than 0.01).
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PMID:[Evaluation of erythrocyte basic ferritin in the diagnosis of anemia]. 208

For a better understanding of the karyotype evolution of different marrow cell populations in the course of MDS, 6 patients who eventually developed overt leukemia, belonging to a series of 46 MDS referred to our Institution, were studied ad diagnosis and at leukemic progression. In each case the blast cells were separated from the maturing precursors of the erythroid and granulocytic lineage by centrifugation on a Percoll density gradient. Parallel chromosome investigations were performed in each cell fraction. Cytogenetic analysis performed at presentation did not reveal distinctive karyotype features in metaphases arising in the blast enriched cell fraction, as compared with those obtained from the fraction containing erythroblasts and promyelocytes--myelocytes. These findings suggest that in the initial phase of MDS blast cells may lack distinctive cytogenetic features and may thus represent part of a clonal preleukemic proliferation. At the time of leukemia onset, clonal aberrations [trisomy 21 and del(11)(q23)] showing a restricted pattern of distribution within the blast cell enriched fractions were detected in two patients, whereas one patient showed an increase in size of the abnormal clone carrying monosomy 7, an aberration detected in metaphases obtained from both cell fractions. Thus, some evolutive steps in the natural history of these disorders can be heralded by the acquisition of chromosome aberrations more readily detectable in blast enriched cell fractions. In some cases, partial loss of differentiative capability by the abnormal clone may account for the detection, at leukemia onset, of chromosome aberrations involving both the blast cell fraction and the erythroblast-promyelocyte enriched cell fraction.
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PMID:Chromosome studies of enriched blast cell fractions in myelodysplastic syndromes terminating in acute myeloid leukemia. 209 92

Eight patients with myelodysplastic syndrome (MDS; RA = 1, RAEB = 2, RAEB-t = 4, CMML = 1) received three cycles of recombinant gamma-IFN administered in 2-week intervals, each consisting of a 14-day period of subcutaneous injections at a daily dose of 0.1 mg/m2. Neither a complete nor a partial remission could be obtained. There was only one definite improvement consisting in a rise of hemoglobin level from 7 to more than 12 g/dl. Two minor improvements were due to a slight rise of platelet counts. Three patients developed acute leukemia under treatment with gamma-IFN. Our data suggest that gamma-IFN administered according to the treatment schedule as used in our trial has only a minimal beneficial effect in patients with MDS.
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PMID:Gamma-interferon in myelodysplastic syndromes: a pilot study. 211 96

We studied granulocyte-macrophage (GM) colony formation in chronic myelomonocytic leukemia (CMML, 6 cases), as compared with that in myelodysplastic syndromes (MDS, 6 cases) and myeloproliferative disorders (MPD, 12 cases). GM colony formation of bone marrow cells by colony-stimulating factor (CSF) was normal in CMML and MPD patients, but was decreased in MDS patients. Circulating granulocyte-macrophage progenitors (CFU-GM) were detected in CMML and MPD patients, but not in MDS patients. GM colony formation without CSF was observed in CMML patients, but not in MDS or MPD patients. These endogenous colonies decreased markedly after adherent cell (AdC) depletion, but AdC did not form endogenous colonies in sufficient numbers to explain their marked decrease after AdC depletion. In CMML patients, the numbers of circulating CFU-GM and endogenous colonies correlated with leukocyte and monocyte counts, respectively. The cellular composition of GM colonies was normal in MDS and MPD patients, whereas granulocytic colonies predominated in all CMML patients but one. The CSF-producing capacity of peripheral blood cells was also studied and was found to be increased in CMML patients. This capacity was markedly decreased by AdC depletion; and AdC could produce CSF only in CMML patients. CSF produced by CMML patients supported granulocytic colonies to a greater extent than CSF produced by MDS or MPD patients. These results suggest that enhanced granulopoiesis in CMML patients is closely associated with the possible hyperproduction of granulocytic CSF by their adherent monocytes.
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PMID:Characteristics of granulocyte-macrophage colony formation in chronic myelomonocytic leukemia: a comparative study with other myelodysplastic and myeloproliferative disorders. 211 95

G banding chromosome analysis of bone marrow cells from 51 cases of MDS, including 34 cases of RA, 4 cases of RAS, and 13 cases of RAEB, was carried out using a short term culture method. The morphological abnormalities of dyspoiesis of 46 patients were studied and correlated with chromosomal changes. The results were as follows: Forty-nine percent of the cases had abnormal karyotypes. The frequency of clonal abnormalities was 36.8 percent in RA and RAS, and 84.6 percent in BAEB. The most important aberrations were +8 in 7, HSR in 2, and "spontaneous" PCC in 6 cases. The latter 2 abnormalities had rarely been reported in the literature. Other findings included 1p+, dup (1) (q25q44), -2, 4p+, -5, 5q-, +8p, -12, 12p+, 12q-, -14, 14q+, t (1; 14), -15, +/-16, +/-17, -18, +19, +20, 20q-, +/-21, +/-22, -X, -Y, +Mar, etc. The study also showed a close relation between chromosome aberrations and dyspoiesis. +8 patients tended to have a high percentage of micronuclei in their erythroblasts, and their dyspoiesis usually involved three cell lineages. Patients with PCC were found to have more polyploid metaphases (in cytogenetic studies) and more multinuclear cells (in bone marrow aspirate slides). The results of our study revealed that the more severe dyspoiesis is, the higher the frequency of chromosome aberrations. We consider chromosome abnormalities to play an important role in the pathogenesis of MDS, with cell fusion being involved as well.
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PMID:[Studies on chromosome aberrations and dyshemopoiesis in myelodysplastic syndromes]. 215 90

We report here a rare transformation from refractory anemia with ring sideroblasts (RARS) to chronic myelomonocytic leukemia (CMML). A rare karyotype, inv (12), was also seen at the phase of CMML. A 76-year-old female consulted a physician because of hoarseness in June, 1983. An anemia was found and blood transfusions were made. In August, 1983, she was referred and admitted to Tsukuba University Hospital for a further examination of anemia. A diagnosis of MDS (RARS) was made by hematological examinations, and pyridoxamine was administered from September, 1983. The monocyte counts in the peripheral blood increased above 1,000/microliters continuously from June, 1985, and an exacerbation of anemia was also seen. At the second admission to our hospital in August, 1988, the diagnostic criteria for CMML by the FAB co-operative group was fulfilled. At that time, chromosomal analysis revealed an abnormal karyotype; 46XY, inv (12) (p13.3 q15). Even at the phase of CMML, ringed sideroblasts were also seen in 2.2% of nucleated cell count in the bone marrow. To our knowledge, only 12 cases have been reported as transformation from another type of MDS to CMML. The present case is thought to be a rare case of transformation of MDS. On the other hand, 8 cases with inv (12) associated with malignant hematological disorders have been reported previously. Four of the above 8 cases were MDS. A relationship between development of MDS and inv (12) was suggested.
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PMID:[Chronic myelomonocytic leukemia transformed from refractory anemia with ring sideroblasts with a rare abnormal chromosome, inv (12)]. 217 2


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