Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Preleukemia”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 541 records · Page 30Linked to original sources
PubMedDate not supplied

In vitro modulation of normal and diseased human neutrophil function by pentoxifylline.

The influence of pentoxifylline on normal and diseased neutrophil function has been studied in vitro. In high concentrations pentoxifylline stimulated human neutrophil chemotaxis toward both bacterial oligopeptides and complement components. Pentoxifylline was also shown in vitro to restore the normal chemotactic capacity of neutrophils from patients with known functional defects, i.e. myelodysplastic syndromes, lazy leucocyte syndrome, juvenile parodontitis, hyper-IgE-syndrome and liver cirrhosis. Pentoxifylline was also shown to strongly inhibit the release of primary and secondary granule release of granulocytes. Moreover, pentoxifylline inhibits both basal and stimulated neutrophil adhesion to both aortic and pulmonary artery calf endothelium. The mechanism whereby pentoxifylline exerts this action is not adequately understood. While our results partially imply interference of pentoxifylline with neutrophil cyclic AMP and/or prostaglandin metabolism, down-regulation of neutrophil functional antigen (e.g. CD11, CD18) expression seems to play a key role in the observed drug effects. Finally, these results indicate that pentoxifylline may be useful in the treatment of granulocyte mediated diseases and symptoms.

Antigens, Differentiation↗
PubMed1982

Cardiomyopathy in a child with hypereosinophilic syndrome.

A 9-year-old boy presented with increasing fatigue, anorexia, weight loss, fever, and absolute eosinophilia (48,000/microL). Pulmonary infiltrates occurred 3 months later. A murmur of mitral regurgitation was heard 5 months after onset of illness, and heart failure soon followed. Despite corticosteroid therapy the eosinophilia persisted intermittently until 1 month before death. The patient died within 9 months of the onset of illness. At necropsy there was cardiomegaly with subendocardial fibrosis in the right and left ventricles. Thrombi were present in the left ventricular apex and behind the posterior mitral leaflet. The findings in 12 previously reported pediatric cases are reviewed. The etiopathogenesis of the hypereosinophilic syndrome is discussed: half of the cases in children are associated with leukemia.

Cardiomyopathies↗
PubMed1993

Transient early metabolic and functional hyperreactivity and late areactivity of lymphocytes in preleukemic AKR mice.

The dynamics of changes in the metabolic and functional activities of thymus, lymph node and spleen lymphocytes and spleen macrophages of AKR mice was examined during the preleukemic period. The MTT colorimetric assay was used to determine the mitochondrial enzyme activity of viable cells, the local xenogeneic GVH reaction and the IL-2 assay for measuring T cell responses, and the IL-1 assay as an indicator of macrophage activity. In the early preleukemic period (at 1.5 months of age), lymphocyte dehydrogenase enzyme hyperactivity was accompanied by a highly increased production of IL-2, positive local xenogeneic GVH reaction and increased IL-1 production. Later on, at the age of 4-5 months, AKR mice demonstrated a progressive decrease in the metabolic activity of lymphocytes, negative local GVH reaction and reduction or lack in IL-2 and IL-1 production. This early hyperreactivity and late, gradually evolving, areactivity of lymphocytes and macrophages was not found in other, non-leukemic strains of mice (RFM, CBA, C57BL).

Animals↗
PubMed1987

The use of the anti-factor VIII method on trephine biopsies of the bone marrow for the identification of immature and atypical megakaryocytes in myeloproliferative diseases and allied disorders. A morphometric study.

A morphometric analysis was performed on trephine biopsies of the bone marrow to identify atypical megakaryocyte proliferation following PAS staining and the immunohistological demonstration of factor VIII. This study includes nine patients with a megakaryoblastic crisis in chronic myeloid leukemia (CML), four with acute megakaryoblastic leukemia (AM) and three with myeloid dysplasia later evolving into overt acute leukemia. Comparison and statistical evaluation of the PAS reaction with anti-factor VIII staining reveals that the latter technique not only facilitates the recognition of immature and abnormal megakaryocytes, but leads to a significantly increased count for all megakaryocytic elements in the bone marrow. Thus our retrospective investigation of routinely processed and paraffin-embedded trephine biopsies shows that the diagnosis of a megakaryoblastic crisis in CML as well as AM may be easily established with the aid of the anti-factor VIII method. In all cases of megakaryoblastic proliferation in CML and AM, the appearance of blasts was associated with moderate to pronounced myelofibrosis which could be also determined by morphometry.

Adult↗
PubMed1994

[Multicentric reticulohistiocytosis and myelodysplastic syndrome].

Multicentric reticulohistiocytosis (MRH) is a rare disorder of skin and joints, and its aetiology is unknown. We describe a male patient who had first developed osteoblastic lesions of the skeleton in 1976 at the age of 59 years. Three years later, he presented with multiple papular and nodular skin lesions, predominantly on the limbs and upper trunk, and 4 years later he developed painful arthropathy. In 1988 skin examination showed multiple brownish-red papulo-nodules, some of which, at mechanically stressed areas, were ulcerated. The patient complained of pronounced arthrotic disorders with reduced joint mobility. Examination of biopsy specimens from active skin lesions demonstrated extensive numbers of macrophages with partial confluence to giant cells with typical ground-glass cytoplasm. Electron microscopy revealed phagocytosis of collagen-like-structures. Examination of bone marrow biopsy specimens revealed diffuse infiltration by histiocytic cells. The diagnosis made was therefore MRH. The patient was treated for several years with different therapeutic regimens, including azathioprin, dapsone, prednisolon, chlorambucil and cyclophosphamide, and complete remission of skin lesions and of bone marrow infiltration was observed. However, a myelodysplastic syndrome with refractory anaemia and ring sideroblasts developed, which is generally understood to be a preleukaemic condition. Myelodysplastic syndromes commonly develop between 3 and 10 years after the start of a therapy with antineoplastic agents.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1996

Progression of a myelodysplastic syndrome to pre-B acute lymphoblastic leukemia: a case report and cell lineage study.

The evolution of acute lymphoblastic leukemia from a myelodysplastic syndrome is a very uncommon event. We describe a 46-year-old man in whom refractory anemia with excess blasts (RAEB) evolved to a pre-B acute lymphocytic leukemia. Trisomy 8 was one of the cytogenetic abnormalities in the dysplastic clone and was detected in both peripheral blood and bone marrow smears of interphase cells by the fluorescence in situ hybridization (FISH) technique. Using a chromosome 8 centromeric specific DNA probe we identified the trisomy 8 to be present in lymphoblasts, erythroid precursors, myeloblasts, promyelocytes, myelocytes, metamyelocytes, granulocytes, and monocytes. Our case supports the hypothesis that in MDS the pluripotent precursor cell is affected, and we examine the potential role of FISH for the study and follow-up of some hematological diseases.

Antigens, Surface↗
PubMedDate not supplied

Ocular complications in myelodysplastic syndromes as preleukemic disorders.

PURPOSE: To identify ocular complications in patients with myelodysplastic syndromes (MDS), who have a propensity to progress to acute myeloid leukemia (AML). METHODS: Forty-one patients with MDS were the subjects in this retrospective study, and 21 patients with AML were selected as controls. Reviewing their clinical records, we verified that corneal ulcer, iridocyclitis, vitreous hemorrhage, retinal hemorrhage, and optic neuritis had been evaluated using slit-lamp assessment and opthalmoscopy in all the patients. In this study, the MDS patients were classified into those with refractory anemia (RA) and those with refractory anemia with excess blasts (RAEB). RESULTS: Ocular complications were found in 19 (46.3%) of the 41 patients with MDS, comprising corneal ulcer (two cases), iridocyclitis (five), vitreous hemorrhage (one), retinal hemorrhage (ten), cotton wool spots (one), and optic neuritis (two). (Some patients had more than one ocular complication.) Ocular complications were identified in 12 of the 21 (57.1%) patients with AML. There was no significant difference in frequency of ocular complications between MDS and AML (P = 0.4892). In MDS, retinal hemorrhage was associated with significantly reduced platelet counts (P = 0.0063). The frequency of ocular complications was significantly higher in MDS-RAEB than in MDS-RA (P = 0.0478). Retinal hemorrhage was significantly more frequent in patients with MDS-RAEB than in patients with MDS-RA (P = 0.0433). CONCLUSION: Ocular complications in MDS patients should be carefully examined as prognostic factors for progression to acute leukemia.

Acute Disease↗
PubMed1982

Bone marrow mast cell content in preleukemic syndrome.

Bone marrow mast cell content was evaluated by a semiquantitative method in 22 marrow specimens from 20 patients with preleukemic syndrome and was compared with 21 marrow specimens from iron-deficient control subjects. Results indicate a statistically significant increase of bone marrow mast cell content in patients with preleukemic syndrome in comparison to control subjects (p less than or equal to 0.0005). Two of 20 preleukemic patients converted to acute myeloblastic leukemia and conversion was accompanied by a significant decrease of bone marrow mast cell content. Our findings indicate that bone marrow mast cell content can be reproducibly quantitated and represents an additional morphologic criterion for diagnosis of the preleukemic syndrome.

Adolescent↗
PubMed1984

Leukemic transformation in hrs mice occurs in an immature-nonactivated thymocyte subpopulation.

The murine leukemic strain HRS/J has an autosomal-recessive, mutant gene, hr, with homozygotes (hr/hr) having a 72% incidence of thymic leukemia at 18 months of age compared to 20% in heterozygotes (hr/+). This study was done to (a) determine if expression of thymocyte differentiation and murine leukemia virus (MuLV) antigens during leukemic transformation were different in hr/hr compared to hr/+ mice, (b) define the subpopulations that were targets for leukemic transformation, and (c) compare the results to reports in other leukemic strains. Flow cytometry analysis of thymus cell suspensions was done with anti-T-cell and anti-H-2 monoclonal antibodies, peanut agglutinin (PNA), and heteroantisera to MuLV antigens. Thymocytes of 1- to 3-month-old HRS/J mice were Thy 1.2+, Lyt 1+2+, H-2Kk-, and MuLV- with an immature-nonactivated phenotype, i.e., PNA+, and Iak-. Preleukemic and leukemic thymocytes showed diversity in expression of Thy 1.2 and Ly antigens with increased H-2Kk and MuLV expression. No differences in phenotype patterns were noted between hr/+ and hr/hr mice during the time course of leukemogenesis. Persistently high PNA/low Iak expression of preleukemic and leukemic thymocytes indicated that the target for HRS leukemic transformation was an immature-nonactivated thymocyte subpopulation in contrast to AKR/J mice in which leukemic transformation involves a mature-activated thymocyte subpopulation. These findings suggest that spontaneously generated leukemogenic viruses in HRS mice have tropism for thymocytes of an immature-nonactivated phenotype.

Animals↗
PubMed1987

Selective activation of endogenous ecotropic retrovirus in hematopoietic tissues of B6C3F1 mice during the preleukemic phase of 1,3-butadiene exposure.

1,3-Butadiene (BD), a comonomer used in the production of synthetic rubber, is a rodent carcinogen. We have observed a marked increase in the incidence of thymic lymphoma in male B6C3F1 relative to NIH Swiss mice chronically exposed to BD in the absence of demonstrable differences in bone marrow (target organ) toxicity. Increased expression of murine leukemia virus (MuLV) antigens was also observed on lymphomas from BD-exposed B6C3F1 mice. Because NIH Swiss mice do not usually express endogenous retroviruses and their ecotropic proviral sequences are not intact, these findings provide presumptive evidence of a role for endogenous retrovirus sequences in BD-induced lymphoma in the B6C3F1 mouse. The present study was conducted to examine the expression and behavior of endogenous retroviruses in these strains during the preleukemic phase of BD exposure. Chronic exposure to BD (1250 ppm) 6 hr/day, 5 days/wk for 3 to 21 weeks increased markedly the quantity of ecotropic retrovirus recoverable from bone marrow, thymus, and spleen of B6C3F1 mice. However, expression of other endogenous retroviruses (xenotropic, MCF-ERV) was not enhanced. No viruses of any type were found in similarly treated NIH Swiss mice. The mechanism of this increase in ecotropic retrovirus in B6C3F1 mice is believed to be de novo activation in greater numbers of cells because changes in the Fv-1 tropism of the replicating viruses or changes in Fv-1 host restriction were not found. Endogenous retroviruses are thus implicated in BD-induced leukemogenesis in B6C3F1 mice. Further studies will examine the role of retrovirus in BD-induced leukemogenesis and the mechanisms of activation of ecotropic proviral sequences in murine cells.

Animals↗
PubMed1990

A new homeobox gene contributes the DNA binding domain of the t(1;19) translocation protein in pre-B ALL.

It was previously shown that the chromosome 19 breakpoint of the t(1;19)(q23;p13.3) translocation, found in human pre-B cell acute lymphoblastic leukemias, is within the E2A transcription factor gene on chromosome 19. A cell line with this translocation contains two novel chimeric mRNAs, both with the same 5'E2A sequences but with different lengths of 3' sequence from a previously unrecognized gene dubbed prl, located on chromosome 1. The chimeric RNAs encode a protein that lacks 171 amino acids of E2A, including its DNA binding and dimerization motifs, but have instead a homeobox-related sequence from prl. Therefore, the production of a chimeric E2A-Prl protein may contribute to the acute lymphoblastic phenotype by directly altering the expression of genes normally responsive to the Prl homeoprotein.

Amino Acid Sequence↗