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K Metze

Publications and source records attributed to K Metze.

At least 55 records · Page 3Linked to original sources
PubMed1995

Changes of nucleolar organizer regions in granulopoietic precursors during the course of chronic myeloid leukemia.

The aim of the present study was to analyze the nucleolar organizer region (AgNOR) pattern of granulopoietic precursors in chronic myeloid leukemia (CML) at diagnosis and during the course of the disease. Clusters of AgNORs and isolated dots were counted separately in 24 cases of CML at diagnosis, in 19 cases during the relapse of the chronic phase after treatment, and in 16 cases of blast crisis. For comparison, 20 cases of normal bone marrow were studied. Each cell type had its own characteristic AgNOR pattern, as has been described for normal bone marrow. There was no significant difference in the number of AgNORs between cells in the peripheral blood and bone marrow. Compared with normal granulopoiesis, myeloblasts in CML at diagnosis had lower numbers of clusters, which decreased further during relapse of chronic phase and in blast crisis. Promyelocytes and myelocytes showed significantly fewer dots. The number of AgNOR clusters correlates inversely with the duration of the cell cycle. Therefore, these findings are consistent with the progressive loss in proliferative activity of immature precursors described during the course of CML. As the number of dots indicates cellular maturation, their lower number in promyelocytes and myelocytes in CML favors the concept of a discordant maturation process described in this disease. The separate counting of clusters and dots provides a useful, simple, and cheap method of describing cytokinetic changes during the course of this myeloproliferative disorder.

Cell Differentiation↗
PubMed1994

Effects of simvastatin and pravastatin on endothelium-dependent relaxation in hypercholesterolemic rabbits.

OBJECTIVES: The present study was conducted to investigate endothelium-dependent relaxation in hypercholesterolemic rabbits after treatment with two HMG-CoA reductase inhibitors: Simvastatin and Pravastatin. METHODS: Thirty male New Zealand rabbits were randomly assigned to Control, Simvastatin and Pravastatin groups and fed a diet supplemented with lipids and cholesterol (coconut oil 10% and cholesterol 1%) for 8 weeks. The drugs were administered in dosages of 10 mg/kg from the fourth to seventh weeks; at the end of the seventh week, plasma cholesterol was determined, and the Pravastatin dosage adjusted to 15 mg/kg to obtain similar levels of plasma cholesterol for the two experimental groups. At the end of the 8th week, the animals were killed and aorta removed for histologic examination and the measurement of cholesterol content, as well as for the conduction of endothelium-dependent relaxation studies. RESULTS: At the end of the study serum cholesterol was reduced by 57.1% in the Pravastatin group and 58.4% in the Simvastatin group, with the aortic cholesterol content in the former being significantly lower than that of the Simvastatin and Control groups (p < 0.05). Histologic examination also revealed a significant decrease in volume fractions of foam cells in Pravastatin-treated animals, whereas endothelium-dependent relaxation in response to ACh was significantly impaired in the Simvastatin group. No significant difference was found in relaxation induced by nitroprusside. CONCLUSIONS: In spite of the similar reduction in plasma cholesterol obtained by different doses, it seems that Pravastatin preserves the endothelium-dependent relaxation of aortic rings of hypercholesterolemic rabbits more effectively than does Simvastatin.

Acetylcholine↗
PubMed1994

Pathology of patients with Chagas' disease and acquired immunodeficiency syndrome.

The main pathologic findings in 23 patients with acquired immunodeficiency syndrome (AIDS) and Chagas' disease are reviewed; five are from our own experience and 18 from the literature. The presence of Trypanosoma cruzi parasites and/or T. cruzi antibodies in blood and cerebrospinal fluid was recorded and computerized tomograms of the brain were evaluated. Twenty (87%) of the 23 subjects developed severe, multifocal or diffuse meningoencephalitis with necrosis and hemorrhage associated with numerous tissue parasites. The second most severely affected site was the heart. Seven (30.4%) of the 23 cases had myocarditis on pathologic examination. It was acute in four patients, chronic in two, and simultaneously acute and chronic in one. Acute myocarditis and meningoencephalitis are interpreted as being caused by relapses of chronic T. cruzi infections. An AIDS permissive role is suggested for these conditions since immunologic defense against T. cruzi is mediated mainly by T lymphocytes, whose CD4 subpopulation is depleted in patients with this disease. Consequently, AIDS is a factor that may favor the reactivation of T. cruzi infections. The lesions reported in the association of Chagas' disease with AIDS were compared with those reported from patients without AIDS having fatal, acute, vector-transmitted infections, contaminated blood transfusions, or accidental exposures in the laboratory. For the latter three, meningoencephalitis is uncommon. Only immunosuppressed cases of Chagas' disease have been described as having a pseudotumoral presentation that shows expanding lesions with a mass effect in the cranial cavity that causes intracranial hypertension and simulates neoplasms (tumors such as gliomas, lymphomas, metastases, etc.).

Acquired Immunodeficiency Syndrome↗
PubMed1993

Pattern of nucleolar organizer regions in human leukemic cells.

The pattern of nucleolar organizer regions in bone marrow smears of 40 patients with acute myeloid leukemia (AML), 27 with acute lymphoid leukemia (ALL) and 15 control cases were studied. All normal blasts as well as leukemic blasts revealed at least one cluster of AgNORs. In AML the mean number of clusters (2.87 +/- 0.48) and dots (0.23 +/- 0.17) per cell was significantly lower than in normal myeloblasts (3.27 +/- 0.14 resp. 0.34 +/- 0.12). In ALL the number of clusters (2.82 +/- 0.62) was not significantly different from that of AML blasts. While in all control cases the distribution of the number of clusters per cell within a case could be approximated by a modified Poisson equation, this did not hold for 9 ALL and in 13 AML patients. The histogram of those cases showed a lower dispersion. In ALL, but not in AML, the number of clusters per cell correlated with the peripheral leukocyte count. The present results strengthen the concept that clusters and dots should be regarded as separate entities and suggest that their pattern is related to duration of cell cycle as it has been shown in other tissues.

Adolescent↗
PubMed1991

Atypical stromal giant cells of cervix uteri--evidence of Schwann cell origin.

The report describes atypical multinucleated giant cells adjacent to proliferated nerve fascicles in a circumscribed subepithelial area of the cervix uteri of a 44-year-old multipara. Ultrastructural examination revealed cytoplasmatic processes, basal lamina, intracytoplasmic microfibrils, bizarre nuclear shapes with pseudoinclusions and nuclear fragments connected by small chromatin bridges (nucleotesimals). Immunohistochemical examination showed positive staining for vimentin and S-100 protein. Quantitative topography exhibited an isotropic distribution of the giant cells in an anisotropic architecture of mononuclear cells. A Schwann cell origin of the atypical giant cells is postulated. Aetiopathogenetically the lesion is regarded to be due to a trauma during delivery followed by regenerative proliferation of nerve fascicles and degenerative alterations of proliferating Schwann cells. The knowledge of this lesion is considered important, because the atypical cells could be confounded with malignant neoplastic cells.

Adult↗