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Biomedical subjects

R Fischer

Publications and source records attributed to R Fischer.

At least 469 records · Page 26Linked to original sources
PubMed1990

Pro-megakaryoblasts in bone marrow tissue from patients with primary (idiopathic) osteo-myelofibrosis (agnogenic myeloid metaplasia). An immunomorphometric study on trephine biopsies.

An immunomorphometric study was performed on bone marrow biopsies from 40 patients with primary osteomyelofibrosis--OMF, (agnogenic myeloid metaplasia) by employment of a monoclonal antibody against glycoprotein IIIa (Y2/51) to determine the number of pro-megakaryoblasts. Specimens from 15 individuals without any hematological disorder served as controls. With reference to the pertinent literature on megakaryocyte precursors and following a pilot study on corresponding smears, in tissue sections pro-megakaryoblasts were characterized by a size of 42.1 +/- 2.6 microns 2 (diameter 7.5 +/- 0.3 microns). In comparison with controls, in OMF no relevant increase in the number of pro-megakaryoblasts per square and cubic millimeter bone marrow was evaluable. The relative frequency of these precursors was significantly reduced due to an increase in the total amount of conspicuously large and abnormal megakaryocytes. Statistical analysis failed to reveal any correlations between counts for pro-megakaryoblasts or the total number of Y2/51--positive megakaryocytic elements with the density of argyrophilic fibers (determined by morphometry) or the platelet values. Our findings imply that in OMF the marked increase in circulating progenitor cells of the megakaryocyte lineage may be generated by extramedullary, probably splenic hematopoiesis. Moreover, the evolution of medullary fibrosis is thought to be associated with the striking predominance of large atypical, possibly overaged and hyperpolyploid megakaryocytes and not with an increase in precursor cells.

Aged↗
PubMed1990

[Multifocal carcinoma of the upper female genital tract: diffuse Müllerian neoplasia].

The simultaneous occurrence of moderately differentiated mesonephroid adenocarcinomas of the endocervix and the ovary and a well differentiated adenocarcinoma of the endometrium in a 46-year-old woman are reported. The problems of classification as multiple primary neoplasma or as metastatic spread are discussed. Histogenesis of multiple primary epithelial malignancies of the female genital tract is explained by the theory of area response of embryologically related organs to an unknown carcinogenic stimulus.

Adenocarcinoma↗
PubMed1990

[Myohyperplasia of the lung arterioles in congenital diaphragmatic defects].

The ratio of lumen/wall thickness of pulmonary arterioles was measured in patients who died post-operatively due to a congenital diaphragmatic defect. This was compared to normal arterioles in healthy newborn lungs. The wall musculature of pulmonary arterioles was 2.8 times thicker than in normal arterioles of newborn lungs. The main cause of this enormous wall thickness is a genuine growth of substance, i.e. myohyperplasia. Myohypertrophia can be an additional reason.

Arteries↗
PubMed1990

An immunomorphometric study on megakaryocyte precursor cells in bone marrow tissue from patients with chronic myeloid leukemia (CML).

An immunomorphometric study was performed on trephine biopsies of the bone marrow in 41 patients with chronic myeloid leukemia (CML) to determine number and size of megakaryocytic precursor cells (pro- and megakaryoblasts). For specific staining, a monoclonal antibody against platelet glycoprotein IIIa (Y2/51) was employed which is applicable on routinely fixed and paraffin embedded tissue. In comparison with control specimens from 15 patients, in CML morphometric analysis revealed an increase in the total amount of megakaryocytes per square and cubic millimeter marrow tissue, but particularly in patients with thrombocythemia. Moreover, a non-disorderly expansion of the megakaryocyte precursor pool was recognizable by showing a relative frequency of pro- and megakaryoblasts in congruence with the normal value. In this context a significant correlation between the counts for Y2/51-positive megakaryocytic elements and promegakaryoblasts with the corresponding platelet values was encountered. The more mature stages of megakaryopoiesis (pro- end megakaryocytes) disclosed a relevant shift to smaller cell forms with rounded cell perimeters and a more compact aspect of their nuclei. Additionally, in 6 patients with CML, evolution into a subacute and manifest (micro)-megakaryoblastic transformation accompanied by myelofibrosis could be demonstrated by a retrospective review of file material.

Antibodies, Monoclonal↗
PubMed1990

Analysis of immunoglobulin, T cell receptor and bcr rearrangements in human malignant lymphoma and Hodgkin's disease.

Rearrangements of immunoglobulin and T cell receptor (TCR) genes have been demonstrated in malignant lymphoid tumors of B and T cell origin. In Philadelphia chromosome-positive chronic myeloid leukemia and acute lymphocytic leukemia cells the bcr and c-abl genes are reorganized and transcripts composed of both genes are expressed. We analyzed the organization of bcr, immunoglobulin and TCR genes in malignant lymphomas. Our data show that in all B cell lymphomas analyzed the JH genes and in some cases also the J kappa genes were rearranged. In a Burkitt lymphoma and in a Kil lymphoma distinct rearranged TCR gamma fragments were detected, in a second Burkitt lymphoma two rearranged TCR beta gene fragments occurred together with a rearranged JH gene fragment. In two T cell lymphomas rearranged TCR beta genes were observed; one of these lymphomas also carried rearranged TCR gamma and JH genes. In Hodgkin's disease in 3 out of 7 cases rearranged immunoglobulin genes were detected. In 1 case, which was diagnosed as a follicular hyperplasia, rearranged JH and TCR gamma fragments appeared. In none of the analyzed lymphomas could bcr rearrangements be observed.

Gene Rearrangement↗
PubMed1990

Bioavailability of iron and cyanide from 59Fe- and 14C-labelled hexacyanoferrates(II) in rats.

"Soluble" (KFe(III)[Fe(II)(CN)6]) and "insoluble Prussian blue" (Fe(III)4[Fe(II)(CN)6]3 labelled with 59Fe either in the ferric (Fe(III)) or ferro (Fe(II)) position and 14C in the cyanide group were synthesized and administered intraperitoneally or orally to adult female rats with normal body iron stores. Following i.p. injection of KFe[Fe(CN)6], the colloidal complex is disintegrated into ferric iron and hexacyanoferrate(II) anion almost completely. About 96% of the ferric iron was retained in the body. Nearly 90% of both ferrous iron and cyanide were excreted with the urine within 7 days after i.p. injection, indicating that most of the undissociated hexacyanoferrate(II) anion ([Fe(CN)6]4-) was excreted through the kidney. Only 9% of the ferrous iron from [Fe(CN)6]4- was found mainly in carcass, liver and gut. As the 59Fe/14C-ratios in organs were found close to 1.0, the dissociation of the hexacyanoferrate(II) anion can only be small in vivo. No detectable 14CO2-activity (less than 0.01%) was monitored in the breath of rats after i.p. injection of the 14C-labelled KFe[Fe(CN)6], also indicating that no significant amounts of cyanide were released after parenteral administration. After oral administration of the soluble and insoluble Prussian blue, 0.3-0.7% of the ferric iron was absorbed and retained mainly in carcass, liver and blood. Only 0.06-0.18% of the ferrous iron was absorbed and mostly excreted with the urine (0.05-0.15%), so that only 0.01-0.03% of the oral ferrous 59Fe was retained in the body after 7-10 days. Very small fractions of 14C-label from the 14CN-group of the soluble and insoluble hexacyanoferrate(II) were observed in the exhaled air (0.04-0.08% of the oral dose). From the 14CO2-exhalation, the 14C-urine excretion and the distribution of iron in blood and organs it can be concluded that the hexacyanoferrate(II) moiety disintegrated only to a small extent in the intestinal tract after oral administration. From a dose of 36 mg hexacyanoferrate(II)/kg, an amount of free (non-complex bound) cyanide can be calculated which is in maximum two orders of magnitude below the LD100-level. Thus, the very low bioavailability of iron and cyanide from hexacyanoferrate(II) compounds after oral application is demonstrated in rats. In the case of a severe nuclear accident, appropriate doses of "soluble" and "insoluble" Prussian blue can be used as safe and effective antidote against radiocaesium contamination.

Animals↗
PubMed1990

[Fine structure of megakaryocyte precursor cells (promegakaryoblasts) derived from smears and sections of bone marrow tissue in patients with chronic myeloid leukemia and so-called primary osteomyelofibrosis with accompanying thrombocythemia].

An immunomorphometric study (antiglycoprotein III a - Y2/51) was performed on routinely processed trephine biopsies in 24 patients with chronic myeloid leukemia (CML) as well as so-called primary osteomyelofibrosis (OMF) to determine the frequency and fine structure of promegakaryoblasts (PMB). With respect to controls, there was a significant increase in megakaryocytes in both entities with an orderly expansion of the precursor subpopulation in CML, but a relative decrease in OMF. In comparison with smears of aspirates, sizes of PMB were reduced by about 25% (factor 1.4) in the corresponding bone marrow sections.

Bone Marrow↗
PubMed1990

[Cooperation between the pathologist and surgeon in modern cancer surgery].

Management of up-to-date cancer therapy in strict accordance with histology and stage warrants more than ever a competent co-operation of the pathologist. For this reason the surgical pathologist has to act in dual roles as a diagnostician and consultant. With reference to the internationally acknowledged histological grading and classification of malignant tumors and further the refined principles of the TNM-classification, diagnostic requirements for surgical pathology have considerably been extended in the field of interdisciplinary oncology.

Biopsy↗
PubMed1990

Megakaryocyte precursors (promegakaryoblasts and megakaryoblasts) in the normal human bone marrow. An immunohistochemical and morphometric study on routinely processed trephine biopsies.

On routinely processed trephine biopsies of the normal human bone marrow derived from 15 patients, immunostaining with a monoclonal antibody against platelet glycoprotein IIIa (Y2/51) and morphometric measurements were performed for the determination of megakaryocyte precursor cells. Based on cell sizes and on comparison with (1) specimens stained by the periodic acid-Schiff reaction and (2) smears, the smallest elements clearly identifiable as belonging to the megakaryocyte series were classified as promegakaryoblasts. Promegakaryoblasts had a frequency of 1.7/sq mm and 140/cu mm of bone marrow and constituted about 8% of the total positively stained megakaryocytic elements; they were characterized by a size of 41.5 sq microns, a diameter of 7.7 microns, a high nuclear-cytoplasmic ratio (0.32) and a nearly circular outline of their nuclear and cellular perimeters.

Adult↗
PubMed1990

[CT follow-up studies of conservatively treated lumbar intervertebral disk herniation].

A CT study was carried out on 43 patients with low back pain and sciatica who were treated conservatively. They were followed up for over 20 months (mean) clinically and monitored by CT before and after treatment. Initially, 38 of them had herniation and 5 had protrusion of the disc. At the time of follow-up only 24 of the initial 40 patients still had neurological deficits. In 76.7% of the patients CT showed an improvement (clear regression in 15 patients, moderate decrease in 18 patients). A favourable tendency towards regression was observed in disc herniation at the L5-S1 level and in cases showing sequestration. The prognosis was unfavourable in herniations at higher levels than L5-S1 and in lateral herniation reaching the intervertebral foramen.

Female↗
PubMed1990

[Etiology of alveolitis and its therapy with indomethacin].

The local antiphlogistic therapy of alveolitis was founded from the importance of inflammation in the etiology. Indomethacin (3% age oily solution) was analysed on their effectiveness. In the control group was treated with chlorphenol-camphor-menthol-solution (ChKM) with addition of procain substance on the gauze strip. Indomethacin is significantly more active with regard to effectiveness, decrease of pain intensity and achievement of painlessness. The local therapy of alveolitis, is free of risk with solution out of Metindol--vials under dosage up to 6 milligram indomethacin substance.

Adult↗
PubMed1990

Histo- and immunomorphometry of megakaryopoiesis in chronic myeloid leukemia with myelofibrosis and so-called primary (idiopathic) osteo-myelofibrosis/-sclerosis.

A morphometric study was performed on trephine biopsies of bone marrow in patients with chronic myeloid leukemia (CML) accompanied by myelofibrosis and in so-called primary (idiopathic) osteomyelofibrosis/-sclerosis (OMF) to evaluate distinctive features of megakaryopoiesis. The periodic acid Schiff reaction (PAS) and a monoclonal antibody against glycoprotein IIIa were employed for the identification of megakaryocytes including precursor cells and Gomori's silver impregnation to determine the density of argyrophilic fibers. All patients with CML revealed a slight to moderate degree of medullary fibrosis and were compared with early hyperplastic stages of OMF showing an identical fiber count. Statistical analysis disclosed that distinctive features existed between these two subgroups. Amongst these variables were sizes of megakaryocytes and corresponding nuclei, frequency of bare nuclei, emperipolesis and numbers of isolated nuclear fragments as well as the circular deviation of cell and nuclear perimeters. Immunomorphometry also included immature elements (pro- and megakaryoblasts) of the megakaryocyte series. Consequently higher cell counts were calculable in both groups combined with smaller sizes and a more rounded aspect of nuclei. However, following immunostaining, significant differences in several megakaryocytic parameters (frequency, size, shape of nuclei) were still demonstrable between CML and OMF cases.

Adult↗
PubMed1990

[Ptosis as the leading symptom of Kearns-Sayre syndrome. A case report for differential diagnosis of external ophthalmoplegia].

Progressive external ophthalmoplegia has generally been considered a brainstem syndrome, but new investigative techniques have identified a variety of etiologies. We report a 17-year-old girl in whom Kearns-Sayre syndrome presented as unilateral ptosis with progression to bilateral ptosis, and discuss the clinical, biochemical, electrophysiological, histopathological and computerized tomographical findings.

Adolescent↗
PubMed1990

A histomorphometric analysis of trephine biopsies of bone marrow from 65 patients with chronic myeloid leukemia. Classification of patients into subgroups with different survival patterns.

A histomorphometric (planimetric) study was performed on trephine biopsies of the bone marrow taken at presentation from 65 patients (31 males and 34 females, with a median age of 48 years) with chronic myeloid leukemia (CML). Specimens from 20 patients (9 males and 11 females, with a median age of 53 years) without any hematologic disorders served as controls. Of the various histologic variables tested, only the counts of neutrophilic granulocytes per 1 sq mm, the ratio of granulocytopoiesis to megakaryopoiesis and the density of reticulin (argyrophilic) fibers revealed a significant correlation with the prognosis. The CML patients were separated into two groups with different survival patterns. Group I (34 patients with a median survival of 24 months) mostly contained cases with the so-called "megakaryocytic subtype" of CML, which is accompanied by variable degrees of fibrosis; group II (31 patients with a median survival of 36 months) mainly contained cases with the "granulocytic subtype," which is not accompanied by myelofibrosis. Among the morphometric parameters, a positive correlation existed between the megakaryocyte count and the reticulin fiber density, which underlines the important role of that cell lineage in fibrillogenesis. There were multiple interrelationships between the histomorphometric variables and the laboratory data. Consequently, multivariate regression methods (using Cox's proportional hazards model) were applied to assess the relative predictive value of the patient characteristics for survival. The derived prognostic model divided the patients into two risk groups, with median survivals of 14 and 41 months, respectively. In order of their entry into the regression model, these variables were percentage of neutrophils in the differential blood count, amount of granulopoiesis, liver size, percentage of peripheral myeloblasts and density of reticulin fibers in the bone marrow. In comparing the two patient groups, based on bone marrow histomorphometric parameters, this model revealed that two of those factors (amount of granulopoiesis and density of reticulin fibers) had a significant correlation with the prognosis.

Biopsy↗
PubMed1990

[BCG osteitis. A case report].

Report of a 8 month old girl with a BCG-Ostitis in the head of the left humerus. The diagnosis was ascertained by typical radiological, histological and immun-histochemical changes. Tuberculostatic therapy resulted in healing. The value of the BCG-vaccination remains beyond all question.

Antitubercular Agents↗