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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Der Pathologe 16 (1995), S. 128-138 
    ISSN: 1432-1963
    Keywords: Schlüsselwörter Dreidimensionale Rekonstruktion ; Lichtmikroskopie ; Serienschnitte ; Megakaryozyten ; Primäre Osteomyelofibrose ; Knochenmark ; Key words Three-dimensional reconstruction ; Light microscopy ; Serial sections ; Megakaryocytes ; Primary osteomyelofibrosis ; Bone marrow
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary Computer-based three-dimensional reconstruction of serially cut light microscopic sections is being increasingly used in medical and biological research. Compared with conventional two-dimensional evaluation of histological sections, complex histotopographical relationships and structural details are easy to assess and could be imposingly visualized on the graphics screen. Because of the rapid progress in modern computer hardware, uncomplicated and fast reconstruction systems are available on standard personal computers. Therefore, 3D reconstruction is applicable for a wide range of investigations that warrant 3D exploration. Own results are presented and the principles of 3D reconstruction, as well as the problems and difficulties in this new technique, are discussed. The complex ameboid morphology of megakaryocytes in bone marrow of primary (idiopathic) osteomyelofibrosis is examined with this new method in combination with selective immunohistochemical staining procedures. 3D reconstruction can visualize the complexity of cytoplasmic and nuclear formation impressively. Moreover, the models generated permit exact quantitative measurements of cell morphology. The technique presented is a powerful tool for anatomical-morphological investigations and can furthermore increase our comprehension of complex histomorphological objects.
    Notes: Zusammenfassung Computergestützte dreidimensionale Rekonstruktionsverfahren von lichtmikroskopischen Serienschnitten haben sich in den letzten Jahren in allen Bereichen der medizinisch-biologischen Forschung etablie-ren können. Im Vergleich zur konventionellen zweidimensionalen Schnittbetrachtung lassen sich komplexe histotopographische Beziehungen sowie Strukturcharakteristika besser erfassen und auch eindrucksvoll darstellen. Aufgrund der schnell fortschreitenden Entwicklung im Bereich der Computertechnik sind heutzutage Rekonstruktionssysteme auch auf preisgünstigen Rechnersystemen verfügbar, so daß sich dieser neuen Methode ein zunehmendes Anwendungsgebiet erschließt. Anhand von eigenen Befunden werden die Grundlagen der 3 D-Rekonstruktion besprochen sowie Schwierigkeiten und Probleme dieser neuen Technik diskutiert. In Kombination mit kontrastreichen und selektiven immunhistochemischen Färbungen wird beispielhaft die komplexe amöbenartige Morphologie der Megakaryozyten bei der primären (idiopathischen) Osteomyelofibrose durch lichtmikroskopische Serienschnitte aus dem Knochenmark vorgestellt. Die erzeugten 3 D-Modelle vermitteln einen plastischen Eindruck von der Komplexität der Zell- und Kernstrukturen dieser Zellen und stellen die Basis für exakte quantitative Analysen der Zellmorphologie dar. Die vorgestellte Technik beinhaltet ein ergänzendes Werkzeug für anatomisch-morphologische Analysen und ist in der Lage, entscheidende Erkenntnisse bei der Untersuchung vielschichtiger histomorphologischer Objekte zu liefern.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1432-0827
    Keywords: Bone mineral density ; Dual-energy X-ray absorptiometry ; Reference range ; Exclusion criteria
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract A cross-sectional, population-based study of 238 randomly selected females and 224 males with German ethnic background (aged 20–80 years) was carried out to establish lumbar spine bone mineral density (BMD) values, using dual X-ray absorptiometry (DXA), for a German population. Comparison was made to the reference range provided by the manufacturer of the DXA equipment. No sex difference in peak spine BMD was found in our study (1.091±0.114 g/cm2 for males versus 1.070±0.113 g/cm2 for females, n.s.). Different patterns of bone loss could be detected in both sexes. In premenopausal women there was no significant correlation between age and BMD (y = 1.044 + 0.00047x, r=0.03, P=0.73) whereas reduction of female BMD at the spine was demonstrated in postmenopausal women (y = 1.189−0.0041x, r=-0.28, P=0.01), underscoring the important role of the menopause for later manifestation of spinal osteoporosis in women. In contrast, in males we found no significant change of BMD with aging (y = 1.071−0.0007x, r=-0.08, P=0.25). Employing commonly used exclusion criteria, BMD values of the study subjects were found mostly within the normal range of BMD. The major finding of our study was good concordance between female data of our study population and the reference data provided by the manufacturer. Clinically significant discrepancies between our data and the Hologic reference range for males could be detected. Our data on males (30–39 years of age) were up to 7% lower than those provided by the manufacturer, probably due to differences in sampling procedures.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1432-0584
    Keywords: Key words Chronic myeloproliferative disorders ; Erythroid precursors ; Neutrophil granulopoiesis ; Megakaryocytes ; Macrophages ; Myelofibrosis ; Enzyme-immunohistochemistry ; Morphometry ; Bone marrow biopsy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  The aim of this review is to evaluate morphological characteristics of the different subtypes of chronic myeloproliferative disorders (MPDs) derived by applying immunohistochemical and morphometric techniques to bone marrow biopsies and to combine these results with relevant clinical parameters. In comparison to control specimens, a significant decrease in erythroid precursors is determinable in chronic myeloid leukemia (CML), while this cell lineage is most prominent in polycythemia vera (PV) and moderately to markedly reduced in idiopathic myelofibrosis (IMF). On the other hand, neutrophilic granulopoiesis shows a predominance in CML and a relevant increase in PV, but no conspicuous changes are detectable in essential thrombocythemia (ET). CML is characterized by a prevalent growth of dwarflike micromegakaryocytes, occurring in particular in the so-called megakaryocyte-rich subtypes (about 30%). This finding differs significantly from the pleomorphous aspect, i.e., clusters of small to giant-sized megakaryocytes in PV and the grossly abnormal (dysplastic) appearance of this cell lineage in patients with IMF. Similar cytological abnormalities of megakaryopoiesis consistent with maturation defects are never encountered in ET. The incidence of mature (resident) macrophages (phagocytic reticular cells) is significantly enhanced in IMF in comparison to the other MPDs and controls. Moreover, there is a striking difference in the density of reticulin-collagen fibers, ranging from normal (ET) to extreme values (IMF). In IMF more than 80% of the patients present with some degree of myelofibrosis-osteosclerosis at diagnosis, while the rest show an initial prefibrotic, hypercellular stage. This feature deserves special attention since, when accompanied by thrombocythemia, it may simulate ET. Sequential bone marrow biopsies in patients with IMF disclose that evolution of myelofibrosis is progressive, but occurs at a variable and unpredictable speed. A synoptical approach regarding clinical diagnosis and histological subtyping of MPDs is explicitly recommended and demonstrated by sets of diagnostic criteria. This rationale requires equal consideration of laboratory data and morphology by clinicians to include well-defined subtypes of MPDs into prospective management studies. Furthermore, it may even warrant follow-up studies and repeated bone marrow examinations in initially unclassifiable cases.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1432-0584
    Keywords: CML ; Myelofibrosis ; Dynamics ; Megakaryocytes ; Morphometry ; Interferon ; Busulfan ; Sequential bone marrow biopsies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract To evaluate treatment-related changes of the reticulin stain-measured fibrosis in Ph1+-CML, a clinicopathological study was performed on sequential trephine biopsies of the bone marrow following either interferon (IFN) or busulfan (BU) monotherapy. Using the monoclonal antibody CD61 for the identification of megakaryopoiesis and Gomori's silver impregnation method, number of megakaryocytes and density of argyrophilic (reticulin and collagen) fibers were determined by morphometry. We studied specimens from 26 patients with IFN-alpha 2b (including nine patients with additional IFN gamma) therapy and from 23 patients who had received BU. In both groups, repeated bone marrow biopsies (total 125) revealed a significant increase in the fiber content, as well as in the number of megakaryocytes during treatment. To assess the dynamics of myelofibrosis more precisely, computation of differences in the degree of fiber density between the first and last examination was carried out. Regarding the considerable variations in the biopsy intervals, a so-called myelofibrosis progression index (MPI) was calculated. Following this rationale, we were able to demonstrate that, in comparison to the BU-group, speed of progression of bone marrow fibrosis was significantly increased in CML patients treated with IFN. Preliminary statistical analysis indicated a relationship between myelofibrosis on admission, which was always associated with increased growth of megakaryocytes, and the MPI with survival. Even when these parameters were regarded, prognosis was significantly more favorable in the IFN-treated patients. The failure of IFN and BU to inhibit the evolution of myelofibrosis may be related to several conversely acting pathomechanisms. Among others, the inability of both therapeutic agents to reduce the number of megakaryocytes more effectively should be taken into consideration.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 1432-0584
    Keywords: Key words CML ; Myelofibrosis ; Dynamics ; Megakaryocytes ; Morphometry ; Interferon ; Busulfan ; Sequential bone marrow biopsies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  To evaluate treatment-related changes of the reticulin stain-measured fibrosis in Ph1+-CML, a clinicopathological study was performed on sequential trephine biopsies of the bone marrow following either interferon (IFN) or busulfan (BU) monotherapy. Using the monoclonal antibody CD61 for the identification of megakaryopoiesis and Gomori's silver impregnation method, number of megakaryocytes and density of argyrophilic (reticulin and collagen) fibers were determined by morphometry. We studied specimens from 26 patients with IFN-alpha 2b (including nine patients with additional IFN gamma) therapy and from 23 patients who had received BU. In both groups, repeated bone marrow biopsies (total 125) revealed a significant increase in the fiber content, as well as in the number of megakaryocytes during treatment. To assess the dynamics of myelofibrosis more precisely, computation of differences in the degree of fiber density between the first and last examination was carried out. Regarding the considerable variations in the biopsy intervals, a so-called myelofibrosis progression index (MPI) was calculated. Following this rationale, we were able to demonstrate that, in comparison to the BU-group, speed of progression of bone marrow fibrosis was significantly increased in CML patients treated with IFN. Preliminary statistical analysis indicated a relationship between myelofibrosis on admission, which was always associated with increased growth of megakaryocytes, and the MPI with survival. Even when these parameters were regarded, prognosis was significantly more favorable in the IFN-treated patients. The failure of IFN and BU to inhibit the evolution of myelofibrosis may be related to several conversely acting pathomechanisms. Among others, the inability of both therapeutic agents to reduce the number of megakaryocytes more effectively should be taken into consideration.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 1432-0584
    Keywords: Key words Apoptosis ; PCNA-labeling ; Idiopathic thrombocytopenia ; Polyglobuly ; Reactive thrombocytosis ; Primary thrombocythemia ; Polycythemia vera ; AML ; Hematopoietic turnover index ; Bone marrow
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  In order to determine the dynamics of hematopoietic cell turnover, proliferative activity and incidence of apoptosis (programmed cell death) were evaluated in bone marrow trephine biopsies. Selection of patients (20 in each group) included in addition to a control group, idiopathic thrombocytopenia (ITP), reactive thrombocytosis (TH), secondary polycythemia-smokers' polyglobuly (PG), primary (essential-hemorrhagic) thrombocythemia (PTH), polycythemia vera (PV), and finally acute myeloid leukemia (AML). Apoptosis was demonstrated by the in situ end-labeling technique (ISEL) and proliferative activity by applying the monoclonal antibody PC10 raised against proliferating cell nuclear antigen (PCNA). To assess dynamic features of hematopoiesis, an index was calculated consisting of the ratio between PCNA-positive nuclei and the apoptotic cell fraction. This factor was termed the hematopoietic turnover index (HTI). Morphometric analysis revealed that the HTI was significantly increased in AML and PV. According to cell culture studies both disorders are characterized by either a prevalent proliferation of the myeloid or erythroid cell mass. On the other hand, PG, PTH, and TH showed no relevant enhancement of this index in comparison to the control specimen. In vitro experiment results are in keeping with the finding that PG and PTH are not associated with a significant expansion of the erythroid lineage (CFU-E). Similar to ITP and TH, in PTH megakaryocyte proliferation (CFU-MEG) is the predominant feature of cell turnover. Differences between PTH and TH are in line with the reduced in vitro formation of CFU-MEG in the latter disorder. In conclusion, our in situ study on turnover rates of the bone marrow in various neoplastic and reactive lesions extends previous experimental data on hematopoietic cell kinetics.
    Type of Medium: Electronic Resource
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  • 7
    ISSN: 1432-0584
    Keywords: Key words Idiopathic myelofibrosis ; PCNA labeling ; Apoptosis ; Dynamic disease features ; Prognosis ; Proportion of life loss ; Bone marrow
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  A retrospective study of 120 patients with the clinically and histologically established diagnosis of idiopathic (primary) myelofibrosis (IMF) was performed to determine prognostic factors of predictive value, including parameters characterizing the dynamics of hematopoietic cell kinetics. In contrast to previous studies, our cohort comprised the full spectrum of the disease, from initial prefibrotic to advanced osteosclerotic stages. The in situ end-labeling (ISEL) technique was used to demonstrate apoptosis, in order to determine dynamic parameters of predictive value. Cell proliferation was evaluated by employing the monoclonal antibody PC10 directed against proliferating cell nuclear antigen (PCNA). Proliferative activity (PCNA index) and frequency of apoptosis showed significant differences between early and advanced fibrosclerotic stages of disease. Decrease in proliferation indicated a significantly shorter survival, whereas a higher frequency of apoptotic cells was associated with a better prognosis. It may be speculated that a normal or enhanced proliferation rate expressed by PCNA positivity (late G1- and S-phase of the cell cycle) that is accompanied by a higher incidence of apoptosis reflects the regenerative (turnover) capacity of hematopoiesis. This may apply especially to early hypercellular stages without relevant myelofibrosis. In consideration of a recently published multivariate risk model, a simplified synthesis score for stratification of a patient's prognosis was constructed. Age, degree of anemia, leukocytes, and platelet count were regarded as the most important parameters. A substantial improvement of prognostic efficiency was further achieved by including PCNA index and frequency of apoptosis. Our results are in keeping with the assumption that generalization, indicated by myeloid metaplasia, has a prodigious impact on prognosis in IMF. Furthermore, in this context dynamic features such as proliferative activity and frequency of apoptosis exert an additional predictive value.
    Type of Medium: Electronic Resource
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