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Dive into the research topics where Gertfried Schweikhart is active.

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Featured researches published by Gertfried Schweikhart.


Placenta | 1987

Interpretation of syncytial sprouts and bridges in the human placenta

Steven John Cantle; Peter Kaufmann; Michael Luckhardt; Gertfried Schweikhart

Human placental villi from normal and pathological material from the eighth to the 40th week of gestation were examined by light, scanning and transmission electron microscopy. Trophoblastic specializations--such as syncytial sprouts of early and late pregnancy, syncytial knots and syncytial bridges--were classified into proliferative and degenerative processes or artefacts caused by tangential sectioning. In early pregnancy and in diabetes mellitus most syncytial sprouts represent the initial phases in the development of villi. In late pregnancy, in particular in pre-eclampsia, most syncytial knots, sprouts and bridges are histological artefacts, caused by tangential sectioning of the trophoblastic surface. The chance of producing such artefacts is increased with increasing section thickness and with increasing branching and tortuosity of the villi. However, a small proportion of the syncytial knots, sprouts and bridges in the last-trimester placenta, those containing coarse pyknotic nuclei, are trophoblastic specializations of a probably degenerative character.


Placenta | 1987

Cross-sectional features and three-dimensional structure of human placental Villi

Peter Kaufmann; Michael Luckhardt; Gertfried Schweikhart; Steven John Cantle

Human placental villi from both normal and complicated pregnancies were examined by both light and scanning electron microscopy. The findings provide evidence that histological features such as syncytial sprouts, bridges, and a net-like arrangement of villi represent tangential sections of irregularly shaped villi rather than proliferative activity of the villous surface. Hence the two-dimensional appearance of paraffin and semithin sections has to be interpreted three-dimensionally in comparison with the respective scanning electron micrographs. In the light of these findings the various types of villous maldevelopment are summarized in a diagram which may be used as an aid for pathological diagnosis.


Archives of Gynecology and Obstetrics | 1978

Zur Abgrenzung normaler, artefizieller und pathologischer Strukturen in reifen menschlichen Plazentazotten

Susanne Voigt; Peter Kaufmann; Gertfried Schweikhart

SummaryMorphometrical relations of human placental villi from 14 normal placentas of the 38th to 42nd week of pregnancy terminated by Cesarean section were examined in relation to the method of fixation. Villous tissue was obtained from central areas of the in situ placenta with intact maternal circulation by means of puncture aspiration and punch biopsy. Further punch biopsies were performed 2, 5, 10 and 20 min after manual removal of the placenta. Semithin sections of these villi were photographed and examined morphometrically. The findings demonstrate clear effects on quantitative data as a result of the period of ischemia between manual removal and fixation of tissue. Significant changes of several parameters (mean trophoblastic volume, size of epithelial plates, volume of connective tissue, volume of fetal vessel lumina, etc.) occur as early as 2 min after separation of the placenta from the maternal circulation. They are mostly related to a collapse of intravillous vessels. The villous branches may be classified according to structure and morphometry, if they have been obtained under optimal conditions of fixation and prior to any vascular collapse.ZusammenfassungAn 14 normal funktionsfähigen menschlichen Plazenten der 38.–42. Schwangerschaftswoche — ausschließlich während Sectio caesarea gewonnen — wurden die Proportionen der Zottenendverzweigungen in Abhängigkeit von der Fixationsmethode untersucht. Von den noch in situ belassenen, maternal durchbluteten Plazenten wurde mittels Aspirationspunktion und Biopsiezange Zottengewebe aus zentralen Arealen entnommen. Nach manueller Lösung wurden in Abständen von 2, 5, 10 und 20 min Zangenbiopsien durchgeführt. Semidü nnschnittpräparate dieser Plazentazotten wurden photographiert und morphometrisch ausgewertet. Die Ergebnisse zeigen deutliche Auswirkungen der Ischämiezeit zwischen Lösung und Fixation der Plazenta auf die Zottenproportionen. Signifikante Veränderungen mehrerer Parameter (mittleres Trophoblastvolumen, Ausdehnung der Epithelplatten, Bindegewebsvolumen, fetales Gefäßvolumen u. a.) treten bereits 2 min nach Lösung der Plazenta auf. Sie lassen sich weitgehend auf einen intravillösen Gefäßkollaps zurückfuhren. Bei voll entfalteten Zottengefäßen unter optimalen Fixationsbedingungen können die beschriebenen Zottenendverzweigungen (< 80 μm) in strukturell und morphometrisch unterschiedliche Abschnitte eingeteilt werden.Morphometrical relations of human placental villi from 14 normal placentas of the 38th to 42nd week of pregnancy terminated by Cesarean section were examined in relation to the method of fixation. Villous tissue was obtained from central areas of the in situ placenta with intact maternal circulation by means of puncture aspiration and punch biopsy. Further punch biopsies were performed 2, 5, 10 and 20 min after manual removal of the placenta. Semithin sections of these villi were photographed and examined morphometrically. The findings demonstrate clear effects on quantitative data as a result of the period of ischemia between manual removal and fixation of tissue. Significant changes of several parameters (mean trophoblastic volume, size of epithelial plates, volume of connective tissue, volume of fetal vessel lumina, etc.) occur as early as 2 min after separation of the placenta from the maternal circulation. They are mostly related to a collapse of intravillous vessels. The villous branches may be classified according to structure and morphometry, if they have been obtained under optimal conditions of fixation and prior to any vascular collapse.


Virchows Archiv | 1984

Peanut lectin histochemistry of 120 mammary carcinomas and its relation to tumor type, grading, staging, and receptor status

Werner Böcker; Alexander Klaubert; Jens Bahnsen; Gertfried Schweikhart; Kunibert Pollow; Margarete Mitze; Rolf Kreienberg; Thomas Beck; Hans-E. Stegner

Peanut lectin (PNL) is known to bindβ-d-galactosyl-(1-3)-N-acetyl-d-galactosamine, which provides antigenetic determination of the Thomsen-Friedenreich antigen (TFAg). The aim of this study was to analyse the expression of peanut lectin binding sites in mammary carcinomas and to correlate these with tumor type, histological grading, staging and biochemical receptor status. The series comprised 120 invasive mammary carcinomas and 14 cases with normal breast tissue or benign epithelial proliferations as controls. In controls mainly luminal or apical PNL-binding was discovered, however, in all except three carcinomas a cytoplasmatic localisation of TFAg with three major patterns was found: diffuse, granular-globular and vacuolar reactions. The quantitative-qualitative evaluation of the PNL-staining revealed a statistically significant correlation between globular-vacuolar PNL-reaction and tumor type with a higher percentage of this type of reaction in invasive lobular carcinomas as opposed to tubular and invasive ductal carcinomas. Furthermore a statistically significant relationship was disclosed between PNL-histopositivity and estrogen positive - progesterone positive cases. However, the findings of contradictory PNL-status and hormone-receptor status illustrates clearly the difficulty of predicting the biochemical receptor status. No correlation was found between PNL-histochemistry, histological grading, and pathological staging. The practical implications of PNL-histochemistry of mammary carcinomas are discussed.


Archives of Gynecology and Obstetrics | 1986

Immunohistochemical location of HPL, SP1 and beta-HCG in normal placentas of varying gestational age.

Th. Beck; Gertfried Schweikhart; E. Stolz

SummarySixty-four placentas at various gestational ages were examined by immunohistochemical stains for HPL, SP1 and β-HCG according to a modified PAP method (Sternberger 1970). Syncytiotrophoblast cell layer was identified as the main site of synthesis. Extravillous immunohistochemical reactions for HPL and SP1 (but not for β-HCG) were found in X-cells of the basal plate and in the intervillous trophoblast islands. These cell types would thus seem to be derived from trophoblast. Hofbauer-cells of villous connective tissue stained specifically for β-HCG apparently because of HCG phagocytosis. The intensity of staining for HPL, SP1 and β-HCG was evaluated semiquantitatively in the syncytiotrophoblast cell layer at various gestational weeks. The maximum of staining for β-HCG was found in the uniform syncytiotrophoblast layer of immature intermediate villi in early pregnancy (7–14 weeks), HPL and SP1 had their peak of staining reaction at 32–36 weeks of gestation. Increasing maturation results in a subspecialisation of the villous surface: epithelial plates (allowing feto maternal exchange) and nucleated portions of syncytiotrophoblast (which are the main site of hormone production and endocrine activity).


Pathology Research and Practice | 1985

Imunohistochemical Demonstration of Carcinoembryonic Antigen (CEA) in 120 Mammary Carcinomas and its Correlation with Tumor Type, Grading, Staging Plasma-CEA, and Biochemical Receptor Status

Werner Böcker; Gertfried Schweikhart; Kuniberg Pollow; Rolf Kreienberg; Alexander Klaubert; Sören Schröder; Margarete Mitze; Jens Bahnsen; Hans-E. Stegner

Antisera to CEA were used for the immunohistochemical localization and quantification of this antigen in 120 Bouin-fixed, paraffin embedded mammary carcinomas. These results were compared to tumor type, grading, staging, biochemical receptor status, cytosolic CEA-levels of the same tumors, and preoperative plasma CEA-levels. Mammary carcinomas were usually characterized by a low percentage of CEA-positive tumor cells: 50.9% of the cases contained more than 5% CEA-positive tumor cells and were therefore defined as being CEA-histopositive in this study. A relation could be shown between CEA-histopositivity and the histologic tumor type. The majority of invasive lobular carcinomas, tubular, and cribriform carcinomas was CEA-negative (72%). Conversely, 70% of invasive ductal carcinomas were CEA-positive. There was a significantly higher percentage of CEA-histopositivity in grade III tumors than in grade I/II carcinomas. The results obtained by quantification of the immunohistochemical staining of CEA were positively correlated with the results obtained by cytosolic CEA-assay. The overall concordance between tissue and plasma determinations of CEA was found to be 57.1%. A positive trend could be found between CEA-positivity and staging. However, no correlation was observed between CEA-positivity and estrogen receptor status.


Archives of Gynecology and Obstetrics | 1980

[Problems of distinction of normal, arteficial and pathological structures in mature human placental villi. III. Morphometric studies in rhesus incompatibility (author's transl)].

Inge Pilz; Gertfried Schweikhart; Peter Kaufmann

SummarySections of human placental villi which were up to 80 μm in diameter were examined light microscopically and morphometrically. The villi were obtained by taking an aspiration biopsy of the attached placenta from 20 normal patients at term and from eight patients delivered at or before 37 weeks because of varying degrees of rhesus incompatibility. The distribution of three histological types of villi was determined. The intermediate villi from patients with erythroblastosis showed an increase in number and volume matching the severity of the disease. The intermediate villi also showed an increase in the amount of cytotrophoblasts, in the amount of materno-fetal diffusion surface area, in the thickness of syncytium, and in the number of Hofbauer cells. The terminal villi were not affected by erythroblastosis and the mature end villi showed a relative decrease in number. To obtain these results an optimal fixation technique was required.ZusammenfassungSemidünnschnitte von Plazentazotten bis 80 μm Durchmesser, gewonnen durch in situ-Punktion aus 20 normalen, reifen, menschlichen Plazenten und acht Fällen von Rhesus-Inkompatibilität verschiedener Schweregrade, wurden lichtmikroskopisch und morphometrisch untersucht. Ferner wurden auf Übersichtsbildern die Verteilungsmuster von drei histologisch definierten Zottentypen quantitativ erfaßt. Signifikante Unterschiede der Erythroblastose-Plazenten gegenüber den Normalfällen bestehen in einer Vermehrung des Zytotrophoblasten, der Zunahme der materno-fetalen Diffusionsstrecke und der Synzytiumdicke sowie gehäuften Hofbauerzellen. Schwankungen in den morphometrischen Werten und fehlende quantitative Differenzen bei vielen Parametern, bei denen subjektiv-visuell Veränderungen zu bestehen scheinen, werden darauf zurückgeführt, daß die Endzotten strukturell von dem krankhaften Geschehen nicht betroffen werden, sondern nur ein spezieller Zottentyp, die in sehr wechselnder Zahl vorhandenen Intermediärzotten. Diese zeigen nicht nur die oben beschriebenen Verä nderungen, sondern nehmen auch mit zunehmendem Schweregrad der Erkrankung an Zahl und Volumen zu. Dagegen nimmt die Zahl der ausgereiften Endzotten gleichzeitig ab. Die spezifische morphologische Beurteilung der in der Rhesus-Plazenta wichtigen Parameter — insbesondere die strukturelle Differenzierung verschiedener Zottentypen und ihre Kaliberverteilung — setzt eine optimale Fixationstechnik voraus.


Archiv f�r Gyn�kologie | 1977

Zur Abgrenzung normaler, artefizieller und pathologischer Strukturen in reifen menschlichen Plazentazotten@@@Problems of distinction of normal, arteficial and pathological structures in mature human placental villi: I. Ultrastruktur des Syncytiotrophoblasten@@@I. Ultrastructure of the syncytiotrophoblast

Gertfried Schweikhart; Peter Kaufmann

Thirty-four mature human placentae were punctured in situ during cesarean section and fixed immediately. The ten cases which seemed normal according to clinical and morphological criteria were examined electron-microscopically. Findings won in ideal conditions after perfusion fixation of the guinea-pig placenta were compared to the human punction samples. The granular endoplasmic reticulum in the syncytium proved to be the most susceptable parameter. Its cisternae are narrow and arranged parallel to each other after optimal fixation. The larger the ischemic phase--already detectable after 2 min--, the more disorientated and dilated they become. The mitochondria only react considerably later. Similar structural alterations also occur in the course of pathological processes. The meaning of arteficially and pathologically induced ultrastructural changes and their interdependance are discussed.SummaryThirty-four mature human placentae were punctured in situ during cesarean section and fixed immediately. The ten cases which seemend normal according to clinical and morphological criteria were examined electron-microscopically. Findings won in ideal conditions after perfusion fixation of the guineapig placenta were compared to the human punction samples. The granular endoplasmic reticulum in the syncytium proved to be the most susceptable parameter. Its cisternae are narrow and arranged parallel to each other after optimal fixation. The larger the ischemic phase — already detectable after 2 min —, the more disorientated and dilated they become. The mitochondria only react considerably later. Similar structural alterations also occur in the course of pathological processes. The meaning of arteficially and pathologically induced ultrastructural changes and their interdependance are discussed.ZusammenfassungAus 34 während Schnittentbindungen in situ punktierten und ohne Latenzzeit fixierten reifen menschlichen Plazenten wurden die 10 Fälle elektronenmikroskopisch untersucht, die nach klinischen und morphologischen Kriterien als normal gelten konnten. Befunde, die unter idealen Bedingungen nach Perfusionsfixation der Meerschweinchenplazenta gewonnen wurden, werden mit den menschlichen Punktionsproben verglichen. Dabei erweist sich das rauhe eR des Syncytiums als der empfindlichste Parameter: Seine im Idealfall engen, parallel orientierten Zisternen werden mit zunehmender Ischaemiezeit — erkennbar bereits nach 2 m — desorientiert und dilatiert. Die Mitochondrien reagieren erst wesentlich später. Ähnliche Veränderungen treten auch bei pathologischen Prozessen auf. Die Aussagekraft von artefiziell und pathologisch verursachten ultrastrukturellen Veränderungen und deren gegenseitige Beziehungen werden diskutiert.


Archives of Gynecology and Obstetrics | 1981

Referat Coexistente prämaligne Proliferationen in Mastektomiepräparaten

Gertfried Schweikhart; M. Mitze; Werner Bocker

Zur Prfifung der Frage, auf welchem morphologischen Boden und aus welchen Vorstufen das Mammakarzinom entsteht, untersuchten wir in 110 Mammaamputationsprfiparaten bei Karzinomen unter 5 cm Gr6Be den PE-Rand, die Mamille und alle vier Quadranten unter getrennter Bezeichnung auf das Vorkommen von prfikanzer6sen und mastopathischen Verfinderungen. Die jeweils gefundenen h6chstgradigen Proliferationen teilten wir topographisch in einen tumorfernen und einen tumornahen Bereich ein. Tumornah ist dabei das Gewebe des Quadranten, in dem der Primfirtumor lokalisiert ist unter Ausschluf3 des direkten Tumorrandes; tumorfern sind die iibrigen drei nichtkarzinomat6s infiltrierten Quadranten. Die Dignitfitsbeurteilung der proliferativen Verfinderungen erfolgte nach der Einteilung in Mastopathie I I I I nach Prechtel unter differenzierter Berficksichtigung der von Azzopardi vorgeschlagenen Kriterien. Danach werden Mastopathie I I I als benigne Verfinderungen angesehen, Mastopathie III und Carcinoma in situ (ductal und lobulfir) als prfimaligne Proliferationen gewertet. Danach fanden sich tumornah in 75%, tumorfern in 86% der Ffille lediglich benigne Verfinderungen. In 22% konnte in karzinomat6s befallenen Quadranten ein Carcinoma in situ nachgewiesen werden, wfihrend eine Mastopathie III seltener in Tumornfihe als in der Tumorferne diagnostiziert wurde. Bei


Archives of Gynecology and Obstetrics | 1981

Die Bedeutung der Lymphangiosis carcinomatosa für die Prognose des Mammakarzinoms

M. Mitze; Gertfried Schweikhart; Werner Bocker; R. E. Herzog

189. M. Mitze, G. Schweikhart, W. B6cker, R. E. Herzog (Mainz): Die Bedeutung tier Lymphangiosis carcinomatosa fiir die Prognose des Mammakarzinoms Von insgesamt 136 von Januar 1977 bis Dezember 1978 in der UFK Mainz radikal operierten Mammakarzinomen konnten 109 Patientinnen regelmfigig in unserer Poliklinik nachuntersucht werden. Der Zeitraum der Nachuntersuchungen betrug wenigstens 20 und maximal 44 Monate. Im beobachteten Zeitraum traten bei sieben Patientinnen Lokalrezidive auf, etfmal kam es zu Fernmetastasen, zehn Patientinnen sind am Tumorleiden verstorben. In zw61f Ffillen, bei denen der Primfirtumor kleiner als i cm war, war auch in drei Ffillen bereits eine Lymphangiosis carcinomatosa (LC) nachweisbar. Aber die Mehrzahl der Fglle zeigte keine LC. In allen Ffillen war keine axillfire Lymphknotenmetastasierung nachweisbar. Bei 35 Tumoren von 1 2 cm Gr6ge war nut noch in 14% keine LC nachzuweisen; bei 31% bestanden bereits axillfire Lymphknotenmetastasen. War der Tumor 2 5 cm grog, so lieg sich in allen Ffillen auger einem einzigen eine LC nachweisen, bei 46% bestanden auch Lymphknotenmetastasen in der Axilla. War der Tumor gr613er als 5 cm, so bestand in allen Ffillen eine LC und bei 82% auch eine Lymphknotenmetastasierung. Bei den diffus fiber das ganze Drfisengewebe ausgebreiteten Tumoren waren LC und Lymphknotenmetastasen in allen Ffillen vorhanden. Bei isolierter Betrachtung der Beziehung zwischen regionfirer LC und dem Verlauf des Tumorleidens zeigt sich, dag in allen 15 Ffillen ohne LC keine Rezidive, Metastasen oder Todesffille beobachtet werden konnten. In 46 Ffillen mit nachgewiesener LC, aber ohne Lymphknotenmetastasen trat in 17% eine Progredienz des Tumorleidens ein. In 48 Ffillen, bei denen sowohl eine LC als auch Lymphknotenmetastasen bestanden, kam es in 42% zu einem Fortschreiten der Erkrankung. Als weiteren Parameter zur morphologischen Wertung der Mammakarzinome haben wir das histologische Grading herangezogen. Bei einem Grading von I wurde bei 13% der Ffille eine Progredienz beobachtet. Bei den Tumoren mit einem Grading von II kam es in 24% zu einem Fortschreiten der Erkrankung. Bei einem Grading yon III schlieglich fanden wir eine Progredienz in 56%. Wir haben versucht, aus den morphologischen Parametern eine Tabelle zur prognostischen Wertung der Tumoren herzustellen. Die Tabelle enthfilt die ffinf Faktoren: Lokalisation, Tumorgr6ge, histologisches Grading, regionfire Lymphangiosis carcinomatosa und axillfire Lymphknotenmetastasen.

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