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L Langbein

Publications and source records attributed to L Langbein.

At least 55 records · Page 3Linked to original sources
PubMed1989

Lectin histochemistry of human testicular germ cell tumors.

The lectin binding pattern (WGA, UEA-I, PNA, PSA, Con A, RCA and LCA) of 28 human testicular germ cell tumors (pure or combination tumors) was investigated. Lectin binding sites could be demonstrated in all germ cell tumor types. In classic and spermatocytic seminomas as well as seminomas with high mitotic index an equal distribution of lectin binding sites was observed. In embryonal carcinomas the lectin binding of UEA-I, PNA, WGA, LCA and RCA correlated to histological differentiation. A polarized staining of WGA, PNA, RCA and UEA-I, typical for embryonal carcinomas, yolk sac tumors and teratomas, was never seen in seminomatous tumors and may be of importance in differential diagnosis. By means of Con A decoration it was possible to distinguish cytotrophoblastic and syncytiotrophoblastic differentiation. Aspects of lectin histochemistry in tumor biology in general and in differential diagnosis of germ cell tumors in particular are discussed.

Choriocarcinoma↗
PubMed1988

In adequate tumor surgery of chemically induced soft tissue sarcomas--an experimental approach for induction of metastasis formation?

In preceding experiments with nude mice bearing xenotransplanted soft tissue sarcomas after inoculation of cultured sarcoma cells we attained a high percentage of metastatic dissemination by repeated inadequate tumor surgery. In the study presented here we used methylcholanthrene induced sarcomas (rhabdomyosarcomas and undifferentiated sarcomas in part showing the picture of storiform/pleomorphic malignant fibrous histiocytomas) which were produced in NMRI mice and examined (1) whether or not metastasis formation could be triggered or enhanced by repeated inadequate tumor surgery in these animals, and (2) the efficacy of the same surgical procedure following xenotransplantation of the tumors into nude mice. We did not reach an increasing frequency with both experimental arrangements. After discussing several factors which could be in general responsible for inducing metastasis formation and after comparing the results of our several experiments it is suggested that the methylcholanthrene induced soft tissue tumors may not contain cell clones able to metastasize.

Animals↗
PubMed1988

Intermediate filament typing in tumour diagnostics--an aid in histogenetic classification?

It is commonly accepted, that a histogenetic correlation can be established between tumour and mother tissue by means of intermediate filament typing. Recent results concerning the co-expression of different intermediate filaments within one cell, the occurrence of epithelial-specific intermediate filaments in soft tissue tumours, and the modulation of intermediate filament type expression caused by some bioactive substances and viral infections cast doubts on the general acceptance of the histogenetic classification of human tumours by intermediate filament typing. Its characterization determines only the actual morphological differentiation of the neoplastic cells and represents a valuable tool for the diagnostic assessment of the tumour under the viewpoint of the functional differentiation of its cells. A doubtless conclusion concerning the mother tissue of the neoplasia (histogenetic origin) is therefore not possible.

Animals↗
PubMed1988

[Fibroma of the tendon sheath. Diagnosis and differential diagnosis].

Ten cases of fibroma of the tendon sheath were examined by means of histological, topochemical, and immunohistochemical methods. Investigations were aimed at re-evaluation of histological variability and definition of diagnostic criteria. Microscopic observations suggested the following features to be typical of fibroma of the tendon sheath: Primitive mesenchymal or fibroblastic cells without further differentiation, slit- and cleft-like spaces with lining cells decorated by endothelial markers, and collagenous, cartilaginous or myxoid basic substance at least in areas rich with sulphated glycosaminoglycans. Differential diagnostic distinction of tendon sheath fibroma from myxoid cartilage tumors, fasciitis nodularis, and myxoid fibromatosis as well as from fibrohistiocytic lesions and giant cell tumors of tendon sheath is discussed with reference to the above definition.

Adult↗
PubMed1988

[Angiomyoma. A pathologo-anatomic analysis of 229 cases].

An analysis was made of 229 cases of angiomyoma retrieved from the authors' own files. Studies were aimed at histological features, morphological variability, tumour localisation as well as at distribution by sexes and age groups. The angiomyoma cases were subdivided by histological features into solid forms (18 per cent), venous forms (38 per cent), combinations (43 per cent), and cavernous variants (two cases only). That subdivision was based on variable relationships between smooth muscles, on the one hand, and vascular cavities of different shapes, on the other. Angiomyoma was found to occur in high incidence in the fourth to sixth decennium of age, with clearly recordable predilection for females, and localized in 40 per cent of all cases in the region of the lower leg. Noteworthy peculiarities included predominance of male patients with combined or mixed angiomyoma with cavernous components or with solely cavernous forms and preference of the venous subtype for the head-neck region. The morphological structure of angiomyoma is discussed in some detail and is interpreted as a correlate of an organoid mixed tumour with muscular and vascular components. It is against this background that the term of "angiomyoma" is definitely preferred to "vascular leiomyoma".

Adolescent↗
PubMed1987

Simple devices for the preparation of specimens for scanning and transmission electron microscopy.

A simple and inexpensive equipment especially for the dehydration of cells grown on coverslips in a continuous linear gradient is described. On this way it is possible to handle many objects simultaneously. The coverslips, even irregularly formed, are fixed vertically in simple silicon-rubber-holders. The device including a described special holder can also be used for thorough rinsing of EM-grids during the immunocytochemical labelling.

Desiccation↗
PubMed1987

Characterization of established epithelioid cell lines derived from rat liver: expression of cytokeratin filaments.

A number of epithelioid cell lines were established from livers of fetal and neonatal rats. The clear-epithelial cells of these lines are non-neoplastically altered, clonogenic, nearly-diploid and showed no hepatocyte-like properties. The distribution and organization of intermediate filaments were analysed by indirect immunofluorescence and immunoperoxidase techniques using polyclonal and monoclonal antibodies against cytokeratins and vimentin. The different keratin antibodies also react strongly with intermediate filaments of bile duct cells on frozen sections of fetal and neonatal liver. Several subcultures of all established cell lines contained cell populations which reacted positively with antibodies against prekeratin and broad-range cytokeratins in a different manner, but not with antibodies against cytokeratin No. 19 of the catalogue of MOLL. The intermediate filaments are arranged in predominantly stained pericellular rings as well as in fine filamentous networks more evenly distributed throughout the cytoplasm. In early passages almost all cells were found positive for pre- and cytokeratins whereas in later subcultures the number of positive cells decreases and the expression of cytokeratin polypeptides varies considerably as seen with the different antibodies. All cells of the different cell lines show a well developed fine filamentous vimentin network extending throughout the whole cell up to the outer cell margin. Our findings support the concept that the clear epithelioid cells in established cell lines are of epithelial nature but they are not derived from biliary epithelium, and therefore probably immature parenchymal liver cells.

Animals↗
PubMed1987

Adenomatoid tumors--mesotheliomas or not? A histochemical, immunohistochemical and light and electron microscopic (TEM/SEM) study.

A mesothelial, endothelial and epithelial differentiation of the adenomatoid tumors is discussed in the literature. Aimed at this problem the cellular nature of 12 adenomatoid tumors was investigated by means of histochemical and immunohistochemical methods at light and electron microscopic level. In all these neoplasias prekeratin was demonstrated while factor VIII-associated antigen and myoglobin were lacking within the tumor cells. The ultrastructural picture of the tumor cells was similar to that of mesothelial cells; abundant intermediate filaments of the keratin type could be decorated by means of the protein A-gold technique in them. Furthermore hyaluronidase sensitive glycosaminoglycans but no sulfated and neutral mucoproteins were found. The results suggest a mesothelial nature of the tumor cells of adenomatoid tumors.

Antigens↗
PubMed1987

[Localized fibrous mesothelioma of the pleura. Morphological studies of 7 cases].

Localized tumors of pleura should clearly be separated from diffuse pleural mesotheliomas due to clinical and pathological peculiarities. But there is some dispute on their proper interpretation and hence disagreement about their correct designation. Some call them "fibrous tumors (fibromas)" of pleura and appreciate by this term the fibroplastic potency of tumor cells and the lacking relation to overlying mesothelial surface cells, others prefer the name "fibrous mesothelioma" and allude to an at least abortive mesothelial differentiation within the tumor tissue. Examining 7 own tumor cases by means of light microscopic, topo- and immunohistochemical as well as electron microscopic methods the investigations were aimed at analysing the morphological structure of these tumors and subjecting it to a critical reappraisal with regard to a suited designation. Histologically, a marked variability of histological structure and texture was found, there were regions with similarities to fibromas, fibrous histiocytomas, hemangiopericytomas and nerve sheath tumors as well as blastema-like areas. Occasionally a vasoformative activity could be seen. In three tumors a few epithelioid cell complexes were visible, but neither keratin intermediate filaments nor UEA-I reactivity was to be demonstrated by immunohistochemistry. Antibodies against factor VIII associated antigen only marked endothelial cells of vascular structures. By the electron microscopic examination of 1 case abortive mesothelial differentiations were visualized (some lumen-like space formations, stub-like cellular projections of the cavity facing side, primitive intercellular junctions and fragmented basal lamina-like material). The findings inclusive the immunohistochemical results are discussed and jointly taken for sustaining the interpretation of these tumors as mesotheliomas and for militating against the classification as simple pleural fibromas or fibrous pleural tumors, respectively.

Adult↗
PubMed1987

[Stromal tumor of the testis with Leydig cell components. Light and electron microscopy analysis and fluorescence microscopy demonstration of F-actin].

A testicular gonadal stromal tumor with Leydig cells and mesenchymal cells resembling to Sertoli cells is presented. At the ultrastructural level most of the tumor cells could only be classified as endocrine differentiated cells. Because of their uncharacteristic organelles no Sertoli cells could be demonstrated by means of electron microscopy. The labelling of fibrillary actin underlines the cellular heterogeneity and the different cellular functional state of the tumor cells. These findings are interpreted as an evidence of a multidirectional differentiation potential of the gonadal stroma mesenchyme. These observations support the classification of these neoplasia as gonadal stromal tumors particularly in light of the clearly visible differentiation. Problems of evaluating the malignant potential of gonadal stromal tumors are also discussed.

Actin Cytoskeleton↗
PubMed1986

Modulation of expression of intermediate filaments during the development of established rat liver cell lines.

A number of clear epithelial-like cell lines were established from the liver of fetal and neonatal rats. The intermediate filaments of these cells were investigated using polyclonal prekeratin antisera, monoclonal antibodies against a cytokeratin subfamily and vimentin by means of the indirect immunofluorescence technique and SDS-PAGE analysis. Changes in the expression of cytokeratin filaments were found during the evolution of permanent cell lines. Cells positively stained for cytokeratins could be seen near to other cells which were negative. In early passages (up to the 40th) nearly all cells were strongly stained by the different keratin antibodies. During the following subcultivation the pattern of staining considerably changed. In FRL and NP-RL cell lines keratin-negative cells could already be observed in the early passages, rapidly increasing in the later passages. Compared to this, vimentin-staining of all cells remained constant in its morphological expression. The keratin filaments were seen in thick fiber bundles arranged particularly in the perinuclear ring as well as in finer networks throughout the cytoplasm. Every cell in the established lines showed their very individual staining pattern. The vimentin filaments extended to the whole cytoplasm up to the cell margin. Our observations demonstrate the variability of the system of keratin filaments in established epithelial-like liver cells under cultural conditions.

Animals↗
PubMed1986

[Papillary endothelial hyperplasia. Diagnosis and differential diagnosis].

There are only a few reports of papillary endothelial hyperplasia in the literature. Familiarity with the entity is important for the differential diagnosis of vascular tumors. The authors analyzed seven cases of papillary endothelial hyperplasia morphologically. Characteristic features include intravascular, endothelial-covered, papillary formations of varying size. Cellular atypia, pathologic mitotic figures and necrosis were absent. The presence of a single-layered endothelium and uniform cellularity as well as the absence of invasivity contribute to the differential diagnostic distinction from low grade angiosarcoma. The immunohistochemical demonstration of Factor VIII-associated antigen in the proliferative endothelium helps to demarcate the lesion in the event of the simultaneous occurrence of non-vascular mesenchymal tumors (3 cases). The pathogenesis of papillary endothelial hyperplasia is unknown. The possibility of a relation to thrombus organization and/or hormonal factors is discussed.

Adult↗
PubMed1986

[Intermediate filaments in cells of hyaline cartilage].

After different fixation procedures great numbers of bundles of intermediate cytofilaments, 10 nm in thickness, could be detected in electron micrographs of chondrocytes from Processus xiphoideus of the rat, from the articular cartilage of the rabbit and from chondrocyte cultures from the articular cartilage of the rabbit. By means of the indirect immunofluorescence technique with monoclonal antibodies they could be clearly defined as vimentin.

Animals↗
PubMed1984

[Morphological studies of triton-extracted cultured cell cytoskeleton].

The Coomassie Brillant Blue method of Pena (1980) was modified by use. The used method is simple and versatile for the investigation of morphological phenomena on the whole cytoskeleton of different cells in vitro. The additional advantage is the use of the specimens for the scanning electron microscopic observation after critical-point drying.

Animals↗
PubMed1977

[Postoperative vomitting and gastroatonia following aorto-bifemoral bypass operations during halothane-combination anaesthesia and neuroleptanaesthesia (author's transl)].

44 patients are analysed for the frequency of postoperative vomiting and the amount of gastroatonia following aorto-femoral bypass operations during neuroleptanaesthesia and halothane combination anasthesia. More than 60% of patients develop gastroatonia during both methods of anaesthesia. However it is less apparent on the first postoperative day after neuroleptanaesthesia and does not affect as many patients as after halothane combination anaesthesia. Postoperative vomiting is significantly more frequent after halothan combination anaesthesia than after neuroleptanaesthesia.

Adult↗
PubMed1977

[Early mortality in geriatric-gynecologic surgery].

The death rate of 6662 major gynaecological operations on women of 60 years or more in 17 West-Berlin Gynaecological Departments (1960--1969) was 7,7% (512 cases). Of these, 89 women (16,8%) died either during operation or within 3 days after the operation. In all cases there was an adequate indications for surgical intervention. With few exceptions the procedures of the operations could not be criticized. Only a very small part of the intra- and postoperative mortality could be attributed to the anesthesia. In some cases medication was insulfficient (e.g. lack of preoperative treatment with digitalis or postoperative replacement with substitutes or blood). This may partly be explained by the fact that during the period under investigation in many cases the anesthesia had to be done by the gynaecologists. Publications on early postoperative mortailty supply better information on the quality of medical care given to the gynaecological patients, than surveys of so called "Anaesthetic dealths".

Age Factors↗
PubMed1975

[Results in intensive care of older patients (author's transl)].

An increasing number of old on senile patients now submit to major surgery and intensive therapy for these patients is often indicated. The development in medicine has led to very good results being obtained in many of these cases. Patients this age-group may have pre-existing injuries, organ changes and restricted abilities to compensate, which means that when certain complications follow one must examine carefully the indication for continuing intensive therapy, in order to avoid needless and painful life-prolonging measures. Our own experiences with 54 patients are discussed.

Age Factors↗