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H Metzger

Publications and source records attributed to H Metzger.

At least 181 records · Page 10Linked to original sources
PubMed1978

[Endocervical form of the vaginal adenosis (author's transl)].

Vaginal adenosis is a rare kind of disease without specific symptoms and does not represent a very serious disorder from the beginning. Concerning the etiology teratogenetic dependencies are known which still are interpreted in different ways in the recent literature. The increased number of cases, including those with clear-cell-carcinoma of the vagina, in juveniles after exposition to DES during the early embryonal development shows in particular (Central index for the stilbestrol-adenosis-carcinoma-syndrome in the USA, since 1971) a wrong pathway in the organogenesis of cervix and vagina. This occurs at the interference zone between the epithelium of the Müllerian ducts and the epithelium of the sinus urogenitalis of the female fetus and in so far constitutes the origin of vaginal adenosis. The basics of the possibility of the development of such irregular differentiation and heterotopic dissemination are proven again by the case report of a vaginal adenosis showing the highly differentiated endocervical type. Not every case of vaginal adenosis does signify a precancerous lesion. The separation of the most frequently endocervical manifestation observed from endometrial and intermediate forms might be difficult. A positive distinction is prognostically essential, however, since clear-cell-carcinomas of the vagina are known in occurence with the endometrial type of vaginal adenosis only. Scanning electron microscopy as a method to follow tissue organization reveals the way of differentiation between the various types via ultrastructural analysis for vaginal adenosis is an example for failures of developmental organization. The same analysis is feasible in cytological smears also. The therapeutic requirements of vaginal adenosis depend on the tissular differentiation and the given local extent of the adenomatous lesions.

Adult↗
PubMed1978

Triggering of cultured neoplastic mast cells by antibodies to the receptor for IgE.

Cell surface receptors for IgE were isolated from detergent lysates of iodinated, IgE-saturated, rat basophilic leukemia cells by precipitation with anti-IgE antibodies followed by chromatography at acid pH. The isolated material showed a single 125I-band (m.w. approximately 58,000) on gel electrophoresis in sodium dodecyl sulfate and was used to immunize a rabbit. The resulting anti-serum was reacted with lysates of surface iodinated mouse or rat tumor mast cells. Analysis of the precipitates on (10%) gel electrophoresis revealed one major peak comprising greater than 80% of the detectable counts and having an estimated m.w. of approximately 58,000. The antiserum reacted with detergent-solubilized and cell-bound receptors in the presence or absence of excess IgE; it also inhibited the binding of 125I-IgE. Cultured mouse mastocytoma cells never exposed to IgE released 3H-serotonin when incubated with F(ab')2, but not Fab' fragments of the antiserum, which had been rigorously freed of IgE and anti-IgE. The release was inhibited in the presence of excess IgE, was Ca++ dependent, and equaled 80% of the maximum obtained with IgE and anti-IgE. We conclude that aggregation of the receptors for IgE provides the critical signals for cell activation.

Animals↗
PubMed1977

Assay and partial characterization of the solubilized cell surface receptor for immunoglobulin E.

The cell surface component (receptor) which specifically binds immunoglobulin E (IgE) presumably forms an integral part of the functional chain involved in the antigen-induced IgE-mediated degranulation of histamine-containing mast cells and basophils. This paper describes a simple (NH4)2SO4 predipitation assay with which the interaction of IgE with detergent-solubilized receptors can be reproducibly quantitated. Receptor saturation was demonstrated and a linear response to receptor concentration over at least a 30-fold rang obtained. By means of the assay it was shown that (a) all assayable receptors of rat basophil leukemia cells are cell surface expressed; (b) receptor specificity remains intact during solubilization; (c) the binding constants of the solubilized IgE receptors are similar to those determined on intact cells. Utilizing agarose gel filtration, preliminary estimates of the molecular weight of the active free solubilized receptor and of its complex with IgE suggest that the receptor is univalent.

Ammonium Sulfate↗
PubMed1977

Molecular weight and valence of the cell-surface receptor for immunoglobulin E.

The molecular weight of the active solubilized cell-surface receptor for immunoglobulin E (IgE) was measured in nonionic detergent. The diffusion coefficient was estimated by gel filtration, the partial specific volume was estimated from the differential sedimentation in sucrose gradients prepared from H2O and D2O, and the sedimentation constant was estimated from the same centrifugation experiments. The receptor has an apparent molecular weight of 130,000. Its high partial specific volume (0.81 cm3/g) suggests that bound detergent contributes significantly to the mass. The molecular weights of the receptor-IgE complex and of unbound IgE determined similarly were 310,000 and 200,000 respectively, clearly showing that the receptor is univalent. The implications of these results for the subunit structure of the receptor, receptor-membrane integration, and a possible mechanism of receptor triggering are discussed.

Animals↗
PubMed1977

Dimeric immunoglobulin E serves as a unit signal for mast cell degranulation.

Rat immunoglobulin E (IgE) was treated with a crosslinking reagent, dimethyl suberimidate, and fractionated by gel filtration into monomers, dimers, trimers, and higher polymers. The fractions retained substantial ability to bind specifically to mast cells. About one-third of the cell-bound dimers appeared to bind bivalently. The fractions were assayed in vivo by passive cutaneous anaphylaxis in rats, and for histamine or serotonin release in vitro using normal or tumor mouse mast cells. The monomers showed no activity, while the dimers and higher polymers gave excellent and approximately equivalent responses. We conclude that IgE that has been crosslinked to form dimers prior to the addition to mast cells can serve as a unit signal for triggering IgE-mediated exocytosis.

Animals↗
PubMed1977

Noncytotoxic IgE-mediated release of histamine and serotonin from murine mastocytoma cells.

Cultured murine mastocytoma (AB-CBF1-MCT-1) cells were stimulated to release endogenous or incorporated histamine or serotonin by an IgE-mediated mechanisms without loss of viability. Stimulation was achieved by incubation of the cells with rat IgE-anti-IgE, rat IgE-anti-light chain, fluoresceinated rat IgE-anti-fluorescein, IgE-enriched mouse anti-ovalbumin-ovalbumin, or covalently linked dimers of rat IgE, at doses similar to those optimal for normal peritoneal mast cells. Active cell metabolism and Ca++ were required to obtain release. Despite the latter, no dose of the calcium ionophore, A23187, could be found which caused release without concomitant cytotoxicity. Phosphatidylserine did not enhance release.

Animals↗
PubMed1976

The re-epithelization of endometrium after menstrual desquamation.

MATERIALS: Human uteri were removed by vaginal hysterectomy on the first, second and sixth day of the menstrual cycle. METHOD: Washing, pinning, fixation in glutaraldehyde 2.5%, dehydration in ascending concentration of ethanol, critical point drying with carbon dioxide, sputter coating with gold. RESULTS: The re-epithelization of the endometrium starts immediatley after the onset of menstrual bleeding due to desquamation of the premenstrual endometrium. The remaining stumps of endometrial glands after the endometrial break-down, proliferate rapidly, forming marginal collars. Up to the sixth day the proliferative process has produced a continuous layer of fusiform cuboideal epithelial cells, which cover the entire endometrial surface of the uterine cavity. The dynamics of epithelial growth can be "seen" in following three subsequent stages of the process and in analyzing the arrangement of the cells around the openings of the endometrial glands. Accordingly ciliogenesis occurs in some surface endometrial cells. The paper gives an inconographic survey of the early proliferative phase, illustrating changes from glandular epithelium to the lining epithelial layer and ciliogenesis in the latter. The new formation of ciliae in endometrial epithelial cells is an unique phenomenon, being influenced by the cyclic endocrine regulation of the endometrial function in human reproduction.

Adult↗