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H Bouman

Publications and source records attributed to H Bouman.

12 recordsLinked to original sources
PubMed2000

Experimental autoimmune inner ear disease: an electrocochleographic and histophysiologic study.

Systemic immunization with swine inner ear antigens in complete Freund's adjuvant induces functional disturbances in the cochlea. Morphometric data indicate that an endolymphatic hydrops develops within 2 weeks. It diminishes 6 weeks after immunization. A progressive decrease in the compound action potential amplitude is observed from 2 to 6 weeks after immunization. Enhancement of the amplitude of the summating potential is present without a clear overall correlation to the presence of endolymphatic hydrops. The amplitude of the cochlear microphonics shows no significant changes after immunization. Western blot analysis of the sera performed 2 and 6 weeks after immunization shows enhanced reactivity at 68, 50, 45, and 27 kd molecular weights, as compared to controls. The same spectrum of cross-reacting antibodies is believed to be instrumental in immune-mediated sensorineural hearing loss in patients. Apparently, cross-reacting antibodies and released mediators disturb cochlear homeostasis, resulting in the observed changes in the electrophysiological responses. However, these changes are not clearly related to structural changes at the light and electron microscopic levels.

Animals↗
PubMed1998

Induction of endolymphatic hydrops in the guinea pig by perisaccular deposition of sepharose beads carrying and not carrying immune complexes.

We tried to induce endolymphatic hydrops in guinea pig cochleas by unilateral, perisaccular deposition of sepharose beads carrying immune complexes. Controls consisted of the deposition of sepharose beads without immune complexes and the contralateral, untreated ear. The effects of the treatment were studied by light microscopy and electrophysiological recordings of the gross cochlear potentials 1, 2, and 6 weeks after treatment. Each condition included six animals. Analysis of variance of the morphometric data concerning the ears treated with deposition of the beads showed a statistically significant difference (P = 0.04) between the degree of hydrops found for the beads with immune complexes and for those without. The difference between the treated ears and the contralateral untreated ears was significant (P = 0.01) for the beads with immune complexes and not significant (P = 0.8) for those without immune complexes while there was no significant effect of post-treatment time interval. Analysis of variance of the electrophysiological data, collected in response to tone bursts at the apex of the cochlea, showed no significant differences between the results for the beads with and without immune complexes. Therefore these results were pooled. One week after treatment the pooled results for the compound action potential showed a small decrease in amplitude, just significant at 2 kHz, but not at 4 and 8 kHz. This decrease disappeared completely after 6 weeks. The pooled results for the negative summating potential (SP) showed a significant increase in magnitude at all frequencies decreasing with post-treatment interval. The cochlear microphonics did not demonstrate any change in amplitude after treatment. The results indicate that deposition of sepharose beads with immune complexes induces endolymphatic hydrops. Also, deposition of the sepharose beads itself may have induced hydrops together with enhancement of the SP. SP enhancement may be related to the development of endolymphatic hydrops rather than to the presence of hydrops as such. This may be based on pressure build-up while hydrops develops.

Action Potentials↗
PubMed1991

Expression of intermediate filament proteins in the adult human cochlea.

The immunohistochemical localization of intermediate filament proteins was studied in frozen sections of chemically fixed, nondecalcified adult human cochleas. Cytokeratins were found in all epithelial cells lining the cochlear duct (including most supporting cells of the organ of Corti) but were absent in the hair cells. Neurofilament proteins were present in the nerve endings at the hair cells, in the neural bundles, and in the ganglion cells. Vimentin staining occurred in most of the supporting structures and was roughly complementary to the regions showing cytokeratin staining and neurofilament staining. However, the region of the spiral prominence and outer sulcus, as well as the pillar cells and Deiters' cells in the organ of Corti, showed coexpression of vimentin and cytokeratins. No definite immunostaining was observed with antibodies to desmin and glial fibrillary acidic protein.

Adult↗
PubMed1979

Influence of whole body irradiation on intraperitoneal immunity in a syngeneic mouse lymphoma system.

DBA/2 mice were immunized against the syngeneic SL2 lymphoma by two injections with irradiated lymphoma cells or by two injections with irradiated cells followed by one injection with unirradiated cells. Whole body irradiation (500 rad) of the immunized mice caused a significant decrease in the number of peritoneal macrophages and lymphocytes. The spleen weight showed a transient decrease. However, whole body irradiation did not cause a significant decrease of the survival time of immunized mice challenged intraperitoneally with SL2 lymphoma cells.

Animals↗
PubMed1978

Demonstration of immunoglobulin production by tumor cells in non-Hodgkin's and Hodgkin's malignant lymphomas and its significance for their classification.

Combined application of morphologic, immunochemical, and immunologic methods has led to a reinterpretation of non-Hodgkin's lymphomas and to the establishment of the Kiel classification. In the present paper, the main Ig-producing entities are considered. These are: 1. Chronic lymphocytic leukemia of the B-type (B-CLL)--a proliferation of lymphocytes and a few so-called prolymphocytes and lymphoblasts. The mean tissue IgM value is slightly increased; the serum IgM level is normal or reduced. The tumor cells bear SIg, and a majority of them have a receptor for C3d but always lack CIg and are usually devoid of receptors for C3b. 2. Lymphoplasmacytoid immunocytoma--a mixed proliferation of lymphocytes and centrocytes, blast cells, plasma cells, or plasmacytoid cells. The tissue Ig content is most often (91%) and most highly increased in this group, whereas the serum Ig level is increased in only 20% of the cases. The tissue IgM of 17 cases was shown to be monoclonal by IEF. Most tumor cells have SIg and a variable numbear CIg. The tumor cells bear both complement receptor subtypes, only a receptor for C3b, or no complement receptors at all. 3. Centroblastic/centrocytic lymphoma--usually a follicular proliferation of abundant small germinal center cells (centrocytes) and some large germinal center cells (centroblasts). The tumor cells bear SIg and both complement receptor subtypes. The C3b- and C3d-positive cells are located in the follicles, as in nonneoplastic lymphatic tissue. 4. Centrocytic lymphoma--a purebred, diffuse proliferation of the small germinal center cells (centrocytes). These cells bear SIg and receptors for C3b and C3d but usually lack CIg. 5. Centroblastic lymphoma--a proliferation of the large germinal center cells (centroblasts). 6. Lymphoblastic lymphoma of Burkitt's type. 7. Immunoblastic lymphoma--a diffuse proliferation of large basophillic cells resembling immunoblasts. The tissue IgM content is increased in 60% of the cases. It proved to be monoclonal with IEF in all five cases studied. The cells of five cases with increased tissue Ig content bore SIg. Nearly half of the cases studied showed CIg. Besides non-Hodgkin's lymphomas, paraffin sections of 87 biopsies from Hodgkin's disease were investigated for CIg in Hodgkin's and Sternberg-Reed cells. These cells stained positively in 68 cases, most often for IgG, followed by IgD. In five cases of the lymphocyte-depleted type, the staining of the Hodgkin's and Sternberg-Reed cells was restricted to one light chain type.

Burkitt Lymphoma↗
PubMed1975

Microheterogeneity of Immunoglobulin G from plasmocytomas. Identification of two types of IgG by isoelectric focusing.

Isoelectric focusing of serum immunoglobulin G (IgG) revealed that the microheterogeneity, which is expressed in the isoelectric points (IEP), partly is caused by differences in the content of N-acetyl-neuraminic acid (NANA), partly by other effects, probably including deamidation. Two different types of Plasmocytoma-IgG, which differ in IEF-pattern, i.e. population distribution, in sensitivity towards neuraminidase and in carbohydrate content, are described. The contents of carbohydrates in these 2 IgG-types are up to 30% greater and 50% less, respectively, than that of normal IgG. A precise correlation was found between the total content of NANA in moles per mole IgG-monomer and the shift in band-IEP on hydrolysis catalyzed by neuraminidase. This may be used for a rapid estimate of NANA in IgG. The results do not permit a discrimination between an anabolic and a catabolic origin of the heterogeneity in the carbohydrate moiety of IgG.

Antibodies, Heterophile↗