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Biomedical subjects

W Arnold

Publications and source records attributed to W Arnold.

At least 415 records · Page 23Linked to original sources

Anti-HBc titers in HBeAg and anti-HBe positive asymptomatic HBsAg carriers.

A study was undertaken to establish markers for HBV replication in relation to HBeAg and anti-HBe. HBsAg carriers with serum HBeAg had DNA polymerase activity in the serum and HBcAg in the liver nuclei. Anti-HBe positive and anti-HBe/HBeAg negative sera lacked these markers. For anti-HBc the following geometrical mean titers were calculated: 1: 12,000 for HBeAg positive, 1:9, 100 for anti-HBe and anti-HBc positive, and 1:2,800 for anti-HBc positive anti-HBe/HBeAg negative asymptomatic HBsAg carriers. Follow up studies revealed mostly unchanged anti-HBc titers in all three groups over an observation period of ten to twenty months. Our data argue for a prolonged HBV replication in all HBsAg carrier subgroups compared to individuals with an uncomplicated acute virus-B-hepatitis. This study gives no final answer whether HBeAg negative HBsAg carriers have a continous HBV replication.

Antibodies, Viral↗

Sources of endolymph and EP. Does the perilymph or Reissner's membrane influence the ionic content of the endolymph and EP?

The source of EP and the production of the endolymph are often considered to be at the stria vascularis. However, the significance of Reissner's membrane in maintaining the ionic composition of the endolymph cannot be ruled out. We perfused the entire perilymphatic space of guinea pigs with paraffin oil to determine the effects on the endolymph and perilymph. After 1 and 2 h the endolymph was removed from the second turn and the ionic concentration of these samples was measured by flamephotometry. The results revealed no significant changes in Na+ and K+ concentration as compared to normal endolymph. EP was measured from the second turn under an equivalent experimental condition. During 1 h of oil perfusion, EP remained fairly constant. From these experiments we surmise that perilymph and Reissner's membrane do not influence the ionic composition of the endolymph and EP during 1 or 2 h of our experiments.

Animals↗

[Active otosclerosis of the stapes footplate: histological and clinical aspects of its influence on the perilymph (author's transl)].

Pathologic capillaries are usually seen in the center of an otospongious process. Next to obliteration, dilatation and increased permeability a loss of basement membrane structure is evident. Around the capillaries exists a wide network of mesenchymal cells which have a glycogen like mass within the cytoplasm; glycogen can be delivered into the extracellular fluidspace. Free erythrocytes are located around many vessels. Near the margin of the lacunae decalcificated areas are seen; in the center of these areas osteocytes undergo lysis; they show intracytoplasmatic deposits of apatite which we assume to be located within the mitochondria. The collagen structure in the neighbourhood of the osteocytes seems to be damaged. Once the resorptive process has reached the perilymphatic surface of the footplate there comes to an connection between the otospongiotic lacunae and the vestibule. Free erythrocytes, glycogen like drops and lysosomes are delivered into the perilymph. Comparing the histological results with the operative results in patients with floride otosclerosis we conclude that operation should be done as early as possible to prevent damage from the inner ear, caused by the continuous intoxication of the perilymph from the otosclerotic focus.

Bone Resorption↗

[The reactions of human middle ear mucous membrane (author's transl)].

Healthy middle ear mucous membrane of newborns differs from the respiratory mucous membrane of the respiratory tract, in that it lacks a mucociliary epithelial pattern and because it has an absence of cells responsible for immunological resistance. Irritations over a short period of time and intensity cause a mucous membrane edema, which leaves behind, when the irritation disappeares, no permanent morphological changes in the structure of the mucous membrane. Severe irritations over a long period of time cause a characteristic change in the epithelium and submucosa: the single layered flat epithelium is replaced by respiratory epithelium; in the submucosa a proliferation of the connective tissue occurs simultaneously with the development of a local immunologically potent, cellular defense system. The actively secretive epithelial cells serve as the means whereby the antibodies are transported to the surface of the mucous membrane. Whereas at the time of mucous membrane edema, serum components (transsudate) are the primary source of the resulting "serotympanum", an increase in viscosity of the mucous allows one to recognize the active secretive work of the metaplastic epithelium. The biochemical composition of the various effusions givens a direct a direct indication of their origin: it is, however, no key to the cause! Only in the case of purulent secretions is it possible to recognize the cause by cellular or bacteriological identification. The same is valid for the norphological changes of the middle ear mucous membrane since the membrane will generally react in a similar manner, even though the types of irritation differ. When the stimulus which brought about the proliferation of the mucous membrane since the membrane will generally react in a similar manner, even though the types of irritation differ. When the stimulus which brought about the proliferation of the mucous membrane and the epithelial metaplasy disappears, the active production of mucous stops. However, a regression to the original condition does not take place: the mucous membrane remains ready to react!

Animals↗