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Biomedical subjects

W Arnold

Publications and source records attributed to W Arnold.

At least 307 records · Page 17Linked to original sources
PubMed1982

[Morphologic studies of the toxicity of ethacrynic acid in the spiral prominence].

Ultrastructural changes in the guinea pig spiral prominence were studied at various times after a single intravenous injection of ethacrynic acid (40 mg/kg body-weight). Initial swelling of endolymph-facing epithelial cells was followed by dilatation of the intercellular spaces and marked shrinkage of the stroma cells surrounding the spiral prominence vessel. While the changes in the stria vascularis and the spiral prominence progressed at about the same pace, the regression to normal ultrastructure set in earlier in the spiral prominence.

Animals↗
PubMed1982

Functional and morphological findings of endolymphatic sac.

After obliteration of endolymphatic sac and duct, no significant alteration in d.c. potential, K+ activity or protein content during the development of endolymphatic hydrops could be observed. The K+ activity of endolymphatic sac was only one-ninth of that in the cochlear part of the endolymph. After injection of Thorotrast into the endolymphatic sac, aggregated particles were found in the cochlear endolymph 2 days later. Ethacrynic acid (60 mg/kg) caused a decrease in K+ activity in the cochlear endolymph, but an increase in the endolymphatic sac. Intercellular edema was observed both in stria vascularis and in endolymphatic sac by light and electronmicroscopy after ethacrynic acid administration. These results suggest the existence of an active transport mechanism in the endolymphatic sac epithelium.

Animals↗
PubMed1982

[Antimitochondrial antibodies against the M2-antigen with immune vasculitis and discoid lupus erythematosus without proof of liver disease].

We have seen a 54-year-old patient with discoid lupus erythematosus and biopsy-proven vasculitis with granular deposits of complement and immunoglobulins in small subcutaneous vessels of clinically normal skin. Serologically, neither antinuclear antibodies nor antibodies against double-stranded DNA, Sm-Ag nor ribonucleoprotein could be demonstrated whereas the immunofluorescence test for antimitochondrial antibodies was positive during the whole observation period of 15 months. The further characterisation of the antimitochondrial antibodies by a newly described radio-immuno-assay demonstrated that the antibodies are directed against the primary biliary cirrhosis specific M2-antigen of mitochondria. So far, the patient, however, does not show any clinical or laboratory signs of primary biliary cirrhosis and a liver biopsy showed no evidence of that disease. It is discussed whether there is a coincidence of different autoimmunopathies or if the findings are symptoms of a single disease. Follow-up study might solve this open question.

Antigens↗
PubMed1982

Biological characterization of cells derived from a human breast carcinoma. I. Some characteristics of cells cultivated in vitro prior to and after transplantation into nude mice.

Single cells from a patient (B. E., 65 years) have been isolated by collagenase treatment and cultivated in vitro. The human tumour of the mammary gland showed predominantly simple undifferentiated and also tubular structures. The 5th in vitro passage of these cells was characterized by DNA-distribution pattern, cell doubling time, chromosome number, ultrastructure, hormone and drug sensitivity. Cells of the 5th in vitro passage were i.p. transplanted into nude mice. The characteristics of in vitro cultivated cells (5th in vitro passage) were compared with both ascitic cells (1703/A) and cells of solid tumour material (1703/S) grown in nude mice for several passages (0, 10, 21). DNA-distribution patterns, chromosome numbers and cell doubling times are in good correlation. The number of polyploid cells is increased in ascitic cells. These malignant cells are best able to proliferate in vitro after transplantation into nude mice. Ultrastructure examination of the 21st passage has shown similarity between cultured cells, ascitic cells and cells of solid tumour material grown in nude mice. Virus particles could be observed in cells of solid only. Estrogen binding could be observed in the original tumour material only. All other cell or tissue preparations contained no receptors. Drug sensitivity was changed in the case of Vinblastin, Daunoblastin and Sarkolysin treatment of cells of solid tumour material more than in ascitic cells grown in nude mice. The environment dependence of cells and biological differences between in vivo-in vitro tumours and human neoplasms has to be taken into account when using cells as in vivo or in vitro model systems in experimental and clinical cancer research.

Aged↗
PubMed1982

Winding anomalies in nuclear DNA from malignant cells. I. Experimental evidence.

The superhelical properties of nuclear DNA from malignant cells of human origin (leukemic cell lines Reh and D-562, mesothelioma cell line, and peripheral blood monocytes from acute monocytic leukemia) were investigated in neutral sucrose gradients with ethidium bromide. As compared with the universal superhelical density of nuclear DNA from normal cells, the DNA released from malignant cells showed a substantially higher negative superhelix content, equivalent to an increased deficiency in right-handed DNA duplex turns. In regard to analogous results obtained from other malignant cell systems, the extremely underwound structural state of nuclear DNA appears to be a feature common to malignant cells.

Cell Line↗
PubMed1981

IgM antibody to hepatitis B core antigen (anti-HBc IgM) in "healthy" HBsAg carriers: a longitudinal study of 75 cases.

In 75 healthy HBsAg carriers with normal liver tissue who were followed over a four years period, anti-HBc IgM was determined by ELISA. 61 HBsAg carriers (81%) were positive for anti-HBc IgM at first investigation. 54 individuals demonstrated persistence of anti-HBc IgM, 7 became anti-HBc IgM-negative within the observation period. 12 persons were persistent anti-HBc IgM of low quantities. 3 of 4 individuals with HBsAg clearance demonstrated a considerable decrease of anti-HBc IgM concentration. Although signs of liver damage or development of chronic liver diseases were not observed at the time of control biopsy the existence of anti-HBcIgM indicates that there exists also in healthy HBsAg carriers a persistent stimulation by HBcAg, inducing the production of anti-HBc IgM as a sign of permanent ongoing virus B replication. These results require a new and critical review of the "healthy" HBsAg carrier state.

Antibodies, Viral↗
PubMed1981

Quantitation of HBeAG and anti-HBe by RIA in sera of chronic HBsAG carriers and individuals with type B hepatitis.

This paper gives the results for HBeAg and anti-HBe titers in chronic HBsAg carriers and patients with type B hepatitis using a "solid-phase" radioimmunoassay. In tumor and hemodialysis patients the HBeAg titers are statistically significant higher compared to the group of HBsAg positive CAH or CPH. High anti-HBe titers are a characteristic finding in "healthy" HBsAg carriers. On the other hand, there is a subgroup of HBsAg positive CAH with anti-HBe; although there are signs of an ongoing virus B replication these cases of CAH proceed sometimes to cirrhosis.

Acute Disease↗
PubMed1981

Studies on anti LSP autoantibodies in acute and chronic non-B hepatitis -- evidence for the lack of anti LSP in non-A, non-B (NANB) viral hepatitis.

The prevalence of autoantibodies against the liver membrane antigen LSP (anti LSP) has been studied in acute and chronic non-B hepatitis. Anti LSP autoantibodies were detected in five of eight patients with type A and in two of 18 patients with type non-A, non-B (NANB) acute hepatitis. No statistically significant difference was observed between the group of anti LSP positive and anti LSP negative cases of acute non-B hepatitis concerning age, serum glutamic pyruvic transaminase (SGPT), and serum bilirubin levels. In hepatitis A SGPT and bilirubin levels were significantly higher as compared to type NANB acute hepatitis. Sera which were positive for anti LSP in the acute phase were negative within 2 months from onset although the two anti LSP positive patients hepatitis (CPH). None of 27 patients with chronic NANB hepatitis displaying the morphology of CPH were anti LSP positive; in contrast, six of nine patients with autoimmune type chronic hepatitis were anti LSP positive, displaying the morphology of chronic active hepatitis. In conclusion, in acute hepatitis anti LSP autoantibodies are a consequence of liver cell destruction rather than being involved in the mechanism of liver cell necrosis. Anti LSP autoantibodies are unlikely to play an important role in the development of chronic NANB hepatitis.

Acute Disease↗
PubMed1981

Hepatitis-B virus-associated deoxyribonucleic acid polymerase: a partial characterization by the use of chemical agents.

The very limited coding capacity of the HBV-DNA led us to study the nature of the HBV (Dane particle) -- associated DNA polymerase. The HBV-associated DNA polymerase met in many respects the characteristics of the repair enzyme of the host: the DNA polymerase beta. It operates under high salt conditions, and exhibits similar salt effects with NaCl, KCL, and PO4(3-). It is insensitive to sulfhydryl group blockers, such as p-hydroxymercuribenzoate and N-ethylmaleimide, is resistant to phosphonoacetic acid, and not inhibited by 5 mol/l urea. It requires a divalent cation (Mg2+) for activity, the Mg2+ concentration revealing optimal activity is somewhat higher than that described for most DNA polymerases beta. The HBV-associated DNA polymerase differs also from most DNA polymerase beta in its sensitivity ot ddTTP and its optimal pH. The fact that DNA polymerase beta of different origin vary considerably in their response to chemical agents and that the DNA polymerase beta from human liver has not been studied allows no definite conclusion as to the nature of the Dane particle-associated DNA polymerase.

Chemical Phenomena↗
PubMed1981

Demonstration and partial characterization of an intermediate HBcAG (Dane particle) population.

Hepatitis-B core antigen (HBcAg) was released from Dane particles previously separated from anti-HBc by repeated pelleting through sucrose gradients separated into three HBcAg populations when analysed by cesium chloride density gradient centrifugation. Heavy HBcAg particles banded at a density of 1.355 gm/ml, intermediate HBcAg particles at a density of 1.33 gm/ml, and light mediate HBcAg particles at a density of 1.30 gm/ml. Like heavy HBcAg particles, intermediate HBcAg particles contained DNA polymerase activity, but the ratio of HBcAg to DNA polymerase activity was significantly different in both populations. Intermediate HBcAg particles could not be separated from heavy HBcAg particles by rate sedimentation centrifugation. The size of the HBV-DNA and the size of its single-stranded gaps were not significantly different in heavy and intermediate HBcAg populations. Data accumulated in this paper suggest that the intermediate HBcAg particle differs from the heavy HBcAg particle by the amount of HBcAg polypeptides and the number of HBcAg determinants exhibited.

Centrifugation, Density Gradient↗