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Biomedical subjects

W Arnold

Publications and source records attributed to W Arnold.

At least 289 records · Page 16Linked to original sources
PubMed1984

[Significance of autoantibodies in the diagnosis of non-A, non-B hepatitis].

Various autoantibodies against different components of the hepatocytes have been demonstrated in chronic active hepatitis (CAH) which is an etiologically heterogeneous disease. These antibodies are essentially antinuclear antibodies (ANA), antibodies against liver cell membranes (LMA), antibodies against a microsomal antigen from liver and kidney (LKM), antibodies against soluble liver antigen (SLA) and antimitochondrial antibodies (AMA). These various autoantibodies mentioned could not be demonstrated in 18 patients with clearly established acute and 27 patients with clearly established acute and 27 patients with clearly established chronic hepatitis non-A-non-B. In addition these autoantibodies could not be found in our own cases of clearly established hepatitis non-A-non-B after the acute stage of the disease. Testing for the presence of these antibodies thus helps essentially to differentiate the autoimmunologically caused form of CAH from the CAH non-A-non-B.

Adult↗
PubMed1984

Investigations on the instability of drug sensitivity in dependence on culture and transplantation conditions in case of a human lung carcinoma.

Changes of biological properties, DNA-distribution patterns and drug sensitivity testing in vivo and in vitro after different culture and transplantation conditions in case of a human lung carcinoma are described. While DNA-distribution patterns of cells before any culture (OSC, TC 0) showing two clearly different aneuploid cell populations (DNA-index DI: 3.9 and 4.9), cells after 8 passages (TC 8) in vitro demonstrate only one cell population. These cells do not differ from double value (4C) of diploid cells (2C). DNA-distribution patterns of cells of solid tumors grown in nude mice (nu/nu 2089-1) show a cell population with DI 6.3. In line with these results, cells and tissues after different culture and transplantation conditions exhibit variable drug sensitivities. The lung carcinoma (OSC) shows clear reactions measured either by 3H-thymidine or 3H-deoxyuridine in the presence of Cyclophosphamide and Methotrexate. Adriblastin and 5-Fluorouracil did not show any effects after 48 hours treatment. Cultivated cells (TC 8) were sensitive against all antineoplastic drugs tested. Tumor tissue grown in nude mice (nu/nu 2089-1) shows the strongest effect after 5-Fluorouracil treatment both in vitro and in vivo. Selection of different cell population were discussed with regard to these findings.

Adenocarcinoma↗
PubMed1984

[Amebic colitis - differential diagnosis of ulcerative colitis and Crohn disease].

Amoebic colitis rarely develops in patients who had not stayed in a country where amoebiasis is endemic. "Crohn's colitis" was diagnosed in a 33 year old female patient who never had stayed in such an area. The dramatic deterioration of the disease led to revise the early diagnosis. The reported case indicates that the conventional laboratory, endoscopic, histologic, and radiologic examinations don't prove the anamnestically unsuspected amoebic colitis. Since the correct diagnosis was verified by stool and serologic examinations, these should be performed in any doubt of a specific colitis.

Adult↗
PubMed1984

[In vitro cell and tissue cultures as a model for studying human tumors].

An experimental in vitro or in vivo tumour model should be unchanged represent the biological properties (e.g. histology, proliferation). Changes of tumour cell populations were determined by means of DNA-distribution and multinucleation after cytochalasin B treatment. Flow cytometry measurements on cell cultures in 50 ml glass culture flasks reveal reduction of polyploid cells after collagenase treatment of human mammary carcinomas. Selection of cell populations are responsible for the failed induction of multinucleation by cytochalasin B. In organ cultures the composition of cell population prior to and after 48 hours could maintained. The improved penetration could be demonstrated by autoradiographic measurements of 3H-thymidine incorporation. Thickness, surface and improved penetration of metabolites of vital tissue slices seem to be also important for cell movement and cell division. In 10 out of 12 experiments an earlier cell migration and proliferation could be observed from vital slices than from tissue pieces. Organ cultures represent sufficiently carcinoma in vivo and are more suitable than other mentioned in vitro cell culture methods.

Autoradiography↗
PubMed1983

[Experimental studies on the effect of labyrinth anesthesia].

Injection of tetracaine into the tympanic cavity inhibits, independently of histologic lesions of the round window membrane, the active electrogenic pump in the stria vascularis cells. The DC potential in the endolymph is reduced with increasing doses of tetracaine, while the K+-Cl- activity is unchanged for 120 min. This drug does not alter the permeability of Reissner's membrane. Near the stria vascularis area, the oxygen pressure in the endolymph increases significantly after the effects of 4% tetracaine.

Anesthesia, Local↗
PubMed1983

Fluorocarbon cardioplegia and myocardial protection.

This study compares myocardial protection using nonoxygenated clear cardioplegia with oxygen-carrying solutions of blood (PO2, 100 mm Hg) and fluorocarbon (FC-47 perfluorotributylamine, PO2, 500 mm Hg), all containing 25 mEq/L of potassium chloride. Three groups of dogs, each consisting of 5 animals, were placed on cardiopulmonary bypass, and the aorta of each dog was cross-clamped for 45 minutes. Hemodynamic and biochemical variables were measured at baseline and during recovery. Levels of the myocardial isoenzyme of creatine phosphokinase (CPK-MB) in the coronary sinus were significantly lower in the fluorocarbon cardioplegia group at 15 minutes of aortic cross-clamping (p less than 0.01), while both the fluorocarbon and blood cardioplegia groups demonstrated lower CPK-MB levels at 45 minutes (p less than 0.001 and p less than 0.05, respectively), compared with the clear cardioplegia group. The blood and fluorocarbon groups had improved mean aortic blood pressure (p less than 0.02 and p less than 0.05, respectively) and left ventricular pressure. At 45 minutes of reperfusion and recovery, all hemodynamic and enzymatic variables were similar in each group. We conclude that oxygenated solutions better protect the myocardial cell, but that further work is needed to determine the most effective oxygen level for maximum protection with cardioplegia.

Animals↗
PubMed1983

Energetics of photosynthetic glow peaks.

By postulating temperature-dependent equilibria between two or more electron carriers acting as traps for electrons or holes, it is possible to modify the Randall-Wilkins theory of thermoluminescence so as to explain the abnormally large apparent activation energies and apparent frequency factors observed in photosynthetic glow curves when fitted by unmodified Randall-Wilkins theory. The equilibria serve to inhibit the formation of the light-emitting excited state by withholding the needed precursor state. When the inhibition is released at higher temperature by shift of equilibrium with temperature, the rise of the glow peak can be much faster than would result from Arrhenius behavior based on the true activation energy and so appears to correspond to a higher activation energy accompanied by a larger frequency factor. From another viewpoint, the enthalpy changes, DeltaH, of the equilibria tend to add to the activation energy. Similarly the entropy changes, DeltaS, of the equilibria tend to add to the entropy of activation, giving the large apparent frequency factors. The positive values of DeltaS needed would correspond to entropy decreases in the forward early electron transport. A comparison of the glow peaks obtained by different workers is also presented.

Journal Article↗
PubMed1983

Characterization of circulating immune complexes in chronic non-A, non-B hepatitis.

We studied the frequency and composition of circulating immune complexes (CIC) in patients with chronic persistent non-A, non-B (NANB) hepatitis and in convalescent persons after an apparently normal recovery from acute NANB hepatitis. 10 of 16 patients with chronic NANB hepatitis and 5 of 11 convalescent persons after acute NANB hepatitis had CIC as detected by the Raji cell technique. CIC in chronic NANB hepatitis were composed of IgG, C3, and in 7 of 10 cases also IgM, while in CIC from convalescent persons IgG and C3 were present, too, but IgM was detected in only 1 case. Viral antigens within the CIC were not detectable in any case while 14 of 16 chronic NANB hepatitis patients were found to have free virus-associated antigen in serum.

Antigen-Antibody Complex↗
PubMed1983

[Animal experimental examination of a phase III study on the effect of the combination therapy of bruneomycin, cytostasan and prednisone].

The effectivity of a combined application of Bruneomycin, Cytostasane and Prednisone has been tested in five qualitatively different experimental animal test models. The selected dose levels and the treatment schedule were based on an instruction given in a phase III-study. No effectivity was demonstrable in any of the tumor systems selected neither with the single components, nor with their combination, though the toxicity clearly revealed a dose dependence.

Animals↗
PubMed1983

In vitro characteristics of a human mammary carcinoma 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 showed predominantly simple undifferentiated and also tubular structures. The 5th in vitro passage of these cells were characterized by growth curves, DNA-distribution patterns and chromosome numbers. Cells of the 5th in vitro passage were i.p. transplanted in nude mice. The characteristics of the 21st passage of ascitic cells and solid tumour material grown in nude mice were compared with cell characteristics of the 5th in vitro passage. Our results demonstrate that malignant cells (ascitic) are best able to proliferate in vitro after transplantation into nude mice. The number of polyploid cells are increased in this cell population. DNA-distribution patterns and chromosome numbers show a good correlation. Biological properties of human neoplastic cells are dependent on environmental factors.

Aged↗
PubMed1983

[The spiral ganglion of the rhesus monkey].

Four temporal bones of rhesus monkeys were investigated in respect of composition and morphology of the spiral ganglion cells. Using light and electron microscopic technique two main types of ganglion cells could be distinguished, namely 90% large (type I) and 10% small (type II) cells. Both small and large ganglion cells are surrounded by myelin sheaths: 90% of the large neurons are surrounded by myelin sheaths, whereas only 15% of the small neurons have a myelin sheath. The small neurons are exclusively connected with unmyelinated nerve-endings forming synaptic contact with the cell surface. These nerve endings contain vesicles similar to synaptic vesicles; the cytoplasm of the adjacent small ganglion cells contains dense core vesicles. Similar dense core vesicles are, however, also found in the cytoplasm of the large ganglion cells and in the axoplasm of the corresponding nerve axons. It is only in the cytoplasm of the small ganglion cells that dense bundles of neurofilaments are present. It seems that the nerve endings resembling synapses and contacting the small ganglion cells belong to the efferent, olivo-cochlear spiral bundle.

Animals↗