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O Meyer

Publications and source records attributed to O Meyer.

10 recordsLinked to original sources

[Serum and articular immune complexes detection by the antibody-dependent cytotoxicity inhibition reaction in inflammatory rheumatological conditions and connective tissue disorders (author's transl)].

Detection of circulating and intra-articular soluble immune complexes, has been done in 28 rheumatoid arthritis, 8 mixed connective tissue diseases and 8 other connective tissue diseases. The method used, is based on a competition reaction in the antibody dependent lymphocytotoxicity reaction (ADC). In rheumatoid arthritis serum immune complexes were detected in 75% of the seropositive cases and 66% of the seronegative ones. The mean level of complexes is higher in the former form of the disease. In a given patient, the concentration of immune complexes in joint fluid, is higher than in serum. Immune complexes were present in the serum of 75% of patients with mixed connective tissue disease, but, here, at a concentration lower than in rheumatoid arthritis and systemic lupus erythematosus. It is proposed that measurement of serum immune complexes, can also be an interesting parameter in the follow-up of the patients.

Antibody-Dependent Cell Cytotoxicity

Oxidation of carbon monoxide in cell extracts of Pseudomonas carboxydovorans.

Extracts of aerobically, CO-autotrophically grown cells of Pseudomonas carboxydovorans were shown to catalyze the oxidation of CO to CO(2) in the presence of methylene blue, pyocyanine, thionine, phenazine methosulfate, or toluylene blue under strictly anaerobic conditions. Viologen dyes and NAD(P)(+) were ineffective as electron acceptors. The same extracts catalyzed the oxidation of formate and of hydrogen gas; the spectrum of electron acceptors was identical for the three substrates, CO, formate, and H(2). The CO- and the formate-oxidizing activities were found to be soluble enzymes, whereas hydrogenase was membrane bound exclusively. The rates of oxidation of CO, formate, and H(2) were measured spectrophotometrically following the reduction of methylene blue. The rate of carbon monoxide oxidation followed simple Michaelis-Menten kinetics; the apparent K(m) for CO was 45 muM. The reaction rate was maximal at pH 7.0, and the temperature dependence followed the Arrhenius equation with an activation energy (DeltaH(0)) of 35.9 kJ/mol (8.6 kcal/mol). Neither free formate nor hydrogen gas is an intermediate of the CO oxidation reaction. This conclusion is based on the differential sensitivity of the activities of formate dehydrogenase, hydrogenase, and CO dehydrogenase to heat, hypophosphite, chlorate, cyanide, azide, and fluoride as well as on the failure to trap free formate or hydrogen gas in coupled optical assays. These results support the following equation for CO oxidation in P. carboxydovorans: CO + H(2)O --> CO(2) + 2 H(+) + 2e(-) The CO-oxidizing activity of P. carboxydovorans differed from that of Clostridium pasteurianum by not reducing viologen dyes and by a pH optimum curve that did not show an inflection point.

Aldehyde Oxidoreductases

Detection of soluble immune complexes by the technique of ADCC inhibition in human diseases.

Soluble immune complexes were detected using inhibition of antibody-dependent cell-mediated cytotoxicity (ADCC) in sera of patients with various diseases. Results were positive in 32/41 patients with rheumatoid arthritis (78%), in 27/38 systemic lupus erythematosus patients (71%), in 7/10 cutaneous lupus erythematosus patients (70%), in 6/8 mixed connective tissue disease patients (75%), in 11/26 membranous glomerulonephritis patients (42%), in 6/20 membranoproliferative glomerulonephritis patients (30%) and in 3/12 multiple sclerosis patients (25%). ADCC inhibition was compared with PEG precipitation technique and was found to be more sensitive for detecting soluble immune complexes. Various pitfalls are discussed.

Animals

Influence of diet and strain of rat on kidney damage observed in toxicity studies.

The laboratory animal is susceptible to biological variation due to a variety of causes. Thus genetic variation and nutrition have become recognized to influence the reaction of the animal to experimental procedures. Severe kidney injury was observed at our institute in preliminary studies with 1% butylated hydroxytoluene (BHT) incorporated in a semisynthetic diet fed to Wistar rats for one month. These lesions together with nephrocalcinosis, a common finding in rats fed a semisynthetic diet might suggest that the animals in our experiment were predisposed to kidney damage. In order to show the influence of the rat strain and the type of diet a study was performed with both Wistar and Sprague-Dawley rats fed a semisynthetic or commercial diet mixed with 1% BHT. It was observed that the semisynthetic diet had a marked effect on the severity of the kidney lesions and that the lesions were independent of the rat strain used. In addition, an apparent sex variation was found.

Animal Feed

Reisolation of the carbon monoxide utilizing hydrogen bacterium Pseudomonas carboxydovorans (Kistner) comb. nov.

From enrichment cultures four carbon monoxide utilizing bacteria were isolated; strain OM5 isolated from waste water was studied in detail. The cells are Gram-negative, slightly curved rods, motile by a single subpolarly inserted flagellum. The colonies are smooth, translucent and not slimy. The cells are able to grow autotrophically in mineral medium under an atmosphere of 40% CO, 5% O2 and 55% N2 at a doubling time of 20h (30 degrees C) or of 85% H2, 5% O2 and 10% CO2 at a doubling time of 7h. Heterotrophic growth occurred on organic acids such as acetate(td = 8h), pyruvate(td = 8h), lactate, crotonate, malate, succinate (td = 8h), formate (td = 35h) and glyoxylate as substrates. The enzyme system for carbon monoxide utilization is formed only during growth on CO; hydrogenase is present in cells grown on CO or on H2 + CO2 as well as grown on pyruvate. The rate of oxygen reduction by intact CO-grown cells is 3.7-fold higher in the presence of hydrogen than in the presence of carbon monoxide. During growth the stoichiometry of gas uptake was 6.1 CO + 2.8 O2 + H2O leads to CH2O +5.1 CO2. For the new isolate the name Pseudomonas carboxydovorans (Kistner) comb. nov. has been proposed.

Carbon Monoxide

A study of the teratogenicity of butylated hydroxyanisole on rabbits.

A teratogenicity study on butylated hydroxyanisole (BHA) was carried out in SPF New Zealand White rabbits. BHA was given by gavage from day 7--18 of the gestation period in doses of 0, 50, 200 and 400 mg/kg body wt./day. The fetuses were removed on day 28. No effect related to the treatment with BHA was observed on the number of corpora luteae, implantations, fetuses dead or alive, or on gross malformations, skeletal and internal malformations, and on the weight of the fetuses.

Abnormalities, Drug-Induced

[Juvenile arthritis reevaluated in rheumatology in adult age. 30 cases].

The authors describe and comment on 30 observations of peripheral polyarthritis starting before puberty and reveluated in an adult rheumatologoy service at the average age of 29 and during an observation period of about 16 years. The actual classification of juvenile polyarthritis proves to be valid in this group since the clinical forms are still observed in adulthood. However, during the evolution, there is a shifting from one form to another. The systemic forms can reoccur in adulthood even after several years of quiescence, accompanied by visceral complications. The pauciarticular forms as a rule remain benign. As in childhood, they frequently show antinuclear factors. Some forms, initially peripheral, can show axial signs. The presence of HLA B27 antigens allow them to be linked up with ankylosing spondylarthritis. But this is not the case for all the forms with sacroiliac functions. The evolution since childhood is often characterized by long remissions which can still persist by the time of the visit, which is then motivated by resulting mechanical and local arthrotic problems. Despite often severe anatomical symptoms, the functional handicap is limited, allowing quite a remarkable adaptation. Most of the patients lead an active professional life. Yet despite this and despite an often satisfactory sex life, half of the patients have a psychological handicap which makes it necessary for them to be placed under special carl. No therapeutic conclusion, particularly about the efficiency of the basic therapy, can be drawn from this study.

Adult

[Dominant generalized cortical hyperostosis with multiple involvement of the cranial nerves].

The authors report an observation of dominant generalized cortical hyperostosis with multiple and unilateral involvement of a certain number of cranial nerves. In other members of the family, who present with the same bone disorder, involvement of the cranial nerves was limited to the facial nerve, either uni or bilaterally, with a partially or totally regressive evolution. This cranial nerve involvement, which is classic in the recessive form (first described) of generalized cortical hyperostosis, has until now, never been reported in the dominant form of this disorder.

Adult