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Biomedical subjects

K Wolf

Publications and source records attributed to K Wolf.

At least 199 records · Page 11Linked to original sources
PubMed1982

Extrachromosomal mutator inducing point mutations and deletions in mitochondrial genome of fission yeast.

We report the isolation and characterization of a mutator mutant in the fission yeast Schizosaccharomyces pombe. This mutator is of extrachromosomal, very likely mitochondrial, inheritance and acts exclusively on mitochondrial mtDNA. It greatly enhances the frequency of spontaneous mitochondrial drug-resistance mutants compared to the wild type, but it is not obligatory for their occurrence. In contrast, mitochondrial respiratory deficient mutants can only be isolated from mutator strains. It could be shown that this mutator induces point mutations as well as deletions in the mitochondrial genome which lead to respiratory deficiency. This mutator might prove to have a novel function encoded by the mtDNA.

Anti-Bacterial Agents↗
PubMed1982

Survival of duck plague virus in water from Lake Andes National Wildlife Refuge, South Dakota.

An isolant of duck plague herpesvirus from the Lake Andes Refuge outbreak was seeded in raw and filter-decontaminated water from two locations on the refuge, held at 4 C, and assayed for infectivity intermittently over a period of 2 mo. From an initial level of about 10(5) PFU per ml, infectivity in the filtered samples uniformly dropped to about 10(4) PFU per ml. Infectivity in the raw samples declined much more rapidly; infectious virus remaining at the end of 2 mo (ca. 10(1) PFU per ml) was only about 0.01% of that originally seeded.

Animals↗
PubMed1981

Synthesis of mitochondrial DNA during the cell cycle of the petite negative yeast Schizosaccharomyces pombe.

Synthesis of mitochondrial DNA (mitDNA) and nuclear DNA (nucDNA) during growth of synchronously dividing cultures of Schizosaccharomyces pombe (S. pombe) was followed by pulse labelling with radioactive adenine and determination of its rate of incorporation into total protoplast DNA and into the DNA of DNase-treated mitochondria at different stages of the cell cycle. It could be demonstrated that both mitDNA and nucDNA were synthesised discontinuously and at different points in the cell cycle.

Ascomycota↗
PubMed1981

Nucleo-cytoplasmic interactions in the petite negative yeast Schizosaccharomyces pombe. Inhibition of nuclear and mitochondrial DNA syntheses in the absence of cytoplasmic protein synthesis.

In the petite positive yeast, Saccharomyces cerevisiae, cycloheximide selectively inhibits protein synthesis on cytoplasmic ribosomes, and, as a consequence, nuclear DNA synthesis. Mitochondrial DNA, however, is synthesized for 4-6 h after cessation of protein synthesis. In this paper we show that in contrast to Saccharomyces cerevisiae, synthesis of mitochondrial and nuclear DNA is tightly coordinated in the petite negative yeast Schizosaccharomyces pombe, since inhibition of cytoplasmic protein synthesis leads immediately to cessation of both nuclear and mitochondrial DNA synthesis.

Ascomycota↗
PubMed1980

Poikilotherm vertebrate cell lines and viruses: a current listing for fishes.

A survey of the literature and of work being done in vertebrate cell culture shows that there are currently in existence and available to investigators some 61 cell lines representing 17 families and 36 species of fish. The literature of fish virology shows that at least 17 fish viruses have been isolated and that at least 15 others have been visualized by electron microscopy. A minimum of four major virus groups--rhabdovirus, orthomyxovirus, iridovirus and herpesvirus--are known from fish. Original references, key reviews and sources of cell lines are given.

Animals↗
PubMed1979

2 micrometer covalently closed non-mitochondrial circular DNA in the petite-negative yeast Schizosaccharomyces pombe.

A population of small covalently closed non-mitochondrial circular DNA molecules was isolated from the petite-negative yeast Schizosaccharomyces pombe. The mean length of these molecules, possessing the same density as nuclear DNA (1.695 g/cm3) is 1.95 +/- 0.18 micrometer. The presence of these minicircles in crude mitochondrial preparations indicates their tight association with mitochondrial particles. Their disappearance after DNase treatment of mitochondria demonstrates their extramitochondrial location.

Ascomycota↗
PubMed1979

Characterization of EV-2, a Virus Isolated from European Eels (Anguilla anguilla) with Stomatopapilloma.

A virus designated EV-2 has been isolated from external tumor tissue and internal organs of European eels (Anguilla anguilla) with stomatopapilloma. It contains RNA and is ether, acid, and temperature labile above 4 degrees C, and concentrated preparations agglutinate chicken and sheep erythrocytes. The addition of actinomycin D during the first 2.75 h of infection inhibits viral replication. As determined in sucrose gradients, the buoyant density of the virus is 1.19 g/cm(3). EV-2 has a moderately pleomorphic spherical morphology; its diameter ranges from 80 to 140 nm. The virion has narrow, regularly spaced surface projections about 10 nm long. Replication in FHM cells at 15 degrees C shows new infectivity appearing at 10 h postinfection and reaching a plateau at 20 h. Cytopathic effects consist of cell fusion, syncytia, and irregularly rounded cell masses. Viral antigen was detected in the cytoplasm of infected cells by specific immunofluorescence.

Journal Article↗
PubMed1979

Source of referral as an indicator of motivational factors and treatment outcome with drug-dependent clients.

Source of referral to substance abuse treatment agencies was investigated as a potential indicator of client motivation and treatment outcome. Clients referred by nine different sources were compared in terms of length of stay in treatment, drug use status at termination, and closing evaluation. There were no differences between the nine referral sources in terms of the frequency with which clients were rated as improved, no improvement, or recovered. However, there were significant differences between referral sources and length of time in treatment. Clients referred by their families or those who had prior institutional experience remained in treatment longer than other groups. Length of stay in treatment was related to drug use status at termination. Clients who had detoxified remained in treatment significantly longer than clients who had not detoxified. It may be that a social support system (family) and experience in a structured setting (prior institutional experience) facilitate positive treatment outcomes.

Humans↗
PubMed1979

[Diameter of coronary arteries before and after bypass grafting (author's transl)].

Patients with patent coronary bypass grafts showed the followings: 1. a decrease in prestenotic coronary diameter due to a reduction in flow. 2. An increase of the poststenotic segment of the bypassed vessel due to an increase in flow via the venous graft. 3. An increase of the bypassed stenosis, mainly due to a general decrease of vessel diameter proximal to the stenosis. 4. No change in diameter in non bypassed arteries. The postoperative changes in diameter were not dependent on the time elapsed since surgery and were independent from the severity of coronary sclerosis and the number of risk factors. A correlation was found between the amount of the diameter changes and the amount of reduction in exercise induced ST-segment depression. The decrease in coronary diameter proximal to the stenosis is not due to progression of coronary sclerosis but to a functional change. A narrow poststenotic vessel does not constitute a contraindication for bypass grafting because its true diameter is flow dependent and cannot be judged with certainty from the preoperative angiogram.

Coronary Angiography↗