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Biomedical subjects

R A Collins

Publications and source records attributed to R A Collins.

120 records · Page 7Linked to original sources
PubMed1976

The function of mitochondrial genes in Neurospora crassa.

The 18 extranuclear mutants of Neurospora crassa, without exception, have abnormal mitochondrial respiratory systems. On the basis of genetic, phenotypic and physiological criteria, these mutants are divided into four groups: 1) the cytochrome aa3 and b deficient "poky" variants that are defective in mitochondrial ribosomes assembly, 2) the cytochrome aa3 deficient mutants, [mi-3] and [exn-5], that appear to have genetic lesions affecting a component of a regulatory system controlling cytochrome aa3 synthesis, 3) the cytochrome aa3 and b deficient "stopper" mutants with physiological lesions that probably affect mitochondrial protein synthesis, and 4) cni-3, a mutant that is constitutive for an inducible mitochondrial cyanide-insensitive oxidase in spite of having a normal cytochrome mediated electron-transport system. It is proposed that the mitochondrial genophore not only codes for cellular components that are essential for the formation of the mitochondrial protein synthesizing apparatus, but also for components of a regulatory system that coordinates the expression of nuclear and mitochondrial genes during the biogenesis of the mitochondrial electorn-transport system.

Adenosine Triphosphatases↗
PubMedDate not supplied

Cytokine expression in pulmonary and peripheral blood mononuclear cells from calves infected with bovine respiratory syncytial virus.

The possible involvement of cytokines in the acute viral pneumonia induced by respiratory syncytial virus (RSV) infection was studied in calves. The patterns of cytokine mRNA expression in mononuclear cells (MNC) isolated from the lung and peripheral blood of six gnotobiotic calves infected seven days previously with bovine RSV were analysed by reverse-transcription polymerase chain reaction using primers specific for bovine cytokines. The pattern of cytokines detected indicated a mixed type of response to RSV infection as mRNAs for IFN-gamma, IL-2, IL-4 and IL-10 were detected in pulmonary and peripheral blood MNC from calves with extensive pneumonic consolidation. In contrast, only mRNA for IFN-gamma was detected in MNC from the lungs and peripheral blood of uninfected animals. These data provide preliminary information on the potential range of cytokines produced in calves following infection with bovine RS virus.

Animals↗
PubMedDate not supplied

The pathology of post-parturient fatty liver in high-yielding dairy cows.

The pathology of post-parturient fatty liver has been studied in a group of 20 high-yielding dairy cows; 10 had less than 20 per cent fat in the liver cell and were classified as having a mild fatty liver and 10 had more than 30 per cent fat in the liver cell and were classified as having severe fatty liver. Severe fatty liver was accompanied by a number of morphological changes including the occurrence of lipogranulomas, increased liver cell volume, decreased volume of rough endoplasmic reticulum per liver cell and evidence of mitochondrial damage. The latter two changes were reflected in reduced albumin levels and increased activities of mitochondrial enzymes observed in the blood of cows with severe fatty liver. Reduced fertility may be one of the consequences of severe fatty liver in the dairy cow.

Animals↗