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Biomedical subjects

C Blackburn

Publications and source records attributed to C Blackburn.

22 records · Page 2Linked to original sources

DNA synthesis and template activity in a mutant of polyoma virus with altered expression of late viral proteins.

The 3049 strain of polyoma virus overproduces late RNA and proteins. The synthesis and accumulation of virus DNA was measured in cells infected with 3049 and a wild-type virus, lpS, to assess the possible role of gene dosage in this phenomenon. The rate of incorporation of [3H]thymidine into the DNA of 3049 and lpS virus was shown to be identical. The number of genome copies per cell, determined by DNA-DNA reassociation kinetics, was found to be similar in either whole cell or Hirt extracts of cells infected with the two viruses. Viral transcription complexes were isolated by Sarkosyl extraction, and the specific transcriptional activity was measured by incorporation of [3H]UTP. The incorporation of [3H]UTP and the DNA content of transcription complexes were indistinguishable. These results suggest that overproduction of late RNA (and protein) by the 3049 virus is not due to either an increased number of viral genomes per cell or an increased fraction of genomes involved in transcription. These and other data (unpublished) support the conclusion that the altered phenotype is due to a posttranscriptional mechanism.

Animals↗

Effects of breathing retraining in patients with chronic obstructive pulmonary disease.

Subjects with severe chronic obstructive pulmonary disease (COPD) were studied to evaluate the effects of breathing retraining (BRT) on exercise tolerance. Twenty-two subjects exercised on a treadmill three times weekly for six weeks. Twelve of the subjects (controls) then exercised for three more weeks; the other ten subjects received three more weeks of exercise reconditioning plus BRT. Results of routine pulmonary function and exercise tests were similar in both groups at the beginning of the study and after six weeks of exercise. However, in the last three weeks of the study, increments in exercise performance were significantly greater in the BRT subjects than in controls (P less than .002). Following BRT, respiratory rate during exercise decreased (P less than .005) and tidal volume and PaO2 during exercise increased (P less than .05). Thus, these data suggest that BRT increases exercise performance in subjects with severe COPD.

Breathing Exercises↗

Low income, inequality and health promotion.

Drawing on reports and statistics that demonstrate the link between health and low income, this article explains how low income can act as a key health hazard and set off a domino effect involving other health hazards such as substandard housing, pollution and poor social support systems. The author argues that we have still some way to go to put a poverty perspective on strategies to promote positive health.

Health Promotion↗