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Biomedical subjects

R Cummins

Publications and source records attributed to R Cummins.

22 records · Page 2Linked to original sources
PubMed1983

Protoporphyrinogen oxidase and ferrochelatase in porphyria variegata.

Protoporphyrinogen oxidase activity and ferrochelatase activity were measured in leucocytes from patients with porphyria variegata. The mean activity of protoporphyrinogen oxidase (PPO) in porphyria variegata (PV) was about 50% of normal (P less than 0.05). The mean activity of ferrochelatase with 59Fe2+ sulphate and protoporphyrin as substrates (in the presence of ascorbic acid) was reduced by 40% (P less than 0.009). The mean activity of ferrochelatase with 59Fe3+ chloride and protoporphyrin as substrates (in the presence of reduced glutathione) was increased by 65% (P less than 0.005). Both are statistically highly significant. The findings are interpreted as follows: (a) The occurrence of a low level of protoporphyrinogen oxidase in PV is confirmed. (b) The findings indicate a concurrent structural change in ferrochelatase (this may be structurally related to (a) but no evidence of this is at present available).

Adult↗
PubMed1982

A new flexible sigmoidoscope for the generalist.

The control of colorectal cancer has become increasingly important because of its high incidence in the United States of more than 115,000 cases annually. Although 50% of neoplastic lesions of the colon arise in the distal 25 cm of the bowel, endoscopic examination of this area has not been generally accepted. Recent studies with flexible sigmoidoscopes as substitutes for the rigid proctosigmoidoscope, primarily by endoscopists, have shown an increased yield of neoplastic lesions, with excellent patient acceptance. This study reports the development of an initial trial in 200 patients with a 30-cm flexible sigmoidoscope designed mainly for the nonendoscopist general physician for routine office use as a substitute for the rigid proctosigmoidoscope. The instrument provided an excellent examination in minimum time and with good patient and physician acceptance. Widespread application of such instruments by generalists in routine office practice could have a significant impact on the control of colorectal cancer.

Adult↗