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Biomedical subjects

A R Cooke

Publications and source records attributed to A R Cooke.

At least 55 records · Page 3Linked to original sources
PubMed1974

Effect of several drugs on gastric potential difference in man.

Measurement of gastric mucosal potential difference was used to study the effect on the gastric mucosal barrier in six volunteer subjects of several drugs known to provoke ulcers. Potential differences were also recorded in nine patients with rheumatoid arthritis being treated with long-term aspirin and five patients on long-term prednisone. Unbuffered aspirin and ethanol "broke" the barrier as shown by a rapid fall in potential difference. The effects of aspirin were dose related, with 600 mg causing a greater reduction than 300 mg. The effects of aspirin and ethanol given together were additive and caused the greatest fall in potential difference. Sodium acetylsalicylate did not alter the normal potential difference. Indomethacin, phenylbutazone, and prednisone all failed to cause any change in potential difference. The patients on long-term aspirin and prednisone had readings within the normal range and responded the same as normal subjects to an acute challenge. These studies show that aspirin and ethanol will damage the gastric mucosal barrier but that indomethacin, phenylbutazone, and prednisone do not.

Adult↗
PubMed1974

An inhibitory innervation at the gastroduodenal junction.

Transverse muscle strips, 2-mm wide, were cut serially from the gastroduodenal junction in opossums, cats, dogs, and man. Electrical field stimulation with trains of rectangular current pulses of 0.5 ms in all opossums, all cats, some dogs, and the one human specimen induced relaxation in strips from the thickened circular muscle proximal to the mucosal junction. In some opossums weak relaxations also occurred in the first few strips below the mucosal junction. All other strips contracted or showed no response. This relaxation in opossums was abolished by tetrodotoxin but was not affected by antagonists to adrenergic and cholinergic transmission, nor by tripelennamine, methysergide, pentagastrin, secretin, cerulein, or cholecystokinin. Optimal frequency for stimulus-relaxation was 12 Hz. Chronaxie was 0.85 ms. The junctional strips also showed greater resistances to stretch than those remote from the junction. With apparent species variations, the junctional muscle possesses a nonadrenergic inhibitory innervation which is either absent or unexpressed in adjacent muscle of stomach and duodenum. This suggests the existence of a distinctive inhibitory neural control mechanism for pyloric muscle.

Adrenergic alpha-Antagonists↗
PubMed1974

Seroepidemiology of Congo virus (related to the virus of Crimean haemorrhagic fever) in Nigeria.

A survey for neutralizing antibodies to Congo virus was carried out in Nigeria. Of a total sample population of 250, comprising 141 males and 109 females, 9 males and 15 females had antibody levels >/= 1.5 log neutralization index. In the age group 0-10 years 4 of 84 males and 14 of 79 females had antibody levels >/= 1.5 log neutralization index. There was no evidence of nonspecific antiviral activity in the sera tested.

Adult↗
PubMed1974

Laboratory and clinical investigation of the 1974 influenza epidemic in Nigeria.

Altogether 13 strains of virus were isolated during the 1974 influenza epidemic in Nigeria. These A/Nigeria/1/74 strains were shown by haemagglutination-inhibition tests to be closely related to the A/Port Chalmers/1/73 virus. Antibody to the epidemic strains developed rapidly in the population and 80-95% of all age groups tested possessed high antibody levels; of 145 paired sera tested, 133 (92%) showed sero-conversion to A/Nigeria/1/74 virus.

Adolescent↗