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R B Gordon

Publications and source records attributed to R B Gordon.

75 records · Page 5Linked to original sources

Computed tomography of the abnormal appendix.

This report describes the CT features of 29 abnormal appendices visualized during abdominal CT examinations. There were 22 cases of acute appendicitis, five mucoceles, and two mucinous adenocarcinomas of the appendix. The inflammed appendix appeared either as a fluid-filled slightly distended structure or as a collapsed small tubular structure. It was visualized on either cross or longitudinal sections and showed slight circumferential wall thickening. Periappendiceal inflammation was detected in 19 cases and intraluminal appendicoliths in six cases. Mucocele appeared as a larger fluid-filled round, oval, or tubular structure having a thin, sharp wall, low density contents, and no periappendiceal inflammation. Mucinous carcinoma appeared either as a single or as multiloculated, irregular shaped cystic lesion with solid elements. Infiltration of cecum and terminal ileum was seen in one case. In five cases the abnormal appendix was not recognized initially and was identified only after repeat 5 X 5 mm sections were obtained. During CT examination, demonstration of an abnormal appendix establishes the source of the abdominal pathology and helps greatly in the differential diagnosis.

Acute Disease↗

Characterisation of five missense mutations in the cystathionine beta-synthase gene from three patients with B6-nonresponsive homocystinuria.

Homocystinuria, due to a deficiency of the enzyme cystathionine beta-synthase (CBS), is an inborn error of sulphur-amino acid metabolism. This is an autosomal recessive disease which results in hyperhomocysteinaemia and a wide range of clinical features, including optic lens dislocation, mental retardation, skeletal abnormalities and premature thrombotic events. We report the identification of 5 missense mutations in the protein-coding region of the CBS gene from 3 patients with pyridoxine-nonresponsive homocystinuria. Reverse-transcription PCR was used to amplify CBS cDNA from each patient and the coding region was analysed by direct sequencing. The mutations detected included 3 novel (1058C-->T, 992C-->A and 1316G-->A) and 2 previously identified (430G-->A and 833C-->T) base alterations in the CBS cDNA. Each of these mutations predicts a single amino acid substitution in the CBS polypeptide. Appropriate cassettes of patient CBS cDNA, containing each of the above defined mutations, were used to replace the corresponding cassettes of normal CBS cDNA sequence within the bacterial expression vector pT7-7. These recombinant mutant and normal CBS constructs were expressed in Escherichia coli cells and the catalytic activities of the mutant proteins were compared with normal. All of the mutant proteins exhibited decreased catalytic activity in vitro, which confirmed the association between the individual mutation and CBS dysfunction in each patient.

Adolescent↗