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T Morris

Publications and source records attributed to T Morris.

119 records · Page 7Linked to original sources
PubMedDate not supplied

Cholesterol metabolism following portacaval shunt in the pig.

Portacaval shunting resulted in lower serum cholesterol and low density lipoprotein levels in comparison with values for littermate control pigs. Triglyceride levels were lower in the shunted animals only while receiving a low fat diet. The reductions in serum cholesterol and triglyceride levels of shunted pigs while receiving a standard pig diet were shown to be related to reduced hepatic synthesis of cholesterol and triglycerides.

Animals↗
PubMedDate not supplied

Reevaluation of plain radiographic findings in the diagnosis of aortic rupture: the role of inspiration and positioning on mediastinal width.

Despite the advent of newer imaging modalities, conventional radiography and clinical examination remain the primary screening method in evaluation of the mediastinum following blunt thoracic trauma. Mediastinal width (MW) is generally considered an important finding in assessing for aortic rupture. The degree of inspiration and patient positioning clearly affects MW, but is largely ignored in the literature. This study investigates the mediastinal widths of normal volunteers with differing degrees of inspiration and positioning, and compares them to radiographs of patients with known aortic ruptures. Mediastinal widths were obtained from chest radiographs of 16 patients with known aortic rupture, and from 50 volunteers using AP-inspiratory-supine, AP-expiratory-supine, and PA-inspiratory-upright technique. Upper 95% confidence limits were obtained for normals. A statistically significant difference in MW of normals was found between inspiratory-supine, expiratory-supine, and upright-inspiratory techniques. Compared to the same degree of inspiration in normals, 12 of 16 patients with aortic rupture had a MW above the upper 95% confidence limits. It is concluded that mediastinal width in normals is significantly affected by the degree of inspiration and positioning. When comparing mediastinal widths for normals and ruptures, there was a significant difference in MW for most degrees of inspiration. As depth of inspiration increased, differences between MW in controls and rupture patients increased. We conclude that patient positioning and degree of inspiration are important factors in assessing the mediastinum, and every effort should thus be made to obtain an upright-inspiratory film if clinically feasible prior to declaring a mediastinum as abnormal.

Adolescent↗
PubMedDate not supplied

The effect of iohexol on glucose metabolism compared with metrizamide.

In a previous in vitro study we demonstrated reduced CO2 production in rat hippocampal tissue when metrizamide was added. This metabolic depression is believed to be a result of the 2-deoxy-D-glucose (2-DG) portion of the metrizamide molecule since 2-DG is a known competitive inhibitor of glucose metabolism. This competitive inhibition probably occurs at the cell membrane since it has never been shown that metrizamide penetrates neural cells. Further the inhibition is most likely related to competition for the membrane glucose carrier. A new nonionic contrast medium, iohexol, does not contain a 2-DG component and if the hypothesis for the metabolic inhibition is valid we should not expect metabolic inhibition with iohexol. This hypothesis was tested using the rat hippocampus model previously used for metrizamide. We compared iohexol with metrizamide in isotonic concentrations and also examined the effect of hypertonicity. These experiments did not demonstrate inhibition of CO2 production with iohexol at near physiologic osmolalities, however, there was a marked depressive effect with increasing osmolality. This effect from hypertonicity is, however, probably of less importance in vivo where water will rapidly diffuse toward the hypertonic areas. The apparent lack of interference of the iohexol molecule on glucose metabolism should therefore make iohexol a more suitable contrast medium, for subarachnoid investigations than metrizamide.

Animals↗