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Biomedical subjects

G Robinson

Publications and source records attributed to G Robinson.

At least 181 records · Page 10Linked to original sources

Immune response of the draining and distal lymph nodes during the progressive grwoth of a chemically-induced transplantable rat hepatoma.

The immunological and histological changes occurring in the lymph node draining the site of a progressively growing intramuscular tumour (D192A) implant were monitored during a 4-week time course. Cell-mediated cytotoxicity against hepatoma-D192A and 15-day rat embryo cell targets, was detected with cells derived from the draining "lumbar" lymph node 4 days after tumour implantation and persisted up to the 2nd week of tumour growth, decreasing rapidly during the 3rd week. The observed lymph-node anergy demonstrated in cytotoxicity tests correlated with the histological findings, in that an initial marked paracortical (T-dependent) response also declined towards the end of the 3rd week of tumour growth. The B-dependent cortex showed active lymphocyte follicles in the 2nd week of the time course, and plasma-cell production continued until the experiment was terminated. These changes were shown to occur with the progressive increase in lymph-node mass. Serum antibody specific for the developing tumour was detected during the latter stages of tumour growth. The immunological and histological changes displayed were out of phase with those shown by the draining lymph node.

Animals↗

Compliance as a factor effecting the patency of a copolyurethane vascular graft.

A new solid-wall vascular graft which has a compliance approximating that of the natural artery has been prepared from a copolyether-urethane material. Six of nine of these compliant grafts implanted in dogs were patent on removal, the longest implant time being 77 days for a 4-mm I.D. femoral artery graft. This is in contrast to noncompliant grafts of the same copolyurethane in which failure usually occurred within 48 hr.

Animals↗

Informed consent: recall by patients tested postoperatively.

When tested for recall between 4 and 6 months following operation, 20 patients failed to remember accurately major portions of their informed consent interview. Documentation of the details of consent in the clinical record is considered advisable.

Disclosure↗

Immunochemical studies of the endocrine cells of the gastrointestinal tract. I. The use and value of peroxidase-conjugated antibody techniques for the localization of gastrin-containing cells in the human pyloric antrum.

This paper describes and immunochemical localization of gastrin-containing endocrine cells in the human pyloric antrum using antibodies conjugated to horseradish peroxidase. With pre-fixed cryostat sections, a distinct clear-cut staining of gastrin-containing cells can be obtained either by direct or indirect single stain procedures, but may cells containing endogenous peroxidase activity also stain. In order to abolish staining due to endogenous peroxidase, sections were pretreated with a number of inhibitors prior to incubation in immune sera, but the inhibitors used appeared to interfere with the antigenicity of the gastrin molecule since subsequent immunochemical localization was impossible. The application of a double-staining technique, however, allowed us to distinguish easily between those cells which contained endogenous peroxidase and those on to which labelled antibody had been adsorbed. No labelled cells were found in post-fixed cryostat sections of fresh-frozen tissue. The technique is of value because preparations are permanent, a fluorescence microscope is not required, and the same technique can be adapted for use with the electron microscope.

Animals↗

Bypass grafts for recurrent or complex coarctations of the aorta.

Twenty-three patients aged 5 to 53 years with recurrent or complex coarctations of the aorta were successfully operated upon using bypass grafts. This technique of repair was selected for 5 patients with recurrent coarctation, 11 with long-segment coarctation with or without hypoplasia of the transverse aortic arch, and 7 with inadequate collateral circulation. Nineteen patients had bypass grafts from the left subclavian artery to the distal descending thoracic aorta. The other 4 had a combined approach through a left thoractomy and median sternotomy with grafts between the ascending and descending thoracic aorta. All patients survived the operative procedure. One patient were reexplored for a hemothorax and 5 developed transient postoperative hypertension. There were no instances of abdominal vasculitis or lower extremity paralysis. These patients have been followed from 3 months to 11 years postoperatively, and all but 1 are alive and well. Twenty-two are normotensive, and none have the sequelae of hypertensive disease. Gradients up to only 15 mm Hg exist between upper and lower extremity blood pressures. Five patients have undergone postoperative catheterization and aortography, and all have patent grafts. This procedure is a useful and adjunct in difficult coarctations of the aorta and can be safely performed with excellent reproducible long-term results.

Adolescent↗

Immunochemical studies of the endocrine cells of the gastrointestinal tract. II An immunoperoxide technique for the localization of secretin containing cells in human duodenum.

Endocrine cells containing secretin have been identified in the epithelium lining human duodenum by direct and indirect immunoperoxidase techniques using immune sera raised against pur natural secretin. The techniques were applied to sections of carbodiimide-fixed tissue embedded in polyethylene glycol. Some sections, stained by a modified indirect technique, were processed for electron microscopy; secretin-containing granules were present by ultrastructural preservation was too poor to be of value. The potential advantages of a peroxidase technique over fluorescein-coniugated antisera are discussed.

Carbodiimides↗