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Biomedical subjects

W J Wall

Publications and source records attributed to W J Wall.

At least 73 records · Page 4Linked to original sources

Structural complexity of Y chromosome heterochromatin.

Following a standard C-banding procedure early metaphase chromosomes demonstrate a discontinuous distribution of heterochromatin in the long arm of the human Y chromosome. The discrete blocks of heterochromatin can be shown to be separated into nonrepeating sequences by in situ hybridization using probe pHY 2.1. The number of heterochromatin blocks vary from person to person.

Chromosome Banding↗

Liver transplantation without venous bypass.

Fifty consecutive orthotopic liver transplants were performed without venous bypass in 41 recipients. Seven patients were transplanted twice and one patient received 3 transplants. The average age of the recipients was 37 years. The commonest indications for transplantation were primary biliary cirrhosis and cirrhosis from chronic active hepatitis. Fifty-eight percent of the recipients had undergone previous upper abdominal surgery. During the anhepatic period systolic blood pressure decreased by 21% to an average of 98 mm. of mercury. Cardiac output decreased by 52% to a mean (+/- SEM) of 3.89 +/- 0.21 L/min., and there was a doubling of the systemic vascular resistance. The hemodynamic alterations promptly returned to preclamping levels following hepatic revascularization. The average intraoperative transfusion requirements were 13 units of packed red blood cells, 9.6 units of platelets, 14.5 units of plasma and 6.6 L of crystalloid. Patients with previous surgery and retransplants required an average of 13 and 17 units of packed red blood cells, respectively. There was no deterioration in renal function in the postoperative period and no patient required hemodialysis. The 30 day survival was 87.8%. The 90-day and one-year actuarial survival is 80.5% and 68.8%, respectively. It is concluded that venous bypass is not necessary as a routine in orthotopic liver transplantation.

Adolescent↗

A new interstitial deletion of chromosome No. 4 del(4) (q22::q25).

A female child is described with multiple anomalies including epicanthus, frontal bossing, short sternum, polydactyly, cleft of the larynx, renal cysts, and unusual dermatoglyphics. She died aged 3 months and was found to have a unique de novo deletion of chromosome No. 4 (q22-q25). This case is compared with other long arm deletions of 4q and reference made to assignment of genetic markers to chromosome No. 4.

Abnormalities, Multiple↗

Automatic analysis of G-banded human chromosomes by fast scanning microscope photometry. 2. Practical applications.

The practical applications and improvements to a fast scanning microscope photometer system are described. The production of a density profile is demonstrated which, when taken in conjunction with the chromosome scan, allows more information to be extracted from the data than was previously possible. This enables a more accurate correlation to be made between phenotype and karyotype. The system is demonstrated on preparations of known cytogenetically abnormal individuals, showing the range of problems which can be tackled.

Adult↗

Radiologic assessment of bile duct complications in liver transplantation: initial experience.

Four of the first 24 patients who received 31 orthotopic liver transplantations in our institution developed complications at the site of the surgical anastomosis in the common bile duct. There was one anastomotic stricture, one anastomotic stricture with "bile sludge" deposition, and two cases of bile sludge formation without stricturing at the anastomotic site. The two cases of stricturing required surgical revision while both those of bile sludge accumulation without stricture were successfully managed conservatively. Familiarity with the postoperative appearance of the common bile duct anastomosis and its complications is necessary for the proper assessment of these patients.

Adolescent↗

Pleural effusion following liver transplantation.

The postoperative chest radiographs of 11 patients who underwent 14 orthotopic liver transplantations were reviewed. Pleural effusions occurred on the right side in all patients and on the left side in four. The effusions were unrelated to primary cardiovascular disease and usually asymptomatic. They were transudates and resolved spontaneously.

Adolescent↗

Liver transplantation: the initial experience of a Canadian centre.

At the University Hospital in London, Ont., 19 patients have received 24 liver transplants. The commonest indications for transplantation were primary biliary cirrhosis and cirrhosis from chronic active hepatitis. The first three patients in the series died of infectious complications. Eleven of the subsequent 16 recipients are alive from 5 months to 2 1/2 years after transplantation. Eight patients who are alive more than 1 year after the operation have an excellent quality of life. Cyclosporine and steroids in combination are used for immunosuppression. With current surgical techniques, modern immunosuppression and good patient selection, the restoration of patients with advanced irreversible liver disease to good health by liver transplantation is a realistic goal. Much effort and considerable resources are required to run a liver transplant program.

Adolescent↗

Computed tomography in pelvic liposarcoma: a case report.

A case of well-differentiated pelvic liposarcoma with unusual presentation of low-back pain and sciatica, due to the herniation through the greater sciatic notch, is described. Computed tomography is invaluable, not only in predicting the histologic diagnosis, but also in outlining the location, extent, and size of the tumor. This allows accurate planning of the surgical approach.

Back Pain↗

Automatic analysis of G-banded human chromosomes by fast scanning microscope photometry. I. Basic principles and computer control.

A high resolution scanning microscope photometry system has been developed for use with standard G-banded chromosome preparations. Various alternative scanning methods and their limitations are reviewed. The computer algorithms which we use are described for the manipulation of the digitized image as produced by the microscope photometer; these include noise reduction and contrast enhancement as well as altering the orientation of the chromosome.

Chromosome Banding↗

Immunological and pharmacological monitoring in the clinical use of cyclosporin A.

Immunological reactivity to donor antigens and serum concentrations of cyclosporin A were monitored in six patients after renal transplantation. At concentrations of 0.1--1.0 microgram/ml cyclosporin A prevented both donor-specific immune reactivity and clinical rejection during the early post-transplant course. Measurement of cyclosporin A levels and immunological indices allowed individual adjustment of the dosage so as to give excellent early graft function with few adverse effects.

Cyclosporins↗

Tolerance of the liver to ischemia: an experimental study.

The experiments described in this study challenge the 20th century belief that the liver is particularly vulnerable to deprivation of its blood supply for appreciable periods of time. The authors studied the effects of 60 minutes of normothermic hepatic ischemia on 10 pigs. The hepatic artery and its collateral vessels were occluded and portal blood was diverted by a portojugular shunt. This produced a 90% reduction in liver blood flow as determined by xenon-127 washout. None of the animals died of liver failure. The ischemic insult did not produce jaundice in any of the animals and only minimal transient changes in liver enzymes occurred. The results suggest that the liver is capable of withstanding prolonged periods of ischemia.

Alanine Transaminase↗

Skeletal changes in Refsum's disease.

Refsum's disease is a rare inherited disease of lipid metabolism. The cardinal diagnostic features include polyneuritis, cerebellar ataxia, an atypical pigmentosa and a high CSF protein. The disorders is accompanied by the accumulation in the tissues, especially the liver and kidneys, of the lipid 'phytanic acid'. The disease is due to the absence of the enzyme phytanic acid alpha-hydroxylase which catalyses the conversion of phytanic acid to alpha-hydroxy phytanic acid the initial step in its further metabolism. In his original monograph Refsum (1945) documented a number of skeletal abnormalities and the full spectrum of changes that occur has become clear though the accumulating subsequent reports. This paper documents the osseous changes in three members with the disease in a single family. These include epiphyseal dysplasia, especially pronounced in the knees, and shortening and deformity of many of the tubular bones in the hands and feet.

Adult↗