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D F Du Toit

Publications and source records attributed to D F Du Toit.

54 records · Page 3Linked to original sources
PubMed1982

Effect of cyclosporin A on allotransplanted pancreatic fragments to the spleen of totally pancreatectomized dogs.

Cyclosporin A (Cy A) was evaluated in dogs to assess its effectiveness of prolonging survival of allogeneic pancreatic islet tissue transplanted to the spleens of totally pancreatectomized mongrel dogs. Thirty-seven dogs were made diabetic by total pancreatectomy. Ten untreated pancreatectomized animals survived a mean (+/-SE) of 6.3 +/- 0.9 days and died with mean (+/-SE) plasma glucose levels of 23.2 +/- 2.7 mmol/liter. Dispersed pancreatic fragments, prepared by collagenase digestion without separation of exocrine and endocrine components, were directly implanted into the splenic pulp of 27 pancreatectomized dogs. Twelve dogs given autotransplants became normoglycemic after 4.3 +/- 0.5 days and remained so until killed at 60 days post-transplant, although normal glucose tolerance tests were not achieved. Eight nonimmunosuppressed dogs given allogeneic pancreatic fragments did not become normoglycemic but survived for 13.0 +/- 2.1 days, the dogs dying with a terminal plasma glucose of 22.7 mmol/liter. An additional seven dogs given allogeneic transplants were given Cy A (oral solution), 25 mg/kg/day, for 14 days, and, although failing to become normoglycemic, survived for 28.1 +/- 5.4 days and died with terminal plasma glucose levels of 25.1 +/- 0.6 mmol/liter. Intrasplenic complications included subcapsular hematomas, intrasplenic necrosis and cavitation, capsular perforations, and arteriolar thrombosis. The failure to achieve normoglycemia with allogeneic dispersed pancreatic tissue in dogs treated with Cy A and the complications associated with the implantation of the tissue in the spleen do not suggest that this approach is worthy of clinical trial.

Animals↗
PubMed1982

Prolongation of segmental pancreatic allografts in dogs receiving cyclosporin A.

This study showed that a heterotopic autotransplant of the tail of the pancreas was capable of maintaining adequate glucoregulatory function in pancreatectomized dogs, glucose tolerance test curves, and K values not differing from normal dogs 4 months after transplantation. Hyperinsulinemia in the fasting state was observed in the absence of hypoglycemia in autograft and allograft recipients. Intraductal Ethibloc injection produced total replacement of the exocrine gland at 4 months by fibrosis but with the preservation of islets. Cyclosporin A (Cy A, oral drinking solution) in a dose of 25 mg/kg/day given to recipients of heterotopic segmental allografts produced a slight but significant prolongation of graft survival, but a dose of 40 mg/kg/day resulted in indefinite graft survival (greater than 100 days) in five of eight allograft recipients. During intravenous glucose tolerance tests (IVGTTs), fasting hyperinsulinemia and significantly impaired glucose degradation (K values) was observed in long-term surviving allograft recipients 4 months after transplantation. In four long-term surviving pancreatic allograft recipients initially given 40 mg/kg/day, the dose of Cy A was gradually reduced after 4 months to a maintenance dose of 5 mg/kg/day by 6 months. On a dose of 5 mg/kg/day, three dogs rejected their grafts between 18 and 28 days after this schedule had commenced. Successful reversal of the hyperglycemia in two of three dogs that rejected their grafts was achieved by i.v. methylprednisolone and increased doses of Cy A. These results indicate that Cy A alone could significantly prolong the survival of canine pancreatic segmental allografts, but initially higher doses were required than that found to be effective in prolonging renal allograft survival in the dog.

Amylases↗
PubMed1981

Canine intestinal intussusception following renal and pancreatic transplantation.

In 138 mongrel dogs given renal transplants, 10 developed postoperative intussusceptions. The sites were jejunojejunal (seven), ileo-ileal (two) and ileocolic (one). In 30 puppies given intrasplenic autografts of dispersed pancreatic fragments after total pancreatectomy, five developed jejunojejunal intussusceptions. Presenting signs included vomiting, failure to eat, periodic attacks of pain, straining with the passage of bloodstained mucous, dehydration, weight loss, abdominal wall rigidity and an abdominal mass. The majority of dogs presented within the first seven days following transplantation, occasionally as late as the third week. Early operative intervention was essential to save the dogs and at laparotomy eight of nine intussusceptions were successfully reduced manually; one small bowel resection was performed for irreducibility. Recurrence was not observed in this series but reoperation in the puppies was invariably fatal. Factors contributing to the development of intussusception in the puppies included round worm infestation, recent dietary change following weaning, malabsorption and diarrhoea due to pancreatic insufficiency following pancreatectomy and respiratory infections suggesting an infective origin for the intussusceptions.

Animals↗
PubMed1981

A technique for transplanting pancreatic islets as a vascularized graft and prevention of rejection with cyclosporin A.

Transplants of isolated allogeneic pancreatic islets behave as if extremely immunogenic but vascularized segmental pancreatic allografts do not evoke such a rapid rejection of islet tissue. We have transplanted rat pancreatic islets as a vascularized graft by implanting isolated islets under the renal capsule of a syngeneic diabetic rat and, after successful reversal of diabetes, a composite graft of kidney and islets was transplanted into an allogeneic diabetic host. Cyclosporin A was used to suppress rejection of the allografts in doses that have previously been shown to completely suppress rejection of renal allografts and delay rejection of vascularized segmental pancreatic allografts. This strategy produced indefinite survival of the allogeneic isolated pancreatic islets.

Animals↗
PubMed1979

[Carcinoid tumour of the stomach].

Carcinoid tumours are not common, but have been found along the digestive tract and at other sites in the body. The carcinoid syndrome is associated with some of these tumours. A case of gastric carcinoid, without the syndrome, is discussed, and a review of the biochemistry involved and the treatment is given.

Aged↗
PubMed1979

Lesser curve necrosis following proximal cell vagotomy for gastric ulcer. A case report.

A case of avascular necrosis of the lesser curve of the stomach following a highly selective vagotomy (HSV) for a gastric ulcer is reported. It is fortunately rare, but is a frightening complication. The necrosis, which is presumably ischaemic in origin, is caused by total devascularization of the lesser curvature of the stomach. The complication is usually diagnosed late and has a considerable mortality.

Aged↗
PubMed1979

Unusual presentation of choriocarcinoma. A case report.

We report the management of a case of malignant trophoblastic disease which presented initially as a haematemesis and melaena from a gastric metastasis. The patient had had a tubal sterilization 4 years previously. The management of trophoblastic disease in general is also discussed, and the importance of chemotherapy is stressed.

Adult↗
PubMed1977

Bile peritonitis and miliary tuberculosis: a case report.

We report an unusual case of bile peritonitis in a child. The literature on bile peritonitis is reviewed, and its treatment is discussed. According to the literature, bile peritonitis has a good prognosis provided operation is early. Patients in whom bile is septic at the time of surgery have an increased morbidity and a considerable mortality.

Bile↗
PubMedDate not supplied

EVAR: critical applied aortic morphology relevant to type-II endoleaks following device enhancement in patients with abdominal aortic aneurysms.

Endovascular repair (EVAR) of abdominal aortic aneurysms (AAA) is an established alternative option to conventional surgery for AAA, provided optimal anatomical morphology of the aneurysm sac, neck and outflow exists. In most documented series of EVAR, type-II endoleak occurrence is a universal procedural drawback. This is referred to as the Achilles heel of EVAR. This morphological study, addressing predominantly non-aneurysmal aortic anatomy, reveals the dyssynchronous origins of the renal ostia, ectopia of the superior mesenteric artery and median sacral artery, variations in the length of the infrarenal abdominal aorta, multiple mainstem renal arteries, and the presence of accessory renal arteries (in 13% of cadavers). Such potential vascular anomalies need careful consideration pre-operatively prior to EVAR. In a prospective, clinical study of EVAR in 163 patients over 60 months, using four different aortic stent devices, we demonstrated an intraprocedural type-II endoleak rate, before exclusion, of 3% (5/163). Most were related to patent lumbar arteries. An active policy of intraprocedural aneurysm pressure sac measurement and angiography was used to demonstrate type-I and type-II endoleaks, focusing on the applied anatomy of aortic side branches and variations. Selective intraprocedural coil embolisation and thrombin injection into the sac was utilised to thrombose persisting and large lumbar arteries that predisposed to retroleaks. We recorded a low incidence of persisting type-II endoleaks using this proactive treatment strategy by addressing variant aortic morphology and patent lumbar arteries during EVAR. One aneurysm-related death (0.6%) was observed due to late rupture after EVAR, and a single intraprocedural death was related to unpredictable aneurysm rupture. In conclusion, comprehensive anatomical knowledge of the abdominal aorta and its main collateral side branches, including variations, is a fundamental prerequisite if satisfactory and predictable results are to be achieved after EVAR, especially regarding prevention, diagnosis and treatment of type-II endoleaks. Intraprocedural aneurysm sac pressure monitoring, coil embolisation and the use of injection of thrombin into the aneurysm sac of selected patients is useful in reducing the incidence of post-EVAR type-II persisting endoleaks.

Adult↗
PubMedDate not supplied

Carotid stenosis and carotid plaque analysis relevant to carotid endarterectomy and stent-assisted angioplasty.

The primary objective of this cadaveric study was to review the morphological variations of the anatomy of the human carotid artery bifurcation relevant to carotid endarterectomy (CEA) and carotid artery stent-supported angioplasty (CSSA). We quantify carotid bifurcation plaque morphology. Results showed that the angle of deviation at the origin of the internal carotid artery (ICA), in relation to the common carotid artery (CCA), measured a mean of 21.8 degrees with a range from seven to 45 degrees. This anatomical finding is important for the interventionalist concerned with insertion of a carotid stent. The angle of the ICA origin may be an independent risk factor for early atherosclerotic changes at the ICA bulb. Carotid bifurcation plaque was observed in a small, random cohort of seven out of 13 cadavers, and contributed to a mean stenosis of 15.2% (range 5.0-34.8%). Plaque morphology (n = 7) showed haemorrhage (29%), superficial thrombosis (57%), calcification (71%), areas of focal necrosis (71%), neovascularisation (14%) and infiltrates (29%). Ulcerations were not detected. Although four out of 13 patients (31%) died of a cerebrovascular accident, the cause of cerebral apoplexy was thought not to be associated with the carotid bifurcation pathology. 'Re-boring' of occluding plaque, as in CEA, offers potential volumetric anatomical advantage over CSSA within the carotid bifurcation and bulb. In conclusion, precise and applied knowledge of carotid bifurcation anatomy is critical to reduce technical complications during CEA or CSSA. This information may reduce potential dangers of iatrogenic thrombo-embolism and ensuing neurologic deficits. Patients with low-grade carotid stenosis, evidence of focal plaque necrosis, are at risk of spontaneous plaque cap rupture, distal thromboembolism and stroke.

Aged↗
PubMedDate not supplied

Endovascular aortic aneurysm repair by a multidisciplinary team: lessons learned and six-year clinical update.

BACKGROUND: Endovascular aneurysm repair (EVAR) (using an Federal Drug Association-approved AneuRx device) compared to conventional surgical repair of abdominal aortic aneurysm (AAA) previously rendered favourable outcomes regarding post-operative pain, avoidance of laparotomy, and rapid rehabilitation and hospital discharge in high-risk patients, including octagenarians. OBJECTIVES: To assess the safety, reduction in aneurysm-related deaths, and interim survival data up to 72 months after AAA exclusion by endoluminal endografts (EVAR). DESIGN: We carried out an open, controlled, prospective, multidisciplinary EVAR study for the period 1998 to 2003 (six years). In the earlier part of the study, EVAR was compared with previously published results of conventional open aneurysmectomy surgery. SETTING: Heart Unit, Panorama Medi-Clinic, Parow, South Africa. PARTICIPANTS: We recruited adult male and female patients presenting with AAA and fulfilling the inclusion criteria for endovascular repair, as recommended by the consensus 2003 meeting of the Vascular Association of South Africa (VASSA). All patients were offered open surgery as an alternative and were entered into the VASSA EVAR trial registry. Pre-operatively, AAA anatomy was assessed by spiral-computed tomography (CT), and selectively with conventional angiography and intravascular ultrasound (IVUS). Informed consent was obtained in accordance with the recommendations of the Senate of Surgery Paper 2, Ethical Guidelines, Great Britain and Ireland. Patients underwent EVAR by a multidisciplinary interventional team. INTERVENTIONS: Two hundred and seven adult patients with AAA were assessed. Forty-four of the 207 (21.2%) were excluded from EVAR because of irreversible comorbid factors and complex aneurysm morphology. One hundred and sixty-three patients (78%), with a mean age of 70.7 years (range 60-91 years), underwent EVAR (1998-2003). Five patients were lost to follow-up (3%). Median AAA diameter was 56.9 mm and ASA ratings were I, 1.2%; II, 15.9%; III, 57%; IV, 22.6%; and V, 2.4%. EVAR was performed in high- and low-risk categories of both sexes. Most patients were in ASA groups III and IV. DEVICES DEPLOYED: EVAR was performed using a selection of endografts over 72 months- AneuRx (Medtronic) 47; Talent (Medtronic) 49; Vanguard three; Zenith (Cook) one; Powerlink (Endologix) 62; and other, one. RESULTS: Thirty-day outcome: successful deployment 99%, primary stent patency 97%, surgical conversion 0.6%, procedural or intra-operative mortality 1.2%, 30-day mortality 4.3%, endoleaks 1.84%, and secondary intraprocedural endovascular interventions 24.5%. Perioperative mortality was 3.1% (one aneurysm related). One patient had suspected endograft infection. Late mortality was 21.4% (35 patients due to co-morbidities, and one was aneurysm related). Follow-up was a median of 28.3 months (range 1-69 months). In 163 patients, two persisting endoleaks (1.2%) were detected. Endotension was detected in 3/163 (1.8%) with average sac increase of 0.8 cm. Conversion to open surgery was needed in one patient (0.6%). Co-morbidities that contributed to late mortality included multi-organ failure, ischaemic heart disease (IHD), cardiomyopathy, renal failure, stroke and cancer. One procedural rupture was fatal (0.6%). Two late ruptures occurred; one was successfully endostented and the other patient died after a failed surgical intervention (0.6%). Endovascular repair of AAA is more expensive than conventional surgery. Introduction of the Endologix stent has reduced operative time from 120 to 60 minutes in un complicated patients. Newer-generation aortic stents allow better control of negative remodeling and stent migration. CONCLUSION: A multidisciplinary team can safely perform EVAR, with a low 30-day mortality rate in selected patients graded ASA II-IV and with favourable aortic aneurysm morphology. About 22% of patients with AAA are not suited for EVAR. Persisting late endoleaks occurred in 1.2% of the cohort study and were not device specific. Life-long follow-up post EVAR is a prerequisite to detect late device failure, endoleaks and aneurysm-sac enlargement, and to assure the durability of these midterm results. Short-term aneurysm rupture prevention is a predictable outcome in high-risk groups.

Aged↗