Acetylation phenotype is not associated with breast cancer.

In the present study, we have measured acetylation phenotype in 45 patients who had undergone surgical resection of a primary adenocarcinoma of the breast and in 48 patients or volunteer subjects with no breast disease. Phenotype was determined by measuring the ratio of N-acetylsulfamethazine to N-acetylsulfamethazine plus sulfamethazine in plasma 6 h after a p.o. dose of sulfamethazine. In the control group, there were 31 slow and 17 rapid acetylators, while in the breast patients, there were 25 slow and 20 rapid acetylators. The proportions of slow/rapid acetylators were not significantly different between the 2 groups (Pearson's chi 2 with Yates' correction = 0.45; P = 0.51). The data suggest that acetylation phenotype is not a useful risk prediction measurement in breast cancer.

Acetylation phenotype in colorectal carcinoma.

Sulfamethazine acetylation phenotype was determined in 49 patients with cancer of the colon or rectum, 41 old, and 45 young control subjects. Metabolic clearance of sulfamethazine, plasma ratio of N-acetylsulfamethazine:N-acetylsulfamethazine plus sulfamethazine and urinary ratio of N-acetylsulfamethazine:N-acetylsulfamethazine plus sulfamethazine were used to classify subjects into slow and fast acetylation phenotypes. All three measures gave similar results. The proportions of slow and fast acetylators were similar in both control groups and there were significantly more fast acetylators in the cancer group than in the control groups (chi 2 = 5.0-8.5; P less than 0.05). The data suggest that there may be an association between acetylation phenotype and colorectal carcinoma.

Acetylation phenotype and cytochrome P450IA2 phenotype are unlikely to be associated with peripheral arterial disease.

The hypothesis that cytochrome P450IA2 (CYPIA2) and/or N-acetyltransferase 2 (NAT2) may be involved in the pathogenesis of peripheral arterial disease was investigated in 90 Australian patients with significant disease and 81 matched control subjects. CYPIA2 and NAT2 phenotypes were determined from urinary metabolite patterns after an oral dose of caffeine. NAT2 phenotype was similar (chi 2 = 0.01; p = 0.98) in both atherosclerotic patients (43.3% rapid) and control subjects (42.0% rapid). CYPIA2 metabolism as measured by the median ratio of (1,7-dimethylxanthine + 1,7-dimethyluric acid)/caffeine was significantly induced by smoking in both patients with atherosclerosis (ratio of 6.5 in nonsmokers and 12.4 in smokers; p < 0.05) and control subjects (ratio of 8.2 in nonsmokers and 14.8 in smokers; p < 0.05), but values in atherosclerotic and control nonsmokers and smokers were similar. Probit transformation of the data revealed a trimodal distribution of ratios in control subjects who were nonsmokers, with 5% classified as poor metabolizers (homozygous rapid) and 95% as extensive metabolizers. The distribution of ratios in control subjects who were smokers was unimodal, whereas among the patients with arterial disease, both smokers and nonsmokers exhibited a bimodal pattern with 8.2% to 16% poor metabolizer and 84% to 91.8% extensive metabolizer phenotypes. When data from both nonsmokers and smokers were combined, the overall proportion of subjects who were poor metabolizers was not significantly different (chi 2 = 1.82; p = 0.18) between control subjects (3.8%) and patients with atherosclerosis (10.6%). Thus biotransformation of environmental or dietary aromatic or heterocyclic amines by NAT2 or CYPIA2 is unlikely to have a significant role in the cause or pathogenesis of peripheral arterial disease.

Haemoglobin, smoking and peripheral vascular disease.

One hundred and four patients with peripheral vascular disease requiring operation were reviewed retrospectively with respect to age, sex, preoperative haemoglobin, smoking habits and diabetic status. The preoperative haemoglobin levels and smoking status in 63 non-diabetic male patients with peripheral vascular disease were compared with a matched group of individuals treated for inguinal hernia. For all patients there was a significant correlation between smoking habits, preoperative haemoglobin level and the presence of peripheral vascular disease. The mechanisms by which smoking may damage the vascular tree are reviewed.

An audit of clinical teaching: an approach to one performance indicator of educational competence.

This paper describes a simple, self-administered audit of the year-by-year clinical examination results of 149 students taught by the writer (Dr X) over a 9-year tenure (1977-1985) as a Senior Lecturer in Surgery at the University of Western Australia. The clinical examination results of these 149 students are compared with the clinical examination results of a total peer group cohort of 1567 students taught by the writer's colleagues in the same academic department over the same years. The limitations and applicability of this method of audit are discussed, and it is argued that this type of self-assessment might be of use, in conjunction with other evidence, in the documentation of teaching expertise. Such documentation might be of use in applications for clinical teaching appointments or promotions.

Urinary Infection and Catheterization: A Case for a Catheter Team.

Forty-five out of 84 patients undergoing urethral catheterization developed significant bacteriuria. As might be expected, the infection rate grew with the increase in duration of catheterization, and it was higher in the elderly female patient. Some of the work on this problem is reviewed, and it is suggested that the formation of a catheter team might lead to improvements in catheter care.

Retained common bile duct calculi.

A method of elimination of gallstones remaining in the common bile duct after exploration of the duct is described. The retained stone is flushed through the common duct sphincter into the duodenum using rapid infusion of normal saline via a T tube. The method is quick and simple and is recommended as the first step to take in the management of this discomforting group of patients. The method is not without potential morbidity and should only be carried out under carefully controlled conditions.

Diet, liver function and dimethylhydrazine-induced gastrointestinal tumours in male Wistar rats.

Male Wistar rats fed a normal laboratory pelleted diet, when treated s.c. with 1,2-dimethylhydrazine (DMH) 10 mg/kg/wk survived the 24-week experiment, showed no signs of chemical toxicity or macroscopic liver damage, and developed mainly large-bowel tumours. Conversely, male Wistar rats treated with 20 mg/kg/wk DMH did not survive the full term of the experiment and developed ascites, pleural effusions and nodular livers. They also developed more small-bowel tumours than large-bowel tumours. The relationship between the predominant site of tumour development and dosage of DMH was highly significant.Male Wistar rats fed with an all-liquid diet (Vivonex) and treated with 20 mg/kg/wk DMH behaved quite differently both in terms of survival and site of tumour development. These rats survived the full term of the experiment, showed no signs of chemical toxicity, experienced minimal liver damage and developed predominantly large-bowel tumours. The protection afforded by the all-liquid diet against DMH toxicity and small-bowel tumour induction was statistically highly significant.A series of blood tests with special reference to liver function confirmed the highly significant degree of protection against liver damage afforded by the all-liquid diet.Sections of liver from treated rats were examined, and a simple pathological scoring system was devised which showed a highly significant difference in liver histology between standard diet and liquid-diet rats treated with 20 mg/kg/wk DMH.The results strongly suggest an association between severity of liver damage from DMH and the subsequent development of small-bowel tumours. The all-liquid diet protected rats from liver damage and these rats developed significantly fewer small-bowel tumours.

The effect of dietary lactulose on experimental large bowel cancer.

The hypothesis that feeding of lactulose might reduce large bowel tumour development was tested in an animal model. One hundred rats were divided into groups fed either a standard rat diet with water 'ad libitum', or the same diet but with 3.3% lactulose added to the drinking water. Large bowel tumours were induced by weekly injections of 1,2 dimethylhydrazine (DMH). There was no significant difference between the number of tumours found in the standard diet or the lactulose-treated groups. This result does not seem to support the colonic flora - bile salt theory of large bowel carcinogenesis.

Abdominal aortic aneurysms in Western Australia: descriptive epidemiology and patterns of rupture.

All abdominal aortic aneurysms presenting to hospitals and coroners in Western Australia over an 11-year period (January 1971 to December 1981) have been reviewed. A total of 1237 abdominal aortic aneurysms were found. After age and sex standardization it was apparent that the prevalence of diagnosis of abdominal aortic aneurysms had increased from 74.8 per 100 000 to 117.2 per 100 000 for men over 55 years of age (increase of 56.7 per cent) and from 17.5 per 100 000 to 33.9 per 100 000 for women over 55 years of age (increase of 93.7 per cent) during this period. One hundred and twenty-three patients were identified by coroner's autopsy after sudden death from ruptured abdominal aortic aneurysms in whom there had been no previous diagnosis of abdominal aortic aneurysm. Between 1971 to 1981, 478 patients underwent surgery; 225 had elective resection of their aneurysm with a 4.0 per cent fatality rate, and 253 had emergency operations with a 31.2 per cent fatality rate. Seasonal variations contributing to the date of emergency presentation or death from rupture of abdominal aortic aneurysms indicated a possible influence of colder weather upon rupture. It is hoped that the information provided in this paper will be of use to surgeons and physicians involved in health care planning for similar populations.

Prevalence of abdominal aortic aneurysm in Western Australia.

The prevalence of abdominal aortic aneurysm (AAA) in Western Australia was studied using health department mortality data. Age-standardized and age-specific mortality rates related to the disease were calculated for the period 1980-88. The mortality rate has risen by 36 per cent for men and 24 per cent for women. Most of this rise was due to an increase in non-hospital and emergency admission hospital deaths. The number of elective and emergency operations has also risen. Despite two decades of elective surgery, the mortality rate for AAA continues to rise. This rise is highly suggestive of an increasing prevalence. This contrasts with the decline in deaths from other manifestations of arteriosclerosis and provides support for a policy of screening for aneurysm.

Detection of reversible platelet aggregates in the blood of smokers and ex-smokers with peripheral vascular disease.

OBJECTIVE: To demonstrate that smoking increases platelet aggregation in vivo, that smoking cessation reverses platelet aggregation and that this explains, in part, why smoking perpetuates the development of peripheral vascular disease. DESIGN: Prospective case-control study involving three groups of patients: smokers with peripheral vascular disease, ex-smokers with peripheral vascular disease and smokers with peripheral vascular disease who quit smoking during the study. SETTING/PARTICIPANTS: Fourteen smokers and seven ex-smokers, new patients with confirmed peripheral vascular disease, attending the vascular clinic at Fremantle Hospital between February and November, 1988. INTERVENTIONS: Blood samples taken weekly from all subjects for five weeks. Week 1 was taken as the baseline before smoking cessation in the six smokers who were assigned to stop smoking during the study. MAIN OUTCOME CRITERIA: Platelet aggregate ratio, an indicator of in-vivo platelet aggregability where an increase in platelet aggregate ratio suggests a decrease in platelet function. RESULTS: Only three of six smokers stopped smoking for the duration of the study. Median platelet aggregate ratios were: smokers = 0.85 (range, 0.79-0.92) v. non-smokers = 0.93 (range, 0.91-1.00). The difference was statistically significant P less than 0.0002. The difference in platelet aggregate ratios between smokers and quitters was not statistically significant. CONCLUSIONS: This study demonstrated an increase in platelet aggregability in smokers compared to ex-smokers but there was no clear evidence that platelet function was fully reversed after only four weeks cessation of smoking. The data suggested that platelet function of the ex-smokers had fully reversed to normal over a longer period. This could explain the decreased incidence of complications of peripheral vascular disease in ex-smokers. The small number of patients able to quit smoking impeded this study.

The effect of cessation of smoking on the accumulative survival rates of patients with symptomatic peripheral vascular disease.

A study of the accumulative survival rates of 133 patients with symptomatic peripheral vascular disease was carried out comparing the survival rates of tobacco smokers and non-smokers. Within the smoking group, those who continued to smoke after the surgery were compared to those who ceased smoking. Of these patients with peripheral vascular disease, 86% were, or had been, smokers. Their survival rates were less than for those who had never been smokers. Of the smoking group, those who claimed to have ceased smoking had almost twice the chance of surviving five years than those who continued to smoke. From these data, we conclude that it is never too late to stop the smoking habit.

Final examinations in surgery: support for the retention of the clinical examination.

Students' results in the final M.B., B.S. (W.A.) examination in surgery between 1976 and 1979 inclusive (375 students) were analysed. Marks in all parts of the examination, namely clinical, multiple choice, essays, pathology, and fifth year multiple choice, were correlated with each other and the total mark in surgery. Multivariate analysis showed that the marks in the clinical examination accounted for most of the variation in a student's total mark, and this was only in part due to its heavy weighting in Western Australia. The authors of this paper strongly support the retention of the clinical examination in surgery and consider that the loading placed on this part of the final examination in Western Australia is justified.

Biliary bile acids in cholelithiasis and colon cancer.

The role of biliary deoxycholate as an endogenous colon carcinogen and the possible association between cholelithiasis and/or cholecystectomy and the subsequent development of large bowel cancer is unclear. This paper describes biliary bile acids analysis performed on 13 patients undergoing cholecystectomy for gall stones, 10 patients undergoing colonic resection for colon cancer, and eight control patients. For all 31 patients the total bile acids concentration was highly variable (8.3 mg/ml-106.5 mg/ml). The median ratio of primary to secondary bile acids was 2.7:1. The biliary bile acid ratios were similar in both control patients (3.7:1) and those with colon cancer (3.1:1), whereas patients with gall stones had significantly higher secondary bile acid levels in their biliary bile (ratio 1.9:1, p = less than 0.05). This result indicates that raised biliary deoxycholate concentrations are not present in patients with colon cancer and are therefore unlikely to be a major predisposing factor in the aetiology of this disease. It is unlikely that cholelithiasis and/or cholecystectomy predispose to the subsequent development of colon tumours.

Changes in tobacco advertising in Western Australian newspapers in response to proposed government legislation.

The number of cigarette and tobacco advertisements in the major Western Australian newspapers was counted for the six-month period June to November in the years 1981 and 1983. The latter period covered the introduction of the Western Australian Government's Tobacco (Promotion and Sales) Bill 1983 and the debate surrounding it. The change in the volume of cigarette advertising in Western Australia in those two years was compared with that which occurred in comparable Queensland papers in the same period. Three major factors emerged: (i) the volume of cigarette advertising was much higher in Western Australia in 1983 compared with 1981; (ii) the volume of advertising increased markedly in Western Australia when legislative action was threatened, and remained at very high levels until the Bill failed; and (iii) the number of cigarette advertisements placed in the Queensland papers surveyed fell between 1981 and 1983. The findings are presented in support of the view that the tobacco industry made a powerful and organized attack to defeat the proposed legislation; the means it adopted to do this are discussed.

Incisional hernias are more common in aneurysmal arterial disease.

OBJECTIVE: To test the hypothesis that incisional hernia was a more frequent complication following aortic reconstructive surgery in patients with aneurysmal as opposed to occlusive aortic disease. DESIGN: A retrospective review. MATERIALS AND METHODS: All patients having aortic reconstructive surgery at a teaching hospital between 1988 and 1992 were identified and recalled to be examined for evidence of an incisional hernia. RESULTS: Of the 134 patients having aortic reconstructive surgery, 87 were available to be examined by an independent clinician. The overall incisional hernia rate was 28%. Patients with aneurysmal disease were significantly more likely to develop an incisional hernia after elective surgery than patients with occlusive disease (p = 0.04). None of the other variables investigated, including age, chronic obstructive airways disease, diabetes, smoking, wound infection, obesity, length of intensive care unit stay and number of units of blood transfused, were significantly related to the complication of incisional hernia. CONCLUSION: Incisional hernia is a common complication of aortic reconstructive surgery, especially in patients with aneurysmal disease.

Diverticular disease of the colon and gallstones in New Zealand and England.

The clinical presentation and subsequent treatment of 160 consecutive patients with proven diverticular disease of the colon from the Auckland Hospital, New Zealand were compared with 182 consecutive patients admitted to St. Bartholomew's Hospital, London. There were significant differences in sex incidence, in the ages of the male patients at presentation, patient symptoms, extent of disease and methods of surgical treatment. These probably reflect differences in the types of National Health Services of the two countries, rather than differences in the natural history of diverticular disease of the colon. Overall, the 342 patients studied show a very good correlation with other large series published over the last 10 years. This study confirms the previously reported association between diverticular disease of the colon and gallstones. It confirms that gallstones are more common in female patients with or without diverticular disease. It suggests that Auckland patients with gallstones are more likely to have had a cholecystectomy than London patients. The possible role of dietary fiber in the aetiology of both gallstones and diverticular disease of the colon is discussed.