Diet affects reflux in a rural African community.

Reflux in this region of South Africa is known to be more frequent and less acidic than in other countries. We investigated the relationship between reflux and diet. We recruited 57 healthy participants. We carried out ambulant oesophageal pH-impedance monitoring for 24 hours. We used software and visual review to analyse data and to identify episodes of reflux and rapid alkaline rises in the stomach. A usual pattern diet questionnaire provided data on frequency of consumption of common foods. Associations between reflux, gastric pH and dietary components were sought using analysis of variance, and regression analyses. Diet was strongly based on maize. Protein was principally from milk, eggs, chicken and beans. Fat was principally from cooking oil. Fruit and vegetables were consumed moderately frequently. Milk consumption was associated with an increase in total reflux (P = .022), weakly acid reflux (P = 0.015) and supine reflux (P = 0.001), and a decrease in the time that gastric pH was higher than 4 (P = 0.030). Fat was associated with an increase in acid reflux (P = 0.046) and a decrease in time that gastric pH was higher than 4 (P = 0.005). Fruit consumption was associated with increases in liquid-only refluxes(P = 0.007), and upright refluxes (P = 0.048). Maize meal was associated with a reduction in rapid alkaline rises in the gastric lumen (P = 0.015). Diet significantly affects reflux in this community. What is normal in apparently healthy people in various parts of the world differs significantly.

Normal values of 24-hour ambulatory esophageal impedance-pH monitoring in a rural South African cohort of healthy participants.

There are no data on 24-hour multichannel intraluminal impedance and pH monitoring in African populations. The purpose of this study was to provide the normal values of esophageal impedance and pH monitoring in a rural African populations. South African healthy rural participants were recruited and underwent 24 hours of esophageal impedance and pH monitoring. The median and the 95th percentiles of the total reflux episodes were 49 and 97, respectively, of which the corresponding number of acidic, weakly acidic, and weakly alkaline reflux were 15 and 55, 17 and 51, and 8 and 36, respectively. The compositions of the total reflux were 5 and 21 for liquid, 27 and 72 for mixed, and 10 and 39 for gas reflux, respectively. The median bolus clearance was 18 seconds and the median bolus exposure was 14 minutes/24 hours. The proximal extent was 6%. The 95th percent time of esophageal exposure to acid was 8.6 in 24 hours. Female and overweight participants were associated with an increased number of reflux events. There were more reflux episodes, and of which, more were weakly alkaline compared with previous similar studies. The findings provide reference values of gastroesophageal reflux for a South African rural population.

Essential professional duties for the sub-Saharan medical/dental graduate: An Association of Medical Schools of Africa initiative.

BACKGROUND - Globally, human resources for health are being optimized to address the increasing health burden and concomitant increased demands on health professionals. These demands are even more exacting in Sub-SaharanAfrica considering the shortage of health care workers, especially physicians. The noteworthy efforts at deploying task-shifting to address this situation not-withstanding, the situation also signals the need to re-define the objectives of medical instruction to ensure effective and contemporary medical practice in a mostly physician-led health workforce across the sub-continent. In this regard, medical and dental graduates must be educated to perform certain minimum essential professional duties competently. Essential Professional Duties are locally relevant professional activities of international standard that represent identifiable outcomes against which the effectiveness of physicians in a specific community can be measured to ensure social accountability. PROCEDURE AND PRODUCT - The Association of Medical Schools of Africa has developed the 'Essential Professional Duties for sub-Saharan medical and dental graduates' to ensure these physicians provide safe and effective contemporary medical/dental practice on the sub-continent. The duties have been grouped into those required for basic patient care, basic administrative skills, basic emergency care, communication, inter-professional relationships, self-directed learning and social responsibilities. Their relevance and suitability have been evaluated prior to their adoption by the Association. CONCLUSION; These Essential Physician Duties have been developed to serve as targets for health professionals training instruments and thus give direction to health system strategies. It is hoped that they will be adopted by medical and dental schools across sub-,. Saharan Africa.

South African medical schools: Current state of selection criteria and medical students' demographic profile.

BACKGROUND: Selection of medical students at South African (SA) medical schools must promote equitable and fair access to students from all population groups, while ensuring optimal student throughput and success, and training future healthcare practitioners who will fulfil the needs of the local society. In keeping with international practices, a variety of academic and non-academic measures are used to select applicants for medical training programmes in SA medical schools. OBJECTIVES: To provide an overview of the selection procedures used by all eight medical schools in SA, and the student demographics (race and gender) at these medical schools, and to determine to what extent collective practices are achieving the goals of student diversity and inclusivity. METHODS: A retrospective, quantitative, descriptive study design was used. All eight medical schools in SA provided information regarding selection criteria, selection procedures, and student demographics (race and gender). Descriptive analysis of data was done by calculating frequencies and percentages of the variables measured. RESULTS: Medical schools in SA make use of academic and non-academic criteria in their selection processes. The latter include indices of socioeconomic disadvantage. Most undergraduate medical students in SA are black (38.7%), followed by white (33.0%), coloured (13.4%) and Indian/Asian (13.6%). The majority of students are female (62.2%). The number of black students is still proportionately lower than in the general population, while other groups are overrepresented. CONCLUSION: Selection policies for undergraduate medical programmes aimed at redress should be continued and further refined, along with the provision of support to ensure student success.

Maize meal predisposes to endemic squamous cancer of the oesophagus in Africa: breakdown of esterified linoleic acid to the free form in stored meal leads to increased intragastric PGE2 production and a low-acid reflux.

Endemic cancer of the oesophagus in Africa is associated with the use of maize as the staple. In one African community endemic cancer of the oesophagus has been shown to have a strong statistical association with the consumption of foods based on maize in the meal form. A strong association with consumption of maize meal has also been shown in a region of Italy. It has been argued in the past that the association with maize consumption is due to a fortuitous association; or due to the nutritional deficiencies of maize meal; or due to fungal contamination. We argue that maize meal is a distinctly different food from whole maize, and that nutritional content as much as deficiency is responsible for predisposition of the oesophagus to carcinogenesis. An important factor is the breakdown of esterified linoleic acid to the free form in stored maize meal. This leads to excess production of prostaglandin E2 in the stomach. The excess Prostaglandin E2 causes a low-acid duodenogastro-oesophageal reflux, which predisposes to carcinogenesis. Supporting evidence is available that the steps of this mechanism occur in endemic areas, and that they are associated with the carcinogenic process. Health measures including poverty alleviation, health education, and monitoring and control of maize meal storage and content may be required to reduce the incidence of this disease in Africa.

Glucose tolerance in rural women with pre-eclampsia.

OBJECTIVE: To determine the relationship between pre-eclampsia and glucose intolerance among rural women from the Transkei region of South Africa. METHODS: Women with confirmed pre-eclampsia underwent a 75 g, 3-hour oral glucose tolerance test. A control group of normotensive pregnant women were subjected to a similar glucose tolerance test. Pre-eclampsia was defined as blood pressure (BP) of at least 140/90 mmHg occurring for the first time after mid-pregnancy, in association with proteinuria. The control group comprised women with singleton pregnancy and normal BP, with age, parity and gestational age comparable to those of the pre-eclampsia group. RESULTS: There were 117 subjects in the pre-eclampsia group and 94 in the normotensive pregnancy group. Mean fasting plasma glucose levels in the pre-eclampsia group (3.88 +/- 0.05 mmol/l) were similar to levels in the normotensive group (3.97 +/- 0.05 mmol/l, p = 0.214). Peak post-load plasma glucose levels in the pre-eclampsia group (5.96 +/- 0.12 mmol/l) were similar to levels in the normotensive group (5.71 +/- 0.13 mmol/l, p = 0.180), and post-load incremental glucose area under the curve in the preeclampsia group (4.16 +/- 0.21) was similar to that in the normotensive group (3.95 +/- .21, p = 0.495). CONCLUSION: Rural women with pre-eclampsia from the Transkei region of South Africa have normal glucose tolerance.

Gastric luminal epidermal growth factor is affected by diet.

OBJECTIVE: Diet is an area of major interest to those investigating the causes of cancer of the oesophagus in the Transkei. This study looked at the associations between intragastric epidermal growth factor level, diet and intragastric pH. SETTING AND SUBJECTS: A dietary survey was co-ordinated with studies of gastric luminal epidermal growth factor and gastric fluid pH in 120 rural Transkeians. RESULTS: Gastric fluid epidermal growth factor was associated with low dietary intake of animal products (p = 0.002) and vegetables (p = 0.026). There was no association with pH. CONCLUSION: A dietary subgroup has been identified in the Transkei population with high levels of epidermal growth factor in the upper gastrointestinal lumen. This adds to previously demonstrated diet-related changes in the upper gastrointestinal tract in Transkei. These changes may affect the disease pattern of the population.

Bimodal distribution of fasting gastric acidity in a rural African population.

SETTING: The people of Transkei eat a diet high in linoleic acid, the principal fatty acid in maize. The theory has been put forward that a diet high in linoleic acid and low in fat and riboflavin, such as the traditional diet in Transkei, results in overproduction of prostaglandin E2 in the gastric mucosa, and that this overproduction in turn causes a suppression of gastric acid production. OBJECTIVE: To investigate the effect of diet on fasting gastric pH in a rural black African population. DESIGN: Fasting gastric acid samples were obtained by fine nasogastric tube aspiration from 150 volunteers at a rural health clinic. The pH of these samples was measured and a full dietary questionnaire was used. Helicobacter pylori serology was done on a subgroup of 30 volunteers. RESULTS AND CONCLUSIONS: A bimodal pH distribution was found. Approximately half the population had a gastric pH within the range 1-4. Half had a pH of over 4. A high pH was significantly associated with consumption of maize (p = 0.006), and with consumption of both pumpkin and beans (p = 0.006). A high proportion of this rural African population has a diet-associated abnormally high gastric pH. The pattern of upper gastrointestinal disease may be significantly affected by diet in this community and in others with a similar diet.

Prostaglandin E2 is raised in kwashiorkor.

OBJECTIVE: Infection is a common occurrence in children with kwashiorkor. It has been suggested that infection in kwashiorkor results from immune depression, and that the immune depression of kwashiorkor is caused by a diet-associated elevation of prostaglandin E2 (PGE2). The purpose of this study was to determine whether levels of PGE2 are abnormal in children with kwashiorkor. SETTING AND SUBJECTS: Plasma PGE2 and plasma proteins were measured in children admitted with oedematous kwashiorkor, and compared with PGE2 in children with cerebral palsy. RESULTS: Plasma PGE2 was higher in children with kwashiorkor than in control children (7.25 +/- 3.5 v. 3.51 +/- 1.59, P < 0.01). Within the kwashiorkor study group there was a significant negative correlation between log-transformed serum PGE2 and total plasma protein (r = -0.59, P < 0.001), plasma albumin (r = -0.63, P < 0.001), weight-for-age (r = -0.37, P < 0.05), and height-for-age (r = -0.37, P < 0.05). The difference in mean values of PGE2 in children with kwashiorkor who recovered from the illness and those who died was not significant (7.1 +/- 2.6 v. 9.1 +/- 4.8, P = 0.36). CONCLUSION: Significantly higher PGE2 levels in children with kwashiorkor provide adequate reason for the depression of immune function known to occur in these children. Elevated PGE2 levels may also be implicated in other components of the illness.

Serum leptin concentration in a rural African population.

OBJECTIVE: To determine the serum leptin concentration in a cohort of healthy rural Africans, it's relation to the commonly used anthropometric measures of obesity and its relation to the patterns of distribution of fat in the body. DESIGN: A cross-sectional population survey. SETTING: Baziya area, Transkei region, South Africa. SUBJECTS: One hundred and thirty five (79 females and 56 males) healthy adults from the Baziya location, Transkei aged 17-70 years were selected by stratified random sampling. MEASUREMENTS: Anthropometric measurements of height, weight, and skinfold thickness at the biceps, triceps, subscapular and suprailiac sites and derived total body fat and ratios of fat distribution. Fasting serum leptin using the sandwich ELISA method. RESULTS: Skinfold measurement was significantly higher in the females than the males throughout the age range. Centralization of body fat to the trunk was significantly greater in the males than in the females. Serum leptin concentration was higher in the females (mean = 13.5 ng/ml; 95% confidence interval = 10.0-16.8) than in the males (mean = 5.2 ng/ml; 95% confidence interval = 2.8-7.6) (p < 0.001). The gender difference in leptin concentration persists when expressed as serum leptin per kilogram of fat mass (serum leptin (ng/ml)/FM). The mean value for the males was 5.1 ng/ml/kg (95% confidence interval = 2.9-7.3) compared to the mean value for females of 6.9 ng/ml/kg (95% confidence interval = 5.4-8.3) (p < 0.05). In the females BMI and body fat were significant contributors to the variance in serum leptin. In the males the upper-to-lower trunk skinfold thickness ratio and BMI were the significant contributors to the variance in serum leptin concentration. Deposition of fat in the abdomen did not have a significant contribution to the variance in circulating leptin in both sexes. CONCLUSION: Serum leptin concentration in rural Africans is similar to that observed in other communities with the exception that regional fat distribution has a significant influence on the leptin levels in the males.

Impact of the problem-based learning curriculum on the learning styles and strategies of medical students at the University of Transkei.

OBJECTIVES: This is a longitudinal cohort study of the learning styles and strategies of medical students in a problem-based, community-based curriculum as they progressed through the medical course. The purpose was to monitor and evaluate whether the programme was fulfilling the objective of producing self-directed and lifelong learners. METHODS: The short version of the Lancaster Inventory of Learning Styles was administered to the students on admission and thereafter on a yearly basis through the first 4 years of the medical course. Data were fed onto a database and subsequently analysed using a commercially available statistical package. RESULTS: 140 students (falling to 106 by year 4) were interviewed and followed up through the study period. Of the students 75% were black and 25% were of Asian descent. On admission the students had high scores for individual achievement motivation, and for meaningful learning. They had moderate scores for reproducing learning, comprehension learning, operation learning and versatile learning. They had low scores for learning pathologies, especially globetrotting and improvidence. There was no sexual difference in learning styles. Asian students had significantly higher scores for meaningful learning and for versatile learning. The effect of the problem-based curriculum was to reduce the score for individual achievement, decrease the score for fear of examinations, increase the score for operation learning, increase the score for versatile learning, increase the score for syllabus boundness, and decrease the scores for learning pathologies, especially for improvidence and globetrotting. By year 4, there was similarity in the learning styles of black and Asian students. CONCLUSION: The problem-based curriculum had a positive effect on the learning styles of the students, especially the black students.

Serum free carnitine levels in children with kwashiorkor.

OBJECTIVE: To determine the serum free carnitine concentration in normally nourished children and in children with kwashiorkor and to relate the carnitine concentration to the ability to oxidise exogenous long chain fatty acids in the body. STUDY DESIGN: A cross-sectional comparative study of two age-matched groups. SUBJECTS: Forty seven children with kwashiorkor and 47 age-matched normally nourished children. MAIN OUTCOME MEASURES: Fasting blood samples were enzymatically analysed for free carnitine levels. 13C labelled hiolein was administered orally and the recovery of 13C from the breath air was monitored after administration of the feed. The cumulative per cent dose (CUMPD) recovery of 13C 16 hours after the ingestion of labelled hiolein was determined. RESULTS: Normal children had significantly higher free carnitine concentrations (mean = 60.7 mumol/l; 95% confidence interval of the mean = 42.7-77.8) than the kwashiorkor children (mean = 16.5 mumol/l; 95% confidence interval of the mean = 11.3-19.8)(p < 0.001). There was no correlation between serum free carnitine concentration and serum albumin in kwashiorkor subjects, but there was a significant correlation between serum free carnitine concentration and the degree of weight loss as indicated by the weight: weight for age and sex ratio. The greater the weight loss, the lower the serum carnitine concentration amongst the kwashiorkor children (r = 0.46; p < 0.01). There was a linear relationship between serum free carnitine and hiolein oxidation (r = 0.89; p < 0.001). CONCLUSION: There is carnitine deficiency in kwashiorkor, and that the impaired lipid oxidation in kwashiorkor is related to this deficiency.

Protein-losing enteropathy in Transkeian children with morbid protein-energy malnutrition.

A commercially available radial immunodiffusion assay was used to measure serum and faecal alpha 1-antitrypsin concentrations as well as alpha 1-antitrypsin clearance in 17 children with kwashiorkor, 11 children with marasmic kwashiorkor, 10 children with marasmus, and 16 normal children. Serum alpha 1-antitrypsin concentrations were significantly higher than normal in the marasmus and marasmic kwashiorkor groups, and significantly lower than normal in the kwashiorkor group. The intestinal clearance of alpha 1-antitrypsin was significantly higher than normal in the marasmus and marasmic kwashiorkor groups, and significantly lower than normal in the kwashiorkor group. There was a significant inverse correlation between the alpha 1-antitrypsin clearance and serum albumin concentration in the marasmus and marasmic kwashiorkor groups. No such correlation was evident in the kwashiorkor group. It is concluded that protein-losing enteropathy is likely to play a significant role in the development and perpetuation of hypo-albuminaemia in children with marasmus and marasmic kwashiorkor but not in those with kwashiorkor.