Search PubMed⌕ Search

Biomedical subjects

M Gracey

Publications and source records attributed to M Gracey.

At least 109 records · Page 6Linked to original sources
PubMed1984

Evolution of obesity in young people in Busselton, Western Australia.

The height and weight measurement of 928 young people of Busselton were collected over a period of up to 11 years. The prevalence of obesity was low in early childhood and increased progressively through adolescence and adulthood, so that 9% of male subjects and 16% of female subjects aged 21 years or over, were obese. The prevalence and degree of obesity were both greater in female subjects than in male subjects. Although most obese young adults were not obese in childhood, 50% of those who were obese between the ages of 9 and 14 years were still obese when examined in young adult life, and were at greater risk of becoming obese adults than were their non-obese peers. Most subjects who subsequently became obese young adults were significantly heavier than their non-obese peers at all ages from the age of 6 years.

Adolescent↗
PubMed1984

Mechanisms of malabsorption in the "Contaminated Small-Bowel syndrome".

The mucosa of the upper small intestine in humans is repeatedly exposed to potentially harmful environmental influences: infective, toxic and antigenic. One of the most significant manifestations of the control over environmental risks is how the upper intestinal milieu is kept relatively sterile and pathogen-free despite constant exposure to a potentially hostile and pathogen-ridden environment. This control is lost in the so-called "Contaminated Small-Bowel Syndrome" when profuse numbers of bacteria contaminate the contents of the upper bowel. This can occur in a vast array of clinical situations ranging from infancy to old age. The consequences of upper intestinal bacterial overgrowth are very diverse. The mechanisms causing diarrhoea and malabsorption in this syndrome illustrate facets of pathophysiology of many inter-relating processes of intestinal digestion and absorption.

Carbohydrate Metabolism↗
PubMed1984

Aspirin in acute gastroenteritis: a clinical and microbiological study.

Soluble aspirin given by mouth in divided dosage decreased intestinal fluid loss in infants and young children with acute gastroenteritis. The treated group had significantly less diarrhea, which ceased earlier and needed less intravenous therapy, than a randomly selected control group given an indistinguishable placebo. This effect of aspirin occurred with diarrhea caused by Salmonella, Aeromonas, Escherichia coli producing heat-labile toxin, and rotavirus, but not with diarrhea associated with strains of E. coli producing heat-stable toxin.

Acute Disease↗
PubMed1984

Australian longitudinal study of time and order of eruption of primary teeth.

Timing and sequence of eruption of primary teeth were studied longitudinally in 164 healthy Australian children. Eruption of primary teeth typically began between 7 and 8 months and was completed by 28 months. Tooth eruption was not significantly related to growth rate or to psychomotor maturity. Comparison of the eruption ages in this study with those from longitudinal studies in other countries suggests that no real changes in these have occurred over 40 yr despite increased affluence in industrialised countries over that period.

Age Factors↗
PubMed1984

Biotyping and virulence factors in clinical and environmental isolates of Aeromonas species.

Biochemical characteristics and virulence factors were compared in 147 Aeromonas spp. isolated from patients with diarrhea and in 94 strains isolated from metropolitan water supplies in the same area during the same period. Fermentation of arabinose occurred with 58.5% of the environmental strains and 15% of the clinical isolates; 39.4% of the strains from water and 6.8% of the fecal isolates fermented salicin. The frequency of esculin hydrolysis was the same in both groups. Ninety-one percent of clinical isolates and 70.2% of environmental strains were enterotoxigenic and, except for four clinical isolates, all of these strains also produced hemolysins. Hemagglutination that was inhibited by fucose and mannose but not by galactose was found in 67% of the water isolates and 10.2% of the clinical strains. Although the distribution of several characteristics differs in clinical and environmental strains, many of the strains found in water have properties identical with those of the clinical isolates. We suggest that such strains may be potential enteric pathogens.

Aeromonas↗
PubMed1984

Isolation of Aeromonas hydrophila from a metropolitan water supply: seasonal correlation with clinical isolates.

The occurrence of Aeromonas spp. in the metropolitan water supply of Perth, Western Australia, Australia, was monitored at several sampling points during a period of 1 year. Water within the distribution system conformed to international standards for drinking water but contained Aeromonas spp. in numbers comparable to those in raw surface water, although this water was free of Escherichia coli. Coliforms and E. coli were found in raw surface waters, and Aeromonas spp. were found in raw water from surface and underground sources. Chemical treatment, followed by chlorination at service reservoirs, resulted in water free of E. coli and a decrease in the number of Aeromonas spp. Aeromonas spp. were found in the greatest numbers in summer. Multiple regression analysis showed that growth of Aeromonas spp. in chlorinated water was related to water temperature, residual chlorine, and interaction between these variables. The incidence of Aeromonas-associated gastroenteritis, determined from isolates referred to us for enterotoxin testing, paralleled the pattern of isolation of Aeromonas spp. in water within the distribution systems. We suggest that the presence of Aeromonas spp. in drinking water needs public health appraisal and that further work should be undertaken to permit reevaluation of standards for the quality of drinking water.

Aeromonas↗
PubMed1984

Isolation of Aeromonas spp. from an unchlorinated domestic water supply.

The recovery of Aeromonas spp. from the unchlorinated water supply for a Western Australian city of 21,000 people was monitored at several sampling points during a period of 1 year. Membrane filtration techniques were used to count colonies of Aeromonas spp., coliforms, and Escherichia coli in water sampled before entry to service reservoirs, during storage in service reservoirs, and in distribution systems. Aeromonas spp. were identified by subculture on blood agar with ampicillin, oxidase tests, and the use of Kaper medium and then were tested for production of enterotoxins and hemolysins. During the same period, two-thirds of all fecal specimens sent for microbiological examination were cultured on ampicillin-blood agar for Aeromonas spp. Recovery of Aeromonas spp. from water supplies at distribution points correlated with fecal isolations and continued during autumn and winter. Coliforms and E. coli were found most commonly in late summer to autumn. This pattern differs from the summer peak of Aeromonas isolations both from water and from patients with Aeromonas spp.-associated gastroenteritis in Perth, Western Australia, a city with a chlorinated domestic water supply. Of the Aeromonas strains from water, 61% were enterotoxigenic, and 64% produced hemolysins.

Aeromonas↗
PubMed1984

Hemagglutination patterns of Aeromonas spp. in relation to biotype and source.

Aeromonas spp. show patterns of hemagglutination with human group O cells in the presence of fucose, galactose, and mannose. These patterns are related to biotype as well as to the source of isolates. There was good correlation between hemagglutination pattern and the presence of diarrhea among strains isolated in Western Australia, which was the only source with adequate data for classification of children with an without diarrhea. Most of the environmental and other nonfecal isolates produced patterns different from those in strains associated with diarrhea. These results suggest that hemagglutinins should be considered with enterotoxins as virulence factors in Aeromonas spp.

Aeromonas↗
PubMed1984

Studies with enterotoxigenic microorganisms: effects of candidate antidiarrhoeals in experimental animals in vivo.

Chlorpromazine or aspirin alone, when given to rats parenterally, reduced intestinal fluid secretion induced by cell-free preparations of enterotoxigenic organisms including Escherichia coli, Aeromonas hydrophila, Staphylococcus pyogenes, and Salmonella typhimurium. A combination of chlorpromazine-aspirin given parenterally caused much more marked reduction of fluid secretion. Indomethacin also had significant antisecretory effects against a range of bacterial enterotoxins, while loperamide was effective against heat-labile toxin (LT)-positive E. coli and A. hydrophila. Nicotinamide increased net fluid absorption in the presence of E. coli LT, A. hydrophila, and S. typhimurium. Of the adsorbents tested, aluminum hydroxide showed a positive effect only with E. coli LT and A. hydrophila, while cholestyramine affected net fluid flux only with E. coli ST (heat-stable toxin). Charcoal was effective against all microorganisms tested but only when premixed with the perfusate before the experiments. Aspirin and chlorpromazine probably act at multiple sites to decrease intestinal secretion, and the combination of low doses of these drugs with possibly different sites of action may have advantages over a single agent used in high dosage.

Aluminum Hydroxide↗
PubMed1983

Infectious disease in Aboriginal infants and children in Western Australia.

Over the decade from 1971 to 1980, there was a decline in Western Australia in the number of Aboriginal infants and children admitted to hospital with infections. The most marked change occurred in admissions for gastroenteritis and other infections in the Kimberley region in the far north of the State. Despite this decline, there is still a very wide gap between the rate of admission to hospital for infectious diseases of Aboriginal and that of non-Aboriginal infants and children. The decline reported here is considered to reflect improvements in health status caused by several interrelating factors, including improvement in the general standard of living, housing and hygiene, and the provision of comprehensive, community-based health programmes. Environmental contamination is still a major factor causing ill health in Australian Aboriginal communities.

Adolescent↗
PubMed1983

Enterotoxigenic Aeromonas hydrophila and diarrhoea in adults.

Aeromonas hydrophila was isolated from the faeces of 32 patients during a nine month period in three hospitals in Western Australia. All 32 isolates produced enterotoxin which was detected by the suckling-mouse test, and all patients except one had diarrhoea. Treatment should be considered in patients with chronic diarrhoea and in those with malignant disease or with hepatobiliary disease who are at risk of developing aeromonas septicaemia.

Adult↗
PubMed1983

A modified infant mouse assay for bacterial enterotoxins.

The reproducibility of the infant mouse assay for Escherichia coli ST and heat-labile enterotoxins of Aeromonas spp. is improved if both intestinal weight to remaining body weight ratio (IW/RBW) and the amount of diarrhoea produced are considered as criteria for classifying enterotoxigenic strains. Animals with profuse diarrhoea may have IW/RBW ratios below the widely accepted critical value for a positive test. Using pools of supernatants from broth cultures of three different strains of E. coli, 15% of ST producers would have been regarded as negative using IW/RBW ratio as the only criterion of a positive test. In testing single supernatants, 25% of ST producing E. coli would not have been correctly classified using IW/RBW alone. A scoring system which incorporates IW/RBW ratios and the amount of diarrhoea produced improves the usefulness of the test by allowing clear separation of positive and negative strains. The scoring system is also applicable to older mice for assay of E. coli ST so that a wider age range of mice can be used allowing increased use of animal facilities.

Aeromonas↗
PubMed1983

Studies on enterotoxigenic Escherichia coli isolated from persons without diarrhoea in Western Australia.

The epidemiology of enterotoxigenic Escherichia coli (ETEC) was studied in children without diarrhoea in two remote Aboriginal communities in tropical north-western Australia. Serial surveys of the same individuals during different seasons showed that isolations were much more frequent in the wet monsoonal summer than in the dry winter. All E. coli were isolated from symptomless children aged 5 years or less; in addition, clearance of ETEC carriage without treatment was observed in all individuals within 3 months of isolation. Of the 58 ETEC strains isolated, 40 had either an H32 or an O126 antigen. Five O antigens which have never been associated with ETEC (O2, O41, O71, O77 and O157) were found. A recently proposed system to detect ETEC, using groups of polyvalent antisera, would have detected only 3 out of these 58 ETEC strains.

Antigens, Bacterial↗
PubMed1983

Patterns of intestinal infection in Australian Aboriginal children.

A year-long, prospective study of Aboriginal children with diarrhoea showed a high rate of isolation of bacterial pathogens, viruses and parasites in faecal specimens. Seventeen per cent of patients had enterotoxigenic bacteria in their stools; none of the 132 Aboriginal children without diarrhoea studied at the same time had enterotoxigenic bacteria isolated. Salmonellae and shigellae were also much more common in the diarrhoea group. Bacterial pathogens including enterotoxigenic E. coli and Aeromonas, salmonella, shigella, and campylobacter occurred in 39% of the diarrhoea group but were found in only 4.5% of the controls. Rotaviruses were detected in 12% of children with diarrhoea and in 8% of controls. Intestinal parasites, particularly Giardia lamblia, were present in over 25% of children in each group.

Aeromonas↗
PubMed1983

The microbiology of childhood gastroenteritis: Aeromonas species and other infective agents.

A prospective, 12-month study of 975 non-Aboriginal children with diarrhea and age- and sex-matched children without diarrhea, in Perth, Western Australia, was designed to investigate the significance of enterotoxigenic Aeromonas species as a cause of diarrhea. Enterotoxigenic Aeromonas species were found in the fecal specimens of 10.8% of the patients with diarrhea but in only 0.7% of those without diarrhea. Most Aeromonas species were isolated during the summer. Other important bacterial pathogens included Campylobacter, Salmonella, Shigella, and enterotoxigenic Escherichia coli; rotavirus infections appeared to be much less important in the Western Australian environment. Most of the patients were younger than two years of age and about one-quarter had mixed bacterial and/or viral intestinal infections. Enterotoxigenic Aeromonas species can be identified with 97% accuracy using a simple hemolysin assay which should be considered for use by routine diagnostic laboratories, particularly in children's hospitals.

Aeromonas↗
PubMed1983

Effects of long-term dietary modifications on pancreatic enzyme activity.

The effect of long-term dietary modification on pancreatic exocrine function in rats has been investigated by examining responses to cholecystokinin-pancreozymin stimulation, using a method of direct pancreatic duct cannulation. Residual pancreatic enzyme activity remaining in the whole pancreas following stimulation was also measured. After 6 months of dietary modification, changes in the pancreatic secretions of high-protein- or high-fat-fed animals were similar to those reported in short-term studies in which elevation of trypsin and lipase activity occurred in the pancreas. However, between 6 and 9 months, both volume and amylase activity of pancreatic secretions decreased in animals fed a high-protein diet. At 6 and 9 months, animals fed a high-carbohydrate diet had increased amounts of amylase and decreased trypsin in both pancreatic secretion and homogenate, similar to short-term changes previously reported. High-carbohydrate-fed animals had decreased lipase activity in pancreatic secretions, but lipase activity in pancreatic homogenates was increased, similar to levels found in animals fed a high-fat diet.

Animals↗