Biomedical subjects
Publications and source records attributed to R Taylor.
The assumption that insulin binding to monocytes reflects that of insulin binding to adipocytes has been examined. In normal, diabetic, thyrotoxic and cirrhotic subjects no correlation was observed between monocyte and adipocyte insulin binding. Extrapolation is not justified from monocyte binding data to conclusions about insulin-sensitive tissues.
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Streptozotocin-induced diabetes mellitus in the rat results in a 30% decrease in serum amylase and an 80% decrease in pancreatic amylase levels. Pancreatic trypsinogen levels decrease 50% whereas pancreatic lipase levels increase 30%. Plasma cyclic nucleotide levels (cAMP and cGMP) increase 40-100%, urine cyclic nucleotide levels decrease 75-99%, but pancreatic cyclic nucleotide levels are unchanged. Short-term insulin treatment restores pancreatic amylase and trypsinogen levels to normal but has no effect on serum amylase or pancreatic lipase levels. Plasma cAMP levels decrease 20% toward normal during insulin treatment, but no other effects on cyclic nucleotide levels occur. These data confirm the profound but reversible effect of experimental diabetes mellitus on pancreatic secretion of amylase and trypsinogen. The results suggest that cyclic nucleotides do not play a direct role in the generation of pancreatic exocrine deficiency in diabetes mellitus or its reversal by insulin.
We investigated, by radionuclide ventriculography, left ventricular function in 10 fit elderly men and in 11 young volunteers. During exercise in the young subjects left ventricular ejection fraction (LVEF) rose from 63 +/- 3 to 73 +/- 1 (P less than 0.005) and end systolic volume (ESV) fell from 48 +/- 6 to 38 +/- 5 ml (P less than 0 +/- 0.005) but were unchanged in the elderly (57 +/- 3 to 55 +/- 3 and 57 +/- 6 to 64 +/- 7 ml, respectively (NS). End diastolic volume (EDV) did not change in either group; stroke volume rose significantly only in the younger subjects, cardiac output rose in both groups but less in the elderly (5 +/- 0.5 to 12 +/- 1 vs 6 +/- 0.5 to 18 +/- 11 min-1). We conclude that this data lend support to the hypothesis that increasing age is associated with reduced left ventricular contractile performance.
The immunocompetence of the following patient groups was compared using peripheral blood mononuclear cells in a variety of in vitro assays: controls (84); hemodialysis patients (32); kidney transplant recipients without cancer (172), and those with skin cancer (18). The in vitro functions assayed were blastogenic responsiveness to phytohemagglutinin (PHA), concanavalin A (Con A), pokeweed mitogen, allogeneic lymphocytes, and two cocktails of bacterial, viral, and fungal antigens; cytotoxic functions assayed were spontaneous cell-mediated cytotoxicity (SCMC) and antibody-dependent cell-mediated cytotoxicity (ADCC). Compared with control subjects, hemodialysis patients showed depressed responsiveness to one antigen cocktail only. Transplant patients with no cancer showed uniformly depressed responsiveness to PHA and allogeneic lymphocytes and reduced SCMC and ADCC activity up to 12 years after transplant; responsiveness in these patients to the two antigen cocktails, after initial depression, recovered by 3 years after transplant to exceed control values. The group of 18 transplant recipients with skin cancer, when compared with transplant recipients with no cancer at a comparable period after transplant, showed similar depression of SCMC and ADCC activity, but significantly greater depression of responsiveness to PHA (P less than 0.01), allogeneic lymphocytes (P less than 0.05), and the 2 antigen cocktails (P less than 0.05).
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Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
A population survey in 1982 has confirmed that Nauruan adults suffer from an extremely high prevalence of Type 2 (noninsulin-dependent) diabetes mellitus. The crude population prevalence of Type 2 diabetes was 24%. Abnormal glucose tolerance (impaired glucose tolerance and diabetes) was present in over 40% of the adult population and exceeded 80% in both sexes after the age of 55 yr. Diabetic retinopathy was present in 24% of diabetic patients, confirming that this Micronesian population is susceptible to the microvascular consequences of hyperglycaemia. Subjects with impaired glucose tolerance had a prevalence of retinopathy three times that of normal subjects, though the difference did not reach statistical significance. Prevalence of retinopathy was substantially higher in diabetic patients than either normal subjects or those with impaired glucose tolerance.
The frequency distribution of log plasma glucose concentrations in certain populations show two distinct subgroups--a non-diabetic group and a hyperglycaemic group--when suitable methods of distributional analysis are used. These two groups show up as a double peak (bimodality) in the best-fit frequency distributions of log plasma glucose, and the separation or cut-off point where the two curves intersect, gives an indication of the plasma glucose level at which diabetes could be diagnosed. Venous plasma glucose concentrations 2 hr after a 75 g oral glucose load were determined in the urban Polynesian population of Western Samoa, in subjects aged 20 yr and over. Bimodality was evident in subjects over 35 yr of age in both sexes, but for the younger age groups the frequency distribution of log plasma glucose follows the usual unimodal Gaussian curve. The data show that among these Polynesians, as with Pimas and Nauruans, the frequency distribution of log plasma glucose concentrations can be used to separate the population into normal and hyperglycaemic groups.
Mortality and hospital admissions due to cardiovascular diseases and diabetes mellitus have been increasing in Fiji steadily over the past 20 years. These diseases were present more frequently in the Indian than the Melanesian population of Fiji, but recently the steepest rise in prevalence rates occurred among the Melanesian population. The underlying conditions that contributed most to increasing mortality and morbidity were hypertension and diabetes mellitus. In 1978, the proportional mortality from diabetes mellitus was 6.0% (9.0% in persons aged >/= 40 years), and that from cardiovascular diseases was 30.3% (39% in those aged >/= 40 years). Ischaemic heart disease was the main cause of mortality and morbidity among the Indian population. This analysis of mortality and morbidity data is supported by the findings of a population survey, which showed that the prevalence rates of diabetes and hypertension in 1980 among urban Melanesians were similar to those among Indians. Urbanization and a modern life-style seem to play an important role in determining the disease pattern in Fiji, which is following the patterns in many industrial countries.
The non-communicable diseases, which include hypertension, diabetes (adult onset type), coronary heart disease, chronic bronchitis and certain cancers (especially those of the lung and bowel) are major public health problems in the adult populations of many Pacific nations undergoing "modernization" of their way of life. Programmes for the prevention and control of these conditions have become more feasible in the Pacific in recent years because of increased awareness of the magnitude and the nature of the problem, and because of important conceptual breakthroughs. Primary prevention will play a cardinal role in such programmes. Secondary prevention, using a conventional therapeutic approach through the primary care system, will also be used, especially for hypertension. Prevention and control programmes against these diseases in the Pacific are in the process of development, and the prospects and constraints in each country will have to be individually and carefully assessed.
To determine whether the island of Niue would be a suitable location to evaluate the efficacy of hepatitis B vaccine, the prevalence of hepatitis B infection in the adult population was studied. Sera were collected from 1147 of 1244 residents above the age of 20 years, and tested for the presence of hepatitis B surface antigen (HBsAg) and specific antibody to the surface and core antigens (anti-HBs and anti-HBc) by solid-phase radioimmunoassay (SPRIA). Hepatitis B was found to be hyperendemic; 11.9% of those tested were found to be carriers of HBsAg and an additional 84% had detectable levels of anti-HBs or anti-HBc indicative of current or past infection. In this population HBV infection appears to occur early in life as the peak prevalence of serological markers was found in young adults. The almost universal infection of the population, their high rate of compliance with the study and the relatively high birth rate indicate that Niue would be a suitable location to evaluate methods of preventing hepatitis B infection.
Diagnosis of TMJ complaints is a complex and difficult task. To better define treatment procedures a firm diagnosis must be established. Radiographs are an aid in confirming diagnosis of TMJ abnormalities. This article has discussed six basic TMJ abnormalities and suggested the optimal radiographic technique for confirming each specific abnormality. Because transmission techniques can only confirm radiographic changes, emission techniques should be considered to evaluate TMJ pathologic activity in early disease prior to definitive bony change. The following can be concluded: 1. In specific TMJ abnormalities, specific emission or transmission radiographs are useful for confirmation. Early definition of all TMJ osseous activity is better defined by emission techniques; while chronic disturbances cause structure change, which is best seen in transmission techniques. 2. Superimposition, angular distortion, reproducibility, and definition of cartilaginous structures (for example, the meniscus) are limitations of transmission techniques. These limitations can be improved by tomography, cephalometric-corrected tomography, computer-assisted tomography, and arthrography of the TMJ. 3. In emission technology structural definition as seen in transmission techniques is lost, while visualization of bone reactivity as seen in early disease is gained.
As the preventive approach gains ground in the care of the elderly there is increasing interest in screening or case-finding. Given the impracticability of visiting all those over a certain age, most GPs and health visitors concentrate on those considered to be at greatest risk of medical and social deterioration. This paper draws on data from a random sample of the elderly population of Aberdeen to examine the nature and extent of 'risk' experienced by those falling into a number of conventionally defined risk groups. It shows that few of these groups are comprehensively disadvantaged and most are inefficient for selective case-finding. An alternative approach based on answers to a carefully selected set of screening questions is shown to be more efficient, and suggestions are offered for further improvements.
An epidemiologic survey of the whole adult Micronesian population of Nauru in the Central Pacific conducted in 1982 has confirmed that Nauruans, along with Pima Indians, suffer the highest rate of abnormal glucose tolerance yet recorded. To establish the morbid effects of hyperglycemia in this population, all responders to the diabetes survey were concurrently examined for diabetic retinopathy. In diabetic subjects, the crude prevalence of retinopathy was 24%. Specific rates were determined at various levels of the following characteristics: age, two-hour post-load plasma glucose, body mass index, duration of diabetes, and systolic blood pressure. Prevalence was found to rise with increasing two-hour plasma glucose and duration, to fall with increasing body mass index, and to have a quadratic relationship with age and systolic blood pressure. The multiple logistic regression model was used to determine whether the selected characteristics were significant in increasing the risk of retinopathy. Body mass index and systolic blood pressure did not contribute significantly to this risk after controlling for age. Increasing two-hour plasma glucose significantly increased the risk of retinopathy, and duration of disease was the strongest predictor variable. This study shows that the consequences of hyperglycemia in this Micronesian population are comparable to those already documented in European and American Indian communities.
Rural-urban and ethnic comparisons of impaired glucose tolerance and diabetes mellitus were made in the biracial population of Fiji in 1980. No statistically significant differences existed in age-standardized impaired glucose tolerance prevalence between rural and urban groups or between Melanesians and Indians. The age-standardized prevalence of diabetes in the rural Melanesian male population was one-third that of the urban male population (1.1 vs. 3.5%). In females, there was a sixfold rural-urban difference (1.2 vs. 7.1%). By contrast, rural and urban Indians had similar rates (12.1 vs. 12.9% for males; 11.3 vs. 11.0% for females). Standardization of two-hour plasma glucose for age and obesity did not eliminate the rural-urban difference in plasma glucose concentration for Melanesian males and females. The results in Melanesians confirm previously reported rural-urban diabetes prevalence differences, and suggest that factors other than obesity, such as differences in physical activity, diet, stress, or other, as yet undetermined, factors contribute to this difference. The absence of a rural-urban difference in diabetes prevalence in Indians may suggest that genetic factors are more important for producing diabetes in this ethnic group, or that causative environmental factors such as diet operate similarly upon both the rural and the urban populations.