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R B Williams

Publications and source records attributed to R B Williams.

At least 19 recordsLinked to original sources
PubMed1992

Hostility during late adolescence predicts coronary risk factors at mid-life.

Hostility, as measured by the Cook-Medley Hostility Scale of the Minnesota Multiphasic Personality Inventory, has been found to predict higher rates of both coronary heart disease and all-cause mortality. To evaluate one mechanism whereby hostility might contribute to health problems, the authors used regression models to determine whether hostility measured in college (1964-1966) predicted coronary risk factors assessed 21-23 years later (1987-1990) in 4,710 men and women. Of this group, 828 had lipids measured (1988-1991). Persons with higher hostility scores in college were significantly more likely at follow-up to consume more caffeine (r = 0.043), to have a larger body mass index (r = 0.055), to have higher lipid ratios (r = 0.092), and to be current smokers (r = 0.069) than those with lower hostility scores during college. Cross-sectional analyses found significant associations of contemporaneous hostility scores with the same four risk factors, as well as with alcohol consumption and hypertension (rs ranging from 0.043 to 0.117). These associations are large enough to have possible public health significance. We conclude that hostility may contribute to health problems through its influences on several coronary risk factors across the adult life span.

Adult↗
PubMed1992

Differences between the anticoccidial potencies of monensin in maize-based or wheat-based chicken diets.

Experiments were carried out to investigate why the anticoccidial ionophore monensin is more potent against the coccidium Eimeria tenella in chickens fed on a maize-based diet (as in the USA) than in chickens fed on a wheat-based diet (as in the UK). The explanation seems to be that the pathogenicity of E. tenella is lower in maize-fed chickens than in wheat-fed chickens, whether monensin is present in the diet or not. Possible reasons for this are suggested. The better survival of maize-fed birds may be partly due to protective effects of the higher concentrations of vitamins A and E derived from their diet. Furthermore, the higher concentrations of niacin and riboflavin in wheat than in maize may enhance coccidial pathogenicity. These opposing factors might combine to cause equivalent infection levels to produce more severe coccidiosis in chickens fed on a wheat-based diet than on a maize-based diet.

Animal Feed↗
PubMed1992

Alpha-tocopherol, lipids and lipoproteins in knee-joint synovial fluid and serum from patients with inflammatory joint disease.

1. We have determined the antioxidant status of synovial fluid and serum of patients with inflammatory joint disease in terms of the biologically active lipid-soluble antioxidant, alpha-tocopherol. Synovial fluid concentrations of alpha-tocopherol were significantly lower relative to those of paired serum samples (P < 0.001). Serum levels of alpha-tocopherol in these patients did not differ significantly from those in control serum. 2. Lower concentrations of cholesterol, triacylglycerol and low-density lipoprotein were also observed in patients' synovial fluid compared with matched serum samples. However, multiple regression analysis of the data indicated that there remained a significant depletion of alpha-tocopherol, which was largely independent of these co-variables, in inflammatory synovial fluid. These findings are consistent with the consumption of alpha-tocopherol within the inflamed joint via its role in terminating the process of lipid peroxidation. 3. Nuclear magnetic resonance spectroscopic analysis of matched inflammatory synovial fluid and serum confirmed lower concentrations of triacylglycerol in synovial fluid together with evidence of a shortened mean triacylglycerol chain length. The latter metabolic difference suggests an increased utilization of triacylglycerols for energy within the inflamed joint.

Arthritis↗
PubMed1992

Accentuated vagal antagonism of beta-adrenergic effects on ventricular repolarization. Evidence of weaker antagonism in hostile type A men.

BACKGROUND: Prior research has suggested a weaker parasympathetic antagonism of sympathetic effects on the heart in type A (coronary-prone) men. To confirm this phenomenon and extend our understanding of it, we investigated the effects of prior muscarinic blockade on the electrocardiogram T wave and other cardiovascular and neuroendocrine responses to isoproterenol in type A and type B (non-coronary-prone) men. METHODS AND RESULTS: Responses to two 5-minute intravenous isoproterenol infusions (0.01 micrograms/kg/min and 0.02 micrograms/kg/min) were evaluated in six type A and six type B men after pretreatment with either dextrose placebo or atropine (1.2 mg). Atropine significantly potentiated T wave attenuation in the recovery period after isoproterenol infusion (0.30 +/- 0.07 mV) compared with placebo (0.54 +/- 0.09 mV, p less than 0.001). Atropine also potentiated the heart rate increase to isoproterenol (39 +/- 3 beats per minute versus 20 +/- 2 beats per minute after placebo). Atropine enhanced decreases in systolic, diastolic, and mean arterial pressures as well as pulse pressure to isoproterenol. Atropine enhancement of many of these responses was increased among subjects with high scores on various hostility/anger scales. Isoproterenol alone produced greater T wave attenuation in type A than in type B men. However, atropine enhancement of T wave attenuation and blood pressure falls by isoproterenol was present only in type B men. CONCLUSIONS: These findings indicate that there is accentuated parasympathetic antagonism of T wave attenuation and blood pressure responses induced by beta-adrenergic stimulation. Relative weakness of this antagonism of sympathetic effects on the heart in hostile type A individuals may contribute to their higher coronary disease risk.

Adult↗
PubMed1992

Identification of patients with coronary disease at high risk for loss of employment. A prospective validation study.

BACKGROUND: Work disability is common in patients with coronary artery disease and adversely affects both economic well-being and quality of life. The purpose of this study was to construct a model to predict premature departure from the work force of patients with coronary disease and to validate this model prospectively in an independent cohort of patients. METHODS AND RESULTS: We enrolled 1,252 coronary disease patients referred for diagnostic cardiac catheterization who were less than age 65, employed, and without prior coronary angioplasty or coronary bypass surgery. Medical, functional, psychological, economic, and job-related variables were measured at the time of baseline diagnostic cardiac catheterization, and all patients were followed for 1 year. Three hundred twelve patients underwent percutaneous transluminal coronary angioplasty (PTCA) within 60 days of catheterization, and 449 had coronary artery bypass graft surgery (CABG) within 60 days of catheterization. The remaining 491 patients were treated with initial medical therapy. Logistic regression was used to develop a multivariable model for predicting 1-year work status in the training sample patients (872 patients enrolled between March 1986 and February 1989). This model was then validated in the independent prospective test sample (380 patients enrolled between March 1989 and June 1990). Eight factors were independent predictors of departure from the work force: lower initial functional status (as assessed by the Duke Activity Status Index), followed by older age, black race, presence of congestive heart failure, lower education level, presence of extracardiac vascular disease, poorer psychological status, and lower job classification. Standard clinical variables provided only 20% of the total predictive information available from the model about follow-up work outcomes, whereas functional measures provided 27%, and demographic and socioeconomic measures provided 45%. In the test sample, the area under the receiver operating characteristic curve for the model predictions was 0.74, compared with 0.80 in the training sample, and model predictions agreed well with observed prevalences of return to work. After adjustment for baseline imbalances, there was no significant difference in 1-year return-to-work rates among the patients receiving initial PTCA or CABG therapy versus initial medical therapy. CONCLUSIONS: Patients with coronary disease who are at high risk for premature departure from the work force can be accurately identified from a combination of medical and nonmedical risk factors. The model developed in this study provides a tool to identify patients at high risk for premature loss from the work force. Such patients may benefit from special multidimensional intervention programs designed to preserve work status. Our data show that revascularization with either PTCA or CABG is not, by itself, sufficient to accomplish this goal.

Angioplasty, Balloon, Coronary↗
PubMed1979

Is there a doctor in the house?

When it is realized that American universities award nearly 50,000 different kinds of doctorates annually, it is little wonder that some should ask, "What is a real doctor?" This paper explores briefly the view which holds that the term "doctor" should be reserved for those whose long years of intensive study and practice in the field of medicine entitles them to this special designation. Attention is also given to the opposing view which argues that the phenomenon of doctoring, in the broad and generic sense, properly encompasses, not alone the field of medicine, but a number of disciplines that seek "to restore to good condition."

Physicians↗
PubMed1978

Location of CNS neurons mediating the blood pressure fall after shock-induced fighting in the rat.

Previous research has demonstrated a fall in systolic blood pressure in the rat measured 2--5 min following shock-induced fighting. This blood pressure fall appears to depend on intact CNS catecholamine neurons. The locus coeruleus is known to supply noradrenergic neuron terminals to much of the brain. In this study, we attempted to identify the location of the CNS catecholamine neurons mediating the blood pressure response to fighting by studying the blood pressure response to shock-induced fighting in locus coeruleus-lesioned and shamlesioned rats. The locus coeruleus-lesioned animals showed a blood pressure increase after fighting on the average across 2 days of testing, while sham-lesioned animals showed a blood pressure decrease after fighting. The difference between the blood pressure responses of the two groups was highly reliable. Since both histofluorescence and biochemical studies indicated that CNS norepinephrine levels were decreased in lesioned as compared to control animals, the findings are interpreted as showing that noradrenergic neurons originating in the locus coeruleus play an important role in mediating aspects of the relationship between fighting behavior and blood pressure response.

Aggression↗
PubMed1978

Endocardial fibrosis in apparently normal infant hearts.

A classification of the histological appearance of the endocardium in infants, and observers' reproducibility tests have been carried out. In a retrospective survey of 262 overtly normal hearts, what is considered to be abnormal thickening of the endocardium was found in 3.4%, and probably significant thickening in 20%. The changes occurred in unexpected home deaths as well as in hospital deaths and the lesions may be a contributing factor in some cot deaths, but a prospective study is required to confirm this.

Endocardial Fibroelastosis↗
PubMed1978

Type A behavior pattern and coronary atherosclerosis.

Previous research has demonstrated an increased rate of clinical coronary heart disease (CHD) events among people who exhibit a "coronary prone" (Type A) behavior pattern. This study was undertaken to determine whether the association between behavior pattern Type A and CHD might be extended beyond clinical CHD events to include also the coronary atherosclerotic process. In addition to usual clinical evaluation, 156 consecutive patients referred for diagnostic coronary angiography were independently assessed on the basis of a structured interview and assigned a rating of Type A, Type B, or Type X (indeterminate). Traditional physiologic factors--age, sex, cholesterol and cigarette smoking--were found to correlate with atherosclerotic disease. Type A patients were found in increasing proportions among groups of patients with coronary occlusions of moderate to severe degree compared with patients with only mild occlusions. This increasing proportion of Type A patients with increasing disease severity remained significant, even when age, sex, blood pressure, serum cholesterol level and cigarette smoking history were all simultaneously covaried. These findings suggest that, independently of traditional risk factors, behavior pattern Type A may contribute to the risk of clinical CHD events via effects on the atherosclerotic process.

Adolescent↗
PubMed1977

6-hydroxydopamine destruction of central adrenergic neurones prevents or reverses developing DOCA-salt hypertension in rats.

The role of brain catecholaminergic neurones in the pathogenesis of DOCA-salt hypertension in the rat was investigated by selective depletion of central catecholamines using intraventricular or intracisternal administration of 6-hydroxydopamine (6-OHDA). Only the intraventricular injections prevented the development of hypertension. In addition, intraventricular 6-OHDA reversed the hypertension produced by two weeks but not six weeks of DOCA-salt treatment. The ability of intraventricular injections of 6-OHDA to prevent or reverse DOCA-salt hypertension while intracisternal injections do not, appears to be related to the greater depletion of brain catecholamines produced by the intraventricular injections. Only in the spinal cord and in the locus coeruleus were the norepinephrine contents depleted equally by either injection route. These findings suggest that central catecholaminergic neurones other than those originating in the locus coeruleus or descending in the spinal cord are important in the initiation, but not in the long term maintenance, of DOCA-salt hypertension. The influence of the central catecholamine neurons involved in the development of DOCA-salt hypertension might be mediated neurally via nonadrenergic pathways or hormonally via the brain-pituitary-endocrine system.

Adrenergic Fibers↗
PubMed1977

The enhancement by dietary zinc deficiency of the susceptibility of the rat duodenum to colchicine.

1. The incidence of colchicine-induced lesions in the germinal epithelium oof the rat duodenum was studied in young rats in an early stage of zinc deficiency and in their pair-fed controls. At both dose levels of colchicine used, a marked increase in the amount of cell damage was observed in the duodenum of Zn-deficient rats as compared with the pair-fed, control (Zn-supplemented) rats. 2. No statistical interaction between Zn and colchicine was demonstrable, and no lesions were found in the duodenum of animals that had not been treated with colchicine. 3. The results are discussed in relation to the effects of Zn deficiency in animals and the possible involvement of Zn in the maintenance of the integrity of microtubular structures.

Animals↗