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Biomedical subjects

R Wilson

Publications and source records attributed to R Wilson.

At least 649 records · Page 36Linked to original sources
PubMed1985

Transient ischemia in angina pectoris: frequent silent events with everyday activities.

To help characterize episodes of transient myocardial ischemia, 80 patients with chronic stable angina and evidence of obstructive coronary disease were studied by ambulatory electrocardiographic (ECG) monitoring outside the hospital to detect both symptomatic and asymptomatic episodes of ST-segment depression. In addition, patients were tested on an outpatient basis by means of positron emission tomography to assess regional coronary blood flow under different conditions. All patients showed ECG evidence of transient ischemia, with or without symptoms, while active outside the hospital. In-hospital testing showed that symptomatic and asymptomatic disturbances in regional coronary blood flow occurred with normal everyday activities and were not caused by physical exertion involving marked increases in heart rate and blood pressure. Most of these provocations were followed by a decrease in coronary blood flow in a poststenotic segment of myocardium and, like the ischemic events monitored out of hospital, the majority were silent. Many of these features characterizing the activity of ischemic heart disease may not be apparent from a patient's anginal history or results of hospital diagnostic testing.

Activities of Daily Living↗
PubMed1985

Risks posed by various components of hair dyes.

In this study, I calculated the risks presented by the use of several chemicals that are or were used in hair dyes and for which a good animal bioassay is available. The risks were calculated using the carcinogenic potency measure used in the National Cancer Institute bioassays concerning the exposure of rats and mice to these chemicals. The procedure used was that previously discussed by Zeise et al.; it is similar to, but logically more complete, than those normally used by Food and Drug Administration (FDA) and the Environmental Protection Agency (EPA). The expected value of the risk for the worst dye that has now been discontinued is as high as that of smoking 6 cigarettes in a lifetime; the 95th percentile gives a risk equivalent to that of smoking 120 cigarettes in a lifetime or 2 per year. Even when the upper limits of carcinogenic potency of the untested chemicals are employed using correlations with toxicity, the estimated risk remains small.

Animals↗
PubMed1985

Abnormal nasal mucociliary clearance in patients with rhinitis and its relationship to concomitant chest disease.

Nasal mucociliary clearance was measured using a saccharin technique in 172 patients with perennial rhinitis (76 also had asthma) and in 121 patients with chronic infected rhinosinusitis (40 had asthma, 35 had bronchiectasis). All patient groups had significantly longer mean nasal mucociliary clearance times than that of a group of healthy subjects. Grossly prolonged clearance (greater than 60 minutes) occurred in significantly more patients with the clinical syndrome of chronic infected rhinosinusitis and bronchiectasis than in the syndromes of chronic infected rhinosinusitis with or without asthma, and perennial rhinitis with or without asthma. The abnormal clearance was shown not to be due to an intrinsic ciliary defect by in vitro examination of nasal cilia but probably to be due to a combination of mucus and ciliary factors in vivo.

Adolescent↗
PubMed1985

Buspirone: anxiolytic?

Sixty (60) out-patients with DSM III generalized anxiety disorder were treated after a 1-week placebo washout in a 4-week double-blind study with buspirone, diazepam and placebo; after which they were withdrawn abruptly from medication or assigned to a 2-week period of placebo. The HAM-A score was significantly lower in the diazepam group at week 2 (p less than .02) and the buspirone group at week 3 (p less than .04) as compared to the placebo group. A similar pattern was evident in the female group, but not in the male group. Dizziness was the most prominent adverse effect in the buspirone group, whereas the diazepam group had more adverse effects including sedation, fatigue, dizziness and impaired concentration. Withdrawal symptoms were more evident in the diazepam group than the buspirone group.

Adult↗
PubMed1985

Uptake and vascular transport of ingested aflatoxin.

The uptake and vascular transport of abomasally instilled aflatoxin B1 (AFB1) was investigated in sheep. Aflatoxin uptake was compared with that of palmitate, a water-insoluble oil known to be absorbed into the intestinal lymphatic drainage which bypasses the liver to enter the peripheral vascular circulation via the thoracic duct. After instillation into the abomasum, aflatoxin was detected in inferior vena cava blood within 30 min, while palmitate was not detected in vena cava blood at any time. Palmitate was detected in thoracic duct lymph after about 2 h. More than 95% of the palmitate in lymph was associated with the chylomicron fraction, while aflatoxin in either plasma or lymph was not detectably associated with any of the circulating lipoproteins. In addition, aflatoxin did not partition into plasma or lymph lipoproteins in vitro. Toxic lipophilic xenobiotics, such as benzo(a)pyrene and polychlorinated biphenyls (PCBs) do partition into lipoproteins, are absorbed into the intestinal lymphatic drainage, bypassing the liver to enter the peripheral vascular circulation directly, and are not specifically hepatotoxic. These data suggest that the mode of aflatoxin absorption from the gastrointestinal system results in its immediate transport to the liver, which may contribute to aflatoxin hepatotoxicity.

Aflatoxin B1↗
PubMed1985

Immune hepatitis B plasma procurement.

The requirement for hepatitis B immunoglobulin for passive immunisation persists despite the availability of a safe hepatitis B vaccine, and there is therefore a need for immune plasma for immunoglobulin production. We have screened a large number of blood donors to identify potentially suitable hepatitis B immune plasma donors. The logistics of this have been examined, and the programme was found to be inefficient and labour-consuming. A suitably designed programme of active immunisation with hepatitis B vaccine should provide a more effective means of obtaining plasma.

Blood Donors↗
PubMed1985

Effect of bacterial products on human ciliary function in vitro.

Ciliary activity protects the respiratory tract against inhaled particles, including bacteria, by transporting them trapped in mucus towards the pharynx. We have studied the effect of bacteria (Haemophilus influenzae, Staphylococcus aureus, and Pseudomonas aeruginosa) on human nasal cilia, measuring their in vitro ciliary beat frequency by a photometric technique. Supernatant fluids were obtained from 18 hour broth cultures by centrifugation alone, by filtration, and by lysis. Supernatants obtained from Ps aeruginosa and H influenzae caused a significantly lower ciliary beat frequency than controls (broth alone). Slowed cilia were dyskinetic and at times of maximal slowing ciliostasis occurred in some areas of the epithelium. A dose related effect was demonstrated. Abrogation of cilioinhibitory properties was achieved by heating the lysate to 56 degrees C for 30 minutes and by allowing the filtrate to stand at 37 degrees C for 120 minutes. Staphylococcal products were not cilioinhibitory. It is concluded that Ps aeruginosa and H influenzae release a factor (or factors) which causes slowing of human nasal cilia in vitro. The role of this factor in the pathogenesis of infection is discussed.

Cilia↗