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Biomedical subjects

R J West

Publications and source records attributed to R J West.

At least 37 records · Page 2Linked to original sources
PubMed1991

Role of endoscopic retrograde cholangiopancreatography after orthotopic liver transplantation.

Twelve of 178 (7%) liver transplant patients underwent endoscopic retrograde cholangiopancreatography (ERCP) after transplantation. The indications for ERCP were persistent or late onset cholestasis, recurrent cholangitis, and suspected biliary leaks or strictures. The time between transplantation and ERCP ranged from 44 to 330 days (median 153 days). Biliary complications diagnosed by ERCP included biliary sludge in the form of casts, calculi, or debris (n = 7); bile leaks (n = 2); a biliary stricture (n = 1), and complete biliary obstruction (n = 1). One patient had a normal cholangiogram after transplantation. Biliary sludge was detected by ultrasound before ERCP in only one of six patients. Eight patients underwent endoscopic papillotomy, followed by clearance of biliary sludge in four and dilatation of a biliary stricture in one. Two patients bled after papillotomy but neither required surgical intervention. At a median follow up of 1.2 years (range 0.5-2.8 years), nine patients are well and three have died. ERCP provides both accurate diagnosis of biliary complications after liver transplantation and treatment that obviates the need for additional surgery in selected patients.

Adult↗
PubMed1990

Nicotine pharmacodynamics: some unresolved issues.

This paper focuses on some issues in the field of nicotine pharmacodynamics in which widely held suppositions have outstripped the supporting evidence. It considers how far the view that nicotine acts as a stimulant in low doses and as a sedative in higher doses is supported by the data and concludes that within the range of doses ingested by cigarette smokers, only stimulant actions have been reliably observed. It examines evidence for the view that nicotine improves ability to sustain attention and concludes that a positive effect of nicotine not attributable to relief of a withdrawal deficit has yet to be demonstrated. Finally, it considers the issue of physiological tolerance and argues that ideas concerning a role for chronic tolerance in nicotine dependence have yet to be supported empirically. Despite advances in our understanding of nicotine's effects in recent years there is still much work to be carried out before fundamental issues underlying its addictive potential can be resolved.

Animals↗
PubMed1990

Bioavailability of a new sustained-release theophylline capsule in fasted and non-fasted healthy subjects: single and multiple dosing studies.

Eighteen healthy, non-smoking, adult volunteers participated in single and multiple dose three-way crossover studies to evaluate a sustained-release, pellet-filled capsule of theophylline, Austyn. The effect of food on the bioavailability of the sustained-release capsule was investigated by administering 300 mg single doses of Austyn, with a high-fat meal and without food and a divided 300 mg dose of the reference product Elixophyllin elixir, given after fasting. Plasma theophylline concentrations were measured by fluorescence polarization immunoassay (FPIA) which had been validated against HPLC. The single dose study data showed that there were no significant differences (n = 18, ANOVA, p greater than 0.05) between the three regimens with respect to AUC0-infinity values (mg h l-1), (mean +/- SD); Elixophyllin fasting = 97.1 +/- 33.7, Austyn with food = 90.9 +/- 31.3, Austyn fasting = 91.2 +/- 33.8. Similarly, multiple dosing with rapid-release Nuelin tablets, Austyn capsules, and sustained-release Theo-Dur tablets demonstrated that there were no significant differences between regimens with respect to AUC0-24h, AUC0-12h, and AUC12-24h values calculated from the steady-state concentrations (5th day, 24 h sampling). However, the percentage fluctuation at steady-state over the total blood sampling period was significantly less for treatment with the sustained-release capsule. Austyn, compared with the sustained-release tablet, Theo-Dur (Austyn = 36.7 +/- 13.7 per cent, Theo-Dur = 53.1 +/- 14.1 per cent). The results of the single and multiple dose studies indicate that Austyn capsules demonstrate complete bioavailability, and good controlled release characteristics not influenced by concomitant intake of a high-fat meal and with no evidence of dose dumping.

Adult↗
PubMed1989

Hepatic vein webs and resistant ascites. Diagnosis, management and implications.

Webs of hepatic veins have been rarely described. Two patients presented with intractable ascites in whom hepatic venography demonstrated this unusual finding. Liver biopsies from both patients showed variable patterns of perivenular fibrosis. Transvenous balloon dilatation of the web was effective in abolishing the pressure gradient across the obstruction and improving hepatic venous outflow. Both patients showed a dramatic clinical improvement following the procedure, with complete resolution of ascites in one patient and considerable improvement in the other with symptoms not recurring over 18 months of follow-up. The histological features that help to distinguish hepatic venous outflow obstruction from other causes of perivenular fibrosis are described.

Adult↗
PubMed1989

Severity of withdrawal symptoms as a predictor of outcome of an attempt to quit smoking.

In 227 smokers' clinic clients who managed at least one week of abstinence, ratings of withdrawal symptoms were used to predict subsequent return to smoking. Depression, time spent with urges to smoke, and difficulty not smoking during the first week of abstinence were significantly associated with lapse back to smoking during the second week. Depression and difficulty not smoking during the second week significantly predicted smoking status during the third week. No withdrawal symptoms during the third week were associated with a return to smoking during the fourth week. The predictive power of withdrawal symptoms was over and above that of smoke intake and dependence. The findings provide some support for the view that reduction of withdrawal symptoms may be a worthwhile target in programmes for helping smokers to quit.

Adult↗
PubMed1989

Nicotine intake in young smokers: longitudinal study of saliva cotinine concentrations.

Smoking habits and smoke intake were studied over three consecutive years in 197 girls, initially aged 11 to 14 years. Saliva cotinine concentrations in girls who were smokers throughout the three years increased over each year of the study, the greatest increase occurring during movement from occasional to daily smoking. Cigarette consumption also increased over the two years. For a group of continuing daily smokers (n = 23), inhalation of smoke per cigarette as indexed by the ratio of cotinine concentration to average daily cigarette consumption did not change over time. Cotinine concentrations in 16 girls who were smoking on a daily basis within a year of starting to smoke suggested the early development of inhalation. Our findings suggest that young smokers learn to inhale cigarette smoke very early in their smoking careers, that further increases in smoke intake mainly reflect increased cigarette consumption, and that the pharmacological effects of nicotine are already important in reinforcing their smoking.

Adolescent↗
PubMed1987

Cardiovascular and subjective effects of smoking before and after 24 h of abstinence from cigarettes.

Cigarette-induced changes in heart rate, skin temperature and subjective state were measured during the course of a normal smoking day and on smoking after 24 h abstinence in 21 smokers. Heart rate was not affected by smoking a test cigarette during the normal day's smoking, but after 24 h abstinence smoking a cigarette caused an average increase of 14 beats per min. Skin temperature, on the other hand, was reduced by smoking a cigarette under both conditions. Subjective effects of smoking were experienced only after the period of abstinence. The most common was dizziness, but nausea and other effects were also reported. Cigarette-induced changes in heart rate and skin temperature were positively correlated with each other, and the rise in heart rate after abstinence correlated positively with the strength of the subjective response. The results are discussed in terms of similarities and differences between different physiological systems in tolerance to the effects of nicotine.

Adult↗
PubMed1987

Time course of cigarette withdrawal symptoms during four weeks of treatment with nicotine chewing gum.

Ratings of withdrawal symptoms were obtained from 52 Smokers Clinic clients who abstained throughout a four week group treatment programme involving use of nicotine chewing gum. Mean ratings of irritability, depression, hunger, restlessness, and inability to concentrate were significantly higher in the first week of abstinence than at baseline, although only a minority of smokers experienced severe withdrawal symptoms. Disturbance of mood and concentration returned to baseline within four weeks while increases in hunger persisted. The average amount of time spent with the urge to smoke started to decline early in treatment, but the average strength of urges and overall difficulty not smoking did not decline until the fourth week. At the end of treatment 35% were still experiencing strong urges to smoke and 23% reported finding it difficult keeping themselves from smoking. The findings have practical implications for preparing smokers for cessation with the aid of nicotine gum.

Adult↗
PubMed1987

Bacterial tracheitis in Down's syndrome.

Four children with Down's syndrome and bacterial tracheitis are described. In three the infection was due to Haemophilus influenza. In patients with Down's syndrome presenting with stridor tracheitis should be considered and appropriate treatment started.

Child↗
PubMed1986

Respite care on a children's ward.

In March 1984 a short term respite care facility for handicapped children was opened in a children's ward catering primarily for acute medical and surgical problems. The facility was based on a four bedded room designed so that if beds became short in the main ward it could revert immediately to the care of acutely sick children. Three nurses were appointed specifically to staff the facility, the nursing budget for the rest of the ward being reduced proportionately. Conversions were funded by charities and some of the conversion work done by volunteers. The main users were totally dependent children aged under 5 with severe mental and physical handicaps. Parents found the service invaluable, and in addition to planned admissions it was usually possible to accept a child at short notice--for example, when some domestic crisis occurred. Only very rarely was admission impossible because of the needs of acutely ill children. A short term respite care facility not only helps parents cope and may provide beneficial experience for a handicapped child but is also a useful training ground for medical students and junior staff.

Child↗