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R W Motson

Publications and source records attributed to R W Motson.

54 records · Page 3Linked to original sources
PubMed1984

A method for studying the actions of drugs on motility of vascularly perfused segments of human colon.

The isolated, vascularly perfused human colon is a novel method for investigating drug action on this organ. Measurement of the integrated motility of the muscle layers and the facility for administering drugs via the blood supply represent advances over muscle strip studies. Viability of the specimens was improved by addition of Dextran 70 to the perfusion fluid to minimise oedema. Changes in motility were recorded with small, water-filled intraluminal balloons. Measurements were made for 10 min periods immediately before and after drug administration using a linear displacement method. Both neostigmine (1.0-3.0 micrograms/ml) and bethanechol (1.0-5 micrograms/ml) significantly increased motility of the segments, while morphine (10-50 micrograms/ml) did not.

Bethanechol Compounds↗
PubMed1983

Results of Parks operation for faecal incontinence after anal sphincter injury.

Parks operation for faecal incontinence was performed on 97 patients with total loss of anorectal control due to injury. All had sustained complete division of the anal sphincters as a result of trauma, anal surgery, or obstetric tears and either were incontinent or had been given a colostomy. In all patients the divided sphincters were repaired using an overlapping technique; in 93 the repair was protected by a temporary defunctioning stoma. There was no operative mortality. Continence was completely restored in 65 (78%) and improved in a further 11 (13%) of the 83 patients assessed from four to 116 months postoperatively. Minor complications which did not affect the eventual clinical outcome occurred in 23 patients. Factors associated with failure of the operation included breakdown of the repair in the early postoperative period, fistula, and pelvic floor neuropathy. The results show that even after severe injury to the sphincters surgical reconstruction can restore continence in most patients.

Adolescent↗
PubMed1983

Peranal repair of rectoprostatic fistula.

Rectoprostatic fistula is a rare complication of prostatectomy by any route including transurethral resection. Occasionally a fistula occurs congenitally or as a result of pelvic trauma. Five patients with rectoprostatic fistulas (4 post-prostatectomy, 1 traumatic) were repaired peranally using a full-thickness local flap of anterior rectal wall. The repair was protected by sigmoid loop colostomy. Primary healing occurred in all 5 patients. Anal and urinary continence are normal following colostomy closure in 3 patients. Two patients died of unrelated causes before colostomy closure.

Adult↗
PubMed1983

Fistulae involving rectum and urethra: the place of Parks's operations.

Twenty-five rectovesical and rectourethral fistulae were treated over an 18-year period in which various methods for closing the rectal side of the fistula were developed, ultimately with two techniques using the full thickness of intestine. As a result of these operations the management of the urethral and vesical side of the fistulae became a relatively simple problem to which standard techniques could be applied.

Adult↗
PubMed1981

Dissolution of common bile duct stones.

Retained common duct stones can now be treated by a number of non-operative techniques, including dissolution by cholesterol solvents, simple irrigation, stone extraction via the T tube tract and by endoscopic sphincterotomy. This paper reviews the various solvents available for stone dissolution and its physicochemical basis. When a retained stone is found simple irrigation with saline will be successful in about 50 per cent of patients. If this fails, stone extraction via the T tube tract or by endoscopic sphincterotomy are now the methods of choice, with a 90--95 per cent chance of success. Stone dissolution by cholic acid is slow and is only successful in about 60 per cent of patients but can be of value when stone extraction is unavailable or unsuccessful.

Bile Acids and Salts↗
PubMed1981

Effect of chronic changes in rate of enterohepatic cycling on bile acid kinetics and biliary lipid composition in the rhesus monkey.

Although several studies have demonstrated an inverse relationship between size of the bile salt pool and frequency of enterohepatic cycling, most such data have been obtained in conditions where control of cycling frequency was not possible. In this study, we diverted bile from the bile duct of Rhesus monkeys into a reservoir and returned it to the duodenum at varying rates, a model that mimicked differences in frequency of gallbladder emptying. As cycling frequency increased from 1 to 8 cycles/day, size of the bile salt pool decreased from 1756 microM to 369 microM. Changes in fractional turnover rate parallelled changes in cycling frequency. The relative composition of the biliary lipids remained the same throughout the range of cycling frequencies. These data show that direct manipulation of cycling frequency had the predicted effects on other parameters of the enterohepatic circulation but did not give rise to lithogenic bile.

Animals↗
PubMed1980

Operative choledochoscopy: experience with a rigid choledochoscope.

The use of a choledochoscope after exploration of the common bile ducts should minimize the occurrence of retained common bile duct stones. Experience gained at 50 endoscopies with a rigid choledochoscope is reviewed. In 7 cases stones or debris were found remaining in the bile duct. In one case an unsuspected neoplasm was demonstrated and in another a suspected neoplastic stricture was confirmed. In the remaining 41 cases choledochoscopy showed the ducts to be free of stones. Postoperative cholangiography demonstrated a retained stone in 2 cases. There were 2 deaths in the series. The experience of other authors with rigid and flexible scopes is reviewed.

Adult↗
PubMed1979

Easier operative cholangiography.

A simplified technique for operative cholangiography utilizing a cholangiogram clamp is described. The technique has been used without complications in over two hundred cholecystectomies and greatly reduces the time taken to perform an operative cholangiogram.

Cholangiography↗
PubMed1978

The effect of short-and long-term corticosteroid treatment on sleep-associated growth hormone secretion.

Eight healthy medical studients and four renal transplant patients had blood sampled two or three times hourly throughout EEG monitored nocturnal sleep. This was carried out on the healthy subjects for a total of 12 nights without medication (control nights asleep), a total of 12 nights following 40 mg of flucortolone the previous morning, and a total of 6 nights with similar blood sampling when sleep was prevented (control nights awake). Four renal transplant patients who were receiving long-term therapy with prednisolone were similarly studied (total of 7 nights asleep). Circulating corticosteroid and growth hormone (GH) levels were determined. A peak of GH was seen during the first 2 h of sleep on the control nights when slow-wave sleep predominated. The GH peak was absent on the control nights awake. The pattern of plasma corticosteroid levels was identical during control nights asleep and awake. Both single-dose and chronic corticosteroid administration inhibited the GH peak associated with slow-wave sleep. Chronic corticosteroid therapy, but no single-dose administration in the morning, suppressed the circadian rise of plasma corticosteroids which normally occurs late in sleep.

Adult↗
PubMedDate not supplied

MRC CLASICC trial.

Explore the source record for details and available documents.

Colectomy↗
PubMedDate not supplied

Pharmacokinetics of iopanoic acid in the rhesus monkey: biliary excretion, plasma protein binding and biotransformation.

A dynamic infusion method, originally developed for the pharmacokinetic studies of Iodoxamic acid, was applied to the kinetic studies of the biliary excretion of another cholecystographic agent, iopanoic acid. This dynamic method has an important advantage in that the pharmacokinetic parameters involved in the hepatic uptake or biliary excretion can be evaluated from a single infusion experiment. Using the equilibrium dialysis technique, iopanoic acid was found to be highly bound to the plasma proteins. A linear relationship was found when the logarithm of unbound plasma concentration of iopanoic acid was plotted vs. the logarithm of its blood concentration. When the biliary excretion rates of iopanoic acid were fitted by a computer to the Michaelis-Menten equation against its unbound plasma concentration, the average Vm value was found to be 0.85 micron/kg/min and the average Km value was found to be 0.253 micron. Iopanoic acid was found to exist in monkey blood as unchanged species and in the bile mainly as the ester glucuronide.

Animals↗