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Biomedical subjects

L T Welch

Publications and source records attributed to L T Welch.

At least 19 recordsLinked to original sources
PubMed1979

Uropharmacology: X. Central nervous system stimulants and depressants.

Several drugs that are utilized primarily for their effects on the central nervous system also affect lower urinary tract function. Most of these effects are produced by the action of these drugs on adrenergic and cholinergic receptors or by direct action of lower urinary tract musculature. Central nervous system stimulants and depressants which are known to affect the storage or evacuation role of the lower urinary tract are discussed.

Amphetamines↗
PubMed1978

Uropharmacology: VII. Ganglionic stimulating and blocking agents.

A classification of the various ganglionic stimulants and blockers is presented, and their pharmacologic effects on the urinary bladder and urethra are discussed. Ganglionic stimulating drugs are of considerable interest in investigational work but are not presently used therapeutically. Ganglionic blockers include hexamethonium, tetraethylammonium, mecamylamine emepronium, pentolinium, chlorisondamine, and pemipidine. Of the numerous ganglionic blocking drugs that have appeared on the therapeutic scene, only mecamylamine, pentolinium, and trimethaphan are currently official.

Animals↗
PubMed1977

Uropharmacology: v. choline esters and other parasympathomimetic drugs.

Various parasympathomimetic drugs are discussed, including the choline esters, bethanechol, carbachol, methacholine chloride, and furtrethonium. Other cholinomimetic agents include muscarine, muscarone, arecholine, and pilocarpine. Anticholinesterase agents inhibit or inactivate acetylcholinesterase enzyme and thus result in a prolonged stimulation of cholinergic receptors by endogenous ACh. Bethanechol is the most widely used parasympathomimetic drug in the United States. Its action is mainly muscarinic with activity largely confined to the urinary bladder and to a lesser degree the gastrointestinal tract. It can be administered only subcutaneously or orally, and adequate dosage is necessary for a successful response.

Animals↗
PubMed1977

Uropharmacology: part VI. Parasympathetic depressants.

A discussion of the various parasympathetic depressants is presented. Belladonna alkaloids include atropine, the prototype, and scopolamine. Synthetic drugs include quaternary ammonium compounds with antimuscarinic activity such as methantheline, propantheline, and other drugs such as isopropamide, pipenzolate methylbromide, and diphemanil methylsulfate. A miscellaneous class of drugs such as hemicholinium, valethamate, and oxybutynin chloride also possesses parasympathetic depressant activity. The pharmacologic properties and clinical usage of these drugs are discussed.

Acetylcholine↗
PubMed1977

Lower urinary tract pharmacology. I. Anatomic considerations.

With this issue Dr. Bissada, Dr. Finkbeiner, and Dr. Welch introduce a series on uropharmacology, starting with the lower urinary tract. Since an understanding of the anatomy, neurophysiology, and basic pharmacology is necessary, Part I is a description of the functional anatomy of the lower urinary tract and the mechanisms of continence and voiding. Part II is a review of the differences between somatic and autonomic reflexes; the afferent and efferent innervation of lower urinary tract; the organization of pelvic ganglionic cells and the spinal and supraspinal control of lower urinary tract function. Subsequent articles will be on basic pharmacology of lower urinary tract and individual drug classes.

Female↗
PubMed1976

Transurethral resection of prostate via perineal urethrostomy. Prospective study.

A controlled, prospective clinical study was undertaken to determine the incidence and cause of urethral strictures after transurethral resection. Patients were assigned to 1 of 3 groups. Group A consisted of patients in whom it was considered preferable for various reasons to perform prostatic resection through perineal urethrostomy; therefore, these were excluded from randomization. All other patients were randomized using a sealed-envelope method into Group B who underwent resection via perineal urethrostomy and Group C who underwent resection via the entire urethra. Strictures occurred in 6 of 42 patients in Group C postoperatively while patients in Group B remained free of strictures. This difference was statistically significant (p less than 0.05). It was concluded that strictures which occur result from the use of the resectoscope through the entire urethra and not from the use of indwelling catheters, and that performing prostatic resection via perineal urethrostomy is valuable in preventing the occurrence of such strictures.

Follow-Up Studies↗
PubMed1976

Rapid formation of a staghorn calculus in the canine kidney. A surgical model.

A model for immediate production of staghorn calculi in dogs is described. A paste made of gray investment is injected into the renal pelvis and allowed to solidify for 30 min. Calculi thus formed have a striking similarity to naturally occurring staghorn calculi and can be utilized by urology teaching programs to initiate residents in the technique of anatrophic nephrolithotomy.

Animals↗
PubMed1975

Evaluation of Sacks solution for hypothermic preservation of kidneys.

The efficacy of Sacks solution for hypothermic preservation of dog kidneys was determined. Complete ischemia was produced in one kidney for thirty minutes by clamping the renal pedicle in situ, followed by excision and immediate washout with the cold preservation fluid. Kidneys were stored in Sacks solution at 2 degree C. for forty-eight hours, reimplanted in the donor, and the normal, contralateral kidney was removed. Complete reversal of renal impairment with long-term survival was observed in 2 of 9 animals. Of 7 animals with graft failure, 2 showed the beginning of a tendency to reverse a rising serum creatinine at the time of death or sacrifice. In the remaining 5, creatinine rose unrelentingly until death or sacrifice occurred. The observed 22 per cent survival rate was significantly (p less than 0.05) less than the 83 per cent survival reported by Sacks, Petritsch, and Kaufman. Evidence suggestive of intrarenal deposits of MgHPO4-3H2O was found in 2 of 4 dogs sacrificed for graft failure. This raises questions of the solution's safety as well as its efficacy. We are unable to confirm the success of the original investigators with this new preservation solution.

Animals↗