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Biomedical subjects

D L Larson

Publications and source records attributed to D L Larson.

At least 109 records · Page 6Linked to original sources
PubMed1982

Giant intracranial and extracranial meningioma: case report and review of the literature.

Large extracranial extensions of intracranial meningiomas are rare. We report the case of a 63-year-old man with a giant parietal occipital meningioma, which was removed successfully without significant complications. The tumor's total 2600-g mass makes it one of the largest of central nervous system origin ever resected. We detail the problem of dealing with such a tumor and review similar cases.

Cerebral Angiography↗
PubMed1981

The irreversible narcotic antagonistic and reversible agonistic properties of the fumaramate methyl ester derivative of naltrexone.

The fumaramate methyl ester derivatives of naltrexone (beta-FNA) and oxymorphone (beta-FOA) were both found to be reversible agonists on the guinea pig ileal longitudinal muscle preparation. In addition, beta-FNA possessed on irreversible antagonistic effect against morphine whereas beta-FOA had no such capacity. Analysis by pA2 values revealed that beta-FOA resembled pure agonists like morphine and enkephalin while beta-FNA resembled the mixed agonist-antagonists like nalorphine and pentazocine. The antagonism by beta-FNA was very selective in that it antagonized pure agonists but had little or no effect on the effects of either mixed agonist-antagonists, ethylketocyclazocine or other non-opiate-type agonists like norepinephrine.

Affinity Labels↗
PubMed1981

Allylprodine analogues as receptor probes. Evidence that phenolic and nonphenolic ligands interact with different subsites on identical opioid receptors.

The m-hydroxy analogues of allylprodine and related structures have been synthesized and tested for narcotic agonist and antagonist activity on the electrically stimulated guinea pig ileum and by the hot-plate procedure in mice. It has been found that m-hydroxyallylprodine (alpha-2) is neither an agonist nor antagonist. Other phenolic congeners similarly have little or no activity. The fact that these results are in dramatic contrast with the structure-activity profile of morphine and closely related opiates has led to the proposal that the interaction of morphine and allylprodine (alpha-1) with the mu opioid receptor differs. This difference is postulated to arise from the recognition of the aromatic groups of morphine and alpha-1 by different aromatic-binding subsites of the receptor. These subsites are suggested to be identical with those which recognize the aromatic rings of the Tyr1 and Phe4 of the enkephalins and endorphins. A receptor model consistent with these results is proposed.

Animals↗
PubMed1981

An objective method for early diagnosis of gram-negative septicemia in burned children.

The present investigation was undertaken to standardize the early diagnosis of Gram-negative septicemia in burned children. Data were collected by means of a matrix which encompassed eight clinical variables routinely monitored by nursing personnel. These variables were evaluated according to their severity using a numerical scale of 0 to 3. A sepsis score was thus calculated for each of 243 burned patients, three times a day throughout their entire hospitalization. Eighty patients with suspiciously high scores (controls) were subjected to a battery of ten laboratory tests aimed at confirming the presence or absence of septicemia. During the 26 months of the study 16 patients (22 episodes) had clinical and laboratory evidence of Gram-negative septicemia. Multiple regression and discriminant analysis techniques were then used to develop statistical models for early diagnosis of septicemia. The two most practical and reliable of these are reported herein. Model I and II would have predicted the diagnosis of sepsis, 83% and 86% of the time, respectively, 1 day before the diagnosis was made using conventional methods. The false positive rates of Models I and II were 7% and 3%, respectively. On the basis of this information it seems possible and rewarding to utilize decision-making charts for monitoring and diagnosis of septicemia.

Adolescent↗
PubMed1981

Prolatin secreting pituitary adenomas.

Prolactin secreting adenomas are the most frequently (50%) occurring pituitary adenoma. They occur more commonly in women than in men (4:1). Impairment of gonadal function accounts for the predominant symptoms in both sexes. Forty females and ten males with prolactin secreting adenomas were treated with selective adenoma removal by transsphenoidal surgery. Duration of symptoms varied from two months to 25 years. Twenty percent of the women and 100% of the men had invasive adenomas, a tumor that is difficult or impossible to eradicate. The chances of surgically correcting hyperprolactinemia in the female patient was 75% if the preoperative basal prolactin was 200 ng/ml or less, or 71% if the adenoma was non-invasive. The men were more difficult to treat because they all had invasive adenoma. In 50% of the men, prolactin was normalized by surgery. Early recognition of these patients before the adenomas become invasive is needed.

Adenoma↗
PubMed1980

The topical anti-inflammatory effects of piroxicam in rodents.

Piroxicam is a structurally novel, long-acting anti-inflammatory drug with potent activity following oral administration in animal models of inflammation and in human inflammatory diseases. The present studies, performed in rats, demostrate that topically applied piroxicam is a potent inhibitor of inflammation induced by either carrageenin or complete Freund's adjuvant. Comparable potencies (ED50 approximately 1--5 mg/kg) were obtained for topically and orally administered piroxicam in these models of inflammation. The potency of topical piroxicam exceeds that of topically applied bufexamac or phenylbutazone in the rat adjuvant arthritis model.

Administration, Oral↗
PubMed1980

Pharmacological studies with an alkylating narcotic agonist, chloroxymorphamine, and antagonist, chlornaltrexamine.

The 6-bis(2)chloroethyl)amino derivatives of oxymorphone and naltrexone, chloroxymorphamine (COA) and chlornaltrexamine (CNA), respectively, produce an irreversible inhibition of [3H]naltrexone binding to mouse brain homogenates. Intracerebroventricular (i.c.v.) injection of COA (4 nmol/mouse) elicits analgesia which lasts 4 times longer than analgesia produced by equimolar and equieffective dose of oxymorphone. The analgesia induced by COA can be reversed and blocked by naloxone. Injections of both COA and CNA i.c.v. antagonize morphine-induced analgesia for 3 days. Similarly, when [3H]naltrexone binding is measured in brains from mice pretreated i.c.v. with COA or CNA, there is a significant decrease in total specific binding for 3 days after pretreatment. These data suggest that CNA and COA alkylate the opioid receptors to produce antagonist and agonist-antagonist effects, respectively. The implications of these findings are discussed with respect to their effect on our perception of the opioid receptor-narcotic agonist interaction and the mechanisms of tolerance and dependence.

Analgesics↗
PubMed1980

Nasal obstruction as a complication of pharyngeal flap surgery.

In a series of 85 patients who had pharyngeal flap surgery at Indiana University Medical Center, We found an unusually high incidence of hyponasality with total or near total nasal obstruction. The nasal obstruction was often occult, detected only after careful questioning and examination. Nasal obstruction was associated with peri-operative infection or micrognathia as in the Pierre Robin Anomalad. Flap division or port revision yielded a significant relief of the nasal obstruction and achievement of normal nasal balance.

Adolescent↗
PubMed1979

Chloroxymorphamine, and opioid receptor site-directed alkylating agent having narcotic agonist activity.

Chloroxymorphamine, the 6beta-N,N-bis(2-chloroethyl) derivative of oxymorphone, is a potent nonequilibrium narcotic agonist in the longitudinal muscle preparation of guinea pig ileum. The corresponding naltrexone analog,chlornaltrexamine, is a potent nonequilibrium antagonist of morphine. These receptor sitedirected alkylating agents possess considerable potenial as pharmacologic and biochemical probes of apoid receptors.

Alkylating Agents↗