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S Dolan

Publications and source records attributed to S Dolan.

49 records · Page 3Linked to original sources
PubMed1994

Performances of candidates with osteopathic compared with allopathic subspecialty training on the American Osteopathic Board of Internal Medicine subspecialty certifying examinations 1984 to 1992.

The American Osteopathic Board of Internal Medicine has been examining various factors that may affect candidate performance on subspecialty certifying examinations. To see whether taking subspecialty training in an osteopathic compared with an allopathic institution could predict better performance on the certifying examinations, the authors analyzed examination performance for all candidates from 1984 through 1992. There was no significant difference between the mean scores for the two groups for any of the nine subspecialty certifying examinations. When the results from all nine examinations were pooled, the mean first-time examination takers' score for candidates in allopathic subspecialty programs (n = 201) was 78.3 and for those in osteopathic subspecialty programs (n = 153), 77.4 (P > 0.2). On the basis of these results, we cannot conclude that osteopathic subspecialty training is a factor that predicts better performance on the subspecialty certifying examination.

Certification↗
PubMed1992

A non-occlusive model of arterial thrombus formation in the rat and its modification by inhibitors of platelet function, or thrombin activity.

A technically simple model of arterial thrombosis in the rat, induced by a crush injury to the dorsal aorta is described. The mechanical injury to the artery caused deep medial injury and the formation of a platelet-rich thrombus with associated fibrin formation which was assessed both radiometrically and morphometrically. No significant inclusion of erythrocytes was noted in the thrombus. Administration of the platelet inhibitors aspirin, BM 13505 (a thromboxane receptor antagonist) or CGS 12970 (a thromboxane synthase inhibitor) reduced the extent of platelet deposition on the injured vessel, but no decrease in fibrin(ogen) was observed. In contrast, infusion of prostacyclin resulted in reductions in both these components of the thrombus. In studies involving inhibition of thrombin activity, the direct thrombin inhibitor CGP 39393 (recombinant desulphatohirudin) inhibited both the platelet and fibrin(ogen) deposition. The indirect thrombin inhibitors were less effective; unfractionated heparin and low-molecular-weight heparin inhibited both platelet and fibrin(ogen) deposition but only at doses which rendered the blood uncoagulable, as evaluated by the activated partial thromboplastin time. Dermatan sulphate only inhibited platelet deposition. The results suggest that thrombin plays a key role in the initiation of thrombus formation in this experimental model. The agonist prostaglandins (PGG2, PGH2, and TXA2) would appear to have a supporting role in the platelet deposition onto the thrombotic surface but do not have a role to play with respect to fibrin(ogen) deposition.

Animals↗
PubMed1991

Behavioral tolerance to flurazepam.

Rats were trained to earn 180 food pellets in daily, fixed-interval 1-min sessions. When performance had stabilized, a Before group was given a weekly 16 mg/kg flurazepam injection IP for 3 weeks immediately before the sessions, while an After group received their weekly injections immediately after the sessions. Then, the After group received 3 such weekly injections before the sessions. Behavioral tolerance developed by the 2nd flurazepam injection for the Before group, but for the After group, the 3 postsession flurazepam injections resulted in subsequent tolerance to presession flurazepam injection for session lever presses, but not for the time taken to earn 180 pellets. Dispositional tolerance to the serum elimination rate of flurazepam did not develop over the course of 3 injections. Behavioral suppression still evident in the initial portion of sessions with the 2nd and 3rd presession injection coincided with the duration of rising and high levels of serum flurazepam.

Animals↗
PubMed1991

Can adolescent suicide attempters be distinguished from at-risk adolescents?

Psychiatric disorders, psychosocial dysfunction, family pathology, and environmental stressors are thought to be risk factors for adolescent suicide attempts. Variables from each of these categories were examined, by means of a structured interview and questionnaires, to determine whether a group of 21 adolescent suicide attempters could be differentiated from a group of 34 normal control subjects and a group of 15 at-risk adolescents (teenagers with known risk factors but without recent suicide attempt). The attempters differed significantly from control subjects on a large number of variables, particularly in the areas of substance abuse, depression, self-image, interpersonal relationships, communication patterns, family support, and problem behaviors. Only three items--the Beck Hopelessness Scale score, the SCL-90-R Positive Symptom Distress Index, and a history of suicidal ideation--differentiated the attempters from the at-risk adolescents. A discriminant analysis revealed that hopelessness and suicidal ideation were able to identify 93% of the suicide attempters.

Adolescent↗
PubMed1990

Development and reversal of endotoxemia and endotoxin-related death in obstructive jaundice.

Gut-derived endotoxemia has been implicated in postoperative complications in patients with jaundice. It is thought that absence of bile in the gut predisposes to portal absorption of endotoxin and endotoxemia is reversed by oral bile salt replacement or internal biliary drainage and return of bile to the gut, but not by external drainage. We believe that the importance of gastrointestinal bile flow has been overestimated and biliary obstruction and the integrity of hepatocyte and Kupffer cell function are more important in the development and reversal of endotoxemia. In experiment 1, serum endotoxin concentrations were measured in control rats (n = 10) after choledochovesical fistula (n = 15) and bile duct ligation (n = 15) and after relief of biliary obstruction by internal drainage (choledochoduodenostomy; n = 8) and sterile external drainage (choledochovesical fistula; n = 8), with a quantitative limulus assay. In experiment 2, mortality rates were measured in similar groups 48 hours after administration of oral endotoxin (5 mg/100 gm) and intravenous lead acetate (5 mg/100 gm). Bilirubin levels were elevated in bile duct ligation (192 +/- 13 mumols/L) compared with control animals and those with choledochovesical fistula, internal drainage, and external drainage (10.6 +/- 1.5 mumols/L). In experiment 1, significant portal endotoxemia and systemic endotoxemia occurred in bile duct ligation (portal, 130.4 +/- 12.9 pg/ml; systemic, 91.8 +/- 11.0 pg/ml) but not in choledochovesical fistula (portal, 49.3 +/- 17.1 pg/ml; systemic, 27.2 +/- 11.5 pg/ml). Relief of obstruction by both internal and external drainage reversed endotoxemia. In experiment 2, significant death occurred in bile duct ligation (13 of 15) but not in choledochovesical fistula (3 of 15), and relief of obstruction by both internal and external drainage prevented death. These results confirm that biliary obstruction is a more important factor than is gastrointestinal bile flow in the development and reversal of endotoxemia.

Animals↗
PubMed1988

Carcinogenicity of quinoline, 4- and 8-methylquinoline and benzoquinolines in newborn mice and rats.

The relative tumorigenic activity of quinoline, 4-methylquinoline, 8-methylquinoline, and all three isomeric benzoquinolines was evaluated in newborn CD-1 mice and Sprague-Dawley rats. In the newborn-mouse bioassay, 0.25, 0.5 and 1.0 mumol of each compound in dimethylsulphoxide was administered by ip injection on days 1, 8 and 15 of life, respectively. The bioassay was terminated when the mice were 1 yr old. The incidence of liver tumours observed for those male mice treated with either quinoline or 4-methylquinoline was greater than 78%. 8-Methylquinoline, naphthalene, benzo[f]quinoline, benzo[h]quinoline and phenanthridine did not exhibit significant tumorigenic activity in this bioassay. In contrast to these results, none of these compounds induced a significant incidence of liver tumours in female mice. Each of these aza-arenes was administered to newborn Sprague-Dawley rats by supra-scapular injections of 200 mumol/kg body weight in dimethylsulphoxide on the first day of life, 100 mumol weekly at wk 2-7, and 20 mumol at wk 8. This bioassay was terminated when the rats were 78 wk old. No significant difference in tumour incidence was observed between the pups that had been treated with these aza-arenes and the controls. These data indicate that quinoline and 4-methylquinoline are more potent tumorigens than any of the three isomers of benzoquinoline evaluated in this study. In contrast to the potent hepatocarcinogenic activity observed for both quinoline and 4-methylquinoline in newborn mice, no significant tumorigenic activity was observed with these aza-arenes in newborn rats.

Animals↗
PubMed1987

Simultaneous determination of flurazepam and five metabolites in serum by high-performance liquid chromatography and its application to pharmacokinetic studies in rats.

A reversed-phase high-performance liquid chromatographic method is described which allows the quantification of flurazepam and five of its metabolites with a single, isocratic determination. In addition, it has the advantage of possessing a low detection limit and high precision. A 2 mm I.D. column was used to minimize sample size (50 microliter), increase sensitivity and reduce solvent consumption. The method was used to demonstrate that N-1-desalkylflurazepam, the major metabolite, has a short half-life in the rat in contrast to its prolonged life in humans.

Animals↗
PubMed1986

Group A streptococcal pharyngitis and bacteremia associated with a Ludwig's angina-like syndrome.

Ludwig's Angina (LA) is an infection of the submandibular and sublingual spaces usually initiated by abscesses of the inferior molars due to mixed oral flora. Pharyngitis due to group A beta-hemolytic streptococci (GABHS) rarely results in bacteremia. A patient presented with the classical findings of LA, and had no odontogenic focus but had GABHS pharyngitis and bacteremia. Attempts to isolate other microbiological organisms from the submandibular and sublingual spaces were unsuccessful. The patient required emergent tracheostomy and was treated with penicillin G for 4 wk with complete resolution of his clinical illness. The case demonstrates a previously unreported association between GABHS pharyngitis and the development of LA.

Arthritis, Infectious↗
PubMedDate not supplied

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