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Many aspects of myogenesis are believed to be regulated by myoblast interactions with specific components of the extracellular matrix. For example, laminin has been found to promote adhesion, migration, and proliferation of mammalian myoblasts. Based on affinity chromatography, the alpha7beta1 integrin has been presumed to be the major receptor mediating myoblast interactions with laminin. We have prepared a monoclonal antibody, O26, that specifically reacts with both the X1 and the X2 extracellular splice variants of the alpha7 integrin chain. This antibody completely and selectively blocks adhesion and migration of rat L8E63 myoblasts on laminin-1, but not on fibronectin. In contrast, a polyclonal antibody to the fibronectin receptor, alpha5beta1 integrin, blocks myoblast adhesion on fibronectin, but not on laminin-1. The alpha7beta1 integrin also binds to a mixture of laminin-2 and laminin-4, the major laminin isoforms in developing and adult skeletal muscle, but O26 is a much less potent inhibitor of myoblast adhesion on the laminin-2/4 mixture than on laminin-1. Based on affinity chromatography, we suggest that this may be due to higher affinity binding of alpha7X1 to laminin-2/4 than to laminin-1.

Purpose: To assess the feasibility, reliability, and validity of an objective structured clinical examination (OSCE) for psychiatric clinical clerks., Method: In 1995 two parallel forms of a ten-station OSCE (eight clinical stations, two writing stations) were developed at the University of Toronto Faculty of Medicine Each 12-minute performance-based clinical station was assessed by a faculty psychiatrist using both a checklist for each student's performance content and a global-rating scale of the performance process. The students' clinical-station scores were calculated as the average of their content and process scores (expressed as percentages). Examiners also recorded an overall judgment of each students' performance (pass, borderline, or fail) and wrote [in collaboration with the standardized patient (SP) at that station] comments on each student's performance. There were two criteria for a passing grade: a total mark of 60% or higher across all ten stations and a "pass" or "borderline" mark in at least five of the eight clinical stations. Each OSCE form was administered three times., Results: The first form was used to examine 94 clerks, the second form to examine 98 clerks. The students' mean scores for the two forms were 70.47% (SD, 6.33%) and 67.66% (SD, 7.05%), respectively. In addition to the standard evaluation information collected on the students, several critical incidents occurred (e.g., a student's loss of control of emotions) that may identify potential problems in professional conduct. The direct cost for one administration of the examination was approximately Can$3,300: the largest portion of this was for the SPs' time spent in training and performing their roles., Conclusion: Preliminary evidence suggests that a psychiatry OSCE is feasible for assessing complex psychiatric skills. However, careful attention must be paid to SP training, examination monitoring, detection of critical incidents, and provision of feedback to students, faculty, and SPs. The university's previous system of oral examinations required approximately 600 faculty hours per year. The OSCE requires approximately 450 faculty hours, and the 150 hours saved almost cover the Can$20,000 that the examination costs each year. In all, the OSCE is an evaluation system that has demonstrable reliability and is more enjoyable for both the faculty and the students.

In most objective structured clinical examinations (OSCEs), communication skills are assessed as an 'add-on' to history-taking stations, rather than in stations designed to assess communication skills in the broadest sense. This study investigated the feasibility of developing such stations. In part one, 60 clinical clerks and 36 residents were rated in four 10-min emotionally charged situations portrayed by standardized patients. Inter-rater reliability was demonstrated (r = 0.59-0.63) and a highly significant effect of educational level was found. Generalizability between communication stations was low (0.17-0.20). Several explanations for poor generalizability, including poor discrimination as a result of low score variance and the confounding effect of content knowledge, were addressed in part 2. Ninety-five final-year medical students participated in an OSCE in which six 10-min encounters examined the students' ability to manage difficult emotional situations such as fear, anxiety, mania, sadness, confusion and anger. Half the students encountered a patient with moderate emotional symptoms and half an extreme emotional state. For difficult stations, students' scores were lower and standard deviation higher, suggesting that manipulating difficulty increases score variance and potentially discrimination. However, a strong interaction was found between difficulty and station content, and communication scores were highly correlated with content. Scenarios which created major communication difficulties (such as mania) resulted in much larger differences in scores between the easy and difficult versions. Communication OSCE stations can be created with acceptable reliability including difficult cases which address communication skills beyond simple history taking. Nevertheless, a generalizable set of communication skills remains elusive.

Objective: To examine the type and number of interactions of psychiatry residents, interns and clerks with sales representatives of pharmaceutical companies and the attitudes of physicians-in-training toward these interactions., Design: Survey conducted with the use of a self-report questionnaire., Setting: Seven teaching hospitals affiliated with the Department of Psychiatry, University of Toronto., Participants: All 105 residents, interns and clerks training in psychiatry at the seven teaching hospitals between October 1993 and February 1994 were eligible; 74 completed questionnaires, for a response rate of 70%. One respondent was excluded from the analysis., Outcome Measures: Number of personal meetings and "drug lunches" attended, number of drug samples and promotional items received and estimated value of gifts received by each physician-in-training during a 1-year period as well as attitudes of residents, interns and clerks about interactions with pharmaceutical representatives., Results: Median number of personal meetings reported was 1 (range 0 to 35), of drug lunches attended was 10 (range 0 to 70), of promotional items received was 2 (range 0 to 75) and of drug samples received was 1 (range 0 to 20). Trainees' median estimate of the value of gifts received was $20 (range $0 to $800 Fewer than one third felt that pharmaceutical representatives were a source of accurate information about drugs; however, 71% (52/73) disagreed with the statement that representatives should be banned from making presentations. Although only 15% (11/73) felt they had sufficient training about meeting with pharmaceutical representatives, 34% (25/73) felt that discussions with representatives would have no impact on their prescribing practices, and 56% (41/73) felt that receiving gifts would have no impact on prescribing. Fewer than half said they would maintain the same degree of contact with representatives if they did not receive promotional gifts. The more money and promotional items a physician-in-training had received, the more likely he or she was to believe that discussions with representatives did not affect prescribing (p < 0.05). Clerks, interns and junior (first-year and second-year) residents attended two to three times more drug lunches than senior (third-year and fourth-year) residents, and significantly more junior than senior residents felt that pharmaceutical representatives have a valuable teaching role. Junior residents were three times more likely than senior residents to have received drug samples., Conclusions: Interactions between pharmaceutical representatives and psychiatry residents, interns and clerks are common. The physicians-in-training perceive little educational value in these contacts and many, especially clerks, interns and junior residents, disavow the potential of these interactions to influence prescribing. Therefore, supervisors of postgraduate medical training programs may wish to provide instruction concerning potential conflicts of interest inherent in these types of interactions.

Thirty-six lung transplant candidates (n = 16), recipients (n = 11), and support people (n = 9) were examined for psychological distress, coping style, and orientation to independent learning before and after receiving a self-help book in a program designed to alleviate psychosocial distress and bolster adaptive coping. The subjects rated the book as highly acceptable, and none reported increased psychological distress. A further six subjects completed initial psychological measures but elected not to us the book. These subjects were compared with study completers and found to have significantly higher disengagement scores on the Coping Strategies Inventory. Although uncontrolled, significant changes were observed in coping strategies used by the completer group. The relevance of these findings to the use of bibliotherapy in medically ill populations is discussed.

Administration of the anesthetic gas N2O evoked an antinociceptive effect in two rodent antinociception paradigms. In the mouse abdominal constriction test, pretreatment with the nitric oxide synthase (NOS) inhibitor L-NG-nitroarginine (L-NOARG) caused dose-related antagonism of the antinociceptive effect of N2O but not of either morphine or trans(+/-)-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl)cyclohexyl] benzeneacetamide methane sulfonate. This antinociceptive effect was also antagonized by systemic pretreatment with the NOS inhibitors L-NG-nitroarginine methyl ester (L-NAME) and L-NG-monomethylnitroarginine. The antagonism of N2O by L-NOARG and L-NAME was completely reversed by i.c.v. administration of L-arginine but not D-arginine. In the absence of NOS inhibition, N2O antinociception was potentiated by i.c.v. treatment with L-arginine but not D-arginine. The i.c.v. pretreatment with L-NAME also reduced N2O antinociception; this antagonism was also stereospecifically reversed by L-arginine. In the rat hot plate test, the antinociceptive response to 70% N2O was antagonized in dose-related manner by i.c.v. pretreatment with L-NOARG or L-NAME. N2O antinociception was restored by i.c.v. treatment with L-arginine but not D-arginine. However, neither L-arginine nor D-arginine alone affected N2O antinociception. These results implicate a key role for NO in the mediation of the antinociceptive effects of N2O in both mice and rats.

The analgesic property of the anesthetic gas N2O has long been known and used to treat pain in clinical medicine and dentistry. The present study was conducted to identify by subtype and possible location the brain opioid receptors that mediate N2O antinociception in rats. A 5-min exposure to 70% N2O consistently evoked an antinociceptive effect in the hot plate test. This drug effect was partly antagonized in dose-related fashion by i.c.v. pretreatment with naltrexone, D-Phe-Cys-Tyr-D-Trp-Orn-Thr-Pen-Thr-NH2 and beta-endorphin, which block multiple, mu and epsilon opioid receptors, respectively. However, the N2O-evoked antinociception was unaffected by i.c.v. pretreatment with either the delta opioid antagonist naltrindole or the kappa opioid antagonist nor-binaltorphimine. When D-Phe-Cys-Tyr-D-Trp-Orn-Thr-Pen-Thr-NH2 was administered intracerebrally directly into the periaqueductal gray, N2O antinociception was partly antagonized in a dose-dependent manner. The antinociceptive response to N2O was uninfluenced by beta-endorphin administered into the periaqueductal gray. The findings of these pharmacological antagonism studies are consistent with the hypothesis that exposure to N2O causes a neuronal release of beta-endorphin. These results indicate that supraspinal mu and epsilon opioid receptors mediate N2O antinociception in the rat hot plate paradigm and that one central site of such mu but not epsilon opioid receptors is the periaqueductal gray.

The seroprevalence of antibodies to HIV-1, HTLV-I, and HCV was evaluated in three populations from northern rural Haiti: 1,727 patients attending the hospital for symptoms suggestive of HIV disease, 228 consecutive surgical patients, and 500 pregnant women were tested. HIV-1 seroprevalence was 6.1 and 4.0% in the last two groups, respectively, and 39.3% in the symptomatic population. Associated symptoms of wasting, cough, and diarrhea and a clinical diagnosis of AIDS were significantly predictive of HIV-1 seropositivity. Antibody to HTLV-I seroprevalence ranged from 2.2-5.3% in pregnant women, surgical patients, and HIV-seronegative symptomatic patients and was similar among the three groups when stratified by age. In contrast, HIV-1 seropositivity and HTLV-I seropositivity were significantly associated. The prevalence of confirmed antibody to HCV was low and not associated with either HIV-1 or HTLV-I seropositivity.

This secondary analysis from the National Adolescent Student Health Survey (NASHS) examined relationships between adolescents' personal and perceived peer attitudes toward condom use with gender and self-reported ethnic background. Descriptive results revealed general personal support and perceived peer support for condom use. Results from multivariate analysis of variance (MANOVAs) demonstrated significant interaction effects for the eighth grade sample [F = (4, 2383228) = 3530.01 p = .000], and the 10th grade sample [F = (4, 2636878) = 2594.41073, p = .000]. Contrasts revealed significant differences among all ethnic groups for both belief variables for the entire sample, eighth grade students, and 10th grade students. Though general support exists for condom use among U.S. eighth and 10th grade students, conviction varies among groups perhaps indicating a need for tailored messages about condom use, especially for Hispanic students. Implications for health education include the need for cultural-sensitive and gender-sensitive STD education.

The penetration of ceftazidime, a new broad-spectrum cephalosporin, into fluids from subcutaneous threads, suction blisters, and cantharidin blisters was studied in eight healthy male volunteers. A pharmacokinetic analysis showed fundamental differences between the models. The results obtained with the subcutaneous thread technique were similar to those of the peripheral compartment and were characteristic of a rapidly equilibrating compartment. The results obtained with the suction and cantharidin blister techniques were characteristic of slowly equilibrating compartments. We concluded that although one model will not accurately predict the penetration of an antibiotic in all clinical situations, each model will have its own particular application.

A conventional method of bacteriological examination of removed cerebrospinal fluid shunts was compared with another method which relies on microscopic and cultural examination of intraluminal fluid. Fifty-five shunts were tested. All eight cases of clinical shunt infection gave positive results with the latter method, whereas a further 23 shunts yielded positive cultures by the conventional method in the absence of clinical infection. The consequences of missed infections due to omission of microscopic examination and overdiagnosis using the conventional culture method are discussed.