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M D Smith

Publications and source records attributed to M D Smith.

At least 127 records · Page 7Linked to original sources
PubMed2000

Evaluation of patient partners in the teaching of the musculoskeletal examination.

OBJECTIVE: To evaluate student preferences and examination outcomes of 2 different methods of teaching musculoskeletal (MSK) medicine examination techniques. METHODS: Year 2 students in a 4 year graduate medical school were randomized to 3 teaching groups: students in Group 1 were taught by rheumatology fellows, Group 2 by patient partners, while group 3 were randomly allocated to either patient partner (3A) or rheumatology trainee (3B) teaching. All students were debriefed at the end of each teaching block of 4 weeks for feedback on their teaching experience using a standardized questionnaire. In addition, at the end of the academic year, all students sat an objective structured clinical examination (OSCE) in clinical skills that contained a rheumatology station. The effect of method of teaching on students' performance in the rheumatology station was analyzed. RESULTS: Eighty medical students participated in the study. Overall, there was no difference in student ratings of either mode of teaching, although the students reported that patient partner teaching gave more opportunity to practice MSK examination skills and also provided greater feedback to the student. Students reported a preference for rheumatology trainee teaching because they believed the teaching would be more relevant to the content of the examination. There was no statistically significant difference in the performance of the students in the OSCE rheumatology station in regard to the mode of teaching they had received prior to the examination. CONCLUSION: Patient partner teaching is as effective a method of teaching clinical skills in MSK medicine as a traditional resident based form of teaching, with student benefits from patient feedback and greater "hands-on" opportunities. The assessment process should incorporate patient partners to assess the unique aspects of patient educator based teaching of MSK examination techniques.

Clinical Competence↗
PubMed2000

Intratracheal clenbuterol in the horse: its pharmacological efficacy and analytical detection.

Clenbuterol, a beta2 agonist/antagonist, is the only bronchodilator approved by the US Food and Drug Administration for use in horses. The Association of Racing Commissioners International classifies clenbuterol as a class 3 agent, and, as such, its identification in post-race samples may lead to sanctions. Anecdotal reports suggest that clenbuterol may have been administered by intratracheal (IT) injection to obtain beneficial effects and avoid post-race detection. The objectives of this study were (1) to measure the pharmacological efficacy of IT dose of clenbuterol and (2) to determine the analytical findings in urine in the presence and absence of furosemide. When administered intratracheally (90 microg/horse) to horses suffering from chronic obstructive pulmonary disease (COPD), clenbuterol had effects that were not significantly different from those of saline. In parallel experiments using a behavior chamber, no significant effects of IT clenbuterol on heart rate or spontaneous locomotor activity were observed. Clenbuterol concentrations in the urine were also measured after IT dose in the presence and absence of furosemide. Four horses were administered i.v. furosemide (5 mg/kg), and four horses were administered saline (5 mL). Two hours later, all horses were administrated clenbuterol (IT, 90 microg), and the furosemide-treated horses received a second dose of furosemide (2.5 mg/kg, i.v.). Three hours after clenbuterol dose (1 h after hypothetical 'post-time'), the mean specific gravity of urine samples from furosemide-treated horses was 1.024, well above the 1.010 concentration at which furosemide is considered to interfere with drug detection. There was no interference by furosemide with 'enhanced' ELISA screening of clenbuterol equivalents in extracted and concentrated samples. Similarly, furosemide had no effect on mass spectral identification or quantification of clenbuterol in these samples. These results suggest that the IT dose of clenbuterol (90 microg) is, in pharmacological terms, indistinguishable from the dose of saline, and that, using extracted samples, clenbuterol dose is readily detectable at 3 h after dosing. Furthermore, concomitant dose of furosemide does not interfere with detection or confirmation of clenbuterol.

Administration, Inhalation↗
PubMed2000

Sildenafil citrate (Viagra) is effective and well tolerated for treating erectile dysfunction of psychogenic or mixed aetiology.

Sildenafil citrate (Viagra) has been shown to be an effective treatment for erectile dysfunction (ED) of organic aetiology. This study assessed the efficacy and tolerability of sildenafil for treating ED of psychogenic and mixed psychogenic/organic aetiology. Men with ED of psychogenic and mixed aetiology were randomised in a double-blind, fixed-dose study to placebo (n = 95) or sildenafil 10 mg (n = 90), 25 mg (n = 85), or 50 mg (n = 81) once daily for 28 days. Efficacy was evaluated with two global efficacy questions, a patient log of erectile activity, a sexual function questionnaire and a partner questionnaire. Patients receiving sildenafil had significantly more grade 3 (hard enough for penetration) or grade 4 (fully hard) erections per week than patients receiving placebo, and a greater proportion of patients receiving sildenafil reported that treatment had improved their erections (p < 0.001). Results of the sexual function questionnaire demonstrated significant improvement for patients with ED receiving sildenafil compared with patients receiving placebo for frequency, hardness and duration of erections (p < 0.01), and for enjoyment of sexual intercourse and satisfaction with sex life (p < 0.05). The results of the partner questionnaire were consistent with the results reported by patients and showed that treatment with sildenafil was associated with significant improvement in the partners' own sex lives (p < 0.001). Adverse events were mostly mild to moderate in nature. The commonest adverse events were headache, dyspepsia, flushing, myalgia, arthralgia and flu syndrome. Discontinuations due to treatment-related adverse events were few, ranging from 1.1% to 6.2% for patients receiving different doses of sildenafil and 4.2% for patients receiving placebo. Sildenafil is an effective and well-tolerated treatment for ED of psychogenic or mixed aetiology with once-daily dosing.

Adolescent↗
PubMed1999

Regulation of NGFI-A (Egr-1) gene expression by the POU domain transcription factor Brn-3a.

NGFI-A is an immediate early gene (IEG) that is transcriptionally induced by nerve growth factor (NGF) in PC12 cells and has been implicated in a number of cellular responses. Studies have shown that elements within the first 106 base pairs of the NGFI-A promoter contribute to its induction by NGF in PC12 cells. One element, within the serum response element (SRE) bridge region, bears strong homology to a motif previously identified in promoters regulated by the Brn-3a POU domain transcription factor. We report here that Brn-3a activates the NGFI-A promoter in neurons (both primary and cell lines). Analysis revealed that this response requires sequences between positions -49 and -106. Whilst DNA-protein interaction studies failed to identify a site bound directly by Brn-3a, the data presented here suggest that Brn-3a may cooperate in the regulation of NGFI-A gene expression in neurons, possibly during the developmental switch between neurotrophin dependency that occurs during neurogenesis.

3T3 Cells↗
PubMed1999

p53 suppresses the activation of the Bcl-2 promoter by the Brn-3a POU family transcription factor.

The Brn-3a POU family transcription factor has been shown to strongly activate expression of the Bcl-2 proto-oncogene and thereby protect neuronal cells from programmed cell death (apoptosis). This activation of the Bcl-2 promoter by Brn-3a is strongly inhibited by the p53 anti-oncogene protein. This inhibitory effect of p53 on Brn-3a-mediated transactivation is observed with nonoverlapping gene fragments containing either the Bcl-2 p1 or p2 promoters but is not observed with other Brn-3a-activated promoters such as in the gene encoding alpha-internexin or with an isolated Brn-3a binding site from the Bcl-2 promoter linked to a heterologous promoter. In contrast, p53 mutants, which are incapable of binding to DNA, do not affect Brn-3a-mediated activation of the Bcl-2 p1 and p2 promoters. Moreover, Brn-3a and p53 have been shown to bind to adjacent sites in the p2 promoter and to directly interact with one another, both in vitro and in vivo, with this interaction being mediated by the POU domain of Brn-3a and the DNA binding domain of p53. The significance of these effects is discussed in terms of the antagonistic effects of Bcl-2 and p53 on the rate of apoptosis and the overexpression of Brn-3a in specific tumor cell types.

Cells, Cultured↗
PubMed1999

Sildenafil for treatment of erectile dysfunction in men with diabetes: a randomized controlled trial. Sildenafil Diabetes Study Group.

CONTEXT: Erectile dysfunction is common in men with diabetes. OBJECTIVE: To assess the efficacy and safety of oral sildenafil citrate in the treatment of erectile dysfunction in men with diabetes. DESIGN: A multicenter, randomized, double-blind, placebo-controlled, flexible dose-escalation study conducted May through November 1996. SETTING: Patients' homes and 19 clinical practice centers in the United States. PATIENTS: A total of 268 men (mean age, 57 years) with erectile dysfunction (mean duration, 5.6 years) and diabetes (mean duration, 12 years). INTERVENTIONS: Patients were randomized to receive sildenafil (n = 136) or placebo (n = 132) as needed, but not more than once daily, for 12 weeks. Patients took the study drug or placebo 1 hour before anticipated sexual activity. The starting dose of sildenafil citrate was 50 mg, with the option to adjust the dose to 100 mg or 25 mg based on efficacy and tolerability, to be taken as needed. MAIN OUTCOME MEASURES: Self-reported ability to achieve and maintain an erection for sexual intercourse according to the International Index of Erectile Function and adverse events. RESULTS: Two hundred fifty-two patients (94%) completed the study (131/136 in the sildenafil group, 121/132 in the placebo group). By intention-to-treat analysis, at 12 weeks, 74 (56%) of 131 patients in the sildenafil group reported improved erections compared with 13 (10%) of 127 patients in the placebo group (P<.001). The proportion of men with at least 1 successful attempt at sexual intercourse was 61 % (71/ 117) for the sildenafil group vs 22% (25/114) for the placebo group (P<.001). Adverse events related to treatment were reported for 22 (16%) of 136 patients taking sildenafil and 1 (1%) of 132 patients receiving placebo. The most common adverse events were headache (11% sildenafil, 2% placebo), dyspepsia (9% sildenafil, 0% placebo), and respiratory tract disorder (6% sildenafil, 2% placebo), predominantly sinus congestion or drainage. The incidence of cardiovascular adverse events was comparable for both groups (3% sildenafil, 5% placebo). CONCLUSION: Oral sildenafil is an effective and well-tolerated treatment for erectile dysfunction in men with diabetes.

Adult↗
PubMed1999

Acquired immunodeficiency syndrome-related intraocular B-cell lymphoma.

OBJECTIVES: To present the full clinical spectrum of the acquired immunodeficiency syndrome-related intraocular lymphoma as manifested in the eye, specifically retinal lymphoma associated with primary central nervous system lymphoma, isolated ocular lymphoma, and choroidal lymphoma associated with systemic lymphoma. METHODS: Three patients with acquired immunodeficiency syndrome were noted to have atypical retinal lesions. Diagnostic retinal biopsy in 2 patients and postmortem examination of the eyes in the third case were performed. RESULTS: Diagnostic retinal biopsy in the first 2 patients revealed retinal B-cell lymphoma. Initial systemic evaluation showed the eyes to be the sole site of disease. Later, in 1 of these patients, the lymphoma spread to the brain. The third patient developed an acute abdomen 4 months after the development of his ocular findings. The histological evaluation of the resected bowel revealed high-grade B-cell lymphoma. The patient died 1 week later and postmortem analysis of the eyes disclosed the presence of lymphoma in the choroid of both eyes. CONCLUSIONS: This is the most complete series of patients with acquired immunodeficiency syndrome-related intraocular B-cell lymphoma and, to our knowledge, provides the first 2 cases diagnosed by retinal biopsy. These 3 cases present the full clinical spectrum of the disease as manifested in the eye.

Adult↗
PubMed1999

Randomized trial of sildenafil for the treatment of erectile dysfunction in spinal cord injury. Sildenafil Study Group.

Erectile dysfunction is a common complication of spinal cord injury. This double-blind, placebo-controlled, two-way crossover study assessed the efficacy and safety of oral sildenafil in men with erectile dysfunction caused by traumatic spinal cord injury. A total of 178 men (mean age, 38 years) received placebo or sildenafil 1 hour before sexual activity for 6 weeks; after a 2-week washout period, the men received the alternate treatment for 6 weeks. The 50-mg starting dose could be adjusted to 100 or 25 mg based on efficacy and tolerability. Efficacy was assessed by using global efficacy questions, the International Index of Erectile Function (IIEF), and a patient log of erectile activity. Of 143 men with residual erectile function at baseline, 111 (78%) reported improved erections and preferred sildenafil to placebo. For all men (including those who reported no residual erectile function at baseline), 127 of 168 (76%) reported improved erections and preferred sildenafil to placebo. For all men, 132 of 166 (80%) reported that sildenafil improved sexual intercourse compared with 17 of 166 men (10%) reporting improvement with placebo. IIEF questions assessing the ability to achieve and maintain erections and satisfaction with sexual intercourse demonstrated significant improvement with sildenafil. Sildenafil was well tolerated, with a low rate of discontinuation because of treatment-related adverse events (2% vs 1% for placebo). Oral sildenafil is an effective and well-tolerated treatment for erectile dysfunction caused by spinal cord injury.

Administration, Oral↗
PubMed1999

Clinical utility of the flow cytometric technique for shared rheumatoid epitope.

The shared rheumatoid epitope (SRE) on the MHC class II antigen-presenting molecule constitutes a probable genetic risk factor for the occurrence of rheumatoid arthritis (RA) and may also determine disease severity. We have used a novel flow cytometric technique to determine the SRE in over 500 predominantly Caucasian patients attending a general rheumatology clinic. This technique has been validated against a polymerase chain reaction (PCR)/SSO molecular method. The SRE was observed in 90% of patients with Felty's syndrome (n = 10) and 75% of patients with RA (n = 178) as compared with 39% of patients with osteoarthritis or non-inflammatory rheumatic disorders (n = 73). Thus, the SRE determined by this method has a sensitivity for RA of 0.75, a specificity of 0.62 and an estimated positive predictive value of 0.02. In our RA cohort, there was no correlation between the functional outcome (health assessment questionnaire score) and SRE status. In conclusion, the determination of the SRE status by a flow cytometric method was found to have only modest sensitivity and specificity for RA; furthermore, the SRE did not correlate with functional outcomes. The clinical utility of the SRE assay is yet to be defined.

Arthritis, Rheumatoid↗
PubMed1999

Treatment of acute liver failure: hybrid liver support. A critical overview.

Hybrid liver support systems, which combine living cells of the liver in an extracorporeal circuit, have entered the first clinical trials in patients with acute liver failure. The goal of the different developments is to provide within a few hours a biological support of the patient's failing liver. Different technical solutions can be found to provide a sufficient functional mass of liver cells to the patient. Within this article, the biotechnical and clinical backgrounds of these developments are discussed, initial clinical results are summarized and an evaluation of this method as experimental treatment is given.

Animals↗
PubMed1999

Sildenafil citrate (Viagra) in erectile dysfunction: near normalization in men with broad-spectrum erectile dysfunction compared with age-matched healthy control subjects.

OBJECTIVES: To evaluate the efficacy, safety, and tolerability of sildenafil in men with broad-spectrum erectile dysfunction (ED), with reference to age-matched healthy control subjects. METHODS: One hundred eleven patients were enrolled in a randomized, double-blind, placebo-controlled, parallel-group, 12-week, flexible-dose study. Efficacy assessments included the International Index of Erectile Function (IIEF), a global assessment question, and patient event log data. In a separate, nontreatment study, 109 control subjects also completed the IIEF. RESULTS: Mean IIEF scores at baseline were significantly lower for patients with ED than for control subjects without a history of ED. After treatment, mean IIEF scores for patients receiving sildenafil approached values observed in control subjects and were significantly higher than mean scores for patients receiving placebo (P<0.01). Responses to the global assessment question and patient log data corroborated the IIEF results. Sildenafil was well tolerated, with no discontinuations because of adverse events. CONCLUSIONS: The results indicate that sildenafil, an effective oral therapy for the treatment of broad-spectrum ED, is associated with a near normalization of patient erectile function.

Adult↗
PubMed1999

Diagnostic evaluation of the erectile function domain of the International Index of Erectile Function.

OBJECTIVES: To evaluate the erectile function (EF) domain of the International Index of Erectile Function (IIEF) as a diagnostic tool to discriminate between men with and without erectile dysfunction (ED) and to develop a clinically meaningful gradient of severity for ED. METHODS: One thousand one hundred fifty-one men (1035 with and 116 without ED) who reported attempting sexual activity were evaluated using data from four clinical trials of sildenafil citrate (Viagra) and two control samples. The statistical program Classification and Regression Trees was used to determine optimal cutoff scores on the EF domain (range 6 to 30) to distinguish between men with and without ED and to determine levels of ED severity on the EF domain using the IIEF item on sexual intercourse satisfaction. RESULTS: For a 0.5 prevalence rate of ED, the optimal cutoff score was 25, with men scoring less than or equal to 25 classified as having ED and those scoring above 25 as not having ED (sensitivity 0.97, specificity 0.88). Sensitivity analyses revealed a robust statistical solution that was well supported with different assumed prevalence rates and several cross-validations. The severity of ED was classified into five categories: no ED (EF score 26 to 30), mild (EF score 22 to 25), mild to moderate (EF score 17 to 21), moderate (EF score 11 to 16), and severe (EF score 6 to 10). Substantial agreement was shown between these predicted and "true" classes (weighted kappa 0.80). CONCLUSIONS: The EF domain possesses favorable statistical properties as a diagnostic tool, not only in distinguishing between men with and without ED, but also in classifying levels of ED severity. Clinical validation with self-rated assessments of ED severity is warranted.

Erectile Dysfunction↗
PubMed1999

Development and evaluation of an abridged, 5-item version of the International Index of Erectile Function (IIEF-5) as a diagnostic tool for erectile dysfunction.

An abridged five-item version of the 15-item International Index of Erectile Function (IIEF) was developed (IIEF-5) to diagnose the presence and severity of erectile dysfunction (ED). The five items selected were based on ability to identify the presence or absence of ED and on adherence to the National Institute of Health's definition of ED. These items focused on erectile function and intercourse satisfaction. For 1152 men (1036 with ED, 116 controls) analyzed, a receiver operating characteristic curve indicated that the IIEF-5 is an excellent diagnostic test. Based on equal misclassification rates of ED and no ED, a cutoff score of 21 (range of scores, 5-25) discriminated best (sensitivity=0.98, specificity=0. 88). ED was classified into five severity levels, ranging from none (22-25) through severe (5-7). Substantial agreement existed between the predicted and 'true' ED classes (weighted kappa=0.82). These data suggest that the IIEF-5 possesses favorable properties for detecting the presence and severity of ED.

Coitus↗
PubMed1999

A two-part pilot study of sildenafil (VIAGRA) in men with erectile dysfunction caused by spinal cord injury.

STUDY DESIGN: This was a two-part pilot study in men with erectile dysfunction (ED) due to spinal cord injury (SCI: cord level range T6-L5). Part I was a randomised, double-blind, two-way cross-over study comparing a single dose of sildenafil 50 mg or placebo. Part II was a randomised, double-blind, parallel-group evaluation of sildenafil 50 mg or placebo, taken as required (not more than once daily) approximately 1 h prior to sexual activity, over a period of 28 days. OBJECTIVES: To assay the efficacy and safety of sildenafil 50 mg and placebo. SETTING: Clinic- and home-based assessments in the United Kingdom. METHODS: A total of 27 subjects who were able to achieve at least a grade 2 erection (hard, but not hard enough for penetration) in response to penile vibratory stimulation (PVS) were recruited. In Part I, the reflexogenic response of the penis to PVS was evaluated in the clinic while in Part II, the response to treatment was assessed in the home (global efficacy. questionniare, diary). RESULTS: In Part I, 17/26 (65%) subjects had erections of >60% rigidity at the penile base (median duration 3.5 min) after sildenafil compared with 2/26 (8%) (median duration 0 min) alter placebo (P=0.0003). In Part II, 9/12 (75%) subjects on sildenafil and 1/14 (7%) subjects on placebo reported that the treatment had improved their erections (P<0.005), and 8/12 (67%) and 2/13 (15%) men, respectively, indicated that they wished to continue treatment (P<0.02). An analysis of diary data showed no difference between the groups with respect to the mean number of erections hard enough for penetration (P = 0.08). The mean proportion of attempts at sexual intercourse that were successful was 30 and 15%, respectively (P=0.21). Similarly, responses to the end-of-treatment questionnaire indicated that there were no significant differences between the groups with respect to the frequency of erections hard enough for sexual intercourse (P=0.47) or that lasted as long as the subject would have liked (P=0.11). No subject discontinued sildenafil due to adverse events. CONCLUSION: Sildenafil is an effective, well-tolerated oral treatment for ED in SCI subjects.

Adult↗