Assessment of English proficiency in international medical graduates by physician examiners and standardized patients

CONTEXT: Since 1986, the Ontario Ministry of Health has provided a medical licensure preparation programme for international medical graduates. Because of the diversity in candidates' oral English proficiency, this competency has been viewed as a particularly important selection criterion. OBJECTIVES: To assess and compare the quality of ratings of oral English proficiency of international medical graduates provided by physician examiners and by standardized patients (SPs). PARTICIPANTS AND MATERIALS: The study samples consisted of 73 candidates for the Ontario International Medical Graduate (IMG) Program, and physician examiners and SPs in five 10-minute encounter objective structured clinical examination (OSCE) stations. Materials used were a seven-item speaking performance rating instrument prepared for the Ontario IMG Program. METHODS: Rating sheets were scanned and the results analysed using SPSS 9.0 for Windows. RESULTS: Correlations between the physician and SP ratings on the seven items ranged from 0.52 to 0.70. The SPs provided more lenient ratings. Mean alpha reliability for the physicians' ratings on the seven items was 0.59, and for the SPs' 0.64. There was poor agreement between the two sets of raters in identifying problematic candidates. CONCLUSIONS: Notwithstanding the sizable correlations between the ratings provided by the two rater groups, the results demonstrated that there was little agreement between the two groups in identifying the potentially problematic candidates. The physicians were less prone than the SPs to rate candidates as problematic. SPs may be better placed than the physician examiners to directly assess IMG candidates' oral English proficiency.     

p53 gene expression in relation to indoor exposure to unvented coal smoke in Xuan Wei, China

Lung cancer mortality rates in Xuan Wei County, which are among the highest in China, have previously been associated with exposure to indoor emissions from burning smoky coal. To determine if this association is stronger among lung cancer patients with abnormal expression of p53, we performed a population-based case-control study. Ninety-seven newly diagnosed lung cancer patients and 97 controls, individually matched by age, sex, and home fuel type, were enrolled. We used immunocytochemical methods to assess p53 protein accumulation in exfoliated tumor cells isolated from sputum samples. As expected, the amount of lifetime smoky coal use was associated with an overall increase in lung cancer risk. Compared with subjects who used less than 130 tons of smoky coal during their lifetime, the odds ratios (OR) for lung cancer were 1.48 (95% confidence interval [CI], 0.73 to 3.02) for subjects exposed to 130 to 240 tons, and 3.21 (95% CI, 1.23 to 9.03) for subjects who used more than 240 tons of smoky coal (P for trend 0.01). The effect was due almost exclusively to the pattern in women, almost all of whom were nonsmokers. Further, among highly exposed women, the association was substantially larger and achieved statistical significance only among patients with sputum samples that were positive for p53 overexpression (OR, 18.72; 95% CI, 1.77 to 383.38 vs OR, 4.80; 95% CI, 0.66 to 43.87 for p53-negative cases). This study suggests that exposure to the combustion products of smoky coal in Xuan Wei is more strongly associated with women who have lung cancer accompanied by p53 protein overexpression in exfoliated tumor cells.     

Amphetamine-type central nervous system stimulants release norepinephrine more potently than they release dopamine and serotonin

A large body of evidence supports the hypothesis that mesolimbic dopamine (DA) mediates, in animal models, the reinforcing effects of central nervous system stimulants such as cocaine and amphetamine. The role DA plays in mediating amphetamine-type subjective effects of stimulants in humans remains to be established. Both amphetamine and cocaine increase norepinephrine (NE) via stimulation of release and inhibition of reuptake, respectively. If increases in NE mediate amphetamine-type subjective effects of stimulants in humans, then one would predict that stimulant medications that produce amphetamine-type subjective effects in humans should share the ability to increase NE. To test this hypothesis, we determined, using in vitro methods, the neurochemical mechanism of action of amphetamine, 3,4-methylenedioxymethamphetamine (MDMA), (+)-methamphetamine, ephedrine, phentermine, and aminorex. As expected, their rank order of potency for DA release was similar to their rank order of potency in published self-administration studies. Interestingly, the results demonstrated that the most potent effect of these stimulants is to release NE. Importantly, the oral dose of these stimulants, which produce amphetamine-type subjective effects in humans, correlated with the their potency in releasing NE, not DA, and did not decrease plasma prolactin, an effect mediated by DA release. These results suggest that NE may contribute to the amphetamine-type subjective effects of stimulants in humans.     

Urinary benzene as a biomarker of exposure among occupationally exposed and unexposed subjects

Urinary benzene (UB) was investigated as a biomarker of exposure among benzene-exposed workers and unexposed subjects in Shanghai, China. Measurements were performed via headspace solid phase microextraction of 0.5 ml of urine specimens followed by gas chromatography-mass spectrometry. This assay is simple and more sensitive than other methods (detection limit 0.016 microg benzene/l urine). The median daily benzene exposure was 31 p.p.m. (range 1.65-329 p.p.m.). When subjects were divided into controls (n = 41), those exposed to < or =31 p.p.m. benzene (n = 22) and >31 p.p.m. benzene (n = 20), the median UB levels were 0.069, 4.95 and 46.1 microg/l, respectively (Spearman r = 0.879, P < 0.0001). A linear relationship was observed between the logarithm of UB and the logarithm of benzene exposure in exposed subjects according to the following equation: ln(UB, microg/l) = 0.196 + 0.709 ln (exposure, p.p.m.) (r = 0.717, P < 0.0001). Considering all subjects, linear relationships were also observed between the logarithm of UB and the corresponding logarithms of four urinary metabolites of benzene, namely t,t-muconic acid (r = 0.938, P < 0.0001), phenol (r = 0.826, P < 0.0001), catechol (r = 0.812, P < 0.0001) and hydroquinone (r = 0.898, P: < 0.0001). Ratios of individual metabolite levels to total metabolites versus UB provide evidence of competitive inhibition of CYP450 enzymes leading to increased production of phenol and catechol at the expense of hydroquinone and muconic acid. Among control subjects UB was readily detected with a mean level of 0.145 microg/l (range 0.027-2.06 microg/l), compared with 5.63 microg/l (range 0.837-26.38 microg/l) in workers exposed to benzene below 10 p.p.m. (P < 0.0001). This suggests that UB is a good biomarker for exposure to low levels of benzene.     

Neurochemical neutralization of amphetamine-type stimulants in rat brain by the indatraline analog (-)-HY038

Amphetamine-type stimulants are substrates for the proteins that serve as transporters for the biogenic amines dopamine (DA), serotonin (5HT), and norepinephrine (NE) and release these neurotransmitters from neurons located in the peripheral and central nervous system. Using indatraline as a lead compound, we sought to develop a long-acting depot medication that would neutralize the deleterious effects of amphetamine-type stimulants. Our first efforts produced (+/-)-HY038, and its two stereoisomers, which are hydroxy-substituted analog of indatraline. The K(i) values for [(3)H]DA reuptake inhibition by (-)-HY038 and (+)-HY038 were 3.2 +/- 0.1 and 32 +/- 1 nM. Similar results were obtained for [(3)H]5HT reuptake inhibition. (-)-HY038 and (+)-HY038 were slightly less potent at inhibiting [(3)H]NE reuptake (K(i) values of 20 +/- 2 and 159 +/- 12 nM). Low doses of (-)-HY038 blunted the ability of AMPH to release [(3)H]DA by shifting the AMPH dose-response curve to the right in a dose-dependent manner. (-)-HY038 also inhibited the ability of (+)-methamphetamine and (+/-)-3,4-methylenedioxymethamphetamine ((+/-)-MDMA) to release [(3)H]DA. Low doses of (-)-HY038 blunted the ability of these stimulants to release [(3)H]NE and [(3)H]5HT by shifting their dose-response curves to the right in a manner similar to that seen for inhibition of [(3)H]DA release. These data indicate that (-)-HY038 inhibits the ability of AMPH, (+)-methamphetamine and (+/-)-MDMA to release DA, NE, and 5HT and therefore might have the potential to neutralize the neurotoxic and cardiovascular side-effects of substrate-type stimulants.     

A heart failure self-management program for patients of all literacy levels: A randomized, controlled trial [ISRCTN11535170]

Background  

Self-management programs for patients with heart failure can reduce hospitalizations and mortality. However, no programs have analyzed their usefulness for patients with low literacy. We compared the efficacy of a heart failure self-management program designed for patients with low literacy versus usual care.     

Brain tumors and occupational exposures in a cohort of female textile workers in Shanghai, China

OBJECTIVES： This study assessed the associations between brain tumors and specific processes and exposures among female textile workers in Shanghai, China. METHODS： A case-cohort study was conducted that was nested in a cohort of textile workers originally included in a randomized trial of breast self-examination. Incident brain tumor cases （N=114） were identified from 1989 to 1998 from a tumor and death registry operated by the Shanghai Textile Industry Bureau. A subcohort （N=3188）, representing an agestratified random sample of the entire cohort, was selected as a comparison group.     

Protein adducts of 1,4-benzoquinone and benzene oxide among smokers and nonsmokers exposed to benzene in China.

Hemoglobin (Hb) and albumin (Alb) adducts of the benzene metabolites benzene oxide (BO) and 1,4-benzoquinone (1,4-BQ) were analyzed by gas chromatography-mass spectrometry in 43 exposed workers and 44 unexposed controls from Shanghai, China, as part of a larger cross-sectional study of benzene biomarkers. When subjects were divided into controls (n = 44) and workers exposed to 31 ppm (n = 22) of benzene, median 1,4-BQ-Alb adducts were 2110, 5850, and 13,800 pmol/g Alb, respectively (correlation with exposure: Spearman r = 0.762; P < 0.0001); median BO-Alb adducts were 106, 417, and 2400 pmol/g Alb, respectively (Spearman r = 0.877; P < 0.0001); and median BO-Hb adducts were 37.1, 50.5, and 136 pmol/g Hb, respectively (Spearman r = 0.757; P < 0.0001). To our knowledge, this is the first observation that adducts of 1,4-BQ are significantly correlated with benzene exposure. When compared on an individual basis, Alb adducts of 1,4-BQ and BO and Hb adducts of BO were highly correlated with each other and with urinary phenol and hydroquinone (P < 0.0001 for all of the comparisons). Although detectable in the assays, Hb adducts of 1,4-BQ and both Hb and Alb adducts of 1,2-BQ produced erratic results and are not reported. Interestingly, cigarette smoking increased Alb adducts of 1,4-BQ but not of BO, suggesting that benzene from cigarette smoke was not the primary contributor to the 1,4-BQ adducts.     

Genetic variation in insulin-like growth factors and brain tumor risk

Many studies support a role for insulin-like growth factors (IGFs) in the regulation of tumor cell biology. We hypothesized that single-nucleotide polymorphisms (SNPs) in IGF genes are risk factors for glioma and meningioma. To test the hypothesis, we examined associations of brain tumor risk with nine variants in five IGF genes in a hospital-based case-control study. The study was conducted at hospitals in Boston, Phoenix, and Pittsburgh between 1994 and 1998. Eligible cases were individuals (18 years or older) newly diagnosed with glioma or meningioma. Controls were selected among patients who were admitted to the same hospitals for a variety of nonmalignant conditions and frequency matched to cases by hospital, age, sex, race, and distance from residence. The present analysis was restricted to non-Hispanic whites. DNA was extracted from blood samples collected from 354 glioma cases, 133 meningioma cases, and 495 control individuals. We evaluated nine SNPs in five IGF genes (IGF1, IGF1R, IGF2, IGF2R, and IGFBP3). The majority of the analyzed IGF SNPs did not display statistically significant associations with glioma or meningioma. For glioma, one IGF1R SNP (rs2272037) indicated a possible association. No indications of association were seen for glioblastoma, but for low-grade gliomas, the odds ratio under a dominant model was 0.56 (95% confidence interval [CI], 0.35-0.90) for IGF1 rs6220, 2.98 (95% CI, 1.65-5.38) for IGF1R rs2272037, and 1.60 (95% CI, 0.90-2.83) for IGF1R rs2016347. Overall, our results do not provide strong evidence of associations of brain tumor risk with IGF polymorphic variants but identify several associations for glioma that warrant further examination in other, larger studies.     

Treatment of brain aneurysms

Up to 5% of the population may have an intracranial aneurysm, although many of these people are unaware of its presence. Most intracranial aneurysms remain asymptomatic, but a small proportion of them will rupture and bleed, causing life-threatening complications. Once diagnosed, treatment of aneurysms may include surgery or a minimally invasive endovascular coiling technique. As technologies improve and more aneurysms are deemed suitable for endovascular repair, there will be an increasing demand for radiologic technologists or radiologist assistants skilled in these complex diagnostic and therapeutic procedures.