Effect of tobacco smoke on hydrogen sulfide-induced rat thoracic aorta relaxation

Levels of hydrogen sulfide (H₂S), a gaseous signaling molecule, are reduced in the serum of individuals who smoke. We hypothesized that tobacco smoke influenced smooth muscle relaxation by decreasing H₂S levels and this effect could also influence expression of cystathionine γ-lyase (CSE) and sulfonylurea receptor-2 (SUR-2). The aim of this study was to explore the effect of tobacco smoke on H₂S-mediated rat thoracic aorta relaxation and its possible mechanism. Thirty-two Sprague-Dawley rats were divided into four groups: control (C) group, short-term smoker (SS) group, mid-term smoker (MS) group, and long-term smoker (LS) group. H₂S concentrations in serum, action of H₂S on rat aortic vascular relaxation, and expression of CSE and SUR-2 in thoracic aortic smooth muscle were measured. Although there was no significant difference in H₂S between the C and the SS groups, concentration of H₂S was significantly reduced in both the LS and MS groups compared to control (P<0.01). Furthermore, H₂S was significantly lower in the LS than in the MS group (P<0.05). Rat aortic vascular relaxation was lower in all three treatment groups compared to the control, with the most significant decrease observed in the LS group (P<0.05 compared to the MS group). Expression of CSE and SUR-2 was reduced in the LS and MS groups compared to control (P<0.05), with the lowest levels observed in the LS group (P<0.05). Therefore, tobacco smoke reduced expression of CSE and SUR-2 in rat thoracic aorta, which may inhibit H₂S production and vascular dilation.

Adherence to guidelines in monitoring amiodarone-induced thyroid dysfunction

RATIONALE, AIMS AND OBJECTIVES

Baseline thyroid function testing and regular follow-up of thyroid function under amiodarone usage was recommended by guidelines. Little is known about the status of amiodarone monitoring in real-world clinical care in Taiwan. The objective was to determine the rate of thyroid monitoring and to assess the clinical and physicians' characteristics associated with adequate monitoring in a tertiary referral centre for arrhythmia.

METHODS

We reviewed the medical records of patients receiving amiodarone during the period 2008-2009 at Taipei Veterans General Hospital. The rate of baseline and follow-up thyroid function monitoring during amiodarone therapy were calculated. Factors associated with guideline adherence to monitoring were analysed.

RESULTS

Among the 1319 enrolled cases, 36.4% (n = 480) underwent baseline thyroid function testing and 1.1% (n = 15) received measurement of anti-thyroid peroxidase antibody before amiodarone initiation. Regular follow up of thyroid function under amiodarone usage occurred in only 8.6% (n = 114) of cases. Baseline thyroid function was more likely to be present in patients of younger age (P < 0.001), female sex (P = 0.01), and in those who received amiodarone therapy from cardiologists (P < 0.001) or electrophysiologists (P < 0.001) with fewer years of service (P < 0.001). Upon multivariate analysis, only physicians' expertise (cardiologist versus non-cardiologist, OR = 5.67, 95% CI: 2.44-13.16) and years of service (OR = 0.97, 95% CI: 0.95-0.998) were significantly associated with adequate thyroid monitoring.

CONCLUSIONS

The rate of thyroid monitoring with amiodarone therapy had been suboptimal. Strategies to enhance guideline adherence are needed.

Voluntary attendance of small-group brainstorming tutoring courses intensify new clerk's "excellence in clinical care": a pilot study

BACKGROUND

Clerkship provides a unique way of transferring the knowledge and skills gathered during medical school's curriculum into real-ward clinical care environment. The annual program evaluation has indicated that the training of clerks in diagnostic and clinical reasoning skills needed to be enhanced. Recently, "clinical excellence" program have been promoted in our institution to augment the excellence in clinical care of new clerks. Current study aims to evaluate whether this pilot program improve the "clinical excellence" of new clerks.

METHODS

In a pilot study, groups of new clerks in years 2013 and 2014 voluntarily attended either a small-group brainstorming course or a didactic classroom tutoring courses as part of their 3-month internal medicine clinical rotation block. A third group of new clerks did not join either of the above courses and this group served as the control group. Pre-block/post-block self-assessment and post-block 5-station mini-Objective Subjective Clinical Examinations (OSCEs) were used to evaluate the effectiveness of these two additional courses that trained diagnostic and clinical reasoning skills.

RESULTS

Overtime, the percentages of new clerks that attended voluntarily either the small-group brainstorming or classroom tutoring courses were increased. Higher post-block self-assessed diagnostic and clinical reasoning skill scores were found among individuals who attended the small-group brainstorming courses compared to either the didactic group or the control group. In a corresponding manner, the small-group brainstorming group obtained higher summary OSCE_diag and OSCE_reason scores than either the didactic group or control group. For all basic images/laboratory OSCE stations, the individual diagnostic skill (OSCE_diag) scores of the small-group brainstorming group were higher than those of the didactic group. By way of contrast, only the clinical reasoning skill (OSCE_reason) scores of the basic electrocardiogram and complete blood count + biochemistry OSCE station of thesmall-group brainstorming group were higher than those of the didactic group. Among the small-group brainstorming group, clerks with higher cumulative learning hours (>30-h) had significant higher OSCE_diag and OSCE_reason scores (>400) than those with less cumulative learning hours.

CONCLUSION

Our pilot study provides a successful example of the use of a small-group tutoring courses for augmenting the diagnostic and clinical reasoning skills of new clerks. The positive results obtained during the initial 2-year long pilot "clinical excellence" program have encouraged the formal implementation of this course as part of the clerkship curriculum.

Using multimedia tools and high-fidelity simulations to improve medical students' resuscitation performance: an observational study

OBJECTIVES

The goal of our study was to shed light on educational methods to strengthen medical students' cardiopulmonary resuscitation (CPR) leadership and team skills in order to optimise CPR understanding and success using didactic videos and high-fidelity simulations.

DESIGN

An observational study.

SETTING

A tertiary medical centre in Northern Taiwan.

PARTICIPANTS

A total of 104 5-7th year medical students, including 72 men and 32 women.

INTERVENTIONS

We provided the medical students with a 2-hour training session on advanced CPR. During each class, we divided the students into 1-2 groups; each group consisted of 4-6 team members. Medical student teams were trained by using either method A or B. Method A started with an instructional CPR video followed by a first CPR simulation. Method B started with a first CPR simulation followed by an instructional CPR video. All students then participated in a second CPR simulation.

OUTCOME MEASURES

Student teams were assessed with checklist rating scores in leadership, teamwork and team member skills, global rating scores by an attending physician and video-recording evaluation by 2 independent individuals.

RESULTS

The 104 medical students were divided into 22 teams. We trained 11 teams using method A and 11 using method B. Total second CPR simulation scores were significantly higher than first CPR simulation scores in leadership (p<0.001), teamwork (p<0.001) and team member skills (p<0.001). For methods A and B students' first CPR simulation scores were similar, but method A students' second CPR simulation scores were significantly higher than those of method B in leadership skills (p=0.034), specifically in the support subcategory (p=0.049).

CONCLUSIONS

Although both teaching strategies improved leadership, teamwork and team member performance, video exposure followed by CPR simulation further increased students' leadership skills compared with CPR simulation followed by video exposure.

Circulating Fibroblast Growth Factor 21 is Associated with Diastolic Dysfunction in Heart Failure Patients with Preserved Ejection Fraction

Fibroblast growth factor 21 (FGF21), a polypeptide ligand promoted glucose homeostasis and lipids metabolism, was recently reported to attenuate cardiac hypertrophy. The aim of this study was to investigate the impact of FGF21 in diastolic heart failure. Subjects admitted for coronary angiogram were screened for heart failure, and those with left ventricular (LV) ejection fraction < 45% were excluded. Diastolic dysfunction was defined as functional abnormalities that exist during LV relaxation and filling by echocardiographic criteria. Plasma levels of FGF21 and N-terminal Pro-Brain Natriuretic Peptide (NT-pro-BNP) were determined. All patients were followed up for 1 year, or till the occurrence of heart failure readmission or death. Totally 95 patients with diastolic dysfunction and 143 controls were enrolled. Circulating FGF21 level was correlated with echocardiographic parameters of diastolic function and LV end-diastolic pressure (LVEDP). In multivariate logistic analysis, FGF21 was significantly associated with diastolic dysfunction, either identified by echocardiographic criteria (odds ratio: 2.97, p = 0.012) or confirmed with LVEDP level (odds ratio: 3.73, p = 0.030). Both plasma FGF21 (log rank p < 0.0001) and NT-pro-BNP levels (log rank p = 0.0057) showed good predictive power to the 1-year adverse cardiac events. This finding suggested FGF21 could be involved in the pathophysiology of diastolic heart failure.

Prediction of vascular dementia and Alzheimer's disease in patients with atrial fibrillation or atrial flutter using CHADS2 score

BACKGROUND

Atrial fibrillation (AF) is associated with an increased risk of dementia. However, limited data are available on the predictors of dementia in patients with AF. This study aimed to evaluate whether the CHADS2 score could be a useful tool for risk stratification with regard to dementia occurrence among patients with AF.

METHODS

AF patients were identified from the National Health Insurance sampling database, which has accumulated a total of 1,000,000 participants since 2000. After excluding patients diagnosed with dementia prior to the index day of enrollment, CHADS2 score was measured to investigate its association with the occurrence of dementia, including vascular dementia and Alzheimer's disease.

RESULTS

During the mean follow-up period of 3.71 ± 2.78 years, 1135 dementia cases (7.36%) were identified, including 241 cases of vascular dementia and 894 cases of Alzheimer's disease. In multivariate analysis, an increase of 1 point in the CHADS2 score was independently associated with a 54% increase in the risk of vascular dementia (hazard ratio = 1.54; 95% confidence interval, 1.41-1.69; p < 0.001) and a 40% increase in Alzheimer's disease (hazard ratio = 1.40; 95% confidence interval, 1.34-1.46; p < 0.001).

CONCLUSION

CHADS2 score is a useful predictor for the development of vascular dementia as well as Alzheimer's disease in patients with AF.

Sleep apnea and risk of aortic dissection: A nonrandomized, pair-matched cohort study

BACKGROUND

Sleep apnea (SA) was associated with increased prevalence of aortic dissection (AD) in studies that were criticized for either their small sample size or lack of prospective observation. Using a considerably larger nationwide, population-based database and a long-term prospective cohort design, our study strived to explore the relationship between SA and the subsequent development of AD.

METHODS

From 2000 to 2007, we gathered a study cohort consisting of 15,848 newly diagnosed cases of SA from Taiwan's National Health Insurance Research Database. For the control group, another 39,826 individuals without SA were matched for age, sex, and comorbidity. The two cohorts were followed-up to observe the occurrence of AD.

RESULTS

During an average 3.59 ± 2.41 years of follow-up, we observed 33 cases of new AD occurrence [non-SA (22, 0.1%) vs. SA (11, 0.1%), p=0.669], and the incidence of AD was similar for both groups. After adjusting for age, sex, and comorbidity, only age [hazard ratio (HR) 1.03; 95% confidence interval (CI), 1.01-1.06; p=0.006], male gender (HR 2.49; 95% CI, 1.07-5.79; p=0.034), and hypertension (HR 6.28; 95% CI, 2.36-16.67; p<0.001) were independently associated with AD diagnosis.

CONCLUSION

SA was not associated with an increased risk of AD using a large nationwide cohort database. Nonetheless, larger prospective studies or meta-analyses are recommended to confirm our findings.

Association of Serum Bilirubin with SYNTAX Score and Future Cardiovascular Events in Patients Undergoing Coronary Intervention

BACKGROUND

Bilirubin has emerged as an important endogenous antioxidant molecule, and increasing evidence shows that bilirubin may protect against atherosclerosis. The SYNTAX score has been developed to assess the severity and complexity of coronary artery disease. The aim of this study was to evaluate whether serum bilirubin levels are associated with SYNTAX scores and whether they could be used to predict future cardiovascular events in patients undergoing coronary intervention.

METHODS

Serum bilirubin levels and other blood parameters in patients with at least 12-h fasting states were determined. The primary endpoint was any composite cardiovascular event within 1 year, including death, nonfatal myocardial infarction, and target-vessel revascularization.

RESULTS

In total, 250 consecutive patients with stable coronary artery disease (mean age 70 ± 13) who had received coronary intervention were enrolled. All study subjects were divided into two groups: group 1 was defined as high SYNTAX score (> 22), and group 2 was defined as low SYNTAX score (≤ 22). Total bilirubin levels were significantly lower in the high SYNTAX score group than in the low SYNTAX score group (0.51 ± 0.22 vs. 0.72 ± 0.29 mg/dl, p < 0.001). By multivariate analysis, serum total bilirubin levels were identified as an independent predictor for high SYNTAX score (adjusted odds ratio: 0.28, 95% confidence interval 0.04-0.42; p = 0.004). Use of the Kaplan-Meier analysis demonstrated a significant difference in 1-year cardiovascular events between high (> 0.8 mg/dl), medium (> 0.5, ≤ 0.8 mg/dl), and low (≤ 0.5 mg/dl) bilirubin levels (log-rank test p = 0.011).

CONCLUSIONS

Serum bilirubin level is associated with SYNTAX score and predicts future cardiovascular events in patients undergoing coronary intervention.

Association between previous history of gout attack and risk of deep vein thrombosis - a nationwide population-based cohort study

Although the association of hyperuricemia and cardiovascular diseases is well established by previous research studies, the relationship between gout and deep vein thrombosis (DVT) remains unclear. We conducted a nationwide longitudinal cohort study to investigate the relationship between gout and DVT. We used the Taiwan National Health Insurance Research Database to identify patients with gout diagnosed in Taiwan during 2000–2011, and we followed up these patients to determine the incidence of DVT among them. The association between gout and DVT was analyzed by cox proportional hazard model. The study cohort included 35,959 patients with history of gout attack and 35,959 matched controls without gout attack. During the median follow-up of 7.5 ± 3.6 years, the incidence rate of DVT was significantly higher in patients with gout than that in control group (13.48 versus 9.77 per 10⁴ person-years, p < 0.001). Kaplan-Meier analysis revealed a tendency toward DVT development in gout patients (log rank test, p < 0.001). In a Cox model, patients with gout were found to have a 1.38-fold (95% confidence interval [CI], 1.18 to 1.62, p < 0.001) higher risk of developing DVT. Hyperuricemia with gout attack could be a possible risk predictor for DVT, but these findings need to be confirmed in future clinical and experimental studies.

Increased Circulating Visfatin Is Associated With Progression of Kidney Disease in Non-Diabetic Hypertensive Patients

BACKGROUD

Declining renal function is an independent risk factor for all-cause mortality in cardiovascular disease. Visfatin has been described as a marker of inflammation and endothelial dysfunction, but whether circulating visfatin levels are predictive to a subsequent decline in renal function remains unclear.

METHODS

In total, 200 nondiabetic, non-proteinuric hypertensive outpatients with initial serum creatinine (Scr) ≤1.5 mg/dl were enrolled. Plasma visfatin concentration and endothelial function estimated by brachial artery flow-mediated dilatation (FMD) were determined in the study subjects. The primary endpoints were the occurrence of renal events including doubling of Scr, 25% loss of glomerular filtration rate (GFR) from baseline values, and the occurrence of end-stage renal disease during follow-up.

RESULTS

The mean annual rate of GFR decline (ΔGFR/y) was -1.26±2.76 ml/min/1.73 m(2) per year during follow-up (8.6±2.5 years). At baseline, plasma visfatin was negatively correlated with estimated GFR. In longitudinal analysis, the ΔGFR/y was correlated with visfatin, baseline GFR, FMD, systolic blood pressure, and fasting blood glucose (FBG). Multivariate analysis indicated that increased visfatin (r = -0.331, P <0.001), baseline GFR (r = -0.234, P = 0.001), FMD (r = 0.163, P = 0.015), and FBG (r = -0.160, P = 0.015) are independent predictors of ΔeGFR/y. Cox regression model analysis showed that visfatin (hazard ratio (HR), 1.09; 95% confidence interval (CI), 1.05-1.13, P <0.001), FBG (HR, 1.01; 95% CI, 1.00-1.02, P = 0.020), and FMD (HR, 0.87; 95% CI, 0.76-1.00, P = 0.049) were independently associated with the risk of developing future renal events.

CONCLUSIONS

Increased circulating visfatin are associated with subsequent decline in renal function in nondiabetic hypertensive patients.

Hypertension subtypes modify metabolic response to thiazide diuretics

BACKGROUND

Blood pressure (BP) and metabolic response to thiazide diuretics might be varied in patients with different hypertension subtypes and ethnicities. This study aimed to investigate the response of BP and metabolic profiles to short-term thiazide treatment in an Asian cohort with different hypertension subtypes.

DESIGN

Serial ethnic Chinese nondiabetic subjects with hypertension were evaluated. After diet instruction and lifestyle modification for 2 weeks, patients who still had elevated systolic BP (SBP≥140 mmHg) and/or diastolic BP (DBP≥90 mmHg) were given 50 mg of hydrochlorothiazide daily for 2 weeks. The responses of BP and metabolic profiles were evaluated before and after treatment according to the patient's baseline BP subtype - isolated systolic hypertension (ISH), systo-diastolic hypertension (SDH) and isolated diastolic hypertension (IDH).

RESULTS

Hydrochlorothiazide treatment significantly reduced the BP in all 92 patients (62 males, aged 45·7 ± 9·6 years), irrespective of their baseline BP subtypes. In patients with SDH (n = 39) or IDH (n = 40), hydrochlorothiazide treatment significantly increased serum adiponectin (P = 0·001 and 0·007, respectively) and reduced asymmetric dimethylarginine levels (P < 0·001, in both groups). Serum cholesterol (P = 0·027) and fasting blood sugar levels (P = 0·044) were significantly improved only in the IDH patients. Furthermore, IDH was independently associated with changes in fasting blood sugar (β = -11·178, P = 0·022) and cholesterol (β = -22·654, P = 0·027).

CONCLUSIONS

The characteristics of the Asian hypertensive patients with diastolic hypertension can present a favourable metabolic response to the short-term hydrochlorothiazide treatment. The potential positive effect on cardiovascular risk should be validated in long-term studies in this diastolic type of hypertension.

The influence of gender on the communication skills assessment of medical students

BACKGROUND

Opinions on the interaction between the genders of standardized patients and examinees are controversial. Our study sought to determine the influence of gender on communication skills assessment in Eastern country.

METHODS

We recruited year 5 medical students from a medical college in Taiwan. They were assigned to obtain informed consent from either male or female age-matched standardized patients. Their performance was rated by standardized checklist rating scores and global rating scores. Either male or female examiners rated their performance.

RESULTS

A total of 253 medical students (166 male students and 87 female students) were recruited. The checklist rating scores for students interacting with male standardized patients were significantly lower than the scores for interactions with female standardized patients (male examiners, P=0.006; female examiners, P=0.001). For male students, the checklist rating scores were significantly lower for male standardized patients than for female standardized patients (male examiners, P=0.006; female examiners, P=0.008). For male standardized patients, male students had significantly lower checklist rating scores than female students when rated by male examiners (P=0.044). The global rating scores were similar except when female students interacted with male and female SPs and when rated by female examiners (P=0.004).

CONCLUSION

The gender of standardized patients influences communication skills assessment. In terms of checklist rating scores, female standardized patients seem preferable to minimize potential gender effects. In the best interest of students, global rating score may be preferable to checklist rating score, especially for male examinees.

Stevens-Johnson syndrome and toxic epidermal necrolysis in patients with malignancies

BACKGROUND

Malignancy is known to be associated with an increased mortality rate in patients with Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). However, risk factors contributing to the poor prognosis of patients with SJS/TEN with malignancies remain undefined.

OBJECTIVES

To explore the potential involvement of malignancy and its related factors contributing to the poor outcome of SJS/TEN, in a retrospective study.

METHODS

In total 517 patients with SJS/TEN were enrolled. Forty-seven who sustained various types of malignancies were analysed for numerous malignancy-related factors, including cancer types, clinical stages and chemotherapies given or not before the onset of SJS/TEN.

RESULTS

We found that the mortality rate of patients with SJS/TEN with malignancies was higher than that of patients without malignancies (32%, 15/47 vs. 8·5%, 40/470, respectively) (P < 0·001). The use of phenytoin was significantly higher in the malignancy group. The presence of hepatocellular carcinoma (80%, four of five; P < 0·001; odds ratio 43) and colorectal cancer (67%, two of three; P = 0·022; odds ratio 21·5) significantly increased the death rate of patients with SJS/TEN, whereas lung cancer and urothelial carcinoma did not. Patients who had received ongoing or recent chemotherapy showed higher mortality than those without chemotherapy (P = 0·022; odds ratio 4·95). Furthermore, among the 47 patients with SJS/TEN with malignancies, lower serum albumin, haemoglobin and platelet count were detected in the deceased patients than in the surviving patients before the onset of SJS/TEN.

CONCLUSIONS

Our results suggest that several factors related to malignancies, such as specific cancer types, chemotherapy and malnutrition, may contribute to poor prognosis in patients with malignancies developing SJS/TEN.

Usefulness of Circulating Decoy Receptor 3 in Predicting Coronary Artery Disease Severity and Future Major Adverse Cardiovascular Events in Patients With Multivessel Coronary Artery Disease

Decoy receptor 3 (DcR3), a member of the tumor necrosis factor receptor superfamily, is an antiapoptotic soluble receptor considered to play an important role in immune modulation and has pro-inflammatory functions. This study was designed to test whether circulating DcR3 levels are associated with coronary artery disease (CAD) severity and predict future major adverse cardiovascular events (MACEs) in patients with CAD. Circulating DcR3 levels and the Syntax score (SXscore) were determined in patients with multivessel CAD. The primary end point was the MACE within 12 months. In total, 152 consecutive patients with angiographically confirmed multivessel CAD who had received percutaneous coronary intervention were enrolled and were divided into 3 groups according to CAD lesion severity. Group 1 was defined as low SXscore (≤13), group 2 as intermediate SXscore (>13 and ≤22), and group 3 as high SXscore (>22). DcR3 levels were significantly higher in the high SXscore group than the other 2 groups (13,602 ± 7,256 vs 8,025 ± 7,789 vs 4,637 ± 4,403 pg/ml, p <0.001). By multivariate analysis, circulating DcR3 levels were identified as an independent predictor for high SXscore (adjusted odds ratio 1.15, 95% confidence interval 1.09 to 1.21; p <0.001). The Kaplan-Meier analysis showed that increased circulating DcR3 levels are associated with enhanced 1-year MACE in patients with multivessel CAD (log-rank p <0.001). In conclusion, increased circulating DcR3 levels are associated with CAD severity and predict future MACE in patients with multivessel CAD.

Prenatal air pollutant exposure and occurrence of atopic dermatitis

BACKGROUND

Hereditary and environmental factors have been related to the occurrence of atopic dermatitis (AD) in early childhood. However, the role of prenatal and early postnatal exposure to air pollutants has not been totally elucidated.

OBJECTIVES

To evaluate the association between prenatal air pollutant exposure and occurrence of AD.

METHODS

In total 24 200 infant-mother pairs were recruited to participate in the Taiwan Birth Cohort Study in 2005 using multistage stratified sampling. Medical history, including physician-diagnosed AD, was inquired by questionnaire at the infant's age of 6 months. Monthly averages of five criteria air pollutants - NO2 , CO, O3 , SO2 and PM10 - were retrieved from 66 air-quality-monitoring stations, and interpolated to all administrative districts using the kriging method. Exposure data during each of the three gestational trimesters and three months after birth were calculated for each study subject, and odds ratios (ORs) of AD occurrence were calculated by logistic regression.

RESULTS

Among the participants, 16 686 mother-infant pairs were qualified for and included in the analysis. Among them, 1206 infants (7·2%) had been diagnosed as having AD before the age of 6 months, and the prevalence was higher in boys (8·3%) than in girls (6·1%). The occurrence of AD was significantly associated with CO exposure during the whole gestational period [adjusted OR (aOR) 1·37, 95% confidence interval (CI) 1·06-1·78] and the first trimester (aOR 1·51, 95% CI 1·16-1·97). We did not observe any significant association among the other air pollutants during either the whole gestational period or any period of the three trimesters and 3 months after birth.

CONCLUSIONS

Our study found a relationship between AD occurrence and gestational exposure to CO, where exposure during the first trimester seemed to be the most important.

Self- and rater-assessed effectiveness of "thinking-aloud" and "regular" morning report to intensify young physicians' clinical skills

BACKGROUND

This study compared the effects of the "thinking aloud" (TA) morning report (MR), which is characterized by sequential and interactive case discussion by all participants, with "regular" MR for clinical skill training of young physicians.

METHODS

Between February 2011 and February 2014, young physicians [including postgraduate year-1 (PGY1) residents, interns, and clerks) from our hospital were sequentially enrolled and followed for 3 months. The self- and rater-assessed educational values of two MR models for building up clinical skills of young physicians were compared.

RESULTS

The junior (intern and clerk) attendees had higher self-assessed educational values scores and reported post-training application frequency of skills trained by TA MR compared with the senior (PGY1 resident) attendees. Higher average and percentage of increased overall rater-assessed OSCE scores were noted among the regular MR senior attendees and TA MR junior attendees than in their corresponding control groups (regular MR junior attendees and TA MR senior attendees). Interestingly, regular MRs provided additional beneficial effects for establishing the "professionalism, consulting skills and organization efficiency" aspects of clinical skills of senior/junior attendees. Moreover, senior and junior attendees benefited the most by participating in seven sessions of regular MR and TA MR each month, respectively.

CONCLUSION

TA MR effectively trains junior attendees in basic clinical skills, whereas regular MR enhances senior attendees' "work reports, professionalism, organizational efficiency, skills in dealing with controversial and professional issues." Undoubtedly, all elements of the two MR models should be integrated together to ensure patient safety and good discipline among young physicians.

A model of four hierarchical levels to train Chinese residents' teaching skills for "practice-based learning and improvement" competency

OBJECTIVES

The current study focused on validating a protocol for training and auditing the resident's practice-based learning and improvement (PBLI) and quality improvement (QI) competencies for primary care.

METHODS

Twelve second-year (R2), 12 first-year (R1) and 12 postgraduate year-1 residents were enrolled into group A, B and C, respectively, as trainees. After three training protocols had been completed, a writing test, self-assessed questionnaire and mini-OSTE and end-of-rotation assessment were used in auditing the PBLI competency, performance and teaching ability of trainees.

RESULTS

Baseline expert-assessed PBLI and QI knowledge application tool writing scores were low for the R1 and R2 residents. After three training protocols, PBLI and QI proficiencies, performance and teaching abilities were improved to similar levels cross the three training levels of residents based on the expert-assessed writing test-audited assessments and on the faculty and standardized clerk-assessed end-of-rotation-/mini-OSTE-audited assessments.

CONCLUSION

The different four-level hierarchical protocols used to teach group A, B and C were equally beneficial and fitted their needs; namely the different levels of the trainees. Specifically, each level was able to augment their PBLI and QI proficiency. This educational intervention helps medical institutions to train residents as PBLI instructors.

Clinical and Genetic Factors Associated With Thiazide-Induced Hyponatremia

Thiazide diuretics are associated with an increased risk of hyponatremia. The aim of this study was to investigate possible predictors of thiazide-induced hyponatremia.A total of 48 patients admitted to the ward or to the emergency department due to severe thiazide-induced hyponatremia (Na < 125 mmol/L) were enrolled in our study as the case group. Another 211 hypertensive patients with normal sodium levels after treatment with thiazide diuretics were selected as the control group. Twelve tag single nucleotide polymorphism markers were selected from the Potassium Channel, Inwardly Rectifying Subfamily J, Member 1 (KCNJ1) gene: rs1231254, rs2238009, rs1148058, rs675482, rs673614, rs12795437, rs2855800, rs2509585, rs3016774, rs881333, rs4529890, and rs7116606. Clinical and genetic parameters between patients with thiazide-induced hyponatremia and the control group were compared. Logistic regression was used to analyze data.The patients with thiazide-induced hyponatremia were older (P < 0.001), predominantly female (P = 0.008), had a lower mean body mass index (BMI) (P < 0.001), and more commonly used angiotensin II receptor antagonist (P < 0.001) and spironolactone (P = 0.007) compared with the control groups. Analysis with multivariate logistic regression revealed that age (odds ratio [OR], 1.13; 95% confidence interval [CI], 1.08-1.19, P < 0.001), female gender (OR, 4.49; 95% CI, 1.54-13.11, P = 0.006), BMI (OR, 0.80; 95% CI, 0.69-0.93, P = 0.003), and KCNJ1 rs2509585 C/T or T/T polymorphisms (OR, 5.75; 95% CI, 1.25-26.45, P = 0.03) were independent predictors for thiazide-induced hyponatremia.Older female patients with lower BMIs and KCNJ1 rs2509585 C/T or T/T polymorphisms were more likely to develop thiazide-induced hyponatremia.

Estrogen-dependent sushi domain containing 3 regulates cytoskeleton organization and migration in breast cancer cells

Aromatase inhibitors (AIs) are the standard endocrine therapy for postmenopausal breast cancer; however, currently used biomarkers, such as, estrogen receptor-alpha/progesterone receptor (ERα/PR), predict only slightly more than half of the potential responders to AI treatment. To identify novel markers of AI responsiveness, a genome-wide microarray analysis was performed using primary breast tumor samples from 50 postmenopausal women who later developed metastatic breast cancer. Sushi domain containing 3 (SUSD3) is a significantly differentially expressed gene, with 3.38-fold higher mRNA levels in AI-responsive breast tumors vs non-responders (P<0.001). SUSD3 was highly expressed in ERα-positive breast tumors and treatment with estradiol increased SUSD3 expression in ERα-positive breast cancer cells. Treatment with an antiestrogen or ERα knockdown abolished basal and estradiol-dependent SUSD3 expression. Recruitment of ERα upstream of the transcription start site of SUSD3 was demonstrated by chromatin immunoprecipitation-PCR. Flow cytometric analysis of SUSD3-knockdown cells revealed blunted estradiol effects on progression into S and M phases. SUSD3 was localized to the plasma membrane of breast cancer cells. SUSD3 knockdown decreased the appearance of actin-rich protrusions, stress fibers and large basal focal adhesions, while increasing the presence of cortical actin concomitant with a decrease in Rho and focal adhesion kinase activity. SUSD3-deficient cells demonstrated diminished cell spreading, cell-cell adhesion and motility. In conclusion, SUSD3 is a novel promoter of estrogen-dependent cell proliferation and regulator of cell-cell and cell-substrate interactions and migration in breast cancer. It may serve as a novel predictor of response to endocrine therapy and potential therapeutic target.

An isolated intracranial mucocoele herniated from the frontal sinus

Mucocoeles are chronic mucosa-lined retention cysts that occur due to sinus ostium obstruction and expand along the path of least resistance, most commonly involving the frontal sinus. A frontal mucocoele typically appears as a smooth and rounded expansile enlargement of a completely opacified frontal sinus, with or without thinning of the bony wall of the sinus. Here we report a rare case of isolated intracranial mucocoele that presented with posterior herniation to the anterior cranial fossa through a small bony defect on the posterior table of the frontal sinus. The findings upon imaging could easily be confused with intracranial abscess, potentially leading to craniotomy drainage. In the present case of mucocoele, the frontal intracranial lesion was completely resolved following endoscopic frontal sinusotomy.

Metformin use in patients with type 2 diabetes mellitus is associated with reduced risk of deep vein thrombosis: a non-randomized, pair-matched cohort study

Background

Metformin, an insulin-sensitizer, may correct several physiologic abnormalities owing to insulin resistance in patients with type 2 diabetes mellitus (DM). The effects of metformin on venous thrombosis in patient with type 2 DM have not been reported. Our study strived to explore the relationship of metformin therapy and the subsequent development of deep vein thrombosis (DVT) using a nationwide, population-based database.

Methods

From 1997 to 2003, we identified a study cohort consisting of patients with type 2 DM using metformin 7154 cases in the National Health Insurance Research Database. A control cohort without metformin, matched for age, sex, comorbidities, and medications was selected for comparison.

Results

Of the 14945 patients (7167 patients with metformin vs. 7778 control), 60 (0.40%) patients developed DVT during a mean follow-up period of 3.74 years, including 16 (0.21%) from the cohort with metformin and 44 (0.56%) from the control group. Subjects with metformin experienced a 0.427 fold (95% confidence interval 0.240-0.758; P = 0.004) changes of risk reduction in development of DVT, which was independent of age, sex and co-morbidities. Kaplan-Meier analysis also revealed metformin therapy is associated with lower occurrence of DVT (log-rank test, P = 0.001).

Conclusions

Metformin may have protective effect in patients with type 2 DM for DVT.

YM155 down-regulates survivin and XIAP, modulates autophagy and induces autophagy-dependent DNA damage in breast cancer cells

BACKGROUND AND PURPOSE

The aim of this study was to determine the potency and molecular mechanism of action of YM155, a first-in-class survivin inhibitor that is currently under phase I/II clinical investigations, in various drug-resistant breast cancers including the oestrogen receptor positive (ER(+) ) tamoxifen-resistant breast cancer and the caspase-3-deficient breast cancer.

EXPERIMENTAL APPROACH

The potency of YM155 in SK-BR-3, MDA-MB-231, MCF7 and its tamoxifen-resistant sublines, TamR6, TamR7, TamR8, TamC3 and TamC6, were determined by MTT assay. Western blot analysis, flow cytometric analysis, reverse transcription-PCR, fluorescent microscopy and comet assay were used to determine the molecular mechanism of action of YM155 in different breast cancer cell lines.

KEY RESULTS

YM155 was equally potent towards the parental ER(+) /caspase-3-deficient MCF7 breast cancer cells and its tamoxifen-resistant sublines in vitro. The ER(-) /HER2(+) SK-BR-3 breast cancer cells and the triple-negative/caspase-3-expressing metastatic aggressive MDA-MB-231 breast cancer cells were also sensitive to YM155 with IC50 values in the low nanomolar range. Targeting survivin by YM155 modulated autophagy, induced autophagy-dependent caspase-7 activation and autophagy-dependent DNA damage in breast cancer cells. Interestingly, YM155 also induced XIAP degradation and the degradation of XIAP might play an important role in YM155-induced autophagy in breast cancer cells.

CONCLUSIONS AND IMPLICATIONS

YM155 is a potent survivin inhibitor that has potential for the management of various breast cancer subtypes regardless of the expression of ER, HER2 and caspase-3. Importantly, this study provides new insights into YM155's molecular mechanism of action and therapeutic potential in the treatment of tamoxifen-resistant breast cancer.