Lower HbA1C of glycemic control is associated with higher risk of depressive symptoms in elderly with type 2 diabetes mellitus-A Nationwide Community-based study

OBJECTIVE

We investigated the correlation between glycemic control status and depressive symptoms in type 2 diabetes elderly.

METHODS

A total of 1527 participants with type 2 diabetes aged 55 years and older from the Healthy Aging Longitudinal Study in Taiwan study were included in this cross-sectional study. The Center for Epidemiologic Studies Depression Scale (CESD) (20 items) score of ≥16 was indicative of depressive symptoms. The participants were divided into HbA1c ≥ 6.5% and < 6.5% representing the glycemic control. Multiple logistic regression (MLR) and Generalized linear model (GLM) were used.

RESULTS

The MLR analysis showed that the low HbA1c group had significant two-fold increased odds of depressive symptoms compared to the high HbA1c group (OR 1.89, 95% CI 1.17-3.05). The risk of depressive symptoms was lower among males (OR 0.49, 95% CI 0.30-0.80) and those with higher BMI (OR 0.93, 95% CI 0.86-1.00); whereas the risk was higher among those who lived alone (OR 2.37, 95% CI 1.31-4.27) and with ADL disability (OR 3.01, 95% CI 1.85-4.89). The GLM showed that the dimension of depressive affect reached statistical significance with lower HbA1c.

CONCLUSION

This nationwide community-based study shows that depressive symptoms are associated with lower HbA1C, reminding us that more attention should be paid to the presence of depressive symptoms in those with lower HbA1C. Further research is needed to clarify the causal relationship.

Association of leukocyte mitochondrial DNA copy number with longitudinal C-reactive protein levels and survival in older adults: a cohort study

BACKGROUND

Systemic chronic inflammation occurs with age. The association of the leukocyte mitochondrial DNA copy number, a measure of mitochondrial function in aging, with the temporal profile of serum high-sensitivity C-reactive protein and mortality risk remains uncertain. The objectives of this study were to examine the association of the leukocyte mitochondrial DNA copy number with longitudinal high-sensitivity C-reactive protein levels and the association of the longitudinal high-sensitivity C-reactive protein levels with mortality risk.

METHODS

This prospective cohort study included 3928 adults aged ≥ 55 years without systemic inflammation in the baseline examination of the Healthy Aging Longitudinal Study in Taiwan, which started in 2009. Each participant received leukocyte mitochondrial DNA copy number measurement using a fluorescence-based quantitative polymerase chain reaction at baseline, serum high-sensitivity C-reactive protein measurements at baseline and the follow-up examination five years later, and the ascertainment of all-cause death (until November 30, 2021). The relationships among the leukocyte mitochondrial DNA copy number, longitudinal serum high-sensitivity C-reactive protein levels, and time to all-cause mortality were examined using the joint longitudinal and survival modeling analysis.

RESULTS

Of the 3928 participants (mean age: 69 years; 2060 [52%] were women), 837 (21%) died during follow-up. In the adjusted analysis, one standard deviation lower natural log-transformed baseline leukocyte mitochondrial DNA copy number was associated with an increase of 0.05 (95% confidence interval [CI], 0.02 to 0.08) standard deviation in serum high-sensitivity C-reactive protein in subsequent years. An increase of 1 standard deviation in instantaneous high-sensitivity C-reactive protein levels was associated with a hazard ratio (HR) for all-cause mortality of 1.22 (95% CI, 1.14 to 1.30). Similar results were obtained after further adjusting for baseline high-sensitivity C-reactive protein levels (HR [95% CI], 1.27 [1.16 to 1.38]) and after excluding those with serum high-sensitivity C-reactive protein above 10 mg/L (HR [95% CI], 1.21[1.11 to 1.31]) or 3 mg/L (HR [95% CI], 1.19 [1.06 to 1.31]) during follow-up.

CONCLUSIONS

A lower leukocyte mitochondrial DNA copy number was associated with persistently higher high-sensitivity C-reactive protein levels. Moreover, these higher time-varying high-sensitivity C-reactive protein levels were instantaneously associated with a higher risk of death.

Artificial Intelligence-Enabled Model for Early Detection of Left Ventricular Hypertrophy and Mortality Prediction in Young to Middle-Aged Adults

BACKGROUND

Concealed left ventricular hypertrophy (LVH) is a prevalent condition that is correlated with a substantial risk of cardiovascular events and mortality, especially in young to middle-aged adults. Early identification of LVH is warranted. In this work, we aimed to develop an artificial intelligence (AI)-enabled model for early detection and risk stratification of LVH using 12-lead ECGs.

METHODS

By deep learning techniques on the ECG recordings from 28 745 patients (20-60 years old), the AI model was developed to detect verified LVH from transthoracic echocardiography and evaluated on an independent cohort. Two hundred twenty-five patients from Japan were externally validated. Cardiologists' diagnosis of LVH was based on conventional ECG criteria. The area under the curve (AUC), sensitivity, and specificity were applied to evaluate the model performance. A Cox regression model estimated the independent effects of AI-predicted LVH on cardiovascular or all-cause death.

RESULTS

The AUC of the AI model in diagnosing LVH was 0.89 (sensitivity: 90.3%, specificity: 69.3%), which was significantly better than that of the cardiologists' diagnosis (AUC, 0.64). In the second independent cohort, the diagnostic performance of the AI model was consistent (AUC, 0.86; sensitivity: 85.4%, specificity: 67.0%). After a follow-up of 6 years, AI-predicted LVH was independently associated with higher cardiovascular or all-cause mortality (hazard ratio, 1.91 [1.04-3.49] and 1.54 [1.20-1.97], respectively). The predictive power of the AI model for mortality was consistently valid among patients of different ages, sexes, and comorbidities, including hypertension, diabetes, stroke, heart failure, and myocardial infarction. Last, we also validated the model in the international independent cohort from Japan (AUC, 0.83).

CONCLUSIONS

The AI model improved the detection of LVH and mortality prediction in the young to middle-aged population and represented an attractive tool for risk stratification. Early identification by the AI model gives every chance for timely treatment to reverse adverse outcomes.

Artificial Intelligence-Enabled Electrocardiogram Improves the Diagnosis and Prediction of Mortality in Patients With Pulmonary Hypertension

BACKGROUND

Pulmonary hypertension is a disabling and life-threatening cardiovascular disease. Early detection of elevated pulmonary artery pressure (ePAP) is needed for prompt diagnosis and treatment to avoid detrimental consequences of pulmonary hypertension.

OBJECTIVES

This study sought to develop an artificial intelligence (AI)-enabled electrocardiogram (ECG) model to identify patients with ePAP and related prognostic implications.

METHODS

From a hospital-based ECG database, the authors extracted the first pairs of ECG and transthoracic echocardiography taken within 2 weeks of each other from 41,097 patients to develop an AI model for detecting ePAP (PAP > 50 mm Hg by transthoracic echocardiography). The model was evaluated on independent data sets, including an external cohort of patients from Japan.

RESULTS

Tests of 10-fold cross-validation neural-network deep learning showed that the area under the receiver-operating characteristic curve of the AI model was 0.88 (sensitivity 81.0%; specificity 79.6%) for detecting ePAP. The diagnostic performance was consistent across age, sex, and various comorbidities (diagnostic odds ratio >8 for most factors examined). At 6-year follow-up, the patients predicted by the AI model to have ePAP were independently associated with higher cardiovascular mortality (HR: 3.69). Similar diagnostic performance and prediction for cardiovascular mortality could be replicated in the external cohort.

CONCLUSIONS

The ECG-based AI model identified patients with ePAP and predicted their future risk for cardiovascular mortality. This model could serve as a useful clinical test to identify patients with pulmonary hypertension so that treatment can be initiated early to improve their survival prognosis.

[Clinical efficacy of transjugular intrahepatic portosystemic shunt for gastrointestinal hemorrhage in patients with idiopathic noncirrhotic portal hypertension]

Objective: To explore the medium-long term efficacy of transjugular intrahepatic portosystemic shunt (TIPS) for gastrointestinal hemorrhage in patients with idiopathic non-cirrhotic portal hypertension (INCPH). Methods: From March 2013 to July 2018, clinical data of 13 INCPH patients, including 5 males, 8 females,with gastrointestinal hemorrhage were retrospectively analyzed, who were diagnosed at the First Affiliated Hospital of Zhengzhou University, Anyang Fifth People' s Hospital and Yuncheng Central Hospital. All patients received TIPS treatment. The general information, postoperative survival rate, the incidence of rebleeding, shunt dysfunction rate, and incidence of hepatic encephalopathy were analyzed. Results: All 13 patients with INCPH completed TIPS successfully with an average age of 45±8 (33 to 59) years. The hepatic venous pressure gradient (HVPG) decreased from 20.0-26.0 (22.6±1.9) mmHg before procedure to 8.0-14.0 (9.4±3.2) mmHg after. The median follow-up time was 44±7 (31 to 53) months. One patient died of liver failure 27 months after TIPS. Hepatic encephalopathy occurred cumulatively in 1 case (1/13), 1 case (1/13) and 1 case (1/13) in 12, 24 and 36 months after TIPS. Stent restenosis occurred cumulatively in 2 cases (2/13), 3 cases (3/13) and 3 cases (3/13) in 12, 24 and 36 months after TIPS. Portal vein thrombosis occurred cumulatively in 2 cases (2/13), and no primary liver cancer developed. Conclusions: TIPS is safe and effective in the treatment of INCPH with gastrointestinal bleeding with favorable medium-long term outcome.

Exercise Test for Patients with Long QT Syndrome

Congenital long QT syndrome (LQTS) causes life-threatening cardiac arrhythmias and is the leading cause of sudden cardiac death in young people. Measurements of QT prolongation during exercise or postural change have been recommended to assist in the diagnosis of LQTS, particularly in those with hidden phenotypes. However, most evidence has come from single-center studies without external validation in an independent cohort. Inter-study heterogeneity leads to significant difficulties in interpreting and applying consistent diagnostic criteria for LQTS. A comprehensive systematic review is critically needed to summarize the evidence and validate the diagnostic performance of QT intervals during exercise or postural change across a variety of studies. In this study, we review cross-sectional and cohort studies evaluating the efficacy and feasibility of exercise tests or postural changes in diagnosing LQTS, and propose possible problems resulting from exercise tests.

[Clinical value of emergency endovascular embolization in the interventional treatment for oral hemorrhage caused by carcinoma]

To evaluate the clinical value of emergency endovascular embolization in the interventional treatment for oral hemorrhage caused by carcinoma, 32 patients with oral hemorrhage caused by carcinoma, who received emergency endovascular embolization due to unsatisfactory hemostatic effect of conventional conservative treatment in the First Affiliated Hospital of Zhengzhou University from January 2014 to December 2019, were included in this study and their clinical data, laboratory data and imaging information were retrospectively analyzed. There were 16 males and 16 females, aged (60.6±13.6) years (34-88 years). Technical successful rate of emergency endovascular embolization, immediate successful rate of controlling hemorrhage, blood pressure before and after operation, hemoglobin before and after operation, postoperative complications and recurrence rate of oral hemorrhage were statistically analyzed. Results showed that technical successful rate of operation and immediate successful rate of controlling oral hemorrhage are both 100% (32/32). Recurrent oral hemorrhage occurred in 4 patients (13%). The hemorrhagic shock symptoms of all patients were significantly improved after interventional therapy. After operation, local swelling happened in 34% (11/32) patients and intermittent local pain happened in 22% (7/32) within 24 hours; the swelling and the pain gradually disappeared from 2nd to 5th days. Mild complications of transient fever happened in 9% (3/32) patients and disappeared spontaneously in the short term. No serious complications such as blindness, cerebrovascular accident or central nervous system disturbance occurred in all patients after operations. During the whole follow-up period (1 to 12 months), a total of 8 patients died. The causes of death were progression and metastasis of carcinoma (n=4), heart failure (n=2), severe pneumonia (n=1) and respiratory failure caused by recurrent oral hemorrhage (n=1). Owing to the remarkable short-term curative effect, repeatable operation, low recurrence rate of oral hemorrhage and low incidence of complications, emergency endovascular embolization can be used in the clinical therapy and application of oral hemorrhage caused by carcinoma.

Virus load and virus shedding of SARS-CoV-2 and their impact on patient outcomes

BACKGROUND

Understanding a virus shedding patterns in body fluids/secretions is important to determine the samples to be used for diagnosis and to formulate infection control measures.

AIM

To investigate the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) shedding patterns and its risk factors.

METHODS

All laboratory-confirmed coronavirus disease 2019 patients with complete medical records admitted to the Shenzhen Third People’s Hospital from January 28, 2020 to March 8, 2020 were included. Among 145 patients (54.5% males; median age, 46.1 years), three (2.1%) died. The bronco-alveolar lavage fluid (BALF) had the highest virus load compared with the other samples. The viral load peaked at admission (3.3 × 10⁸ copies) and sharply decreased 10 d after admission.

RESULTS

The viral load was associated with prolonged intensive care unit (ICU) duration. Patients in the ICU had significantly longer shedding time compared to those in the wards (P < 0.0001). Age > 60 years [hazard ratio (HR) = 0.6; 95% confidence interval (CI): 0.4-0.9] was an independent risk factor for SARS-CoV-2 shedding, while chloroquine (HR = 22.8; 95%CI: 2.3-224.6) was a protective factor.

CONCLUSION

BALF had the highest SARS-CoV-2 load. Elderly patients had higher virus loads, which was associated with a prolonged ICU stay. Chloroquine was associated with shorter shedding duration and increased the chance of viral negativity.

[Clinical application and efficacy of TIPS combined with AngioJet mechanical thrombectomy for liver cirrhosis with extensive portal vein thrombosis]

Objective: To assess the safety and efficacy of transjugular intrahepatic portosystemic shunt (TIPS) combined with AngioJet mechanical thrombectomy for liver cirrhosis with extensive portal vein thrombosis. Methods: From March 2018 to April 2019, a total of 11 patients with liver cirrhosis and extensive portal vein thrombosis were treated by TIPS combined with AngioJet mechanical thrombectomy, including 6 males and 5 females, with the age of 37-71 (46±9) years old, 3 cases of Child-Pugh grade A, 8 cases of grade B and 0 cases of grade C. The intraoperative immediate thrombus clearance rate, perioperative complication rate, postoperative thrombus recurrence rate, rebleeding rate, the incidence of hepatic encephalopathy and the rate of stent patency of all cases were collected and analyzed. Results: All the patients were treated successfully. The immediate complete thrombus clearance (grade Ⅲ) rate of portal vein trunk was 9/11, and grade Ⅱ was 2/11, The average dose of urokinase was 30-60 (40±5) ten thousand U, slight puncture point bleeding occurred in 3 cases, and recurrence of PVT in portal vein trunk occurred in 1 case with Ⅱ grade clearance rate after operation, rebleeding occurred in 1 case, hepatic encephalopathy occurred in 2 cases, the primary patency rate of stents was 9 cases. Conclusion: TIPS combined with AngioJet mechanical thrombectomy can treat the liver cirrhosis with extensive portal vein thrombosis effectively and safely, and postoperative portal vein patency rate and intrahepatic shunt patency rate are high.

The presence of ectopic atrial rhythm predicts adverse cardiovascular outcomes in a large hospital-based population

BACKGROUND

Whether ectopic atrial rhythm (EAR) is a high-risk cardiovascular phenotype (eg, the manifestation of a diseased sinoatrial node) or just a benign accelerated ectopic pacemaker remains unclear.

OBJECTIVE

We aimed to analyze the cardiovascular outcomes and underlying mechanisms in patients with EAR.

METHODS

From a 12-lead electrocardiogram hospital-based electrocardiogram database, a total of 2896 adults with EAR were propensity score matched at 1:5 with 14,480 patients with sinus rhythm (SR). Patients were retrospectively followed up for cardiovascular mortality (the primary outcome) and permanent pacemaker implantation (the secondary outcome). Heart rate variability was analyzed to compare autonomic function between patients with EAR and those with SR.

RESULTS

The prevalence of EAR was 1.13%, which increased with age. Compared with the matched patients, those with EAR had a higher risk of cardiovascular mortality (adjusted hazard ratio 1.93; 95% confidence interval 1.52-2.44; P < .0001) and permanent pacemaker implantation (adjusted hazard ratio 5.94; 95% confidence interval 3.89-9.09; P < .0001) according to the Cox proportional hazards regression model. The risk of cardiovascular mortality was similar across the subgroups on the basis of age, sex, hypertension, type 2 diabetes mellitus, congestive heart failure, myocardial infarction, stroke, and chronic kidney diseases. In patients with EAR, the low frequency/high frequency and standard deviation of the mean normal-to-normal intervals/root mean square of successive RR interval differences ratios for heart rate variability were both lower than those in patients with SR. This implied autonomic imbalance in patients with EAR.

CONCLUSION

Patients with EAR have a higher risk of cardiovascular mortality and permanent pacemaker implantation, which was associated with autonomic imbalance.

[Application of real-time image fusion technique in transjugular intrahepatic portosystemic shunt]

Objective: To assess the feasibility and value of real-time image fusion technique guiding the procedure of transjugular intrahepatic portosystemic shunt(TIPS). Methods: From July 2017 to May 2018,a total of 48 consecutive patients complicated by portal venous hypertension due to cirrhosis who underwent TIPS were prospectively allocated into two groups that 27 cases underwent normal TIPS and 21 cases underwent image fusion guided TIPS. There were 25 males and 23 females with a mean age of 29-74(51±10) years. The differences of portal vein(PV) between image fusion angiographyand digital subtraction angiography(DSA), and the times of puncture PV, X-ray exposure dose and exposure time and contrast agent amount of all cases were collected and analyzed. Results: The longitudinal and traverse difference of PV between image fusion angiography and DSA were 1.7-2.5(2.1±0.2) mm and 0.9-1.8(1.4±0.3) mm, respectively.The times of puncture PV, X-ray exposure time and dose, and contrast agent amount between normal TIPS group and image fusion guided TIPS group were 1-7(3.8±0.6) times vs 1-3(2.0±0.6) times, 41-63(53±8)min vs 27-42(35±5) min, 513-787(644±96) mGy vs 357-524(423±59) mGy,102-196(151±23) ml vs 87-145(105±14) ml(all P<0.05), respectively. Conclusions: There are minor differences between image fusion angiography of PV and DSA. Real-time image fusion guided TIPS is feasible and valuable to reduce intraprocedural X-ray exposure time and dose and contrast agent amount of TIPS.

Vessel traffic safety in busy waterways: A case study of accidents in western shenzhen port

Throughout the world, busy waterways near large ports witness heavy vessel traffic in recent decades. The waterways are characterized by high risk in terms of loss of life, property, and pollution to environment. To facilitate maritime safety management with satisfactory efficiency and efficacy, the authors propose a framework of safety indexes to evaluate the risk level in busy waterways according to the accident severity, fatality rate and special indicators of maritime transportation. The safety indexes consist of Safety Evaluation Index (SEI) and Safety Warning Index (SWI), and are derived from the proposed risk criteria of Chinese vessel traffic. As a case study, data on vessel traffic accidents reported in the Western Shenzhen Port, South China from 1995 to 2015 are analyzed. The actual risk level of this area during the period is calculated under the framework. The implementation of the safety indexes indicate that the risk criteria and safety indexes are practicable and effective for the vessel traffic management. The methodology based on long-term accident data can significantly support the risk analysis in the macroscopic perspective for busy ports and waterways, such that SWI can act as threshold to trigger actions, while SEI can act as an indicator to measure safety status.

A circular white-light flare with impulsive and gradual white-light kernels

White-light flares are the flares with emissions visible in the optical continuum. They are thought to be rare and pose the most stringent requirements in energy transport and heating in the lower atmosphere. Here we present a nearly circular white-light flare on 10 March 2015 that was well observed by the Optical and Near-infrared Solar Eruption Tracer and Solar Dynamics Observatory. In this flare, there appear simultaneously both impulsive and gradual white-light kernels. The generally accepted thick-target model would be responsible for the impulsive kernels but not sufficient to interpret the gradual kernels. Some other mechanisms including soft X-ray backwarming or downward-propagating Alfvén waves, acting jointly with electron beam bombardment, provide a possible interpretation. However, the origin of this kind of white-light kernel is still an open question that induces more observations and researches in the future to decipher it.

[Road-side observational survey on 4 unlawful acts among electric bicycle riders in Zhejiang]

OBJECTIVE

To investigate the prevalence of key unlawful acts among electric bicycle riders and provide evidence for the development of specific interventions.

METHODS

A 4-day road-side survey was conducted in Jinhua, Zhejiang province, in 2013. The speed of electric bicycle was measured by speed measuring instrument and the unlawful acts of riders, such as reverse riding, running the red-light and carrying passengers, were observed with non-participatory way.

RESULTS

A total of 3 448 running electric bicycles were observed and the average speed was 26 km/h, the proportion of electric bicycle at the speed of ≥15 km/h was 87.06%. The average speed was highest during 10 am-11 am(30 km/h). the number of observed electric bicycle riders with unlawful acts of ' running the red-light','reverse riding' and ' carrying passengers' were 1 315, 656 and 1 877 respectively, and the estimated rate was 10.01%, 4.99% and 15.22%, respectively. More ' running the red-light','reverse riding' and ' carrying passengers' occurred during 7 am-8 am(14.59%)and 13 pm-14 pm(15.25%), 13 pm-14 pm(7.33%)and 17 pm-18 pm(7.63%), 6 am-7 am(32.44%)and 12 pm-13 pm(27.90%), respectively.

CONCLUSION

Overspeeding, carrying passengers, running the red-light, reverse riding were the key unlawful acts among electric bicycle riders. Targeted intervention should be carried out to reduce the prevalence of unlawful riding acts and the incidence of electric bicycle related injuries and deaths.

Sirtuin 3 Protects against Urban Particulate Matter-Induced Autophagy in Human Bronchial Epithelial Cells

Urban particulate matter (urban PM) is a heterogeneous mixture of various types of particles originating from different sources. Exposure to high concentrations of urban PM leading to adverse health effects is evaluated by using in vitro cultures of human lung epithelial cells. However, the mechanism underlying the correlation between high concentrations of urban PM exposure and adverse health effects has not been fully elucidated; urban PM-induced oxidative stress is considered as an important mechanism of urban PM-mediated cytotoxicity. Sirtuin 3 (SIRT3), a primary mitrochondrial deacetylase, controls cellular reactive oxygen species (ROS) production, and expression of antioxidant enzymes. In this study, we examined the role of SIRT3 in the regulation of urban PM-induced oxidative stress in normal primary human bronchial epithelial cells (HBEpiCs). Cell viability showed a time- and concentration-dependent decrease when exposed to urban PM, which could indicate that the amount of lactate dehydrogenase released from the cell in response to urban PM is related to cell viability in HBEpiC. The effects of urban PM on morphological and biochemical markers of autophagy in HBEpiC were analyzed by electron microscopy and Western blotting. Overexpression of SIRT3 inhibited urban PM-induced ROS generation, while concomitantly increasing the expression of antioxidant enzymes, and decreasing NF-κB activation and release of inflammation factors. Up-regulation of SIRT3 significantly inhibited the expression of autophagy markers and autophagic vacuole formation. Our findings provide a valuable insight into the potential role of the SIRT3 enzyme in regulating urban PM-induced autophagy by mediating urban PM-induced oxidative stress, which may contribute to urban PM-induced impairment of airway epithelial cell function.

The end-of-treatment telephone response and prognosis of post-radiotherapy nasopharyngeal carcinoma patients in southern China

Nasopharyngeal Carcinoma (NPC) patients' end-of-treatment survival status has drawn more attention in recent years. Telephone follow-up, as a most operative approach among all the clinical follow-ups, is an effective means to extend medical service to patients' home and is thus widely used in clinical practice. This study aimed to analyze the post-radiotherapy NPC patients' phone response rate and its factors, and to discuss the independent prognostic factors of NPC patients' radiotherapy. We prospectively designed a nurses-led telephone follow-up to include 2520 NPC patients who received simple radical radiotherapy between Jan. 2007 and Jun. 2012 at Sun Yat-sen University Cancer Center. The patients' response rate and its factors were calculated. Survival analysis was used to estimate the patients' survival and the influencing factors. The overall response rate was 90.5%; Patients with reserved contact type of mobile + landlinephone or landline phone had higher follow-up response rate than patients with mobile contact only; patients with 2 or more reserved contacts, and family cancer history had higher response rate than patients with only 1 number and those without family history. Patients' cumulative survival rate of 1, 3 and 5 years were 98.9%, 75.3%, 50.3%, respectively. T-staging, N-staging, higher clinical staging, with basicranial invasion were the influencing factors of the patients' poor prognosis. The telephone follow-up response was affected by reserved contact type, number of contacts and family medical history; T-staging, N-staging, higher clinical staging, with basicranial invasion were the influencing factors of the patients' poor prognosis. This study provides a scientific basis for increasing the NPC patients' end-of-treatment response and promoting the individualized clinical treatment.

Association Between the CYP1B1 Polymorphisms and Lung Cancer Risk: A Meta-Analysis

The previously published data on the association between the cytochrome P450 1B1 Leu432Val, Asn453Ser, and Ala119Ser polymorphisms and lung cancer risk have remained controversial. Hence, we performed a meta-analysis to investigate the association between cytochrome P450 1B1 Leu432Val, Asn453Ser, and Ala119Ser polymorphisms and lung cancer risk under different inheritance models. A total of 22 studies were identified, including 2881 cases and 3653 controls for Leu432Val polymorphism (from 13 studies), 3009 cases and 3887 controls for Asn453Ser polymorphism (from 5 studies), and 1301 cases and 2045 controls for Ala119Ser polymorphism (from 4 studies). Overall, significant association was observed between cytochrome P450 1B1 Leu432Val polymorphism and lung cancer risk (dominant model: odds ratio = 1.29, 95% confidence interval = 1.08-1.53; recessive model: odds ratio = 1.21, 95% confidence interval = 1.05-1.39; additive model: odds ratio = 1.43, 95% confidence interval = 1.21-1.69) when all the eligible studies were pooled into the meta-analysis. In the further stratified and sensitivity analyses, significantly increased lung cancer risk was also observed in caucasians and smokers. No significant association was observed between cytochrome P450 1B1Asn453Ser and Ala119Ser polymorphisms and lung cancer risk in overall analysis. In summary, this meta-analysis suggests that cytochrome P450 1B1Leu432Val polymorphism is associated with increased lung cancer risk in caucasians and smokers.

Extreme ultraviolet imaging of three-dimensional magnetic reconnection in a solar eruption

Magnetic reconnection, a change of magnetic field connectivity, is a fundamental physical process in which magnetic energy is released explosively, and it is responsible for various eruptive phenomena in the universe. However, this process is difficult to observe directly. Here, the magnetic topology associated with a solar reconnection event is studied in three dimensions using the combined perspectives of two spacecraft. The sequence of extreme ultraviolet images clearly shows that two groups of oppositely directed and non-coplanar magnetic loops gradually approach each other, forming a separator or quasi-separator and then reconnecting. The plasma near the reconnection site is subsequently heated from ∼1 to ≥5 MK. Shortly afterwards, warm flare loops (∼3 MK) appear underneath the hot plasma. Other observational signatures of reconnection, including plasma inflows and downflows, are unambiguously revealed and quantitatively measured. These observations provide direct evidence of magnetic reconnection in a three-dimensional configuration and reveal its origin.

Magnetic reconnection is a fundamental energy release process taking place in various astrophysical environments, but it is difficult to observe it directly. Here, the authors provide evidence of three-dimensional magnetic reconnection in a solar eruption using combined perspectives of two spacecraft.

Role of SIRT1 in regulation of epithelial-to-mesenchymal transition in oral squamous cell carcinoma metastasis

BACKGROUND

The epithelial-to-mesenchymal transition (EMT) process results in a loss of cell-cell adhesion, increased cell mobility, and is crucial for enabling the metastasis of cancer cells. Recently, the enzyme SIRT1 has been implicated in a variety of physiological processes; however, its role in regulating oral cancer metastasis and EMT is not fully elucidated. Here, we propose a mechanism by which the enzyme sirtuin1 (SIRT1) regulates the EMT process in oral cancer by deacetylating Smad4 and repressing the effect of TGF-β signaling on matrix metalloproteinase-7 (MMP7).

METHODS

The roles of SIRT1 in tumor cell migration/invasion and metastasis to the lungs were investigated using the Boyden chamber assay and orthotopic injections, respectively. RNA interference was used to knockdown either SIRT1 or Smad4 expression in oral squamous cell carcinoma (OSCC) cell lines. Immunoblotting, zymographic assays, and co-immunoprecipitation were used to examine the effects of SIRT1 overexpression on MMP7 expression and activity, as well as on SIRT1/ Smad4 interaction.

RESULTS

We found that compared with normal human oral keratinocytes (HOKs), SIRT1 was underexpressed in OSCC cells, and also in oral cancer tissues obtained from 14 of 21 OSCC patients compared with expression in their matched normal tissues. Overexpression of SIRT1 inhibited migration of OSCC cells in vitro, as well as their metastasis to the lung in vivo. Furthermore, up-regulation of SIRT1 in metastatic OSCCs significantly inhibited the migration and invasion abilities of OSCC cells, while concomitantly increasing the expression of E-cadherin, and decreasing the expressions of mesenchymal markers. We also identified Smad4, a TGF-β-activated transcription factor, as a direct target protein for SIRT1. Overexpression of SIRT1 in OSCC cells led to decreased levels of acetylated Smad4, and inhibition of TGF-β-induced signaling. By associating and deacetylating Smad4, SIRT1 enzyme can influence MMP7 expression, MMP enzyme activity, and consequently, cell migration, invasion, and tumor metastasis in OSCCs.

CONCLUSIONS

These findings provide a valuable insight into the potential role of the SIRT1 enzyme in regulating cell migration and invasion in oral squamous cell carcinoma. Our findings suggest the SIRT1/Smad4/MMP7 pathway as a target for oral cancer driven by EMT.

STRESS-responsive deacetylase SIRT3 is up-regulated by areca nut extract-induced oxidative stress in human oral keratinocytes

Areca chewing is an important environmental risk factor for development of oral premalignant lesions and cancer. Epidemiological evidence indicates that areca chewing is tightly linked to oral carcinogenesis. However, the pathogenetic impacts of areca nut extract (ANE) on normal human oral keratinocytes (HOKs) are unclear and possibly involve oxidative stress via redox imbalance. Sirtuin 3 (SIRT3) is a member of the sirtuin family of proteins that play an important role in regulating cellular reactive oxygen species (ROS) production. Recent studies have confirmed that ANE and other areca ingredients can induce ROS. In this study, we examined the role of SIRT3 in the regulation of ANE-induced ROS in HOK cells. We examined HOK cell viability following treatment with various ANE concentrations. ANE-induced cytotoxicity increased in a dose-dependent manner and was approximately 48% at a concentration of 50 μg/ml after 24 h. SIRT3 expression and enzyme activity were up-regulated in HOK cells by ANE-induced oxidative stress. Additionally, we identified that SIRT3 controls the enzymatic activity of mitochondrial proteins, such as forkhead box O3a (Foxo3a) transcription factor and antioxidant-encoding gene superoxide dismutase 2 (SOD2), by deacetylation in HOK cells. Moreover, SIRT3-mediated deacetylation and activation of Foxo3a promotes nuclear localization in vivo. These findings suggest that SIRT3 is an endogenous negative regulator in response to ANE-induced oxidative stress and demonstrate an essential role for redox balance in HOK cells.

Andrographolide downregulates the v-Src and Bcr-Abl oncoproteins and induces Hsp90 cleavage in the ROS-dependent suppression of cancer malignancy

Andrographolide is a diterpenoid compound isolated from Andrographis paniculata that exhibits anticancer activity. We previously reported that andrographolide suppressed v-Src-mediated cellular transformation by promoting the degradation of Src. In the present study, we demonstrated the involvement of Hsp90 in the andrographolide-mediated inhibition of Src oncogenic activity. Using a proteomics approach, a cleavage fragment of Hsp90α was identified in andrographolide-treated cells. The concentration- and time-dependent induction of Hsp90 cleavage that accompanied the reduction in Src was validated in RK3E cells transformed with either v-Src or a human truncated c-Src variant and treated with andrographolide. In cancer cells, the induction of Hsp90 cleavage by andrographolide and its structural derivatives correlated well with decreased Src levels, the suppression of transformation, and the induction of apoptosis. Moreover, the andrographolide-induced Hsp90 cleavage, Src degradation, inhibition of transformation, and induction of apoptosis were abolished by a ROS inhibitor, N-acetyl-cysteine. Notably, Hsp90 cleavage, decreased levels of Bcr-Abl (another known Hsp90 client protein), and the induction of apoptosis were also observed in human K562 leukemia cells treated with andrographolide or its active derivatives. Together, we demonstrated a novel mechanism by which andrographolide suppressed cancer malignancy that involved inhibiting Hsp90 function and reducing the levels of Hsp90 client proteins. Our results broaden the molecular basis of andrographolide-mediated anticancer activity.

Role of SIRT3 in the regulation of redox balance during oral carcinogenesis

BACKGROUND

Sirtuins (SIRT1-7) are a family of NAD-dependent deacetylases, which play an important role in regulating cancer tumorigenesis; however, their role in oral cancer has been controversial. SIRT3 is localized in the mitochondria, where it deacetylates and activates several enzymes involved in cellular redox balance and defense against oxidative damage.

RESULTS

We found that compared with normal human oral keratinocytes (HOK), SIRT3 is highly expressed in oral squamous cell carcinoma (OSCC) cell lines, but the enzymatic deacetylation is significantly reduced. We also sequenced the entire coding region of SIRT3 and found the same mutation in 2 different OSCC cell lines. This point mutation is located in close proximity to the active site of deacetylase in the SIRT3 protein, and reduces the overall enzymatic efficiency of deacetylation. Furthermore, up-regulation of SIRT3 inhibited the cell growth of OSCCs and decreased the levels of basal reactive oxygen species (ROS) in both OSCC lines. To verify that the SIRT3 sequence variation was associated with oral carcinogenesis, we sequenced the SIRT3 gene from 21 OSCC patients, and 5 of the 21 patients (23.8%) carried the heterozygous missense mutation, p.Val208Ile. The heterozygous missense mutation in these patients was present in gremlin DNA isolated from both normal and tumor tissues.

CONCLUSIONS

Our findings provide a valuable insight into the potential role of SIRT3 in the development of oral squamous cell carcinoma, by showing that a non-synonymous point mutation in SIRT3 contributes to reduced catalytic activity of the protein and affects redox balance in OSCCs.

Abstract LB-5: A proteomic approach to study molecular mechanisms of andrographolide-mediated degradation of Src oncoproteins

Andrographolide is a lactone diterpenoid compound isolated from Andrographis paniculata. Accumulating studies have demonstrated the anticancer activity of andrographolide. Andrographolide treatment could induce apoptosis of cancer cells and inhibit multiple malignant cancer phenotypes, such as aberrant proliferation, angiogenesis and metastasis. It is widely demonstrated that cancer cells require oncogene(s) for survival and maintenance of malignant phenotypes, a phenomenon called oncogene addiction. Thus, targeting oncoprotein(s) has been considered as an effective strategy for cancer therapy. Elevated protein expression and activity of Src oncoproteins have strong associations with carcinogenesis. Previous data from our laboratory have shown that andrographolide treatment led to degradation of Src proteins, suppression of Src-mediated cellular transformation and apoptosis of Src-transformed cells (J Biol Chem 2008; 283: 5023-33). To further reveal the molecular basis of andrographolide-mediated Src degradation, a proteomic approach was carried out to identify proteins specifically regulated by andrographolide. Proteomes from v-Src expressing RK3E cells treated with vehicle, andrographolide and NCTU-048 (an inactive andrographolide analog) were compared using two-dimensional electrophoresis and proteins with differential expression pattern in andrographolide-treated cells were further identified using mass spectrometry. Among the identified proteins, an N-terminal fragment of Hsp90 protein was selectively elevated (2.5-fold) in andrographolide-treated cells. Src oncoproteins are known client proteins of Hsp90 and their stability are modulated by Hsp90. We therefore investigated whether Hsp90 cleavage is a crucial event in andrographolide-mediated degradation of Src oncoproteins. Using Western blot analysis, we confirmed that Hsp90 cleavage was induced in various types of Src-transformed cells under andrographolide treatment in a concentration- and time-dependent manner. Notably, the Src-repressing activity of andrographolide and its derivatives correlated well with their ability to induce Hsp90 cleavage. Moreover, the amount of cleaved Hsp90 fragment induced by andrographolide and its derivatives positively correlated with the status of transformation suppression and apoptosis caused by these compounds. Notably, the andrographolide-induced Hsp90 cleavage, Src degradation, cellular transformation and induction of apoptosis were restored by ROS inhibitor, N-acetyl-cysteine (NAC). The molecular basis of andrographolide-induced biological effects via ROS is currently under investigation.

Citation Format: Sheng-Hung Liu, Pei-Fen Chen, Chao-Hsiung Lin, Chung-Ming Sun, Chin-Wen Chi, Shu-Ling Fu. A proteomic approach to study molecular mechanisms of andrographolide-mediated degradation of Src oncoproteins. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr LB-5. doi:10.1158/1538-7445.AM2013-LB-5

Asymmetric effects of investor sentiment on industry stock returns: Panel data evidence

This article employs a state-of-the-art panel threshold model by allowing for regime intercepts, in order to shed new light on the asymmetric/nonlinear effects of local and global sentiments on expected industry stock returns among 11 Asian countries during the period from 1996 to 2010. Empirical evidence demonstrates that once the regime intercept is included, the asymmetric effects of global sentiment on oil & gas, financials, and health care industry returns become less under optimism, as compared with under pessimism. More critically, the positive (negative) impact of global sentiment above (under) the threshold turns significant, indicating that global optimism leads industry returns to be overvalued, while pessimism leads them to be undervalued. For local market sentiment, our results support that higher local sentiment enhances the returns of basic materials, telecommunications, and utilities industries. The empirical results confirm that the nexus of industry returns and investor sentiments is subject to change between different sentimental intervals.

4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone is correlated with 8-hydroxy-2'-deoxyguanosine in humans after exposure to environmental tobacco smoke

Cigarette smoking and exposure to environmental tobacco smoke (ETS) are important risk factors for many cancers. However, exposure doses have usually not been quantitatively assessed in human studies. In humans 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol and its glucuronate conjugate (defined as total NNAL) are the major metabolites of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone, a cigarette-specific carcinogen. Although animal studies have shown that exposure to cigarette smoke increases tissue oxidative DNA damage, the relationship between cigarette smoke and 8-hydroxydeoxyguanosine (8-OHdG) is not consistent in human studies. In the present study, we have developed a simple, sensitive, and robust LC-MS/MS method for quantifying total NNAL and 8-OHdG concentrations in human plasma. We quantified total NNAL and 8-OHdG in plasma as well as 8-OHdG in urine of 121 healthy male subjects. Total NNAL levels were significantly higher in ever-smokers than in never-smokers. Furthermore, total NNAL levels in plasma were increased with numbers of cigarettes smoked per day in ever-smokers. It suggests that total NNAL in plasma is a good biomarker for cigarette smoke exposure. After stratifying by smoking status and adjusting for age, ETS exposure and occupation category, total NNAL was associated with plasma and urinary 8-OHdG in never-smokers, but not in ever-smokers. Since total NNAL levels in nonsmokers represented the ETS exposure, it appears that 8-OHdG levels are dose-dependently correlated with their ETS exposure dose. Furthermore, this correlation supports the hypothesis that oxidative DNA damage is one of major adverse effects induced by ETS exposure in humans.

Relationship between cumulative dose of thiazolidinediones and clinical outcomes in type 2 diabetic patients with history of heart failure: a population-based cohort study in Taiwan

BACKGROUND

Thiazolidinediones (TZDs) are widely used antidiabetic agents, but there is great concern and conflicting reports over their possible effect on cardiovascular morbidity, especially in patients with heart failure (HF).

METHODS

Using 2000-2005 Taiwan's National Health Insurance (NHI) claims data, this population-based, retrospective cohort study investigated if there was an association between the cumulative TZD dose and clinical outcomes in type 2 diabetic patients recently hospitalized for HF. Study outcomes were death, first all-cause readmission, and first readmission for HF. Cox proportional hazard models were used to analyze the association between TZD versus sulfonylurea (SU) use and these outcomes.

RESULTS

Out of a total of 8139 eligible patients, 224 were taking TZD (65.63% female; mean [SD] age, 68.30[10.60] years) and 7915 were taking SU (55.10% female; 70.30[10.50] years). Patients taking TZD were at higher risk for readmission for HF (59 cases; HR 1.58 (95% confidence interval, 95%CI 1.44-1.72)), all-cause readmission (147 cases; 1.40 (1.30-1.70)), and death (103 cases; 2.23 (1.58-3.14)). The higher the cumulative exposure to TZD, the greater the risk of HF readmission, all-cause readmission, and death.

CONCLUSION

Among diabetic patients who had been hospitalized for HF, TZD users were at significantly greater risk for readmission for HF, all-cause readmission, and death than SU users. The risk of all adverse clinical outcomes appeared to highly relate to cumulative exposure to TZD. These findings provide empirical evidence supporting the latest black box warnings issued by the United States Food and Drug Administration in August, 2007 advising that TZD not be prescribed for diabetic patients with symptomatic heart failure.

Cardiovascular and gastrointestinal events of three antiplatelet therapies: clopidogrel, clopidogrel plus proton-pump inhibitors, and aspirin plus proton-pump inhibitors in patients with previous gastrointestinal bleeding

BACKGROUND

Concomitant use of antiplatelet agents and proton-pump inhibitors (PPIs) has been recommended in patients with a history of gastrointestinal (GI) hemorrhage. However, recent studies have reported that PPIs may alter clopidogrel's pharmacokinetics and potentially lead to an increased risk of recurrent adverse cardiovascular (CV) events.

METHODS

Using Taiwan's 2000-2006 National Health Insurance database, this population-based retrospective cohort study assessed CV and GI events in patients who had a prior history of GI bleeding and had been prescribed ongoing antiplatelet therapy after acute coronary syndrome (ACS) discharge. We identified 3,580 ACS patients and categorized them into (1) those taking clopidogrel alone, (2) those taking clopidogrel plus PPIs, and (3) those taking aspirin plus PPIs. Cox proportional hazards models were used to assess the association between the use of antiplatelet therapies and CV/GI events.

RESULTS

The clopidogrel only group and the clopidogrel plus PPI group were found to be at lower risk for GI events than the aspirin plus PPI group [adjusted hazard ratio (HR) 0.23 (95% confidence interval; CI 0.14-0.36) and HR 0.70 (0.52-0.96), respectively]. However, while the clopidogrel only group had a lower risk of CV events than the aspirin plus PPI group [HR 0.57 (0.38-0.84)], the clopidogrel plus PPI group had a significantly higher CV risk than the aspirin plus PPI group [HR 1.59 (1.18-2.13)].

CONCLUSIONS

Our findings suggest that although the use of clopidogrel plus PPIs provides GI benefits, with this treatment, there is an increased CV risk among patients with a history of GI bleeding.

The potentially inappropriate prescription of new drug: thiazolidinediones for patients with type II diabetes in Taiwan

PURPOSE

To examine the potentially inappropriate prescription of thiazolidinediones (TZD).

METHODS

Data on TZD prescriptions were collected from Taiwan's National Health Insurance dataset from 2001 to 2006. TZDs were considered inappropriately prescribed when they were prescribed to patients who were (1) under 18 years old, (2) pregnant, who had (3) type 1 diabetes, (4) severe heart failure, (5) hepatic insufficiency, or (6) renal insufficiency and taking TZD + metformin in combination. We aggregated potentially inappropriate prescriptions of TZD for each health-care institution in each month starting from March 2001, when TZD was introduced to Taiwan's market.

RESULTS

The potentially inappropriate prescription of TZD increased from 9.41% in 2001 to 12.50% in 2006. Prior inappropriate prescription led to a 0.06% (95%CI: 0.04-0.08) further increase in its later inappropriate prescription. Accumulated months of experience prescribing TZD was found associated with higher proportion of inappropriate prescription of TZD (0.03%, 95%CI: 0.01-0.05). However, it was negatively associated with new incidence of inappropriate prescription of TZD (-0.20, 95%CI: -0.22 to -0.18). The greater the volume of prior TZD prescription (-0.87%, 95%CI: -0.93 to -0.81) and the greater the number of accumulated months since adoption (-0.14%, 95%CI: -0.16 to -0.12), the greater the decrease in rates of new inappropriate prescriptions.

CONCLUSIONS

Along with the quick penetration of the new DM drug came an increased possibility that it would be prescribed inappropriately, a trend that persisted over time.

Leonurine improves ischemia-induced myocardial injury through antioxidative activity

The present study was designed to investigate the protective effects of 4-guanidino-n-butyl syringate (leonurine), a compound in Herba Leonuri (HL) on ischemic rat heart to determine the protective mechanisms associated with ischemic rat hearts. Rat heart ischemia was induced by ligation of the left coronary artery. Creatine kinase (CK) and lactate dehydrogenase (LDH) in plasma and superoxide dismutase (SOD) activity in heart homogenates were measured. We found leonurine significantly decreased levels of LDH and CK activities in plasma. This observation corresponded with decreased infarct size of ischemic rat heart induced by ligation of the left coronary artery. Moreover, the mRNA expression of the pro-apoptotic gene Bax was significantly down-regulated by 0.68-fold (p < 0.05) and the anti-apoptotic gene Bcl-2 was up-regulated by 1.41-fold (p < 0.05) in the leonurine treated groups as compared with acute myocardium ischemia (MI) controls measured by RT-PCR. Correspondingly, Bcl-2 and Bax protein levels detected by Western blotting coincided with gene expression levels. In addition, the mRNA expression level of the antioxidant enzyme Mn-SOD was significantly increased 1.23-fold (p < 0.05) and this finding corresponded with an observed increase in SOD activity and also with a committed decrease in lipid peroxidation. Taken together, our results demonstrated that leonurine attenuated myocardium injury during MI via antioxidative and anti-apoptotic effects and leonurine might become a useful adjuvant cardioprotective agent.

Pharmaceutical penetration of new drug and pharmaceutical market structure in Taiwan: hospital-level prescription of thiazolidinediones for diabetes

This study used Taiwan's National Health Insurance claim database (years 2000-2005) to examine how thiazolidinediones (TZD), a new class of drugs for diabetes, penetrated into Taiwan's hospitals, and its association with the concentration of all diabetes drugs at the hospital level. We collected 72 monthly summaries of diabetes prescriptions from all hospitals in Taiwan. Hospital-level pharmaceutical concentration was measured by penetration of TZD, defined as monthly market share of TZD in each hospital. Concentration of diabetes drugs was measured by Herfindahl-Hirschman indices. We found a negative association (coefficient = -0.3610) between TZD penetration and concentration of diabetes drug but a positive association between penetration of TZD and the volume of prescribed diabetes drugs (coefficient = 0.4088). In conclusion, hospital characteristics and volume of services determined the concentration of pharmaceuticals at the institution level, reflecting the heterogeneous competition between pharmaceutical companies within each hospital. Institution-level pharmaceutical concentration influences the adoption and penetration of new drugs.

ISO-1, a macrophage migration inhibitory factor antagonist, inhibits airway remodeling in a murine model of chronic asthma

Airway remodeling is the process of airway structural change that occurs in patients with asthma in response to persistent inflammation and leads to increasing disease severity. Drugs that decrease this persistent inflammation play a crucial role in managing asthma episodes. Mice sensitized (by intraperitoneal administration) and then challenged (by inhalation) with ovalbumin (OVA) develop an extensive eosinophilic inflammatory response, goblet cell hyperplasia, collagen deposition, airway smooth muscle thickening, and airway wall area increase, similar to pathologies observed in human asthma. We used OVA-sensitized/challenged mice as a murine model of chronic allergic airway inflammation with subepithelial fibrosis (i.e., asthma). In this OVA mouse model, mRNA and protein of macrophage migration inhibitory factor (MIF) are upregulated, a response similar to what has been observed in the pathogenesis of acute inflammation in human asthma. We hypothesized that MIF induces transforming growth factor-β1 (TGF-β1) synthesis, which has been shown to play an important role in asthma and airway remodeling. To explore the role of MIF in the development of airway remodeling, we evaluated the effects of an MIF small-molecule antagonist, (S,R)3-(4-hy-droxyphenyl)-4,5-dihydro-5-isoxazole acetic acid methyl ester (ISO-1), on pathologies associated with the airway-remodeling process in the OVA mouse model. We found that administration of ISO-1 significantly mitigated all symptoms caused by OVA treatment. In addition, the treatment of OVA-sensitized mice with the MIF antagonist ISO-1 significantly reduced TGF-β1 mRNA levels in pulmonary tissue and its protein level in bronchial alveolar lavage fluid supernatants. We believe the repression of MIF in the ISO-1 treatment group led to the significant suppression observed in the inflammatory responses associated with the allergen-induced lung inflammation and fibrosis in our murine asthma (OVA) model. Our results implicate a possible function of MIF in the pathogenesis of chronic asthma and suggest that MIF might be an important therapeutic target for airway remodeling.

[Effects of dexamethasone on intracellular expression of Th17 cytokine interleukin 17 in asthmatic mice]

OBJECTIVE

To study the effects of dexamethasone on intracellular expression of Th17 cytokine interleukin 17 and the mechanisms in asthmatic mice.

METHODS

Experimental asthma was induced by ovalbumin (OVA) sensitization in 20 in female Balb/c mice with (dexamethasone group, n=10) or without dexamethasone treatment (model group, n=10), with another 10 serving as the control group. The levels of IL-17 in the bronchoalveolar lavage fluid (BALF) and serum of the mice were measured by enzyme-linked immunosorbent assay (ELISA), and the airway inflammation was evaluated by HE staining. The expressions of IL-17 and RORgammat mRNA were measured by reverse transcription-polymerase chain reaction (RT-PCR), and the expression of RORgammat protein was measured by immunohistochemical staining.

RESULTS

The levels of RORgammat and IL-17 mRNA and protein in the asthmatic model group were significantly higher than those in the control group (P<0.01), and the increased expressions of RORgammat and IL-17 mRNA and protein in the asthmatic mice were significantly reduced by dexamethasone treatment (P<0.05).

CONCLUSION

Dexamethasone can inhibit the release of IL-17 probably by inhibiting RORgammat expression and blocking Th17 differentiation in asthmatic mice.

The relationship between influenza vaccination and outpatient visits for upper respiratory infection by the elderly in Taiwan

OBJECTIVE

To evaluate the effect of influenza vaccination on the reduction of the risk of outpatient visits for upper respiratory infection (URI) among the elderly in Taiwan.

METHODS

The data for this observational study, consisting of 1729 people aged 65 years or older, were drawn from Taiwan's 2001 National Health Interview Survey. This survey data was then linked with National Health Insurance claim data for December 2001 to November 2002. Survival analysis of Cox proportional hazards model was performed to examine the risk of URI outpatient visits in elderly people vaccinated with the influenza vaccine and those not vaccinated during a year-long study period since the influenza season began. To adjust for potential self-selection bias, we used propensity score method to categorize individuals into two groups, based on the predicted probability of being vaccinated from a logistic regression of spatial random effect. Propensity score group 1 (PSG 1) were those with a predicted probability of being vaccinated lower than 0.5, and PSG 2 were those with a predicted probability of being vaccinated of 0.5 or higher.

RESULTS

The overall vaccination rate was 50%. Logistic regression showed the probability of being vaccinated was related to the number of outpatient visits for URI before the influenza season began (odds ratio (OR) 1.07; 95% confidence interval (CI) 1.04-1.10). Our first survival analysis showed that being vaccinated significantly reduced the risk of URI outpatient visits in PSG 2 during the 1-year study period (hazard ratio 0.89; 95% CI 0.81-0.97). Separate survival analysis showed that being vaccinated reduced the risk of URI outpatient visits for both PSG groups during the first 3 months of the study period.

CONCLUSION

Being vaccinated could reduce the risk of outpatient visits for URI among the elderly during the influenza season.

The effect of changing reimbursement policies on quality of in-patient care, from fee-for-service to prospective payment

OBJECTIVE

Using insurance claims for hemorrhoidectomies, we examined the effect of Taiwan's Bureau of National Health Insurance's case payment system, a fixed case payment rate method used to reimburse health care providers for in-patient care.

DESIGN

This observational natural experimental study examined changes in medical care that occurred between two phases: the 9 months before case payment system was implemented on 1 October 1997 and the 9 months afterwards. The changes were analyzed by performing linear regressions with interaction between hospital type and the implementation of case payment system.

SETTING

This study was based on total claim data from National Health Insurance.

STUDY PARTICIPANTS

A total of 23 638 hemorrhoidectomy insurance claims.

MAIN OUTCOME MEASURES

Length of stay, number of medical services, and number of drug prescriptions. Medical services were stratified into those that were considered minimal requirements and those considered optional by the Bureau of National Health Insurance.

RESULTS

Over the 18-month period, the number of patients increased by 23.7%. After the case payment system was implemented, length of stay decreased by 0.59 days (P < 0.0001), the number of minimally required services increased by 2.19 to 4.24 items (P < 0.0001), the number of optional service items decreased by 0.32 items (P < 0.0001), and drug prescription decreased slightly by 0.58 to 0.99 items (P < 0.0001) per hospitalization.

CONCLUSIONS

The case payment system successfully shortened length of stay without significantly sacrificing the provision of services.

The effect of Taiwan's tax-induced increases in cigarette prices on brand-switching and the consumption of cigarettes

The effect of raising cigarette taxes to reduce smoking has been the subject of several studies, which often treat the price of cigarettes as an exogenous factor given to smokers who respond to it by adjusting their smoking behavior. However, cigarette prices vary with brand and quality, and smokers can and do switch to lower-priced brands to reduce the impact of the tax on the cost of cigarettes as they try to consume the same number of cigarettes as they had before a tax hike. Using data from a two-year follow-up interview survey conducted before and after a new cigarette tax scheme was imposed in Taiwan in 2002, this study examines three behavioral changes smokers may make to respond to tax-induced cigarette price increase: brand-switching, amount consumed, and amount spent on smoking. These changes were studied in relation to smoker income, before-tax cigarette price, level of addiction, exposure to advertizing, and consumer loyalty. We found that smokers, depending upon exposure to advertizing, level of consumer loyalty and initial price of cigarettes, switched brands to maintain current smoking habits and control costs. We also found that the initial amount smoked and level of addiction, not price, at least not at the current levels in Taiwan, determined whether a smoker reduced the number of cigarettes he consumed.

Signals in the activation of opioid mu-receptors by loperamide to enhance glucose uptake into cultured C2C12 cells

In an attempt to understand the signal pathways of opioid mu-receptors for glucose metabolism, we used loperamide to investigate the glucose uptake into the myoblast C2C12 cells. Loperamide enhanced the uptake of radioactive deoxyglucose into C2C12 cells in a concentration-dependent manner that was abolished in cells pre-incubated with naloxone or naloxonazine at concentrations sufficient to block opioid mu-receptors. Pharmacological inhibition of phospholipase C (PLC) by U73122 resulted in a concentration-dependent decrease in loperamide-stimulated uptake of radioactive deoxyglucose into C2C12 cells. This inhibition of glucose uptake by U73122 was specific since the inactive congener, U73343, failed to modify loperamide-stimulated glucose uptake. Moreover, both chelerythrine and GF 109203X diminished the action of loperamide at concentrations sufficient to inhibit protein kinase C (PKC). The obtained data suggest that an activation of opioid mu-receptors in C2C12 cells by loperamide may increase glucose uptake via the PLC-PKC pathway.

Public opinion regarding earmarked cigarette tax in Taiwan

BACKGROUND

Cigarette taxation has been perceived by academics and policy-makers as one of the most effective ways of reducing the use of cigarettes. On January 1 2002, the Taiwan government imposed a New Taiwan (NT) 5 dollars per pack tax earmarked for the purpose of tobacco control. This study uses a survey collected prior to taxation to assess public attitudes toward cigarette taxation, public beliefs about the effectiveness of cigarette taxation at reducing cigarette use and public opinions about the allocation of this tax revenue.

METHODS

Data were drawn from a national face-to-face interview on cigarette consumption in 2000. A total of 3,279 adults were aged 18 to 64 years; 49.9% of whom were male and 50.1% female, and with a smoking prevalence of 49.1% and 4.1%, respectively. The attitudes toward cigarette tax were analysed using multi-logit regressions. We analysed by logistic regression the potential changes in smoking behaviour that smokers might make in response to the five NT (New Taiwan) dollar earmarked tax on cigarettes per pack. We summarized public opinions about the allocation of earmarked tax revenue using descriptive statistics.

RESULTS

Current smokers (OR = 0.34) and former smokers (OR = 0.68) were less likely to support the cigarette tax than non-smokers. A favourable attitude toward the tax was positively associated with personal monthly income, especially among females. Among male smokers, the possibility of reducing/quitting smoking in response to the five-NT-dollar tax was negatively associated with the monthly expense for smoking. The two most frequently-suggested areas to receive money from the revenue collected from the earmarked tax were health education and cancer subsidy.

CONCLUSIONS

Smoking status and economic factors determine the attitude and potential responses of people toward the cigarette tax. Taiwan's five NT-dollar earmarked tax for cigarettes may have only a limited effect upon the reduction in cigarette use.

The clinical diagnosis of chronic acalculous cholecystitis

BACKGROUND

Chronic acalculous cholecystitis (CAC), a diagnosis of exclusion, appears to be more common than was previously thought. We correlated the pathology with test results and response to treatment in a prospective study to obtain data for evidence-based management.

METHODS

The study subjects were patients with chronic biliary symptoms but had normal sonogram results. They were further investigated with esophagogastroduodenoscopy, multidiscipline evaluations, and cholecystokinin-stimulated scintigraphy (CCK-HIDA). They were offered laparoscopic cholecystectomy (LC) when the symptoms were intransigent, and the main abnormality was a low ejection fraction (EF) as determined by CCK-HIDA. We analyzed the histologic findings of the gallbladder, CCK-HIDA EF, and clinical outcomes during the control period with a concurrent series of LC for calculus from the same surgeons.

RESULTS

Of 176 cholecystectomies for biliary pain without stones, 152 had pathologically verified CAC. EF by CCK-HIDA was low in patients with CAC (18%) and low in normal gallbladders (26%). In the same period, 497 patients had cholecystectomies for cholelithiasis. Lasting symptom relief for CAC after LC was not different from that for calculous disease (85% vs 90%).

CONCLUSIONS

The syndrome consisting of chronic biliary symptoms, stone-free sonograms, low EF in CCK-HIDA, and absence of other pain sources is highly predictive for CAC, which is well treated with LC, with results similar to those for calculous disease.

Complete genome analysis of enterovirus 71 isolated from an outbreak in Taiwan and rapid identification of enterovirus 71 and coxsackievirus A16 by RT-PCR

Hand, foot, and mouth disease (HFMD) and encephalomyelitis were two major clinical manifestations during the 1998 enterovirus 71 (EV71) epidemic in Taiwan. To investigate whether different clinical patterns were caused by alterations in EV71 genomes, the complete nucleotide sequences of four EV71 strains associated with HFMD or encephalomyelitis were compared. Among these viral strains, two or three nucleotide differences were found within the 5'-noncoding region, and two or four amino acid differences were found within the regions encoding viral polyproteins; however, none of these differences were correlated with either clinical manifestation. Because coxsackievirus A16 was another major causative agent of HFMD, a reverse transcription-polymerase chain reaction assay, with high sensitivity and specificity for identification of EV71 (both 100%) and coxsackievirus A16 (100 and 98.8%), was developed for the rapid differential identification of these two viruses in HFMD patients.

In vitro modified release of acyclovir from ethyl cellulose microspheres

The aim of this study was to demonstrate a sustained-release microparticulate dosage form for acyclovir via an in vitro study. Ethyl cellulose was selected as a model encapsulation material. All of the microspheres were prepared by an oil-in-water solvent evaporation technique. A 2(3) full factorial experiment was applied to study the effects of the viscosity of polymer, polymer/drug ratio, and polymer concentration on the drug encapsulation efficiency and the dissolution characteristics. The encapsulation efficiency of acyclovir in microspheres was in the range of 20.0-56.6%. Increase in the viscosity of ethyl cellulose and the ratio of CH2Cl2/ethyl cellulose increased drug encapsulation efficiency. The drug continuously released from microspheres for at least 12 h, and the release rate depended on the pH of the release medium. The sustained release characteristic was more prominent in the simulated intestine fluid than in the simulated gastric fluid. A faster release of drug was observed when a high viscosity polymer was used. The decomposition of acyclovir significantly decreased when encapsulated by ethyl cellulose, especially when stored at 37 and 50 degrees C.

Antibacterial activity of leaf essential oils and their constituents from Cinnamomum osmophloeum

The antibacterial activities of the essential oils from leaves of two Cinnamomum osmophloeum clones (A and B) and their chemical constituents were investigated in this study. The nine strains of bacteria, including Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Staphylococcus aureus, Staphylococcus epidermidis, methicillin-resistant Staphylococcus aureus (MRSA), Klebsiella pneumoniae, Salmonella sp., and Vibrio parahemolyticus, were used in the antibacterial tests. Results from the antibacterial tests demonstrated that the indigenous cinnamon B leaf essential oils had an excellent inhibitory effect. The MICs (minimum inhibitory concentrations) of the B leaf oil were 500 microg/ml against both K. pneumoniae and Salmonella sp. and 250 microg/ml against the other seven strains of bacteria. Cinnamaldehyde possessed the strongest antibacterial activity compared to the other constituents of the essential oils. The MICs of cinnamaldehyde against the E. coli, P. aeruginosa, E. faecalis, S. aureus, S. epidermidis, MRSA, K. pneumoniae, Salmonella sp., and V. parahemolyticus were 500, 1000, 250, 250, 250, 250, 1000, 500, and 250 microg/ml, respectively. These results suggest that C. osmophloeum leaf essential oil and cinnamaldehyde are beneficial to human health, having the potential to be used for medical purposes and to be utilized as anti-bacterial additives in making paper products.

Acute angle-closure glaucoma resulting from spontaneous hemorrhagic retinal detachment in age-related macular degeneration: case reports and literature review

PURPOSE

Acute angle-closure glaucoma resulting from massive subretinal hemorrhage is a rare and catastrophic complication in age-related macular degeneration. Anticoagulant usage had been strongly correlated with this complication in previously reported cases.

METHODS

Four patients (4 eyes), 3 men and 1 woman, developed angle-closure glaucoma with diffuse subretinal hemorrhage and total hemorrhagic retinal detachment.

RESULTS

Serial funduscopic examinations and echographic studies in 2 eyes showed that the blood gradually accumulated in the subretinal space. It took more than 10 days for the bleeding to build up to bullous hemorrhagic retinal detachment and secondary glaucoma. Anti-glaucomatous agents were given and sclerotomy was performed in 3 of the 4 patients. Phthisical changes were observed subsequently in these 3 eyes. The eye that received early drainage of blood was an exception, and a small degree of residual acuity was retained. Three of the 4 patients had diabetes mellitus, and hypertension and vascular diseases were also present in the same 3 patients.

CONCLUSIONS

Diabetes mellitus might be a predisposing factor for the impaired hemostasis. Anti-glaucomatous agents were of no effect in the management of intraocular pressure. Sclerotomy and drainage of blood help control intraocular pressure and relieve ocular pain. Poor final visual acuity is inevitable. However, phthisical changes might be prevented with early sclerotomy and drainage of blood.

Altered expression of nuclear matrix proteins in etoposide induced apoptosis in HL-60 cells

The events of cell death and the expression of nuclear matrix protein (NMP) have been investigated in a promyelocytic leukemic cell line HL-60 induced with etoposide. By means of TUNEL assay, the nuclei displayed a characteristic morphology change, and the amount of apoptotic cells increased early and reached maximun about 39% after treatment with etoposide for 2 h. Nucleosomal DNA fragmentation was observed after treatment for 4 h. The morphological change of HL-60 cells, thus, occurred earlier than the appearance of DNA ladder. Total nuclear matrix proteins were analyzed by 2-dimensional gel electrophoresis. Differential expression of 59 nuclear matrix proteins was found in 4 h etoposide treated cells. Western blotting was then performed on three nuclear matrix acssociated proteins, PML, HSC70 and NuMA. The expression of the suppressor PML protein and heat shock protein HSC70 were significantly upregulated after etoposide treatment, while NuMA, a nuclear mitotic apparatus protein, was down regulated. These results demonstrate that significant biochemical alterations in nuclear matrix proteins take place during the apoptotic process.

Antimite activity of essential oils and their constituents from Taiwania cryptomerioides

Antimite activity of essential oils and their components obtained from Taiwania cryptomerioides Hayata heartwood against Dermatophagoides pteronyssinus (Trouessart) and Dermatophagoides farinae Hughes was investigated in this study. Results from antimite tests demonstrated that the essential oil extracted from T. cryptomerioides heartwood had miticidal activity against D. pteronyssinus and D. farinae with a mortality of 67.0 and 36.7% at the dosage of 12.6 microg/cm2 after 48 h. Alpha-cadinol possessed the strongest antimite activity compared with other components of the T. cryptomeioides heartwood essential oil. The rectified mortalities of D. pteronyssinus and D. farinae were 100% for alpha-cadinol at the dosage of 6.3 microg/cm2. The order of antimite activity of four dominant constituents was alpha-cadinol > T-muurolol > ferruginol > T-cadinol. Paired Student's t-tests showed that there were significant differences between the rectified mortality of alpha-cadinol, T-muurolol, ferruginol and that of T-cadinol at the dosage of 6.3 microg/cm2 after 48 h.

An outbreak of enterovirus 71 infection in Taiwan, 1998. II. Laboratory diagnosis and genetic analysis

BACKGROUND

An epidemic of enterovirus 71 (EV71) occurred in Taiwan from April to December of 1998, with two peaks, one in June and the other in October. Many enteroviruses were isolated in our laboratory from 258 cases during this outbreak. Approximately half of the enteroviruses isolated were EV71 and one fifth were coxsackievirus A16.

OBJECTIVES

To analyze laboratory findings in the EV71 epidemic of 1998 in Taiwan, various EV71 specimens in different cell lines were examined. In addition, genetic analysis of 5' non-coding region (NCR) was performed to analyze the strain variation in this outbreak.

RESULTS

The cytopathic effect induced by EV71 was observed 2-13 (mean of 4.5) days post-inoculation in Vero cells and 4-15 (mean of 6.6) days in green monkey kidney (GMK) cells inoculated with throat swabs. Of the total positive EV71 cases, virus was most frequently obtained from throat swabs (91.7%), less from stools (64.8%), and none from cerebral spinal fluid (CSF). Molecular analyses of EV71 by sequencing the 5' NCR of 34 strains obtained from different clinical categories and various geographic areas showed that their sequences differed (0-13 bp in 681 bp sequenced) by approximately 0-2%. The sequences of these isolates differed from EV71 prototype BrCr or MS strain by 17.5-19%, with the exception of two samples which exhibited nucleotide variation by only 8.9 and 8.2%, when compared to the MS strain.

CONCLUSION

EV71 was most frequently isolated from throat swab specimens in Vero cells. The molecular analyses of the 5' NCR of EV71 revealed that most isolates from this epidemic belonged to a group of closely related clones and only two were in a different group which was clustered with the EV71 MS strain.

Characterization of the roles of the 594-645 region in human endothelial nitric-oxide synthase in regulating calmodulin binding and electron transfer

It has been postulated that a segment (residues 594-645) inserted in the FMN subdomain of human endothelial nitric-oxide synthase (eNOS) plays a crucial role in controlling Ca(2+)-dependent CaM binding for eNOS activity. To investigate its functions, we expressed human eNOS in a baculovirus system with deletion of a 45-residue segment from this region (residues 594-606 and 614-645, designated as Delta45eNOS), and characterized the purified mutant enzyme. In contrast with wild-type eNOS, Delta45eNOS exhibited characteristics resembling inducible NOS (iNOS). It contained an endogenously bound CaM, which was essential in folding and stabilizing this mutant enzyme, and retained 60% of L-citrulline formation in 5 mM EGTA. We also produced four N-terminally truncated reductase domains with or without the 45-residue segment, and either including or excluding the CaM-binding sequence. Basal cytochrome c reductase activity of reductase domains without the 45-residue segment was up to 20 fold greater than that of corresponding insert-containing domains, and higher than CaM-stimulated activity of the wild-type enzyme. A series of mutants with smaller fragment deletion in this region such as Delta594-604, Delta605-612, Delta613-625, Delta626-634, Delta632-639, and Delta640-645 mutants were further characterized. The crude lysate of mutants Delta613-625 and Delta632-639 did not show activity in the presence of Ca(2+)/CaM, while other four mutants had activity comparable to that of WTeNOS. The purified Delta594-604 and Delta605-612 proteins had a 3-5-fold higher affinity for Ca(2+)/CaM, but their L-citrulline forming activity was still 80% dependent upon the addition of Ca(2+)/CaM. Both mutants exhibited a low level of the cytochrome c and ferricyanide reductase activities, which either did not respond to (Delta594-604) or slightly enhanced by (Delta605-612) the exogenous CaM. In contrast, activities of Delta626-634 and Delta640-645 like those of WTeNOS were largely Ca(2+)/CaM-dependent. Thus, our findings indicate that the N-terminal half of the 594-645 segment containing residues 594-612 plays a significant role in regulating Ca(2+)/CaM binding.