Surface Electromyography for Evaluating the Effect of Aging on the Coordination of Swallowing Muscles

Swallowing function can deteriorate with age, leading to a risk of dysphagia. Swallowing evaluation by surface electromyography (sEMG) can be easily and extensively applied for an elderly population. This study evaluated the temporal events observed by sEMG to clarify how aging affects the coordination among the masticatory and suprahyoid muscles. We recruited elderly individuals (over 65 years old) who denied dysphagia. The sEMG activities of anterior temporalis, masseter, and suprahyoid muscles were recorded during 3, 15, and 30 ml water swallowing tests (WST). We calculated the time interval between anterior temporalis and suprahyoid peak activity (T-SH interval) and masseter and suprahyoid peak activity (M-SH interval) and analyzed their correlation with age. The subjects who could and could not swallow 30 ml of water in one gulp were further assigned into the one-gulp and piecemeal groups, respectively, for subgroup analysis. We recruited 101 subjects, among whom 75 (26 males and 49 females) were analyzed after excluding those with suspected dysphagia or low-quality sEMG recordings. Age was significantly correlated with the bilateral T-SH (left: r = 0.249, p = 0.031; right: r = 0.412, p < 0.01) and right M-SH (r = 0.242, p = 0.037) intervals in the 30 ml WST. The correlation between intervals and age were observed in both subgroups. sEMG can be used to investigate the effect of aging on the temporal coordination between masticatory and suprahyoid contraction. Further studies are needed to verify the validity of screening subclinical dysphagia in the elderly.

Evaluation of risk adjustment performance of diagnosis-based and medication-based comorbidity indices in patients with chronic obstructive pulmonary disease

Objectives

This study assessed risk adjustment performance of six comorbidity indices in two categories of comorbidity measures: diagnosis-based comorbidity indices and medication-based ones in patients with chronic obstructive pulmonary disease (COPD).

Methods

This was a population–based retrospective cohort study. Data used in this study were sourced from the Taiwan National Health Insurance Research Database. The study population comprised all patients who were hospitalized due to COPD for the first time in the target year of 2012. Each qualified patient was individually followed for one year starting from the index date to assess two outcomes of interest, medical expenditures within one year after discharge and in-hospital mortality of patients. To assess how well the added comorbidity measures would improve the fitted model, we calculated the log-likelihood ratio statistic G2. Subsequently, we compared risk adjustment performance of the comorbidity indices by using the Harrell c-statistic measure derived from multiple logistic regression models.

Results

Analytical results demonstrated that that comorbidity measures were significant predictors of medical expenditures and mortality of COPD patients. Specifically, in the category of diagnosis-based comorbidity indices the Elixhauser index was superior to other indices, while the RxRisk-V index was a stronger predictor in the framework of medication-based codes, for gauging both medical expenditures and in-hospital mortality by utilizing information from the index hospitalization only as well as the index and prior hospitalizations.

Conclusions

In conclusion, this work has ascertained that comorbidity indices are significant predictors of medical expenditures and mortality of COPD patients. Based on the study findings, we propose that when designing the payment schemes for patients with chronic diseases, the health authority should make adjustments in accordance with the burden of health care caused by comorbid conditions.

Exploiting deep neural network and long short-term memory method-ologies in bioacoustic classification of LPC-based features

The research describes the recognition and classification of the acoustic characteristics of amphibians using deep learning of deep neural network (DNN) and long short-term memory (LSTM) for biological applications. First, original data is collected from 32 species of frogs and 3 species of toads commonly found in Taiwan. Secondly, two digital filtering algorithms, linear predictive coding (LPC) and Mel-frequency cepstral coefficient (MFCC), are respectively used to collect amphibian bioacoustic features and construct the datasets. In addition, principal component analysis (PCA) algorithm is applied to achieve dimensional reduction of the training model datasets. Next, the classification of amphibian bioacoustic features is accomplished through the use of DNN and LSTM. The Pytorch platform with a GPU processor (NVIDIA GeForce GTX 1050 Ti) realizes the calculation and recognition of the acoustic feature classification results. Based on above-mentioned two algorithms, the sound feature datasets are classified and effectively summarized in several classification result tables and graphs for presentation. The results of the classification experiment of the different features of bioacoustics are verified and discussed in detail. This research seeks to extract the optimal combination of the best recognition and classification algorithms in all experimental processes.

Strong horizontal and vertical connectivity in the coral Pocillopora verrucosa from Ludao, Taiwan, a small oceanic island

Mesophotic habitats could be sheltered from natural and anthropogenic disturbances and act as reproductive refuges, providing propagules to replenish shallower populations. Molecular markers can be used as proxies evaluating the connectivity and inferring population structure and larval dispersal. This study characterizes population structure as well as horizontal and vertical genetic connectivity of the broadcasting coral Pocillopora verrucosa from Ludao, a small oceanic island off the eastern coast of Taiwan. We genotyped 75 P. verrucosa specimens from three sites (Gongguan, Dabaisha, and Guiwan) at three depth ranges (Shallow: 7-15 m, Mid-depth: 23-30 m, and Deep: 38-45 m), spanning shallow to upper mesophotic coral reefs, with eight microsatellite markers. F-statistics showed a moderate differentiation (FST = 0.106, p<0.05) between two adjacent locations (Dabaisha 23-30 and Dabaisha 38-45 m), but no differentiation elsewhere, suggesting high levels of connectivity among sites and depths. STRUCTURE analysis showed no genetic clustering among sites or depths, indicating that all Pocillopora individuals could be drawn from a single panmictic population. Simulations of recent migration assigned 30 individuals (40%) to a different location from where they were collected. Among them, 1/3 were assigned to deeper locations, 1/3 to shallower populations and 1/3 were assigned to the right depth but a different site. These results suggest high levels of vertical and horizontal connectivity, which could enhance the recovery of P. verrucosa following disturbances around Ludao, a feature that agrees with demographic studies portraying this species as an opportunistic scleractinian.

The effectiveness of simulation education program on shared decision-making attitudes among nurses in Taiwan

Background

Shared decision-making (SDM) is significantly associated with promoting the quality of end-of-life (EOL). The attitude of nurses toward the end of life can affect EOL care, but there are few SDM-related clinical learning programs focused on EOL. In this study, therefore, we evaluated the effectiveness of an EOL-simulation education program on attitudes toward SDM among nurses, using an objective structured clinical examination (OSCE).

Methods

We used a quasi-experimental study design to evaluate nurses working at a medical center in Taiwan. We recruited 100 nurses and assigned them to an experimental group (n = 50) and a control group (n = 50). The experimental group received the SDM attitude (SDMA) cultivation program, and the control group did not. After the intervention, all participants were examined in an OSCE to assess the efficacy of their learning. A p value of.05 was considered statistically significant.

Results

The average score of the experimental group was higher than that of the control group in the dimensions “empathic communication” and “mastery learning”, but these differences were not significant. SDMA score is significantly and positively correlated with SDMA global score, standardized patient survey (SPS) score, and SPS global score (r = .92, .56, and .50, respectively; p < .01).

Conclusions

Simulations concerning EOL care that incorporate SDM components would be effective for training clinical nurses. This study can serve as a reference for nursing-administration managers who may consider designing SDM-related education programs to improve the quality of clinical nursing care.

Snail regulation in fibroblast-like synoviocytes by a histone deacetylase or glycogen synthase kinase inhibitor affects cell proliferation and gene expression

BACKGROUND

Snail has been linked to the pathogenesis of rheumatoid arthritis (RA). We plan to investigate the regulation of Snail in response to TNF-α, histone acetylation, and glycogen synthase kinase-3 (GSK)-3 inhibition in fibroblast-like synoviocytes (FLSs).

METHODS

FLSs from rats with collagen-induced arthritis (CIA) were collected and treated with TNF-α alone or a combination with trichostatin A (TSA), a pan-histone deacetylase inhibitor and lithium chloride (LiCl), a glycogen synthase kinase-3 (GSK)-3 inhibitor.

RESULTS

We demonstrated for the first time that nuclear expression of Snail in FLSs from rats with CIA was correlated with the levels of extracellular TNF-α and acetylation status. Cell proliferation and viability of CIA FLSs were reduced in response to TSA treatment and short-hairpin RNA specific to Snail. LiCl treatment increased Snail and cadherin-11 (Cad-11) expression in CIA FLSs.

CONCLUSION

We suggested from this study that targeting TNF-α-histone deacetylase-Snail signaling axis or the Wnt signaling pathway in FLSs might provide therapeutic interventions for the treatment of RA in the future.

Investigation of dual antiplatelet therapy after coronary stenting in patients with chronic kidney disease

Background

Dual antiplatelet therapy (DAPT) is currently the standard treatment for the prevention of ischemic events after stent implantation. However, the optimal DAPT duration remains elusive for patients with chronic kidney disease (CKD). Therefore, we aimed to compare the effectiveness and safety between long-term and short-term DAPT after coronary stenting in patients with CKD.

Methods

This retrospective cohort study analyze data from the Taipei Medical University (TMU) Institutional and Clinical Database, which include anonymized electronic health data of 3 million patients that visited TMU Hospital, Wan Fang Hospital, and Shuang Ho Hospital. We enrolled patients with CKD after coronary stenting between 2008 and 2019. The patients were divided into the long-term (>6 months) and short-term DAPT group (≤ 6 months). The primary end point was major adverse cardiovascular events (MACE) from 6 months after the index date. The secondary outcomes were all-cause mortality and Thrombolysis in Myocardial Infarction (TIMI) bleeding.

Results

A total of 1899 patients were enrolled; of them, 1112 and 787 were assigned to the long-term and short-term DAPT groups, respectively. Long-term DAPT was associated with similar risk of MACE (HR: 1.05, 95% CI: 0.65–1.70, P = 0.83) compare with short-term DAPT. Different CKD risk did not modify the risk of MACE. There was also no significant difference in all-cause mortality (HR: 1.10, 95% CI: 0.75–1.61, P = 0.63) and TIMI bleeding (HR 1.19, 95% CI: 0.86–1.63, P = 0.30) between groups.

Conclusions

Among patients with CKD and coronary stenting, we found that long-term and short-term DAPT tied on the risk of MACE, all-cause mortality and TIMI bleeding.

Prevalence and psychosocial risk factors of nonsuicidal self-injury among adolescents during the COVID-19 outbreak

The research investigated the prevalence of nonsuicidal self-injury (NSSI) during the COVID-19 outbreak and identified the psychosocial risk factors among junior high school students in Taiwan. Cross-sectional design was applied and 1,060 participants (Mage = 14.66, SD = 0.86 years) were recruited into the study. The prevalence of NSSI was found to be 40.9% (95% confidence interval, 37.9%-43.9%) during the COVID-19 outbreak. The results suggested that the self-injurers group were mostly female, and scored significantly higher in neuroticism, depression, impulsivity, alexithymia, virtual social support, dissatisfaction with academic performance, and lower in subjective wellbeing, self-esteem, actual social support, and family function than the non-injurers group. In addition, high neuroticism, low self-esteem, high virtual social support, high impulsivity, and high alexithymia were independently predictive in the logistic regression analysis. The principal results of this study suggested that NSSI was extremely prevalent among adolescents during the COVID-19 outbreak, and in particularly, personality and virtual environment risk factors and enhancing self-esteem should be the focus of NSSI preventive strategies when targeting this age population. Our results provide a reference towards designing NSSI prevention programs geared toward the high school population during the COVID-19 pandemic.

Antibody Watch: Text mining antibody specificity from the literature

Antibodies are widely used reagents to test for expression of proteins and other antigens. However, they might not always reliably produce results when they do not specifically bind to the target proteins that their providers designed them for, leading to unreliable research results. While many proposals have been developed to deal with the problem of antibody specificity, it is still challenging to cover the millions of antibodies that are available to researchers. In this study, we investigate the feasibility of automatically generating alerts to users of problematic antibodies by extracting statements about antibody specificity reported in the literature. The extracted alerts can be used to construct an “Antibody Watch” knowledge base containing supporting statements of problematic antibodies. We developed a deep neural network system and tested its performance with a corpus of more than two thousand articles that reported uses of antibodies. We divided the problem into two tasks. Given an input article, the first task is to identify snippets about antibody specificity and classify if the snippets report that any antibody exhibits non-specificity, and thus is problematic. The second task is to link each of these snippets to one or more antibodies mentioned in the snippet. The experimental evaluation shows that our system can accurately perform the classification task with 0.925 weighted F1-score, linking with 0.962 accuracy, and 0.914 weighted F1 when combined to complete the joint task. We leveraged Research Resource Identifiers (RRID) to precisely identify antibodies linked to the extracted specificity snippets. The result shows that it is feasible to construct a reliable knowledge base about problematic antibodies by text mining.

Antibodies are widely used reagents to test for the expression of proteins. However, antibodies are also a known source of reproducibility problems in biomedicine, as specificity and other issues can complicate their use. Information about how antibodies perform for specific applications are scattered across the biomedical literature and multiple websites. To alert scientists with reported antibody issues, we develop text mining algorithms that can identify specificity issues reported in the literature. We developed a deep neural network algorithm and performed a feasibility study on 2,223 papers. We leveraged Research Resource Identifiers (RRIDs), unique identifiers for antibodies and other biomedical resources, to match extracted specificity issues with particular antibodies. The results show that our system, called “Antibody Watch,” can accurately perform specificity issue identification and RRID association with a weighted F-score over 0.914. From our test corpus, we identified 37 antibodies with 68 nonspecific issue statements. With Antibody Watch, for example, if one were looking for an antibody targeting beta-Amyloid 1–16, from 74 antibodies at dkNET Resource Reports (on 10/2/20), one would be alerted that “some non-specific bands were detected at 55 kDa in both WT and APP/PS1 mice with the 6E10 antibody…”

Early blood pH as an independent predictor of neurological outcome in patients with out-of-hospital cardiac arrest: A retrospective observational study

ABSTRACT

Metabolic acidosis is observed in 98% of patients with out-of-hospital cardiac arrest (OHCA). The longer the no-flow or low-flow duration, the more severe is the acidosis in these patients. This study explored whether blood pH in early stages of advanced life support (ALS) was an independent predictor of neurological prognosis in patients with OHCA.We retrospectively enrolled patients with OHCA from January 2012 to June 2018 in a single-medical tertiary hospital in Taiwan. Patients with OHCA whose blood gas analyses within 5 minutes after receiving ALS at the emergency department (ED) were enrolled. Patients younger than 20 years old, with cardiac arrest resulting from traumatic or circumstantial causes, with return of spontaneous circulation (ROSC) before ED arrival, lacking record of initial blood gas analysis, and with do-not-resuscitate orders were excluded. The primary outcome of this study was neurological status at hospital discharge.In total, 2034 patients with OHCA were enrolled. The majority were male (61.89%), and the average age was 67.8 ± 17.0 years. Witnessed OHCA was noted in 571 cases, cardiopulmonary resuscitation was performed before paramedic arrival in 512 (25.2%) cases, and a shockable rhythm was observed in 269 (13.2%). Blood pH from initial blood gas analysis remained an independent predictor of neurological outcome after multivariate regression.Blood pH at early stages of ALS was an independent prognostic factor of post-OHCA neurological outcome. Blood gas analysis on arrival at the ED may provide additional information about the prognosis of patients with OHCA.

Silicon-containing water intake confers antioxidant effect, gastrointestinal protection, and gut microbiota modulation in the rodents

We explored the effects of silicon-containing water (BT) intake on gastrointestinal function and gut microbiota. BT was obtained by pressuring tap water through silicon minerals (mullite, Al₆Si₂O₁₃) column. BT decreased H₂O₂ chemiluminescence counts, indicating its antioxidant activity. Four weeks of BT drinking increased H₂O₂ scavenging activity and glutathione peroxidase activity of plasma. BT drinking did not affect the body weight but significantly reduced the weight of feces and gastrointestinal motility. BT drinking significantly suppressed pylorus ligation enhanced gastric juice secretion, gastric reactive oxygen species amount, erythrocyte extravasation, IL-1β production by infiltrating leukocyte, and lipid peroxidation within gastric mucosa. Data from 16S rRNA sequencing revealed BT drinking significantly increased beneficial flora including Ruminococcaceae UCG-005, Prevotellaceae NK3B31, Weissella paramesenteroides, Lactobacillus reuteri, and Lactobacillus murinus and decreased harmful flora including Mucispirillum, Rodentibacter, and Staphylococcus aureus. This study pioneerly provided scientific evidences for the potential effects of water-soluble forms of silicon intake on antioxidant activity, gastrointestinal function, and gut microbiota modulation.

Association of digoxin with mortality in patients with advanced chronic kidney disease: A population-based cohort study

Digoxin is commonly prescribed for heart failure and atrial fibrillation, but there is limited data on its safety in patients with chronic kidney disease (CKD). We conducted a population-based cohort study using the pre-end stage renal disease (ESRD) care program registry and the National Health Insurance Research Database in Taiwan. Of advanced CKD patient cohort (N = 31,933), we identified the digoxin user group (N = 400) matched with age and sex non-user group (N = 2,220). Multivariable Cox proportional hazards and sub-distribution hazards models were used to evaluate the association between digoxin use and the risk of death, cardiovascular events (acute coronary syndrome, ischemic stroke, or hemorrhagic stroke) and renal outcomes (ESRD, rapid decline in estimated glomerular filtration rate-eGFR, or acute kidney injury). Results showed that all-cause mortality was higher in the digoxin user group than in the non-user group, after adjusting for covariates (adjusted hazard ratio, aHR 1.63; 95% CI 1.23-2.17). The risk for acute coronary syndrome (sub-distribution hazard ratio, sHR 1.18; 95% CI 0.75-1.86), ischemic stroke (sHR 1.42; 95% CI 0.85-2.37), and rapid eGFR decline (sHR 1.00 95% CI 0.78-1.27) was not significantly different between two groups. In conclusion, our study demonstrated that digoxin use was associated with increased mortality, but not cardiovascular events or renal function decline in advanced CKD patients. This finding warns the safety of prescribing digoxin in this population. Future prospective studies are needed to overcome the limitations of cohort study design.

IgM mesangial deposition as a risk factor for relapses of adult-onset minimal change disease

BACKGROUND

Immunoglobulin M (IgM) mesangial deposition in pediatric minimal change disease (MCD) has been reported to be associated with steroid dependence and poor renal outcomes. However, the evidence linking the impacts of IgM mesangial deposition to the treatment prognosis in adult-onset MCD is still elusive.

METHODS

In this retrospective cohort study, 37 adult patients with MCD received kidney biopsies from January 2010 to May 2020. Immunofluorescence microscopy was performed and the patients dichotomized according to IgM mesangial deposition (12 patients with positive IgM deposition; 25 patients with negative IgM deposition). We analyzed the clinical features, the dosage of immunosuppressive agents, and the response to treatment for 2 years between the two groups.

RESULTS

Analysis of the clinical symptoms, the dosage of immunosuppressive treatment, and the time to remission revealed no statistical difference between the groups. However, compared to the negative IgM group, the frequency of relapses was significantly higher in the positive IgM group during the two-year follow-up period (the negative IgM group 0.25 episodes/year; the positive IgM group 0.75 episodes/year, p = 0.029). Furthermore, multivariate linear regression revealed that the positivity of IgM mesangial deposition is independently associated with the frequency of relapses (regression coefficient B 0.450, 95% CI 0.116-0.784, p = 0.010).

CONCLUSIONS

Our findings indicated that adult-onset MCD patients with IgM mesangial deposition have a high risk of relapses. Therefore, intensive monitoring of disease activity should be considered in MCD adults with IgM mesangial deposition.

Systemic oxidative stress and cognitive function in Parkinson's disease with different PWMH or DWMH lesions

BACKGROUND

Parkinson's disease (PD), frequently accompanied by cognitive impairments, is associated with systemic oxidative stress and abnormal structural changes on brain images. We aimed to identify the correlation between systemic oxidative stress and cognitive function in PD patients with different periventricular white matter hyperintensities (PWMH) and deep white matter hyperintensities (DWMH).

METHODS

A total of 146 participants with idiopathic PD underwent brain MRI, which revealed PWMH and DWMH. The number of lesions were evaluated using the Fazekas criteria. Systemic oxidative stress was determined as early or late phase changes in leukocyte apoptosis and its subsets by flow cytometry. Cognitive functions, including attention, executive function, memory, language, and visual space, were assessed.

RESULTS

For different DWMH, the leukocyte apoptosis and its subsets were significantly different.. However, there were no significant differences in oxidative stress biomarkers in PD patients with different PWMH. Attention and memory were significantly decreased in patients with more advanced DWMH injuries. Attention, memory, and language were significantly impaired in patients with worse PWMH lesions.

CONCLUSION

Significant oxidative stress biomarker alternations in PD patients with DWMH, but not PWMH, might be associated with white matter injury. Systemic inflammatory responses may contribute to deep white matter damage in PD. Further, more cognitive deficits were seen in PD patients with worse deep white matter lesions, especially in moderate to severe periventricular white matter injury.

TRIAL REGISTRATION

Retrospective study.

Characterization of TMAO productivity from carnitine challenge facilitates personalized nutrition and microbiome signatures discovery

The capability of gut microbiota in degrading foods and drugs administered orally can result in diversified efficacies and toxicity interpersonally and cause significant impact on human health. Production of atherogenic trimethylamine N-oxide (TMAO) from carnitine is a gut microbiota-directed pathway and varies widely among individuals. Here, we demonstrated a personalized TMAO formation and carnitine bioavailability from carnitine supplements by differentiating individual TMAO productivities with a recently developed oral carnitine challenge test (OCCT). By exploring gut microbiome in subjects characterized by TMAO producer phenotypes, we identified 39 operational taxonomy units that were highly correlated to TMAO productivity, including Emergencia timonensis, which has been recently discovered to convert γ-butyrobetaine to TMA in vitro. A microbiome-based random forest classifier was therefore constructed to predict the TMAO producer phenotype (AUROC = 0.81) which was then validated with an external cohort (AUROC = 0.80). A novel bacterium called Ihubacter massiliensis was also discovered to be a key microbe for TMA/TMAO production by using an OCCT-based humanized gnotobiotic mice model. Simply combining the presence of E. timonensis and I. massiliensis could account for 43% of high TMAO producers with 97% specificity. Collectively, this human gut microbiota phenotype-directed approach offers potential for developing precision medicine and provides insights into translational research. Video Abstract.

Fabrication and Physical Properties of Single-Crystalline Βeta-FeSi2 Nanowires

In this study, self-catalyzed β-FeSi₂ nanowires, having been wanted but seldom achieved in a furnace, were synthesized via chemical vapor deposition method where the fabrication of β-FeSi₂ nanowires occurred on Si (100) substrates through the decomposition of the single-source precursor of anhydrous FeCl₃ powders at 750-950 °C. We carefully varied temperatures, duration time, and the flow rates of carrier gases to control and investigate the growth of the nanowires. The morphology of the β-FeSi₂ nanowires was observed with scanning electron microscopy (SEM), while the structure of them was analyzed with X-ray diffraction (XRD) and transmission electron microscopy (TEM). The growth mechanism has been proposed and the physical properties of the iron disilicide nanowires were measured as well. In terms of the magnetization of β-FeSi₂, nanowires were found to be different from bulk and thin film; additionally, longer β-FeSi₂ nanowires possessed better magnetic properties, showing the room-temperature ferromagnetic behavior. Field emission measurements demonstrate that β-FeSi₂ nanowires can be applied in field emitters.

Timing of kidney biopsy in type 2 diabetic patients: a stepwise approach

BACKGROUND

Diabetic nephropathy (DN) is the most prevalent cause of renal disease in type 2 diabetic patients and is usually diagnosed clinically. A kidney biopsy is considered when non-diabetic renal disease (NDRD) is suspected, such as rapid progression in renal function impairment and severe proteinuria. Still, there is yet no consensus on the timing of kidney biopsy in type 2 diabetic patients. This study aims to identify markers that can help differentiate between DN and NDRD and guide the decision of kidney biopsy.

METHODS

We retrospectively reviewed patients with type 2 diabetes who received kidney biopsy from 2008 to 2017 at Taipei Veterans General Hospital. Ophthalmologist consultation and outpatient records, diagnosis of kidney biopsy, laboratory data, and clinical characteristics were collected.

RESULTS

This study enrolled 160 type 2 diabetic patients, among which 120 (75%) had isolated DN and 40 (25%) had NDRD ± DN (26 had isolated NDRD, and 14 had NDRD superimposed on DN). In multivariate logistic regression analysis, DM duration (odds ratio [OR]: 0.907; 95% confidence interval [CI]: 0.842-0.977; P = 0.01), diabetic retinopathy (OR: 0.196; 95% CI: 0.061-0.627; P = 0.006), and urinary RBC (OR: 1.068; 95% CI: 1.024-1.115; P = 0.002) were independent predictors of NDRD. In patients with diabetic retinopathy (n = 112, 70%), the presence of proliferative diabetic retinopathy, pan-retinal photocoagulation, and hematuria were factors predicting NDRD; and in patients without diabetic retinopathy (n = 48, 30%), short DM duration and hematuria were factors predicting NDRD.

CONCLUSIONS

Using diabetic retinopathy, DM duration, and hematuria, we developed a 3-step approach to stratify patients into three categories with the different likelihoods of having NDRD. Then different strategies could be taken accordingly. Our stepwise approach is easy to follow and may serve as an appropriate and useful tool to help clinicians in making decisions of kidney biopsy in type 2 DM patients presenting with kidney diseases.

EpiMOLAS: an intuitive web-based framework for genome-wide DNA methylation analysis

BACKGROUND

DNA methylation is a crucial epigenomic mechanism in various biological processes. Using whole-genome bisulfite sequencing (WGBS) technology, methylated cytosine sites can be revealed at the single nucleotide level. However, the WGBS data analysis process is usually complicated and challenging.

RESULTS

To alleviate the associated difficulties, we integrated the WGBS data processing steps and downstream analysis into a two-phase approach. First, we set up the required tools in Galaxy and developed workflows to calculate the methylation level from raw WGBS data and generate a methylation status summary, the mtable. This computation environment is wrapped into the Docker container image DocMethyl, which allows users to rapidly deploy an executable environment without tedious software installation and library dependency problems. Next, the mtable files were uploaded to the web server EpiMOLAS_web to link with the gene annotation databases that enable rapid data retrieval and analyses.

CONCLUSION

To our knowledge, the EpiMOLAS framework, consisting of DocMethyl and EpiMOLAS_web, is the first approach to include containerization technology and a web-based system for WGBS data analysis from raw data processing to downstream analysis. EpiMOLAS will help users cope with their WGBS data and also conduct reproducible analyses of publicly available data, thereby gaining insights into the mechanisms underlying complex biological phenomenon. The Galaxy Docker image DocMethyl is available at https://hub.docker.com/r/lsbnb/docmethyl/. EpiMOLAS_web is publicly accessible at http://symbiosis.iis.sinica.edu.tw/epimolas/.

Full-Spectrum Analysis of Perovskite-Based Surface Plasmon Nanolasers

We systematically studied the characteristics of hybrid perovskite-based surface plasmon nanolasers. If one changes the anion composition of perovskites, the emission wavelength can be easily tuned. We conducted in full-spectrum modeling that featured hybrid perovskite nanowires placed on different SiO₂-coated metallic (Au, Ag, and Al) plates. The proposed nanocavities that supported plasmonic gap modes exhibited distinguished properties of nanolasers, such as low-transparency threshold-gain and low lasing threshold. The corresponding experimental results for the MAPbBr₃ nanolaser on Ag revealed the low-threshold operation. These superior features were attributed to enhanced light-matter interaction with strong coupling. Therefore, the proposed scheme, integrated with hybrid perovskite as gain material, provides an excellent platform for nanoscale plasmon lasing in the visible to near-infrared spectra.

Is left-behind status related to differences in sexual health of Armenian mothers? Evidence from the Demographic and Health Survey in 2010 and 2015

Background

Migration caused by poverty is a growing public health issue around the world. Migrants are at heightened risk of HIV/STIs and yet the vulnerability to poor sexual health of their left-behind partners, in relation to their household wealth, remain understudied. This investigation examines differences in sexual health from 2010 to 2015 among Armenian mothers, with a specific focus on their left-behind migration status and household wealth.

Methods and findings

Using the population-based Demographic and Health Surveys from Armenia, multilevel logistic models were used to examine the various relationships between sexual health, left-behind status, and household wealth. The multivariate analysis results showed that self-reported sexually transmitted infection (STI) symptoms (AOR = 1.45; p<0.01) and intimate partner violence (IPV) (AOR = 1.45; p<0.01) increased from 2010 to 2015; furthermore, negotiation power over sex (AOR = 0.77; p<0.01) declined among Armenian mothers. Left-behind mothers (LBMs) were more likely to report STI symptoms than their non-LBM counterparts (AOR = 1.61; p<0.01). In addition, significant differences in sexual health between LBMs and non-LBMs with different levels of household wealth were observed. The poorest wealth quintiles were associated with a higher likelihood of self-reported STI symptoms (AOR = 1.74; p<0.05) and IPV (AOR = 1.78; p<0.01), as well as a lower likelihood of utilizing HIV testing (AOR = 0.48; p<0.01) and negotiating power over sex (AOR = 0.47; p<0.01).

Conclusions

This study strives to fill gaps in the literature related to the relationship between left-behind status, household wealth, and sexual health among Armenian mothers in a context of economic expansion. Among these mothers, poor sexual health outcomes increased from 2010 to 2015. Both low household wealth and a left-behind status were associated with adverse sexual health outcomes. These findings suggest future campaigns aimed at improving the sexual health of Armenian mothers need to be migration-status appropriate and socioeconomic-sensitive.

Quantifying the level of difficulty to treat major depressive disorder with antidepressants: Treatment Resistance to Antidepressants Evaluation Scale

BACKGROUND

The present study aimed to develop a new scale to evaluate the level of difficulty in treating major depressive disorder with antidepressants based on the lifetime treatment profile.

METHODS

In addition to evaluating the difficulty of treatment with antidepressants (A subscale), the Treatment Resistance to Antidepressants Evaluation Scale (TRADES) is comprised of a subscale to account for the attributes that compromise the efficacy of treatment (B subscale). One hundred and six participants aged 18 to 65 years with remitted major depressive disorder were enrolled. Eligible cases were those with at least 2 years from disease onset until the scoring date of the TRADES (the index date), with a complete treatment record. Various psychosocial and clinical features, such as neuroticism, harm avoidance, and utilization of psychiatric services, were used to validate the TRADES.

RESULTS

The mean duration of the course before and after the index date were 5.5 ± 3.5 and 3.1 ± 1.7 years, respectively. In a multiple regression analysis, the final total scores of the TRADES independently correlated with higher levels of neuroticism and harm avoidance. Total scores were also associated with a higher utilization of psychiatric outpatient and admission services before the index date. Furthermore, it is thought that total scores could predict a higher number of visits to psychiatric outpatient, emergency, and admission services following the index date.

CONCLUSIONS

The TRADES has acceptable validity and could help to quantify the level of treatment difficulty with antidepressants in major depressive disorder.

A right whale (Mysticeti, Balaenidae) from the Pleistocene of Taiwan

Current patterns of biological distribution result from the deep past. Of particular interest, some closely related species appear at high latitudes of both hemispheres, but not in between, a pattern known as antitropical distribution. However, the timing, pathway, and drivers of antitropical distributions remain mostly unknown. Here we describe a new fossil, a left tympanic bulla (part of the ear bones), from the Middle/Late Pleistocene (0.78-0.01 mya, but not excluding the possibility of Holocene in age, as the specimen was dredged from the sea bottom and the geological horizon remains uncertain) of Taiwan. The tympanic bulla is diagnostic in baleen whales, and this specimen shows morphological features that are identical to extant Eubalaena, including: relatively large size (the anteroposterior length is 117 mm); rectangular outline in medial view; short anterior lobe, judging from the remaining of the lateral furrow; squared anterior margin; prominent transverse crease on the involucrum; transversely compressed in anterior view; well-developed and rounded outer lip; and parallel involucral and main ridges. Although incomplete, the morphological characters and overall similarity to extant Eubalaena allow a reliable taxonomic assignment to Eubalaena sp. The occurrence of a Pleistocene Eubalaena on the southern margin of the western North Pacific is the first balaenid fossil evidence indicative of the biotic interchange between two hemispheres leading to the origin of antitropical distribution in the Pleistocene; alternatively, this specimen might merely represent an extra-limital record of the North Pacific Eubalaena. Furthermore, this find suggests that the Eubalaena interchange, being one of the largest species displaying antitropical distribution pairs in the history of life, likely took place along the western Pacific. Notably, this does not preclude the Eubalaena interchange from other routes, such as the eastern Pacific or the Atlantic Ocean, and future finds should test the scenario for the biotic interchange between Northern and Southern Hemispheres of Eubalaena.

Age-period-cohort analysis with a constant-relative-variation constraint for an apportionment of period and cohort slopes

Age-period-cohort analysis of incidence and/or mortality data has received much attention in the literature. To circumvent the non-identifiability problem inherent in the age-period-cohort model, additional constraints are necessary on the parameters estimates. We propose setting the constraint to reflect the different nature of the three temporal variables: age, period, and birth cohort. There are two assumptions in our method. Recognizing age effects to be deterministic (first assumption), we do not explicitly incorporate the age parameters into constraint. For the stochastic period and cohort effects, we set a constant-relative-variation constraint on their trends (second assumption). The constant-relative-variation constraint dictates that between two stochastic effects, one with a larger curvature gets a larger (absolute) slope, and one with zero curvature gets no slope. We conducted Monte-Carlo simulations to examine the statistical properties of the proposed method and analyzed the data of prostate cancer incidence for whites from 1973-2012 to illustrate the methodology. A driver for the period and/or cohort effect may be lacking in some populations. In that case, the CRV method automatically produces an unbiased age effect and no period and/or cohort effect, thereby addressing the situation properly. However, the method proposed in this paper is not a general purpose model and will produce biased results in many other real-life data scenarios. It is only useful in situations when the age effects are deterministic and dominant, and the period and cohort effects are stochastic and minor.

The neural substrate of self- and other-concerned wellbeing: An fMRI study

Happiness, or Subjective Well-Being (SWB), is generally considered as a peaceful and satisfied state accompanied by consistent and optimistic mood. Due to its subjective and elusive nature, however, wellbeing has only been scarcely investigated in the neuroimaging literature. In this study, we investigated its neural substrates by characterizing two different perspectives: self- or other-concerned wellbeing. In the present study, 22 participants evaluated the subjective happiness (with button presses 1 to 4) to 3 categories (intra- and inter-personal and neutral) of pre-rated pictures in a slow event-related fMRI. Because wellbeing is constantly featured by pleasure feelings after self-inspection, we predict that happier conditions, featured by “intra-personal vs. neutral” and “inter-personal vs. neutral” conditions, should yield higher BOLD activities in overlapping reward- and self-related regions. Indeed, medial prefrontal (mPFC), pregenual ACC (pACC), precuneus and posterior cingulate cortex (PCC) were revealed both by General Linear Model (GLM) (categorical contrasts) and parametric modulations (correlations with rating 1-4s), specifically, more connectivity between nucleus accumbens (NAcc) and mPFC, via additional psychophysiological interaction, or PPI, analyses. More interestingly, GLM and multivariate searchlight analyses jointly reveal the subdivision of mPFC and the PCC/precuneus, with anterior mPFC and dorsal PCC/precuneus more for interpersonal, posterior mPFC and ventral PCC/precuneus more for intrapersonal, SWB, respectively. Taken together, these results are not only consistent with the “cortical midline hypothesis of the self”, but also extending the “spatial gradients of self-to-other-concerned processing” from mPFC to including both mPFC and PCC/precuneus, making them two “hubs” of self-to-other-concerned wellbeing network.

Flexible Photocatalytic Paper with Cu2O and Ag Nanoparticle-Decorated ZnO Nanorods for Visible Light Photodegradation of Organic Dye

We report on the fabrication of flexible photocatalytic paper comprised of Cu₂O and Ag nanoparticle (NP)-decorated ZnO nanorods (NRs) and its application in visible light photodegradation of organic dye. ZnO NRs are first grown on a kraft paper substrate using a hydrothermal method. The NRs are subsequently decorated with Cu₂O, Ag, or both NPs formed by photoreduction processes. Scanning electron microscopy and X-ray diffraction analysis confirm the crystallinity of ZnO NRs. Transmission electron microscopy analysis confirms the compositions of the two types of NPs. Four different types of photocatalytic papers with a size of 10 × 10 cm² are prepared and used to degrade a 10-μM and 100-mL rhodamine B solution. The paper with Cu₂O and Ag NP-co-decorated ZnO NRs has the best efficiency with first-order kinetic constants of 0.017 and 0.041 min^-1 under the illumination of a halogen lamp and direct sunlight, respectively. The performance of the photocatalytic paper compares well with other substrate-supported ZnO nanocomposite photocatalysts. With the advantages of flexibility, light weight, nontoxicity, low cost, and ease of fabrication, the photocatalytic paper has good potential for visible light photocatalysis.

The effects of human parvovirus VP1 unique region in a mouse model of allergic asthma

Evidence has indicated that viral infection increases the risk of developing asthma. Although the association of human parvovirus B19 (B19V) or human bocavirus (HBoV) with respiratory diseases has been reported, little is known about the influence of the B19V-VP1u and HBoV-VP1u proteins on the symptoms of asthma. Herein, we investigated the systemic influence of subcutaneously injected B19V-VP1u and HBoV-VP1u recombinant proteins in an OVA-sensitized asthmatic mouse model. A significantly higher Penh ratio and IgE level were detected in the serum, bronchoalveolar lavage fluid (BALF) and the supernatant of a lymphocyte culture from mice treated with HBoV-VP1u or B19V-VP1u than in a lymphocyte culture from OVA-sensitized mice. Significantly higher levels of serum and BALF IgE, total IgG, IgG1, OVA-specific IgE and OVA-specific IgG1 were detected in mice treated with HBoV-VP1u or B19V-VP1u than in OVA-sensitized mice. Conversely, a significantly lower IgG2a level was detected in mice from the HBoV-VP1u or B19V-VP1u groups than in mice from the OVA group. The mice treated with HBoV-VP1u or B19V-VP1u exhibited more significant lung inflammatory indices, including elevated serum and BALF IL-4, IL-5, IL-10 and IL-13 levels; BALF lymphocyte, neutrophil and eosinophil counts, MMP-9 and MMP-2 activity; and the amount of lymphocyte infiltration, relative to those in the control mice or in those sensitized with OVA. These findings demonstrate that the subcutaneous injection of HBoV-VP1u or B19V-VP1u proteins in OVA-sensitized mice result in elevated asthmatic indices and suggest that human parvoviruses may increase the risk of developing airway inflammation in a mouse model of asthma.

Long-term outcomes after extracorporeal membrane oxygenation in patients with dialysis-requiring acute kidney injury: A cohort study

Background

Acute kidney injury (AKI) is a common complication of extracorporeal membrane oxygenation (ECMO) treatment. The aim of this study was to elucidate the long-term outcomes of adult patients with AKI who receive ECMO.

Materials and methods

The study analyzed encrypted datasets from Taiwan’s National Health Insurance Research Database. The data of 3251 patients who received first-time ECMO treatment between January 1, 2003, and December 31, 2013, were analyzed. Characteristics and outcomes were compared between patients who required dialysis for AKI (D-AKI) and those who did not in order to evaluate the impact of D-AKI on long-term mortality and major adverse kidney events.

Results

Of the 3251 patients, 54.1% had D-AKI. Compared with the patients without D-AKI, those with D-AKI had higher rates of all-cause mortality (52.3% vs. 33.3%; adjusted hazard ratio [aHR] 1.82, 95% confidence interval [CI] 1.53–2.17), chronic kidney disease (13.7% vs. 8.1%; adjusted subdistribution HR [aSHR] 1.66, 95% CI 1.16–2.38), and end-stage renal disease (5.2% vs. 0.5%; aSHR 14.28, 95% CI 4.67–43.62). The long-term mortality of patients who survived more than 90 days after discharge was 22.0% (153/695), 32.3% (91/282), and 50.0% (10/20) in the patients without D-AKI, with recovery D-AKI, and with nonrecovery D-AKI who required long-term dialysis, respectively, demonstrating a significant trend (Pfor trend <0.001).

Conclusion

AKI is associated with an increased risk of long-term mortality and major adverse kidney events in adult patients who receive ECMO.

Quantitative diagnosis of rotator cuff tears based on sonographic pattern recognition

The lifetime prevalence of shoulder pain is nearly 70% and is mostly attributable to subacromial disorders. A rotator cuff tear is the most severe form of subacromial disorders, and most occur in the supraspinatus. For clinical examination, shoulder ultrasound is recommended to detect supraspinatus tears. In this study, a computer-aided tear classification (CTC) system was developed to identify supraspinatus tears in ultrasound examinations and reduce inter-operator variability. The observed cases included 89 ultrasound images of supraspinatus tendinopathy and 102 of supraspinatus tear from 136 patients. For each case, intensity and texture features were extracted from the entire lesion and combined in a binary logistic regression classifier for lesion classification. The proposed CTC system achieved an accuracy rate of 92% (176/191) and an area under receiver operating characteristic curve (Az) of 0.9694. Based on its diagnostic performance, the CTC system has promise for clinical use.

Living arrangements and disability-free life expectancy in the United States

No studies have investigated the association between living arrangements and disability-free life expectancy in the United States, nor worldwide. This study aims to examine the differences in total and disability-free life expectancy among older Americans according to living arrangements. Data from the Health and Retirement Study (1998 to 2014) for non-Hispanic whites aged 50 and over (N = 21,612). Disability-free life expectancy by gender, living arrangement, and education are obtained from incidence-based multistate life tables. Overall, those who live only with their spouses/partners live 1-19 years longer with 3-25 more years without disability and 1-7 fewer years with disability than do those with other living arrangements. Among those with the same living arrangement, the higher educated live up to 6 years longer with up to 8 more years in a disability-free state and up to 2 fewer years in a disabled state. The study shows strong association between living arrangement and disability-free life expectancy by gender and education. Long-term care policy should take into account the length of life with/without disability by living arrangements and socioeconomic status and make use of the potential family resources.

PePIF1, a P-lineage of PIF-like transposable element identified in protocorm-like bodies of Phalaenopsis orchids

BACKGROUND

Orchids produce a colorless protocorm by symbiosis with fungi upon seed germination. For mass production of orchids, the prevailing approaches are both generation of protocorm-like bodies (PLBs) from callus and multiplication of adventitious buds on inflorescence. However, somaclonal variations occur during micropropagation.

RESULTS

We isolated the two most expressed transposable elements belonging to P Instability Factor (PIF)-like transposons. Among them, a potential autonomous element was identified by similarity analysis against the whole-genome sequence of Phalaenopsis equestris and named PePIF1. It contains a 19-bp terminal inverted repeat flanked by a 3-bp target site duplication and two coding regions encoding ORF1- and transposase-like proteins. Phylogenetic analysis revealed that PePIF1 belongs to a new P-lineage of PIF. Furthermore, two distinct families, PePIF1a and PePIF1b, with 29 and 37 putative autonomous elements, respectively, were isolated, along with more than 3000 non-autonomous and miniature inverted-repeat transposable element (MITE)-like elements. Among them, 828 PePIF1-related elements were inserted in 771 predicted genes. Intriguingly, PePIF1 was transposed in the somaclonal variants of Phalaenopsis cultivars, as revealed by transposon display, and the newly inserted genes were identified and sequenced.

CONCLUSION

A PIF-like element, PePIF1, was identified in the Phalaenopsis genome and actively transposed during micropropagation. With the identification of PePIF1, we have more understanding of the Phalaenopsis genome structure and somaclonal variations during micropropagation for use in orchid breeding and production.

Decomposing the subclonal structure of tumors with two-way mixture models on copy number aberrations

Multistage tumorigenesis is a dynamic process characterized by the accumulation of mutations. Thus, a tumor mass is composed of genetically divergent cell subclones. With the advancement of next-generation sequencing (NGS), mathematical models have been recently developed to decompose tumor subclonal architecture from a collective genome sequencing data. Most of the methods focused on single-nucleotide variants (SNVs). However, somatic copy number aberrations (CNAs) also play critical roles in carcinogenesis. Therefore, further modeling subclonal CNAs composition would hold the promise to improve the analysis of tumor heterogeneity and cancer evolution. To address this issue, we developed a two-way mixture Poisson model, named CloneDeMix for the deconvolution of read-depth information. It can infer the subclonal copy number, mutational cellular prevalence (MCP), subclone composition, and the order in which mutations occurred in the evolutionary hierarchy. The performance of CloneDeMix was systematically assessed in simulations. As a result, the accuracy of CNA inference was nearly 93% and the MCP was also accurately restored. Furthermore, we also demonstrated its applicability using head and neck cancer samples from TCGA. Our results inform about the extent of subclonal CNA diversity, and a group of candidate genes that probably initiate lymph node metastasis during tumor evolution was also discovered. Most importantly, these driver genes are located at 11q13.3 which is highly susceptible to copy number change in head and neck cancer genomes. This study successfully estimates subclonal CNAs and exhibit the evolutionary relationships of mutation events. By doing so, we can track tumor heterogeneity and identify crucial mutations during evolution process. Hence, it facilitates not only understanding the cancer development but finding potential therapeutic targets. Briefly, this framework has implications for improved modeling of tumor evolution and the importance of inclusion of subclonal CNAs.

Mutational monitoring of EGFR T790M in cfDNA for clinical outcome prediction in EGFR-mutant lung adenocarcinoma

Several ultra-sensitive methods for T790M in plasma cell-free DNA (cfDNA) have been developed for lung cancer. The correlation between mutation-allele frequency (MAF) cut-off, drug responsiveness, and outcome prediction is an unmet needs and not fully addressed. An innovative combination of peptide nucleic acid (PNA) and Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) was used to proof of concept for monitoring cfDNA T790M in EGFR-mutant patients. Mutant enrichment by PNA was optimized and the detection limit was evaluated through serial dilutions. The cut-off value was identified by receiver-operating-characteristic (ROC) curve analysis utilizing serial sampled plasmas of patients from EGFR-tyrosine kinase inhibitor (TKI) pretreatment to progressive-disease (PD). Results, comparisons, and objective response rate (ORR) were analyzed in 103 patients’ tumor and cfDNA T790M, with 20 of them receiving an additional COBAS test. The detection limit was 0.1% MAF. The cut-off for PD and imminent PD was 15% and 5% with an ROC area under the curve (AUC) of 0.96 and 0.82 in 2 ml plasma. Detection sensitivity of cfDNA T790M was 67.4% and overall concordance was 78.6%. ORR was similar in T790M-positive cfDNA (69.6%) and tumor samples (70.6%) treated with osimertinib. Among 65 T790M-positive tumors, 15 were negative in cfDNA (23.1%). Seven of 38 T790M-positive cfDNA samples were negative in the tumors (18.4%). PNA-MALDI-TOF MS had a higher detection rate than COBAS. In conclusion, identification of T790M cut-off value in cfDNA improves cancer managements. We provide a strategy for optimizing testing utility, flexibility, quality, and cost in the clinical practice.

Assessing the severity of positive valence symptoms in initial psychiatric evaluation records: Should we use convolutional neural networks?

BACKGROUND AND OBJECTIVE

Efficiently capturing the severity of positive valence symptoms could aid in risk stratification for adverse outcomes among patients with psychiatric disorders and identify optimal treatment strategies for patient subgroups. Motivated by the success of convolutional neural networks (CNNs) in classification tasks, we studied the application of various CNN architectures and their performance in predicting the severity of positive valence symptoms in patients with psychiatric disorders based on initial psychiatric evaluation records.

METHODS

Psychiatric evaluation records contain unstructured text and semi-structured data such as question-answer pairs. For a given record, we tokenise and normalise the semi-structured content. Pre-processed tokenised words are represented as one-hot encoded word vectors. We then apply different configurations of convolutional and max pooling layers to automatically learn important features from various word representations. We conducted a series of experiments to explore the effect of different CNN architectures on the classification of psychiatric records.

RESULTS

Our best CNN model achieved a mean absolute error (MAE) of 0.539 and a normalized MAE of 0.785 on the test dataset, which is comparable to the other well-known text classification algorithms studied in this work. Our results also suggest that the normalisation step has a great impact on the performance of the developed models.

CONCLUSIONS

We demonstrate that normalisation of the semi-structured contents can improve the MAE among all CNN configurations. Without advanced feature engineering, CNN-based approaches can provide a comparable solution for classifying positive valence symptom severity in initial psychiatric evaluation records. Although word embedding is well known for its ability to capture relatively low-dimensional similarity between words, our experimental results show that pre-trained embeddings do not improve the classification performance. This phenomenon may be due to the inability of word embeddings to capture problem specific contextual semantic information implying the quality of the employing embedding is critical for obtaining an accurate CNN model.

Anti-cancer effects of 3,5-dimethylaminophenol in A549 lung cancer cells

Exposure to 3,5-dimethylaminophenol (3,5-DMAP), the metabolite of the 3-5-dimethylaniline, was shown to cause high levels of oxidative stress in different cells. The aim of the present work was to observe whether this metabolite can lead to cytotoxicity, oxidative stress, DNA damage and cell cycle changes in non-small cell lung cancer A549 cells. 3,5-DMAP caused a dose-dependent increase in cytotoxicity, generation of superoxide (O₂^-.), inductions in the enzyme activities orchestrating cellular antioxidant balance, increases in lipid peroxidation as well as DNA damage. However, 3,5-DMAP showed significantly lower cytotoxicity towards human lung fibroblast (HLF) cells. 3,5-DMAP also led to molecular events, like inducing apoptotic markers (ie. p53, Bad, Bax and cytochrome c); decreasing anti-apoptotic proteins (Bcl-2) and alterations in cell cycle. Our findings indicate that the cytotoxicity caused by this particular alkylaniline metabolite led to initiation of caspase 3-mediated apoptosis. Furthermore, 3,5-DMAP attenuated carcinogenic properties like migration capacity of A549 cells and eventually inhibited growth of A549 cells in an in vivo mouse model. Tumor sections showed that 3,5-DMAP down-regulated c-Myc expression but up-regulated p53 and cytochrome c, all of which might result in tumor growth arrest. Co-treatment with N-acetylcysteine provided reductions in cytotoxicity and positively modulated genetic events induced by 3,5-DMAP in A549 cells. In conclusion, our findings demonstrate 3,5-DMAP may be a potential anti-cancer drug in cancer, due to its self redox cycling properties.

Transforming growth factor beta 1 mediates the low-frequency vertical vibration enhanced production of tenomodulin and type I collagen in rat Achilles tendon

Vertical vibration (VV) is a whole-body vibration with mechanical loading that commonly used in rehabilitation and sports training to increase athlete muscle strength. Our previous study showed that low-magnitude, low-frequency VV at 8 Hz and 10 Hz increased myoblast myogenesis. Herein, we investigated whether a VV frequency at low-frequency 5-10 Hz has anabolic effects on tenocytes and improves tendon stiffness. In primary tenocytes, 10 Hz VV treatment increased the tenogenic marker gene expression of tenomodulin and extracellular matrix type I collagen but decreased decorin expression. qPCR and Enzyme-Linked Immunosorbent Assay (ELISA) results showed that TGF-β1 expression was increased in tenocytes after 3 days of 10 Hz VV treatment in vitro and in Achilles tendons after 3 weeks in vivo. Tenomodulin expression and Achilles tendon stiffness were significantly increased in Achilles tendons after 3 weeks in vivo. We also showed that the TGF-β1 receptor inhibitor SB431542 (10 μM) decreased the expression of tenomodulin and type I collagen but increased the decorin expression in tenocytes. These results indicated that the 10 Hz VV stimulated anabolic effects in tenocytes by increasing TGF-β1 expression that subsequently increases the expression of tenomodulin and type I collagen, and increased the Achilles tendon stiffness. This study provides insight into the low-frequency 10 Hz VV treatment improves tendon properties and can minimizes the risk of ligament/tendon reinjure during rehabilitation.

Plasma β-Amyloids and Tau Proteins in Patients with Vascular Cognitive Impairment

Increases in plasma of β-amyloids (Aβ) and tau proteins have been noted in patients with Alzheimer's dementia (AD). Our study investigated the associations of plasma Aβ and tau proteins with dementia in stroke patients. This cross-sectional study recruited 24 controls (mean age: 67.4 ± 7.5 years, 33.3% male), 27 stroke patients without dementia (mean age: 70.7 ± 6.9 years, 60.7% male), 34 stroke patients with dementia (mean age: 78.3 ± 5.3 years, 45.5% male, Clinical Dementia Ranking (CDR): 1.46 ± 0.63), and 21 AD patients (mean age: 77.1 ± 9.1 years, 42.9% male, CDR: 1.43 ± 0.60) from a medical center. Dementia was defined as a CDR scale score of ≥ 1. The plasma levels of Aβ-40, Aβ-42, and tau were analyzed using immunomagnetic reduction. One-way analysis of variance was used to compare the differences in measured protein levels between the groups. The results indicated that plasma levels of tau and Aβ-42, but not Aβ-40, in stroke patients were significantly higher than in the controls. After adjustment for age, sex, diabetes mellitus, hypertension, and hyperlipidemia, only plasma level of Aβ-42 remained significantly higher in stroke patients with dementia than in those without dementia (OR 1.85, 1.25-2.75, p = 0.002). In summary, our results suggest that plasma Aβ-42 is a potential biomarker for dementia in stroke patients.

Few-Layer Graphene Sheet-Passivated Porous Silicon Toward Excellent Electrochemical Double-Layer Supercapacitor Electrode

Few-layer graphene sheet-passivated porous silicon (PSi) as an outstanding electrochemical double-layer supercapacitor electrode was demonstrated. The PSi matrix was formed by electrochemical etching of a doped silicon wafer and was further surface-passivated with few-layer graphene sheets by a Ni-assisted chemical vapor deposition process where a wide range of porous PSi structures, including mesoporous, macroporous, and hybrid porous structures were created during the graphene growth as temperature increases. The microstructural and graphene-passivation effects on the capacitive performance of the PSi were investigated in detail. The hybrid porous PSi electrode, optimized in terms of capacitive performances, achieves a high areal capacitance of 6.21 mF/cm² at an ultra-high scan rate of 1000 mV/s and an unusual progressing cyclic stability of 131% at 10,000 cycles. Besides mesopores and macropores, micropores were introduced onto the surfaces of the passivating few-layer graphene sheets with a KOH activation process to further increase the functioning surface area of the hierarchical porous PSi electrode, leading to a boost in the areal capacitance by 31.4% up to 8.16 mF/cm². The present designed hierarchical porous PSi-based supercapacitor proves to be a robust energy storage device for microelectronic applications that require stable high rate capability.

Characterization of candidate genes involved in halotolerance using high-throughput omics in the halotolerant bacterium Virgibacillus chiguensis

We previously used whole-genome sequencing and Tn5 transposon mutagenesis to identify 16 critical genes involved in the halotolerance of Halomonas beimenensis, a species in the phylum Proteobacteria. In this present study, we sought to determine if orthologous genes in another phylum are also critical for halotolerance. Virgibacillus spp. are halotolerant species that can survive in high-saline environments. Some Virgibacillus species are used in different aspects of food processing, compatible solute synthesis, proteinase production, and wastewater treatment. However, genomic information on Virgibacillus chiguensis is incomplete. We assembled a draft V. chiguensis strain NTU-102 genome based on high-throughput next-generation sequencing (NGS) and used transcriptomic profiling to examine the high-saline response in V. chiguensis. The V. chiguensis draft genome is approximately 4.09 Mbp long and contains 4,166 genes. The expression profiles of bacteria grown in 5% and 20% NaCl conditions and the corresponding Gene Ontology (GO) and clusters of orthologous groups (COG) categories were also analyzed in this study. We compared the expression levels of these 16 orthologs of halotolerance-related genes in V. chiguensis and H. beimenensis. Interestingly, the expression of 7 of the 16 genes, including trkA2, smpB, nadA, mtnN2, rfbP, lon, and atpC, was consistent with that in H. beimenensis, suggesting that these genes have conserved functions in different phyla. The omics data were helpful in exploring the mechanism of saline adaptation in V. chiguensis, and our results indicate that these 7 orthologs may serve as biomarkers for future screening of halotolerant species in the future.

Decreased risk of pneumonia in stroke patients receiving acupuncture: A nationwide matched-pair retrospective cohort study

Background

Acupuncture treatment is common among stroke patients, but there is limited information available on whether acupuncture effectively prevents post-stroke pneumonia. The aim of this study was to analyze the differential risk of pneumonia after stroke between patients who did and did not receive acupuncture after discharge.

Methods

We used the Taiwan National Health Insurance Research Database to conduct a retrospective cohort study using propensity score matched-pairs of new stroke patients in 2000–2004 who did and did not receive acupuncture post-stroke. Both cohorts were followed up until the end of 2009 for new-onset pneumonia. After correcting for immortal time bias, the incidence and adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) of pneumonia associated with acupuncture use were calculated using multivariate Cox proportional hazard models.

Results

Overall, 12557 stroke patients with 12557 paired controls were included in the analysis; pneumonia was diagnosed in 6796 (27.1%). Stroke patients receiving acupuncture had a lower incidence of pneumonia than those without acupuncture (53.4 vs. 58.9 per 1000 person-years), with an adjusted HR of 0.86 (95% CI 0.82–0.90). The association between pneumonia risk and acupuncture use was significant in men (HR 0.92, 95% CI 0.86–0.98) and women (HR 0.79, 95% 0.70–0.82) and was also observed in every age group from 20–79 years.

Conclusion

Stroke patients receiving acupuncture had a lower risk of pneumonia than those who did not. Further randomized control studies are needed to validate the protective effect of acupuncture on the risk of pneumonia among stroke patients.

MDM2 Degrades Deacetylated Nucleolin Through Ubiquitination to Promote Glioma Stem-Like Cell Enrichment for Chemotherapeutic Resistance

Glioblastoma multiforme (GBM) is the most fatal of all brain cancers, and the standard care protocol for GBM patients is surgical tumor resection followed by radiotherapy and temozolomide (TMZ)-mediated chemotherapy. However, tumor recurrence frequently occurs, and recurrent GBM exhibits more malignancy and less sensitivity in response to chemotherapy. The malignancy and drug resistance primarily reflect the small population of glioma stem-like cells (GSC). Therefore, understanding the mechanism that controls GSC enrichment is important to benefit the prognosis of GBM patients. Nucleolin (NCL), which is responsible for ribosome biogenesis and RNA maturation, is overexpressed in gliomas. However, the role of NCL in GSC development and drug resistance is still unclear. In this study, we demonstrate that NCL attenuated GSC enrichment to enhance the sensitivity of GBM cells in response to TMZ. In GSC enrichment, NCL was significantly reduced at the protein level as a result of decreased protein stability. In particular, the inhibition of HDAC activity by suberoylanilide hydroxamic acid rescued NCL acetylation accompanied by the loss of mouse double minute 2 homolog (MDM2)-mediated ubiquitination. In addition, we found that NCL ubiquitination resulted from the activation of STAT3- and JNK-mediated signaling in GSC. Moreover, NCL inhibited the formation of stem-like spheres by attenuating the expression of Sox2, Oct4, and Bmi1. Furthermore, NCL sensitized the response of GBM cells to TMZ. Based on these findings, NCL expression is a potential indicator to predict chemotherapeutic efficiency in GBM patients.

The development of functional mapping by three sex-related loci on the third whorl of different sex types of Carica papaya L

Carica papaya L. is an important economic crop worldwide and is used as a model plant for sex-determination research. To study the different flower sex types, we screened sex-related genes using alternative splicing sequences (AS-seqs) from a transcriptome database of the three flower sex types, i.e., males, females, and hermaphrodites, established at 28 days before flowering using 15 bacterial artificial chromosomes (BACs) of C. papaya L. After screening, the cDNA regions of the three sex-related loci, including short vegetative phase-like (CpSVPL), the chromatin assembly factor 1 subunit A-like (CpCAF1AL), and the somatic embryogenesis receptor kinase (CpSERK), which contained eight sex-related single-nucleotide polymorphisms (SNPs) from the different sex types of C. papaya L., were genotyped using high-resolution melting (HRM). The three loci were examined regarding the profiles of the third whorl, as described below. CpSVPL, which had one SNP associated with the three sex genotypes, was highly expressed in the male and female sterile flowers (abnormal hermaphrodite flowers) that lacked the fourth whorl structure. CpCAF1AL, which had three SNPs associated with the male genotype, was highly expressed in male and normal hermaphrodite flowers, and had no AS-seqs, whereas it exhibited low expression and an AS-seqs in intron 11 in abnormal hermaphrodite flowers. Conversely, carpellate flowers (abnormal hermaphrodite flowers) showed low expression of CpSVPL and AS-seqs in introns 5, 6, and 7 of CpSERK, which contained four SNPs associated with the female genotype. Specifically, the CpSERK and CpCAF1AL loci exhibited no AS-seq expression in the third whorl of the male and normal hermaphrodite flowers, respectively, and variance in the AS-seq expression of all other types of flowers. Functional mapping of the third whorl of normal hermaphrodites indicated no AS-seq expression in CpSERK, low CpSVPL expression, and, for CpCAF1AL, high expression and no AS-seq expression on XY^h-type chromosomes.

A new scheme for strain typing of methicillin-resistant Staphylococcus aureus on the basis of matrix-assisted laser desorption ionization time-of-flight mass spectrometry by using machine learning approach

Methicillin-resistant Staphylococcus aureus (MRSA), one of the most important clinical pathogens, conducts an increasing number of morbidity and mortality in the world. Rapid and accurate strain typing of bacteria would facilitate epidemiological investigation and infection control in near real time. Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry is a rapid and cost-effective tool for presumptive strain typing. To develop robust method for strain typing based on MALDI-TOF spectrum, machine learning (ML) is a promising algorithm for the construction of predictive model. In this study, a strategy of building templates of specific types was used to facilitate generating predictive models of methicillin-resistant Staphylococcus aureus (MRSA) strain typing through various ML methods. The strain types of the isolates were determined through multilocus sequence typing (MLST). The area under the receiver operating characteristic curve (AUC) and the predictive accuracy of the models were compared. ST5, ST59, and ST239 were the major MLST types, and ST45 was the minor type. For binary classification, the AUC values of various ML methods ranged from 0.76 to 0.99 for ST5, ST59, and ST239 types. In multiclass classification, the predictive accuracy of all generated models was more than 0.83. This study has demonstrated that ML methods can serve as a cost-effective and promising tool that provides preliminary strain typing information about major MRSA lineages on the basis of MALDI-TOF spectra.

The aldehyde dehydrogenase 2 polymorphisms on neuropsychological performance in bipolar II disorder with or without comorbid anxiety disorder

Anxiety disorders (ADs), the most common comorbid illnesses with bipolar disorder (BP) has been reported to associate with dopamine system. Dopamine, metabolized to 3,4-dihydroxyphenylacetic acid (DOPAC) by aldehyde dehydrogenase 2 (ALDH2), and the distribution of the ALDH2*1/*1, and ALDH2*1/*2+ALDH*2/*2 alleles in the Han Chinese general population is relatively equal. The association between dopamine metabolic enzymes and cognitive performance in patients with bipolar II disorder (BP-II) comorbid with AD is unclear. This study proposed to explore the role of ALDH2 polymorphisms on neuropsychological performance between BP-II comorbid with or without AD. One hundred ninety-seven BP-II patients with and without a comorbid AD were recruited and compared with 130 healthy controls (HCs). A polymerase chain reaction and a restriction fragment length polymorphism analysis were used to determine genotypes for ALDH2, and study participants underwent neuropsychological tests. An interaction between AD comorbidity and the ALDH2 polymorphisms was found in different domain of cognitive dysfunction in the BP-II patients. The ALDH2 polymorphisms might have different effects on the neuropsychological performance of BP-II patients with and without comorbid AD.

Enhanced Ferromagnetic Interaction in Modulation-Doped GaMnN Nanorods

In this report, ferromagnetic interactions in modulation-doped GaMnN nanorods grown on Si (111) substrate by plasma-assisted molecular beam epitaxy are investigated with the prospect of achieving a room temperature ferromagnetic semiconductor. Our results indicate the thickness of GaN layer in each GaN/MnN pair, as well as Mn-doping levels, are essential for suppressing secondary phases as well as enhancing the magnetic moment. For these optimized samples, structural analysis by high-resolution X-ray diffractometry and Raman spectroscopy verifies single-crystalline modulation-doped GaMnN nanorods with Ga sites substituted by Mn atoms. Energy dispersive X-ray spectrometry shows that the average Mn concentration can be raised from 0.4 to 1.8% by increasing Mn fluxes without formation of secondary phases resulted in a notable enhancement of the saturation magnetization as well as coercive force in these nanorods.

Risk of recurrence in chronic hepatitis B patients developing hepatocellular carcinoma with antiviral secondary prevention failure

Background

Nucleos(t)ide analogues (NUCs) treatment can reduce the risk of hepatocellular carcinoma (HCC) development and recurrence in chronic hepatitis B (CHB) patients. However, the risk of recurrence in CHB patients who develop HCC despite NUC treatment remains unclear.

Methods

167 consecutive CHB patients receiving curative resection for HCC with NUC therapy after surgery were retrospectively enrolled. Thirty-eight patients who developed HCC despite NUC therapy for more than 1 year were defined as secondary prevention failure. The other 129 patients started NUC therapy after surgery. Factors associated with recurrence-free survival (RFS) and overall survival (OS) were evaluated.

Results

The 5-year RFS and OS rates were 44.7% and 77.3%, respectively. Sex, BMI, BCLC stage, AFP levels and cirrhosis status were the independent predictors of RFS, while microvascular invasion was the independent predictor of OS. The RFS was comparable between patients with and without NUC secondary prevention. In the subgroup analysis, the RFS was significantly worse in cirrhotic patients with secondary prevention failure (hazard ratio = 2.373, p = 0.009). Secondary prevention failure did not have adverse impact on OS. Among 84 patients with recurrence, 58.3% of the cases remained in BCLC stage A, and 53.6% received a second curative treatment. Long-term NUC therapy may lead to a decline of non-invasive indices of hepatic fibrosis in HCC patients.

Conclusions

In general, the risk of recurrence and survival are comparable between patients with and without secondary prevention failure. However, a higher risk of recurrence was observed in cirrhotic patients with secondary prevention failure.

The frequency of cancer predisposition gene mutations in hereditary breast and ovarian cancer patients in Taiwan: From BRCA1/2 to multi-gene panels

An important role of genetic factors in the development of breast cancer (BC) or ovarian cancer (OC) in Taiwanese (ethnic Chinese) patients has been suggested. However, other than germline BRCA1 or BRCA2 mutations, which are related to hereditary breast-ovarian cancer (HBOC), cancer-predisposition genes have not been well studied in this population. The aim of the present study was to more accurately summarize the prevalence of genetic mutations in HBOC patients using various gene panels ranging in size from BRCA1/2 alone to multi-gene panels. Among 272 HBOC patients analyzed, the prevalence of BRCA1, BRCA2 and non-BRCA1/2 pathogenic mutations was 7.7% (21/272), 6.8% (16/236) and 8.2% (13/159), respectively. The total mutation rate was 18.4% (50/272). Although no founder mutations were identified in this study, two recurrent mutations, BRCA1 (c.3607C>T) and BRCA2 (c.5164_5165 delAG), were found. The main pathogenic/likely pathogenic mutations in non-BRCA1/2 genes included ATM, BRIP1, FANCI, MSH2, MUYTH, RAD50, RAD51C and TP53. The prevalence rate of gene mutations in HBOC patients did not differ with respect to whether BC or OC was the first diagnosis or they presented a family history of the disease or their age at diagnosis. HBOC patients with both BC and OC exhibited a higher prevalence rate of mutations (50.0%) than patients with OC (25.0%) or BC (8.6%) alone. In conclusion, evaluation of hereditary cancer risk in Taiwan HBOC patients, particularly individuals with double cancer, is strongly encouraged. Panel testing can yield additional genomic information, and widespread and well-designed panel testing will help in assessing more accurate mutational prevalence of risk genes.

Are vent crab behavioral preferences adaptations for habitat choice?

Hydrothermal vent organisms are adapted to their extreme and patchily distributed habitats. They are expected to have evolved mechanisms that keep them in their specific habitation. Since little is known about the recruitment or habitat selection of HV organisms such as brachyurans, we examined the properties of several hydrothermal vent-associated cues on the behavior of the hydrothermal vent (HV) crab Xenograpsus testudinatus in the laboratory that were contrasted by the offering of non-vent cues. This crab species is endemic and dominates the vent fauna of Turtle Island off the NE coast of Taiwan. HV crabs were separately and in combination offered the following vent-specific cues: (1) sulfuric sediment, (3) air-bubbling, (4) elevated temperature, (5) dead settled zooplankton, (7) other crabs, and (8) shade. The non-vent-specific cues were: (2) quarz sediment, (6) dead fish, (8) light. These cues were provided on either side of a two-choice chamber. The movement of individual crabs was monitored: as initial and final choices, and as the proportion of time the crabs spent in each compartment (resident time). Cues were offered alone and no such cue as a control in the same set-up. Sulfuric sediments and dead fish were significantly more attractive to females, and other crabs irrespective of gender were significantly more attractive to males. When compared to expected distributions, crabs, irrespective of gender, significantly avoided light and tended to select other crabs, air-bubbling, sulfuric sediment, elevated temperature, dead fish, dead zooplankton, and quarz sediments in the order of decreasing importance. Data do not support the hypothesis that dead settled zooplankton was particularly attractive nor that the other gender was selected. A combination of several vent-associated cues (sulfuric sediment, elevated temperature, air-bubbling) facilitated the strongest attraction to the crabs as reflected by all response variables. The 'first choice' responses were always consistent with the side of the choice compartment in which they spent the longest amount of time (resident time), but not with the 'final choice' of crabs, suggesting that the 'resident time' in addition to their 'first choice' is more reliable than just the 'final choice'. The present results provide the first indication that several vent-associated habitat cues function as attractors for HV crabs. Habitat choice is also reflected by crab larval distribution in the field which tend to stay near the bottom not to be carried away from their specific habitat.

Adaptive ultrasound temperature imaging for monitoring radiofrequency ablation

Radiofrequency ablation (RFA) has been widely used as an alternative treatment modality for liver tumors. Monitoring the temperature distribution in the tissue during RFA is required to assess the thermal dosage. Ultrasound temperature imaging based on the detection of echo time shifts has received the most attention in the past decade. The coefficient k, connecting the temperature change and the echo time shift, is a medium-dependent parameter used to describe the confounding effects of changes in the speed of sound and thermal expansion as temperature increases. The current algorithm of temperature estimate based on echo time shift detection typically uses a constant k, resulting in estimation errors when ablation temperatures are higher than 50°C. This study proposes an adaptive-k algorithm that enables the automatic adjustment of the coefficient k during ultrasound temperature monitoring of RFA. To verify the proposed algorithm, RFA experiments on in vitro porcine liver samples (total n = 15) were performed using ablation powers of 10, 15, and 20 W. During RFA, a clinical ultrasound system equipped with a 7.5-MHz linear transducer was used to collect backscattered signals for ultrasound temperature imaging using the constant- and adaptive-k algorithms. Concurrently, an infrared imaging system and thermocouples were used to measure surface temperature distribution of the sample and internal ablation temperatures for comparisons with ultrasound estimates. Experimental results demonstrated that the proposed adaptive-k method improved the performance in visualizing the temperature distribution. In particular, the estimation errors were also reduced even when the temperature of the tissue is higher than 50°C. The proposed adaptive-k ultrasound temperature imaging strategy has potential to serve as a thermal dosage evaluation tool for monitoring high-temperature RFA.

Diabetes risks and outcomes in chronic obstructive pulmonary disease patients: Two nationwide population-based retrospective cohort studies

OBJECTIVE

The relationship between chronic obstructive pulmonary disease (COPD) and diabetes remains incompletely understood. This study evaluated diabetes risk and post-diabetes outcomes in COPD patients with and without exacerbations.

METHODS

We identified 4671 adults newly diagnosed with COPD exacerbations and 9342 adults newly diagnosed with COPD without exacerbations during 2000-2008 using Taiwan's National Health Insurance Research Database. A comparison cohort of 18684 adults without COPD, matched by age and sex, was randomly selected from the same dataset for the control group. Diabetes events during 2000-2013 were ascertained from medical claims during the follow-up period. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of diabetes associated with COPD with or without exacerbations were calculated. We conducted another nested cohort study of 395516 patients with diabetes hospitalization during 2002-2013 and calculated adjusted odds ratios (ORs) and 95% CIs of histories of COPD and COPD exacerbations associated with adverse events after diabetes admission.

RESULTS

During the follow-up period, the incidences of diabetes for patients without COPD and for patients with COPD without or with exacerbations were 3.4, 4.1 and 7.4 per 1000 person-years, respectively (P < 0.0001). Increased risk of diabetes for patients with COPD without exacerbations (HR 1.09, 95% CI 1.02-1.17) and COPD with exacerbations (HR 2.18, 95% CI 1.88-2.52) was noted. Post-diabetes pneumonia (OR 3.28, 95% CI 3.13-3.43), intensive care admission (OR 1.32, 95% CI 1.26-1.39) and mortality (OR 2.06, 95% CI 1.88-2.25) were associated with COPD exacerbations.

CONCLUSION

Prevention and intervention strategies for diabetes and post-diabetes outcomes are needed for this susceptible population.

A novel noninvasive surface ECG analysis using interlead QRS dispersion in arrhythmogenic right ventricular cardiomyopathy

Background

This study investigated the feasibility of using the precordial surface ECG lead interlead QRS dispersion (IQRSD) in the identification of abnormal ventricular substrate in arrhythmogenic right ventricular cardiomyopathy (ARVC).

Methods

Seventy-one consecutive patients were enrolled and reclassified into 4 groups: definite ARVC with epicardial ablation (Group 1), ARVC with ventricular tachycardia (VT, Group 2), idiopathic right ventricular outflow tract VT without ARVC (Group 3), and controls without VT (Group 4). IQRSD was quantified by the angular difference between the reconstruction vectors obtained from the QRS-loop decomposition, based on a principal component analysis (PCA). Electroanatomic mapping and simulated ECGs were used to investigate the relationship between QRS dispersion and abnormal substrate.

Results

The percentage of the QRS loop area in the Group 1–2 was smaller than the controls (P = 0.01). The IQRSD between V1-V2 could differentiate all VTs from control (P<0.01). Group 1–2 had a greater IQRSD than the Group 3–4 (V4-V5,P = 0.001), and Group 1 had a greater IQRSD than Group 3–4 (V6-Lead I, P<0.001). Both real and simulated data had a positive correlation between the maximal IQRSD (γ = 0.62) and the extent of corresponding abnormal substrate (γ = 0.71, both P<0.001).

Conclusions

The IQRSD of the surface ECG precordial leads successfully differentiated ARVC from controls, and could be used as a noninvasive marker to identify the abnormal substrate and the status of ARVC patients who can benefit from epicardial ablation.