BACKGROUND: The QT variability index (QTVI)-a non-invasive measure of beat-to-beat QT interval (QTI) fluctuations-is related to myocardial repolarization lability. The QTVI represents the relationship between QTI and the RR interval. Elevated QTVI is associated with an increased risk of malignant ventricular arrhythmias and sudden death. We investigated the influence of general anesthesia and tourniquets on the QTVI. METHODS: We studied fifty patients who received total knee replacement arthroplasty under sevoflurane anesthesia. We measured QTI, corrected QTI (QTc), T-wave peak-to-end interval (TPE), QTVI, and heart rate variability. All variables were calculated at baseline (B), 30 min after general anesthesia (A), 30 min (TQ1) and 60 min (TQ2) after tourniquet inflation, and at tourniquet deflation (TQR). RESULTS: Prolongation of QTI was detected at all times, and QTc was significantly prolonged TQR. TPE was unchanged during general anesthesia. The QTVI was significantly decreased and more negative during anesthesia and tourniquet inflation. After deflation of the tourniquet, the QTVI was restored to preanesthetic values. Low frequency (LF) was significantly decreased during general anesthesia, but high frequency (HF) was somewhat maintained, except at TQ2. The LF/HF ratio was significantly decreased at A and TQ2. CONCLUSIONS: Sevoflurane based general anesthesia induced repolarization stability and, more negativity of the QTVI, in patients undergoing total knee replacement arthroplasty.
Anesthesia ; Anesthesia, General* ; Arrhythmias, Cardiac ; Arthroplasty ; Arthroplasty, Replacement, Knee ; Death, Sudden ; Heart Rate ; Humans ; Inflation, Economic ; Tourniquets

No abstract available.
Humans ; Shoulder* ; Stents* ; Thrombosis*

We assessed empathy in medical residents, including factors modifying empathy and the relationship between empathy and burnout. Participants (n = 317 residents, response rate = 42%) from 4 university hospitals completed a socio-demographic questionnaire, the Jefferson Scale of Empathy (Health Professional version, Korean edition), and the Maslach Burnout Inventory (MBI). Participants were classified by medical specialty: “people-oriented specialty” (POS group) or “technology-oriented specialty” (TOS group), with more women in the POS than in the TOS group, χ2 = 14.12, P < 0.001. Being female, married, and having children were factors related to higher empathy (gender, t = -2.129, P = 0.034; marriage, t = -2.078, P = 0.038; children, t = 2.86, P = 0.005). Within specialty group, POS residents showed higher empathy scores in the fourth as compared to the first year, F = 3.166, P = 0.026. Comparing POS and TOS groups by year, fourth year POS residents had significantly higher scores than did fourth year TOS residents, t = 3.349, P = 0.002. There were negative correlations between empathy scores and 2 MBI subscales, emotional exhaustion (EE) and depersonalization (DP). Additionally, first year POS residents had higher DP scores than did first year TOS residents, t = 2.183, P = 0.031. We suggest that factors important for empathy are type of medical specialty, marriage, siblings, and children. Burnout state may be related to decreasing empathy.
Adult ; *Burnout, Professional ; Child ; Child Rearing ; Demography ; Depersonalization ; *Empathy ; Female ; Hospitals, University ; Humans ; Internship and Residency ; Male ; Marriage ; Physicians/*psychology ; Sex Factors ; Surveys and Questionnaires

In the ‘Acknowledgements’ section on page 263 of the original article, the grant number was incorrectly stated.

OBJECTIVE: Empathy is important in the education of medical students. Many psychosocial variables are related to empathy. The aim of the study was to investigate the relationship between empathy and psychosocial factors such as burnout, personality, self-esteem, and resilience. METHODS: The participants completed a set of self-reporting questionnaires, including questions related to socio-demographic characteristics, the Korean edition of the Jefferson Scale of Empathy, student version (JSE-S-K), Maslach Burnout Inventory General Survey (MBI-GS), NEO Five-Factor Inventory (NEO-FFI), Rosenberg Self-esteem Scale (R-SES), and Connor-Davidson Resilience Scale (CD-RISC). Partial correlation and regression analyses were performed. RESULTS: In male students, there were positive correlations between JSE-S-K and R-SES (r=0.229, p=0.002); conscientiousness of the NEO-FFI (r=0.153, p=0.037) and negative correlations, specifically between JSE-S-K and depersonalization of MBI (r=-0.206, p=0.005). In female students, there was positive correlations between JSE-S-K and personal accomplishment of MBI (r=0.384, p=0.004). In the multiple regression model, the JSE-S-K was affected by conscientiousness of the NEO-FFI (adjusted R² =0.245, β=0.201, p=0.001); depersonalization, personal accomplishment of the MBI-GS (β=-0.188, p=0.001, β=0.143, p=0.017); R-SES (β=0.176, p=0.004); sex (β=0.117, p=0.029). CONCLUSION: The present findings suggested that conscientiousness, depersonalization, personal accomplishment, self-esteem and sex have an influence on empathy. Therefore, these must be considered in medical education and can be helpful to nurture more empathetic doctors.
Cross-Sectional Studies ; Depersonalization ; Education ; Education, Medical ; Empathy ; Female ; Humans ; Male ; Psychology ; Students, Medical

Background: This study reports trends in pediatric out-of-hospital cardiac arrest (OHCA) and factors affecting clinical outcomes by age group. Methods: We identified 4,561 OHCA patients younger than 18 years between January 2009 and December 2018 in the Korean OHCA Registry. The patients were divided into four groups: group 1 (1 year or younger), group 2 (1 to 5 years), group 3 (6 to 12 years), and group 4 (13 to 17 years). The primary outcome was survival to hospital discharge, and the secondary outcomes were return of spontaneous circulation (ROSC) at the emergency department (ED) and good neurological status at discharge. Multivariate logistic analyses were performed. Results: The incidence rate of pediatric OHCA in group 1 increased from 45.57 to 60.89 per 100,000 person-years, while that of the overall population decreased over the 10 years. The rates of ROSC at the ED, survival to hospital discharge, and good neurologic outcome were highest in group 4 (37.9%, 9.7%, 4.9%, respectively) and lowest in group 1 (28.3%, 7.1%, 3.2%). The positive factors for survival to discharge were event location of a public/commercial building or place of recreation, type of first responder, prehospital delivery of automated external defibrillator shock, initial shockable rhythm at the ED. The factors affecting survival outcomes differed by age group. Conclusion This study reports comprehensive trends in pediatric OHCA in the Republic of Korea. Our findings imply that preventive methods for the targeted population should be customized by age group.

Purpose: Thrombotic stroke is a type of ischemic stroke characterized by motor dysfunction and memory impairments. In the present study, the effect of treadmill exercise on motor function and short-term memory was evaluated in relation with synaptic plasticity in the mice with photothrombotic stroke. Methods: Photothrombotic stroke was induced by cortical photothrombotic vascular occlusion. The mice in the treadmill exercise groups performed running on a motorized treadmill for 28 days. Motor function was determined using rota-rod test and foot fault test. Step-through avoidance task was conducted to evaluate short-term memory. Immunohistochemistry for 5-bromo-2′-deoxyuridine and doublecortin was conducted to detect new cell generation. Postsynaptic density protein 95, synaptophysin, brain-derived neurotrophic factor (BDNF), and tyrosine kinase B receptor (TrkB) were determined using western blot. The number of dendritic spines was determined using Golgi stain. Results: Treadmill exercise improved motor function and short-term memory in mice with the photothrombotic stroke. The infarct size was reduced and the number of dendritic spines and expression of postsynaptic density protein 95 and synaptophysin in the peri-infarct cortex and hippocampus were increased by treadmill exercise in photothrombotic stroke mice. Treadmill exercise enhanced neurogenesis through increasing the expression of the hippocampal BDNF and TrkB in photothrombotic stroke mice. Conclusions Treadmill exercise improved motor function and short-term memory through increasing synaptic plasticity and neurogenesis in photothrombotic stroke mice. Treadmill exercise can be used as an effective treatment strategy to improve brain function related to stroke.

A substantial proportion of patients with autism spectrum disorder (ASD) display hyperactivity as a comorbid symptom. Exposure to valproic acid (VPA) during pregnancy produces ASD-like core behavioral phenotypes as well as hyperactivity in offspring both in human and experimental animals, which makes it a plausible model to study ASD-related neurobiological processes. In this study, we examined the effects of two of currently available attention defecit hyperactivity disorder (ADHD) medications, methylphenidate (MPH) and atomoxetine (ATX) targeting dopamine and norepinephrine transporters (DAT and NET), respectively, on hyperactive behavior of prenatally VPA-exposed rat offspring. In the prefrontal cortex of VPA exposed rat offspring, both mRNA and protein expression of DAT was increased as compared with control. VPA function as a histone deacetylase inhibitor (HDACi) and chromatin immunoprecipitation experiments demonstrated that the acetylation of histone bound to DAT gene promoter was increased in VPA-exposed rat offspring suggesting epigenetic mechanism of DAT regulation. Similarly, the expression of NET was increased, possibly via increased histone acetylation in prefrontal cortex of VPA-exposed rat offspring. When we treated the VPA-exposed rat offspring with ATX, a NET selective inhibitor, hyperactivity was reversed to control level. In contrast, MPH that inhibits both DAT and NET, did not produce inhibitory effects against hyperactivity. The results suggest that NET abnormalities may underlie the hyperactive phenotype in VPA animal model of ASD. Profiling the pharmacological responsiveness as well as investigating underlying mechanism in multiple models of ASD and ADHD may provide more insights into the neurobiological correlates regulating the behavioral abnormalities.
Acetylation ; Animals ; Autistic Disorder ; Child ; Autism Spectrum Disorder ; Chromatin Immunoprecipitation ; Dopamine ; Epigenomics ; Histone Deacetylase Inhibitors ; Histones ; Humans ; Methylphenidate ; Models, Animal ; Norepinephrine ; Norepinephrine Plasma Membrane Transport Proteins ; Phenotype ; Prefrontal Cortex ; Pregnancy ; Rats* ; RNA, Messenger ; Valproic Acid ; Atomoxetine Hydrochloride

The valproic acid (VPA)-induced animal model is one of the most widely utilized environmental risk factor models of autism. Autism spectrum disorder (ASD) remains an insurmountable challenge among neurodevelopmental disorders due to its heterogeneity, unresolved pathological pathways and lack of treatment. We previously reported that VPA-exposed rats and cultured rat primary neurons have increased Pax6 expression during post-midterm embryonic development which led to the sequential upregulation of glutamatergic neuronal markers. In this study, we provide experimental evidence that telomerase reverse transcriptase (TERT), a protein component of ribonucleoproteins complex of telomerase, is involved in the abnormal components caused by VPA in addition to Pax6 and its downstream signals. In embryonic rat brains and cultured rat primary neural progenitor cells (NPCs), VPA induced the increased expression of TERT as revealed by Western blot, RT-PCR, and immunostainings. The HDAC inhibitor property of VPA is responsible for the TERT upregulation. Chromatin immunoprecipitation revealed that VPA increased the histone acetylation but blocked the HDAC1 binding to both Pax6 and Tert genes. Interestingly, the VPA-induced TERT overexpression resulted to sequential upregulations of glutamatergic markers such as Ngn2 and NeuroD1, and inter-synaptic markers such as PSD-95, α-CaMKII, vGluT1 and synaptophysin. Transfection of Tert siRNA reversed the effects of VPA in cultured NPCs confirming the direct involvement of TERT in the expression of those markers. This study suggests the involvement of TERT in the VPA-induced autistic phenotypes and has important implications for the role of TERT as a modulator of balanced neuronal development and transmission in the brain.
Acetylation ; Animals ; Autism Spectrum Disorder ; Autistic Disorder ; Blotting, Western ; Brain ; Chromatin Immunoprecipitation ; Embryonic Development ; Female ; Histones ; Models, Animal ; Neurodevelopmental Disorders ; Neurons ; Phenotype ; Population Characteristics ; Pregnancy ; Rats ; Ribonucleoproteins ; Risk Factors ; RNA, Small Interfering ; Stem Cells ; Synaptophysin ; Telomerase* ; Transfection ; Up-Regulation ; Valproic Acid*