In Situ Photo-Crosslinkable Protein Bioadhesive for Bone Graft Fixation

Bone grafting is a fundamental dental surgery procedure widely used for implant placement and periodontal disease management treatments. Despite its broad applications, vertical bone augmentation presents unique challenges, including the risk of graft displacement due to gravitational and masticatory forces. Traditional physical stabilization methods introduce additional complexities and risks, underscoring the need for innovative fixation technologies. This study aimed to develop an in situ photo-crosslinkable bioadhesive hydrogel (iPBAH) as a multifunctional bone graft binder to enhance the process of bone reconstruction. The bioadhesive is composed of mussel-derived adhesive protein (MAP) fused with the cell-adhesive peptide RGD. The numerous tyrosine residues in MAP facilitate rapid photo-crosslinking, enabling efficient hydrogel formation using visible blue light. Subsequently, iPBAH underwent comprehensive characterization to evaluate its suitability as a multifunctional bone graft binder. iPBAH efficiently underwent in situ crosslinking through harmless exposure to visible light within minutes and displayed several exceptional properties, including a microporous structure, underwater adhesion, extended durability, high compressive strength, and biocompatibility. In vivo assessments, using male Sprague-Dawley rats, demonstrated that iPBAH binder significantly enhanced bone regeneration in a rat calvarial bone defect model. The in situ crosslinking of the iPBAH binder during bone graft transplantation can effectively fill irregular and complex defect shapes while simultaneously preventing graft material leakage. The improved physical attributes of the bound graft material can enhance its resistance to external forces, thereby ensuring sustained retention over time. Moreover, the interaction between iPBAH and surrounding tissues promotes adhesion and integration of the graft material with host tissues in the defect area. In addition, the included RGD peptide in iPBAH can augment inherent cell recruitment, adhesion, and growth, consequently expediting osteogenesis.

Open-top Bessel beam two-photon light sheet microscopy for three-dimensional pathology

Nondestructive pathology based on three-dimensional (3D) optical microscopy holds promise as a complement to traditional destructive hematoxylin and eosin (H&E) stained slide-based pathology by providing cellular information in high throughput manner. However, conventional techniques provided superficial information only due to shallow imaging depths. Herein, we developed open-top two-photon light sheet microscopy (OT-TP-LSM) for intraoperative 3D pathology. An extended depth of field two-photon excitation light sheet was generated by scanning a nondiffractive Bessel beam, and selective planar imaging was conducted with cameras at 400 frames/s max during the lateral translation of tissue specimens. Intrinsic second harmonic generation was collected for additional extracellular matrix (ECM) visualization. OT-TP-LSM was tested in various human cancer specimens including skin, pancreas, and prostate. High imaging depths were achieved owing to long excitation wavelengths and long wavelength fluorophores. 3D visualization of both cells and ECM enhanced the ability of cancer detection. Furthermore, an unsupervised deep learning network was employed for the style transfer of OT-TP-LSM images to virtual H&E images. The virtual H&E images exhibited comparable histological characteristics to real ones. OT-TP-LSM may have the potential for histopathological examination in surgical and biopsy applications by rapidly providing 3D information.

Disparity in the dental care of children and adolescents with autism spectrum disorder in Korea: a national population-based cross-sectional study

Individuals with autism spectrum disorders (ASD) have difficulty accessing dental care. We aim to verify whether individuals with ASD are properly managed by checking the frequency of dental visits, cost and severity of dental treatment compared with those without ASD. This cross-sectional study used the Korean Health Insurance Database to analyze the frequency, cost and severity of dental treatment in 209,780 people under the age of 19 with or without ASD in 2020. The average frequency of dental visits for individuals without ASD was 2.98 times, which was significantly higher (p < 0.001) than the 2.89 times for those with ASD. However, the average dental cost for individuals with ASD was USD 132.63, which was significantly higher (p < 0.001) than USD 116.57 for those without ASD. Additionally, the average number of times that individuals without ASD received severe dental treatment was 1.23 times, significantly higher than the 1.15 times for those with ASD. Further, per 10,000 people, we found that trauma treatment was recorded for an average of 21.90 individuals with ASD, significantly higher than the 7.75 recorded for those without ASD (p < 0.001). Individuals with ASD encounter significant disparities in accessing dental care, as evidenced by their relatively infrequent dental visits. This discrepancy can be attributed to various barriers including the financial burden compared with those without ASD.

Approval status of essential therapeutic drugs for systemic sclerosis versus that of drugs for rheumatoid arthritis

Objective

Systemic sclerosis, a rare disease characterized by chronic multisystem fibrosis, requires lifelong management, necessitating enough insurance coverage for the patient. Official drug approval is the first step to ensuring that the drug is covered by insurance. In this study, we investigated the approval status of essential therapeutic drugs for systemic sclerosis across eight countries and compared it with that of drugs for rheumatoid arthritis.

Methods

The essential therapeutic drug lists for systemic sclerosis and rheumatoid arthritis were taken from the guidelines of the American College of Rheumatology and the European Alliance of Associations for Rheumatology. Official drug approval status for the selected drugs was confirmed by searching representative Internet databases from eight countries: the United States, the United Kingdom, Germany, France, Italy, Switzerland, Japan, and the Republic of Korea.

Results

A total of 21 and 16 drugs were selected for systemic sclerosis and rheumatoid arthritis, respectively. The drug approval rates of the 21 drugs for systemic sclerosis varied among countries. Most drugs used to treat pulmonary arterial hypertension, which were developed recently and are expensive, are approved by most countries; however, most older drugs-which are still essential for management of Raynaud's phenomenon, digital ulcers, interstitial lung disease, and skin fibrosis-are not approved by most countries. By contrast, almost all of the 16 drugs used to treat rheumatoid arthritis, whether old or new, are approved by most countries.

Conclusion

Approval rates for drugs used to treat systemic sclerosis, a rare disease, are much lower than those for drugs used to treat rheumatoid arthritis. Thus, approval rates of essential therapeutic drugs for systemic sclerosis need to improve, which will benefit patients by increasing the number of drugs covered by insurance.

Immature bovine cartilage wear is due to fatigue failure from repetitive compressive forces and not reciprocating frictional forces

OBJECTIVE

Wear of articular cartilage is not well understood. We hypothesize that cartilage wears due to fatigue failure in repetitive compression instead of reciprocating friction.

DESIGN

This study compares reciprocating sliding of immature bovine articular cartilage against glass in two testing configurations: (1) a stationary contact area configuration (SCA), which results in static compression, interstitial fluid depressurization, and increasing friction coefficient during reciprocating sliding, and (2) a migrating contact area configuration (MCA), which maintains pressurization and low friction while producing repetitive compressive loading in addition to reciprocating sliding. Contact pressure, sliding duration, and sliding distance were controlled to be similar between test groups.

RESULTS

SCA tests exhibited an average friction coefficient of μ=0.084±0.032, while MCA tests exhibited a lower average friction coefficient of μ=0.020±0.008 (p<10-4). Despite the lower friction, MCA cartilage samples exhibited clear surface damage with a significantly greater average surface deviation from a fitted plane after wear testing (Rq=0.125±0.095 mm) than cartilage samples slid in a SCA configuration (Rq=0.044±0.017 mm, p=0.002), which showed minimal signs of wear. Polarized light microscopy confirmed that delamination damage occurred between the superficial and middle zones of the articular cartilage in MCA samples.

CONCLUSIONS

The greatest wear was observed in the group with lowest friction coefficient, subjected to cyclical instead of static compression, implying that friction is not the primary driver of cartilage wear. Delamination between superficial and middle zones implies the main mode of wear is fatigue failure under cyclical compression, not fatigue or abrasion due to reciprocating frictional sliding.

Prevalence and severity of COVID-19 among children and adolescents with autism spectrum disorders in the Republic of Korea

LAY ABSTRACT

It is more difficult to prevent coronavirus disease 2019 in children and adolescents with autism spectrum disorder, as they have trouble communicating and adjusting to their new daily lives like wearing masks and social distancing. However, there have not been many studies that focused on coronavirus disease 2019 among children and adolescents with autism spectrum disorder. We included all Korean citizens under the age of 19 as our study subjects. Among them, we found out the prevalence, severity, and case fatality of coronavirus disease 2019 in children and adolescents with and without autism spectrum disorder. The prevalence of coronavirus disease 2019 among children and adolescents with autism spectrum disorder was lower than that of those without autism spectrum disorder. For severity, children and adolescents with autism spectrum disorder were more likely to enter severe stages of disease and had higher hospitalization rates than those without autism spectrum disorder. There were no deaths among children and adolescents with autism spectrum disorder, while a few died among children and adolescents without autism spectrum disorder. However, due to the small number of deaths, it was difficult to determine whether there was a link between autism spectrum disorder and coronavirus disease 2019 deaths. We found that the appropriate quarantine policies have played a great role in sustaining overall low prevalence and higher hospitalization rates among children and adolescents with autism spectrum disorder than those without autism spectrum disorder. Furthermore, because Korea has fewer schools and facilities (i.e. personal care, social training, and skilled nursing facility) for children and adolescents with autism spectrum disorder than other countries, those with autism spectrum disorder have fewer social contacts than even before the COVID-19 pandemic.

Significance of Radiomics in Predicting Local Control for Patients with Malignant Liver Tumors Treated Using Stereotactic Body Radiotherapy

PURPOSE/OBJECTIVE(S)

We routinely deliver Stereotactic Body Radiotherapy (SBRT) in malignant liver tumors using planning computed tomography (CT) and Magnetic Resonance Images (MRI) to aid target definition. In this study, we extracted radiomic features from the MR images to predict local control (LC) post-SBRT.

MATERIALS/METHODS

We retrospectively analyzed patients with either hepatocellular cancers (HCCs) or liver metastases (Mets) treated with SBRT between Aug 2014 and Aug 2020. All patients had CT simulation followed by 1.5 Tesla planning MRI in treatment position. Contrast enhanced T1 VIBE and T2 Haste MR sequences were registered with planning CT for target definition. Radiomic features were extracted from Gross Tumor Volumes (GTV) masked out of 60 seconds post contrast T1 VIBE MR images using the Radiomics calculator tool RaCaT. The output included 480 (408 textural, 50 intensity and 22 morphological) features for each target. Principal Component Analysis of the outputs obtained from all the targets yielded 20 radiomic feature clusters after computational prioritization. These clusters were correlated to LC outcomes at various time points post-SBRT. LC was defined as non-progressive disease. Accuracy of predictions was measured by area under (AUC) receiver operating characteristic curve. Cox regression analysis was done to find univariate and multivariate clinical [HCCs vs. Mets, single vs. multiple lesions, previous local therapy (yes vs. no), GTV volume (≤40 vs. >40 cc)], radiomic and dosimetric predictors (continuous) of LC.

RESULTS

In total, 97 patients received SBRT to 122 lesions. The median dose prescribed was 45 Gy (range, 30-50 Gy). Median age was 69 years (interquartile range, IQR 61-73 yrs.). 59 patients had HCCs and 38 had Mets. 24 lesions had prior ablative therapy. 75 patients had one target, and 22 had multiple targets. Median GTV was 43.5 cc (IQR 23.4-78.6 cc). Median follow up was 16.6 months (IQR 9.7-27.2 mths). Median LC was 13.6 months (IQR 8.0-23.5 mths). On univariate analysis, histology (HCCs vs. Mets; Hazard ratio (HR) 2.9, 95% CI 1.4-6.4; p < 0.006), radiomic clusters (p < 0.006) and the max., mean, and min. doses to GTV and Planning Target Volumes correlated with improved LC (all p-values < 0.05). On multivariate analysis, histology (HCCs vs. Mets; HR 4.4, 95% CI 1.6-12.3; p = 0.004), radiomic clusters (p = 0.034) and prescription dose (p = 0.048) were significant covariates. Specifically, the 20 radiomic clusters were predictive of LC, and the accuracy of predictions showed promise with AUC values of 0.74, 0.80, and 0.81 at 12, 24, and 36 months post-SBRT, respectively. AUC values for LC in HCCs vs. Mets at 12, 24, and 36 months were 0.83, 0.77, and 0.70, and 0.66, 0.77, and 0.88, respectively.

CONCLUSION

MR-based radiomics predict LC post-SBRT in patients with malignant liver tumors. Further research focused on independent validation of the model is required to explore its clinical use.

MicroRNA 29a therapy for CEACAM6-expressing lung adenocarcinoma

BACKGROUND

Non-coding microRNAs (miRNAs) play critical roles in tumor progression and hold great promise as therapeutic agents for multiple cancers. MicroRNA 29a (miR-29a) is a tumor suppressor miRNA that inhibits cancer cell growth and tumor progression in non-small cell lung cancer. Carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6), which plays an important role in lung cancer progression, has been identified as a target of miR-29a. Here, we evaluated the therapeutic efficacy of a peptide vector capable of delivering miR-29a intracellularly using the acidic tumor microenvironment in a lung adenocarcinoma xenograft mouse model.

METHODS

A miRNA delivery vector was constructed by tethering the peptide nucleic acid form of miR-29a to a peptide with a low pH-induced transmembrane structure (pHLIP) to enable transport of the miRNAs across the plasma membrane. Tumor suppressive effects of pHLIP-miR29a on lung adenocarcinoma development in vivo were assessed using a BALB/c xenograft model injected with A549 cells.

RESULTS

Incubation of A549 cells with pHLIP-miR-29a at an acidic pH downregulated endogenous CEACAM6 expression and reduced cell viability. Intravenous injection of the mice with pHLIP-miR-29a inhibited tumor growth by up to 18.1%. Intraperitoneal injection of cisplatin reduced tumor volume by 29.9%. Combined pHLIP-miR-29a + cisplatin treatment had an additive effect, reducing tumor volume up to 39.7%.

CONCLUSIONS

Delivery of miR-29a to lung adenocarcinoma cells using a pHLIP-mediated method has therapeutic potential as a unique cancer treatment approach.

Deep Learning of Time-Signal Intensity Curves from Dynamic Susceptibility Contrast Imaging Enables Tissue Labeling and Prediction of Survival in Glioblastoma

BACKGROUND AND PURPOSE

An autoencoder can learn representative time-signal intensity patterns to provide tissue heterogeneity measures using dynamic susceptibility contrast MR imaging. The aim of this study was to investigate whether such an autoencoder-based pattern analysis could provide interpretable tissue labeling and prognostic value in isocitrate dehydrogenase (IDH) wild-type glioblastoma.

MATERIALS AND METHODS

Preoperative dynamic susceptibility contrast MR images were obtained from 272 patients with IDH wild-type glioblastoma (training and validation, 183 and 89 patients, respectively). The autoencoder was applied to the dynamic susceptibility contrast MR imaging time-signal intensity curves of tumor and peritumoral areas. Representative perfusion patterns were defined by voxelwise K-means clustering using autoencoder latent features. Perfusion patterns were labeled by comparing parameters with anatomic reference tissues for baseline, signal drop, and percentage recovery. In the validation set (n = 89), a survival model was created from representative patterns and clinical predictors using Cox proportional hazard regression analysis, and its performance was calculated using the Harrell C-index.

RESULTS

Eighty-nine patients were enrolled. Five representative perfusion patterns were used to characterize tissues as high angiogenic tumor, low angiogenic/cellular tumor, perinecrotic lesion, infiltrated edema, and vasogenic edema. Of these, the low angiogenic/cellular tumor (hazard ratio, 2.18; P = .047) and infiltrated edema patterns (hazard ratio, 1.88; P = .009) in peritumoral areas showed significant prognostic value. The combined perfusion patterns and clinical predictors (C-index, 0.72) improved prognostication when added to clinical predictors (C-index, 0.55).

CONCLUSIONS

The autoencoder perfusion pattern analysis enabled tissue characterization of peritumoral areas, providing heterogeneity and dynamic information that may provide useful prognostic information in IDH wild-type glioblastoma.

[The status and influencing factors of presenteeism among clinical nurses: a systematic review]

Objective: To systematically review the status and factors influencing presenteeism among clinical nurses. Methods: In December 2021, CNKI, CBM, Wanfang, VIP, Web of Science, PubMed, Embase, The Cochrane Library, CINAHL, PsyclNFO and other databases were electronically searched to cross sectional studies on the current situation and factors influencing the occurrence of presenteeism among clinical nurses. The search terms mainly included presenteeism, sick at work, Stanford Presenteeism Scale, nurse, level, risk factor, influence, et al. And the search time was from the establishment of the database to November 30, 2021. Literature screening, data extraction and evaluation of the risk of bias in the included literature were done independently by two researchers, and meta-analysis was performed using Stata 15.1 software. Results: A total of 29 studies involving 13 535 clinical nurses were included.The results of the meta-analysis showed that the score of presenteeism was 17.99 [95% CI (17.02-18.95), P =0.000]. Subgroup analysis showed that presenteeism scores were higher in articles published before 2020 (ES=19.28, 95%CI: 18.41-20.15, P=0.000) and in the group of nurses aged 36 to 40 years (ES=19.27, 95%CI: 17.35~21.19, P=0.000), female (ES= 17.04, 95%CI: 14.70-19.39, P=0.000), secondary school education (ES=21.01, 95%CI: 17.76-24.26, P= 0.007), married (ES=17.49, 95%CI: 15.13-19.85, P=0.000), working for 5 to 10 years (ES=17.78, 95%CI: 16.54-19.02, P=0.000), contract (ES=17.05, 95%CI: 15.23-18.87, P=0.000), working in pediatrics (ES= 16.65, 95% CI: 15.31-17.99, P=0.000) and European region (ES =21.21, 95% CI: 20.50-21.93, P=0.000) . Conclusion: Current evidence suggests that clinical nurses are at high risk of presenteeism, which is affected by variety of factors. The managers should pay attention to the physical and mental health of nurses, identify high-risk factors as early as possible and take measures to reduce the occurrence of presenteeism and improve the quality of nursing.

Gold single-atoms confined at the CeOx-TiO2interfaces with enhanced low-temperature activity toward CO oxidation

We use CeO_x-TiO₂hetero-interfaces generated on the surface of CeO_x-TiO₂hybrid oxide supporting powders to stabilize Au single-atoms (SAs) with excellent low-temperature activity toward CO oxidation. Based on intriguing density functional theory calculation results on the preferential formation of Au-SAs at the CeO_x-TiO₂interfaces and the high activity of Au-SAs toward the Mars-van Krevelen type CO oxidation, we synthesized a Au/CeO_x-TiO₂(ACT) catalyst with 0.05 wt.% of Au content. The Au-SAs stabilized at the CeO_x-TiO₂interfaces by electronic coupling between Au and Ce showed improved low-temperature CO oxidation activity than the conventional Au/TiO₂control group catalyst. However, the light-off profile of ACT showed that the early activated Au-SAs are not vigorously participating in CO oxidation. The large portion of the positive effect on the overall catalytic activity from the low activation energy barrier of ACT was retarded by the negative impact from the decreasing active site density at high temperatures. We anticipate that the low-temperature activity and high-temperature stability of Au-SAs that stand against each other can be optimized by controlling the electronic coupling strength between Au-SAs and oxide clusters at the Au-oxide-TiO₂interfaces. Our results show that atomic-precision interface modulation could fine-tune the catalytic activity and stability of Au-SAs.

Incidence and predictors of transthyretin cardiac amyloidosis in patients with degenerative aortic stenosis

Background

The approval of new therapies for treating transthyretin (TTR) cardiac amyloidosis has led to significant interest in identifying patients at high risk for this disease. Investigators have identified a correlation between severe degenerative aortic stenosis (AS) and TTR cardiac amyloidosis in older patients, with several studies finding up to 20% of patients who undergo transcatheter aortic valve replacement (TAVR) having TTR cardiac amyloidosis. These initial TAVR studies were conducted when TAVR was performed almost exclusively in high surgical risk populations. Therefore, the true incidence of TTR cardiac amyloidosis in an all-comers with severe degenerative AS referred for TAVR is unknown.

Purpose

To identify the true burden of TTR cardiac amyloidosis in a contemporary population of severe degenerative AS undergoing TAVR screening.

Methods

All patients ≥70 years with severe native valve degenerative AS seen in a multidisciplinary valve clinic were referred for technetium-99m pyrophosphate cardiac scintigraphy (PYP scan) for evaluation of cardiac amyloidosis. Diagnosis was made via combination of planar grade and heart to contralateral lung ratio, confirmed on single positron emission computed tomography/computed tomography (SPECT/CT). Patients with a positive PYP scan were referred to a heart failure clinic where they underwent testing for AL amyloidosis.

Results

Over a 10 month period, 247 patients seen in valve clinic underwent a PYP scan. Of this cohort, 203 patients ultimately underwent TAVR, 15 surgical aortic valve replacement, and 2 balloon valvuloplasty with 27 patients having not yet undergone a procedure. The positivity rate was 4% (10/247) with 1 patient having an equivocal result. The patients with a positive PYP scan had higher rate of low-flow low-gradient (LFLG) AS (64% vs 29%, p=0.006) and classical LFLG AS (27% vs 8%, p=0.02). Echocardiographic measures associated with a positive PYP scan include a lower global longitudinal strain (−10.0% vs −16.1%, p=0.008), lower average e' (4.5 vs 6.5, p=0.003), and an increased E/A ratio (1.8 vs 1.1, p=0.018).

Conclusions

The incidence of TTR amyloidosis in a contemporary, severe AS population ≥70 years undergoing TAVR screening appears much lower than previously described in the literature. Echocardiographic traits may be able to predict which patients with severe AS should undergo evaluation for TTR cardiac amyloidosis.

Funding Acknowledgement

Type of funding sources: None.

The impact of the COVID-19 pandemic in the healthcare utilization in Korea: Analysis of a nationwide survey

BACKGROUND

COVID-19 has brought changes in daily life and increased the medical burden. This study aims to evaluate the delays in healthcare services and related factors in the general population during the COVID-19 pandemic.

METHODS

We took a nationally representative sample and conducted a mobile phone-based survey. The study was conducted anonymously. Of the 3377 subjects who consented to participate, a total of 2097 finished the survey. The primary outcome was respondents' experiences with delayed (1) health screenings, (2) non-urgent medical visits, (3) medical visits for chronic disease, and (4) emergency visits during the COVID-19 pandemic.

RESULTS

Of 2097 respondents, females, residents of the Seoul metropolitan area, those with private insurance, those without chronic diseases, smokers, and drinkers had higher risk of delays in health screening and non-urgent medical visits after adjustment. Among chronic disease patients, those who were over 60 years old (adjusted odds ratio 0.36, 95% CI 0.14-0.92) showed lower risk of delayed medical visit. Residents of the Seoul metropolitan area, those with private insurance, smokers, and drinkers were all associated with experiencing delayed health screening and non-urgent medical visits had higher risk of delays in chronic disease visits and emergent medical visits.

CONCLUSIONS

Delayed access to healthcare services is associated with poor outcomes and may cause different complications. Efforts are needed to prevent delays in medical use due to infectious diseases such as COVID-19. Considering the possibility of the emergence of infectious diseases, various countermeasures are needed to prevent delays in medical visit.

Interspersing CeOx Clusters to the Pt-TiO2 Interfaces for Catalytic Promotion of TiO2-Supported Pt Nanoparticles

We propose an interface-engineered oxide-supported Pt nanoparticle-based catalyst with improved low-temperature activity toward CO oxidation. By wet-impregnating 1 wt % Ce on TiO₂, we synthesized hybrid oxide support of CeO_x-TiO₂, in which dense CeO_x clusters formed on the surface of TiO₂. Then, the Pt/CeO_x-TiO₂ catalyst was synthesized by impregnating 2 wt % Pt on the CeO_x-TiO₂ supporting oxide. Pt-CeO_x-TiO₂ triphase interfaces were eventually formed upon impregnation of Pt on CeO_x-TiO₂. The Pt-CeO_x-TiO₂ interfaces open up the interface-mediated Mars-van Krevelen CO oxidation pathway, thus providing additional interfacial reaction sites for CO oxidation. Consequently, the specific reaction rate of Pt/CeO_x-TiO₂ for CO oxidation was increased by 3.2 times compared with that of Pt/TiO₂ at 140 °C. Our results demonstrate a widely applicable and straightforward method of catalytic activation of the interfaces between metal nanoparticles and supporting oxides, which enabled fine-tuning of the catalytic performance of oxide-supported metal nanoparticle classes of heterogeneous catalysts.

General public’s perspectives on telemedicine during the COVID-19 pandemic in Korea: an analysis of the nationwide survey

OBJECTIVES

We investigated the awareness, experience, approval, intention to use, and the desired type of telemedicine among Korean general public.

METHODS

From November to December 2020, we conducted an online self-reported survey on awareness, experience, approval, and intent to use telemedicine services among Korean residents aged 20 years or older. A total of 2,097 participants completed the survey.

RESULTS

Of the 2,097 participants, 1,558 (74.3%) were aware of, 1,198 (57.1%) approved of, and 1,474 (70.3%) had the intention to use telemedicine. Participants from regions other than the Seoul metropolitan area and Daegu–Gyeongbuk Province (adjusted odds ratio [aOR], 1.29; 95% confidence interval [CI], 1.02 to 1.63), households with a monthly household income of US$6,000 or more (aOR, 1.44; 95% CI, 1.01 to 2.08), participants who had a college/university or associate’s degree (aOR, 1.35. 95% CI, 1.04 to 1.75) or a master’s degree or above (aOR, 1.73; 95% CI, 1.20 to 2.50), and housewives (aOR, 1.30; 95% CI, 1.03 to 1.64) had higher odds of approval. Elderly participants, those with a chronic disease (aOR, 1.26; 95% CI, 1.04 to 1.54), those who had experienced delays of healthcare services (aOR, 1.94; 95% CI, 1.27 to 2.96), and those who had experience with telemedicine (aOR, 4.28; 95% CI, 1.69 to 10.82) were more likely to intend to use telemedicine services. Regarding types of telemedicine, teleconsultation between doctors showed the highest approval rate (73.1%).

CONCLUSIONS

In the context of the coronavirus disease 2019 pandemic, more than 70% of participants had already used or intended to use telemedicine at some point. Groups with a substantial need for telemedicine were more in favor of telemedicine.

Prevalence and Premature Mortality Statistics of Autism Spectrum Disorder Among Children in Korea: A Nationwide Population-Based Birth Cohort Study

BACKGROUND

The aim of this study was to estimate the 8-year prevalence and mortality statistics of autism spectrum disorder (ASD) according to birth year (2002-2012).

METHODS

We used the National Health Insurance Service database with 4,989,351 children born from 2002 to 2012 including 35,529 children diagnosed with ASD until 8 years of age. The 8-year cumulative prevalence of ASD was calculated annually (2010-2020) with 8 years of follow-up. The 8-year mortality was estimated using Cox models adjusted for sex, household income, area of residence, and year of birth.

RESULTS

Of the 473,494 children born in 2002, 2,467 (5.2 per 1,000 births) were diagnosed with ASD until 2010. The ASD prevalence was 2.6 times higher among boys (1,839; 7.4 per 1,000 boy births) than girls (628; 2.8 per 1,000 girl births). Of the 467,360 children born in 2012, 4,378 (9.4 per 1,000 births) were diagnosed with ASD until 2020. The ASD prevalence was 2.7 times higher among boys (3,246; 13.5 per 1,000 boy births) than girls (1,132; 5.0 per 1,000 girl births). The risk of all-cause mortality was higher among children with ASD than those without (hazard ratio [HR], 2.340; 95% confidence interval [CI], 2.063-2.654), which is substantially higher among girls (HR, 4.223; 95% CI, 3.472-5.135) than boys (HR, 1.774; 95% CI, 1.505-2.090).

CONCLUSION

The present study demonstrated that national-level prevalence and mortality statistics of ASD can be estimated effectively using claims data comprising newborns born each year and followed up for to the age of interest. Because this information is essential to establish evidence-based policies, health authorities need to consider producing epidemiological information of ASD continuously using the same methodology.

Impact of the COVID-19 Pandemic on the Health Status and Behaviors of Adults in Korea: National Cross-sectional Web-Based Self-report Survey

Background

The COVID-19 pandemic has radically shifted living practices, thereby influencing changes in the health status and behaviors of every person.

Objective

The aim of this study was to investigate the impact of COVID-19 on the self-reported health status and health behaviors along with any associated factors in adults in the Republic of Korea wherein no stringent lockdown measures were implemented during the pandemic.

Methods

We conducted a web-based self-reported survey from November 2020 to December 2020. The study participants (N=2097) were identified through quota sampling by age, sex, and geographical regions among residents aged 19 years or older in Korea. The survey collected information on basic demographics, changes in self-reported health status, and health behaviors during the COVID-19 pandemic. Self-reported health status and health behaviors were categorized into 3 groups: unchanged, improved, or worsened. A chi-square test and logistic regression analyses were conducted.

Results

With regard to changes in the self-reported health status, the majority (1478/2097, 70.5%) of the participants reported that their health was unchanged, while 20% (420/2097) of the participants reported having worser health after the COVID-19 outbreak. With regard to changes in health behaviors, the proportion of participants who increased tobacco consumption was similar to that of those who decreased tobacco consumption (110/545, 20.2% vs 106/545, 19.5%, respectively), while the proportion of those who decreased their drinking frequency was more than twice as many as those who increased their drinking frequency (578/1603, 36.1% vs 270/1603, 16.8%, respectively). Further, those who decreased their exercising frequency were more than those who increased their exercising frequency (333/823, 15.9% vs 211/823, 10%, respectively). The factor that had the greatest influence on lifestyle was age. In the subgroup analysis, the group aged 20-29 years had the highest number of individuals with both a worsened (100/377, 26.5%) and an improved (218/377, 15.7%) health status. Further, individuals aged 20-29 years had greater odds of increased smoking (6.44, 95% CI 2.15-19.32), increased alcohol use (4.64, 95% CI 2.60-8.28), and decreased moderate or higher intensity aerobic exercise (3.39, 95% CI 1.82-6.33) compared to individuals aged 60 years and older. Younger adults showed deteriorated health behaviors, while older adults showed improved health behaviors.

Conclusions

The health status and the behavior of the majority of the Koreans were not found to be heavily affected by the COVID-19 outbreak. However, in some cases, changes in health status or health behavior were identified. This study highlighted that some groups were overwhelmingly affected by COVID-19 compared to others. Certain groups reported experiencing both worsening and improving health, while other groups reported unchanged health status. Age was the most influential factor for behavior change; in particular, the younger generation’s negative health behaviors need more attention in terms of public health. As COVID-19 prolongs, public health interventions for vulnerable groups may be needed.

Impact of doppler velocity index after transcatheter aortic valve replacement using Sapien-3 valve – a single centre experience

Background

Little is known about the hemodynamic performance of Edwards Sapien-3 (S3) valve after Transcatheter Aortic Valve Replacement (TAVR). Doppler velocity index (DVI) is a better indicator of prosthetic valve function as it is independent of valve size and flow, unlike mean gradient and peak velocity which are flow-dependent.

Methods

In this study, we compare outcomes based on differences in DVI among a consecutive series of patients who underwent S3 TAVR between April 2015 and December 2018. Our institutional review board approved the study and informed consents were obtained from the subjects.

Results

Among 921 patients who had follow-up echocardiograms within 30 days after TAVR, 60.8% had DVI ≤0.5, while 39.2% had DVI &gt;0.5. The median 30-day DVI was 0.47 with a standard deviation of 0.11 and mean 0.49 and interquartile range 0.41–0.55. The baseline clinical and procedural characteristics were similar between both groups with the exception of less post-dilation (36.8% vs. 47.4%; p=0.001) and greater implantation depth (2.59±1.99 vs. 2.31±1.9mm; p=0.031) with DVI ≤0.5. The rates of aortic valve calcification, pre dilation, pre-TAVR aortic regurgitation (AR) were similar. At baseline, there were no differences between both groups in mean or peak gradients or aortic velocity time integral (VTI). At 1 year, mean gradients were higher with DVI ≤0.5 (12.7±5.6 vs. 11.1±4.6 mmHg; p=0.001). DVI ≤0.5 was associated with higher peak gradients (24.2±10.2 vs. 21.4±8.7 mmHg; p=0.002), and aortic VTI (51.4±13.5 vs. 46.8±12.2 cm; p&lt;0.001) at 1 year, especially with the 26mm and 29mm prostheses. Compared with DVI&gt;0.5 group, patients in DVI&lt;0.5 group had lower baseline left ventricular ejection fraction (LVEF) (54.5±12.2% vs. 58.9±11.2%; p&lt;0.001), higher left ventricular end-diastolic volume index (LVEDVi) (54.3±20.9 vs. 49.4±17.4 ml/m2; p=0.001), higher LV end-systolic volume index (LVESVi) (25.2±16.5 vs. 21.3±12.7 ml/m2; p=0.001), and similar LV mass index (110.7±31.9 vs. 106.9±32.7 g/m2; p=0.134). 1-year mortality rates among patients who had DVI ≤0.5 compared to DVI &gt;0.5 were lower (6.6% vs. 10.6%; log-rank p=0.033), however no difference was noted at both 2 years (17.3% vs. 20.1%; log-rank p=0.151), and 3 years after TAVR (30.7% vs. 31.2%; log-rank p=0.333).

Conclusions

DVI&lt;0.5 was associated with higher peak gradients and lower baseline LVEF. DVI &lt;0.5 group patients had lower 1-year mortality but similar mortality at 2 and 3-years of follow up.

Funding Acknowledgement

Type of funding sources: None. Figure 1. All-cause SurvivalFigure 2. Hemodynamic Data

Late Clinical and Hemodynamic Outcomes in patients with degenerated bioprosthetic aortic valves undergoing transcatheter valve-in-valve implantation

Background

Clinical studies have shown promising early outcomes for valve-in-valve transcatheter aortic valve implantation (ViV-TAVI); however, the late outcomes of this procedure remain under-investigated.

Purpose

We performed the present analysis to assess the late clinical and hemodynamic outcomes of ViV-TAVI in patients with degenerated bioprosthetic aortic valves.

Methods

A comprehensive chart review was performed for eligible patients to retrieve data on procedural characteristics, admission details following the procedure, and echocardiographic parameters. Clinical outcomes included all-cause mortality, heart failure hospitalization and structural valve deterioration (SVD), as defined by VARC-II criteria, up to 5 years of follow-up. To assess the trends in mean and peak transvalvular gradients, data from the follow-up echocardiographic reports were analyzed using Syngo Dynamics imaging software.

Results

A total of 188 patients were included with a mean age of 75.8±10.4 years. Balloon- and self-expandable valves were used in 155 (82.4%) and 33 (17.6%) patients, respectively. At 30 days, 3 (1.6%) patients died and 8 (4.2%) required hospitalization for heart failure, while at 5 years, both events were recorded in 29 (15.4%) and 37 (19.7) patients, respectively. Kaplan-Meier survival analysis showed that patients with smaller surgical valves (internal diameter ≤21 mm) had a significantly higher mortality rate (log-rank p=0.021) than those with larger valves; however, no significant difference (log-rank p=0.59) was detected between different transcatheter valves (self vs. balloon-expandable). Three patients underwent re-intervention, performed via a transcatheter approach. Further, assessment of follow-up echocardiographic reports revealed 9 (4.8%) cases of SVD, as well as stable mean (16.3±6.9 at discharge and 16.9±11.3) and peak (30.3±12.1 at discharge and 30.7±18.4 at 5 years) transvalvular gradients. No difference (p&gt;0.05) was observed based on transcatheter valve type or surgical valve internal diameter in terms of mean and peak transvalvular gradients throughout the follow-up period.

Conclusion

The present study showed good clinical outcomes among patients undergoing VIV-TAVI, with stable VIV performance over a five-year period. Future long-term studies are warranted to analyze the predictors of outcomes following ViV-TAVI and explore the role of this treatment option in the life-long management of aortic stenosis.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Jennifer and Robert McNeil Donation to the Heart, Thoracic, and Vascular Institute at Cleveland Clinic. Figure 1

Outcomes of transfemoral-transcatheter aortic valve replacement with Sapien-3 valve in liver cirrhosis patients

Background

Little is known about the outcomes of liver cirrhosis patients with severe aortic stenosis (AS) who undergo transcatheter aortic valve replacement (TAVR).

Methods

We undertook a retrospective analysis of consecutive patients with severe symptomatic AS who underwent transfemoral-TAVR with Sapien-3 valve at our Clinic between April 2015 and December 2018, yielding 32 patients with liver cirrhosis on imaging including ultrasound and/or computed tomography. Their baseline characteristics, procedural and long-term outcomes after TAVR with the non-cirrhotic group were compared, along with their management strategies as per the hepatology team.

Results

Among 1028 patients, 32 were assigned to the cirrhosis, and 996 were assigned to the non-cirrhosis (control) group. Compared with the control group cirrhotic patients were slightly younger in age (74.5 vs 81.2 years), had a slightly higher BMI (31.3 vs 29.3), and had a higher incidence of prior history of myocardial infarction (38% vs 33%). Baseline variables including the history of smoking, hypertension, diabetes, and atrial fibrillation were comparable in both groups. Among cirrhotic patients (n=32), the most common etiologies were non-alcoholic steatohepatitis (NASH) (37.5%), Alcoholism (18.75%), and Hepatitis C (12.5%). The mean MELD-NA score was 11.8 and 67% of patients were Child PUGH Class A and 33% were Child PUGH Class B and all patients had a Child PUGH score of ≥5. 53% of patients (n=17) in the cirrhosis group were evaluated by Hepatology and 12.5% (n=4) were evaluated for a liver transplant but only 1 patient had a liver transplant post-TAVR. Compared with the control group cirrhotic patients had similar 1-year mortality (12% vs 12%, p=1), had a lower rate of 30-day new pacemaker post tavr (6% vs 9% p=0.85), had a higher rate of 1-year readmission for heart failure (12% vs 5% p=0.12) and similar 1-year major adverse cardiac and cerebrovascular event (MACCE) rate (15% vs 14% p=0.98)

Conclusion

Patients with severe AS undergoing TAVR with concomitant liver cirrhosis demonstrate comparable outcomes compared with their non- cirrhotic counterparts. NASH followed by alcoholic cirrhosis was found to be most common etiology.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Mortality of Children with Autism Spectrum Disorder Using Data from a Large-Scale Korean National Cohort

PURPOSE

This study aimed to investigate the association between autism spectrum disorder (ASD) diagnosis and mortality among children using the data from a large-scale national cohort of Korean infants and children. We also explored the association between hearing impairment detected during early infancy and mortality.

MATERIALS AND METHODS

We performed a retrospective cohort study using the nationwide claims data of the Republic of Korea. Children born between 2007 and 2014 (n=3598904) were followed up until 2020. Cox proportional hazard models were used to examine the association between ASD diagnosis and mortality among children. Then, in order to evaluate the association between hearing impairment and mortality, Cox proportional hazard models were built using the responses related to hearing impairment asked during the first health screening (at age 4-6 months).

RESULTS

Of the 3598904 children born between 2007 and 2014, 32878 children (0.9%) were diagnosed with ASD until the end of 2020. We identified that ASD diagnosis was associated with higher mortality among children [hazard ratio (HR)=2.5, 95% confidence interval (CI): 2.2-2.9]. This association was stronger among girls (HR=4.8, 95% CI: 3.9-5.8) compared to boys (HR=1.9, 95% CI: 1.6-2.2). We found that hearing impairment detected during infancy was associated with higher mortality among children with ASD diagnosis.

CONCLUSION

ASD diagnosis was associated with higher mortality among Korean children. This association was stronger in girls than in boys. Hearing impairment detected during infancy was also associated with higher mortality among children diagnosed with ASD.

In Situ Formation of Ag Nanoparticles for Fiber Strain Sensors: Toward Textile-Based Wearable Applications

Wearable electronic devices have attracted significant attention as important components in several applications. Among various wearable electronic devices, interest in textile electronic devices is increasing because of their high deformability and portability in daily life. To develop textile electronic devices, fiber-based electronic devices should be fundamentally studied. Here, we report a stretchable and sensitive fiber strain sensor fabricated using only harmless materials during an in situ formation process. Despite using a mild and harmless reducing agent instead of typical strong and hazardous reducing agents, the developed fiber strain sensors feature a low initial electrical resistance of 0.9 Ω/cm, a wide strain sensing range (220%), high sensitivity (∼5.8 × 10⁴), negligible hysteresis, and high stability against repeated stretching-releasing deformation (5000 cycles). By applying the fiber sensors to various textiles, we demonstrate that the smart textile system can monitor various gestures in real-time and help users maintain accurate posture during exercise. These results will provide meaningful insights into the development of next-generation wearable applications.

Comparison of uniaxial and triaxial accelerometer outputs among individuals with and without Down syndrome

BACKGROUND

Using uniaxial accelerometry approach in measuring physical activity levels of individuals with Down syndrome (DS) might underestimate their energy expenditure due to the unique mediolateral walking pattern. Therefore, the purpose of this study was to examine and compare the relationship between two types of accelerometer outputs, uniaxial and triaxial, and energy expenditure in individuals with and without DS.

METHODS

Eighteen participants with DS and 19 participants without DS wore a GT3X+ accelerometer and a portable metabolic system in three different walking conditions.

RESULTS

Correlations between V̇O2 and each of the two accelerometer outputs (uniaxial: r = 0.75, triaxial: r = 0.75) were not significantly different among individuals without DS (z = 0.14, P = 0.89); however, significant differences in the relationship between V̇O2 and accelerometer outputs (uniaxial: r = 0.53, triaxial: r = 0.64) were observed among individuals with DS (z = -1.72, P < 0.046).

CONCLUSIONS

The findings suggest that when using accelerometers to measure physical activity levels for individuals with DS, triaxial outputs may better predict physical activity levels.

Discordance in HER2 status between primary gastric adenocarcinoma tumors and cells from the corresponding malignant effusions

BACKGROUND

Metastasis of gastric cancer commonly manifests as a malignant effusion, which presents an alternative cell source for human epidermal growth factor receptor 2 (HER2) status identification. This study aimed to compare HER2 status in primary gastric adenocarcinoma tumors and corresponding cell blocks prepared from malignant effusions (CB-MEs).

METHODS

HER2 status was retrospectively evaluated by immunohistochemistry (IHC) in primary gastric adenocarcinomas and paired pathologically confirmed CB-MEs of 45 patients. Silver in situ hybridization (SISH) was also performed in cases with IHC 2+ for primary gastric adenocarcinomas and above IHC 1+ for CB-MEs.

RESULTS

HER2 positivity was observed in 4.4% (2/45) of primary gastric adenocarcinomas and 6.7% (3/45) of CB-MEs. The HER2 concordance rate between primary gastric adenocarcinomas and CB-MEs was 88.9% (40/45) (κ = - 0.056). All five patients with HER2 positivity in the primary tumor or a CB-ME had a negative result in the corresponding paired sample. Of the 15 patients with two or more serially sampled CB-MEs, HER2 expression determined by IHC differed between each CB-ME in six (40%) patients, and all three patients with HER2 positivity in CB-MEs exhibited HER2 positivity in one of the serially sampled CB-MEs.

CONCLUSIONS

The HER2 positivity rate was very low in gastric cancer patients with malignant effusions. Our results suggest that HER2 positivity was discordant between the primary gastric adenocarcinoma and corresponding CB-MEs and among serially sampled CB-MEs. The possibility of detecting HER2 positivity can be improved if the primary gastric adenocarcinoma tumor as well as all the available CB-MEs from each patient are analyzed.

Exosomal miR-181b-5p Downregulation in Ascites Serves as a Potential Diagnostic Biomarker for Gastric Cancer-associated Malignant Ascites

Purpose

Peritoneal carcinomatosis in gastric cancer (GC) patients results in extremely poor prognosis. Malignant ascites samples are the most appropriate biological material to use to evaluate biomarkers for peritoneal carcinomatosis. This study identified exosomal MicroRNAs (miRNAs) differently expressed between benign liver cirrhosis-associated ascites (LC-ascites) and malignant gastric cancer-associated ascites (GC-ascites), and validated their role as diagnostic biomarkers for GC-ascites.

Materials and Methods

Total RNA was extracted from exosomes isolated from 165 ascites samples (73 LC-ascites and 92 GC-ascites). Initially, microarrays were used to screen the expression levels of 2,006 miRNAs in the discovery cohort (n=22). Subsequently, quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) analyses were performed to validate the expression levels of selected exosomal miRNAs in the training (n=70) and validation (n=73) cohorts. Furthermore, carcinoembryonic antigen (CEA) levels were determined in ascites samples.

Results

The miR-574-3p, miR-181b-5p, miR-4481, and miR-181d were significantly downregulated in the GC-ascites samples compared to the LC-ascites samples, and miR-181b-5p showed the best diagnostic performance for GC-ascites (area under the curve [AUC]=0.798 and 0.846 for the training and validation cohorts, respectively). The diagnostic performance of CEA for GC-ascites was improved by the combined analysis of miR-181b-5p and CEA (AUC=0.981 and 0.946 for the training and validation cohorts, respectively).

Conclusions

We identified exosomal miRNAs capable of distinguishing between non-malignant and GC-ascites, showing that the combined use of miR-181b-5p and CEA could improve diagnosis.

Efficacy of dimethyl fumarate in Japanese multiple sclerosis patients: interim analysis of randomized, double-blind APEX study and its open-label extension

Background

Current data for the use of dimethyl fumarate (DMF) in Japanese patients with relapsing-remitting multiple sclerosis (RRMS) is limited.

Objectives

To assess the efficacy of DMF in Japanese patients with RRMS.

Methods

The phase 3, multinational APEX study (ClinicalTrials.gov identifier: NCT01838668) consisted of two parts: a 24-week double-blind part where subjects were randomized to receive DMF 240 mg or placebo twice daily in East Asian and Eastern European countries, and an open-label extension part where all subjects received DMF. The primary endpoint was the total number of new gadolinium-enhancing lesions in Weeks 12-24. In this interim analysis, we report efficacy data in the Japanese subgroup (DMF n = 56; placebo n = 58) over 72 weeks, including an extension phase.

Results

DMF reduced the total number of new gadolinium-enhancing lesions in Weeks 12-24 by 85% versus placebo (p < 0.0001). At Week 24, the annualized relapse rate was also reduced by 48% with DMF, versus placebo. DMF reduced the probability of relapse from Week 8 and was sustained. The number of gadolinium-enhancing lesions was maintained through 72 weeks.

Conclusions

DMF demonstrated sustained efficacy in this Japanese subgroup. The results were consistent with those observed in studies of DMF enrolling primarily Caucasian patients.

What Else Is Needed in the Korean Government's Master Plan for People With Developmental Disabilities?

On September 12, 2018, President Jae-In Moon announced the Comprehensive Plan for Lifelong Care for People with Developmental Disabilities, with representatives from the associated government branches (Ministry of Health and Welfare, Ministry of Education, and Ministry of Employment and Labor) in attendance. The goals of this plan are to provide health, medical, rehabilitative, special education, and social welfare services according to the life-stages of the affected individuals; to reduce parental pressure; to promote social interventions; and to enhance community-level participation in order to create a ‘welfare society in harmony.’ However, in order for the plan to succeed, additional efforts must be made in the following areas. First, an epidemiological survey is needed to understand the scale, prevalence, and incidence of developmental disabilities and to establish an evidence base to support policy development. Second, accurate definitions of developmental disabilities must be established in order to avoid policy discrimination based on impairment type and age. Third, personal evaluations to assess disabled individuals’ unmet needs and customized service designs to deliver those needs are required. Fourth, the plan must fulfill the goals of accessibility and fairness that the government intends to provide. Fifth, the government should consider an integrated financial support system and to propose a detailed plan for monetary distributions. Finally, an integrated system that links health, medical, employment, educational, and welfare services must be constructed.

Correction to: Identification of N-arylsulfonylpyrimidones as anticancer agents

The author would like to include conflict of interest statement of the online published article. The correct conflict of interest statement should read as: The authors declare no conflict of interest.

Benproperine, an ARPC2 inhibitor, suppresses cancer cell migration and tumor metastasis

Metastasis is the leading cause of cancer mortality and cancer cell migration is an essential stage of metastasis. We identified benproperine (Benp, a clinically used antitussive drug) as an inhibitor of cancer cell migration and an anti-metastatic agent. Benp selectively inhibited cancer cell migration and invasion, which also suppressed metastasis of cancer cells in animal models. Actin-related protein 2/3 complex subunit 2 (ARPC2) was identified as a molecular target of Benp by affinity column chromatography with Benp-tagged Sepharose beads. Benp bound directly to ARPC2 in cells, which was validated by pull-down assay using Benp-biotin and label-free biochemical methods such as the drug affinity responsive target stability (DARTS) and cellular thermal shift assay (CETSA). Benp inhibited Arp2/3 function, showing disruption of lamellipodial structure and inhibition of actin polymerization. Unlike Arp2/3 inhibitors, Benp selectively inhibited the migration of cancer cells but not normal cells. ARPC2-knockdown cancer cells showed defective cell migration and suppressed metastasis in an animal model. Therefore, ARPC2 is a potential target for anti-metastatic therapy, and Benp has the clinical potential to block metastasis. Furthermore, Benp is a useful agent for studying the functions of the Arp2/3 complex in cancer cell migration and metastasis.

Characterization of morphological changes of B16 melanoma cells under natural killer cell attack

Natural killer (NK) cell killing of melanoma cells involves perforin-mediated delivery of granzymes from NK cells to cancer cells; however, how melanoma cells die remains poorly characterized. Here, we examined the dying process of melanoma cells by using time-lapse imaging. Upon contact with NK cells, B16-F10 cells rounded and most of them showed membrane rupture (98 min); however, B16 parent cells showed writhing and delayed membrane rupture (235 min). This morphological difference depended on the expression levels of myosin regulatory light chain 9 (MYL9) but not activating ligands (CD112, CD155, Rae-1, and MULT-1), SPI, FasL, or PD-L1. Taken together, our data show that melanoma cells show two distinct types of morphological changes upon contact with NK cells and suggest that a strategy to decrease MYL9 expression by melanoma cells may improve the efficacy of NK cell-based immunotherapy.

Tunicamycin-Induced ER Stress is Accompanied with Oxidative Stress via Abrogation of Sulfur Amino Acids Metabolism in the Liver

Endoplasmic reticulum (ER) stress is involved in non-alcoholic fatty liver disease (NAFLD), but the relationship between oxidative stress, another well-known risk factor of NAFLD, and ER stress has yet to be elucidated. In this study, we treated mice with tunicamycin (TM) (2 mg/kg body weight) for 48 h to induce ER stress in the liver and examined the metabolic pathway that synthesizes the endogenous antioxidant, glutathione (GSH). Tunicamycin (TM) treatment significantly increased mRNA levels of CHOP and GRP78, and induced lipid accumulation in the liver. Lipid peroxidation in the liver tissue also increased from TM treatment (CON vs. TM; 3.0 ± 1.8 vs. 11.1 ± 0.8 nmol MDA/g liver, p < 0.001), which reflects an imbalance between the generation of reactive substances and antioxidant capacity. To examine the involvement of GSH synthetic pathway, we determined the metabolomic changes of sulfur amino acids in the liver. TM significantly decreased hepatic S-adenosylmethionine concentration in the methionine cycle. The levels of cysteine in the liver were increased, while taurine concentration was maintained and GSH levels profoundly decreased (CON vs. TM; 8.7 ± 1.5 vs. 5.4 ± 0.9 µmol GSH/g liver, p < 0.001). These results suggest that abnormal cysteine metabolism by TM treatment resulted in a decrease in GSH, followed by an increase in oxidative stress in the liver. In HepG2 cells, decreased GSH levels were examined by TM treatment in a dose dependent manner. Furthermore, pretreatment with TM in HepG2 cells potentiated oxidative cell death, by exacerbating the effects of tert-butyl hydroperoxide. In conclusion, TM-induced ER stress was accompanied by oxidative stress by reducing the GSH synthesis, which made the liver more susceptible to oxidative stress.

A comparison of metabolomic changes in type-1 diabetic C57BL/6N mice originating from different sources

Animal models have been used to elucidate the pathophysiology of varying diseases and to provide insight into potential targets for therapeutic intervention. Although alternatives to animal testing have been proposed to help overcome potential drawbacks related to animal experiments and avoid ethical issues, their use remains vital for the testing of new drug candidates and to identify the most effective strategies for therapeutic intervention. Particularly, the study of metabolic diseases requires the use of animal models to monitor whole-body physiology. In line with this, the National Institute of Food and Drug Safety Evaluation (NIFDS) in Korea has established their own animal strains to help evaluate both efficacy and safety during new drug development. The objective of this study was to characterize the response of C57BL/6NKorl mice from the NIFDS compared with that of other mice originating from the USA and Japan in a chemical-induced diabetic condition. Multiple low-dose treatments with streptozotocin were used to generate a type-1 diabetic animal model which is closely linked to the known clinical pathology of this disease. There were no significantly different responses observed between the varying streptozotocin-induced type-1 diabetic models tested in this study. When comparing control and diabetic mice, increases in liver weight and disturbances in serum amino acids levels of diabetic mice were most remarkable. Although the relationship between type-1 diabetes and BCAA has not been elucidated in this study, the results, which reveal a characteristic increase in diabetic mice of all origins are considered worthy of further study.