Development of a multiplex droplet digital PCR method for detection and monitoring of Mycobacterium tuberculosis and drug-resistant tuberculosis

BACKGROUND

The prevalence of multidrug-resistant tuberculosis (MDR-TB) among Korean tuberculosis patients is about 4.1%, which is higher than the OECD average of 2.6%. Inadequate drug use and poor patient compliance increase MDR-TB prevalence through selective pressure. Therefore, prompt detection of drug resistance in tuberculosis patients at the time of diagnosis and quantitative monitoring of these resistant strains during treatment are crucial.

METHODS

A multiplex droplet digital PCR (ddPCR) assay was developed and assessed using DNA material of nine Mycobacterium tuberculosis strains with known mutation status that were purchased from the Korean National Tuberculosis Association. We collected a total of 18 MDR-TB residual samples referred for PCR analysis. Total DNA was extracted from the samples and subjected to the quadruplex ddPCR assay. Their results were compared to those of known resistance phenotypes.

RESULTS

The analytical sensitivity and specificity of the multiplex ddPCR assay for detecting INH, RIF, EMB, FQ, and SM resistance-causing mutations ranged from 71.43 to 100% and 94.12-100%, respectively. Follow-up sample results showed that the quadruplex ddPCR assay was sensitive enough to detect IS6110 and other mutations even after onset of treatment.

CONCLUSIONS

We developed a sensitive and accurate multiplex ddPCR assay that can detect the presence of tuberculosis quantitatively and resistance-conveying mutations concurrently. This tool could aid clinicians in the diagnosis and treatment monitoring of tuberculosis.

CRISPR-Cas9 and beyond: identifying target genes for developing disease-resistant plants

Throughout the history of crop domestication, desirable traits have been selected in agricultural products. However, such selection often leads to crops and vegetables with weaker vitality and viability than their wild ancestors when exposed to adverse environmental conditions. Considering the increasing human population and climate change challenges, it is crucial to enhance crop quality and quantity. Accordingly, the identification and utilization of diverse genetic resources are imperative for developing disease-resistant plants that can withstand unexpected epidemics of plant diseases. In this review, we provide a brief overview of recent progress in genome-editing technologies, including zinc-finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and clustered regularly interspaced short palindromic repeats (CRISPR)-associated protein 9 (Cas9) technologies. In particular, we classify disease-resistant mutants of Arabidopsis thaliana and several crop plants based on the roles or functions of the mutated genes in plant immunity and suggest potential target genes for molecular breeding of genome-edited disease-resistant plants. Genome-editing technologies are resilient tools for sustainable development and promising solutions for coping with climate change and population increases.

Angiotensin Receptor Blockers and the Risk of Suspected Drug-Induced Liver Injury: A Retrospective Cohort Study Using Electronic Health Record-Based Common Data Model in South Korea

INTRODUCTION

Angiotensin receptor blockers are widely used antihypertensive drugs in South Korea. In 2021, the Korea Ministry of Food and Drug Safety acknowledged the need for national compensation for a drug-induced liver injury (DILI) after azilsartan use. However, little is known regarding the association between angiotensin receptor blockers and DILI.

OBJECTIVE

We conducted a retrospective cohort study in incident users of angiotensin receptor blockers from a common data model database (1 January, 2017-31 December, 2021) to compare the risk of DILI among specific angiotensin receptor blockers against valsartan.

METHODS

Patients were assigned to treatment groups at cohort entry based on prescribed angiotensin receptor blockers. Drug-induced liver injury was operationally defined using the International DILI Expert Working Group criteria. Cox regression analyses were conducted to derive hazard ratios and the inverse probability of treatment weighting method was applied. All analyses were performed using R.

RESULTS

In total, 229,881 angiotensin receptor blocker users from 20 university hospitals were included. Crude DILI incidence ranged from 15.6 to 82.8 per 1000 person-years in treatment groups, most were cholestatic and of mild severity. Overall, the risk of DILI was significantly lower in olmesartan users than in valsartan users (hazard ratio: 0.73 [95% confidence interval 0.55-0.96]). In monotherapy patients, the risk was significantly higher in azilsartan users than in valsartan users (hazard ratio: 6.55 [95% confidence interval 5.28-8.12]).

CONCLUSIONS

We found a significantly higher risk of suspected DILI in patients receiving azilsartan monotherapy compared with valsartan monotherapy. Our findings emphasize the utility of real-world evidence in advancing our understanding of adverse drug reactions in clinical practice.

Electric field simulation and appropriate electrode positioning for optimized transcranial direct current stimulation of stroke patients: an in Silico model

Transcranial Direct Current Stimulation (tDCS) has benefits for motor rehabilitation in stroke patients, but its clinical application is limited due to inter-individual heterogeneous effects. Recently, optimized tDCS that considers individual brain structure has been proposed, but the utility thereof has not been studied in detail. We explored whether optimized tDCS provides unique electrode positions for each patient and creates a higher target electric field than the conventional approach. A comparative within-subject simulation study was conducted using data collected for a randomized controlled study evaluating the effect of optimized tDCS on upper extremity function in stroke patients. Using Neurophet tES LAB 3.0 software, individual brain models were created based on magnetic resonance images and tDCS simulations were performed for each of the conventional and optimized configurations. A comparison of electrode positions between conventional tDCS and optimized tDCS was quantified by calculation of Euclidean distances. A total of 21 stroke patients were studied. Optimized tDCS produced a higher electric field in the hand motor region than conventional tDCS, with an average improvement of 20% and a maximum of 52%. The electrode montage for optimized tDCS was unique to each patient and exhibited various configurations that differed from electrode placement of conventional tDCS. Optimized tDCS afforded a higher electric field in the target of a stroke patient compared to conventional tDCS, which was made possible by appropriately positioning the electrodes. Our findings may encourage further trials on optimized tDCS for motor rehabilitation after stroke.

Improved survival in COVID-19 related sepsis and ARDS treated with a unique "triple therapy" including therapeutic plasma exchange: A single center retrospective analysis

BACKGROUND

Throughout the COVID-19 pandemic, the mortality of critically ill patients remained high. Our group developed a treatment regimen targeting sepsis and ARDS which we labeled "triple therapy" consisting of (1) corticosteroids, (2) therapeutic plasma exchange (TPE), and (3) timely intubation with lung protective ventilation. Our propensity analysis assesses the impact of triple therapy on survival in COVID-19 patients with sepsis and ARDS.

METHODS

Retrospective propensity analysis comparing triple therapy to no triple therapy in adult critically ill COVID-19 patients admitted to the Intensive Care Unit at Lexington Medical Center from 1 March 2020 through 31 October 2021.

RESULTS

Eight hundred and fifty-one patients were admitted with COVID-19 and 53 clinical and laboratory variables were analyzed. Multivariable analysis revealed that triple therapy was associated with increased survival (OR: 1.91; P = .008). Two propensity score-adjusted models demonstrated an increased likelihood of survival in patients receiving triple therapy. Patients with thrombocytopenia were among those most likely to experience increased survival if they received early triple therapy. Decreased survival was observed with endotracheal intubation ≥7 days from hospital admission (P < .001) and there was a trend toward decreased survival if TPE was initiated ≥6 days from hospital admission (P = .091).

CONCLUSION

Our analysis shows that early triple therapy, defined as high-dose methylprednisolone, TPE, and timely invasive mechanical ventilation within the first 96 hours of admission, may improve survival in critically ill septic patients with ARDS secondary to COVID-19 infection. Further studies are needed to define specific phenotypes and characteristics that will identify those patients most likely to benefit.

Benefits of Robot-Assisted Upper-Limb Rehabilitation from the Subacute Stage after a Stroke of Varying Severity: A Multicenter Randomized Controlled Trial

BACKGROUND

The aim of this study was to compare the clinical effectiveness of robot-assisted therapy with that of conventional occupational therapy according to the onset and severity of stroke.

METHODS

In this multicenter randomized controlled trial, stroke patients were randomized (1:1) to receive robot-assisted therapy or conventional occupational therapy. The robot-assisted training group received 30 min of robot-assisted therapy twice and 30 min of conventional occupational therapy daily, while the conventional therapy group received 90 min of occupational therapy. Therapy was conducted 5 days/week for 4 weeks. The primary outcome was the Wolf Motor Function Test (WMFT) score after 4 and 8 weeks of therapy.

RESULTS

Overall, 113 and 115 patients received robot-assisted and conventional therapy, respectively. The WMFT score after robot-assisted therapy was not significantly better than that after conventional therapy, but there were significant improvements in the Motricity Index (trunk) and the Fugl-Meyer Assessment. After robot-assisted therapy, wrist strength significantly improved in the subacute or moderate-severity group of stroke patients.

CONCLUSIONS

Robot-assisted therapy improved the upper-limb functions and activities of daily living (ADL) performance as much as conventional occupational therapy. In particular, it showed signs of more therapeutic effectiveness in the subacute stage or moderate-severity group.

Roles of Inflammatory Biomarkers in Exhaled Breath Condensates in Respiratory Clinical Fields

BACKGROUND

Exhaled condensates contain inflammatory biomarkers; however, their roles in the clinical field have been under-investigated.

METHODS

We prospectively enrolled subjects admitted to pulmonology clinics. We collected exhaled breath condensates (EBC) and analysed the levels of six and 12 biomarkers using conventional and multiplex enzyme-linked immunosorbent assay, respectively.

RESULTS

Among the 123 subjects, healthy controls constituted the largest group (81 participants; 65.9%), followed by the preserved ratio impaired spirometry group (21 patients; 17.1%) and the chronic obstructive pulmonary disease (COPD) group (21 patients; 17.1%). In COPD patients, platelet derived growth factor-AA exhibited strong positive correlations with COPD assessment test (ρ=0.5926, p=0.0423) and COPD-specific version of St. George's Respiratory Questionnaire (SGRQ-C) score (total, ρ=0.6725, p=0.0166; activity, ρ=0.7176, p=0.0086; and impacts, ρ=0.6151, p=0.0333). Granzyme B showed strong positive correlations with SGRQ-C score (symptoms, ρ=0.6078, p=0.0360; and impacts, ρ=0.6007, p=0.0389). Interleukin 6 exhibited a strong positive correlation with SGRQ-C score (activity, ρ=0.4671, p=0.0378). The absolute serum eosinophil and basophil counts showed positive correlations with pro-collagen I alpha 1 (ρ=0.6735, p=0.0164 and ρ=0.6295, p=0.0283, respectively). In healthy subjects, forced expiratory volume in 1 second (FEV1)/forced vital capacity demonstrated significant correlation with CC chemokine ligand 3 (CCL3)/macrophage inflammatory protein 1 alpha (ρ=0.3897 and p=0.0068). FEV1 exhibited significant correlation with CCL11/eotaxin (ρ=0.4445 and p=0.0017).

CONCLUSION

Inflammatory biomarkers in EBC might be useful to predict quality of life concerning respiratory symptoms and serologic markers. Further studies are needed.

Effects of chitinase-1 inhibitor in obesity-induced and -aggravated asthma in a murine model

AIMS

Despite recent investigations on the role of chitinase in asthma, its role in obesity-induced asthma has not been evaluated. Therefore, we investigated the roles of chitin, chitinase-1, and a chitinase-1 inhibitor (compound X, CPX) in a murine model.

MAIN METHODS

We assigned C57BL/6 mice to the ovalbumin (OVA) model or obesity model group. In the OVA model, mice received intraperitoneal OVA twice within a 2-week interval and intranasal OVA for 3 consecutive days. Additionally, chitin was intranasally administered for 3 consecutive days, and CPX was intraperitoneally injected three times over 5 days. In the obesity model, a high-fat diet (HFD) was maintained for 13 weeks, and CPX was intraperitoneally injected eight times over 4 weeks.

KEY FINDINGS

In the OVA model, chitin aggravated OVA-induced airway hyper-responsiveness (AHR), increased bronchoalveolar lavage fluid (BALF) cell proliferation, increased fibrosis, and increased the levels of various inflammatory cytokines (including chitinase-1, TGF-β, TNF-α, IL-1 β, IL-6, IL-4, and IL-13). CPX treatment significantly ameliorated these effects. In the obesity model, HFD significantly increased AHR, BALF cell proliferation, fibrosis, and the levels of various inflammatory cytokines. Particularly, compared to the control group, the mRNA expression of chitinase, chitinase-like molecules, and other molecules associated with inflammation and the immune system was significantly upregulated in the HFD and HFD/OVA groups. Immunofluorescence analysis also showed increased chitinase-1 expression in these groups. CPX significantly ameliorated all these effects in this model.

SIGNIFICANCE

This study showed that CPX can be an effective therapeutic agent in asthma, especially, obesity-induced and -aggravated asthma to protect against the progression to airway remodeling and fibrosis.

Inhibition of Dickkopf-1 enhances the anti-tumor efficacy of sorafenib via inhibition of the PI3K/Akt and Wnt/β-catenin pathways in hepatocellular carcinoma

BACKGROUND

Sorafenib improves the overall survival in patients with advanced hepatocellular carcinoma (HCC). Dickkopf-1 (DKK1) is commonly overexpressed in HCC. In this study, we investigated whether the inhibition of DKK1 enhances the anti-tumor efficacy of sorafenib in HCC.

METHODS

HCC cells were treated with sorafenib and WAY-262611, which is an inhibitor of DKK1. Transgenic mouse models were also developed using hydrodynamic tail vein injection. Mice were orally administered with sorafenib (32 mg/kg), WAY-262611 (16 mg/kg), or sorafenib + WAY-262611 for 10 days. Mechanisms of sorafenib and WAY-262611 were explored via western blotting, immunostaining, and RNA sequencing.

RESULTS

DKK1 was significantly overexpressed in patients with HCC than in the healthy controls and patients with liver diseases except HCC (all P < 0.05). Compared with sorafenib alone, sorafenib + WAY-262611 significantly inhibited the cell viability, invasion, migration, and colony formation by promoting apoptosis and altering the cell cycles in HCC cells (all P < 0.05). Moreover, sorafenib + WAY-262611 decreased the p110α, phospho-Akt (all P < 0.05), active β-catenin (all P < 0.05) and phospho-GSK-3β (Ser9) expression levels, while increasing the phospho-GSK-3β (Tyr216) expression levels compared with those in the sorafenib alone in vitro and in vivo. In addition, sorafenib + WAY-262611 inhibited tumor progression by regulating cell proliferation and apoptosis, significantly better than sorafenib alone in mouse models.

CONCLUSIONS

Our results indicate that DKK1 inhibition significantly enhances the anti-tumor efficacy of sorafenib by inhibiting the PI3K/Akt and Wnt/β-catenin pathways via regulation of GSK3β activity, suggesting a novel therapeutic strategy for HCC. Video Abstract.

Low Skeletal Muscle Mass and Clinical Outcomes in Chronic Obstructive Pulmonary Disease

BACKGROUND

In patients with chronic obstructive pulmonary disease (COPD), decreased muscle mass is a frequently encountered comorbidity in clinical practice. However, the evaluation of muscle mass in patients with COPD in real-world practice is rare.

METHODS

We retrospectively reviewed the electronic medical records of all patients with COPD who underwent bioelectrical impedance analysis at least once between January 2011 and December 2021 in three hospitals. Then, we analyzed the performance rate of muscle mass measurement in the patients and the correlation between muscle mass, clinical parameters, and COPD prognosis.

RESULTS

Among the 24,502 patients with COPD, only 270 (1.1%) underwent muscle mass measurements. The total skeletal muscle mass index was significantly correlated with albumin, alanine transaminase, and creatinine to cystatin C ratio in patients with COPD (r=0.1614, p=0.011; r=0.2112, p=0.001; and r=0.3671, p=0.001, respectively). Acute exacerbation of COPD (AE COPD) was significantly correlated with muscle mass, especially the truncal skeletal muscle mass index (TSMI) in males (r=-0.196, p=0.007). In the multivariate analysis, TSMI and cystatin C were significant risk factors for AE COPD (hazard ratio, 0.200 [95% confidence interval, CI, 0.048 to 0.838] and 4.990 [95% CI, 1.070 to 23.278], respectively).

CONCLUSION

Low muscle mass negatively affects the clinical outcomes in patients with COPD. Despite its clinical significance, muscle mass measurement is performed in a small proportion of patients with COPD. Therefore, protocols and guidelines for the screening of sarcopenia in patients with COPD should be established.

Mortality Risk Factors in Pediatric Onco-Critical Care Patients and Machine Learning Derived Early Onco-Critical Care Phenotypes in a Retrospective Cohort

OBJECTIVES

To use supervised and unsupervised statistical methodology to determine risk factors associated with mortality in critically ill pediatric oncology patients to identify patient phenotypes of interest for future prospective study.

DESIGN

This retrospective cohort study included nonsurgical pediatric critical care admissions from January 2017 to December 2018. We determined the prevalence of multiple organ failure (MOF), ICU mortality, and associated factors. Consensus k-means clustering analysis was performed using 35 bedside admission variables for early, onco-critical care phenotype development.

SETTING

Single critical care unit in a subspeciality pediatric hospital.

INTERVENTION

None.

PATIENTS

There were 364 critical care admissions in 324 patients with underlying malignancy, hematopoietic cell transplant, or immunodeficiency reviewed.

MEASUREMENTS

Prevalence of multiple organ failure, ICU mortality, determination of early onco-critical care phenotypes.

MAIN RESULTS

ICU mortality was 5.2% and was increased in those with MOF (18.4% MOF, 1.7% single organ failure [SOF], 0.6% no organ failure; p ≤ 0.0001). Prevalence of MOF was 23.9%. Significantly increased ICU mortality risk was associated with day 1 MOF (hazards ratio [HR] 2.27; 95% CI, 1.10-6.82; p = 0.03), MOF during ICU admission (HR 4.16; 95% CI, 1.09-15.86; p = 0.037), and with invasive mechanical ventilation requirement (IMV; HR 5.12; 95% CI, 1.31-19.94; p = 0.018). Four phenotypes were derived (PedOnc1-4). PedOnc1 and 2 represented patient groups with low mortality and SOF. PedOnc3 was enriched in patients with sepsis and MOF with mortality associated with liver and renal dysfunction. PedOnc4 had the highest frequency of ICU mortality and MOF characterized by acute respiratory failure requiring invasive mechanical ventilation at admission with neurologic dysfunction and/or severe sepsis. Notably, most of the mortality in PedOnc4 was early (i.e., within 72 hr of ICU admission).

CONCLUSIONS

Mortality was lower than previously reported in critically ill pediatric oncology patients and was associated with MOF and IMV. These findings were further validated and expanded by the four derived nonsynonymous computable phenotypes. Of particular interest for future prospective validation and correlative biological study was the PedOnc4 phenotype, which was composed of patients with hypoxic respiratory failure requiring IMV with sepsis and/or neurologic dysfunction at ICU admission.

Patterns and Longitudinal Changes in The Practice of Breast Cancer Radiotherapy in Korea: Korean Radiation Oncology Group 22-01

PURPOSE/OBJECTIVE(S)

To analyze contemporary practice patterns in breast cancer radiotherapy (RT) and to assess longitudinal changes therein over 5 years in Korea.

MATERIALS/METHODS

A nationwide survey was conducted among board-certified radiation oncologists in Korea by the Division for Breast Cancer of the Korean Radiation Oncology Group in March 2022. The survey consisted of 44 questions related to six domains: hypofractionated (HypoFx) whole breast RT, accelerated partial breast RT (APBI), regional nodal irradiation (RNI), RT for ductal carcinoma in situ (DCIS), postmastectomy RT (PMRT), and tumor bed boost.

RESULTS

In total, 70 radiation oncologists from 61 of 101 (60%) institutions participated in the survey. HypoFx RT was used by 62 respondents (89%), which has significantly increased from 36% in 2017. The HypoFx RT was commonly administered at 40-42.5 Gy in 15-16 fractions. APBI was used by 12 respondents (17%), which has increased from 5% in 2017. The use of RNI did not change significantly: ≥ pN2 (6%), ≥ pN1 (33%), and ≥ pN1 with pathological risk factors (61%). However, the indications for use of internal mammary lymph node (IMN) irradiation have expanded. In particular, the rates of routine treatment of IMN (11% from 6% in 2017) and treatment in cases of ≥ pN2 (27% from 14% in 2017) have doubled; however, the rate of treatment for only IMN involvement, identified on imaging, has decreased to 31% from 47% in 2017. With regard to DCIS, the use of hypoFx RT increased to 75% from 25%, and the rate of omission on of RT after breast-conserving surgery decreased to 38% from 48% in 2017. The use of hypoFx RT for PMRT also increased to 36% from 8% in 2017.

CONCLUSION

The adoption of HypoFx RT after breast-conserving surgery in invasive breast cancer and DCIS has increased significantly, whereas that for PMRT has increased moderately, compared to 2017. Further studies are required to determine the optimal use of RNI.

Hyperferritinemic sepsis, macrophage activation syndrome, and mortality in a pediatric research network: a causal inference analysis

BACKGROUND

One of five global deaths are attributable to sepsis. Hyperferritinemic sepsis (> 500 ng/mL) is associated with increased mortality in single-center studies. Our pediatric research network's objective was to obtain rationale for designing anti-inflammatory clinical trials targeting hyperferritinemic sepsis.

METHODS

We assessed differences in 32 cytokines, immune depression (low whole blood ex vivo TNF response to endotoxin) and thrombotic microangiopathy (low ADAMTS13 activity) biomarkers, seven viral DNAemias, and macrophage activation syndrome (MAS) defined by combined hepatobiliary dysfunction and disseminated intravascular coagulation, and mortality in 117 children with hyperferritinemic sepsis (ferritin level > 500 ng/mL) compared to 280 children with sepsis without hyperferritinemia. Causal inference analysis of these 41 variables, MAS, and mortality was performed.

RESULTS

Mortality was increased in children with hyperferritinemic sepsis (27/117, 23% vs 16/280, 5.7%; Odds Ratio = 4.85, 95% CI [2.55-9.60]; z = 4.728; P-value < 0.0001). Hyperferritinemic sepsis had higher C-reactive protein, sCD163, IL-22, IL-18, IL-18 binding protein, MIG/CXCL9, IL-1β, IL-6, IL-8, IL-10, IL-17a, IFN-γ, IP10/CXCL10, MCP-1/CCL2, MIP-1α, MIP-1β, TNF, MCP-3, IL-2RA (sCD25), IL-16, M-CSF, and SCF levels; lower ADAMTS13 activity, sFasL, whole blood ex vivo TNF response to endotoxin, and TRAIL levels; more Adenovirus, BK virus, and multiple virus DNAemias; and more MAS (P-value < 0.05). Among these variables, only MCP-1/CCL2 (the monocyte chemoattractant protein), MAS, and ferritin levels were directly causally associated with mortality. MCP-1/CCL2 and hyperferritinemia showed direct causal association with depressed ex vivo whole blood TNF response to endotoxin. MCP-1/CCL2 was a mediator of MAS. MCP-1/CCL2 and MAS were mediators of hyperferritinemia.

CONCLUSIONS

These findings establish hyperferritinemic sepsis as a high-risk condition characterized by increased cytokinemia, viral DNAemia, thrombotic microangiopathy, immune depression, macrophage activation syndrome, and death. The causal analysis provides rationale for designing anti-inflammatory trials that reduce macrophage activation to improve survival and enhance infection clearance in pediatric hyperferritinemic sepsis.

Airflow obstruction and chronic obstructive pulmonary disease are common in pulmonary tuberculosis even without sequelae findings on chest X-ray

PURPOSE

Pulmonary tuberculosis (TB) is a well-known risk factor for airflow obstruction and chronic obstructive pulmonary disease (COPD). The prognosis of TB without sequelae on chest X-ray (CXR) remains uncertain.

METHODS

We used the 2008-2009 Korea National Health and Nutrition Examination Survey (KNHANES) data and 2007-2012 KNHANES-matched Health Insurance Review and Assessment Service cohort data. Airflow obstruction was assessed using a pulmonary function test. COPD was defined using diagnostic codes and the use of COPD medication for 3-year. We classified subjects into three groups based on TB history and sequelae on CXR.

RESULTS

In 4911 subjects, the CXR(-) (no TB sequelae on CXR) post-TB group (n = 134) showed similar characteristics and normal lung function compared to that of the control group (n = 4,405), while the CXR(+) (TB sequelae on CXR) post-TB group (n = 372) showed different characteristics and reduced lung function. The prevalence of airflow obstruction was 9.3%, 13.4%, and 26.6% in control, CXR(-) post-TB, and CXR(+) post-TB groups, respectively. COPD was more common in the post-TB with CXR(+) (6.5%) or without CXR (-) (4.5%) groups, than in the control group (1.8%). Compared to the CXR(-) post-TB group, the control group showed a lower risk for airflow obstruction (OR, 0.774; p = .008). The CXR(+) post-TB group showed a higher risk for airflow obstruction (OR, 1.456; p = .011). The Control group also showed a lower risk for the development of COPD than the CXR(-) post-TB group (OR, 0.496; p = .011).

CONCLUSIONS

We need to educate TB patients that airway obstruction and COPD can easily develop, even if TB sequelae are not observed on CXR.

Long-Term Clinical Outcomes of Patients with Chronic Obstructive Pulmonary Disease with Sarcopenia

BACKGROUND AND OBJECTIVE

Sarcopenia with muscle wasting and weakness is a common occurrence among patients with chronic obstructive pulmonary disease (COPD). We aimed to evaluate the clinical outcomes of sarcopenia in patients with COPD.

METHODS

We reviewed the electronic medical records of 71 patients with COPD between 1 January 2012, and 31 December 2018. We longitudinally analyzed clinical outcomes in patients with COPD with and without sarcopenia.

RESULTS

Compared to the non-sarcopenia group COPD, the sarcopenia group showed a higher rate of acute exacerbation events of COPD (AE COPD, 84.6% vs. 31.0%, p = 0.001), all-cause mortality (30.8% vs. 5.2%, p = 0.022), and pneumonia occurrence per year (median [first quartile-third quartile]; 0.2 [0.0-1.6] vs. 0.0 [0.0-0.2], p = 0.025). Sarcopenia was an independent risk factor for AE COPD in Cox regression analysis (hazard ratio, 5.982; 95% confidence interval, 1.576-22.704). Hand grip strength was associated with the COPD Assessment Test (CAT) score and annual Charlson's comorbidity index score change. Total skeletal muscle mass index (SMMI) was associated with the modified medical research council dyspnea scale score, CAT score, body mass index, airflow obstruction, dyspnea, and exercise (BODE) index, and alanine transaminase. Trunk SMMI was significantly associated with AE COPD, while appendicular SMMI was associated with BODE index and annual intensive care unit admissions for AE COPD.

CONCLUSIONS

Sarcopenia is associated with clinical prognosis, pneumonia occurrence, and the acute exacerbation of COPD requiring intensive care in patients with COPD. Therefore, it is important to carefully monitor sarcopenia development as well as recommend appropriate exercise and nutritional supplementation in patients with COPD.

Asthma and increased risk of myocardial infarction and mortality among hypertensive Korean patients

This study aimed to evaluate the effects of asthma on cardiovascular disease incidence in patients with hypertension. A total of 639,784 patients with hypertension from the Korea National Health Insurance Service database were included, of whom 62,517 had history of asthma after propensity score matching. The risks of all-cause mortality, myocardial infarction (MI), stroke, and end-stage renal disease (ESRD) were assessed according to the presence of asthma, long-acting β2-agonist (LABA) inhaler usage, and/or systemic corticosteroid usage for up to 11 years. In addition, whether these risks were modified by average blood pressure (BP) levels during the follow-up period was examined. Asthma was associated with an increased risk of all-cause mortality (hazard ratio [HR], 1.203; 95% confidence interval [CI], 1.165-1.241) and MI (HR, 1.244; 95% CI, 1.182-1.310) but not the risk of stroke or ESRD. LABA inhaler usage was associated with a higher risk of all-cause mortality and MI, and systemic corticosteroids usage showed a higher risk of ESRD as well as all-cause mortality and MI among hypertensive patients with asthma. Compared to patients without asthma, there was a graded increase in the risk of all-cause mortality and MI in those with asthma without LABA inhaler/systemic corticosteroid usage and in those with asthma with LABA inhaler/systemic corticosteroid usage. These associations were not significantly modified by BP levels. This nationwide population-based study supports that asthma may be a clinical factor that increases the risk of poor outcomes in patients with hypertension.

Safety and therapeutic effects of personalized transcranial direct current stimulation based on electrical field simulation for prolonged disorders of consciousness: study protocol for a multi-center, double-blind, randomized controlled trial

Background

Disorders of consciousness (DOC) resulting from acquired brain injury (ABI) increase the mortality rate of patients, complicate rehabilitation, and increase the physical and economic burden that DOC imposes on patients and their families. Thus, treatment to promote early awakening from DOC is vital. Transcranial direct current stimulation (tDCS) has shown great potential for promoting neuro-electrochemical activity. However, previous tDCS studies did not consider structural damage or head and brain lesions, so the applicability of the results to all DOC patients was limited. In this study, to establish a patient-specific tDCS treatment plan considering the brain lesions of and damage sustained by DOC patients, we considered the electric field calculated by a the "finite electric" three-dimensional brain model based on magnetic resonance images. This protocol was developed to aid tDCS treatment of actual patients, and to verify its safety and effectiveness.

Methods/design

Twenty-four patients with DOC after ABI will be enrolled in this cross-over trial. All participants will receive typical rehabilitation combined with sham tDCS and typical rehabilitation plus personalized tDCS (P-tDCS). Each interventional period will last 2 weeks (30 min/day, 5 days/week). The primary outcome [score on the Korean version of the Coma Recovery Scale-Revised (K-CRS-R)] will be assessed at baseline and the end of the first day of the intervention. Secondary outcomes (K-CRS-R at 1 week and 2 weeks after experimental session and quantitative EEG changes quantitative electroencephalography changes) will be measured at baseline and the end of week 4. Adverse events will be recorded during each treatment session.

Discussion

For patients with neurological disorders, tDCS has served as a painless, non-invasive, easily applied, and effective therapy for several decades, and there is some evidence that it can improve the level of consciousness of patients with DOC. However, variability in the effects on consciousness among subjects have been reported and personalized strategies are lacking. This protocol is for a randomized controlled trial designed to validate the effectiveness and safety of P-tDCS combined with typical rehabilitation for DOC.

Clinical trial registration

https://cris.nih.go.kr, identifier KCT0007157.

Outstanding Characteristics of Birt-Hogg-Dube Syndrome in Korea

Birt-Hogg-Dube (BHD) is a rare genetic disorder characterized by multiple lung cysts, typical skin manifestations, and renal tumors. We prospectively enrolled thirty-one subjects from four South Korean institutions with typical lung cysts, and next-generation sequencing was conducted. We prospectively enrolled thirty-one subjects from four Korean institutions with typical lung cysts. Next-generation sequencing was performed to investigate mutations in the following genes: FLCN, TSC1, TSC2, CFTR, EFEMP2, ELN, FBLN5, LTBP4, and SERPINA1. BHD was diagnosed in 11 of the 31 enrolled subjects (35.5%; FLCN mutations). Notably, we identified three novel mutations (c.1098G>A, c.139G>T, and c.1335del) that have not been previously reported. In addition to FLCN mutations, we also observed mutations in CFTR (16.1%), LTBP4 (9.7%), TSC2 (9.7%), TSC1 (3.2%), ELN (3.2%), and SERPINA1 (3.2%). According to a systematic review of 45 South Korean patients with BHD, the prevalence of pneumothorax (72.7%) was greater in South Korea than in the rest of the world (50.9%; p = 0.003). The prevalence of skin manifestations (13.6%) and renal tumors (9.1%) was lower in Korea than in the rest of the world, at 47.9% [p < 0.001] and 22.5% [p = 0.027], respectively). This study confirmed a significant prediction model for BHD based on age, number of lung cysts (>40), and maximal diameter of lung cysts (>2 cm) regardless of skin manifestations and renal tumors. Importantly, three novel mutations (c.1098G>A, c.139G>T, and c.1335del) were identified. In conclusion, South Korean patients with BHD display characteristics that are different from those observed in patients of other nationalities. Detailed characterization of lung cysts is needed to define BHD, especially in South Korea, even if patients do not present with skin or renal lesions.

Association between Serum Levels of Interleukin-25/Thymic Stromal Lymphopoietin and the Risk of Exacerbation of Chronic Obstructive Pulmonary Disease

Th2 inflammation is associated with various characteristics of patients with chronic obstructive pulmonary disease (COPD). In this study, we analyzed the COPD exacerbation risk associated with serum levels of interleukin (IL)-25/thymic stromal lymphopoietin (TSLP) and eosinophils. We studied the KOCOSS cohort, a multicenter COPD cohort created by 54 medical centers in South Korea. We extracted data collected between April 2012 and August 2020. We measured serum levels of TSLP and IL-25 in those who agreed to provide blood, and assessed exacerbation risk according to each. In all, 562 patients were enrolled. The IL-25-high group had a lower St. George's Respiratory Questionnaire score than others, and the TSLP-high group had a poorer exercise capacity than the TSLP-low group. There were no significant differences in the forced expiratory volume in 1 s (FEV1), the levels of Th2 inflammatory biomarkers, or the exacerbation histories between the two groups. The 3-year decline in FEV1 was not significantly affected by IL-25 or TSLP levels. In terms of 1-year exacerbation risk, individuals in the IL-25-high group were at lower risk for moderate-to-severe exacerbation than others. A high TSLP level was associated with a lower risk of severe exacerbation but only in the eosinophil-low group. Serum levels of IL-25 are negatively correlated with moderate-to-severe exacerbation risk in this cohort. A negative correlation between severe exacerbation risk and TSLP level was apparent only in the eosinophil-low group.

Particulate matter10-induced airway inflammation and fibrosis can be regulated by chitinase-1 suppression

BACKGROUND

Particulate matter₁₀ (PM₁₀) can induce airway inflammation and fibrosis. Recently, chitinase-1 has been shown to play key roles in inflammation and fibrosis. We aimed to investigate the effects of chitinase-1 inhibitor in PM₁₀-treated murine mice models.

METHODS

In female BALB/c mice, PM₁₀ was intranasally administered six times over 3 weeks, and ovalbumin (OVA) was intraperitoneally injected and then intranasally administered. Chitinase-1 inhibitor (CPX) 6 times over 3 weeks or dexamethasone 3 times in the last week were intraperitoneally administered. Two days after the last challenges, mice were euthanized. Messenger RNA sequencing using lung homogenates was conducted to evaluate signaling pathways.

RESULTS

PM₁₀ and/or OVA-induced airway inflammation and fibrosis murine models were established. CPX and dexamethasone ameliorated PM₁₀ or PM₁₀/OVA-induced airway hyper-responsiveness, airway inflammation, and fibrosis. CPX and dexamethasone also reduced levels of various inflammatory markers in lung homogenates. PM₁₀ and OVA also induced changes in mRNA expression across an extreme range of genes. CPX and dexamethasone decreased levels of mRNA expression especially associated with inflammation and immune regulation. They also significantly regulated asthma and asthma-related pathways, including the JACK-STAT signaling pathway.

CONCLUSIONS

Chitinase-1 suppression by CPX can regulate PM₁₀- and OVA-induced and aggravated airway inflammation and fibrosis via an asthma-related signaling pathway.

Analysis of Hepatitis C Virus Resistance-Associated Substitutions in Direct-Acting Antiviral Failure in South Korea Using Next-Generation Sequencing

Background/Aims

We analyzed resistance-associated substitutions (RAS) and retreatment outcomes in patients with chronic hepatitis C virus (HCV) infection who failed direct-acting antiviral agent (DAA) treatment in South Korea using next-generation sequencing (NGS).

Methods

Using prospectively collected data from the Korea HCV cohort study, 36 patients who failed DAA treatment were recruited from 10 centers between 2007 and 2020; 29 blood samples were available from 24 patients. RASs were analyzed using NGS.

Results

RAS was analyzed for 13 patients with genotype 1b, ten with genotype 2, and one with genotype 3a. The unsuccessful DAA regimens were daclatasvir+asunaprevir (n=11), sofosbuvir+ribavirin (n=9), ledipasvir/sofosbuvir (n=3), and glecaprevir/pibrentasvir (n=1). In patients with genotype 1b, NS3, NS5A, and NS5B RASs were detected in eight, seven, and seven out of ten patients at baseline and in four, six, and two out of six patients after DAA failure, respectively. Among ten patients with genotype 2, the only baseline RAS was NS3 Y56F, detected in one patient. NS5A F28C was detected after DAA failure in a patient with genotype 2 infection erroneously treated with daclatasvir+asunaprevir. After retreatment 16 patients had a 100% sustained virological response rate.

Conclusions

NS3 and NS5A RASs were commonly present at baseline, and there was an increasing trend of NS5A RAS after failed DAA treatment in genotype 1b. However, RAS was rarely present in patients with genotype 2 treated with sofosbuvir plus ribavirin. Despite baseline or treatment-emergent RAS, retreatment with pan-genotypic DAA was highly successful in Korea, encouraging active retreatment for unsuccessful DAA treatment.

Effect of supplementation of cryoprotectant solution with hydroxypropyl cellulose for vitrification of bovine oocytes

BACKGROUND

Successful cryopreservation of bovine oocytes is very important for research and commercial applications. However, the survival and development rate of vitrified-thawed (VT) oocytes are lower than those of non-vitrified-thawed (non-VT) oocytes.

OBJECTIVE

To investigate the effect of adding hydroxypropyl cellulose (HPC) to the vitrification solution for bovine oocytes.

MATERIALS AND METHODS

For vitrification, bovine metaphase II oocytes were pretreated with a solution containing 10% ethylene glycol supplemented with 0, 10, 50, or 100 ug/mL HPC for 5 min, exposed to a solution containing 30% ethylene glycol supplemented with 0, 10, 50, or 100 ug/mL HPC for 30 s, and then directly plunged into liquid nitrogen.

RESULTS

The survival rate of oocytes was significantly higher in the 50 HPC group than in the 0, 10, and 100 HPC groups. The reactive oxygen species level was lower in the non-VT and 50 HPC groups than in the other groups. The mRNA levels of proapoptotic genes (Bax) were lower in the non-VT, 0, and 50 HPC groups than in the other groups. The mRNA levels of antiapoptotic genes (BCl2) were higher in the non-VT than in the other groups. The development rates of embryos (day 8) obtained via parthenogenetic activation (PA) were determined in the non-VT, 0 HPC, and 50 HPC groups. The cleavage rate was significantly higher in the non-VT group.

CONCLUSION

Supplementation of vitrification solution with HPC improves the survival of VT bovine oocytes and the development capacity of embryos derived from these oocytes via PA. doi.org/10.54680/fr23110110212.

Multicenter Prospective Observational Study to Evaluate the Therapeutic Effect and Safety of a Combination of Montelukast and Levocetirizine for Allergic Rhinitis when Administered to Patients with Allergic Rhinitis and Asthma

INTRODUCTION

Allergic rhinitis and asthma share a common inflammatory mechanism and are closely related, recognized as "one airway disease." Thus, the guidelines recommend allergic rhinitis and asthma be treated together, and leukotriene antagonists and antihistamines have been administered simultaneously; however, there are few reports of the use of combination drugs so far.

METHODS

The aim of the study was to evaluate the treatment effects and adverse events of Monterizine® (a combination of montelukast and levocetirizine); a total of 2,254 patients with perennial allergic rhinitis and asthma were prospectively enrolled from 60 hospitals nationwide in Korea. They were followed up for 3 (Period 1) or 6 months (Period 2). Total nasal symptom score (TNSS), satisfaction, and safety data were collected and compared to baseline.

RESULTS

TNSS scores were analyzed for 2,254 subjects. At Period 1 (n = 2,024) and 2 (n = 1,861), the scores decreased significantly from baseline (-1.20 ± 2.49 and -1.63 ± 2.78, p < 0.001). The mean quality of life (QoL) was significantly improved at Period 1 and 2 relative to baseline (-3.75 ± 6.58, -4.83 ± 7.11, both p < 0.0001). There were no serious adverse drug reactions, but there were some minor reactions including nasopharyngitis (2.92%), rhinitis (0.37%), and somnolence (0.34%).

CONCLUSIONS

TNSS score and QoL were significantly improved by 3-6 months' treatment with Monterizine without significant adverse reactions. These results indicate that Monterizine, as a combination drug, is effective and safe for improving nasal symptoms and quality of life in patients with allergic rhinitis who also have asthma.

Applications of molecular barcode sequencing for the detection of low-frequency variants in circulating tumour DNA from hepatocellular carcinoma

PURPOSE

Liquid biopsy has emerged as a promising tool for minimally invasive and accurate detection of various malignancies. We aimed to apply molecular barcode sequencing to circulating tumour DNA (ctDNA) from liquid biopsies of hepatocellular carcinoma (HCC).

STUDY DESIGN

Patients with HCC or benign liver disease were enrolled between 2017 and 2018. Matched tissue and serum samples were obtained from these patients. Plasma cell-free DNA was extracted and subjected to targeted sequencing with ultra-high coverage and molecular barcoding.

RESULTS

The study included 143 patients: 102 with HCC, 7 with benign liver tumours and 34 with chronic liver disease. No tier 1/2 or oncogenic mutations were detected in patients with benign liver disease. Among the HCC patients, 49 (48%) had tier 1/2 mutations in at least one gene; detection rates were higher in advanced stages (75%) than in early stages (26%-33%). TERT was the most frequently mutated gene (30%), followed by TP53 (16%), CTNNB1 (14%), ARID2 (5%), ARID1A (4%), NFE2L2 (4%), AXIN1 (3%) and KRAS (1%). Survival among patients with TP53 mutations was significantly worse (p = 0.007) than among patients without these mutations, whereas CTNNB1 and TERT mutations did not affect survival. ctDNA testing combined with α-fetoprotein and prothrombin induced by vitamin K absence-II analyses improved HCC detection, even in early stages.

CONCLUSIONS

ctDNA detection using molecular barcoding technology offers dynamic and personalized information concerning tumour biology, such information can guide clinical diagnosis and management. This detection also has the potential as a minimally invasive approach for prognostic stratification and post-therapeutic monitoring.

A Comparison of the Effectiveness of Asthma Medications on Asthma Exacerbations in Real World National Cohort

Background

Although a wide variety of asthma medications have been developed and are used in clinical practice, there is limited evidence of their comparative effects on asthma exacerbations.

Methods

We used claims data provided by the Health Insurance Review and Assessment Service. We selected subjects commencing asthma treatment between July 1, 2017 and June 30, 2018, with no change in drug regimen. The primary outcome was asthma exacerbation requiring systemic corticosteroids. Cox regression analysis was used to assess outcomes considering the exacerbation-free period.

Results

Of the 254,951 asthma subjects, 107,694 subjects (42.2%) experienced asthma exacerbation. Inhaled corticosteroids (ICSs) (hazard ratio [HR], 0.378–0.508), ICS-long-acting β₂-agonist (LABAs) (HR, 0.284–0.479), long-acting muscarine antagonists (LAMAs) (HR, 0.432–0.572), leukotriene receptor antagonists (LTRAs) (HR, 0.371–0.419), and xanthines (HR, 0.326–0.482) significantly reduced the rate of first and second exacerbation of asthma (all P-values, <0.001). The clinical effectiveness of asthma medications varied according to the active ingredient (HR 0.164–0.670) and was significant for all active ingredients (all P-values, <0.001). The effectiveness of combination treatment using ICS-LABA and LTRA varied (HR, 0.159–0.670); however, all combination treatment options evaluated were effective in preventing asthma exacerbations (all P-values, <0.001). Long-term use of ICS-LABA (HR, 0.278–0.653), LTRA (HR, 0.259–0.628), and xanthines (HR, 0.351–0.783) showed consistent effectiveness (all P-values, <0.001).

Conclusion

This real-world study showed that the effectiveness of asthma medications varied according to drug type, active ingredient, combination, and period of use, although effectiveness was significant in all cases studied.

Co-administration of ursodeoxycholic acid with rosuvastatin/ezetimibe in a non-alcoholic fatty liver disease model

Background

Ursodeoxycholic acid (UDCA), statins, and ezetimibe (EZE) have demonstrated beneficial effects against non-alcoholic fatty liver disease (NAFLD). We investigated the efficacy of the combination of UDCA and the mix of rosuvastatin (RSV)/EZE in the treatment of NAFLD.

Methods

NAFLD mouse models were developed by injecting thioacetamide, fasting, and high-carbohydrate refeeding, high-fat diet, and choline-deficient L-amino acid-defined high-fat diet (CDAHFD). Low-dose UDCA (L-UDCA; 15 mg/kg) or high-dose UDCA (H-UDCA; 30 mg/kg) was administered with RSV/EZE. We also employed an in vitro model of NAFLD developed using palmitic acid-treated Hepa1c1c7 cells.

Results

Co-administration of RSV/EZE with UDCA significantly decreased the collagen accumulation, serum alanine aminotransferase (ALT) levels, and mRNA levels of fibrosis-related markers than those observed in the vehicle group in thioacetamide-treated mice (all P < 0.01). In addition, in the group fasted and refed with a high-carbohydrate diet, UDCA/RSV/EZE treatment decreased the number of apoptotic cells and serum ALT levels compared with those observed in the vehicle group (all P < 0.05). Subsequently, H-UDCA/RSV/EZE treatment decreased the number of ballooned hepatocytes and stearoyl-CoA desaturase 1 (SCD-1) mRNA levels (P = 0.027) in the liver of high-fat diet-fed mice compared with those observed in the vehicle group. In the CDAHFD-fed mouse model, UDCA/RSV/EZE significantly attenuated collagen accumulation and fibrosis-related markers compared to those observed in the vehicle group (all P < 0.05). In addition, UDCA/RSV/EZE treatment significantly restored cell survival and decreased the protein levels of apoptosis-related markers compared to RSV/EZE treatment in palmitic acid-treated Hepa1c1c7 cells (all P < 0.05).

Conclusion

Combination therapy involving UDCA and RSV/EZE may be a novel strategy for potent inhibition of NAFLD progression.

Differences in the Recurrence Rate of Immediate Adverse Drug Reactions According to the Components of Alternative Contrast Media: Analysis of Repetitive Computed Tomography Cases in a Single Tertiary Hospital

INTRODUCTION

The recurrence rates of immediate adverse drug reactions (ADRs) to the alternative radiocontrast media (RCM) are not well known. Previous studies suggest selection of alternative RCM considering carbamoyl side chains; however, its usefulness for preventing the recurrence of ADRs has not been clearly verified.

OBJECTIVE

The aim of this study was to verify the recurrence rate of immediate ADRs according to the alternative RCM.

METHOD

This retrospective study analyzed 6420 contrast-enhanced computed tomography (CT) cases of 2009 patients registered in the ADR system from 861,664 CT cases in a single tertiary hospital between 2015 and 2020. Iohexol, iopromide, iobitridol, and iopamidol were used for CT. According to the carbamoyl side chains present, iohexol belongs to group 1, iopromide belongs to groups 1 and 2, iobitridol belongs to group 2, and iopamidol belongs to group 3.

RESULTS

Replacing iobitridol with iopamidol (odds ratio [OR] 2.595, 95% confidence interval [CI] 1.48-4.550) or iopromide (OR 3.354, 95% CI 1.420-7.926) as the subsequent RCM was associated with increased recurrence, while replacing iopamidol with iobitridol (OR 0.506, 95% CI 0.282-0.908) and iopromide with iohexol (OR 0.355, 95% CI 0.177-0.711) was associated with decreased recurrence. Other changes did not influence the recurrence of ADRs.

CONCLUSIONS

The recurrence of immediate ADRs increased in certain RCM combinations of preceding and subsequent CT scans, and the RCMs did not show cross-reactivity. Therefore, the clinical benefit of the alternative RCM considering cross-reactivity is limited. This result suggests that the side chains of RCM do not have an important role in the recurrence of immediate ADRs.

Effects of Asthma Medication Type on Asthma Exacerbation in a Real-World Setting

PURPOSE

Currently, there are multiple options for the pharmacological treatment of asthma. This study aimed to compare the effects of different asthma medications on exacerbation in a real-world setting.

MATERIALS AND METHODS

We retrospectively reviewed electronic medical records of asthma patients who visited the hospital from November 1, 2016 to October 31, 2019. The number of asthma exacerbations requiring administration of systemic steroids was the primary outcome. A time-varying Cox regression analysis was used to reflect the real-world setting: variable usage times, discontinuation, and switching of medication.

RESULTS

Among 937 patients with asthma, 228 (24.3%) experienced asthma exacerbation during the study period. Asthma exacerbation was observed in patients using short-acting β₂-agonists (SABA) alone (50.4% vs. 28.6%, p<0.001) as well as in patients not using inhaled corticosteroids (ICS) (58.8% vs. 40.3%, p<0.001), long-acting β₂-agonists (LABA) (54.8% vs. 36.1%, p<0.001), and leukotriene receptor antagonists (71.5% vs. 50.8%, p<0.001). A time-varying Cox regression analysis of asthma exacerbations according to the duration of asthma medication showed that SABA alone increased the risk of asthma exacerbation [hazard ratio (HR), 1.834; 95% confidence interval (CI), 1.299-2.588; p=0.001], whereas ICS-LABA decreased the risk (HR, 0.733; 95% CI, 0.538-0.997; p=0.048). However, in the subgroup analysis according to medication type, specific ingredients showed no significant differences.

CONCLUSION

In the real world, asthma medications affect asthma exacerbation variably according to the medication type.

Effect of supplementation of cryoprotectant solution with hydroxypropyl cellulose for vitrification of bovine oocytes

BACKGROUND

Successful cryopreservation of bovine oocytes is very important for research and commercial applications. However, the survival and development rate of vitrified-thawed (VT) oocytes are lower than those of non-vitrified-thawed (non-VT) oocytes.

OBJECTIVE

To investigate the effect of adding hydroxypropyl cellulose (HPC) to the vitrification solution for bovine oocytes.

MATERIALS AND METHODS

For vitrification, bovine metaphase II oocytes were pretreated with a solution containing 10% ethylene glycol supplemented with 0, 10, 50, or 100 ug/mL HPC for 5 min, exposed to a solution containing 30% ethylene glycol supplemented with 0, 10, 50, or 100 ug/mL HPC for 30 s, and then directly plunged into liquid nitrogen.

RESULTS

The survival rate of oocytes was significantly higher in the 50 HPC group than in the 0, 10, and 100 HPC groups. The reactive oxygen species level was lower in the non-VT and 50 HPC groups than in the other groups. The mRNA levels of proapoptotic genes (Bax) were lower in the non-VT, 0, and 50 HPC groups than in the other groups. The mRNA levels of antiapoptotic genes (BCl2) were higher in the non-VT than in the other groups. The development rates of embryos (day 8) obtained via parthenogenetic activation (PA) were determined in the non-VT, 0 HPC, and 50 HPC groups. The cleavage rate was significantly higher in the non-VT group.

CONCLUSION

Supplementation of vitrification solution with HPC improves the survival of VT bovine oocytes and the development capacity of embryos derived from these oocytes via PA. doi.org/10.54680/fr23110110212.

E-cigarette-associated Severe Pneumonia in Korea Using Data Linkage between the Korea National Health and Nutrition Examination Survey (KNHANES, 2013-2019) and the National Health Insurance Service (NHIS) Claims Database

BACKGROUND

This study aimed to investigate the association between e-cigarette (EC) use and development of acute severe pneumonia in the Korean population using a national database.

METHODS

We conducted a retrospective analysis using linkage of data between the Korean National Health and Nutrition Examination Survey (KNHANES) and the National Health Insurance Service (NHIS) administrative claims database. The primary endpoint of this study was development of severe pneumonia requiring hospital admission according to EC use during the study period. The secondary endpoints were in-hospital mortality, intensive care unit (ICU) admission, ventilator care, and days of hospital stay.

RESULTS

The final analysis included 28,950 individuals, of which 578 (2.0%) were EC users. EC users were younger and more often male than non-EC users. The EC users showed higher level of education and household income and had fewer comorbidities. Severe pneumonia was noted in 37 of 28,372 non-EC users (0.13%), but there were no occurrences of severe pneumonia in EC users. The incidence of pneumonia occurrence was not different between the two groups (P = 1.000).

CONCLUSIONS

Since e-cigarette or vaping use-associated lung injury (EVALI) is most likely included in acute severe pneumonia occurring within 3 months of EC use, it is considered that there might be no EVALI patients in Korea during the investigation period. A large-scale, prospective study is necessary to evaluate the association between EC use and acute lung injury.

Dickkopf-1 promotes angiogenesis by upregulating VEGF receptor 2-mediated mTOR/p70S6K signaling in hepatocellular carcinoma

The expression of Dickkopf-1 (DKK1), a negative regulator of the Wnt/β-catenin signaling pathway, is upregulated in hepatocellular carcinoma (HCC). Here, we investigated the tumorigenic and angiogenic potential of DKK1 in HCC. Stable cell lines were established using the clustered regularly interspaced short palindromic repeats (CRISPR)-associated nuclease 9 (CRISPR/Cas9)-based DKK1 knock-out system in Hep3B cells and the tetracycline-based DKK1 inducible system in Huh7 cells. Multicellular tumor spheroids (MCTSs) were cultured using Hep3B stable cells. We also employed xenografts generated using Hep3B stable cells and transgenic mouse models established using hydrodynamic tail vein injection. The angiogenic potential increased in HUVECs treated with CM from Huh7 stable cells with high DKK1 expression and Hep3B wild-type cells. DKK1 accelerated the downstream molecules of vascular endothelial growth factor receptor 2 (VEGFR2)-mediated mTOR/p70 S6 kinase (p70S6K) signaling. MCTSs generated using Hep3B wild-type cells promoted compact spheroid formation and increased the expression of CD31 and epithelial-mesenchymal transition (EMT) markers, and increased the VEGFR2-mediated mTOR/p70S6K signaling, compared to the controls (all P<0.01). Xenograft tumors generated using Hep3B cells with DKK1 knock-out (n=10) exhibited slower growth than, the controls (n=10) and the expression of Ki-67, VEGFR2, CD31 and EMT markers decreased (all P<0.05). In addition, forced DKK1 expression with HRAS in transgenic mouse livers (n=5) resulted in the formation of more tumors and increased expression of downstream molecules of VEGFR2-mediated mTOR/p70S6K signaling pathway as well as Ki67, CD31 and EMT markers (P<0.05), compared to that of the controls (n=5). Our findings indicate that DKK1 facilitates angiogenesis and tumorigenesis by upregulating VEGFR2-mediated mTOR/p70S6K signaling in HCC.

Prediction of radiation-related cardiotoxicity using F-18 FDG PET in non-small-cell lung cancer

Background

Radiation-related cardiotoxicity has been refocused nowadays as the follow-up was increased amomg the patients with advanced lung cancer. The early recognition of the occult cardiotoxicity enables the early intervention preventing clinically significant cardiac events or worsening of severity.

Purpose

We aim to search whether the F-18 fluorodeoxyglucose positron emission tomography (FDG PET) performed immediately after radiotherapy could predict the late cardiac events.

Methods

We retrospectively enrolled 133 patients with locally advanced, unresectable stage III NSCLC who underwent F-18 fluorodeoxyglucose positron emission tomography (FDG PET) immediately after CCRT for the response evaluation and survived at least for 6 months. Heart was recontoured according to the RTOG 0617 secondary analysis atlas for the dose volume analysis. Standardized uptake values (SUV) of the left ventricular myocardium were measured on FDG PET images. The patients were regularly followed up for the disease progression and complications. The primary end-point was the cardiac events grade ≥2 based on the Common Terminology Criteria for Adverse Events (version 5.0).

Results

FDG PET was performed at median interval of 11 days after CCRT. Fourty-two patients experienced cardiotoxicity during a median follow-up of 47 months (range, 12 – 123 months). In univariable analysis, mean heart dose, maximum SUV of the left ventricle (LV SUVmax), white blood cell count, and diabetes were associated with the risk of cardiotoxicity. In multivariable analysis, only higher mean heart dose (&gt;11.1 Gy, hazard ratio 3.930 [95% confidence interval 1.933–7.988]; p=0.0002) and higher LV SUVmax (&gt;12.84, 2.189 [1.162–4.124]; p=0.0152) were independently associated with increased risk of cardiotoxicity. In subgroup analyses, LV SUVmax remained predictive of cardiotoxicity among those with higher mean heart dose, but not among those with lower mean heart dose.

Conclusion

Early FDG PET after CCRT for NSCLC could predict the late cardiac events, especially in patients with high dose cardiac irradiation.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): This work was supported by a grant of the Basic Science Research Program through the National Research Foundation funded by the Ministry of Education, Republic of Korea (Principal Investigator: Sang-Geon Cho)

Trends in ESBLs and PABLs among enteric Salmonella isolates from children in Gwangju, Korea: 2014-2018

OBJECTIVES

Non-typhoid Salmonella infection is a major agent of food-borne outbreaks as well as individual cases worldwide. However, few studies on drug-resistant Salmonella strains, especially those recovered from young children, are available. Therefore, we determined the prevalence and characteristics of cephalosporin-resistant Salmonella isolates in the south-west region of Korea over a five-year period.

METHODS

Non-duplicate Salmonella clinical isolates were recovered from diarrhoeagenic patient specimens at 12 hospitals in Gwangju, Korea between January 2014 and December 2018. Antimicrobial susceptibility testing and molecular features of cephalosporin-resistant isolates were determined.

RESULTS

A total of 652 Salmonella isolates were collected and 48 cefotaxime-resistant Salmonella isolates (7.4%), that belonged to nine Salmonella serovars, were identified. These were S. Enteritidis, S. Typhimurium, S. I 4,[5],12:i:-, S. Virchow, S. Agona, S. Bareilly, S. Infantis, S. Newport, and S. Schleissheim. The prevalence rate increased from 5.3% in 2014 to 10.3% in 2018. S. Virchow (44.4%) showed significantly high resistant rate compared to the other serovars. PGFE genotyping revealed high genetic homogeneities among each Salmonella serovars, suggesting clonal dissemination of cephalosporin-resistant strains.

CONCLUSIONS

Progressive increases in carriage rates and the possibility of community outbreaks by cephalosporin-resistant Salmonella in young children may pose tangible public health threats.

A pilot investigation of e-cigarette use and smoking behaviour among patients with chronic airway disease or respiratory symptoms

Background

This pilot study aimed to investigate the current status of e‐cigarettes (ECs) use patterns among patients with chronic airway disease or chronic respiratory symptoms and the effects of ECs use on respiratory and mental health.

Methods

A cross‐sectional survey was conducted at the outpatient clinic of eight teaching hospitals in South Korea between November 2019 and December 2019. All adult ECs users (19 years and above) who visited the outpatient clinic as a patient with chronic airway disease or chronic respiratory symptoms were eligible to participate in this study.

Results

A total of 51 subjects responded to the survey. Most of the participants were male (92.2%) and the mean age was 41.8 years. Dominant airway diseases were asthma and chronic obstructive pulmonary disease. Most of the subjects had a history of cigarette smoking, and 19 subjects were dual users of current cigarettes and ECs. Most of the subjects started ECs use due to health‐related reasons. When comparing exclusive ECs users and dual users, St. George's respiratory questionnaire (SGRQ) scores, the proportion of cases with moderate to severe depressive symptoms, and average Fagerstrom test for nicotine dependence scores for ECs were higher in dual users than exclusive ECs users (mean 4.64 vs. 2.38, p = 0.006), respectively.

Conclusion

Most of the subjects started ECs use due to health concerns, but dual users have more respiratory symptoms and higher nicotine dependence in this pilot study. One hypothesis that comes from these results is that greater nicotine dependence may influence behaviours, habits, and views about ECs. These preliminary observations need confirmation in a large cohort.

Low alanine aminotransferase as a risk factor for chronic obstructive pulmonary disease in males

Alanine aminotransferase (ALT) levels reflect skeletal muscle volume and general performance, which are associated with chronic obstructive pulmonary disease (COPD) development and prognosis. This study aimed to investigate ALT levels as a risk factor for COPD development. This 13-year population-based retrospective observational cohort study included 422,452 participants for analysis. We classified groups according to the baseline ALT levels (groups 1-5: ALT (IU/L) < 10; 10-19; 20-29; 30-39; and ≥ 40, respectively). The incidence of COPD was the highest in group 1, decreasing as the group number increased in males, but not in females. The Cox regression analysis in males revealed that a lower ALT level, as a continuous variable, was a significant risk factor for COPD development [univariable, hazard ratio (HR): 0.992, 95% confidence interval (CI): 0.991-0.994; multivariable, HR: 0.998, 95% CI: 0.996-0.999]. In addition, COPD was more likely to develop in the lower ALT level groups (groups 1-4; < 40 IU/L), than in the highest ALT level group (group 5; ≥ 40 IU/L) (univariable, HR: 1.341, 95% CI: 1.263-1.424; multivariable, HR: 1.097, 95% CI: 1.030-1.168). Our findings suggest that males with low ALT levels should be carefully monitored for COPD development.

Variable effects of underlying diseases on the prognosis of patients with COVID-19

Underlying diseases might be risk factors for poor prognosis in patients with coronavirus disease (COVID-19); however, we still do not know whether these diseases are independent factors affecting prognosis, which type of underlying diseases are risk factors, and which type of clinical outcomes are affected. We retrospectively reviewed cohort data from 7,590 de-identified patients with COVID-19 who were diagnosed using severe acute respiratory syndrome-coronavirus-2 RNA polymerase chain reaction test up to May 15, 2020. We used linked-medical claims data provided by the Health Insurance Review and Assessment Service in South Korea. Underlying diseases were identified using the diagnostic codes in the patients’ files from January 1, 2019 to December 31, 2019. The total mortality rate was 3.0% in patients with COVID-19. After adjusting for age, sex, and concomitant chronic conditions, we found that congestive heart failure, chronic pulmonary diseases, diabetes without chronic complications, renal diseases, and malignancy were factors that significantly increased the cost of treatment. Cerebrovascular disease, chronic pulmonary disease, and paralysis were found to be independent factors significant in prolonging hospital stay. Diabetes with chronic complications was independently associated with intensive care unit admission. In addition, underlying congestive heart failure (odds ratio [OR], 1.724; P = 0.003), dementia (OR, 1.598; P = 0.012), diabetes with and without chronic complications (OR, 1.821; P = 0.002 and OR, 1.518; P = 0.022, respectively), renal disease (OR, 2.299; P = 0.002), and malignancy (OR, 1.529; P = 0.039) were significant factors associated with death, even after adjustments. Underlying diseases were significant independent factors of the poor prognosis in patients with COVID-19. The effects were variable according to the type of underlying disease and clinical outcome. Therefore, patients with COVID-19 with underlying diseases should be monitored more closely because they are more at risk of a poor prognosis.

Intralymphatic immunotherapy with tyrosine-adsorbed allergens: a double-blind, placebo-controlled trial

Background

Most previous studies used aluminum hydroxide-absorbed allergen extracts in evaluating the potential therapeutic roles of intralymphatic allergen-specific immunotherapy (ILAIT). In this study, we evaluated the therapeutic efficacy and safety of ILAIT with L-tyrosine-adsorbed allergen extracts of Dermatophagoides farinae, D. pteronyssinus, cat, dog, or mixtures thereof, in patients with allergic rhinitis induced by these allergens.

Methods

In this randomized, double-blind, placebo-controlled trial, study subjects received three intralymphatic injections of L-tyrosine-adsorbed allergen extracts (active group) or saline (placebo group) at 4-week intervals.

Results

Although ILAIT reduced daily medication use and skin reactivity to HDM and cat allergens at 4 months after treatment, overall symptom score on a visual analog scale (VAS), sinonasal outcome test-20 (SNOT-20), rhinoconjunctivitis quality of life questionnaire (RQLQ), daily symptom score (dSS), daily medication score (dMS), daily symptom medication score (dSMS), nasal reactivity to HDM allergen, and basophil activity to HDM, cat, and dog allergens at 4 months and 1 year after treatment were similar between the treatment and control groups. Intralymphatic injection was more painful than a venous puncture, and pain at the injection site was the most frequent local adverse event (12.8%); dyspnea and wheezing were the most common systemic adverse events (5.3%).

Conclusions

ILAIT with L-tyrosine-adsorbed allergen extracts does not exhibit profound therapeutic efficacy in allergic rhinitis and can provoke moderate-to-severe systemic reactions and cause pain at the injection site.

Trial registration: clinicaltrials.gov: NCT02665754; date of registration: 28 January 2016

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-021-01766-0.

Reliability of Portable Spirometry Performed in the Korea National Health and Nutrition Examination Survey Compared to Conventional Spirometry

Background

The Korea National Health and Nutrition Examination Survey (KNHANES) is a well-designed survey to collect national data, which many researchers have used for their studies. In KNHANES, although portable spirometry was used, its reliability has not been verified.

Methods

We prospectively enrolled 58 participants from four Korean institutions. The participants were classified into normal pattern, obstructive pattern, and restrictive pattern groups according to their previous spirometry results. Lung function was estimated by conventional spirometry and portable spirometry, and the results were compared.

Results

The intraclass correlation coefficients of forced vital capacity (FVC) (coefficient, 9.993; 95% confidence interval [CI], 0.988–0.996), forced expiratory volume in 1 second (FEV₁) (coefficient, 0.997; 95% CI, 0.995–0.998), FEV₁/FVC ratio (coefficient, 0.995; 95% CI, 0.992–0.997), and forced expiratory flow at 25–75% (FEF25–75%; coefficient, 0.991; 95% CI, 0.984–0.994) were excellent (all p<0.001). In the subgroup analysis, the results of the three parameters were similar in all groups. In the overall and subgroup analyses, Pearson’s correlation of all the parameters was also excellent in the total (coefficient, 0.986–0.994; p<0.001) and subgroup analyses (coefficient, 0.915–0.995; p<0.001). In the paired t-test, FVC, FEV₁/FVC, and FEF25–75% estimated by the two instruments were statistically different. However, FEV₁ was not significantly different.

Conclusion

Lung function estimated by portable spirometry was well-correlated with that estimated by conventional spirometry. Although the values had minimal differences between them, we suggest that the spirometry results from the KNHANES are reliable.

Influence of government-driven quality assessment program on patients with chronic obstructive pulmonary disease

Background

The Korean Health Insurance Review and Assessment Service (HIRA) has launched the Chronic Obstructive Pulmonary Disease (COPD) Quality Assessment Program (CQAP) since 2014. We aimed to reveal the influence of this national program on clinical outcomes and the burden of COPD in Korea.

Methods

The CQAP is conducted annually. We used healthcare claims data linked with the results of the program provided by HIRA between May 2014 and April 2017. Patients were considered to have COPD if they visited a hospital for COPD management during the assessment term. Those who visited a medical institution for COPD and were prescribed COPD medications at least twice were assessed by the CQAP (assessed subjects, AS; not-assessed subjects, NAS). CQAP evaluated the pulmonary function test conduction rate, regular visitation rate, and prescription rates of COPD medications.

Results

Among the 560,000 patients with COPD, about 140,000 were assessed by the CQAP annually. In both groups, the pulmonary function test conduction rate and inhaled bronchodilator prescription rate improved since 2014. Compared to the NAS group, the risk of admission and all-cause mortality rate in the AS group were significantly reduced by 21.2% and 40.7%, respectively. In patients who were assessed for 3 consecutive years, all of the above variables were high at baseline and were not improved much from implementation of CQAP. In matching analysis, we observed this improvement to be limited in the COPD quality assessment year.

Conclusions

The CQAP by the health insurance bureau has improved the management protocol and prognosis of COPD.

Obesity-induced Vitamin D Deficiency Contributes to Lung Fibrosis and Airway Hyperresponsiveness

Vitamin D (VitD) has pleiotropic effects. VitD deficiency is closely involved with obesity and may contribute to the development of lung fibrosis and aggravation of airway hyperresponsiveness (AHR). We evaluated the causal relationship between VitD deficiency and the lung pathologies associated with obesity. In vivo effects of VitD supplementation were analyzed using high-fat diet (HFD)-induced obese mice and TGF-β1 (transforming growth factor-β1) triple transgenic mice. Effects of VitD supplementation were also evaluated in both BEAS-2B and primary lung cells from the transgenic mice. Obese mice had decreased 25-OH VitD and VitD receptor expressions with increases of insulin resistance, renin and angiotensin-2 system (RAS) activity, and leptin. In addition, lung pathologies such as a modest increase in macrophages, enhanced TGF-β1, IL-1β, and IL-6 expression, lung fibrosis, and AHR were found. VitD supplementation to HFD-induced obese mice recovered these findings. TGF-β1-overexpressing transgenic mice enhanced macrophages in BAL fluid, lung expression of RAS, epithelial-mesenchymal transition markers, AHR, and lung fibrosis. VitD supplementation also attenuated these findings in addition to the attenuation of the expressions of TGF-β1, and phosphorylated Smad-2/3 in lung. Supplementing in vitro-stimulated BEAS-2B and primary lung cells with VitD inhibited TGF-β1 expression, supporting the suppressive effect of VitD for TGF-β1 expression. These results suggest that obesity leads to VitD deficiency and worsens insulin resistance while enhancing the expression of leptin, RAS, TGF-β1, and proinflammatory cytokines. These changes may contribute to the development of lung fibrosis and AHR. VitD supplementation rescues these changes and may have therapeutic potential for asthma with obesity.

Effect of asthma and asthma medication on the prognosis of patients with COVID-19

BACKGROUND

Coronavirus disease 2019 (COVID-19) has spread worldwide rapidly. However, the effects of asthma, asthma medication and asthma severity on the clinical outcomes of COVID-19 have not yet been established.

METHODS

The study included 7590 de-identified patients, who were confirmed to have COVID-19 using the severe acute respiratory syndrome coronavirus 2 RNA-PCR tests conducted up to May 15, 2020; we used the linked-medical claims data provided by the Health Insurance Review and Assessment Service. Asthma and asthma severity (steps suggested by the Global Initiative for Asthma) were defined using the diagnostic code and history of asthma medication usage.

RESULTS

Among 7590 COVID-19 patients, 218 (2.9%) had underlying asthma. The total medical cost associated with COVID-19 patients with underlying asthma was significantly higher than that of other patients. Mortality rate for COVID-19 patients with underlying asthma (7.8%) was significantly higher than that of other patients (2.8%; p<0.001). However, asthma was not an independent risk factor for the clinical outcomes of COVID-19 after adjustment, nor did asthma medication use and asthma severity affect the clinical outcomes of COVID-19. However, use of oral short-acting β2-agonists was an independent factor to increase the total medical cost burden. Patients with step 5 asthma showed significant prolonged duration of admission compared to those with step 1 asthma in both univariate and multivariate analysis.

CONCLUSIONS

Asthma led to poor outcomes of COVID-19; however, underlying asthma, use of asthma medication and asthma severity were not independent factors for poor clinical outcomes of COVID-19, generally.

Nicotine Dependence and Stress Susceptibility in E-Cigarette Smokers: The Korea National Health and Nutrition Examination Survey 2013-2017

Background

E-cigarettes are steadily gaining popularity in Korea. However, the characteristics of e-cigarette smokers, especially nicotine dependence and stress susceptibility, have not been evaluated in comparison to those of nonsmokers or combustible cigarette smokers in Korea.

Methods

In this study, 28,059 participants from the Korea National Health and Nutrition Examination Survey (2013–2017) were classified into the following three groups: non-smokers, smokers (current smokers and ex-smokers of combustible cigarettes only), and e-smokers (current smokers and ex-smokers of e-cigarettes regardless of combustible cigarette use).

Results

Among the participants, 16,980 (60.5%), 9,247 (33.0%), and 1,832 (6.4%) subjects were non-smokers, smokers, and e-smokers, respectively. E-smokers were younger, more educated, and had a higher household income than nonsmokers or smokers. The number of e-smokers who smoked within 5 minutes of waking up (31.5% vs. 19.8%, p<0.001) and who planned to quit smoking within 6 months (39.1% vs. 35.7%, p<0.05) was greater than that of smokers. E-smokers perceived stress as “very much” (7.0% vs. 4.4%, p<0.001) and “a lot” (29.1% vs. 20.5%, p<0.001) compared to non-smokers. Suicidal ideation (6.5% vs. 4.7%, p<0.001), plans (2.4% vs. 1.3%, p<0.001), and attempts (1.1% vs. 0.5%, p<0.001) were higher in e-smokers than in non-smokers. Depressive episodes in 1 year (14.2% vs. 11.4%, p<0.05) and suicidal plans (2.4% vs. 1.8%, p<0.05) were more frequent among e-smokers than among smokers.

Conclusion

E-smokers were younger, more educated, and had a higher income, but they were more dependent on nicotine and susceptible to stress than non-smokers and smokers. Smoking cessation counseling should be tailored according to the characteristics of e-smokers.