Synthesis and evaluation of antibody-drug conjugates with high drug-to-antibody ratio using dimaleimide-DM1 as a linker- payload.

The notable characteristics of recently emerged Antibody-Drug Conjugates (ADCs) encompass the targeting of Human Epidermal growth factor Receptor 2 (HER2) through monoclonal antibodies (mAbs) and a high ratio of drug to antibody (DAR). The achievements of Kadcyla® (T-DM1) and Enhertu® (T-Dxd) have demonstrated that HER2-targeting antibodies, such as trastuzumab, have shown to be competitive in terms of efficacy and price for development. Furthermore, with the arrival of T-Dxd and Trodelvy®, high-DAR (7-8) ADCs, which differ from the moderate DAR (3-4) ADCs that were formerly regarded as conventional, are being acknowledged for their worth. Following this trend of drug development, we endeavored to develop a high-DAR ADC using a straightforward approach involving the utilization of DM1, a highly potent substance, in combination with the widely recognized trastuzumab. To achieve a high DAR, DM1 was conjugated to reduced cysteine through the simple design and synthesis of various dimaleimide linkers with differing lengths. Using LC and MS analysis, we have demonstrated that our synthesis methodology is uncomplicated and efficacious, yielding trastuzumab-based ADCs that exhibit a remarkable degree of uniformity. These ADCs have been experimentally substantiated to exert an inhibitory effect on cancer cells in vitro, thus affirming their value as noteworthy additions to the realm of ADCs.

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.

Exploring structural and biological insights of TEAD through rational design and synthesis of niflumic acid derivatives.

Transcriptional enhanced associate domain (TEAD) transcription factors undergo auto-palmitoylation, which is critical to mediate their function and maintain stability. Targeting the palmitate binding pocket of TEAD holds considerable promise for drug discovery, and it can be characterised into three components: a conserved cysteine, a hydrophobic main pocket, and a hydrophilic side pocket. Endogenous palmitate and several known TEAD inhibitors interact with the cysteine and hydrophobic residues in the deep hydrophobic pocket. We anticipate that precise targeting of the polar side pocket could facilitate the discovery of inhibitors with enhanced potencies and properties. Herein, we selected niflumic acid as the core scaffold suitable for targeting the three characteristic components of TEAD palmitate pocket. Reversible and irreversible compounds with substituents capable of directing each part of the palmitate pocket were designed. The newly synthesised compounds inhibited the palmitoylation and transcriptional activity of TEAD and elicited growth-inhibitory effects against several carcinomas, including mesothelioma.

Antimicrobial Use and Carbapenem-Resistant Enterobacterales in Korea: A Nationwide Case-Control Study With Propensity Score Matching.

BACKGROUND: Nationwide research on the association between carbapenem-resistant Enterobacterales (CREs) and antibiotic use is limited. METHODS: This nested case-control study analyzed Korean National Health Insurance claims data from April 2017 to April 2019. Based on the occurrence of CRE, hospitalized patients aged ≥ 18 years were classified into CRE (cases) and control groups. Propensity scores based on age, sex, modified Charlson comorbidity score, insurance type, long-term care facility, intensive care unit stay, and acquisition of vancomycin-resistant Enterococci were used to match the case and control groups (1:3). RESULTS: After matching, the study included 6,476 participants (1,619 cases and 4,857 controls). Multivariable logistic regression analysis revealed that the utilization of broad-spectrum antibiotics, such as piperacillin/tazobactam (adjusted odds ratio [aOR], 2.178; 95% confidence interval [CI], 1.829-2.594), third/fourth generation cephalosporins (aOR, 1.764; 95% CI, 1.514-2.056), and carbapenems (aOR, 1.775; 95% CI, 1.454-2.165), as well as the presence of comorbidities (diabetes [aOR, 1.237; 95% CI, 1.061-1.443], hemiplegia or paraplegia [aOR, 1.370; 95% CI, 1.119-1.679], kidney disease [aOR, 1.312; 95% CI, 1.105-1.559], and liver disease [aOR, 1.431; 95% CI, 1.073-1.908]), were significantly associated with the development of CRE. Additionally, the CRE group had higher mortality (8.33 vs. 3.32 incidence rate per 100 person-months, P < 0.001) and a total cost of healthcare utilization per person-month (15,325,491 ± 23,587,378 vs. 5,263,373 ± 14,070,118 KRW, P < 0.001) than the control group. CONCLUSION: The utilization of broad-spectrum antibiotics and the presence of comorbidities are associated with increasing development of CRE. This study emphasizes the importance of antimicrobial stewardship in reducing broad-spectrum antibiotic use and CRE disease burden in Korea.

Prevalence and Associated Factors of Depression and Anxiety Among Healthcare Workers During the Coronavirus Disease 2019 Pandemic: A Nationwide Study in Korea.

BACKGROUND: A healthcare system's collapse due to a pandemic, such as the coronavirus disease 2019 (COVID-19), can expose healthcare workers (HCWs) to various mental health problems. This study aimed to investigate the impact of the COVID-19 pandemic on the depression and anxiety of HCWs. METHODS: A nationwide questionnaire-based survey was conducted on HCWs who worked in healthcare facilities and public health centers in Korea in December 2020. Patient Health Questionnaire-9 (PHQ-9) and Generalized Anxiety Disorder-7 (GAD-7) were used to measure depression and anxiety. To investigate factors associated with depression and anxiety, stepwise multiple logistic regression analysis was performed. RESULTS: A total of 1,425 participating HCWs were included. The mean depression score (PHQ-9) of HCWs before and after COVID-19 increased from 2.37 to 5.39, and the mean anxiety score (GAD-7) increased from 1.41 to 3.41. The proportion of HCWs with moderate to severe depression (PHQ-9 ≥ 10) increased from 3.8% before COVID-19 to 19.5% after COVID-19, whereas that of HCWs with moderate to severe anxiety (GAD-7 ≥ 10) increased from 2.0% to 10.1%. In our study, insomnia, chronic fatigue symptoms and physical symptoms after COVID-19, anxiety score (GAD-7) after COVID-19, living alone, and exhaustion were positively correlated with depression. Furthermore, post-traumatic stress symptoms, stress score (Global Assessment of Recent Stress), depression score (PHQ-9) after COVID-19, and exhaustion were positively correlated with anxiety. CONCLUSION: In Korea, during the COVID-19 pandemic, HCWs commonly suffered from mental health problems, including depression and anxiety. Regularly checking the physical and mental health problems of HCWs during the COVID-19 pandemic is crucial, and social support and strategy are needed to reduce the heavy workload and psychological distress of HCWs.

Associations Among Family Strengths, Depression and Life Satisfaction Between Disabled Children and Their Parent Caregivers: An Actor-Partner Interdependence Mediation Model.

AIM: To explore the actor-partner effect and mediating role of depression on family strength and life satisfaction among children with disabilities and their parent-caregiver dyads. DESIGN: A cross-sectional study using secondary data collected from the 2020 (third) Korea Disability and Life Dynamics Panel. METHODS: This study included 434 Korean dyads of children with disabilities and their parent caregivers. A dyadic analysis was performed using the actor-partner interdependence mediation model. RESULTS: The findings showed significant indirect actor effects of family strength on life satisfaction through depression for children with disabilities and their parent caregivers. The direct partner effects of one's family strengths on a partner's life satisfaction were statistically significant only for children. Additionally, significant indirect partner effects were observed in the association between parents' family strengths and children's life satisfaction through their own and their children's depression. The findings indicated that the life satisfaction of children with disabilities was more likely to be affected by their parent caregivers' perceived family strengths and depression. CONCLUSION: It is significant for health professionals to acknowledge the mediating and cross-over pathways linking family strengths to life satisfaction through depression and, thus, focus on family-based strategies to enhance life satisfaction among children with disabilities and their parent caregivers. IMPLICATIONS FOR THE PROFESSION AND/OR PATIENT CARE: This study highlights the need for family-oriented mental health interventions and education to promote life satisfaction among children with disabilities and their parent caregivers. IMPACT: Basic data were provided for establishing efficient healthcare education and counselling protocols and integrated family intervention programmes that can contribute to improving life satisfaction through the reduction of depression by strengthening the family strengths of disabled children-parent caregivers dyads. In future, studies should explore dyadic interdependence among children with disabilities and their parent caregivers. REPORTING METHOD: STROBE guidelines were followed for this study. PATIENT OR PUBLIC CONTRIBUTION: No public or patient contribution was required for this study.

The Effects of Workplace Spirituality and Self-Efficacy on Quality of Life Among Cancer Survivors: Empirical Quantitative Research.

AIMS: To investigate the impact of workplace spirituality and self-efficacy (SE) on cancer survivors' quality of life (QOL) and develop nursing interventions. DESIGN: Descriptive survey. METHODS: Participants were cancer survivors treated at Chung-Ang hospital in Seoul. They were administered a questionnaire covering general and clinical characteristics, workplace spirituality, SE and QOL. Data were analysed using hierarchical multiple regression analyses. RESULTS: Workplace spirituality, SE and QOL were positively correlated. Higher education level, work in the health/medical sector, higher monthly income, undetermined cancer stage or not currently undergoing cancer treatment and absence of physical impairments or comorbidities due to cancer influenced QOL. Regression analysis revealed that SE enhanced QOL. CONCLUSION: Workplace spirituality and SE correlated with QOL. Notably, SE actively enhanced QOL by providing inner strength regardless of the type of treatment or its physical damage. IMPLICATIONS FOR THE PROFESSION: The findings have practical implications for the development of nursing interventions that aim to boost the confidence and positive assurance of employed cancer survivors in managing their condition and to enhance QOL. IMPACT: Problem addressed: Understanding the impact of workplace spirituality and SE on cancer survivors' QOL. MAIN FINDINGS: Positive correlations between workplace spirituality, SE and QOL; SE as a primary determinant of QOL. Impact location and population: Relevant to cancer patients managing treatment and work responsibilities, contributing to improved QOL. REPORTING METHOD: Adhered to relevant EQUATOR guidelines. PATIENT OR PUBLIC CONTRIBUTION: No contribution. TRIAL AND PROTOCOL REGISTRATION: Not applicable.

Spousal support, parent-nurse partnership and caregiver burden among parents of children with chronic diseases: A cross-sectional study.

AIM: To examine the effects of spousal support and parent-nurse partnership on caregiver burden of parents of children with chronic disease. BACKGROUND: With the trend of increasing the global number of children with chronic diseases, the parental caregiver burden has become increasingly prevalent. DESIGN: Cross-sectional study. METHODS: The study participants included 115 parents of children diagnosed with chronic disease at a general hospital in South Korea. The study duration was 4 June 2021-30 April 2022. Self-reported measures included the parent-nurse partnership scale, the Korean version of the Parenting Alliance Inventory and the family caregiver burden scale. T-tests, ANOVA, Pearson's correlation coefficients and hierarchical linear multiple regression were conducted using IBM SPSS version 26.0. This study followed STROBE guideline. RESULTS: Parental caregiver burden was significantly negatively associated with spousal support and parent-nurse partnership. Factors significantly influencing caregiver burden were parental alcohol consumption; child's inherited metabolic disease, cardiovascular disease, disease relating to haematological tumours or kidney disease diagnosis; child's health perceived as poor by parents; child's dependency perceived as high by parents; hospitalization recency; and low spousal support. These factors accounted for 65% of caregiver burden. CONCLUSION: Parental caregiver burden was related to spousal support and parent-nurse partnership, but the primary factor affecting caregiver burden was spousal support. RELEVANCE TO CLINICAL PRACTICE: The results highlighted the role of healthcare professionals in educating parents of children with chronic diseases to facilitate spousal support and have implications for nursing and community-based interventions to reduce parental caregiver burden. Furthermore, they underlined that policymakers and other stakeholders should pay attention to the parental caregiver burden through government-based, family-centered strategies. PATIENT OR PUBLIC CONTRIBUTION: Parents of children with chronic disease were recruited to perform the self-administered survey in the phase of data collection.

Factors Associated With Health-Promoting Behaviors Among South Korean Adults: A Cross-Sectional Study.

OBJECTIVE: To examine the association between positive psychological capital, social support, illness attitudes toward COVID-19, and health-promoting behaviors in Korean adults. DESIGN: An online cross-sectional study. SAMPLE: The participants were 820 South Korean adults aged 19-64, recruited through quota sampling. The sample was census-matched in terms of age and gender based on the Korean Population Census. MEASUREMENTS: The participants completed measures assessing psychological capital, social support, illness attitude toward COVID-19, and health-promoting behaviors. The t-test, one-way analysis of variance, Pearson's correlation, and multiple stepwise regression analysis were used to analyze the data. RESULTS: Participants who were religious, perceived themselves as physically healthy, had negative illness attitudes, had high positive psychological capital, and received high social support were more likely to engage in health-promoting behaviors. These variables explained 44.5% of the participants' health-promoting behaviors. CONCLUSIONS: This study is the first to examine illness attitudes toward COVID-19 and health-promoting behaviors among South Korean adults during the COVID-19 pandemic. The results can pave the way for effective public health intervention strategies that consider religiosity, physical health status, illness attitude, and social support, to promote healthy living during future public health crises.

Nursing students' clinical practice education experience during the COVID-19 pandemic: a qualitative study.

BACKGROUND: Nursing education, including some elements of clinical practice, has largely been conducted online during the coronavirus disease 2019 (COVID-19) pandemic. Numerous studies have examined the experiences of nursing students in academia during the pandemic. However, research on nursing students' clinical practice experiences is limited. This study aimed to analyze nursing students' clinical practice experiences during the COVID-19 pandemic. METHODS: This study used a qualitative research design and performed thematic analysis. Participants comprised 13 nursing university students with clinical practice experience at a hospital during the COVID-19 pandemic. Interviews were conducted either online or face-to-face. Data were collected during June‒July 2021. RESULTS: Four themes and eight subthemes were generated through thematic analysis. Theme 1 was "Nursing students' anxiety and strict adherence to quarantine practices," with the subthemes of "Fear of infection" and "Protecting themselves." Theme 2 was "Nursing students' belief that their organization is protecting them," with the subthemes of "Strict quarantine rules at hospitals and universities" and "The nursing students regretted the limited scope of practice but felt safe." Theme 3 was "Learning through valuable practice," with the subthemes of "Recognizing the importance of practice" and "Realizing the benefits of practice." Theme 4 was "A sense of duty as a prospective nurse," with the subthemes of "Accepting a sense of duty as a nurse" and "Establishing the expanded role of a nurse." CONCLUSIONS: The nursing students recognized the importance of nursing practice during the pandemic and worked harder. A better understanding of the experiences of nursing university students who completed their clinical practice during the COVID-19 pandemic can help nursing professors and managers more effectively train students during times of high stress.

Translation and psychometric evaluation of the Korean version of the Reproductive Concerns After Cancer Scale (RCAC).

BACKGROUND: Improving cancer survival rates highlights post-treatment fertility implications for reproductive-aged women. To provide fertility care for cancer survivors, nurses need instruments to assess and communicate reproductive concerns with cancer survivors and healthcare providers. This study aimed to translate the Reproductive Concerns after Cancer Scale (RCAC) into Korean and examine its psychometric properties in young female cancer survivors in South Korea. METHODS: The RCAC was translated into Korean, involving expert bilingual translators for initial translation and reverse translation for cultural and semantic accuracy. In detail, the RCAC was translated into Korean and evaluated in a preliminary study involving 10 cancer survivors. Subsequently, a revised version of the instrument was administered to 182 cancer survivors and a psychometric evaluation was conducted. The process included verifying content validity, and then assessing construct validity using exploratory factor analysis and criterion validity. The reliability of the instrument was quantified by measuring its internal consistency using Cronbach's alpha. RESULTS: The translated RCAC demonstrated an item-level content validity index of 1.0 and a scale-level index of 1.0. The content was finalized based on preliminary survey findings, which revealed that all participants thought the instrument was clear. The Korean version of the RCAC demonstrated a satisfactory level of validity per exploratory factor analysis, which resulted in a 14-item instrument consisting of three subscales: "fertility potential" (six items), "health problem" (five items), and "acceptance" (three items). The items and subscales explained 57.6% of the variance. Criterion validity was confirmed through an analysis of the correlation between the Korean version of the RCAC and both the FACT-G (r = -0.36, p < .001) and PHQ-9 (r = 0.38, p < .001). Cronbach's alpha coefficient of the Korean version of the RCAC was 0.83. CONCLUSIONS: The Korean version of the RCAC is a valid and reliable instrument for assessing reproductive concerns in female cancer survivors. Thus, this instrument can be used to provide tailored care to female cancer survivors of reproductive age by clarifying and assess their reproductive concerns. This may support the development of guidelines or policies to provide care for those with reproductive concerns who require nursing care.

Associations of Perioperative Red Blood Cell Transfusion With Outcomes of Kidney Transplantation in Korea Over a 16-Year Period.

BACKGROUND: This study investigated the associations between transfusion of different types of red blood cell (RBC) preparations and kidney allograft outcomes after kidney transplantation (KT) over a 16-year period in Korea using a nationwide population-based cohort. METHODS: We investigated the reported use of RBCs during hospitalization for KT surgery, rejection, and graft failure status using nationwide data from the National Health Information Database (2002-2017). The associations between the type of perioperative RBC product and transplant outcomes were evaluated among four predefined groups: no RBC transfusion, filtered RBCs, washed RBCs, and packed RBCs (pRBCs). RESULTS: A total of 17,754 KT patients was included, among which 8,530 (48.0%) received some type of RBC transfusion. Of the patients who received RBC transfusion, 74.9%, 19.7%, and 5.4% received filtered RBCs, pRBCs, or washed RBCs, respectively. Regardless of the type of RBC products, the proportions of acute rejection and graft failure was significantly greater in patients receiving transfusion (P < 0.001). Cox proportional hazards regression analyses showed that the filtered RBC and pRBC groups were significantly associated with both rejection and graft failure. The washed RBC group also had hazard ratios greater than 1.0 for rejection and graft failure, but the association was not significant. Rejection-free survival of the pRBC group was significantly lower than that of the other groups (P < 0.001, log-rank test), and graft survival for the no RBC transfusion group was significantly greater than in the other groups (P < 0.001, log-rank test). CONCLUSION: Perioperative RBC transfusion was associated with poor graft outcomes. Notably, transfusion of pRBCs significantly increased transplant rejection. Therefore, careful consideration of indications for RBC transfusion and selection of the appropriate type of RBCs is necessary, especially for patients at high risk of rejection or graft failure.

Use of Antibiotics Within the Last 14 Days of Life in Korean Patients: A Nationwide Study.

BACKGROUND: Antimicrobial prescriptions for serious chronic or acute illness nearing its end stages raise concerns about the potential for futile use, adverse events, increased multidrug-resistant organisms, and significant patient and social cost burdens. This study investigated the nationwide situation of how antibiotics are prescribed to patients during the last 14 days of life to guide future actions. METHODS: This nationwide multicenter retrospective cohort study was conducted at 13 hospitals in South Korea from November 1 to December 31, 2018. All decedents were included in the study. Antibiotic use during the last two weeks of their lives was investigated. RESULTS: A total of 1,201 (88.9%) patients received a median of two antimicrobial agents during the last two weeks of their lives. Carbapenems were prescribed to approximately half of the patients (44.4%) in the highest amount (301.2 days of therapy per 1,000 patient-days). Among the patients receiving antimicrobial agents, 63.6% were inappropriate and only 327 patients (27.2%) were referred by infectious disease specialists. The use of carbapenem (odds ratio [OR], 1.51; 95% confidence interval [CI], 1.13-2.03; P = 0.006), underlying cancer (OR, 1.56; 95% CI, 1.20-2.01, P = 0.047), underlying cerebrovascular disease (OR, 1.88; 95% CI, 1.23-2.89, P = 0.004), and no microbiological testing (OR, 1.79; 95% CI, 1.15-2.73; P = 0.010) were independent predictors for inappropriate antibiotic prescribing. CONCLUSION: A considerable number of antimicrobial agents are administered to patients with chronic or acute illnesses nearing their end-of-life, a high proportion of which are prescribed inappropriately. Consultation with an infectious disease specialist, in addition to an antimicrobial stewardship program, may be necessary to induce the optimal use of antibiotics.

Xerostomia and Its Cellular Targets.

Xerostomia, the subjective feeling of a dry mouth associated with dysfunction of the salivary glands, is mainly caused by radiation and chemotherapy, various systemic and autoimmune diseases, and drugs. As saliva plays numerous essential roles in oral and systemic health, xerostomia significantly reduces quality of life, but its prevalence is increasing. Salivation mainly depends on parasympathetic and sympathetic nerves, and the salivary glands responsible for this secretion move fluid unidirectionally through structural features such as the polarity of acinar cells. Saliva secretion is initiated by the binding of released neurotransmitters from nerves to specific G-protein-coupled receptors (GPCRs) on acinar cells. This signal induces two intracellular calcium (Ca2+) pathways (Ca2+ release from the endoplasmic reticulum and Ca2+ influx across the plasma membrane), and this increased intracellular Ca2+ concentration ([Ca2+]i) causes the translocation of the water channel aquaporin 5 (AQP5) to the apical membrane. Consequently, the GPCR-mediated increased [Ca2+]i in acinar cells promotes saliva secretion, and this saliva moves into the oral cavity through the ducts. In this review, we seek to elucidate the potential of GPCRs, the inositol 1,4,5-trisphosphate receptor (IP3R), store-operated Ca2+ entry (SOCE), and AQP5, which are essential for salivation, as cellular targets in the etiology of xerostomia.

Activity-induced synaptic structural modifications by Akt.

The activity-dependent regulation of synaptic structures plays a key role in synaptic development and plasticity; however, the signaling mechanisms involved remain largely unknown. The serine/threonine protein kinase Akt, a downstream effector of phosphoinositide 3-kinase (PI3K), plays a pivotal role in a wide range of physiological functions. We focused on the importance of Akt in rapid synaptic structural changes after stimulation at the Drosophila neuromuscular junction, a well-studied model synapse. Compared with wild-type larvae, akt mutants showed significantly reduced muscle size and an increased number of boutons per area, suggesting that Akt is required for proper pre- and postsynaptic growth. In addition, the level of cysteine string protein (CSP) was significantly increased, and its distribution was different in akt mutants. After high K+ single stimulation, the CSP level of akt mutant NMJs increased dramatically compared with that of wild-type NMJs. Interestingly, ghost boutons without postsynaptic specialization were found in akt mutant NMJs, and the number of these boutons was significantly increased by patterned stimulation. In contrast, the postsynaptic change in the subsynaptic reticulum (SSR) in the akt mutant occurred independent of stimulation. These results suggest that Akt functions in both pre- and postsynaptic growth and differentiation, and in particular, presynaptic action occurs in an activity-dependent manner.

Caspase-10 affects the pathogenesis of primary biliary cholangitis by regulating inflammatory cell death.

Primary biliary cholangitis (PBC) is an autoimmune disease that involves chronic inflammation and injury to biliary epithelial cells. To identify critical genetic factor(s) in PBC patients, we performed whole-exome sequencing of five female siblings, including one unaffected and four affected sisters, in a multi-PBC family, and identified 61 rare heterozygote variants that segregated only within the affected sisters. Among them, we were particularly interested in caspase-10, for although several caspases are involved in cell death, inflammation and autoimmunity, caspase-10 is little known from this perspective. We generated caspase-10 knockout macrophages, and then investigated the obtained phenotypes in comparison to those of its structurally similar protein, caspase-8. Unlike caspase-8, caspase-10 does not play a role during differentiation into macrophages, but after differentiation, it regulates the process of inflammatory cell deaths such as necroptosis and pyroptosis more strongly. Interestingly, caspase-10 displays better protease activity than caspase-8 in the process of RIPK1 cleavage, and an enhanced ability to form a complex with RIPK1 and FADD in human macrophages. Higher inflammatory cell death affected the fibrotic response of hepatic stellate cells; this effect could be recovered by treatment with UDCA and OCA, which are currently approved for PBC patients. Our findings strongly indicate that the defective roles of caspase-10 in macrophages contribute to the pathogenesis of PBC, thereby suggesting a new therapeutic strategy for PBC treatment.

Application of CRISPR/Cas9-based mutant enrichment technique to improve the clinical sensitivity of plasma EGFR testing in patients with non-small cell lung cancer.

BACKGROUND: Approximately 50%-60% of secondary resistance to primary EGFR- tyrosine kinase inhibitors (TKI) therapy is caused by acquired p.Thr790Met (T790M) mutation; however, highly fragmented, low-quantity circulating tumor DNA is an obstacle for detecting mutations. Therefore, more sensitive mutation detection techniques are required. Here, we report a new mutant enrichment technology, the CRISPR system combined with post-polymerase chain reaction (PCR) cell-free DNA (cfDNA) (CRISPR-CPPC) to detect the T790M mutation using droplet digital PCR (ddPCR) from cfDNA. METHODS: The CRISPR-CPPC process comprises the following three steps: (1) cfDNA PCR, (2) assembly of post-PCR cfDNA and CRISPR/CRISPR associated protein 9 complex, and (3) enrichment of the target DNA template. After CRISPR-CPPC, the target DNA was detected using ddPCR. We optimized and validated CRISPR-CPPC using reference cfDNA standards and cfDNA from patients with non-small cell lung cancer who underwent TKI therapy. We then compared the detection sensitivity of CRISPR-CPPC assay with the results of real-time PCR and those of ddPCR. RESULTS: CRISPR-CPPC aided detection of T790M with 93.9% sensitivity and 100% specificity. T790M mutant copies were sensitively detected achieving an approximately 13-fold increase in the detected allele frequency. Furthermore, positive rate of detecting a low T790M copy number (< 10 copies/mL) were 93.8% (15/16) and 43.8% (7/16) for CRISPR-CPPC assay and ddPCR, respectively. CONCLUSIONS: CRISPR-CPPC is a useful mutant enrichment tool for the sensitive detection of target mutation. When tested in patients with progressive disease, the diagnostic performance of CRISPR-CPPC assay is exceptionally better than that of any other currently available methods.

Post-acute COVID-19 syndrome in patients after 12 months from COVID-19 infection in Korea.

BACKGROUND: As the coronavirus disease 2019 (COVID-19) pandemic continues to progress, awareness about its long-term impacts has been growing. To date, studies on the long-term course of symptoms, factors associated with persistent symptoms, and quality of life after 12 months since recovery from acute COVID-19 have been limited. METHODS: A prospective online survey (First: September 8, 2020-September 10, 2020; Second: May 26, 2021-June 1, 2021) was conducted on recovered patients who were previously diagnosed with COVID-19 between February 13, 2020 and March 13, 2020 at Kyungpook National University Hospital. Responders aged between 17 and 70 years were included in the study. Overall, 900 and 241 responders were followed up at 6 and 12 months after recovery from COVID-19 in the first and second surveys, respectively. Clinical characteristics, self-reported persistent symptoms, and EuroQol-5-dimension (EQ5D) index score were investigated for evaluating quality of life. RESULTS: The median period from the date of the first symptom onset or COVID-19 diagnosis to the time of the survey was 454 (interquartile range [IQR] 451-458) days. The median age of the responders was 37 (IQR 26.0-51.0) years, and 164 (68.0%) responders were women. Altogether, 11 (4.6%) responders were asymptomatic, and 194 (80.5%), 30 (12.4%), and 6 (2.5%) responders had mild, moderate, and severe illness, respectively. Overall, 127 (52.7%) responders still experienced COVID-19-related persistent symptoms and 12 (5.0%) were receiving outpatient treatment for such symptoms. The main symptoms were difficulty in concentration, cognitive dysfunction, amnesia, depression, fatigue, and anxiety. Considering the EQ5D index scores, only 59.3% of the responders did not have anxiety or depression. Older age, female sex, and disease severity were identified as risk factors for persistent neuropsychiatric symptoms. CONCLUSION: COVID-19-related persistent symptoms improved over time; however, neurological symptoms can last longer than other symptoms. Continuous careful observation of symptom improvement and multidisciplinary integrated research on recovered COVID-19 patients are required.

The effect of the multimodal intervention including an automatic notification of catheter days on reducing central line-related bloodstream infection: a retrospective, observational, quasi-experimental study.

BACKGROUND: A central venous catheter (CVC) is an important medical device, but it could be preceding infection and the risk of central line-associated bloodstream infection (CLABSI). CLABSI is a common healthcare-associated infection but results in high cost and mortality; therefore, various efforts to reduce CLABSI have been attempted. METHODS: This is a retrospective, observational, quasi-experimental study in the intensive care unit (ICU) of a single tertiary care hospital. We reviewed and analysed the data of CLABSI rates and days from the insertion to the removal of the temporary CVC between January 2018 and June 2021 with transient periods over 9 months. Sequentially, all patients with the CVC in the ICU underwent the following interventions: maximal barrier precaution, automatic notification of catheter days and 2% chlorhexidine gluconate bathing. A segmented regression analysis of interrupted time series was conducted to compare the CLABSI rates before and after the introduction of multimodal interventions. During study periods, the impact of interventions on CLABSI was evaluated using multivariate logistic regression analyses. RESULTS: A total of 76,504 patient-days, 28,312 catheter days and 66 CLABSI cases were reviewed in ICU-hospitalised patients. As additional interventions, the CLABSI rate declined from 3.1 per 1000 CVC days to 1.2 per 1000 CVC days in post-interventions. In the pre-intervention and post-intervention periods, 4146 patents had one more short-term CVC. In the multivariate logistic regression analyses, multimodal intervention was one of determinants reducing CLABSI rates (odds ratio (OR), 0.52 [95% confidence interval {CI}, 0.28-0.94]). Indwelling time of CVC over 10 days was the risk factor for CLABSI rates (OR, 6.27 [95% CI, 3.36-12.48]). Of the three interventions, the automatic notification of catheter days was associated with decreased median monthly total CVC days and duration of CVC days per patient. CONCLUSIONS: Multidisciplinary and evidence-based interventions could lead to a decrease in the CLABSI rates. Moreover, the automatic notification of catheter days of the electronic medical healthcare system has shortened the time of indwelling CVC.

Optimum Urine Cotinine and NNAL Levels to Distinguish Smokers from Non-Smokers by the Changes in Tobacco Control Policy in Korea from 2008 to 2018.

INTRODUCTION: We examined the age- and sex-specific distributions of biomarkers of tobacco smoke exposure to determine the optimal cutoffs to distinguish smokers from non-smokers over the last 10 years in Korea, during which smoking prevalence and secondhand smoke (SHS) exposure declined due to changes in tobacco control policy. METHODS: We analyzed data from the Korea National Health and Nutrition Examination Survey on creatinine-adjusted urinary cotinine (2008-2018; 33 429 adults: 15 653 males and 17 776 females) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL; 2016-2018; 6337 adults: 3091 males and 3246 females). We determined the optimal cutoffs and confidence intervals (CIs) to distinguish smokers from non-smokers using receiver operator characteristic curve analysis and bootstrapping (1000 resamples). RESULTS: The optimal cutoff values of creatinine-adjusted urine cotinine and NNAL concentration were 20.9 ng/mg (95% CI: 20.8-21.0, sensitivity: 96.6%, specificity: 93.8%) and 8.9 pg/mg (95% CI: 8.8-8.9, sensitivity: 94.0%, specificity: 94.7%), respectively, in 2016-2018. The optimal cutoffs of both biomarkers increased with age and were higher in females than in males for NNAL concentration. In both sexes, the optimal cutoff of urine cotinine continuously declined over the study period. CONCLUSIONS: The optimal cotinine cutoff declined along with smoking prevalence and levels of SHS exposure due to enforcement of tobacco control policies, including smoke-free ordinances and tax increases. Monitoring of biomarkers of tobacco exposure appears necessary for verification of smoking status and regulatory use. IMPLICATIONS: Our results based on nationally representative data suggest that a large decrease in the optimal cutoff value of urine cotinine to distinguish smokers from non-smokers was caused by decreases in smoking prevalence and SHS exposure following enforcement of tobacco control policies over the last 10 years. We determined the optimal cutoff values of urine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), which were not previously reported in representative population in Asia, to enable more accurate estimation of exposure to tobacco smoke and proper assessment of disease risks. Gender- and age-specific differences in the optimal cutoffs require further study. Monitoring of biomarkers of tobacco smoke exposure seems necessary for verification of smoking status and regulatory use.