Purpose: The association between the fecal microbiota and colorectal cancer (CRC) risk has been suggested in epidemiologic studies. However, data from large-scale population-based studies are lacking. Materials and Methods: In this case-control study, we recruited 283 CRC patients from the Center for Colorectal Cancer, National Cancer Center Hospital, Korea to perform 16S rRNA gene sequencing of fecal samples. A total of 283 age- and sex-matched healthy participants were selected from 890 cohort of healthy Koreans that are publicly available (PRJEB33905). The microbial dysbiosis index (MDI) was calculated based on the differentially abundant species. The association between MDI and CRC risk was observed using conditional logistic regression. Sparse Canonical Correlation Analysis was performed to integrate species data with microbial pathways obtained by PICRUSt2. Results: There is a significant divergence of the microbial composition between CRC patients and controls (permutational multivariate analysis of variance p=0.001). Those who were in third tertile of the MDI showed a significantly increased risk of CRC in the total population (odds ratio [OR], 6.93; 95% confidence interval [CI], 3.98 to 12.06; p-trend < 0.001) compared to those in the lowest tertile. Similar results were found for men (OR, 6.28; 95% CI, 3.04 to 12.98; p-trend < 0.001) and women (OR, 7.39; 95% CI, 3.10 to 17.63; p-trend < 0.001). Bacteroides coprocola and Bacteroides plebeius species and 12 metabolic pathways were interrelated in healthy controls that explain 91% covariation across samples. Conclusion Dysbiosis in the fecal microbiota may be associated with an increased risk of CRC. Due to the potentially modifiable nature of the gut microbiota, our findings may have implications for CRC prevention among Koreans.

Purpose: The association between the fecal microbiota and colorectal cancer (CRC) risk has been suggested in epidemiologic studies. However, data from large-scale population-based studies are lacking. Materials and Methods: In this case-control study, we recruited 283 CRC patients from the Center for Colorectal Cancer, National Cancer Center Hospital, Korea to perform 16S rRNA gene sequencing of fecal samples. A total of 283 age- and sex-matched healthy participants were selected from 890 cohort of healthy Koreans that are publicly available (PRJEB33905). The microbial dysbiosis index (MDI) was calculated based on the differentially abundant species. The association between MDI and CRC risk was observed using conditional logistic regression. Sparse Canonical Correlation Analysis was performed to integrate species data with microbial pathways obtained by PICRUSt2. Results: There is a significant divergence of the microbial composition between CRC patients and controls (permutational multivariate analysis of variance p=0.001). Those who were in third tertile of the MDI showed a significantly increased risk of CRC in the total population (odds ratio [OR], 6.93; 95% confidence interval [CI], 3.98 to 12.06; p-trend < 0.001) compared to those in the lowest tertile. Similar results were found for men (OR, 6.28; 95% CI, 3.04 to 12.98; p-trend < 0.001) and women (OR, 7.39; 95% CI, 3.10 to 17.63; p-trend < 0.001). Bacteroides coprocola and Bacteroides plebeius species and 12 metabolic pathways were interrelated in healthy controls that explain 91% covariation across samples. Conclusion Dysbiosis in the fecal microbiota may be associated with an increased risk of CRC. Due to the potentially modifiable nature of the gut microbiota, our findings may have implications for CRC prevention among Koreans.

Purpose: The association between the fecal microbiota and colorectal cancer (CRC) risk has been suggested in epidemiologic studies. However, data from large-scale population-based studies are lacking. Materials and Methods: In this case-control study, we recruited 283 CRC patients from the Center for Colorectal Cancer, National Cancer Center Hospital, Korea to perform 16S rRNA gene sequencing of fecal samples. A total of 283 age- and sex-matched healthy participants were selected from 890 cohort of healthy Koreans that are publicly available (PRJEB33905). The microbial dysbiosis index (MDI) was calculated based on the differentially abundant species. The association between MDI and CRC risk was observed using conditional logistic regression. Sparse Canonical Correlation Analysis was performed to integrate species data with microbial pathways obtained by PICRUSt2. Results: There is a significant divergence of the microbial composition between CRC patients and controls (permutational multivariate analysis of variance p=0.001). Those who were in third tertile of the MDI showed a significantly increased risk of CRC in the total population (odds ratio [OR], 6.93; 95% confidence interval [CI], 3.98 to 12.06; p-trend < 0.001) compared to those in the lowest tertile. Similar results were found for men (OR, 6.28; 95% CI, 3.04 to 12.98; p-trend < 0.001) and women (OR, 7.39; 95% CI, 3.10 to 17.63; p-trend < 0.001). Bacteroides coprocola and Bacteroides plebeius species and 12 metabolic pathways were interrelated in healthy controls that explain 91% covariation across samples. Conclusion Dysbiosis in the fecal microbiota may be associated with an increased risk of CRC. Due to the potentially modifiable nature of the gut microbiota, our findings may have implications for CRC prevention among Koreans.

Background: This study aimed to investigate the erosive potential of powdered vitamin C on the bovine enamel tooth surface. Methods: The experiment included five groups: Lemona, Vitagran, Korea Eundan, Coca-Cola (positive controls), and artificialsaliva (negative controls). The pH and titratable acidity were measured. Bovine enamel specimens were immersed in the experimental solutions for 15 minutes each day for 7 days. The surface microhardness was measured using the Vickers hardness number before immersion and on the 1st, 3rd, 5th, and 7th days. The surfaces of the bovine enamel specimens were observed by scanning electron microscopy (SEM). Results: The pH of the experimental groups was as follows: Lemona (2.04±0.04) had the lowest pH, followed by Vitagran(2.56±0.01), the positive control group Coca-Cola (2.60±0.03), Korea Eundan (3.14±0.02), and the negative control group artificial saliva (7.06±0.05). Surface microhardness decreased significantly during the immersion period (p＜0.001). The largest surface microhardness reduction value was shown in Lemona (–201.22±20.60), followed by Vitagran (–190.02±14.73), Korea Eundan (–189.27±27.14), Coca-Cola (–99.28±17.21), artificial saliva (–10.99±9.94). According to the SEM findings, the experimental and positive control groups exhibited rough surfaces with micropores, whereas the negative control group exhibited smooth surfaces before specimen immersion. Conclusion Consuming powdered vitamin C at a low pH may degrade the enamel surface. To reduce the erosive effect, it isrecommended to rinse the mouth with water and brush the teeth after an hour.

Background: This study aimed to investigate the erosive potential of powdered vitamin C on the bovine enamel tooth surface. Methods: The experiment included five groups: Lemona, Vitagran, Korea Eundan, Coca-Cola (positive controls), and artificialsaliva (negative controls). The pH and titratable acidity were measured. Bovine enamel specimens were immersed in the experimental solutions for 15 minutes each day for 7 days. The surface microhardness was measured using the Vickers hardness number before immersion and on the 1st, 3rd, 5th, and 7th days. The surfaces of the bovine enamel specimens were observed by scanning electron microscopy (SEM). Results: The pH of the experimental groups was as follows: Lemona (2.04±0.04) had the lowest pH, followed by Vitagran(2.56±0.01), the positive control group Coca-Cola (2.60±0.03), Korea Eundan (3.14±0.02), and the negative control group artificial saliva (7.06±0.05). Surface microhardness decreased significantly during the immersion period (p＜0.001). The largest surface microhardness reduction value was shown in Lemona (–201.22±20.60), followed by Vitagran (–190.02±14.73), Korea Eundan (–189.27±27.14), Coca-Cola (–99.28±17.21), artificial saliva (–10.99±9.94). According to the SEM findings, the experimental and positive control groups exhibited rough surfaces with micropores, whereas the negative control group exhibited smooth surfaces before specimen immersion. Conclusion Consuming powdered vitamin C at a low pH may degrade the enamel surface. To reduce the erosive effect, it isrecommended to rinse the mouth with water and brush the teeth after an hour.

Background: This study aimed to investigate the erosive potential of powdered vitamin C on the bovine enamel tooth surface. Methods: The experiment included five groups: Lemona, Vitagran, Korea Eundan, Coca-Cola (positive controls), and artificialsaliva (negative controls). The pH and titratable acidity were measured. Bovine enamel specimens were immersed in the experimental solutions for 15 minutes each day for 7 days. The surface microhardness was measured using the Vickers hardness number before immersion and on the 1st, 3rd, 5th, and 7th days. The surfaces of the bovine enamel specimens were observed by scanning electron microscopy (SEM). Results: The pH of the experimental groups was as follows: Lemona (2.04±0.04) had the lowest pH, followed by Vitagran(2.56±0.01), the positive control group Coca-Cola (2.60±0.03), Korea Eundan (3.14±0.02), and the negative control group artificial saliva (7.06±0.05). Surface microhardness decreased significantly during the immersion period (p＜0.001). The largest surface microhardness reduction value was shown in Lemona (–201.22±20.60), followed by Vitagran (–190.02±14.73), Korea Eundan (–189.27±27.14), Coca-Cola (–99.28±17.21), artificial saliva (–10.99±9.94). According to the SEM findings, the experimental and positive control groups exhibited rough surfaces with micropores, whereas the negative control group exhibited smooth surfaces before specimen immersion. Conclusion Consuming powdered vitamin C at a low pH may degrade the enamel surface. To reduce the erosive effect, it isrecommended to rinse the mouth with water and brush the teeth after an hour.

Background: Worldwide, sepsis is the leading cause of death in hospitals. If mortality rates in patients with sepsis can be predicted early, medical resources can be allocated efficiently. We constructed machine learning (ML) models to predict the mortality of patients with sepsis in a hospital emergency department. Methods: This study prospectively collected nationwide data from an ongoing multicenter cohort of patients with sepsis identified in the emergency department. Patients were enrolled from 19 hospitals between September 2019 and December 2020. For acquired data from 3,657 survivors and 1,455 deaths, six ML models (logistic regression, support vector machine, random forest, extreme gradient boosting [XGBoost], light gradient boosting machine, and categorical boosting [CatBoost]) were constructed using fivefold cross-validation to predict mortality. Through these models, 44 clinical variables measured on the day of admission were compared with six sequential organ failure assessment (SOFA) components (PaO 2 /FIO 2 [PF], platelets (PLT), bilirubin, cardiovascular, Glasgow Coma Scale score, and creatinine).The confidence interval (CI) was obtained by performing 10,000 repeated measurements via random sampling of the test dataset. All results were explained and interpreted using Shapley’s additive explanations (SHAP). Results: Of the 5,112 participants, CatBoost exhibited the highest area under the curve (AUC) of 0.800 (95% CI, 0.756–0.840) using clinical variables. Using the SOFA components for the same patient, XGBoost exhibited the highest AUC of 0.678 (95% CI, 0.626–0.730). As interpreted by SHAP, albumin, lactate, blood urea nitrogen, and international normalization ratio were determined to significantly affect the results. Additionally, PF and PLTs in the SOFA component significantly influenced the prediction results. Conclusion Newly established ML-based models achieved good prediction of mortality in patients with sepsis. Using several clinical variables acquired at the baseline can provide more accurate results for early predictions than using SOFA components. Additionally, the impact of each variable was identified.

Background: Limited data are available on the mortality rates of patients receiving extracorporeal membrane oxygenation (ECMO) support for coronavirus disease 2019 (COVID-19). We aimed to analyze the relationship between COVID-19 and clinical outcomes for patients receiving ECMO. Methods: We retrospectively investigated patients with COVID-19 pneumonia requiring ECMO in 19 hospitals across Korea from January 1, 2020 to August 31, 2021. The primary outcome was the 90-day mortality after ECMO initiation. We performed multivariate analysis using a logistic regression model to estimate the odds ratio (OR) of 90-day mortality. Survival differences were analyzed using the Kaplan–Meier (KM) method. Results: Of 127 patients with COVID-19 pneumonia who received ECMO, 70 patients (55.1%) died within 90 days of ECMO initiation. The median age was 64 years, and 63% of patients were male. The incidence of ECMO was increased with age but was decreased after 70 years of age. However, the survival rate was decreased linearly with age. In multivariate analysis, age (OR, 1.048; 95% confidence interval [CI], 1.010–1.089; P = 0.014) and receipt of continuous renal replacement therapy (CRRT) (OR, 3.069; 95% CI, 1.312–7.180; P = 0.010) were significantly associated with an increased risk of 90-day mortality. KM curves showed significant differences in survival between groups according to age (65 years) (log-rank P = 0.021) and receipt of CRRT (log-rank P = 0.004). Conclusion Older age and receipt of CRRT were associated with higher mortality rates among patients with COVID-19 who received ECMO.

Background: and Purpose Tenecteplase is a thrombolytic agent with pharmacological advantages over alteplase and has been shown to be noninferior to alteplase for acute ischemic stroke in randomized trials. However, evidence pertaining to the safety and efficacy of tenecteplase in patients from different ethnic groups is lacking. The aim of this systematic review and metaanalysis was to investigate ethnicity-specific differences in the safety and efficacy of tenecteplase versus alteplase in patients with acute ischemic stroke. Methods: Following an International Prospective Register of Systematic Reviews (PROSPERO)- registered protocol (CRD42023475038), three authors conducted a systematic review of the PubMed/MEDLINE, Embase, Cochrane Library, and CINAHL databases for articles comparing the use of tenecteplase with any thrombolytic agent in patients with acute ischemic stroke up to November 20, 2023. The certainty of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework. Two independent authors extracted data onto a standardized data collection sheet. A pairwise meta-analysis was conducted in risk ratios (RR). Results: From 34 studies (59,601 participants), the rate of complete recanalization was significantly higher (P<0.01) in Asian (RR: 1.91, 95% confidence interval [CI]: 1.30 to 2.80) versus Caucasian patients (RR: 0.99, 95% CI: 0.87 to 1.14). However, Asian patients (RR: 1.18, 95% CI: 0.87 to 1.62) had significantly higher (P=0.01) rates of mortality compared with Caucasian patients (RR: 1.10, 95% CI: 1.00 to 1.22). Caucasian patients were also more likely to attain a modified Rankin Scale (mRS) score of 0 to 2 at follow-up (RR: 1.14, 95% CI, 1.10 to 1.19) compared with Asian (RR: 1.00, 95% CI, 0.95 to 1.05) patients. There was no significant difference in the rate of symptomatic intracranial hemorrhage (P=0.20) and any intracranial hemorrhage (P=0.83) between Asian and Caucasian patients. Conclusion Tenecteplase was associated with significantly higher rates of complete recanalization in Asian patients compared with Caucasian patients. However, tenecteplase was associated with higher rates of mortality and lower rates of mRS 0 to 2 in Asian patients compared with Caucasian patients. It may be beneficial to study the variations in response to tenecteplase among patients of different ethnic groups in large prospective cohort studies.

Purpose: Due to the shortage of lung donors relative to the number of patients waiting for lung transplantation (LTx), more than one-third of patients on the waitlist have died without receiving LTx in Korea. Therefore, the importance of fair and effective allocation policies has been emphasized. This study investigated the characteristics of the current urgency-based allocation system in Korea by simulating the Eurotransplant lung allocation score (ET-LAS) using a nationwide multi-institutional registry for LTx in Korea. Materials and Methods: This study used data from the Korean Organ Transplantation Registry (KOTRY), along with additional retrospective data for ET-LAS calculation. A total of 194 patients were included in this study between January 2015 and December 2019. The Korean urgency definition classifies an LTx candidate as having statuses 0–3 according to urgency. The ET-LAS was analyzed according to the Korean urgency status. Results: In total, 92 patients received lung transplants at status 0, 85 at status 1, and 17 at status 2/3. The ET-LAS showed a bimodal distribution with distinct peaks corresponding to status 0 and non-status 0. There was no significant difference in the ET-LAS among non-status 0 patients. In logistic and decision tree analyses, oxygen supplementation methods, particularly oxygen masks and high-flow nasal cannulas, were significantly associated with a high ET-LAS (≥50) among non-status 0 patients. Conclusion Simulation of the ET-LAS with KOTRY data showed that the Korean urgency definition may not allocate lungs by urgency, especially for patients in non-status 0; therefore, it needs to be revised.