Background: This study aimed to evaluate the applicability of deep learning technology to thyroid ultrasound images for classification of thyroid nodules. Methods: This retrospective analysis included ultrasound images of patients with thyroid nodules investigated by fine-needle aspiration at the thyroid clinic of a single center from April 2010 to September 2012. Thyroid nodules with cytopathologic results of Bethesda category V (suspicious for malignancy) or VI (malignant) were defined as thyroid cancer. Multiple deep learning algorithms based on convolutional neural networks (CNNs) —ResNet, DenseNet, and EfficientNet—were utilized, and Siamese neural networks facilitated multi-view analysis of paired transverse and longitudinal ultrasound images. Results: Among 1,048 analyzed thyroid nodules from 943 patients, 306 (29%) were identified as thyroid cancer. In a subgroup analysis of transverse and longitudinal images, longitudinal images showed superior prediction ability. Multi-view modeling, based on paired transverse and longitudinal images, significantly improved the model performance; with an accuracy of 0.82 (95% confidence intervals [CI], 0.80 to 0.86) with ResNet50, 0.83 (95% CI, 0.83 to 0.88) with DenseNet201, and 0.81 (95% CI, 0.79 to 0.84) with EfficientNetv2_ s. Training with high-resolution images obtained using the latest equipment tended to improve model performance in association with increased sensitivity. Conclusion CNN algorithms applied to ultrasound images demonstrated substantial accuracy in thyroid nodule classification, indicating their potential as valuable tools for diagnosing thyroid cancer. However, in real-world clinical settings, it is important to aware that model performance may vary depending on the quality of images acquired by different physicians and imaging devices.

Background: and Purpose Treatments for neuromyelitis optica spectrum disorder (NMOSD) such as eculizumab, ravulizumab, satralizumab, and inebilizumab have significantly advanced relapse prevention, but they remain expensive. Rituximab is an off-label yet popular alternative that offers a cost-effective solution, but its real-world efficacy needs better quantification for guiding the application of newer approved NMOSD treatments (ANTs). This study aimed to determine real-world rituximab failure rates to anticipate the demand for ANTs and aid in resource allocation. Methods: We conducted a nationwide retrospective study involving 605 aquaporin-4-antibody-positive NMOSD patients from 22 centers in South Korea that assessed the efficacy and safety of rituximab over a median follow-up of 47 months. Results: The 605 patients treated with rituximab included 525 (87%) who received continuous therapy throughout the follow-up period (median=47 months, interquartile range=15–87 months). During this period, 117 patients (19%) experienced at least 1 relapse. Notably, 68 of these patients (11% of the total cohort) experienced multiple relapses or at least 1 severe relapse.Additionally, 2% of the patients discontinued rituximab due to adverse events, which included severe infusion reactions, neutropenia, and infections. Conclusions This study has confirmed the efficacy of rituximab in treating NMOSD, as evidenced by an 87% continuation rate among patients over a 4-year follow-up period. Nevertheless, the occurrence of at least one relapse in 19% of the cohort, including 11% who experienced multiple or severe relapses, and a 2% discontinuation rate due to adverse events highlight the urgent need for alternative therapeutic options.

Purpose: Despite extensive research on gastric cancer (GC), efforts to consolidate the numerous associations between possible factors and GC risk remain lacking. This systematic review aimed to provide an overview of potential GC-associated pairs. Materials and Methods: We systematically searched PubMed, Embase, and Cochrane databases, from their inception to April 23, 2022, for eligible systematic reviews and metaanalyses to investigate the association between any possible factors and GC risk. After the inclusion of 75 systematic reviews and meta-analyses, 117 association pairs were examined. We reanalyzed the included meta-analyses and produced effect estimates using uniform analytical models. The certainty of the evidence for each association pair was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) criteria. Results: Iatrogenic factors, including antibacterial drugs, were associated with an increased risk of GC. Epstein-Barr virus and Helicobacter pylori infections were also associated with an increased risk of GC, while human T-lymphotropic virus type 1 (HTLV-1) infections were associated with a reduced risk. Dietary habit was a major factor influencing moderate to high GRADE associations. Positive associations were observed for heavy alcohol consumption (relative risk [RR], 1.13; 95% confidence interval [CI], 1.06–1.12), refined grain consumption (RR, 1.36; 95% CI, 1.21–1.53), and habitual salt intake (RR, 1.41; 95% CI, 1.04–1.91). Conclusions The associations between GC risk and dietary and nutritional factors were considerably heterogeneous, whereas other factors, such as lifestyle and iatrogenic and environmental exposures, were consistent across regions. Therefore, dietary interventions for GC prevention should be tailored specific to regions.

Background: The accuracy of Logical Observation Identifiers Names and Codes (LOINC) mappings is reportedly low, and the LOINC codes used for research purposes in Korea have not been validated for accuracy or usability. Our study aimed to evaluate the discrepancies and similarities in interoperability using existing LOINC mappings in actual patient care settings. Methods: We collected data on local test codes and their corresponding LOINC mappings from seven university hospitals. Our analysis focused on laboratory tests that are frequently requested, excluding clinical microbiology and molecular tests. Codes from nationwide proficiency tests served as intermediary benchmarks for comparison. A research team, comprising clinical pathologists and terminology experts, utilized the LOINC manual to reach a consensus on determining the most suitable LOINC codes. Results: A total of 235 LOINC codes were designated as optimal codes for 162 frequent tests.Among these, 51 test items, including 34 urine tests, required multiple optimal LOINC codes, primarily due to unnoted properties such as whether the test was quantitative or qualitative, or differences in measurement units. We analyzed 962 LOINC codes linked to 162 tests across seven institutions, discovering that 792 (82.3%) of these codes were consistent. Inconsistencies were most common in the analyte component (38 inconsistencies, 33.3%), followed by the method (33 inconsistencies, 28.9%), and properties (13 inconsistencies, 11.4%). Conclusion This study reveals a significant inconsistency rate of over 15% in LOINC mappings utilized for research purposes in university hospitals, underlining the necessity for expert verification to enhance interoperability in real patient care.

Background: and Purpose The Treat Stroke to Target (TST) was a randomized clinical trial involving French and Korean patients demonstrating that a lower low-density lipoprotein cholesterol (LDL-C, <70 mg/dL) target group (LT) experienced fewer cerebro-cardiovascular events than a higher target (90–110 mg/dL) group (HT). However, whether these results can be applied to Asian patients with different ischemic stroke subtypes remains unclear. Methods: Patients from 14 South Korean centers were analyzed separately. Patients with ischemic stroke or transient ischemic attack with evidence of atherosclerosis were randomized into LT and HT groups. The primary endpoint was a composite of ischemic stroke, myocardial infarction, coronary or cerebral revascularization, and cardiovascular death. Results: Among 712 enrolled patients, the mean LDL-C level was 71.0 mg/dL in 357 LT patients and 86.1 mg/dL in 355 HT patients. The primary endpoint occurred in 24 (6.7%) of LT and in 31 (8.7%) of HT group patients (adjusted hazard ratio [HR]=0.78; 95% confidence interval [CI]=0.45–1.33, P=0.353). Cardiovascular events alone occurred significantly less frequently in the LT than in the HT group (HR 0.26, 95% CI 0.09–0.80, P=0.019), whereas there were no significant differences in ischemic stroke events (HR 1.12, 95% CI 0.60–2.10, P=0.712). The benefit of LT was less apparent in patients with small vessel disease and intracranial atherosclerosis than in those with extracranial atherosclerosis. Conclusion In contrast to the French TST, the outcomes in Korean patients were neutral. Although LT was more effective in preventing cardiovascular diseases, it was not so in stroke prevention, probably attributed to the differences in stroke subtypes. Further studies are needed to elucidate the efficacy of statins and appropriate LDL-C targets in Asian patients with stroke.

Background and Objectives: Metoclopramide is an antagonist of dopamine D2 receptor and is capable of alleviating chemotherapy-induced nausea and vomiting. However, its underlying mechanisms and function in improving the efficiency of chemotherapy are not fully understood. In this study, we investigated the sensitizing effect of metoclopramide on the platinum-based drugs-mediated apoptosis in human head and neck cancer cells.Subjects and Method Apoptosis was analyzed using a cell-based cytometer. The protein expression and messenger ribonucleic acid (mRNA) levels were assessed by Western blotting and real-time polymerase chain reaction, respectively. Results: Metoclopramide sensitized the platinum-based drug (cisplatin and oxaliplatin)-mediated apoptosis in AMC-HN4 cells, but not in normal cells. Mechanistically, we found that metoclopramide decreased Mcl-1 protein expression through post-translational regulation. Moreover, the overexpression of Mcl-1 prevented apoptosis by combined treatment of metoclopramide and platinum-based drugs. Conclusion Metoclopramide induced proteasome-mediated Mcl-1 downregulation, resulting in increased sensitivity to platinum-based drugs.

Background/Aims: Psoriasis is a common inflammatory skin disorder following non-specific triggers. Involvement of immune system is widely accepted for pathogenesis studies have demonstrated importance of gut microbiota in pathogenesis of inflammatory skin diseases. Proton pump inhibitor (PPI) and histamine-2 receptor antagonist (H2RA) are acid-suppressive drugs widely used for acid related gastrointestinal diseases, and prolonged use has been associated with altered gut microbiota. This study aimed to investigate association between psoriasis and acid suppressing drugs in Korean population. Methods: This study was conducted with 3,662 patients diagnosed with psoriasis between 2002 and 2013 in NHIS-NSC. A total of 14,648 controls were matched at 1:4 based on sex, age, and gastrointestinal disease. ORs were estimated to determine the association between acid suppressing drug use and psoriasis. Results: Our study found a statistically significant association between the prolonged use of acid-suppressive drugs and the development of psoriasis in the Korean population. Specifically, patients with gastrointestinal diseases who used histamine-2 receptor antagonists (H2RA) or proton pump inhibitors (PPI) for extended periods exhibited a higher risk of developing psoriasis. The adjusted odds ratio for psoriasis was 1.89 (95% CI, 1.66–2.17) with long-term use, indicating a clear dose-response relationship. Conclusions Results from our study indicate that prolonged use of H2RA or PPI is associated with the risk of psoriasis among patients with gastrointestinal diseases in Korean population. The risk was increased in dose-response trend after adjusting for confounding variables. Clinicians should be aware of risks associated with prolonged use of acid suppressing drugs.

Background/Aims: Adiponectin, a hormone primarily produced by adipocytes, typically shows an inverse relationship with body mass index (BMI). However, some studies have reported a positive correlation between the two. Thus, this study aimed to examine the relationship between adiponectin level and BMI in diabetic patients, focusing on the impact of past obesity on current adiponectin levels. Methods: We conducted an observational study analyzing data from 323 diabetic patients at Kyungpook National University Hospital. Based on past and current BMIs, participants were categorized into never-obese (nn, n = 106), previously obese (on, n = 43), and persistently obese (oo, n = 73) groups based on a BMI threshold of 25 kg/m2. Adiponectin level and BMI were key variables. Kaplan–Meier analysis assessed their impact on all-cause mortality up to August 2023, with survival differences based on adiponectin quartiles and follow-up starting from patient enrollment (2010–2015). Results: The analysis revealed a significant inverse correlation between adiponectin level and past maximum BMI. The on group exhibited approximately 10% lower adiponectin levels compared to the nn group. This association remained significant after adjusting for current BMI, age, and sex, highlighting the lasting influence of previous obesity on adiponectin levels. Furthermore, survival analysis indicated that patients in the lowest adiponectin quartile had reduced survival, with a statistically significant trend (p = 0.062). Conclusions Findings of this study suggest that lower adiponectin levels, potentially reflecting past obesity, are associated with decreased survival in diabetic patients, underscoring a critical role of adiponectin in long-term health outcomes.

Background/Aims: Krebs von den Lungen-6 (KL-6) is associated with prognosis in patients with COVID-19. However, there is limited data on the correlation between the prognosis of COVID-19 and varying KL-6 levels at different time points. We investigated the optimal cutoff values of the initial and peak serum KL-6 levels to predict mortality and evaluated their correlation with mortality. Methods: This retrospective cohort study collected data on serially collected serum KL-6 levels in patients hospitalized with COVID-19 between October 2020 and January 2022 at a single tertiary hospital in South Korea. The area under the receiver operating characteristic curve and Youden index were used to determine the cutoff points for the initial and peak KL-6 levels that best predicted 30-day mortality. The association between the initial and peak KL-6 values was assessed by univariate and multivariate logistic regression models. Results: A total of 349 patients were included in this study. The mean initial and peak KL-6 levels were significantly higher in the non-survivor group than in the survivor group. The initial and peak KL-6 values that best predicted 30-day mortality were 491.85 U/mL and 660.05 U/mL, respectively. An initial KL-6 level greater than 491.85 U/mL and a peak KL-6 level greater than 660.05 U/mL were significantly associated with 30-day mortality. Conclusions The initial and peak levels of KL-6 were significantly associated with 30-day mortality in hospitalized patients with COVID-19. These findings suggest that serially monitoring blood KL-6 levels could be a valuable prognostic indicator for COVID-19.