Comparative Analysis of Seven Equations for Estimated Glomerular Filtration Rate and Their Impact on Chronic Kidney Disease Categorization in Korean Patients at Local Clinics and Hospitals.

(1) Background: Accurate estimation of the glomerular filtration rate (eGFR) is essential for the early detection of chronic kidney disease (CKD), targeted interventions, and ongoing monitoring. Although various equations for calculating eGFR exist, comparative studies on eGFR levels and the impact of these equations on CKD prevalence are limited in the Korean population. (2) Methods: We compared eGFR levels calculated using seven equations and investigated the prevalence of CKD through a retrospective analysis of the data from Korean adult patients who visited local clinics and hospitals and underwent simultaneous serum creatinine (Cr) and cystatin C (Cys-C) measurements. The equations analyzed were: 2006 MDRD, 2009 CKD-EPI Cr, 2012 CKD-EPI Cys-C, 2012 CKD-EPI Cr & Cys-C, 2021 CKD-EPI Cr, 2021 CKD-EPI Cr & Cys-C, and 2021 EKFC. (3) Results: This study included 6688 Korean patients (3736 men and 2952 women; median age: 61.4; IQR: 47.2-73.4). Among the equations, the median eGFR levels were the highest when using the 2021 CKD-EPI Cr & Cys-C equation (85.1 mL/min/1.73 m2) and the lowest when using the 2006 MDRD equation (73.4 mL/min/1.73 m2). The highest prevalence of decreased eGFR < 60 mL/min/1.73 m2 (equivalent to or worse than G3a CKD) was noted with the 2012 CKD-EPI Cys-C equation (32.4%), while the lowest was with the 2021 CKD-EPI Cr equation (22.9%), resulting in a maximum prevalence difference of 9.5%. (4) Conclusions: The prevalence of CKD varies based on the eGFR equation used and the patient's age. Equations that include Cys-C may identify a larger number of patients with decreased kidney function.

AI Improves Nodule Detection on Chest Radiographs in a Health Screening Population: A Randomized Controlled Trial.

Background The impact of artificial intelligence (AI)-based computer-aided detection (CAD) software has not been prospectively explored in real-world populations. Purpose To investigate whether commercial AI-based CAD software could improve the detection rate of actionable lung nodules on chest radiographs in participants undergoing health checkups. Materials and Methods In this single-center, pragmatic, open-label randomized controlled trial, participants who underwent chest radiography between July 2020 and December 2021 in a health screening center were enrolled and randomized into intervention (AI group) and control (non-AI group) arms. One of three designated radiologists with 13-36 years of experience interpreted each radiograph, referring to the AI-based CAD results for the AI group. The primary outcome was the detection rate, that is, the number of true-positive radiographs divided by the total number of radiographs, of actionable lung nodules confirmed on CT scans obtained within 3 months. Actionable nodules were defined as solid nodules larger than 8 mm or subsolid nodules with a solid portion larger than 6 mm (Lung Imaging Reporting and Data System, or Lung-RADS, category 4). Secondary outcomes included the positive-report rate, sensitivity, false-referral rate, and malignant lung nodule detection rate. Clinical outcomes were compared between the two groups using univariable logistic regression analyses. Results A total of 10 476 participants (median age, 59 years [IQR, 50-66 years]; 5121 men) were randomized to an AI group (n = 5238) or non-AI group (n = 5238). The trial met the predefined primary outcome, demonstrating an improved detection rate of actionable nodules in the AI group compared with the non-AI group (0.59% [31 of 5238 participants] vs 0.25% [13 of 5238 participants], respectively; odds ratio, 2.4; 95% CI: 1.3, 4.7; P = .008). The detection rate for malignant lung nodules was higher in the AI group compared with the non-AI group (0.15% [eight of 5238 participants] vs 0.0% [0 of 5238 participants], respectively; P = .008). The AI and non-AI groups showed similar false-referral rates (45.9% [56 of 122 participants] vs 56.0% [56 of 100 participants], respectively; P = .14) and positive-report rates (2.3% [122 of 5238 participants] vs 1.9% [100 of 5238 participants]; P = .14). Conclusion In health checkup participants, artificial intelligence-based software improved the detection of actionable lung nodules on chest radiographs. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Auffermann in this isssue.

Prevalence of Iron Deficiency Anemia Indicated for Intravenous Iron Treatment in the Korean Population.

We aimed to investigate the number and prevalence of patients indicated for intravenous iron treatment in a large Korean population using criteria based on laboratory test results in an effort to extract indirect information on the need for intravenous iron treatment. Between 1 January 2019 and 31 December 2021, a total of 83,994 Korean patients (30,499 men and 53,495 women) with a median age of 46 years (interquartile range, 30-61) were evaluated using iron deficiency anemia-associated laboratory tests and serum creatinine tests of estimated glomerular filtration rates. The overall prevalence of anemia (Hb ≤ 11 g/dL) was 16.5%, and the proportion of patients with possible chronic kidney disease who had an estimated glomerular filtration rate < 60 mL/min/1.73 m2 was 11.4%. The number of patients indicated for reimbursable intravenous iron treatment was higher in women than in men, higher in older patients, and higher in 2021 than in 2019 (all p < 0.001). The prevalence of patients indicated for reimbursable intravenous iron treatment was up to 30.0% in those ≥ 80 years of age in 2019. The results of this study provide basic knowledge about the use of iron deficiency anemia-associated laboratory tests in planning nutritional support programs using an intravenous iron formulation in Korea.

Upconverting nanoparticle-containing erythrocyte-sized hemoglobin microgels that generate heat, oxygen and reactive oxygen species for suppressing hypoxic tumors.

Inspired by erythrocytes that contain oxygen-carrying hemoglobin (Hb) and that exhibit photo-driven activity, we introduce homogenous-sized erythrocyte-like Hb microgel (µGel) systems (5-6 µm) that can (i) emit heat, (ii) supply oxygen, and (iii) generate reactive oxygen species (ROS; 1O2) in response to near-infrared (NIR) laser irradiation. Hb µGels consist of Hb, bovine serum albumin (BSA), chlorin e6 (Ce6) and erbium@lutetium upconverting nanoparticles (UCNPs; ∼35 nm) that effectively convert 808 nm NIR light to 660 nm visible light. These Hb µGels are capable of releasing oxygen to help generate sufficient reactive oxygen species (1O2) from UCNPs/Ce6 under severely hypoxic condition upon NIR stimulation for efficient photodynamic activity. Moreover, the Hb µGels emit heat and increase surface temperature due to NIR light absorption by heme (iron protoporphyrin IX) and display photothermal activity. By changing the Hb/UCNP/Ce6 ratio and controlling the amount of NIR laser irradiation, it is possible to formulate bespoke Hb µGels with either photothermal or photodynamic activity or both in the context of combined therapeutic effect. These Hb µGels effectively suppress highly hypoxic 4T1 cell spheroid growth and xenograft mice tumors in vivo.

Effects of fun-seeking and external locus of control on smoking behaviour: a cross-sectional analysis on a cohort of working men in Singapore.

OBJECTIVES: We examined the combined effects of behavioural inhibition and behavioural activation, on one hand, and locus of control, on the other hand, on different categories of smoking behaviour (non-smoking, ex-smoking, occasional smoking, daily smoking). DESIGN: This study adopted a cross-sectional design. Participants completed questionnaires regarding demographics, smoking patterns, behavioural inhibition/behavioural activation systems and locus of control. SETTING: The study was conducted across four companies from the transportation, cooling plant and education sectors in Singapore. PARTICIPANTS: Three hundred sixty-nine male working adults were included in the final sample. RESULTS: Corroborating previous research, a logistic regression model examining behavioural inhibition/behavioural activation systems revealed that the fun-seeking aspect of behavioural activation was a unique predictor in distinguishing non-smokers from daily smokers (OR=1.24, p=0.012). By contrast, in a separate model examining locus of control, external locus of control was found to be a unique predictor in distinguishing non-smokers from daily smokers (OR=1.13, p<0.001). In addition, a third model combining both behavioural inhibition/behavioural activation systems and locus of control found that only external locus of control remained a significant predictor (OR=1.12, p<0.001). Further analyses revealed a mediating effect of external locus of control on the relationship between fun-seeking and smoking behaviour. That is, the increase in the odds of daily smoking due to fun-seeking was explained by external locus of control (direct pathway OR=1.20, p=0.058; indirect pathway OR=1.04, p<0.050). CONCLUSIONS: Overall, fun-seeking through its influence on external locus of control indirectly affects daily smoking behaviour, suggesting a more complex relationship than shown in previous research.

Seroprevalence of Anti-Thyroglobulin Antibodies in Korea.

BACKGROUND: The appropriate use of the thyroglobulin (Tg) test involves the concurrent measurement of Tg auto-antibodies (Tg Ab) due to the potential for false low or false high Tg due to Tg Ab interference. METHODS: We retrospectively reviewed Tg and Tg Ab test results requested from local clinics and hospitals in Korea between July 1, 2020 and June 30, 2021. RESULTS: During the study period, 13,811 Tg tests were performed. Among them, 6,769 Tg tests were identified as being repeatedly measured from 2,988 Korean adults. Among the 6,769 performed Tg tests, 2,733 (40.4%) did not have concurrently performed Tg Ab tests. Among the 2,988 subjects, 1,089 (36.4%) had no concurrently measured Tg Ab test results. Among 4,036 Tg results with concurrently measured Tg Ab, 1,045 (25.9%) had positive Tg Ab results, which could interfere with Tg concentration measurements. CONCLUSIONS: The Tg Ab test appears to be underutilized in Korea.

Etomoxir, a carnitine palmitoyltransferase 1 inhibitor, combined with temozolomide reduces stemness and invasiveness in patient-derived glioblastoma tumorspheres.

INTRODUCTION: The importance of fatty acid oxidation (FAO) in the bioenergetics of glioblastoma (GBM) is being realized. Etomoxir (ETO), a carnitine palmitoyltransferase 1 (CPT1) inhibitor exerts cytotoxic effects in GBM, which involve interrupting the FAO pathway. We hypothesized that FAO inhibition could affect the outcomes of current standard temozolomide (TMZ) chemotherapy against GBM. METHODS: The FAO-related gene expression was compared between GBM and the tumor-free cortex. Using four different GBM tumorspheres (TSs), the effects of ETO and/or TMZ was analyzed on cell viability, tricarboxylate (TCA) cycle intermediates and adenosine triphosphate (ATP) production to assess metabolic changes. Alterations in tumor stemness, invasiveness, and associated transcriptional changes were also measured. Mouse orthotopic xenograft model was used to elucidate the combinatory effect of TMZ and ETO. RESULTS: GBM tissues exhibited overexpression of FAO-related genes, especially CPT1A, compared to the tumor-free cortex. The combined use of ETO and TMZ further inhibited TCA cycle and ATP production than single uses. This combination treatment showed superior suppression effects compared to treatment with individual agents on the viability, stemness, and invasiveness of GBM TSs, as well as better downregulation of FAO-related gene expression. The results of in vivo study showed prolonged survival outcomes in the combination treatment group. CONCLUSION: ETO, an FAO inhibitor, causes a lethal energy reduction in the GBM TSs. When used in combination with TMZ, ETO effectively reduces GBM cell stemness and invasiveness and further improves survival. These results suggest a potential novel treatment option for GBM.

Adsorptive removal of micron-sized polystyrene particles using magnetic iron oxide nanoparticles.

Microplastics are able to pass through many filtration systems due to their small sizes, making it difficult to remove them from, for example, water. In this study, we evaluated the ability of using magnetic iron oxide (Fe3O4) nanoparticles to achieve the adsorptive removal of micron-sized polystyrene (microPS) particles. Application of a magnet for 3 min to an aqueous sample of microPS particles mixed with iron oxide nanoparticles for 1 min was able to effectively remove the microPS particles from the water. Transmission electron microscopy images of such samples showed the formation of Fe3O4-PS complexes due to the adsorption of PS particles onto iron oxide nanoparticles. This adsorption followed the pseudo-first order kinetic and Langmuir isotherm model. Hydrophobic interactions were concluded from our experiments to be the main interactions involved in the aggregation of iron oxide with PS particles. Ions present in an environmental freshwater sample inhibited the ability of iron oxide particles to become adsorbed PS particles, but the adsorption performance was improved by increasing the amount of iron oxide particles. The iron oxide particles could be recovered from the Fe3O4-PS complexes by desorption process. Our study showed the potential advantages of iron oxide particles for removing environmental pollutants of microplastics via highly efficient and environmental-friendly procedure.

Reference intervals of anti-Müllerian hormone in Korean women.

BACKGROUND: Limited data are available with reference intervals of serum anti-Müllerian hormone (AMH) level in Korean women. METHODS: We retrospectively reviewed serum AMH test results performed with automated electrochemiluminescence immunoassay in Korean women who visited health promotion centers between January 2019 and December 2020. Serum AMH results by age group were compared with previously reported reference intervals. RESULTS: During the 2-year study period, a total of 1953 AMH test results from Korean women (age 20-49 years) undergoing general health checkups were obtained. Serum AMH level differed significantly by age group. Peak AMH level was observed at age 25-29 years and decreased to undetectable for subjects older than 44 years. The 2.5th, 5th, and 10th percentile values of the present study were comparable with previously assessed lower limits of reference intervals. The upper limit of the reference interval defined as the 97.5th percentile value in women younger than 35 years was higher than that of Western populations. The 90th percentile value of the present study population was similar to the 95th or 97.5th percentile value of reference intervals for Western populations of women younger than 35 years. CONCLUSION: Understanding patient populations and differences in reference intervals by age group and measurement method can help guide clinical decisions and clinical laboratory analysis.

Removable coatings: Thermal stability and decontamination of steel surfaces from 241Am.

This study presents a comparative analysis of several commercial removable materials for radioactive decontamination of steel surfaces using 241Am as representative radionuclide. The selection criteria of removable coatings for this study included a history of application, commercial availability, easy handling conditions and different composition and formulation. Carbon steel and stainless steel coupons were utilized as common industrial materials, and the experimental series were expanded to include the rusting treatment of these surfaces as it is common for decommissioned nuclear facilities. Radionuclide 241Am was deposited on the coupon surfaces and used to evaluate decontamination efficiency of the removable coatings, which were pre-screened for the ease of application and removal from the surface. Selected coatings were characterized with Fourier-transform infrared spectroscopy and thermogravimetric analysis, decontamination efficiencies for different types of steel surfaces, and potential enhancement of the removal efficiencies of the select removable coatings via amendment with EDTA. Across all the coatings, decontamination efficiencies for stainless steel (both pristine and with oxidizing treatment) were higher than for pristine carbon steel, which in turn were higher than for rusted carbon steel. Amendment with EDTA improved removal efficiency of a removable coating. CC Strip coating exhibited easy handling and high decontamination efficiency, (up to 97% when EDTA-amended), but its drying time was the longest, and thermal analysis indicated higher release of energy during thermal decomposition compared to the other coatings. Hydrogel-based DeconGel coating, even though not the easiest in handling among the rest of materials, exhibited high decontamination efficiency, efficient drying at the ambient temperature leading to the loss of about 80 wt% due to solvent evaporation, and extremely low heat released during thermal decomposition; therefore, it is considered a preferable choice for the considered factors.

Ki67 Index Is the Most Powerful Factor for Predicting the Recurrence in Atypical Meningioma : Retrospective Analysis of 99 Patients in Two Institutes.

OBJECTIVE: The primary objective of this study was to identify predicting factors for local control (LC) of atypical meningioma, and we validated them with comparing the predicting factors for recurrence-free survival (RFS). We also examined the rate of LC after surgical resection with or without adjuvant treatment and RFS. METHODS: Clinical and radiological records of patients with atypical meningiomas diagnosed at two institutes from January 2000 to December 2018 were reviewed retrospectively. Histopathological features were also reviewed using formalin-fixed paraffin embedded samples from pathological archives. RESULTS: Of the 99 atypical meningiomas eligible for analysis, 36 (36.4%) recurred during the follow-up period (mean, 83.3 months; range, 12-232 months). The rate of 3-year LC and 5-year LC was 80.8% and 74.7%, respectively. The mean time-to-recurrence was 49.4 months (range, 12-150). The mean RFS was 149.3 months (95% confidence interval, 128.8-169.8 months) during the mean follow-up duration of 83.3 months (range, 12-232 months). Multivariate analysis using Cox proportional-hazard regression model showed that the extent of resection (hazard ratio [HR], 4.761; p=0.013), Ki67 index (HR, 8.541; p=0.004), mitotic index (HR, 3.275; p=0.044), and tumor size (HR, 3.228; p=0.041) were independently associated with LC. These factors were also statistically associated with RFS. In terms of radiotherapy after surgical resection, the recurrence was not prevented by immediate radiotherapy because of the strong effect of proliferative index on recurrence. CONCLUSION: The present study suggests that the extent of resection, proliferative index (according to Ki67 expression) and mitotic index, and tumor size are associated with recurrence of atypical meningiomas. However, our results should be further validated through prospective and randomized clinical trials to overcome the inborn bias of retrospective nature of the study design.

Intraindividual Changes in Mac-2 Binding Protein Glycosylation Isomer (M2BPGi) Performed in Korean Subjects.

BACKGROUND: Limited data are available regarding intraindividual changes in the Mac-2 binding protein glycosylation isomer (M2BPGi), a liver fibrosis biomarker, performed for health checkups in Korean subjects. METHODS: Through a laboratory information system, we retrospectively investigated longitudinally measured M2BPGi to assess intraindividual changes in M2BPGi test results. RESULTS: During a 38-month study period, 526 test results from 246 Korean subjects undergoing general health checkups were requested from 13 local clinics and hospitals. Among all 246 subjects, 190 (77.2%) exhibited negative M2BPGi (< 1.0 C.O.I.) during the initial measurement. Among all 246 subjects, 210 (85.4%) did not experience any changes in qualitative results during a follow-up. Among 42 subjects with initially 1+ positive results for M2BPGi, 17 (40.5%) changed to a negative M2BPGi result at least once during follow-up. No subjects with initially negative results or 1+ positive (1.0 ≤ C.O.I. < 3.0) results changed to 2+ positive (≥ 3.0 C.O.I.) results during the 38-month follow-up period. CONCLUSIONS: Some subjects exhibited qualitative changes in M2BPGi during follow-up health examinations. Future studies are needed to clarify the clinical implication of such changes.

Clinical Anti-aging Efficacy of Propolis Polymeric Nanoparticles Prepared by a Temperature-induced Phase Transition Method.

BACKGROUND: Collagen forms a dermal matrix in the skin. Biosynthesis and decomposition of collagen are the major processes in skin aging. Propolis is rich in flavonoids and phenolic compounds, which are known to be effective in preventing skin aging, including the enhancement of fibroblast proliferation, activation, and growth capacity. OBJECTIVES: The aim of this study was to develop a poorly soluble propolis extract as an active ingredient in cosmetic products for anti-aging efficacy. METHODS & RESULTS: Polymeric nanoparticles containing propolis extract, polyethylene glycol 400, and poloxamer 407 were prepared via a temperature-induced phase transition method. The particle size of the polymeric nanoparticles was approximately 20.75 nm. The results of an in vitro procollagen type I carboxy-terminal peptide assay and a matrix metalloproteinase-1 inhibition assay showed that the polymeric nanoparticles increased collagen production by 19.81%-24.59% compared to blank (p < 0.05), and significantly reduced intracellular collagenase activity by 7.46%-31.52% compared to blank (p < 0.05). In a clinical trial, polymeric nanoparticles in a cosmetic formulation were applied around the eyes of 24 female subjects for 8 weeks. Five skin parameters were significantly improved after the application of the test ampoule. Visual evaluation using the Global Photo Damage Score showed a significant reduction in wrinkles after the application of the test ampoules (p < 0.001). CONCLUSIONS: This study outlines the development of stable polymeric nanoparticles containing poorly soluble propolis in a cosmetic formulation, and its efficacy in wrinkle improvement. The developed polymeric nanoparticles were effective for alleviating wrinkles and can be used for pharmaceutical applications that utilize propolis as antiseptic, anti-inflammatory, antimycotic, antifungal, antibacterial, antiulcer, anticancer, and immunomodulatory agents.

Hypo-trimethylation of Histone H3 Lysine 4 and Hyper-tri/dimethylation of Histone H3 Lysine 27 as Epigenetic Markers of Poor Prognosis in Patients with Primary Central Nervous System Lymphoma.

PURPOSE: This study aimed to investigate the methylation status of major histone modification sites in primary central nervous system lymphoma (PCNSL) samples and examine their prognostic roles in patients with PCNSL. MATERIALS AND METHODS: Between 2007 and 2020, 87 patients were histopathologically diagnosed with PCNSL. We performed immunohistochemical staining of the formalin-fixed paraffin-embedded samples of PCNSL for major histone modification sites, such as H3K4, H3K9, H3K27, H3K14, and H3K36. After detection of meaningful methylation sites, we examined histone modification enzymes that induce methylation or demethylation at each site using immunohistochemical staining. The meaningful immunoreactivity was validated by western blotting using fresh tissue of PCNSL. RESULTS: More frequent recurrences were found in hypomethylation of H3K4me3 (p=0.004) and hypermethylation of H3K27me2 (p<0.001) and H3K27me3 (p=0.002). These factors were also statistically related to short PFS and overall survival in the univariate and multivariate analyses. Next, histone modification enzymes inducing the demethylation of H3K4 (lysine-specific demethylase-1/2 and Jumonji AT-rich interactive domain [JARID] 1A-D]) and methylation of H3K27 (enhancer of zeste homolog [EZH]-1/2) were immu- nohistochemically stained. Among them, the immunoreactivity of JARID1A inversely associated with the methylation status of H3K4me3 (R2=-1.431), and immunoreactivity of EZH2 was directly associated with the methylation status of H3K27me2 (R2=0.667) and H3K27me3 (R2=0.604). These results were validated by western blotting in fresh PCNSL samples. CONCLUSION: Our study suggests that hypomethylation of H3K4me3 and hypermethylation of H3K27me2 and H3K27me3 could be associated with poor outcomes in patients with PCNSL and that these relationships are modified by JARID1A and EZH2.

Neurocognitive and psychological functioning of pediatric brain tumor patients undergoing proton beam therapy for three different tumor types.

BACKGROUND: A high proportion of pediatric patients with brain tumors (BTs) are known to experience a decline in neurocognitive function after treatment. We prospectively examined neuropsychological functioning of patients with BTs of varying tumor types at different time points before, during, and after proton beam therapy. MATERIALS AND METHODS: A total of 98 patients with posterior fossa tumors (PFTs; n = 33), germ cell tumors (GCTs; n = 52), and other supratentorial tumors (STTs; n = 13) underwent baseline neuropsychological assessments and 57 patients underwent follow-up assessments. RESULTS: All groups displayed significantly lower performance intelligence quotient (PIQ) and processing speed (PS) scores than the normative means at baseline. The PFT group exhibited significantly lower scores for full-scale IQ, PIQ, PS, attention, and executive function. The GCT group displayed full-scale IQ scores within the normal range, but a significantly high proportion had memory deficits. In the STT group, all functions except for the PIQ and PS were intact. Longitudinal evaluations demonstrated stable global IQ scores over time in all groups. In the PFT group, verbal comprehension, attention, and PS improved over time. However, in the GCT group, verbal IQ scores declined significantly and psychological problems worsened over time, which were correlated with poorer neurocognitive function at 3-5 years after treatment. In the STT group, no significant changes were observed. CONCLUSION: Because patients with BTs exhibit various types of neurocognitive deficit before radiotherapy, early cognitive treatment tailored to the tumor type maybe beneficial. Interventions for psychological problems and memory function may be necessary, especially for patients with GCT.

Value of a deep learning-based algorithm for detecting Lung-RADS category 4 nodules on chest radiographs in a health checkup population: estimation of the sample size for a randomized controlled trial.

OBJECTIVE: To explore the value of a deep learning-based algorithm in detecting Lung CT Screening Reporting and Data System category 4 nodules on chest radiographs from an asymptomatic health checkup population. METHODS: Data from an annual retrospective cohort of individuals who underwent chest radiographs for health checkup purposes and chest CT scanning within 3 months were collected. Among 3073 individuals, 118 with category 4 nodules on CT were selected. A reader performance test was performed using those 118 radiographs and randomly selected 51 individuals without any nodules. Four radiologists independently evaluated the radiographs without and with the results of the algorithm; and sensitivities/specificities were compared. The sample size needed to confirm the difference in detection rates was calculated, i.e., the number of true-positive radiographs divided by the total number of radiographs. RESULTS: The sensitivity of the radiologists substantially increased aided by the algorithm (38.8% [183/472] to 45.1% [213/472]; p < .001) without significant change in specificity (94.1% [192/204] vs. 92.2% [188/204]; p = .22). Pooled radiologists detected more nodules with the algorithm (32.0% [156/488] vs. 38.9% [190/488]; p < .001), without alteration of false-positive rates (0.09 [62/676], both). Pooled detection rates for the annual cohort were 1.49% (183/12,292) and 1.73% (213/12,292) without and with the algorithm, respectively. A sample size of 41,776 in each arm would be required to demonstrate significant detection rate difference with < 5% type I error and > 80% power. CONCLUSION: Although readers substantially increased sensitivity in detecting nodules on chest radiographs from a health checkup population aided by the algorithm, detection rate difference was only 0.24%, requiring a sample size >80,000 for a randomized controlled trial. KEY POINTS: • Aided by a deep learning algorithm, pooled radiologists improved their sensitivity in detecting Lung-RADS category 4 nodules on chest radiographs from a health checkup population (38.8% [183/472] to 45.1% [213/472]; p < .001), without increasing false-positive rate. • The prevalence of the Lung-RADS category 4 nodules was 3.8% (118/3073) on the population, resulting in only 0.24% increase of the detection rate for the radiologists with assistance of the algorithm. • To confirm the significant detection rate increase by a randomized controlled trial, a sample size of 84,000 would be required.

Conservative Treatment Without Any Intervention Compared With Other Therapeutic Strategies for Symptomatic Patent Ductus Arteriosus in Extremely Preterm Infants: A Nationwide Cohort Study in Korea.

Objective: Although symptomatic treatment is the most preferred treatment strategy for proven symptomatic patent ductus arteriosus (PDA), a considerable number of infants only received conservative treatment without any pharmacological or surgical interventions in the lower gestational age and lower birth weight group in Korea. We compared in-hospital outcomes of infants treated conservatively without any intervention and those of infants managed by other therapeutic strategies in extremely preterm infants with symptomatic PDA. Methods: A prospectively collected cohort study for 2,303 infants with gestational ages <28 weeks from the Korean Neonatal Network database. These infants were classified into four groups according to the presence of PDA-related symptoms and therapeutic treatment strategy: prophylactic treatment group, pre-symptomatic treatment (PST) group, symptomatic treatment (ST) group, and conservative treatment (CT) without any intervention group. Results: In multivariable logistic regression analysis, the risk of death was significantly decreased in the PST group (adjusted odds ratio [aOR] = 0.507; 95% confidence interval [CI] 0.311-0.826) and ST group (aOR = 0.349; 95% CI: 0.230-0.529) compared with the CT group. However, the risk of composite outcome of severe bronchopulmonary dysplasia or death had not increased in the PST group and ST group. Neonatal death due to pulmonary hemorrhage or neurological disease was significantly higher in the CT group than in the PST group or ST group. Conclusion: In extremely preterm infants, who are at highest risk of PDA-related morbidities and mortality, even less interventional approach for PDA can be allowed; the rescued pharmacological or surgical interventions are necessary if they met the criteria for hemodynamically significant PDA.

Simple screening of microplastics in bottled waters and environmental freshwaters using a novel fluorophore.

Screening of polymeric microplastic debris can help to assess the extent to which plastics contaminate the environment. We here developed an easy- and rapid-to-perform method for the screening of plastic polymers, based on a newly employed fluorophore, namely 1-pyrenebutyric acid N-hydroxysuccinimidyl ester (PBN). The PBN fluorophore was capable of staining diverse synthetic microplastic polymers within 5 min, including those displaying various particle sizes and shapes. The fluorescence intensities of the microplastics were considerably enhanced after the short-duration staining. The screening method was shown to be highly effective in the detection of polyethylene (PE), poly(ethylene terephthalate) (PET), polyvinyl chloride (PVC), polyamide-6 (PA-6), polypropylene (PP), polystyrene (PS), polycarbonate (PC), polyvinylidenechloride (PVDC), and polyurethane (PU), with a lowest analyzed particle size of 15 µm. Using our screening method, plastic contamination was investigated in commercially available bottled waters and environmental waters, specifically urban freshwaters. This study demonstrated high affinity levels of the newly proposed PBN fluorophore for a broad range of polymers and its ability to be used to discernibly identify polymer particles.

TREM2 promotes natural killer cell development in CD3-CD122+NK1.1+ pNK cells.

BACKGROUND: Triggering receptor expressed on myeloid cells 2 (TREM2) signaling is considered to regulate anti-inflammatory responses in macrophages, dendritic cell maturation, osteoclast development, induction of obesity, and Alzheimer's disease pathogenesis. However, little is known regarding the effect of TREM2 on natural killer (NK) cells. RESULTS: Here, we demonstrated for the first time that CD3-CD122+NK1.1+ precursor NK (pNK) cells expressed TREM2 and their population increased in TREM2-overexpressing transgenic (TREM2-TG) mice compared with that in female C57BL/6 J wild type (WT) mice. Both NK cell-activating receptors and NK cell-associated genes were expressed at higher levels in various tissues of TREM2-TG mice than in WT mice. In addition, bone marrow-derived hematopoietic stem cells (HSCs) of TREM2-TG mice (TG-HSCs) successfully differentiated into NK cells in vitro, with a higher yield from TG-HSCs than from WT-HSCs. In contrast, TREM2 signaling inhibition by TREM2-Ig or a phosphatidylinositol 3-kinase (PI3K) inhibitor affected the expression of the NK cell receptor repertoire and decreased the expression levels of NK cell-associated genes, resulting in significant impairment of NK cell differentiation. Moreover, in melanoma-bearing WT mice, injection of bone marrow cells from TREM2-TG mice exerted greater antitumor effects than that with cells from WT control mice. CONCLUSIONS: Collectively, our data clearly showed that TREM2 promoted NK cell development and tumor regression, suggesting TREM2 as a new candidate for cancer immunotherapy.

Test Utilization for Thyroglobulin and Anti-Thyroglobulin Antibody Assays in Korea.

BACKGROUND: When measuring thyroglobulin (Tg), simultaneous measurement of Tg autoantibodies (Ab) is recommended by clinical guidelines for follow-up of patients with differentiated thyroid cancers after thyroidectomy and radioactive iodine ablation. We aimed to investigate test utilization of Tg and Tg Ab assays in local clinics and hospitals in Korea. METHODS: We retrospectively reviewed data from the laboratory information system between November 6, 2017 and December 31, 2019. RESULTS: During the study period, 10,551 Tg tests were performed on 2,592 Korean adults from 97 local clinics and hospitals. Among them, 3,924 (37.2%) test results lacked concurrent Tg Ab assays, while 6,627 test results had concurrently measured Tg Ab, and 528 (8.0%) showed positive Tg Ab results, which could interfere with measurement of Tg concentration. CONCLUSIONS: The results of this study provide basic information regarding test utilization of Tg Ab assays to improve test utilization for accurate Tg measurement in Korean patients.