Detection of Hepatic Metastasis from Early Delayed Images of Modified Dual-Time-Point F-18 FDG PET/CT Images in a Patient with Breast Cancer.

We present a rare case of focal F-18-2-fluoro-2-deoxyglucose (FDG) uptake in the liver observed during a modified dual-time-point F-18 FDG positron emission tomography (PET)/computed tomography (CT), so-called early delayed scanning, in a 53-year-old woman diagnosed with breast cancer. This metastatic lesion was revealed in 80 min delayed images after FDG injection, but not in the usual one-hour images after injection. Modified dual-time-point F-18 FDG PET/CT is convenient because compared to the 2 h delayed images of dual-time-point PET/CT, it has a shorter scanning time and avoids additional radiation exposure.

Risk Factors for Disease Progression in Glaucoma Patients with Disc Hemorrhage.

PRCIS: Glaucoma eyes with recurrent disc hemorrhage were associated with increased systolic blood pressure and diastolic blood pressure, and increased visit-to-visit diastolic blood pressure variability was associated with glaucoma progression. PURPOSE: In this study, we investigated the effects of the clinical characteristics of disc hemorrhage (DH) and hemodynamic factors on glaucoma progression. METHODS: This retrospective cohort study included 81 eyes with open angle glaucoma and non-recurrent or recurrent DH. Recurrent DH was further classified according to the DH location. Visual field (VF) progression was determined using event-based analysis and Guided Progression Analysis software. The coefficient of variation (CV) of systolic and diastolic blood pressure (SBP and DBP, respectively) was used to measure visit-to-visit variability. Kaplan-Meier survival analysis was used to compare the cumulative risk ratio of progression between groups. RESULTS: The recurrent DH group had significantly higher SBP and DBP (P=0.014 and=0.021, respectively) and a higher proportion of VF progression (P=0.019) than the non-recurrent DH group. In particular, females with recurrent DH had the highest cumulative probability of VF progression (P=0.047, log-rank test). Recurrent DH in a different quadrant was associated with the highest cumulative probability of VF progression than non-recurrent DH (P=0.038, log-rank test). In Cox regression analysis, higher visit-to-visit DBP variability, female sex, and recurrent DH in a different quadrant were significantly associated with glaucoma progression. CONCLUSION: In glaucomatous eyes with DH, increased visit-to-visit DBP variability was associated with glaucoma progression. Our results suggest that hemodynamic factors are involved in the recurrence of DH and progression of glaucoma.

Home-based up-dosing of wheat oral immunotherapy: Real-world effectiveness and predictive factor analysis.

BACKGROUND: Wheat allergy is one of the most prevalent allergens in Korea, decreasing quality of life and causing nutritional repercussions. OBJECTIVE: We aimed to investigate the efficacy and safety of the home-based wheat oral immunotherapy (OIT) using wheat noodles in children with a wheat allergy. METHODS: We conducted a retrospective study involving 72 children aged 3 to 17 years diagnosed with a wheat allergy. Patients received wheat OIT using wheat noodles (n = 50) and were compared with a historical control group (n = 22). Baseline characteristics, adverse events, and immunological changes were assessed. Predictors of successful desensitization were identified using logistic regression analysis. RESULTS: Among 50 patients completing the up-dosing phase, 82.0% achieved desensitization to 2,400 mg of wheat protein, compared to 4.5% in the control group (p < 0.001). During the up-dosing period, the median number of adverse reactions per person was 2, and anaphylaxis occurred in 30.0% (15/50). However, there were no life-threatening adverse events. In multivariable analysis, the presence of asthma (adjusted odds ratio [aOR], 8.88; 95% confidence interval [CI], 1.10-71.97; p = 0.041) and a higher ratio of specific IgE (sIgE) to ω-5-gliadin and total IgE (aOR 19.09, 95%CI 1.21-300.80, p = 0.036) were significantly associated with treatment outcomes of wheat OIT. CONCLUSION: Our study showed the safety and efficacy of home-based wheat OIT using boiled noodles in Korean children with wheat allergies. Careful consideration is warranted for patients with elevated baseline sIgE to ω-5-gliadin to total IgE ratio and a history of asthma.

Genotype Analysis of Respiratory Syncytial Virus Before and After the COVID-19 Pandemic Using Whole-Genome Sequencing: A Prospective, Single-Center Study in Korea From 2019 to 2022.

BACKGROUND: Respiratory syncytial virus (RSV), a highly transmissible virus, is the leading cause of lower respiratory tract infections. We examined molecular changes in the RSV genome before and after the coronavirus disease 2019 (COVID-19) pandemic in Korea, and investigated whether drug-resistant mutations were present. METHODS: In this prospective, single-center study, RSV-positive respiratory samples were collected between September 2019 and December 2022. Long-read whole-genome sequencing (WGS) was performed, and the presence of known drug-resistant substitutions for palivizumab, nirsevimab, and suptavumab was investigated. RESULTS: Overall, 288 respiratory samples were collected from 276 children. WGS data were available for 133 samples (71 and 62 samples from the pre- and post-pandemic periods, respectively). All RSV-A strains (n = 56) belonged to the GA2.3.5 (ON1) genotype, whereas all RSV-B strains (n = 77) belonged to the GB5.0.5a (BA) genotype. No significant differences in genotypes were observed between the pre- and post-pandemic periods. In addition, no notable mutations related to nirsevimab or palivizumab resistance were detected in the F gene. However, the L172Q and S173L substitutions, which are known to confer resistance to suptavumab, were present in all RSV-B samples. CONCLUSION: Despite the unprecedented interruption of RSV seasonality, there were no significant molecular changes in circulating RSV strains in Korea related to nirsevimab or palivizumab resistance before and after the COVID-19 pandemic. However, RSV-specific drug-resistance substitutions for suptavumab were identified.

Prevalence of Severe Atopic Dermatitis and Comorbid Chronic Systemic Diseases Is Increasing in Korean Children and Adolescents.

Severe atopic dermatitis (AD) is not a localized cutaneous disease, but a systemic disease that often accompanies comorbidities. In this nationwide population-based study, we aimed to analyze the prevalence of severe AD and chronic systemic diseases in Koreans aged ≤ 20 years between 2011 and 2019 using the data from the Korean Health Insurance Review and Assessment Service. Total AD and severe AD were defined according to the International Classification of Diseases-10 code L20. In children aged 6-20 years, the prevalence of severe AD significantly increased from 0.02% in 2011 to 0.04% in 2019 (P for trend < 0.001), with the ratio of severe AD to total AD increasing from 0.76% in 2011 to 1.10% in 2019 (P for trend < 0.001). The prevalence rates of severe AD significantly increased between 2011 and 2019 in children aged 6-12 years (P for trend < 0.05) and 13-18 years (P for trend < 0.001). Severe AD was more frequently found in males than in females each year (all P < 0.001, from 2011 to 2019). During the period from 2011 to 2019, the prevalence rate of chronic systemic diseases was higher in subjects with severe AD than in those without AD (P < 0.001) or with mild-to-moderate AD (P < 0.001). In conclusion, our results suggest that the prevalence of severe AD is increasing in Korean children and adolescents and is higher in males and older age groups. Moreover, severe AD is associated with chronic systemic diseases. Therefore, more attention should be paid to managing severe AD.

Survival benefit of inhaled corticosteroids in patients with chronic obstructive pulmonary disease: a nationwide cohort study.

The role of inhaled corticosteroids (ICS) in chronic obstructive pulmonary disease (COPD) is debated. We investigated whether the administration of ICS could lower the mortality risk in patients with COPD. We utilized the Korean National Health Insurance Service-National Sample Cohort database from 2002 to 2019. We included patients who had claim codes for COPD and inhalation respiratory medicine at least twice a year. A time-dependent Cox regression model was employed to estimate the association between ICS usage and survival. The cumulative dose of ICS was classified into three groups, and the mortality risk was compared among these groups. Of 16,463 included patients, there were 4395 (26.7%) deaths during the mean follow-up period of 5.0 years. The time-dependent Cox regression model demonstrated that ICS users had a significantly lower mortality risk compared to non-users (adjusted hazard ratio, 0.89; 95% CI, 0.83-0.94; p < 0.001), particularly among individuals aged ≥ 55 years, women, never smokers, and those with history of asthma or coronary heart disease. Higher cumulative dose groups were associated with a lower mortality risk compared to the lowest cumulative dose group. In conclusion, the administration of ICS seemed to be associated with a lower mortality risk in patients with COPD.

Allosteric modulation of serotonin and dopamine transporters: New insights from computations and experiments.

Human monoamine transporters (MATs) are critical to regulating monoaminergic neurotransmission by translocating their substrates from the synaptic space back into the presynaptic neurons. As such, their primary substrate binding site S1 has been targeted by a wide range of compounds for treating neuropsychiatric and neurodegenerative disorders including depression, ADHD, neuropathic pain, and anxiety disorders. We present here a comparative study of the structural dynamics and ligand-binding properties of two MATs, dopamine transporter (DAT) and serotonin transporter (SERT), with focus on the allosteric modulation of their transport function by drugs or substrates that consistently bind a secondary site S2, proposed to serve as an allosteric site. Our systematic analysis of the conformational space and dynamics of a dataset of 50 structures resolved for DAT and SERT in the presence of one or more ligands/drugs reveals the specific residues playing a consistent role in coordinating the small molecules bound to subsites S2-I and S2-II within S2, such as R476 and Y481 in dDAT and E494, P561, and F556 in hSERT. Further analysis reveals how DAT and SERT differ in their two principal modes of structural changes, PC1 and PC2. Notably, PC1 underlies the transition between outward- and inward-facing states of the transporters as well as their gating; whereas PC2 supports the rearrangements of TM helices near the S2 site. Finally, the examination of cross-correlations between structural elements lining the respective sites S1 and S2 point to the crucial role of coupled motions between TM6a and TM10. In particular, we note the involvement of hSERT residues F335 and G338, and E493-E494-T497 belonging to these two respective helices, in establishing the allosteric communication between S1 and S2. These results help understand the molecular basis of the action of drugs that bind to the S2 site of DAT or SERT. They also provide a basis for designing allosteric modulators that may provide better control of specific interactions and cellular pathways, rather than indiscriminately inhibiting the transporter by targeting its orthosteric site.

Novel Hemodynamic, Vascular Lesion and Cytokine/Chemokine Differences Regarding Sex in a PAH Model.

Sex differences are recognized in pulmonary hypertension, however the progression of disease with regards to vascular lesion formation and circulating cytokines/chemokines is unknown. To determine whether vascular lesion formation, changes in hemodynamics and alterations in circulating chemokines/cytokines differ between male and female. We used a progressive model of PAH, SU/Hx and analyzed cohorts of male and female rats at timepoints suggested to indicate worsening disease. Our analysis included echocardiograpy for hemodynamics, morphometry, immunofluoresecence and chemokine/cytokine analysis of plasma at each time point in both sexes. We found that male rats had significantly increased Fulton index compared to females at each time point as well as increased medial artery thickening at 8-weeks PAH. Further, females exhibit fewer obliterative vascular lesions than males at our latest time point. Our data also show increased IL-4, GM-CSF, IL-10, and MIP-1 that are not observed in females, while females have increased RANTES and CXCL-10 not found in males. Males also have increased infiltrating macrophages in vascular lesions as compared to females. We found that development of progressive PAH in hemodynamics, morphology and chemokine/cytokine circulation differ significantly between males and females. These data suggest a macrophage driven pathology in males, while there may be T-cell protection from vascular damage in female PAH.

Neuronal Cell Differentiation of iPSCs for the Clinical Treatment of Neurological Diseases.

Current chemical treatments for cerebrovascular disease and neurological disorders have limited efficacy in tissue repair and functional restoration. Induced pluripotent stem cells (iPSCs) present a promising avenue in regenerative medicine for addressing neurological conditions. iPSCs, which are capable of reprogramming adult cells to regain pluripotency, offer the potential for patient-specific, personalized therapies. The modulation of molecular mechanisms through specific growth factor inhibition and signaling pathways can direct iPSCs' differentiation into neural stem cells (NSCs). These include employing bone morphogenetic protein-4 (BMP-4), transforming growth factor-beta (TGFß), and Sma-and Mad-related protein (SMAD) signaling. iPSC-derived NSCs can subsequently differentiate into various neuron types, each performing distinct functions. Cell transplantation underscores the potential of iPSC-derived NSCs to treat neurodegenerative diseases such as Parkinson's disease and points to future research directions for optimizing differentiation protocols and enhancing clinical applications.

Two-year carcinogenicity study of a novel plasticizer, bis(2-ethylhexyl) cyclohexane-1,4-dicarboxylate (Eco-DEHCH), by oral diet in Han Wistar rats.

Plasticizers are necessary for the usability of various products, including food contact materials. Exposure to plasticizers is most commonly made through the oral route. Several plasticizers have been reported to have adverse effects on humans and the environment. Thus, the present study aimed to determine the long-term toxicity and carcinogenicity of a novel plasticizer called bis(2-ethylhexyl) cyclohexane-1,4-dicarboxylate (Eco-DEHCH), which is an ecofriendly and biologically less harmful replacer. Groups of 50 male and 50 female Han Wistar rats were fed Eco-DEHCH at daily doses of 1,600, 5,000, or 16,000 ppm in their diet for at least 104 weeks. The rats were regularly monitored for mortality, clinical signs, body weight, food consumption, food efficiency, and perceivable mass. All animals were subjected to complete necropsy and histopathological examination. The results indicate that the rats well tolerated chronic exposure to Eco-DEHCH at highest daily doses of 16,000 ppm, with was equivalent to 805.1 mg/kg/day in males and 1060.6 mg/kg/day in females and did not show signs of toxicity or carcinogenicity. In conclusion, Eco-DEHCH could be a safe and promising alternative plasticizer.

Fermentative aminopyrrolnitrin production by metabolically engineered Corynebacterium glutamicum.

Aminopyrrolnitrin (APRN), a natural halogenated phenylpyrrole derivative (HPD), has strong antifungal and antiparasitic activities. Additionally, it showed 2.8-fold increased photostability compared to pyrrolnitrin, a commercially available HPD with antimicrobial activity. For microbial production of APRN, we first engineered anthranilate phosphoribosyltransferase encoded by trpD from Corynebacterium glutamicum, resulting in a TrpDA162D mutation that exhibits feedback-resistant against L-tryptophan and higher substrate affinity compared to wild-type TrpD. Plasmid-borne expression of trpDA162D in C. glutamicum TP851 strain with two copies of trpDA162D in the genome led to the production of 3.1 g/L L-tryptophan in flask culture. Subsequent step for L-tryptophan chlorination into 7-chloro-L-tryptophan was achieved by introducing diverse sources of genes encoding tryptophan 7-halogenase (PrnA or RebH) and flavin reductase (Fre, PrnF, or RebF). The combined expression of prnA from Serratia grimesii or Serratia plymuthica with flavin reductase gene from Escherichia coli, Pseudomonas fluorescens, or Lechevalieria aerocolonigenes yielded higher production of 7-chloro-L-tryptophan in comparison to other sets of two-component systems. In the next step, production of putative monodechloroaminopyrrolnitrin (MDAP) from 7-chloro-L-tryptophan was achieved through the expression of prnB encoding MDAP synthase from S. plymuthica or P. fluorescens. Finally, an artificial APRN biosynthetic pathway was constructed by simultaneously expressing genes coding for tryptophan 7-halogenase, flavin reductase, MDAP synthase, and MDAP halogenase (PrnC) from different microbial sources within the L-tryptophan-producing TP851 strain. As prnC from S. grimesii or S. plymuthica was introduced into the host strain, which carried plasmids expressing prnA from S. plymuthica, fre from E. coli, and prnB from S. plymuthica, APN3639 and APN3638 accumulated 29.5 mg/L and 28.1 mg/L of APRN in the culture broth. This study represents the first report on the fermentative APRN production by metabolically engineered C. glutamicum.

Automatic assessment of bowel preparation by an artificial intelligence model and its clinical applicability.

BACKGROUND AND AIM: Reliable bowel preparation assessment is important in colonoscopy. However, current scoring systems are limited by laborious and time-consuming tasks and interobserver variability. We aimed to develop an artificial intelligence (AI) model to assess bowel cleanliness and evaluate its clinical applicability. METHODS: A still image-driven AI model to assess the Boston Bowel Preparation Scale (BBPS) was developed and validated using 2361 colonoscopy images. For evaluating real-world applicability, the model was validated using 113 10-s colonoscopy video clips and 30 full colonoscopy videos to identify "adequate (BBPS 2-3)" or "inadequate (BBPS 0-1)" preparation. The model was tested with an external dataset of 29 colonoscopy videos. The clinical applicability of the model was evaluated using 225 consecutive colonoscopies. Inter-rater variability was analyzed between the AI model and endoscopists. RESULTS: The AI model achieved an accuracy of 94.0% and an area under the receiver operating characteristic curve of 0.939 with the still images. Model testing with an external dataset showed an accuracy of 95.3%, an area under the receiver operating characteristic curve of 0.976, and a sensitivity of 100% for the detection of inadequate preparations. The clinical applicability study showed an overall agreement rate of 85.3% between endoscopists and the AI model, with Fleiss' kappa of 0.686. The agreement rate was lower for the right colon compared with the transverse and left colon, with Fleiss' kappa of 0.563, 0.575, and 0.789, respectively. CONCLUSIONS: The AI model demonstrated accurate bowel preparation assessment and substantial agreement with endoscopists. Further refinement of the AI model is warranted for effective monitoring of qualified colonoscopy in large-scale screening programs.

A survey of current practices in post-polypectomy surveillance in Korea.

BACKGROUND/AIMS: We investigated the clinical practice patterns of post-polypectomy colonoscopic surveillance among Korean endoscopists. METHODS: In a web-based survey conducted between September and November 2021, participants were asked about their preferred surveillance intervals and the patient age at which surveillance was discontinued. Adherence to the recent guidelines of the U.S. Multi-Society Task Force on Colorectal Cancer (USMSTF) was also analyzed. RESULTS: In total, 196 endoscopists completed the survey. The most preferred first surveillance intervals were: a 5-year interval after the removal of 1-2 tubular adenomas < 10 mm; a 3-year interval after the removal of 3-10 tubular adenomas < 10 mm, adenomas ≥ 10 mm, tubulovillous or villous adenomas, ≤ 20 hyperplastic polyps < 10 mm, 1-4 sessile serrated lesions (SSLs) < 10 mm, hyperplastic polyps or SSLs ≥ 10 mm, and traditional serrated adenomas; and a 1-year interval after the removal of adenomas with highgrade dysplasia, >10 adenomas, 5-10 SSLs, and SSLs with dysplasia. In piecemeal resections of large polyps ( > 20 mm), surveillance colonoscopy was mostly preferred after 1 year for adenomas and 6 months for SSLs. The mean USMSTF guideline adherence rate was 30.7%. The largest proportion of respondents (40.8%-55.1%) discontinued the surveillance at the patient age of 80-84 years. CONCLUSIONS: A significant discrepancy was observed between the preferred post-polypectomy surveillance intervals and recent international guidelines. Individualized measures are required to increase adherence to the guidelines.

Dietary sugar kelp (Saccharina latissima) consumption did not attenuate atherosclerosis in low-density lipoprotein receptor knockout mice.

We previously demonstrated the beneficial effects of U.S.-grown sugar kelp (Saccharina latissima), a brown seaweed, on reducing serum triglycerides (TG) and total cholesterol (TC) and protecting against inflammation and fibrosis in the adipose tissue of diet-induced obesity mice. In this current study, we aimed to explore whether the dietary consumption of sugar kelp can prevent atherosclerosis using low-density lipoprotein receptor knockout (Ldlr KO) mice fed an atherogenic diet. Eight-week-old male Ldlr KO mice were fed either an atherogenic high-fat/high-cholesterol control (HF/HC) diet or a HF/HC diet supplemented with 6% (w/w) sugar kelp (HF/HC-SK) for 16 weeks. Consumption of sugar kelp significantly increased the body weight gain without altering fat mass and lean mass. Also, there were no significant differences in energy expenditure and physical activities between the groups. The two groups did not show significant differences in serum and hepatic TG and TC levels or the hepatic expression of genes involved in cholesterol and lipid metabolism. Although serum alanine aminotransferase (ALT) activity did not differ significantly between the two groups, there were significant increases in the expression of macrophage markers, including adhesion G protein-coupled receptor E1 and cluster of differentiation 68, as well as tumor necrosis factor alpha in the HF/HC-SK group compared to the HF/HC mice. The consumption of sugar kelp did not elicit a significant effect on the development of aortic lesions. Moreover, lipopolysaccharide-stimulated splenocytes isolated from HF/HC-SK-fed mice showed no significant changes in the mRNA levels of pro-inflammatory genes compared with those from the HF/HC mice. In summary, the consumption of dietary sugar kelp did not elicit anti-atherogenic and hepatoprotective effects in Ldlr KO mice.

Transcriptome profiling and characterization of peritoneal metastasis ovarian cancer xenografts in humanized mice.

Although immunotherapy has not yet been as successful in ovarian cancer (OC), it remains a potential therapeutic strategy. Preclinical models of OC are necessary to evaluate the efficacy of immuno-oncology (IO) drugs targeting human immune components but have been underutilized. Developing mouse models with a humanized (Hu) immune system can help understand the human immune response to IO drugs which have demonstrated limited effectiveness in OC patients. We established OC xenograft Hu-mouse models by intraperitoneally injecting luciferase-expressing SKOV-3 Luc and OVCAR-3 Luc OC cells into CD34+ Hu-mice. Tumor growth was monitored through bioluminescence imaging (BLI). In the SKOV-3 Luc Hu-mouse model, we assessed the efficacy of PD-1 blockade with pembrolizumab. We observed the presence of human lymphocyte and myeloid cell subsets within the tumors, lymph nodes, blood, and spleens in these models. Notably, these tumors exhibited a high prevalence of tumor-infiltrating macrophages. Furthermore, we identified HDAC class I target genes, and genes associated with epithelial-mesenchymal transition (EMT) and fibroblasts in the tumors of Hu-mice treated with pembrolizumab. Our xenograft Hu-mouse model of OC provides a valuable tool for investigating the efficacy of IO drugs. The insights gained from this model offer useful information to explore potential mechanisms associated with unresponsive anti-PD-1 treatment in OC.

Genome-wide association studies in a large Korean cohort identify novel quantitative trait loci for 36 traits and illuminates their genetic architectures.

Genome-wide association studies (GWAS) have been predominantly conducted in populations of European ancestry, limiting opportunities for biological discovery in diverse populations. We report GWAS findings from 153,950 individuals across 36 quantitative traits in the Korean Cancer Prevention Study-II (KCPS2) Biobank. We discovered 616 novel genetic loci in KCPS2, including an association between thyroid-stimulating hormone and CD36. Meta-analysis with the Korean Genome and Epidemiology Study, Biobank Japan, Taiwan Biobank, and UK Biobank identified 3,524 loci that were not significant in any contributing GWAS. We describe differences in genetic architectures across these East Asian and European samples. We also highlight East Asian specific associations, including a known pleiotropic missense variant in ALDH2, which fine-mapping identified as a likely causal variant for a diverse set of traits. Our findings provide insights into the genetic architecture of complex traits in East Asian populations and highlight how broadening the population diversity of GWAS samples can aid discovery.