Recent neuropathological and imaging studies support the concept of “brain-first vs. body-first” Parkinson’s disease (PD), which is based on the α-synuclein origin site and connectome model. The body-first phenotype is characterized by early involvement of the peripheral autonomic nervous system, particularly the cardiac sympathetic nerves and enteric nerves. 123I-meta-iodobenzylguanidine (123I-MIBG) myocardial scintigraphy is a well-established method for evaluating cardiac sympathetic innervation. This review explores the potential of 123I-MIBG scintigraphy as a biomarker to differentiate the body-first phenotype from the brain-first phenotype. Reduced 123I-MIBG uptake has been observed in idiopathic rapid eye movement (REM) sleep behavior disorder, pure autonomic failure, and incidental Lewy body disease—conditions strongly associated with prodromal or early-stage PD. Postmortem and biopsy evidence indicates α-synuclein accumulation in cardiac nerves and other peripheral sites, which is consistent with bottom-up progression. α-Synuclein seed amplification assays further corroborate the association between the peripheral α-synuclein burden and reduced 123I-MIBG uptake. While 123I-MIBG myocardial scintigraphy is a promising tool, its limitations include cost, limited availability, and potential confounding from underlying cardiac conditions. Nonetheless, early detection of cardiac sympathetic denervation via 123I-MIBG imaging may enhance diagnosis, support subtype classification, and improve the understanding of PD pathogenesis.

Purpose: The purpose of this study was to determine scanning accuracy (precision) of an intraoral scanner according to surface roughness of the prepared abutment models and to identify the most advantageous tooth surface roughness for scanning. Materials and methods: Using Computer-Aided Design (CAD) software (Autodesk Meshmixer), four maxillary molar abutment models were designed to fit the maxillary dentiform and printed with Polymethylmethacrylate (PMMA) (MAZIC D temp) using a 3D printer (Carima IMD). The teeth were fixed to the dentiform. Each model was prepared with four diamond burs of different grit sizes:Coarse (125 – 150 µm), Medium (106 – 125 µm), Fine (53 – 63 µm), and Extra-fine (20 – 30 µm), producing four abutment groups (group G, B, R, Y). Each model was scanned twice with an intraoral scanner (Primescan), generating paired scan files that were overlapped and aligned. This was repeated ten times, yielding 20 files (10 pairs) per model. The precision of the 10 pairs was evaluated with 3D analysis software (GOM Inspect 2018). A point guide created with Autodesk Meshmixer was used to analyze deviations at 14 fixed points. The analysis was conducted from three perspectives: First, whether precision differed as surface roughness changed; second, whether there was a difference in precision between the seven upper and seven lower points in each model; third, whether the presence and direction of adjacent teeth influenced precision, assessed by deviations at mesial, distal, buccal, and palatal points. Differences in mean deviations among the groups and the directions were statistically analyzed using ANOVA (α = 0.05), and the differences between the upper and lower points were analyzed using an independent samples T-test (α = 0.05). Results: Deviations according to abutment surface roughness were lowest in group Y, followed by R, B, and G (P < .05). No statistical significance was observed between the seven upper and seven lower points in groups G, B, R, and Y (P > .05). To determine differences in scan precision by directions, points on the same horizontal plane were grouped, and mean deviations among the seven groups were compared. No statistical significance was found (P> .05). Conclusion When preparing an abutment for prosthesis restoration, the consistency and precision of intraoral scan improve as the surface roughness decreases and angled areas are finished smoothly. In addition, if a skilled operator performs the intraoral scan consistently, there is no significant difference in scan precision according to the location of the scanned point.

Background/Aims: Patients with concurrent type 2 diabetes mellitus (T2DM) and metabolic dysfunction-associated steatotic liver disease (MASLD) face elevated cardiovascular risks. However, optimal oral antidiabetic drug (OAD) selection for this population remains unclear. Methods: Using the Korean National Health Information Database, we conducted a target trial emulation comparing cardiovascular outcomes among patients with T2DM and MASLD (defined by fatty liver index ≥30) who initiated sodium-glucose cotransporter 2 (SGLT2) inhibitors, thiazolidinediones, dipeptidyl peptidase-4 (DPP-4) inhibitors, or sulfonylureas with metformin. The primary outcome was major adverse cardiovascular events (MACE), including cardiovascular mortality, nonfatal myocardial infarction, and nonfatal stroke. Results: Among 71,071 patients (331,726 person-years), SGLT2 inhibitor users experienced a significantly lower MACE risk compared to sulfonylurea users (adjusted subdistribution hazard ratio [aSHR], 0.44; 95% confidence interval [CI], 0.31–0.62). SGLT2 inhibitors also demonstrated a lower MACE risk compared to thiazolidinediones (aSHR, 0.61; 95% CI, 0.39–0.96) and DPP-4 inhibitors (aSHR, 0.59; 95% CI, 0.42–0.96). Cardiovascular mortality risk was notably reduced with SGLT2 inhibitors compared to sulfonylureas (aSHR, 0.13; 95% CI, 0.03–0.50), thiazolidinediones (aSHR, 0.19; 95% CI, 0.04–0.86), and DPP-4 inhibitors (aSHR, 0.22; 95% CI, 0.06–0.84). Mediation analysis revealed that MASLD regression accounted for 8.7% of the total cardiovascular benefit when comparing SGLT2 inhibitors to sulfonylureas. Conclusions In patients with concurrent T2DM and MASLD, SGLT2 inhibitors demonstrated better cardiovascular outcomes compared to other OADs. These findings suggest that SGLT2 inhibitors may be the preferred OAD choice for cardiovascular risk reduction in this high-risk population.

Background and Objectives: Clinical characteristics and outcomes in acute heart failure (AHF) vary by phenotype. We assessed phenotype-specific features, treatment patterns, and outcomes in a nationwide Korean cohort. Methods: The Korean Heart Failure III registry prospectively enrolled 7,351 AHF admissions at 47 hospitals. Among 6,777 patients with available left ventricular ejection fraction (EF), phenotypes were defined as heart failure with reduced EF (HFrEF, ≤40%), mildly reduced EF (HFmrEF,41–49%), or preserved EF (HFpEF, ≥50%). The primary endpoint was a 12-month composite of all-cause death or heart transplantation, evaluated from index admission and, among hospital survivors, from discharge. We used inverse probability weighting (multinomial generalized boosted models with stabilized, trimmed weights) and weighted Cox proportional-hazards models to estimate hazard ratios (HRs). Results: Phenotype distribution was 58.9% HFrEF, 13.6% HFmrEF, and 27.5% HFpEF. Crude 12-month composite rates from index admission were 13.4% (HFrEF), 12.7% (HFmrEF), and 16.8% (HFpEF). After weighting, from index admission, HFmrEF (HR, 0.892; 95% confidence interval [CI], 0.731–1.088) and HFpEF (HR, 1.101; 95% CI, 0.939–1.291) did not differ from HFrEF; from discharge, HFpEF had modestly higher risk (HR, 1.207; 95% CI, 1.008–1.445) whereas HFmrEF did not (HR, 1.039; 95% CI, 0.844–1.279). Hyponatremia and chronic kidney disease were consistent adverse markers, while angiotensin-converting enzyme inhibitor/ angiotensin II receptor blocker use at discharge was protective. Conclusions Across the EF spectrum, phenotypes showed distinct profiles and risk. Postdischarge risk was modestly higher in HFpEF, supporting phenotype-tailored care and systematic discharge optimization in Korean patients with AHF.

Heart failure (HF) prevalence and associated socio-economic costs have risen rapidly in Korea, creating urgent demand for a national, standardized prospective registry to support quality monitoring, outcome comparison, and real-world evidence. Standardized data definitions are essential for valid comparisons across studies and healthcare settings. We created a unified national HF cohort by integrating the two largest Korean registries, KorAHF (2011–2014;n=5,625) and KorHF III (2018–2023; n=7,351), yielding 12,976 hospitalized HF patients. Because heterogeneous variable definitions impeded direct comparisons, we implemented a harmonization pipeline across demographic, clinical, imaging, biomarker, therapeutic, and outcome domains, aligned with international standards and reinforced by systematic data quality checks.A multidisciplinary panel then conducted a structured decision process to produce the Korean HF Standard Dataset, a tiered and interoperable variable set spanning six domains: demographics, presentation at admission, in-hospital events and comorbidities, discharge status, outpatient follow-up, and readmission events. This integrated platform and standardized variables enable precise identification of HF patient phenotypes and prognostic factors, establishing an evidence-based foundation for disease management. This supports an analysis of temporal changes in treatment patterns and outcomes, generates data to inform future clinical practice guidelines, and provides a practical basis for planning large, continuous, prospective HF registries. Furthermore, it also facilitates pragmatic, registry-based randomized clinical trials and unmet-needs assessments that can guide national health policy. Establishing a foundation for future linkage with national health databases, this platform will allow for enhanced accuracy, comparability, and representativeness, powering quality improvement initiatives and population-level monitoring of Korea’s growing HF burden.

Background and Objectives: Heart failure (HF) imposes a significant global burden, yet awareness and implementation of guideline-directed management remain suboptimal. This study evaluated HF awareness, diagnostic patterns, and therapeutic strategies among physicians in Korea. Methods: A nationwide online survey was conducted from July to August 2019, targeting primary care physicians (PCPs; n=8,000) and hospital-based cardiology specialists (n=1,339) across Korea. The questionnaire comprised 23 items covering baseline characteristics, perceptions of HF prognosis, diagnostic approaches, and treatment practices. Results: A total of 543 physicians responded (209 PCPs and 334 cardiology specialists). While the majority correctly defined HF, a substantial proportion underestimated the lifetime risk and poor prognosis. Cardiology specialists were more likely than PCPs to use objective diagnostic tools, including echocardiography (97% vs. 61%, p<0.001) and natriuretic peptide testing (90% vs. 57%, p<0.001). Among PCPs, 29% reported diagnosing HF based on symptoms and physical findings without objective testing, and 27% reported referring patients to general hospitals for diagnostic evaluation. Prescription rates for guideline-directed medical therapies, including renin-angiotensin system blockers and beta-blockers, were consistently higher among cardiology specialists.PCPs more frequently cited advanced age as a barrier to prescribing evidence-based medications. Conclusions Physicians’ awareness and clinical practices regarding HF in Korea remain suboptimal. Given the growing burden, high mortality, and substantial costs of HF, early detection, appropriate diagnostic evaluation, and timely referral are essential. Targeted education and system-level strategies to improve guideline implementation, particularly in primary care settings, are warranted.

The brain-derived neurotrophic factor (BDNF) plays a crucial role in neuroprotection, and we have previously demonstrated BDNF-mediated neuroprotective effects in mesenchymal stromal cells (MSCs). The present study aimed to investigate whether BDNF-overexpressing MSCs enhance the therapeutic efficacy of naïve MSCs in a preclinical model of severe neonatal intraventricular hemorrhage (IVH). We exposed primary rat neuronal cells to 40 U of thrombin overnight in vitro. Subsequently, the neuronal cells were co-cultured with either naïve MSCs or BDNF-overexpressing MSCs (1×105 cells in 1 mL media) for 24 hours. Next, 300 μL of maternal blood was injected into bilateral ventricles on postnatal day (P)4 to induce severe IVH in newborn Sprague-Dawley male rats. At P6, either naïve MSCs or BDNF-overexpressing MSCs (1×105 cells in 10 μL saline) were transplanted intraventricularly. Behavioral function tests, including passive avoidance, followed by endpoint analyses of brain tissue and cerebrospinal fluid were performed at P35. BDNF-overexpressing MSCs enhanced the effects of naïve MSCs against cell death, cytotoxicity, and oxidative stress in vitro. Notably, naïve and BDNF-overexpressing MSCs did not attenuate post-hemorrhagic ventricular dilatation, neuronal cell death, or gliosis. However, BDNF-overexpressing MSCs attenuated microglial activation.Furthermore, inflammatory cytokine (interleukin [IL]-1α, IL-1β, IL-6, and tumor necrosis factor-α) levels and memory function assessed using a passive avoidance test significantly improved in the BDNF-overexpressing MSC transplanted group compared with the naïve MSC transplanted group. Our data suggest that BDNF-overexpressing MSCs may offer superior protective effects to naïve MSCs in a neonatal IVH model.

Extracellular vesicles (EVs) are crucial mediators of intercellular communication, which facilitate the transfer of bioactive molecules such as proteins, lipids, and nucleic acids. Their high biocompatibility and intrinsic targeting abilities make them promising candidates for therapeutics, drug delivery, and disease biomarkers. In liver diseases, EVs are essential in liver regeneration, fibrosis modulation, and ischemia-reperfusion injury repair, and EV-derived biomarkers have shown potential for non-invasive disease monitoring, particularly in hepatitis B virus infection, non-alcoholic fatty liver disease, and hepatocellular carcinoma. This review provides a comprehensive overview of EV biology, cellular sources, isolation techniques, and strategies to enhance their therapeutic potential. Furthermore, we discuss the role of EVs in liver regeneration and their clinical application in biomarker discovery. Despite significant advancements in EV-based therapies, challenges such as scalability, standardization, immunogenicity, and regulatory approval remain key hurdles for clinical translation. Future research should focus on optimizing EV bioengineering, refining isolation methods, and addressing regulatory concerns to facilitate successful application of EVs in liver disease management and precision medicine.

In patients with differentiated thyroid cancer (DTC), initial recurrence risk stratification based on clinical, histopathological, and perioperative data remains the key determinant for guiding management strategies during the first 1-2 years post-treatment. However, the adoption of ongoing risk stratification (ORS), which dynamically reassesses risk by integrating longitudinal clinical data and treatment response, enables more precise long-term prognostic assessment and facilitates highly individualized management. Building upon recent guidelines, the 2026 KTA guideline has been further refined by incorporating robust evidence from large-scale national cohorts and comprehensive systematic reviews. These updated recommendations outline contemporary concepts of ORS, risk-adapted TSH suppression targets, optimized surveillance modalities for recurrence detection, and disease-specific long-term follow-up strategies. Reflecting the paradigm shift toward de-escalated treatment, this revision integrates evolved perspectives on TSH suppression intensity, the clinical interpretation of thyroglobulin levels, and tailored follow-up intervals. These evidence-based recommendations aim to minimize unnecessary treatment and excessive surveillance in the large proportion of patients with excellent prognosis after initial therapy, while ensuring that each patient receives appropriately tailored and effective long-term management.

Purpose: To assess the accuracy of supraspinatus muscle fat fraction and atrophy measured on the Y-view compared with the newly proposed fossa-view sagittal MRI plane. Materials and Methods: This study included 84 patients (36 male; mean age, 65.1 ± 10.1 years) who underwent shoulder MRI with extended oblique sagittal T1-weighted and three-dimensional (3D) six-echo Dixon imaging between December 2020 and November 2022. The reference fat fraction was calculated by integrating voxel-wise Dixon values, while supraspinatus muscle volume was quantified using a 3D nnU-Net algorithm and normalized to the scapular volume to derive the standardized muscle index (SMI). Fat fraction and cross-sectional area were quantified on the Y-view and fossaview and compared with the reference values. Subgroup analyses were performed using fatty degeneration and retraction grades. Results: Agreement with the reference fat fraction was significantly higher for the fossa-view (intraclass correlation coefficient [ICC], 0.923) than for the Y-view (ICC, 0.822;p = 0.006). The fossa-view showed smaller deviations and narrower limits of agreement.For SMI, the Y-view (ICC, 0.782) showed higher agreement than the fossa-view (ICC, 0.694), although the difference was not statistically significant (p = 0.219). Subgroup analyses showed better Y-view performance at lower retraction grades and better fossa-view performance at higher grades, although the differences were not statistically significant (all p > 0.05). Conclusion Both planes reliably quantified the fat fraction with greater accuracy in the fossa-view. However, single-plane assessment of muscle atrophy was less reliable, underscoring the need for MRI evaluation of the entire muscle.