Rectal cancer, which accounts for approximately 40% of colorectal cancers, remains a major clinical concern. Recent advances in diagnostic imaging, surgical techniques, radiotherapy, and systemic treatment have steadily improved rectal cancer outcomes. Considering this, the Korean Rectal Cancer Multidisciplinary (KRCM) Committee has aimed to provide clinicians and policymakers with up-to-date, evidence-based clinical practice guidelines to support optimal decision-making, reflecting current evidence, the Korean healthcare context, and patient values and preferences. The Clinical Practice Guidelines for Rectal Cancer version 2.0 were developed through multidisciplinary collaboration with related academic societies, building upon and updating the KRCM Clinical Practice Guidelines version 1.0 (titled “Multidisciplinary guidelines for the management of rectal cancer”). These consensus guidelines of the KRCM were established based on a comprehensive literature review, evidence synthesis, with recommendation development guided by the GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodology, and consideration of applicability in real-world clinical practice under the national health insurance system. Each recommendation has been presented with its strength and level of evidence.

Alzheimer’s disease (AD) is characterized by progressive cognitive deterioration and significant depression. However, the mechanisms linking depression to AD pathology remain unclear. Here, we investigated whether Notch2 signaling mediates depressionlike behaviors in presenilin-2 (PS2) N141I mutant mice, an early-onset AD model. PS2 wild-type (WT) and mutant (MT) mice aged 12-15 months were subjected to unpredictable chronic mild stress (UCMS) for 4 weeks, followed by sucrose preference, tail-hanging, and forced swimming tests. Behavioral assessments showed that UCMS exacerbated anhedonia and immobility only in PS2 MT mice. Molecular analysis revealed concomitant increases in plasma corticosterone, hippocampal γ-secretase activity, and Notch2 expression, and elevated total and phosphorylated glucocorticoid receptor levels in PS2 MT-UCMS mice. Gene expression profiling of human hippocampal datasets confirmed upregulation of NOTCH2 in Alzheimer’s disease and depression.Pharmacological inhibition of γ-secretase and Notch signaling with DAPT normalizes depressive behavior, reduces corticosterone release, attenuates GR phosphorylation, and inhibits Notch2 signaling in PS2 MT mice. These findings identify Notch2 as a pivotal mediator linking chronic stress to molecular changes associated with depression and AD, and suggest that targeting Notch2 signaling may provide therapeutic benefits for comorbid mood and neurodegenerative disorders.

Background: Human muscle satellite (stem) cells (MuSCs) are essential for investigating muscle physiology, regeneration, and disease mechanisms. Primary cultures derived directly from human tissues offer a more physiologically relevant model than immortalized cell lines. However, the isolation and characterization of MuSCs from human upper limb tissues are limited. Therefore, this study aimed to establish and characterize a primary culture system for MuSCs obtained from human upper limb muscle tissue. Methods: Human muscle tissues were obtained from upper limb surgical specimens. Muscle samples were mechanically and enzymatically dissociated to isolate muscle-derived cells, which were cultured under standard growth conditions. Cell morphology and proliferation were monitored during the culture period. Myogenic characteristics were assessed by examining the expression of muscle-specific markers including myogenic regulatory factors and structural proteins. Additionally, myogenic differentiation capacity was evaluated by inducing differentiation and analyzing the formation of multinucleated myotubes. Results: Primary MuSCs were isolated from human upper limb tissues and expanded in vitro. The cultured cells exhibited a typical spindle-shaped morphology and demonstrated significant proliferative capacity. Characterization confirmed the expression of myogenic markers, indicating the presence of muscle-derived precursor cells. Following induction of differentiation, the cells formed multinucleated myotube-like structures and expressed muscle proteins associated with differentiation, highlighting their potential for myogenic differentiation. Conclusion This study established a reliable protocol for isolating and culturing MuSCs from human upper limb tissues. Cultured cells displayed typical myogenic characteristics and differentiation capacity, indicating that this model could be a valuable platform for studying human muscle biology and potential therapeutic applications.

Background: Clopidogrel requires several hours to achieve adequate platelet inhibition. We investigated the association of clopidogrel preloading time with 30-day clinical outcomes and post-procedural troponin elevation in patients with stable angina undergoing elective percutaneous coronary intervention (PCI). Methods: This single-center retrospective cohort study included 1,020 patients with stable angina (clopidogrel-naive) who received 300 mg clopidogrel preloading within 24 hours before elective PCI between 2012 and 2020. Patients were categorized according to clopidogrel preloading-to-balloon time ≤6 hours or >6 hours. The primary endpoint was 30-day major adverse cardiovascular events (MACE), defined as a composite of all-cause death, myocardial infarction, stroke, and any revascularization. Secondary endpoints included serial troponin T changes and troponin T elevation ≥5×, ≥25×, and ≥70× the upper reference limit. Stabilized inverse probability of treatment weighting (IPTW) was used. Results: Thirty-day MACE occurred in five patients (0.49%) and did not differ between the ≤6-hour and >6-hour groups after IPTW (0.5% vs. 0.4%, p=0.754). Post-procedural troponin T levels at 6, 24, and 48 hours were higher in the ≤6-hour group. Patients with shorter preloading-to-balloon times showed higher peak troponin T levels, with the greatest difference at the ≤1-hour cutoff (geometric mean ratio, 2.12; 95% confidence interval, 1.53–2.95; p<0.001) and progressive attenuation at longer cutoffs. Troponin T elevation ≥5× and ≥25× was more frequent in the ≤6-hour group, whereas ≥70× elevation did not differ. Conclusion Clopidogrel preloading ≤6 hours before elective PCI was not associated with increased 30-day MACE but was associated with lower-threshold post-procedural troponin T elevation.

Background: Dual antiplatelet therapy with aspirin and a P2Y12 inhibitor is standard after percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS); however, bleeding risk remains a major concern. Early discontinuation of aspirin due to potent P2Y12 inhibition may mitigate bleeding without increasing thrombotic events. Methods: The ASpirin-FREE therapy after successful percutaneous coronary intervention for acute coronary syndrome (ASFREE) study was an investigator-initiated, single-center, prospective, open-label, single-arm pilot study enrolling patients with ACS who underwent PCI with drug-eluting stents. All patients received a single loading dose of aspirin on the day of the PCI, followed by ticagrelor or prasugrel monotherapy. The primary efficacy endpoint was target vessel failure (TVF) at 12 months. The primary safety endpoint was definite stent thrombosis. Event rates are reported with 95% confidence intervals (CIs). Results: In total, 228 patients were enrolled. TVF occurred in 10 patients (4.4%; 95% CI, 2.1%–7.9%). Definite stent thrombosis was observed in one patient (0.4%; 95% CI, 0.01%–2.4%), with no acute or subacute events. Major bleeding (Bleeding Academic Research Consortium type 3 or 5) occurred in two patients (0.9%; 95% CI, 0.1%–3.1%). Conclusion An aspirin-free strategy following a single loading dose with continuation of potent P2Y12 inhibitor monotherapy was feasible in patients with ACS undergoing PCI and was associated with low rates of thrombotic and major bleeding events. These findings should be regarded as hypothesis-generating and supporting further evaluations in adequately powered randomized controlled trials (CRIS registration: KCT0008182).

The efficacy of clarithromycin-containing triple therapy (TT) against Helicobacter pylori has declined in Korea, with recent first-line eradication rates falling below 70%. Clarithromycin resistance exceeded 30%, undermining the standard regimen for H. pylori. These trends necessitate a change in the treatment strategy. This review analyzed the shift proposed in the draft of the 2025 Korean H. pylori guidelines. We examined the rationale for abandoning TT as a first-line empirical therapy and the establishment of a new dual-pillar strategy: 1) the declining role of clarithromycin-containing TT as a first-line treatment and 2) polymerase chain reaction (PCR)-based tailored therapy as the recommended precision approach. We explored the 1) emergence of new empirical regimen options, 2) application of tailored therapy, and 3) adoption of potassium-competitive acid blockers (P-CABs). Empirical regimens have shifted toward four-drug combinations to achieve higher cure rates. Concomitant therapy (proton-pump inhibitor [PPI] or P-CAB+amoxicillin+clarithromycin+metronidazole) offers high efficacy but raises concerns about antibiotic overuse. As a compromise, bismuth-augmented triple regimens (adding bismuth to TT) are now recommended; these modified quadruple therapies (e.g., PACB: PPI+amoxicillin+clarithromycin+bismuth, or PAMB: PPI+amoxicillin+metronidazole+bismuth) significantly improve eradication rates without requiring a third antibiotic class. Regarding tailored therapy, PCR-based domestic clinical research data consistently achieves ≥90% cure rates in first-line treatment—markedly higher than empirical TT in Korea. Economic analyses supported the cost-effectiveness of this approach. The guideline algorithm for salvage therapy was clarified. Bismuth quadruple therapy has been confirmed as the standard second-line treatment. For third-line therapy, we analyzed the efficacy of levofloxacin-based regimens, rifabutin-based therapy, and bismuth add-on therapy with two previously unused antibiotics. The 2025 Korean guidelines establish quadruple therapies as the new standard through a dual strategy: pragmatic empirical treatment and PCR-guided tailored therapy, with P-CABs and bismuth-based regimens as key components.

Background: Posterior reversible encephalopathy syndrome (PRES) is a rare complication of lung transplantation with poorly understood risk factors and clinical characteristics. This study aimed to examine the occurrence, risk factors, and clinical data of patients who developed PRES following lung transplantation. Methods: A retrospective analysis was conducted on 147 patients who underwent lung transplantation between February 2013 and December 2023. The patients were diagnosed with PRES based on the clinical symptoms and radiological findings. We compared the baseline characteristics and clinical information, including primary lung diseases and immunosuppressive therapy related to lung transplantation operations, between the PRES and non-PRES groups. Results: PRES manifested in 7.5% (n=11) of the patients who underwent lung transplantation, with a median onset of 15 days after operation. Seizures were identified as the predominant clinical manifestation (81.8%, n=9) in the group diagnosed with PRES. All patients diagnosed with PRES recovered fully. Patients with PRES were significantly associated with connective tissue disease-associated interstitial lung disease (45.5% vs. 18.4%, P=0.019, odds ratio=9.808; 95% CI, 1.064–90.386; P=0.044). Nonetheless, no significant variance was observed in the type of immunotherapy, such as the use of calcineurin inhibitors, blood pressure, or acute renal failure subsequent to lung transplantation. Conclusions PRES typically manifests shortly after lung transplantation, with seizures being the predominant initial symptom. The presence of preexisting connective tissue disease as the primary lung disease represents a significant risk factor for PRES following lung transplantation.

Background: Atopic dermatitis (AD) is a common skin disease with a wide range of symptoms. Due to the rapidly changing treatment landscape, regular updates to clinical guidelines are needed. Objective: This study aimed to update the guidelines for the treatment of AD to reflect recent therapeutic advances and evidence-based recommendations. Methods: The Patient characteristics, type of Intervention, Control, and Outcome framework was used to determine 48 questions related to AD management. Evidence was graded, recommendations were determined, and, after 2 voting rounds among the Korean Atopic Dermatitis Association (KADA) council members, consensus was achieved. Results: This guideline provides treatment guidance on advanced systemic treatment modalities for AD. In particular, the guideline offers up-to-date treatment recommendations for biologics and Janus-kinase inhibitors used in the treatment of patients with moderate to severe AD.It also provides guidance on other therapies for AD, along with tailored recommendations for children, adolescents, the elderly, and pregnant or breastfeeding women. Conclusion KADA’s updated AD treatment guidelines incorporate the latest evidence and expert opinion to provide a comprehensive approach to AD treatment. The guidelines will help clinicians optimize patient-specific therapies.

Background: Atopic dermatitis (AD) is a common skin disease with a wide range of symptoms. Due to the rapidly changing treatment landscape, regular updates to clinical guidelines are needed. Objective: This study aimed to update the guidelines for the treatment of AD to reflect recent therapeutic advances and evidence-based practices. Methods: The Patient characteristics, type of Intervention, Control, and Outcome framework was used to determine 48 questions related to AD management. Evidence was graded, recommendations were determined, and, after 2 voting rounds among the Korean Atopic Dermatitis Association (KADA) council members, consensus was achieved. Results: The guidelines provide detailed recommendations on foundational therapies, including the use of moisturizers, cleansing and bathing practices, allergen avoidance, and patient education. Guidance on topical therapies, such as topical corticosteroids and calcineurin inhibitors, is also provided to help manage inflammation and maintain skin barrier function in patients with AD. Additionally, recommendations on conventional systemic therapies, including corticosteroids, cyclosporine, and methotrexate, are provided for managing moderate to severe AD. Conclusion KADA’s updated AD guidelines offer clinicians evidence-based strategies focused on basic therapies, topical therapies, and conventional systemic therapies, equipping them to enhance quality of care and improve patient outcomes in AD management.