The detrimental effects of hyperlipidemia on the healing of rotator cuff tears are well documented. The proposed underlying mechanisms for these effects include alterations in the extracellular matrix, inflammation, and oxidative stress, which hamper the reparative processes in the affected tendon tissues. Recent therapeutic strategies target these pathways, reflecting a growing body of research dedicated to mitigating these effects and promoting healing. This literature review aims to provide a comprehensive understanding of the pathophysiology underlying rotator cuff tears, examine the interplay between hyperlipidemia and rotator cuff tear healing, synthesize current knowledge on contributing biological mechanisms, and outline potential therapeutic interventions to optimize clinical management and treatment outcomes for patients.

Background: This study aimed to investigate changes after repeated subacromial drug injections in a rat model of normal rotator cuff. Methods: Thirty-nine male Sprague-Dawley rats were divided into groups 1 (no injection, n = 3), 2 (parecoxib, n = 18; 6 subgroups, n = 3 each; 0.5 mg/kg), and 3 (triamcinolone, n = 18; 6 subgroups, n = 3 each; 0.3 mg/kg). Groups 2 and 3 received subacromial injections 1–6 times once weekly for 6 weeks. The supraspinatus and infraspinatus tendons and muscles were used for biomechanical and histological evaluation. The subacromial bursa was used to analyze the prostaglandin E2 (PEG2) level. Results: In the biomechanical test, load-to-failure and ultimate stress decreased in groups 2 and 3 with repeated injections and the values were significantly lower in group 3 than in group 1 only at the sixth injection (p = 0.007 and p = 0.008, respectively). On the Bonar score, the cellularity, ground substance, and total score were significantly different among the 3 groups at the fifth and sixth injections (cellularity: p = 0.028 and p = 0.033, ground substance: p = 0.018 and p = 0.006, and total score: p = 0.029 and p = 0.027, respectively). The myocyte cross-sectional area of the infraspinatus muscle showed a significant difference among the 3 groups at the third and fourth injections (p = 0.031 and p = 0.020, respectively). The PEG2 level in the subacromial bursa was significantly different among the 3 groups at the third, fifth, and sixth injections (p = 0.019, p = 0.004, and p = 0.004, respectively). Conclusions In the rat model of normal rotator cuff, repeated local injections of the cyclooxygenase-2 inhibitor showed fewer negative effects on the biomechanical and histological properties of the normal tendon than triamcinolone.

Background: Several studies have investigated the morphological risk factors contributing to posterior cruciate ligament (PCL) injury. However, no study has focused on the injury patterns of intrasubstance tears or tibial avulsion fractures in relation to morphologies and regional bone quality. This study aimed to investigate the impact of the knee morphology and regional bone quality of the proximal tibia on the PCL injury pattern. Methods: This retrospective study compared the radiological features of 76 patients with PCL injuries (PI group) and 76 matched patients with normal PCL (control group). The PI group was divided into 2 subgroups: PCL avulsion fracture (PAF subgroup; n = 43) and PCL intrasubstance tear (PIT subgroup; n = 33). Measurements included the coronal notch width index, coronal tibial slope, medial and lateral posterior tibial slopes, and medial tibial depth. Three Hounsfield unit average measurements were taken from the proximal tibia around the PCL insertion site to create a summative measure of overall bone quality. Results: The medial tibial depth and coronal notch width index were significantly lower in the PI group than those in the control group (medial tibial depth: 2.04 ± 0.77 vs. 3.02 ± 1.04, p = 0.017; coronal notch width index: 0.21 ± 0.03 vs. 0.24 ± 0.03, p = 0.041). In the subgroup analysis, medial tibial depth and Hounsfield unit were significantly lower in the PAF subgroup than in the PIT subgroup (medial tibial depth: 1.74 ± 0.66 vs. 2.43 ± 0.77, p = 0.008, Hounsfield unit: 89.48 ± 31.73 vs. 120.15 ± 29.24, p = 0.004). Binary logistic regression analysis showed that medial tibial depth (odds ratio [OR], 0.161; p < 0.001) and Hounsfield unit (OR, 0.950;p < 0.001) were independent risk factors for PCL tibial avulsion fractures. Conclusions Lower notch width index and medial tibial depth are associated with PCL injuries. Shallower medial tibial depth and lower Hounsfield unit measurements around the PCL insertion site were associated with an increased incidence of PCL avulsion fractures. These findings may assist clinicians in identifying patients at risk of distinct PCL injury patterns.

Background/Aims: The incidence of steatotic liver disease (SLD) is increasing across all age groups as the incidence of obesity increases worldwide. The existing noninvasive prediction models for SLD require laboratory tests or imaging and perform poorly in the early diagnosis of infrequently screened populations such as young adults and individuals with healthcare disparities. We developed a machine learning-based point-of-care prediction model for SLD that is readily available to the broader population with the aim of facilitating early detection and timely intervention and ultimately reducing the burden of SLD. Methods: We retrospectively analyzed the clinical data of 28,506 adults who had routine health check-ups in South Korea from January to December 2022. A total of 229,162 individuals were included in the external validation study. Data were analyzed and predictions were made using a logistic regression model with machine learning algorithms. Results: A total of 20,094 individuals were categorized into SLD and non-SLD groups on the basis of the presence of fatty liver disease. We developed three prediction models: SLD model 1, which included age and body mass index (BMI); SLD model 2, which included BMI and body fat per muscle mass; and SLD model 3, which included BMI and visceral fat per muscle mass. In the derivation cohort, the area under the receiver operating characteristic curve (AUROC) was 0.817 for model 1, 0.821 for model 2, and 0.820 for model 3. In the internal validation cohort, 86.9% of individuals were correctly classified by the SLD models. The external validation study revealed an AUROC above 0.84 for all the models. Conclusions As our three novel SLD prediction models are cost-effective, noninvasive, and accessible, they could serve as validated clinical tools for mass screening of SLD.

Background/Aims: Fibronectin (FN) has recently been identified as being overexpressed in patients with hepatocellular carcinoma (HCC) and deemed a promising biomarker of vascular invasion. The aim of this study was to examine the patterns of FN expression in HCC cells and their clinicopathological significance, such as their association with vascular invasion and angiogenesis patterns. Methods: Immunohistochemical analysis of FN was conducted using tissue microarrays from 258 surgically resected HCCs and matched nontumorous liver tissues. Three distinct FN expression patterns were observed: cytoplasmic, membranous, and sinusoidal. Moderate or strong expression was considered FN-positive. Results: Cytoplasmic or sinusoidal FN expression was significantly more common in HCC cells than in the adjacent liver tissue (p<0.001). FN expression was detected in the membranes of HCC cells and absent in nonneoplastic hepatocytes (p<0.001). Overall survival and disease-free survival in patients with HCC cells with membranous FN expression were significantly shorter than those in patients without membranous FN expression. Membranous FN expression in HCC was significantly associated with high serum alpha-fetoprotein (AFP) and protein induced by vitamin K absenceII (PIVKA-II) levels, infiltrative gross type, poor Edmondson-Steiner grade, major vessel invasion, microvascular invasion, macrotrabecular massive subtype, advanced T stage, and vessel-encapsulating tumor cluster pattern. Sinusoidal pattern of FN expression in HCC was significantly associated with high serum AFP and PIVKA-II levels, infiltrative gross type, large tumor size, microvascular invasion, macrotrabecular massive subtype, and vessel-encapsulating tumor cluster patterns. Conclusions Evaluating FN expression in HCC cells may be useful for identifying aggressive cases of HCC with vascular invasion via biopsy.

Background/Aims: This study aimed to evaluate the performance of the Model for End-Stage Liver Disease (MELD) 3.0 for predicting mortality and liver-related complications compared with the Child-Pugh classification, albumin-bilirubin (ALBI) grade, the MELD, and the MELD sodium (MELDNa) score. Methods: We evaluated a multicenter retrospective cohort of incorporated patients with cirrhosis between 2013 and 2019. We conducted comparisons of the area under the receiver operating characteristic curve (AUROC) of the MELD3.0 and other models for predicting 3-month mortality. Additionally, we assessed the risk of cirrhosis-related complications according to the MELD3.0 score. Results: A total of 3,314 patients were included. The mean age was 55.9±11.3 years, and 70.2% of the patients were male. Within the initial 3 months, 220 patients (6.6%) died, and the MELD3.0had the best predictive performance among the tested models, with an AUROC of 0.851, outperforming the Child-Pugh classification, ALBI grade, MELD, and MELDNa. A high MELD3.0score was associated with an increased risk of mortality. Compared with that of the group with a MELD3.0 score <10 points, the adjusted hazard ratio of the group with a score of 10–20 pointswas 2.176, and that for the group with a score of ≥20 points was 4.892. Each 1-point increase inthe MELD3.0 score increased the risk of cirrhosis-related complications by 1.033-fold. The risk of hepatorenal syndrome showed the highest increase, with an adjusted hazard ratio of 1.149, followed by hepatic encephalopathy and ascites. Conclusions The MELD3.0 demonstrated robust prognostic performance in predicting mortality in patients with cirrhosis. Moreover, the MELD3.0 score was linked to cirrhosis-related complications, particularly those involving kidney function, such as hepatorenal syndrome and ascites.

Background/Aims: The study investigated the incidence, risk factors, and clinical outcomes of chronic antibiotic-refractory pouchitis (CARP) in Korean patients with ulcerative colitis (UC). Methods: This single-center retrospective study included patients with UC who underwent total proctocolectomy with ileal pouch-anal anastomosis at the Asan Medical Center in Korea between January 1987 and December 2022. The primary outcomes were endoscopic remission and pouch failure. The Cox’s proportional hazard model was used to identify the risk factors for CARP. Results: The clinical data of 232 patients were analyzed. The most common cause of surgery was steroid refractoriness (50.9%), followed by dysplasia/colorectal cancer (26.7%). Among 74 patients (31.9%) with chronic pouchitis (CP), 31 (13.4%) had CARP, and 43 (18.5%) had chronic antibiotic-dependent pouchitis (CADP). The most frequent endoscopic phenotype was focal inflammation of the pouch (CP, 47.3%; CARP, 35.5%; CADP, 55.8%). Patients with CARP were less likely to use concomitant probiotics than patients with CADP (29.0% vs 72.1%, p<0.01). The endoscopic remission rate of CP, CARP, and CADP was 14.9%, 9.7%, and 18.6%, respectively.The pouch failure rate associated with CP, CARP, and CADP was 13.5%, 16.1%, and 11.6%, respectively. Current smoking status (adjusted hazard ratio [aHR], 2.96; 95% confidence interval [CI], 1.27 to 6.90; p=0.01) and previous use of biologics/small molecules (aHR, 2.40; 95% CI, 1.05 to 5.53; p=0.04) were significantly associated with CARP development. Conclusions UC patients who were current smokers and previously used biologics/small molecules had a higher risk of developing CARP. Concomitant use of probiotics was less likely to be associated with CARP development.

Systemic corticosteroids play an essential role in the management of asthma. During acute exacerbation, the short-term use of systemic corticosteroids is recommended. For patients with uncontrolled asthma and severe asthma, long-term and low-dose oral corticosteroids (OCS) have frequently been advocated. However, both short-term and long-term use of systemic corticosteroids carry the risk of adverse events (AEs), including various morbidities and even mortality. Despite recent progress in adult severe asthma management and the availability of new treatment options, the current domestic guidelines for asthma do not provide specific recommendations for oral corticosteroid tapering in patients with severe asthma. Therefore, the task force team of the severe asthma working group in the Korean Academy of Allergy, Asthma, and Clinical Immunology has proposed a tapering protocol for systemic corticosteroid use in severe asthma. This includes practical recommendations for monitoring OCS-related AE, particularly for adrenal insufficiency and osteoporosis, which suggests corticosteroid-sparing strategies that include alternative therapies, modifying treatable traits, timely specialist assessment, and shared decision-making with patients. However, further real-world research and collaboration with doctors from primary and academic institutes, patients, and policymakers are necessary to establish an OCS stewardship approach. This should include realistic OCS-tapering strategies for patients with severe asthma using regular OCS, education, and campaigns for patients, the public, and healthcare providers about the burden of severe asthma, as well as improving timely access to specialized severe asthma services for optimal management.

Atopic dermatitis is the most common chronic inflammatory skin disease in children and adolescents. The Korean Academy of Pediatric Allergy and Respiratory Disease published the Atopic Dermatitis Treatment Guideline in 2008, which has been helpful in atopic dermatitis treatment until now. Various reports on the development and effectiveness of new drugs have suggested that there is a need to develop and revise old treatment guidelines. Part 1 aimed to provide evidence-based recommendations for skin care management and topical treatment for atopic dermatitis. Part 2 focuses on systemic treatment, novel therapeutics, and adjuvant therapy. The goal of this guideline is intended to assist front-line doctors treating pediatric and adolescent atopic dermatitis patients make safer, more effective, and more rational decisions regarding systemic treatment, novel therapeutics, and adjuvant therapy by providing evidence-based recommendations with a clear level of evidence and benefit regarding treatment.

Purpose: Considering the high disease burden and unique features of Asian patients with breast cancer (BC), it is essential to have a comprehensive view of genetic characteristics in this population. An institutional targeted sequencing platform was developed through the Korea Research-Driven Hospitals project and was incorporated into clinical practice. This study explores the use of targeted next-generation sequencing (NGS) and its outcomes in patients with advanced/metastatic BC in the real world. Materials and Methods: We reviewed the results of NGS tests administered to BC patients using a customized sequencing platform—FiRST Cancer Panel (FCP)—over 7 years. We systematically described clinical translation of FCP for precise diagnostics, personalized therapeutic strategies, and unraveling disease pathogenesis. Results: NGS tests were conducted on 548 samples from 522 patients with BC. Ninety-seven point six percentage of tested samples harbored at least one pathogenic alteration. The common alterations included mutations in TP53 (56.2%), PIK3CA (31.2%), GATA3 (13.8%), BRCA2 (10.2%), and amplifications of CCND1 (10.8%), FGF19 (10.0%), and ERBB2 (9.5%). NGS analysis of ERBB2 amplification correlated well with human epidermal growth factor receptor 2 immunohistochemistry and in situ hybridization. RNA panel analyses found potentially actionable and prognostic fusion genes. FCP effectively screened for potentially germline pathogenic/likely pathogenic mutation. Ten point three percent of BC patients received matched therapy guided by NGS, resulting in a significant overall survival advantage (p=0.022), especially for metastatic BCs. Conclusion Clinical NGS provided multifaceted benefits, deepening our understanding of the disease, improving diagnostic precision, and paving the way for targeted therapies. The concrete advantages of FCP highlight the importance of multi-gene testing for BC, especially for metastatic conditions.