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: To identify the optimal surgical technique for single-level anterior cervical discectomy and fusion (ACDF), this study compared surgical outcomes and incidence of adjacent segment degeneration (ASD) in patients undergoing single-level ACDF using cage alone single-level fusion and plate fixation techniques. Methods: This single-center retrospective study (2003–2018) included patients who underwent single-level ACDF with either plate fixation (PLATE) or cage (CAGE) alone. The radiologic and clinical outcomes between the 2 surgical groups were compared over a 4-year follow-up period. Outcomes of interest included parameters related to range of motion, sagittal alignment, as well as fusion, subsidence, and ASD rates. Clinical outcomes were evaluated using the Neck Disability Index (NDI) and visual analog scale (VAS) for pain. Dysphagia and hoarseness rates were estimated based on medical records. Results: Forty-seven patients were included (n=17 in CAGE group). In the CAGE group, 94.1% of the patients had Bridwell grade 1 or 2, compared to 83.3% in the PLATE group (p = 0.396). Subsidence occurred in 12.5% and 3.6% of the CAGE and PLATE cases, respectively (p = 0.543). Segmental kyphosis progressed in the CAGE group compared to the PLATE group at 12, 24, and 48 months (p < 0.001). Radiographic ASD was observed in 41.2% and 30.0% of patients in the CAGE and PLATE groups, respectively, with a higher incidence in the upper segments for both groups. Preoperative NDI scores were similar between the groups; however, postoperatively, the CAGE group had significantly lower NDI scores (3.50 ± 2.74 vs. 8.00 ± 5.81) at 4 years (p = 0.020). Neck pain VAS scores also showed significant improvement in the CAGE group (2.33 ± 2.94) compared with that in the PLATE group (3.07 ± 2.31) at 4 years (p = 0.045). Both groups showed comparable arm pain VAS scores at 2 and 4 years postoperatively. Postoperative dysphagia occurred in 1 patient in the PLATE group, resolving almost completely by 1 year. Conclusions Single-level ACDF using a cage alone technique demonstrated favorable radiologic and clinical outcomes overall compared to plate-augmented ACDF. However, plate augmentation is recommended for patients with severe cervical kyphosis or those at high risk of subsidence.

Background: and Purpose: The Cognitive Impairment Screening Test in Korea (CIST-K) was designed to detect cognitive decline. Developed independently and widely used in Korea, it is yet to be validated with other screening tests. This study aimed to introduce normative data to the CIST-K and assess its clinical usefulness through correlation analysis with the Korean version of the Mini-Mental State Examination, 2nd edition (K-MMSE-2). Methods: We enrolled 85 participants from a tertiary university hospital in Korea, including patients diagnosed with mild cognitive impairment and Alzheimer’s disease by experienced neurologists. Both the CIST-K and K-MMSE-2 were administered to assess the cognitive function of the participants, with scores from each subtest of the neuropsychological tests compared. Results: Multivariate correlation analysis, which was adjusted for age, sex, and education level, revealed a significant correlation between the two tests in orientation, memory, and attention. However, no significant correlation was found between the two tests in visuospatial and language functions. Conclusions In conclusion, this study demonstrates that some subtests in the CIST-K align with corresponding scores on the K-MMSE-2. However, caution is advised when interpreting visuospatial and language test scores from the CIST-K. Further validity studies are necessary to enhance the sensitivity of each subtest.

Background: and Purpose: Plasma biomarkers, including phosphorylated tau (ptau217), glial fibrillary acidic protein (GFAP), and neurofilament light chain (NfL), are promising tools for detecting Alzheimer’s disease (AD) pathology. However, cross-laboratory reproducibility remains a challenge, even when using identical analytical platforms such as single-molecule array (Simoa). This study aimed to compare plasma biomarker measurements (ptau217, GFAP, and NfL) between 2 laboratories, the University of Gothenburg (UGOT) and DNAlink, and evaluate their associations with amyloid positron emission tomography (PET) imaging. Methods: Plasma biomarkers were measured using Simoa platforms at both laboratories:the UGOT and DNAlink Incorporation. Diagnostic performance for predicting amyloid PET positivity, cross-laboratory agreement, and the impact of normalization techniques were assessed. Bland-Altman plots and correlation analyses were employed to evaluate agreement and variability. Results: Plasma ptau217 concentrations exhibited strong correlations with amyloid PET global centiloid values, with comparable diagnostic performance between laboratories (area under the curve=0.94 for UGOT and 0.95 for DNAlink). Cross-laboratory agreement for ptau217 was excellent (r=0.96), improving further after natural log transformation. GFAP and NfL also demonstrated moderate to strong correlations (r=0.86 for GFAP and r=0.99 for NfL), with normalization reducing variability. Conclusions Plasma biomarker measurements were consistent across laboratories using identical Simoa platforms, with strong diagnostic performance and improved agreement after normalization. These findings support the scalability of plasma biomarkers for multicenter studies and underscore their potential for standardized applications in AD research and clinical practice.

Background: and Purpose: This clinical practice guideline provides evidence-based recommendations for treatment of dementia, focusing on cholinesterase inhibitors and N-methyl-D-aspartate (NMDA) receptor antagonists for Alzheimer’s disease (AD) and other types of dementia. Methods: Using the Population, Intervention, Comparison, Outcomes (PICO) framework, we developed key clinical questions and conducted systematic literature reviews. A multidisciplinary panel of experts, organized by the Korean Dementia Association, evaluated randomized controlled trials and observational studies. Recommendations were graded for evidence quality and strength using Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. Results: Three main recommendations are presented: (1) For AD, cholinesterase inhibitors (donepezil, rivastigmine, galantamine) are strongly recommended for improving cognition and daily function based on moderate evidence; (2) Cholinesterase inhibitors are conditionally recommended for vascular dementia and Parkinson’s disease dementia, with a strong recommendation for Lewy body dementia; (3) For moderate to severe AD, NMDA receptor antagonist (memantine) is strongly recommended, demonstrating significant cognitive and functional improvements. Both drug classes showed favorable safety profiles with manageable side effects. Conclusions This guideline offers standardized, evidence-based pharmacologic recommendations for dementia management, with specific guidance on cholinesterase inhibitors and NMDA receptor antagonists. It aims to support clinical decision-making and improve patient outcomes in dementia care. Further updates will address emerging treatments, including amyloid-targeting therapies, to reflect advances in dementia management.

Background: and Purpose: Empathy comprises cognitive and emotional components.However, the impairments in empathy among individuals with mild cognitive impairment (MCI) and dementia of the Alzheimer’s type (DAT) are not well understood, particularly in the context of depression, which may exacerbate these deficits. This study aimed to evaluate the effects of neurodegeneration and depression on empathetic abilities. Methods: The study included 31 healthy elderly (HE) individuals, 30 patients with amnestic multi-domain MCI (amMCI), and 30 patients with DAT. Empathy was assessed using the Korean-Multifaceted Empathy Test (K-MET), and the Interpersonal Response Index (IRI).Participants were classified as depressed or non-depressed using the Geriatric Depression Scale. A two-way MANOVA was conducted to examine differences in empathy based on group and depressive status. Results: A significant interaction between group and depressive status was found for both cognitive and emotional empathy on the K-MET, but not on the IRI. In the depressed group, cognitive empathy scores were lower in the order of HE, amMCI, and DAT. Similarly, in the non-depressed group, the HE group performed better than both amMCI and DAT, with no significant difference between the latter two. Regarding emotional empathy, the depressed HE group scored higher than both amMCI and DAT, with no significant difference between these groups. In the non-depressed group, emotional empathy declined in the order of HE, amMCI, and DAT. Conclusions These findings indicate that both neurodegeneration and depression significantly impair empathetic abilities, with declines in cognitive and emotional empathy evident at the MCI stage, regardless of depressive status.

Background: Given the association between nonalcoholic fatty liver disease and metabolic risks, a new term, metabolic dysfunction- associated steatotic liver disease (MASLD) has been proposed. We aimed to explore the association between MASLD and all-cause, cause-specific mortalities. Methods: We included individuals with steatotic liver disease (SLD) from the Korean National Health Insurance Service. Moreover, SLD was defined as a fatty liver index ≥30. Furthermore, MASLD, metabolic alcohol-associated liver disease (MetALD), and alcoholic liver disease (ALD) with metabolic dysfunction (MD) were categorized based on alcohol consumption and MD. We also analyzed all-cause, liver-, cancer-, hepatocellular carcinoma (HCC)- and cardiovascular (CV)-related mortalities. Results: This retrospective nationwide cohort study included 1,298,993 individuals aged 40 to 79 years for a mean follow-up duration of 9.04 years. The prevalence of MASLD, MetALD, and ALD with MD was 33.11%, 3.93%, and 1.00%, respectively. Relative to the “no SLD” group, multivariable analysis identified that MASLD (adjusted hazard ratio [aHR], 1.28; 95% confidence interval [CI], 1.26 to 1.31), MetALD (aHR, 1.38; 95% CI, 1.32 to 1.44), and ALD with MD group (aHR, 1.80; 95% CI, 1.68 to 1.93) have a significantly higher risk of all-cause mortality. Furthermore, MASLD, MetALD, ALD with MD groups showed higher liver-, cancer- and HCC-related mortality than “no SLD” group. While all-cause specific mortalities increase from MASLD to MetALD to ALD with MD, the MetALD group shows a lower risk of CV-related mortality compared to MASLD. However, ALD with MD group still have a higher risk of CV-related mortality compared to MASLD. Conclusion SLD is associated with an increased risk of all-cause, liver-, cancer-, HCC-, and CV-related mortalities.

Background: Insulin resistance (IR) is central to metabolic disorders and significantly influenced by diet. Studies on meal frequency (MF) and metabolic indicators have shown mixed results. This study explores the link between MF and IR in middle-aged and older adults. Methods: This prospective cohort study included 4,570 adults aged 40 to 69 years from the Korean Genome and Epidemiologic Study. MF were divided into two groups based on whether they consumed three or more, or fewer than three, meals daily. IR was evaluated using the homeostasis model assessment of insulin resistance (HOMA-IR); participants were classified as IR if their HOMA-IR value was ≥2.5. Multiple Cox proportional hazard regression analyses were conducted to examine the association between MF and the incidence of IR. Results: After adjusting for all variables, individuals in the MF ≥3 group showed a reduced incidence of IR compared to those in the MF <3 group (hazard ratio, 0.880; 95% confidence interval, 0.782 to 0.990). Additionally, subgroup analyses by sex, diabetes mellitus (DM), and body mass index (BMI) showed that this association persisted only in men, individuals without DM, and those with a BMI <25. Conclusion Our findings indicate that a higher MF among middle-aged and older adults is associated with a reduced incidence of IR. However, this association was maintained only in men, individuals without DM, and those without obesity.

Background: Studies on predictive markers of insulin resistance (IR) and elevated liver transaminases in children and adolescents are limited. We evaluated the predictive capabilities of the single-point insulin sensitivity estimator (SPISE) index, metabolic score for insulin resistance (METS-IR), homeostasis model assessment of insulin resistance (HOMA-IR), the triglyceride (TG)/ high-density lipoprotein cholesterol (HDL-C) ratio, and the triglyceride-glucose index (TyG) for IR and alanine aminotransferase (ALT) elevation in this population. Methods: Data from 1,593 participants aged 10 to 18 years were analyzed using a nationwide survey. Logistic regression analysis was performed with IR and ALT elevation as dependent variables. Receiver operating characteristic (ROC) curves were generated to assess predictive capability. Proportions of IR and ALT elevation were compared after dividing participants based on parameter cutoff points. Results: All parameters were significantly associated with IR and ALT elevation, even after adjusting for age and sex, and predicted IR and ALT elevation in ROC curves (all P<0.001). The areas under the ROC curve of SPISE and METS-IR were higher than those of TyG and TG/HDL-C for predicting IR and were higher than those of HOMA-IR, TyG, and TG/HDL-C for predicting ALT elevation. The proportions of individuals with IR and ALT elevation were higher among those with METS-IR, TyG, and TG/ HDL-C values higher than the cutoff points, whereas they were lower among those with SPISE higher than the cutoff point. Conclusion SPISE and METS-IR are superior to TG/HDL-C and TyG in predicting IR and ALT elevation. Thus, this study identified valuable predictive markers for young individuals.