Sarcopenia, an age-related muscle atrophy disease, is a major health concern in aging societies and is closely associated with severe chronic diseases. Its primary pathogenesis involves oxidative stress-induced apoptosis in muscle cells and an imbalance in protein metabolism. This study evaluated the potential of Rhododendron mucronulatum branch extract (RMB) and its major flavonoids, taxifolin-3-O-arabinopyranoside (Tax-G) and taxifolin (Tax-A), as natural therapeutic agents for sarcopenia. Phytochemical analyses were performed using TLC, HPLC, LC-MS/MS, and NMR, and Tax-G and Tax-A were isolated from RMB. In vitro models of apoptosis and muscle atrophy were established in C2C12 cells using H2O2 and dexamethasone (DEX), respectively. Cell viability, myotube diameter, and protein expression related to apoptosis and muscle differentiation were assessed. All three substances reduced H2O2-induced apoptosis by increasing Bcl-2 and inhibiting cleaved caspase-3 and PARP. They also attenuated DEX-induced muscle atrophy by suppressing Atrogin-1, MuRF1, and FoxO3α while promoting MyoD, Myogenin, Akt, and mTOR. Although Tax-A showed the highest activity, Tax-G exhibited comparable effects with lower cytotoxicity. These findings demonstrate that RMB and its active compounds protect muscle cells by regulating apoptosis and muscle metabolism, suggesting their potential as safe and functional natural materials for the prevention of sarcopenia.
This study investigated the interplay between precipitate evolution and mechanical properties in a friction stir welded (FSW) AA7075 alloy, with emphasis on the effects of pin length, spindle speed, traverse speed, and axial force. The maximum ultimate tensile strength (UTS) of 430 MPa was obtained at a pin length of 3.5 mm and 800 rpm, whereas increasing the pin length to 4.1 mm reduced the UTS to 300 MPa. High-resolution transmission electron microscopy (HRTEM) revealed a clear structure-property correlation: lower heat input promoted the phase transformation of Al2Cu (theta) to Al2CuMg (S phase), strengthening the weld, while higher heat input destabilized the S phase and coarsened MgZn2 and Al2Cu precipitates, thereby reducing strength. Two machine learning algorithms, Random Forest (RF) and Extreme Gradient Boosting (XGB), were employed to optimize the welding conditions. These models successfully predicted the optimal parameter sets, with RF and XGB achieving UTS values of up to 483 MPa. The combined use of HRTEM and machine learning provides new insights into the phase evolution in AA7075 FSW joints, while reducing experimental workload and resource consumption.
Background: This study aimed to translate and cross-culturally adapt the modified Short QUestionnaire to ASsess Health-enhancing physical activity (mSQUASH) into Korean for use in patients with axial spondyloarthritis (axSpA). Methods: The mSQUASH was translated into Korean and subsequently back-translated into English by two independent translators per phase. An expert committee, comprising translators, two patients, and the research team, reviewed and refined the translation to produce a pre-final version. A field test, including cognitive debriefing interviews, was conducted with 30 patients diagnosed with axSpA. Their feedback was used to finalize the Korean version of the mSQUASH. Results: The translation process was smooth, with minor discrepancies resolved through expert consensus. Cognitive debriefing confirmed that the questionnaire items were clear, relevant, and easy to understand and complete. No essential aspects of physical activity were reported as missing. However, participants suggested modifying certain sport examples to better reflect Korean cultural practices. Conclusion: The final Korean version of the mSQUASH demonstrated both linguistic accuracy and cultural appropriateness, supporting its suitability for use in clinical practice and research involving Korean patients with axSpA.
The precise ontogeny of extrathymic T cells remains elusive, and the potential contribution of self-renewing B1 cells to T cell generation has not been defined. Here, we identify a distinct population of TCR+CD19+ double-positive (DP) cells in the peritoneal cavity that serves as a developmental intermediate between B1a cells and extrathymic T cells. These DP cells originated from CD19+ B-lineage cells and were highly enriched within the CD5+CD43+ B1a subset. Phenotypic and t-SNE analyses revealed ordered transitional states characterized by progressive acquisition of T-lineage features. In vivo adoptive transfer and in vitro co-culture assays demonstrated that B1a cells generated functional extrathymic T cells, a process promoted by Notch signaling and IL-2 family cytokines. During this process, B1a-derived cells underwent transient Rag reactivation and TCR rearrangement and acquired canonical effector functions, including cytokine production and cytotoxicity. These findings uncover B1a lineage plasticity and define an unrecognized pathway of extrathymic T lymphopoiesis.
PURPOSE:To assess financial toxicity and its predictors among South Korean family caregivers of people living with dementia (PLWD). METHOD:In the current cross-sectional survey, 230 family caregivers of PLWD were recruited from a tertiary hospital outpatient clinic and five community-based dementia care centers in South Korea. Data were collected using validated instruments. Multiple linear regression was used to identify predictors of financial toxicity. RESULTS:Among participants, 64.7% experienced moderate to severe financial toxicity (mean score of the Korean version of the Comprehensive Score for Financial Toxicity = 22.65 [SD = 8.27]). Higher caregiver burden (B = -0.35, 95% confidence interval [-0.46, -0.24]), female sex, younger age, and poor self-rated health were statistically significant predictors. CONCLUSION:Most family caregivers of PLWD in South Korea experience considerable financial toxicity, strongly associated with caregiving burden. Findings highlight the need for tailored psychological and financial interventions, and policy support for high-risk family caregivers of PLWD.
