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Aminoacyl-tRNA synthetases (ARSs) have evolved to acquire various additional domains. These domains allow ARSs to communicate with other cellular proteins in order to promote non-translational functions. Vertebrate cytoplasmic isoleucyl-tRNA synthetases (IARS1s) have an uncharacterized unique domain, UNE-I. Here, we present the crystal structure of the chicken IARS1 UNE-I complexed with glutamyl-tRNA synthetase 1 (EARS1). UNE-I consists of tandem ubiquitin regulatory X (UBX) domains that interact with a distinct hairpin loop on EARS1 and protect its neighboring proteins in the multi-synthetase complex from degradation. Phosphomimetic mutation of the two serine residues in the hairpin loop releases IARS1 from the complex. IARS1 interacts with BRCA1 in the nucleus, regulates its stability by inhibiting ubiquitylation via the UBX domains, and controls DNA repair function.

Objective: This study aimed to design and develop a virtual patient program using generative Artificial Intelligence (AI) technology, providing medical students opportunities to practice history-taking with a chatbot. We evaluated the feasibility of this approach by analyzing the quality of responses generated by the chatbot. Results: Five expert reviewers participated in a pilot test, interacting with the chatbot to take the history of a patient presenting with a urinary problem using the Korean AI platform Naver HyperCLOVA X®. They evaluated the AI responses using a five-item questionnaire rated on a five-point Likert scale. The chatbot generated 96 pairs of questions and answers, totaling 1,325 words in 177 sentences. Discourse analysis of the scripts revealed that 2.6% (34) of the words generated by the chatbot were deemed implausible and were categorized into inarticulate answers, hallucinations, and missing important information. Participants rated the AI answers as relevant (M = 4.50 ± 0.32), valid (M = 4.20 ± 0.40), accurate (M = 4.10 ± 0.20), and succinct (M = 3.80 ± 0.51), but were neutral about their fluency (M = 3.20 ± 0.60). Using generative AI for history-taking of virtual patients is feasible, but improvements are needed for more articulate and natural responses. [ABSTRACT FROM AUTHOR]

Introduction: Sarcopenia, characterized by reduced skeletal muscle mass (RMM), is increasingly recognized as a significant factor influencing outcomes in various health conditions, including stroke. Although most studies focus on sarcopenia developing during stroke rehabilitation, the impact of sarcopenia present at the onset of acute ischemic stroke remains underexplored. This study aims to evaluate the effect of RMM at stroke onset on 3-month functional outcomes in acute ischemic stroke patients. Materials and methods: We prospectively enrolled acute ischemic stroke patients admitted between May 2019 and December 2019. Muscle mass was accessed early during hospitalization using whole-body dual-energy X-ray absorptiometry (DXA), and patients were categorized into RMM and normal muscle mass (NMM) groups based on the Asian Working Group for Sarcopenia (AWGS) criteria. Functional outcomes at 3 months were assessed using the modified Rankin Scale (mRS), with unfavorable outcomes defined as mRS scores 2–5. Multivariable logistic regression and SHAP (Shapley Additive exPlanations) analyses were used to evaluate the independent impact of RMM on 3-months functional outcomes. Results: A total of 99 patients were analyzed. The RMM group had a significantly higher prevalence of unfavorable outcomes at 3 months compared to the NMM group (p < 0.001). Patients with RMM were older and presented with more severe strokes. Multivariable analysis confirmed RMM as an independent predictor of unfavorable outcomes (adjusted OR: 8.07, 95% CI: 1.603–40.66, p = 0.011), even after adjusting for age and initial stroke severity. SHAP analysis ranked RMM as the second most influential predictor of unfavorable outcomes, following NIHSS on admission. These findings indicate that RMM not only worsens initial stroke severity but also independently hinders post-stroke recovery. Conclusions: Reduced muscle mass at the onset of acute ischemic stroke is a significant, independent predictor of unfavorable outcomes at 3 months. In addition to its impact on recovery, RMM is linked to older age and more severe strokes, worsening prognosis. Maintaining muscle mass is also crucial for stroke prevention, as it supports cardiovascular health and resilience. Early identification and intervention for sarcopenia can improve recovery and reduce future stroke risk. [ABSTRACT FROM AUTHOR]

Arising from the increasing demand for electric vehicles (EVs), Ni‐rich LiNixCoyMnzO2 (NCM, x + y + z = 1, x ≥ 0.8) cathode with greatly increased energy density are being researched and commercialized for lithium‐ion batteries (LIBs). However, parasitic crack formation during the discharge–charge cycling process remains as a major degradation mechanism. Cracking leads to increase in the specific surface area, loss of electrical contact between the primary particles, and facilitates liquid electrolyte infiltration into the cathode active material, accelerating capacity fading and decrease in lifetime. In contrast, Ni‐rich NCM when used as a single crystal exhibits superior cycling performances due to its rigid mechanical property that resists cracking during long charge–discharge process even under harsh conditions. In this paper, we present comparative investigation between single crystal Ni‐rich LiNi0.92Co0.04Mn0.04O2 (SC) and polycrystalline Ni‐rich LiNi0.92Co0.04Mn0.04O2 (PC). The relatively improved cycling performances of SC are attributed to smaller anisotropic volume change, higher reversibility of phase transition, and resistance to crack formation. The superior properties of SC are demonstrated by in situ characterization and battery tests. Consequently, it is inferred from the results obtained that optimization of preparation conditions can be regarded as a key approach to obtain well crystallized and superior electrochemical performances. [ABSTRACT FROM AUTHOR]