Orbital Torque in Rare-Earth Transition-Metal Ferrimagnets.

Orbital currents have recently emerged as a promising tool to achieve electrical control of the magnetization in thin-film ferromagnets. Efficient orbital-to-spin conversion is required in order to torque the magnetization. Here, we show that the injection of an orbital current in a ferrimagnetic Gd_{y}Co_{100-y} alloy generates strong orbital torques whose sign and magnitude can be tuned by changing the Gd content and temperature. The effective spin-orbital Hall angle reaches up to -0.25 in a Gd_{y}Co_{100-y}/CuO_{x} bilayer compared to +0.03 in Co/CuO_{x} and +0.13 in Gd_{y}Co_{100-y}/Pt. This behavior is attributed to the local orbital-to-spin conversion taking place at the Gd sites, which is about 5 times stronger and of the opposite sign relative to Co. Furthermore, we observe a manyfold increase in the net orbital torque at low temperature, which we attribute to the improved conversion efficiency following the magnetic ordering of the Gd and Co sublattices.

Efficacy of leuprorelin in spinal and bulbar muscular atrophy: a 3-year observational study.

OBJECTIVE: This study aimed to investigate the long-term effects and functional outcomes of androgen suppression therapy using leuprorelin among Korean patients with spinal and bulbar muscular atrophy (SBMA). METHODS: This observational study enrolled patients with genetically confirmed SBMA who provided informed consent. Leuprorelin was administered via subcutaneous injection every 12 weeks. The primary outcome measure was the change in total Spinal and Bulbar Muscular Atrophy Functional Rating Scale (SBMAFRS) scores. RESULTS: A total of 48 SBMA patients were evaluated in this study. Among them, 39 patients underwent androgen suppression therapy over a 3-year period. The total SBMAFRS score decreased from 41.72 ± 5.55 to 36.74 ± 7.74 (p < 0.001) in patients who completed their treatment. The subgroup with a baseline SBMAFRS score of ≥ 42 had a significantly lower decline in SBMAFRS score than did those with a baseline SBMAFRS score of ≤ 41. We determined that at a baseline, SBMAFRS cutoff value of 41.5 could predict good prognosis, with a corresponding area under the curve of 0.689. CONCLUSION: Despite androgen suppression therapy, all enrolled participants exhibited a decrease in the overall SBMAFRS score. However, those with a baseline SBMAFRS of ≥ 42 showed a mild decrease in scores, indicating a more favorable prognosis. These findings suggest that a higher baseline motor function was a key prognostic indicator in SBMA treatment and that initiating early leuprorelin treatment in patients with high baseline function may lead to good clinical outcomes.

A link between systemic low-grade inflammation and frailty in older adults: clinical evidence from a nationwide population-based study.

Background/Aims: Despite the possible role of systemic low-grade inflammation on frailty, the majority of previous studies have focused solely on the phenotypic frailty with limited participant numbers, thereby weakening the evidence supporting the notion that circulating C-reactive protein (CRP) could be a potential frailty biomarker. Methods: This study is a nationally representative, population-based, cross-sectional analysis from the Korea National Health and Nutrition Examination Survey, involving 5,359 participants aged 65 and older. We generated a deficit accumulation frailty index (FI) based on 38 items, encompassing physical, cognitive, psychological, and social status. Frailty was classified as non-frail (FI ≤ 0.15), pre-frail (0.15 < FI ≤ 0.25), or frail (FI > 0.25). Serum high-sensitivity CRP (hsCRP) levels were measured by immunoturbidometric method. Results: After adjusting for confounders including age, sex, income, education, smoking, hypertension, diabetes, dyslipidemia, stroke, cardiovascular diseases, and body mass index, serum hsCRP levels were 29.4% higher in frail participants compared to their non-frail counterparts (p = 0.001). Additionally, circulating hsCRP concentrations positively correlated with the FI (p = 0.003), and the odds ratio for frailty per standard deviation increase in serum hsCRP was 1.18 (p = 0.001). Moreover, older adults in the highest hsCRP quartile exhibited a significant higher FI with a 1.59-fold increased odds ratio for frailty than those in the lowest quartile (p = 0.002 and 0.001, respectively). Conclusions: These findings validate the impact of age-related systemic low-grade inflammation on frailty and support the utility of serum hsCRP as a potential biomarker for detecting frailty in older adults.

Association between obstructive sleep apnea and risk of Benign vocal fold lesions: A nationwide 9-year follow-up cohort study.

Since obstructive sleep apnea (OSA) affects various parts of the body, there has been little interest about the effect of OSA on voice. The objective of this study was to evaluate the risk of benign vocal fold lesions (BVFL) in OSA patients. This study used data from the National Health Insurance Service (NHIS) database. The study group was defined as the group diagnosed with OSA between 2008 and 2011. Non-OSA groups were selected based on propensity score (PS) matching. Incidence of BVFL among participants during the follow-up was analyzed. Cox proportional hazard regression analyses were performed to evaluate the association between OSA and incident BVFL. The HR value of the OSA group calculated by considering 8 variables indicates that the risk of developing BVFL is 79% higher than that of the control group. Further, among OSA patients, patients with a history of OP had a 35% lower risk of developing BVFL. The relationships between BVFL and 7 individual variables considered were as follows: For age, HR for the 40 to 59 years group was 1.20 (95%CI, 1.09-1.32). For sex, the HR in the female group was 1.22 (95%CI, 1.10-1.35). For residential areas, the HR values for "Seoul" 1.39 (95%CI, 1.23-1.59). In the high economic status group, the HR was 1.10 (95%CI, 1.01-1.21). This observational study indicated that OSA is associated with an increased incidence of BVFL. The incidence of BVFL increased with older age, female sex, and high SES.

Increasing incidence of Parkinson's disease in patients with epilepsy: A Nationwide cohort study.

BACKGROUND: Although epilepsy is an uncommon comorbidity of Parkinson's disease (PD), the exact incidence of PD among the patients with epilepsy is not clarified yet. OBJECTIVES: We aimed to estimate the incidence of PD in patients with epilepsy and explore the association between epilepsy and PD. METHODS: Epilepsy patients enrolled in the National Health Insurance Service Health Screening Cohort (NHIS-HealS) (2002-2013) between 2003 and 2007 were set up as the experimental group. The major outcome was the occurrence of PD. Non-epilepsy patients were obtained through Propensity Score Matching of 'greedy nearest neighbor' algorithm in 1:1 ratio. The Cox Proportional Hazards model was used to calculate PD incidence and hazard ratio (HR). RESULTS: A total of 10,510 patients were finally included in the study, which contained 5255 patients in epilepsy and non-epilepsy groups, respectively. During the follow-up period, 85 patients with Parkinson's disease among 5255 patients with epilepsy and 57 patients with Parkinson's disease among 5255 patients without epilepsy occurred. The 10,000 Person-Year (PY), representing the number of PD patients per 10,000 per year, was 21.38 in the epilepsy group and 11.18 in the non-epilepsy group. When all variables were adjusted, it was found that the epilepsy group had a 2.19 times significantly higher risk of developing Parkinson's disease than the control group (The adjusted HR: 2.19 (95% CI, 1.55-3.12)). CONCLUSION: This study indicates an increased risk of PD in patients with epilepsy. However, further research is needed to prove an exact causal relationship between these two brain disorders.

Higher serum uric acid as a risk factor for frailty in older adults: A nationwide population-based study.

BACKGROUND: Uric acid (UA), the terminal breakdown product of purine metabolism, possesses contradictory roles, functioning both as an inflammatory mediator and as an antioxidant. Its clinical relevance, particularly in geriatric populations, remains a topic of ongoing debate. Aiming to elucidate whether circulating UA is detrimental or beneficial to human health, we investigate the association between serum UA concentrations and the frailty index-a comprehensive measure of biological aging in a nationally representative cohort of community-dwelling older adults. METHODS: We conducted a population-based, cross-sectional study utilizing data from the Korea National Health and Nutrition Examination Survey. The sample included 4268 participants aged 65 years and above. A deficit accumulation frailty index (FI) was constructed using 38 items that assess physical, cognitive, psychological, and social domains. Based on the FI, participants were categorized into non-frail (FI ≤ 0.15), pre-frail (0.15 < FI ≤ 0.25), or frail (FI > 0.25). Serum UA levels were quantified through a colorimetric enzymatic assay. RESULTS: After controlling for confounders such as age, sex, socioeconomic status (including income and education level), lifestyle factors (smoking status), and medical history (hypertension, diabetes, dyslipidemia, stroke, cardiovascular diseases), and body mass index, serum UA levels were observed to be significantly higher in frail participants compared with their non-frail counterparts (P < 0.001). Furthermore, serum UA concentrations demonstrated a positive correlation with the FI (P < 0.001), and the odds ratio for frailty per 1 mg/dL increase in serum UA was 1.22 (P < 0.001). Additionally, older adults in the highest quartile of UA levels exhibited a significantly higher FI and 1.66-fold increased odds of frailty compared with those in the lowest quartile (P = 0.011 and P = 0.005, respectively). CONCLUSIONS: These findings suggest that elevated circulating UA levels may act as a pro-aging factor rather than an anti-aging one in older adults, highlighting its potential role in accelerating biological aging. The data further support the utility of serum UA as a potential blood-based biomarker for frailty in this demographic, contributing to the expanding evidence on its significance in geriatric health assessments.

Ursodeoxycholic acid is associated with better clinical outcomes in COVID-19 patients: A population-based cohort study.

BACKGROUND: Several studies have investigated the relationship between ursodeoxycholic acid (UDCA) and coronavirus disease 2019 (COVID-19). However, complex and conflicting results have generated confusion in the application of these results. OBJECTIVE: We aimed to investigate whether the association between UDCA and COVID can also be demonstrated through the analysis of a large-scale cohort. METHODS: This retrospective study used local and nationwide cohorts, namely the Jeonbuk common data model cohort (JBUH CDM) and the Korean National Health Insurance claim-based database (NHIS). We investigated UDCA intake and its relationship with COVID-19 susceptibility and severity using validated propensity score (PS) matching. RESULTS: Regarding the COVID-19 susceptibility, the adjusted hazard ratio (aHR) value of the UDCA intake was significantly lowered to 0.71 in the case of JBUH CDM (95% confidence interval (CI): 0.52-0.98), and was significantly lowered to 0.93 (95% CI: 0.90-0.96) in the NHIS. Regarding the COVID-19 severity, the UDCA intake was found to be significantly lowered to 0.21 (95% CI: 0.09-0.46) in the case of JBUH CDM. It was also found that the aHR value was significantly lowered to 0.77 in the case of the NHIS (95% CI: 0.62-0.95). CONCLUSIONS: Using a large-scale local and nationwide cohort, we confirmed that UDCA intake was significantly associated with the reduction of COVID-19 susceptibility and severity. These trends remained consistent regardless of the UDCA dosage. This suggests the potential of UDCA as a preventive and therapeutic agent for COVID-19.