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.

Reference Standard of Median Nerve Conduction Study in Korea.

OBJECTIVE: To establish the reference standard of the median nerve conduction study (NCS) in Korea. METHODS: A total of 648 median motor and 602 median sensory NCSs from 349 Korean healthy volunteers were tested and analyzed prospectively. Equipment calibration, assessment of intraand inter-rater reliability, and the NCSs per se were conducted according to a predetermined protocol. A reference standard was established from uncertainty components for the following parameters: the onset and peak latencies; the baseline-to-peak and peak-to-peak amplitudes; the area and duration of the negative wave; and the nerve conduction velocity. The effects of sex, age and stimulation intensity were analyzed. RESULTS: Each measured value of 648 median motor and 602 median sensory nerves were obtained and presented with both mean and expanded uncertainties, as well as mean and standard deviations. The cut-off values with expanded uncertainty were determined for different age and sex groups. After adjusting for anthropometric covariates, all parameters except duration were affected by age, and sex appeared to influence both duration and area. While stimulation intensity significantly affected some parameters including latencies, the effect sizes were negligible. CONCLUSION: We propose the median NCS reference standard using the largest Korean dataset ever available. The use of the traceable and reliable reference standard is anticipated to promote more accurate and dependable diagnosis and appropriate management of median neuropathies in Korea.

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.

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.

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.

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.

Proteomic discovery of prognostic protein biomarkers for persisting problems after mild traumatic brain injury.

Some individuals with mild traumatic brain injury (mTBI), also known as concussion, have neuropsychiatric and physical problems that last longer than a few months. Symptoms following mTBI are not only impacted by the kind and severity of the injury but also by the post-injury experience and the individual's responses to it, making the persistence of mTBI particularly difficult to predict. We aimed to identify prognostic blood-based protein biomarkers predicting 6-month outcomes, in light of the clinical course after the injury, in a longitudinal mTBI cohort (N = 42). Among 420 target proteins quantified by multiple-reaction monitoring-mass spectrometry assays of blood samples, 31, 43, and 15 proteins were significantly associated with the poor recovery of neuropsychological symptoms at < 72 h, 1 week, and 1 month after the injury, respectively. Sequential associations among clinical assessments (depressive symptoms and cognitive function) affecting the 6-month outcomes were evaluated. Then, candidate biomarker proteins indirectly affecting the outcome via neuropsychological symptoms were identified. Using the identified proteins, prognostic models that can predict the 6-month outcome of mTBI were developed. These protein biomarkers established in the context of the clinical course of mTBI may have potential for clinical application.

Risk of Ischemic Heart Disease in Chronic Obstructive Pulmonary Disease: A Nationwide Cohort Study.

BACKGROUND: Subjects with chronic obstructive pulmonary disease (COPD) have a higher risk of ischemic heart disease (IHD) than individuals without COPD; however, longitudinal evidence is lacking. Therefore, we aimed to estimate the risk of IHD between COPD and control cohorts using a longitudinal nationwide database. METHODS: We used 2009-2017 data from the Korean National Health Insurance Service National Sample Cohort (NHIS-NSC). Adult participants at least 20 years of age who underwent health examinations and without a history of COPD or IHD were included (n = 540,976). Participants were followed from January 1, 2009, until death, development of IHD, or December 31, 2019, whichever came first. RESULTS: At baseline, there were 3,421 participants with incident COPD and 537,555 participants without COPD. During a median of 8.0 years (5.3-9.1 years) of follow-up, 2.51% of the participants with COPD (n = 86) and 0.77% of the participants without COPD (n = 4,128) developed IHD, with an incidence of 52.24 and 10.91 per 10,000 person-years, respectively. Participants with COPD had a higher risk of IHD (adjusted hazard ratio, 1.55; 95% confidence interval, 1.25-1.93) than subjects without COPD. Demographics such as age, sex, body mass index, and personal health behaviors including smoking status and physical activity did not show significant interaction with the relationship between COPD and IHD (P for interaction > 0.05 for all). CONCLUSION: The results indicate that COPD is associated with the development of IHD independent of demographic characteristics and health-related behaviors. Based on these results, clinicians should closely monitor the onset of IHD in subjects with COPD.

Clinical Practice Guideline for Stroke Rehabilitation in Korea-Part 1: Rehabilitation for Motor Function (2022).

This clinical practice guideline (CPG) is the fourth edition of the Korean guideline for stroke rehabilitation, which was last updated in 2016. The development approach has been changed from a consensus-based approach to an evidence-based approach using the Grading of Recommendations Assessment Development and Evaluation (GRADE) method. This change ensures that the guidelines are based on the latest and strongest evidence available. The aim is to provide the most accurate and effective guidance to stroke rehabilitation teams, and to improve the outcomes for stroke patients in Korea. Fifty-five specialists in stroke rehabilitation and one CPG development methodology expert participated in this development. The scope of the previous clinical guidelines was very extensive, making it difficult to revise at once. Therefore, it was decided that the scope of this revised CPG would be limited to Part 1: Rehabilitation for Motor Function. The key questions were selected by considering the preferences of the target population and referring to foreign guidelines for stroke rehabilitation, and the recommendations were completed through systematic literature review and the GRADE method. The draft recommendations, which were agreed upon through an official consensus process, were refined after evaluation by a public hearing and external expert evaluation.

Clinical Practice Guidelines for Oropharyngeal Dysphagia.

OBJECTIVE: Dysphagia is a common clinical condition characterized by difficulty in swallowing. It is sub-classified into oropharyngeal dysphagia, which refers to problems in the mouth and pharynx, and esophageal dysphagia, which refers to problems in the esophageal body and esophagogastric junction. Dysphagia can have a significant negative impact one's physical health and quality of life as its severity increases. Therefore, proper assessment and management of dysphagia are critical for improving swallowing function and preventing complications. Thus a guideline was developed to provide evidence-based recommendations for assessment and management in patients with dysphagia. METHODS: Nineteen key questions on dysphagia were developed. These questions dealt with various aspects of problems related to dysphagia, including assessment, management, and complications. A literature search for relevant articles was conducted using Pubmed, Embase, the Cochrane Library, and one domestic database of KoreaMed, until April 2021. The level of evidence and recommendation grade were established according to the Grading of Recommendation Assessment, Development and Evaluation methodology. RESULTS: Early screening and assessment of videofluoroscopic swallowing were recommended for assessing the presence of dysphagia. Therapeutic methods, such as tongue and pharyngeal muscle strengthening exercises and neuromuscular electrical stimulation with swallowing therapy, were effective in improving swallowing function and quality of life in patients with dysphagia. Nutritional intervention and an oral care program were also recommended. CONCLUSION: This guideline presents recommendations for the assessment and management of patients with oropharyngeal dysphagia, including rehabilitative strategies.

Trends in Frailty Prevalence Among Older Adults in Korea: A Nationwide Study From 2008 to 2020.

BACKGROUND: We aimed to evaluate the nationwide trend of the prevalence of frailty in older adults in Korea from 2008 to 2020 to inform future geriatric healthcare policies. METHODS: The study used data of individuals aged 65 years and older from the Korea National Health and Nutrition Examination Survey, a nationwide repeated cross-sectional survey. Frailty was defined using frailty index, classified as non-frail (frailty index ≤ 0.15), pre-frail (0.15 < frailty index ≤ 0.25), or frail (frailty index > 0.25). RESULTS: The study included 17,784 individuals, with the mean age of 72.4 and mean frailty index of 0.2. The prevalence of frailty in older adults in South Korea decreased significantly from 2008 (41.1%) to 2020 (23.1%). The decrease in the frailty index was observed in all age groups (all P < 0.05). As components of frailty index, we found that certain comorbidities, such as dyslipidemia, diabetes mellitus, and cardiovascular disease, have increased over time, while factors such as chewing difficulty, activity limitation, and smoking, have decreased. CONCLUSION: The prevalence of frailty in older adults in South Korea has decreased significantly during the study period. Historical improvements in healthcare access and preventive measures may have contributed to this trend.

The Clinical Frailty Scale as a Risk Assessment Tool for Dysphagia in Older Inpatients: A Cross-Sectional Study.

BACKGROUND: Dysphagia is a common problem with potentially serious consequences including malnutrition, dehydration, pneumonia, and death. However, there are challenges in screening for dysphagia in older adults. We assessed the feasibility of using the Clinical Frailty Scale (CFS) as a risk assessment tool for dysphagia. METHODS: This cross-sectional study was conducted at a tertiary teaching hospital from November 2021 to May 2022 and included 131 older patients (age ≥65 years) admitted to acute wards. We used the Eating Assessment Tool-10 (EAT-10), which is a simple measure for identifying individuals at risk of dysphagia, to assess the relationship between EAT-10 score and frailty status as measured using the CFS. RESULTS: The mean age of the participants was 74.3±6.7 years, and 44.3% were male. Twenty-nine (22.1%) participants had an EAT-10 score ≥3. The CFS was significantly associated with an EAT-10 score ≥3 after adjusting for age and sex (odds ratio=1.48; 95% confidence interval [CI], 1.09-2.02). The CFS was able to classify the presence of an EAT-10 score ≥3 (area under the receiver operating characteristic [ROC] curve=0.650; 95% CI, 0. 544-0.756). The cutoff point for predicting an EAT-10 score ≥3 was a CFS of 5 according to the highest Youden index, with a sensitivity of 82.8% and a specificity of 46.1%. The positive and negative predictive values were 30.4% and 90.4%, respectively. CONCLUSION: The CFS can be used as a tool to screen for the risk of swallowing difficulty in older inpatients to determine clinical management encompassing drug administration routes, nutritional support, prevention of dehydration, and further evaluation of dysphagia.

Long-Range Orbital Torque by Momentum-Space Hotspots.

While it is often assumed that the orbital response is suppressed and short ranged due to strong crystal field potential and orbital quenching, we show that the orbital response can be remarkably long ranged in ferromagnets. In a bilayer consisting of a nonmagnet and a ferromagnet, spin injection from the interface results in spin accumulation and torque in the ferromagnet, which rapidly oscillate and decay by spin dephasing. In contrast, even when an external electric field is applied only on the nonmagnet, we find substantially long-ranged induced orbital angular momentum in the ferromagnet, which can go far beyond the spin dephasing length. This unusual feature is attributed to nearly degenerate orbital characters imposed by the crystal symmetry, which form hotspots for the intrinsic orbital response. Because only the states near the hotspots contribute dominantly, the induced orbital angular momentum does not exhibit destructive interference among states with different momentum as in the case of the spin dephasing. This gives rise to a distinct type of orbital torque on the magnetization, increasing with the thickness of the ferromagnet. Such behavior may serve as critical long-sought evidence of orbital transport to be directly tested in experiments. Our findings open the possibility of using long-range orbital response in orbitronic device applications.

Enhanced spin Seebeck effect via oxygen manipulation.

Spin Seebeck effect (SSE) refers to the generation of an electric voltage transverse to a temperature gradient via a magnon current. SSE offers the potential for efficient thermoelectric devices because the transverse geometry of SSE enables to utilize waste heat from a large-area source by greatly simplifying the device structure. However, SSE suffers from a low thermoelectric conversion efficiency that must be improved for widespread application. Here we show that the SSE substantially enhances by oxidizing a ferromagnet in normal metal/ferromagnet/oxide structures. In W/CoFeB/AlOx structures, voltage-induced interfacial oxidation of CoFeB modifies the SSE, resulting in the enhancement of thermoelectric signal by an order of magnitude. We describe a mechanism for the enhancement that results from a reduced exchange interaction of the oxidized region of ferromagnet, which in turn increases a temperature difference between magnons in the ferromagnet and electrons in the normal metal and/or a gradient of magnon chemical potential in the ferromagnet. Our result will invigorate research for thermoelectric conversion by suggesting a promising way of improving the SSE efficiency.

First report of Stagonosporopsis cucumeris causing internal fruit rot on Oriental melon (Cucumis melo L.) in Korea.

Oriental melon (Cucumis melo L.) is a popular Korean, Japanese, and Chinese fruit (Shin et al. 2017). In April 2022, abnormal fruit (n=20) that were collected in Sangju in Gyeongbuk Province (36°27'54.6"N, 128°10'49.7"E), Korea showed approximately 5% disease incidence with severity of 10-15%. Initial symptoms included shriveling, soaking, softening, dark discoloration, and sunken lesions. Internally, a rot extended to flesh, darkening from brown to black, and producing black mycelial masses. Two fungal strains (OM-rot-01 and OM-rot-02) were isolated and exhibited similar culture characteristics: aerial mycelium that was flat and pale grey to olivaceous on potato dextrose (PDA), malt extract (MEA), and oatmeal agar (OA) after seven days at 25°C and produced abundant buff-colored pycnidial ascomata on OA. Asci were bitunicate, clavate to cylindrical, 48.4 to 69.0 × 6.1 to 6.9 µm (n=10), and ascospores were biseriate, sparse, ellipsoidal, straight to slightly curved, hyaline, smooth, apex obtuse, 1-septate, 11.1 to 14.9 × 3.8 to 5.4 µm (n=20). Conidiomata were pycnidial, mostly solitary, irregular, pale brown to black, semi-immersed, 150 to 220 × 120 to 200 µm. Conidia were oblong or ovoid, smooth, thin-walled, hyaline, aseptate, 4.4 to 6.7 × 2.0 to 2.8 µm (n=35), with 1-3 guttules per conidium. The morphological characteristics corresponded to those of Stagonosporopsis cucumeris (Hou et al. 2020). For molecular identification, genomic DNA was extracted from strains (OM-rot-01 and OM-rot-02), and the ITS regions, partial 28S rDNA (LSU), beta-tubulin (TUB2), and RNA polymerase II second largest subunit (RPB2) genes were amplified and sequenced (White et al. 1990; Woudenberg et al. 2009; Vilgalys & Hester 1990; Liu et al. 1999). The obtained sequences revealed 99-100% homology with S. cucumeris accessions (MH858625, MH870265, MT005554, and MT018021). The sequences were deposited in GenBank with accession nos. for ITS regions (OP788058, OP788059), 28S rDNA (OP788094, OP788095), TUB2 (OP810568, OP810569), and RPB2 (OP810570, OP810571). Phylogenetic analysis combined with ITS, LSU, TUB2, and RPB2 concatenated sequences using neighbor-joining method revealed that the strains were S. cucumeris. To confirm pathogenicity, OM-rot-01 was inoculated onto ripe, asymptomatic Oriental melon fruit (n=6). After they were surface sterilized with 70% alcohol, fruit were wounded using a sterilized needle and corkborer, and 5-mm-diameter mycelial plugs were attached to the wound sites, followed by covering of the fruit with aluminum foil and maintenance in a plastic box (>90% relative humidity) at 25°C. Non-wounded fruit were inoculated and incubated in a similar manner, and fruit that were inoculated with PDA plugs served as controls (n=3). The aluminum foil was removed after three days of inoculation, and other conditions were kept constant. After six days, typical internal fruit rot symptoms were observed in both wounded and non-wounded fruit; brown to black rot extended into flesh, whereas control fruit remained asymptomatic. Fungi reisolated from lesions were morphologically identical to OM-rot-01; identity was confirmed by molecular analysis, fulfilling Koch's postulates, and the pathogenicity test was conducted three times. S. cucumeris was found as a canker on Cucumis sativus in the Netherlands (Hou et al. 2020), but has not been reported elsewhere as a pathogen on Cucumis spp. To our knowledge, this is the first report of S. cucumeris causing internal fruit rot on Oriental melon in Korea. This disease poses a threat to melon production, so accurate identification of the pathogen is a key starting point for development of sustainable management practices.

Bidirectional association between Parkinson's disease and obstructive sleep apnea: a cohort study.

STUDY OBJECTIVES: Chronic intermittent hypoxia due to obstructive sleep apnea (OSA) causes oxidative stress, which may contribute to the pathophysiology of Parkinson's disease (PD). However, the bidirectional relationship between PD and OSA has not been satisfactorily established. The objective of this study was to try to estimate whether there is a bidirectional relationship between PD and OSA through a retrospective cohort study in the South Korean population. METHODS: This study used data from the Korean National Health Information Database of the National Health Insurance Service, which contains data from 3.5 million individuals evenly distributed. In study 1, patients with OSA were matched in a 1:2 ratio with non-OSA controls. In study 2, patients with PD were matched in a 1:2 ratio with non-PD controls. A stratified Cox proportional hazards model was used to calculate hazard ratios. RESULTS: In study 1, which included 6,396 patients with OSA and 12,792 non-OSA controls, the incidence of PD per 10,000 person-years was 11.59 in the OSA group and 8.46 in the non-OSA group. The OSA group demonstrated a 1.54-fold higher incidence of PD than the non-OSA group (95% confidence interval, 1.14-2.07; P < .05). In study 2, which included 3,427 patients with PD and 6,854 non-PD controls, the incidence of OSA per 10,000 person-years was 14.97 in the PD group and 7.72 in the non-PD group. The PD group demonstrated a 1.92-fold higher incidence of OSA than the non-PD group (95% confidence interval, 1.32-2.78; P < .05). CONCLUSIONS: This study supports a possible bidirectional relationship between PD and OSA. CITATION: Jeon S-H, Hwang YS, Oh S-Y, et al. Bidirectional association between Parkinson's disease and obstructive sleep apnea: a cohort study. J Clin Sleep Med. 2023;19(9):1615-1623.

Deciphering Functional Connectivity Differences Between Motor Imagery and Execution of Target-Oriented Grasping.

This study aimed to delineate overlapping and distinctive functional connectivity in visual motor imagery, kinesthetic motor imagery, and motor execution of target-oriented grasping action of the right hand. Functional magnetic resonance imaging data were obtained from 18 right-handed healthy individuals during each condition. Seed-based connectivity and multi-voxel pattern analyses were employed after selecting seed regions with the left primary motor cortex and supplementary motor area. There was equivalent seed-based connectivity during the three conditions in the bilateral frontoparietal and temporal areas. When the seed region was the left primary motor cortex, increased connectivity was observed in the left cuneus and superior frontal area during visual and kinesthetic motor imageries, respectively, compared with that during motor execution. Multi-voxel pattern analyses revealed that each condition was differentiated by spatially distributed connectivity patterns of the left primary motor cortex within the right cerebellum VI, cerebellum crus II, and left lingual area. When the seed region was the left supplementary motor area, the connectivity patterns within the right putamen, thalamus, cerebellar areas IV-V, and left superior parietal lobule were significantly classified above chance level across the three conditions. The present findings improve our understanding of the spatial representation of functional connectivity and its specific patterns among motor imagery and motor execution. The strength and fine-grained connectivity patterns of the brain areas can discriminate between motor imagery and motor execution.