Publications by authors named "Ryuk-Jun Kwon"

Visfatin, an adipokine secreted by various cell types, plays multifaceted pathophysiological roles in inflammatory conditions, including obesity, which is closely associated with osteoclastogenesis, a key process underlying bone loss and increased osteoporosis (OP) risk. However, the role of visfatin in osteoclastogenesis remains controversial. This study was conducted to investigate the effects of visfatin on receptor activator of nuclear factor kappa-B ligand (RANKL)-induced osteoclast differentiation from precursor cells in vitro.

View Article and Find Full Text PDF

Microglia play a crucial role as immune cells responsible for the brain's defense mechanisms. Similar to the actions of macrophages in the body, microglial cells elicit an inflammatory immune response in the brain. Recent papers highlight activated microglial cells as pivotal contributors to inflammatory responses in the brain, leading to damage to nerve tissue and the onset of Alzheimer's disease (AD).

View Article and Find Full Text PDF
Article Synopsis
  • Renal cell carcinoma (RCC) is a severe kidney cancer with a poor prognosis, and the role of Niemann-Pick C1-Like 1 (NPC1L1) in its progression is not well understood.
  • In this study, researchers compared NPC1L1 expression in normal versus RCC tissues and found that lower levels in RCC, especially in certain subtypes, were linked to worse patient survival.
  • The findings indicate that higher NPC1L1 levels could be a potential independent prognostic marker for bad outcomes in RCC, necessitating further research on its mechanisms in cancer progression.
View Article and Find Full Text PDF

: This study aimed to investigate the association between insulin resistance, as measured by the triglyceride-glucose index (TyG index), and hearing impairment in middle-aged women in Korea. : This cross-sectional survey utilized data from the Korea National Health and Nutrition Examination Survey (KNHANES) IV (2007-2009), specifically from the period after July 21, 2009, when hearing test results became available, and from the KNHANES V (2010-2012). This study was conducted on 5416 women aged 40 to 69 who had completed both the health examination survey and audiometric tests, excluding those with missing data on menopausal status and the use of hormone replacement therapy.

View Article and Find Full Text PDF

Microglia, essential immune cells in the brain, play crucial roles in neuroinflammation by performing various functions such as neurogenesis, synaptic pruning, and pathogen defense. These cells are activated by inflammatory factors like β-amyloid (Aβ) and oxysterols, leading to morphological and functional changes, including the secretion of inflammatory cytokines and the upregulation of MHC class II molecules. This study focused on identifying specific markers for microglial activation, with a particular emphasis on the roles of oxysterols in this process.

View Article and Find Full Text PDF

Background: Insulin resistance contributes to the development of cardiovascular disease and type 2 diabetes mellitus. Smoking leads to an increase in triglyceride levels, which, in turn, increases insulin resistance. Although the number of e-cigarette users has increased in recent years, few studies have investigated the association between ecigarette use and insulin resistance.

View Article and Find Full Text PDF

Elevated uric acid levels are linked with obesity and diabetes. Existing research mainly examines the relationship between sugar-sweetened carbonated beverage (SSB) consumption and uric acid levels. This study explored the association between the quantity and frequency of SSB consumption and elevated uric acid levels in Korean adults.

View Article and Find Full Text PDF

Background: Skipping breakfast is associated with an increased risk of chronic inflammatory diseases. This study aimed to examine the association between breakfast-eating habits and inflammation, using high-sensitivity C-reactive protein (hs-CRP) as a marker.

Methods: A total of 4,000 Korean adult males with no history of myocardial infarction, angina, stroke, diabetes, rheumatoid arthritis, cancer, or current smoking were included.

View Article and Find Full Text PDF

Background: Glioblastoma (GBM) is the most common malignant brain tumor and has poor survival. An elevated cholesterol level is involved occurrence and progression of brain tumors. Microsomal triglyceride transfer protein (MTTP) is a target for lowering lipids, and its inhibition helps to improve hyperlipidemia.

View Article and Find Full Text PDF

Objectives: To investigate differences in the incidence of enteropathy or intestinal malabsorption in patients taking angiotensin II receptor blockers (ARBs), angiotensin-converting enzyme inhibitor (ACEI), calcium channel blocker (CCB), and beta blockers (BBs) at a single center in Korea.

Methods: In this retrospective study, we utilized data from the Yangsan electronic medical records to identify 129,169 patients. These individuals were prescribed olmesartan, other ARBs, ACEI, CCB, and BBs between November 2008 and February 2021.

View Article and Find Full Text PDF
Article Synopsis
  • Sarcopenia, characterized by loss of muscle mass, strength, and low physical performance, is linked to increased cardiovascular disease risk and mortality, but its relationship with pulse pressure (PP), a measure of arterial stiffness, is not well established.
  • A study using data from the Korea National Health and Nutrition Examination Survey analyzed participants based on their PP levels and handgrip strength, finding that those with higher PP had more health issues and a greater prevalence of weak handgrip strength.
  • Results indicated that individuals with PP levels of 60 mmHg or higher had significantly higher rates of low muscle strength, suggesting that monitoring PP could help identify those at risk for sarcopenia and improve overall health outcomes.
View Article and Find Full Text PDF

Sarcopenia is characterized by a loss of muscle mass and strength and is associated with a high risk of cardiovascular events and increased mortality. Pulse pressure (PP) serves as a marker for changes in heart structure and function, as well as arterial stiffness. A high PP also increases the risk of cardiovascular disease and all-cause mortality.

View Article and Find Full Text PDF

Objective: Menarche and menopause are associated with muscle loss and strength in women. Handgrip strength (HGS) is a reliable measurement method of muscle strength. However, it is unclear whether the entire reproductive period, which encompasses both menarche and menopause, is associated with HGS in postmenopausal women.

View Article and Find Full Text PDF

: Lipid-lowering agents such as ezetimibe are recommended in uncontrolled hyperlipidemia for primary and secondary prevention of cardiovascular disease. Carotid intima-media thickness (CIMT) is a surrogate marker of atherosclerosis and a predictor of cardiovascular and cerebral events. The effects of ezetimibe on CIMT have been inconsistently reported.

View Article and Find Full Text PDF

Glucocorticoids suppress the vascular inflammation that occurs under hypercholesterolemia, as demonstrated in an animal model fed a high-cholesterol diet. However, the molecular mechanisms underlying these beneficial effects remain poorly understood. Because cholesterol is oxidized to form cholesterol oxides (oxysterols) that are capable of inducing inflammation, we investigated whether glucocorticoids affect the immune responses evoked by 7α-hydroxycholesterol (7αOHChol).

View Article and Find Full Text PDF

Purpose: For the dignity of patients nearing the end of their lives, it is essential to provide end-of-life (EoL) care in a separate, dedicated space. This study investigated the utilization of specialized rooms for dying patients within a hospice unit.

Methods: This retrospective study examined patients who died in a single hospice unit between January 1, 2017, and December 31, 2021.

View Article and Find Full Text PDF

Sarcopenia causes a variety of functional impairments and is associated with all-cause mortality, but once it occurs, it is difficult to treat and reverse. However, the prevalence of sarcopenia in healthy people has never been investigated due to the low awareness of sarcopenia in healthy people. This cross-sectional study was conducted in a single health promotion center from the January 1st 2020 to the December 31st 2021.

View Article and Find Full Text PDF

Objective: Hyperuricemia is associated with metabolic and cardiovascular diseases and mortality. Efforts to lower the risk of hyperuricemia in various ways are needed as the prevalence of these diseases increases in postmenopausal women. Studies have shown that one of these methods is associated with adequate sleep duration, which is related to a low risk of hyperuricemia.

View Article and Find Full Text PDF

Background: Sleep duration is associated with hearing loss, especially presbycusis, which is the most common type of hearing loss; however, there is limited evidence regarding this association among the Korean population. We aimed to determine the relationship between sleep duration and high-frequency hearing loss in Korean adults aged ≥40 years.

Methods: We examined 5,547 Korean adults aged ≥40 years who completed audiometric tests and questionnaires regarding sleep duration during the 2010-2012 cycle of the Korea National Health and Nutrition Examination Survey.

View Article and Find Full Text PDF

Adaptable and sensitive materials are essential for the development of advanced sensor systems such as bio and chemical sensors. Biomaterials can be used to develop multifunctional biosensor applications using genetic engineering. In particular, a plasmonic sensor system using a coupled film nanostructure with tunable gap sizes is a potential candidate in optical sensors because of its simple fabrication, stability, extensive tuning range, and sensitivity to small changes.

View Article and Find Full Text PDF

Background: The protein kinase A (PKA)/cAMP response element-binding protein (CREB) has been suggested to be related to the inhibition of the proliferation of non-small cell lung cancer (NSCLC) cells. This study aimed to investigate the efficacy of a novel diarylcyclohexanone derivative, MHY4571, in regulating the PKA-CREB pathway and to study its anti-tumor role in squamous NSCLC.

Methods: We designed MHY4571 as a novel PKA inhibitor with acceptable in silico ADME properties and tested it in vitro in lung cancer cell lines and in vivo in xenograft and orthotopic mouse models of squamous cell lung carcinoma.

View Article and Find Full Text PDF

Background: Colorectal cancer (CRC) is a malignancy of the large intestine, whose development and prognosis have been demonstrated to be associated with altered lipid metabolism. High cholesterol intake is associated with an increased risk of CRC, and elevated serum cholesterol levels are known to be correlated with risk of developing CRC. Niemann-Pick C1-Like 1 (NPC1L1), a target of ezetimibe, plays an essential role in the absorption of intestinal cholesterol.

View Article and Find Full Text PDF

Background: Predicting how long a patient with far advanced cancer has to live is a significant part of hospice and palliative care. Various prognostic models have been developed, but have not been fully compared in South Korea.

Objectives: We aimed to compare the accuracy of the Prognosis in Palliative Care Study (PiPS), Palliative Prognostic Index (PPI), Palliative Prognostic Score (PaP) and Objective Prognostic Score (OPS) for patients with far advanced cancer in a palliative care unit in South Korea.

View Article and Find Full Text PDF

Background: Many researchers have identified that adequate sleep duration is linked to the quality of life and metabolic diseases. Nowadays, it is hard to take enough sleep, so weekend catch-up sleep (CUS) may be an alternative option in modern society. To our knowledge, no previous studies reported the association between weekend CUS and metabolic syndrome, especially in the Korean population.

View Article and Find Full Text PDF

Background: This study assessed the predictive value of receptor-interacting protein kinase 3 (RIPK3) expression and its correlation with clinicopathological characteristics, disease-free survival, and overall survival of patients with cisplatin-based adjuvant chemotherapy after lung adenocarcinoma resection.

Methods: This study included 50 patients who underwent cisplatin-based adjuvant chemotherapy after lung adenocarcinoma (stage IB-IIIA) resection. Immunohistochemical analysis was performed by probing tumor tissue microarrays with anti-RIPK3 antibody.

View Article and Find Full Text PDF