Metabolic syndrome, a constellation of cardiovascular disease risk factors, is a global pandemic. Over 30% of the adult population in both South Korea and the United States are currently classified as having metabolic syndrome. Vascular endothelial function is a precursor of future atherosclerotic cardiovascular disease. Conduit artery flow-mediated dilation using ultrasonography is considered the non-invasive, gold standard for assessing nitric oxide-mediated vascular endothelial function. Patients with metabolic syndrome commonly exhibit increased insulin resistance and hyperglycemia, which are thought to impair vascular endothelial function by increasing oxidative stress and reducing nitric oxide bioavailability in the vascular endothelium and in smooth muscle cells. Previous findings have indicated that long-term aerobic exercise has a positive effect on impaired vascular endothelial function in metabolic syndrome patients, but the underlying mechanisms have not been fully elucidated. Therefore, further studies are needed that will apply different exercise modalities and intensities with the goal of improving vascular endothelial function in patients with metabolic syndrome, as well as investigation of the associated mechanisms. Ultimately, well-designed future studies will help to establish and develop exercise prescription and/or exercise therapy programs that can reduce cardiovascular disease risk and improve cardiovascular health in metabolic syndrome patients.
Adult ; Arteries ; Biological Availability ; Cardiovascular Diseases ; Endothelium, Vascular ; Exercise ; Exercise Therapy ; Humans ; Hyperglycemia ; Insulin Resistance ; Korea ; Myocytes, Smooth Muscle ; Nitric Oxide ; Oxidative Stress ; Pandemics ; Prescriptions ; Risk Factors ; Ultrasonography ; United States

OBJECTIVES: The aim of this study was to compare the osteogenic effects of demineralized dentin matrix (DDM) combined with recombinant human bone morphogenetic protein-2 (rhBMP-2) in rabbit calvarial defects with DDM and anorganic bovine bone (ABB) combined with rhBMP-2. MATERIALS AND METHODS: Four round defects with 8-mm diameters were created in each rabbit calvaria. Each defect was treated with one of the following: 1) DDM, 2) ABB/rhBMP-2, or 3) DDM/rhBMP-2. The rhBMP-2 was combined with DDM and ABB according to a stepwise dry and dip lyophilizing protocol. Histological and microcomputed tomography (µCT) analyses were performed to measure the amount of bone formation and bone volume after 2- and 8-week healing intervals. RESULTS: Upon histological observation at two weeks, the DDM and ABB/rhBMP-2 groups showed osteoconductive bone formation, while the DDM/rhBMP-2 group showed osteoconductive and osteoinductive bone formation. New bone formation was higher in DDM/rhBMP-2, DDM and ABB decreasing order. The amounts of bone formation were very similar at two weeks; however, at eight weeks, the DDM/rhBMP-2 group showed a two-fold greater amount of bone formation compared to the DDM and ABB/rhBMP-2 groups. The µCT analysis showed markedly increased bone volume in the DDM/rhBMP-2 group at eight weeks compared with that of the DDM group. Notably, there was a slight decrease in bone volume in the ABB/rhBMP-2 group at eight weeks. There were no significant differences among the DDM, ABB/rhBMP-2, and DDM/rhBMP-2 groups at two or eight weeks. CONCLUSION: Within the limitations of this study, DDM appears to be a suitable carrier for rhBMP-2 in orthotopic sites.
Dentin* ; Humans* ; Osteogenesis ; Skull ; X-Ray Microtomography

Background: Aging leads to sarcopenia, which is characterized by reduced muscle mass and strength. Many factors, including altered muscle protein turnover, diminished neuromuscular function, hormonal changes, systemic inflammation, and the structure and composition of muscle fibers, play a crucial role in age-related muscle decline. This study explored differences in muscle fiber types contributing to overall muscle function decline in aging, focusing on individuals with hip fractures from falls. Methods: A pilot study at Chungnam National University Hospital collected muscle biopsies from hip fracture patients aged 20 to 80 undergoing surgical treatment. Muscle biopsies from the vastus lateralis and gluteus maximus were obtained during hip arthroplasty or internal fixation. Handgrip strength, calf and thigh circumference, and bone mineral density were evaluated in individuals with hip fractures from falls. We analyzed the relationships between each clinical characteristic and muscle fiber type. Results: In total, 26 participants (mean age 67.9 years, 69.2% male) were included in this study. The prevalence of sarcopenia was 53.8%, and that of femoral and lumbar osteoporosis was 19.2% and 11.5%, respectively. Vastus lateralis analysis revealed an age-related decrease in type IIx fibers, a higher proportion of type IIa fibers in women, and an association between handgrip strength and type IIx fibers in men. The gluteus maximus showed no significant correlations with clinical parameters. Conclusion This study identified complex associations between age, sex, handgrip strength, and muscle fiber composition in hip fracture patients, offering insights crucial for targeted interventions combating age-related muscle decline and improving musculoskeletal health.