Mira Cho

Serum ferritin level is positively associated with insulin resistance and metabolic syndrome in postmenopausal women: A nationwide population-based study

OBJECTIVE Serum ferritin, a marker of iron metabolism, has recently emerged as a biomarker of chronic low-grade inflammation. After menopause, there is a remarkable increase in insulin resistance (IR) and metabolic syndrome (MetS), which is increasingly being viewed as an inflammatory disease. Thus, we examined the associations of serum ferritin with insulin resistance and MetS in postmenopausal women. METHODS A nationwide cross-sectional study was conducted to examine the relationship between serum ferritin and IR and MetS in 2734 postmenopausal women using data from the 2010-2012 Korean National Health and Nutrition Examination Survey. The odds ratios (ORs) and 95% confidence intervals (CIs) for insulin resistance (HOMA-IR≥75th percentile, 3.04) and MetS were calculated using multiple logistic regression analyses across serum ferritin quartiles (Q1,≤36.25; Q2, 36.56-56.56; Q3, 56.57-85.98; and Q4≥85.99ng/ml). RESULTS The mean values of most cardiometabolic variables tended to increase proportionally with serum ferritin quartiles. The proportion of women with IR and MetS significantly increased in accordance with serum ferritin quartiles. Compared to individuals in the lowest quartile, the ORs (95% CIs) in the highest quartile were 2.06 (1.23-3.45) for IR and 1.92 (1.44-2.55) for MetS after adjusting for age, cigarette smoking, alcohol intake, and regular exercise. CONCLUSION Serum ferritin levels were positively and independently associated with IR and MetS in postmenopausal women. These findings suggest that serum ferritin level in postmenopausal women may help to identify the presence of IR and MetS.

Salt-Induced Electrospun Patterned Bundled Fibers for Spatially Regulating Cellular Responses

Implementing patterned fibrous matrices can offer a highly valuable platform for spatially orchestrating hierarchical cellular constructs, specifically for neural engineering approaches, in which striated alignment or directional growth of axons are key elements for the functional recovery of damaged nervous systems. Thus, understanding the structural parameters of patterned fibrous matrices that can effectively promote neural growth can provide crucial clues for designing state-of-the-art tissue engineering scaffolds. To this end, salt-induced electrospun patterned fiber bundles (SiEP bundles) comprising longitudinally stacked multiple fibers were fabricated, and their capabilities of spatially stimulating the responses of neural cells, including PC12 cells, human neural stem cells (hNSCs), and dorsal root ganglia (DRG), were assessed by comparing them to conventional fibrous matrices having either randomly oriented fibers or individually aligned fibers. The SiEP bundles possessed remarkably distinctive morphological and topographical characteristics: multicomplexed infrastructures with nano- and microscale fibers, rough surfaces, and soft mechanical properties. Importantly, the SiEP bundles resulted in spatial cellular elongations corresponding to the fiber directions and induced highly robust neurite extensions along the patterned fibers. Furthermore, the residence of hNSCs on the topographically rough grooves of the SiEP bundles boosted neuronal differentiation. These findings can provide crucial insights for designing fibrous platforms that can spatially regulate cellular responses and potentially offer powerful strategies for a neural growth system in which directional cellular responses are critical for the functional recovery of damaged neural tissues.

Targeting protein and peptide therapeutics to the heart via tannic acid modification

Systemic injection into blood vessels is the most common method of drug administration. However, targeting drugs to the heart is challenging, owing to its dynamic mechanical motions and large cardiac output. Here, we show that the modification of protein and peptide therapeutics with tannic acid—a flavonoid found in plants that adheres to extracellular matrices, elastins and collagens—improves their ability to specifically target heart tissue. Tannic-acid-modified (TANNylated) proteins do not adsorb on endothelial glycocalyx layers in blood vessels, yet they penetrate the endothelium to thermodynamically bind to myocardium extracellular matrix before being internalized by myoblasts. In a rat model of myocardial ischaemia-reperfusion injury, TANNylated basic fibroblast growth factor significantly reduced infarct size and increased cardiac function. TANNylation of systemically injected therapeutic proteins, peptides or viruses may enhance the treatment of heart diseases.The modification of protein and peptide therapeutics with tannic acid improves their ability to specifically target heart tissue, as shown with a rat model of myocardial ischaemia-reperfusion injury.

Relationship Between Handgrip Strength and Pulmonary Function in Apparently Healthy Older Women: Handgrip strength and pulmonary function

To investigate the relationship between handgrip strength and pulmonary function.

BiFACIAL (Biomimetic Freestanding Anisotropic Catechol-Interfaces with Asymmetrically Layered) Films as Versatile Extracellular Matrix Substitutes

Biological naïve extracellular matrices (ECMs) exhibit anisotropic functions in their physical, chemical, and morphological properties. Representative examples include anisotropic skin layers or blood vessels simultaneously facing multiphasic environments. Here, anisotropically multifunctional structures called BiFACIAL ( biomimetic freestanding anisotropic catechol- interfaces with asymmetrically layered) films were developed simply by contacting two polysaccharide solutions of heparin-catechol (Hep-C) and chitosan-catechol (Chi-C). Such anisotropic characters were due to controlling catechol cross-linking by alkaline pH, resulting in a trimodular structure: a rigid yet porous Hep-C exterior, nonporous interfacial zone, and soft/highly porous Chi-C interior. The anisotropic features of each layer, including the porosity, rigidity, rheology, composition, and ionic strength, caused the BiFACIAL films to show spontaneously biased stimuli responses and differential behaviors against biological substances (e.g., blood plasma). The films could be created in situ in live animals and imitated the structural/functional aspects of the representative anisotropic tissues (e.g., skin and blood vessels), providing valuable ECM-like platforms for the creation of favorable environments or for tissue regeneration or disease treatment by effectively manipulating cellular behaviors.

Inverted Quasi‐Spherical Droplets on Polydopamine–TiO2 Substrates for Enhancing Gene Delivery

Devising efficient gene delivery systems is crucial to enhancing the therapeutic efficacy of gene-cell therapy approaches. Herein, inverted quasi-spherical (iQS) droplet systems, which enhance gene delivery efficiencies by reducing the path lengths of gene vectors, mediating motions of vectors at early stages, and raising the contact frequencies of vectors with cells, are developed by adopting the principle of 3D hanging-drop cell culture. Micrometer-sized polydopamine (pDA) holes are created on superhydrophobic titanium isopropoxide (TiO2 )-coated substrates by physical scraping; droplets are loaded on the pDA holes, and inversion of the substrate generates iQS droplets with large contact angles. Both human neural stem cells (hNSCs) and adeno-associated viral vectors are simultaneously incorporated into the iQS droplets to assess gene delivery efficiencies. The steep angles of iQS droplets and enhanced cell/vector contact frequencies facilitate the viral association with hNSCs and enhancing cell-cell interactions, thereby significantly promoting gene delivery efficiencies. Even with reduced viral quantities/exposure times and cell numbers, the iQS droplet systems elicit sufficient gene expression (i.e., interleukin-10). The ability of the iQS droplet systems to maximize beneficial gene delivery effects with minimal materials (e.g., medium, cells, and vectors) should enable their extensive use as a platform for preparing genetically stimulated cellular therapeutics.

Factors Positively Influencing Health Are Associated with a Lower Risk of Development of Metabolic Syndrome in Korean Men: The 2007–2009 Korean National Health and Nutrition Examination Survey

Background The prevalence of metabolic syndrome (MetS) has risen rapidly worldwide, including in South Korea. Factors related to lifestyle are closely associated with the development of MetS. The aim of this study was to investigate the association between MetS and a number of factors positively influencing health, namely non-smoking, low-risk drinking, sufficient sleep, regular exercise, and the habit of reading food labels, among Korean men. Methods This cross-sectional study included 3,869 men from the 2007–2009 Korean National Health and Nutrition Examination Survey. Information on five factors positively influencing their health was obtained using a self-reported questionnaire. We categorized subjects into four groups, depending on the number of positive factors reported (group I, 0–1 factor; group II, 2 factors; group III, 3 factors; group IV, 4–5 factors). Results Men who reported a greater number of positive health factors had better laboratory and anthropometric values than men who reported fewer positive health factors. The prevalence of MetS was 29.1, 27.2, 20.7, and 14.6% in groups I to IV, respectively. Compared to group I, odds ratios (95% confidence intervals) for MetS were 0.96 (0.78–1.19) in group II, 0.67 (0.52–0.87) in group III, and 0.52 (0.35–0.76) in group IV, after adjusting for confounding factors. Odds ratios for abdominal obesity, glucose intolerance, and hypertriglyceridemia were statistically significant. Conclusion A greater number of positive lifestyle factors influencing health were associated with a lower risk of developing MetS, in a nationally representative sample of Korean men.