Search

Resistin-like alpha (Retnla) is a member of the resistin family and known to modulate fibrosis and inflammation. Here, we investigated the role of Retnla in the cardiac injury model. Myocardial infarction (MI) was induced in wild type (WT), Retnla knockout (KO), and Retnla transgenic (TG) mice. Cardiac function was assessed by echocardiography and was significantly preserved in the KO mice, while worsened in the TG group. Angiogenesis was substantially increased in the KO mice, and cardiomyocyte apoptosis was markedly suppressed in the KO mice. By Retnla treatment, the expression of p21 and the ratio of Bax to Bcl2 were increased in cardiomyocytes, while decreased in cardiac fibroblasts. Interestingly, the numbers of cardiac macrophages and unsorted bone marrow cells (UBCs) were higher in the KO mice than in the WT mice. Besides, phosphorylated histone H3(+) cells were more frequent in bone marrow of KO mice. Moreover, adiponectin in UBCs was notably higher in the KO mice compared with WT mice. In an adoptive transfer study, UBCs were isolated from KO mice to transplant to the WT infarcted heart. Cardiac function was better in the KO-UBCs transplanted group in the WT-UBCs transplanted group. Taken together, proliferative and adiponectin-rich bone marrow niche was associated with substantial cardiac recovery by suppression of cardiac apoptosis and proliferation of cardiac fibroblast.

Purpose Previously, we demonstrated that the specific ratio of Korean multi-herbal formula (SR-5) exhibits hepatoprotective properties against ethanol-induced hepatic damage in rats. Chronic and excessive alcohol consumption is a major etiological factor involved in gastric disease and ulcer development induced by the inflammatory response and oxidative stress. Methods The present study evaluated the gastroprotective effects of SR-5 (100, 150, and 200 mg/kg) against hydrochloride acid/ethanol (HCl/EtOH)-induced and indomethacin/hydrochloride acid (INDO/HCl)-induced gastritis in a mouse model and the mechanisms involved. Results All the tested doses of SR-5 significantly inhibited gastric lesions in the HCl/EtOH-induced ulcer model mice. Similarly, all the tested doses of SR-5 significantly inhibited gastric lesions in the INDO/HCl-induced ulcer model mice. Furthermore, mice pretreated with SR-5 had significantly increased gastric levels of enzymatic and nonenzymatic antioxidants, namely, catalase (CAT) and glutathione (GSH), with concomitant reductions in malondialdehyde (MDA) and reactive oxygen species (ROS) levels compared with those in the HCl/EtOH or INDO/HCl group. SR-5 suppressed the expression of nuclear factor-kappa B (NF-κB)/p65, inducible nitric oxide synthase (iNOS), tumor necrosis factor-α (TNF-α), and cyclooxygenase-2 (COX-2) to their normal values. Conclusion These findings are the first to demonstrate the powerful protective effect of SR-5 against gastric injury development and provide hope for clinical application.

Patients with diabetes commonly experience hyposalivation, which induces discomfort in eating, swallowing, dryness, smell, and speaking, as well as increases the incidence of periodontal disease. Dipeptidyl peptidase-4 (DPP4) inhibitors are frequently used as antidiabetic drugs that lower glucose levels by utilizing similar mechanisms; however, additional protective functions of each gliptin have been discovered. In this study, the protective roles of gemigliptin, a DPP4 inhibitor, against salivary dysfunction under diabetic conditions were investigated. Streptozotocin-induced diabetic rats received gemigliptin 10 mg/kg or 100 mg/kg via oral gavage for 3 weeks. The weights of salivary gland tissues, saliva secretion, and antioxidant capacity in salivary glands were reduced after diabetes induction, but were significantly preserved following gemigliptin treatment. In salivary gland analysis, expression of apoptotic proteins, as well as amylase and aquaporin-5 (AQP5) protein expression, were increased following gemigliptin treatment. Furthermore, the number of TUNEL-positive cells decreased after gemigliptin treatment. Therefore, gemigliptin has protective roles against salivary dysfunction observed in diabetes, mediated via antioxidant, anti-apoptotic, and salivary secretion mechanisms. These results may help in selecting a suitable drug for patients with diabetes experiencing salivary dysfunction.

We previously demonstrated that urban particulate matter (UPM) exposure decreases the migration activity and survival of human corneal epithelial cells (HCECs). Herein, we investigated the potential to improve the corneal wound-healing ability of Peucedanum japonicum Thunb. leaf extract (PJE) and its active components on UPM-induced ocular surface damage in vitro and in vivo. PJE effectively assisted wound healing without altering HCEC survival and enhanced catalase (CAT), heme oxygenase 1 (HO1) and glutathione peroxidase 1 (GPX1) antioxidant gene expression. A corneal wound was uniformly induced on the right eye in all experimental animals and divided into eight groups such as two control groups (wounded right eye group—NR and non-wounded left eye group—NL), UPM treated group and PJEs (25, 50, 100, 200, 400 mg/kg) treated groups. Corneal abrasion model rats exposed to UPM showed delayed wound healing compared to unexposed rats, but wound healing was dose-dependently enhanced by PJE oral administration. Seventy-two hours after wound generation, inflammatory cells, apoptotic cells and interleukin-6 (IL-6) expression were increased substantially after UPM exposure, but PJE treatment significantly reduced the wound to an almost normal level while enhancing re-epithelialization without changing corneal thickness. Next, we tried to identify the key molecules for enhancing wound healing through fractionation. The major compounds in the fraction, confirmed by high-performance liquid chromatography (HPLC), were chlorogenic acid (CA), neochlorogenic acid (NCA) and cryptochlorogenic acid (CCA). Each type of CA isomers showed slightly different half maximal effective (EC50) and maximal effective (ECmax) concentrations, and their mixtures synergistically enhanced HCEC migration. Thus, corneal abrasion wound recovery after UPM exposure improved after PJE treatment, and the active PJE components were identified, providing an important basis to develop therapeutics for ocular surface damage using PJE.

Although mesenchymal stem cells (MSC) have been shown to be safe in preclinical studies of cardiovascular disease, multiple meta-analyses have debated whether functional improvement is significant or not. The cardiac differentiation from MSC is achievable using cardiogenic factors, however, the high cost and long culture period may limit the applications. Here, we developed a novel method to optimize the therapeutic outcome for myocardial infarction (MI). Treatment of MSC with apicidin, a histone deacetylase inhibitor, dramatically increased the expressions of cardiac markers such as GATA4, Nkx2.5, and cardiac troponin I (cTnI). In AC/MSC, stemness-related genes and yes-associated protein (YAP), a potent oncogene that drives cell proliferation, were significantly suppressed. Furthermore apicidin treatment or YAP knockdown downregulated miR-130a expression followed by induction of cardiac markers in MSC. In the comparison study, we found that both cardiac gene induction and angiogenesis were most prominent in the mixture of non-treated MSC and AC/MSC (Mix). Using mouse MI model, we show that application of Mix was strongly associated with cardiac differentiation of injected MSC and improved cardiac performance. Our results suggest that suppression of YAP/miR-130a shifts MSC cell fate toward cardiac lineage and identify apicidin as a potential pharmacological target for therapeutic development.

The renal accumulation of advanced glycation end products (AGEs) is a causative factor of various renal diseases, including chronic kidney disease and diabetic nephropathy. AGE inhibitors, such as aminoguanidine and pyridoxamine, have the therapeutic activities for reversing the increase in renal AGE burden. This study evaluated the inhibitory effects of ethyl pyruvate (EP) on methylglyoxal- (MGO-) modified AGE cross-links with proteins in vitro. We also determined the potential activity of EP in reducing the renal AGE burden in exogenously MGO-injected rats. EP inhibited MGO-modified AGE-bovine serum albumin (BSA) cross-links to collagen (IC50=0.19±0.03 mM) in a dose-dependent manner, and its activity was stronger than aminoguanidine (IC50=35.97±0.85 mM). In addition, EP directly trapped MGO (IC50=4.41±0.08 mM) in vitro. In exogenous MGO-injected rats, EP suppressed AGE burden and MGO-induced oxidative injury in renal tissues. These activities of EP on the MGO-mediated AGEs cross-links with protein in vitro and in vivo showed its pharmacological potential for inhibiting AGE-induced renal diseases.

We investigated how surface anchoring strength affects the electro-optic (EO) characteristics of a fringe-field switching (FFS) mode. Unlike IPS mode that only azimuthal anchoring mainly contributes to the EO performances, both azimuthal and polar anchoring energies play an important role such that the transmittance increases with decreasing magnitude of azimuthal energy but increasing polar anchoring energy in the FFS mode when using a LC with positive dielectric anisotropy. In addition, weak anchoring at the electrode edge may result in change in initial LC optic axis by applied voltage stress so local control of anchoring energy is proposed.

We investigated the time-dependent deleterious ocular changes induced by urban particulate matter (UPM) in vitro and in vivo. UPM treatment decreased human corneal epithelial cell migration and survival. Fluorescein scores were consistently increased by UPM application for 16 weeks. One week of rest at 2 or 4 weeks led to a recovery trend, whereas two weeks of rest at 8 weeks induced no change. UPM treatment decreased the tear film break-up time at 2 weeks, which was thereafter maintained until 16 weeks. No changes were found after periods of rest. UPM-treated eyes exhibited greater corneal epithelium thickness than normal eyes at 2 weeks, which recovered to normal at 4 and 8 weeks and was significantly decreased at 16 weeks. Apoptotic cell number in the epithelium was increased at 2 weeks, which remained constant except at 8 weeks. IL-6 expression in the cornea of the right eye continually increased for 16 weeks, and significant recovery was only observed at 8 weeks after 2 weeks of rest. Ocular pressure was significantly increased in the right eye at 12 and 16 weeks. Topical UPM application to the eye induced deleterious changes to various closely related parts of the eye.

This study identified microRNAs involved in myocardial infarction (MI) through a novel system-level approach using RNA sequencing data in an MI mouse model. This approach involved the extraction of DEGs and DEmiRs from RNA-seq data in sham and MI samples and the subsequent selection of two miRNAs: miR-30-5p (family) and miR-142a-5p, which were downregulated and upregulated in MI, respectively. Gene Set Enrichment Analysis (GSEA) using the predicted targets of the two miRNAs suggested that apoptosis is an essential gene ontology (GO)-associated term. In vitro functional assays using neonatal rat ventricular myocytes (NRVMs) demonstrated that miR-30-5p is anti-apoptotic and miR-142a-5p is pro-apoptotic. Luciferase assays showed that the apoptotic genes, Picalm and Skil, and the anti-apoptotic genes, Ghr and Kitl, are direct targets of miR-30-5p and miR-142a-5p, respectively. siRNA studies verified the results of the luciferase assays for target validation. The results of the system-level high throughput approach identified a pair of functionally antagonistic miRNAs and their targets in MI. This study provides an in-depth analysis of the role of miRNAs in the pathogenesis of MI which could lead to the development of therapeutic tools. The system-level approach could be used to identify miRNAs involved in variety of other diseases.

High glucose-insulted bone marrow-derived mesenchymal stem cells (BMCs) showed impaired angiogenesis along with downregulation of stem cell factor (SCF). This study was designed to determine the involvement of microRNAs (miR), which are actively involved in the physiological function of stem cells. We observed that miR-34c was significantly induced by high glucose treatment and blunted tube formation of BMCs. Stem cell factor (SCF) was confirmed as a target of miR-34c by 3'-UTR promoter analysis and Western blot. SCF knockdown by siRNA induced Kruppel-like factor 4 (KLF4) and resulted in the blockade of angiogenesis of BMCs. Sequentially, KLF4 overexpression completely blocked tube formation through inducing PAI-1 (plasminogen activator inhibitor-1). To study the action of miR-34c in terms of the therapeutic potential of BMCs, myocardial infarction (MI) was induced by ligation of the coronary artery in nude mice, BMCs transfected with miR-control or miR-34c were injected into the infarcted myocardium 7 days later, and histological studies were performed 2 weeks later. Cardiac fibrosis was 18.24±4.7% in the miR-34c-BMC group and 10.01±0.2% in the miR-control-BMC group (p

Stem cell therapy has emerged as a potential modality for myocardial infarction treatment. Mesenchymal stem cells (MSCs) exert reparative actions in the injured myocardium mainly through the secretion of paracrine factors. In addition, the overexpression of connexin 43 (Cx43), a gap junction protein, promotes cardiac repair and function restoration. It is known that MSCs in a spheroid form, which have enhanced cell–cell interaction, exhibit enhanced expression of paracrine factors and Cx43. However, cell-extracellular matrix (ECM) interactions, which also contribute to growth factor expression, are very limited in MSC spheroids. Reduced graphene oxide (RGO) shows high affinity toward ECM proteins, such as fibronectin (FN), and high electrical conductivity. In this study, by incorporating FN-adsorbed RGO flakes into MSC spheroids, it is possible to enhance the cell–ECM interactions and, subsequently, the paracrine factor expression in the MSCs in spheroids. Cx43 is also upregulated likely due to the enhanced paracrine factor expression and electrical conductivity of RGO. The injection of MSC–RGO hybrid spheroids into the infarcted hearts enhances cardiac repair compared with the injection of RGO flakes or MSC spheroids. This study demonstrates that RGO can effectively improve the therapeutic efficacy of MSCs for ischemic heart diseases.

Although cell therapy is emerged for cardiac repair, its efficacy is modest by intracoronary infusion. Therefore, we established the intramyocardial delivery technique using a left ventricular (LV) mapping system (NOGA® XP) using 18 pigs. After adipose tissue-derived mesenchymal stem cells (ATSCs) were delivered intramyocardially to porcine infarcted heart, LV ejection fraction (EF) was increased, and LV chamber size was decreased. We proved the therapeutic effect of intramyocardial injection of ATSC through a LV mapping system in the porcine model for the first time in Korea. The adoption of this technique may accelerate the translation into a clinical application in the near future., Graphical Abstract

Type 2 diabetes mellitus (T2DM) significantly impacts on human health and patient numbers are predicted to rise. Discovering novel drugs and targets for treating T2DM is a research priority. In this study, we investigated targeting of the glycolysis enzyme, enolase, using the small molecule ENOblock, which binds enolase and modulates its non-glycolytic ‘moonlighting’ functions. In insulin-responsive cells ENOblock induced enolase nuclear translocation, where this enzyme acts as a transcriptional repressor. In a mammalian model of T2DM, ENOblock treatment reduced hyperglycemia and hyperlipidemia. Liver and kidney tissue of ENOblock-treated mice showed down-regulation of known enolase target genes and reduced enolase enzyme activity. Indicators of secondary diabetic complications, such as tissue apoptosis, inflammatory markers and fibrosis were inhibited by ENOblock treatment. Compared to the well-characterized anti-diabetes drug, rosiglitazone, ENOblock produced greater beneficial effects on lipid homeostasis, fibrosis, inflammatory markers, nephrotoxicity and cardiac hypertrophy. ENOblock treatment was associated with the down-regulation of phosphoenolpyruvate carboxykinase and sterol regulatory element-binding protein-1, which are known to produce anti-diabetic effects. In summary, these findings indicate that ENOblock has potential for therapeutic development to treat T2DM. Previously considered as a ‘boring’ housekeeping gene, these results also implicate enolase as a novel drug target for T2DM.

Background and Objectives: Diabetes is reported to reduce the function or number of progenitor cells. We compared the gene expression patterns of bone marrow-derived mesenchymal stem cells from diabetic (DM-BMCs) and healthy (non-DM-BMCs) rats and suggested Angiopoietin-like 4 (Angptl4) could be a responsible factor for impaired angiogenesis of DM-BMCs. Subjects and Methods: BMCs were isolated from DM or non-DM rat, and in vitro angiogenesis activity was compared by tube formation assay on Matrigel and complementary deoxyribonucleic acid expression was analyzed by microarray with or without oxytocin treatment. Human BMCs (hBMCs) were treated with high glucose, and were performed polymerase chain reaction, Western blot, and enzyme-linked immunosorbent assay. Angptl4 plasmid DNA and micro ribonucleic acid-132 (miR-132) were transfected to immortalized hBMCs. Results: In vitro angiogenesis assay showed the impaired tube formation in DM-BMCs, and slightly recovery by oxytocin treatment. Angptl4, an adipokine, was upregulated in DM-BMCs compared to non-DM-BMCs. Oxytocin treatment reduced Angptl4 in DM-BMCs. In hBMCs, overexpression of Angptl4 attenuated the tube formation. In addition to Angptl4, miR-132 was increased by high glucose treatment. Collectively, high glucose resulted in impaired tube formation through miR-132 induction and Angptl4 upregulation in BMCs. Conclusion: Our results show that the angiogenic activity of BMCs is impaired by high glucose stress, which would be mediated by Angptl4 and miR-132. (Korean Circ J 2014;44(3):177-183)

Aims We elucidated the therapeutic potential of human umbilical vein endothelial cells (HUVECs) for ameliorating progressive heart failure in a myocardial infarction (MI) rat model. Main methods MI was induced by ligation of left anterior descending artery, and HUVEC was transplanted 1 week after MI. Cardiac function was evaluated by echocardiography, and histological analyses were performed. Key findings Phosphate-buffered saline (MI-V, n = 5) or HUVEC (MI-HV, n = 5) were injected into the border zone and infarcted area 7 days after ligation of the left coronary artery in rats. The MI-HV group showed attenuation of left ventricular (LV) remodeling compared with the MI-V group. In the infarcted myocardium, a few of injected HUVEC was retained up to 28 days. The ratios of matrix metalloproteinase (MMP)-2 or MMP-9 to tissue inhibitor of metalloproteinase (TIMP)-1 or TIMP-3 were decreased in the MI-HV group compared with the MI-V group. In vivo zymography analysis showed that HUVEC transplantation decreased the activities of MMP-2 and MMP-9. In immunohistochemistry, decreased MMP-2 and increased TIMP-1 and TIMP-3 expression were observed at 48 h after HUVEC transplantation. These effects on MMP/TIMP balance were inhibited by L-NAME administration (an eNOS inhibitor, 10 mg/kg). NOS inhibition decreased the protein expressions of TIMP-1 and TIMP-3 but did not change the protein expressions of MMP-2 and MMP-9. Significance Our data suggest that altered balance between MMP and TIMP by HUVEC transplantation contributed to attenuation of ventricular remodeling after MI via eNOS.

We examined whether a shift in macrophage phenotype could be therapeutic for myocardial infarction (MI). The mouse macrophage cell line RAW264.7 was stimulated with peptidoglycan (PGN), with or without 5-azacytidine (5AZ) treatment. MI was induced by ligation of the left anterior descending coronary artery in rats, and the rats were divided into two groups; a saline-injection group and a 5AZ-injection group (2.5mg/kg/day, intraperitoneal injection). LV function was evaluated and immunohistochemical analyses were performed 2weeks after MI. Cardiac fibrosis was induced by angiotensin II (AngII) infusion with or without 5AZ (5mg/kg/day) in mice. Nitric oxide was produced by PGN, which was reduced by 77.87% after 5AZ treatment. Both induction of inducible nitric oxide synthase (iNOS) and iNOS promoter activity by PGN were inhibited by 5AZ. Ejection fraction (59.00 +/- 8.03% versus 42.52 +/- 2.58%), contractility (LV dP/dt-max, 8299.76 +/- 411.56mmHg versus 6610.36 +/- 282.37mmHg) and relaxation indices (LV dP/dt-min, -4661.37 +/- 210.73mmHg versus -4219.50 +/- 162.98mmHg) were improved after 5AZ administration. Cardiac fibrosis in the MI+5AZ was 8.14 +/- 1.00%, compared with 14.93 +/- 2.98% in the MI group (P

The cardiac microenvironment includes cardiomyocytes, fibroblasts and macrophages, which regulate remodeling after myocardial infarction (MI). Targeting this microenvironment is a novel therapeutic approach for MI. We found that the natural compound derivative, BIO ((2′Z,3′E)-6-Bromoindirubin-3′-oxime) modulated the cardiac microenvironment to exert a therapeutic effect on MI. Using a series of co-culture studies, BIO induced proliferation in cardiomyocytes and inhibited proliferation in cardiac fibroblasts. BIO produced multiple anti-fibrotic effects in cardiac fibroblasts. In macrophages, BIO inhibited the expression of pro-inflammatory factors. Significantly, BIO modulated the molecular crosstalk between cardiac fibroblasts and differentiating macrophages to induce polarization to the anti-inflammatory M2 phenotype. In the optically transparent zebrafish-based heart failure model, BIO induced cardiomyocyte proliferation and completely recovered survival rate. BIO is a known glycogen synthase kinase-3β inhibitor, but these effects could not be recapitulated using the classical inhibitor, lithium chloride; indicating novel therapeutic effects of BIO. We identified the mechanism of BIO as differential modulation of p27 protein expression and potent induction of anti-inflammatory interleukin-10. In a rat MI model, BIO reduced fibrosis and improved cardiac performance. Histological analysis revealed modulation of the cardiac microenvironment by BIO, with increased presence of anti-inflammatory M2 macrophages. Our results demonstrate that BIO produces unique effects in the cardiac microenvironment to promote recovery post-MI.

Rationale: Myocardial infarction (MI) induces cardiac remodeling, which is regulated by the cardiac microenvironment and results in scarring and loss of cardiac function. Targeting the microenvironment represents a novel therapeutic approach. Objective: To investigate the therapeutic effect of a natural compound derivative, BIO [(2’Z,3’E)-6-Bromoindirubin-3′-oxime], on cardiac microenvironment cells and remodeling post-MI. Methods and Results: Using a series of co-culture studies, BIO was shown to induce proliferation in cardiomyocytes and, conversely, inhibit proliferation in cardiac fibroblasts. In addition, BIO produced anti-fibrotic effects in the fibroblasts, such as reduced motility and expression changes in fibrosis-related factors. In macrophages, BIO inhibited the expression of pro-inflammatory inducible nitric oxide synthase. Interestingly, BIO modulated molecular crosstalk between cardiac fibroblasts and differentiating macrophages to increase expression of anti-inflammatory M2 macrophage markers. In the optically transparent zebrafish-based model of heart failure, BIO induced cardiomyocyte proliferation to recover survival rate. BIO is a known glycogen synthase kinase-3β inhibitor, but these effects could not be recapitulated using the classical inhibitor, lithium chloride; indicating novel, potential therapeutic effects of BIO on remodeling. We characterized these novel effects of BIO as differential modulation of p27 expression and potent induction of interleukin-10 in microenvironment cells. In rat MI model, BIO reduced fibrosis and improved cardiac performance. Histological analysis revealed a greater presence of anti-inflammatory M2 macrophages in the infarction zone. BIO treatment also reduced serum levels of pro-fibrotic interleukin-6. Conclusions: BIO differentially activates signaling pathways in cardiomyocytes, cardiac fibroblasts and cardiac macrophages to reduce fibrosis, increase cardiomyocyte proliferation and promote recovery post-MI.

Wide-view (WV) film, which was introduced by Fuji Co., has been commercialized to block light leakage of twisted nematic (TN)-liquid crystal (LC) cells in a dark state when the viewing angles are in the off-axis direction. In this investigation, we designed an optical compensation structure of a TN-LC cell with an improved γ-curve, as well as a viewing angle property in the dark state. Basically, we used a pair of optical films consisting of a positive and a negative A-plate in order to avoid affecting the viewing angle property in the dark state. Then, we optimized the positive and negative A-plate to improve the viewing angle property in the gray levels by calculating polarization variations as a function of the optical axis and the retardation of the pair of the A-plates. From this calculation, we were able to show that the proposed normally white (NW) WV-TN cell exhibits wide viewing angle performance, including good γ-curve stability.

In order to compensate for light leakage in the oblique viewing directions of the dark state of the horizontal-switching mode such as the in-plane switching and fringe field switching modes. The viewing angle performance of the horizontal-switching mode with an compensation film has been evaluated on a case by case basis according to the retardation values of the films. Consequently, we found that a much better dark state can be achieved by using an optimised compensation film.

Dynamical behavior of the liquid crystal director on the slit of the patterned vertical alignment liquid crystal cell are very unstable because there is a strong competition of strain energy of liquid crystal director. In this paper, we proved a unit patterned vertical alignment cell with stable dynamic behaviors by using the defect trap structure experimentally. In addition, we also inspected electro-optical instability of the proposed patterned vertical alignment liquid crystal cell as functions of a width and a length of the slit pattern. As a result, we could optimize the slit pattern of the patterned vertical alignment liquid crystal cell with the defect trap.

In this paper, we propose an in-plane switching (IPS) mode for liquid crystal displays (LCDs) that, in principle, is free of retardation of the LC cell. Basically, the optical configuration of the LC cell consists of an A-plate and an LC layer for switching between the dark and bright states. We could achieve a fast response time compared with the conventional in-plane LC cell because the free retardation condition of the proposed LC cell enables us to reduce the cell gap even by quarter-wave retardation without any change of the optimized LC material in the transmissive mode. Experiments for verification of the proposed in-plane switching LC cells have shown a significant reduction of the rising time and falling time simultaneously due to the small cell gap. Furthermore, we also proposed an optical configuration for wide viewing property of the retardation free IPS LCD by applying the optical films. We proved the wide-view property of the retardation free IPS LCD by comparing its optical luminance with the calculated optical property of the conventional IPS LCD.

We propose a high speed In-Plane Switching (IPS) liquid crystal display (LCD) with free retardation and wide view property. The proposed IPS mode can considerably reduce the response time of the LC cell. The optical configuration of the proposed IPS LC cell is composed of an A-plate and LC layer. We could achieve a fast response time without any change of an LC material in transmissive mode. The calculated and experimental results for an optical response of the proposed LC cell have shown a significant reduction of the falling time. Also, we investigated an optical configuration for wide viewing angle property of the high speed IPS LCD and compared iso-luminance with the conventional IPS LC cell.

A device for operating viewing angle-switchable liquid crystal displays has been developed based on an optically isotropic liquid crystal (OILC). The device comprises two panels, main and switching. Depending upon the voltage applied, the optical state of the OILC layer in the switching panel can be changed to the anisotropic uniaxial state, taking on the role of a positive C film. In this manner luminance at oblique polar angles can be suppressed, resulting in a dark image at an off-normal axis, at the same time retaining good image quality in the normal direction. Depending on the switching of the OILC layer, wide or narrow angles of viewing can be obtained.

The polymer-stabilized blue phase liquid crystal (BPLC) cell has advantages such as sub-millisecond response time, wide viewing angle and no rubbing process for the alignment of liquid crystals. However, high operating voltage and low kerr constant of the polymer-stabilized blue phase liquid crystal deteriorate the electro-optical characteristic of the polymer-stabilized BPLC cell. In this paper, we proposed novel zig-zag electrode in cell layout and confirmed that proposed electrode shape could reduce an over 25 percent of operating voltage for BPLC cell without degradation of tranmittance by using Kerr constant simulation.

Dry eye disease is affected by a broad range of causes such as age, lifestyle, environment, medication and autoimmune diseases. These causes induce tear instability that activates immune cells and promotes expression of inflammatory molecules. In this study, we investigated the therapeutic effects of an ethanolic extract of Aucuba japonica (AJE) and its bioactive compound, aucubin, on dry eye disease. The human corneal cells were exposed to desiccation stress induced by exposing cells to air, so that viability was decreased. On the other hand, pre-treatment of AJE and aucubin restored cell survival rate depending on the dose under the dry condition. This result was confirmed again by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. The mRNA expression of inflammatory molecules was reduced by the pretreatment of AJE and aucubin under the dry state. The therapeutic effects of AJE and aucubin were examined in the animal model for dry eye induced by unilateral excision of the exorbital lacrimal gland. Declined tear volumes and corneal irregularity in the dry eye group were fully recovered by the administration of AJE and aucubin. The apoptotic cells on the cornea were also decreased by AJE and aucubin. Therefore, this study suggests that administration of AJE can be a novel therapeutic for dry eye disease and that the pharmacological activities of AJE may be in part due to its bioactive compound, aucubin.

Lowering threshold voltage and operating voltage is a critical issue for blue phase liquid crystal (BP LC) because the Kerr constant of liquid crystal mixture is not so high. In order to switch BP LC from optically isotropic to anisotropic state, in-plane electric field should be generated by interdigitated electrodes in general, however, the operating voltage is high and transmittance is relatively low. In this paper, the BP LC driven by fringe electric field is studied as one of the solutions for those problems. Detailed analysis of voltage-dependent characteristics between two devices has been performed.

In this paper, a single cell-gap and single gamma transflective liquid crystal displays (LCDs) associated with fringe-field switching (FFS) device is proposed. The device utilizes unique characteristic of the FFS device in which the twist angle of LC director is dependent on electrode position in on state. With optimization of pixel electrode width and distance between them, the LC director can be rotated about 22.5° and 45° of twist angles depending on electrode positions. Consequently, the parts with low and high twist angle could be played for the reflective ( R ) and transmissive ( T ) regions respectively, realizing a high image quality transflective display.

Colour tracking behaviour is observed in most liquid crystal displays. In in-plane switching and vertical alignment devices, the colour chromaticity in the normal direction changes linearly from bluish- to yellowish-white as the grey level is increased from the dark to white state. Interestingly, abnormal behaviour in colour tracking is observed in fringe-field switching devices using a liquid crystal with positive dielectric anisotropy, such that the colour chromaticity changes from bluish to yellowish up to a certain grey level, then turns around and becomes bluish-white as the grey level is further increased to the fully white state. According to our theoretical and experimental results, this ‘turn around’ effect in the colour tracking of the fringe-field switching mode is associated with the generation of a tilt angle of the liquid crystal molecules with increasing voltage in the electrode position where the light modulation is associated with the polarisation rotation.

Macrophages are actively involved in inflammatory responses during the progression of cardiac injury, including myocardial infarction (MI). A previous study showed that 5-azacytidine (5AZ), a DNA methylation inhibitor, can ameliorate cardiac injury by shifting macrophages toward an anti-inflammatory phenotype via iNOS inhibition. Here, we show that the beneficial effect of 5AZ is associated with sumoylation of interferon regulatory factor-1 (IRF1) in macrophages. IRF1 is a critical transcription factor for iNOS induction and is antagonized by IRF2. In the stimulated macrophages, IRF1 accumulated in the nucleus without degradation by 5AZ treatment. In animal study, 5AZ administration resulted in significant improvements in cardiac function and fibrosis. IRF1-expressing macrophages were more abundant in the 5AZ-treated MI group than in the PBS-treated MI group. Because sumoylated IRF1 is known to mimic IRF2, we examined the IRF1 sumoylation. Sumoylated IRF1 was resistant to degradation and significantly increased in the 5AZ-treated MI group. Collectively, 5AZ had a protective effect after MI by potentiation of IRF1 sumoylation and is suggested as a novel therapeutic intervention for cardiac repair.

Pressure overload in the heart induces pathological hypertrophy and is associated with cardiac dysfunction. Apoptosis and fibrosis signaling initiated by the endoplasmic reticulum stress (ERS) is known to contribute to these maladaptive effects. The aim of this study was to investigate whether reduction of ERS by a known chemical chaperone, tauroursodeoxycholic acid (TUDCA) can attenuate pressure overload-induced cardiac remodeling in a mouse model of transverse aortic constriction (TAC). Oral administration of TUDCA at a dose of 300 mg/kg body weight (BW) in the TUDCA-TAC group reduced ERS markers (GRP78, p-PERK, and p-elf2 alpha), compared to the Vehicle (Veh)-TAC group. TUDCA administration, for 4 weeks after TAC significantly reduced cardiac hypertrophy as shown by the reduced heart weight (HW) to BW ratio, and expression of hypertrophic marker genes (ANF, BNP, and alpha-SKA). Masson's trichrome staining showed that myocardial fibrosis and collagen deposition were also significantly reduced in the TUDCA-TAC group. We also found that TUDCA significantly decreased expression of TGF-beta signaling proteins and collagen isoforms. TUDCA administration also reduced cardiac apoptosis and the related proteins in the TUDCA-TAC group. Microarray analysis followed by gene ontology (GO) and pathway analysis demonstrated that extracellular matrix genes responsible for hypertrophy and fibrosis, and mitochondrial genes responsible for apoptosis and fatty acid metabolism were significantly altered in the Veh-TAC group, but the alterations were normalized in the TUDCA-TAC group, suggesting potential of TUDCA in treatment of heart diseases related to pressure-overload.