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Background/Aim To analyse ultrawide-field fluorescein angiography (UWF-FA) images of diabetic retinopathy using a novel software that automatically calculates microaneurysm (MA) and non-perfusion area. Methods Two hundred UWF-FA images of treatmentnaïve diabetic retinopathy (38 proliferative diabetic retinopathy and 162 non-proliferative diabetic retinopathy) from 120 patients (mean age 54.22; 80 male) were analysed using novel software to determine the number of MAs, area of capillary non-perfusion (ischaemic index) and number of neovascularisations. Each result was compared according to its retinal regions. Results For the total retina, the mean number of MAs was 292.02 (±175.57) and the ischaemic index was 59.42% (±14.78%). Most MAs were located in the mid-peripheral retina (80.54%); however, the density of MAs was highest in the posterior pole (p<0.001). The ischaemic index was highest in the peripheral retina (89.19%), followed by mid-periphery (50.65%) and posterior pole (1.85%). Patients with diabetic macular oedema (DME) presented more MA and a greater ischaemic index (p<0.001, each) than those without DME. Conclusion The automated software allowed prompt and quantitative analysis of UWF-FA images of DMR. MAs were most frequent in the nasal and mid-peripheral retina, with their density being highest in the posterior pole and nasal retina. Ischaemic index increased with distance from the posterior pole, showing strong correlation with central foveal thickness in all retinal areas except the posterior pole. [ABSTRACT FROM AUTHOR]

Aims To investigate macular vascular integrity using optical coherence tomography angiography (OCTA) in patients undergoing vitrectomy for idiopathic epiretinal membrane (ERM) removal and to determine its association with structural and visual outcomes. Methods Forty-three patients with unilateral ERM who were followed for ≥6 months after surgery were included. Ophthalmological evaluations included best- corrected visual acuity (BCVA) and spectral-domain OCT (SD-OCT) before surgery and 6 months after surgery. We obtained en face OCTA images of the superficial capillary plexus (SCP) and deep capillary plexus (DCP) for both eyes 6 months after ERM removal. We compared eyes with ERM to unaffected fellow eyes as controls and used interocular differences in the analyses. Results Compared with the fellow eyes, eyes with ERM after surgery had a lower parafoveal vascular density (VD) and a smaller foveal avascular zone (FAZ) area in both SCP and DCP (all p<0.001). Interocular differences in the FAZ area and parafoveal VD were correlated with preoperative and postoperative central foveal thicknesses (all p<0.05). In addition, interocular differences in macular vascular integrity had a tendency to be correlated with SD-OCT parameters of the inner retinal layers. Finally, greater interocular differences in the FAZ area and parafoveal VD of both plexuses were significantly associated with worse postoperative BCVAs (all p<0.05). Conclusions Assessing macular capillary plexuses via OCTA may be useful to quantify structural changes of the inner retinal layer and predict visual function in patients undergoing ERM removal surgery. [ABSTRACT FROM AUTHOR]

Aims To investigate the structural changes of the superficial capillary plexuses (SCP) and deep capillary plexuses (DCP) using optical coherence tomography (OCT) angiography (OCTA) in patients with idiopathic macular hole (MH) after surgery, determine the factors related to changes of macular capillary plexuses and evaluate its association with postoperative visual outcomes. Methods Thirty-three patients with unilateral MH who were followed for ≥6 months after surgery were included. Ophthalmologic evaluations included best corrected visual acuity (BCVA) and spectral-domain OCT before surgery and 6 months postsurgery. En face OCTA images were obtained for both eyes at 6 months postsurgery, and the postoperative foveal avascular zone (FAZ) area and parafoveal vascular density were identified. Results Compared with fellow eyes, eyes after MH surgery had a smaller FAZ area in both SCP and DCP (p<0.05 for all). The FAZ area was positively correlated with postoperative foveal thickness of the whole, inner and outer layers (p<0.05 for all). In the parafoveal region, eyes after MH surgery had a tendency to have lower parafoveal vascular density, particularly in DCP (p=0.019). The parafoveal vascular density in DCP was positively correlated with retinal thickness of the whole, inner and outer layers (p<0.05 for all). Correlations between BCVA and FAZ area in both SCP and DCP were significant 6 months after MH surgery (p<0.05 for all). Conclusion Assessment of macular capillary plexuses using OCTA may be useful for monitoring retinal structural and functional changes in MH. [ABSTRACT FROM AUTHOR]

Femtosecond laser-interference crystallization (FLIC) was used to form a spatially periodic magnetic structure by selectively crystallizing a paramagnetic amorphous Co2MnSi thin film. Regularly spaced alternating lines of polycrystalline and microcrystalline regions with a periodicity of 2 μm were produced by FLIC. The crystalline region composed of ∼100-nm-sized grains contained a nonequilibrium ferromagnetic phase intermixed with β-Mn. The areas between the crystallized lines also received sufficient energy, crystallizing into a microcrystalline state with its grain size ranging from 1 to 5 nm. The magnetic force microscopy of the samples clearly revealed the one-dimensional periodic magnetic domains resulting from the modulated microstructure. [ABSTRACT FROM AUTHOR]

Structural changes of and the interactions between organic materials in liquid crystal display panel after UV exposure were systematically investigated using FT-IR, XPS, AFM, and LC-ESI-MS. When the photo-curing of the sealant was imperfect during the assembly of LCD panel, both the components in the sealant such as UV-initiator contaminated the LC's and the stray UV light oxidized the benzene rings and other chemical bonds in the polymer backbone of the alignment layer. This resulting contamination of LC's and degradation of the alignment layer could disturb the pretilt angle of the VA-mode LC's and cause the display defects on the LCD panel. In this regard, careful control of the photo-curing of the sealant will be required for precise alignment of the LCD panel and better performance of the display. [ABSTRACT FROM AUTHOR]

Clostridium difficile toxin A causes acute colitis associated with intense infiltrating neutrophils. Although dendritic cells (DCs) play an important role in the regulation of inflammation, little is known about the effects of toxin A on the maturation and neutrophil-attracting chemokine expression in DCs. This study investigated whether C. difficile toxin A could influence the maturation of mouse bone-marrow-derived DCs and chemokine CXCL2 expression. Toxin A increased the DC maturation which was closely related to CXCL2 upregulation. Concurrently, toxin A activated the signals of p65/p50 nuclear factor kappa B (NF-κB) heterodimers and phospho-IκB kinase (IKK) in DCs. The increased DC maturation, CXCL2 expression, and neutrophil chemoattraction were significantly downregulated in the NF-κB knockout mice. In addition, toxin A activated the phosphorylated signals of mitogen-activated protein kinases (MAPKs), such as ERK, p38, and JNK. Of all three MAPK signals, p38 MAPK was significantly related to DC maturation. Thus, suppression of p38 activity using SB203580 and siRNA transfection resulted in the significant reduction of IKK activity, DC maturation, and CXCL2 upregulation by toxin A. These results suggest that p38 MAPK may lead to the activation of IKK and NF-κB signaling, resulting in enhanced DC maturation and CXCL2 expression in response to C. difficile toxin A stimulation. [ABSTRACT FROM AUTHOR]

Clostridium difficile toxin A causes acute colitis associated with intense infiltration of neutrophils. Although C. difficile toxin A is known to induce nuclear factor-kappaB-mediated chemokine expression in intestinal epithelial cells, little is known about its effect on the regulation of activator protein-1 (AP-1) by mitogen-activated protein kinase (MAPK). In the present study, we investigated whether the MAPK and AP-1 signaling pathway is involved in interleukin (IL)-8 expression and enteric inflammation in response to stimulation with toxin A. Toxin A activated MAPK and AP-1 composed of c -Jun/c- Fos heterodimers in primary intestinal epithelial cells and HT-29 cell lines. Transfection with mutant genes for Ras, c -Jun, p38, or c -Jun N-terminal kinase (JNK) significantly inhibited C. difficile toxin A-induced activation of AP-1 and expression of IL-8 in HT-29 cell lines. Furthermore, the p38 inhibitor SB203580 attenuated toxin A-induced inflammation in vivo in the mouse ileum, evidenced by a significant decrease in neutrophil infiltration, villous destruction, and mucosal congestion. Our results suggest that the Ras/MAPK cascade acts as the upstream signaling for AP-1 activation and IL-8 expression in toxin A-stimulated intestinal epithelial cells and may be involved in the development of enteritis after infection with toxin A-producing C. difficile. [ABSTRACT FROM AUTHOR]

Amorphous Co[sub78-x]Mn[subx]B[sub10]Si[sub12] (x = 10, 15, 20, 25) alloys were fabricated using the melt- spinning process in order to study the effect of Mn addition on the crystallization of the Co-rich amorphous alloy. In general, thermal stability of the aniorphous structure was greatly improved by the presence of Mn, delaying the onset of crystallization by 100 °C as the Mn content was increased froni 10 to 25 at. pct. Due to the delay of crystallization, Co[sub53]Mn[sub25]B[sub10]Si[sub12], unlike other compositions, exhibited a uniform grain size distribution, relatively free of any struct;ural defects in the fully devitrified state. It was also found that Co[sub2]MnSi was the first crystalline phase to nucleate in the amorphous matrix and became the increasingly dominant phase in the fully devitrified structure as Mn content was increased. Saturation magnetization of the as-cast alloys decreased with increasing Mn content and eventually becanie paramagnetic at 20 at. pct. During devitrification, all of the studied alloys became ferromagnetic from nucleation of Co[sub2]MnSi and Co. The magnetic transition temperatures correlated well to the observed changes in the microstructure. [ABSTRACT FROM AUTHOR]

The purpose of this study was to predict the acoustic performance of a fully lined rectangular plenum chamber having inlet and outlet ports at arbitrary locations. Because no exact analytic solution exists for this reactive-resistive silencer configuration, numerical methods are only available for a three-dimensional analysis. The lined plenum chamber was modeled as a piston-driven rectangular tube without mean flow and the acoustic pressure in the lined chamber was obtained by superposing the acoustic pressures due to each harmonically fluctuating piston. Air pore and skeleton material of the porous liner was reduced to an equivalent medium; thus, its acoustic characteristic was given by bulk-reacting liner properties. A single weak variational statement, which satisfies the conditions of the oscillating piston and all necessary boundary conditions, was developed. The Rayleigh-Ritz method was employed as the numerical scheme for the derived variational statement. Using a transfer matrix and measured material properties, all possible types of lined plenum chambers were tested. Computed results were compared with the predicted transmission loss by the locally reacting liner model and experimental results. Transmission loss predicted by the Rayleigh–Ritz method using the bulk-reacting liner model agreed well with the measured one. [ABSTRACT FROM AUTHOR]

To elucidate the role of Toll-like receptor 9 (TLR9) activation along with the intracellular signaling pathways triggered by CpG DNA in CD34+ cells, we investigated whether synthetic oligodeoxynucleotides (ODNs), containing unmethylated CpG motifs, could induce IL-8 expression in CD34+ cells through mitogen-activated protein kinase (MAPK) or nuclear factor-κB (NF-κB) pathway. We demonstrated evidence for the first time that CD34+ cells constitutively expressed TLR9. Exposure of the cells to CpG ODN resulted in a time- and dose-dependent increase of IL-8 expression, and activation of phosphorylated ERK1/2 and phosphorylated p38. In addition, CpG ODN stimulated AP-1, but not NF-κB, signals. Moreover, inhibitors of MAPK (U0126 and SB203580) significantly reduced the IL-8 production, while the inhibition of NF-κB (pyrrolidinedithiocarbamate and retrovirus containing dominant-negative IκBα plasmid) did not affect the IL-8 expression increased by CpG ODN. Moreover, co-stimulation with LPS and CpG synergistically up-regulates IL-8 in CD34+ cells. These results suggest that CpG DNA, acting on TLR9, activates CD34+ cells to express IL-8 through MAPK-dependent and NF-κB-independent pathways. [ABSTRACT FROM AUTHOR]

A letter to the editor about granuloma annulare is presented.