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Electronics that degrade after stable operation for a desired operating time, called transient electronics, are of great interest in many fields, including biomedical implants, secure memory devices, and environmental sensors. Thus, the development of transient materials is critical for the advancement of transient electronics and their applications. However, previous reports have mostly relied on achieving transience in aqueous solutions, where the transience time is largely predetermined based on the materials initially selected at the beginning of the fabrication. Therefore, accurate control of the transience time is difficult, thereby limiting their application. In this work, we demonstrate transient electronics based on a water-soluble poly(vinyl alcohol) (PVA) substrate on which carbon nanotube (CNT)-based field-effect transistors were fabricated. We regulated the structural parameters of the PVA substrate using a three-dimensional (3D) printer to accurately control and program the transience time of the PVA substrate in water. The 3D printing technology can produce complex objects directly, thus enabling the efficient fabrication of a transient substrate with a prescribed and controlled transience time. In addition, the 3D printer was used to develop a facile method for the selective and partial destruction of electronics.

Purpose: To investigate the relationship between topical glaucoma medications and meibomian gland dysfunction (MGD) in early middle-aged patients with glaucoma., Methods: In this cross-sectional study, 50 patients with glaucoma younger than 50 years who had used topical glaucoma medications for more than 6 months and 40 normal controls of similar age were included. Patients in each group were graded for MGD (0-4) using slit-lamp microscopy. Tear film breakup time (BUT), ocular surface staining, and Marx line scores were also evaluated. Differences between both groups were analyzed statistically., Results: The prevalence of MGD was 82% in the group using topical glaucoma medications and 52.5% in the control group. The average period of topical glaucoma medication use was 27.4 months. There were significant differences in the breakup time and Marx line score according to the presence of MGD. Although the duration of topical glaucoma medication use and the severity of MGD did not show a significant correlation, the degree of MGD and the Marx line score were significantly correlated., Conclusions: Glaucoma eye drops may be one factor affecting the eyelid changes associated with MGD. The Marx line score may be used as an index to evaluate MGD in patients with glaucoma.

The utility of a novel ceramic/polymer-composite coating with a micro-textured microstructure that would significantly enhance the functions of biodegradable Mg implants is demonstrated here. To accomplish this, bioactive hydroxyapatite (HA) micro-dots can be created by immersing a Mg implant with a micro-patterned photoresist surface in an aqueous solution containing calcium and phosphate ions. The HA micro-dots can then be surrounded by a flexible poly(l-lactic)-acid (PLLA) polymer using spin coating to form a HA/PLLA micro-textured coating layer. The HA/PLLA micro-textured coating layer showed an excellent corrosion resistance when it was immersed in a simulated body fluid (SBF) solution and good biocompatibility, which was assessed by in vitro cell tests. In addition, the HA/PLLA micro-textured coating layer had high deformation ability, where no apparent changes in the coating layer were observed even after a 5% elongation, which would be unobtainable using HA and PLLA coating layers; furthermore, this allowed the mechanically-strained Mg implant with the HA/PLLA micro-textured coating layer to preserve its excellent corrosion resistance and biocompatibility in vitro., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Herein, the cytocompatibility of selected MAX phases, Ti 3 AlC 2 , Ti 3 SiC 2 , and Ti 2 AlN, were systematically evaluated using in vitro tests for the first time. These phases were anoxic to preosteoblasts and fibroblasts. Compared with the strong viable fibroblasts, the different cellular responses of these materials were clearly distinguishable for the preosteoblasts. Under an osteoblastic environment, Ti 2 AlN exhibited better cell proliferation and differentiation performance than Ti 3 AlC 2 and Ti 3 SiC 2 . Moreover, the performance was superior to that of a commercial Ti-6Al-4V alloy and comparable to that of pure Ti. A possible mechanism was suggested based on the different surface oxidation products, which were determined from the binding energy of adsorbed Ca 2+ ions using first-principles calculations. Compared with the partially oxidized TiC x O y layer on Ti 3 AlC 2 and Ti 3 SiC 2 , the partially oxidized TiN x O y layer on the Ti 2 AlN had a stronger affinity to the Ca 2+ ions, which indicated the good cytocompatibility of Ti 2 AlN.

Porous magnesium (Mg) has recently emerged as a promising biodegradable alternative to biometal for bone ingrowth; however, its low mechanical properties and high corrosion rate in biological environments remain problematic. In this study, porous magnesium was implemented in a scaffold that closely mimics the mechanical properties of human bones with a controlled degradation rate and shows good biocompatibility to match the regeneration rate of bone tissue at the affected site. The alumina-reinforced Mg scaffold was produced by spark plasma sintering and coated with magnesium fluoride (MgF2) using a hydrofluoric acid solution to regulate the corrosion rate under physiological conditions. Sodium chloride granules (NaCl), acting as space holders, were leached out to achieve porous samples (60%) presenting an average pore size of 240 μm with complete pore interconnectivity. When the alumina content increased from 0 to 5 vol%, compressive strength and stiffness rose considerably from 9.5 to 13.8 MPa and from 0.24 to 0.40 GPa, respectively. Moreover, the biological response evaluated by in vitro cell test and blood test of the MgF2-coated porous Mg composite was enhanced with better corrosion resistance compared with that of uncoated counterparts. Consequently, MgF2-coated porous Mg/alumina composites may be applied in load-bearing biodegradable implants., (Copyright © 2016 Elsevier B.V. All rights reserved.)

The introduction of a protective coating layer to highly corrosive magnesium (Mg) has been proposed as one of the common approaches for improved corrosion resistance of Mg-based implants as load-bearing biomedical applications. However, only few studies have focused on the mechanical stability of the coated Mg under practical conditions where significant deformation of the load-bearing implants is induced during the surgical operation or under physiological environments. Therefore, in this study, we developed a dual coating system composed of an interlayer hydroxyapatite (HA) and a top layer poly-L-lactic acid (PLLA) to improve the coating stability under deformation of Mg alloy (WE43) substrate. The HA interlayer was directly formed on the Mg alloy surface, followed by dip-coating of PLLA. As the interlayer, HA improved the adhesion of PLLA by modulating nano- and microscale roughness, in addition to its inherently good bonding strength to Mg. The flexible and deformable top coating PLLA layer mitigated crack propagation in the HA layer under deformation. Thus, the dual coating layer provided good protection to the underlying WE43 from corrosion regardless of deformation. The enhanced corrosion behavior of dual-coated WE43 exhibited better mechanical and biological performance compared to the non-coated or single-coated WE43. Therefore, this dual coating layer on Mg is expected to accelerate Mg-based applications in biomedical devices.

Bacteria can be inactivated through various physical and chemical means, and these have always been the focus of extensive research. To further improve the methodology for these ends, two types of plasma systems were investigated: nano-second pulsed plasma (NPP) as liquid discharge plasma and an Argon gas-feeding dielectric barrier discharge (Ar-DBD) as a form of surface plasma. To understand the sterilizing action of these two different plasma sources, we performed experiments with Staphylococcus aureus (S. aureus) bacteria (wild type) and multidrug resistant bacteria (Penicillum-resistant, Methicillin-resistant and Gentamicin-resistant). We observed that both plasma sources can inactivate both the wild type and multidrug-resistant bacteria to a good extent. Moreover, we observed a change in the surface morphology, gene expression and β-lactamase activity. Furthermore, we used X-ray photoelectron spectroscopy to investigate the variation in functional groups (C-H/C-C, C-OH and C=O) of the peptidoglycan (PG) resulting from exposure to plasma species. To obtain atomic scale insight in the plasma-cell interactions and support our experimental observations, we have performed molecular dynamics simulations to study the effects of plasma species, such as OH, H2O2, O, O3, as well as O2 and H2O, on the dissociation/formation of above mentioned functional groups in PG.

Purpose: To report a novel method for measuring the degree of inferior oblique muscle overaction and to investigate the correlation with other factors., Design: Cross-sectional diagnostic study., Methods: One hundred and forty-two eyes (120 patients) were enrolled in this study. Subjects underwent a full orthoptic examination and photographs were obtained in the cardinal positions of gaze. The images were processed using Photoshop and analyzed using the ImageJ program to measure the degree of inferior oblique muscle overaction. Reproducibility or interobserver variability was assessed by Bland-Altman plots and by calculation of the intraclass correlation coefficient (ICC). The correlation between the degree of inferior oblique muscle overaction and the associated factors was estimated with linear regression analysis., Results: The mean angle of inferior oblique muscle overaction was 17.8 ± 10.1 degrees (range, 1.8-54.1 degrees). The 95% limit of agreement of interobserver variability for the degree of inferior oblique muscle overaction was ±1.76 degrees, and ICC was 0.98. The angle of inferior oblique muscle overaction showed significant correlation with the clinical grading scale (R = 0.549, P < .001) and with hypertropia in the adducted position (R = 0.300, P = .001). The mean angles of inferior oblique muscle overaction classified into grades 1, 2, 3, and 4 according to the clinical grading scale were 10.5 ± 9.1 degrees, 16.8 ± 7.8 degrees, 24.3 ± 8.8 degrees, and 40.0 ± 12.2 degrees, respectively (P < .001)., Conclusions: We describe a new method for measuring the degree of inferior oblique muscle overaction using photographs of the cardinal positions. It has the potential to be a diagnostic tool that measures inferior oblique muscle overaction with minimal observer dependency., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Purpose: To evaluate the diagnostic accuracy of Topcon 3D spectral-domain optical coherence tomography (SD-OCT) for measuring the macular inner retinal layers and the circumpapillary retinal nerve fiber layer (cpRNFL) in order to detect preperimetric glaucoma., Methods: Two hundred four eyes, including 64 healthy eyes, 68 eyes with preperimetric glaucoma, and 72 eyes with early glaucoma were analyzed. Patients had a comprehensive ocular examination including visual field testing and SD-OCT imaging (3D OCT-2000; Topcon Corporation, Tokyo, Japan) in the macular and peripapillary regions. OCT macular scans were segmented into the macular nerve fiber layer (mNFL), ganglion cell layer with the inner plexiform layer (GCIP), and ganglion cell complex (GCC) (composed of the mNFL and GCIP). Ability to discriminate preperimetric glaucoma was assessed using the area under the receiver operating curve for all macular parameters and the cpRNFL., Results: The median visual field MD was -0.78 ± 1.19 dB for the healthy group, -1.02 ± 1.29 dB for the preperimetric glaucoma group, and -3.08 ± 1.61 dB for the early glaucoma group. There were significant differences between the preperimetric and healthy groups for GCIP and GCC and for almost all cpRNFL thickness parameters (P < 0.05), except for the mNFL and cpRNFL (nasal, 3, 4, 8, 9, and 10 o'clock sectors). The comparisons among the AUCs of the cpRNFL parameters (0.772), the GCIP parameters (0.727) and the GCC parameters (0.720) showed no significant differences in their abilities to detect preperimetric glaucoma., Conclusions: The capacity of Topcon 3D-OCT macular intraretinal parameters (GCIP and GCC measurements, not mNFL measurements) to diagnose preperimetric glaucoma is similar to that of the cpRNFL.

Magnesium and its alloys are candidate materials for biodegradable implants; however, excessively rapid corrosion behavior restricts their practical uses in biological systems. For such applications, surface modification is essential, and the use of anticorrosion coatings is considered as a promising avenue. In this study, we coated Mg with hydroxyapatite (HA) in an aqueous solution containing calcium and phosphate sources to improve its in vitro and in vivo biocorrosion resistance, biocompatibility and bone response. A layer of needle-shaped HA crystals was created uniformly on the Mg substrate even when the Mg sample had a complex shape of a screw. In addition, a dense HA-stratum between this layer and the Mg substrate was formed. This HA-coating layer remarkably reduced the corrosion rate of the Mg tested in a simulated body fluid. Moreover, the biological response, including cell attachment, proliferation and differentiation, of the HA-coated samples was enhanced considerably compared to samples without a coating layer. The preliminary in vivo experiments also showed that the biocorrosion of the Mg implant was significantly retarded by HA coating, which resulted in good mechanical stability. In addition, in the case of the HA-coated implants, biodegradation was mitigated, particularly over the first 6 weeks of implantation. This considerably promoted bone growth at the interface between the implant and bone. These results confirmed that HA-coated Mg is a promising material for biomedical implant applications., (© 2013 Wiley Periodicals, Inc.)

Pyruvate kinase, muscle type 2 (PKM2), is a key factor in the aerobic glycolysis of cancer cells. In our experiments, liver cancer cell lines exhibited a range of sensitivity to PKM2 knockdown-mediated growth inhibition. We speculated that this differential sensitivity is attributable to the variable dependency on glycolysis for the growth of different cell lines. Transcriptome data revealed overexpression of a glucose transporter (GLUT3) and a lactate transporter (MCT4) genes in PKM2 knockdown-sensitive cells. PKM2 knockdown-resistant cells expressed high levels of the lactate dehydrogenase B (LDHB) and glycine decarboxylase (GLDC) genes. Concordant with the gene expression results, PKM2 knockdown-sensitive cells generated high levels of lactate. In addition, ATP production was significantly reduced in the PKM2 knockdown-sensitive cells treated with a glucose analog, indicative of dependency of their cellular energetics on lactate-producing glycolysis. The PKM2 knockdown-resistant cells were further subdivided into less glycolytic and more (glycolysis branch pathway-dependent) glycolytic groups. Our findings collectively support the utility of PKM2 as a therapeutic target for high lactate-producing glycolytic hepatocellular carcinoma (HCC).

Aims: The involvement of cytokines in the aqueous humour is important in the development and progression of diabetic macular oedema (DMO) and macular oedema (MO) due to branch retinal vein occlusion (BRVO-MO). In this study, the concentrations of cytokines in the aqueous humour of eyes with DMO and BRVO-MO were measured and compared., Methods: Prospective, observational case series. Aqueous samples were obtained from 18 eyes with DMO (DMO group), 12 eyes with BRVO-MO (BRVO-MO group), and 16 normal eyes (control group). The aqueous levels of cytokines, including interleukin (IL)-2, IL-5, IL-6, IL-8, IL-12p70, IL-13, monocytochemotactic protein-1 (MCP-1), macrophage inflammatory protein-1α (MIP-1α), platelet-derived growth factor-AA (PDGF)-AA, transforming growth factor-α (TGF-α), interferon-γ (IFN-γ), epidermal growth factor, fibroblast growth factor 2 (FGF2) and vascular endothelial growth factor (VEGF), were measured., Results: The aqueous levels of IL-8, MCP-1, PDGF-AA and VEGF were higher, and IL-13 was lower in the DMO group compared with the control group. The aqueous levels of IL-8 and VEGF were higher in the BRVO-MO group than in the control group. Compared with the IL-6 and MCP-1 levels in the BRVO-MO group, those levels were significantly higher in the DMO group. Correlation analyses revealed that IL-8 was positively and IFN-γ was negatively correlated with the severity of MO in the DMO group. In the BRVO-MO group, IL-8 and was positively correlated with severity of MO and retinal ischaemia., Conclusions: DMO and BRVO-MO may differ in terms of pathogenesis because the cytokine concentrations in the aqueous humour differ. The results suggest that the inflammatory reaction may be more activated in DMO than in BRVO-MO, and ischaemic insult may play a central role in the development of BRVO-MO.

Spontaneous intrahepatic bleeding is a rare condition. In the absence of trauma, intrahepatic hematoma may be due to underlying liver disease. We report a case of hepatocellular carcinoma in the patient who had huge intrahepatic hematoma without definite intrahepatic tumor at the time of initial presentation. A 54-year-old man was admitted to our hospital with a sudden onset of upper abdominal pain. Initial abdominal CT scan showed huge hematoma measuring more than 13 cm in diameter in the right lobe of the liver. However, there was no enhancing lesion in the liver. Laboratory data showed high alanine aminotransferase, alpha-fetoprotein and positive HBsAg. The MRI and angiography could not also depict any mass in the liver. The patient was treated with percutaneous drainage on the intrahepatic hematoma. The cytology from drainaged blood revealed no malignant cell. After hematoma decreased, follow-up CT scan depicted an enhancing tumor in the liver. He underwent right hepatic lobectomy and histopathological examination showed hepatocellular carcinoma.