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Abstract: Various attempts have been made to develop three-dimensional (3-D) cell culture methods because 3-D cells mimic the structures and functional properties of real tissue compared with those of monolayer cultures. Here, we report on a highly simple and efficient 3-D spheroid generation method based on a magnetic pin-array system to concentrate magnetic nanoparticle-incorporated cells in a focal direction. This system was comprised only of external magnets and magnetically induced iron pins to generate a concentrated magnetic field for attracting cells in a focused direction. 3-D spheroid generation was achieved simply by adding magnetic nanoparticle-incorporated cells into a well and covering the plate with a magnetic lid. Cell clustering occurred rapidly within 5 min and created more compact cells with time through the focused magnetic force. This system ensured not only reproducible and size-controlled generation of spheroids but also versatile types of spheroids such as random mixed, core–shell, and fused spheroids, providing a very useful tool for various biological applications. [Copyright &y& Elsevier]

In this study, we propose a new cortical source imaging algorithm for integrating simultaneously recorded electroencephalography (EEG) and magnetoencephalography (MEG), which takes into account the different sensitivity characteristics of the two modalities with respect to cortical source orientations. It is generally accepted that MEG can record neuronal electrical activities with higher spatial resolution than EEG because magnetic field is less affected by the inhomogeneous conductivity profile of the human head than electric field. Nevertheless, it is also well known that MEG cannot reliably detect neuronal sources with radial orientation, whereas EEG is relatively less dependent on the source orientations than MEG. However, this intrinsic difference has not previously been taken into account in the integrative cortical source imaging using simultaneously recorded EEG and MEG data. To consider the different directional sensitivities of the two modalities, we conceptually decomposed the sensor and source spaces into radial and tangential components and developed an explicit formulation described as a general type of weighted minimum norm estimation. Using extensive computer simulations, we demonstrated that our proposed algorithm substantially enhances localization accuracy over almost the entire cortical surface compared to that of the conventional integration algorithm and results in a significant improvement especially when either a radial or tangential source component is dominant. [ABSTRACT FROM AUTHOR]

Highlights: [•] We analyzed the effect of VCA on proliferation and invasion in trophoblast. [•] Cell proliferations of trophoblast were increased at low concentration of VCA. [•] Low concentration of VCA increases MMP-2 expression in trophoblast. [•] The expressions of integrin subunits α5 and β1 were increased at 10pg/ml of VCA. [•] VCA promotes invasion ability of trophoblast via the Akt signaling. [Copyright &y& Elsevier]

Mesenchymal stem cells (MSCs) have great potential for cell therapy in regenerative medicine, including liver disease. Even though ongoing research is dedicated to the goal of bringing MSCs to clinical applications, further understanding of the complex underlying mechanisms is required. Autophagy, a type II programmed cell death, controls cellular recycling through the lysosomal system in damaged cells or tissues. However, it is still unknown whether MSCs can trigger autophagy to enhance regeneration and/or to provide a therapeutic effect as cellular survival promoters. We therefore investigated autophagy's activation in carbon tetrachloride (CCl4)-injured rat liver following transplantation with chorionic plate-derived MSCs (CP-MSCs) isolated from placenta. The expression markers for apoptosis, autophagy, cell survival, and liver regeneration were analyzed. Whereas caspase 3/7 activities were reduced ( p < .05), the expression levels of hypoxia-inducible factor-1α (HIF-1α) and factors for autophagy, survival, and regeneration were significantly increased by CP-MSCs transplantation. Decreased necrotic cells ( p < .05) and increased autophagic signals ( p < .005) were observed in CCl4-treated primary rat hepatocytes during in vitro coculture with CP-MSCs. Furthermore, the upregulation of HIF-1α promotes the regeneration of damaged hepatic cells through an autophagic mechanism marked by increased levels of light chain 3 II (LC 3II). These results suggest that the administration of CP-MSCs promotes repair by systemically concomitant mechanisms involving HIF-1α and autophagy. These findings provide further understanding of the mechanisms involved in these processes and will help develop new cell-based therapeutic strategies for regenerative medicine in liver disease. S TEM C ells 2013;31:1584-1596 [ABSTRACT FROM AUTHOR]

To date, most EEG-based brain-computer interface (BCI) studies have focused only on enhancing BCI performance in such areas as classification accuracy and information transfer rate. In practice, however, test-retest reliability of the developed BCI systems must also be considered for use in long-term, daily life applications. One factor that can affect the reliability of BCI systems is the slight displacement of EEG electrode locations that often occurs due to the removal and reattachment of recording electrodes. The aim of this study was to evaluate and compare various feature extraction methods for motor-imagery-based BCI in terms of robustness to slight changes in electrode locations. To this end, EEG signals were recorded from three reference electrodes (Fz, C3, and C4) and from six additional electrodes located close to the reference electrodes with a 1-cm inter-electrode distance. Eight healthy participants underwent 180 trials of left- and right-hand motor imagery tasks. The performance of four different feature extraction methods [power spectral density (PSD), phase locking value (PLV), a combination of PSD and PLV, and cross-correlation (CC)] were evaluated using five-fold cross-validation and linear discriminant analysis, in terms of robustness to electrode location changes as well as regarding absolute classification accuracy. The quantitative evaluation results demonstrated that the use of either PSD- or CC-based features led to higher classification accuracy than the use of PLV-based features, while PSD-based features showed much higher sensitivity to changes in EEG electrode location than CC- or PLV-based features. Our results suggest that CC can be used as a promising feature extraction method in motor-imagery-based BCI studies, since it provides high classification accuracy along with being little affected by slight changes in the EEG electrode locations. [ABSTRACT FROM AUTHOR]

A modified Nafion binder using a different dispersion solvent, dimethylacetamide (DMAc), was applied to an electrode for a unitized regenerative fuel cell (URFC). The properties of the new Nafion binder, such as dissolution rate, proton conductivity, water uptake, and I- V curves, were characterized in the study. The new Nafion binder showed less brittleness, leading to good structural integrity in the electrode and improvement of stability in the URFC performance. SEM images showed that the interfacial adhesion between the membrane and the electrode was improved by using the new Nafion binder. Therefore, the new Nafion binder was suggested as a promising candidate for a binding material in the electrode of the URFC. [ABSTRACT FROM AUTHOR]

For solving electroencephalographic forward problem, coupled method of finite element method (FEM) and fast moving least square reproducing kernel method (FMLSRKM) which is a kind of meshfree method is proposed. Current source modeling for FEM is complicated, so source region is analyzed usingmeshfreemethod. First order of shape function is used for FEM and second order for FMLSRKM because FMLSRKM adopts point collocation scheme. Suggested method is tested using simple equation using 1-, 2-, and 3-dimensional models, and error tendency according to node distance is studied. In addition, electroencephalographic forward problem is solved using spherical head model. Proposed hybrid method can produce well-approximated solution. [ABSTRACT FROM AUTHOR]

The oxidation reaction dynamics of ethyl radicals (C2H5) in the gas phase are investigated by applying a combination of high-resolution laser induced fluorescence spectroscopy in a crossed-beam configuration and ab initiotheoretical calculations. The supersonic atomic oxygen (O(3P)) and ethyl (C2H5) reactants are produced by photodissociation of NO2and supersonic flash pyrolysis of a synthesized precursor (azoethane), respectively. An exothermic channel leading to the C2H5+ OH (X2Π: ″ = 0, 1) products is identified. The nascent rovibrational state distributions of the OH product show substantial bimodal internal excitations consisting of low- and high-N″ components with neither spin–orbit nor Λ-doublet propensities in the ground and first excited vibrational states. The averaged vibrational population (P″), partitioning with respect to the low-N″ components of the ″ = 0 level, shows a comparable population ratio of P0P1= 1 1.06. On the basis of comparison between the population analyses using ab initioand priorstatistical calculations, the title atom–radical reactive scattering processes are governed by dynamic characteristics. The reaction mechanism can be rationalized by two competing mechanisms: abstraction versusaddition. The major low N″-components can be described in terms of the direct abstraction process responsible for the comparable vibrational populations, while the minor but hot rotational distribution of the high N″-components implies that some fraction of radical reactants is sampled to proceed through the short-lived addition-complex forming process. [ABSTRACT FROM AUTHOR]

Abstract: Nanocomposites of PtRu nanoparticles and polyaniline (an electronically conducting polymer) were synthesized by the borohydride reduction method in an aqueous solution for the anode electrode in direct methanol fuel cells (DMFCs). Due to the high electronic conductivity of polyaniline, the methanol oxidation current for polyaniline supported PtRu nanocomposites was similar to that of carbon supported PtRu catalysts. In addition, Pd-impregnated nanocomposite Nafion membranes were suggested to enhance DMFC performance by blocking or reducing methanol crossover and their characteristics were affected by the impregnation time of Pd-nanoparticles. [Copyright &y& Elsevier]

Abstract: Cu x Fe y V2O5 xerogels were synthesized by doping Cu and Fe into a V2O5 sol via sol–gel process. It retained the desirable layered structure of the V2O5 xerogel. The Cu and Fe doped xerogel cathodes showed high reversibility and their average voltage obtained was about 3.2V versus Li/Li+. Specific capacity of the Cu0.019Fe0.002V2O5 xerogel was more than 150mAh/g at 10mA/g discharge rate in the potential range 2.5–3.9V. After the 30th consecutive cycles, the specific capacity of the Cu0.019Fe0.002V2O5 xerogel electrode maintained 92% of the initial capacity. Impedance analysis revealed that there were two different relaxation processes depending on the equilibrium potentials. [Copyright &y& Elsevier]

Phosphatase of regenerating liver-1 (PRL-1) controls various cellular processes and liver regeneration. However, the roles of PRL-1 in liver regeneration induced by chorionic-plate-derived mesenchymal stem cells (CP-MSCs) transplantation remain unknown. Here, we found that increased PRL-1 expression by CP-MSC transplantation enhanced liver regeneration in a bile duct ligation (BDL) rat model by promoting the migration and proliferation of hepatocytes. Engrafted CP-MSCs promoted liver function via enhanced hepatocyte proliferation through increased PRL-1 expression in vivo and in vitro. Moreover, higher increased expression of PRL-1 regulated CP-MSC migration into BDL-injured rat liver through enhancement of migration-related signals by increasing Rho family proteins. The dual effects of PRL-1 on proliferation of hepatocytes and migration of CP-MSCs were substantially reduced when PRL-1 was silenced with siRNA-PRL-1 treatment. These findings suggest that PRL-1 may serve as a multifunctional enhancer for therapeutic applications of CP-MSC transplantation. [ABSTRACT FROM AUTHOR]

Objective: We investigated the norepinephrine transporter (NET) expression in normal and pre-eclamptic placentas and analyzed the invasion activity of trophoblastic cells based on norepinephrine (NE)-NET regulation. Methods: NET and NE expression levels were examined by western blot and enzyme-linked immunosorbent assay, respectively. Trophoblast invasion activity, depending on NE-NET regulation, was determined by NET-small interfering RNA (siRNA) and NET transfection into the human extravillous trophoblast cells with or without NE treatment and invasion rates were analyzed by zymography and an invasion assay. Results: NET mRNA was expressed at a low level in pre-eclamptic placentas compared with normal placentas and NE concentration in maternal plasma increased significantly in pre-eclamptic women compared to normal pregnant women (p<0.05). NET gene upregulation and NE treatment stimulated trophoblast cell invasion up to 2.5-fold (p<0.05) by stimulating matrix metalloproteinase-9 activity via the phosphoinositol-3-kinase/AKT signaling pathway, whereas NET-siRNA with NE treatment reduced invasion rates. Conclusion: NET expression is reduced by inadequate regulation of NE levels during placental development. This suggests that a complementary balance between NET and NE regulates trophoblast cell invasion activities during placental development.

Background: Pituitary tumor-transforming gene 1 (PTTG1) was recently shown to be involved in the progression as well as the metastasis of cancers. However, their expression and function in the invasion of oral squamous cell carcinoma (SCC) remain unclear. Methods: The expressions of PTTG1 and PTTG1-targeted miRNA in oral SCC cell lines and their invasion capability depended on PTTG1 expression were analyzed by quantitative RT-PCR, Western blots, the transwell insert system and Zymography. Results: Invasion abilities were decreased in oral SCC cells treated with siRNA-PTTG1. When PTTG1 were downregulated in oral SCC cells treated with microRNA-186 and -655 inhibited their invasion abilities via MMP-9 activity. Conclusions: These results indicate that alteration of expression of PTTG1 in oral SCC cells by newly identified microRNA-186 and -655 can regulate invasion activity. Therefore, these data offer new insights into further understanding PTTG1 function in oral SCC and should provide new strategies for diagnostic markers for oral SCC. [ABSTRACT FROM AUTHOR]

Background: Placenta-derived mesenchymal stem cells (PD-MSCs) have been highlighted as an alternative cell therapy agent that has become a next-generation stem cell treatment. Phosphatase of regenerating liver-1 (PRL-1), an immediate early gene, plays a critical role during liver regeneration. Here, we generated enhanced PRL-1 in PD-MSCs (PD-MSCsPRL-1, PRL-1+) using lentiviral and nonviral gene delivery systems and investigated mitochondrial functions by PD-MSCPRL-1 transplantation for hepatic functions in a rat bile duct ligation (BDL) model. Methods: PD-MSCsPRL-1 were generated by lentiviral and nonviral AMAXA gene delivery systems and analyzed for their characteristics and mitochondrial metabolic functions. Liver cirrhosis was induced in Sprague-Dawley (SD) rats using common BDL for 10 days. PKH67+ naïve and PD-MSCsPRL-1 using a nonviral sysyem (2 × 106 cells/animal) were intravenously administered into cirrhotic rats. The animals were sacrificed at 1, 2, 3, and 5 weeks after transplantation and engraftment of stem cells, and histopathological analysis and hepatic mitochondrial functions were performed. Results: PD-MSCsPRL-1 were successfully generated using lentiviral and nonviral AMAXA systems and maintained characteristics similar to those of naïve cells. Compared with naïve cells, PD-MSCsPRL-1 improved respirational metabolic states of mitochondria. In particular, mitochondria in PD-MSCsPRL-1 generated by the nonviral AMAXA system showed a significant increase in the respirational metabolic state, including ATP production and mitochondrial biogenesis (*p < 0.05). Furthermore, transplantation of PD-MSCsPRL-1 using a nonviral AMAXA system promoted engraftment into injured target liver tissues of a rat BDL cirrhotic model and enhanced the metabolism of mitochondria via increased mtDNA and ATP production, thereby improving therapeutic efficacy. Conclusions: Our findings will further our understanding of the therapeutic mechanism of enhanced MSCs and provide useful data for the development of next-generation MSC-based cell therapy and therapeutic strategies for regenerative medicine in liver disease. [ABSTRACT FROM AUTHOR]

Background: Translational studies have explored the therapeutic potential and feasibility of mesenchymal stem cells (MSCs) in several degenerative diseases; however, mechanistic studies of the function of these cells have been insufficient. As ovarian failure causes anovulation as well as ovarian steroid hormonal imbalances, the specific aims of this study were to analyze the therapeutic role of placenta-derived MSCs (PD-MSCs) in an ovarian failure ovariectomy (OVX) rat model and evaluate whether PD-MSC transplantation (Tx) improved folliculogenesis and oocyte maturation in the injured ovary through PI3K/Akt and FOXO signaling. Methods: Blood and ovary tissue were collected and analyzed after various PD-MSC Tx treatments in an ovariectomized rat model. Changes in the expression of folliculogenesis- and ovary regeneration-related genes induced by PD-MSC treatments were analyzed by qRT-PCR, Western blotting, and histological analysis. Results: The levels of hormones related to ovary function were significantly increased in the PD-MSC Tx groups compared with those in the nontransplantation group (NTx). The follicle numbers in the ovarian tissues were increased along with the increased expression of genes related to folliculogenesis in the PD-MSC Tx groups compared with the NTx groups. Furthermore, Tx PD-MSCs induced follicle maturation by increasing the phosphorylation of GSK3 beta and FOXO3 (p < 0.05) and shifting the balance of growth and apoptosis in oocytes. Conclusions: Taken together, these results show that PD-MSC Tx can restore ovarian function and induce ovarian folliculogenesis via the PI3K/Akt and FOXO signaling pathway. [ABSTRACT FROM AUTHOR]

Bed-load discharge of a river can be monitored by indirectly measuring the acoustic pulses generated when the bed load collides with a steel pipe installed on the riverbed (i.e., pipe hydrophone measurement). However, existing methods used for filtering pulses from acoustic signals reflect a combination of bed-load collision frequency bands, thereby limiting characterization capabilities. This study proposes an improved filtering method that separates and efficiently examines frequency bands that are highly correlated with bed-load collision characteristics. Herein, an experimental hydraulic model and bed-load collision sound-measurement system were constructed, and bed-load collision experiments were repeatedly performed for collecting acoustic data using a pipe hydrophone. Fast Fourier Transform analysis was performed on data to select the specific frequency bands and pressures reflecting the bed-load particle size. Furthermore, a bandpass method to examine bed-load collision sounds is also presented herein. Results indicate that in comparison with existing filtering methods, the proposed bandpass method yields higher detection rates under bed-load conditions of low flow rate and small particle size, thereby demonstrating its enhanced effectiveness. [ABSTRACT FROM AUTHOR]

Oxidative stress is one of the major etiologies of ovarian dysfunction, including premature ovarian failure (POF). Previous reports have demonstrated the therapeutic effects of human placenta-derived mesenchymal stem cells (PD-MSCs) in an ovariectomized rat model (OVX). However, their therapeutic mechanism in oxidative stress has not been reported. Therefore, we investigated to profile the exosome of serum and demonstrate the therapeutic effect of PD-MSCs transplantation for the ovary function. We established an OVX model by ovariectomy and PD-MSCs transplantation was conducted by intravenous injection. Additionally, various factors in the exosome were profiled by LC-MS analysis. As a result, the transplanted PD-MSCs were engrafted into the ovary and the existence of antioxidant factors in the exosome. A decreased expression of oxidative stress markers and increased expression of antioxidant markers were shown in the transplantation (Tx) in comparison to the non-transplantation group (NTx) (* p < 0.05). The apoptosis factors were decreased, and ovary function was improved in Tx in comparison to NTx (* p < 0.05). These results suggest that transplanted PD-MSCs restore the ovarian function in an OVX model via upregulated antioxidant factors. These findings offer new insights for further understanding of stem cell therapy for reproductive systems. [ABSTRACT FROM AUTHOR]

Keywords: -amyloid peptides; Alzheimer's disease; nanodepletors; scFv; silica nanostructures EN -amyloid peptides Alzheimer's disease nanodepletors scFv silica nanostructures 1 1 1 04/16/20 20200414 NES 200414 In article number 1910475, Elena A. Rozhkova, Chan Beum Park, Joonseok Lee, and co-workers design A nanodepletors constructed from ultralarge mesoporous silica nanostructures and anti-A single chain variable fragments, which effectively capture monomeric A peptides, inhibit A aggregate formation, and attenuate A -mediated cytotoxicity. The A -targeting and clearing capabilities of the A nanodepletors allow drastic reduction of the number of A plaques in vivo, presenting high therapeutic potential towards Alzheimer's disease treatments. -amyloid peptides, Alzheimer's disease, nanodepletors, scFv, silica nanostructures. [Extracted from the article]

A PtRu-WO[sub 3] nanostructured alloy electrode consisting of alloy nanophases and amorphous tungsten oxide for use in thin-film fuel cells was designed and fabricated using a multigun sputtering system with Pt and Ru metal and a tungsten oxide target. Alloy formation and the presence of nanophases in an amorphous tungsten oxide phase was confirmed by x-ray diffraction and transmission electron microscopy, respectively. The nanostructured alloy electrode, PtRu-W[sub 3] showed the best performance in methanol electro-oxidation because of the presence of the alloy nanophases when compared to a Pt and PtRu thin-film electrode. [ABSTRACT FROM AUTHOR]

B Results: b 3869 patients visited the department of oncology with gastric cancer from 2013 to 2017, 1155 patients were diagnosed with stage IV gastric cancer and 23 Patients underwent conversion surgery. 13 Patients were considered as the early conversion surgery group and 10 patients were defined as the late conversion surgery group. B Conclusions: b This retrospective analysis suggests that in the setting of conversion surgery for stage IV gastric cancer, longer chemotherapy and later operation (after reaching resectability) resulted in better survival outcomes than early operation. [Extracted from the article]

B Background: b Delta-shape anastomosis technique enabled totally laparoscopic pylorus-preserving gastrectomy (TLPPG) in early gastric cancer (EGC) located in the middle of stomach. Instead of the conventional Delta-shape anastomosis using the posterior wall of the proximal remnant stomach for anastomosis, we used anterior wall of the proximal remnant stomach and made anastomosis with posterior wall of the remnant antrum. [Extracted from the article]

B Background: b This study aimed to investigate the usefulness of near-infrared (NIR) imaging with indocyanine green (ICG)-enhanced fluorescence for infrapyloric lymph node (LN) dissection during laparoscopic distal gastrectomy. B Conclusions b : NIR imaging with ICG fluorescence technique can provide a safer and faster infrapyloric lymph node dissection in laparoscopic distal gastrectomy. [Extracted from the article]

Korean mistletoe (Viscum album L. var. coloratum) lectin (VCA) is known as an anticancer drug. However, it is not clear whether VCA affects the self-renewal activity of mesenchymal stem cells (MSCs). Therefore, the objectives of this study were to analyze the effect of VCA on the proliferation of MSCs and expression of stemness markers. We also evaluated the usefulness of placenta-derived MSCs (PD-MSCs) as a screening tool. VCA was stably administered to MSCs, and analyzed self-renewal activities. The effect of IL-6 signaling on MSC proliferation was explored by quantitative methylation-specific PCR (qMSP) and western blot analysis. Compared with the control condition, low concentrations of VCA (10 pg/mL) induced an increase in the self-renewal activity of MSCs. Interestingly, a low concentration of VCA promoted IL-6 signaling in PD-MSCs through altered IL-6/STAT3 gene methylation. Furthermore, inhibition of IL-6 expression in PD-MSCs using an anti-IL-6 antibody caused a decrease in their self-renewal activity through IL-6/STAT3 signaling by altering IL-6/STAT3 gene methylation. These findings provide helpful data for understanding the mechanism of MSC self-renewal via VCA and show that VCA may be useful as a functional natural product for developing efficient therapies using placenta-derived stem cells. [ABSTRACT FROM AUTHOR]