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To evaluate whether insertion of self-biodegradable stent into the pylorus to prevent delayed-gastric emptying after pylorus-preserving gastrectomy is feasible and safe through porcine experiment.Self-biodegradable dumbbell-shaped pyloric stents were designed from absorbable suture materials: poly(glycolide-co-caprolactone) (PGCL) or poly-p-dioxanone (PPDO). After gastrotomy on ten pigs, each stent was inserted: two shams, four PGCL stents, and four PPDO stents. Body weight (Bwt), body temperature (BT), complete blood cell (CBC) count, and plain X-ray were evaluated. On postoperative day (POD) 13, euthanasia was performed for histologic evaluation.Operation was successfully performed in all ten pigs. Without tagging suture, both stents migrated before POD 3. The migration was delayed up to POD 13, when the tagging sutures (-t) were applied between stent and stomach wall. Self-degradation of PGCL started from POD 3, and stents were completely excreted from the abdomen by POD 8. Although PPDO were also weakened as self-degradation progressed, its shape was maintained in gastrointestinal tract for 13 days. Unexpected sudden death occurred in the pig with PPDO-t2 on POD 10, which is more likely due to acute volvulus rather than stent-related complication. There was no significant difference between three groups in terms of Bwt, BT, CBC, and histology (sham vs. PGCL vs. PPDO, all p 0.05).The concept of biodegradable stents made of absorbent suture material seems feasible in porcine experiment. Among them, PGCL which has shown rapid absorption, appears to be a more suitable material for transient pyloric absorbable stent when considering safety aspect.

Several studies have previously reported that laparoscopic surgery using an energy sealing device generates hazardous surgical smoke. However, the droplets appearing on the surface of peritoneal fluid irrigated with saline, after dissection phase of laparoscopic gastrectomy were ignored for a long time. This study aimed to investigate the composition and clinical significance of these droplet particles.This study prospectively enrolled 15 patients with early gastric cancer (cT1NanyM0) who were scheduled for laparoscopic gastrectomy. Floating phases of peritoneal irrigation fluid containing droplets in dissected area were retrieved before and after surgical dissection. Using gas chromatography analysis, the areas under the peak were compared between the samples retrieved before and after surgical dissection. We also analyzed if the area value with significant change was related to the inflammatory response.In gas chromatography, the area values after laparoscopic surgical dissection were significantly increased in 10 out of 37 kinds of fatty acids, compared to those before surgical dissection. The significant increase in area value of α-linoleic and eicosadienoic acids were positively correlated with the elevated level of C-reactive protein at postoperative day 2 (Spearman's ρ = 0.843, P 0.001; Spearman's ρ = 0.785, P = 0.001).The lipid droplets, generated after laparoscopic lymphadenectomy during gastric cancer surgery, contained various types of fatty acids, and some of them have been found to be associated with inflammatory response.

Although FDG-PET is widely used in cancer, its role in gastric cancer (GC) is still controversial due to variable [18F]fluorodeoxyglucose ([18F]FDG) uptake. Here, we sought to develop a genetic signature to predict high FDG-avid GC to plan individualized PET and investigate the molecular landscape of GC and its association with glucose metabolic profiles noninvasively evaluated by [18F]FDG-PET. Based on a genetic signature, PETscore, representing [18F]FDG avidity, was developed by imaging data acquired from thirty patient-derived xenografts (PDX). The PETscore was validated by [18F]FDG-PET data and gene expression data of human GC. The PETscore was associated with genomic and transcriptomic profiles of GC using The Cancer Genome Atlas. Five genes, PLS1, PYY, HBQ1, SLC6A5, and NAT16, were identified for the predictive model for [18F]FDG uptake of GC. The PETscore was validated in independent PET data of human GC with qRT-PCR and RNA-sequencing. By applying PETscore on TCGA, a significant association between glucose uptake and tumor mutational burden as well as genomic alterations were identified. Our findings suggest that molecular characteristics are underlying the diverse metabolic profiles of GC. Diverse glucose metabolic profiles may apply to precise diagnostic and therapeutic approaches for GC.

Autonomous polymers that report damage prior to loss of function and simultaneously self-heal are highly relevant for preventing catastrophic failures and extending the lifetimes of materials. Here, we demonstrate mechanochromic and thermally reprocessable thermosets that can be used for autonomic damage reporting and self-healing coatings. A mechanochromic molecule, spiropyran (SP), is covalently incorporated into thermoreversible Diels–Alder (DA) cross-linking networks. Mechanical activation of SPs in DA networks is confirmed by computational simulations and mechanical testing. The damaged areas of the polymers change colour, emit fluorescence signals, and completely recover after heat treatment. Because of the thermoreversible covalent networks, these polymers can be recycled up to fifteen times without degrading their mechanical, damage-reporting, or self-healing properties. Our autonomic material systems provide a new way to enhance the lifespans and reliabilities of thermosetting coatings, which also expands the range for practical applications of force-induced chemical reactions in polymers.

Malnutrition after gastrectomy is associated with a poor prognosis; however, no accurate model for predicting post-gastrectomy malnutrition exists. Hence, we conducted a retrospective study to develop a prediction model identifying gastric cancer patients at high risk of malnutrition after gastrectomy. Gastric cancer patients who underwent curative gastrectomy with more than one weight measurement during a 3-year follow-up period were included. Malnutrition was defined as body mass index (BMI)

Tumor localization during totally laparoscopic gastrectomy is challenging owing to the invisibility of tumors on the serosal surface. We aimed to evaluate the clinical significance of intra-operative gastroscopy in totally laparoscopic partial gastrectomy. We reviewed 1084 gastric cancer patients who underwent either intra- or extracorporeal partial gastrectomy between 2014 and 2018. The intracorporeal group with intra-operative gastroscopy (intra-operative gastroscopy group, n = 187), the intracorporeal group without intra-operative gastroscopy (non-intra-operative gastroscopy group, n = 267), and the extracorporeal group (n = 630) were evaluated for the adequacy of surgical resection margins. We assessed whether total gastrectomy could be avoided according to the performance of intra-operative gastroscopy if the tumor was located within 3–5 cm away from the gastroesophageal junction. The proximal margin positivity was lesser in the intra-operative gastroscopy group than in the non-intra-operative gastroscopy group (0% versus 2.2%; P = 0.045) but similar to that in the extracorporeal group (0% versus 0.6%; P = 0.579). The number of cases with proximal resection margins < 1 cm was lower in the intra-operative gastroscopy group than in the non-intra-operative gastroscopy group (3.7% versus 9.4%; P = 0.025) but comparable with that in the extracorporeal group (3.7% versus 4.1%; P = 0.815). Among 94 patients with lesions located within 3–5 cm apart from the gastroesophageal junction, the intra-operative gastroscopy group (n = 47) had fewer patients who underwent total gastrectomy than the non-intra-operative gastroscopy group (n = 47) (12.8% versus 44.7%; P = 0.001). Intra-operative gastroscopy was the only independent factor that prevented total gastrectomy (P = 0.001). Intra-operative gastroscopy can provide margin safety during intracorporeal partial gastrectomy, avoiding unnecessary total gastrectomy.

Injury to the vagus nerve has been proposed to be associated with occurrence of gallstones after gastrectomy. We investigated the effect of preservation of hepatic branch of the vagus nerve on prevention of gallstones during laparoscopic distal (LDG) and pylorus-preserving gastrectomy (LPPG). Preservation of the vagus nerve was reviewed of cT1N0M0 gastric cancer patients underwent LDG (n = 323) and LPPG (n = 144) during 2016–2017. Presence of gallstones was evaluated by ultrasonography (US) and computed tomography (CT). Incidences of gallstones were compared between the nerve preserved (h-DG, h-PPG) group and sacrificed (s-DG, s-PPG) group. Clinicopathological features were also compared. The 3-year cumulative incidence of gallstones was lower in the h-DG (2.7%, n = 85) than the s-DG (14.6%, n = 238) (p = 0.017) and lower in the h-PPG (1.6%, n = 123) than the s-PPG (12.9%, n = 21) (p = 0.004). Overall postoperative complication rate was similar between the h-DG and s-DG (p = 0.861) as well as between the h-PPG and s-PPG (p = 0.768). The number of retrieved lymph nodes station #1 and 3-year recurrence-free survival were not significantly different between the preserved group and sacrificed group. Injury to the vagus nerve (p = 0.001) and high body mass index (BMI) (≥ 27.5 kg/m2) (p = 0.040) were found to be independent risk factors of gallstone formation in multivariate analysis. Preservation of hepatic branch of the vagus nerve can be recommended for LDG as well as LPPG of early gastric cancer patients to reduce postoperative gallstone formation.

We aimed to investigate the usefulness of near-infrared indocyanine green (ICG)-enhanced fluorescence guidance for infrapyloric LN dissection in laparoscopic distal gastrectomy. This study enrolled patients with early gastric cancer scheduled for laparoscopic distal gastrectomy. After intraoperative submucosal injection of ICG (0.1 mg/mL), LN dissection was conducted under near-infrared ICG fluorescence guidance. The operation time, bleeding events during infrapyloric LN dissection were analyzed. Cases were retrospectively 1:3 propensity-score matched to patients who underwent laparoscopic distal gastrectomy without ICG injection. The mean time from midline omentectomy to exposure of the right gastroepiploic vein was significantly shorter in the ICG group (n = 20) than in the non-ICG group (n = 60) (13.05 ± 5.77 vs 18.68 ± 7.92 min; p = 0.001), and the incidence of bleeding during infrapyloric LN dissection was lower in the ICG group (20% vs 68.3%, p

Isolator flows downstream of the scoop model inlet were visualized by using a planar laser Rayleigh scattering imaging technique. The scoop model was designed for a cruise Mach number of 6. The isolator flows were visualized for two contraction ratios of the scoop inlet (4 and 5) and various freestream Reynolds number conditions. Two freestream Mach numbers were tested to study the flows at the on-design (Mach number 6) and off-design (Mach number 4.5) conditions. Pseudo-cross-sectional flow structures of the isolator were constructed by using averaged planar images from multiple planar imaging planes. The flow visualization found that there exist curved shockwaves and localized flow separation, and three-dimensional shockwave–boundary layer interaction occurs locally affecting boundary layer growth. The visualization showed that Reynolds number determines the thickness of the boundary layer and the size of eddies. Similar overall flow and shockwave structures were observed for different freestream Mach number and Reynolds number conditions. Differences in shockwave angles, impinging shock location, the size of the core flow, and the size of the flow structure were discussed for various flow conditions.

We prepared, for the first time, carbon aerogels support on Pd–WO3 nanorods (CAs/Pd–WO3) hybrid nanocomposite via sol-gel and microwave-assisted methods. The as-prepared CAs/Pd–WO3-modified electrode was used as effective electrocatalyst for nanomolar level detection of mesalazine (MSA). The typical porous nature of carbon aerogels effectively prevented the aggregation of Pd-doped WO3 nanorods and increased the electrochemically active surface area. In addition, the Pd–WO3 nanointerface provides intrinsic improvement of the electrocatalytic activity and stability for the electrochemical oxidation process, and the interconnected conducting network of the porous surfaces of CAs accelerated rapid electron transport at the working electrode. The synergistic effect of the CAs/Pd–WO3 architecture has excellent electrocatalytic activity for the detection of MSA with high sensitivity of 2.403 ± 0.004 μA μM−1 cm−2, low detection limit of 0.8 ± 0.3 nM and wide linear response from 0.003–350 μM at a low applied potential of 0.30 V vs. Ag|AgCl. Satisfactory results were observed for its analytical performance in detecting MSA in human blood serum and urine samples, and recoveries ranged from 98.8 to 100.4%. We believe that the architecture of the modified CAs/Pd–WO3 electrocatalysts can be effectively used in clinical applications for the detection of MSA.

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 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.

In addition to their differentiation potential, self-renewal capability is an important characteristic of stem cells. The limited self-renewal activity of mesenchymal stem cells is the greatest obstacle to the application of stem cell therapy in regenerative medicine. The human TERT gene enhances the self-renewal of MSCs, but the mechanism of self-renewal and the interactions among TERT-gene-related molecules remain unknown. The objectives of this study were to generate immortalized MSCs derived from MSCs isolated from placenta (naive) by human TERT gene transfection with the AMAXA gene delivery system, to compare their characteristics, and to investigate whether increased TERT expression affected the pituitary tumor transforming gene (PTTG1; also known as securin), which is involved in chromosome segregation during mitosis. TERT-immortalized cells (TERT+) with a prolonged life span displayed high PTTG1 expression. TERT+ cells also retained the stemness capacity and multipotency of naive cells and displayed high PTTG1 expression. However, down-regulation of PTTG1 by treatment with short interfering RNA induced cell senescence and decreased telomerase activity. Moreover, TERT bound to PTTG1 formed complexes with chaperones such as Ku70 and heat shock protein 90. Thus, placental MSCs immortalized by TERT gene transfection display differentiation potential and exhibit enhanced self-renewal through a balanced interaction of PTTG1 and chaperones. The interaction between TERT and PTTG1 by association of Ku70 might be important for the enhancement of the limited self-renewal activity of MSCs and for understanding the regulatory mechanisms of self-renewal.

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.

Purpose In this paper, we investigated the influence of orientation and activation area of extended cortical current sources upon the solutions of magnetoencephalography (MEG) inverse problems.

The surfaces of the polyimide films Kapton-E and Upilex-S are modified by ethylenediamine treatment to improve its adhesion to a subsequently deposited copper layer. The changes in the chemical composition, morphology, and adhesion properties of the modified polyimide surface are characterized by X-ray photoelectron spectroscopy, atomic force microscopy, and the 90o peel test. An ethylenediamine polyimide treatment induces amino group formation from the broken imide group. The peel strength of Kapton-E and Upilex-S with a copper layer increases from 0.3 to 0.65 kgf/cm and 0.25 to 0.46 kgf/cm, respectively. The results show that ethylenediamine treatment is a good modification method to greatly increase the adhesion performance of polyimide films to a copper layer. Open image in new window

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.

We present density functional theory (DFT) and complete basis set (CBS) calculations of the prototypical radical–radical reaction of ground–state atomic oxygen [O(3P)] with ethyl (C2H5) radicals. The respective reaction mechanisms and dynamics were investigated on the doublet potential energy surfaces using the DFT method and CBS model. In the title reaction, the barrierless addition of O(3P) to C2H5 led to the formation of energy-rich intermediates that underwent subsequent isomerization and decomposition to yield various products. The products predicted to be found were: H2CO + CH3, CH3CHO + H, c–CH2OCH2 + H, 1,3CH3COH + H, 1,3HCOH + CH3, CH2CHOH + H, C2H3 + H2O, and CH2CH2 + OH. In particular, unlike previous kinetic results, proposed to proceed only through the direct H-atom abstraction process, two distinctive pathways to the formation of CH2CH2 + OH were predicted to be in competition: direct, barrierless H-atom abstraction mechanism versus addition process. The competition was consistent with the recent crossed-beam investigations, and their microscopic dynamic characteristics are discussed at the molecular level.

A new, sulfonated poly(arylene ether sulfone) ionomer with partially fluorinated groups (F-SPAES) was synthesized by the direct polymerization of 1,6-bis(4-fluororphenyl)-perfluorohexane (FPPFH) and 6F-bisphenol A (6F-BPA) with 3,3′-disulfonated 4,4′-difluorodiphenyl sulfone (SDFDPS). The effect of fluorination on the membrane properties and membrane-electrode assembly (MEA) performance for DMFC applications were investigated comprehensively and compared with the pristine SPAES sample. Deliberate control of the hydrophobicity as well as the degree of sulfonation in the F-SPAES membranes allows the effective suppression of water uptake and methanol permeability, while barely affecting the proton conductivity and IEC value. Such an improvement in the membrane properties contributes to the superior single cell performance of the F-SPAES compared to pristine SPAES and Nafion®.

The aim was to evaluate the pretreatment efficacy of endorectal coil (ERC) MRI in accurately predicting extracapsular extension in a group of intermediate risk patients. A total of 40 intermediate risk patients were identified who underwent pretreatment ERC MRI and subsequent radical prostatectomy (RP). Imaging studies and pathologic analysis were compared with respect to presence of extracapsular extension (ECE), involvement of seminal vesicles, and appearance of regional nodes. Mean age was 62 years, PSA 14.8, and most common stage was cT2a/pT2c and Gleason 6. ERC MRI has a positive predictive value of 81%, specificity 89%, and odds ratio 6.47 in determining extracapsular extension. Conversely, its sensitivity is only 43%, with a negative predictive value of 59%. ERC MRI may be useful as an adjunctive study for intermediate risk patients due to its high specificity and positive predictive value, thereby adding information to the clinical decision-making process.

This study examined the bronchodilating effects of 0.6 MAC and 1.1 MAC isoflurane (ISF) on respiratory system resistance (Rrs) following tracheal intubation and determined whether albuterol supplements that effect.Sixty-seven adult patients were anaesthetized with 2 micrograms.kg-1 fentanyl and 5 mg.kg-1 thiopentone and their tracheas intubated following administration of 1 mg.kg-1 succinylcholine. Respiratory system resistance was measured following intubation and the patients then randomized to receive either 1.1 MAC ISF in oxygen or 0.6 MAC ISF in 50% nitrous oxide and oxygen. Ten minutes later, Rrs was again measured. Patients were then further randomized to receive albuterol or a placebo using incremental doses of 2, 5, and 10 puffs (albuterol puff = 90 micrograms) delivered via a metered dose inhaler at ten minute intervals.Isoflurane at 1.1 MAC decreased post-intubation Rrs by 23 +/- 5% (mean +/- sem) whereas the decrease was only 7 +/- 5% for 0.6 MAC ISF (P0.01). Two puffs of albuterol resulted in a further decrease of 12 +/- 3% (mean +/- sem) in Rrs compared with a 2 +/- 4% decrease in the placebo groups (P0.05). Additional puffs of albuterol resulted in no further changes in Rrs.We conclude that following tracheal intubation the reduction in Rrs produced by ISF is highly concentration dependent. Albuterol results in a small further reduction in Rrs.