Search

To the best of our knowledge there have been no randomized controlled trials comparing lobectomy—a standard treatment for patients with early-stage non-small cell lung cancer (NSCLC)—and particle beam therapy (PBT), the best performing existing radiotherapy. We conducted a virtual randomized trial in medically operable patients with stage IA NSCLC to compare lobectomy and PBT effectiveness. A Markov model was developed to predict life expectancy after lobectomy and PBT in a cohort of patients with stage IA NSCLC. Ten thousand virtual patients were randomly assigned to each group. Sensitivity analyses were performed as model variables and scenarios changed to determine which treatment strategy was best for improving life expectancy. All estimated model parameters were determined using variables extracted from a systematic literature review of previously published articles. The preferred strategy differed depending on patient age. In young patients, lobectomy showed better life expectancy than that of PBT. The difference in life expectancy between lobectomy and PBT was statistically insignificant in older patients. Our model predicted lobectomy as the preferred strategy when operative mortality was under 5%. However, the preferred strategy changed to PBT if operative mortality post lobectomy was over 5%. For medically operable patients with stage IA NSCLC, our Markov model revealed the preferred strategy of lobectomy or PBT regarding operative mortality changed with varying age and comorbidity. Until randomized controlled trial results become available, we hope the current results will provide a rationale background for clinicians to decide treatment modalities for patients with stage IA NSCLC.

Combination of MEK inhibitor and 5-FU had showed limited efficacy in clinical trials. We previously reported that acquired resistance to 5-FU was related with continued activation of salvage pathway. Here we investigated whether combination of 5-FU and a MEK inhibitor had treatment sequence-dependent synergistic effects in KRAS or BRAF mutant colon cancer models. Treatment with 5-FU followed by selumetinib (FS) induced highest cell death and synergy compared with reverse (SF) and concomitant (cFS) treatment in six cell lines. SF or cFS combination induced synergy in 1 or 2 cell lines, respectively, in which the synergy was less than that by FS combination. FS enhanced apoptosis and decreased anchorage-independent growth. Induction of thymidine kinase 1, a rate-limiting enzyme in salvage pathway, by 5-FU was abrogated by subsequent treatment with selumetinib, and ERK reactivation after selumetinib was prohibited by pretreatment with 5-FU. FS altered mRNA expression in groups of genes distinct from SF. Administration of 5-FU (10 or 30 mg/kg/day) for 7 days, followed by selumetinib (10 or 25 mg/kg/day) for another 7 days, in colo205 and HCT8 xenograft models significantly decreased tumor growth compared with a single agent. However, co-administration in the reverse sequence did not show the difference in tumor size compared with the treatment of single agent. Decreased expression of Ki67 was observed in tumors from mice treated with FS. Our results suggest that sequential administration of 5-FU plus selumetinib would be a promising strategy for patients having KRAS or BRAF mutant colon cancers.

Humans perform grasping by breaking down the task into a series of action phases, where the transitions between the action phases are based on the comparison between the predicted tactile events and the actual tactile events. The dependency on tactile sensation in grasping allows humans to grasp objects without the need to locate the object precisely, which is a feature desirable in robot grasping to successfully grasp objects when there are uncertainties in localizing the target object. In this paper, we propose a method of implementing a tactile event based grasping algorithm using memorized predicted tactile events as state transition triggers, inspired by the human grasping. First, a simulated robotic manipulator mounted with pressure and vibration sensors on each finger, analogous to the different mechanoreceptors in humans, performed ideal grasping tasks, from which the tactile signals between consecutive states were extracted. The extracted tactile signals were processed and stored as predicted tactile events. Secondly, a grasping algorithm composed of eight discrete states, Reach, Re-Reach, Load, Lift, Hold, Avoid, Place, and Unload was built. The transition between consecutive states is triggered when the actual tactile events match the predicted tactile events, otherwise, triggering the corrective actions. Our algorithm was implemented on an actual robot, equipped with capacitive and piezoelectric transducers on the fingertips. Lastly, grasping experiments were conducted, where the target objects were deliberately misplaced from their expected positions, to investigate the robustness of the tactile event based grasping algorithm to object localization errors.

System xc− contributes to glutathione (GSH) synthesis and protects cells against ferroptosis by importing cystine and exchanging it with glutamate. Transforming growth factor β1 (TGF-β1) induces redox imbalance; however, its role in system xc− regulation remains poorly understood. The present study was the first to show that TGF-β1 repressed the protein and mRNA levels of xCT, a catalytic subunit of system xc−, in PLC/PRF/5, Huh7, Huh6, and HepG2 cells with an early TGF-β1 gene signature but not in SNU387, SNU449, SNU475, and SK-Hep1 cells with a late TGF-β1 gene signature. TGF-β1 treatment for 24 h reduced xCT expression in a dose-dependent manner but this TGF-β1-induced repression was blunted by pretreatment with a TGF-β1 receptor inhibitor. TGF-β1-mediated xCT repression was prevented by Smad3, but not Smad2 or Smad4, knockdown, whereas it was enhanced by Smad3 overexpression. TGF-β1 decreased GSH levels in control cells but not xCT-overexpressed cells. Furthermore, TGF-β1 increased reactive oxygen species (ROS) levels in PLC/PRF/5 cells and enhanced tert-butyl hydroperoxide-induced ROS levels in Huh7 cells; these changes were reversed by xCT overexpression. TGF-β1 treatment ultimately induced the ferrostatin-1- and deferoxamine-dependent lipid peroxidation after 2 days and 8 days in PLC/PRF/5 and Huh7 cells but not in SNU475 and SK-Hep1 cells. Pre-treatment of TGF-β1 for 2 days enhanced the reduction of cell viability induced by RSL3, a GSH peroxidase 4 (GPX4) inhibitor, in PLC/PRF/5 and Huh7 cells. In conclusion, TGF-β1 represses xCT expression via Smad3 activation and enhances lipid peroxidation in hepatocellular carcinoma cells with an early TGF-β1 signature, which would benefit from the targeting of GPX4.

We report a rare case of long-term survival in a patient who received local therapy and salvage chemotherapy for recurrent metastases, along with a literature review. A 65-year-old male patient underwent subtotal gastrectomy for advanced gastric adenocarcinoma. Six months after gastrectomy, 2 metastatic intra-abdominal lymph node enlargements were detected, which were treated with radiotherapy. At 55 months after gastrectomy, an abdominal wall mass was detected, which was treated by surgical resection. The patient received 5-fluorouracil/leucovorin/irinotecan chemotherapy for 27 months before and after radiotherapy and docetaxel chemotherapy for 6 months after surgical resection of the abdominal wall metastasis. At the last visit, 7.8 years since the initial resection of the primary gastric cancer and 6.2 years since detection of the first metastases, the patient was disease-free and required no further chemotherapy. This case suggests that repeated local therapy offers potential for long-term survival in a carefully selected subset of patients with recurrent metastases.

Various 3-D structured Pt/xrGO-yPolyethyleneimine-functionalized MWCNTs (PMWCNT) were successfully prepared by the hybridization of rGO and PMWCNT. The FE-SEM and TEM images confirm the 3-D structure of hybridized Pt/rGO-PMWCNT catalyst and dispersion of Pt nanoparticles. In case of Pt/PMWCNT, Pt nanoparticles are preferentially deposited onto the external surface of PMWCNT but upon hybridization, the preferential deposit of Pt nanoparticles onto PMWCNT is not expected due to high affinity of rGO toward Pt nanoparticles. The Pt content deposited onto the hybridized supporting materials tends to be increased with rGO content. It is noteworthy that the BET surface area is increased with PMWCNT content due to the formation of the 3-D structure. The electrochemical active surface area (ECSA) and durability based on ECSA is also affected by the mass ratio of rGO and PMWCNT, exhibiting the highest ECSA of 32.5 m2/g and the least reduction of ECSA after 1200 cycle by Pt/1rGO-1PMWCNT. The cell performance is enhanced by the hybridization with the best cell performance by Pt/1rGO-1PMWCNT. It is, therefore, desirable to choose the appropriate mass ratio of rGO and PMWCNT to maximize the electrochemical properties.

Dural metastasis from primary gastric adenocarcinoma has been rarely reported, and its prognosis is very poor because it frequently leads to acute subdural hematoma. Here, we describe a case with sequential spinal and cranial dural metastases from gastric adenocarcinoma without subdural hematoma. A 43-year-old woman with gastric adenocarcinoma and well-controlled peritoneal carcinomatosis presented with back pain, right radiating leg pain, left facial palsy, and hearing loss. Magnetic resonance imaging of the spine and brain revealed dural masses at the lumbosacral junction with invasion to the L5 and S1 nerve roots and at the skull base with invasion to the internal auditory canal. She was treated with local radiotherapy, and her pain and neurologic symptoms improved after palliative radiotherapy. This is the first reported case of dural metastases of gastric adenocarcinoma of the spine and skull base but with a relatively indolent course and without subdural hematoma.

The Pt-supported hollow structured Pt-HZrO2 with the shell thickness of 27 nm is successfully synthesized. The water retention ability of Pt-HZrO2 is significantly enhanced compared with that of SiO2@ZrO2 due to the hydrophilic hollow structured HZrO2with high BET surface area. Pt-C and Pt-HZrO2 are combined with different weight fractions to prepare the double catalyst electrode (DCE). The membrane electrode assembly with the DCE is fabricated and applied to both anode and cathode or anode side only. The water flooding and thus rapid voltage drop is affected by the presence/or absence of the DCE at the cathode side. The cell test and visual experiment suggests that the Pt-HZrO2 layer adsorb the water molecules generated by the oxygen reduction reaction (ORR), preventing the water flooding. The power generation under RH 0% strongly suggests the back-diffusion of water molecules generated by the ORR. The flow rate to the cathode significantly affects the water flooding and cell performance. Higher flow rate to the cathode is advantageous to expel the water generated by the ORR, thus preventing water flooding and enhancing the cell performance. Therefore, the weight fraction of Pt-C to Pt-HZrO2 and the flow rate to the cathode should be well balanced.

A high-performance Pt-C/Pt-TiO2 dual-catalyst electrode was prepared and found to exhibit excellent water production and retention in self-humidifying proton-exchange membrane fuel cells. Different weight fractions of xPt-C/(1‒x)Pt-TiO2 dual-catalyst layer were applied to both anode and cathode with fixed total Pt loadings of 0.2 mg/cm2 and 0.3 mg/cm2. The dependence of cell performance on the Pt-TiO2 content in dual-catalyst electrode was highly affected by the relative humidity (RH): When the RH was lower than 60%, the cell performance was significantly affected by the Pt-TiO2 content. The ability to produce and retain water of the Pt-TiO2 catalyst layer on the anode side was very important for the zero-RH cell performance. A visual cell experiment clearly revealed that water production at the anode was highly dependent on the Pt-TiO2 content in the Pt-C/Pt-TiO2 dual layer on the anode side. A half dual-layer experiment involving the Pt-TiO2 on the cathode side alone strongly suggested that zero-RH operation is impracticable. The Pt-TiO2 in the dual layer at the anode produces water consuming the H2 and O2 crossing the membrane from the cathode, resulting in excellent cell performance under zero RH. The Pt-C/Pt-TiO2 ratio must be optimized in terms of the water-production and retention ability.

Strength measures should be normalized by body mass; however, the definition of sarcopenia includes only simple grip strength. Thus, we compared the relationship of grip strength and grip strength divided by body weight or body mass index to two major consequences of sarcopenia, namely metabolic syndrome and poor quality of life. Data from the participants (aged 60 years or older) of the Sixth Korea National Health and Nutrition Examination were analyzed. Metabolic syndrome was defined according to the Adult Treatment Panel III guidelines with some modifications appropriate for Koreans. Quality of life was assessed using the EuroQoL Five-dimension questionnaire. Multiple logistic regression models were used to evaluate the association of grip strength and grip strength divided by body weight with metabolic syndrome and quality of life. A total of 1273 men and 1436 women were included in the analyses. Grip strength was not related to metabolic syndrome, whereas grip strength divided by body weight and grip strength normalized by body mass index revealed a dense dose-response relationship. All measures showed a similar correlation with quality of life. Grip strength divided by body weight can be superior to simple grip strength and grip strength normalized by body mass index in representing the metabolic aspects of sarcopenia.

Various therapeutic effects of mesenchymal stem cells (MSCs) have been reported. However, the rapid clearance of these cells in vivo, difficulties in identifying their therapeutic mechanism of action, and insufficient production levels remain to be resolved. We investigated whether a pioglitazone pre-treatment of MSCs (Pio-MSCs) would stimulate the proliferation of co-cultured tenocytes. Pioglitazone increased the proliferation of MSCs and enhanced the secretion of VEGF (vascular endothelial growth factor) and collagen in these cells. We then examined the effects of Pio-MSCs on tenocytes using an indirect transwell culture system. A significant increase in tenocyte proliferation and cell cycle progression was observed in these co-cultures. Significant increases were observed in wound scratch closure by tenocytes from a Pio-MSC co-culture. Pio-MSCs also enhanced the secretion of collagen from tenocytes. A higher mRNA level of collagen type 1 (Col 1) and type 3 (Col 3), scleraxis (Scx), and tenascin C (TnC) was found in the tenocytes in Pio-MSC co-cultures compared with monocultured cells or tenocytes cultured with non-treated MSCs. Our results indicate that pioglitazone enhances the therapeutic effects of MSCs on tendon repair.

Different levels of B were doped into graphene (Gr), and Pt nanoparticles were subsequently deposited to form Pt-xB-Gr (x = 0.0, 1.0, 3.0, and 5.0). B-doping led to a narrower Pt nanoparticle size distribution with a more uniform dispersion. The amount of Pt deposited onto Gr increased significantly by at least 13% upon B-doping, in comparison to Pt-Gr, and was proportional to the B-doping level. However, X-ray photoelectron spectroscopy and Raman analyses revealed an upper limit to B-doping in the form of BC3 within the graphene structure for x > 3.0 in Pt-xB-Gr. Rotating disk electrode experiments demonstrated an enhancement in the oxygen reduction reaction (ORR) upon B-doping, yielding a maximum ORR activity with Pt-3.0B-Gr. Koutechy-Levich plots estimated an electron transfer number (n) of 2.5, 3.2, 3.6, and 3.0 for Pt-xB-Gr, where x = 0.0, 1.0, 3.0, and 5.0, respectively, based on the diffusion limiting current density. The enhancement in the ORR and cell performance of high temperature proton exchange membrane fuel cells (HT-PEMFCs) upon B-doping was attributed to the transfer of π electrons that were activated through the conjugation of electron deficient B with the inactive π electron system within graphene, to Pt nanoparticles.

Nrf2 (nuclear factor erythroid 2-related factor 2) is an antioxidant transcription factor. AMP-activated protein kinase (AMPK) functions as a central regulator of cell survival in response to stressful stimuli. Nrf2 should be coordinated with the cell survival pathway controlled by AMPK, but so far the mechanistic connections remain undefined. This study investigated the role of AMPK in Nrf2 trafficking and its activity regulation. A subnetwork integrating neighbor molecules suggested direct interaction between AMPK and Nrf2. In cells, AMPK activation caused nuclear accumulation of Nrf2. In the in vitro kinase and peptide competition assays, AMPK phosphorylated Nrf2 at the Ser558 residue (Ser550 in mouse) located in the canonical nuclear export signal. Nrf2 with an S550A mutation failed to be accumulated in the nucleus after AMPK activation. Leptomycin B, a nuclear export inhibitor, did not enhance nuclear accumulation of wild-type Nrf2 (WT-Nrf2) activated by AMPK or a phospho-Ser550-mimetic Nrf2 mutant, corroborating the finding that AMPK facilitated nuclear accumulation of Nrf2, probably by inhibiting nuclear export. Activated glycogen synthase kinase 3β (GSK3β) diminished the basal nuclear level of Myc-S550A-Nrf2. Taking the data collectively, AMPK phosphorylates Nrf2 at the Ser550 residue, which, in conjunction with AMPK-mediated GSK3β inhibition, promotes nuclear accumulation of Nrf2 for antioxidant response element (ARE)-driven gene transactivation.

Pt nanoparticles with about 2 nm are successfully deposited onto ~50 nm commercial TiO2 and various Nafion/xPt–TiO2/(1−x)Graphene oxide composite membranes are prepared. Water uptake of composite membrane is enhanced with GO content by maximum 15.3% due to hydrophilic GO compared to casting Nafion. Ion exchange capacity and proton conductivity are also enhanced with GO content but too much GO incorporation seems to reduce them probably due to the blocking effect by 2-dimensional GO sheets. Hydrophilic TiO2 alone does not seem to exhibit sufficient water retention ability to exert excellent cell performance. The results clearly show that the cell performance under low humidifying condition including zero humidity is significantly affected by retention ability of water formed from Pt sites. Thermogravimetric analysis shows that free water retained by membrane could be increased by 32% with the addition of TiO2 and 45% further with additional GO compared with that of casting Nafion, respectively. The cell performance is significantly enhanced by sinergistic effect upon addition of appropriate amount of Pt–TiO2 and GO to Nafion: that is, at 0.6 V, 1.0 A/cm2 and 0.54 A/cm2 for Nafion/0.8Pt–TiO2/0.2GO, and 0.42 A/cm2 and 0.02 A/cm2 for casting Nafion under 100% RH and 0% RH.

Boron and nitrogen were successfully co-doped into graphene (Gr) nanosheets to which Pt nanoparticles with ∼3.7 nm are uniformly deposited on BCN-Gr. Pt content on BCN-Gr is estimated to be 50 wt.% by TG/DTA analysis. Pt-BCN-Gr is intercalated by different amount of CB (carbon black), and it is designated as Pt-BCN-Gr/CBx (x = 0.0, 0.3, 0.4, 0.5 and 0.6). The membrane electrode assembly is fabricated with commercial Pt-C and Pt-BCN-Gr/CBx as anode and cathode catalysts, respectively. The cell performance is highly consistent with electrochemical active surface area and the best cell performance of 0.54 W/cm 2 in power density is achieved for Pt-BCN-Gr/CB0.5. The results show that positive effect of B and N co-doping on cell performance becomes more significant for lower intercalated CB content. Direct comparison between Pt-BCN-Gr/CB and Pt-Gr/CB clearly exhibits that Pt-BCN-Gr/CB shows better cell performance for Pt-BCN-Gr/CB than Pt-Gr/CB at lower CB content. About 28%–157% in cell performance at 0.6 V has been enhanced by B and N co-doping compared with that of Pt-Gr/CB. The enhancement in cell performance and durability is probably attributed to the synergistic effect by B and N co-doping and intercalation by CB.

Mesoporous carbon molecular sieve, CMK-3 is successfully prepared through the carbonization of hexagonally arrayed mesoporous SBA-15 as a template and Pt nanoparticles are then deposited onto CMK-3. Mesoporous Pt-CB(1 − x )/Pt-CMK-3 x hybrid catalysts ( x = 0.0, 0.4, 0.5, 0.7 and 1.0) are adopted as a cathode catalyst in polymer electrolyte membrane fuel cell for the purpose of enhancing mass transfer and durability. Transmission electron micrograph and X-ray diffraction micrograph analyses show the uniform dispersion of Pt nanoparticles without any distinct agglomeration through the mesopores of CMK-3 with particle size of ∼2.3 nm. X-ray photoelectron spectroscopy analysis confirms the oxidation state of Pt species deposited onto CMK-3. The electrochemical active surface areas (ECSA) obtained by cyclic voltammetry analysis for various Pt-CB(1 − x )/Pt-CMK-3 x are estimated to be 27.4 m 2 g −1 , 38.9 m 2 g −1 , 44.7 m 2 g −1 , 36.9 m 2 g −1 and 30.8 m 2 g −1 for x = 0.0, 0.4, 0.5, 0.7 and 1.0, respectively. The single cell test shows that the cell performance is highly consistent with ECSA: that is, the cell performance of Pt-CB(0.5)/Pt-CMK-3(0.5) is drastically enhanced by 62% and 322% compared with those of Pt-CMK-3 and Pt-CB alone, respectively. The drastic enhancement in cell performance is attributed to synergistic effect of enhanced mass transfer and fairly good Pt utilization. Accelerated durability test shows a drastic enhancement in durability of Pt-CMK-3 and various Pt-CB/Pt-CMK-3 hybrid catalysts compared to that of Pt-CB. The start-up/shut-down cycling test shows that mesoporous CMK-3 could be an excellent candidate for alternative supporting materials to commercial Pt-CB.

Despite the advantages of electromyography (EMG), which can grasp intent before actual movement, there have not been many studies on the use of EMG in exoskeletons. In this paper, we conducted an experiment to analyze the characteristics of electromyography when EMG signals are used in exoskeleton robots. We integrated the advantages of EMG sensors and physical sensors to control exoskeleton robots using EMG signals and physical signals. The walking environment was defined using the surface electromyography (sEMG) signal and the physical signal to an accuracy of 88% or more. To compensate for the limitations of physical sensors, we used sEMG to distinguish changes in the load during walking. Moreover, sEMG signals and physical signals were used to distinguish external collisions and to identify other variables that could be distinguished. Finally, to examine the characteristics of muscular fatigue, which is a disadvantage when using electromyography, we conducted a muscle fatigue experiment in the lower limb and summarized how the EMG characteristics change in relation to the degree of force and the muscle fatigue.

The objective of this study was to investigate the growth performance, physiological and blood parameter responses of beef calves during and after sudden exposure to heat stress condition, compared with calves in thermoneutral conditions. Data were collected from four Korean native calves (BW 136.9 ± 6.23 kg and age 169.6 ± 4.60 d), which were kept at four designated temperature humidity index (THI) levels based on ambient temperature and humidity: Threshold (22 to 24 °C, 60%; THI = 68 to 70), Mild (26 to 28 °C, 60%; THI = 74 to 76), Moderate (29 to 31 °C, 80%; THI = 81 to 83) and Severe (32 to 34 °C, 80%; THI = 88 to 90) stress level. Calves were subjected to ambient temperature (22 °C) for 7 days, after which chamber temperature and humidity were raised to each THI level for 21 days. The blood metabolites were analyzed using biochemical analyzer-TBA-40FR. Physiological parameters of heat stress were measured, including rectal temperature (RT), skin temperature (ST) and heart rate (HR) every three days. Feed and water intake were recorded daily (at 0900), and body weight measured once a week. The results showed that RT (p = 0.001), ST (p = 0.001) and HR (p = 0.001) were significantly increased in the severe stress level compared with the threshold but had no effect on growth performance. Glucose and GOT levels were increased after sudden exposure to heat stress condition; however, as the high temperature condition was maintained, glucose and GOT levels returned to a normal range after 14 days. We suggest that physiological parameters (RT, ST and HR) were important indicators of calves under heat stress. In addition, calves exposed to heat stress had physiological responses that regulated metabolites in the blood, to maintain homeostasis during the long-term heat stress.

Predicting resistance or susceptibility to infectious diseases on the basis of the genotypes of animals regarding disease or immune related genes could be important in animal production. We evaluated the potential influence of the genetic polymorphisms of four immune related genes, porcine beta defensin 4, interferon-induced GTP-binding protein Mx1, natural resistance-associated macrophage protein 1 (Nramp1), and Toll-like receptor 2 (TLR2) on post-weaning piglet survivability in farms. We selected a single SNP that satisfied the criteria of non-synonymous substitutions and the minor allele frequency >0.1 from each gene, and performed PCR–RFLP. Distributions of allele and genotype frequencies of the SNPs were, in general, significantly different among the five breeds (Berkshire, Yorkshire, Duroc, Landrace, and Korean native pigs. Initially, 371 randomly collected Yorkshire × Landrace F1 piglets consisting of post-weaning survival (n = 185) and non-survival groups (n = 186) were genotyped for the selected SNPs. For the Nramp1 and TLR2 SNPs, genotype frequencies were significantly different between the two groups (P

GDEs (gas diffusion electrodes) fabricated with catalyst layer, supporting layer and GDL (gas diffusion layer) are prepared for high temperature polymer electrolyte membrane fuel cell. A supporting layer consisting of different amount of PTFE (polytetrafluorethylene)-bonded carbon black from 0.0 g to 0.2 g is coated onto GDL to prevent Pt loss into GDL and to enhance the intimate contact between catalyst layer and GDL. Various catalyst layers are prepared by different LiCl content in PBI (polybenzimidazole) solution and coated directly on the top of optimized supporting layer. After preparing GDE, LiCl is leached out of the catalyst layer and the pore structure of GDE left behind the leaching is investigated with LiCl content. The N 2 adsorption isotherm indicates that leaching of LiCl from catalyst layer leaves the pores behind and the BET surface area is increased with LiCl content. It is seen that the LiCl content significantly affects the dispersion of Pt nanoparticles in PBI: that is, too low LiCl content leads to non-uniform dispersion of Pt nanoparticles, resulting in poor cell performance. An appropriate amount of LiCl would lead to better cell performance.

In order to enhance the electrochemical properties, especially durability and cell performance in proton exchange membrane fuel cell, electron deficient boron is doped into graphene, followed by deposition of Pt nanoparticles. Successful synthesis of Pt-boron doped graphene (Pt–B–Gr) by pyrolytic process is confirmed by X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy and Transmission electron microscopy analyses. Pt–B–Gr is intercalated by different amount of CB (carbon black) based on Pt–B–Gr/CBx (x = 0.0, 0.2, 0.3, 0.4) and applied to cathode in proton exchange membrane fuel cell. The ECSA (electrochemical active surface area) is increased with CB content up to 30 wt.% of Pt–B–Gr from 21.4 to 33.6 m 2 g −1 beyond which it is rather slightly decreased to 29.6 m 2 g −1 . The ADT (accelerated durability test) is conducted where the ECSA is compared at every 400 cycles up to 1200 cycles for durability. The result exhibits that boron doping into graphene significantly enhances the durability. It might be attributed to more tight binding between Pt and B due to the electron transfer from graphene to boron. The cell performance is enhanced and it is attributed to the combined effect of B-doping and intercalation.

Pt–graphene (Pt–G) is prepared by in-situ reduction of Pt precursor on graphene oxide surface using a microwave method. Various Nafion/xPt–G/ySiO2 composite membranes where x is 0.5 wt%, 1.5 wt% and 3.0 wt% and y is 0.0 wt%, 1.5 wt% and 3.0 wt%, respectively are fabricated of which water uptake and proton conductivity show similar trend: that is, those are increased with both Pt–G and SiO2 contents. The cell performance is significantly affected by relative amount of Pt–G and SiO2 in composite membrane. Below 1.5 wt% in Pt–G content, the cell performance is increased with SiO2 due to the excellent retention ability of SiO2 for water produced from Pt site on graphene. Beyond 1.5 wt% in Pt–G content, however, the cell performance is rather decreased compared to that of 1.5 wt% Pt–G. It is ascribed to the blocking effect for proton conduction due to too much inorganic filler and possible loss of electrons through Pt network. The effect of SiO2 on cell performance seems to be different depending on Pt–G and relative humidity (RH). Open circuit voltage (OCV) is significantly affected by SiO2 content and increased with SiO2 content.

Korea conducts a national health screening program to improve and check-up on public health and in recent years, the screening usage has been increased. Given the increased screening usage for radiographic exams, this study predicts the frequency of using radiographic exams and the exposure dose. This study estimates the usage of radiographic exams by isolating radiographic exams from the 2011 analysis of the national health insurance corporation, and estimates the public exposure dose by applying each procedure`s dose table from UNSCEAR 2008. As a result of the analysis, in the 2011 National Health Screening, the average exposure dose per person is assumed to be 0.57 mSv, and depending on the type of screening program from the radiographic exam, an examinee could be exposed to between 0.2 mSv and 11.081 mSv. The frequency of using radiographic exposure was found to be 16,005,914 and the exposure dose was 6,311.76 person-Sv. The most frequent exam is the Chest X-ray, which was performed 1,070,567 (69.17%), and the UGI has the highest exposure dose at 5,217.94 person-Sv (82.67%). The outcome is categorized based on gender and age, excluding those under 39 years old. In all age groups, the screening usage and exposure dose are higher in females than in males. In particular, females between 50 and 54 years old have the highest screening usage (1,674,787, 10.5%) and exposure dose (701.59 person-Sv, 11.1%). As UGI accounts for 82.76% of procedures, except when done for medical purposes, if the government supports a voluntary UGI exam (which includes the UGI exam in the National Screening Program) or abolishes it completely, as seen overseas, the cost-effectiveness and validity of the UGI exam, as well as the exposure dose from the National Screening Program will all decrease significantly.

The objective of this study was to determine the effects of vitamin A (VA) as a supplementation to the diet of cows in late pregnancy on tissue development and birth traits in Korean native calves. In study 1, a VA supplementation at 24,000 IU per day was supplied to a high-VA group (n = 8) from 225 days in gestation to delivery. In study 2, pregnant cows treated with a high level of VA (n = 5) consumed a VA supplementation at 24,000 IU in period 1 (from 150 to 225 days in gestation). In period 2 (from 225 days in gestation to delivery), the treatment diet contained a VA supplementation of 78,000 IU per day. The level of serum VA of pregnant cows decreased as the day of delivery approached, both in the groups in study 1 and in study 2 (P P = 0.01). The level of serum VA of the offspring of pregnant cows fed the high levels of VA also increased by 28.6% (P = 0.033) compared to the control. In study 1 and 2, birth weight of calves in the high-VA group was heavier than the control. We found that the gene expression related muscle development (MyoD, Myf5, Myf6, MyoG, PPARγ, and LPL) tended to increase in the 31-day-old calf among pregnant cows treated with high levels of VA (P < 0.1). However, there were no significant differences either in the early or late adipogenic marker genes (ZFP423, ERK2, KLF2, FABP4, SCD) excluding C/EBPα. We suggest that supplementation of VA at 78,000 IU per day kept the level of serum VA from dropping in late-gestation cows and a sufficient level of VA could enhance both birth weight and muscle development marker genes in the pregnant cows’ offspring, contributing to increased productivity in the calf.

Pt nanoparticles were successfully deposited onto SiO2 nanoparticles sulfonated by different chemical sources such as H2SO4, CH3SO3H, Na2SO4, and HSO3Cl and denoted as Pt-HS/SiO2, Pt-CS/SiO2, Pt-NS/SiO2 and Pt-SS/SiO2, respectively. X-ray diffraction and X-ray photoelectron spectroscopy (XPS) analyses for Pt-containing sulfonated SiO2 nanoparticles were conducted to identify the phase, oxidation state of Pt incorporated and the existence of –SO3+ on SiO2 nanoparticles. Transmission electron microscope analysis shows 2–4 nm of Pt nanoparticles on the surface of SiO2 nanoparticle. The proton conductivities of various membranes are highly consistent with metallic Pt and –SO3+ contents based on XPS analysis. The membrane electrolyte assembly (MEA) fabricated with Nafion/Pt-NS/SiO2 composite membrane showing the smallest Pt particle size and excellent dispersion shows the best cell performance under zero humidity, following the order of Pt-NS/SiO2>Pt-HS/SiO2>Pt-CS/SiO2>Pt-SS/SiO2. It also shows that the MEA fabricated with Nafion/Pt-NS/SiO2 composite membrane shows the least decrease by 5.7% in open circuit voltage with relative humidity while that for Nafion/Pt-CS/SiO2 composite membrane is the largest by 15.3%. The results suggest that Pt particle size, its dispersion, metallic Pt and –SO3 contents are critical and quite different with chemical source for sulfonation, affecting the cell performance.

Hybrid-typed Pt electrocatalyst using Pt-carbon molecular sieve (Pt-CMS) synthesized by zeolite template method and commercial Pt-carbon black (Pt-CB) is prepared with different ratios of Pt-CB to Pt-CMS. Their physical and electrochemical properties are characterized using X-ray diffraction (XRD), transmission electron micrograph (TEM) and Brunauer–Emmet–Teller method (BET). Pt nanoparticles of 2–4 nm are synthesized and successfully dispersed onto CMS by polyol method and comparable with that of commercial Pt-CB. Cyclic voltammetric analysis is conducted to estimate electrochemical active surface area (ECSA). The cell test is conducted for the various membrane electrolyte assemblies (MEAs) fabricated with different catalysts such as Pt-CB, Pt-CMS, various hybrid-typed Pt-CB x /Pt-CMS100− x named as Pt-CB x /CMS100− x . The cell performance is fairly consistent with ECSA and the MEA fabricated with equal mass fraction of Pt-CB and Pt-CMS (Pt-CB50/CMS50) shows the best cell performance, indicating a significant dependence on pore structure of carbon support.

Background and objective CD8+ cell infiltration and apoptosis of airway epithelial cells are increased in chronic obstructive pulmonary disease (COPD). CD8+ T cells induce apoptosis by releasing granzymes, which can also cause extracellular matrix degradation and remodelling. Granzyme B levels and T cells expressing granzyme B are increased in bronchoalveolar lavage fluid of COPD patients, which suggests that granzyme B may contribute to the pathogenesis of COPD. This study provides quantitation of granzyme B-positive cells in relation to CD8+ cells in the small airway walls of emphysema. Methods Antibodies against CD8 and granzyme B were used to identify CD8+ and granzyme B+ cells. Volume fraction (Vv) of CD8+ and granzyme B+ cells were quantitated by the point counting method in the small airways of 13 non-smoker control subjects and 46 emphysema patients (14 panlobular emphysema (PLE) and 32 centrilobular emphysema (CLE) lungs). Immunohistochemical detection of macrophage scavenger receptor was also performed in randomly selected cases. Results The Vv of CD8+ and granzyme B+ cells in CLE was greater than those in control and PLE (both P

Graphene single nanosheet (GNS) is synthesized from graphite by chemical oxidation and thermal exfoliation at 1000 °C and confirmed by X-ray diffraction analysis. Scanning electron and transmission electron microscope images clearly show the lateral expansion of graphite sheet and uniform dispersion of Pt nanoparticles on GNS. Fourier transform infrared and X-ray photoelectron spectroscopy analyses are conducted for surface properties of GNS such as oxygenated functional groups. Cyclic voltammetric analysis shows that electrochemical active surface areas (ECSAs) for Pt/GNS, commercial Pt/Vulcan XC-72 carbon black and Pt-incorporated onto commercial carbon black (Pt/CB) prepared in the laboratory are 33.1 m 2 g −1 , 23.5 m 2 g −1 and 22.5 m 2 g −1 , respectively. Because of significant restacking of Pt/GNS sheets, carbon black (CB) with different content is intercalated between Pt/GNS as a spacer. The ECSAs of Pt/GNS, Pt/GNS/CB20, Pt/GNS/CB30 and Pt/GNS/CB40 are evaluated to be 31.5 m 2 g −1 , 28.6 m 2 g −1 , 38.8 m 2 g −1 and 30.4 m 2 g −1 , respectively. The cell performance highly depends on CB content and Pt/GNS/CB with 30 wt.% of CB content shows the best cell performance of 400 mA cm −2 .

Various Pt-containing silica nanoparticles were successfully synthesized and adopted in the fabrication of Nafion/silica and Nafion/Pt-containing silica composite membranes. X-ray diffraction and X-ray photoelectron spectroscopy analyses for Pt-containing silica nanoparticle were conducted to identify the phase and oxidation state of Pt incorporated onto silica nanoparticles. Transmission electron micrograph analysis shows 2–3 nm of Pt nanoparticles on the surface of silica nanoparticle. Water uptakes of Nafion/Pt-containing silicas and Nafion/silica composite membranes were measured. All these composite membranes show higher water uptakes than that of casting Nafion membrane. In addition, S-Pt/SiO 2 and Pt-S/SiO 2 composite membranes show a little higher water uptake than that of Nafion/Pt/SiO 2 composite membrane due to hydrophilic sulfonic group. The cell test using various MEAs shows that under zero humidity, Nafion/S-Pt/SiO 2 composite membrane shows 0.45 A/cm 2 at 0.6 V and even comparable to that of casting Nafion membrane under 100% humidity. It is seen that the cell performance was rather decreased with the increase of Pt-containing silica content due to water flooding and/or electron loss due to the electrical conduction transfer network formed by too much Pt within the membrane. Finally, in case of sulfonation, the order of sulfonation seems to be critical.

Along with increase in the frequency and exposure dose from the diagnostic medical radiation procedures, the public's interest in radiation exposure has also been growing. In this study, in order to estimate the Cumulative Exposure Frequency and the cumulative effective dose of diagnostic medical radiation in the Korean population, we included 680 diagnostic medical radiation procedure codes of the Health Insurance Review & Assessment Service's health insurance medical expenses data and adopted the effective dose data from the 2008 report of the United Nations Scientific Committee on the Effects of Atomic Radiation. We combined the data of one million individuals in the national sample cohort database (2002-10) of the National Health Insurance Service. The results revealed that 93.2% (917 972) of the subjects were exposed to diagnostic medical radiation at least once in the past nine years, and the Cumulative Exposure Frequency was 17 286.4 per 1000 individuals with a cumulative effective dose of 5.7 (±17.8) mSv per person. Additionally, 93.1% (854 480) of the subjects had a cumulative effective dose less than 20 mSv, and 0.7% (6139) had a dose that exceeded 100 mSv (extreme), showing that the dosage level was mostly low. However, the number of individuals whose exposure exceeded 100 mSv/y increased 28-fold, from 18 in 2002 to 500 in 2010. In addition, the size of increase also grew each year, suggesting that cancer occurrence due to diagnostic medical radiation may have also increased. In order determine the causal relationship between cancer occurrence and diagnostic medical radiation and setup a guideline for exposure, it is necessary to monitor individual cumulative exposure doses nation-wide and follow up on heavily exposed individuals for an extended period of time.

Well-ordered microporous carbon molecular sieve (CMS) with high surface area was successfully synthesized using zeolite Y as a template for the application in polymer electrolyte fuel cells (PEMFC). CMS is noncovalently functionalized with poly (diallyldimethylammonium chloride, PDDA) and loaded with Pt nanoparticles by reducing Pt precursor (H2PtCl6) in ethylene glycol via polyol method. X-ray photoelectron spectroscopy (XPS) analysis indicates that positively charged PDDA has been irreversibly adsorbed onto the hydrophobic surface of CMS via the π–π interaction between the unsaturated C C contaminants in PDDA chains. TEM images clearly show that the size of Pt nanoparticles deposited on CMS depends on the amount of PDDA and a significant amount of Pt particles has been anchored to the PDDA-functionalized CMS. The BET surface areas of Pt-PDDA-CMSs are inversely proportional to the amount of PDDA. The stability test for Pt-PDDA-CMS was conducted through repeated potential cycling experiment up to 1200 repeated cycles and exhibited much better stability compared to Pt-CMS and commercial Pt/C. It is seen that the higher the PDDA incorporation is, the larger the electrochemical active surface area is after 1200 repeated cycles of operation.

Purpose The combination of chemotherapy and radiotherapy is emerging as the new standard modality for the treatment of locally advanced head and neck cancer, due to the inherent functional and cosmetic sequelae associated with its surgical management. Combination chemotherapy with 5-fluorouracil and cisplatin (FP) is one of the most active regimens for the head and neck cancer. Furthermore, both agents are known to act as radiosensitizer. This study was conducted to determine the efficacy, feasibility, and the toxicities of concurrent FP chemotherapy with radiotherapy. Materials and methods Patients with histologically proven locally advanced head and neck cancer (T3-4 or node positive) were enrolled in the study. Patients received 5-fluorouracil, 1,000 mg/m2/day, continuously for 4 days, and cisplatin, 75 mg/m2, on day 1. This regimen was given every four weeks. The radiotherapy (45 Gy) was started on day 1 of the first cycle, and administered in 25 fractions. Following a three-week interval, the radiotherapy was resumed on day 1 of the third cycle of chemotherapy, and administered in 15 fractions (27 Gy). Results Of the 31 eligible patients included, 28 were able to be evaluated for the tumor response. The response rate for the 28 patients was 93% (16 complete responses, 10 partial responses). Disease free survival for the 16 complete responders was 37 months (median, 1 ~41 months), with a median follow-up time of 31 months. The 1-, 2-, and 3-year survival rates were 82%, 69%, and 63%, respectively. Regarding the feasibility of this treatments, only nineteen patients (61%) received the complete courses of scheduled treatments. The median duration of admission for all patients was 39 days. Grade 3 or 4 stomatitis were observed in 25 patients (83%) and appeared as the dose limiting toxicity of this regimen. Conclusion Although FP chemotherapy with concurrent radiotherapy is toxic, it is an effective and relatively feasible treatment for locally advanced head and neck cancer. The majority of patients experienced severe stomatitis, which appeared as the dose limiting toxicity of this regimen.

Divalent cation-exchanged ETS-4 such as Ca 2+ , Sr 2+ , and Ba 2+ was successfully prepared via ion exchange process. TPD analysis for CO 2 shows two distinct peaks based on 187 °C. As the pretreatment temperature increased from 200 °C to 250 °C in TPD analysis, the amount of desorbed CO 2 from high peak ( i.e. oxygen basic site) was decreased while that from low peak ( i.e. M 2+ -CO 2 interaction) was a little increased. Unexpectedly, the amount of CO 2 adsorbed on cation site for Ca-ETS-4 was the lowest despite that the electronegativity of Ca 2+ is the largest. It is attributed to possible shielding of small cation by the first few molecules of a cavity. The decrease of % change in the amount of CO 2 adsorbed on oxygen basic site with the increase in pretreatment temperature for Ca-ETS-4 was most significant arisen from weak basicity of oxygen basic site due to small electronegativity of Ca 2+ compared to other two cations. In case of large cation, Ba-ETS-4, however, the increase of % change in the amount of CO 2 adsorbed on cation site was most significant due to less shielding effect as well as higher degree of dehydration of Ba 2+ . The adsorption of CO 2 using BET apparatus was well consistent with that of a single adsorption capacity using gravimetric method.

Aims: The nuclear receptor liver X receptor-α (LXRα) stimulates lipogenesis, leading to steatosis. Nuclear factor erythroid-2-related factor-2 (Nrf2) contributes to cellular defense mechanism by upregulating antioxidant genes, and may protect the liver from injury inflicted by fat accumulation. However, whether Nrf2 affects LXRα activity is unknown. This study investigated the inhibitory role of Nrf2 in hepatic LXRα activity and the molecular basis. Results: A deficiency of Nrf2 enhanced the ability of LXRα agonist to promote hepatic steatosis, as mediated by lipogenic gene induction. In hepatocytes, Nrf2 overexpression repressed gene transactivation by LXR-binding site activation. Consistently, treatment of mice with sulforaphane (an Nrf2 activator) suppressed T0901317-induced lipogenesis, as confirmed by the experiments using hepatocytes. Nrf2 activation promoted deacetylation of farnesoid X receptor (FXR) by competing for p300, leading to FXR-dependent induction of small heterodimer partner (SHP), which was responsible for the repression of LXRα-dependent gene transcription. In human steatotic samples, the transcript levels of LXRα and SREBP-1 inversely correlated with those of Nrf2, FXR, and SHP. Innovation: Our findings offer the mechanism to explain how decrease in Nrf2 activity in hepatic steatosis could contribute to the progression of NAFLD, providing the use of Nrf2 as a molecular biomarker to diagnose NAFLD. As certain antioxidants have the abilities to activate Nrf2, clinicians might utilize the activators of Nrf2 as a new therapeutic approach to prevent and/or treat NAFLD. Conclusion: Nrf2 activation inhibits LXRα activity and LXRα-dependent liver steatosis by competing with FXR for p300, causing FXR activation and FXR-mediated SHP induction. Our findings provide important information on a strategy to prevent and/or treat steatosis. Antioxid. Redox Signal. 15, 2135–2146.