Ammonia-treated carbon-supported cobalt tungsten as fuel cell cathode catalyst

The ammonia-treated carbon-supported cobalt tungsten (Co-W/C) was prepared by a reaction employing a temperature program in a stream of NH₃ between 773 and 1073 K. The effects of the NH₃ heat-treatment temperature, Co-W ratio and the preparation method were investigated. The activity of Co-W/C for the oxygen reduction reaction (ORR) was evaluated using a rotating disc electrode and single fuel cell measurements. The Co-W/C prepared by the impregnation method with the same atomic ratio of Co and W, and NH₃ heat treated at 823 K, exhibited the highest ORR activity with an onset potential of 0.74 V (vs. RHE at 5 μA cm⁻²). The XRD and temperature-programmed measurements revealed that the catalyst active species were ascribed to the presence of CoW oxynitride and Co nitride. The catalyst surface was characterized as nitrided metal (accommodation of the N-atom in the host Co-W lattice resulting from a sufficient distance between the Co-W atoms and N) and N-containing carbon (Co surrounded by N-atoms and attached to the C support) by X-ray photoelectron spectroscopy. The Co-W oxynitrides, Co nitride and pyrrolic-type nitrogen of the N-containing carbons are likely responsible for the good ORR activity.     

Influence of initial curing conditions and exposure environments on chloride migration in concrete using electrochemical method

To investigate the influence of initial curing conditions and exposure environments on chloride ions’ migration in concrete, the specimens that were cured in different conditions and placed in several marine environments were studied. The amount of chloride ions passing through the specimen’s section was monitored in the accelerated chloride migration test. The effective chloride diffusion coefficients (D _e) were calculated from the steady-state on the basis of Nernst-Planck’s equation. The results indicated that the initial curing conditions and the wet-dry interval of external environments have coupling influence on effective diffusion coefficient of chloride ion significantly. D _e reflected the density and pore connectivity of concrete. The co-effects of the initial curing condition and following exposure environment should be taken into account in durability design for concrete structure located in marine environment.     

Effect of triacylglycerol species on the crystallizing behavior of a model water/oil emulsion

The crystallizing behavior of a model water/oil (W/O) emulsion with different fat formulas was investigated. The model W/O emulsion was stored in a programmable oven under a temperature fluctuation cycle of 5 °C for 12 h and 20 °C for another 12 h. Crystal growth was observed using a polarization microscope, until the crystals were over 100 μm in diameter, which causes texture degradation. We examined whether the texture degradation is related to the fatty acid formula and the triglyceride formula by carbon number. We also examined the effect of the triglyceride species concentration estimated from the fatty acid formula on the texture degradation. The palmitic acid content was related with texture degradation at high concentration among the fatty acid species. The triglyceride content was not related with texture degradation. Triacylglycerol species with palmitic acid such as tripalmitate (PPP) and 1,3‐dipalmitoyl‐2‐oleoyl‐glycerol (POP) were related with texture degradation. The summed up concentration of three triglycerides [PPP, POP and 1,2‐dipalmitoyl‐3‐oleoyl‐glycerol (PPO)] was related with texture degradation.     

A silanized mica substrate suitable for high-resolution fiber FISH analysis by scanning near-field optical/atomic force microscopy

We applied a novel silanized mica substrate with an extremely flat surface constructed according to Sasou et al. (Langmuir 19, 9845-9849 (2003)) to high-resolution detection of a specific gene on a DNA fiber by scanning near-field optical/atomic force microscopy (SNOM/AFM). The interaction between the substrate and fluorescence-dye conjugated peptide nucleic acid (PNA) probes, which causes fluorescence noise signal, was minimal. By using the substrate, we successfully obtained a fluorescence in situ hybridization signal from the ea47 gene on a λphage DNA labeled with an Alexa 532-conjugated 15-base PNA probe. As the results, no fluorescence noises were observed, indicating that the surface adsorbed almost none of the PNA probe. The combination of the substrate and SNOM/AFM is an effective tool for visualizing DNA sequences at nanometer-scale resolution.     

Synbiotic promotion of epithelial proliferation by orally ingested encapsulated Bifidobacterium breve and raffinose in the small intestine of rats

We evaluated the effects of Bifidobacterium breve JCM1192(T )and/or raffinose on epithelial proliferation in the rat small and large intestines. WKAH/Hkm Slc rats (4 wk old) were fed a control diet, a diet supplemented with either encapsulated B. breve (30 g/kg diet, 1.5 x 10(7) colony-forming unit/g capsule) or raffinose (30 g/kg diet), or a diet supplemented with both encapsulated B. breve and raffinose, for 3 wk. Epithelial proliferation in the small intestine, as assessed by bromodeoxyuridine immunohistochemistry, was increased only in the B. breve plus raffinose-fed group. We determined the number of bifidobacteria in cecal contents using fluorescence in situ hybridization and confirmed the presence of ingested B. breve only in the B. breve plus raffinose-fed group. This suggests that the ingested B. breve cells used raffinose and were activated in the small intestine, where they subsequently influenced epithelial proliferation. In conclusion, we found a prominent synbiotic effect of encapsulated B. breve in combination with raffinose on epithelial proliferation in rat small intestine but not in large intestine. To our knowledge, this is the first report of a synbiotic that affects epithelial proliferation.     

Impact of Wisteria floribunda Agglutinin-Positive Mac-2-Binding Protein in Patients with Hepatitis C Virus-Related Compensated Liver Cirrhosis

We aimed to examine the effect of Wisteria floribunda agglutinin-positive Mac-2-binding protein (WFA⁺-M2BP) level on survival comparing with other laboratory liver fibrosis markers in hepatitis C virus (HCV)-related compensated liver cirrhosis (LC) (n = 165). For assessing prognostic performance of continuous fibrosis markers, we adapted time-dependent receiver operating characteristics (ROC) curves for clinical outcome. In time-dependent ROC analysis, annual area under the ROCs (AUROCs) were plotted. We also calculated the total sum of AUROCs in all time-points (TAAT score) in each fibrosis marker. WFA⁺-M2BP value ranged from 0.66 cutoff index (COI) to 19.95 COI (median value, 5.29 COI). Using ROC analysis for survival, the optimal cutoff point for WFA⁺-M2BP was 6.15 COI (AUROC = 0.79348, sensitivity = 80.0%, specificity = 74.78%). The cumulative five-year survival rate in patients with WFA⁺-M2BP ≥ 6.15 COI (n = 69) was 43.99%, while that in patients with WFA⁺-M2BP < 6.15 COI (n = 96) was 88.40% (p < 0.0001). In the multivariate analysis, absence of hepatocellular carcinoma (p = 0.0008), WFA⁺-M2BP < 6.15 COI (p = 0.0132), achievement of sustained virological response (p < 0.0001) and des-γ-carboxy prothrombin < 41 mAU/mL (p = 0.0018) were significant favorable predictors linked to survival. In time-dependent ROC analysis in all cases, WFA⁺-M2BP had the highest TAAT score among liver fibrosis markers. In conclusion, WFA⁺-M2BP can be a useful predictor in HCV-related compensated LC.     

Tn Antigen Expression Defines an Immune Cold Subset of Mismatch-Repair Deficient Colorectal Cancer

Colorectal cancer (CRC) cells often express Tn antigen, a tumor-associated truncated immature O-glycan (GalNAcα-O-Ser/Thr) that can promote tumor progression. Immunotherapies against Tn antigen have been developed and are being evaluated in clinical trials. Tn antigen can also be considered a novel immune checkpoint that induces immunosuppressive signaling through glycan-biding lectins to lead effector T cell apoptosis. We evaluated the correlation of Tn antigen expression by immunohistochemistry with mismatch-repair (MMR) status, tumor-infiltrating lymphocytes, tumor cell PD-L1 expression, and clinicopathological characteristics in 507 CRC patients. Although 91.9% of CRCs showed negative or weak Tn antigen staining (Tn-negative/weak), we identified a small subset of CRCs (8.1%) that displayed particularly intense and diffuse distribution of Tn antigen immunoreactivity (Tn-strong) that closely related to deficient MMR (dMMR). Moreover, 40 dMMR CRCs were stratified into 24 Tn-negative/weak dMMR tumors (60.0%) exhibiting dense CD8+ lymphocyte infiltrate concomitant with a high rate of PD-L1 positivity, and 16 Tn-strong dMMR tumors (40.0%) that demonstrated CD8+ T cell exclusion and a lack of PD-L1 expression, which was comparable to those of proficient MMR. Our finding suggests that the immune cold subset of patients with Tn-strong dMMR CRC may be effectively treated with immune checkpoint blockade therapy or cellular immunotherapy targeting Tn antigen.     

The influence of Goishi tea on adipocytokines in obese mice

This study investigated the influence of Goishi-tea on visceral fat weight in induced obese mice. Mice were divided into two main groups, normal and obesity. In obesity group, mice were fed with high-fat diet. Goishi-tea including its fractions (ethyl-acetate layer and water layer) was administrated in normal and obesity three sub-groups. Results showed no influence of Goishi-tea in normal group. However, visceral fat weight, size of adipose cell and cholesterol level were significantly decreased in obesity group fed Goishi-tea compared to control group. Moreover, adiponectin levels tended to increase and adipocytokines has significant values lower in obesity group fed Goishi-tea compared to control group. Interestingly, Goishi tea involved in the high-fat diet induced-obese mice can inhibit fat accumulation and maintain adiponectins without increasing tumor necrosis factor-alpha and interleukin-6. It would be beneficial for the prevention of metabolic syndrome and obesity-related disorder.