Circulating Exosomal miR‐20b‐5p Inhibition Restores Wnt9b Signaling and Reverses Diabetes‐Associated Impaired Wound Healing

At present, developing therapeutic strategies to improve wound healing in individuals with diabetes remains challenging. Exosomes represent a promising nanomaterial from which microRNAs (miRNAs) can be isolated. These miRNAs have the potential to exert therapeutic effects, and thus, determining the potential therapeutic contributions of specific miRNAs circulating in exosomes is of great importance. In the present study, circulating exosomal miRNAs are identified in diabetic patients and assessed for their roles in the context of diabetic wound healing. A significant upregulation of miR‐20b‐5p is observed in exosomes isolated from patients with type 2 diabetes mellitus (T2DM), and this miRNA is able to suppress human umbilical vein endothelial cell angiogenesis via regulation of Wnt9b/β‐catenin signaling. It is found that the application of either miR‐20b‐5p or diabetic exosomes to wound sites is sufficient to slow wound healing and angiogenesis. In diabetic mice, it is found that knocking out miR‐20b‐5p significantly enhances wound healing and promotes wound angiogenesis. Together, these findings thus provide strong evidence that miR‐20b‐5p is highly enriched in exosomes from patients with T2DM and can be transferred to cells of the vascular endothelium, where it targets Wnt9b signaling to negatively regulate cell functionality and angiogenesis.     

Fabrication and characterization of micro-tubular cathode-supported SOFC for intermediate temperature operation

We report the fabrication and characterization of a micro-tubular cathode-supported cell consisting of a Ce_0.9Gd_0.1O_1.95 electrolyte with a Ni–cermet anode on a porous La_0.6Sr_0.4Co_0.2Fe_0.8O_3−δ/Ce_0.9Gd_0.1O_1.95 (60:40 volume) tube (460 μm wall thickness and 2.26 mm diameter). The cells were fabricated by a cost-effective technique involving extrusion molding and slurry coating through a co-firing process. Densification of the ceria film (thickness < 15 μm) was successful by co-firing the laminated electrolyte with the porous cathode at 1200 °C. NiO–Ce_0.9Gd_0.1O_1.95 (Ni: Ce_0.9Gd_0.1O_1.95 = 50:50 in volume after reduction) was subsequently sintered on the electrolyte at 1100 °C to construct a 10 μm thick, porous and well-adherent anode. The cell having 1.5 cm tube length fed with humidified 30 vol.% H₂–Ar (3% H₂O) yielded the maximum power densities of 0.16, 0.13 and 0.11 W cm⁻², at 600, 550 and 500 °C, respectively. It was found that the cell performance is strongly dominated by the tube length, due to a high substrate resistance from the cathode current collections.     

Purification and characterization of an l-amino acid oxidase from Pseudomonas sp. AIU 813

An l-amino acid oxidase was found from a newly isolated strain, Pseudomonas sp. AIU 813. This enzyme was remarkably induced by incubation with l-lysine as a nitrogen source, and efficiently purified using an affinity chromatography with l-lysine as ligand. The enzyme oxidized l-lysine, l-ornithine and l-arginine, but not other l-amino acids and d-amino acids. The oxidase activity for l-lysine was detected in a wide pH range, and its optimal was pH 7.0. In contrast, the oxidase activity for l-ornithine and l-arginine was not shown in acidic region from pH 6.5, and optimal pH for both substrates was 9.0. The enzyme was a flavoprotein and composed of two identical subunits with molecular mass of 54.5?kDa. The N-terminal amino acid sequence was similar to that of putative flavin-containing amine oxidase and putative tryptophan 2-monooxygenase, but not to that of l-amino acid oxidases.     

Anomalous Resonance Phenomena in Two-Dimensional Electrons on the Surface of 3He-4He Liquid Mixtures

No Heading We report on anomalous resonance phenomena observed in a two-dimensional electron system on ³He-⁴He liquid mixtures. The resonance is observed in a Corbino conductivity measurement, in which a magnetic field B is applied prependicular to the electron sheet. We have detected the resonances for ³He concentrations n₂ from 0.475% to 10.20%, and at temperatures below 800 mK. The resonance frequency f_r is inversely proportional to B. In a preliminary study we found that f_r and the resonance amplitude increases when the electron sheet is not parallel to the electrode, and this made the understanding difficult. Here we have made the systematic measurement keeping the parallelism between the electrons and the electrode. We have observed the resonance only at n₃ > 0.475%. This fact finally leads us to conclude that adding ³He atoms to liquid ⁴He induces the nonuniformity in local electron density, and hence the resonance.PACS numbers: 73.20.–r, 67.60.–g     

Alkane isomerization on MoO3/ZrO2 catalysts

Molybdenum was used as an alternative to sulfate as promoter of zirconia for alkane isomerization reactions. It has similar effects to sulfate, tungstate and phosphate ions, modifying the physicochemical properties of unpromoted zirconia. Mo‐promoted zirconia catalysts do not show any activity for n‐C₄ isomerization. For n‐C₇ isomerization, the catalytic activity depends on Mo content, crystalline structure of the support and the molybdenum oxospecies present on the surface of the catalysts. This revised version was published online in July 2006 with corrections to the Cover Date.     

Preparation and characterization of a nanofiber mat consisting of Tetra‐PEG prepolymers

Tetra‐PEG gel, which has been known as a mechanically tough and biocompatible gel, was processed into a nanofiber mat by electro‐spinning (ES) and 2‐step treatment process using w/o type emulsion consisted of the Tetra‐PEG prepolymer 1‐octanol/water solution. The 2‐step treatment was carried out in order to increase the cross‐linking points to the as‐spun nanofibers. From this study, we succeeded in insolubilizing poly(ethylene glycol) (PEG) nanofiber, and it was found that the Tetra‐PEG gel nanofiber mat showed high tensile property even at swollen state. The elastic modulus at equilibrium swollen state was 4.5 kPa. In addition, we compared the differences of the structure and tensile property between the Tetra‐PEG nanofiber mat and porous Tetra‐PEG gel prepared by freeze‐dry method. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41353.     

Photoinitiation properties of heterocyclic hexaarylbiimidazoles with high UV‐vis absorbance

Four heterocyclic hexaarylbiimidazoles, BFuTM‐HABI, BThTM‐HABI, BCTFu‐HABI, and BCTTh‐HABI, were synthesized to improve the UV‐vis absorption properties of hexaarylbiimidazoles. UV‐vis spectra, fluorescence spectra, ESR measurements, photo‐dilatometer experiments, and photo‐DSC measurements indicate that BCTFu‐HABI and BCTTh‐HABI exhibit better UV‐vis absorption abilities and photoinitiation activities for acrylate derivatives with different functionalities than BFuTM‐HABI and BThTM‐HABI, respectively. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Production of Carbon Nanotubes and Other Nanostructures Via Continuous 3-Phase AC Plasma Processing

The highly flexible plasma system allows the independent flow control of plasma gas, carbonaceous feedstock and metal catalyst. Further important control parameters include current intensity and product quenching rate yielding in an excellent control of the thermal history of the carbon products. Temperature profiles measured along the reactive flow of carbon particles are presented, mapping time-temperature relations for typical operating conditions. In addition, the principle product families are presented. From the characteristics observed and NT product analysis, it is concluded that the AC plasma technology shows a significant potential for the continuous production of bulk quantities of carbon-based nanotubes of controlled properties and novel tube-like nanostructures.     

Hot topic: Pregnancy-induced expression of interferon-stimulated genes in the cervical and vaginal mucosal membranes

In ruminants, IFN-tau (IFNT) is a pregnancy recognition signal secreted by the embryonic trophectoderm before implantation, and it induces the expression of IFN-stimulated genes (ISG) in the uterine endometrium and blood leukocytes. The expression of ISG in blood leukocytes could indicate the presence of a viable conceptus before return of the next estrus; however, expression levels have high variation for confirming pregnancy. We hypothesized that the secreted IFNT in the uterus would affect ISG expression in cervical and vaginal tissues because they are directly adjacent to the uterus. To prove the hypothesis, we investigated the expression of 3 ISG (ISG15, MX1, and MX2) in cervical and vaginal mucosal membranes collected from pregnant (n = 12) and nonpregnant (n = 11) lactating Holstein cows at 17 to 18 d after artificial insemination. Mucosal membrane samples of the cervical canal near the external os (cervix) and deep vaginal wall surrounding the external os (vagina) were collected separately by simply scraping with a curette on d 17 or 18 of pregnancy (d 1 = ovulation), at which time IFNT secretion into the maternal uterus is maximal. After pregnancy diagnosis on d 30 and 60, separately collected samples confirmed as pregnant and nonpregnant were used for evaluation of the expression of IFN-stimulated protein 15 kDa (ISG15) and myxovirus-resistance protein 1 and 2 (MX1, MX2) with quantitative real-time PCR. The collected mucosal membrane samples from cervix contained mostly cell clots showing membrane structure and a low content of blood cells. The expression levels of all 3 genes were significantly increased in pregnant cows compared with nonpregnant cows in both cervical and vaginal samples. These results suggest that increased expression of ISG in the cervix and vagina is a pregnancy-associated phenomenon and is highly affected by IFNT secreted from the conceptus through the uterus.