Relationship between Expression of Onco-Related miRNAs and the Endoscopic Appearance of Colorectal Tumors

Accumulating data indicates that certain microRNAs (miRNAs or miRs) are differently expressed in samples of tumors and paired non-tumorous samples taken from the same patients with colorectal tumors. We examined the expression of onco-related miRNAs in 131 sporadic exophytic adenomas or early cancers and in 52 sporadic flat elevated adenomas or early cancers to clarify the relationship between the expression of the miRNAs and the endoscopic morphological appearance of the colorectal tumors. The expression levels of miR-143, -145, and -34a were significantly reduced in most of the exophytic tumors compared with those in the flat elevated ones. In type 2 cancers, the miRNA expression profile was very similar to that of the exophytic tumors. The expression levels of miR-7 and -21 were significantly up-regulated in some flat elevated adenomas compared with those in exophytic adenomas. In contrast, in most of the miR-143 and -145 down-regulated cases of the adenoma-carcinoma sequence and in some of the de novo types of carcinoma, the up-regulation of oncogenic miR-7 and/or -21 contributed to the triggering mechanism leading to the carcinogenetic process. These findings indicated that the expression of onco-related miRNA was associated with the morphological appearance of colorectal tumors.     

Hydrostatic Pressure Influences HIF-2 Alpha Expression in Chondrocytes

Hypoxia-inducible factor (HIF)-2α is considered to play a major role in the progression of osteoarthritis. Recently, it was reported that pressure amplitude influences HIF-2α expression in murine endothelial cells. We examined whether hydrostatic pressure is involved in expression of HIF-2α in articular chondrocytes. Chondrocytes were cultured and stimulated by inflammation or hydrostatic pressure of 0, 5, 10, or 50 MPa. After stimulation, heat shock protein (HSP) 70, HIF-2α, nuclear factor kappa B (NF-κB), matrix metalloproteinase (MMP)-13, MMP-3, and vascular endothelial growth factor (VEGF) gene expression were evaluated. The levels of all gene expression were increased by inflammatory stress. When chondrocytes were exposed to a hydrostatic pressure of 5 MPa, HIF-2α, MMP-13, and MMP-3 gene expression increased significantly although those of HSP70 and NF-κB were not significantly different from the control group. In contrast, HIF-2α gene expression did not increase under a hydrostatic pressure of 50 MPa although HSP70 and NF-κB expression increased significantly compared to control. We considered that hydrostatic pressure of 5 MPa could regulate HIF-2α independent of NF-κB, because the level of HIF-2α gene expression increased significantly without upregulation of NF-κB expression at 5 MPa. Hydrostatic pressure may influence cartilage degeneration, inducing MMP-13 and MMP-3 expression through HIF-2α.     

Ethanol Conversion on MCM-41 and FSM-16, and on Ni-Doped MCM-41 and FSM-16 Prepared without Hydrothermal Conditions

MCM-41 and FSM-16 were both prepared using no hydrothermal conditions, and nickel was doped into these catalysts (Ni-MCM-41 and Ni-FSM-16) using a template ion exchange method. FSM-16 and Ni-FSM-16 had greater catalytic activity for the conversion of ethanol than MCM-41 and Ni-MCM-41, indicating that FSM-16 has potential as a catalyst for the conversion of ethanol to propylene.     

Enhancement of the Passive Direct Methanol Fuel Cells Performance by Modification of the Cathode Microporous Layer Using Carbon Nanofibers

Mass transfer is a key parameter affecting the performance of the passive direct methanol fuel cells (DMFCs), which work under natural convection. In this study, effect of carbon nanofibers (CNFs) addition to the cathode microporous layer (MPL) on the performance of the passive DMFCs was investigated. The results indicated that CNFs content has a significant influence on both of the mass transport and the electrochemical surface area (ECSA). Interestingly, addition of the CNFs (20 wt.%) leads to increase the power density of the passive DMFC to 160% compared to pristine carbon black MPL. At low current density, the CNFs content has no influence on the performance, while at high current density the maximum performance can be obtained at 20 wt.% CNFs then the performance decreases with further increase in the CNFs content. Although the highest catalyst utilization is observed at 40 wt.% CNFs, a maximum power density of 36 mW cm^–2 can be obtained at 20 wt.% CNFs and this is related to the significant effect of the mass transfer resistance under the passive operation conditions. Overall, addition of CNFs to the MPL can be considered an effective strategy to modify the passive DMFCs performance.     

Isolation and characterization of poly(butylene succinate-co-butylene adipate)-degrading microorganism

Poly(butylene succinate-co-butylene adipate) (PBSA)-degrading bacterium, strain 1-A, was isolated from soil. Strain 1-A was identified as Bacillus pumilus on the basis of its physiological properties and partial 16S rRNA gene sequence. Strain 1-A also degraded poly(butylene succinate) (PBS) and poly(epsilon-caprolactone). On the other hand, poly(butylene adipate terephthalate) and poly(lactic acid) were minimally degraded by strain 1-A. The NMR spectra of degradation products from PBSA indicated that the adipate units were more rapidly degraded than 1,4-butanediol and succinate units. This seems to be one of the reasons why strain 1-A degraded PBSA faster than PBS.     

The effect of the N-linked glycans on structural features and physicochemical functions of soybean β-conglycinin homotrimers

β-Conglycinin is a trimeric protein consisting of three subunits, α,α′,and β, which are N-glycosylated. The α and α′ subunits contain extension regions in addition to core regions common to all subunits. We purified homogeneous trimers consisting of only α, α′, or β from mutant soybean cultivars containing β-conglycinin lacking one or two subunits: α homotrimers from an α′-lacking mutant, α′ homotrimers from an α-lacking mutant, and β homotrimers from an α-and α′-lacking mutant. Structural features and physicochemical functions of the three homotrimers were examined and compared with those of recombinant homotrimers having no N-linked glycans. The native homotrimers have secondary structures very similar to those of the recombinant ones. In analogy with the recombinant homotrimers, the native ones exhibit different thermal stabilities from one another (β>α′>α), and the native α and α′ homotrimers exhibit better solubility, emulsifying ability, and heat-induced association than the native β homotrimer. Further, the N-linked glycans contribute to solubilities of the three subunits at low ionic strength (μ=0.08) and to the emulsifying ability of the native β homotrimer. N-Linked glycans also prevent heat-induced associations of the native α and α′ homotrimers but do not contribute to the secondary structure and the thermal stability of β-conglycinin.     

The Impact of Duodenal Mucosal Vulnerability in the Development of Epigastric Pain Syndrome in Functional Dyspepsia

An unidentified cause of functional dyspepsia (FD) is closely associated with medication resistance. Acid suppression is a traditional and preferential method for the treatment of FD, but the efficacy of this treatment varies between epigastric pain syndrome (EPS) and postprandial syndrome (PDS): it is efficient in the former but not much in the latter. Transepithelial electrical resistance (TEER), a surrogate of mucosal barrier function, was measured under pH 3 and pH 5 acidic conditions using duodenal biopsy specimens obtained from the patients with EPS and PDS and asymptomatic healthy controls. The infiltration of inflammatory cells to the duodenal mucosa was accessed by immunohistochemical analysis. The duodenal mucosal TEER in EPS patients was decreased by exposure to the acidic solution compared to that of the controls and the PDS patients. The decrease in TEER of the EPS patients was observed even under pH 5 weak acidic condition and was correlated to degree of the epigastric pain. Moreover, the duodenal mucosa of EPS patients presented an increase in mast cells and plasma cells that expressed Ig-E. Duodenal mucosal vulnerability to acid is likely to develop EPS.     

Freeze-dried solid foams prepared from carbon nanotube aqueous suspension: Application to gas diffusion layers of a proton exchange membrane fuel cell

Freeze-dried macroporous solid foams were prepared from the multi-walled carbon nanotube (MWCNT) aqueous suspensions dispersed by chitosan. Thin film shaped CNT solid foams were prepared, and applied to the gas diffusion layers (GDLs) of a laboratory scale proton exchange membrane fuel cell (PEMFC). It was demonstrated that the prepared carbon foams in this study were useful to a fuel cell GDL material. The prepared cell performances were fairly comparable to the cell prepared with conventional carbon paper for GDL material. The microstructures of the prepared carbon foams were found to affect on the PEMFC performances. It was suggested that the interconnected carbon networks formed during the freezing step closely link to the cell performances. Hence, the defection of the interconnected microstructure lead degradation of the GDL quality. The impedance measurement made clear that the prepared foam materials were also advantageous for reducing the ohmic resistance in PEMFC assembly. The kinetic resistance values and the thermal conductive characteristics suggested that the freezing process would also control the degree of overlaps among single CNTs in a freeze-dried bulk that influenced on the electrochemical properties.     

Determination of Ring-OSF Position in Czochralski Silicon Single Crystals by Numerical Analysis of Distribution of Grown-in Defects

A numerical analysis technique that incorporates Voronkov's model were examined and used to estimate the distribution of defects during crystal growth. By comparisons of the distribution of the density of LSTD and the position of R-OSF in non-nitrogen-doped (non-N-doped) and nitrogen-doped (N-doped) silicon crystals, it is found that the results of the numerical analyses agree with practically evaluated data. The observations suggest that the R-OSF nucleus is a VO2 complex that is formed by bonds between oxygen atoms and residual vacancies consumed during the formation of void defects. This suggests that Voronkov's model can be used to accurately predict the generation and growth of defects in silicon crystals. This numerical analysis technique was also found to be an effective method of estimating the distribution of defects in silicon crystals during crystal growth.     

Cooling of3He-4He dilute solution down to 97 μK. Thermal boundary resistance between dilute solution and metal powder

We have cooled a³He-⁴He dilute solution down to 97 K, which is the lowest temperature ever been achieved in a dilute mixture. However, there is no sign of the superfluid transition of³He quasiparticles in the solution. In the sub-millikelvin region, we have measured the thermal boundary resistance between the solutions and sintered metal powder as a function of temperature T. We find that the thermal boundary resistence is proportional to T^–2 below 1 mK and that the resistance shows a strong dependence on magnetic fields below 0.1 T. These results suggest that the magnetic coupling is dominant in this temperature region. We have also estimated the heat leak into the dilute solution. It is found that the heat leak is proportional to the power of one third of inverse time, and the main source of the heat leak is ascribed to the viscous movement of³He quasiparticles.