The Complete Loss of p53 Expression Uniquely Predicts Worse Prognosis in Colorectal Cancer

p53 immunohistochemistry is considered an accurate surrogate marker reflecting the underlying TP53 mutation status and has utility in tumor diagnostics. In the present study, 269 primary CRCs were immunohistochemically evaluated for p53 expression to assess its utility in diagnostic pathology and prognostication. p53 expression was wild-type in 59 cases (23%), overexpressed in 143 cases (55%), completely lost in 50 cases (19%), and cytoplasmic in 10 cases (4%). p53 immunoreactivity was associated with tumor size (p = 0.0056), mucus production (p = 0.0015), and mismatch repair (MMR) system status (p < 0.0001). Furthermore, among CRCs with wild-type p53 expression, a significantly higher number of cases had decreased CDX2 than those with p53 overexpression (p = 0.012) or complete p53 loss (p = 0.043). In contrast, among CRCs with p53 overexpression, there were significantly fewer ALCAM-positive cases than p53 wild-type cases (p = 0.0045). However, no significant association was detected between p53 immunoreactivity and the “stem-like” immunophenotype defined by CDX2 downregulation and ALCAM-positivity. Multivariate Cox hazards regression analysis identified tubular-forming histology (hazard ratio [HR] = 0.17, p < 0.0001), younger age (HR = 0.52, p = 0.021), and female sex (HR = 0.55, p = 0.046) as potential favorable factors. The analysis also revealed complete p53 loss (HR = 2.16, p = 0.0087), incomplete resection (HR = 2.65, p = 0.0068), and peritoneal metastasis (HR = 5.32, p < 0.0001) as potential independent risk factors for patients with CRC. The sub-cohort survival analyses classified according to chemotherapy after surgery revealed that CRC patients with wild-type p53 expression tended to have better survival than those with overexpression or complete loss after chemotherapy. Thus, immunohistochemistry for p53 could be used for the prognostication and chemotherapy target selection of patients with CRC.     

Study on effects of solar radiation and rain on shrinkage, shrinkage cracking and creep of concrete

In this paper, the effects of actual environmental actions on shrinkage, creep and shrinkage cracking of concrete are studied comprehensively. Prismatic specimens of plain concrete were exposed to three sets of artificial outdoor conditions with or without solar radiation and rain to examine the shrinkage. For the purpose of studying shrinkage cracking behavior, prismatic concrete specimens with reinforcing steel were also subjected to the above conditions at the same time. The shrinkage behavior is described focusing on the effects of solar radiation and rain based on the moisture loss. The significant environment actions to induce shrinkage cracks are investigated from viewpoints of the amount of the shrinkage and the tensile strength. Finally, specific compressive creep behavior according to solar radiation and rainfall is discussed. It is found that rain can greatly inhibit the progresses of concrete shrinkage and creep while solar radiation is likely to promote shrinkage cracking and creep.     

Synthesis of stable and soluble one-handed helical poly(substituted acetylene)s without chiral pendant groups via polymer reaction in membrane state

A soluble and stable one-handed helical conjugated polymer without the coexistence of any other chiral moieties was successfully synthesized by asymmetric-induced polymerization of a chiral monomer having two hydroxyl groups followed by desubstitution of the chiral groups in a solid membrane state. The reason for the success was the polymer reaction was carried out in the membrane state. This is an alternative method to obtain such a unique chiral polymer which was obtained only by the helix-sense-selective polymerization (HSSP) we reported before. In addition the efficiency of the chiral induction was higher than that of the HSSP. It is interesting that the “Membrane state” acted like as if a protecting group.     

陶瓷色料中添加发色离子的状态与反应

固体滴定法是研究固溶量的一种新方法。本实验选择Mn-Al2O3色料,给其中加入Cr2O3,通过测定反射光谱f(R)、晶格常数、电子自旋共振（ESR）,并计算晶格常数,分别得到加入Cr2O3前后的Mn-Al2O3的反射光谱与晶格常数的变化,依据该数据来推定着色离子Mn的固溶量及化学状态。为研究Mn-Al2O3红色料中Mn的固溶量,给其中加入Cr2O3,它使Mn-Al2O3红的色调发生变化,在此过程中发生如下反应：Cr^3 Mn^3 →Cr^4 Mn^2 ,Mn-Al2O3红色料在反射光谱520nm处有吸收峰值,给其中添加Cr2O3后峰值减小,用Cr^3 的固溶量（即Cr2O3的添加量）和峰值Δf(R)作图并延伸图线至Δf(R)=0点,此点对应的Cr2O3值即为Mn^3 的固溶量（Mn2O3的浓度）。实验证明,利用固体滴定法在一定精度范围内测定发色元素的固溶量取得一定程度成功。锰红色料中的发色离子状态为Mn^3 ,添加Cr2O3后,Cr能置换Mn-Al2O3中的Mn。铬是以Cr^3 化学状态固溶到Al2O3中的。     

Dielectric response and polarization mechanism of alkali silicate glasses in gigahertz to terahertz frequency range

Oxide glasses are dielectric materials with potential applications in high-frequency communications; hence, their dielectric properties in the gigahertz to terahertz frequency range should be investigated. In this study, the dielectric properties of silica glass and five single alkali silicate glasses were measured at 0.5–10 THz using terahertz time-domain spectroscopy and far-infrared spectroscopic ellipsometry. At 0.5–10 THz, the silica glass exhibited low dielectric dispersion with a low dielectric constant and loss. By contrast, the alkali silicate glasses exhibited high dielectric dispersion, and the dielectric constant and loss were higher than those of the silica glass. The shape of the dielectric dispersion profile depended on the alkali-metal ions; it was broader for lighter ions such as Li ions and sharper for heavier ions such as Cs ions. The peak dielectric loss shifted toward a lower frequency as the weight of the alkali-metal ions in the alkali-silicate glass increased. To understand the dielectric dispersion, the complex permittivity was calculated using molecular dynamics simulations. The theoretical results qualitatively agreed with the experimental data. Ion dynamics analysis revealed that alkali-metal ions vibrate and migrate under an applied electric field, which affects the dielectric constant and loss of alkali-silicate glasses at gigahertz to terahertz frequencies. To fabricate filter devices at low temperatures, alkali metals should be added to silicate glass; therefore, a minimum amount of light alkali metals should be used to minimize the dielectric loss of the glass materials while maintaining productivity.     

Indentation-induced ductile behavior of glass–ceramics involving layered aluminosilicates

Contact damage in materials is critical in engineering applications because it influences mechanical resistance, such as wear, erosion, and impact failure. Indentation tests were performed using a tungsten carbide ball indenter (Hertzian contact) on the surfaces of glass–ceramics containing hexagonal CaAl₂Si₂O₈ or mica crystals (fluorophlogopite), both of which have a layered structure. The stress–strain relation and the permanent deformation on the surface, as well as the observation of the microcrack zone by X-ray computed tomography using synchrotron radiation, revealed that the glass–ceramic with hexagonal CaAl₂Si₂O₈ showed ductility similar to the quasi-plastic behavior previously observed in the mica glass–ceramic. The yield stresses of the glass–ceramics were estimated from the stress deviating from the stress–strain relation assuming complete elastic response between the ball and the sample. The ratio of the yield stress to Young modulus (Y/E) of the glass–ceramic with hexagonal CaAl₂Si₂O₈ was determined to be higher than that of the mica glass–ceramic.     

Band Gap Modification of Diamond Photonic Crystals by Changing the Volume Fraction of the Dielectric Lattice

Photonic crystals with a diamond structure of epoxy lattices in which TiO₂-based ceramic particles are dispersed were fabricated by stereolithography. The periodicity of the lattice was designed to reflect electromagnetic waves in the gigahertz range. The volume fraction (β) of the dielectric lattice medium was modified from 14% to 33% by changing the rod diameter of the lattice. The photonic band gap was observed along Γ-L 〈111〉, Γ-X 〈100〉, and Γ-K 〈110〉 directions and the complete photonic band gap was formed at over β= 20%. The width of the forbidden gap increased gradually when the β increased over 14%, and reached 2.4 GHz at β= 33%. These results agreed with the band calculation using the plane wave expansion method.     

Pore structure of carbons coated on ceramic particles

Pore structure of carbon coated on ceramic particles by carbonization of precursor in a powder mixture at 900 °C was studied by focusing on the effects of substrate ceramics (MgO, TiO₂ and various phases of Al₂O₃) and of carbon precursor (poly(vinyl alcohol) (PVA), poly(ethylene terephthalate) (PET) and hydroxyl propyl cellulose (HPC)). By dissolving substrate MgO particles, carbon coated was found to have a high BET surface area, more than 1000 m²/g, which was almost the same as the value estimated from apparent surface area measured on carbon-coated MgO particles under the assumption of zero surface area of the substrate. The carbon separated was found to be rich in micropores from the analyses by DFT method and α_s plot. The dependence of the BET surface area on the amount of carbon coated on TiO₂ with a high surface area was the same for three carbon precursors, although the carbon yields from the precursors were slightly different. Porous Al₂O₃ substrates, γ-Al₂O₃as-received and that formed from Al(OH)₃ during carbonization, gave a high BET surface area, but dense Al₂O₃, α-Al₂O₃, gave a low surface area.     

Structure and properties of poly(vinyl alcohol)/κ‐carrageenan blends

Blends of a commercial atactic poly(vinyl alcohol) (a‐PVA) derived from vinyl acetate and κ‐carrageenan were prepared by mixing the aqueous solutions of both samples. Blend films prepared by casting were transparent. In the DSC curves of the blend films, the endothermic peaks shifted to lower temperature with an increase of the content of κ‐carrageenan. The Young's modulus and the strength at break increased with an increase of the content of a‐PVA. As the standing temperature of the blend solutions decreased, the gelation region increased also at high content of carrageenan. In the amorphous regions of blend films, a‐PVA and κ‐carrageenan were miscible. © 2001 Society of Chemical Industry