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Shinkan Tokudome,1 Ryosuke Ando,2 Yoshiro Koda,3 1Department of Nutritional Epidemiology, National Institute of Health and Nutrition, Shinjuku-ku, Tokyo, 2Department of Nephro-urology, Nagoya City University Graduate School of Medical Sciences, Mizuho-ku, Nagoya, 3Department of Forensic Medicine and Human Genetics, Kurume University School of Medicine, Kurume, Japan Abstract: The discoveries and application of prostate-specific antigen (PSA) have been much appreciated because PSA-based screening has saved millions of lives of prostate cancer (PCa) patients. Historically speaking, Flocks et al first identified antigenic properties in prostate tissue in 1960. Then, Barnes et al detected immunologic characteristics in prostatic fluid in 1963. Hara et al characterized γ-semino-protein in semen in 1966, and it has been proven to be identical to PSA. Subsequently, Ablin et al independently reported the presence of precipitation antigens in the prostate in 1970. Wang et al purified the PSA in 1979, and Kuriyama et al first applied an enzyme-linked immunosorbent assay for PSA in 1980. However, the positive predictive value with a cutoff figure of 4.0 ng/mL appeared substantially low (~30%). There are overdiagnoses and overtreatments for latent/low-risk PCa. Controversies exist in the PCa mortality-reducing effects of PSA screening between the European Randomized Study of Screening for Prostate Cancer (ERSPC) and the US Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. For optimizing PCa screening, PSA-related items may require the following: 1) adjustment of the cutoff values according to age, as well as setting limits to age and screening intervals; 2) improving test performance using doubling time, density, and ratio of free: total PSA; and 3) fostering active surveillance for low-risk PCa with monitoring by PSA value. Other items needing consideration may include the following: 1) examinations of cell proliferation and cell cycle markers in biopsy specimens; 2) independent quantification of Gleason grading; 3) developing ethnicity-specific staging nomograms based on tumor stage, PSA value, and Gleason score; 4) delineation of the natural history; 5) revisiting the significance of the androgen/testosterone hypothesis; and 6) devoting special attention to individuals with a certain genetic predisposition. Finally, considering the uncertainty that exists in medicine, risk communication on PSA-based screening is indeed due. Keywords: application, benefits and harm, discovery, optimization, PCa screening, PSA

In this study, the basic properties of Ba2AgSi3 were investigated in detail from both experimental and computational viewpoints. Polycrystalline Ba2AgSi3 formed by an arc-melting apparatus under an argon atmosphere was ground into powders, and then powder samples were sintered using the spark plasma sintering method. Both n-type and p-type samples were obtained. This may be due to a slight deviation from the stoichiometric composition. The energy bandgap of Ba2AgSi3 was measured to be around 0.17 eV from the temperature dependence of electrical conductivity and was in agreement with that by first-principles calculations. Sintered samples exhibited a high Seebeck coefficient of −273 μV K−1 and a high power factor of 0.38 mW m−1 K−2 at 307 K for n-type samples. They were 217 μV K−1 and 0.23 mW m−1 K−2, respectively, at 320 K for p-type samples. The electronic structures of impurity-doped Ba2AgSi3 were also discussed using first-principles calculations to investigate the insertion site of impurity atoms. The calculations suggest that the substitution of B (P) at any Si site shifts the Fermi level and transforms it into p-type (n-type) semiconductors. On the other hand, substitution of Ba or Ag sites with B or P is unlikely to occur in terms of formation energy. [ABSTRACT FROM AUTHOR]

We give a homotopy classification of the global defects in ordered media and explain it via the example of biaxial nematic liquid crystals, that is, systems where the order parameter space is the quotient of the three-sphere S3 by the quaternion group Q. As our mathematical model, we consider continuous maps from complements of spatial graphs to the space S3/Q modulo a certain equivalence relation and find that the equivalence classes are enumerated by the six subgroups of Q. Through monodromy around meridional loops, the edges of our spatial graphs are marked by conjugacy classes of Q ; once we pass to planar diagrams, these labels can be refined to elements of Q associated with each arc. The same classification scheme applies not only in the case of Q but also to arbitrary groups. [ABSTRACT FROM AUTHOR]

We introduce the concept of a handlebody decomposition of a three-manifold, a generalization of a Heegaard splitting, or a trisection. We show that two handlebody decompositions of a closed orientable three-manifold are stably equivalent. As an application to materials science, we consider a mathematical model of polycontinuous patterns and discuss a topological study of microphase separation of a block copolymer melt. [ABSTRACT FROM AUTHOR]

Teye K, Quaye I K E, Koda Y, Soejima M, Tsuneoka M, Pang H, Ekem I, Amoah A G B, Adjei A, Kimura H. A−61C and C−101G Hp gene promoter polymorphisms are, respectively, associated with ahaptoglobinaemia and hypohaptoglobinaemia in Ghana. We have investigated the genetic basis for the Hp0 phenotype amongst 123 randomly selected Ghanaians. A total of 17 individuals were determined to be Hp0 phenotype, based on the classical method for Hp phenotyping of Hb-supplemented plasma. Out of the 17 Hp0 individuals, nine subjects were further classified as ahaptoglobinaemic and eight as hypohaptoglobinaemic by Western blots and double immunodiffusion. We identified three previously known base substitutions (A−55G, A−61C and T−104A) and three new ones (C−101G, T−191G and C−242T) within the 5′ flanking region of the Hp gene. The A−61C base substitution significantly decreased transcriptional activity and was associated strongly with Hp 2 allele and ahaptoglobinaemia. The C−101G substitution was similar in transcriptional activity to the wild-type and was associated with Hp 1S allele and hypohaptoglobinaemia. The Hp del allele seen in Asian populations was absent. We conclude that the Hp0 phenotype in Ghana has a genetic basis that differs significantly from that seen in Asia. [ABSTRACT FROM AUTHOR]

The aim of this study is to identify a specific degradation of concrete that has been observed in bridge decks made of reinforced concrete (RC). To control the phenomenon, fundamental studies were conducted. Compressive loads and external water pressure were cyclically applied to submerged concrete cylinder specimens with different pre-loading and restraint conditions. The turbidity of the water in the tank was generally observed during the loading, and the pH of the turbid water steadily increased as the number of cycles increased. Thereafter, fine aggregates without a cement matrix were found on the inner surfaces of split specimens. These phenomena were quantitatively analyzed, and the analyses suggested that cyclic water pressure acted on the inside of pre-cracked specimens and washed out their cement matrix. The degradation of a rough cracked surface was also examined using the cyclic shear test, with/without a water supply to the crack. The shear slip and the orthogonal displacement were clearly amplified with an increase in the number of cycles when the water supply was present. The mechanical properties of cracked concrete with water in shear was discussed in accordance with that of liquefaction. These fundamental studies could help to determine the acceleration factors of the degradation and provide certain thresholds for practical use.

It is known that the fatigue resistance of concrete decreases when the concrete is saturated with water and that the compressive strength increases with increasing water content at low temperatures below the freezing point of water. However, there have been few systematic studies on the influence of the ambient temperature and moisture content on the fatigue resistance of concrete. In the present study, static loading and fatigue tests were carried out on concrete cylinders to determine their fatigue resistance under compression. The test methods had been conducted to considered environmental temperatures and water contents. The results indicated that at room temperature, the static compressive strength decreases with increasing moisture content. In contrast, at a low temperature, the compressive strength of the samples increased with increasing moisture content. Furthermore, regardless of the temperature, the fatigue resistance decreased as the moisture content increased.