This paper reviews our computational studies on several building blocks for highly functional π-electron silicon nanomaterials by the introduction of an anionic system. We insisted that the design of building blocks possessed strictly genuine π electrons: π-conjugation on planar/linear skeletons. Though silicon is in the same group of the periodic table as carbon, the geometric structure of the unsaturated silicon compounds is nonclassical: trans-bent at silicon-silicon double and triple bonds, and chair-like at a six-membered silicon ring. We have theoretically designed a linear silicon-silicon triple bond and a D_6h-symmetric six-membered silicon ring with extra electrons instead of conventional substituents such as alkyl, aryl, etc. We summarize here our main findings and discuss the key points to realize the classical structure etc. in the π-electron silicon system.

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It is essential to understand the physical mechanisms determining the plasma rotation velocity profile for achieving steady state operations in a fusion reactor. Physical mechanisms related to plasma rotation velocity profiles have been investigated through transient transport analysis in the JT-60U tokamak device. Main results are as follows: (i) Fast ion losses due to the magnetic field ripple induce the plasma rotation as a momentum source in the peripheral region of plasma; (ii) The momentum diffusivity and the convection velocity are evaluated from the transient transport analysis using the momentum source induced by the fast ion losses; (iii) Correlations between the momentum diffusivity, the convection velocity, and the ion thermal diffusivity have been found; (iv) Parameter dependences of the momentum transport coefficients (the momentum diffusivity and the convection velocity) have been identified; (v) The measured plasma rotation profiles are almost reproduced through the momentum diffusivity and the convection velocity with a small ion pressure gradient; (vi) Intrinsic rotation, which is not determined by the momentum transport coefficients and the external momentum input has been observed with a large ion pressure gradient. Also another type of the intrinsic rotation, which is driven by electron cyclotron resonance heating, has been identified.

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In the last few decades, numerous antibodies have increasingly contributed to identifying protein-protein interactions which significantly advanced experimental research such as understanding cell signaling pathways. In addition, a number of antibodies have been developed for antibody therapeutics targeting specific molecules. It has been difficult, however, to produce anti-carbohydrate antibodies with high affinities since carbohydrates are self-antigens. To overcome this problem, we took advantage of phage-display technologies which make in vitro production of anti-carbohydrate antibodies possible. We have successfully obtained anti-carbohydrate antibodies with reasonably high affinities for reducing mannose residues or tumor-associated antigens. Phage-display technologies are excellent in obtaining genes of such antibodies. However, for further improving the affinities or designing and constructing chimeric molecules for example, production, purification and characterization of the antibody proteins are the most critical steps in order to select the best-available antibodies which can be developed to be antibody therapeutics or diagonostics. In this review, we summarize not only the outcome of our in vitro production of anti-carbohydrate antibodies by the phage-display technology but also the major problems involved in expression of anti-carbohydrate antibodies in cells.

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Living organisms, such as, plants, animals and microorganisms produce various biopolymers while consuming minimal amounts of energy. This study investigates the formation mechanisms of structural biopolymers and applies mechanisms, such as controlling the molecular orientation or allowing the polymer to self-organize, in order to synthetically reproduce biopolymers whose properties mimic those found naturally. Establishing energy efficient polymer system technologies for biopolymers, such as proteins, will allow the reduction of energy consumption in many polymer processing applications. Silk is one example of a biopolymer produced with minimum energy requirements. Silk is a fine, lustrous, filament produced by the silkworm, Bombyx mori, after it has consumed large amounts of naturally grown mulberry leaves. It has appealing fiber characteristics including its pearl-like gloss, velvety touch and is comfortable to wear in all seasons. The silkworm accurately controls the molecular orientation by combining numerous sophisticated spinning technologies such as liquid crystal, high speed spinning, dry spinning, super drawing, ion control, complex spinning, porous and crimp spinning. We also show that silkworms and a silk-producing spider incorporate atmospheric CO₂ into their silk fibers. We found that C¹³-labelled CO₂ under controlled atmospheric conditions is incorporated into silk fibers in the carbonyl groups of alanine, aspartic acid, serine and glycine and the C_γ of aspartic acid. These results demonstrate that silkworm has incorporated atmospheric CO₂ into silk fiber via the TCA cycle. Finally, it is important that we reconstruct the energy-efficient polymer system technology of these biopolymers with aims to reduce energy consumption in many other polymer processing applications.

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Several studies have shown that β cell possesses a limited potential for regeneration upon cellular toxicity and tissue injury. One of the difficulties in studying β-cell regeneration has been the lack of an animal model system that allow β-cell loss and subsequent proliferation. Here we examined the regenerative and/or proliferative capacity of β cells by severely destroying β cells and by restoring hyperglycemia in streptozotocin (STZ)-induced diabetic model. Animals were made diabetic by a single intraperitoneally injection of high dose of STZ, and blood glucose level was kept in normal range with twice-daily insulin detemir (long-acting human insulin analog) or islet transplantation for 10 weeks. In insulin detemir-treated mice, hyperglycemia was reversed and glycemic control was successful, but no β-cell increase or new formation was detected. In contrast, in islet transplanted mice, β cells and islets increased, and islet structure was greatly recovered. This recover involved both increased neogenesis and replication. Our results suggest that the effect of insulin detemir on the pancreatic β cell was very different from islet transplantation, and that islet transplantation could be a trigger for the induction of new formation and replication.

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The direct annual costs in medical care of type 2 diabetes mellitus outpatients were analyzed. The total annual medical cost and the cost per visit of patients with type 2 diabetes were as follows: without complications, \130,473 ± 104,147 (Mean ± SD) and \13,046 ± 7,568; with one complication, \151,431 ± 130,529 and \16,206 ± 10,777; with two complications, \240,088 ± 148,022 and \18,357 ± 10,409; with three complications, \263,150 ± 141,754 and \23,739 ± 11,068; with four complications, \355,343 ± 177,080 and \30,822 ± 16,148. We also analyzed the costs of artificial dialysis, the quality of life (QOL) in patients. The direct cost per month in medical care of outpatients with dialysis and diabetes were \428,609 ± 40,876. The samples of patients were given questionnaires to assess QOL, and the score of KDQOL-SF (the Kidney Disease Quality of Life instrument-Short Form) in patients with dialysis were as follows: without diabetes, 63.94 ± 15.96, and with diabetes, 47.32 ± 17.39. The QOL scores of SF-36 in patients with diabetes became lower as the number of complications increased as follows: without complications, 73.09 ± 9.57; with one complication, 67.71 ± 8.33; with two complications, 60.17 ± 8.61; with three complications, 37.94 ± 9.24; with four complications, 36.42 ± 14.52. Because all QOL scores by KDQOL-SF were lower and medical costs per month are much more expensive in patients with dialysis and diabetes than patients with only dialysis, reducing QOL scores and medical costs are important and hence there should be provisions for secondary and tertiary prevention of complications along with the primary prevention of disease.

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Recently, the presence and function of D-amino acids in mammals, including humans, have been reported. In particular, a relationship between an increase in the D-amino acid content of specific proteins and aging and senescence-related diseases has been proposed. However, this hypothesis remains unproven. Here, we focused on Alzheimer′s disease, a well known senescence-related disease, and used high performance liquid chromatography (HPLC) to analyze the degree of change in the D-amino acid content in the Alzheimer′s disease−elated proteins PP1C, GLRX1 and NF-L. Cerebrums of SAM (senescence-accelerated mice), an animal model of Alzheimer′s disease, were used. Increases in D-serine and D-aspartic acid contents with aging in PP1C were found. PP1C is a catalytic subunit of PP1 (serine/threonine phosphatase 1). Tau, one of the most important molecules involved in Alzheimer′s disease, is a target of PP1C. Hyperphosphorylation of Tau is thought to be a trigger of Alzheimer′s disease. Moreover, the involvement of PP1C in cognitive function and memory, independently of dephosphorylation of Tau, has been suggested. The results of this study suggest that substitution of L-amino acids with D-amino acids alters the physical properties of PP1C, and this, in turn, causes its malfunction, which may lead to the onset of Alzheimer′s disease.

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The present study was conducted to identify the risk factors which could lead to hospitalization or institutionalization among the frail elderly receiving in-home care in Japan. The follow up study was conducted in 7 nursing home stations in Sapporo, Japan. Informed consent was received from 86 pairs of caregivers and disabled elderly in October 2008. We excluded 15 patients aged 64 years or younger and their caregivers. Thus, in total we analyzed 71 pairs. Among the 71 pairs, 2 died at home. Dying at home is regarded as successful in-home care and therefore those 2 cases were included for the analysis in the present study. The follow-up period of the present study was defined as 6 months. We confirmed the current home health care situation by mail for family caregivers. Frail female elderly were revealed to be at a significant low risk of institutionalization or hospitalization (HR=0.17, 95%CI=(0.04, 0.80)). The present cohort study is now being produced, and we intend to continue to report on it in the future.

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