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951.
Microbial synthesis of copolymers of [R]-3-hydroxybutyrate (3HB) and 4-hydroxybutyrate (4HB), P(3HB-co-4HB), by Alcaligenes eutrophus, Alcaligenes latus, and Comamonas acidovorans from various carbon sources has been studied. The copolyester compositions varied from 0 to 100 mol% 4HB, depending on the microorganism and the combination of carbon substrates supplied. The thermal and physical properties of compositions with 0–100 mol% 4HB were investigated. The copolyesters represented a wide variety of polymeric materials, from hard crystalline plastic to very elastic rubbers, depending on composition. The copolyester films with high 4HB fractions (64–100 mol% 4HB) exhibited the characteristics of a thermoplastic elastomer, and the tensile strength increased from 17 to 104 MPa as the 4HB fraction increased. The enzymatic degradation of P(3HB-co-4HB) films was studied in an aqueous solution of extracellular polyhydroxybutyrate (PHB) depolymerase from Alcaligenes faecalis or lipase from Rhizopus delemer. The erosion rate of P(3HB-co-4HB) films was strongly dependent on the copolymer composition. In addition, environmental degradation of P(3HB-co-4HB) films in sea water was investigated. 相似文献
952.
Kazuki Kai Masafumi Moriyama A. S. M. Rafiul Haque Taichi Hattori Akira Chinju Chen Hu Keigo Kubota Yuka Miyahara Noriko Kakizoe-Ishiguro Shintaro Kawano Seiji Nakamura 《International journal of molecular sciences》2021,22(17)
Tumor-associated macrophages (TAMs) promote cancer cell proliferation and metastasis, as well as anti-tumor immune suppression. Recent studies have shown that tumors enhance the recruitment and differentiation of TAMs, but the detailed mechanisms have not been clarified. We thus examined the influence of cancer cells on the differentiation of monocytes to TAM subsets, including CD163+, CD204+, and CD206+ cells, in oral squamous cell carcinoma (OSCC) using immunohistochemistry, flow cytometry, and a cytokine array. Furthermore, we investigated the effect of OSCC cells (HSC-2, SQUU-A, and SQUU-B cells) on the differentiation of purified CD14+ cells to TAM subsets. The localization patterns of CD163+, CD204+, and CD206+ in OSCC sections were quite different. The expression of CD206 on CD14+ cells was significantly increased after the co-culture with OSCC cell lines, while the expressions of CD163 and CD204 on CD14+ cells showed no change. High concentrations of plasminogen activator inhibitor-1 (PAI-1) and interleukin-8 (IL-8) were detected in the conditioned medium of OSCC cell lines. PAI-1 and IL-8 stimulated CD14+ cells to express CD206. Moreover, there were positive correlations among the numbers of CD206+, PAI-1+, and IL-8+ cells in OSCC sections. These results suggest that PAI-1 and IL-8 produced by OSCC contribute to the differentiation of monocytes to CD206+ TAMs. 相似文献
953.
Y. Sagehashi A. Ito† T. Ohtake M. Nakamura K. Yagi† K. Ogawa† T. Katsuyama† M. Yoshida† K. Oshiro‡ W. Aoki‡ 《International journal of cosmetic science》2009,31(2):153-154
IFSCC Magazine , 11 (2008) (1) 11–18
In collaboration with medical institutions, we have been providing makeup guidance to people with facial skin color problems under the name >>therapy makeup«. The aim of therapy makeup is to reduce the anxiety and tension associated with the appearance of people with skin color problems and to provide psychological support, thereby helping them live more normal lives. Ota's nevus (blue birthmarks) and port-wine stain (red birthmarks) the leading causes of abnormal skin coloration. We have already developed covering foundations for Ota's nevus and port-wine stain using a light-filtering technology. Another common cause of abnormal skin coloration is vitiligo (white patches). Vitiligo cannot be adequately covered by conventional cosmetic foundations. Therefore, we developed a new covering foundation for vitiligo based on optical characteristics. Moreover, the effects of makeup on the psychology of patients with vitiligo were objectively evaluated using psychometrically established quality of life indices. It was demonstrated that makeup helped to alleviate the psychological anxiety and tension of patients, resulting in improvement of social relationships and self-esteem.
The integration of medical care and beauty care enables therapy makeup to improve quality of life of patients with skin color disorders. 相似文献
In collaboration with medical institutions, we have been providing makeup guidance to people with facial skin color problems under the name >>therapy makeup«. The aim of therapy makeup is to reduce the anxiety and tension associated with the appearance of people with skin color problems and to provide psychological support, thereby helping them live more normal lives. Ota's nevus (blue birthmarks) and port-wine stain (red birthmarks) the leading causes of abnormal skin coloration. We have already developed covering foundations for Ota's nevus and port-wine stain using a light-filtering technology. Another common cause of abnormal skin coloration is vitiligo (white patches). Vitiligo cannot be adequately covered by conventional cosmetic foundations. Therefore, we developed a new covering foundation for vitiligo based on optical characteristics. Moreover, the effects of makeup on the psychology of patients with vitiligo were objectively evaluated using psychometrically established quality of life indices. It was demonstrated that makeup helped to alleviate the psychological anxiety and tension of patients, resulting in improvement of social relationships and self-esteem.
The integration of medical care and beauty care enables therapy makeup to improve quality of life of patients with skin color disorders. 相似文献
954.
Mutsuyo Ohara Shuichi Nakamura Norio Shibata 《Advanced Synthesis \u0026amp; Catalysis》2011,353(18):3285-3289
A direct three‐component reaction of aldehydes, amines and diaryl phosphites was catalyzed by a zinc(II) complex of 1,3‐bis(imidazolin‐2‐ly)pyridine (pybim) giving the corresponding α‐aminophosphonates in good yield with good enantioselectivity. The reaction was applied to a wide variety of aromatic aldehydes to give products with excellent yields (up to 99%) and enantiomeric excesses (up to 93% ee). 相似文献
955.
Noriyuki Hara Shuichi Nakamura Yasuhiro Funahashi Norio Shibata 《Advanced Synthesis \u0026amp; Catalysis》2011,353(16):2976-2980
The organocatalytic enantioselective decarboxylative addition of malonic acids half thioesters to isatins using a squaramide catalyst afforded the products with high enantioselectivity. These products are key intermediates in the synthesis of 3‐substituted 3‐hydroxy‐2‐oxindole derivatives. The first enantioselective synthesis of (−)‐flustraminol B has been accomplished. 相似文献
956.
Jyomoto T Azuma M Islam NN Fujinami R Takao T Ogawa T Tabuchi M Igarashi K Kato J Ooshima H 《Journal of Bioscience and Bioengineering》2006,102(3):193-197
The enzyme that catalyzes N-acyl linkage between myristic acid and the NH(2)-terminal glycine residue of the octapeptide Gly-Asn-Ala-Ala-Ala-Ala-Arg-Arg-NH(2) in aqueous solution without ATP and coenzyme A was found in Pseudomonas aeruginosa. The enzyme was purified from cell-free crude extract using DEAE-Cellulose, Sephadex G-200, CM-Sephadex C-50, and hydroxyapatite column chromatographies, and then purified approximately 1900-fold with about 1.5% recovery of enzyme activity from the crude extract. Finally, the purified enzyme showed a main band on SDS polyacrylamide gel electrophoresis after staining with Coomassie Brilliant Blue. The band corresponded to a molecular mass of approximately 60 kDa. The K(m)s of the purified enzyme for the substrate myristic acid and the octapeptide were 0.36 and 2.6 mM, respectively. When myristoyl-CoA instead of myristic acid was used as the substrate for the enzyme reaction, myristoyl octapeptide could be synthesized as observed in the case of myristic acid. The K(m) of myristoyl-CoA was 0.17 mM. 相似文献
957.
We present experimental results verifying the optical robustness of a 1 x 1 multimode interference (MMI) device that is directly butt coupled with optical fibers at 70 degrees C for 1050 h and discuss the gradual increase of polarization dependent loss. Based on this structure, an electro-optic (EO) MMI waveguide device that can control the output optical power by using an electrode structure located directly on top of the multimode is presented. As a proof of principle, we demonstrate the switching operation of the EO-MMI device using commercially available chromophore as the active EO material. 相似文献
958.
Mitamura K Imae T Mouri E Torikai N Matsuoka H Nakamura T 《Journal of nanoscience and nanotechnology》2006,6(1):36-42
Hybrid Langmuir and Langmuir-Blodgett monolayers of a perfluorooctadecanoic acid mixed with a rigid block copolymer, poly(3,5-bis(3,5-bis(benzyloxy)benzyloxy)benzyl methacrylate-randommethacrylic acid)-block-poly(2-perfluorooctylethyl acrylate), which is composed of benzyloxy dendron side chains and perfluorinated side chains, were prepared and characterized by surface pressure-surface area isotherms, atomic force microscopic images and neutron and X-ray reflectometries. The two-dimensionally phase-separated structures of monolayer films and their morphologies with plateau and terrace were confirmed. The monolayers were separated into a dendron layer, a perfluorinated layer, and a carboxyl layer. The layer formation is originated not only in the intermolecular interaction between a perfluorooctadecanoic acid and a block copolymer but also in the geometry of the molecules. Especially, the amphiphilicity of perfluorinated surfactant plays a role to the ordered array of the block copolymers. 相似文献
959.
Yamada A Koizumi H Nishimura S Sonoyama N Kanno R Yonemura M Nakamura T Kobayashi Y 《Nature materials》2006,5(5):357-360
The rechargeable lithium-ion cell is an advanced energy-storage system. However, high cost, safety hazards, and chemical instability prohibit its use in large-scale applications. An alternative cathode material, LiFePO(4), solves these problems, but has a kinetic problem involving strong electron/hole localization. One reason for this is believed to be the limited carrier density in the fixed monovalent Fe(3+)PO(4)/LiFe(2+)PO(4) two-phase electrode reaction in LixFePO4. Here, we provide experimental evidence that LixFePO4, at room temperature, can be described as a mixture of the Fe(3+)/Fe(2+) mixed-valent intermediate LialphaFePO4 and Li1-betaFePO4 phases. Using powder neutron diffraction, the site occupancy numbers for lithium in each phase were refined to be alpha=0.05 and 1-beta=0.89. The corresponding solid solution ranges outside the miscibility gap (0相似文献
960.
Katsuhiro Narasaki Shoji Tsunematsu Kiyomi Ootsuka Kenichi Kanao Akinobu Okabayashi Kazuhisa Mitsuda Hiroshi Murakami Takao Nakagawa Kenichi Kikuchi Ryota Sato Hiroyuki Sugita Youichi Sato Masahide Murakami Masanori Kobayashi 《低温学》2012,52(4-6):188-195
This report describes the results and operating status of ground lifetime testing and achievements on orbit of coolers for space use. Ground lifetime tests of coolers of three types were conducted to demonstrate their long life and reliability. Three single-stage Stirling coolers were tested for 89,016, 71,871 and 68,273 h from 1998, a two-stage Stirling cooler was tested for 72,906 h, and a 4-K class cooler with a two-stage Stirling cooler and a Joule–Thomson cooler was tested for over 2.5 years. After lifetime tests were completed, a few coolers were investigated to determine the cause of the cooling performance degradation. Additionally, the filled gas of the coolers was analyzed. These coolers have shown good results on orbit. Three single-stage Stirling coolers were carried on the X-ray astronomical satellite “SUZAKU” (launched in July 2005), Japanese lunar polar orbiter “KAGUYA” (launched in September 2007), and the Japanese Venus Climate Orbiter “AKATSUKI” (launched in June 2010). Two units of a two-stage Stirling cooler were carried on the infrared astronomical satellite “AKARI” launched in February 2006. A 4-K class cooler was carried on the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) aboard the Japanese Experiment Module (JEM) of the International Space Station (ISS). SMILES was launched in September 2009. 相似文献