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11.
Shinichiro Nakamura Kenichi Nakajima Yasushi Kondo Tetsuya Nagasaka 《Journal of Industrial Ecology》2007,11(4):50-63
Abstract: A general analytical model of materials flow analysis (MFA) incorporating physical waste input-output is proposed that is fully consistent with the mass balance principle. Exploiting the triangular nature of the matrix of input coefficients, which is obtained by rearranging the ordering of sectors according to degrees of fabrication, the material composition matrix is derived, which gives the material composition of products. A formal mathematical definition of materials (or the objects, the flow of which is to be accounted for by MFA) is also introduced, which excludes the occurrence of double accounting in economy-wide MFAs involving diverse inputs. By using the model, monetary input-output (IO) tables can easily be converted into a physical material flow account (or physical input-output tables [PIOT]) of an arbitrary number of materials, and the material composition of a product can be decomposed into its input origin. The first point represents substantial saving in the otherwise prohibitive cost that is associated with independent compilation of PIOT. The proposed methodology is applied to Japanese IO data for the flow of 11 base metals and their scrap (available as e-supplement on the JIE Web site). 相似文献
12.
Mori T Hidaka M Lin YC Yoshizawa I Okabe T Egashira S Kojima H Nagano T Koketsu M Takamiya M Uchida T 《Biochemical and biophysical research communications》2011,406(3):5355-443
Pin1, a peptidyl prolyl cis/trans isomerase (PPIase), is a potential target molecule for cancer, infectious disease, and Alzheimer’s disease. We established a high-throughput screening method for Pin1 inhibitors, which employs a real-time fluorescence detector. This screening method identified 66 compounds that inhibit Pin1 out of 9756 compounds from structurally diverse chemical libraries. Further evaluations of surface plasmon resonance methods and a cell proliferation assay were performed. We discovered a cell-active inhibitor, TME-001 (2-(3-chloro-4-fluoro-phenyl)-isothiazol-3-one). Surprisingly, kinetic analyses revealed that TME-001 is the first compound that exhibits dual inhibition of Pin1 (IC50 = 6.1 μM) and cyclophilin, another type of PPIase, (IC50 = 13.7 μM). This compound does not inhibit FKBP. This finding suggests the existence of similarities of structure and reaction mechanism between Pin1 and cyclophilin, and may lead to a more complete understanding of the active sites of PPIases. 相似文献
13.
Sumitomo Shinichiro Tatemoto Yukihiro Fukui Shin Nakamura Taka-aki Fukushima Shoji Ito Nobuyuki Mori Masahiko 《Virchows Archiv. B, Cell pathology including molecular pathology》1985,49(1):395-399
Virchows Archiv B Cell Pathology - Paget cells from cases of mammary and extramammary Paget’s disease were examined for carcinoembryonic antigen (CEA) and CEA-related antigens by the... 相似文献
14.
Differential gene expression profiling between wild-type and ALAS2-null erythroblasts: identification of novel heme-regulated genes 总被引:1,自引:0,他引:1
Fujiwara T Harigae H Takahashi S Furuyama K Nakajima O Sun J Igarashi K Yamamoto M Sassa S Kaku M Sasaki T 《Biochemical and biophysical research communications》2006,340(1):105-110
To identify erythroid-specific heme-regulated genes, we performed differential expression analysis between wild-type and heme-deficient erythroblasts, which had been prepared from wild-type and erythroid-specific delta-aminolevulinate synthase-null mouse ES cells, respectively. Among 8737 clones on cDNA array, 40 cDNA clones, including 34 unknown ESTs, were first selected by their high expression profiles in wild-type erythroblasts, and evaluated further for their erythroid-lineage specificity, expression in hematopoietic tissues in vivo, and heme-dependent expression, which yielded 11, 4, and 4 genes, respectively. Because of the selection strategy employed, the final 4 were considered as the newly identified erythroid-specific heme-regulated genes. These 4 genes were uncoupling protein 2, nucleolar spindle-associated protein, cellular nucleic acid-binding protein, and a novel acetyltransferase-like protein. These findings thus suggest that heme may regulate a wide variety of hitherto unrecognized genes, and further analysis of these genes may clarify their role in erythroid cell differentiation. 相似文献
15.
Rice plant development: from zygote to spikelet 总被引:27,自引:0,他引:27
Itoh J Nonomura K Ikeda K Yamaki S Inukai Y Yamagishi H Kitano H Nagato Y 《Plant & cell physiology》2005,46(1):23-47
Rice is becoming a model plant in monocotyledons and a model cereal crop. For better understanding of the rice plant, it is essential to elucidate the developmental programs of the life cycle. To date, several attempts have been made in rice to categorize the developmental processes of some organs into substages. These studies are based exclusively on the morphological and anatomical viewpoints. Recent advancement in genetics and molecular biology has given us new aspects of developmental processes. In this review, we first describe the phasic development of the rice plant, and then describe in detail the developmental courses of major organs, leaf, root and spikelet, and specific organs/tissues. Also, for the facility of future studies, we propose a staging system for each organ. 相似文献
16.
Yamazaki D Tabara Y Kita S Hanada H Komazaki S Naitou D Mishima A Nishi M Yamamura H Yamamoto S Kakizawa S Miyachi H Yamamoto S Miyata T Kawano Y Kamide K Ogihara T Hata A Umemura S Soma M Takahashi N Imaizumi Y Miki T Iwamoto T Takeshima H 《Cell metabolism》2011,14(2):231-241
TRIC channel subtypes, namely TRIC-A and TRIC-B, are intracellular monovalent cation channels postulated to mediate counter-ion movements facilitating physiological Ca(2+) release from internal stores. Tric-a-knockout mice developed hypertension during the daytime due to enhanced myogenic tone in resistance arteries. There are two Ca(2+) release mechanisms in vascular smooth muscle cells (VSMCs); incidental opening of ryanodine receptors (RyRs) generates local Ca(2+) sparks to induce hyperpolarization, while agonist-induced activation of inositol trisphosphate receptors (IP(3)Rs) evokes global Ca(2+) transients causing contraction. Tric-a gene ablation inhibited RyR-mediated hyperpolarization signaling to stimulate voltage-dependent Ca(2+) influx, and adversely enhanced IP(3)R-mediated Ca(2+) transients by overloading Ca(2+) stores in VSMCs. Moreover, association analysis identified single-nucleotide polymorphisms (SNPs) around the human TRIC-A gene that increase hypertension risk and restrict the efficiency of antihypertensive drugs. Therefore, TRIC-A channels contribute to maintaining blood pressure, while TRIC-A SNPs could provide biomarkers for constitutional diagnosis and personalized medical treatment of essential hypertension. 相似文献
17.
Abundance, isotopic composition and morphological imprints of the planktonic foraminifera Globorotalia scitula (Brady) were closely examined for possible use as a novel reconstruction tool of chemical environments in sub-intermediate depth seawater in the past. Based on the MOCNES plankton tow observation of dwelling depths of G. scitula and the isotopic compositions together with hydrochemistry data, the empirical relations between isotopic disequilibria in carbon (Δδ13C=δ13CG. scitula−δ13CDIC) and oxygen (Δδ18O=δ18OG. scitula−δ18Ow) isotopes in the carbonate tests and the seawater δ18O and δ13C of dissolved inorganic carbon (DIC), respectively, are introduced. The morphological information such as pore density and porosity is also examined for significant relations to carbonate chemistry. Shell porosity is strongly correlated saturation state of calcite. The dissolution of living G. scitula tests may promote the observed isotopic differences as well as the increases in porosity. Δδ18O of G. scitula is found effectively to be linear function of both water temperature and calcite saturation state (Ω), and thereby temperature equation for G. scitula is provided, while Δδ13C of G. scitula is a linear function of only calcite saturation state.The equation was validated by using Globorotalia scitula collected by a sediment trap in intermediate water depths. Satisfactory agreements were found between observed and calculated Δδ18O from the empirical equations based on temperature and hydrochemistry data at sediment trap deployment site, indicating that the equation may be useful in paleo-environmental reconstruction of sub-intermediate water. The sediment trap observation further suggests that the abundance of G. scitula does not necessarily correspond to surface water productivity and to POC flux, but instead, it correlates well with the supply of fine organic matter, which appears to be a result of water convection. Thus, G. scitula may be an unambiguous and excellent paleo-environmental recorder for carbonate chemistry and for fine organic matter transport to the depths, if isotopic and morphological observations are combined. 相似文献
18.
Hiroki Miwa Atsuko Kinoshita Hiroo Fukuda Shinichiro Sawa 《Journal of plant research》2009,122(1):31-39
The plant meristems, shoot apical meristem (SAM) and root apical meristem (RAM), are unique structures made up of a self-renewing
population of undifferentiated pluripotent stem cells. The SAM produces all aerial parts of postembryonic organs, and the
RAM promotes the continuous growth of roots. Even though the structures of the SAM and RAM differ, the signaling components
required for stem cell maintenance seem to be relatively conserved. Both meristems utilize cell-to-cell communication to maintain
proper meristematic activities and meristem organization and to coordinate new organ formation. In SAM, an essential regulatory
mechanism for meristem organization is a regulatory loop between WUSCHEL (WUS) and CLAVATA (CLV), which functions in a non-cell-autonomous manner. This intercellular signaling network coordinates the development of the
organization center, organ boundaries and distant organs. The CLAVATA3/ESR (CLE)-related genes produce signal peptides, which act non-cell-autonomously in the meristem regulation in SAM. In RAM, it has
been suggested that a similar mechanism can regulate meristem maintenance, but these functions are largely unknown. Here,
we overview the WUS–CLV signaling network for stem cell maintenance in SAM and a related mechanism in RAM maintenance. We also discuss conservation
of the regulatory system for stem cells in various plant species.
S. Sawa is the recipient of the BSJ Award for Young Scientist, 2007. 相似文献
19.
Shunsuke Kiyohara Hiroaki Honda Noriko Shimizu Chika Ejima Ryota Hamasaki Shinichiro Sawa 《Plant signaling & behavior》2011,6(9):1351-1355
Plant phytohormone, Indole-3-acetic acid (IAA ), is synthesized by tryptophan (trp) dependent and independent pathway. Here we report that tryptophan auxotroph mutants completely suppressed the abnormalities of auxin over production mutant, superroot2. SUR2 is considered to modulate Trp dependent pathway, resulting IAA accumulation in Arabidopsis. Tryptophan auxotroph mutants showed hyper-sensitivity to the auxin polar transport inhibitor, NPA, on the phenotype of reduced gravitropism. These results together with the results of histochemical analyses, tryptophan auxotroph mutants seem to have a complete defect in Trp dependent IAA biosynthesis pathway, and it is also suggested that the Trp dependent pathway is responsible for the normal root gravitropism.Key words: Auxin, Trp dependent pathway, trp mutants, sur2, arabidopsis 相似文献
20.
Kenji Takizawa Shinichiro Takahashi Norman P. A. Hüner Jun Minagawa 《Photosynthesis research》2009,99(3):195-203
Chlamydomonas raudensis Ettl UWO241, a natural variant of C. raudensis, is deficient in state transitions. Its habitat, the deepest layer of Lake Bonney in Antarctica, features low irradiance,
low temperature, and high salinity. Although psychrophily and low-light acclimation of this green alga has been described,
very little information is available on the effect of salinity. Here, we demonstrate that this psychrophile is halotolerant,
not halophilic, and it shows energy redistribution between photosystem I and II based on energy spillover under low-salt conditions.
Furthermore, we revealed that C. raudensis exhibits higher non-photochemical quenching in comparison with the mesophile Chlamydomonas reinhardtii, when grown with low-salt, which is due to the lower proton conductivity across the thylakoid membrane. Significance of the
C. raudensis UWO241 traits found in the low salinity culture are implicated with their natural habitats, including the high salinity and
extremely stable light environments. 相似文献