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61.
Primates often modify dietary composition in relation to seasonal changes in food availability or climate conditions. We studied the feeding patterns of a troop of common brown lemurs (Eulemur fulvus), a semi-frugivorous strepsirhine, in a dry forest in northwestern Madagascar. To understand the mechanism of dietary modification, we recorded daily feeding times of diet items during 101 full-day observations over 1 year, and then conducted a linear model analysis to examine the effects of fruiting tree density in the forest, daily ambient temperature, and weekly rainfall (index of water retained in the forest) on the lemurs' daily feeding time. The lemurs spent dramatically more time on leaf-eating as well as total feeding time, and less time on fruit-eating during the late dry season (total 152 min/day, frugivory 56 min/day, folivory 77 min/day), as compared with other seasons when the diet was highly frugivorous (total 96 min/day, frugivory 81 min/day, folivory 8 min/day). Folivory increased as temperatures rose under the condition of low weekly rainfall, whereas frugivory was unrelated to fruiting tree density. Most (97.4 %) diurnal folivory during the late dry season was spent consuming Lissochilus rutenbergianus, chewing the succulent leaves and licking the juice. Because the nutritional analysis showed that L. rutenbergianus is rich in water (80.1 % of fresh weight) but poor in protein and nonstructural carbohydrates, its increased use was probably for rehydration. We conducted 13 full-night observations, because brown lemurs increase nocturnal activities during the dry season. At nighttime, the lemurs tended to spend more time eating fruit in the late dry season (32 min/night) than in the early dry season (14 min/night), and never consumed L. rutenbergianus. Fruits rich in nonstructural carbohydrates can be energy sources for Eulemur. They likely engaged in additional nocturnal frugivory for energy compensation. Brown lemurs have a flexible strategy of modifying their diet and feeding activities to cope with environmental stresses. 相似文献
62.
Tokuo Ogawa Junichi Sugenoya Norikazu Ohnishi Keiko Natsume Megumi Ochiai Motohiko Nishida Norihiko Shinoda Kenichi Katoh Ritsuko Imamura 《International journal of biometeorology》1991,35(1):18-23
In an attempt to detect differences in the thermal effect of infrared irradiation of different wavelengths, transient sweating response to infrared irradiation in various spectral regions was examined. In Series 1, the ventral or dorsal surface of the nude subject was irradiated repetitively for a period of 4 min (2 min on, 2 min off) by each of three kinds of infrared heaters with main emissivity in near-infrared (NIR; 0.7–2.8 m), intermediate-infrared (MIR; 1.5–5.8 m), and far-infrared (FIR; 2.8–25 m) regions. The sweating response on a non-irradiated area tended to be the greatest with MIR, while the magnitude of the sweating response on the irradiated area showed no consistent differences among various wavelengths. The results infer that MIR stimulated cutaneous thomoreceptors most effectively, while its direct effect on local sweat gland activity was minimal. In Series 2, the effects of 9–12 min irradiations in more restricted ranges of wavelength were compared by the combination of the three kinds of heaters with filters (translucent to wavelength ranges of 1.3–2.7, 2.7–3.5, 3.6–8.0 m, respectively). The sweating response on a remote area was predominantly greater with the range of 2.7–3.5 m than with the other wavelength ranges, while the local effect on sweating was minimal with this range. The results of Series 2 reinforce those of Series 1, indicating that the degree of stimulation of cutaneous thermoreceptors and of direct thermal effect on sweat gland activity differ with spectral regions incident on the skin, thus affecting local and remote effects on the sweating response. 相似文献
63.
Level of translatable messenger RNA coding for argininosuccinate synthetase in the liver of the patients with quantitative-type citrullinemia 总被引:2,自引:0,他引:2
Mariko Sase Keiko Kobayashi Yasushi Imamura Takeyori Saheki Kyoko Nakano Satoshi Miura Masataka Mori 《Human genetics》1985,69(2):130-134
Summary The translation activity of mRNA coding for argininosuccinate synthetase in total RNA extracted from the liver of three patients with quantitative-type citrullinemia was determined using a cell-free translation system. In two patients, the hepatic content of the enzyme was about 20% of the control value, whereas translatable mRNA level for the enzyme was similar to or slightly lower than those of control livers. In the third patient, the enzyme content was about 50% of the control value, and mRNA activity for the enzyme was low normal. These results indicate that at least in the first two patients, the decrease in the enzyme protein is due either to increased degradation of the enzyme or to decreased translation in the patient's liver. 相似文献
64.
Kenji Nomiya Kuniaki Onodera Ken Tsukagoshi Kouhei Shimada Akira Yoshizawa Tada-aki Itoyanagi Akiyoshi Sugie Shinichiro Tsuruta Ryo Sato Noriko Chikaraishi Kasuga 《Inorganica chimica acta》2009,362(1):43-55
Metal-oxygen bonding complexes (M = MgII, MnII, NiII, MoVI, WVI, PdII, SbIII, BiIII, FeIII, TiIV, KI, BaII, ZrIV and HfIV) with a hinokitiol (Hhino; 2-hydroxy-4-isopropylcyclohepta-2,4,6-trienone or β-thujaplicin) ligand, which has two unequivalent oxygen donor atoms, were synthesized and characterized by elemental analysis, TG/DTA, FT-IR and solution (1H and 13C) NMR spectroscopy. Single-crystal X-ray structure analysis revealed various molecular structures for the complexes, which were classified into several families of family, i.e. type A [MII(hino)2(L)]2 (M = MgII, MnII, NiII; L = EtOH or MeOH), with a dimeric structure consisting of one bridging hino− anion, one chelating hino− anion and one alcohol or water molecule, type B, with the octahedral, cis-dioxo, bis-chelate complexes cis-[MVIO2(hino)2] (M = MoVI, WVI), type C, with square planar complex [MII(hino)2] (M = PdII), type D, with tris-chelate, 7-coordinate complexes with one inert electron pair [MIII(hino)3] (M = SbIII, BiIII), type D′, with the bis-chelate, pseudo-6-coordinate complexes with one inert electron pair [MIII(hino)2X] (M = SbIII, X = Br), type E, with tris-chelate, 6-coordinate complexes with Δ and Λ isomers [MIII(hino)3] (M = FeIII), type E′ of bis-chelate, 6-coordinate complex [MIV(hino)2X2] (M = TiIV, X = Cl), type F, with water-soluble alkali metal salts [MI(hino)] (M = KI), and type H, with tetrakis-chelate, 8-coordinate complexes [MIV(hino)4](M = ZrIV, HfIV). These structural features were compared with those of metal complexes with a related ligand, tropolone (Htrop). The antimicrobial activities of these complexes, evaluated in terms of minimum inhibitory concentration (MIC; μg mL−1) in two systems, were compared to elucidate the relationship between structure and antimicrobial activity. 相似文献
65.
Yasuhiro Suzuki Chandra Nath Roy Warunya Promjunyakul Hiroyasu Hatakeyama Kohsuke Gonda Junji Imamura Biju Vasudevanpillai Noriaki Ohuchi Makoto Kanzaki Hideo Higuchi Mitsuo Kaku 《Molecular and cellular biology》2013,33(15):3036-3049
The mechanisms underlying the cellular entry of the HIV-1 Tat protein transduction domain (TatP) and the molecular information necessary to improve the transduction efficiency of TatP remain unclear due to the technical limitations for direct visualization of TatP''s behavior in cells. Using confocal microscopy, total internal reflection fluorescence microscopy, and four-dimensional microscopy, we developed a single-molecule tracking assay for TatP labeled with quantum dots (QDs) to examine the kinetics of TatP initially and immediately before, at the beginning of, and immediately after entry into living cells. We report that even when the number of multivalent TatP (mTatP)-QDs bound to a cell was low, each single mTatP-QD first locally induced the cell''s lateral transport machinery to move the mTatP-QD toward the center of the cell body upon cross-linking of heparan sulfate proteoglycans. The centripetal and lateral movements were linked to the integrity and flow of actomyosin and microtubules. Individual mTatP underwent lipid raft-mediated temporal confinement, followed by complete immobilization, which ultimately led to endocytotic internalization. However, bivalent TatP did not sufficiently promote either cell surface movement or internalization. Together, these findings provide clues regarding the mechanisms of TatP cell entry and indicate that increasing the valence of TatP on nanoparticles allows them to behave as cargo delivery nanomachines. 相似文献
66.
Takahashi S Harigae H Kaku M Sasaki T Licht JD 《Biochemical and biophysical research communications》2004,315(1):85-92
Metastin, a post-translationally modified variant of KiSS1, was recently identified as an endogenous peptide agonist for a novel G-protein coupled receptor, hOT7T175 (AXOR12, GPR54). In this study, we analyzed the role of KiSS1 and hOT7T175 in both pancreatic cancer tissues and pancreatic cancer cell lines. Furthermore, we synthesized novel short variant forms of metastin and tested the inhibitory effect of those variants on in vitro cell functions that are relevant to metastasis. Pancreatic cancer tissues showed significantly lower expression of KiSS1 mRNA than normal tissues (p=0.018), while cancer tissues showed significantly higher expression of hOT7T175 mRNA than normal pancreatic tissues (p=0.027). In human pancreatic cancer cell lines, KiSS1 mRNA was highly expressed in 2 out of 6 pancreatic cancer cell lines, while hOT7T175 mRNA was expressed in all cell lines at various degrees. PANC-1 cells showed the highest expression of hOT7T175. Exogenous metastin did not suppress cell proliferation but significantly reduced the in vitro migration of PANC-1 cells (p<0.01). Metastin induced activation of ERK1 in PANC-1 and AsPC-1 cells. Finally, we synthesized 3 novel short variant forms of metastin, FM053a2TFA, FM059a2TFA, and FM052a4TFA. These metastin variants significantly suppressed the migration of PANC-1 cells and activated ERK1. These data suggest that the metastin receptor, hOT7T175, is one of the promising targets for suppression of metastasis, and that small metastin variants could be an anti-metastatic agent to pancreatic cancer. 相似文献
67.
Nuki Y Uchinokura S Miyata S Fukushima T Hamasuna R Nakano S Wakisaka S Akiyama Y Itoh H Kataoka H 《Human cell》2004,17(3):145-150
A cell line designated NYGM was established from a human cerebral glioblastoma multiforme (GBM) obtained from a 75-year-old Japanese woman. The cell line has grown slowly without interruption and has been propagated continuously by serial passages (more than 80 passage) during the past 3 years. The cultured cells were fusiform or polyhedral in shape. The population doubling time was 24 hours. The chromosomal number varied between 77 and 88, with modal chromosomal number of 84. NYGM cells concomitantly expressed MET receptor tyrosine kinase (a product of c-met protooncogene) and its ligand HGF/SF (hepatocyte growth factor/scatter factor), as well as HGF activator and HGF activator inhibitors. The cells might be useful for the study of pericellular regulation of HGF/SF-MET signaling and HGF activation of GBM cells. 相似文献
68.
Wang ST Setlow B Conlon EM Lyon JL Imamura D Sato T Setlow P Losick R Eichenberger P 《Journal of molecular biology》2006,358(1):16-37
Endospore formation by Bacillus subtilis involves three differentiating cell types, the predivisional cell, the mother cell, and the forespore. Here we report the program of gene expression in the forespore, which is governed by the RNA polymerase sigma factors sigma(F) and sigma(G) and the DNA-binding proteins RsfA and SpoVT. The sigma(F) factor turns on about 48 genes, including the gene for RsfA, which represses a gene in the sigma(F) regulon, and the gene for sigma(G). The sigma(G) factor newly activates 81 genes, including the gene for SpoVT, which turns on (in nine cases) or stimulates (in 11 cases) the expression of 20 genes that had been turned on by sigma(G) and represses the expression of 27 others. The forespore line of gene expression consists of many genes that contribute to morphogenesis and to the resistance and germination properties of the spore but few that have metabolic functions. Comparative genomics reveals a core of genes in the sigma(F) and sigma(G) regulons that are widely conserved among endospore-forming species but are absent from closely related, but non-spore-forming Listeria spp. Two such partially conserved genes (ykoU and ykoV), which are members of the sigma(G) regulon, are shown to confer dry-heat resistance to dormant spores. The ykoV gene product, a homolog of the non-homologous end-joining protein Ku, is shown to associate with the nucleoid during germination. Extending earlier work on gene expression in the predivisional cell and the mother cell, we present an integrated overview of the entire program of sporulation gene expression. 相似文献
69.
70.
Hideki Yoshida Toshihiko Imamura Akiko M. Saito Yoshihiro Takahashi So-ichi Suenobu Daiichiro Hasegawa Takao Deguchi Yoshiko Hashii Hirohide Kawasaki Mikiya Endo Hiroki Hori Nobuhiro Suzuki Yoshiyuki Kosaka Koji Kato Keiko Yumura-Yagi Junichi Hara Megumi Oda Atsushi Sato Keizo Horibe Japan Association of Childhood Leukemia Study 《PloS one》2015,10(8)
Although L-asparaginase related hyperglycemia is well known adverse event, it is not studied whether the profile of this adverse event is affected by intensification of L-asparaginase administration. Here, we analyzed the profile of L-asparaginase related hyperglycemia in a 1,176 patients with pediatric acute lymphoblastic leukemia treated according to the Japan Association of Childhood Leukemia Study ALL-02 protocol using protracted L-asparaginase administration in maintenance phase. We determined that a total of 75 L-asparaginase related hyperglycemia events occurred in 69 patients. Although 17 events (17/1176, 1.4%) developed in induction phase, which was lower incidence than those (10–15%) in previous reports, 45 events developed during the maintenance phase with protracted L-asparaginase administration. Multivariate analysis showed that older age at onset (≥10 years) was a sole independent risk factor for L-asparaginase-related hyperglycemia (P<0.01), especially in maintenance phase. Contrary to the previous reports, obesity was not associated with L-asparaginase-related hyperglycemia. These findings suggest that protracted administration of L-asparaginase is the risk factor for hyperglycemia when treating adolescent and young adult acute lymphoblastic leukemia patients. 相似文献