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181.
To investigate the production of useful phenols from plant resources, we examined the metabolism of cinnamic acid derivatives by a wood-rotting fungus, Schizophyllum commune. Four cinnamic acid derivatives (cinnamic, p-coumaric, ferulic, and sinapic acids) were tested as substrates. Two main reactions, reduction and cleavage of the side chain, were observed. Reduction of the side chain was confirmed in cinnamic acid and p-coumaric acid metabolism. The side chain cleavage occurred in p-coumaric acid and ferulic acid metabolism but the initial reactions of these acids differed. Sinapic acid was not metabolized by S. commune. p-Hydroxybenzaldehyde accumulation was observed in the culture to which p-coumaric acid was added. This suggests that S. commune is a useful agent for transforming p-coumaric acid into p-hydroxybenzaldehyde. 相似文献
182.
Yano K Tansengco ML Hio T Higashi K Murooka Y Imaizumi-Anraku H Kawaguchi M Hayashi M 《Molecular plant-microbe interactions : MPMI》2006,19(7):801-810
Legume plants develop specialized root organs, the nodules, through a symbiotic interaction with rhizobia. The developmental process of nodulation is triggered by the bacterial microsymbiont but regulated systemically by the host legume plants. Using ethylmethane sulfonate mutagenesis as a tool to identify plant genes involved in symbiotic nodule development, we have isolated and analyzed five nodulation mutants, Ljsym74-3, Ljsym79-2, Ljsym79-3, Ljsym80, and Ljsym82, from the model legume Lotus japonicus. These mutants are defective in developing functional nodules and exhibit nitrogen starvation symptoms after inoculation with Mesorhizobium loti. Detailed observation revealed that infection thread development was aborted in these mutants and the nodules formed were devoid of infected cells. Mapping and complementation tests showed that Ljsym74-3, and Ljsym79-2 and Ljsym79-3, were allelic with reported mutants of L. japonicus, alb1 and crinkle, respectively. The Ljsym82 mutant is unique among the mutants because the infection thread was aborted early in its development. Ljsym74-3 and Ljsym80 were characterized as mutants with thick infection threads in short root hairs. Map-based cloning and molecular characterization of these genes will help us understand the genetic mechanism of infection thread development in L. japonicus. 相似文献
183.
Song HS Lan Phi NT Park YH Sawamura M 《Bioscience, biotechnology, and biochemistry》2006,70(3):737-739
A comparison of the volatile profiles between Korean and Japanese Shiranui cold-pressed peel oil was performed by GC and GC-MS. Limonene was the most abundant in the Japanese (91.8%) and Korean (86.4%) oil. Alcohols accounted for 1.8% in the Korean oil, and 0.2% in the Japanese oil, in which the respective linalool levels were 1.2% and 0.1%. The level of aldehydes was also higher in the Korean oil (1.6%) than in the Japanese oil (0.7%). 相似文献
184.
Effects of inducible nitric oxide synthase inhibitors on asthma depending on administration schedule
Abe M Hayashi Y Murai A Shibata K Sakata N Igarashi R Katsuragi T Tanaka K 《Free radical biology & medicine》2006,40(6):1083-1095
The effectiveness of two inducible nitric oxide synthase (iNOS) inhibitors on allergic airway inflammation was investigated under different administration schedules. Rats sensitized to ovalbumin (OVA) were exposed to OVA for 3 consecutive days. Both iNOS inhibitors showed markedly different effects between two pretreatment schedules: pretreatment before each of three OVA exposures S1 and before the third exposure alone S2. S1 pretreatment resulted in higher pulmonary resistance than triple OVA alone. This potentiation was associated with increased eosinophil infiltration and malondialdehyde levels in the lungs, which were suppressed by superoxide dismutases (SODs) but not by methylprednisolone. However, the S2 administration of both iNOS inhibitors completely suppressed the airway response. Administration by schedule S1 completely suppressed plasma nitrite and nitrate levels, but that by S2 caused only a slight suppression. The triple OVA exposures resulted in the upregulation of iNOS in alveolar macrophages and arginase activity, Mn- and Cu/Zn-SOD expression, and nitrotyrosine and lipid peroxide deposition in the airway. However, inhibitors administered by schedule S1 suppressed this upregulation, but further potentiated nitrotyrosine, which in turn was inhibited by SOD. Although iNOS inhibitors may be beneficial for asthma, repeated administration may be detrimental because of extensive reduction of NO and downregulation of SOD. 相似文献
185.
Research suggests that abnormal coordination patterns between the thorax and pelvis in the transverse plane observed in patients with Parkinson's disease and the elderly might be due to alteration in axial trunk stiffness. The purpose of this study was to develop a tool to estimate axial trunk stiffness during walking and to investigate its functional role. Fourteen healthy young subjects participated in this study. They were instructed to walk on the treadmill and kinematic data was collected by 3D motion analysis system. Axial trunk stiffness was estimated from the angular displacement between trunk segments and the amount of torque around vertical axis of rotation. The torque due to arm swing cancelled out the torque due to the axial trunk stiffness during walking and the thoracic rotation was of low amplitude independent of changes in walking speeds within the range used in this study (0.85-1.52 m/s). Estimated axial trunk stiffness increased with increasing walking speed. Functionally, the suppression of axial rotation of thorax may have a positive influence on head stability as well as allowing recoil between trunk segments. Furthermore, the increased stiffness at increased walking speed would facilitate the higher frequency rotation of the trunk in the transverse plane required at the higher walking speeds. 相似文献
186.
Regulation of fibroblast growth factor-23 signaling by klotho 总被引:20,自引:0,他引:20
Kurosu H Ogawa Y Miyoshi M Yamamoto M Nandi A Rosenblatt KP Baum MG Schiavi S Hu MC Moe OW Kuro-o M 《The Journal of biological chemistry》2006,281(10):6120-6123
The aging suppressor gene Klotho encodes a single-pass transmembrane protein. Klotho-deficient mice exhibit a variety of aging-like phenotypes, many of which are similar to those observed in fibroblast growth factor-23 (FGF23)-deficient mice. To test the possibility that Klotho and FGF23 may function in a common signal transduction pathway(s), we investigated whether Klotho is involved in FGF signaling. Here we show that Klotho protein directly binds to multiple FGF receptors (FGFRs). The Klotho-FGFR complex binds to FGF23 with higher affinity than FGFR or Klotho alone. In addition, Klotho significantly enhanced the ability of FGF23 to induce phosphorylation of FGF receptor substrate and ERK in various types of cells. Thus, Klotho functions as a cofactor essential for activation of FGF signaling by FGF23. 相似文献
187.
Hydrodynamic-based delivery of an interleukin-22-Ig fusion gene ameliorates experimental autoimmune myocarditis in rats 总被引:5,自引:0,他引:5
Chang H Hanawa H Liu H Yoshida T Hayashi M Watanabe R Abe S Toba K Yoshida K Elnaggar R Minagawa S Okura Y Kato K Kodama M Maruyama H Miyazaki J Aizawa Y 《Journal of immunology (Baltimore, Md. : 1950)》2006,177(6):3635-3643
IL-22 is one of several cytokines with limited homology to IL-10. However, the biological activities of IL-22 are mostly unknown. The purpose of this study was to evaluate the effect of IL-22 on rat experimental autoimmune myocarditis (EAM) and elucidate an aspect of the biological activities of IL-22. Rats were immunized on day 0; IL-22-Ig-treated rats were injected with pCAGGS-IL-22-Ig and control rats with pCAGGS-Ig using hydrodynamics-based gene delivery on day 1 or day 6. IL-22-Ig gene therapy administered on day 1 or day 6 after immunization was effective in controlling EAM as monitored by the heart weight to body weight ratio, and the myocarditis area in rats was sacrificed on day 17. Examination of the expression of IL-22-related genes in purified cells from EAM hearts suggested that IL-22-Ig acting target cells were noncardiomyocytic (NC) noninflammatory cells such as fibroblasts, smooth muscle cells, and endothelial cells. Therefore, we examined the effect of rIL-22 or serum containing IL-22-Ig on the expression of immune-relevant genes in IL-1-stimulated NC cells cultured from EAM hearts. Results showed that the expression of immunologic molecules (PGE synthase, cyclooxygenase-2, MIP-2, MCP-1, IL-6, and cytokine-induced neutrophil chemoattractant-2) in IL-1-stimulated NC cells was significantly decreased by rIL-22 or serum containing IL-22-Ig. EAM was suppressed by hydrodynamics-based delivery of plasmid DNA encoding IL-22-Ig, and the reason for this effectiveness may be that IL-22 suppressed gene expression of PG synthases, IL-6, and chemokines in activated NC noninflammatory cells. 相似文献
188.
Hishima T Oyaizu N Fujii T Tachikawa N Ajisawa A Negishi M Nakamura T Iwamoto A Hayashi Y Matsubara D Sasao Y Kimura S Kikuchi Y Teruya K Yasuoka A Oka S Saito K Mori S Funata N Sata T Katano H 《Microbes and infection / Institut Pasteur》2006,8(5):1301-1307
Recent introduction of highly active antiretroviral therapy (HAART) is reported to have reduced the incidence of lymphoma among HIV-infected individuals. A clinicopathological study was performed on 86 AIDS-related lymphoma patients who were treated in Tokyo area from 1987 to 2005. The incidence of lymphoma detected by autopsy was 27% (53 cases/198 autopsies). Diffuse large B cell lymphoma was the most predominant histological subtype throughout the period (78%). Burkitt's lymphoma (BL) increased from 2% in the pre-HAART era (before end-1997) to 13% in the HAART era, whereas incidence of BL did not vary between HAART users and non-users. Epstein-Barr virus (EBV)-positive lymphoma decreased from 88% in the pre-HAART era to 58% in the HAART era, but did not differ significantly between HAART users (73%) and non-users (74%). Nodal involvement of lymphoma increased from 14% in the pre-HAART era to 50% in the HAART era; however, central nervous system involvement decreased from 62 to 38%. Kaposi's sarcoma-associated herpesvirus infection was rare (4%) among all cases. These data suggest that HAART might play a partial role in these changes, and the alteration in immunological backgrounds, such as EBV prevalence, is suggested as another leading cause of these changes in Japanese AIDS-related lymphoma. 相似文献
189.
This paper describes courtship of Drosophila quadrilineata of the immigrans group and reports a species-specific element, abdomen bending, that has not been described in Drosophila. The male bends his abdomen right and left as a display to the female. During courtship the male circles around the female, bends his abdomen, and taps her. The male licks the female ovipositor repeatedly, often after the females extrusion. Although the females ovipositor extrusion is thought to indicate rejection of a courting male in many species, the male of D. quadrilineata continues courtship. It is possible that the extrusion is a females mating signal to the courting male. The male of D. quadrilineata mounts the female in a rearward position and the genitalia of both sexes couple after mounting. This mounting position is shared by the species belonging to the immigrans group. We never observed behavior in which it appeared as if the male displayed the black stripes to the female. Males court one another and a courtship chain is frequently formed even in the absence of females. The males abdomen bending and the females extrusion followed by the males licking are discussed. 相似文献
190.
Tokita M 《Journal of morphology》2006,267(3):333-340
Parrots have developed unique jaw muscles in their evolutionary history. The M. pseudomasseter, which completely covers the lateral side of the jugal bar, is regarded as a jaw muscle unique to parrots. In a previous study, I presented a hypothesis on the relevance of modifications in the regulation of cranial neural crest cell (NCC) development to the generation of this novel jaw muscle based on histological analyses (Tokita [2004] J Morphol 259:69-81). In the present study, I investigated distribution and migration patterns of cranial neural crest cells (NCCs) through parrot embryogenesis with immunohistochemical techniques to further understand the role of cranial NCCs in the evolution of the M. pseudomasseter, and to provide new information on the relative plasticity in cranial NCC migration at early stages of avian development. The basic nature of cranial NCC development was mostly conserved between chick and parrot. In both, cranial NCCs migrated from the dorsal tip of the neural tube in a ventral direction. Three major populations were identified in their cranial NCCs. Migration pathways of these cells were almost identical between chick and parrot. The principal difference was seen in the relative timing of cranial NCC migration. In the parrot, cranial NCC migration into the first pharyngeal arch was more advanced than in the chick at early stages of development. Such a temporal shift in cranial NCC migration might influence architectural patterning of parrot jaw muscles that generates new muscle like M. pseudomasseter. 相似文献