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961.
Analysis of hepatic oxidative stress status by electron spin resonance spectroscopy and imaging 总被引:6,自引:0,他引:6
Togashi H Shinzawa H Matsuo T Takeda Y Takahashi T Aoyama M Oikawa K Kamada H 《Free radical biology & medicine》2000,28(6):846-853
Real-time detection of free radicals generated within the body may contribute to clarify the pathophysiological role of free radicals in disease processes. Of the techniques available for studying the generation of free radicals in biological systems, electron spin resonance (ESR) has emerged as a powerful tool for detection and identification. This article begins with a review of spin trapping detection of oxygen-centered radicals using X-band ESR spectroscopy and then describes the detection of superoxide and hydroxyl radicals by the spin trap 5,5-dimethyl-1-pyrroline-N-oxide and ESR spectroscopy in the perfusate from isolated perfused rat livers subjected to ischemia/reperfusion. This article also reviews the current status of ESR for the in vivo detection of free radicals and in vivo imaging of exogenously administered free radicals. Moreover, we show that in vivo ESR-computed tomography with 3-carbamoyl-2,2,5, 5-tetramethylpyrrolidine-1-oxyl may be useful for noninvasive anatomical imaging and also for imaging of hepatic oxidative stress in vivo. 相似文献
962.
The Fc portion of immunoglobulin G (IgG) expresses paired oligosaccharides with microheterogeneities, which are associated with efficiencies of effector functions and with pathological states. A comparison of electrospray ionization mass spectrometry data obtained using a variety of Fc fragments derived from human and mouse IgG that do and do not retain the inter-chain disulfide bridge(s) revealed that (1) the Fc portion can be asymmetric as well as symmetric with respect to glycosylation and (2) the ratios of the individual glycoforms are different from what is expected from the random pairing. 相似文献
963.
Production of a functional ß-glucuronidase (GUS) proteinwas induced by exposure of exponentially growing yeast cellsto heat shock after transformation of the GUS gene under thecontrol of the promoter of the heat-shock gene, HSP18.2, fromArabidopsis. Yeast cyr and bcy mutations appeared to have essentiallyno effect.
1Present Address: Laboratory of Plant Molecular Biology, TheRockefeller University, 1230 York Avenue, New York, NY 10021-6399,U.S.A. 相似文献
964.
Noriko Katayama Emi Iwata Hiroaki Sakurai Tomofusa Tsuchiya Masaaki Tsuda 《Journal of neurochemistry》1993,60(3):902-907
Abstract: Administration of carbachol, noradrenaline, and bradykinin induced Egr-1 mRNA expression within 1 h in mouse neuroblastoma × rat gliomahybrid NG108–15 cells. With specific receptor antagonists, the Egr-1 inductions by carbachol and noradrenaline were shown to be mediated via cholinergic muscarinic and α2 -adrenergic receptors, respectively. At their saturation levels for Egr-1 induction, the two agonists had additive effects when added together, but no prolongation of the effect on Egr-1 induction was observed. Addition of carbachol or noradrenaline 6 h after primary stimulation with carbachol or noradrenaline did not result in secondary Egr-1 induction, probably because of receptor desensitization. On the other hand, bradykinin consistently had an additive effect on Egr-1 induction, irrespective of the time of its addition, suggesting that the signal pathways for Egr-1 induction by carbachol or noradrenaline and by bradykinin are different. Treatment of cells with pertussis toxin or cholera toxin strongly inhibited Egr-1 induction by carbachol or noradrenaline but only partially inhibited the induction by bradykinin. Thus, the signals transduced in NG108–15 cells by different neurotransmitter receptors appear to have different effects on Egr-1 induction, depending on the times of stimulation and the combinations of receptors stimulated. 相似文献
965.
Hisao Yamaguchi Keiko Hosokawa Zheng-Lin Jiang Akira Takahashi Toshitaka Ikehara Hiroshi Miyamoto 《Journal of cellular biochemistry》1993,53(1):13-20
Cell cycle progression of synchronized HeLa cells was studied by measuring labeling of the nuclei with [3H]thymidine. The progression was arrested in a chemically defined medium in which K+ was replaced by Rb+ (Rb-CDM) but was restored upon addition of insulin and/or low density lipoprotein (LDL). Cells started DNA synthesis 12 hr after addition of insulin and/or LDL, regardless of the time of arrest, suggesting their arrest early in the G1 phase. After incubation of cells in Rb-CDM containing insulin or LDL singly for 3, 6, or 9 hr, replacement of the medium by that without an addition resulted in marked delay in entry of cells into the S phase, but in its replacement by medium containing both agents, the delay was insignificant. Synthesis of bulk protein, estimated as increase in the cell volume, was not strongly inhibited. From these results we conclude that cell cycle progression of HeLa cells in K?-depleted CDM is arrested early in the G1 phase and that the arrest is due to lack of some protein(s) required for entry into the S phase that is synthesized in the early G1 phase. 相似文献
966.
967.
Hosokawa T Ono F Tsuchiya K Sato I Takeyama N Ueda S Zanusso G Takahashi H Sata T Sakudo A Suguira K Baj A Toniolo A Yoshikawa Y Onodera T 《Microbiology and immunology》2008,52(1):25-29
By immunizing Prnp-knockout mice with synthetic polypeptides, a panel of mAbs directed to bovine PrP(C) was obtained. The mAb panel was characterized by the ELISA method, where synthetic polypeptides were used for epitope mapping. Different reactivity patterns were identified. The ability of these mAbs to detect abnormal PrP(Sc) in CJD cases was studied by immunohistochemistry. All mAbs were tested for PrP(Sc) in murine, bovine, monkey and human brain tissues. Three mAbs recognized the fragmented PrP epitope in our ELISA. Antibody 1D12 was strongly reactive to ovine and squirrel monkey tissues infected with a scrapie agent, although non-reactive to scrapie-infected mouse tissues. Antibody 2D8 was clearly reactive to type-2 but not type-1 CJD human tissues. Of particular interest was the reactivity of mAb 6C4 with the inner structure of Kuru plaques (peripheral pattern) in a type-2 CJD case and mAb T2, 1D12, 2B11, 2D8, 4B5 and 6G3-2 with the central area (central pattern). The fact that different anti-PrP mAbs possess distinct staining properties suggests that the PrP(c) to PrP(Sc) conversion might involve a multiple-step process. 相似文献
968.
Tetsuya Enishi Kiminori Yukata Mitsuhiko Takahashi Ryosuke Sato Koichi Sairyo Natsuo Yasui 《PloS one》2014,9(8)
The fate of hypertrophic chondrocytes during endochondral ossification remains controversial. It has long been thought that the calcified cartilage is invaded by blood vessels and that new bone is deposited on the surface of the eroded cartilage by newly arrived cells. The present study was designed to determine whether hypertrophic chondrocytes were destined to die or could survive to participate in new bone formation. In a rabbit experiment, a membrane filter with a pore size of 1 µm was inserted in the middle of the hypertrophic zone of the distal growth plate of ulna. In 33 of 37 animals, vascular invasion was successfully interposed by the membrane filter. During 8 days, the cartilage growth plate was enlarged, making the thickness 3-fold greater than that of the nonoperated control side. Histological examination demonstrated that the hypertrophic zone was exclusively elongated. At the terminal end of the growth plate, hypertrophic chondrocytes extruded from their territorial matrix into the open cavity on the surface of the membrane filter. The progenies of hypertrophic chondrocytes (PHCs) were PCNA positive and caspase-3 negative. In situ hybridization studies demonstrated that PHCs did not express cartilage matrix proteins anymore but expressed bone matrix proteins. Immunohistochemical studies also demonstrated that the new matrix produced by PHCs contained type I collagen, osteonectin, and osteocalcin. Based on these results, we concluded that hypertrophic chondrocytes switched into bone-forming cells after vascular invasion was interposed in the normal growth plate. 相似文献
969.
Katsutoshi Ando Fumiyuki Takahashi Motoyasu Kato Norihiro Kaneko Tokuhide Doi Yuichiro Ohe Fumiaki Koizumi Kazuto Nishio Kazuhisa Takahashi 《PloS one》2014,9(7)
Background
We previously reported the role of IL-6 in a murine model of cancer cachexia and currently documented a patient in whom tocilizumab, anti-IL-6 receptor antibody, dramatically improved cachexia induced by IL-6 over-expressing lung cancer. Despite this potential to alleviate cancer cachexia, tocilizumab has not been approved for this clinical use. Therefore, preceding our planned clinical trial of tocilizumab, we designed the two studies described here to evaluate the levels of IL-6 in patients with lung cancer and the effect of tocilizumab in a murine model of human cancer cachexia.Methods
First, we measured serum IL-6 levels in patients with lung cancer and analyzed its association with cachexia and survival. Next, we examined the effect of a rodent analog of tocilizumab (MR16-1) in the experimental cachexia model.Results
Serum IL-6 levels were higher in patients with cachexia than those without cachexia. In patients with chemotherapy-resistant lung cancer, a high IL-6 serum level correlated strongly with survival, and the cut-off level for affecting their prognosis was 21 pg/mL. Meanwhile, transplantation of IL-6-expressing Lewis Lung Carcinoma cells caused cachexia in mice, which then received either MR16-1 or 0.9% saline. Tumor growth was similar in both groups; however, the MR16-1 group lost less weight, maintained better food and water intake and had milder cachectic features in blood. MR16-1 also prolonged the survival of LLC-IL6 transplanted mice (36.6 vs. 28.5 days, p = 0.016).Conclusion
Our clinical and experimental studies revealed that serum IL-6 is a surrogate marker for evaluating cachexia and the prognosis of patients with chemotherapy resistant metastatic lung cancer and that tocilizumab has the potential of improving prognosis and ameliorating the cachexia that so devastates their quality of life. This outcome greatly encourages our clinical trials to evaluate the safety and efficacy of tocilizumab treatment for patients with increased serum IL-6. 相似文献970.
Itsushi Hayashida Yoshimi Tanimoto Yuka Takahashi Toshiyuki Kusabiraki Junko Tamaki 《PloS one》2014,9(11)