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951.
Anti-tumor activities of the antlered form of Ganoderma lucidum in allogeneic and syngeneic tumor-bearing mice 总被引:3,自引:0,他引:3
Nonaka Y Shibata H Nakai M Kurihara H Ishibashi H Kiso Y Tanaka T Yamaguchi H Abe S 《Bioscience, biotechnology, and biochemistry》2006,70(9):2028-2034
We investigated the anti-tumor effects of a dry powder preparation of the antlered form of Ganoderma lucidum (G. lucidum AF, rokkaku-reishi in Japanese), a variant type of G. lucidum, not only in allogeneic Sarcoma 180-bearing ddY mice, but also in syngeneic MM 46-bearing C3H/He mice. G. lucidum AF inhibited tumor growth and elongated the life span when orally administered to mice by free-feeding of a 2.5% G. lucidum AF-containing diet. It also showed anti-tumor activity in spite of post-feeding after tumor inoculation. G. lucidum AF significantly countered the depression of splenic CD8+ cells and protected the decrease in interferon-gamma (IFN-gamma) production in regional lymph nodes of MM 46-bearing mice, indicating that the anti-tumor activity of G. lucidum AF might be caused by its immunostimulating action. These results suggest that the ingestion of G. lucidum AF can be useful for the prevention and curing of cancer. 相似文献
952.
Hanawa T Suzuki K Kawauchi Y Takamura M Yoneyama H Han GD Kawachi H Shimizu F Asakura H Miyazaki J Maruyama H Aoyagi Y 《The journal of gene medicine》2006,8(5):623-635
BACKGROUND: Hepatocyte growth factor (HGF) has multiple biological effects on a wide variety of cells. It modulates intestinal epithelial proliferation and migration, and critically regulates intestinal wound healing. AIMS: To investigate the therapeutic effect of HGF gene transfer, we introduced the HGF gene into the liver of mice with acute colitis. METHODS: The rat HGF expression plasmid vector, pCAGGS-HGF, was injected via the tail vein into C57BL/6 mice, followed by dosing with dextran sulfate sodium in distilled water. Firstly, the HGF gene was injected once on day 0. Secondly, the HGF gene was injected on day 0 and again on day 2. RESULTS: Injection of the HGF gene ameliorated colitis with inhibition of both loss of body weight and shortening of colon length. It protected the colon from epithelial erosions and cellular infiltration. Expression of mRNAs for IFN-gamma, IL18, and TNF-alpha was reduced in the colon. In contrast, expression of mRNA for IL-10 was increased. The numbers of BrdU-positive intestinal epithelial cells were increased, and the numbers of TUNEL-positive apoptotic cells were decreased. Furthermore, a second injection prolonged the elevation of serum HGF levels, and ameliorated the symptoms better than a single injection. The empty pCAGGS plasmid did not ameliorate acute colitis. CONCLUSIONS: HGF gene transfer attenuated acute colitis by facilitating intestinal wound repair as well as inhibiting inflammation, suggesting a new strategy for treatment of IBD. 相似文献
953.
Wang W Adachi M Kawamura R Sakamoto H Hayashi T Ishida T Imai K Shinomura Y 《Apoptosis : an international journal on programmed cell death》2006,11(12):2225-2235
The sesquiterpene lactone, parthenolide (PTL), possesses strong anticancer activity against various cancer cells. We report
that PTL strongly induced apoptosis in 4 multiple myeloma (MM) cell lines and primary MM cells (CD38+ high), but barely induced death in normal lymphocytes (CD38−/+low). PTL-mediated apoptosis correlated well with ROS generation and was almost completely inhibited by L-N-acetylcysteine
(L-NAC), indicating the crucial role of oxidative stress in the mechanism. Among 4 MM cell lines, there is considerable difference
in susceptibility to PTL. KMM-1 and MM1S cells sensitive to PTL possess less catalase activity than the less sensitive KMS-5
and NCI-H929 cells as well as normal lymphocytes. A catalase inhibitor 3-amino-1,2,4-triazole enhanced their PTL-mediated
ROS generation and cell death. The siRNA-mediated knockdown of catalase in KMS-5 cells decreased its activity and sensitized
them to PTL. Our findings indicate that PTL induced apoptosis in MM cells depends on increased ROS and intracellular catalase
activity is a crucial determinant of their sensitivity to PTL. 相似文献
954.
Masaaki Nemoto Toshiaki Mito William S Brinigar Clara Fronticelli Raymond C Koehler 《Journal of applied physiology》2006,100(5):1688-1691
Cell-free hemoglobin solutions with high oxygen affinity might be beneficial for selectively delivering oxygen to ischemic tissue. A recombinant hybrid hemoglobin molecule was designed using the human alpha-subunit and the bovine beta-subunit, with placement of surface cysteines to permit disulfide bond polymerization of the tetramers. The resulting protein generated from an Escherichia coli expression system had a molecular mass >1 MDa, a P50 of approximately 3 Torr, and a cooperativity of n = 1.0. Anesthetized mice were transfused during 2-h occlusion of the middle cerebral artery. Compared with transfusion with 5% albumin, cerebral infarct volume was reduced by 41% with transfusion of a 3% solution of the high oxygen-affinity hemoglobin polymer and by 50% with transfusion of a 6% solution of the polymer. Transfusion of a 6% solution of a 500-kDa polymer possessing a P50 of 17 Torr and a cooperativity of n = 2.0 resulted in a 66% reduction of infarct volume. These results indicate that cell-free Hb polymers with P50 values much lower than that of red blood cell hemoglobin are highly capable of salvaging ischemic brain. The assumption that the P50 of blood substitutes should be similar to that of blood might not be warranted when used during ischemic conditions. 相似文献
955.
Ezure T Suzuki T Higashide S Shintani E Endo K Kobayashi S Shikata M Ito M Tanimizu K Nishimura O 《Biotechnology progress》2006,22(6):1570-1577
We established a novel cell-free protein synthesis system derived from Trichoplusia ni (HighFive) insect cells by a simple extraction method. Luciferase and beta-galactosidase were synthesized in this system with active forms. We analyzed and optimized (1) the preparation method of the insect cell extract, (2) the concentration of the reaction components, and (3) the 5'-untranslated region (5'-UTR) of mRNA. The extract was prepared by freeze-thawing insect cells suspended in the extraction buffer. This preparation method was a simple and superior method compared with the conventional method using a Dounce homogenizer. Furthermore, protein synthesis efficiency was improved by the addition of 20% (v/v) glycerol to the extraction buffer. Concentrations of the reaction components were optimized to increase protein synthesis efficiency. Moreover, mRNAs containing 5'-UTRs derived from baculovirus polyhedrin genes showed high protein synthesis activity. Especially, the leader composition of the Ectropis obliqua nucleopolyhedrovirus polyhedrin gene showed the highest enhancement activity among the six 5'-UTRs tested. As a result, in a batch reaction approximately 71 microg of luciferase was synthesized per milliliter of reaction volume at 25 degrees C for 6 h. Moreover, this method for the establishment of a cell-free system was applied also to Spodoptera frugiperda 21 (Sf21) insect cells. After optimizing the concentrations of the reaction components and the 5'-UTR of mRNA, approximately 45 microg/mL of luciferase was synthesized in an Sf21 cell-free system at 25 degrees C for 3 h. These productivities were sufficient to perform gene expression analyses. Thus, these cell-free systems may be a useful tool for simple synthesis in post-genomic studies as a novel protein production method. 相似文献
956.
957.
Proteomic technologies were applied to the examination of nutrient components in culture broth. In bioprocesses, many types of media have been proposed and used on the commercial scale. Natural nutrients, the chemical components of which cannot be identified completely, are often used in fermentation processes such as in the production of baker's yeast, alcoholic beverages, amino acids, and pharmaceuticals. The catabolic activities of the microorganisms in these processes vary with the species used. We used an artificial neural network (ANN) to recognize the sufficiency of chemical elements based on the protein spots resolved in 2-DE, and we evaluated this technique using the leave-one-out method. We also attempted to reduce the number of input data for spot selection based on sensitivity analysis of the ANN, and the selected data were used to improve accuracy. 相似文献
958.
959.
960.
Nakatani S Ikura M Yamamoto S Nishita Y Itadani S Habashita H Sugiura T Ogawa K Ohno H Takahashi K Nakai H Toda M 《Bioorganic & medicinal chemistry》2006,14(15):5402-5422
A series of N-benzoyl 4-aminobutyric acid hydroxamate analogs were synthesized and evaluated as matrix metalloproteinase inhibitors. Synthetic work was focused on the chemical modification of the 4-aminobutyric acid part using easily available starting materials. As such, chemical modification was carried out using commercially available starting materials such as 4-aminobutyric acid, (+)- and (-)-malic acid, and D- and L-glutamic acid derivatives. Among the compounds tested, N-[4-(benzofuran-2-yl)benzoyl] 4-amino-4S-hydroxymethylbutyric acid hydroxamates derived from L-glutamic acid demonstrated more potent inhibitory activity against MMP-2 and MMP-9 compared with the corresponding 2S-hydroxy analogs or 3S-hydroxy analogs, respectively, which were derived from (-)-malic acid. Structure-activity relationship study is presented. 相似文献