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1.
Galectin-3 is a β-galactoside-binding C-type lectin that plays an important role in innate immunity. The purpose of this study was to determine whether Candida albicans and Candida parapsilosis up-regulate galectin-3 secretion by human gingival epithelial cells and gingival fibroblasts. Ca9-22, a human gingival epithelial cell line, and human gingival fibroblasts were incubated in the presence or absence of C. albicans or C. parapsilosis without serum. Levels of secreted human galectin-3 in culture supernatants were measured by enzyme-linked immunosorbent assay. We also pretreated Ca9-22 cells with cytochalasin D (an actin polymerization inhibitor), ALLN (a calpain inhibitor) and LY294002 [a phosphatidylinositol-3 kinase (PI3K) inhibitor] to determine whether the up-regulation of galectin-3 secretion was mediated by cytoskeletal changes, protease activity, or PI3K signaling. Galectin-3 secretion was significantly and rapidly up-regulated by live C. albicans and C. parapsilosis, as well as heat-killed C. albicans. In addition, cytochalasin D, LY294002 and ALLN did not inhibit the up-regulation in galectin-3 secretion. These results suggest that both live and heat-killed C. albicans and C. parapsilosis may increase the activity of the innate immune system and invasion by other microorganisms via up-regulation of galectin-3 secretion. 相似文献
2.
The development of mitochondrial NAD+ -malate dehydrogenase (EC 1.1.1.37) in mung bean and cucumber cotyledons was followed. using the antibody raised against it, during and following germination. The developmental patterns were quite different between the two. In cucumber, the content of mitochondrial malate dehydrogenase continued to increase through 3–4 days after the beginning of imbibition. This was, at least in part, due to active synthesis of the enzyme protein, and the synthesis seemed to be regulated by the availability of the translatable mRNA for the enzyme. In mung bean, on the other hand, the enzyme was present in dry cotyledons at a rather high concentration, and remained at a constant level between day 1 and day 3 after the reduction of the content to one-half its initial level during the first day. De novo synthesis of the enzyme could not be detected in mung bean cotyledons by pulse-labeling experiment. 相似文献
3.
4.
H Yasuda M Miki Y Takenaka H Tamai M Mino 《Archives of biochemistry and biophysics》1989,272(1):81-87
The oxidation of vitamin E-deficient rat red blood cells (RBCs) induced by the hypoxanthine-xanthine oxidase (HX-XOD) system has been performed in an aqueous suspension. The generation of chemiluminescence and the accumulation of thiobarbituric acid-reactive substances (TBARS) were observed initially and were followed by hemolysis. Interestingly, the total counts of chemiluminescence were closely related to the amount of TBARS. The predominant change of membrane proteins induced by the reaction was the depletion of spectrin bands in gel electrophoresis. When RBC ghosts were oxidized with HX-XOD, the sulfhydryl (SH) groups of membrane proteins decreased at an early stage of the incubation, which was coincident with the above protein alteration. Membrane alpha-tocopherol suppressed not only the formation of TBARS but also chemiluminescence and hemolysis; nevertheless, it did not inhibit the protein damage and the loss of SH groups. Moreover, it was concluded that the chemiluminescence observed during the oxidation of RBC membranes was associated mainly with the peroxidation of lipids and only to a minor extent with the oxidation of proteins. 相似文献
5.
Primary photoprocesses of phytochrome. Picosecond fluorescence kinetics of oat and pea phytochromes 总被引:2,自引:0,他引:2
P S Song B R Singh N Tamai T Yamazaki I Yamazaki S Tokutomi M Furuya 《Biochemistry》1989,28(8):3265-3271
The primary photoprocesses of etiolated oat and pea phytochromes (Pr forms) are diffusion-modulated by the microscopic viscosity within the chromophore pocket. The chromophore pocket is preferentially accessible to glycerol but not to Ficoll. Glycerol preferentially retarded the rate (rate constant ca. 1-2 X 10(10) s-1) of the initial reaction from the Qy excited state of phytochrome, whereas it increased the long fluorescence lifetime (nanosecond) component that can be attributed to either an emitting intermediate or to modified/conformationally heterogeneous phytochrome populations. The picosecond time-resolved fluorescence spectra of different phytochrome preparations (i.e., full-length vs 6/10-kDa NH2-terminus truncated forms of phytochromes from monocot and dicot plants) revealed no significant differences. The spectra in the picosecond time scale showed no spectral shifts, but at longer time scales of up to approximately 1.90 ns, significant blue spectral shifts were observed. The shifts were more in the truncated than in the full-length pea phytochrome. Comparison of the fluorescence decay data and the picosecond time-resolved fluorescence spectra suggests differences in conformational flexibility/heterogeneity among the preparations of the monocot vs dicot phytochromes and the full-length native vs the amino terminus truncated phytochromes. 相似文献
6.
Detection of point mutation in the tyrosinase gene of a Japanese albino patient by a direct sequencing of amplified DNA 总被引:7,自引:1,他引:6
Hideaki Kikuchi Satoshi Hara Seiichi Ishiguro Makoto Tamai Minro Watanabe 《Human genetics》1990,85(1):123-124
Summary Enzymatic DNA amplification and direct DNA sequencing were used to detect a mutation in the tyrosinase gene of an albino patient. Single-base change could be detected by direct sequencing. This base change (G to A) is thought to result in an amino acid change (Arg to Gln) in tyrosinase of the patient. 相似文献
7.
Studies on DNA markers (D4S10 and D4S43/S127) genetically linked to Huntington's disease in Japanese families 总被引:1,自引:0,他引:1
Ichiro Kanazawa Ikuko Kondo Joh-E Ikeda Teruaki Ikeda Yuichior Shizu Mitsuo Yoshida Hirotaro Narabayashi Shigetoshi Kuroda Hisayuki Tsunoda Eiji Mizuta Yoko Okuno Kiyotaka Sugawara Miho Murata Mafuyu Takahashi James F. Gusella 《Human genetics》1990,85(3):257-260
Summary This is the first full report on the genetic linkage between Japanese Huntington's disease and the DNA markers D4S10 and D4S43/S127. With use of the HindIII, BglI, and EcoRI polymorphisms detected at D4S10, and the combination of all these polymorphisms to give composite haplotypes, nine Japanese Huntington's disease families were found to be informative. Three recombinants for D4S10 were detected in these families, giving a maximum lod score of 1.662 at a of 0.10. Similarly, when we used the MspI and PvuII polymorphisms detected by D4S43/S127, five families gave informative results. No recombinant was detected in these families, giving a maximum lod score of 3.348 at a of 0.00. These results clearly support the view that the Japanese Huntington's disease gene may be identical with the Western gene, in spite of the lower prevalence rate in Japan. 相似文献
8.
Hiroki Yamaue Hiroshi Tanimura Takuya Tsunoda Makoto Iwahashi Masaji Tani Mikiko Tamai Masaya Inoue 《Biotherapy》1990,2(3):247-259
The tumor-infiltrating lymphocytes (TILs) were cultured with interleukin 2 (IL-2) to induce the activated killer cells possessing autologous tumor-killing activity, and analysed their cell surface phenotypes and assessed anti-tumor killing activity. Furthermore, the activated TILs were transferred into 7 patients adoptively resulting in complete remission in a patient with pancreatic cancer and partial remission in another patient with gastric cancer.The cytotoxic activities of activated TILs at 3 weeks-incubation was 72 ± 15, 42 ± 26, 27 ± 21 and 25 ± 15% against K562, Daudi, KATO-III and autologous tumor, respectively. The negative selection method, indicated that the killer cells recognizing autologous tumor cells consisted of CD4- or CD8-positive T lymphocytes and CD16- or CD56-positive natural killer cells. The activated TILs could not only lyse cultured tumor cell lines, but also autologous tumor cells. 相似文献
9.
Shoot cultures of Glehnia littoralis F. Schmidt ex Miq. (Umbelliferae) were established by placing shoot tip explants on Linsmaier and Skoog medium with 1 M NAA and 10 M BAP. Shoots were multiplied on the basal medium supplemented with 0.3 M NAA and 3 M BAP and rooted on medium containing either 1 M IBA or 3–10 M IAA. Plantlets survived in pots without any covering. This unique characteristic of the plantlets was ascribed partly to a well-developed cuticle on the surface of the leaf and the small ratio of surface area to fresh weight of a leaf blade in comparison with those of other species whose plantlets needed coverings after potting. The regenerated plantlets were finally transferred to soil.Abbreviations IAA
potassium indole-3-acetate
- IBA
indole-3-butyric acid
- IPA
indole-3-propionic acid
- NAA
potassium 1-naphthaleneacetate
- 2,4-D
sodium 2,4-dichlorophenoxyacetate
- BAP
6-benzylaminopurine
- 2-iP
N6-(2-isopentenyl)adenine 相似文献
10.
Complete nucleotide sequence of the mitochondrial DNA from a liverwort,Marchantia polymorpha 总被引:1,自引:1,他引:0
Kenji Oda Katsuyuki Yamato Eiji Ohta Yasukazu Nakamura Miho Takemura Naoko Nozato Kinya Akashi Takeshi Kanegae Yutaka Ogura Takayuki Kohchi Kanji Ohyama 《Plant Molecular Biology Reporter》1992,10(2):105-163
Libraries of cosmid and plasmid clones covering the entire region of mtDNA from the liverwortMarchantia polymorpha were constructed. These clones were used for the determination of the complete nucleotide sequence of the liverwort mtDNA
totally 186,608 bp (GenBank no. M68929) and including genes for 3 species of ribosomal RNAs, 29 genes for 27 species of transfer
RNAs, and 30 genes for functionally known proteins (16 ribosomal proteins, 3 subunits of cytochromec oxidase, apocytochromeb protein, 3 subunits of H+-ATPase, and 7 subunits of NADH ubiquinone oxidoreductase). The genome also contains 32 unidentified open reading frames.
Thus the complete nucleotide sequences from both chloroplast and mitochondrial genomes have been determined in the same organism.
Plasmid clones are available upon the request.
Gene names are represented according to Lonsdale and Leaver (1988) with modifications recommended by Lonsdale (personal communication). 相似文献