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171.
Differential expression of tissue factor and tissue factor pathway inhibitor in metastatic melanoma lesions 总被引:3,自引:0,他引:3
Kageshita T Funasaka Y Ichihashi M Ishihara T Tokuo H Ono T 《Pigment cell research / sponsored by the European Society for Pigment Cell Research and the International Pigment Cell Society》2002,15(3):212-216
Tissue factor (TF) is involved in tumor progression and metastatic potency in some malignant tumors and its function is regulated by tissue factor pathway inhibitor (TFPI) therefore the interaction of both molecules is crucial for their functional role. We evaluated the clinical relevance of TF and TFPI expression in benign and malignant melanocytic lesions. Expression of both was examined by immunoperoxidase staining using serial tissue sections in 16 nevi, 34 primary and 15 metastatic melanoma lesions. TF and TFPI were ubiquitously expressed in benign and malignant melanocytic lesions. This finding was confirmed by Western blot analysis using cultured human melanocytes, nevi cells (NCN) and melanoma cell lines. Although TF expression was not associated with malignant transformation and disease progression, TFPI expression in primary and metastatic melanoma lesions was significantly lower and weaker than that in nevi lesions in terms of intensity and percentage of stained cells. In addition, TFPI expression in metastatic lesions was significantly lower and weaker than that of TF. These results suggest that the relative expression of TF to TFPI may play a crucial role in the malignant transformation and metastatic potency in melanocytic cells. 相似文献
172.
Isolation of three main sericin components from the cocoon of the silkworm,Bombyx mori 总被引:1,自引:0,他引:1
To characterize the sericin components of the cocoon of silkworm Bombyx mori, fresh cocoon shells were dissolved in saturated aqueous lithium thiocyanate containing 2-mercaptoethanol, and fractionated by ethanol precipitation. Cocoon sericin was found to mainly consist of three polypeptides having molecular masses of the 400, 250, and 150 kDa estimated by SDS-PAGE, which corresponds to the sericin present in the middle, anterior, and posterior part of the middle silk gland. The amino acid compositions of the 400 and 150 kDa components were similar to each other, but that of the 250 kDa component was different. This suggests differences in the coding gene and properties of the 250 kDa sericin from the other two. 相似文献
173.
Ichiro Tayasu Toshio Nakamura Hirotaka Oda Fujio Hyodo Yoko Takematsu Takuya Abe 《Ecological Research》2002,17(2):195-206
Stable (13C and 15N) and radio- (14C, 137Cs and 210Pb) isotopes were determined for termites that
have been sampled from a dry evergreen forest in Thailand. A wood-feeding termite, Microcerotermes crassus, was separated from soil-feeders: Termes propinquus, Termes comis and Dicuspiditermes makhamensis by 13C and 15N values. The Termes group in Thailand had less diverse values in 13C and 15N than those in Australia, where the feeding habits of the Termes group are more diverse. Other soil-feeding termites produced similar 13C values, but a larger range in 15N values. 14C-percent modern carbon (pMC) values suggest that the soil-feeding termites used younger carbon than the wood-feeding termites, and this was consistent with the termites from Cameroon, central Africa. Values of 13C and 14C-pMC indicate that surface soil was used by a soil-feeding termite, D. makhamensis, in making the nest mounds, and deeper soil (10–30 cm) by a fungus-growing termite, Macrotermes carbonarius. 210Pb and 137Cs were scarcely incorporated into the termites, although 214Pb was recovered from the workers. The results suggest that stable- and radioisotopes are useful in the study of detritivorous animals, organic matter decomposition and ecosystem engineering.Takuya Abe - deceased. 相似文献
174.
Yamashita H Nanba Y Onishi M Kimoto M Hiemori M Tsuji H 《Bioscience, biotechnology, and biochemistry》2002,66(11):2487-2490
A 36-kDa allergen, Tri a Bd 36K, was purified from wheat albumin and characterized. The protein was similar to barley peroxidase BP-1 both in its amino acid sequence and peroxidase activity. The enzyme seemed to contain L-fucose and D-mannose and the glycan moiety reacted with IgE antibodies in a patient's serum. 相似文献
175.
In various fern species, a large amount of rbcL sequence variation has been reported, and it is possible that these species contain several reproductively isolated cryptic
species. In our previous study on Asplenium nidus L., it was suggested that the plants growing in Mt. Halimun National Park, West Java, Indonesia, consist of several cryptic
species based on the results of crossing experiments among rbcL sequence types. In this study, we examined allozyme polymorphisms of five rbcL sequence types found in West Java in order to test the hypothesis that the assemblages of A. nidus delimited based on the rbcL sequences are separate Mendelian populations and gene flow is disrupted by reproductive isolation from one another. The calculated
fixation indices suggested that the individuals in each rbcL type are randomly crossing at least in the investigated localities. Nevertheless, these rbcL-based assemblages were genetically differentiated in allozymes that are encoded in their nuclear genomes, and it is also
suggested that gene flow is disrupted even between sympatrically distributed pairs of rbcL sequence types. Therefore, our findings support the view that the five rbcL sequence types in West Java are potential cryptic species.
Electronic Publication 相似文献
176.
Taki K Kogai T Kanamoto Y Hershman JM Brent GA 《Molecular endocrinology (Baltimore, Md.)》2002,16(10):2266-2282
177.
Tanabe S Kobayashi Y Takahata Y Morimatsu F Shibata R Nishimura T 《Biochemical and biophysical research communications》2002,293(5):1348-1353
Bovine serum albumin (BSA) is the major beef allergen. Since IgE and T cell recognitions are central to the specific immune response to allergens, the identification and immunologic characterization of B and T cell epitopes of BSA represent important steps in the development of treatments for beef allergy. Prior to our experiments, we hypothesized that BSA-specific antibodies and T cells react primarily with sequential epitopes in which the amino acid sequences differ greatly between bovine and human albumin. To clarify this hypothesis, 16 peptides corresponding to such regions were synthesized as candidate epitopes. Among them, at least two regions, aa336-345 and aa451-459, were found to be B cell (IgE-binding) epitopes. In inhibition ELISA experiments, EYAV (aa338-341) and LILNR (aa453-457) bound to patient IgE antibodies and were found to be the cores of the IgE-binding epitopes. Three regions, DDSPDLPKLKPDPNTLC (aa107-123), PHACYTSVFDKLKHLVDEP (aa364-382), and LSLILNRLC (aa451-459), were found to induce T cell proliferation in more than half of the patients tested. Of interest was that these three regions were also recognized by B cells. Information concerning human B and T cells epitopes can contribute greatly to the elucidation of the etiology of beef allergy. 相似文献
178.
179.
Kentaro Nagamine Yoko Kuzuhara Tsugunori Notomi 《Biochemical and biophysical research communications》2002,290(4):1195-1198
Loop-mediated isothermal amplification (LAMP), in which a specific DNA sequence can be directly amplified under isothermal conditions, yields DNA in large quantities of more than 500 microg/ml. We have developed a method to isolate single-stranded DNA fragments from LAMP products that are stem-loop DNAs with several inverted repeats of the target DNA. This method requires the TspRI restriction enzyme, a primer hybridized to the 3' overhanging sequence at its cleavage site, and a DNA polymerase with strand displacement activity. The LAMP products are digested with TspRI and are then extended using the primer, producing the strand-specific DNA fragments. All processes, from LAMP reaction to primer extension, can be carried out at the same temperature. The use of strand-specific DNA would be conducive for detection by hybridization technique such as DNA microarrays. 相似文献
180.
BACE1 interacts with nicastrin 总被引:4,自引:0,他引:4
Hattori C Asai M Oma Y Kino Y Sasagawa N Saido TC Maruyama K Ishiura S 《Biochemical and biophysical research communications》2002,293(4):1228-1232
Beta-amyloid peptide (Abeta) is generated through the proteolytic cleavage of beta-amyloid precursor protein (APP) by beta- and gamma-secretases. The beta-secretase, BACE1, initiates Abeta formation followed by gamma-cleavage within the APP transmembrane domain. Although BACE1 localizes in the transGolgi network (TGN), its physiological substrates and modulators are not known. In addition, the relationship to other secretase(s) also remains unidentified. Here, we demonstrate that BACE1 binds to nicastrin, a component of gamma-secretase complexes, in vitro, and that nicastrin activates beta-secretase activity in COS-7 cells. 相似文献