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1.
Masayo Suzuki Hiroyuki Ishida Yukimasa Shiotsu Taisuke Nakata Shiro Akinaga Shigemitsu Takashima Toshiaki Utsumi Toshiaki Saeki Nobuhiro Harada 《The Journal of steroid biochemistry and molecular biology》2009,113(3-5):195-201
In order to evaluate the importance of estrogen production in tumor and surrounding tissues, we measured mRNA expression levels of 5 enzymes participating to estrogen synthesis in situ and 4 breast cancer-related proteins in 27 pairs of tumor and non-malignant tissues. Steroid sulfatase (STS) mRNA was more frequently detected in tumor tissues rather than in their non-malignant counterparts. Estrogen sulfotransferase (EST) was constantly expressed with high level not only in tumor tissues but also in their surrounding non-malignant counterparts. In contrast, mRNA expression levels of aromatase, and 17β-hydroxysteroid dehydrogenase type I and II were relatively low and detected only in small proportion of the patients. We also measured the mRNA expression levels of the same nine genes in tumor tissues of 197 breast cancer patients, and analyzed relationship between the mRNA expression level and the clinicopathological parameters. The mRNA expression levels of STS, aromatase and erbB2 in tumor tissues increased as breast cancer progressed. The tumoral mRNA expression levels of STS, estrogen receptor β, and erbB2 in patients with recurrence were higher than those in patients without recurrence. Upregulation of STS expression plays an important role in tumor progression of human breast cancer and is considered to be responsible for estrogen production in tumor and surrounding tissues. 相似文献
2.
Yusuke Nakamura Michio Ogawa Takahiro Nishide Mitsuru Emi Goro Kosaki Seiichi Himeno Kenichi Matsubara 《Gene》1984,28(2):263-270
The nucleotide sequences of the cloned human salivary and pancreatic α-amylase cDNAs correspond to the continuous mRNA sequences of 1768 and 1566 nucleotides, respectively. These include all of the amino acid coding regions. Salivary cDNA contains 200 bp in the 5′-noncoding region and 32 in the 3′-noncoding region. Pancreatic cDNA contains 3 and 27 bp of 5′- and 3′-noncoding regions, respectively. The nucleotide sequence humology of the two cDNAs is 96% in the coding region, and the predicted amino acid sequences are 94% homologous.Comparison of the sequences of human α-amylase cDNAs with those previously obtained for mouse α-amylase genes (Hagenbuchle et al., 1980; Schibler et al., 1982) showed the possibility of gene conversion between the two genes of human α-amylase. 相似文献
3.
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
4.
Host discrimination modulates brood guarding behaviour and the adaptive superparasitism in the parasitoid wasp Trissolcus semistriatus (Hymenoptera: Scelionidae) 下载免费PDF全文
Because hosts utilized by parasitoids are vulnerable to further oviposition by conspecifics, host guarding benefits female wasps. The present study aims to test whether female adults regulate brood guarding behaviour by host discrimination in a solitary parasitoid Trissolcus semistriatus by presenting an intact or parasitized host egg mass to a female adult. Virgin females without oviposition experience have host discrimination ability, which enables them to adjust the number of eggs laid in the hosts. Mating experience increases superparasitism by female adults, whereas mated females achieve a higher discrimination ability as a result of oviposition experience and show a lower superparasitism rate. As expected, females exhibit brood guard after parasitizing an intact host egg mass, whereas those females visiting a previously parasitized host egg mass, do not. Because the survival of eggs in superparasitized hosts is relatively low, regulating brood guarding behaviour by host discrimination is adaptive for female wasps. 相似文献
5.
Raymond L. White Jean-Marc Lalouel G. Mark Lathrop Mark F. Leppert Yusuke Nakamura Peter O'Connell 《The Western journal of medicine》1987,147(4):423-427
Although a number of human genes that cause disease have been traced through the defective product, most genetic defects are recognized only by phenotype. When the biochemical defect is unknown, a gene can be located only through molecular approaches based on coinheritance (genetic linkage) of the disease phenotype with a particular allele of a polymorphic DNA marker that has already been mapped to a specific chromosomal region. Linkage studies in affected families have already localized genes for several important diseases, including cystic fibrosis. Finding a genetic linkage in families in which a disease segregates requires that the human genetic map have a large number of polymorphic markers; when the map is dense enough, any disease gene can be located by linkage to a known marker. Many DNA segments with a high degree of polymorphism are being found and mapped as markers in normal reference pedigrees. Genetic linkage mapping has implications even broader than its application to prenatal diagnosis or therapeutic strategy; analyzing mutations in important genes will illuminate basic mechanisms in molecular biology and the early events that lead to cancer and other disorders. 相似文献
6.
Yoshiki Takashima Hiroki Nakajima Kenji Sonomoto Atsuo Tanaka 《Applied microbiology and biotechnology》1987,27(2):106-109
Summary
Streptomyces peucetius cells were immobilized by entrapment in calcium alginate and a photosensitive synthetic polymer, and used for the production of daunorubicin (daunomycin), which is known to be an antitumour reagent. The use of cultivation media removed insoluble components in a natural medium prevented rapid decrease in daunorubicin titer after maximum production. These entrapped cells could be used at least five times for repeated daunorubicin production; the total cultivation period was 45 days. 相似文献
7.
8.
Hiroaki Nobuhara Keisuke Kuida Makoto Furutani Toshihiko Shiroishi Kazuo Moriwaki Yusuke Yanagi Tomio Tada 《Immunogenetics》1989,30(6):405-413
Southern blots of genomic DNA from 23 strains of laboratory mice and 19 individual wild mice were examined for restriction
fragment length polymorphisms in their loci encoding the T-cell receptors (Tcr): the constant regions of the α, β, and γ chains
(C
α,C
β, andC
γ) and a variable region family of the β chain (V
β8). Only a few polymorphisms were observed for each locus in the laboratory mice after using three restriction enzymes,Bam HI,Eco RI, andHind III. All the laboratory mice examined fall into one of two types for theC
α,C
β andV
β8 loci and one of three types for theC
γ. These types are found in some of the wild mice studied, indicating that they were already present in the founder mice of
laboratory mouse strains. In contrast, theTcr genes are highly polymorphic among wild mice. Analysis of the polymorphisms in these loci suggests that laboratory mice have
inherited their genes not only fromMus musculus domesticus, but also from other subspecies, and much more than previously believed from Asian subspecies. 相似文献
9.
10.
Summary An attempt at cytochemical demonstration of acidification proton-translocating ATPase (H+-ATPase) of Golgi complex in rat pancreatic acinar cells has been made by using p-nitrophenylphosphatase (NPPase) cytochemistry
which is used for detecting of Na+-K+-ATPase (Mayahara et al. 1980) and gastric H+-K+-ATPase (Fujimoto et al. 1986). K+-independent NPPase activity was observed on the membrane of the trans cisternae of Golgi complex, but not inside of cisternae. The localization of NPPase activity is different from that of acid
phosphatase activity where reaction products were seen on the inside of the trans Golgi cisternae. Since this activity was insensitive to vanadate, ouabain and independent of potassium ions, it was distinct
from plasma membranous ATPases such as Na+-K+-ATPase and Ca2+-ATPase. The K+-independent NPPase activity was diminished by the inhibitors of H+-ATPase such as N-ethylmaleimide (NEM) and 4,4′-diisothiocyanostilbene-2,2′-disulfonic acid (DIDS). The NPPase reaction products
were also seen on the membranes of other acidic organelles, i.e., lysosomes, endosomes, autophagosomes and coated vesicles.
These results suggest that NPPase activity on the membrane of the Golgi complex and other acidic organelles corresponds with
H+-ATPase which plays a role in acidification. 相似文献