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41.
42.
Takako Suzuki Shin-ichi Katsumata Hiroshi Matsuzaki Kazuharu Suzuki 《Bioscience, biotechnology, and biochemistry》2016,80(7):1433-1435
We investigated the effects of a short-term dietary zinc deficiency on bone metabolism. Zinc deficiency increased the mRNA expression of zinc uptake transporters such as Zip1, Zip13, and Zip14 in bone. However, zinc deficiency might not maintain zinc storage in bone, resulting in a decrease in bone formation through downregulation of the expression levels of osteoblastogenesis-related genes. 相似文献
43.
Gliclazide inhibits proliferation but stimulates differentiation of white and brown adipocytes 总被引:1,自引:0,他引:1
Nakano N Miyazawa N Sakurai T Kizaki T Kimoto K Takahashi K Ishida H Takahashi M Suzuki K Ohno H 《Journal of biochemistry》2007,142(5):639-645
Gliclazide, a second-generation sulfonylurea, has anti-oxidant properties as well as hypoglycemic activities. In the present study, we investigated whether gliclazide affected proliferation and/or differentiation of HW white and HB2 brown adipocyte cell lines. Gliclazide inhibited proliferation of HW and HB2 cells in the medium containing fetal calf serum or epidermal growth factor (EGF). Gliclazide inhibited phosphorylation of EGF receptor and of extracellular signal-regulated kinase (ERK) 1/2 stimulated by EGF. Gliclazide increased lipid accumulation and peroxisome proliferator-activated receptor gamma (PPARgamma) expression in the early stage of differentiation of adipocytes. A K(ATP) channel activator, diazoxide, did not inhibit the increase of lipid accumulation by gliclazide. Furthermore, gliclazide inhibited the DNA-binding activity of PPARgamma in mature adipocytes. On the other hand, glibenclamide, other sulfonylurea, did not show these effects. These results indicate gliclazide inhibits proliferation and stimulates differentiation of adipocytes via down-regulation of the EGFR signalling. Gliclazide may have preventive and therapeutic effects on obesity, as well as on type 2 diabetes. 相似文献
44.
Enoki N Kiyoshima T Sakai T Kobayashi I Takahashi K Terada Y Sakai H 《Journal of molecular histology》2007,38(4):321-332
This study investigated the age-dependent changes in the number of BrdU- and TUNEL-positive cells in murine gingival tissue
and submandibular gland, and compared the findings with those in other tissues and organs. The cell proliferative activity
was decreased after 20 weeks of age in epithelial cells of the gingiva, tongue, buccal mucosa and skin. A decreased cell proliferative
activity was also associated with aging in the liver and kidney parenchymal cells. Meanwhile, cell death showed peculiar changes
in gingival subepithelial tissue, and mucous and serous acini of the submandibular gland. An increase of TUNEL-positive cells
was demonstrated in gingival subepithelial tissue after 20-week-old of age. A significant increase of TUNEL-positive cells
was also found in the mucous acinar cells in the 20-week-old mice and in the serous acini after 20 weeks. The fluctuation
in the number of TUNEL-positive cells in the subepithelial tissue of the skin, and BrdU- and TUNEL-positive staining ratios
in the liver was smaller than that in other tissue and organs throughout life. This study may provide useful information for
better understanding the influence of aging on the functional alteration that occurs in the gingival tissue and submandibular
gland of the elderly. 相似文献
45.
Akihiro Hirata Yoko Miyamoto Akihisa Kaneko Hiroki Sakai Kyoko Yoshizaki Tokuma Yanai Takako Miyabe‐Nishiwaki Juri Suzuki 《Journal of medical primatology》2019,48(2):137-140
Primary neuroendocrine neoplasm of the liver is extremely rare in both humans and non‐human primates. The present report describes the clinical and pathological findings of an aged Japanese macaque (Macaca fuscata) with hepatic neuroendocrine carcinoma. To our knowledge, this is the first report of hepatic neuroendocrine neoplasm in macaques. 相似文献
46.
What can dry reservoir sediments in a semi-arid region in Brazil tell us about cladocera? 总被引:1,自引:1,他引:0
A study of dry sediments in a semi-arid reservoir in northeast Brazil was undertaken. Eleven quadrants were sampled along a transect in the reservoir. Sediments were collected and transferred to distilled water in the laboratory where they were subsequently filtered through a 50 m mesh filter. Ecloded cladocerans were identified. Several species hatched in the laboratory, and were compared with the cladoceran community collected before the reservoir had dried out. In previous years, only Moina minuta, Diaphanosoma spinulosumand Alonella hamulata were found in the lake, each on a different sampling date. In the laboratory, however, other species like Macrothrix sp., Leydigia ipojucae, Latonopsis australis and Ceriodaphnia cornuta f. rigaudi hatched. We observed that those quadrants, which were located in higher parts of the reservoir, and had been dry for 13 years, contained species that appeared only in these quadrants. Thus, the sediments show that independently of the species actively present in the water column, sediments store species in diapause stages: an observation that should not be overlooked, especially in biodiversity studies. 相似文献
47.
The effect of regucalcin, a regulatory protein in intracellular signaling pathway, on cell death was investigated by using the cloned rat hepatoma H4-II-E cells overexpressing regucalcin. The hepatoma cells (wild-type) and stable regucalcin (RC)/pCXN2 transfectants were cultured for 72 h in medium containing 10% fetal bovine serum (FBS) to obtain subconfluent monolayers. After culture for 72 h, cells were further cultured for 12-72 h in medium without FBS containing either vehicle or lipopolysaccharide (LPS; 0.1 or 1.0 microg/ml). The number of wild-type cells was significantly decreased by culture for 24 or 48 h in the presence of LPS (0.1 or 1.0 microg/ml). The effect of LPS (0.1 or 1.0 microg/ml) in decreasing the number of hepatoma cells was significantly prevented in transfectants overexpressing regucalcin. However, the culture with LPS (0.1 or 1.0 microg/ml) for 72 h caused a significant decrease in cell number of transfectants. Ca(2+)/calmodulin-dependent nitric oxide (NO) synthase activity was significantly decreased by culture with LPS (1.0 microg/ml) for 24-72 h of wild-type cells. This decrease was significantly prevented in transfectants. LPS (0.1 or 1.0 microg/ml)-induced decrease in the number of wild-type cells was significantly prevented by culture with caspase-3 inhibitor (10(-8) M). Moreover, the number of wild-type cells was significantly decreased by culture with PD 98059 (10(-6) M), dibucaine (10(-6) M), or staurosporine (10(-6) M), which is an inhibitor of various protein kinases. The effect of PD 98059 or dibucaine on the number of wild-type cells was not observed in transfectants, although the effect of staurosporine was seen in transfectants. Culture with Bay K 8644 (2.5 x 10(-6) M), an agonist of Ca(2+) entry in cells, caused a significant decrease in the number of wild-type cells. Such an effect was not seen in transfectants. The presence of LPS did not significantly decrease the number of wild-type cells in the presence of Bay K 8644. Agarose gel electrophoresis showed the presence of low-molecular-weight deoxyribonucleic acid (DNA) fragments of adherent wild-type cells cultured with Bay K 8644, and this DNA fragmentation was significantly prevented in transfectants. This study demonstrates that overexpression of regucalcin has a suppressive effect on cell death induced by LPS or various intracellular signaling-related factors. 相似文献
48.
Expression of a sweet cherry DREB1/CBF ortholog in Arabidopsis confers salt and freezing tolerance 总被引:11,自引:0,他引:11
Kitashiba H Ishizaka T Isuzugawa K Nishimura K Suzuki T 《Journal of plant physiology》2004,161(10):1171-1176
Dehydration responsive element binding protein 1 (DREB1)/C-repeat binding factor (CBF) induces the expression of many stress-inducible genes in Arabidopsis. We have previously reported the identification of three DREB1/ICBF homologs from sweet cherry (Prunus avium). To identify the function of these homologs, one of the genes, CIG-B, was transformed into Arabidopsis. In one of the transgenic plant lines, the DREB1/CBF target gene cor15a was induced in the absence of stress treatment. The cor15a-overexpressing transgenic plant exhibited mild growth retardation and had greater salt and freezing tolerance than did the wild-type and the transgenic lines in which cor15a was not induced. These results suggest that this sweet cherry DREB1/CBF homolog has a function similar to that of DREB1/CBF. 相似文献
49.
50.
Activities of the matrix metalloproteinase stromelysin-2 (MMP-10) in matrix degradation and keratinocyte organization in wounded skin 下载免费PDF全文
Krampert M Bloch W Sasaki T Bugnon P Rülicke T Wolf E Aumailley M Parks WC Werner S 《Molecular biology of the cell》2004,15(12):5242-5254
The matrix metalloproteinase stromelysin-2 is expressed in keratinocytes of the epithelial tongue of skin wounds, suggesting a role in keratinocyte migration. Here, we show that stromelysin-2 enhances migration of cultured keratinocytes. To gain insight into the in vivo activities of stromelysin-2 in epithelial repair, we generated transgenic mice expressing a constitutively active stromelysin-2 mutant in keratinocytes. These animals had no alterations in skin architecture, and the healing rate of skin wounds was normal. Histologically, however, we found abnormalities in the organization of the wound epithelium. Keratinocytes at the migrating epidermal tip were scattered in most sections of mice with high expression level, and there was a reduced deposition of new matrix. In particular, the staining pattern of laminin-5 at the wound site was altered. This may be due to proteolytic processing of laminin-5 by stromelysin-2, because degradation of laminin-5 by this enzyme was observed in vitro. The inappropriate matrix contact of keratinocytes was accompanied by aberrant localization of beta1-integrins and phosphorylated focal adhesion kinase, as well as by increased apoptosis of wound keratinocytes. These results suggest that a tightly regulated expression level of stromelysin-2 is required for limited matrix degradation at the wound site, thereby controlling keratinocyte migration. 相似文献