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21.
Masashi Kato Mayuko Y. Kumasaka Shoko Ohnuma Akio Furuta Yoko Kato Hossain U. Shekhar Michiyo Kojima Yasuko Koike Nguyen Dinh Thang Nobutaka Ohgami Thuy Bich Ly Xiaofang Jia Husna Yetti Hisao Naito Gaku Ichihara Ichiro Yajima 《PloS one》2013,8(6)
Health risk for well drinking water is a worldwide problem. Our recent studies showed increased toxicity by exposure to barium alone (≤700 µg/L) and coexposure to barium (137 µg/L) and arsenic (225 µg/L). The present edition of WHO health-based guidelines for drinking water revised in 2011 has maintained the values of arsenic (10 µg/L) and barium (700 µg/L), but not elements such as manganese, iron and zinc. Nevertheless, there have been very few studies on barium in drinking water and human samples. This study showed significant correlations between levels of arsenic and barium, but not its homologous elements (magnesium, calcium and strontium), in urine, toenail and hair samples obtained from residents of Jessore, Bangladesh. Significant correlation between levels of arsenic and barium in well drinking water and levels in human urine, toenail and hair samples were also observed. Based on these results, a high-performance and low-cost adsorbent composed of a hydrotalcite-like compound for barium and arsenic was developed. The adsorbent reduced levels of barium and arsenic from well water in Bangladesh and Vietnam to <7 µg/L within 1 min. Thus, we have showed levels of arsenic and barium in humans and propose a novel remediation system. 相似文献
22.
Driven by the same Ig enhancer and SV40 T promoter ras induced lung adenomatous tumors, myc induced pre-B cell lymphomas and SV40 large T gene a variety of tumors in transgenic mice. 总被引:17,自引:7,他引:17 下载免费PDF全文
Y Suda S Aizawa S Hirai T Inoue Y Furuta M Suzuki S Hirohashi Y Ikawa 《The EMBO journal》1987,6(13):4055-4065
23.
Yoshina S Sakaki K Yonezumi-Hayashi A Gengyo-Ando K Inoue H Iino Y Mitani S 《Molecular biology of the cell》2012,23(9):1728-1741
A disintegrin-like and metalloprotease with thrombospondin type I motif (ADAMTS9) is a member of the secreted metalloprotease family that is believed to digest extracellular matrix (ECM) proteins outside of cells. Its Caenorhabditis elegans orthologue, GON-1, is involved in ECM degradation and is required for gonad morphogenesis. ADAMTS9 and GON-1 have similar domain structures, and both have a unique C-terminal domain called the "GON domain," whose function remains unknown. Here we show that down-regulation of human ADAMTS9 and C. elegans GON-1 results in the inhibition of protein transport from the endoplasmic reticulum (ER) to the Golgi. This phenotype was rescued by the expression of the GON domain localizing in the ER in human cells and C. elegans. We propose a novel function of ADAMTS9 and GON-1 in the ER that promotes protein transport from the ER to the Golgi. This function is GON-domain dependent but protease activity independent. 相似文献
24.
Characterization of p-chloroamphetamine-induced penile erection and ejaculation in anesthetized rats
Yonezawa A Watanabe C Ando R Furuta S Sakurada S Yoshimura H Iwanaga T Kimura Y 《Life sciences》2000,67(25):3031-3039
Methodological shortcomings present in elicitation of male sexual reflexes in anesthetized animals. The present study has demonstrated, however, that intraperitoneal (i.p.) injection of p-chloroamphetamine (PCA), an indirect serotonin (5-HT) agonist, elicited simultaneously both penile erection and ejaculation in anesthetized rats. PCA (2.5-10.0 mg/kg, i.p.) caused an intermittent cluster of genital responses consisting of penile erection, glans erections, and penile cups, which closely resembles the response observed during the ex copula tests in unanesthetized rats. Measurements of intracavernous penile pressure showed that rhythmic changes in penile pressure were produced by PCA, together with glans erections and penile cups. PCA also caused a frequent ejaculations and the weighing of ejaculate accumulated over 0.5 hr was increased in a bell-shaped pattern, and the maximum effect was observed at 5.0 mg/kg. Pretreatment with p-chlorophenylalanine, a serotonin (5-HT)-synthesis inhibitor, significantly inhibited the expression of PCA-induced penile erection and ejaculation, while acute spinal transection at thoracic level did not affect the sexual responses. These results indicate that PCA-induced penile erection and ejaculation in anesthetized rats are mainly produced by the release of 5-HT, which is limited to the lower spinal cord and/or the peripheral sites. Furthermore, the sexual responses can be easily and reliably elicited by administration of PCA, which may be useful for the study of the mechanisms underlying male sexual functions. 相似文献
25.
Hashimoto K Morishige K Sawada K Tahara M Shimizu S Ogata S Sakata M Tasaka K Kimura T 《Biochemical and biophysical research communications》2007,354(2):478-484
We previously reported that alendronate inhibits intraperitoneal dissemination in an in vivo ovarian cancer model. Recently, nitrogen-containing bisphosphonates have been reported to have antiangiogenic activities. In this study, alendronate inhibited human umbilical vein endothelial cell (HUVEC) migration and capillary-like structure formation in vitro. These inhibitory effects were associated with reduced Rho activation and suppression of the formation of actin stress fibers and focal adhesions in HUVECs. Furthermore, the inhibition by alendronate was reversed by geranylgeraniol, which abrogated the inhibition of Rho geranylgeranylation. Next, we examined the effect of alendronate on angiogenesis in disseminated ovarian tumors of athymic immunodeficient mice. Alendronate treatment reduced the intra-tumor neoangiogenesis compared with that in the non-treated mice, although tumor-derived VEGF expression was not altered. In conclusion, the in vivo anti-tumor effect of alendronate might be derived, at least in part, from its direct antiangiogenic effects on intra-tumor endothelial cells by inhibiting Rho geranylgeranylation. 相似文献
26.
Chi L Saarela U Railo A Prunskaite-Hyyryläinen R Skovorodkin I Anthony S Katsu K Liu Y Shan J Salgueiro AM Belo JA Davies J Yokouchi Y Vainio SJ 《PloS one》2011,6(11):e27676
The epithelial ureteric bud is critical for mammalian kidney development as it generates the ureter and the collecting duct system that induces nephrogenesis in dicrete locations in the kidney mesenchyme during its emergence. We show that a secreted Bmp antagonist Cerberus homologue (Cer1) fine tunes the organization of the ureteric tree during organogenesis in the mouse embryo. Both enhanced ureteric expression of Cer1 and Cer1 knock out enlarge kidney size, and these changes are associated with an altered three-dimensional structure of the ureteric tree as revealed by optical projection tomography. Enhanced Cer1 expression changes the ureteric bud branching programme so that more trifid and lateral branches rather than bifid ones develop, as seen in time-lapse organ culture. These changes may be the reasons for the modified spatial arrangement of the ureteric tree in the kidneys of Cer1+ embryos. Cer1 gain of function is associated with moderately elevated expression of Gdnf and Wnt11, which is also induced in the case of Cer1 deficiency, where Bmp4 expression is reduced, indicating the dependence of Bmp expression on Cer1. Cer1 binds at least Bmp2/4 and antagonizes Bmp signalling in cell culture. In line with this, supplementation of Bmp4 restored the ureteric bud tip number, which was reduced by Cer1+ to bring it closer to the normal, consistent with models suggesting that Bmp signalling inhibits ureteric bud development. Genetic reduction of Wnt11 inhibited the Cer1-stimulated kidney development, but Cer1 did not influence Wnt11 signalling in cell culture, although it did inhibit the Wnt3a-induced canonical Top Flash reporter to some extent. We conclude that Cer1 fine tunes the spatial organization of the ureteric tree by coordinating the activities of the growth-promoting ureteric bud signals Gndf and Wnt11 via Bmp-mediated antagonism and to some degree via the canonical Wnt signalling involved in branching. 相似文献
27.
Kiyoshi Furuta Edward K. L. Chan Kendo Kiyosawa Georg Reimer Christoph Luderschmidt Eng M. Tan 《Chromosoma》1997,106(1):11-19
Some autoimmune sera containing anticentromere autoantibodies also recognize a doublet of Mr 23 000 (p23) and 25 000 (p25)
in addition to CENP (centromere protein)-A (Mr 19 000), -B (Mr 80 000), and -C (Mr 140 000). A p25 antigen (HP1Hsα) has been shown to be a human homolog of Drosophila HP1 (heterochromatin protein 1). We have isolated a cDNA clone encoding another form of p25 (HP1Hsβor p25β) from a λZap HepG2 library using human autoimmune serum. The deduced amino acid sequence of the clone contained a
conserved chromodomain (chromatin modifier domain) in the N-terminal region and a heterochromatin binding domain in the C-terminal region. In immunofluorescence experiments,
only affinity purified antibodies reactive with the C-terminal (amino acids 70–185) domain showed nucleoplasmic and heterochromatin
staining, whereas N-terminal (amino acids 1–115) specific antibodies were nonreactive. In metaphase chromosome spreads, the
C-terminal domain antibody was also localized to the centromeric regions of chromosomes. Association with centromeres was
most prominent at anaphase and changed to a more generalized association with whole chromosomes in telophase. The cooccurrence
of autoantibodies to centromere proteins and HP1 in certain autoimmune diseases might be a reflection of coordinated immune
responses to these closely associated sets of proteins.
Received: 8 August 1996; in revised form: 4 December 1996 / Accepted: 17 December 1996 相似文献
28.
29.
Norihide Hinomoto Masahiko Muraji Takashi Noda Toru Shimizu Kenjiro Kawasaki 《Biological Control》2004,31(3):642
We developed multiplex polymerase chain reaction methods to identify five Orius (Heteroptera: Anthocoridae) species that occur commonly in Japan: Orius sauteri, Orius minutus, Orius strigicollis, Orius nagaii, and Orius tantillus. The method amplified internal transcribed spacer 1 of the nuclear ribosomal DNA by using five primers simultaneously and produced species-specific banding patterns upon agarose gel electrophoresis. Reliability of the method was tested for 350 individuals of 23 strains, and consistent results were obtained. Dichotomous keys are also provided for easy and quick species identification. 相似文献
30.
Bandow K Nishikawa Y Ohnishi T Kakimoto K Soejima K Iwabuchi S Kuroe K Matsuguchi T 《Journal of cellular physiology》2007,211(2):392-398
Constant mechanical stress is essential for the maintenance of bone mass and strength, which is achieved through the cooperative functions of osteoblasts and osteoclasts. However, it has not been fully elucidated how these cell types mediate mechanical signals. Low-intensity pulsed ultrasound (LIPUS) therapy is a recently developed method for application of mechanical stress, and is used clinically to promote bone fracture healing. In the present study, we applied LIPUS to osteoblasts at different stages of maturation and analyzed their chemokine and cytokine expression. In comparison with their immature counterparts, mature osteoblasts expressed significantly higher levels of mRNAs for the receptor activator of nuclear factor kappa B ligand (RANKL), monocyte chemoattractant protein (MCP)-1, and macrophage-inflammatory protein (MIP)-1beta after a few hours of LIPUS treatment. Intriguingly, protein and mRNA expression of angiotensin II type 1 receptor (AT1), a known mechanoreceptor in cardiomyocytes, was detected in osteoblasts, and the level of expression increased significantly during cell maturation. Furthermore, LIPUS-induced extracellular signal-regulated kinase (ERK) phosphorylation and RANKL/chemokine expression was abrogated by a specific AT1 inhibitor. Thus, AT1 may play one of the essential roles in bone metabolism as a mechanoreceptor of osteoblasts. 相似文献