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951.
Expression of four BMP antagonist genes, noggin, chordin, gremlin and Follistatin, was examined during chick feather development. Although expression of noggin and chordin was not detected, gremlin and Follistatin were expressed differentially in feather buds. The differential expression patterns of gremlin and Follistatin change dynamically from the nascent inter-feather bud region to the posterior domain of the feather bud. 相似文献
952.
Kohji Seio Ryuya Tawarada Takeshi Sasami Masashi Serizawa Misako Ise Akihiro Ohkubo Mitsuo Sekine 《Bioorganic & medicinal chemistry》2009,17(20):7275-7280
2′-O-Carbamoyluridine (Ucm) was synthesized and incorporated into DNAs and 2′-O-Me-RNAs. The oligonucleotides incorporating Ucm formed less stable duplexes with their complementary and Ucm–U, Ucm–C single-base mismatched DNAs and RNAs in comparison with those without the carbamoyl group. On the contrary, the Tm analyses revealed that the duplexes with a mismatched Ucm–G base pair showed almost the same thermostability as the corresponding unmodified duplexes. Molecular dynamics (MD) simulations of the Ucm-modified 2′-O-Me-RNA/RNA duplexes with Ucm–G mismatched base pair suggested that the carbamoyl group could participate in the Ucm–G base pair by an additional intermolecular hydrogen bond between the carbamoyl oxygen and the H2 of the guanine base. 相似文献
953.
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956.
Hiroaki Takayama Hirofumi Misu Hisakazu Iwama Keita Chikamoto Yoshiro Saito Koji Murao Atsushi Teraguchi Fei Lan Akihiro Kikuchi Reina Saito Natsumi Tajima Takayoshi Shirasaki Seiichi Matsugo Ken-ichi Miyamoto Shuichi Kaneko Toshinari Takamura 《The Journal of biological chemistry》2014,289(1):335-345
957.
Ryoko Kikuchi Yoshihiro Kikuchi Hitoshi Tsuda Hitoshi Maekawa Ken-ichi Kozaki Issei Imoto Seiichi Tamai Akihiro Shiotani Keiichi Iwaya Masaru Sakamoto Takao Sekiya Osamu Matsubara 《Human cell》2014,27(3):121-128
Connective tissue growth factor (CTGF) has been reported to play critical roles in the tumorigenesis of several human malignancies. This study was performed to evaluate CTGF protein expression in head and neck squamous cell carcinoma (HNSCC). Surgical specimens from 76 primary HNSCC were obtained with written informed consents and the expression level of CTGF was immunohistochemically evaluated. The cytoplasmic immunoreactivity of CTGF in cancer cells was semiquantitatively classified into low and high expression. Among all 76 cases with or without neoadjuvant therapy, low CTGF showed significantly longer (P = 0.0282) overall survival (OS), but not disease-free survival (DFS) than high CTGF. Although low CTGF in patients with stage I, II and III did not result in any significant difference of the OS and DFS, stage IV HNSCC patients with low CTGF showed significantly longer OS (P = 0.032) and DFS (P = 0.0107) than those with high CTGF. These differences in stage IV cases were also confirmed using multivariate analyses. These results suggest that low CTGF in stage IV HNSCC is an independent prognostic factor, despite with or without neoadjuvant therapy. 相似文献
958.
Naotoshi Sugimoto Tomoko Toma Masaki Shimizu Mondo Kuroda Taizo Wada Akihiro Yachie 《Cell biology and toxicology》2014,30(5):289-299
The blood–brain barrier (BBB) selectively controls the homeostasis of the central nervous system (CNS) environment using specific structural and biochemical features of the endothelial cells, pericytes, and glial limitans. Glial cells, which represent the cellular components of the mature BBB, are the most numerous cells in the brain and are indispensable for neuronal functioning. We investigated the effects of Shiga toxin on glial cells in vitro. Shiga toxin failed to inhibit cell proliferation but attenuated expression of heat shock protein 70, which is one of the chaperone proteins, in cultured and primary glial cells. Furthermore, the combination of Shiga toxin and a heat shock procedure induced cell apoptosis and decreased cell proliferation in both cells. Thus, we speculate that glial cell death in response to the combination of Shiga toxin and heat shock might weaken the BBB and induce central nervous system complications. 相似文献
959.
Naoko Kubo Birukawa Kazuyuki Murase Yasushi Sato Akemi Kosaka Akihiro Yoneda Hiroki Nishita Ryosuke Fujita Miyuki Nishimura Takafumi Ninomiya Keiko Kajiwara Miyono Miyazaki Yusuke Nakashima Sigenori Ota Yuya Murakami Yasunobu Tanaka Kenjiro Minomi Yasuaki Tamura Yoshiro Niitsu 《The Journal of biological chemistry》2014,289(29):20209-20221
Stellate cells are distributed throughout organs, where, upon chronic damage, they become activated and proliferate to secrete collagen, which results in organ fibrosis. An intriguing property of hepatic stellate cells (HSCs) is that they undergo apoptosis when collagen is resolved by stopping tissue damage or by treatment, even though the mechanisms are unknown. Here we disclose the fact that HSCs, normal diploid cells, acquired dependence on collagen for their growth during the transition from quiescent to active states. The intramolecular RGD motifs of collagen were exposed by cleavage with their own membrane type 1 matrix metalloproteinase (MT1-MMP). The following evidence supports this conclusion. When rat activated HSCs (aHSCs) were transduced with siRNA against the collagen-specific chaperone gp46 to inhibit collagen secretion, the cells underwent autophagy followed by apoptosis. Concomitantly, the growth of aHSCs was suppressed, whereas that of quiescent HSCs was not. These in vitro results are compatible with the in vivo observation that apoptosis of aHSCs was induced in cirrhotic livers of rats treated with siRNAgp46. siRNA against MT1-MMP and addition of tissue inhibitor of metalloproteinase 2 (TIMP-2), which mainly inhibits MT1-MMP, also significantly suppressed the growth of aHSCs in vitro. The RGD inhibitors echistatin and GRGDS peptide and siRNA against the RGD receptor αVβ1 resulted in the inhibition of aHSCs growth. Transduction of siRNAs against gp46, αVβ1, and MT1-MMP to aHSCs inhibited the survival signal of PI3K/AKT/IκB. These results could provide novel antifibrosis strategies. 相似文献
960.
Jan Mueller Julia Pfanzelter Christoph Winkler Akihiro Narita Christophe Le Clainche Maria Nemethova Marie-France Carlier Yuichiro Maeda Matthew D. Welch Taro Ohkawa Christian Schmeiser Guenter P. Resch J. Victor Small 《PLoS biology》2014,12(1)
Several pathogens induce propulsive actin comet tails in cells they invade to disseminate their infection. They achieve this by recruiting factors for actin nucleation, the Arp2/3 complex, and polymerization regulators from the host cytoplasm. Owing to limited information on the structural organization of actin comets and in particular the spatial arrangement of filaments engaged in propulsion, the underlying mechanism of pathogen movement is currently speculative and controversial. Using electron tomography we have resolved the three-dimensional architecture of actin comet tails propelling baculovirus, the smallest pathogen yet known to hijack the actin motile machinery. Comet tail geometry was also mimicked in mixtures of virus capsids with purified actin and a minimal inventory of actin regulators. We demonstrate that propulsion is based on the assembly of a fishbone-like array of actin filaments organized in subsets linked by branch junctions, with an average of four filaments pushing the virus at any one time. Using an energy-minimizing function we have simulated the structure of actin comet tails as well as the tracks adopted by baculovirus in infected cells in vivo. The results from the simulations rule out gel squeezing models of propulsion and support those in which actin filaments are continuously tethered during branch nucleation and polymerization. Since Listeria monocytogenes, Shigella flexneri, and Vaccinia virus among other pathogens use the same common toolbox of components as baculovirus to move, we suggest they share the same principles of actin organization and mode of propulsion. 相似文献