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971.
972.
Ryuta Terada Mahiko Abe Takuzo Abe Masakazu Aoki Akihiro Dazai Hikaru Endo Mitsunobu Kamiya Hiroshi Kawai Akira Kurashima Taizo Motomura Noboru Murase Yoshihiko Sakanishi Hiromori Shimabukuro Jiro Tanaka Goro Yoshida Misuzu Aoki 《Phycological Research》2021,69(1):12-30
“Monitoring Sites 1000” – Japan's long‐term monitoring survey was established in 2003, based on the Japanese Government policy for the conservation of biodiversity. Ecological surveys have been conducted on various types of ecosystems at approximately 1000 sites in Japan for 15 years now and are planned to be carried out for 100 years. Since 2008, seaweed communities had been monitored at six sites, featuring the kelp (e.g. Saccharina and Ecklonia; Laminariales) and Sargassum (Fucales) communities in the subarctic and temperate regions of Japan. Annual surveys were carried out during the season when these canopy‐forming seaweeds are most abundant. A non‐destructive quadrat sampling method, with permanent quadrats placed along transects perpendicular to the shoreline, was used to determine species composition, coverage, and vertical distribution of seaweeds at these sites; while destructive sampling was done every 5 years to determine biomass. The occurrence of canopy‐forming species Saccharina japonica (var. japonica) and Ecklonia cava have appeared to be stable at the Muroran (southwestern part of Hokkaido Island) and Shimoda (Pacific coast of middle Honshu Island) sites, respectively; whereas the coverage of Ecklonia radicosa (= Eckloniopsis radicosa) at the Satsuma‐Nagashima site in southern part of Kyushu Island was highly variable until its sudden disappearance from the habitat in 2016. Thalli of E. radicosa lost most of their blades through browsing by herbivorous fish, and thus, this may be one of the causes of the decline. A shift in the community structure related to environmental changes had also been observed at some other sites. Pre‐ and post‐disaster data revealed the impact of the 2011 earthquake and tsunami disasters, including a shift in the vertical distribution of Ecklonia bicyclis (= Eisenia bicyclis) to shallower depths at the Shizugawa site in the Pacific coast of northern Honshu Island, due to seafloor subsidence. 相似文献
973.
Masahiro Nishikawa Akihiro Inoue Takanori Ohnishi Hajime Yano Saya Ozaki Yonehiro Kanemura Satoshi Suehiro Yoshihiro Ohtsuka Shohei Kohno Shiro Ohue Seiji Shigekawa Hideaki Watanabe Riko Kitazawa Junya Tanaka Takeharu Kunieda 《Translational oncology》2021,14(8)
The poor prognosis of glioblastoma multiforme (GBM) is primarily due to highly invasive glioma stem-like cells (GSCs) in tumors. Upon GBM recurrence, GSCs with highly invasive and highly migratory activities must assume a less-motile state and proliferate to regenerate tumor mass. Elucidating the molecular mechanism underlying this transition from a highly invasive phenotype to a less-invasive, proliferative tumor could facilitate the identification of effective molecular targets for treating GBM. Here, we demonstrate that severe hypoxia (1% O2) upregulates CD44 expression via activation of hypoxia-inducible factor (HIF-1α), inducing GSCs to assume a highly invasive tumor. In contrast, moderate hypoxia (5% O2) upregulates osteopontin expression via activation of HIF-2α. The upregulated osteopontin inhibits CD44-promoted GSC migration and invasion and stimulates GSC proliferation, inducing GSCs to assume a less-invasive, highly proliferative tumor. These data indicate that the GSC phenotype is determined by interaction between CD44 and osteopontin. The expression of both CD44 and osteopontin is regulated by differential hypoxia levels. We found that CD44 knockdown significantly inhibited GSC migration and invasion both in vitro and in vivo. Mouse brain tumors generated from CD44-knockdown GSCs exhibited diminished invasiveness, and the mice survived significantly longer than control mice. In contrast, siRNA-mediated silencing of the osteopontin gene decreased GSC proliferation. These results suggest that interaction between CD44 and osteopontin plays a key role in tumor progression in GBM; inhibition of both CD44 and osteopontin may represent an effective therapeutic approach for suppressing tumor progression, thus resulting in a better prognosis for patients with GBM. 相似文献
974.
Tatsuki Soyama Akira Sakuragi Daisuke Oishi Yuka Kimura Hiromasa Aoki Akihiro Nomoto Shigenobu Yano Hirotada Nishie Hiromi Kataoka Mineyoshi Aoyama 《Translational oncology》2021,14(2)
M2-like tumor-associated macrophages (M2-TAMs) in cancer tissues are intimately involved in cancer immunosuppression in addition to growth, invasion, angiogenesis, and metastasis. Hence, considerable attention has been focused on cancer immunotherapies targeting M2-TAMs. However, systemic therapies inhibit TAMs as well as other macrophages important for normal immune responses throughout the body. To stimulate tumor immunity with fewer side effects, we targeted M2-TAMs using photodynamic therapy (PDT), which damages cells via a nontoxic photosensitizer with harmless laser irradiation. We synthesized a light-sensitive compound, mannose-conjugated chlorin e6 (M-chlorin e6), which targets mannose receptors highly expressed on M2-TAMs. M-chlorin e6 accumulated more in tumor tissue than normal skin tissue of syngeneic model mice and was more rapidly excreted than the second-generation photosensitizer talaporfin sodium. Furthermore, M-chlorin e6 PDT significantly reduced the volume and weight of tumor tissue. Flow cytometric analysis revealed that M-chlorin e6 PDT decreased the proportion of M2-TAMs and increased that of anti-tumor macrophages, M1-like TAMs. M-chlorin e6 PDT also directly damaged and killed cancer cells in vitro. Our data indicate that M-chlorin e6 is a promising new therapeutic agent for cancer PDT. 相似文献
975.
Norio?OnikuraEmail author Jun?Nakajima Ryutei?Inui Hiroshi?Mizutani Midori?Kobayakawa Shinji?Fukuda Takahiko?Mukai 《Ichthyological Research》2011,58(4):382-387
The potential invasiveness of 28 freshwater fishes in northern Kyushu Island, Japan, was evaluated using the Fish Invasiveness
Scoring Kit (FISK). The five co-authors scored the level of invasiveness for each species and calculated the total FISK scores;
the maximum and minimum scores were then eliminated, and the mean of the remaining three scores was used as the final score
for each species. The mean scores ranged from 11.0 (Hypomesus nipponensis) to 31.0 (Cyprinus carpio). The receiver operating characteristic curve indicated that the threshold value between fishes that present a high risk
of invasion and the other species were 19.8. 相似文献
976.
Fukudome A Kanaya A Egami M Nakazawa Y Hiraguri A Moriyama H Fukuhara T 《RNA (New York, N.Y.)》2011,17(4):750-760
Arabidopsis thaliana Dicer-like 4 (DCL4) produces 21-nt small interfering RNAs from both endogenous and exogenous double-stranded RNAs (dsRNAs), and it interacts with DRB4, a dsRNA-binding protein, in vivo and in vitro. However, the role of DRB4 in DCL4 activity remains unclear because the dsRNA-cleaving activity of DCL4 has not been characterized biochemically. In this study, we biochemically characterize DCL4's Dicer activity and establish that DRB4 is required for this activity in vitro. Crude extracts from Arabidopsis seedlings cleave long dsRNAs into 21-nt small RNAs in a DCL4/DRB4-dependent manner. Immunoaffinity-purified DCL4 complexes produce 21-nt small RNAs from long dsRNA, and these complexes have biochemical properties similar to those of known Dicer family proteins. The DCL4 complexes purified from drb4-1 do not cleave dsRNA, and the addition of recombinant DRB4 to drb4-1 complexes specifically recovers the 21-nt small RNA generation. These results reveal that DCL4 requires DRB4 to cleave long dsRNA into 21-nt small RNAs in vitro. Amino acid substitutions in conserved dsRNA-binding domains (dsRBDs) of DRB4 impair three activities: binding to dsRNA, interacting with DCL4, and facilitating DCL4 activity. These observations indicate that the dsRBDs are critical for DRB4 function. Our biochemical approach and observations clearly show that DRB4 is specifically required for DCL4 activity in vitro. 相似文献
977.
The objective of this study was to determine whether immunization of Mozambique tilapia with different Cryptocaryon irritans i-antigen serotypes elicited cross-protection against challenge infection by both serotypes. Fish were directly exposed to live theronts of isolate W1 or isolate K1, that express different surface i-antigens. There was no significant difference in the number of trophonts infecting the fish between the two isolates, W1 and K1, following primary exposure. Serum from immunized fish exposed to live theronts showed higher immobilization titres and ELISA values against homologous isolates than to heterologous isolates after the primary exposure. However, mucus antibody did not immobilize theronts although the ELISA results clearly indicated that mucus antibodies recognizing C. irritans were generated. In a study with Western blot analyses, serum antibodies recognized only an antigen of the corresponding serotype and no proteins common to both serotypes were identified. Sequence analyses of 754 bases of rDNA nucleotide sequence including complete nuclear ribosomal ITS-1–5.8S rDNA–ITS-2 region were conducted and found to be identical for W1- and K1-isolates. These findings confirmed that both isolates were members of the species, C. irritans, and that rDNA analysis would not distinguish the two isolates. In conclusion, despite the fact that the immobilization assays and ELISA detected two serotypes in vitro, challenge assays provided evidence for only one type of C. irritans. 相似文献
978.
Sato M Yoshimura S Hirai R Goto A Kunii M Atik N Sato T Sato K Harada R Shimada J Hatabu T Yorifuji H Harada A 《Traffic (Copenhagen, Denmark)》2011,12(10):1383-1393
VAMP7 or tetanus neurotoxin-insensitive vesicle- associated membrane protein (TI-VAMP) has been proposed to regulate apical transport in polarized epithelial cells, axonal transport in neurons and lysosomal exocytosis. To investigate the function of VAMP7 in vivo, we generated VAMP7 knockout mice. Here, we show that VAMP7 knockout mice are indistinguishable from control mice and display a similar localization of apical proteins in the kidney and small intestine and a similar localization of axonal proteins in the nervous system. Neurite outgrowth of cultured mutant hippocampal neurons was reduced in mutant neurons. However, lysosomal exocytosis was not affected in mutant fibroblasts. Our results show that VAMP7 is required in neurons to extend axons to the full extent. However, VAMP7 does not seem to be required for epithelial cell polarity and lysosomal exocytosis. 相似文献
979.
Kazuko Norisada Hidekazu Tanaka Tetsuari Onishi Akihiro Kaneko Takayuki Tsuji Kohei Yamawaki Keiko Ryo Kazuhiro Tatsumi Kensuke Matsumoto Natsuko Miura Jun Saegusa Yukiko Morinaga Shigeo Hara Hiroya Kawai Ken-ichi Hirata 《Cardiovascular ultrasound》2011,9(1):1-4
We report a case of a 52-year-old patient with dilated cardiomyopathy who presented with worsening heart failure. Two-dimensional transthoracic echocardiography and real-time three dimensional transthoracic echocardiography showed severe dilated cardiac chambers, impaired ejection fraction and a mobile right atrial thrombus 2.6 × 1.0 cm in size, traversing the right atrial cavity during the whole cardiac cycle. After one week therapeutic anticoagulation, echocardiography confirmed no evidence of residual thrombus. 相似文献
980.
Fumimasa Nomura Tomoyuki Kaneko Akihiro Hattori Kenji Yasuda 《Journal of nanobiotechnology》2011,9(1):1-5