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31.
Waisum Ma Stephen L. Brusatte Junchang Lü Manabu Sakamoto 《Journal of evolutionary biology》2020,33(2):178-188
Oviraptorosaurs are bird‐like theropod dinosaurs that thrived in the final pre‐extinction ecosystems during the latest Cretaceous, and the beaked, toothless skulls of derived species are regarded as some of the most peculiar among dinosaurs. Their aberrant morphologies are hypothesized to have been caused by rapid evolution triggered by an ecological/biological driver, but little is known about how their skull shapes and functional abilities diversified. Here, we use quantitative techniques to study oviraptorosaur skull form and mandibular function. We demonstrate that the snout is particularly variable, that mandibular form and upper/lower beak form are significantly correlated with phylogeny, and that there is a strong and significant correlation between mandibular function and mandible/lower beak shape, suggesting a form–function association. The form–function relationship and phylogenetic signals, along with a moderate allometric signal in lower beak form, indicate that similar mechanisms governed beak shape in oviraptorosaurs and extant birds. The two derived oviraptorosaur clades, oviraptorids and caenagnathids, are significantly separated in morphospace and functional space, indicating that they partitioned niches. Oviraptorids coexisting in the same ecosystem are also widely spread in morphological and functional space, suggesting that they finely partitioned feeding niches, whereas caenagnathids exhibit extreme disparity in beak size. The diversity of skull form and function was likely key to the diversification and evolutionary success of oviraptorosaurs in the latest Cretaceous. 相似文献
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33.
Kume Manabu Nakayama Naoki Iwasaki Yasunari Hori Tomoya Watanabe Shun Terashima Yuki Medo Ayano Arai Nobuaki Yamashita Yoh Mitamura Hiromichi 《Environmental Biology of Fishes》2021,104(4):529-533
Environmental Biology of Fishes - Eel movement patterns have been frequently studied to learn about their movements within the fresh- and brackish waters of the same river before their spawning... 相似文献
34.
Endo Yuta Allam Ayman Natsuike Masafumi Yoshimura Chihiro Fujii Manabu 《Landscape and Ecological Engineering》2021,17(2):75-84
Landscape and Ecological Engineering - This study investigated the export of dissolved iron (DFe) from river catchments with emphasis on land use and land cover (LULC). The DFe concentrations were... 相似文献
35.
Takafumi Watanabe Hideaki Nanamiya Manabu Kojima Shinji Nomura Shigenori Furukawa Shu Soeda Daisuke Tanaka Takao Isogai Jun-ichi Imai Shinya Watanabe Keiya Fujimori 《Translational oncology》2021,14(3):101010
PurposeEndometrial carcinoma (EC) is a clinically heterogeneous disease characterized by a number of different histological subtypes, and its heterogeneity may be involved in the accumulation of multiple genetic alterations. The aim of this work was to investigate the comprehensive mutational profile of EC tumors, and examine the associations between somatic mutations and clinicopathological features or survival in EC patients.MethodsA total of 100 surgical tumors were obtained from EC patients who had previously undergone surgery. Genomic DNA samples extracted from fresh-frozen tissues were analyzed using the Ion AmpliSeq Cancer Hotspot Panel v2 Kit, covering 50 tumor-related genes.ResultsValidated mutations were detected in 91 of the 100 tumors (91%) and identified in eight of the most frequently mutated genes, namely PTEN (57%), PIK3CA (51%), TP53 (30%), KRAS (23%), CTNNB1 (21%), FBFR2 (13%), FBXW7(10%) and RB1 (9%). PTEN mutations were found to associated with young age (< 60), early-stage, endometrioid histology, non-recurrence and better overall survival (OS). CTNNB1 mutations were associated with young age, endometrioid histology and better OS. On the other hands, TP53 mutations were associated with late-stage, non-endometrioid histology, high-grade, recurrence and worse OS. FBWX7 mutations were associated with late-stage, vascular invasion and lymph node metastasis. FGFR2 mutations correlated with deep (≥ 1/2) myometrial invasion.ConclusionOur comprehensive mutational profile will be useful for understanding and evaluating the molecular characteristics of EC tumors, and may lead to the establishment of novel treatment strategies that improve the survival of patients with EC in the future. 相似文献
36.
Sachiko N. Isobe Hideki Hirakawa Shusei Sato Fumi Maeda Masami Ishikawa Toshiki Mori Yuko Yamamoto Kenta Shirasawa Mitsuhiro Kimura Masanobu Fukami Fujio Hashizume Tomoko Tsuji Shigemi Sasamoto Midori Kato Keiko Nanri Hisano Tsuruoka Chiharu Minami Chika Takahashi Tsuyuko Wada Akiko Ono Kumiko Kawashima Naomi Nakazaki Yoshie Kishida Mitsuyo Kohara Shinobu Nakayama Manabu Yamada Tsunakazu Fujishiro Akiko Watanabe Satoshi Tabata 《DNA research》2013,20(1):79-92
37.
Tsutomu Shimura Yasushi Ochiai Naoto Noma Toshiyuki Oikawa Yui Sano Manabu Fukumoto 《Cell cycle (Georgetown, Tex.)》2013,12(5):773-782
Fractionated radiotherapy (RT) is widely used in cancer treatment, because it preserves normal tissues. However, repopulation of radioresistant tumors during fractionated RT limits the efficacy of RT. We recently demonstrated that a moderate level of long-term fractionated radiation confers acquired radioresistance to tumor cells, which is caused by DNA-PK/AKT/GSK3β-mediated cyclin D1 overexpression. The resulting cyclin D1 overexpression leads to forced progression of the cell cycle to S-phase, concomitant with induction of DNA double-strand breaks (DSBs). In this study, we investigated the molecular mechanisms underlying cyclin D1 overexpression-induced DSBs during DNA replication in acquired radioresistant cells. DNA fiber data demonstrated that replication forks progressed slowly in acquired radioresistant cells compared with corresponding parental cells in HepG2 and HeLa cell lines. Slowly progressing replication forks were also observed in HepG2 and HeLa cells that overexpressed a nondegradable cyclin D1 mutant. We also found that knockdown of Mus81endonuclease, which is responsible for resolving aberrant replication forks, suppressed DSB formation in acquired radioresistant cells. Consequently, Mus81 created DSBs to remove aberrant replication forks in response to replication perturbation triggered by cyclin D1 overexpression. After treating cells with a specific inhibitor for DNA-PK or ATM, apoptosis rates increased in acquired radioresistant cells but not in parental cells by inhibiting the DNA damage response to cyclin D1-mediated DSBs. This suggested that these inhibitors might eradicate acquired radioresistant cells and improve fractionated RT outcomes. 相似文献
38.
Shintaro Kobayashi Tadaki Suzuki Manabu Igarashi Yasuko Orba Noriko Ohtake Keita Nagakawa Kenichi Niikura Takashi Kimura Harumi Kasamatsu Hirofumi Sawa 《PloS one》2013,8(10)
The capsid of the human polyomavirus JC virus (JCV) consists of 72 pentameric capsomeres of a major structural protein, Vp1. The cysteine residues of the related Vp1 of SV40 are known to contribute to Vp1 folding, pentamer formation, pentamer-pentamer contacts, and capsid stabilization. In light of the presence of a slight structural difference between JCV Vp1 and SV40 counterpart, the way the former folds could be either different from or similar to the latter. We found a difference: an important contribution of Vp1 cysteines to the formation of infectious virions, unique in JCV and absent in SV40. Having introduced amino acid substitution at each of six cysteines (C42, C80, C97, C200, C247, and C260) in JCV Vp1, we found that, when expressed in HeLa cells, the Vp1 level was decreased in C80A and C247A mutants, and remained normal in the other mutants. Additionally, the C80A and C247A Vp1-expressing cell extracts did not show the hemagglutination activity characteristic of JCV particles. The C80A and C247A mutant Vp1s were found to be less stable than the wild-type Vp1 in HeLa cells. When produced in a reconstituted in vitro protein translation system, these two mutant proteins were stable, suggesting that some cellular factors were responsible for their degradation. As determined by their sucrose gradient sedimentation profiles, in vitro translated C247A Vp1 formed pentamers, but in vitro translated C80A Vp1 was entirely monomeric. When individually incorporated into the JCV genome, the C80A and C247A mutants, but not the other Vp1 cysteine residues mutants, interfered with JCV infectivity. Furthermore, the C80A, but not the C247A, mutation prevented the nuclear localization of Vp1 in JCV genome transfected cells. These findings suggest that C80 of JCV Vp1 is required for Vp1 stability and pentamer formation, and C247 is involved in capsid assembly in the nucleus. 相似文献
39.
The emergence of the occipital alpha rhythm on brain electroencephalogram (EEG) is associated with brain activity in the cerebral neocortex and deep brain structures. To further understand the mechanisms of alpha rhythm power fluctuation, we performed simultaneous EEGs and functional magnetic resonance imaging recordings in human subjects during a resting state and explored the dynamic relationship between alpha power fluctuation and blood oxygenation level-dependent (BOLD) signals of the brain. Based on the frequency characteristics of the alpha power time series (APTS) during 20-minute EEG recordings, we divided the APTS into two components: fast fluctuation (0.04–0.167 Hz) and slow fluctuation (0–0.04 Hz). Analysis of the correlation between the MRI signal and each component revealed that the slow fluctuation component of alpha power was positively correlated with BOLD signal changes in the brain stem and the medial part of the thalamus and anterior cingulate cortex, while the fast fluctuation component was correlated with the lateral part of the thalamus and the anterior cingulate cortex, but not the brain stem. In summary, these data suggest that different subcortical structures contribute to slow and fast modulations of alpha spectra on brain EEG. 相似文献
40.
Yasuhito Hamaguchi Manabu Fujimoto Takashi Matsushita Kenzo Kaji Kazuhiro Komura Minoru Hasegawa Masanari Kodera Eiji Muroi Keita Fujikawa Mariko Seishima Hidehiro Yamada Ryo Yamada Shinichi Sato Kazuhiko Takehara Masataka Kuwana 《PloS one》2013,8(4)