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981.
Vo Nguyen Trung Hiroshi Yamamoto Akira Furukawa Tsuyoshi Yamaguchi Satoshi Murata Masahiro Yoshimura Yoko Murakami Shigetaka Sato Hideji Otani Satoshi Ugi Katsutaro Morino Hiroshi Maegawa Tohru Tani 《PloS one》2013,8(6)
Background
Enhanced secretion of glucagon-like peptide-1 (GLP-1) has been suggested as a possible mechanism underlying the improvement in type 2 diabetes mellitus (T2DM) after laparoscopic sleeve gastrectomy (LSG). However, the reason for enhanced GLP-1 secretion during glucose challenge after LSG remains unclear because LSG does not include intestinal bypass. In this study, we focused on the effects of LSG on GLP-1 secretion and intestinal motility during the oral glucose tolerance test (OGTT) using cine magnetic resonance imaging (MRI) before and 3 months after LSG.Methods
LSG was performed in 12 obese patients with a body mass index >35 kg/m2. Six patients had T2DM. OGTT was performed before and 3 months after the surgery. Body weight, hemoglobin A1c (HbA1c), and GLP-1 levels during OGTT were examined, and intestinal motility during OGTT was assessed using cine MRI.Results
Body weight was significantly decreased after surgery in all the cases. HbA1c was markedly decreased in all the diabetic subjects. In all cases, GLP-1 secretion during OGTT was enhanced and cine MRI showed markedly increased intestinal motility at 15 and 30 min during OGTT after LSG.Conclusions
LSG leads to accelerated intestinal motility and reduced intestinal transit time, which may be involved in the mechanism underlying enhanced GLP-1 secretion during OGTT after LSG. 相似文献982.
Koichiro Saito Koji Inagaki Takahiro Kamimoto Yoko Ito Toshiaki Sugita Satoko Nakajo Akira Hirasawa Arifumi Iwamaru Takashi Ishikura Hideki Hanaoka Keisuke Okubo Tokio Onozaki Takeru Zama 《PloS one》2013,8(8)
Background
MicroRNA (miRNA) is an emerging subclass of small non-coding RNAs that regulates gene expression and has a pivotal role for many physiological processes including cancer development. Recent reports revealed the role of miRNAs as ideal biomarkers and therapeutic targets due to their tissue- or disease-specific nature. Head and neck cancer (HNC) is a major cause of cancer-related mortality and morbidity, and laryngeal cancer has the highest incidence in it. However, the molecular mechanisms involved in laryngeal cancer development remain to be known and highly sensitive biomarkers and novel promising therapy is necessary.Methodology/Principal Findings
To explore laryngeal cancer-specific miRNAs, RNA from 5 laryngeal surgical specimens including cancer and non-cancer tissues were hybridized to microarray carrying 723 human miRNAs. The resultant differentially expressed miRNAs were further tested by using quantitative real time PCR (qRT-PCR) on 43 laryngeal tissue samples including cancers, noncancerous counterparts, benign diseases and precancerous dysplasias. Significant expressional differences between matched pairs were reproduced in miR-133b, miR-455-5p, and miR-196a, among which miR-196a being the most promising cancer biomarker as validated by qRT-PCR analyses on additional 84 tissue samples. Deep sequencing analysis revealed both quantitative and qualitative deviation of miR-196a isomiR expression in laryngeal cancer. In situ hybridization confirmed laryngeal cancer-specific expression of miR-196a in both cancer and cancer stroma cells. Finally, inhibition of miR-196a counteracted cancer cell proliferation in both laryngeal cancer-derived cells and mouse xenograft model.Conclusions/Significance
Our study provided the possibilities that miR-196a might be very useful in diagnosing and treating laryngeal cancer. 相似文献983.
Masazumi Nishimoto Miyuki Katano Toshiyuki Yamagishi Tomoaki Hishida Masayoshi Kamon Ayumu Suzuki Masataka Hirasaki Yoko Nabeshima Yo-ichi Nabeshima Yukako Katsura Yoko Satta Janine E. Deakin Jennifer A. Marshall Graves Yoko Kuroki Ryuichi Ono Fumitoshi Ishino Masatsugu Ema Satoru Takahashi Hidemasa Kato Akihiko Okuda 《PloS one》2013,8(7)
Embryogenesis in placental mammals is sustained by exquisite interplay between the embryo proper and placenta. UTF1 is a developmentally regulated gene expressed in both cell lineages. Here, we analyzed the consequence of loss of the UTF1 gene during mouse development. We found that homozygous UTF1 mutant newborn mice were significantly smaller than wild-type or heterozygous mutant mice, suggesting that placental insufficiency caused by the loss of UTF1 expression in extra-embryonic ectodermal cells at least in part contributed to this phenotype. We also found that the effects of loss of UTF1 expression in embryonic stem cells on their pluripotency were very subtle. Genome structure and sequence comparisons revealed that the UTF1 gene exists only in placental mammals. Our analyses of a family of genes with homology to UTF1 revealed a possible mechanism by which placental mammals have evolved the UTF1 genes. 相似文献
984.
Alejandrina Cristia Emmanuel Dupoux Yoko Hakuno Sarah Lloyd-Fox Manuela Schuetze José Kivits Tomas Bergvelt Marjolijn van Gelder Luca Filippin Sylvain Charron Yasuyo Minagawa-Kawai 《PloS one》2013,8(3)
Until recently, imaging the infant brain was very challenging. Functional Near InfraRed Spectroscopy (fNIRS) is a promising, relatively novel technique, whose use is rapidly expanding. As an emergent field, it is particularly important to share methodological knowledge to ensure replicable and robust results. In this paper, we present a community-augmented database which will facilitate precisely this exchange. We tabulated articles and theses reporting empirical fNIRS research carried out on infants below three years of age along several methodological variables. The resulting spreadsheet has been uploaded in a format allowing individuals to continue adding new results, and download the most recent version of the table. Thus, this database is ideal to carry out systematic reviews. We illustrate its academic utility by focusing on the factors affecting three key variables: infant attrition, the reliability of oxygenated and deoxygenated responses, and signal-to-noise ratios. We then discuss strengths and weaknesses of the DBIfNIRS, and conclude by suggesting a set of simple guidelines aimed to facilitate methodological convergence through the standardization of reports. 相似文献
985.
Yoko Arakaki Hiroko Kawai-Toyooka Yuki Hamamura Tetsuya Higashiyama Akira Noga Masafumi Hirono Bradley J. S. C. Olson Hisayoshi Nozaki 《PloS one》2013,8(12)
Volvocine green algae represent the “evolutionary time machine” model lineage for studying multicellularity, because they encompass the whole range of evolutionary transition of multicellularity from unicellular Chlamydomonas to >500-celled Volvox. Multicellular volvocalean species including Gonium pectorale and Volvox carteri generally have several common morphological features to survive as integrated multicellular organisms such as “rotational asymmetry of cells” so that the cells become components of the individual and “cytoplasmic bridges between protoplasts in developing embryos” to maintain the species-specific form of the multicellular individual before secretion of new extracellular matrix (ECM). However, these morphological features have not been studied in the four-celled colonial volvocine species Tetrabaena socialis that is positioned in the most basal lineage within the colonial or multicellular volvocine greens. Here we established synchronous cultures of T. socialis and carried out immunofluorescence microscopic and ultrastructural observations to elucidate these two morphological attributes. Based on immunofluorescence microscopy, four cells of the mature T. socialis colony were identical in morphology but had rotational asymmetry in arrangement of microtubular rootlets and separation of basal bodies like G. pectorale and V. carteri. Ultrastructural observations clearly confirmed the presence of cytoplasmic bridges between protoplasts in developing embryos of T. socialis even after the formation of new flagella in each daughter protoplast within the parental ECM. Therefore, these two morphological attributes might have evolved in the common four-celled ancestor of the colonial volvocine algae and contributed to the further increase in cell number and complexity of the multicellular individuals of this model lineage. T. socialis is one of the simplest integrated multicellular organisms in which four identical cells constitute the individual. 相似文献
986.
Previous results demonstrated that capsaicin induces the reversible tight junctions (TJ) opening via cofilin activation. The present study investigated the mechanisms underlying the reversible TJ opening and compared the effect to the irreversible opening induced by actin inhibitors. Capsaicin treatment induced the F-actin alteration unique to capsaicin compared to actin-interacting agents such as latrunculin A, which opens TJ irreversibly. Along with TJ opening, capsaicin decreased the level of F-actin at bicellular junctions but increased it at tricellular junctions accompanied with its concentration on the apical side of the lateral membrane. No change in TJ protein localization was observed upon exposure to capsaicin, but the amount of occludin was decreased significantly. In addition, cosedimentation analyses suggested a decrease in the interactions forming TJ, thereby weakening TJ tightness. Introduction of cofilin, LIMK and occludin into the cell monolayers confirmed their contribution to the transepithelial electrical resistance decrease. Finally, exposure of monolayers to capsaicin augmented the paracellular passage of both charged and uncharged compounds, as well as of insulin, indicating that capsaicin can be employed to modulate epithelial permeability. Our results demonstrate that capsaicin induces TJ opening through a unique mechanism, and suggest that it is a new type of paracellular permeability enhancer. 相似文献
987.
Studies on coral communities have typically been conducted in shallow waters (∼5 m). However, in the face of climate change, and as shallow coral communities become degraded, a greater understanding of deeper coral communities is needed as they become the main reef remnants, playing a central role in the future of coral reefs. To understand the dynamics of deeper coral assemblages, the recruitment and taxonomic composition of different life-stages at 5 and 15 m depths were compared at three locations in Lyudao, southeastern Taiwan in 2010. Coral recruits (<1 cm diameter, <4 months old) were examined using settlement plates. Juvenile corals (1–5 cm, several years old) were examined with quadrats, and adult corals (>5 cm, several years to decades old) were examined using transect lines. Pocilloporid and poritid corals had similar and higher numbers of recruits at 5 m compared to 15 m, whereas acroporid recruits were more abundant at 15 m. The primary cause for the former may be larval behavior, such that they position themselves in shallow waters, while that for the latter may be the dominance of brooding acroporid species (Isopora spp.) at 15 m. The taxonomic composition, especially between recruits and juveniles/adults, was more similar at 15 m than at 5 m. These results suggest a change in the relative importance of pre- and post-settlement processes in assemblage determinants with depth; coral assemblages in shallow habitats (more disturbed) are more influenced by post-settlement processes (mortality events), while those in deeper habitats (more protected) are more influenced by pre-settlement processes (larval supply). 相似文献
988.
Shingo Marumo Masato Katayama Eisaku Komori Yoko Ozaki Masahiro Natsume Satoru Kondo 《Bioscience, biotechnology, and biochemistry》2013,77(7):1967-1968
The effect of oryzalexin D, which has been isolated as a group of novel phytoalexins of rice plant, on DNA, RNA, protein, lipid and chitin biosyntheses, respiration and cell membrane permeability was investigated in Pyricularia oryzae. The concentration for 50% inhibition (ED50) by oryzalexin D of the mycelial growth of P. oryzae was 230 ppm. At this concentration, oryzalexin D inhibited equally the incorporation of [2–14C]thymidine, [2–14C]uridine, l-[U-14C]amino acid mixture, l-[methyl-14C]methionine and d-[l-14C]glucosamine into DNA, RNA, protein, lipid and chitin in intact cells, but did not inhibit these systems in a homogenate of the mycelia of P. oryzae. Oryzalexin D scarcely inhibited the respiration of the homogenate and mitochondria at ED50. On the other hand, oryzalexin D at ED50 caused leakage of potassium and inhibited the uptake of glutamate by mycelial cells of P. oryzae. These results suggest that interference with the cell membrane function is responsible for the primary mode of action.of oryzalexin D against P. oryzae. 相似文献
989.
Tei Yamanishi Akio Kobayashi Yasuko Mikumo Yoko Nakasone Masae Kita Satohiko Hattori 《Bioscience, biotechnology, and biochemistry》2013,77(5):593-598
Constituents of aroma of peel oil (both oleoresin and cold-pressed oil) from Citrus Unshu were isolated by column chromatography and gas chromatography (GLC). and identified mostly by infrared (IR), partially by mass (MS) and nuclear magnetic resonance (NMR) spectroscopy.One hundred and seven compounds were found in the oil and among them, four sesquiterpene hydrocarbons, five acetates, five carbonyls and five alcohols were identified as a main constituents which contributed to difference in flavor from other citrus peel oils. Characteristics of aroma of C. Unshu was discussed on the basis of quantitative analysis. 相似文献
990.
The changes in 13C-NMR and 31P-NMR spectra and 1H-NMR images in soybean cotyledons during germination were investigated. Using 13C-NMR, fatty acid signals in the form of triglycerides were observed in dry seeds, and those were observed approximately 18 days after the start of imbibition. Sucrose signals appeared at 16 hr and disappeared at 5 days. A signal was observed after 5 days, suggesting the activation of membrane metabolism in the cotyledons.31P-NMR signals appeared 2 hr after imbibition before any apparent change in the 13C-NMR spectrum. The peaks identified as sugar phosphate, inorganic phosphate in the cytoplasm and in the vacuole, and an unassigned compound, were distinguishable after 5 days. The vacuole-associated inorganic phosphate peak became prominent 18 days after imbibition in 31P-NMR.Distribution maps of free water indicated that the stored macro-molecular materials which bound water were consumed heterogeneously within the cotyledon. The relaxation time (T1) increased suddenly between 18 days and 23 days after imbibition, which indicates the consumption of stored materials.These findings suggest that cotyledons are the source of such compounds and the energy required for plant growth for approximately 18 days from germination until tri-foliolate leaves begin developing. 相似文献