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241.
Expression of extensin genes is dependent on the stage of the cell cycle and cell proliferation in suspension-cultured Catharanthus roseus cells 总被引:2,自引:0,他引:2
Ito Masaki Kodama Hiroaki Komamine Atsushi Watanabe Akira 《Plant molecular biology》1998,36(3):343-351
To isolate cDNAs expressed at a specific phase of the cell cycle in a higher plant, we performed differential screening of a cDNA library prepared from the S-phase cells of synchronized cultures of Catharanthus roseus. Sequence analysis shows that two of the identified cDNAs, cyc15 and cyc17, encode extensins that represent a family of cell wall hydroxyproline-rich glycoproteins. Protein sequences deduced from the two cDNAs contain the characteristic pentapeptide repeat sequence, Ser-Pro-Pro-Pro-Pro, which is commonly observed in extensins. The protein sequences also share several other extensin characteristics such as the presence of a N-terminal signal peptide and a high content of Tyr and Lys residues. When C. roseus cell suspension cultures were synchronized by phosphate starvation, the mRNAs of both cyc15 and cyc17 were transiently expressed during the S and G2 phases of the cell cycle. However, significant amounts of the mRNAs also accumulated in phosphate-starved cells arrested in the G1 phase. In asynchronous cultures, both genes were expressed during the stationary phase, when cell proliferation ceased. The observed patterns of expression suggest that the extensin genes, cyc15 and cyc17, are under two types of regulation: one that depends on the stage of the cell cycle and another that is induced during the growth arrest. Thus, the products of these genes may function both during the progression through the cell cycle and in the strengthening of the cell wall after cell division. 相似文献
242.
243.
Masato Yuasa Tsuyoshi Yamada Takashi Taniyama Tomokazu Masaoka Wei Xuetao Toshitaka Yoshii Masaki Horie Hiroaki Yasuda Toshimasa Uemura Atsushi Okawa Shinichi Sotome 《PloS one》2015,10(2)
We evaluated whether dexamethasone augments the osteogenic capability of bone marrow-derived stromal cells (BMSCs) and muscle tissue-derived stromal cells (MuSCs), both of which are thought to contribute to ectopic bone formation induced by bone morphogenetic protein-2 (BMP-2), and determined the underlying mechanisms. Rat BMSCs and MuSCs were cultured in growth media with or without 10-7 M dexamethasone and then differentiated under osteogenic conditions with dexamethasone and BMP-2. The effects of dexamethasone on cell proliferation and osteogenic differentiation, and also on ectopic bone formation induced by BMP-2, were analyzed. Dexamethasone affected not only the proliferation rate but also the subpopulation composition of BMSCs and MuSCs, and subsequently augmented their osteogenic capacity during osteogenic differentiation. During osteogenic induction by BMP-2, dexamethasone also markedly affected cell proliferation in both BMSCs and MuSCs. In an in vivo ectopic bone formation model, bone formation in muscle-implanted scaffolds containing dexamethasone and BMP-2 was more than two fold higher than that in scaffolds containing BMP-2 alone. Our results suggest that dexamethasone potently enhances the osteogenic capability of BMP-2 and may thus decrease the quantity of BMP-2 required for clinical application, thereby reducing the complications caused by excessive doses of BMP-2.Highlights: 1. Dexamethasone induced selective proliferation of bone marrow- and muscle-derived cells with higher differentiation potential. 2. Dexamethasone enhanced the osteogenic capability of bone marrow- and muscle-derived cells by altering the subpopulation composition. 3. Dexamethasone augmented ectopic bone formation induced by bone morphogenetic protein-2. 相似文献
244.
Hirohito Mori Hideki Kobara Takaaki Tsushimi Noriko Nishiyama Shintaro Fujihara Tsutomu Masaki 《PloS one》2015,10(4)
Objective
Objective evaluation of resected specimen and tumor size is critical because the tumor diameter after endoscopic submucosal dissection affects therapeutic strategies. In this study, we investigated whether the true tumor diameter of gastrointestinal cancer specimens measured by flexible endoscopy is subjective by testing whether the specimen is correctly attached to the specimen board after endoscopic submucosal dissection resection and whether the size differs depending on the endoscopist who attached the specimen.Methods
Seventy-two patients diagnosed with early gastric cancer who satisfied the endoscopic submucosal dissection expanded-indication guideline were enrolled. Three endoscopists were randomly selected before every endoscopic submucosal dissection. Each endoscopist separately attached the same resected specimen, measured the maximum resection diameter and tumor size, and removed the lesion from the attachment board.Results
The resected specimen diameters of the 3 endoscopists were 44.5±13.9 mm (95% Confidence Interval (CI): 23–67), 37.4±12.0 mm (95% CI: 18–60), and 41.1±13.3 mm (95% CI: 20–63) mm. Comparison among 3 groups (Kruskal Wallis H- test), there were significant differences (H = 6.397, P = 0.040), and recorded tumor sizes were 38.3±13.1 mm (95% CI: 16–67), 31.1±11.2 mm (95% CI: 12.5–53.3), and 34.8±12.8 (95% CI: 11.5–62.3) mm. Comparison among 3 groups, there were significant differences (H = 6.917, P = 0.031).Conclusions
Human errors regarding the size of attached resected specimens are unavoidable, but it cannot be ignored because it affects the patient’s additional treatment and/or surgical intervention. We must develop a more precise methodology to obtain accurate tumor size.Trial Registration
University hospital Medical Information Network UMIN No. 000012915 相似文献245.
Tanapan Siangcham Piyachat Chansela Takahiro Hayasaka Noritaka Masaki Morakot Sroyraya Jaruwan Poljaroen Saowaros Suwansa-ard Attakorn Engsusophon Peter J. Hanna Prasert Sobhon Mitsutoshi Setou 《PloS one》2015,10(3)
Testis maturation, germ cell development and function of sperm, are related to lipid composition. Phosphatidylcholines (PCs) play a key role in the structure and function of testes. As well, increases of polyunsaturated fatty acids (PUFA) and highly unsaturated fatty acids (HUFA), especially arachidonic acid (ARA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) are essential for male fertility. This study is the first report to show the composition and distribution of PCs and total fatty acids (FAs) in three groups of seminiferous tubules (STs) classified by cellular associations [i.e., A (STs with mostly early germ cells), B (STs with mostly spermatids), and C (STs with spermatozoa)], in three morphotypes of Macrobrachium rosenbergii, [i.e., small male (SM), orange claw male (OC), and blue claw male (BC)]. Thin layer chromatography exhibited levels of PCs reaching maxima in STs of group B. Imaging mass spectrometry showed remarkably high signals corresponding to PC (16:0/18:1), PC (18:0/18:2), PC (18:2/20:5), and PC (16:0/22:6) in STs of groups A and B. Moreover, most signals were detected in the early developing cells and the intertubular area, but not at the area containing spermatozoa. Finally, gas chromatography-mass spectrometry indicated that the major FAs present in the testes were composed of 14:0, 16:0, 17:0, 18:0, 16:1, 18:1, 18:2, 20:1, 20:2, 20:4, 20:5, and 22:6. The testes of OC contained the greatest amounts of these FAs while the testes of BC contained the least amounts of these FAs, and there was more EPA (20:5) in the testes of SM and OC than those in the BC. The increasing amounts of FAs in the SM and OC indicate that they are important for spermatogenesis and spermiogenesis. This knowledge will be useful in formulating diets containing PUFA and HUFA for prawn broodstocks in order to improve testis development, and lead to increased male fecundity. 相似文献
246.
Glucagon-like peptide-1 (GLP-1) is an incretin hormone secreted from enteroendocrine L-cells. Although several nutrients induce GLP-1 secretion, there is little evidence to suggest that non-nutritive compounds directly increase GLP-1 secretion. Here, we hypothesized that anthocyanins induce GLP-1 secretion and thereby significantly contribute to the prevention and treatment of diabetes. Delphinidin 3-rutinoside (D3R) was shown to increase GLP-1 secretion in GLUTag L cells. The results suggested that three hydroxyl or two methoxyl moieties on the aromatic ring are essential for the stimulation of GLP-1 secretion. Notably, the rutinose moiety was shown to be a potent enhancer of GLP-1 secretion, but only in conjunction with three hydroxyl moieties on the aromatic ring (D3R). Receptor antagonist studies revealed that D3R-stimulates GLP-1 secretion involving inositol 1,4,5-trisphosphate receptor-mediated intracellular Ca2+ mobilization. Treatment of GLUTag cells with a Ca2+/calmodulin-dependent kinaseII (CaMKII) inhibitor (KN-93) abolished D3R-stimulated GLP-1 secretion. In addition, treatment of GLUTag cells with D3R resulted in activation of CaMKII. Pre-treatment of cells with a G protein-coupled receptor (GPR) 40/120 antagonist (GW1100) also significantly decreased D3R-stimulated GLP-1 secretion. These observations suggest that D3R stimulates GLP-1 secretion in GLUTag cells, and that stimulation of GLP-1 secretion by D3R is mediated via Ca2+-CaMKII pathway, which may possibly be mediated by GPR40/120. These findings provide a possible molecular mechanism of GLP-1 secretion in intestinal L-cells mediated by foods or drugs and demonstrate a novel biological function of anthocyanins in regards to GLP-1 secretion. 相似文献
247.
Michele Carbone Erin G. Flores Mitsuru Emi Todd A. Johnson Tatsuhiko Tsunoda Dusty Behner Harriet Hoffman Mary Hesdorffer Masaki Nasu Andrea Napolitano Amy Powers Michael Minaai Francine Baumann Peter Bryant-Greenwood Olivia Lauk Michaela B. Kirschner Walter Weder Isabelle Opitz Harvey I. Pass Giovanni Gaudino Sandra Pastorino Haining Yang 《PLoS genetics》2015,11(12)
We recently discovered an inherited cancer syndrome caused by BRCA1-Associated Protein 1 (BAP1) germline mutations, with high incidence of mesothelioma, uveal melanoma and other cancers and very high penetrance by age 55. To identify families with the BAP1 cancer syndrome, we screened patients with family histories of multiple mesotheliomas and melanomas and/or multiple cancers. We identified four families that shared an identical BAP1 mutation: they lived across the US and did not appear to be related. By combining family histories, molecular genetics, and genealogical approaches, we uncovered a BAP1 cancer syndrome kindred of ~80,000 descendants with a core of 106 individuals, whose members descend from a couple born in Germany in the early 1700s who immigrated to North America. Their descendants spread throughout the country with mutation carriers affected by multiple malignancies. Our data show that, once a proband is identified, extended analyses of these kindreds, using genomic and genealogical studies to identify the most recent common ancestor, allow investigators to uncover additional branches of the family that may carry BAP1 mutations. Using this knowledge, we have identified new branches of this family carrying BAP1 mutations. We have also implemented early-detection strategies that help identify cancers at early-stage, when they can be cured (melanomas) or are more susceptible to therapy (MM and other malignancies). 相似文献
248.
Ryosuke Tateishi Nobuko Akiyama Maki Miyauchi Riko Yoshinaga Hiroki Sasanuma Takashi Kudo Miki Shimbo Masahiro Shinohara Koji Obata Jun-ichiro Inoue Masaki Shirakawa Dai Shiba Hiroshi Asahara Nobuaki Yoshida Satoru Takahashi Hironobu Morita Taishin Akiyama 《PloS one》2015,10(10)
Gravity change affects many immunological systems. We investigated the effects of hypergravity (2G) on murine thymic cells. Exposure of mice to 2G for three days reduced the frequency of CD4+CD8+ thymocytes (DP) and mature medullary thymic epithelial cells (mTECs), accompanied by an increment of keratin-5 and keratin-8 double-positive (K5+K8+) TECs that reportedly contain TEC progenitors. Whereas the reduction of DP was recovered by a 14-day exposure to 2G, the reduction of mature mTECs and the increment of K5+K8+ TEC persisted. Interestingly, a surgical lesion of the inner ear’s vestibular apparatus inhibited these hypergravity effects. Quantitative PCR analysis revealed that the gene expression of Aire and RANK that are critical for mTEC function and development were up-regulated by the 3-day exposure and subsequently down-regulated by the 14-day exposure to 2G. Unexpectedly, this dynamic change in mTEC gene expression was independent of the vestibular apparatus. Overall, data suggest that 2G causes a temporary reduction of DP and a persistent reduction of mature mTECs in a vestibular system-dependent manner, and also dysregulates mTEC gene expression without involving the vestibular system. These data might provide insight on the impact of gravity change on thymic functions during spaceflight and living. 相似文献
249.
We examined the relationship between the community structure of wood-decaying fungi, detected by high-throughput sequencing, and the decomposition rate using 13 years of data from a forest dynamics plot. For molecular analysis and wood density measurements, drill dust samples were collected from logs and stumps of Fagus and Quercus in the plot. Regression using a negative exponential model between wood density and time since death revealed that the decomposition rate of Fagus was greater than that of Quercus. The residual between the expected value obtained from the regression curve and the observed wood density was used as a decomposition rate index. Principal component analysis showed that the fungal community compositions of both Fagus and Quercus changed with time since death. Principal component analysis axis scores were used as an index of fungal community composition. A structural equation model for each wood genus was used to assess the effect of fungal community structure traits on the decomposition rate and how the fungal community structure was determined by the traits of coarse woody debris. Results of the structural equation model suggested that the decomposition rate of Fagus was affected by two fungal community composition components: one that was affected by time since death and another that was not affected by the traits of coarse woody debris. In contrast, the decomposition rate of Quercus was not affected by coarse woody debris traits or fungal community structure. These findings suggest that, in the case of Fagus coarse woody debris, the fungal community structure is related to the decomposition process of its host substrate. Because fungal community structure is affected partly by the decay stage and wood density of its substrate, these factors influence each other. Further research on interactive effects is needed to improve our understanding of the relationship between fungal community structure and the woody debris decomposition process. 相似文献
250.
Shin-ichi Takenaka Shinjiro Kaieda Tomotaka Kawayama Masanobu Matsuoka Yoichiro Kaku Takashi Kinoshita Yuki Sakazaki Masaki Okamoto Masaki Tominaga Katsuya Kanesaki Asako Chiba Sachiko Miyake Hiroaki Ida Tomoaki Hoshino 《Biochemistry and Biophysics Reports》2015
The newly characterized cytokine IL-38 (IL-1F10) belongs to the IL-1 family of cytokines. Previous work has demonstrated that IL-38 inhibited Candida albicans-induced IL-17 production from peripheral blood mononuclear cells. However, it is still unclear whether IL-38 is an inflammatory or an anti-inflammatory cytokine. We generated anti-human IL-38 monoclonal antibodies in order to perform immunohistochemical staining and an enzyme-linked immunosorbent assay. While human recombinant IL-38 protein was not cleaved by recombinant caspase-1, chymase, or PR3 in vitro, overexpression of IL-38 cDNA produced a soluble form of IL-38 protein. Furthermore, immunohistochemical analysis showed that synovial tissues obtained from RA patients strongly expressed IL-38 protein. To investigate the biological role of IL-38, C57BL/6 IL-38 gene-deficient (?/?) mice were used in an autoantibody-induced rheumatoid arthritis (RA) mouse model. As compared with control mice, IL-38 (?/?) mice showed greater disease severity, accompanied by higher IL-1β and IL-6 gene expression in the joints. Therefore, IL-38 acts as an inhibitor of the pathogenesis of autoantibody-induced arthritis in mice and may have a role in the development or progression of RA in humans. 相似文献