321 research outputs found
ASO author reflections: Survival benefit of adjuvant chemoradiotherapy for gallbladder cancer: the role of radiation therapy revisited
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Synthesis of new phosphorus ligands for regioselective hydroformylation:
No full textTetraphosphorous ligands with enhanced chelating ability through multiple chelating modes and increased local phosphorus concentration can provide great regioselectivity in Rh/Ligand hydroformylation system. Here we report the synthesis of a series of pyrrole-based tetraphosphorus ligands were synthesized with introducing different functional groups into 3, 3', 5, 5'-positions of the biphenyl, and their applications to the hydroformylation of internal olefins, 1, 5-hexadiene, styrene and its derivatives, and alkyl acrylates.
Internal olefins are cheaper and more readily available feedstock than terminal olefins, the development of highly selective and active isomerization-hydroformylation catalysts for internal olefins is of great importance from economic and energy points of view. In particular, the alkyl-substituted tetraphosphorous ligands gave the best results (for 2-octene, n: i up to 207, for 2-hexene, n: i up to 362).
Double hydroformylation of 1, n-diolefins is a convenient method to produce dialdehydes. The hydroformylation of 1, 5- hexadiene can be achieved with essentially high regioselectivity (linear selectivity is up to 98%).
Styrene and its derivatives prefer the branched aldehydes under the hydro-formylation conditions. However, the linear aldehydes can also be widely used for the production of detergents and plasticizers and important intermediates. Our studies on the hydroformylation of styrene and its derivatives achieved unprecedented high linear selectivity (l/b up to 22 for styrene).
Hydroformylation of alkyl acrylate produces 1, 3- and1, 4-bifunctional compounds, which can be further converted into synthetically useful intermediates. Alkyl acrylates have been hydroformylated to the linear aldehydes with high regioselectivity (linear/branch > 99/1) and extraordinarily high average turnover frequencies (up to 5400 h 1) by using a rhodium complex with a tetraphosphorus ligand. The result is in sharp contrast to the most of other processes that favor production of the branched aldehyde (typically > 95% branched for most Rh-catalyzed reaction systems).M.S.Includes bibliographical referencesby Yu-Ming Chi
College and Research Libraries News, September 2005, Vol. 66 No. 8
No full textThe cover of this issue of ACLR's College and Research Libraries News features Arthur Rackham's The Travellers and the Plane Tree from his 1912 Aesop's Fables. The picture is acknowledged as held in the Carlson Fable Collection of Creighton University's Reinert Alumni Library. There is a short description of the collection on 564.Stephanie Orphan, Editor-in-chie
Author response
No full textDevelopmental potentials of cells are tightly controlled at multiple levels. The embryonic Drosophila airway tree is roughly subdivided into two types of cells with distinct developmental potentials: a proximally located group of multipotent adult precursor cells (P-fate) and a distally located population of more differentiated cells (D-fate). We show that the GATA-family transcription factor (TF) Grain promotes the P-fate and the POU-homeobox TF Ventral veinless (Vvl/Drifter/U-turned) stimulates the D-fate. Hedgehog and receptor tyrosine kinase (RTK) signaling cooperate with Vvl to drive the D-fate at the expense of the P-fate while negative regulators of either of these signaling pathways ensure P-fate specification. Local concentrations of Decapentaplegic/BMP, Wingless/Wnt, and Hedgehog signals differentially regulate the expression of D-factors and P-factors to transform an equipotent primordial field into a concentric pattern of radially different morphogenetic potentials, which gradually gives rise to the distal-proximal organization of distinct cell types in the mature airway.</p
Isotope Composition and Chemical Species of Monthly Precipitation Collected at the Site of a Fusion Test Facility in Japan
No full textThe deuterium plasma experiment was started using the Large Helical Device (LHD) at the National Institute for Fusion Science (NIFS) in March 2017 to investigate high-temperature plasma physics and the hydrogen isotope effects towards the realization of fusion energy. In order to clarify any experimental impacts on precipitation, precipitation has been collected at the NIFS site since November 2013 as a means to assess the relationship between isotope composition and chemical species in precipitation containing tritium. The tritium concentration ranged from 0.10 to 0.61 Bq L−1 and was high in spring and low in summer. The stable isotope composition and the chemical species were unchanged before and after the deuterium plasma experiment. Additionally, the tritium concentration after starting the deuterium plasma experiment was within three sigma of the average tritium concentration before the deuterium plasma experiment. These results suggested that there was no impact by tritium on the environment surrounding the fusion test facility.journal articl
Abstract 5385: Colorectal cancer methylome and laterality
No full textAbstract
Background: Colorectal cancers are anatomically derived from Midgut area (from cecum to mid transverse colon) and Hindgut area (from mid transverse to anal canal). The laterality of colorectal cancers was reported as one of the prognosis markers of these cancers. Midgut originated cancers had statistically poorer overall survivals than Hind gut (Yahagi et al, J Gastrointest Surg, 2016). In addition to clinical reasons, for example its symptomless nature of the bowel obstruction on the right side, the difference of genetic and/or epigenetic profiles between both side colorectal cancers may exists.
Methods: Surgically resected 30 colorectal cancers (Midgut n=9, Hidgut n=21) were included. Any clinicopathological factors except for tumor site was not statistically different between 2 groups. We decided to focus on colon cancer methylome and laterality in this study. Two novel methylation markers of colon cancers (PAX5 and VGF) which were extracted from microarray analysis were used, and quantitative methylation-specific PCR (QMSP) assay was performed for each marker.Results: Both PAX5 and VGF methylations were extremely tumor-specific markers (P&lt;0.001 and P=0.011). Interestingly, Both markers tended to have high methylation frequency in Midgut derived cancers. High frequency of PAX5 promoter methylation was found in 9/9 cases (100%) of Midgut and 15/21 cases (71%) of Hindgut (P=0.141), while that of VGF was found in 6/9 cases (67%) of Midgut and 4/21 cases (19%) of Hindgut (P=0.030). In addition, three multiple colon cancers were found in the cohort. All of them were derived from Midgut area (T1/T1, T3/Tis and T3/Tis), and had high frequency of both PAX5 (2/3, 67%) and VGF (3/3, 100%) methylation.
Conclusion: Cancer methylome between Midgut and Hindgut seemed to be different, and it may affect tumor malignancy, plurality and chemotherapy sensitivity. Now we are in progress of increased colorectal cancer cases (over 100) and methylation markers.
Citation Format: Sho Hirabayashi, Masamichi Hayashi, Goro Nakayama, Keisuke Kurimoto, Hiroshi Tanabe, Mitsuro Kanda, Hideki Takami, Yukiko Niwa, Naoki Iwata, Daisuke Kobayashi, Chie Tanaka, Suguru Yamada, Hiroyuki Sugimoto, Masahiko Koike, Tsutomu Fujii, Michitaka Fujiwara, Yasuhiro Kodera. Colorectal cancer methylome and laterality [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5385. doi:10.1158/1538-7445.AM2017-5385</jats:p
Abstract 3429: Oncogenic function of miR-23b-3p in hepatocellular carcinoma
No full textAbstract
Background: miR-23b has been identified as various cancer-related biomarkers. Interestingly, it works as an oncogenic miRNA in lymphoma, renal cancer and glioma, while it works as a tumor suppressor miRNA in pancreatic cancer, bladder cancer and prostate cancer (Donadeli M et al, Cancer Lett, 2014). We have previously reported miR-23b-3p as a oncomiR in NSCLCs (Begum S, Hayashi M et al, Sci Rep, 2015). To find the correlation to other carcinogenesis, we focused on miR-23b function in hepatocellular carcinoma (HCC).
Methods: miR-23b-3p expression was examined in 9 HCC cell lines (SK-Hep1, HuH2, HLE, PLC/PRF/5, HuH1, HuH7, HLF, Hep3B, HepG2). The downstream of miR-23b-3p overexpression was examined by Cancer Pathway Finder (Qiagen). Results were applied to 125 clinical HCC samples (2002-2011 surgically resected).
Results: Transfection experiments were performed for HepG2 (miR-23b-3p highly expressed) by siRNA and for SK-Hep1 (lowly expressed) by miRNA mimic. Cancer cell proliferation was activated by miR-23b-3p overexpression, and diminished by its inhibition. In order to find the associated genes, miR-23b-3p overexpressed SK-Hep1 cells were compared with parental SK-Hep1 cells by global gene expression analysis. ANGP1, ERCC5 and G6PD genes were upregulated, while KDR, WEE1, OCLN genes were downregulated. We also detected additional two genes (AUH and MICU3) by TargetScan Release 5.2. Clinical HCC samples were divided into miR-23b-3p upregulated 48 cases (38%) and downregulated 77 cases (62%). Upregulated cases were correlated with aged patients (P=0.015), capsule invasion positive (P=0.039) and serosal invasion positive (P=0.049). Also, they showed significantly poor recurrence free survival (HR=1.64, P=0.037, 95%CI:1.03-2.59) and overall survival (HR=3.10, P=0.001, 95%:1.57-6.29) in multivariable analysis.
Conclusion: miR-23b-3p increased the HCC cell proliferation, and indicated the invasive type of HCCs. It functions as a oncogenic biomarker in HCCs and might be a therapeutic target.
Citation Format: Hiroshi Tanabe, Masamichi Hayashi, Hiroyuki Sugimoto, Keisuke Kurimoto, Sho Hirabayashi, Mitsuro Kanda, Hideki Takami, Yokiko Niwa, Naoki Iwata, Daisuke Kobayashi, Chie Tanaka, Suguru Yamada, Goro Nakayama, Masahiko Koike, Tsutomu Fujii, Michitaka Fujiwara, Yasuhiro Kodera. Oncogenic function of miR-23b-3p in hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3429. doi:10.1158/1538-7445.AM2017-3429</jats:p
[[alternative]]Molecular studies of rice (Oryza sativa L.) class III chitinases
No full text[[abstract]]Rice is one of the most important agricultural crops; biotic stresses are limiting crop productivity worldwide, hence studies aiming at identification and characterization of novel pathogen related gene(s) is gaining momentum. Chitinases belong to the pathogenesis-related protein families and play significant role in plant defense mechanism. In the present study, we identified several chitinases in rice suspension-culture, among Osm30 and Osm34 (class III) are selected for further investigations including biochemical properties, physiological functions, gene expression and regulation for future application. The phylogenetic trees of Osm30 and Osm34 with other 30 putative class III chitinases in the rice genome defines the evolutionary relationship and are classified into subclasses IIIa and IIIb respectively, indicating diverse functions in vivo. The phylogenetic analysis of Osm30 and Osm34 with other 32 putative class III chitinases in the rice genome revealed subclasses IIIa and IIIb, respectively. The expression of Osm30 and Osm34 genes was up-regulated in the presence of common rice pathogens, such as Rhizoctonia solani, Sarocladium oryzae, Gibberella fujikuroi and Bipolaris oryzae, ethylene and methyl jasmonate (MeJA), but not salicylic acid (SA). These results indicate that the expressions of these chitinases are JA/ethylene dependent and may participate in SA independent signal transduction pathway in the plant defense mechanism. Upon transfer of rice cells into fresh culture medium, Osm30 and Osm34 transcripts displayed a transient expression pattern in rice cells and subsequently reduce to basal expression level. This phenomenon may be due to mechanical agitation and osmotic change in the culture medium. In addition, rice cells secreted some inhibitory factors that regulated the Osm30 and Osm34 gene expression during culturing. It was interesting to note that ABA positively regulated the expression of Osm30 gene and inhibited Osm34. Taken together, the expression of Osm30 and Osm34 was basal level under normal culture conditions, the changes in the expression level of chitinase genes was observed after transferring into fresh culture medium. Thus rice cells sense the environmental alternation such as osmotic shock, agitation and pathogen infection probably via JA/ethylene-dependent pathway and/or other unidentified factors, to augment cellular defense mechanism.
[[alternative]]Molecular cloning the gene encoding tomato TF15 protein and characterization of its expression
No full text[[abstract]]In this study, we observed in tomato fruit the presence of a predominant 15-kDa protein, in addition to polygalacturonase and pectin methylesterase. Since the biological function of this protein is not yet known, here we named it as tomato fruit 15-kDa protein (TF15 protein).
TF15 protein can be detected in tomato fruits from various cultivars and of different developmental stages. To identify its encoding gene, we have constructed a tomato fruit cDNA library and selected from it two positive clones, HL4 and HL5, using an antiserum directed to the TF15 protein. The HL5 clone is 740 base pairs in length and contains an open reading frame encoding a polypeptide of 110 amino acids. The translated polypeptide is rich in His (19%), Glu (17%), and Lys (16%). Beside, the hydrophilic and hydrophobic amino acids within this polypeptide are present as intervened segments, suggesting the existence of an a-helix secondary structure. The result of a protein database search indicates the TF15 protein is high homologous to the ASR protein (Iusem et al., 1993).
Comparative to its levels in the root, stem, and leaves of tomato plant, TF15 protein is mainly expressed in the fruit. In the stem, however, the expression of TF15 protein may be transiently and slightly induced by PEG or ABA treatment. While Ethephon treatment lead tomato fruits of mature-green stage to ripened, the level of TF15 protein in these fruits remained unchanged. In addition, the levels of TF15 protein in both ethylene-sensitive (AVDRC CL5915-93D4-1-0-3) and ethylene-insensitive (Never ripe) tomato fruits were indistinguishable. These results indicate the expression of TF15 protein is not ethylene-stimulated. In ripening tomato fruits, the expression patterns of TF15 protein and its RNA transcript are distinct. For the former, the protein level has reached a steady state when fruits are at mature-green stage; while for the latter, the RNA level remains increasing along the ripening process. These data suggest the expression of TF15 protein and its encoding gene may be regulated at the post-transcriptinal level.
Abstract 1964: Identification of a novel molecule target for the detection, prediction, and treatment of peritoneal metastasis of gastric cancer
No full textAbstract
Background: Advanced gastric cancer (GC) frequently recurs because of undetected micrometastases even when disease is localized and patients undergo curative resection. Moreover, peritoneal metastasis is fatal. We aimed to develop novel diagnostic and therapeutic targets specific for peritoneal metastasis of GC to improve management.
Methods: We conducted a metastatic pathway-specific transcriptome analysis to identify candidate biomarkers comprising 340 patients allocated to discovery and validation sets (1:2) to evaluate the diagnostic and predictive value. The mRNA and protein levels in primary GC tissues were compared with patients’ clinical characteristics and survival. The effects of siRNA-mediated knockdown on phenotype and fluorouracil sensitivity of GC cells were evaluated in vitro, and the therapeutic effects of siRNAs were evaluated using a mouse xenograft model.
Results: Synaptotagmin VIII (SYT8) was identified as a candidate biomarker specific to peritoneal metastasis. SYT8 levels were elevated in the validation set comprising patients with peritoneal recurrence or metastasis. High SYT8 levels were significantly and specifically associated with peritoneal metastasis, and served as an independent prognostic marker for peritoneal recurrence-free survival of patients with stage II/III GC. The survival difference between high and low SYT8 levels was associated with patients who received adjuvant chemotherapy. Inhibition of SYT8 expression by GC cells correlated with decreased invasion, migration, and fluorouracil resistance. Intraperitoneal administration of SYT8-siRNA inhibited the growth of peritoneal nodules and prolonged survival of mice engrafted with GC cells.
Conclusions: SYT8 expression represents a promising diagnostic and predictive biomarker for peritoneal metastasis of GC.
Citation Format: Mitsuro Kanda, Haruyoshi Tanaka, Dai Shimizu, Daisuke Kobayashi, Chie Tanaka, Hideki Takami, Masamichi Hayashi, Naoki Iwata, Yukiko Niwa, Suguru Yamada, Tsutomu Fujii, Goro Nakayama, Hiroyuki Sugimoto, Masahiko Koike, Michitaka Fujiwara, Yasuhiro Kodera. Identification of a novel molecule target for the detection, prediction, and treatment of peritoneal metastasis of gastric cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1964. doi:10.1158/1538-7445.AM2017-1964</jats:p
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