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131.
Taoka H Yamamoto Y Sakurai N Fukuda M Asakawa Y Kurasaki A Oharaseki T Kubushiro K 《Human cell》2010,23(4):126-133
We compared the detection rate of cervical neoplasias between a liquid-based cytology (LBC) method using SurePath and the conventional method. We also studied the feasibility of human papillomavirus (HPV) typing by linear array assay. Cytological specimens from 1551 Japanese women were prepared using the conventional and SurePath methods; the cytological and histological results from biopsy samples were compared. HPV typing using an HPV linear array assay was carried out on residual specimens using the SurePath method. The cytodiagnostic results showed a concordance rate of 85.3% (Κ= 0.46) between the two methods. The sensitivity of lesions histopathologically diagnosed as CIN1 or above was not significantly different between the two methods (P = 0.575-1.000). The receiver operating characteristic curve analysis of the detectability in CIN2 or above revealed no significant difference between the two methods (P = 0.096). Among the 44 patients who underwent HPV typing using a linear array assay, 33 samples were eligible for HPV testing and were stored at ambient temperature. In conclusion, the SurePath and conventional methods have equivalent abilities for detecting cervical lesions. After preparation for cytological diagnosis, use of the remaining cells from the SurePath specimens to perform HPV typing using the linear array method could be feasible. 相似文献
132.
Toshiaki Hattori Nobuhiro Anraku Ryo Kato 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(3-4):477-480
Five chitosan oligosaccharides were separated in acidic aqueous solution by capillary electrophoresis (CE) with indirect photometric detection using a positively coated capillary. Electrophoretic mobility of the chitooligosaccharides (COSs) depended on the number of monomer units in acidic aqueous solution, similar to other polyelectrolyte oligomers. The separation was developed in nitric acid aqueous solution at pH 3.0 with 1 mM Crystal Violet, using a capillary positively coated with N-trimethoxypropyl-N,N,N-trimethylammonium chloride. The limit of the detection for chitooligosaccharides with two to six saccharide chains was less than 5 μM. CE determination of an enzymatically hydrolyzed COS agreed with results from HPLC. 相似文献
133.
Hisashi Kato-Noguchi Madoka Yamamoto Kazuya Tamura Toshiaki Teruya Kiyotake Suenaga Yoshiharu Fujii 《Plant Growth Regulation》2010,60(2):127-131
Aqueous methanol extracts of rattail fescue (Vulpia myuros) inhibited the growth of roots and shoots of cress (Lepidium sativum), lettuce (Lactuca sativa), alfalfa (Medicago sativa), timothy (Phleum pratense), Digitaria sanguinalis and Lolium multiflorum. Increasing the extract concentration increased the inhibition, suggesting that rattail fescue may have growth inhibitory
substances and possess allelopathic potential. The aqueous methanol extract of rattail fescue was purified and two main inhibitory
substances were isolated and identified by spectral data as (−)-3-hydroxy-β-ionone and (+)-3-oxo-α-ionol. Both substances
inhibited root and shoot growth of cress at concentrations greater than 0.3 μM. The concentrations required for 50% growth
inhibition on root and shoot growth of cress, lettuce, alfalfa, timothy, D. sanguinalis and L. multiflorum were 2.7–19.7 μM for (−)-3-hydroxy-β-ionone, and 2.1–34.5 μM for (+)-3-oxo-α-ionol. The concentration of (−)-3-hydroxy-β-ionone
and (+)-3-oxo-α-ionol, respectively, in rattail fescue was 7.8 and 3.7 μg g−1 fresh weight. Considering the endogenous level and the inhibitory activity, (−)-3-hydroxy-β-ionone and (+)-3-oxo-α-ionol
may work as allelopathic substances in rattail fescue through the growth inhibition of neighboring plant species. 相似文献
134.
Kyung-Duk Min Yulin Liao Hidetoshi Okazaki Kazunori Fujimoto Ayako Takahashi Satoru Yamazaki Shoji Sanada Atsushi Nakano Toshiaki Otsuka Tadashi Isomura Naoki Mochizuki 《Biochemical and biophysical research communications》2010,393(1):55-7396
Although various management methods have been developed for heart failure, it is necessary to investigate the diagnostic or therapeutic targets of heart failure. Accordingly, we have developed different approaches for managing heart failure by using conventional microarray analyses. We analyzed gene expression profiles of myocardial samples from 12 patients with heart failure and constructed datasets of heart failure-associated genes using clinical parameters such as pulmonary artery pressure (PAP) and ejection fraction (EF). From these 12 genes, we selected four genes with high expression levels in the heart, and examined their novelty by performing a literature-based search. In addition, we included four G-protein-coupled receptor (GPCR)-encoding genes, three enzyme-encoding genes, and one ion-channel protein-encoding gene to identify a drug target for heart failure using in silico microarray database. After the in vitro functional screening using adenovirus transfections of 12 genes into rat cardiomyocytes, we generated gene-targeting mice of five candidate genes, namely, MYLK3, GPR37L1, GPR35, MMP23, and NBC1. The results revealed that systolic blood pressure differed significantly between GPR35-KO and GPR35-WT mice as well as between GPR37L1-Tg and GPR37L1-KO mice. Further, the heart weight/body weight ratio between MYLK3-Tg and MYLK3-WT mice and between GPR37L1-Tg and GPR37L1-KO mice differed significantly. Hence, microarray analysis combined with clinical parameters can be an effective method to identify novel therapeutic targets for the prevention or management of heart failure. 相似文献
135.
Kubo M Kobayashi K Masegi T Sakai H Tsubota T Asano M Itani M Yanai T 《Journal of wildlife diseases》2007,43(3):542-544
A free-flying Great Egret (Ardea alba) captured in Gifu, central Japan, in May 2006 had a large mass on the right carpal joint. The tumor was diagnosed as chondrosarcoma by histopathologic examination. 相似文献
136.
Multiphysics simulation of blood flow and LDL transport in a porohyperelastic arterial wall model 总被引:1,自引:0,他引:1
Atherosclerosis localizes at a bend andor bifurcation of an artery, and low density lipoproteins (LDL) accumulate in the intima. Hemodynamic factors are known to affect this localization and LDL accumulation, but the details of the process remain unknown. It is thought that the LDL concentration will be affected by the filtration flow, and that the velocity of this flow will be affected by deformation of the arterial wall. Thus, a coupled model of a blood flow and a deformable arterial wall with filtration flow would be invaluable for simulation of the flow field and concentration field in sequence. However, this type of highly coupled interaction analysis has not yet been attempted. Therefore, we performed a coupled analysis of an artery with multiple bends in sequence. First, based on the theory of porous media, we modeled a deformable arterial wall using a porohyperelastic model (PHEM) that was able to express both the filtration flow and the viscoelastic behavior of the living tissue, and simulated a blood flow field in the arterial lumen, a filtration flow field and a displacement field in the arterial wall using a fluid-structure interaction (FSI) program code by the finite element method (FEM). Next, based on the obtained results, we further simulated LDL transport using a mass transfer analysis code by the FEM. We analyzed the PHEM in comparison with a rigid model. For the blood flow, stagnation was observed downward of the bends. The direction of the filtration flow was only from the lumen to the wall for the rigid model, while filtration flows from both the wall to the lumen and the lumen to the wall were observed for the PHEM. The LDL concentration was high at the lumenwall interface for both the PHEM and rigid model, and reached its maximum value at the stagnation area. For the PHEM, the maximum LDL concentration in the wall in the radial direction was observed at the position of 3% wall thickness from the lumenwall interface, while for the rigid model, it was observed just at the lumenwall interface. In addition, the peak LDL accumulation area of the PHEM moved about according to the pulsatile flow. These results demonstrate that the blood flow, arterial wall deformation, and filtration flow all affect the LDL concentration, and that LDL accumulation is due to stagnation and the presence of filtration flow. Thus, FSI analysis is indispensable. 相似文献
137.
Todaka N Moriya S Saita K Hondo T Kiuchi I Takasu H Ohkuma M Piero C Hayashizaki Y Kudo T 《FEMS microbiology ecology》2007,59(3):592-599
To clarify the lignocellulolytic process of the lower termite symbiotic protistan system, we constructed a cDNA library from an as yet uncultivated symbiotic protist community of the lower termite Reticulitermes speratus. The library was constructed by the biotinylated CAP trapper method and analyzed by one-pass sequencing. Phylogenetic analysis of actin orthologs confirmed that the resulting library reflected the intact organismal and mRNA composition of the symbiotic system. The contents of the library included abundant numbers of lignocellulolytic genes of the glycosyl hydrolase family orthologs (families 3, 5, 7, 8, 10, 11, 26, 43, 45 and 62). Our results clearly indicated that a multiple family of glycosyl hydrolase enzymes was involved in the protistan cellulose degradation system. The data also suggested that the most extensively expressed enzyme was glycosyl hydrolase family 7, a cellobiohydrolase ortholog. This family of enzymes enables the degradation of crystalline cellulose, the principal component of wood biomass. 相似文献
138.
Takezawa T Takeuchi T Nitani A Takayama Y Kino-Oka M Taya M Enosawa S 《Journal of biotechnology》2007,131(1):76-83
We previously succeeded in converting a soft and turbid disk of type-I collagen gel into a strong and transparent vitrigel membrane utilizing a concept for the vitrification of heat-denatured proteins and have demonstrated its protein-permeability and advantage as a scaffold for reconstructing crosstalk models between two different cell types. In this study, we observed the nano-structure of the type-I collagen vitrigel membrane and verified its utility for paracrine assays in vitro and drug delivery systems in vivo. Scanning electron microscopic observation revealed that the vitrigel membrane was a dense network architecture of typical type-I collagen fibrils. In the crosstalk model between PC-12 pheochromocytoma cells and L929 fibroblasts, nerve growth factor (NGF) secreted from L929 cells passed through the collagen vitrigel membrane and induced the neurite outgrowth of PC-12 cells by its paracrine effect. Also, the collagen vitrigel membrane containing vascular endothelial growth factor (VEGF) showed sustained-release of VEGF in vitro and its subcutaneous transplantation into a rat resulted in remarkable angiogenesis. These data suggest that the collagen vitrigel membrane is useful for paracrine assays in vitro and drug delivery systems in vivo. 相似文献
139.
CD200 expression on tumor cells suppresses antitumor immunity: new approaches to cancer immunotherapy 总被引:1,自引:0,他引:1
Kretz-Rommel A Qin F Dakappagari N Ravey EP McWhirter J Oltean D Frederickson S Maruyama T Wild MA Nolan MJ Wu D Springhorn J Bowdish KS 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(9):5595-5605
Although the immune system is capable of mounting a response against many cancers, that response is insufficient for tumor eradication in most patients due to factors in the tumor microenvironment that defeat tumor immunity. We previously identified the immune-suppressive molecule CD200 as up-regulated on primary B cell chronic lymphocytic leukemia (B-CLL) cells and demonstrated negative immune regulation by B-CLL and other tumor cells overexpressing CD200 in vitro. In this study we developed a novel animal model that incorporates human immune cells and human tumor cells to address the effects of CD200 overexpression on tumor cells in vivo and to assess the effect of targeting Abs in the presence of human immune cells. Although human mononuclear cells prevented tumor growth when tumor cells did not express CD200, tumor-expressed CD200 inhibited the ability of lymphocytes to eradicate tumor cells. Anti-CD200 Ab administration to mice bearing CD200-expressing tumors resulted in nearly complete tumor growth inhibition even in the context of established receptor-ligand interactions. Evaluation of an anti-CD200 Ab with abrogated effector function provided evidence that blocking of the receptor-ligand interaction was sufficient for control of CD200-mediated immune modulation and tumor growth inhibition in this model. Our data indicate that CD200 expression by tumor cells suppresses antitumor responses and suggest that anti-CD200 treatment might be therapeutically beneficial for treating CD200-expressing cancers. 相似文献
140.
Yoshida M Nishikawa Y Omori Y Yoshioka T Tokairin T McCourt P Enomoto K 《Cell and tissue research》2007,329(2):273-282
Embryonic development of the liver is closely associated with vascular organization. However, little is known about the mechanisms
of vascular differentiation during liver development. Our previous study showed that the maturation of sinusoidal endothelial
cells (SECs) occurred during embryonic day 13.0 (E13.0) to E15.0. To improve our understanding of SEC differentiation, we
examined here the expression of maturation markers, SE-1 and stabilin-2, in fetal livers and also attempted to establish an
in vitro SEC differentiation system by culturing E13.5 fetal liver cells. Immunohistochemical examination of SE-1 and stabilin-2
expression during fetal rat liver development revealed that these differentiation markers were co-expressed in SECs in the
late stage of liver development, although stabilin-2 was expressed in almost all vascular endothelial cells in the early stage.
Liver cells from the E13.5 rat fetus were cultured in EBM-2 medium containing vascular endothelial growth factor (VEGF), transforming
growth factor β1 (TGF-β1) and VEGF plus SB-431542 (an inhibitor of the TGF-β1 receptor, activin receptor-like kinase 5 [ALK-5]).
In vitro SEC differentiation, as indicated by the appearance of cells co-expressing SE-1 and stabilin-2 and of cells with
cytoplasmic fenestrae in endothelial sheets, was induced by the addition of both VEGF and SB-431542, an inhibitor of the phosphorylation
of Smad2/3 but not that of Smad1/5/8 in the cultured cells. These results indicate for the first time that both VEGF signaling
and the blocking of the ALK-5-Smad2/3 signal pathway are important for the fetal differentiation of SECs. 相似文献