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101.
102.
Okayasu I Mikami T Yoshida T Hana K Yokozawa M Sada M Fujiwara M Kawada N 《Histology and histopathology》2011,26(6):679-688
Cytoglobin/stellate cell activation-associated protein (Cygb/STAP), a hemoprotein, functions as part of an O2 reservoir with protective effects against oxidative stress in hepatic stellate cells. Heterogeneous expression of the neural cell adhesion molecule (NCAM)+ and/or α-smooth muscle actin (αSMA)+ has been noted in subepithelial myofibroblasts and interstitial cells of the same lineage in the colorectum. We have demonstrated that early genomic instability of both epithelial and stromal cells in ulcerative colitis (UC) is important for colorectal tumorigenesis, as well as for mucosal remodeling. To further clarify possible roles of stromal cells in mucosal remodeling and tumor development in UC, we here focused on Cygb expression of subepithelial myofibroblasts and interstitial cells, as well as αSMA and HSP47. Noncancerous mucosa of resected rectae from UC patients with or without colorectal neoplasia (14 and 20 cases, respectively) and of sporadic rectal cancer cases (16) was analyzed immunohistochemically, as well as by immuno-fluorescence and electron microscopy. The results, heterogeneous phenotypes of Cygb+, αSMA+ and HSP47+ subepithelial myofibroblasts and interstitial cells, corresponding to rectal stellate cells, were demonstrated. A decrease of Cygb+ subepithelial myofibroblasts and an increase of αSMA+ interstitial cells were significant in UC, as compared to normal rectal mucosa. Furthermore, a decrease of Cygb+ subepithelial myofibroblasts, correlating with αSMA+ and HSP47+ cells, was significant in long-standing UC with neoplasia. In conclusion, there are heterogeneous phenotypes of Cygb+, αSMA+ and HSP47+ subepithelial myofibroblasts and interstitial cells in the rectal mucosa. Mucosal remodeling with alterations of Cygb+ and/or αSMA+/HSP47+ stromal cells might have some relation to UC-associated tumorigenesis. 相似文献
103.
Head SR Komori HK Hart GT Shimashita J Schaffer L Salomon DR Ordoukhanian PT 《BioTechniques》2011,50(3):177-180
In this study, we tested the NuGEN Ovation RNA-Seq System for library preparation followed by next-generation sequencing on an Illumina GAIIx. The cDNA product of the NuGEN kit may have significant amounts of ssDNA with hairpin structures that are generated during the amplification process. These structures interfere with efficient downstream end repair, A-tailing, and adapter ligation, all standard steps in post-amplification sequencing library construction. We were able to increase the efficiency of sequencing library yields 4- to 6-fold or greater by treatment of NuGEN-amplified cDNA product with the single-strand endonuclease S1. These results suggest that this treatment effectively cleaves hairpin structures generated during amplification that are resistant to the standard enzyme cocktails used for the end-repair step. 相似文献
104.
105.
Furuta K Kubo M Sano K Demura T Fukuda H Liu YG Shibata D Kakimoto T 《Plant & cell physiology》2011,52(4):618-628
Cytokinins promote cell division and chloroplast development in tissue culture. We previously isolated two mutants of Arabidopsis thaliana, ckh1 (cytokinin-hypersensitive 1) and ckh2, which produce rapidly growing green calli in response to lower levels of cytokinins than those found in the wild type. Here we report that the product of the CKH2 gene is PICKLE, a protein resembling the CHD3 class of SWI/SNF chromatin remodeling factors. We also show that inhibition of histone deacetylase by trichostatin A (TSA) partially substituted for cytokinins, but not for auxin, in the promotion of callus growth, indicating that chromatin remodeling and histone deacetylation are intimately related to cytokinin-induced callus growth. A microarray experiment revealed that either the ckh1 mutation or the ckh2 mutation caused hypersensitivity to cytokinins in terms of gene expression, especially of photosynthesis-related genes. The ckh1 and ckh2 mutations up-regulated nuclear-encoded genes, but not plastid-encoded genes, whereas TSA deregulated both nuclear- and plastid-encoded genes. The ckh1 ckh2 double mutant showed synergistic phenotypes: the callus grew with a green color independently of exogenous cytokinins. A yeast two-hybrid experiment showed protein interaction between CKH1/EER4/AtTAF12b and CKH2/PKL. These results suggest that CKH1/EER4/AtTAF12b and CKH2/PKL may act together on cytokinin-regulated genes. 相似文献
106.
Uno Y Hosaka S Matsuno K Nakamura C Kito G Kamataki T Nagata R 《Archives of biochemistry and biophysics》2007,466(1):98-105
Cynomolgus monkey CYP2C76 does not have a corresponding ortholog in humans, and it is at least partly responsible for differences in drug metabolism between monkeys and humans. To determine if CYP2C76 is the only monkey-specific CYP gene, we identified cynomolgus monkey cDNAs for CYP2A23, CYP2A24, CYP2E1, CYP2J2, CYP3A5, CYP3A8, CYP4A11, CYP4F3, CYP4F11, CYP4F12, and CYP4F45. These CYP cDNAs showed a high sequence identity (93-96%) to the homologous human CYP cDNAs. The monkey CYPs were preferentially expressed in liver among the analyzed tissues. Moreover, all five analyzed monkey CYPs (CYP2A23, CYP2A24, CYP2E1, CYP3A5, and CYP3A8) metabolized typical substrates for human CYPs in the corresponding subfamilies. These results suggest that these 11 monkey CYP cDNAs are closely related to the human CYP cDNAs and thus, unlike CYP2C76, are not apparent monkey-specific cDNAs. 相似文献
107.
Taketeru Tomita Kiyomi Murakumo Keiichi Ueda Hiroshi Ashida Rina Furuyama 《Ethology : formerly Zeitschrift fur Tierpsychologie》2019,125(2):122-126
Underwater ultrasound, a new tool for observing the internal body parts of aquatic animals by scuba divers, allowed us long‐term and frequent observations of the embryos of captive aquatic vertebrates. New ultrasound data of captive tawny nurse sharks (Nebrius ferrugineus) revealed that their embryos frequently migrate between the right and left uteri during gestation. This report is the first reliable evidence of active embryonic locomotion in live‐bearing vertebrates and is contradictory to the concept of “sedentary embryo” which has mainly arisen from studies of mammals. The tawny nurse shark is unique among orectolobiform sharks, in which the embryo develops by feeding on sibling eggs in utero. Thus, we hypothesized that swimming aids in an efficient search and capture of these eggs in the uterine environment. 相似文献
108.
Diego Robles Mazzotti Cristiane Carvalho Singulane Vanessa Kiyomi Ota Thiago Potrich Rodrigues Tatiane Katsue Furuya Fernando José de Souza Bruna Grassiela Cordeiro Camilla Magalhães de Oliveira Amaral Elizabeth Suchi Chen Anielli Jacomini Marilia de Arruda Cardoso Smith Bianca Borsatto-Galera 《Gene》2014
Background and aims
The characterization of candidate gene polymorphisms in elderly populations is an important tool for the identification of risk factors for age-related diseases and conditions. We aimed to genotype the APOE polymorphisms (rs429358 and rs7412), rs61886492 (1561C>T) and rs202720 of GCPII gene and rs3918242 (− 1562C>T) of MMP9 gene in an older-adult/elderly cohort from Cuiabá city, Mato Grosso Brazil as well as to characterize risk factors for morbidities and conditions affecting this cohort.Methods
The studied population consisted of 570 subjects from Cuiabá city, Brazil, who were subjected to clinical interviews and blood collection for laboratory examinations and DNA extraction. Restriction Fragment Length Polymorphism Polymerase Chain Reaction (RFLP-PCR), sequence-specific primer PCR (SSP-PCR) and TaqMan® allelic discrimination assay were used for genotyping.Results
The frequencies of APOE ε2 and ε4 were 6.6% and 14.8%, respectively, and the frequencies of GCPII rs61886492 T allele, GCPII rs202720 C allele and MMP9 rs3918242 T allele were, respectively, 3.0%, 26.6% and 10.1%. Significant associations between APOE ε2 allele with lower total cholesterol and LDL-cholesterol were found. In addition, MMP9 rs3918242 T allele was associated with higher LDL-cholesterol levels, suggesting a link between lipid metabolism alteration and cardiovascular disease.Conclusions
The present findings contributed to characterize risk factors specific for the studied population and to better understand the molecular physiopathology of common morbidities and conditions affecting older-adult/elderly people. 相似文献109.
Takeshi Fukushima Hideaki Iizuka Ayaka Yokota Takehiro Suzuki Chihiro Ohno Yumiko Kono Minami Nishikiori Ayaka Seki Hideaki Ichiba Yoshinori Watanabe Seiji Hongo Mamoru Utsunomiya Masaki Nakatani Kiyomi Sadamoto Takashi Yoshio 《PloS one》2014,9(7)
The serum levels of several metabolites are significantly altered in schizophrenia patients. In this study, we performed a targeted analysis of 34 candidate metabolites in schizophrenia patients (n = 25) and compared them with those in age- and gender-matched healthy subjects (n = 27). Orthogonal partial least square-discriminant analysis revealed that complete separation between controls and patients was achieved based on these metabolites. We found that the levels of γ-glutamylcysteine (γ-GluCys), linoleic acid, arachidonic acid, D-serine, 3-hydroxybutyrate, glutathione (GSH), 5-hydroxytryptamine, threonine, and tyrosine were significantly lower, while D-lactate, tryptophan, kynurenine, and glutamate levels were significantly higher in schizophrenia patients compared to controls. Using receiver operating characteristics (ROC) curve analysis, the sensitivity, specificity, and the area under curve of γ-GluCys, a precursor of GSH, and D-lactate, a terminal metabolite of methylglyoxal, were 88.00%, 81.48%, and 0.8874, and 88.00%, 77.78%, and 0.8415, respectively. In addition, serum levels of D-lactate were negatively correlated with γ-GluCys levels in patients, but not in controls. The present results suggest that oxidative stress-induced damage may be involved in the pathogenesis of schizophrenia. 相似文献
110.
The Mutant Form of Acetolactate Synthase Genomic DNA from Rice is an Efficient Selectable Marker for Genetic Transformation 总被引:1,自引:0,他引:1
Keishi Osakabe Masaki Endo Kiyoshi Kawai Yaeko Nishizawa Kazuko Ono Kiyomi Abe Yuichi Ishikawa Hidemitsu Nakamura Hiroaki Ichikawa Shigeo Nishimura Tsutomu Shimizu Seiichi Toki 《Molecular breeding : new strategies in plant improvement》2005,16(4):313-320
The proper use of a marker gene in a transformation process is critical for the production of transgenic plants. However,
consumer concerns and regulatory requirements raise an objection to the presence of exogenous DNA in transgenic plants, especially
antibiotic-resistant genes and promoters derived from viruses. One approach to overcome this problem is the elimination of
marker genes from the plant genome by using several site-specific recombination systems. We propose an alternative method
to solve this problem using a marker gene exclusively derived from the host plant DNA. We cloned a genomic DNA fragment containing
regulatory and coding sequences of acetolactate synthase (ALS) gene from rice, and mutagenized the ALS gene into a herbicide-resistant
form. After transfer of this construct to the rice genome, transgenic plants were efficiently selected with a herbicide, bispyribac-sodium
salt, which inhibits the activity of wild type ALS. We also analyzed the regulatory feature of the rice ALS gene promoter
with the gusA reporter gene and revealed that GUS expression was observed constitutively in aerial parts of rice seedlings and root tips.
The marker system consisted exclusively of host plant DNA and enabled efficient selection in a monocot crop plant, rice. The
selection system can potentially be applied to generate transgenic plants of other crop species and can be expected to be
publicly acceptable. 相似文献