ドゥルーズ思想研究 -「出来事」と「生成変化」の論理と政治-

早大学位記番号:新8303早稲田大

ジェネティック制御下にある発育鶏卵を用いた工学的in vivo 薬剤評価系の開発

The drug discovery research of clinical-use antioxidants, which may control various vascular disorders caused by the oxidative stress, is extremely important. We present the development of an in vivo evaluation system of antioxidants for their vascular protective activities using the chick embryonic chorioallantoic membrane (CAM). In the case of 12-days chick embryos, the topical administration of 2,2'-azobis(2-methylpropionamidine) dihydrochloride (AAPH) induced their vascular injuries against the CAM veins and venous capillaries but without substantial fatal damage. Artepillin C, a potent natural antioxidant, did not show the chick embryo’s venous injury, and pre-treatment with artepillin C would tend to protect the CAM veins injuries induced by the post-administration of AAPH. These results suggest that artepillin C might be able to protect the AAPH-induced vascular injury in in vivo. In conclusion, we showed the possibility of in vivo evaluation system of antioxidants for their vascular protective activities using the chick embryo

低酸素細胞特異的な蛍光イメージング剤の開発

We have designed and evaluated UTX-12 as a novel fluorescent pH probe for tumor hypoxia imaging. UTX-12 consists of a p-nitro benzyl moiety, which is a latent hypoxia-selective leaving group activated by nitro reduction, directly linked to SNARF. Although UTX-12 itself is colorless and non-fluorescent in aqueous solution, nitro reduction triggers the release of SNARF which has well-characterized long wavelength absorption and fluorescence that is sensitive to pH. The resultant SNARF, released intracellularly by enzymatic reduction of UTX-12, allows measurement of pH by pH-dependent dual emission shifts. UTX-12 showed clear differences in fluorescence behavior between hypoxic and aerobic conditions in liver microsomes and inside V79 cells. These data are confirmation that UTX-12 is biologically reduced inside tumor cells and the released SNARF should monitor intracellular pH of tumor cells selectively with reduced background signal

Multi-omic Analyses of Extensively Decayed Pinus contorta Reveal Expression of a Diverse Array of Lignocellulose-Degrading Enzymes.

Fungi play a key role cycling nutrients in forest ecosystems, but the mechanisms remain uncertain. To clarify the enzymatic processes involved in wood decomposition, the metatranscriptomics and metaproteomics of extensively decayed lodgepole pine were examined by RNA sequencing (RNA-seq) and liquid chromatography-tandem mass spectrometry (LC-MS/MS), respectively. Following de novo metatranscriptome assembly, 52,011 contigs were searched for functional domains and homology to database entries. Contigs similar to basidiomycete transcripts dominated, and many of these were most closely related to ligninolytic white rot fungi or cellulolytic brown rot fungi. A diverse array of carbohydrate-active enzymes (CAZymes) representing a total of 132 families or subfamilies were identified. Among these were 672 glycoside hydrolases, including highly expressed cellulases or hemicellulases. The CAZymes also included 162 predicted redox enzymes classified within auxiliary activity (AA) families. Eighteen of these were manganese peroxidases, which are key components of ligninolytic white rot fungi. The expression of other redox enzymes supported the working of hydroquinone reduction cycles capable of generating reactive hydroxyl radicals. These have been implicated as diffusible oxidants responsible for cellulose depolymerization by brown rot fungi. Thus, enzyme diversity and the coexistence of brown and white rot fungi suggest complex interactions of fungal species and degradative strategies during the decay of lodgepole pine.IMPORTANCE The deconstruction of recalcitrant woody substrates is a central component of carbon cycling and forest health. Laboratory investigations have contributed substantially toward understanding the mechanisms employed by model wood decay fungi, but few studies have examined the physiological processes in natural environments. Herein, we identify the functional genes present in field samples of extensively decayed lodgepole pine (Pinus contorta), a major species distributed throughout the North American Rocky Mountains. The classified transcripts and proteins revealed a diverse array of oxidative and hydrolytic enzymes involved in the degradation of lignocellulose. The evidence also strongly supports simultaneous attack by fungal species employing different enzymatic strategies

Enhancement of Secondary Cell Wall Formation in Poplar Xylem Using a Self-Reinforced System of Secondary Cell Wall-Related Transcription Factors

The secondary cell wall (SCW) in the xylem is one of the largest sink organs of carbon in woody plants, and is considered a promising sustainable bioresource for biofuels and biomaterials. To enhance SCW formation in poplar (Populus sp.) xylem, we developed a self-reinforced system of SCW-related transcription factors from Arabidopsis thaliana, involving VASCULAR-RELATED NAC-DOMAIN7 (VND7), SECONDARY WALL-ASSOCIATED NAC-DOMAIN PROTEIN 1/NAC SECONDARY WALL THICKENING-PROMOTING FACTOR3 (SND1/NST3), and MYB46. In this system, these transcription factors were fused with the transactivation domain VP16 and expressed under the control of the Populus trichocarpa CesA18 (PtCesA18) gene promoter, creating the chimeric genes PtCesA18pro::AtVND7:VP16, PtCesA18pro::AtSND1:VP16, and PtCesA18pro::AtMYB46:VP16. The PtCesA18 promoter is active in tissues generating SCWs, and can be regulated by AtVND7, AtSND1, and AtMYB46; thus, the expression levels of PtCesA18pro::AtVND7:VP16, PtCesA18pro::AtSND1:VP16, and PtCesA18pro::AtMYB46:VP16 are expected to be boosted in SCW-generating tissues. In the transgenic hybrid aspens (Populus tremula x tremuloides T89) expressing PtCesA18pro::AtSND1:VP16 or PtCesA18pro::AtMYB46:VP16 grown in sterile half-strength Murashige and Skoog growth medium, SCW thickening was significantly enhanced in the secondary xylem cells, while the PtCesA18pro::AtVND7:VP16 plants showed stunted xylem formation, possibly because of the enhanced programmed cell death (PCD) in the xylem regions. After acclimation, the transgenic plants were transferred from the sterile growth medium to pots of soil in the greenhouse, where only the PtCesA18pro::AtMYB46:VP16 aspens survived. A nuclear magnetic resonance footprinting cell wall analysis and enzymatic saccharification analysis demonstrated that PtCesA18pro::AtMYB46:VP16 influences cell wall properties such as the ratio of syringyl (S) and guaiacyl (G) units of lignin, the abundance of the lignin beta-aryl ether and resinol bonds, and hemicellulose acetylation levels. Together, these data indicate that we have created a self-reinforced system using SCW-related transcription factors to enhance SCW accumulation

イソプレン ソクサ オ ユウスル ショクブツ セイブン ノ ex vivo ユウキ ゴウセイ ト ソノ セイリ カッセイ ノ ヒョウカ

Phytyl quinols, namely acyclic tocopherols, are key intermediates of tocopherol biosynthesis, but their biological activities remain unclear. We therefore investigated the structure-activity relationship of phytyl quinols to apply a chemical biosynthesis design for an antiatherosclerosis drug based on isoprenomics. We have achieved the biosynthesis-oriented synthesis of α- and β-phytyl quinol as an unnatural intermediate, other γ- and δ-phytyl quinol as a natural one. All four phytyl quinols showed almost the same moderate inhibitory activity against low-density lipoprotein oxidation instead of their different degree of C-methylation with character different from tocopherols. In vivo toxicities of phytyl quinols against chick embryo chorioallantoic membrane vasculature were hardly observed. We proposed phytyl quinols were possible antioxidants in plants and animals, like vitamin E

イソプレン ソクサ オ ユウスル ショクブツ セイブン ノ ex vivo ユウキ ゴウセイ ト ソノ セイリ カッセイ ノ ヒョウカ

Phytyl quinols, namely acyclic tocopherols, are key intermediates of tocopherol biosynthesis, but their biological activities remain unclear. We therefore investigated the structure-activity relationship of phytyl quinols to apply a chemical biosynthesis design for an antiatherosclerosis drug based on isoprenomics. We have achieved the biosynthesis-oriented synthesis of α- and β-phytyl quinol as an unnatural intermediate, other γ- and δ-phytyl quinol as a natural one. All four phytyl quinols showed almost the same moderate inhibitory activity against low-density lipoprotein oxidation instead of their different degree of C-methylation with character different from tocopherols. In vivo toxicities of phytyl quinols against chick embryo chorioallantoic membrane vasculature were hardly observed. We proposed phytyl quinols were possible antioxidants in plants and animals, like vitamin E

Endoscopic resection is a suitable initial treatment strategy for oxyntic gland adenoma or gastric adenocarcinoma of the fundic gland type

The aim of this study was to reveal the histological features of oxyntic gland adenomas and gastric adenocarcinoma of the fundic-gland type (GA-FG). We retrospectively examined the histological features of 126 lesions of oxyntic gland adenoma and/or GA-FG in 116 patients. The prevalence of oxyntic gland adenomas and GA-FG was approximately equal. The majority of the lesions were resected by endoscopic mucosal resection using a diathermic snare (EMR, n=42) or endoscopic submucosal dissection (ESD, n=72). Histologically, there were no lesions with invasion at the level of the muscularis propria or deeper, and lymphovascular invasion was present in 1.6%. Of the ESD and EMR specimens, there were no lesions that were positive for vertical margins. Among the eight GA-FG patients with deep (>= 500 mu m) submucosal invasion, six were treated with endoscopic resection alone, and no recurrence was documented. No patients died of the disease during the median follow-up period of 14.5 months. In conclusion, all lesions were confined to the mucosa or submucosa and were negative for vertical margins. Lymphovascular invasion was present in only 1.6% of the patients. Thus, we believe that endoscopic resection is a suitable initial treatment method for oxyntic gland adenoma and GA-FG

Genomes of Neutrophilic Sulfur-Oxidizing Chemolithoautotrophs Representing 9 Proteobacterial Species From 8 Genera

Even in the current era of metagenomics, the interpretation of nucleotide sequence data is primarily dependent on knowledge obtained from a limited number of microbes isolated in pure culture. Thus, it is of fundamental importance to expand the variety of strains available in pure culture, to make reliable connections between physiological characteristics and genomic information. In this study, two sulfur oxidizers that potentially represent two novel species were isolated and characterized. They were subjected to whole-genome sequencing together with 7 neutrophilic and chemolithoautotrophic sulfur-oxidizing bacteria. The genes for sulfur oxidation in the obtained genomes were identified and compared with those of isolated sulfur oxidizers in the classes Betaproteobacteria and Gammaproteobacteria. Although the combinations of these genes in the respective genomes are diverse, typical combinations corresponding to three types of core sulfur oxidation pathways were identified. Each pathway involves one of three specific sets of proteins, SoxCD, DsrABEFHCMKJOP, and HdrCBAHypHdrCB. All three core pathways contain the SoxXYZAB proteins, and a cytoplasmic sulfite oxidase encoded by soeABC is a conserved component in the core pathways lacking SoxCD. Phylogenetically close organisms share same core sulfur oxidation pathway, but a notable exception was observed in the family ‘Sulfuricellaceae’. In this family, some strains have either core pathway involving DsrABEFHCMKJOP or HdrCBAHypHdrCB, while others have both pathways. A proteomics analysis showed that proteins constituting the core pathways were produced at high levels. While hypothesized function of HdrCBAHypHdrCB is similar to that of Dsr system, both sets of proteins were detected with high relative abundances in the proteome of a strain possessing genes for these proteins. In addition to the genes for sulfur oxidation, those for arsenic metabolism were searched for in the sequenced genomes. As a result, two strains belonging to the families Thiobacillaceae and Sterolibacteriaceae were observed to harbor genes encoding ArxAB, a type of arsenite oxidase that has been identified in a limited number of bacteria. These findings were made with the newly obtained genomes, including those from 6 genera from which no genome sequence of an isolated organism was previously available. These genomes will serve as valuable references to interpret nucleotide sequences