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151.
152.
In this study, we describe 2 new species of Eimeria associated with the yellow-crowned Amazon Amazona ochrocephala. Eimeria amazonae n. sp. has bilayered, ellipsoidal, and smooth oocysts that measure 48.9 × 36.2 μm; the length/width ratio is 1.35. The micropyle and oocyst residuum are both absent, but the polar granule is present. Ovoidal sporocysts are 22.2 × 11.9 μm. Stieda and sub-Stieda bodies and sporocyst residuum are present. The 2 elongate sporozoites are curved and measure 18.1 × 3.4 μm; both have 2 refractile bodies. Eimeria ochrocephalae n. sp. has bilayered, ellipsoidal, and smooth oocysts that measure 43.8 × 27.7 μm; the length/width ratio is 1.58. The micropyle and oocyst residuum are absent, but the polar granule is present; ovoidal sporocysts are 20.6 × 10.1 μm. Stieda and sub-Stieda bodies and sporocyst residuum are present; 2 elongate and curved sporozoites are 15.8 × 3.4 μm, each of which has 2 refractile bodies. 相似文献
153.
Tenorio E Saeki T Fujita K Kitakawa M Baba T Mori H Isono K 《FEMS microbiology letters》2003,225(1):107-114
To understand the nature and function of bacterial biofilm and the process of its formation, we have performed systematic screening of a complete set of Escherichia coli genes/open reading frames (ORFs) to identify those that affect biofilm development upon over-expression. In contrast to the biofilm of strain AG1 used as a control, some of the genes/ORFs when over-expressed led to the formation of an abnormal biofilm such as thin, mat-like, filamentous or one easily detaching from various surfaces. Disruptants of selected genes were constructed in order to clarify their roles in the different stages of biofilm formation. Our results suggest that diverse metabolic pathways contribute to the development of biofilm. 相似文献
154.
Oxidation of 5-acetamido-4,8-anhydro-1,2,3,5-tetradeoxy-D-glycero-D-ido-non-1-enitol [3-C-(2-amino-2-deoxy-beta-D-glucopyranosyl)-1-propene] was studied to search for preparative routes to aminodeoxy didehydro nonulosonic acid derivatives. Since only moderate chiral induction was observed with osmium tetroxide dihydroxylation as well as with peracid epoxidation, the catalytic asymmetric dihydroxylation conditions were applied to give the stereocontrolled formation of 1,2-propanediol derivatives. The structures of these diastereoisomeric 1,2-propanediol derivatives were determined by X-ray crystallographic analyses. The formation of diastereoisomeric 1,2-propanediols also varied with the nature of 2-substituent on the aminodoexy glycosyl moiety. Thus 5-acetamido-4,8-anhydro-3,5-dideoxy-D-erythro-L-ido-nonitol [(2S)-3-C-(2-acetamido-2-deoxy-beta-D-glucopyranosyl)-1,2-propanediol] was obtained predominantly up to 70% from 3-C-(2-acetamido-2-deoxyglycosyl)-1-propene by the use of ADmixbeta reagent. The (2S)-propanediol derivative was transformed in a five-step reaction sequence to 2,3-didehydro-2,7-dideoxy-N-acetylneuraminic acid. 相似文献
155.
Yuki Doi Motoyuki Shimizu Tomoya Fujita Akira Nakamura Noboru Takizawa Naoki Takaya 《Applied and environmental microbiology》2014,80(6):1910-1918
We identified the extremely nitrite-tolerant bacterium Achromobacter denitrificans YD35 that can grow in complex medium containing 100 mM nitrite (NO2−) under aerobic conditions. Nitrite induced global proteomic changes and upregulated tricarboxylate (TCA) cycle enzymes as well as antioxidant proteins in YD35. Transposon mutagenesis generated NO2−-hypersensitive mutants of YD35 that had mutations at genes for aconitate hydratase and α-ketoglutarate dehydrogenase in the TCA cycle and a pyruvate dehydrogenase (Pdh) E1 component, indicating the importance of TCA cycle metabolism to NO2− tolerance. A mutant in which the pdh gene cluster was disrupted (Δpdh mutant) could not grow in the presence of 100 mM NO2−. Nitrite decreased the cellular NADH/NAD+ ratio and the cellular ATP level. These defects were more severe in the Δpdh mutant, indicating that Pdh contributes to upregulating cellular NADH and ATP and NO2−-tolerant growth. Exogenous acetate, which generates acetyl coenzyme A and then is metabolized by the TCA cycle, compensated for these defects caused by disruption of the pdh gene cluster and those caused by NO2−. These findings demonstrate a link between NO2− tolerance and pyruvate/acetate metabolism through the TCA cycle. The TCA cycle mechanism in YD35 enhances NADH production, and we consider that this contributes to a novel NO2−-tolerating mechanism in this strain. 相似文献
156.
Tomoya Kitani Daisuke Kami Satoaki Matoba Satoshi Gojo 《Journal of cellular and molecular medicine》2014,18(8):1694-1703
In eukaryotic cells, mitochondrial dysfunction is associated with a variety of human diseases. Delivery of exogenous functional mitochondria into damaged cells has been proposed as a mechanism of cell transplant and physiological repair for damaged tissue. We here demonstrated that isolated mitochondria can be transferred into homogeneic and xenogeneic cells by simple co‐incubation using genetically labelled mitochondria, and elucidated the mechanism and the effect of direct mitochondrial transfer. Intracellular localization of exogenous mitochondria was confirmed by PCR, real‐time PCR, live fluorescence imaging, three‐dimensional reconstruction imaging, continuous time‐lapse microscopic observation, flow cytometric analysis and immunoelectron microscopy. Isolated homogeneic mitochondria were transferred into human uterine endometrial gland‐derived mesenchymal cells in a dose‐dependent manner. Moreover, mitochondrial transfer rescued the mitochondrial respiratory function and improved the cellular viability in mitochondrial DNA‐depleted cells and these effects lasted several days. Finally, we discovered that mitochondrial internalization involves macropinocytosis. In conclusion, these data support direct transfer of exogenous mitochondria as a promising approach for the treatment of various diseases. 相似文献
157.
Complete Demonstration of the Valence Electronic Structure Inside a Practical Organic Solar Cell Probed by Low Energy Photoemission
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Yasuo Nakayama Thanh Luan Nguyen Yusuke Ozawa Shin'ichi Machida Tomoya Sato Hiroshi Tokairin Yutaka Noguchi Hisao Ishii 《Liver Transplantation》2014,4(7)
The complete electronic structure inside a practical organic photovoltaic (OPV) device consisting of a trilayer structure of copper‐phthalocyanine (CuPc), fullerene (C60), and bathocuproine (BCP) is demonstrated using low‐energy ultraviolet photoelectron spectroscopy (LE‐UPS) and photoelectron yield spectroscopy (PYS). The molecular orbital energy alignment and electrostatic potential distribution throughout the entire device is illustrated based on the LE‐UPS results. A favorable potential gradient to carry the photogenerated holes and electrons is manifested to be built spontaneously in the CuPc and BCP layers, respectively. Furthermore, the ultrahigh sensitivity measurements of LE‐UPS clearly unveil the distributions of faint density‐of‐states in the energy‐gap region in the organic films. Substantially barrierless contacts to both electrodes are fulfilled by the existence of these gap states. The electronic structure under simulated sunlight illumination is examined for the purpose of elucidating the electronic structures inside the working devices in the open‐circuit condition. These results indicate experimentally the electronic functionalities of each organic material, in particular of the BCP buffer layer, on the cell efficiency. 相似文献
158.
Mana Iizuka Yuhya Wakasa Hiroto Tsuboi Hiromitsu Asashima Tomoya Hirota Yuya Kondo Isao Matsumoto Fumio Takaiwa Takayuki Sumida 《Plant biotechnology journal》2014,12(8):1143-1152
Rheumatoid arthritis (RA) is an autoimmune disease associated with the recognition of self proteins secluded in arthritic joints. We previously reported that altered peptide ligands (APLs) of type II collagen (CII256‐271) suppress the development of collagen‐induced arthritis (CIA). In this study, we generated transgenic rice expressing CII256‐271 and APL6 contained in fusion proteins with the rice storage protein glutelin in the seed endosperm. These transgene products successfully and stably accumulated at high levels (7–24 mg/g seeds) in protein storage vacuoles (PB‐II) of mature seeds. We examined the efficacy of these transgenic rice seeds by performing oral administration of the seeds to CIA model mice that had been immunized with CII. Treatment with APL6 transgenic rice for 14 days significantly inhibited the development of arthritis (based on clinical score) and delayed disease onset during the early phase of arthritis. These effects were mediated by the induction of IL‐10 from CD4+ CD25? T cells against CII antigen in splenocytes and inguinal lymph nodes (iLNs), and treatment of APL had no effect on the production of IFN‐γ, IL‐17, IL‐2 or Foxp3+ Treg cells. These findings suggest that abnormal immune suppressive mechanisms are involved in the therapeutic effect of rice‐based oral vaccine expressing high levels of APLs of type II collagen on the autoimmune disease CIA, suggesting that the seed‐based mucosal vaccine against CIA functions via a unique mechanism. 相似文献
159.
Tomoya Hirose Shigeto Hamaguchi Naoya Matsumoto Taro Irisawa Masafumi Seki Osamu Tasaki Hideo Hosotsubo Norihisa Yamamoto Kouji Yamamoto Yukihiro Akeda Kazunori Oishi Kazunori Tomono Takeshi Shimazu 《PloS one》2014,9(11)
Neutrophil extracellular traps (NETs), a newly identified immune mechanism, are induced by inflammatory stimuli. Modification by citrullination of histone H3 is thought to be involved in the in vitro formation of NETs. The purposes of this study were to evaluate whether NETs and citrullinated histone H3 (Cit-H3) are present in the bloodstream of critically ill patients and to identify correlations with clinical and biological parameters. Blood samples were collected from intubated patients at the time of ICU admission from April to June 2011. To identify NETs, DNA and histone H3 were visualized simultaneously by immunofluorescence in blood smears. Cit-H3 was detected using a specific antibody. We assessed relationships of the presence of NETs and Cit-H3 with the existence of bacteria in tracheal aspirate, SIRS, diagnosis, WBC count, and concentrations of IL-8, TNF-α, cf-DNA, lactate, and HMGB1. Forty-nine patients were included. The median of age was 66.0 (IQR: 52.5–76.0) years. The diagnoses included trauma (7, 14.3%), infection (14, 28.6%), resuscitation from cardiopulmonary arrest (8, 16.3%), acute poisoning (4, 8.1%), heart disease (4, 8.1%), brain stroke (8, 16.3%), heat stroke (2, 4.1%), and others (2, 4.1%). We identified NETs in 5 patients and Cit-H3 in 11 patients. NETs and/or Cit-H3 were observed more frequently in “the presence of bacteria in tracheal aspirate” group (11/22, 50.0%) than in “the absence of bacteria in tracheal aspirate” group (4/27, 14.8%) (p<.01). Multiple logistic regression analysis showed that only the presence of bacteria in tracheal aspirate was significantly associated with the presence of NETs and/or Cit-H3. The presence of bacteria in tracheal aspirate may be one important factor associated with NET formation. NETs may play a pivotal role in the biological defense against the dissemination of pathogens from the respiratory tract to the bloodstream in potentially infected patients. 相似文献
160.
Zheng Wang Akira Sato Daiki Akiyama Taizo Kimura Kazuko Tajiri Tomoya Hoshi Satoshi Sakai Akira Koike Takashi Miyauchi Kazutaka Aonuma 《Life sciences》2014