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121.
Masaaki Hashiguchi Satoshi Hachimura Akio Ametani Shuichi Kaminogawa 《Cytotechnology》2000,33(1-3):237-245
Although oral administration of a soluble proteinantigen can induce various immune responses, theeffect of the dosage of oral antigen on thepredominance of Th2-type cytokine and antibodyresponses has not been well clarified yet. In thepresent study, we fed T cell receptor (TCR) transgenic(tg) mice various amounts of chicken ovalbumin (0.1,5, and 250 mg) and examined the resulting immuneresponses to this antigen. In these TCR tg mice, theresponses of antigen-specific T cells were greatlyamplified concomitantly with significantantigen-specific cytokine secretion. We found that ahigh dose (250 mg) of antigen significantlyupregulated the serum antigen-specific IgG1 and IgAantibody responses in mice later intraperitoneallyinjected with antigen plus adjuvant. The miceadministered the same oral dose but not immunizedshowed upregulation of Th2-type IL-4 and IL-5secretion and downregulation of Th1-type IL-2 andIFN-. This enhancement of Th2-type cytokineand antibody responses was more marked when largerdoses of antigen orally administered. These resultsdemonstrated that antigen feeding induces thedevelopment of T cells secreting Th2-type cytokines ina dose-dependent manner and that these T cells have ahelper function for the production of antibodies ofthe Th2-type isotypes. This experimental system shouldbe useful to screen foods and other substances thatcan modulate Th2-type responses relating to allergy. 相似文献
122.
123.
More than a 600-fold variation in nitrogen dioxide assimilation among 217 plant taxa 总被引:4,自引:0,他引:4
H. Morikawa A. Higaki M. Nohno M. Takahashi M. Kamada M. Nakata G. Toyohara Y. Okamura K. Matsui S. Kitani K. Fujita K. Irifune & N. Goshima 《Plant, cell & environment》1998,21(2):180-190
Assimilation of nitrogen dioxide in response to fumigation with 15 N-labelled nitrogen dioxide was studied in 217 plant taxa. The taxa included 50 wild herbaceous plants collected from roadsides (42 genera, 15 families), 60 cultivated herbaceous plants (55 genera, 30 families) and 107 cultivated woody plants (74 genera, 45 families). Two parameters, the 'NO2 -N content', or NO2 -derived reduced nitrogen content in fumigated plant leaves (mg N g–1 dry weight), and the 'NO2 -utilization index', or percentage of the NO2 -derived reduced nitrogen in the total reduced nitrogen, were determined. The NO2 -N content differed 657-fold between the highest ( Eucalyptus viminalis ; 6·57) and lowest ( Tillandsia ionantha and T. caput-medusae ; 0·01) values in the 217 taxa; 62-fold in a family (Theaceae) and 26-fold in a species ( Solidago altissima ). Nine species had NO2 -utilization indices greater than 10%, of which Magnolia kobus , Eucalyptus viminalis , Populus nigra , Nicotiana tabacum and Erechtites hieracifolia had NO2 -N contents > 4·9. These plants can be considered 'NO2 -philic' because in them NO2 -nitrogen has an important function(s). The Compositae and Myrtaceae had high values for both parameters, whereas the monocots and gymnosperms had low ones. These findings suggest that the metabolic pathway of NO2 -nitrogen differs among plant species. The information presented here will be useful for creating a novel vegetation technology to reduce the atmospheric concentration of nitrogen dioxide. 相似文献
124.
Yoshinori Hiyama Tsuyoshi Asai Osamu Wada Hideto Maruno Shingo Nitta Kiyonori Mizuno Yasunobu Iwasaki Shuichi Okada 《PloS one》2015,10(1)
This study aimed to determine gait ability at hospital discharge in patients undergoing total knee arthroplasty (TKA) as an indicator of the risk of falling. Fifty-seven patients undergoing primary TKA for knee osteoarthritis participated in this study. Gait variability measured with accelerometers and physical function including knee range of motion (ROM), quadriceps strength, walking speed, and the Timed Up and Go (TUG) test were evaluated preoperatively and at discharge from the hospital (1 month before and 5 days after surgery). All patients were discharged directly home at 5 days after surgery. Knee flexion of ROM, quadriceps strength, walking speed, and the TUG test results were significantly worse at hospital discharge than preoperatively (p < 0.001). However, gait variability was not significantly different before and after TKA. This result indicated that patients following TKA surgery could walk at hospital discharge as stably as preoperatively regardless of the decrease in physical function, including knee ROM, quadriceps strength, and gait speed after surgery. 相似文献
125.
Takeichiro Aso Mioko Matsuo Hideyuki Kiyohara Kenichi Taguchi Fumihide Rikimaru Mototsugu Shimokawa Yuichi Segawa Yuichiro Higaki Hirohito Umeno Tadashi Nakashima Muneyuki Masuda 《PloS one》2015,10(3)
Background
At our institute, a chemoradioselection strategy has been used to select patients for organ preservation on the basis of response to an initial 30–40 Gy concurrent chemoradiotherapy (CCRT). Patients with a favorable response (i.e., chemoradioselected; CRS) have demonstrated better outcomes than those with an unfavorable response (i.e., nonchemoradioselected; N-CRS). Successful targeting of molecules that attenuate the efficacy of chmoradioselection may improve results. Thus, the aim of this study was to evaluate the association of a novel cancer stem cell (CSC) marker, CD44 variant 9 (CD44v9), with cellular refractoriness to chemoradioselection in advanced head and neck squamous cell carcinoma (HNSCC).Materials and Methods
Through a medical chart search, 102 patients with advanced HNSCC treated with chemoradioselection from 1997 to 2008 were enrolled. According to our algorithm, 30 patients were CRC following induction CCRT and 72 patients were N-CRS. Using the conventional immunohistochemical technique, biopsy specimens and surgically removed tumor specimens were immunostained with the anti-CD44v9 specific antibodies.Results
The intrinsic expression levels of CD44v9 in the biopsy specimens did not correlate with the chemoradioselection and patient survival. However, in N-CRS patients, the CD44v9-positive group demonstrated significantly (P = 0.008) worse prognosis, than the CD44v9-negative group. Multivariate analyses demonstrated that among four candidate factors (T, N, response to CCRT, and CD44v9), CD44v9 positivity (HR: 3.145, 95% CI: 1.235–8.008, P = 0.0163) was significantly correlated with the poor prognosis, along with advanced N stage (HR: 3.525, 95% CI: 1.054–9.060, P = 0.0228). Furthermore, the survival rate of the CD44v9-induced group was significantly (P = 0.04) worse than the CD44v9-non-induced group.Conclusions
CCRT-induced CD44v9-expressing CSCs appear to be a major hurdle to chemoradioselection. CD44v9-targeting seems to be a promising strategy to enhance the efficacy of chemoradioselection and consequent organ preservation and survival. 相似文献126.
Yosuke Hamamoto Hiromu Ito Moritoshi Furu Motomu Hashimoto Takao Fujii Masahiro Ishikawa Noriyuki Yamakawa Chikashi Terao Masayuki Azukizawa Takahiro Iwata Tsuneyo Mimori Shuichi Matsuda 《PloS one》2015,10(8)
Objective
To investigate clinical and radiological differences between joint destruction in the wrist and the feet in patients with RA.Methods
A cross-sectional clinical study was conducted in an RA cohort at a single institution. Clinical data included age, sex and duration of disease. Laboratory data included sero-positivity for anti-cyclic citrullinated peptide (CCP) antibody and RF. Radiological measurements included Larsen grades and the modified Sharp/van der Heijde method (SHS) for the hands/wrists and the feet. Statistical analyses were performed using the Kruskal—Wallis H-test, a dummy variable linear regression model and multivariate logistic regression analysis with 95% confidence interval and odds ratios.Results
A total of 405 patients were enrolled, and 314 patients were analysed in this study. The duration of disease in the foot-dominant group was significantly less than that in the wrist-dominant group. When patients were subdivided by duration of disease, the Larsen grade of the feet was significantly higher than that of the wrist in the first quadrant subgroup, but this was reversed with increasing duration of disease. Anti-CCP status was a significant predictive factor for joint destruction in the wrist but not in the feet, while RF status was not predictive in either the wrist or the feet.Conclusions
Joint destruction in the feet started earlier than in the wrist, but the latter progresses faster with increasing duration of disease. Anti-CCP status predicts joint destruction in the wrist better than in the feet. 相似文献127.
Shuichi Nakamura Alexander Leshansky Yukio Magariyama Keiichi Namba Seishi Kudo 《Biophysical journal》2014,106(1):47-54
Leptospira are spirochete bacteria distinguished by a short-pitch coiled body and intracellular flagella. Leptospira cells swim in liquid with an asymmetric morphology of the cell body; the anterior end has a long-pitch spiral shape (S-end) and the posterior end is hook-shaped (H-end). Although the S-end and the coiled cell body called the protoplasmic cylinder are thought to be responsible for propulsion together, most observations on the motion mechanism have remained qualitative. In this study, we analyzed the swimming speed and rotation rate of the S-end, protoplasmic cylinder, and H-end of individual Leptospira cells by one-sided dark-field microscopy. At various viscosities of media containing different concentrations of Ficoll, the rotation rate of the S-end and protoplasmic cylinder showed a clear correlation with the swimming speed, suggesting that these two helical parts play a central role in the motion of Leptospira. In contrast, the H-end rotation rate was unstable and showed much less correlation with the swimming speed. Forces produced by the rotation of the S-end and protoplasmic cylinder showed that these two helical parts contribute to propulsion at nearly equal magnitude. Torque generated by each part, also obtained from experimental motion parameters, indicated that the flagellar motor can generate torque >4000 pN nm, twice as large as that of Escherichia coli. Furthermore, the S-end torque was found to show a markedly larger fluctuation than the protoplasmic cylinder torque, suggesting that the unstable H-end rotation might be mechanically related to changes in the S-end rotation rate for torque balance of the entire cell. Variations in torque at the anterior and posterior ends of the Leptospira cell body could be transmitted from one end to the other through the cell body to coordinate the morphological transformations of the two ends for a rapid change in the swimming direction. 相似文献
128.
As it walks, the two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae) spins a trail of silk threads, that is followed by the predatory mite, Neoseiulus womersleyi Schicha (Acari: Phytoseiidae). Starved adult female N. womersleyi followed T. urticae trails laid down by five T. urticae females but did not follow a trail of one T. urticae female, suggesting that the amount of spun threads and their chemical components should correlate positively with the number
of T. urticae individuals. To examine whether chemical components of T. urticae trails are responsible for the predatory mite’s trail following, we collected separate T. urticae threads from the exuviae and eggs, and then washed the threads with methanol to separate chemical components from physical
attributes of the threads. Female N. womersleyi did not follow T. urticae trails that had been washed with methanol but contained physical residues, but they did follow the direction to which the
methanol extracts of the T. urticae trails was applied. These results suggest that the predatory mite follows chemical, not physical, attributes of T. urticae trails. 相似文献
129.
Okamoto T Yamada M Sekiya S Okuhara T Taguchi G Inatomi S Shimosaka M 《Bioscience, biotechnology, and biochemistry》2010,74(11):2327-2329
Agrobacterium tumefaciens was used to transform the vegetative dikaryotic mycelium of Flammulina velutipes using a hygromycin B resistance gene as selectable marker. The gene coding for urogen III methyltransferase (cob) was introduced into F. velutipes dikaryotic cells. The resulting transformant cells generated a bright red fluorescence, indicating that cob is promising as a reporter gene in F. velutipes. 相似文献
130.
Masaki Asada Tetsuo Obitsu Atsushi Kinoshita Yoshihiko Nakai Toshihiko Nagase Isamu Sugimoto Motoyuki Tanaka Hiroya Takizawa Ken Yoshikawa Kazutoyo Sato Masami Narita Shuichi Ohuchida Hisao Nakai Masaaki Toda 《Bioorganic & medicinal chemistry letters》2010,20(8):2639-2643
A series of novel N-acylsulfonamide analogs were synthesized and evaluated for their binding affinity and antagonist activity for the EP3 receptor subtype. Representative compounds were also evaluated for their inhibitory effect on PGE2-induced uterine contraction in pregnant rats. Among those tested, a series of N-acylbenzenesulfonamide analogs were found to be more potent than the corresponding carboxylic acid analogs in both the in vitro and in vivo evaluations. The structure activity relationships (SAR) are also discussed. 相似文献