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491.
The expression of differentiation by chicken lens epithelium in in vitro cell culture 总被引:7,自引:2,他引:5
Dissociated cells of the lens epithelium of newly hatched chickens were cultured in vitro to investigate whether cells actively grown in culture retain their own differentive entiative traits to form lens fibers. After an exponential growth phase of the flattened epithelial cells, a number of “islets” of smaller epithelial cells with polygonal shape appeared. Along the periphery of these islets, the characteristic morphological change which leads to the formation of spherical bodies was observed. Electron microscopic observation showed the differentiation of lens fibers in these spherical bodies comparable to those in the lens in situ. Accumulation of δ-chrystallin was confirmed in such “lentoid” bodies. Outgrowth of the lens epithelial cells was maintained in in vitro culture up to about 50 days with several subculturings. The formation of lentoid bodies occurred in each subculture generation, which started from a homogeneous population of flattened epithelial cells. The present culture conditions permit the maintenance of such a population of cells that have a high growth potential and stably retains their differentiative trait to form lens fiber, even after repeated replication under in vitro conditions. 相似文献
492.
Swarmistha Devi Aribam Tomoyuki Harada Marta Elsheimer-Matulova Taketoshi Iwata Katsushi Kanehira Hirokazu Hikono Hidenori Matsui Yohsuke Ogawa Yoshihiro Shimoji Masahiro Eguchi 《PloS one》2016,11(3)
Salmonella-specific antibodies play an important role in host immunity; however, the mechanisms of Salmonella clearance by pathogen-specific antibodies remain to be completely elucidated since previous studies on antibody-mediated protection have yielded inconsistent results. These inconsistencies are at least partially attributable to the use of polyclonal antibodies against Salmonella antigens. Here, we developed a new monoclonal antibody (mAb)-449 and identified its related immunogen that protected BALB/c mice from infection with Salmonella enterica serovar Typhimurium. In addition, these data indicate that the mAb-449 immunogen is likely a major protective antigen. Using in vitro infection studies, we also analyzed the mechanism by which mAb-449 conferred host protection. Notably, macrophages infected with mAb-449-treated S. Typhimurium showed enhanced pathogen uptake compared to counterparts infected with control IgG-treated bacteria. Moreover, these macrophages produced elevated levels of pro-inflammatory cytokine TNFα and nitric oxide, indicating that mAb-449 enhanced macrophage activation. Finally, the number of intracellular bacteria in mAb-449-activated macrophages decreased considerably, while the opposite was found in IgG-treated controls. Based on these findings, we suggest that, although S. Typhimurium has the potential to survive and replicate within macrophages, host production of a specific antibody can effectively mediate macrophage activation for clearance of intracellular bacteria. 相似文献
493.
Eri Eguchi Narumi Funakubo Kiyohide Tomooka Tetsuya Ohira Keiki Ogino Takeshi Tanigawa 《PloS one》2016,11(3)
Objectives
The aim of this study was to investigate the effects of aroma foot massage on blood pressure, anxiety, and health-related quality of life (QOL) in Japanese community-dwelling men and women using a crossover randomized controlled trial.Methods
Fifty-seven eligible participants (5 men and 52 women) aged 27 to 72 were randomly divided into 2 intervention groups (group A: n = 29; group B: n = 28) to participate in aroma foot massages 12 times during the 4-week intervention period. Systolic and diastolic blood pressure (SBP and DBP, respectively), heart rate, state anxiety, and health-related QOL were measured at the baseline, 4-week follow-up, and 8-week follow-up. The effects of the aroma foot massage intervention on these factors and the proportion of participants with anxiety were analyzed using a linear mixed-effect model for a crossover design adjusted for participant and period effects. Furthermore, the relationship between the changes in SBP and state anxiety among participants with relieved anxiety was assessed using a linear regression model.Results
Aroma foot massage significantly decreased the mean SBP (p = 0.02), DBP (p = 0.006), and state anxiety (p = 0.003) as well as the proportion of participants with anxiety (p = 0.003). Although it was not statistically significant (p = 0.088), aroma foot massage also increased the score of mental health-related QOL. The change in SBP had a significant and positive correlation with the change in state anxiety (p = 0.01) among participants with relieved anxiety.Conclusion
The self-administered aroma foot massage intervention significantly decreased the mean SBP and DBP as well as the state anxiety score, and tended to increase the mental health-related QOL scores. The results suggest that aroma foot massage may be an easy and effective way to improve mental health and blood pressure.Trial Registration
University Hospital Medical Information Network 000014260 相似文献494.
495.
Mizuno N Mochii M Yamamoto TS Takahashi TC Eguchi G Okada TS 《Differentiation; research in biological diversity》1999,65(3):141-149
Lens regeneration from non-lens ocular tissues has been well documented in amphibians, from the dorsal iris in the newt and from the outer cornea in Xenopus. To understand the early molecular events which govern lens regeneration, we examined the expression of two early marker genes of normal lens development, Pax-6 and Prox 1. In both Cynops (newt) iris and Xenopus cornea, Pax-6 is expressed soon after lentectomy in a region broader than that giving rise to the regenerating lens, indicative of an important role for Pax-6 in determination of the regeneration potential. Then Prox 1 expression begins within the Pax-6-expressing tissue, and these Prox 1-expressing cells give rise to the regenerating lens. This sequence of events also takes place in the lens placode of the embryo, indicating that the presence of the same genetic program operates in both embryonic lens development and lens regeneration, at least partly. In the Cynops iris, Pax-6 expression occurs initially in the entire marginal region of the iris after lentectomy but then becomes restricted to the dorsal region. Further studies are expected to elucidate the mechanism of this long-standing problem of the dorsal-restriction of lens regeneration from the newt iris. 相似文献
496.
Okamoto K Tanaka H Ogawa H Makino Y Eguchi H Hayashi S Yoshikawa N Poellinger L Umesono K Makino I 《The Journal of biological chemistry》1999,274(15):10363-10371
497.
Leukocyte differential analysis was performed in various species, particularly laboratory animals, by the laser multi-angle polarized light scattering separation method. Venous blood specimens were drawn from the following subjects: healthy adult men and women ("humans"); cynomolgus monkeys ("monkeys"); common marmosets ("marmosets"); beagle dogs ("dogs"); miniature potbelly pigs ("swine"); Japanese white rabbits ("rabbits"); Hartley guinea pigs ("guinea pigs"); and Sprague-Dawley rats ("rats"). 90 degrees/10 degrees scatter plot: Basophils and mononuclear-polymorphonuclear cells were separated in all subjects, but individual 10 degrees and 90 degrees scatter plots overlapped in dogs and guinea pigs, respectively. 90 degrees depolarized /90 degrees scatter plot: Neutrophils and eosinophils were clearly separated in human, monkey, guinea pig, swine and rat subjects. The eosinophil cluster was not clearly plotted in marmoset, dog, or rabbit. 0 degree/10 degrees scatter plot: Regarding this plot for monocytes and lymphocytes, cells were plotted in the following order in all subjects: lymphocytes < basophils < or = monocytes in the 0 degree (size) scatter; and lymphocytes [symbol: see text] monocytes < or = basophils in the 10 degrees (complexity) scatter. Compared to other species, the rat scatter showed a tendency to overlapping plots in both the 0 degree and 10 degrees scatters in the monocyte and lymphocyte clusters. In both dog and guinea pig, the monocyte and neutrophil plots overlapped in the 0 degree and 10 degrees scatters. Basobox: In the human and rabbit subjects, the basophil cluster was plotted within the established basobox, but no clear cell cluster was plotted in the other subjects. As a result of comparing the percentage values for leukocytes in various species obtained by using the CD3500 apparatus versus the corresponding values obtained manually, good correspondence was found in the monkey, and eosinophils in the marmoset were lower with CD3500 than manually. In the rabbit, the mean measured value for basophils matched in the manual and CD3500 findings. In the guinea pig, the CD3500 values were lower than the manual values for lymphocytes, but higher for monocytes and neutrophils. The above findings suggest that the laser multi-angle polarized light scattering separation method is indeed capable of analyzing leukocytes from various species based on cell size and cell complexity, i.e., the presence or absence of nuclei, granules and cell enclosures. 相似文献
498.
Yamasaki S Yagishita N Sasaki T Nakazawa M Kato Y Yamadera T Bae E Toriyama S Ikeda R Zhang L Fujitani K Yoo E Tsuchimochi K Ohta T Araya N Fujita H Aratani S Eguchi K Komiya S Maruyama I Higashi N Sato M Senoo H Ochi T Yokoyama S Amano T Kim J Gay S Fukamizu A Nishioka K Tanaka K Nakajima T 《The EMBO journal》2007,26(1):113-122
499.
Here we report the characterization of the type-1 isopentenyl diphosphate isomerase derived from Halobacterium sp. NRC-1. The expressed purified enzyme showed maximum isomerase activity in the presence of 1 M NaCl at 37 degrees C at pH 6.0. This type-1 enzyme appears to be the first for which the Co2+ ion is required for activity. 相似文献
500.