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61.
Introduction: We investigated whether adding ultrafine (nano-scale) oxygen-carrying bubbles to water concurrently with dissolved carbon-dioxide (CO2) could result in safe, long-duration anesthesia for fish. Results: To confirm the lethal effects of CO2 alone, fishes were anesthetized with dissolved CO2 in 20°C seawater. Within 30 minutes, all fishes, regardless of species, died suddenly due to CO2-induced narcosis, even when the water was saturated with oxygen. Death was attributed to respiration failure caused by hypoxemia. When ultrafine oxygen-carrying bubbles were supplied along with dissolved CO2, five chicken grunts were able to remain anesthetized for 22 hours and awoke normally within 2–3 hours after cessation of anesthesia. Conclusions: The high internal pressures and oxygen levels of the ultrafine bubbles enabled efficient oxygen diffusion across the branchia and permitted the organismal oxygen demands of individual anesthetized fish to be met. Thus, we demonstrated a method for safe, long-duration carbon dioxide anesthesia in living fish under normal water temperatures. 相似文献
62.
Takayuki Kishi Hiroki Kawana Misa Sayama Kumiko Makide Asuka Inoue Yuko Otani Tomohiko Ohwada Junken Aoki 《Biochemistry and Biophysics Reports》2016
Upon various stimulations, mast cells (MCs) release a wide variety of chemical mediators stored in their cytoplasmic granules, which then initiates subsequent allergic reactions. Lysophosphatidylserine (LysoPS), a kind of lysophospholipid, potentiates the histamine release from MCs triggered by antigen stimulation. We previously showed through structure-activity studies of LysoPS analogs that LysoPS with a methyl group at the carbon of the serine residue, i.e., lysophosphatidylthreonine (LysoPT), is extremely potent in stimulating the MC degranulation. In this study, as our continuing study to identify more potent LysoPS analogs, we developed LysoPS analogs with fatty acid surrogates. We found that the substitution of oleic acid to an aromatic fatty acid surrogate (C3-pH-p-O-C11) in 2-deoxy-1-LysoPS resulted in significant increase in the ability to induce MCs degranulation compared with 2-deoxy-1-LysoPS with oleic acid. Conversion of the serine residue into the threonine residue further increased the activity of MC degranulation both in vitro and in vivo. The resulting super agonist, 2-deoxy-LysoPT with C3-pH-p-O-C11, will be a useful tool to elucidate the mechanisms of stimulatory effect of LysoPS on MC degranulation. 相似文献
63.
Paweena Chuenwarin Azumi Shimazaki Masanori Shimizu Yuko Kobayashi Masakazu Katsumata 《Bioscience, biotechnology, and biochemistry》2016,80(3):452-460
Nondestructive evaluation of photosynthesis is a valuable tool in the field and laboratory. Delayed luminescence (DL) can reflect charge recombination through the backflow of electrons. However, DL detection has not yet been adapted for whole plants in Petri dishes. To compensate for differences in DL decay between sibling Arabidopsis plants grown under the same conditions, we developed a time-sequential double measurement method. Using this method, we examined the influence of photosynthetic electron flow inhibitors, and differences in the DL decay curves were categorized by considering the initial and late phases of the decay curves, as well as their intermediate slopes. The appearance of concavity and convexity in DL curves in Arabidopsis was different from unicellular algae, suggesting complexity in the photosynthetic machinery of higher plants. This detection method should be invaluable for evaluating photosynthetic defects in higher plants under sterile conditions without interrupting plant culture. 相似文献
64.
65.
Megan J. Agajanian Matthew P. Walker Alison D. Axtman Roberta R. Ruela-de-Sousa D. Stephen Serafin Alex D. Rabinowitz David M. Graham Meagan B. Ryan Tigist Tamir Yuko Nakamichi Melissa V. Gammons James M. Bennett Rafael M. Couñago David H. Drewry Jonathan M. Elkins Carina Gileadi Opher Gileadi Paulo H. Godoi Michael B. Major 《Cell reports》2019,26(1):79-93.e8
66.
67.
Kaftanovskaya E Motosugi N Kinoshita M Ozato K Wakamatsu Y 《Development, growth & differentiation》2007,49(9):691-698
Chromosomal abnormalities such as ploidy mosaicism have constituted a major obstacle to the successful nuclear transfer of adult somatic cell nuclei in lower vertebrates to date. Euploid mosaicism has been reported previously in well-developed amphibian transplants. Here, we investigated ploidy mosaicisms in well-developed transplants of adult somatic cell nuclei in medaka fish (Oryzias latipes). Donor nuclei from primary cultured cells from the adult caudal fin of a transgenic strain carrying the green fluorescent protein gene (GFP) were transferred to recipient nonenucleated eggs of a wild-type strain to produce 662 transplants. While some of the transplants developed beyond the body formation stage and several hatched, all exhibited varying degrees of abnormal morphology, limited growth and subsequent death. Twenty-one transplants, 19 embryos and two larvae, were selected for chromosomal analysis; all were well-developed 6-day-old or later embryonic stages exhibiting slight morphological abnormalities and the same pattern of GFP expression as that of the donor strain. In addition, all exhibited various levels of euploid mosaicism with haploid-diploid, haploid-triploid or haploid-diploid-triploid chromosome sets. No visible chromosomal abnormalities were observed. Thus, euploid mosaicism similar to that observed in amphibians was confirmed in well-developed nuclear transplants of fish. 相似文献
68.
Yamauchi J Miyamoto Y Murabe M Fujiwara Y Sanbe A Fujita Y Murase S Tanoue A 《Experimental cell research》2007,313(9):1886-1896
Valproic acid (VPA), a mood stabilizer and anticonvulsant, has a variety of neurotrophic functions; however, less is known about how VPA regulates neurite outgrowth. Here, using N1E-115 neuroblastoma cells as the model, we show that VPA upregulates Gadd45a to trigger activation of the downstream JNK cascade controlling neurite outgrowth. VPA induces the phosphorylation of c-Jun N-terminal kinase (JNK) and the substrate paxillin, while VPA induction of neurite outgrowth is inhibited by JNK inhibitors (SP600125 and the small JNK-binding peptide) or a paxillin construct harboring a Ser 178-to-Ala mutation at the JNK phosphorylation. Transfection of Gadd45a, acting through the effector MEKK4, leads to the phosphorylation of the JNK cascade. Conversely, knockdown of Gadd45a with siRNA reduces the effect of VPA. Taken together, these results suggest that upregulation of Gadd45a explains one of the mechanisms whereby VPA induces the neurotrophic effect, providing a new role of Gadd45a in neurite outgrowth. 相似文献
69.
Nishinaka T Doi Y Hashimoto M Hara R Shibata T Harada Y Kinosita K Noji H Yashima E 《Journal of biochemistry》2007,141(2):147-156
We have developed two experimental methods for observing Escherichia coli RecA-DNA filament under a fluorescence microscope. First, RecA-DNA filaments were visualized by immunofluorescence staining with anti-RecA monoclonal antibody. Although the detailed filament structures below submicron scale were unable to be measured accurately due to optical resolution limit, this method has an advantage to analyse a large number of RecA-DNA filaments in a single experiment. Thus, it provides a reliable statistical distribution of the filament morphology. Moreover, not only RecA filament, but also naked DNA region was visualized separately in combination with immunofluorescence staining using anti-DNA monoclonal antibody. Second, by using cysteine derivative RecA protein, RecA-DNA filament was directly labelled by fluorescent reagent, and was able to observe directly under a fluorescence microscope with its enzymatic activity maintained. We showed that the RecA-DNA filament disassembled in the direction from 5' to 3' of ssDNA as dATP hydrolysis proceeded. 相似文献
70.
Park BJ Tsunetsugu Y Kasetani T Hirano H Kagawa T Sato M Miyazaki Y 《Journal of physiological anthropology》2007,26(2):123-128
The purpose of this study is to examine the physiological effects of Shinrin-yoku (taking in the atmosphere of the forest). The subjects were 12 male students (22.8+/-1.4 yr). On the first day of the experiments, one group of 6 subjects was sent to a forest area, and the other group of 6 subjects was sent to a city area. On the second day, each group was sent to the opposite area for a cross check. In the forenoon, the subjects were asked to walk around their given area for 20 minutes. In the afternoon, they were asked to sit on chairs and watch the landscapes of their given area for 20 minutes. Cerebral activity in the prefrontal area and salivary cortisol were measured as physiological indices in the morning at the place of accommodation, before and after walking in the forest or city areas during the forenoon, and before and after watching the landscapes in the afternoon in the forest and city areas, and in the evening at the place of accommodation. The results indicated that cerebral activity in the prefrontal area of the forest area group was significantly lower than that of the group in the city area after walking; the concentration of salivary cortisol in the forest area group was significantly lower than that of the group in the city area before and after watching each landscape. The results of the physiological measurements show that Shinrin-yoku can effectively relax both people's body and spirit. 相似文献