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991.
Ueki Atsuko Takehara Toshiaki Ishioka Gen Kaku Nobuo Ueki Katsuji 《Applied microbiology and biotechnology》2017,101(22):8267-8277
Applied Microbiology and Biotechnology - Biological soil disinfestation (BSD) involves elimination of soil-borne plant pathogens in an environmentally friendly manner. Two anaerobic bacterial... 相似文献
992.
Hikari Kurogi Atsuko Takahashi Maya Isogai Marimu Sakumoto Takashi Takijiri Akiko Hori Tetsuo Furuno Tetsuo Koike Tetsumasa Yamada Tokiko Nagamura-Inoue Masayo Sakaki-Yumoto 《Biotechnology journal》2021,16(6):2000558
Mesenchymal stromal cells (MSCs) have been isolated from numerous sources and are potentially therapeutic against various diseases. Umbilical cord-derived MSCs (UC-MSCs) are considered superior to other tissue-derived MSCs since they have a higher proliferation rate and can be procured using less invasive surgical procedures. However, it has been recently reported that 2D culture systems, using conventional cell culture flasks, limit the mass production of MSCs for cell therapy. Therefore, the development of alternative technologies, including microcarrier-based cell culture in bioreactors, is required for the large-scale production and industrialization of MSC therapy. In this study, we aimed to optimize the culture conditions for UC-MSCs by using a good manufacturing practice (GMP)-compatible serum-free medium, developed in-house, and a small-scale (30 mL) bioreactor, which was later scaled up to 500 mL. UC-MSCs cultured in microcarrier-based bioreactors (MC-UC-MSCs) showed characteristics equivalent to those cultured statically in conventional cell culture flasks (ST-UC-MSCs), fulfilling the minimum International Society for Cellular Therapy criteria for MSCs. Additionally, we report, for the first time, the equivalent therapeutic effect of MC-UC-MSCs and ST-UC-MSCs in immunodeficient mice (graft-versus-host disease model). Lastly, we developed a semi-automated cell dispensing system, without bag-to-bag variation in the filled volume or cell concentration. In summary, our results show that the combination of our GMP-compatible serum-free and microcarrier-based culture systems is suitable for the mass production of MSCs at an industrial scale. Further improvements in this microcarrier-based cell culture system can contribute to lowering the cost of therapy and satisfying several unmet medical needs. 相似文献
993.
Ichthyological Research - The reproductive system of the red stingray Hemitrygon akajei was described from 1,418 specimens, 682 males and 736 females, sampled year-round (2003–2014) from... 相似文献
994.
Ca2+ ion effect on protoplasmic streaming in an internodal cell of Nitella has been investigated for various temperatures. We have found that the protoplasmic streaming at low temperature is remarkably affected by the Ca2+ ions in the internodal cell but larger concentrations of the Ca2+ ions are needed to suppress the streaming velocity at higher temperatures. These streaming behaviors of the protoplasm, furthermore, have been elucidated on the basis of the reaction equations which take into account ATP hydrolysis due to actin-myosin molecules and inactivity of the molecules due to the Ca2+ ions. 相似文献
995.
Atsuko Matsushita Grace Pyon Masashi Kawasaki 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2013,199(7):583-599
Roles of the time coding electrosensory system in the novelty responses of a pulse-type gymnotiform electric fish, Brachyhypopomus, were examined behaviorally, physiologically, and anatomically. Brachyhypopomus responded with the novelty responses to small changes (100 μs) in time difference between electrosensory stimulus pulses applied to different parts of the body, as long as these pulses were given within a time period of ~500 μs. Physiological recording revealed neurons in the hindbrain and midbrain that fire action potentials time-locked to stimulus pulses with short latency (500–900 μs). These time-locked neurons, along with other types of neurons, were labeled with intracellular and extracellular marker injection techniques. Light and electron microscopy of the labeled materials revealed neural connectivity within the time coding system. Two types of time-locked neurons, the pear-shaped cells and the large cells converge onto the small cells in a hypertrophied structure, the mesencephalic magnocellular nucleus. The small cells receive a calyx synapse from a large cell at their somata and an input from a pear-shaped cell at the tip of their dendrites via synaptic islands. The small cells project to the torus semicircularis. We hypothesized that the time-locked neural signals conveyed by the pear-shaped cells and the large cells are decoded by the small cells for detection of time shifts occurring across body areas. 相似文献
996.
Mitsuru Nakamura Atsuko Tsunoda Yusuke Furukawa Takao Sakai Masaki Saito 《FEBS letters》1997,400(3):39
Incorporation and metabolism of exogenous GM3 in human myelogenous leukemia HL-60 cells were analyzed using 3H-labeled GM3 ([3H]GM3). [3H]GM3 was rapidly internalized into the cells (trypsin-resistant fraction) 8 times more than the control, 3H-labeled GM1 ([3H]GM1). In addition, not only incorporation but also metabolism of [3H]GM3 was more rapid than [3H]GM1 in HL-60 cells. Moreover, one of the metabolites was found to co-migrate with ceramide in thin-layer chromatography analysis and ceramide formation from exogenous GM3 is more rapid than that from exogenous GM1. These results suggested that there would be some preferential mechanism to produce ceramide from differentiation-inducible GM3 in HL-60 cells rather than from non-inducing GM1. 相似文献
997.
Takayuki Ohtomo Atsuko Hoshino Masako Yajima Akiharu Tsuchiya Atsushi Momose Kouichi Tanonaka Hiroo Toyoda Tetsuta Kato Junji Yamada 《Histochemistry and cell biology》2013,140(2):223-232
Acyl-CoA thioesterases (Acots) are enzymes that catalyze the hydrolysis of fatty acyl-CoAs to free fatty acids and coenzyme A, and have the potential to regulate the intracellular levels of these molecules. In this study, we show that a cytosolic isoform, Acot1, is expressed and distributed in immature adipocytes located in the perivascular region of the white adipose tissue (WAT) of rats. Immunoblot analyses detected Acot1 in all of the WATs examined, while immunohistochemistry revealed positively stained layered structures surrounding the adventitia of blood vessels in the subcutaneous WAT. When the subcutaneous WAT was digested with collagenase and centrifuged, Acot1 was recovered in the stromal vascular fraction (SVF), and not in the large mature adipocytes. In the SVF, undigested cells attached to short tubular fragments of blood vessels showed positive immunostaining, as well as a proportion of the dispersed cells. These fibroblast-like cells contained fine particulate lipid droplets, stained by oil-red O dye, in their cytoplasm, or expressed fatty acid-binding protein 4, an adipocyte marker. After induction of adipocyte differentiation following a 15-day preculture without insulin, the dedifferentiated cells showed increased Acot1 expression with a diffuse distribution throughout the cytosol. These findings suggest that Acot1 expression is transiently upregulated at an early stage of adipocyte maturation, possibly to maintain cytosolic acyl-CoAs below a certain level until the cells acquire their full capability for fat storage. 相似文献
998.
999.
Neurite outgrowth promoting activity of marine algae from Japan against rat adrenal medulla pheochromocytoma cell line, PC12D 总被引:2,自引:0,他引:2
We screened for biological activity which induces neurite outgrowth in vitro from 300 species of marine algae from along the Japan coast for possible use as a treatment for the lack of neurotrophic
factor which is considered to be a cause of Alzheimer's disease. In this study, we evaluated the neurite outgrowth promoting
activity in a rat adrenal medulla pheochromocytoma cell line, PC12D, using a low level of NGF (nerve growth factor). Although
most of the samples had no activity, MeOH extract from a brown alga, Sargassum macrocarpum and PBS extract from a red alga, Jania adharens, exhibited neurite outgrowth promoting activity and induced neuron specific dendrites and axons from the surfaces of PC12D
cells. The active substance present in S. macrocarpumseemed to be lipid and heat stable with molecular weight of around 500 to 1000. These results suggest that marine algae may
constitute a good source for development of promising novel agents with neurotrophic activity in brain nerve systems for future
use in treatment of Alzheimer's disease.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
1000.
Thymosin α1 restores NK-cell activity and prevents tumor progression in mice immunosuppressed by cytostatics or X-rays 总被引:1,自引:0,他引:1
Yukio Umeda Atsuko Sakamoto Junko Nakamura Hideo Ishitsuka Yasuo Yagi 《Cancer immunology, immunotherapy : CII》1983,15(2):78-83
The effect of thymosin against tumor progression was examined in mice immunosuppressed by cytostatics or X-ray irradiation. When pretreated with cytostatic agents, such as 5-fluorouracil (5-FU) or BCNU, or by X-ray, and then inoculated with P388 or L1210 leukemias, mice died rapidly within a few days. In these systems, thymosin alpha 1 given concomitantly with the cytostatic agents or after X-irradiation prevented rapid death and extended survival, although the mice eventually died with leukemia like normal mice inoculated with cells of the same tumor. Rapid death in the 5-FU-treated mice was also prevented by adoptive transfer of spleen cells from the donor mice if these had been treated with 5-FU plus thymosin alpha 1, but not if they had received 5-FU alone. However, the restorative activity of the donor spleen cells was abrogated by treatment with anti-asialo GM1, but not by treatment with anti-Thy 1 or anti-mouse Ig serum, suggesting that the effector cells in the spleen are NK cells. In fact, thymosin alpha 1, when given concomitantly with 5-FU or after X-irradiation, maintained the NK activity of spleen, which was damaged by treatment with 5-FU or X-irradiation alone. The present study indicates that thymosin alpha 1 exerts a preventive activity against progression of leukemias at least in part through an effect on NK cells or their progenitor cells. 相似文献