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101.
Sugar- and salt-tolerant yeasts 总被引:3,自引:0,他引:3
K. Tokuoka 《Journal of applied microbiology》1993,74(2):101-110
102.
Takahiro Asami Makoto Ishii Ho Namkoong Kazuma Yagi Sadatomo Tasaka Takanori Asakura Shoji Suzuki Tetsuro Kamo Satoshi Okamori Hirofumi Kamata Haiyue Zhang Ahmed E. Hegab Naoki Hasegawa Tomoko Betsuyaku 《Cytotherapy》2018,20(3):302-313
Background
Pneumonia is the fourth leading cause of death worldwide, and Streptococcus pneumoniae is the most commonly associated pathogen. Increasing evidence suggests that mesenchymal stromal cells (MSCs) have anti-inflammatory roles during innate immune responses such as sepsis. However, little is known about the effect of MSCs on pneumococcal pneumonia.Methods
Bone marrow–derived macrophages (BMDMs) were stimulated with various ligands in the presence or absence of MSC-conditioned medium. For in vivo studies, mice intranasally-inoculated with S. pneumoniae were intravenously treated with MSCs or vehicle, and various parameters were assessed.Results
After stimulation with toll-like receptor (TLR) 2, TLR9 or TLR4 ligands, or live S. pneumoniae, TNF-α and interleukin (IL)–6 levels were significantly decreased, whereas IL-10 was significantly increased in BMDMs cultured in MSC-conditioned medium. In mice, MSC treatment decreased the number of neutrophils in bronchoalveolar lavage fluid (BALF) after pneumococcal infection, and this was associated with a decrease in myeloperoxidase activity in the lungs. Levels of proinflammatory cytokines, including TNF-α, IL-6, GM-CSF and IFN-γ, were significantly lower in MSC-treated mice, and the bacterial load in the lung after pneumococcal infection was significantly reduced. In addition, histopathologic analysis confirmed a decrease in the number of cells recruited to the lungs; however, lung edema, protein leakage into the BALF and levels of the antibacterial protein lipocalin 2 in the BALF were comparable between the groups.Conclusions
These results indicate that MSCs could represent a potential therapeutic application for the treatment of pneumonia caused by S. pneumoniae. 相似文献103.
Kensei Kobayashi Hisako Tonishi Taiki Tsuboi Nobushige Suzuki Takeo Kaneko Yoshinori Takano Yasuo Yasuyuki Muramatsu Hirofumi Hashimoto Masamichi Yamashita 《Biological Sciences in Space》2004,18(3):179-180
Complex organic compounds have been found in extraterrestrial bodies such as meteorites and comets. We confirmed the formation of complex organic compounds that contained amino acid precursors from a mixture of carbon monoxide (or methanol), ammonia and water by radiation or UV. Molecular weights of the complex organics were several thousands. Stability of the complex precursors was studied. When free amino acids were irradiated with gamma rays or synchrotron radiation, they easily decomposed. The complex precursors were, however, much more stable than free amino acid against irradiation. We propose to examine the formation and alteration of amino acid precursors in space by using exposed facility of ISS. 相似文献
104.
105.
106.
Kita K Watanabe T Ohsaka K Hayashi H Kubota Y Nagashima Y Aoki I Taniguchi H Noce T Inoue K Miki H Ogonuki N Tanaka H Ogura A Ogawa T 《Biology of reproduction》2007,76(2):211-217
Testicular germ cell transplantation into the seminiferous tubules is at present the only way to induce spermatogenesis from a given source of spermatogonial stem cells. Here we show an alternative method that harnesses the self-organizing ability of testicular somatic cells. The testicular cells of embryonic or neonatal mice or rats and of newborn pigs were dissociated into single cells. Each of them reorganized into a tubular structure following implantation into the subcutis of immunodeficient mice. When mouse germline stem (GS) cells derived from spermatogonial stem cells and expanded in culture were intermingled with testicular cells of rodents, they were integrated in the reconstituted tubules and differentiated beyond meiosis into spermatids. Normal offspring were produced by the microinjection of those spermatids into oocytes. This method could be applicable to various mammalian species and useful for producing functional gametes from GS cells in a xenoectopic environment. 相似文献
107.
Takahashi K Chibazakura T Sekine Y Yoshikawa H 《Biochemical and biophysical research communications》2007,355(2):426-430
While most studies involving transposition have focused on analyzing the detailed mechanisms of transposition, the cellular conditions under which transposition occurs remain to be elucidated. In Escherichia coli, papillation assay is a powerful tool for transpositional analysis and the isolation of mutants affecting transposition. On the other hand, while our assay system based on the E. coli papillation assay can detect transpositional events in Bacillus subtilis 168, it is not suitable for quantitating transposition frequency because blue papillae on the transposant colonies of B. subtilis are not countable. We succeeded in developing a new "GFP hop-on assay" system that facilitates quantitative detection of the transposition of the FACS-optimized GFP mutant gene. Our assay system is a step forward in understanding the cellular conditions under which transposition occurs. 相似文献
108.
A management policy for sika deer based on sex-specific hunting 总被引:3,自引:1,他引:2
H. Matsuda Koichi Kaji Hiroyuki Uno Hirofumi Hirakawa T. Saitoh 《Population Ecology》1999,41(2):139-149
We consider here a management policy for a sika deer (Cervus nippon) population in the eastern part of Hokkaido. Deer populations are characterized by a large intrinsic rate of population increase,
no significant density effects on population growth before population crash, and a relatively simple life history. Our goals
of management for the deer population are (1) to avoid irruption with severe damage to agriculture and forestry, (2) to avoid
the risk of extinction of the deer population, and (3) to maintain a sustainable yield of deer. To make a robust program on
the basis of uncertain information about the deer population, we consider three levels of relative population size and four
levels of hunting pressures. We also take into consideration a critical level for extinction, an optimal level, and an irruption
level. The hunting pressure for females is set to increase with the population size. We also recommend catching males if the
population size is between the critical and optimal levels and catching females and males if the population size is larger
than the optimal level. We must avoid cases of irruption or threatened population under various sets of uncertain parameter
values. The simulation results suggest that management based on sex-specific hunting is effective to diminish the annual variation
in hunting yield.
Received: April 8, 1998 / Accepted: December 25, 1998 相似文献
109.
Identification of ciliated sensory neuron-expressed genes in Caenorhabditis elegans using targeted pull-down of poly(A) tails 总被引:3,自引:0,他引:3 下载免费PDF全文
It is not always easy to apply microarray technology to small numbers of cells because of the difficulty in selectively isolating mRNA from such cells. We report here the preparation of mRNA from ciliated sensory neurons of Caenorhabditis elegans using the mRNA-tagging method, in which poly(A) RNA was co-immunoprecipitated with an epitope-tagged poly(A)-binding protein specifically expressed in sensory neurons. Subsequent cDNA microarray analyses led to the identification of a panel of sensory neuron-expressed genes. 相似文献
110.
The purposes of this study were to (a) describe the racket-arm kinematics and kinetics of the soft-tennis smash during match rallies, and (b) assess the characteristics of this smash vs. the laboratory-simulated smash of our previous study. In the current study we recorded soft-tennis smash motions during match play of the 3rd East Asian Games. Racket-arm anatomical joint angular velocity and anatomical joint torque were calculated from 3-D coordinate data of 13 collected motions obtained using the direct linear transformation procedure. The results showed that most of the maximum values of the anatomical joint torques were qualitatively smaller than those of the tennis serve. Peak elbow extension, shoulder internal rotation, and elbow varus torques in match play were significantly greater than values reported for laboratory-simulated conditions. The greater forward swing torques did not result in significantly different racket head velocity, possibly because there was a significantly shorter forward swing phase in match conditions. In particular, a clear peak of the elbow extension torque during the forward swing phase was the most characteristic pattern in the smashes under match conditions, for it was 160% greater than laboratory-simulated conditions. These results supported our hypothesis that racket-arm kinematic and kinetic characteristics of the smash under match conditions differ from those under laboratory-simulated conditions. Possible explanations include the time-pressure conditions of the competitive situation in a match, and the Hawthorne effect (Hudson et al., 1986), both of which alter performance between match conditions and laboratory-simulated conditions. 相似文献