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951.
952.
Tatsuo Nakahara Takashi Matsumoto Makoto Hirano Hideyuki Uchimura Hideyasu Yokoo Kaoru Nakamura Kenji Ishibashi Hitoshi Hirano 《Peptides》1985,6(6):1093-1099
Acute and chronic effects of γ-butyrolactone-γ-carbonyl-histidyl-prolinamide (DN-1417) were investigated on motor activity, dopamine (DA) metabolites and DA receptors in various brain regions of rats. The motor activity, as measured with Automex recorder, was enhanced after a single injection with DN-1417 (20 mg/kg, IP), and the motor stimulating action persisted during 21 daily injections. Acute DN-1417 elevated both homovanillic acid (HVA) and 3,4-dihydroxyphenylacetic acid (DOPAC) levels in 7 brain regions, prefrontal cortex polar, medial and lateral fields, nucleus accumbens, olfactory tubercles, amygdala and striatum. After chronic treatment for 7 days, the acute effect of DN-1417 on DA metabolites disappeared in all regions except for the striatum in which DN-1417 still increased HVA and DOPAC. The response of striatal DA metabolites was also observed after chronic treatment for 21 days. Chronic DN-1417 produced no significant change in 3H-spiperone binding in the prefrontal cortex, nucleus accumbens, olfactory tubercles and striatum, while striatal 3H-DA binding displaced by 30 nM spiperone was enhanced after chronic treatment. These results indicate that DN-1417 interacts with mesocortical, mesolimbic and nigrostriatal DA systems in the different modes of action. The lack of tolerance to motor hyperactivity, however, raises the question as to whether DN-1417-induced hyperactivity may be mediated by the activation of mesolimbic DA neurons. The involvement of nigrostriatal neurons in DN-1417-induced motor hyperactivity is suggested. 相似文献
953.
Kano Y Soda K Nakamura T Saitoh M Kawakami M Konishi F 《Cancer immunology, immunotherapy : CII》2007,56(6):771-781
Increased blood polyamine levels, often observed in cancer patients, have negative impacts on patient prognosis and are associated
with tumor progression. The purpose of our study was to examine the effects of polyamines on cellular immune function. Peripheral
blood mononuclear cells (PBMCs) from healthy volunteers were cultured with the human natural polyamines spermine, spermidine,
or putrescine, and the effects on immune cell function were examined. The correlation between post-operative changes in blood
polyamine levels and lymphokine-activated killer (LAK) activity was also examined in cancer patients. Spermine decreased the
adhesion of non-stimulated PBMCs to tissue culture plastic in a dose- and a time-dependent manner without affecting cell viability
or activity. This decrease in adhesion capacity was accompanied by a decrease in the number of CD11a bright-positive and CD56
bright-positive cells. Upon stimulation with interleukin 2 to activate LAK cytotoxicity, PBMCs cultured overnight with 100
or 500 μM spermine showed decreased cytotoxic activity against Daudi cells (91.5 ± 1.7 and 84.9 ± 3.0%, respectively (n = 6) compared to PBMC cultured without polyamines). In a group of 25 cancer patients, changes in blood spermine levels after
surgery were negatively correlated with changes in LAK cytotoxicity after surgery (r = −0.510, P = 0.008: n = 25). Increased blood spermine levels may be an important factor in the suppression of anti-tumor immune cell function. 相似文献
954.
955.
956.
Yamachika E Tsujigiwa H Matsubara M Hirata Y Kita K Takabatake K Mizukawa N Kaneda Y Nagatsuka H Iida S 《Journal of molecular histology》2012,43(2):223-233
Some progress has been made in development of methods to regenerate bone from cultured cells, however no method is put to
practical use. Here, we developed methods to isolate, purify, and expand mesenchymal stem cells (MSCs) from mouse compact
bone that may be used to regenerate bone in vivo. These cells were maintained in long-term culture and were capable of differentiating
along multiple lineages, including chondrocyte, osteocyte, and adipocyte trajectories. We used standard cell isolation and
culture methods to establish cell cultures from mouse compact bone and bone marrow. Cultures were grown in four distinct media
to determine the optimal composition of culture medium for bone-derived MSCs. Putative MSCs were subjected to flow cytometry,
alkaline phosphatase assays, immunohistochemical staining, and several differentiation assays to assess cell identity, protein
expression, and developmental potential. Finally, we used an in vivo bone formation assay to determine whether putative MSCs
were capable of regenerating bone. We found that compact bone of mice was a better source of MCSs than the bone marrow, that
growth in plastic flasks served to purify MSCs from hematopoietic cells, and that MSCs grown in basic fibroblast growth factor
(bFGF)-conditioned medium were, based on multiple criteria, superior to those grown in leukemia inhibitory factor-conditioned
medium. Moreover, we found that the MSCs isolated from compact bone and grown in bFGF-conditioned medium were capable of supporting
bone formation in vivo. The methods and results described here have implications for understanding MSC biology and for clinical
purpose. 相似文献
957.
Genetic diversity of soybean-nodulating rhizobia in Nepal in relation to climate and soil properties
Dinesh Adhikari Masakazu Kaneto Kazuhito Itoh Kousuke Suyama Bhanu B. Pokharel Yam K. Gaihre 《Plant and Soil》2012,357(1-2):131-145
Backgroud and aims
This study was conducted to reveal the genetic diversity of soybean-nodulating rhizobia in Nepal in relation to climate and soil properties.Method
A total of 102 bradyrhizobial strains were isolated from the root nodules of soybeans cultivated in 12 locations in Nepal varying in climate and soil properties, and their genetic diversity was examined based on 16S rDNA, ITS regions of 16S–23S rDNA, nodC and nifH. In vitro growth properties of some representative strains were examined to elucidate their characteristic distribution in Nepal.Results
Four species of the genus Bradyrhizobium were isolated, and B. japonicum dominated at temperate locations, while in subtropical locations, B. elkanii, B. yuanmingense, and B. liaoningense dominated at acidic, moderately acidic, and slightly alkaline soils, respectively. The relative nodule occupancies could not be fully explained by their in vitro growth properties. Similar nodC and nifH genes among the strains suggested co-evolution of these genes also in Nepal, probably through horizontal gene transfer.Conclusions
The influence of climate and soil pH on diversity at the sub-species level was revealed. It is concluded that the highly diverse climate and soils in Nepal might be conducive for the existence of diverse soybean rhizobial strains. 相似文献958.
Midori Hiramatsu Rei Edamatsu Shigeo Suzuki Masakazu Shimada Akitane Mori 《Neurochemical research》1990,15(8):821-825
Inbred mutant El mice are highly susceptible to convulsive seizures upon tossing stimulation. The levels of excitatory (e.g. glutamate and aspartate) and inhibitory amino acids [e.g. -aminobutyrate (GABA)] were examined in discrete regions of stimulated El mice [El(+)] non-stimulated El mice [El(-)] and ddY mice, which do not have convulsive disposition. In comparison with ddY, a general increased levels of aspartate, glutamate, glutamine, and taurine were detected in brain regions of El(-). The levels of GABA and glycine were almost the same in ddY and El(-). Compared to El(+), the levels of aspartate, glutamate, glutamine, and GABA in El(-) were either the same or higher. In the case of taurine and glycine, the levels in El(-) were either the same or lower than El(+). Alanine is special in that El(-) have a higher level than El(+) in hippocampus but lower in cerebellum. Furthermore, while marked changes were registered in several brain regions, none of the amino acids investigated showed any significant differences in the hypothalamus of three different groups of mice. 相似文献
959.
960.
Ahmed Aboul-Fotouh Mourad Seikou Nakamura Tsubasa Ueno Takahiro Minami Takanari Yagi Haruka Yasue Ryoko Komatsu Masayuki Yoshikawa Ashraf Mohamed Taye Mohamed Ahmed El-Moselhy Mohamed Montaser Khalifa Hisashi Matsuda 《Bioorganic & medicinal chemistry letters》2013,23(17):4813-4816
In a previous study, retrofractamide A from the fruit of Piper chaba was shown to promote adipogenesis in 3T3-L1 cells. In the present study, retrofractamide A and its derivatives were synthesized, and their adipogenetic effects in 3T3-L1 cells were examined. Among the tested compounds, an amide composed of 9-(3′,4′-methylenedioxyphenyl)-nona-2E,4E,8E-trienoic acid and an n-butyl or n-pentyl amine showed strongest activity. Moreover, the amide with the n-pentyl amine moiety significantly increased the uptake of 2-deoxyglucose into the cells, and also increased the mRNA levels of adiponectin, peroxisome proliferator-activated receptor γ2 (PPARγ2), glucose transporter 4 (GLUT4), fatty acid-binding protein (aP2), and CCAAT/enhancer-binding protein (C/EBP) α and β in a similar manner as the PPARγ agonist troglitazone, although it had less agonistic activity against PPARγ. 相似文献