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991.
Carboranes (dicarba-closo-dodecaboranes) are a class of carbon-containing polyhedral boron-cluster compounds having remarkable chemical and thermal stability, and hydrophobic character. These features may allow application of carboranes as a new hydrophobic core structure in biologically active molecules that interact hydrophobically with receptors. Here, we report the design and synthesis of novel androgen antagonists bearing a carborane moiety. These compounds, particularly 8a, 8c, and 9d, exhibited anti-androgenic activity similar to that of the well-known anti-androgen flutamide in reporter gene assay using NIH3T3 cells transfected with a human AR expression plasmid. The carborane cage seems to be a privileged hydrophobic pharmacophore for the expression of AR-antagonistic activity. 相似文献
992.
Major patterns of higher teleostean phylogenies: a new perspective based on 100 complete mitochondrial DNA sequences 总被引:28,自引:0,他引:28
Miya M Takeshima H Endo H Ishiguro NB Inoue JG Mukai T Satoh TP Yamaguchi M Kawaguchi A Mabuchi K Shirai SM Nishida M 《Molecular phylogenetics and evolution》2003,26(1):121-138
A recent preliminary study using complete mitochondrial DNA sequences from 48 species of teleosts has suggested that higher teleostean phylogenies should be reinvestigated on the basis of more intensive taxonomic sampling. As a second step towards the resolution of higher teleostean phylogenies, which have been described as the "(unresolved) bush at the top of the tree," we reanalyzed their relationships using mitogenomic data from 100 purposefully chosen species that fully represented all of the higher teleostean orders, except for the Batrachoidiformes. Unweighted and weighted maximum parsimony analyses were conducted with the data set that comprised concatenated nucleotide sequences from 12 protein-coding genes (excluding 3rd codon positions) and 21 transfer RNA (tRNA) genes (stem regions only) from each species. The resultant trees were well resolved and largely congruent, with most internal branches being supported by high statistical values. All major, comprehensive groups above ordinal level as currently defined in higher teleosts (with the exception of the Neoteleostei and several monotypic groups), such as the Eurypterygii, Ctenosquamata, Acanthomorpha, Paracanthopterygii, Acanthopterygii, and Percomorpha, appeared to be nonmonophyletic in the present tree. Such incongruities largely resulted from differences in the placement and/or limits of the orders Ateleopodiformes, Lampridiformes, Polymixiiformes, Ophidiiformes, Lophiiformes, Beryciformes, Stephanoberyciformes, and Zeiformes, long-standing problematic taxa in systematic ichthyology. Of these, the resulting phylogenetic positions of the Ophidiiformes and Lophiiformes were totally unexpected, because, although they have consistently been considered relatively primitive groups within higher teleosts (Paracanthopterygii), they were confidently placed within a crown group of teleosts, herein called the Percomorpha. It should be noted that many unexpected, but highly supported relationships were found within the Percomorpha, being highly promising for the next investigative step towards resolution of this remarkably diversified group of teleosts. 相似文献
993.
The terephthalate 1,2-dioxygenase system (TERDOS) was found in cell extracts of Delftia tsuruhatensis strain T7 (=IFO16741) grown in terephthalate-salt medium. The cell extract was separated by anion exchange chromatography to yield two fractions (R and Z) that were necessary for oxygenation of terephthalate with NADH and Fe(2+). The oxygenase component of TERDOS (TerZ) was purified from fraction Z by gel filtration chromatography to near homogeneity. An alpha(3)beta(3) subunit structure was deduced from the molecular masses of 235, 46 and 17 kDa of the native complex and the alpha- and beta-subunits, respectively. The N-terminal amino acid sequences of the two subunits of TerZ allowed polymerase chain reaction primers to be deduced and the DNA sequence of the alpha-subunit was determined. The amino acid sequence of the alpha-subunit (TerZalpha) showed significant similarities to the large subunits of multicomponent ring-hydroxylating oxygenases. Two motifs in the deduced amino acid sequence, a Rieske [2Fe-2S] center and a mononuclear Fe(II) binding site, were observed. Phylogenetic analyses indicated that TerZalpha and the large oxygenase component subunits ortho-halobenzoate 1,2-dioxygenase and salicylate-5-hydroxylase form a cluster that is distant from the rest of the large oxygenase subunits of multicomponent ring-hydroxylating oxygenases. 相似文献
994.
Watanabe S 《Behavioural processes》2002,60(1):35-39
Java sparrows were exposed to a mirror and a frosted mirror, a mirror and a live bird, a mirror and a live bird with frosted screen, a closed circuit TV monitor and a TV program or the closed circuit monitor and an upside down monitor. The birds showed strong preference for the self-image on the mirror, the live bird and the self-image on the monitor. They preferred almost equally to the mirror and the frosted live bird. These results suggest that the Java sparrows saw the self-image on the mirror as conspecific image. 相似文献
995.
Toyoshima Y Sekiguchi S Negishi T Nakamura S Ihara T Ishii Y Kyuwa S Yoshikawa Y Takahashi K 《Comparative medicine》2012,62(1):53-60
Proliferation and programmed cell death are important in the formation of morphologic structures and functional activity during CNS development. We used immunohistochemical and TUNEL methods to examine the proliferation and differentiation of neural cells in, distribution of apoptotic cells in, and microglial cell involvement in the removal of apoptotic cells from the fetal cerebral cortex of cynomolgus monkeys. At embryonic day (E) 50 and E80, the neuroepithelium contained many mitotic cells. Cells staining for PCNA (a nuclear marker of proliferating cells) were prominent in the proliferative zone, whereas cells positive for NeuN (a neuron-specific marker) were absent. GFAP staining for glial cells was positive in the neuroepithelium and radial glial fibers. Iba1-positive cells (that is, macrophages and microglia) were distributed throughout all regions at all time points but accumulated especially in the ventricular zone at E80. Apoptotic morphology (at E80) and TUNEL-positive cells (that is, containing DNA fragmentation; at E50 and E80) were observed also. At E120 and E150, most PCNA-positive cells were in the ventricular zone, and NeuN-positive cells were prominent in all layers except layer I-II at E120. GFAP immunoreactivity was detected mainly in cells with fine processes in the white matter. Neither apoptosis nor TUNEL-positive cells were detected at either E120 or E150. These results suggest that proliferation, migration, and neural cell death occur during midgestation (that is, E50 to E80) in fetal brain of cynomolgus macaques, whereas differentiation and maturation of neural cells occur after midgestation (E80). 相似文献
996.
Hamamoto K Aki T Shigyo M Sato S Ishida T Yano K Yoneyama T Yanagisawa S 《Journal of proteome research》2012,11(1):331-347
Illumination-induced greening in dark-grown plants is one of the most dramatic developmental processes known in plants. In our current study, we characterized the greening process of rice seedlings using comparative proteome analysis. We identified 886 different proteins in both whole cell lysates of illuminated and nonilluminated rice shoots and performed comparative proteome analysis based on the MS spectral intensities obtained for unique peptides from respective proteins. Furthermore, the changes in the levels of individual proteins were then compared with those of the corresponding mRNAs. The results revealed well-coordinated increases in the enzymes involved in the Calvin cycle at both the protein and mRNA levels during greening, and that the changes at the mRNA level precede those at the protein level. Although a much lower effect of illumination was found on the enzymes associated with glycolysis and the TCA cycle, coordinated increases during greening were evident for the enzymes involved in photorespiration and nitrogen assimilation as well as the components of the chloroplastic translational machinery. These results thus define the differential regulation of distinct biological systems during greening in rice and demonstrate the usefulness of comprehensive and comparative proteome analysis for the characterization of biological processes in plant cells. 相似文献
997.
Kiyoshi Ando Shigeru Obayashi Yuji Nagai Arata Oh-Nishi Takafumi Minamimoto Makoto Higuchi Takashi Inoue Toshio Itoh Tetsuya Suhara 《PloS one》2012,7(10)
Background
Positron Emission Tomography (PET) measurement was applied to the brain of the common marmoset, a small primate species, treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). The marmoset shows prominent Parkinson’s disease (PD) signs due to dopaminergic neural degeneration. Recently, the transgenic marmoset (TG) carrying human PD genes is developing. For phenotypic evaluations of TG, non-invasive PET measurement is considered to be substantially significant. As a reference control for TG, the brain of the MPTP-marmoset as an established and valid model was scanned by PET. Behavioral analysis was also performed by recording locomotion of the MPTP-marmoset, as an objective measure of PD signs.Methodology/Principal Findings
Marmosets received several MPTP regimens (single MPTP regimen: 2 mg/kg, s.c., per day for 3 consecutive days) were used for PET measurement and behavioral observation. To measure immobility as a central PD sign, locomotion of marmosets in their individual living cages were recorded daily by infrared sensors. Daily locomotion counts decreased drastically after MPTP regimens and remained diminished for several months or more. PET scan of the brain, using [11C]PE2I as a ligand of the dopamine (DA) transporter, was performed once several months after the last MPTP regimen. The mean binding potential (BPND) in the striatum (putamen and caudate) of the MPTP-marmoset group was significantly lower than that of the MPTP-free control group (n = 5 for each group). In the MPTP-marmosets, the decrease of BPND in the striatum closely correlated with the decrease in locomotion counts (r = 0.98 in putamen and 0.91 in caudate).Conclusion/Significance
The present characterization of neural degeneration using non-invasive PET imaging and of behavioral manifestation in the MPTP marmoset mimics typical PD characteristics and can be useful in evaluating the phenotype of TG marmosets being developed. 相似文献998.
It has been widely accepted that ocular dominance in the responses of visual cortical neurons can change depending on visual experience in a postnatal period. However, experience-dependent plasticity for orientation selectivity, which is another important response property of visual cortical neurons, is not yet fully understood. To address this issue, using intrinsic signal imaging and two-photon calcium imaging we attempted to observe the alteration of orientation selectivity in the visual cortex of juvenile and adult mice reared with head-mounted goggles, through which animals can experience only the vertical orientation. After one week of goggle rearing, the density of neurons optimally responding to the exposed orientation increased, while that responding to unexposed orientations decreased. These changes can be interpreted as a reallocation of preferred orientations among visually responsive neurons. Our obtained sensitivity profile for orientation selectivity showed a marked peak at 5 weeks and sustained elevation at 12 weeks and later. These features indicate the existence of a critical period between 4 and 7 weeks and residual orientation plasticity in adult mice. The presence of a dip in the sensitivity profile at 10 weeks suggests that different mechanisms are involved in orientation plasticity in childhood and adulthood. 相似文献
999.
1000.
After repeated exposures to two successive audiovisual stimuli presented in one frequent order, participants eventually perceive a pair separated by some lag time in the same order as occurring simultaneously (lag adaptation). In contrast, we previously found that perceptual changes occurred in the opposite direction in response to tactile stimuli, conforming to bayesian integration theory (bayesian calibration). We further showed, in theory, that the effect of bayesian calibration cannot be observed when the lag adaptation was fully operational. This led to the hypothesis that bayesian calibration affects judgments regarding the order of audiovisual stimuli, but that this effect is concealed behind the lag adaptation mechanism. In the present study, we showed that lag adaptation is pitch-insensitive using two sounds at 1046 and 1480 Hz. This enabled us to cancel lag adaptation by associating one pitch with sound-first stimuli and the other with light-first stimuli. When we presented each type of stimulus (high- or low-tone) in a different block, the point of simultaneity shifted to "sound-first" for the pitch associated with sound-first stimuli, and to "light-first" for the pitch associated with light-first stimuli. These results are consistent with lag adaptation. In contrast, when we delivered each type of stimulus in a randomized order, the point of simultaneity shifted to "light-first" for the pitch associated with sound-first stimuli, and to "sound-first" for the pitch associated with light-first stimuli. The results clearly show that bayesian calibration is pitch-specific and is at work behind pitch-insensitive lag adaptation during temporal order judgment of audiovisual stimuli. 相似文献