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81.
Recent studies indicate that dopamine neurons in the ventral tegmental area (VTA) and substantia nigra pars compacta (SNc) convey distinct signals. To explore this difference, we comprehensively identified each area's monosynaptic inputs using the rabies virus. We show that dopamine neurons in both areas integrate inputs from a more diverse collection of areas than previously thought, including autonomic, motor, and somatosensory areas. SNc and VTA dopamine neurons receive contrasting excitatory inputs: the former from the somatosensory/motor cortex and subthalamic nucleus, which may explain their short-latency responses to salient events; and the latter from the lateral hypothalamus, which may explain their involvement in value coding. We demonstrate that neurons in the striatum that project directly to dopamine neurons form patches in both the dorsal and ventral striatum, whereas those projecting to GABAergic neurons are distributed in the matrix compartment. Neuron-type-specific connectivity lays a foundation for studying how dopamine neurons compute outputs. 相似文献
82.
Synaptic-like microvesicles (SLMVs) are morphological and functional equivalents of neuronal synaptic vesicles, and are responsible for the storage and secretion of classical neurotransmitters in various endocrine cells. Vacuolar H+-ATPase acidifies the internal space of these organelles and provides a driving force for the uptake of neurotransmitters. Thus, the luminal pH is an important determinant of the function of SLMVs, although its value in living cells is unknown. Here, we determined the luminal pH of SLMVs in living rat pinealocytes by means of an immunoelectronmicroscopic procedure basedon the distribution of an amphipathic amine, 3-(2,4-dinitroanilino)-3'-amino-N-methyldipropylamine (DAMP). Use of double-labeling techniques with antibodies against 2,4-dinitrophenol for DAMP and synaptophysin for SLMVs, and of frozen ultrathin sections enabled us to determine the number of immunogold particles for DAMP per microm2 of SLMVs. Using the density of gold particles, the luminal pH of SLMVs was calculated to be 5.11 +/- 0.01. Treatment with either 1 microm bafilomycin A1, a specific inhibitor of vacuolar H+-ATPase, or 50 mm ammonium chloride, a dissipater of the transmembrane pH gradient, increased the luminal pH to 6.04 +/- 0.07 and 6.05 +/- 0.11, respectively. Simultaneously, the lysosomal pH was found to be 5.14 +/- 0.07, which increased to 5.77 +/- 0.09 and 5.93 +/- 0.13 with bafilomycin A1 and ammonium chloride, respectively. It is concluded that the luminal pH of SLMVs is comparable to that of lysosomes in vivo. 相似文献
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85.
Satoru Kusama Isao Kusakabe Mitsuko Zama Kazuo Murakami Tsuneo Yasui 《Bioscience, biotechnology, and biochemistry》2013,77(6):1433-1440
The enzymatic preparation of laminaribiose was investigated in this research. When curdlan was hydrolyzed with the β-1,3-glucanase system of Streptomyces sp. K27-4, the hydrolyzate mainly consisted of glucose and laminaribiose in an approximate ratio of 1:1 by weight. Yeast strains selected in this study, effectively and selectively metabolized all of the glucose in the hydrolyzate, without any degradation of laminaribiose.By successive treatment of curdlan with the glucanase system and glucose-metabolizable yeast, 31 g of crystalline laminaribiose was obtained from l00g of curdlan. 相似文献
86.
Masahiro Ohsugi Mitsuko Nakazawa Koichi Ogata 《Bioscience, biotechnology, and biochemistry》2013,77(8):1293-1297
Biotin-vitamer formation from salicylic acid was investigated. Strains of Pseudomonas sp., No. 102 and No. 362, isolated from soil samples utilized well salicylic acid as a sole source of carbon, and formed biotin-vitamers in culture broth. The metabolites were partially purified by the methods of active carbon adsorption and anion-exchange column chromatography, and clarified as desthiobiotin, bisnordesthiobiotin and 7-keto-8-aminopelargonic acid. 相似文献
87.
Nineteen sesquiterpene pyridine alkaloids including 17 new compounds have been isolated from the 70% aq. EtOH extract of stem barks of Hippocratea excelsa. The structures of these compounds were elucidated by various spectroscopic means. 相似文献
88.
Mitsuko Sugiyama 《Journal of plant research》1997,110(1):45-54
The floral anatomy ofCamellia japonica is described and the origin of its multistaminate androecium is considered. Of significance is the observation that the complex
polyandry of the genus overlies a basic vascular obdiplostemonous pattern. This is evidenced by two systems of staminal bundles.
The first diverges from a set of five common petal-stamen bundles and subsequently divides further. The second set of five
staminal trunk bundles emerges from the central cylinder slightly above the petal-stamen bundles which are antepetalous. The
observations will aid phylogenetic reconstruction for members of the polyphyletic order Dilleniidae to whichCamellia belongs, and in which the polyandry has been too simply and sometimes incorrectly interpreted as a primitive condition. 相似文献
89.
Keima Abe Hideyuki Matsuura Mitsuko Ukai Hanako Shimura Hiroyuki Koshino 《Bioscience, biotechnology, and biochemistry》2017,81(10):1855-1860
Most Brassicaceae vegetables are ideal dietary sources of antioxidants beneficial for human health. Cardamine fauriei (Ezo-wasabi in Japanese) is a wild, edible Brassicaceae herb native to Hokkaido, Japan. To clarify the main antioxidative phytochemical, an 80% methanol extraction from the leaves was fractionated with Diaion® HP-20, Sephadex® LH-20, and Sep-Pak® C18 cartridges, and the fraction with strong antioxidant activity depending on DPPH method was purified by HPLC. Based on the analyses using HRESIMS and MS/MS, the compound might be N1, N14-diferuloylspermine. This rare phenol compound was chemically synthesized, whose data on HPLC, MS and 1H NMR were compared with those of naturally derived compound from C. fauriei. All results indicated they were the same compound. The radical-scavenging properties of diferuloylspermine were evaluated by ORAC and ESR spin trapping methods, with the diferuloylspermine showing high scavenging activities of the ROO·, O2·?, and HO· radicals as was those of conventional antioxidants. 相似文献
90.
Noriko Miyake Hiroyasu Tsukaguchi Eriko Koshimizu Akemi Shono Satoko Matsunaga Masaaki Shiina Yasuhiro Mimura Shintaro Imamura Tomonori Hirose Koji Okudela Kandai Nozu Yuko Akioka Motoshi Hattori Norishige Yoshikawa Akiko Kitamura Hae?Il Cheong Shoji Kagami Michiaki Yamashita Atsushi Fujita Satoko Miyatake Yoshinori Tsurusaki Mitsuko Nakashima Hirotomo Saitsu Kenichi Ohashi Naoko Imamoto Akihide Ryo Kazuhiro Ogata Kazumoto Iijima Naomichi Matsumoto 《American journal of human genetics》2015,96(4):555-564
We investigated complex genomic rearrangements (CGRs) consisting of triplication copy-number variants (CNVs) that were accompanied by extended regions of copy-number-neutral absence of heterozygosity (AOH) in subjects with multiple congenital abnormalities. Molecular analyses provided observational evidence that in humans, post-zygotically generated CGRs can lead to regional uniparental disomy (UPD) due to template switches between homologs versus sister chromatids by using microhomology to prime DNA replication—a prediction of the replicative repair model, MMBIR. Our findings suggest that replication-based mechanisms might underlie the formation of diverse types of genomic alterations (CGRs and AOH) implicated in constitutional disorders. 相似文献