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The autonomic nervous system, which includes the sympathetic neurons and adrenal medulla, originates from the neural crest. Combining avian blood vessel-specific gene manipulation and mouse genetics, we addressed a long-standing question of how neural crest cells (NCCs) generate sympathetic and medullary lineages during embryogenesis. We found that the dorsal aorta acts as a morphogenetic signaling center that coordinates NCC migration and cell lineage segregation. Bone morphogenetic proteins (BMPs) produced by the dorsal aorta are critical for the production of the chemokine stromal cell-derived factor-1 (SDF -1) and Neuregulin 1 in the para-aortic region, which act as chemoattractants for early migration. Later, BMP signaling is directly involved in the sympatho-medullary segregation. This study provides insights into the complex developmental signaling cascade that instructs one of the earliest events of neurovascular interactions guiding embryonic development. 相似文献
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Kawai T Kawakita H Sugita K Saito K Tamada M Sugo T Kawamoto H 《Journal of agricultural and food chemistry》2002,50(5):1073-1076
This paper describes a cycloisomaltooligosaccharide glucanotransferase (CITase)-multilayer-immobilized porous hollow-fiber membrane used as an enzyme bioreactor. Dextran, a substrate with an average molecular mass of 43000, is converted into seven- to nine-glucose-membered cycloisomaltooligosaccharides, effective as a preventive for dental caries, aided by convective transport of the substrate to the vicinity of the enzyme through the pores. Epoxy-group-containing graft chains were uniformly appended onto the surface of pores throughout a porous hollow-fiber membrane by radiation-induced graft polymerization. Subsequently, a diethylamino group was introduced, as an anion-exchange moiety, to the graft chains, which caused the chains to expand toward the interior of the pores due to mutual electrostatic repulsion. The expanding graft chain provided multilayer binding sites for CITase. Fifty-five milligrams of adsorbed CITase per gram of membrane is equivalent to the degree of multilayer binding of 5. Finally, 80% of the multilayer-adsorbed CITase was immobilized via enzymatic cross-linking with transglutaminase to prevent the leakage of enzymes. CITase, with a degree of multilayer immobilization of 4, produced the target cycloisomaltooligosaccharides at a conversion yield of 55% in weight at 310 K during permeation by the dextran solution at a space velocity defined as the permeation rate divided by membrane volume of 6 per hour. 相似文献
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Katayama K Tomatsu M Kawahara S Yamauchi K Fuchu H Kodama Y Kawamura Y Muguruma M 《Journal of agricultural and food chemistry》2004,52(4):771-775
A novel angiotensin I-converting enzyme (ACE) inhibitory peptide (RMLGQTPTK; 9mer) from porcine skeletal troponin C was investigated for its inhibitory profile. This peptide was noncompetitive and as hydrophobic as the known ACE inhibitory peptides. Aminopeptidase M quickly hydrolyzed 9mer, resulting in production of MLGQTPTK and LGQTPTK with inhibitory activities similar to those of 9mer. The main hydrolysis product of 9mer with carboxypeptidase A and B was RMLGQTPT showing very weak activity. Most products derived from 9mer hydrolysis by ACE, aminopeptidase, or carboxypeptidase showed weak but definite ACE inhibitory activities. Thus, 9mer was estimated to be a wholly efficient inhibitor with these fragment peptides. 相似文献
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Masako Seki Makiko Chono Hitoshi Matsunaka Masaya Fujita Shunsuke Oda Katashi Kubo Chikako Kiribuchi-Otobe Hisayo Kojima Hidetaka Nishida Kenji Kato 《Breeding Science》2011,61(4):405-412
The genotypes of photoperiod response genes Ppd-B1 and Ppd-D1 in Japanese wheat cultivars were determined by a PCR-based method, and heading times were compared among genotypes. Most of the Japanese wheat cultivars, except those from the Hokkaido region, carried the photoperiod-insensitive allele Ppd-D1a, and heading was accelerated 10.3 days compared with the Ppd-D1b genotype. Early cultivars with Ppd-D1a may have been selected to avoid damage from preharvest rain. In the Hokkaido region, Ppd-D1a frequency was lower and heading date was late regardless of Ppd-D1 genotype, suggesting another genetic mechanism for late heading in Hokkaido cultivars. In this study, only 11 cultivars proved to carry Ppd-B1a, and all of them carried another photoperiod-insensitive allele, Ppd-D1a. The Ppd-B1a/Ppd-D1a genotype headed 6.7 days earlier than the Ppd-B1b/Ppd-D1a genotype, indicating a significant effect of Ppd-B1a in the genetic background with Ppd-D1a. Early-maturity breeding in Japan is believed to be accelerated by the introduction of the Ppd-B1a allele into medium-heading cultivars carrying Ppd-D1a. Pedigree analysis showed that Ppd-B1a in three extra-early commercial cultivars was inherited from ‘Shiroboro 21’ by early-heading Chugoku lines bred at the Chugoku Agriculture Experimental Station. 相似文献
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Katsunori Tanaka Yukari Akashi Kenji Fukunaga Tatsuya Yamamoto Yasheng Aierken Hidetaka Nishida Chun Lin Long Hiromichi Yoshino Yo-Ichiro Sato Kenji Kato 《Breeding Science》2013,63(2):183-196
Molecular analysis encouraged discovery of genetic diversity and relationships of cultivated melon (Cucumis melo L.). We sequenced nine inter- and intra-genic regions of the chloroplast genome, about 5500 bp, using 60 melon accessions and six reference accessions of wild species of Cucumis to show intra-specific variation of the chloroplast genome. Sequence polymorphisms were detected among melon accessions and other Cucumis species, indicating intra-specific diversification of the chloroplast genome. Melon accessions were classified into three subclusters by cytoplasm type and then into 12 subgroups. Geographical origin and seed size also differed between the three subclusters. Subcluster Ia contained small-seed melon from Southern Africa and South and East Asia and subcluster Ib mainly consisted of large-seed melon from northern Africa, Europe and USA. Melon accessions of subcluster Ic were only found in West, Central and Southern Africa. Our results indicated that European melon groups and Asian melon groups diversified independently and shared the same maternal lineage with northern African large-seed melon and Southern African small-seed melon, respectively. Cultivated melon of subcluster Ic may have been domesticated independently in Africa. The presence of 11 cytoplasm types in Africa strongly supported African origin of cultivated melon and indicated the importance of germplasm from Africa. 相似文献
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Nishida H Tanaka H Kitamura M Hatoya S Sugiura K Inaba T Nakayama M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(8):1071-1074
Progressive ataxia and paralysis in three Miniature Dachshunds were found to be caused by idiopathic sterile pyogranulomatous inflammation of epidural fat between T5 and L4. All dogs were managed by hemilaminectomy and removal of epidural compressive material. Surgical findings and histopathological evaluation were necessary to diagnose epidural pyogranulomatous inflammation. A dog did not regain motor and sensor function after the surgery. Two dogs had exhibited improved neurological function after the surgery, but they recurred. Oral cyclosporine treatment was useful for their long remission. Idiopathic sterile pyogranulomatous inflammation of epidural fat can be considered to be a cause of thoracolumbar myelopathy in dogs. 相似文献
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Atsuo Sugano Hidetaka Tsuchimoto Cho Cho Tun Susumu Asakawa Makoto Kimura 《Soil Science and Plant Nutrition》2005,51(1):51-60
PCR-DGGE analysis followed by sequencing was conducted to estimate the succession and the phylogenetic profile of the eubacterial communities responsible for the decomposition of rice straw (RS) that was incorporated into a rice field. Leaf sheath and leaf blade parts were separately put in nylon mesh bags, and were placed in the rice field soil under drained conditions during the off-cropping season and under flooded conditions after transplantation of rice. In addition, RS samples that had been placed under drained conditions in the off-cropping season were placed again in flooded rice field soil after transplantation of rice. DGGE patterns of the bacterial communities in the RS samples were classified into two groups, namely leaf sheaths and leaf blades. Principal component analysis of the DGGE patterns revealed the succession along with the duration of placement. These results indicated that the RS part (sheath or blade) mainly determined the structure of the bacterial communities responsible for the RS decomposition, followed by the duration of placement. Sequence analysis of the characteristic DGGE bands indicated that most of the closest relatives associated with the bands belonged to α-, β-, γ-, and δ-Proteobacteria, CFB group, and Spirochaetes. Some bands were closely related to Acidobacteria and Verrucomicrobia. CFB members and α-Proteobacteria predominated commonly in both RS parts, while γ- and δ-Proteobacteria, and Spirochaetes and β-Proteobacteria specifically colonized sheath and blade parts, respectively. In addition, Proteobacteria and CFB members characterized the differences in the bacterial communities under flooded or drained conditions. These results suggest that Proteobacteria, CFB group, and Spirochaetes were responsible for RS decomposition in rice field soil under both flooded and drained conditions. 相似文献