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排序方式: 共有111条查询结果,搜索用时 15 毫秒
1.
Stable genetic transformation of Larix gmelinii L. by particle bombardment of zygotic embryos 总被引:1,自引:0,他引:1
We report a new protocol for the stable transformation of Larix gmelinii. Thirty mature zygotic embryos precultured for 3 days on solid medium supplemented with benzyladenine were bombarded with plasmids pUC-GHG (GUS, HPT, and GFP genes) or pBI221-HPT (HPT and GUS genes). After a 2-month culture on selection medium, hygromycin-resistant calli appeared on the surfaces of the necrotic embryos. The frequencies of embryos with resistant calli were 18.4% and 17.4% in the transformations with pUC-GHG and pBI221-HPT DNA, respectively. More than 20 adventitious shoots formed from each of the transgenic calli. Of 17 elongated shoots selected for culturing on a rooting medium, five shoots rooted after 2 months. Expression of the GFP and GUS genes was detected in the resistant tissues by microscopic observations and by a histological GUS activity assay, respectively. PCR and Southern analysis confirmed the stable insertion of the introduced DNA into the genome. 相似文献
2.
Hiroaki Nabeka Keigo Uematsu Hiroko Takechi Tetsuya Shimokawa Kimiko Yamamiya Cheng Li Takuya Doihara Shouichiro Saito Naoto Kobayashi Seiji Matsuda 《PloS one》2014,9(12)
Because excessive glutamate release is believed to play a pivotal role in numerous neuropathological disorders, such as ischemia or seizure, we aimed to investigate whether intrinsic prosaposin (PS), a neuroprotective factor when supplied exogenously in vivo or in vitro, is up-regulated after the excitotoxicity induced by kainic acid (KA), a glutamate analog. In the present study, PS immunoreactivity and its mRNA expression in the hippocampal and cortical neurons showed significant increases on day 3 after KA injection, and high PS levels were maintained even after 3 weeks. The increase in PS, but not saposins, detected by immunoblot analysis suggests that the increase in PS-like immunoreactivity after KA injection was not due to an increase in saposins as lysosomal enzymes after neuronal damage, but rather to an increase in PS as a neurotrophic factor to improve neuronal survival. Furthermore, several neurons with slender nuclei inside/outside of the pyramidal layer showed more intense PS mRNA expression than other pyramidal neurons. Based on the results from double immunostaining using anti-PS and anti-GABA antibodies, these neurons were shown to be GABAergic interneurons in the extra- and intra-pyramidal layers. In the cerebral cortex, several large neurons in the V layer showed very intense PS mRNA expression 3 days after KA injection. The choroid plexus showed intense PS mRNA expression even in the normal rat, and the intensity increased significantly after KA injection. The present study indicates that inhibitory interneurons as well as stimulated hippocampal pyramidal and cortical neurons synthesize PS for neuronal survival, and the choroid plexus is highly activated to synthesize PS, which may prevent neurons from excitotoxic neuronal damage. To the best of our knowledge, this is the first study that demonstrates axonal transport and increased production of neurotrophic factor PS after KA injection. 相似文献
3.
Yumiko Kirihara Mayumi Takechi Kaoru Kurosaki Yuta Kobayashi Tsutomu Kurosawa 《Experimental Animals》2013,62(3):173-180
The combination of ketamine and xylazine is a widely used anesthetic for laboratory
animals. However, due to an abuse problem in Japan, ketamine has been specified as a
narcotic since 2007. Instead of using ketamine, Kawai et al. reported an
injectable formula with an equivalent effect to the mixture of ketamine and xylazine
[11]. The mixture of 0.3 mg/kg body weight (b.w.)
medetomidine (Med.), 4.0 mg/kg b.w. midazoram (Mid.), and 5.0 mg/kg b.w. butorphanol
(But.) produced an anesthetic duration of around 40 min in outbred ICR mice. However, the
anesthetic effect of the mixture for inbred mice strains remains unknown. Therefore, we
examined anesthetic effects of the mixture of Med., Mid., and But. in the BALB/c and
C57BL/6J strains. After intraperitoneal injection into mice, right front paw, left hind
paw, and tail pinch reflexes as well as corneal and righting reflexes were observed. Every
5 min, we scored each reflex category as 0 for reaction or 1 for no reaction. As long as
the total score was at least 4 out of 5, we considered the mixture as putting a mouse in a
surgical anesthetic state. The mixture produced an anesthetic duration of more than 45 min
in both strains of mice. These results indicate that the mixture of Med., Mid., and But.
can be a useful and effective anesthesia for the BALB/c and C57BL/6J strains of inbred
mice as well as outbred ICR mice. 相似文献
4.
Among vanadium's wide variety of biological functions, its insulin-mimetic effect is the most interesting and important. Recently, the vanadyl ion (+4 oxidation state of vanadium) and its complexes have been shown to normalize the blood glucose levels of streptozotocin-induced diabetic rats (STZ-rats). During our investigations to find more effective and less toxic vanadyl complexes, the vanadyl-methylpicolinate complex (VO-MPA) was found to exhibit higher insulin-mimetic activity and less toxicity than other complexes, as evaluated by both in vitro and in vivo experiments. Electron spin resonance (ESR) is capable of measuring the paramagnetic species in biological samples. We have developed the in vivo blood circulation monitoring-electron spin resonance (BCM-ESR) method to analyze the ESR signals due to stable organic radicals in real time. In the present investigation, we have applied this method to elucidate the relationship between the blood glucose normalizing effect of VO-MPA and the global disposition of paramagnetic vanadyl species. This paper describes the results of vanadyl species in the circulating blood of rats following intravenous administration of vanadyl compounds. ESR spectra due to the presence of vanadyl species were obtained in the circulating blood, and their pharmacokinetic parameters were estimated using compartment models. The results indicate that vanadyl species are distributed considerably to the peripheral tissues, as estimated by BCM-ESR, and eliminated from the body through the urine, as estimated by ESR at 77 K. The exposure of vanadyl species in the blood was found to be enhanced by VO-MPA treatment. Given these results, we concluded that the pharmacokinetic character of vanadyl species is closely related with the structure and antidiabetic activity of the vanadyl compounds. 相似文献
5.
Takechi M Takeuchi M Ota KG Nishimura O Mochii M Itomi K Adachi N Takahashi M Fujimoto S Tarui H Okabe M Aizawa S Kuratani S 《Journal of experimental zoology. Part B. Molecular and developmental evolution》2011,316(7):526-546
Because of their crucial phylogenetic positions, hagfishes, sharks, and bichirs are recognized as key taxa in our understanding of vertebrate evolution. The expression patterns of the regulatory genes involved in developmental patterning have been analyzed in the context of evolutionary developmental studies. However, in a survey of public sequence databases, we found that the large-scale sequence data for these taxa are still limited. To address this deficit, we used conventional Sanger DNA sequencing and a next-generation sequencing technology based on 454 GS FLX sequencing to obtain expressed sequence tags (ESTs) of the Japanese inshore hagfish (Eptatretus burgeri; 161,482 ESTs), cloudy catshark (Scyliorhinus torazame; 165,819 ESTs), and gray bichir (Polypterus senegalus; 34,336 ESTs). We deposited the ESTs in a newly constructed database, designated the "Vertebrate TimeCapsule." The ESTs include sequences from genes that can be effectively used in evolutionary developmental studies; for instance, several encode cartilaginous extracellular matrix proteins, which are central to an understanding of the ways in which evolutionary processes affected the skeletal elements, whereas others encode regulatory genes involved in craniofacial development and early embryogenesis. Here, we discuss how hagfishes, sharks, and bichirs contribute to our understanding of vertebrate evolution, we review the current status of the publicly available sequence data for these three taxa, and we introduce our EST projects and newly developed database. 相似文献
6.
Cytolytic activity of cytotoxin isolated from the venom of the Indian cobra (Naja naja) on experimental tumor cells was far stronger than that on normal cells such as peritoneal exudate cells, spleen cells, and erythrocytes of the rat. The effect on Yoshida sarcoma cells was temperature-dependent, being stronger at 37 degrees C than at 0 degrees C. Intramolecular disulfide linkages and free amino groups in the cytotoxin molecule were shown to be essential for the lytic action on the cell membrane. Yoshida sarcoma cells treated with 0.1 mM N-ethylmaleimide reduced the cytolytic action of the toxin. Antitumor activity of the cytotoxin toward a Yoshida sarcoma inoculated intraperitoneally into a rat was not observed. 相似文献
7.
8.
9.
Funayama N Nakatsukasa M Kuraku S Takechi K Dohi M Iwabe N Miyata T Agata K 《Zoological science》2005,22(10):1113-1122
Sponges (phylum Porifera) have remarkable regenerative and reconstitutive abilities and represent evolutionarily the oldest metazoans. To investigate sponge stem cell differentiation, we have focused on the asexual reproductive system in the freshwater sponge Ephydatia fluviatilis. During germination, thousands of stem cells proliferate and differentiate to form a fully functional sponge. As an initial step of our investigation of stem cell (archeocyte) differentiation, we isolated molecular markers for two differentiated cell types: spicule-making sclerocyte cells, and cells involved in innate immunity. Sclerocyte lineage-specific Ef silicatein shares 45% to 62% identity with other sponge silicateins. As in situ hybridization of Ef silicatein specifically detects archeocytes possibly committed to sclerocytes, as well as sclerocytes with an immature or mature spicule, therefore covering all the developmental stages, we conclude that Ef silicatein is a suitable sclerocyte lineage marker. Ef lectin, a marker for the cell type involved in innate immunity, shares 59% to 65% identity with the marine sponge Suberites domuncula galactose-binding protein (Sd GBP) and horseshoe crab Tachypleus tridentatus tachylectin1/lectinL6. Since Sd GBP and tachylectin1 are known to bind to bacterial lipopolysaccharides and inhibit the growth of bacteria, Ef lectin may have a similar function and be expressed in a specialized type of cell involved in defense against invading bacteria. Ef lectin mRNA and protein are not expressed in early stages of development, but are detected in late stages. Therefore, Ef lectin may be specifically expressed in differentiating and/or differentiated cells. We suggest Ef lectin as a marker for cells that assume innate immunity in freshwater sponges. 相似文献
10.
T Hasegawa S Izumi S Kurihara Y Ishizuka Y Ito A Takechi M Tsuchiya 《Acta cytologica》1985,29(3):363-366
In a high-volume cytology laboratory in the metropolitan Tokyo area, the incidence of cytologically diagnosed herpes infection in cervical scraping smears of the female genital tract was studied according to the year-by-year changes, age distribution, seasonal variation and types of cytologic alteration. The overall incidence over the 12 years studied was 0.007% (87 cases among 1,230,773 examined). The incidence varied from 0.003% to 0.005% in the early 1970s (except for 1973) and increased to 0.011% in the last three years (1980 to 1982). A large increase was noted in younger age groups in comparison with middle and older age groups. There was a tendency for the infection rate to be higher in the spring (0.011%) and lower in the fall (0.005%). Multinucleation and a ground-glass appearance were observed in the infected cells in almost every case while eosinophilic inclusion bodies were found in 20.7% of the cases. 相似文献