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111.
Functional transplantation of salivary gland cells differentiated from mouse early ES cells in vitro
Miyuki Kawakami Hiroshi Ishikawa Toshiaki Tachibana Akira Tanaka Izumi Mataga 《Human cell》2013,26(2):80-90
Atrophy or hypofunction of the salivary gland because of aging or disease causes hyposalivation and has an effect on the quality of life of patients, for example not only dry mouth but deterioration in mastication/deglutition disorder and the status of oral hygiene. Currently conducted therapies for atrophy or hypofunction of the salivary gland in clinical practice are only symptomatic treatments with drugs and artificial saliva, and therefore it is preferable to establish a radical therapy. At this time, as a fundamental investigation, by co-culturing mouse early ES (mEES-6) cells with human salivary gland-derived fibroblasts (hSG-fibro), differentiation of mEES-6 cells to salivary gland cells has been attempted. Also, the possibility of cell engraftment was examined. After identifying the cells which were co-cultured with GFP-transfected mEES-6 cells and hSG-fibro, the cells were transplanted into the submandibular gland of SCID mice, and the degree of differentiation into tissues was examined. The possibility of tissue functional reconstitution from co-cultured cells in a three-dimensional culture system was examined. Our results confirmed that the co-cultured cells expressed salivary gland-related markers and had an ability to generate neo-tissues by transplantation in vivo. Moreover, the cells could reconstitute gland structures in a three-dimensional culture system. By co-culture with hSG-fibro, mEES-6 cells were successfully differentiated into salivary gland cells which were transplantable and have tissue neogenetic ability. 相似文献
112.
Yoshikazu Izumi Kuninori Sato Yoshiki Tani Koichi Ogata 《Bioscience, biotechnology, and biochemistry》2013,77(11):2683-2684
Vitamin B6 is synthesized by green Cytisus scoparius callus and green Phellodendron amurense callus cultured on Linsmaier and Skoog Agar-medium with 10?5m of ±-naphthaleneacetic acid (NAA) and 10?6 m of 6-benzyladenine (BA). Even when thiamine and inositol were omitted from this medium, the growth and vitamin B6 content of Cytisus scoparius callus did not change. Vitamin B6 contents of clones of the calluses varied and were unstable during long-term subculture. Clonal selection was repeated to obtain stable strains with high vitamin B6 content, and the vitamin B6 content of one strain of green Cytisus scoparius callus became 4-times higher than that of the green leaves. 相似文献
113.
Mitsuyoshi Yoshikawa Toshifumi Kiyohara Teruo Iwasaki Izumi Yoshida 《Bioscience, biotechnology, and biochemistry》2013,77(9):1989-1990
We investigated the effects of compounds isolated from a methanolic extract of rose hips on melanin biosynthesis in B16 mouse melanoma cells and the possible mechanisms responsible for the inhibition of melanin biosynthesis. We found that, among the isolated compounds, quercetin was a particularly potent melanogenesis inhibitor. To reveal the mechanism for this inhibition, the effects on tyrosinase of B16 mouse melanoma were measured. Quercetin decreased the intracellular tyrosinase activity as well as the tyrosinase activity in a cell culture-free system. We also examined the cellular level of tyrosinase protein and found that quercetin dose-dependently inhibited tyrosinase protein expression. We consider from these results that the inhibition of melanogenesis by quercetin was due to the inhibition of both tyrosinase activity and of the protein expression. 相似文献
114.
Tsuyoshi Fujiwara Shinzo Izumi Patrick J. Brennan 《Bioscience, biotechnology, and biochemistry》2013,77(8):2301-2308
The disaccharide, 2,3-di-O-methyl-4-O-(3,6-di-O-methyl-β-d-glucopyranosyl)-l-rhamno-pyranose, the distal segment of phenolic glycolipid I, that is a specific antigen from Mycobacterium leprae, and some related disaccharides were synthesised as the glycosides of methyl 3-(p-hydroxyphenyl)propionate. The methyl 3-(p-hydroxyphenyl)propionate was coupled with 2,3,4-tri-O-acetyl-l-rhamnosyl bromide, deacetylated, acetonated, coupled with 2,4,6-tri-O-acetyl-3-O-methyl-d-glucosyl bromide, and converted into a variety of p-(2-methoxycarbonylethyl)phenyl 4-O-(3,6-di-O-methyl-d-glucopyranosyl)-containing disaccharides that are amenable to ready conjugation with protein carriers, thereby providing neo-glycoconjugates for the specific serodiagnosis of leprosy. 相似文献
115.
Masayoshi Tabata Takahiro Kido Masayuki Totani Takashi Murachi 《Bioscience, biotechnology, and biochemistry》2013,77(7):1909-1910
(22R,23R,24S)-3α,5-Cyclo-22,23-diacetoxy-5a-ergostan-6-one (2b) is a new key intermediate of some naturally occurring brassinosteroids such as brassinolide (la), castasterone (lb), teasterone (lc) and typhasterol (Id). The cycloketone 2b was prepared in 10 steps via (22R,23R,24S)-6p- benzyloxy-3a,5-cyclo-22,23-dihydroxy-5a-ergostane (5) from stigmasterol. 2b was treated with a catalytic amount of /7-toluenesulfonic acid and sodium bromide to give an enone (7b), which was oxidized with osmium tetroxide and derived to give a 2a,3a-acetonide (8b). 8b was easily separated from its isomer by the use of silica gel column chromatography. 8b was oxidized with tri- fluoroperacetic acid and deacetylated to give la. 8b was deacetylated and deacetonized to give lb. 2b was treated with dilute sulfuric acid in acetic acid to give a 3/^-acetate (10). 10 was treated with sodium hydroxide to give lc. 2b was treated with hydrobromic acid to give a 3/i-bromide (12), which was treated with silver acetate to give a 3a-acetate (13). 13 was treated with sodium hydroxide to give Id. 相似文献
116.
Yoshiki Tani Koichi Ogata Masao Ukita Tsuyoshi Nakamatsu Yoshikazu Izumi 《Bioscience, biotechnology, and biochemistry》2013,77(2):173-197
Escherichia freundii alkaline phosphatase was found in a membrane fraction and was purified by procedures involving spheroplast formation with lysozyme and EDTA, and DEAE-cellulose and Sephadex G-150 column chromatographies. Then this enzyme along with other phosphatases was investigated on the ability to transfer the phosphoryl group from p-nitrophenyl phosphate to pyridoxine. It was found that the ability of the transphosphorylation varied with these phosphatases. The transphosphorylation to hydroxy compounds such as alcohols, sugars and nucleosides was also compared. Escherichia freundii acid phosphatase showed the highest activity of transphosphorylation among phosphatases tested. The mechanism of transphosphorylation was discussed.An enzyme, pyridoxamine 5′-phosphate transaminase, was purified from the cell-free extract of Clostridium kainantoi. The purification procedures involved ammonium sulfate fractionation, protamine sulfate treatment and, DEAE-cellulose, hydroxylapatite, DEAE-Sephadex and Sephadex G-200 column chromatographies. The purified enzyme, which had approximately 2700-fold higher specific activity over the original extract, showed a single schlieren pattern in the ultracentrifuge. From the spectral analysis, it seemed that pyridoxamine 5′-phosphate transaminase did not contain pyridoxal 5′-phosphate as a prosthetic group. It was recognized that the transamination was accelerated by the addition of amino acid and was inhibited by diisopropyl phosphofluoride. Glutamic acid formed in the reaction was identified to be a D-isomer. A study on the substrate specificity showed that the enzyme might be possible to be specific for pyridoxamine 5′-phosphate.The extracellular formation of vitamin B6 was searched in marine and terrestrial microorganisms. Two bacterial strains were selected and were identified as Vibrio and Flavobacterium, respectively. Marine microorganisms showed the considerable formation of vitamin B6 and the presence of vitamin B6 in sea water was also recognized. The cultural and reaction conditions for vitamin B6 formation by these strains were investigated. Glycerol was commonly the most effective compound on vitamin B6 formation among the compounds tested. It was suggested that both bacteria did not have the control system on vitamin B6 biosynthesis by the amount of possible end products. 相似文献
117.
Yoshikazu Izumi Kuninori Sato Yoshiki Tani Koichi Ogata 《Bioscience, biotechnology, and biochemistry》2013,77(6):1335-1340
The 7-keto-8-aminopelargonic acid (KAPA) synthetase activities of cell-free extracts from various bacteria were investigated. The experiments on the substrate specificity of KAPA synthetase, using crude cell-free extracts from bacteria having high enzyme activity, showed that l-serine and pyruvic acid could replace l-alanine, but that, when the enzyme was partially purified, these compounds were not effective. Many kinds of amino acids such as l-cysteine, l-serine, d-alanine, glycine, d-histidine, and l-histidine, inhibited the enzyme activity. This inhibition was found to be competitive with l-alanine. Pyridoxal 5′-phosphate, which is a cofactor of the enzyme, also inhibited the enzyme activity at high concentrations. The repression of KAPA synthetase by biotin occurred in Bacillus subtilis and B. sphaericus but not in Micrococcus roseus and Pseudomonas fluorescens, even at a concentration of 1000 mµg per ml of biotin. 相似文献
118.
Background
The common grey wolf (Canis lupus) is found throughout the entire Northern hemisphere and preys on many kinds of mammals. The urine of the wolf contains a number of volatile constituents that can potentially be used for predator–prey chemosignalling. Although wolf urine is put to practical use to keep rabbits, rodents, deer and so on at bay, we are unaware of any prior behavioural studies or chemical analyses regarding the fear-inducing impact of wolf urine on laboratory mice.Methodology/Principal Findings
Three wolf urine samples harvested at different times were used in this study. All of them induced stereotypical fear-associated behaviors (i.e., avoidance and freezing) in female mice. The levels of certain urinary volatiles varied widely among the samples. To identify the volatiles that provoked avoidance and freezing, behavioural, chemical, and immunohistochemical analyses were performed. One of the urine samples (sample C) had higher levels of 2,6-dimethylpyrazine (DMP), trimethylpyrazine (TMP), and 3-ethyl-2,5-dimethyl pyrazine (EDMP) compared with the other two urine samples (samples A and B). In addition, sample C induced avoidance and freezing behaviours more effectively than samples A and B. Moreover, only sample C led to pronounced expression of Fos-immunoreactive cells in the accessory olfactory bulb (AOB) of female mice. Freezing behaviour and Fos immunoreactivity were markedly enhanced when the mice were confronted with a mixture of purified DMP, TMP, and EDMP vs. any one pyrazine alone.Conclusions/Significance
The current results suggest that wolf urinary volatiles can engender aversive and fear-related responses in mice. Pyrazine analogues were identified as the predominant active components among these volatiles to induce avoidance and freezing behaviours via stimulation of the murine AOB. 相似文献119.
Izumi Uno Takashi Kozaka Daisuke Miwa Yoji Kitamura Mohammad Anwar-ul Azim Kazuma Ogawa Junichi Taki Seigo Kinuya Kazuhiro Shiba 《PloS one》2016,11(1)
Purpose
To develop a superior VAChT imaging probe for SPECT, radiolabeled (-)-OIDV and (+)-OIDV were isolated and investigated for differences in their binding affinity and selectivity to VAChT, as well as their in vivo activities.Procedures
Radioiodinated o-iodo-trans-decalinvesamicol ([125I]OIDV) has a high binding affinity for vesicular acetylcholine transporter (VAChT) both in vitro and in vivo. Racemic [125I]OIDV was separated into its two optical isomers (-)-[125I]OIDV and (+)-[125I]OIDV by HPLC. To investigate VAChT binding affinity (Ki) of two OIDV isomers, in vitro binding assays were performed. In vivo biodistribution study of each [125I]OIDV isomer in blood, brain regions and major organs of rats was performed at 2,30 and 60 min post-injection. In vivo blocking study were performed to reveal the binding selectivity of two [125I]OIDV isomers to VAChT in vivo. Ex vivo autoradiography were performed to reveal the regional brain distribution of two [125I]OIDV isomers and (-)-[123I]OIDV for SPECT at 60 min postinjection.Results
VAChT binding affinity (Ki) of (-)-[125I]OIDV and (+)-[125I]OIDV was 22.1 nM and 79.0 nM, respectively. At 2 min post-injection, accumulation of (-)-[125I]OIDV was the same as that of (+)-[125I]OIDV. However, (+)-[125I]OIDV clearance from the brain was faster than (-)-[125I]OIDV. At 30 min post-injection, accumulation of (-)-[125I]OIDV (0.62 ± 0.10%ID/g) was higher than (+)-[125I]OIDV (0.46 ± 0.07%ID/g) in the cortex. Inhibition of OIDV binding showed that (-)-[125I]OIDV was selectively accumulated in regions known to express VAChT in the rat brain, and ex vivo autoradiography further confirmed these results showing similar accumulation of (-)-[125I]OIDV in these regions. Furthermore, (-)-[123I]OIDV for SPECT showed the same regional brain distribution as (-)-[125I]OIDV.Conclusion
These results suggest that radioiodinated (-)-OIDV may be a potentially useful tool for studying presynaptic cholinergic neurons in the brain. 相似文献120.
Renato T. Souza Jose G. Cecatti Renato Passini Jr. Ricardo P. Tedesco Giuliane J. Lajos Marcelo L. Nomura Patricia M. Rehder Tabata Z. Dias Samira M. Haddad Rodolfo C. Pacagnella Maria L. Costa Brazilian Multicenter Study on Preterm Birth study group 《PloS one》2016,11(2)