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11.
Specific lysyl residues of trout testis histones H3 and H4 are methylated partially during rainbow trout spermatogenesis. Histones H1, H2A, H2B, and protamine are not methylated. The single site (lysine 20) in histone H4 and the two major sites (lysines 9 and 27) in histone H3 are homologous to those determined for other organisms, but an additional minor site (lysine 4) occurs in histone H3. As described for calf thymus, both histones H3 and H4 contain epsilon-N-mono- and dimethyllysine, while histone H3 contains in addition, epsilon-N-trimethyllysine. The trout-specific histone H6, which accounts for 0.5 to 1.0% of total histone, contains a sequence for residues 3 to 5,-Arg-Lys-Ser-, which is the same as one methylated in histones H3, at lysines 9 and 27. However, histone H6 yields only trace amounts of [3H]methyl incorporation and no detectable methyllysines on amino acid analysis. 相似文献
12.
High-Mr (greater than 2 X 10(6)) hyaluronic acid (about 82 micrograms/ml) was found for the first time in rabbit pericardial fluid. Biosynthetic experiments with minced pericardium from rabbit showed that the high-Mr hyaluronic acid in the pericardial fluid was actively synthesized by the pericardium from [3H]glucosamine. 相似文献
13.
Takahiro Shibata Fumie Nakashima Kazuya Honda Yu-Jhang Lu Tatsuhiko Kondo Yusuke Ushida Koichi Aizawa Hiroyuki Suganuma Sho Oe Hiroshi Tanaka Takashi Takahashi Koji Uchida 《The Journal of biological chemistry》2014,289(47):32757-32772
Toll-like receptors (TLRs) play a key role in linking pathogen recognition with the induction of innate immunity. They have been implicated in the pathogenesis of chronic inflammatory diseases, representing potential targets for prevention/treatment. Vegetable-rich diets are associated with the reduced risk of several inflammatory disorders. In the present study, based on an extensive screening of vegetable extracts for TLR-inhibiting activity in HEK293 cells co-expressing TLR with the NF-κB reporter gene, we found cabbage and onion extracts to be the richest sources of a TLR signaling inhibitor. To identify the active substances, we performed activity-guiding separation of the principal inhibitors and identified 3-methylsulfinylpropyl isothiocyanate (iberin) from the cabbage and quercetin and quercetin 4′-O-β-glucoside from the onion, among which iberin showed the most potent inhibitory effect. It was revealed that iberin specifically acted on the dimerization step of TLRs in the TLR signaling pathway. To gain insight into the inhibitory mechanism of TLR dimerization, we developed a novel probe combining an isothiocyanate-reactive group and an alkyne functionality for click chemistry and detected the probe bound to the TLRs in living cells, suggesting that iberin disrupts dimerization of the TLRs via covalent binding. Furthermore, we designed a variety of iberin analogues and found that the inhibition potency was influenced by the oxidation state of the sulfur. Modeling studies of the iberin analogues showed that the oxidation state of sulfur might influence the global shape of the isothiocyanates. These findings establish the TLR dimerization step as a target of food-derived anti-inflammatory compounds. 相似文献
14.
Uchino S Wada H Honda S Nakamura Y Ondo Y Uchiyama T Tsutsumi M Suzuki E Hirasawa T Kohsaka S 《Journal of neurochemistry》2006,97(4):1203-1214
A class of scaffolding protein containing the post-synaptic density-95/Dlg/ZO-1 (PDZ) domain is thought to be involved in synaptic trafficking of alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors during development. To clarify the molecular mechanism of AMPA receptor trafficking, we performed a yeast two-hybrid screening system using the cytoplasmic tail of the GluR1 subunit of AMPA receptor as a bait and identified a synaptic molecule, Shank3/ProSAP2, as a GluR1 subunit-interacting molecule. Shank3 is a PDZ domain-containing multidomain protein and is predominantly expressed in developing neurons. Using the glutathione S-transferase pull-down assay and immunoprecipitation technique we demonstrated that the GluR1 subunit directly binds to the PDZ domain of Shank3 via its carboxyl terminal PDZ-binding motif. We raised anti-Shank3 antibody to investigate the expression of Shank3 in cortical neurons. The pattern of Shank3 immunoreactivity was strikingly punctate, mainly observed in the spines, and closely matched the pattern of post-synaptic density-95 immunoreactivity, indicating that Shank3 is colocalized with post-synaptic density-95 in the same spines. When Shank3 and the GluR1 subunit were overexpressed in primary cortical neurons, they were also colocalized in the spines. Taken together with the biochemical interaction of Shank3 with the GluR1 subunit, these results suggest that Shank3 is an important molecule that interacts with GluR1 AMPA receptor at synaptic sites of developing neurons. 相似文献
15.
Ise W Nakamura K Shimizu N Goto H Fujimoto K Kaminogawa S Hachimura S 《Journal of immunology (Baltimore, Md. : 1950)》2005,175(2):829-838
Oral tolerance is systemic immune hyporesponsiveness induced by the oral administration of soluble Ags. Hyporesponsiveness of Ag-specific CD4 T cells is responsible for this phenomenon. However, the molecular mechanisms underlying the hyporesponsive state of these T cells are not fully understood. In the present study, we investigated the ability of orally tolerized T cells to form conjugates with Ag-bearing APCs and to translocate TCR, protein kinase C-theta (PKC-theta), and lipid rafts into the interface between T cells and APCs. Orally tolerized T cells were prepared from the spleens of OVA-fed DO11.10 mice. Interestingly, the orally tolerized T cells did not show any impairment in the formation of conjugates with APCs. The conjugates were formed in a LFA-1-dependent manner. Upon antigenic stimulation, the tolerized T cells could indeed activate Rap1, which is critical for LFA-1 activation and thus cell adhesion. However, orally tolerized T cells showed defects in the translocation of TCR, PKC-theta, and lipid rafts into the interface between T cells and APCs. Translocation of TCR and PKC-theta to lipid raft fractions upon antigenic stimulation was also impaired in the tolerized T cells. Ag-induced activation of Vav, Rac1, and cdc42, which are essential for immunological synapse and raft aggregation, were down-regulated in orally tolerized T cells. These results demonstrate that orally tolerized T cells can respond to specific Ags in terms of conjugate formation but not with appropriate immunological synapse formation. This may account for the hyporesponsive state of orally tolerized T cells. 相似文献
16.
Kan Fujino Masayuki Horie Tomoyuki Honda Shoko Nakamura Yusuke Matsumoto Ivo M. B. Francischetti Keizo Tomonaga 《PloS one》2012,7(12)
Bornavirus, a non-segmented, negative-strand RNA viruses, is currently classified into several genetically distinct genotypes, such as Borna disease virus (BDV) and avian bornaviruses (ABVs). Recent studies revealed that bornavirus genotypes show unique sequence variability in the putative 5′ untranslated region (5′ UTR) of X/P mRNA, a bicistronic mRNA for the X protein and phosphoprotein (P). In this study, to understand the evolutionary relationship among the bornavirus genotypes, we investigated the functional interaction between the X and P proteins of four bornavirus genotypes, BDV, ABV genotype 4 and 5 and reptile bornavirus (RBV), the putative 5′ UTRs of which exhibit variation in the length. Immunofluorescence and immunoprecipitation analyses using mammalian and avian cell lines revealed that the X proteins of bornaviruses conserve the ability to facilitate the export of P from the nucleus to the cytoplasm via interaction with P. Furthermore, we showed that inter-genotypic interactions may occur between X and P among the genotypes, except for X of RBV. In addition, a BDV minireplicon assay demonstrated that the X and P proteins of ABVs, but not RBV, can affect the polymerase activity of BDV. This study demonstrates that bornaviruses may have conserved the fundamental function of a regulatory protein during their evolution, whereas RBV has evolved distinctly from the other bornavirus genotypes. 相似文献
17.
Yasunori Akutsu Tsuguaki Kono Masaya Uesato Isamu Hoshino Kentaro Murakami Takeshi Fujishiro Shunsuke Imanishi Satoshi Endo Takeshi Toyozumi Hisahiro Matsubara 《Biological trace element research》2012,150(1-3):109-115
It is known that cisplatin induces the excretion of zinc from the urine and thereby reduces its serum concentration. However, the fluctuation of these trace elements during or after cisplatin-based chemotherapy has not been evaluated. To answer this question, we performed a clinical study in esophageal cancer patients undergoing cisplatin-based chemotherapy. Eighteen patients with esophageal cancer who were not able to swallow food or water orally due to complete stenosis of the esophagus were evaluated. The patients were divided into a control group [total parenteral nutrition (TPN) alone for 28?days, ten cases] and an intervention group (TPN with additional trace elements for 28?days, eight cases). The serum concentrations of zinc, iron, copper, manganese, triiodothyronin (T3), and thyroxin (T4), as alternative indicators of iodine, were measured on days?0, 14, and 28 of treatment, and statistically analyzed on day?28. In the control group, the serum concentration of copper was significantly decreased from 135.4 (day?0) to 122.1???g/ml (day?14), and finally to 110.6???g/ml (day?28, p?=?0.015). The concentration of manganese was also significantly decreased from 1.34 (day?0) to 1.17???g/ml (day?14) and finally to 1.20 (day?28, p?=?0.049). The levels of zinc, iron, T3, and T4 were not significantly changed. In the intervention group, the supplementation with trace elements successfully prevented these decreases in their concentrations. TPN with supplementary trace elements is preferable and recommended for patients who are undergoing chemotherapy in order to maintain the patients?? nutrient homeostasis. 相似文献
18.
Surasak Boonyaritichaikij Kentaro Kuwabara June Nagano Kiyoshi Kobayashi Yasuhiro Koga 《Helicobacter》2009,14(3):202-207
Background: The role of probiotics in the armamentarium remains to be defined. The aims of this study were to investigate whether the long-time administration of Lactobacillus gasseri OLL2716 (LG21) strain can eradicate H. pylori in asymptomatic pre-school children and/or prevent H. pylori infection.
Methods: A total of 440 children, from 5–7 years of age, attending a kindergarten in Thailand were screened by the Helicobacter pylori stool antigen (HpSA) test. Thereafter 132 H. pylori positive and 308 H. pylori negative children were recruited to eradication and randomized prevention arms, respectively. Children in the active and placebo treatment groups received Lactobacillus gasseri OLL2716 (LG21) containing cheese and ordinary cheese, respectively, for 12 months. Eradication was defined as reversion by HpSA at 12 months. Prevention was defined as persistently HpSA negative at 12 months.
Results: Eighty-two of 132 H. pylori positive (62%) completed the eradication arm, of which 24 (29.3%) were negative at 12 months according to the HpSA test. In the randomized prevention arm, 123 of 156 (79%) and 99 of 122 (81%) completed active and placebo arms, respectively, of which 4.1% and 8.1%, respectively, were HpSA positive at 12 months based on a per-protocol analysis ( p = .21).
Conclusion: Further trials are needed. 相似文献
Methods: A total of 440 children, from 5–7 years of age, attending a kindergarten in Thailand were screened by the Helicobacter pylori stool antigen (HpSA) test. Thereafter 132 H. pylori positive and 308 H. pylori negative children were recruited to eradication and randomized prevention arms, respectively. Children in the active and placebo treatment groups received Lactobacillus gasseri OLL2716 (LG21) containing cheese and ordinary cheese, respectively, for 12 months. Eradication was defined as reversion by HpSA at 12 months. Prevention was defined as persistently HpSA negative at 12 months.
Results: Eighty-two of 132 H. pylori positive (62%) completed the eradication arm, of which 24 (29.3%) were negative at 12 months according to the HpSA test. In the randomized prevention arm, 123 of 156 (79%) and 99 of 122 (81%) completed active and placebo arms, respectively, of which 4.1% and 8.1%, respectively, were HpSA positive at 12 months based on a per-protocol analysis ( p = .21).
Conclusion: Further trials are needed. 相似文献
19.
Taku Miyagawa Makoto Honda Minae Kawashima Mihoko Shimada Susumu Tanaka Yutaka Honda Katsushi Tokunaga 《PloS one》2009,4(4)
Background
SNP rs5770917 located between CPT1B and CHKB, and HLA-DRB1*1501-DQB1*0602 haplotype were previously identified as susceptibility loci for narcolepsy with cataplexy. This study was conducted in order to investigate whether these genetic markers are associated with Japanese CNS hypersomnias (essential hypersomnia: EHS) other than narcolepsy with cataplexy.Principal Findings
EHS was significantly associated with SNP rs5770917 (Pallele = 3.6×10−3; OR = 1.56; 95% c.i.: 1.12–2.15) and HLA-DRB1*1501-DQB1*0602 haplotype (P positivity = 9.2×10−11; OR = 3.97; 95% c.i.: 2.55–6.19). No interaction between the two markers (SNP rs5770917 and HLA-DRB1*1501-DQB1*0602 haplotype) was observed in EHS.Conclusion
CPT1B, CHKB and HLA are candidates for susceptibility to CNS hypersomnias (EHS), as well as narcolepsy with cataplexy. 相似文献20.
Sesquiterpenoids from Ferula kuhistanica 总被引:1,自引:0,他引:1
Chen B Teranishi R Kawazoe K Takaishi Y Honda G Itoh M Takeda Y Kodzhimatov OK 《Phytochemistry》2000,54(7):717-722
Methanol extracts of the air-dried roots and stems of Ferula kuhistanica afforded seven daucane-type sesquiterpenes, called kuhistanicaol A-G, together with 13 known daucane esters. Their structures were established on the basis of spectroscopic evidence and the results of chemical reactions. 相似文献