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71.
J R Arden O Nagata M S Shockley M Philip J Lameh W Sadée 《Biochemical and biophysical research communications》1992,188(3):1111-1115
We measured dose-response curves for carbachol stimulation of phosphatidyl inositol (PI) turnover with mutants of the Hm1 muscarinic cholinergic receptor having various deletions from amino acids 219 to 358 of the large third intracellular (i3) loop (208 to 366). These deletions had only small or no effects on the ability of Hm1 transfected into HEK 293 cells to stimulate PI turnover. This result indicates that only small regions of 9 to 11 amino acids adjacent to trans-membrane domains (TMDs) 5 and 6 can be directly involved in G protein coupling. Point mutations were constructed to test the role of charged amino acids in these junctions. A triple point mutation of Hm1 (E214 A/ E216K/ E221 K), which mimics the charge distribution in Hm2 (negatively coupled to cAMP) over the first 14 amino acids of i3, and a double point mutation in the N terminal junction, K359A/K361A, both failed to affect carbachol stimulated PI turnover. Therefore, charge distribution in the loop junctions appears to play a minor role in G protein coupling of Hm1 in HEK 293 cells. 相似文献
72.
Sakamoto Hideo Kuzuya Hiroshi Tamaru Masao Sugimoto Sukeo Shimizu Jun Fukushima Minoru Yazaki Takehiko Yamazaki Toshio Nagata Yutaka 《Neurochemical research》1998,23(1):115-120
The NGF content in each region of the brain of four-week-old rats was ranked in the decreasing order of cerebral cortex, hippocampus, cerebellum, midbrain/diencephalon, and pons/medulla ob-longata, and the NGF concentration, in the decreasing order of hippocampus, cerebral cortex, cerebellum, midbrain/diencephalon, and pons/medulla oblongata in both AFD and SFD groups. The NGF content and concentration in the cerebral cortex were about the same value at each age between those in the AFD and SFD groups. Those in the hippocampus were a little higher in the SFD group than in the AFD group at the ages of three and four weeks, unlike those in the other regions, where the values for the cerebellum, midbrain/diencephalon and pons/medulla oblongata tended to be somewhat higher in the AFD group than in the SFD group. The NGF concentrations in the hippocampus and cerebral cortex increased with growth: the concentration in the hippocampus at four weeks of age was about 4-fold of that at one week in the AFD group and about 5.7-fold of that at one week in the SFD group; and likewise the concentration in the cerebral cortex at four weeks of age was about 5.3-fold in the AFD group and about 7-fold in the SFD group. The NGF concentrations in the cerebellum decreased, and those in midbrain/diencephalon and pons/medulla oblongata hardly changed with growth in either AFD or SFD group. From these results NGF may have stronger implications for the neuronal growth in the hippocampus compared with those in the lower brain regions of the SFD rats. 相似文献
73.
Assignment of the human granulocyte colony-stimulating factor receptor gene (CSF3R) to chromosome 1 at region p35-p34.3. 总被引:2,自引:0,他引:2
The gene for the granulocyte colony-stimulating factor (G-CSF) receptor (CSF3R) was localized on the p35-p34.3 region of human chromosome 1 by in situ hybridization using human G-CSF receptor cDNA as the probe. Polymerase chain reaction using oligonucleotides specific for the human CSF3R produced a specifically amplified DNA fragment with DNA from mouse A9 cells that contained human chromosome 1 but not other human chromosomes. Localization of the CSF3R on chromosome 1 was further confirmed by the spot-blot hybridization of sorted human chromosomes. 相似文献
74.
Hisashi Mizutani Hideaki Sugawara Ashley M. Buckle Takeshi Sangawa Ken-ichi Miyazono Jun Ohtsuka Koji Nagata Tomoki Shojima Shohei Nosaki Yuqun Xu Delong Wang Xiao Hu Masaru Tanokura Kei Yura 《BMC structural biology》2017,17(1):4
Background
More than 7000 papers related to “protein refolding” have been published to date, with approximately 300 reports each year during the last decade. Whilst some of these papers provide experimental protocols for protein refolding, a survey in the structural life science communities showed a necessity for a comprehensive database for refolding techniques. We therefore have developed a new resource – “REFOLDdb” that collects refolding techniques into a single, searchable repository to help researchers develop refolding protocols for proteins of interest.Results
We based our resource on the existing REFOLD database, which has not been updated since 2009. We redesigned the data format to be more concise, allowing consistent representations among data entries compared with the original REFOLD database. The remodeled data architecture enhances the search efficiency and improves the sustainability of the database. After an exhaustive literature search we added experimental refolding protocols from reports published 2009 to early 2017. In addition to this new data, we fully converted and integrated existing REFOLD data into our new resource. REFOLDdb contains 1877 entries as of March 17th, 2017, and is freely available at http://p4d-info.nig.ac.jp/refolddb/.Conclusion
REFOLDdb is a unique database for the life sciences research community, providing annotated information for designing new refolding protocols and customizing existing methodologies. We envisage that this resource will find wide utility across broad disciplines that rely on the production of pure, active, recombinant proteins. Furthermore, the database also provides a useful overview of the recent trends and statistics in refolding technology development.75.
Yoshikazu Nagata Tadashi Tetsukawa Takanori Kobayashi Ken-ichi Numachi 《Ichthyological Research》1996,43(2):117-124
Eleven populations of the rosy bitterling,Rhodeus ocellatus, from different localities in Japan, were genetically compared at 16 protein-coding loci using starch-gel electrophoresis.
Two loci,Ldh-2 andPgdh, were demonstrated as diagnostic markers for the identification of two subspecies;R. ocellatus kurumeus, which is native to Japan, andR. ocellatus ocellatus, which was introduced from China. The two subspecies were distinguished by the complete substitution of different alleles
between them. Population ofR. ocellatus kurumeus occurring in Yao City, Osaka, and in Kanzaki, Saga Prefecture were genetically closely related to each other (genetic distance:
D=0.056) but distantly so toR. ocellatus ocellatus from Saitama Prefecture (D=0.202 or 0.265). Electrophoretic analyses also elucidated the existence of hybrid populations
of the two subspecies. The populations ofR. ocellatus kurumeus in Yao City had lower genetic variability and a lower incidence of white coloration on the ventral fins than populations
of the same in Saga Prefecture. The present study strongly implies that the introduction of the foreign freshwater fishes
with subspecific differentiation, into the original range of indigenous subspecies, should be averted not to bring the genetic
pollution. 相似文献
76.
Masuda K Yutani C Akutagawa K Yamamoto S Hatsuyama H Ishibashi-Ueda H Imakita M Manaka H Takahashi J Nagata I 《Acta cytologica》2000,44(6):1050-1058
BACKGROUND: Primitive neuroectodermal tumors (PNETs) are very rare. Malignant tumors of the cerebrum in young individuals are composed predominantly of undifferentiated cells, with moderate differentiation along either neuronal or glial lines. To our knowledge, cerebral PNETs in adults are extraordinarily rare and have been reported in only 11 cases, with little cytologic documentation in the literature. The cytopathologic, immunohistochemical and ultrastructural features of cerebral PNET arising in an adult male are presented. CASE: A cystic tumor, on computed tomography and magnetic resonance imaging, arose from the left frontal lobe in a 39-year-old man and contained histopathologic features of PNET. Specimens obtained from surgery revealed the presence of an undifferentiated type of PNET with moderate neuronal and glial differentiation and mild characteristic findings of peripheral PNET. The cytologic and histologic specimens showed evidence of a scattered pattern of blastic and undifferentiated tumor cells and a neural arrangement with Homer-Wright-like rosettes. Immunohistochemically, the tumor cells were glial fibrillary acidic protein, neuron-specific enolase, synaptophysin and CD-99 positive and epithelial membrane antigen, S-100 protein and vimentin negative. Ultrastructurally, neither microtubular structures nor intermediate filaments, except neurosecretory granules, were found in the tumor cells. CONCLUSION: Both immunohistochemical and ultrastructural studies on cytologic and histologic slides were important for the diagnosis of PNET because of establishing not only undifferentiated tumor cells but also neural and glial differentiation. 相似文献
77.
The endoplasmic reticulum (ER) uses an elaborate surveillance system called the ER quality control (ERQC) system. The ERQC facilitates folding and modification of secretory and membrane proteins and eliminates terminally misfolded polypeptides through ER-associated degradation (ERAD) or autophagic degradation. This mechanism of ER protein surveillance is closely linked to redox and calcium homeostasis in the ER, whose balance is presumed to be regulated by a specific cellular compartment. The potential to modulate proteostasis and metabolism with chemical compounds or targeted siRNAs may offer an ideal option for the treatment of disease. 相似文献
78.
Hiroki Tanabe Keiichi Yoshino Katsuyoshi Ando Yoshiki Nomura Katsuhisa Ohta Kiichi Satoh Eiichiro Ichiishi Akiei Ishizuka Takaaki Otake Yutaka Kohgo Mikihiro Fujiya Toshikatsu Okumura 《Annals of clinical microbiology and antimicrobials》2018,17(1):29
Background
All Helicobacter pylori-infected patients are recommended for eradication with an appropriate regimen in each geographic area. The choice of the therapy is somewhat dependent on the antimicrobial susceptibility. The rate of clarithromycin resistance has been increasing and is associated with failure; thus, susceptibility testing is recommended before triple therapy with clarithromycin. However, antimicrobial susceptibility testing is not yet clinically available and an alternative newly developed acid inhibitor vonoprazan is used for triple therapy in Japan. The aim of this study was to determine whether vonoprazan-based triple therapy is plausible treatment in H. pylori eradication.Methods
A retrospective observational study of H. pylori eradication was conducted in a single institute. The patients who requested antimicrobial susceptibility testing were treated with susceptibility-guided proton pump inhibitor-based triple therapy in International University of Health and Welfare Hospital from 2013 to 2016. Other patients were treated with empirical treatment with a proton pump inhibitor. From 2015 to 2016, vonoprazan-based triple treatment (vonoprazan, 20 mg; amoxicillin, 750 mg; and clarithromycin, 200 or 400 mg, b.i.d.) was conducted, and its effectiveness was compared with susceptibility-guided proton pump inhibitor-based triple therapy. We also investigated the improvement in eradication rate when antimicrobial susceptibility testing was performed, and compared the outcomes of vonoprazan-based and proton pump inhibitor-based empirical therapy.Results
A total of 1355 patients who received first-line eradication treatment were enrolled in the present study. The eradication rates of the empirical proton pump inhibitor-based therapy and the vonoprazan-based therapy group in a per-protocol analysis were 86.3% (95% CI 83.8–88.8) and 97.4% (95% CI 95.7–99.1), respectively. In 212 patients who received antimicrobial susceptibility testing, the rate of clarithromycin resistant was 23.5% and the eradication rate in susceptibility-guided treatment was 95.7% (95% CI 92.9–98.4). The difference between susceptibility-guided and vonoprazan-based therapy was ??1.7% (95% CI ??4.9 to 1.5%), and the non-inferiority of vonoprazan-based triple therapy was confirmed.Conclusions
Vonoprazan-based triple therapy was effective as susceptibility-guided triple therapy for H. pylori eradication. An empirical triple therapy with vonoprazan is preferable even in area with high rates of clarithromycin-resistance.Trial registration The study was retrospectively registered in University Hospital Medical Information Network (UMIN000032351)79.
Taichiro Miyake Kosuke Soda Yasushi Itoh Yoshihiro Sakoda Hirohito Ishigaki Tomoya Nagata Hideaki Ishida Misako Nakayama Hiroichi Ozaki Hideaki Tsuchiya Ryuzo Torii Hiroshi Kida & Kazumasa Ogasawara 《Journal of medical primatology》2010,39(1):58-70
Background Highly pathogenic avian influenza virus (HPAIV) infection has a high mortality rate in humans. Secondary bacterial pneumonia with HPAIV infection has not been reported in human patients, whereas seasonal influenza viruses sometimes enhance bacterial pneumonia, resulting in substantial morbidity and mortality. Therefore, if HPAIV infection were accompanied by bacterial infection, an increase in mortality would be expected. We examined whether a vaccine against HPAIV prevents severe morbidity caused by mixed infection with HPAIV and bacteria.
Methods H7N7 subtype of HPAIV and Streptococcus pneumoniae were inoculated into cynomolgus macaques with or without vaccination of inactivated whole virus particles .
Results Vaccination against H7N7 HPAIV decreased morbidity caused by HPAIV and pneumonia caused by S. pneumoniae . Bacterial replication in lungs was decreased by vaccination against HPAIV, although the reduction in bacterial colonies was not significant.
Conclusions Vaccination against HPAIV reduces pneumonia caused by bacterial superinfection and may improve prognosis of HPAIV-infected patients. 相似文献
Methods H7N7 subtype of HPAIV and Streptococcus pneumoniae were inoculated into cynomolgus macaques with or without vaccination of inactivated whole virus particles .
Results Vaccination against H7N7 HPAIV decreased morbidity caused by HPAIV and pneumonia caused by S. pneumoniae . Bacterial replication in lungs was decreased by vaccination against HPAIV, although the reduction in bacterial colonies was not significant.
Conclusions Vaccination against HPAIV reduces pneumonia caused by bacterial superinfection and may improve prognosis of HPAIV-infected patients. 相似文献
80.