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81.
82.
Fujii H Osa Y Ishihara M Hanamura S Nemoto T Nakajima M Hasebe K Mochizuki H Nagase H 《Bioorganic & medicinal chemistry letters》2008,18(18):4978-4981
Selective ring opening reaction of the N-cyclopropylmethyl group in naltrexone (1d) was effected in the presence of platinum (IV) oxide and hydrobromic acid under a hydrogen atmosphere at rt to selectively afford N-isobutyl derivative 10. The binding affinity of N-i-Bu derivative 10 for opioid receptors was 11-17 times less than that of the corresponding N-CPM compound, naltrexone (1d). However, compound 10 showed dose-dependent analgesic effects. Contrary to expectations based on previous structure-activity relationship studies for a series of N-substituted naltrexone derivatives that compound 10 would be an opioid antagonist, 10 showed dose-dependent analgesia in the mouse acetic acid writhing test (ED(50): 5.05 mg/kg, sc), indicating it was an opioid agonist. This finding may have a great influence on the drug design of opioid agonists. 相似文献
83.
84.
Moriya K Suzuki M Watanabe Y Takahashi T Aoki Y Uchiyama T Kumaki S Sasahara Y Minegishi M Kure S Tsuchiya S Sugamura K Ishii N 《PloS one》2012,7(6):e37892
Mixed-lineage-leukemia (MLL) fusion oncogenes are intimately involved in acute leukemia and secondary therapy-related acute leukemia. To understand MLL-rearranged leukemia, several murine models for this disease have been established. However, the mouse leukemia derived from mouse hematopoietic stem cells (HSCs) may not be fully comparable with human leukemia. Here we developed a humanized mouse model for human leukemia by transplanting human cord blood-derived HSCs transduced with an MLL-AF10 oncogene into a supra-immunodeficient mouse strain, NOD/Shi-scid, IL-2Rγ(-/-) (NOG) mice. Injection of the MLL-AF10-transduced HSCs into the liver of NOG mice enhanced multilineage hematopoiesis, but did not induce leukemia. Because active mutations in ras genes are often found in MLL-related leukemia, we next transduced the gene for a constitutively active form of K-ras along with the MLL-AF10 oncogene. Eight weeks after transplantation, all the recipient mice had developed acute monoblastic leukemia (the M5 phenotype in French-American-British classification). We thus successfully established a human MLL-rearranged leukemia that was derived in vivo from human HSCs. In addition, since the enforced expression of the mutant K-ras alone was insufficient to induce leukemia, the present model may also be a useful experimental platform for the multi-step leukemogenesis model of human leukemia. 相似文献
85.
Ueki Y Shoji M Suto A Tanabe T Okimura Y Kikuchi Y Saito N Sano D Omura T 《Applied and environmental microbiology》2007,73(17):5698-5701
The fate of calicivirus in oysters in a 10-day depuration was assessed. The norovirus gene was persistently detected from artificially contaminated oysters during the depuration, whereas feline calicivirus in oysters was promptly eliminated. The prolonged observation of norovirus in oysters implies the existence of a selective retention mechanism for norovirus within oysters. 相似文献
86.
Purification,characterization and gene cloning of isoeugenol-degrading enzyme from <Emphasis Type="Italic">Pseudomonas putida</Emphasis> IE27 总被引:1,自引:0,他引:1
An isoeugenol-degrading enzyme was purified to homogeneity from Pseudomonas putida IE27, an isoeugenol-assimilating bacterium. The purified enzyme was a 55 kDa monomer and catalyzed the initial step of isoeugenol
degradation, the oxidative cleavage of the side chain double-bond of isoeugenol, to form vanillin. Another reaction product
of isoeugenol degradation besides vanillin was identified to be acetaldehyde. The values of Km and k
cat for isoeugenol were 175 μM and 5.18 s–1, respectively. The purified enzyme catalyzed the incorporation of an oxygen atom from either molecular oxygen or water into
vanillin, suggesting that the isoeugenol-degrading enzyme is a kind of monooxygenase. The gene encoding the isoeugenol-degrading
enzyme and its flanking regions were isolated from P. putida IE27. The amino acid sequence of the enzyme was similar to those of lignostilbene-α,β-dioxygenases, carotenoid monooxygenases
and 9-cis-epoxycarotenoid dioxygenases. 相似文献
87.
Naoko Aizawa Hiroshi Kunikata Fumihiko Nitta Yukihiro Shiga Kazuko Omodaka Satoru Tsuda Toru Nakazawa 《PloS one》2016,11(2)
Purpose
To investigate the relationship between various characteristics of a normal population and laser speckle flowgraphy (LSFG) measurements of mean blur rate (MBR) in the optic nerve head (ONH).Methods
A total of 189 eyes of 189 normal subjects (93 male, 96 female, mean age 45 ± 14 years old, age range: 20–72) without any history of hypertension, hyperlipidemia or diabetes were enrolled. ONH microcirculation was measured with LSFG and overall MBR (MA), vessel-area MBR (MV), and tissue-area MBR (MT) were derived from these measurements. The statistical association of these measurements with characteristics such as sex, age, intraocular pressure (IOP) and systolic blood pressure (SBP) was then determined.Results
There was a trend towards decreased IOP and MV and increased SBP with age (P = 0.002, P = 0.035, and P = 0.006, respectively). Furthermore, IOP, MV and SBP were correlated with age (r = -0.23, P = 0.011; r = -0.24, P < 0.001; and r = 0.30, P < 0.001, respectively). Separate multiple regression analyses of independent contributing factors revealed that sex and IOP contributed to MA (P < 0.001 and P = 0.002, respectively), sex, IOP, and age contributed to MV (P < 0.001, P = 0.003, and P = 0.024, respectively), while only IOP contributed to MT (P = 0.003).Conclusion
In a normal population, MBR was affected by IOP in both the large vessel and capillary areas of the ONH, but not by SBP. MV was also affected by age and sex, while MT was stable independent of age or sex. 相似文献88.
Norihide Hinomoto Masahiko Muraji Takashi Noda Toru Shimizu Kenjiro Kawasaki 《Biological Control》2004,31(3):642
We developed multiplex polymerase chain reaction methods to identify five Orius (Heteroptera: Anthocoridae) species that occur commonly in Japan: Orius sauteri, Orius minutus, Orius strigicollis, Orius nagaii, and Orius tantillus. The method amplified internal transcribed spacer 1 of the nuclear ribosomal DNA by using five primers simultaneously and produced species-specific banding patterns upon agarose gel electrophoresis. Reliability of the method was tested for 350 individuals of 23 strains, and consistent results were obtained. Dichotomous keys are also provided for easy and quick species identification. 相似文献
89.
The BTB-kelch protein KLHL6 is involved in B-lymphocyte antigen receptor signaling and germinal center formation 下载免费PDF全文
Kroll J Shi X Caprioli A Liu HH Waskow C Lin KM Miyazaki T Rodewald HR Sato TN 《Molecular and cellular biology》2005,25(19):8531-8540
BTB-kelch proteins can elicit diverse biological functions but very little is known about the physiological role of these proteins in vivo. Kelch-like protein 6 (KLHL6) is a BTB-kelch protein with a lymphoid tissue-restricted expression pattern. In the B-lymphocyte lineage, KLHL6 is expressed throughout ontogeny, and KLHL6 expression is strongly upregulated in germinal center (GC) B cells. To analyze the role of KLHL6 in vivo, we have generated mouse mutants of KLHL6. Development of pro- and pre-B cells was normal but numbers of subsequent stages, transitional 1 and 2, and mature B cells were reduced in KLHL6-deficient mice. The antigen-dependent GC reaction was blunted (smaller GCs, reduced B-cell expansion, and reduced memory antibody response) in the absence of KLHL6. Comparison of mutants with global loss of KLHL6 to mutants lacking KLHL6 specifically in B cells demonstrated a B-cell-intrinsic requirement for KLHL6 expression. Finally, B-cell antigen receptor (BCR) cross-linking was less sensitive in KLHL6-deficient B cells compared to wild-type B cells as measured by proliferation, Ca2+ response, and activation of phospholipase Cgamma2. Our results strongly point to a role for KLHL6 in BCR signal transduction and formation of the full germinal center response. 相似文献
90.
Mayumi MoriHiroki Kimura Yoshihiro IwamuraSatoko Arai Toru Miyazaki 《FEBS letters》2012,586(20):3569-3574
The mouse macrophage-derived apoptosis inhibitor of macrophage (AIM), which is incorporated into adipocytes and induces lipolysis by suppressing fatty acid synthase (FAS) activity, possesses three potential N-glycosylation sites. Inactivation of N-glycosylation sites revealed that mouse AIM contains two N-glycans in the first and second scavenger receptor cysteine-rich domains, and that depletion of N-glycans decreased AIM secretion from producing cells. Interestingly, the lack of N-glycans increased AIM lipolytic activity through enhancing AIM incorporation into adipocytes. Although human AIM contains no N-glycan, attachment of N-glycans increased AIM secretion. Thus, the N-glycosylation plays important roles in the secretion and lipolytic function of AIM.