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21.
Akira Nakamura Akira Imamiya Yuichiro Ikegami Fei Rao Harumi Yuguchi Yasuyoshi Miki Tomohiro Maegawa 《RSC advances》2022,12(47):30426
We developed a method for highly selective synthesis of two benzofuran isomers, by rearranging and subsequently transforming 2-hydroxychalcones. Depending on the reaction conditions, synthesis of 3-formylbenzofurans, unconventional products, and 3-acylbenzofurans was achieved through cyclized 2,3-dihydrobenzofurans obtained from the rearranged products. The facile synthesis of 3-formylbenzofurans facilitated synthesis of the natural product, puerariafuran, from the corresponding chalcone.A method for the highly selective synthesis of two benzofuran isomers, 3-formylbenzofurans and 3-acylbenzofurans, by rearranging and subsequently transforming 2-hydroxychalcones has been developed. 相似文献
22.
目的测量鼻息肉(nasal polyps,NP)组织细胞核中活化的糖皮质激素受体(glucocorticoid receptor,GR)蛋白水平。方法应用ELlSA方法定量测定NP组织细胞核内活化的GR的蛋白水平。NP组织从不并发支气管哮喘和并发支气管哮喘的(chronic rhinosinusitis,CRS)伴NP患者中取得。在后者,NP组织在(glucocorticoid,Glu)治疗前和治疗后分次取得。结果不并发支气管哮喘和并发支气管哮喘Glu治疗前的CRS伴NP患者中,活化GR蛋白水平没有显著性差异。Glu治疗后,GIu蛋白水平较治疗前显著增高。结论Glu上调NP组织细胞核内活化的GR蛋白水平,这对于发挥Glu的抗炎作用至关重要。 相似文献
23.
24.
Watanabe N Arai H Nishihara Y Taniguchi M Watanabe N Hunter T Osada H 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(13):4419-4424
Wee1, the Cdc2 inhibitory kinase, needs to be down-regulated at the onset of mitosis to ensure rapid activation of Cdc2. Previously, we have shown that human somatic Wee1 (Wee1A) is down-regulated both by protein phosphorylation and degradation, but the underlying mechanisms had not been elucidated. In the present study, we have identified the beta-transducin repeat-containing protein 1/2 (beta-TrCP1/2) F-box protein-containing SKP1/Cul1/F-box protein (SCF) complex (SCF(beta-TrCP1/2)) as an E3 ubiquitin ligase for Wee1A ubiquitination. Although Wee1A lacks a consensus DS(p)GXXS(p) phospho-dependent binding motif for beta-TrCP, recognition of Wee1A by beta-TrCP depended on phosphorylation, and two serine residues in Wee1A, S53 and S123, were found to be the most important phosphorylation sites for beta-TrCP recognition. We have found also that the major M-phase kinases polo-like kinase 1 (Plk1) and Cdc2 are responsible for the phosphorylation of S53 and S123, respectively, and that in each case phosphorylation generates an unconventional phospho-degron (signal for degradation) that can be recognized by beta-TrCP. Phosphorylation of Wee1A by these kinases cooperatively stimulated the recognition and ubiquitination of Wee1A by SCF(beta-TrCP1/2) in vitro. Mutation of these residues or depletion of beta-TrCP by small-interfering RNA treatment increased the stability of Wee1A in HeLa cells. Moreover, our analysis indicates that beta-TrCP-dependent degradation of Wee1A is important for the normal onset of M-phase in vivo. These results also establish the existence of a feedback loop between Cdc2 and Wee1A in somatic cells that depends on ubiquitination and protein degradation and ensures the rapid activation of Cdc2 when cells are ready to divide. 相似文献
25.
Simulated body surface potential maps (SBSPM) with isotropic and anisotropic heart models were compared to investigate the effect of myocardial anisotropy on body surface electrocardiograms at a whole heart level. Rotative fiber orientations of total 90° was incorporated into an isotropic heart model. The anisotropy of conduction velocity and intracellular electric conductivity was included in the simulation. SBSPM based on epicardial, intramural, and endocardial stimulation show high correlation with fiber orientations. On the other hand, the anisotropy cannot be distinguished from the SBSPM in the simulation of normal heart model. 相似文献
26.
Katsuhiko Hatake Ichiro Wakabayashi Eizo Kakishita Tadaaki Taniguchi Harumi Ouchi Shigeru Hishida 《Alcoholism, clinical and experimental research》1991,15(1):112-115
Rats were maintained on liquid diets containing ethanol (35% of total calories) or an equicaloric volume of sucrose instead of ethanol for 10 wk. Vascular strips of isolated rat aortas were mounted in organ chambers to record isometric tension. Ethanol in vitro inhibited the endothelium-dependent relaxation responses to acetylcholine and ATP in both pair-fed control and ethanol-fed rats. The inhibitory effect of ethanol was greater in the pair-fed rats. In addition, the magnitudes of these relaxation responses in the absence of ethanol in vitro in pair-fed rats were similar to those in the presence of ethanol in ethanol-fed rats. In the absence of ethanol in vitro, the relaxations in response to acetylcholine and ATP in the ethanol-fed rats were greater than in the pair-fed rats. These results suggest that chronic ethanol consumption can induce tolerance to ethanol-induced inhibition of endothelium-dependent relaxation responses to acetylcholine and ATP, and that the relaxations can become adapted to the presence of plasma levels of ethanol, which may inhibit the relaxation in vivo. The augmented relaxation in the ethanol-fed rats may result from the mechanism causing tolerance to the inhibitory effect of ethanol. 相似文献
27.
The initial portion of the QRS complex in WPW syndrome might be represented by a single dipole, since the delta wave corresponds to the localized ventricular activation propagated over the accessory atrioventricular pathway. In order to examine whether the site of the accessory pathway in WPW syndrome could be localized by an equivalent dipole method, the dipole positions during the delta wave were determined in 30 patients using a three dimensional model of the torso and were then compared with the sites of accessory pathways localized by body surface maps. The single dipole approximation during the delta wave appeared to be appropriate since the index of the nondipolarity of the potentials was as low as 28% on average. The dipole positions determined on the atrioventricular ring during the delta wave were compatible with the sites of accessory pathways localized by body surface maps in 22 of the 30 patients. The dipole positions were adjacent to the sites of accessory pathways in 7 of the remaining 8 patients. Thus the equivalent dipole method might be an additional noninvasive tool to determine the site of the accessory pathway in WPW syndrome. 相似文献
28.
Harumi Koyama Michiko Kakami Makiko Kawamura Reiko Tokuda Yasuto Kondo Ikuya Tsuge Kazue Yamada Toshitaka Yasuda Atsuo Urisu 《Allergology international》2006,55(3):311-316
BACKGROUND: Hypersensitivity reactions to fish are a common food allergy, but IgE-binding activity to fish species have not been fully elucidated. The aim of this study was to identify fish with high binding activity to IgE in sera from Japanese fish-hypersensitive individuals. METHODS: 38 children with a history of at least one episode of hypersensitivity after ingestion of fish were enrolled and 34 children with no history of reactions and negative IgE results for at least five kinds of fish antigen were included as controls. Using a radioallergosorbent test, we examined IgE-binding to each fish species using sera from fish-hypersensitive subjects. Fish were then graded according to IgE-binding activity. RESULTS: Many fish species, including red salmon, silver salmon, yellowfin tuna, big eyed tuna, Atlantic tuna, saurel, skipper, yellowtail, Japanese sardine, bonita and mackerel had high IgE-binding activity. All of these fish are abundantly consumed in Japan. The hypersensitivity reactions experienced by many subjects occurred after ingestion of species with high IgE-binding activity. Only halibut (Osteichthyes) and sharks (Chondrichthyes) had low IgE-binding activity. CONCLUSIONS: A correlation was observed between IgE levels and expression of symptoms after fish ingestion. High consumption of salmon, tuna, scad (including saurel), skipper, yellowtail, sardine, bonita and mackerel in Japan might be the cause of the high IgE-binding activity of these species. The grades of fish species consumed widely in Japan are likely to be useful for nutritional instruction of fish-allergic patients. 相似文献
29.
Katsura Y Suzukawa K Kojima H Yoshida C Shimizu S Mukai H Hasegawa Y Imagawa S Mori N Nagasawa T 《International journal of hematology》2003,77(3):282-285
The case of a 49-year-old man with peripheral T-cell lymphoma arising in Behçet disease (BD) is reported. A diagnosis of incomplete BD was made, and the patient was treated with immunosuppressive agents for 9 months. A left perirenal mass emerged, and a computed tomography-guided needle biopsy of the tumor revealed the infiltration of small- and medium-sized lymphoma cells.The cells were positive for CD3, CD8, CD45RO, CD43, granzyme B, and T-cell intracellular antigen-1.A diagnosis of non-Hodgkin’s lymphoma (diffuse medium, T-cell) was made.A left orbital mass also appeared. Standard combination chemotherapy diminished the perirenal and orbital lesions.Lymphoma cell infiltration in the esophagus was detected after chemotherapy, and the patient died of massive bleeding from the gastrointestinal tract. Non-Hodgkin’s lymphoma is rarely associated with BD, and only 7 cases have been reported in the literature.We have summarized the published case reports of malignant lymphoma arising in BD.To our knowledge, this case report is the first to describe cytotoxic T-cell lymphoma arising in Behçet disease. 相似文献
30.
Takeshi Saraya Michiaki Mikoshiba Harumi Kamiyama Masakazu Yoshizumi Shigeru Tsuchida Hiroyuki Tsukagoshi Taisei Ishioka Miho Terada Eiichi Tanabe Chizuko Tomioka Haruyuki Ishii Hirokazu Kimura Kunihisa Kozawa Tetsuo Shiohara Hajime Takizawa Hajime Goto 《Journal of clinical microbiology》2013,51(6):1979-1982
The present case provides direct evidence of human herpesvirus 6 reactivation in resected lymph node tissue in a patient with drug-induced hypersensitivity syndrome. This case clearly demonstrates that appropriate pathological evaluation of lymphadenopathy for drug-induced hypersensitivity syndrome, which mimics malignant lymphoma in clinical, radiological, and pathological findings, is required. 相似文献