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81.
Fukami H Imajo S Ito A Kakutani S Shibata H Sumida M Tanaka T Niwata S Saitoh M Kiso Y Miyazaki M Okunishi H Urata H Arakawa K 《Drug design and discovery》2000,17(1):69-84
A series of 3-phenylsulfonylquinazoline-2,4-dione derivatives have been synthesized and evaluated for their ability to inhibit human heart chymase. The structure-activity relationship studies on these compounds gave the following results. The phenyl moiety of quinazoline participates in a hydrophobic interaction where an optimum size is required. In this moiety, 7-chloroquinazoline is the best moiety for inhibiting chymase, chymotrypsin and cathepsin G. A 3-phenylsulfonyl moiety substituted with hydrophobic electron-withdrawing groups at the 4-position potentiated the activity. Anthranil moiety also enhanced the activity. Pyridylmethyl and N-pyridylacetamide at the 1-position gave an IC50 in the order of 10(-8)M. Molecular modeling studies on the interaction of 7-chloro-3-(4-chlorophenylsulfonyl) quinazoline-2,4(1H, 3H)-dione (4) with the active site of human heart chymase suggested that the phenyl moiety of quinazoline interacts with the hydrophobic P1 pocket, the 3-phenylsulfonyl moiety resides in the S1'-S2' subsites, the moiety at the 1-position locates in the S2-S3 subsites and the 4-carbonyl and 3-sulfonyl group interact with the oxyanion hole and the His57 side-chain of chymase, respectively. 相似文献
82.
The aim of present study was to evaluate the application of a hydrophilic matrix tablet capable of polyion complex (PIC-tablet) to a controlled-release device for highly water-soluble drugs. The PIC-tablet was prepared from a mixture of dextran sulfate and [2-(diethylamino)ethyl] dextran chloride, and diltiazem hydrochloride was used as a model drug. Release tests revealed that the drug release was sustained even in 50% drug loading and was influenced by ionic strength but not by pH in medium. The drug release mechanism was thus investigated from the viewpoint of drug micelle forming property. The micelle forming ability of diltiazem was examined by the conductivity method, and was found to be influenced by ionic strength but not by pH value in accordance with the release tests. The results suggested that the drug's micelle interacted with the polyionic matrix. Further studies were conducted using metoprolol tartrate and thiamine hydrochloride as cationic drugs and sodium cloxacillin and sodium salicylic acid as anionic ones. The release profiles of the micelle-forming drugs metoprolol tartrate and sodium cloxacillin were also suppressed in spite of different solubility or opposite ionic charge from diltiazem hydrochloride. These findings demonstrated that the PIC-tablet is a promising device for oral controlled release delivery of water-soluble drugs with good micelle-forming ability. 相似文献
83.
Chondroma of the nasal cavity and nasopharynx--a case of chondroma arising from the nasal septum 总被引:1,自引:0,他引:1
Chondromas of the nasal septum are rare. A case of chondroma originating in the left side of the nasal septum is reported. The patient, a 61-year-old female, presented bilateral nasal obstruction, headache, and nasal bleeding. The tumor was removed surgically through the transpalatal approach under general anesthesia. No recurrence was noticed after 6 months follow-up. 相似文献
84.
Minami H Furuhashi M Minami K Miyazaki K Yoshida K Ishikawa K 《Fetal diagnosis and therapy》2008,24(4):357-360
We report a rare case of fetal intraventricular bleeding possibly due to maternal vitamin K deficiency. A 20-year-old woman was admitted to our hospital due to impending premature delivery and loss of dietary intake at 28 weeks of gestation. Her blood examination showed metabolic alkalosis, prolonged prothrombin time, and extremely high level of plasma des-gamma-carboxyprothrombin (protein induced by vitamin K absence, PIVKA-II). Intraventricular hemorrhage was demonstrated by ultrasonography 6 days after admission. She delivered a 2,288-gram girl infant at 40 weeks of gestation. Cranial computerized tomography and magnetic resonance images obtained postnatally demonstrated a reduced cerebral parenchyma adjacent to the interior side of the right lateral ventricle and the deficit of left cerebellum. The infant's head control was insufficient and central impaired hearing was noted at 6 months of life. 相似文献
85.
Y Kajita T Majima M Yoshimura T Hachiya T Miyazaki H Ijichi Y Ochi 《Clinica chimica acta; international journal of clinical chemistry》1978,89(3):485-492
The present paper describes the detection of an autoantibody for glutamic pyruvic transaminase (GPT) in sera of patients with chronic hepatic disorders. In 16 out of 500 patients, the existence of an antibody for pig GPT was demonstrated by the double antibody method, gel filtration and radioimmunoelectrophoresis. The antibody was demonstrated as an immunoglobulin G (IgG) with either polyclonal or monoclonal type (kappa or lambda). The binding portion of IgG with GPT was determined as the fragment Fab, but not Fc of IgG. Because the binding of 125I-pig GPT with the patient's antibody was displaced by human GPT, this antibody may have the characteristic of cross reacting with both pig and human GPT. Although the mechanism of production of the antibody for GPT and the pathological significance of the antibody in chronic hepatic disorders remained obscure, possible inhibition of GPT activity in serum is suggested in the presence of this antibody. 相似文献
86.
Runa Emoto Shoichiro Yatsu Takuma Yoshihara Eiryu Sai Tadashi Miyazaki Taira Yamamoto Atsushi Amano Hiroyuki Daida Katsumi Miyauchi 《Internal medicine (Tokyo, Japan)》2022,61(10):1549
Mid-aortic syndrome (MAS) is a rare vascular disorder that causes refractory hypertension. A 76-year-old woman was hospitalized for acute heart failure (HF) with drug-resistant hypertension; other comorbidities included epigastric artery rupture, old myocardial infarction, an intraventricular thrombus, and a cerebral artery aneurysm. Angiography revealed severe narrowing of the descending aorta, which led to the diagnosis of MAS. Although intensive medical treatment improved her HF, optimal blood pressure (BP) could not be achieved. Percutaneous coronary intervention and surgical bypass for diseased aorta was then performed in two stages, resulting in the achievement of optimal BP and alleviation of HF. 相似文献
87.
Utano Nakamura Taichi Nohmi Riho Sagane Jun Hai Kento Ohbayashi Maiko Miyazaki Atsushi Yamatsu Mujo Kim Yusaku Iwasaki 《Nutrients》2022,14(12)
Gamma-aminobutyric acid (GABA) is present in the mammalian brain as the main inhibitory neurotransmitter and in foods. It is widely used as a supplement that regulates brain function through stress-reducing and sleep-enhancing effects. However, its underlying mechanisms remain poorly understood, as it is reportedly unable to cross the blood–brain barrier. Here, we explored whether a single peroral administration of GABA affects feeding behavior as an evaluation of brain function and the involvement of vagal afferent nerves. Peroral GABA at 20 and 200 mg/kg immediately before refeeding suppressed short-term food intake without aversive behaviors in mice. However, GABA administration 30 min before refeeding demonstrated no effects. A rise in circulating GABA concentrations by the peroral administration of 200 mg/kg GABA was similar to that by the intraperitoneal injection of 20 mg/kg GABA, which did not alter feeding. The feeding suppression by peroral GABA was blunted by the denervation of vagal afferents. Unexpectedly, peroral GABA alone did not alter vagal afferent activities histologically. The coadministration of a liquid diet and GABA potentiated the postprandial activation of vagal afferents, thereby enhancing postprandial satiation. In conclusion, dietary GABA activates vagal afferents in collaboration with meals or meal-evoked factors and regulates brain function including feeding behavior. 相似文献
88.
Possible involvement of IkappaB kinase 2 and MKK7 in osteoclastogenesis induced by receptor activator of nuclear factor kappaB ligand. 总被引:5,自引:0,他引:5
Aiichiro Yamamoto Tsuyoshi Miyazaki Yuho Kadono Hiroshi Takayanagi Toshiki Miura Hiroshi Nishina Toshiaki Katada Kenji Wakabayashi Hiromi Oda Kozo Nakamura Sakae Tanaka 《Journal of bone and mineral research》2002,17(4):612-621
Recent studies have revealed the essential role of the receptor activator of nuclear factor kappaB (NF-kappaB) ligand (RANKL) in osteoclast differentiation and activation. Adenovirus vector could efficiently transduce genes into RAW264.7 cells, which differentiate into osteoclast-like multinucleated cells in the presence of RANKL. The role of NF-kappaB and c-jun N-terminal kinase (JNK) activation in RANKL-induced osteoclast differentiation was investigated using an adenovirus vector carrying the dominant negative 1kappaB kinase 2 gene (AxIKK2DN) or dominant negative MKK7 gene (AxMKK7DN). IKK2DN and MKK7DN overexpression in RAW cells specifically suppressed the NF-kappaB activation and JNK activation in response to RANKL, respectively, without affecting other signaling pathways. Either inhibition of NF-kappaB or JNK pathways dose-dependently inhibited osteoclast formation induced by RANKL. These results suggest that both NF-kappaB and JNK activation are independently required for osteoclast differentiation. 相似文献
89.
Abnormal expression of E-cadherin and beta-catenin may be a molecular marker of submucosal invasion and lymph node metastasis in early gastric cancer 总被引:11,自引:0,他引:11
BACKGROUND: Impaired expression of E-cadherin and alpha- and beta-catenin is frequently observed in several human cancers. The aim of this study was to examine immunohistochemical expression of these adhesion molecules, focusing on early gastric carcinomas, and to investigate differences between differentiated and undifferentiated gastric cancer at the early phase of carcinogenesis. METHODS: Immunohistochemical staining of E-cadherin and alpha- and beta-catenin was performed using specimens from 143 patients with early gastric cancer. RESULTS: Abnormal E-cadherin and beta-catenin staining correlated with depth of tumour invasion in differentiated-type tumours. In contrast, abnormal staining was frequently found even in intramucosal carcinoma of undifferentiated-type tumours, suggesting an apparent difference in the onset of E-cadherin-catenin complex abnormality between the two cancer types. Absent staining of beta-catenin was associated with lymph node metastasis. Multivariate analysis revealed abnormal E-cadherin expression as an independent factor that correlated with submucosal invasion in early gastric cancer. CONCLUSION: Abnormal E-cadherin expression is a possible marker of submucosal invasion in differentiated-type early gastric cancer and absent beta-catenin staining could be used as a predictor of lymph node metastasis in both types. 相似文献
90.
Predictive value of blood flow in the gastric tube in anastomotic insufficiency after thoracic esophagectomy 总被引:5,自引:0,他引:5
Miyazaki T Kuwano H Kato H Yoshikawa M Ojima H Tsukada K 《World journal of surgery》2002,26(11):1319-1323
Anastomotic insufficiency is considered to be one of the most serious complications associated with esophageal reconstruction. The purposes of this study were to identify (1) the relationship between anastomotic insufficiency and tissue blood flow (TBF) in the gastric tube in the perioperative period, and (2) the effects of intravenous prostaglandin E1 (PGE1) on TBF in the gastric tube. The study group consisted of 44 patients who were to undergo esophagectomy for esophageal cancer. Intraoperative and postoperative TBF on the serosal side of the gastric tube were measured by laser-Doppler tissue blood flowmetry. The TBF of the Leakage(+) group (n = 5) was poorer than that of the Leakage(?) group (n = 39) during the intraoperative and postoperative periods. There was a significant difference in TBF between the two groups at postoperative day (POD) 3. There was a tendency in the PGE1(+) group (n = 18) to exhibit richer blood flow through the anastomosis than the PGE1(?) group (n = 26), intraoperatively, but the difference was not significant. Two of five Leakage(+) cases were also in the PGE1(+) group. There was no relationship between intraoperative medication with PGE1 and incidence of leakage. The TBF of three-field lymph node dissection and reconstruction of the retrosternal route group (n = 21) was poorer than that of the two-field lymph-node dissection and reconstruction of the posterior mediastinal route group (n = 23). The TBF in the gastric tube after esophagectomy may be a predictor of anastomotic insufficiency. However, PGE1 treatment in the intraoperative period alone is not effective in preventing anastomotic insufficiency. 相似文献