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51.
52.
Glucocorticoid receptor enhancement of pregnane X receptor-mediated CYP2B6 regulation in primary human hepatocytes. 总被引:2,自引:0,他引:2
Hongbing Wang Stephanie R Faucette Darryl Gilbert Summer L Jolley Tatsuya Sueyoshi Masahiko Negishi Edward L LeCluyse 《Drug metabolism and disposition》2003,31(5):620-630
Although the glucocorticoid receptor (GR) facilitates the xenobiotic-induced expression of CYP2B in rodents, its role in the regulation of human CYP2B6 is unclear. In this report, the role of human GR in the regulation of CYP2B6 was evaluated using primary human hepatocytes and transfection assays with Huh7 cells. CYP2B6 expression was not induced in primary hepatocytes treated with dexamethasone (DEX) concentrations (0.01-1 microM) known to activate GR. In contrast, treatment with 0.1 microM DEX enhanced CYP2B6 induction by different pregnane X receptor (PXR) activators, including rifampin, phenytoin, clotrimazole, and phenobarbital. In Huh7 cells, cotransfection of human (h)GR and hPXR with CYP2B6-phenobarbital-responsive enhancer module (PBREM) reporter constructs revealed that all hPXR ligands induce CYP2B6 reporter gene activity, and this ligand-dependent activation is greatly enhanced by activated hGR. CYP2B6 reporter gene expression was not induced in the presence of hPXR ligands when hGR alone was cotransfected with CYP2B6 reporter construct. In hGR and human constitutive androstane receptor (hCAR) cotransfection assays, activated hGR increased the constitutive activation of PBREM reporter constructs by hCAR in the absence of inducers. In the presence of activated hGR and known inducers of CYP2B6, only PB treatment caused a further 2-fold activation of hCAR compared with control. These studies show that hGR is involved synergistically in the xenobiotic-responsive regulation of human CYP2B6 by hPXR and hCAR. Moreover, the results suggest that the GR-enhanced expression of CYP2B6 is mediated through an indirect mechanism that does not require increased expression of nuclear receptor. 相似文献
53.
Tatsuya Nomura Tokihiro Yoshikawa Hideo Kato Keiya Nikkuni Koichi Sasaki Yoshio Shirai Katsuyoshi Hatakeyama 《Surgery today》1997,27(4):334-336
A case of early gastric cancer, limited to submucosal layer, which was manifested as cerebral metastasis is presented herein. A 47-year-old man was admitted to Nagaoka Chuo General Hospital with convulsions and a disturbance in consciousness, where a computed tomography (CT) scan revealed a cerebral tumor in the left temporal lobe. The resected tumor was identified as a metastatic adenocarcinoma. Further investigation revealed gastric cancer involving the posterior wall of the cardia. At laparotomy, multiple and small metastases of the liver and a jejunal metastasis were found, and a palliative total gastrectomy was performed. The surgical specimen revealed a protruding, poorly differentiated medullary adenocarcinoma, with invasion of the submucosal layer. The patient died 4 months after undergoing the laparotomy. This case report is presented to make clinicians aware of the possibility that early gastric cancers may present as brain metastasis. 相似文献
54.
55.
Akira Sezai Motomi Shiono Tatsuya Inoue Mitsumasa Hata Mitsuru Iida Tetsuya Niino Akira Saito Tsutomu Hattori Shinji Wakui Masao Soeda Nanao Negishi Yukiyasu Sezai 《Annals of thoracic and cardiovascular surgery》2004,10(3):191-194
The patient was a 48-year-old male who was diagnosed with unstable angina. He had worsening cardiogenic shock during coronary angiography. Emergency coronary artery bypass grafting (CABG) was performed. He had a methicillin-resistant Staphylococcus aureus (MRSA) mediastinitis on day 22 after CABG. Drains were placed in the anterior mediastinum, left thoracic cavity, and abscess cavity, and another drain was placed in the mediastinal space for continuous cleansing with povidone iodine, oxydol. For antibiotics, teicoplanin (TEIC) was administered intravenously and to the local site via the cleansing drain for about one month. No MRSA was detected by culture in discharges from the mediastinal drain. Inflammatory findings were improved, and the patient was discharged and resumed everyday life without recurrence of inflammation as of eight months. Although the number of cases of MRSA mediastinitis is small and accumulation of cases is necessary to investigate therapeutic methods and selection of antibiotics, our department will select closed continuous cleansing and TEIC for antibiotics as the first choice for MRSA mediastinitis, and accumulate cases to investigate its efficacy. 相似文献
56.
Akio Sakamoto Tatsuya Yoshida Hidetaka Yamamoto Yoshinao Oda Masazumi Tsuneyoshi Yukihide Iwamoto 《Journal of orthopaedic science》2007,12(4):361-365
Background Congenital pseudarthrosis of the tibia (CPT) is frequently, but not always, associated with neurofibromatosis type 1 (NF1).
Double inactivation of the NF1 gene has been reported to be the pathogenesis of CPT in NF1 cases.
Methods We analyzed the loss of heterozygosity (LOH) of the NF1 gene in cases of CPT with NF1 to examine whether double inactivation was seen in the case. In addition to morphological analysis,
immunoexpression of differentiation markers was examined.
Results and discussion The tibia tapered with the zone phenomenon from mature to immature bone with osteoblastic rimming, resembling osteofibrous
dysplasia. Osteosclerotic bowed bone with a small number of osteoclasts suggested dysfunction of bone remodeling. Fibrous
tissue at the site of pseudarthrosis was associated with the periosteum and demonstrated myofibroblastic differentiation accompanied
by massive cartilage formation, suggesting some misdirection during the differentiation of periosteum to myofibroblasts or
chondrocytes. LOH of the NF1 gene locus was not seen in fibrous tissue. This result suggests that CPT is not accompanied by double inactivation in every
NF1 case. 相似文献
57.
Takao Hattori MD Toshihiro Hirai Minoru Niimoto Tetsuya Toge Yukihisa Miyoshi Tatsuya Yoshihara Sunao Otagaki Yoshinori Yamashita 《Surgery today》1986,16(2):90-97
Transabdominal resection for esophagocardial cancer and reestablishment of alimentary continuity using bypass methods were
performed in 76 patients. Thirteen underwent a bypass with a gastric tube and in 30, a colonic segment was prepared. In the
remaining 33, a jejunal segment was used as a bypass organ, with considerable success. The 5 year survival rates were 68.8
per cent in those with stages (I+II), 16.5 per cent in those with stage III, 12.6 per cent in those with stage IV and 22.5
per cent in all cases, indicating similar results compared to those with cancer located in the upper third of the stomach
with the limited proximal extension within the esophagocardial junction and operated on during the same period. 相似文献
58.
Sumiya Ishigami Shuichi Hokita Shoji Natsugoe Masahiro Tokushige Tetsushi Saihara Hirohumi Iwashige Kuniaki Aridome Takashi Aikou 《World journal of surgery》1998,22(10):1056-1060
n
= 25) and node-negative (
n
= 81) groups. Among several pathologic factors, the diameter of the tumor and lymphatic involvement were significantly correlated
with nodal involvement. Within the submucosal layer the depth of invasion and the horizontal cancerous expansion also correlated
with lymph node disease (
p
< 0.05). The size of the tumor did not correlate with the length of submucosal infiltration (
r
= 0.12,
p
= 0.1). Patients with both slight invasion into the submucosa and less than 5 mm of horizontal expansion were often negative
for lymph node involvement and thus may benefit from local surgery as an alternative to gastrectomy. 相似文献
59.
Norio Ohkoshi Hldehlro Mizusawa Nobuko Shiraiwa Shin'Ichi Shoji Katsutoshi Harada Kazuo Yoshizawa 《Muscle & nerve》1995,18(11):1265-1271
Lmmunohistochemical analyses were made of the superoxide dismutases (Mn-SOD and CuiZn-SOD) in biopsied muscles from 7 patients with mitochondrial encephalomyopathies that included mitochondrial encephalomyopathy, lactic acidosis and strokelike episodes (MELAS), and chronic progressive external ophthalmoplegia (CPEO). Mn-SOD mainly was present in the subsarcolemmal region, but it also was found in a coarsely granular, reticular, or diffuse pattern of staining within the muscle fibers. These Mn-SOD-positive fibers corresponded almost completely to the ragged-red fibers. The immunoreaction for CuiZn-SOD was weakly positive in some of the muscle fibers positive for Mn-SOD. In CPEO, Mn-SOD-positive fibers predominantly showed decreased cytochrome c oxidase (COX) activity. In MELAS, Mn-SOD-positive fibers tended to be stained deeply for COX although a few were COX-negative. These findings suggest that Mn-SOD-positive fibers can be used to make a differential diagnosis between CPEO and MELAS and that in mitochondrial encephalomyopathies Mn-SOD in the raggedred fibers may protect against oxidative stress. © John Wiley & Sons, Inc. 相似文献
60.
Nobuhiro Yuki Shuzo Sato Shoji Tsuji Kimiaki Ogawa Tadashi Miyatake 《Annals of neurology》1993,33(6):655-657
We performed human leukocyte antigens(HLA)typing for class I antigens on 19 Japanese patients with Fisher's syndrome. We demonstrated a statistically significant association between the disease and the HLA-B39 antigen. 相似文献