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排序方式: 共有1271条查询结果,搜索用时 15 毫秒
1.
Kazunori Aizawa Takeshi Hanaoka Hiroki Kasai Kaoru Kogashi Setsuo Kumazaki Jun Koyama Hiroshi Tsutsui Yoshikazu Yazaki Noboru Watanabe Osamu Kinoshita Uichi Ikeda 《Hypertension research》2006,29(2):123-128
The phosphodiesterase-5 (PDE-5) inhibitor, sildenafil, has been reported to produce sustained pulmonary vasodilatation in patients with pulmonary hypertension (PH). Recently, vardenafil, a more potent and selective PDE-5 inhibitor than sildenafil, has been approved for the treatment of erectile dysfunction. However, the long-term effects of oral vardenafil in patients with PH are unknown. We studied five consecutive patients with PH; one with primary pulmonary hypertension, two with chronic pulmonary thromboembolism, one with Eisenmenger syndrome (ventricular septal defect) and one with secondary pulmonary hypertension after a ventricular septal defect closure operation. In an acute hemodynamic trial, vardenafil (5 mg) significantly decreased both the pulmonary vascular resistance (PVR) and systemic vascular resistance (SVR) with an increase in cardiac output. In a chronic hemodynamic trial, the maintenance dose of vardenafil (10 to 15 mg) for 3 months significantly decreased the PVR, but not the SVR, with a 20.7% reduction of the PVR/ SVR ratio. Plasma brain natriuretic peptide (BNP) levels were also significantly decreased after 3 months. This pilot study demonstrates that long-term oral vardenafil therapy may be a safe and effective treatment for patients with PH. 相似文献
2.
Shoji Kubo Hiroaki Kinoshita Kazuhiro Hirohashi Takatsugu Yamamoto 《Journal of Hepato-Biliary-Pancreatic Surgery》1995,2(1):85-89
A case of cystadenocarcinoma of the liver is reported. The patient was a 73-year-old woman in whom a tumor was detected in
the lateral segment of the liver during a health examination. Ultrasonograms and computed tomograms showed a multilocular
cystic mass. Magnetic resonance imaging (MRI) showed a multilocular lowintensity mass, including a high-intensity portion
and a portal branch compressed by the tumor. MRI with gadolinium showed an enhanced cyst wall. The cystic part of the tumor
became smaller and the solid part became larger over a 1-month period, indicating that the tumor was malignant. Subsegmentectomy
(S3) was performed and cystadenocarcinoma with cystadenoma was diagnosed by histopathological examination. Identification of
changes in the appearance of a tumor should be helpful for the differential diagnosis of cystadenoma and cystadenocarcinoma. 相似文献
3.
K Takayasu Y Muramatsu N Moriyama S Yamazaki T Takayama S Hirohashi Y Shimamura A Takahashi 《Journal of computer assisted tomography》1992,16(2):212-215
To differentiate focal nodular hyperplasia (FNH) from other hepatic tumors, especially hepatocellular carcinoma, we evaluated the hemodynamics of histologically proved FNH in three patients, two by arterial angio-CT and one by microangiography of the resected specimen. These studies demonstrated the centrifugal blood supply of FNH (early filling of central tumor vessels radiating to periphery, and lobulated tumor stains with central low density area in the late phase), which could not be demonstrated by dynamic CT or hepatic angiography. Arterial angio-CT is useful as a further study, when differential diagnosis of FNH is uncertain by other imaging techniques. 相似文献
4.
One of the most problematic aspects of surgery for hepatocellular carcinoma (HCC) is the frequent development of multiple tumors. Determination of the origin of multiple tumors, i.e., multifocal or metastatic, is important for predicting the clinical course of the disease after surgery. In order to clarify the origin of multiple tumors of HCC genetically, we examined patterns of loss of heterozygosity (LOH) on chromosome 16 for DNA isolated from 43 HCCs resected from 19 patients by analysis of restriction fragment length polymorphism. The cases were classified macro- and microscopically into 3 groups: multifocal origin; metastatic origin; and undetermined. Classification based on morphological features was shown to be well correlated with patterns of LOH in multiple tumors of HCC. Different patterns of LOH on chromosome 16 were detected in 8 of 11 patients with tumors of morphologically multifocal origin, whereas they were detected in none of 5 patients with tumors of morphologically metastatic origin. Among five patients with tumors of morphologically undetermined origin, a difference of LOH pattern among the tumors was detected in two, whereas in the other three, the pattern was identical between the tumors. A different pattern of LOH among HCCs arising in situ showed that they were composed of different clones, strongly suggesting their independent clonal origin and multifocal development. These results show that not only appropriate morphological observation but also examination of the LOH pattern on a particular chromosome is useful in diagnosis of multifocal HCC. 相似文献
5.
6.
Cadherin dysfunction in a human cancer cell line: possible involvement of loss of alpha-catenin expression in reduced cell-cell adhesiveness. 总被引:37,自引:0,他引:37
Y Shimoyama A Nagafuchi S Fujita M Gotoh M Takeichi S Tsukita S Hirohashi 《Cancer research》1992,52(20):5770-5774
A human lung cancer cell line, PC 9, was analyzed to elucidate the molecular mechanisms of dysfunction of cadherin-mediated cell-cell adhesion in cancer. Although PC 9 cells strongly expressed E-cadherin at the cell membrane, which was indistinguishable immunochemically from functional E-cadherin, they did not show tight cell-cell adhesion and had reduced E-cadherin-mediated aggregation activity. Immunoprecipitation with E-cadherin and Western blot analysis revealed that PC 9 cells did not express alpha-catenin, a cadherin-associated protein, suggesting that this was the cause of the cadherin dysfunction in the cell line. In addition, Northern and Southern blot analyses disclosed homozygous deletion of part of the alpha-catenin gene, which might have resulted in the loss of alpha-catenin expression in PC 9 cells. 相似文献
7.
Frequent loss of heterozygosity for loci on chromosome 8p in hepatocellular carcinoma, colorectal cancer, and lung cancer. 总被引:29,自引:0,他引:29
M Emi Y Fujiwara T Nakajima E Tsuchiya H Tsuda S Hirohashi Y Maeda K Tsuruta M Miyaki Y Nakamura 《Cancer research》1992,52(19):5368-5372
Frequent loss of heterozygosity at chromosomal loci in a specific tumor type may indicate the presence of a tumor suppressor gene. We have examined loss of heterozygosity on chromosome 8p in paired tumor and constitutional DNA from 346 patients representing seven different types of human cancer. Frequent allelic losses were observed in hepatocellular carcinoma (22 of 46 cases, 47.8%), in colorectal cancer (12 of 26, 46.2%), and in non-small cell lung cancer (14 of 35, 40.0%), in contrast to low frequencies detected in breast cancer (5 of 56, 8.9%) and renal cell carcinoma (2 of 27, 7.4%). Ovarian cancer and gastric cancer showed intermediate frequencies of 33.3% and 22.2%. Subsequent analysis of 120 hepatocellular carcinomas and 94 colorectal cancers with five polymorphic markers along the short arm of chromosome 8 defined commonly deleted regions within the same chromosomal interval, 8p23. 1-8p21.3, suggesting that one or more tumor suppressor genes for both cancers may be present in that region. 相似文献
8.
Beta-catenin mutations are frequent in calcifying odontogenic cysts, but rare in ameloblastomas 总被引:2,自引:0,他引:2 下载免费PDF全文
Sekine S Sato S Takata T Fukuda Y Ishida T Kishino M Shibata T Kanai Y Hirohashi S 《The American journal of pathology》2003,163(5):1707-1712
We have reported previously that alterations to beta-catenin occur frequently in adamantinomatous craniopharyngioma. Based on its histological resemblance to some odontogenic tumors, we suspected the presence of common genetic alterations among these tumors. To address this issue, 11 cases of calcifying odontogenic cyst (COC) and 20 cases of ameloblastoma were investigated for the presence of beta-catenin mutations and beta-catenin expression. Ten COCs were successfully analyzed by direct sequencing, and nine of them were found to harbor somatic beta-catenin mutations. Immunohistochemically, all of the COCs showed nuclear and cytoplasmic expression of beta-catenin with a heterogeneous pattern. No beta-catenin mutations were found in ameloblastomas, except for one case of the follicular type. All follicular ameloblastomas exhibited moderate nuclear and cytoplasmic accumulation of beta-catenin, in contrast to the predominantly membranous expression seen in the plexiform type. beta-Catenin mutation is considered to be a characteristic genetic feature of COC, and may play a critical role in its histogenesis. Although ameloblastoma closely resembles COC histologically, the two have genetically distinctive features. 相似文献
9.
Frequent co-localization of Cox-2 and laminin-5 gamma2 chain at the invasive front of early-stage lung adenocarcinomas 总被引:7,自引:0,他引:7
Niki T Kohno T Iba S Moriya Y Takahashi Y Saito M Maeshima A Yamada T Matsuno Y Fukayama M Yokota J Hirohashi S 《The American journal of pathology》2002,160(3):1129-1141
Laminin-5 is an extracellular matrix protein that plays a key role in cell migration and tumor invasion. Cox-2 is an induced isoform of cyclooxygenases that plays an important role in carcinogenesis, suppression of apoptosis, angiogenesis, and metastasis of colon cancer. We report frequent co-expression of cox-2 and laminin-5 at the invasive front of early-stage lung adenocarcinomas. We investigated the expression of cox-2 and laminin-5 immunohistochemically in 102 cases of small-sized lung adenocarcinoma (maximum dimension, 2 cm or less). Cox-2 and laminin-5 were expressed in 97 (95.1%) and 82 (80.4%) cases, respectively. Both were preferentially localized in cancer cells at the cancer-stroma interface, although cox-2 tended to show a diffuse staining pattern in some cases. A comparison of their staining patterns revealed a striking similarity in their distribution in 24 cases, and a partial overlap between their localization in another 20 cases. Moreover, an overall correlation was found between the expression levels of cox-2 and laminin-5 (P = 0.018). To gain insight into the mechanisms that regulate the expression of these proteins, we additionally studied their expression in 58 cases of stage I lung adenocarcinoma, in which p53 status was determined by immunohistochemistry, polymerase chain reaction-single strand conformation polymorphism analysis, and direct sequencing. The results showed that tumors with mutant p53 tended to express more cox-2 than those with wild-type p53 (P = 0.080). Also, tumors that overexpressed p53 had higher levels of cox-2 and laminin-5 than those without p53 overexpression (P = 0.032 and 0.047, respectively). Further immunohistochemical analysis showed that tumors that overexpressed both epidermal growth factor receptor (EGFR) and erbB-2 had higher levels of cox-2 and laminin-5 than those without concomitant overexpression of these proteins (P = 0.014 and P = 0.018, respectively). To see whether EGFR signaling is involved in cox-2 and laminin-5 expression, we further conducted in vitro analyses using six lung adenocarcinoma cell lines (A549, HLC-1, ABC-1, LC-2/ad, VMRC-LCD, and L27). Western blot analyses showed that cox-2 mRNA levels, and to a lesser extent laminin-5 gamma2 mRNA levels, correlated with the expression levels of erbB-2 and the phosphorylated form of MAPK/ERK-1/2 protein. The addition of transforming growth factor-alpha increased both cox-2 and laminin-5 gamma2 mRNA levels in A549, ABC-1, and L27 with different kinetics; the induction of cox-2 occurred earlier than that of laminin-5 gamma2. Finally, the migration of ABC-1 cells was inhibited by MAP kinase kinase inhibitor PD98059 and a selective cox-2 inhibitor NS-398. In contrast, the migration of A549 cells was inhibited by PD98059, but much less effectively by NS-398. These results suggest that co-stimulatory mechanisms may exist that increase the expression of cox-2 and laminin-5 at the invasive front of lung adenocarcinomas and that EGFR signaling could be one of the mechanisms. Further investigations are warranted concerning the role of cox-2 and laminin-5 in cancer cell invasion and the significance of p53 and EGFR signaling in the regulation of cox-2 and laminin-5 expression. 相似文献
10.
Glutathione and its metabolites were examined for reactivity to acetaldehyde. When acetaldehyde was incubated with glutathione alone, there was only a slight decrease of acetaldehyde, while an apparently equimolar reaction between acetaldehyde and free sulfhydryl was observed with the addition of -glutamyltranspeptidase. Cysteinylglycine, the first metabolite in the glutathione breakdown by -glutamyltranspeptidase, showed a rapid and equimolar reactivity to acetaldehyde and such was comparable to the reaction seen withl-cysteine ord-penicillamine. In light of the chemical structure, cysteinylglycine probably conjugates with acetaldehyde to form thiazolidinecarboxylic acid derivatives, 2-methyl-thiazolidine-4-carbonyl-glycine, and if so, the alteration of glutathione metabolism by acetaldehyde during ethanol intoxication warrants further attention. 相似文献