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51.
Somatic Mutations of the PTEN/MMAC1 Gene in Fifteen Japanese Endometrial Cancers: Evidence for Inactivation of Both Alleles 总被引:3,自引:1,他引:3
Keisuke Kurose Koichi Bando Koichi Fukino Yuichi Sugisaki Tsutomu Araki Mitsuru Emi 《Cancer science》1998,89(8):842-848
Loss of heterozygosity (LOH) of chromosome 10q is observed in approximately 40% of endometrial cancers. Mutations in PTEN/MMAC1 , a gene recently isolated from the 10q23 region, are responsible for two dominantly inherited neoplastic syndromes, Cowden disease and Bannayan-Zonana syndrome. Somatic mutations of this gene have also been detected in sporadic cancers of the brain, prostate and breast. To investigate the potential role of this putative tumor suppressor gene in endometrial carcinogenesis as well, we examined 46 primary endometrial cancers for LOH at the 10q23 region, and for mutations in the entire coding region and exon-intron boundaries of the PTEN/MMAC1 gene. LOH was identified in half of the 38 informative cases, and subtle somatic mutations were detected in 15 tumors (33%). Our results suggest that of the genes studied so far in endometrial carcinomas, PTEN/MMAC1 is the most commonly mutated one, and that inactivation of both copies by allelic loss and/or mutation, a pattern that defines genes as "tumor suppressors,'contributes to tumorigenesis in endometrial cancers. 相似文献
52.
Atsushi Yoshida Takashi Sugiyama Tsutomu Tabata Toshiharu Okugawa Norimasa Sagawa 《The Ultrasound Review of Obstetrics & Gynecology》2006,6(3):109-114
The usefulness of the vascular ultrasound in the field of obstetrics is now well recognized. Intima-media thickness (IMT) and elastic property of the common carotid artery are affected by pregnancy and vary with complications. Flow-mediated vasodilation (FMD) of the brachial artery reflects the vascular endothelial function and is reported to be useful in the management of complicated pregnancy, especially pre-eclampsia. For the screening of deep vein thrombosis of the lower extremities in the perinatal period, compression ultrasonography (CUS) is useful. 相似文献
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54.
Tsutomu Inatomi MD PhD Takahiro Nakamura MD PhD Shigeru Kinoshita MD PhD 《American journal of ophthalmology》2007,143(1):189-190
55.
Endogenous uveitis is a common cause of visual disability and blindness. The etiology of uveitis remains largely unknown but reasonable etiologic factors include infections. Superantigens are regarded as one of the leading causes of infectious etiology in autoimmune disease. However, the role of superantigens in uveitis remains unclear. In the present study, we investigated the effect of Staphylococcal enterotoxin B (SEB), a member of the superantigens, using an experimental model of autoimmune uveoretinitis (EAU). C57BL/6 mice were immunized with human interphotoreceptor retinoid binding protein (IRBP) peptide, and the severity of EAU disease was scored. Vehicle (PBS) alone or SEB dissolved in PBS was administered by intravenous injection on post-immunization day 10 or on post-immunization day 24. In addition, a systemic immune response study was performed to address the effects of SEB on systemic immunity. EAU was aggravated significantly by the injection of SEB at post-immunization day 10. Furthermore, relapse was induced by the injection of SEB at day 24. On the other hand, SEB injection without IRBP peptide immunization elicited no inflammatory changes in the uvea or retina. Furthermore, SEB enhanced not only the IRBP-specific T-cell proliferative responses but also IFN-γ and IL-17 production. Moreover, the intraocular expression levels of these cytokines was also enhanced by SEB injection. Both anti-CD4 and -Vβ8 Ab administration suppressed disease aggravation and the enhancement of IRBP-specific T-cell responses caused by SEB. These results suggest that SEB is involved significantly in the aggravation or recurrence of endogenous uveitis through activation of autoreactive uveitogenic T cells. 相似文献
56.
Murata T Miyase T Muregi FW Naoshima-Ishibashi Y Umehara K Warashina T Kanou S Mkoji GM Terada M Ishih A 《Journal of natural products》2008,71(2):167-174
From the stem bark of Ekebergia capensis, 10 new triterpenoid compounds, ekeberins A (1), B (2), C1 (3), C2 (4), C3 (5), D1 (6), D2 (7), D3 (8), D4 (9), and D5 (10), were isolated together with 17 known compounds. The structures of these new compounds were elucidated on the basis of the results of spectroscopic analysis, and the absolute configuration of compounds 6-10 were determined by partial synthesis from known compounds and using the Mosher ester method. Several of these compounds were screened in vitro against both chloroquine (CQ)-sensitive and -resistant Plasmodium falciparum isolates and were found to exhibit moderate antiplasmodial activity, with compounds 20 (7-deacetoxy-7-oxogedunin) and 27 (2-hydroxymethyl-2,3,22,23-tetrahydroxy-2,6,10,15,19,23-hexamethyl-6,10,14,18-tetracosatetraene) showing IC50 values of 6 and 7 microM, respectively. Compound 27 at a dose of 500 mg/kg showed moderate parasitemia suppression of 52.9% against P. berghei NK 65 in a mouse model. 相似文献
57.
Bioassay-guided fractionation of the root wood of Zanthoxylum wutaiense led to the isolation of 11 new compounds, wutaiensol methyl ether (1), demethoxywutaiensol methyl ether (2), methyl wutaiensate (3), methyl 7-hydroxyanodendroate (4), methyl 7-methoxyanodendroate (5), wutaifuranol (6), 7-methoxywutaifuranol (7), 7-methoxywutaifuranal (8), methyl wutaifuranate (9), methyl 7-methoxybenzofuran-5-carboxylate (10), and wutaipyranol (12), together with another 37 known compounds, of which one, 7-methoxybenzofuran-5-carboxaldehyde (11), was not previously known as a plant constituent. The structures of these isolates were identified by means of spectroscopic analysis. Five of these isolates were found to be antitubercular constituents, namely, methyl 7-methoxyanodendroate (5), 7-methoxywutaifuranal (8), wutaiensal (13), dictamnine (14), and gamma-fagarine (15), which exhibited antitubercular activity against Mycobacterium tuberculosis H37Rv, showing MIC values of 35, 35, 30, 30, and 30 microg/mL, respectively. 相似文献
58.
59.
Kamio M Oki T Inomoto Y Tsuji T Yoshinaga M Douchi T 《The journal of obstetrics and gynaecology research》2007,33(1):87-90
We encountered a 10-year-old prepubertal girl with a normal ovary and oviduct torsion. Hemorrhagic infarction of the ovary and oviduct occurred, and these structures were laparoscopically removed. Torsion of the normal ovary and oviduct in a prepubertal girl is discussed. 相似文献
60.
Sachiyo Onishi Masahiro Tajika Tsutomu Tanaka Keisaku Yamada Tomoyasu Kamiya Seiji Natsume Yasuhiro Shimizu Yasumasa Niwa 《Internal medicine (Tokyo, Japan)》2022,61(10):1531
Primary hepatocellular carcinoma (HCC) in patients <30 years old is extremely rare. In younger patients, HCC develops against a background of persistent hepatitis B virus infection. We herein report a 23-year-old woman with HCC with all-negative hepatitis virus markers developing in an apparently healthy liver. Imaging studies showed a 50-mm hypervascular mass in segment 4 of the left liver lobe, compatible with HCC. The patient underwent surgical resection. A histological examination showed the presence of poorly differentiated HCC. The patient was diagnosed with HCC developing in a healthy liver. This is an extremely rare case of non-B non-C HCC. 相似文献