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91.
Our previous studies demonstrated that specific inhibition of the BIG3‐PHB2 complex, which is a critical modulator in estrogen (E2) signaling, using ERAP, a dominant negative peptide inhibitor, leads to suppression of E2‐dependent estrogen receptor (ER) alpha activation through the reactivation of the tumor suppressive activity of PHB2. Here, we report that ERAP has significant suppressive effects against synergistic activation caused by the crosstalk between E2 and growth factors associated with intrinsic or acquired resistance to anti‐estrogen tamoxifen in breast cancer cells. Intrinsic PHB2 released from BIG3 by ERAP effectively disrupted each interaction of membrane‐associated ERα and insulin‐like growth factor 1 receptor beta (IGF‐1Rβ), EGFR, PI3K or human epidermal growth factor 2 (HER2) in the presence of E2 and the growth factors IGF or EGF, followed by inhibited the activation of IGF‐1Rβ, EGFR or HER2, and reduced Akt, MAPK and ERα phosphorylation levels, resulting in significant suppression of proliferation of ERα‐positive breast cancer cells in vitro and in vivo. More importantly, combined treatment with ERAP and tamoxifen led to a synergistic suppression of signaling that was activated by crosstalk between E2 and growth factors or HER2 amplification. Taken together, our findings suggest that the specific inhibition of BIG3‐PHB2 is a novel potential therapeutic approach for the treatment of tamoxifen‐resistant breast cancers activated by the crosstalk between E2 and growth factor signaling, especially in premenopausal women.  相似文献   
92.
Four new briarane-type diterpenoids, brianodins A-D ( 1- 4), were isolated from a soft coral, Pachyclavularia sp., and the structures and relative stereochemistry of 1- 4 were elucidated on the basis of spectroscopic data. The absolute configurations of 3 and 4 were assigned by the MTPA method. Brianodin A ( 1) showed a modest cytotoxicity.  相似文献   
93.
The malignant transformation of mature cystic teratoma is rare, thus occurring in only 1-2% of all cases. The most common malignancy arising in mature cystic teratoma is squamous cell carcinoma. Adenocarcinoma occurs with less frequency. We herein present a patient with an ovarian mature cystic teratoma who demonstrated a malignant transformation to well-differentiated adenocarcinoma. Malignant transformation was diagnosed preoperatively by contrast enhanced computed tomography (CT) and magnetic resonance imaging (MRI). Microscopically and immunohistochemically, the adenocarcinoma was considered to have arisen from the ciliated respiratory epithelium. After a 28-month of follow-up period, she remains free of the disease. This is the third reported case of adenocarcinoma arising in the respiratory epithelium of an ovarian mature cystic teratoma. Contrast enhanced CT and MRI are useful for making a preoperative diagnosis and an immunohistochemical study is helpful for defining its origin.  相似文献   
94.
Twin pregnancy consisting of a complete hydatidiform mole (CHM) along with a live co-existing fetus is a rare entity and difficult to diagnose. A 37-year-old Japanese woman demonstrated a living fetus, a placenta and a multicystic mass within one gestational sac on ultrasound at 10 weeks. Termination of the pregnancy was performed, and the specimen was classified as partial mole by macro- and microscopic findings. The karyotype of the molar tissue was 46XX. DNA polymorphism analysis demonstrated that fetal DNA showed bi-parental origin while molar DNA showed paternal origin only. Thus, this case was erroneously classified by ultrasonography, macroscopic and pathologic findings, then correctly diagnosed as a twin pregnancy with a CHM and co-existing normal twin fetus by DNA polymorphism analysis. Immunohistochemistry of p57(KIP2), the paternally imprinted and maternally expressed gene, supported the genetic diagnosis. This case suggested that conventional diagnostic methods were inadequate for accurate diagnosis of CHM with a co-existing fetus. DNA polymorphism analysis should be requested for the diagnosis of hydatidiform mole, especially in cases where it is difficult to discriminate between partial hydatidiform mole and CHM with a co-existing fetus.  相似文献   
95.
To evaluate the relationship between myocardial perfusion and fatty acid metabolism in canine myocardial infarction, 16 dogs were studied using thallium and 123I--methyl-iodophenyl pentadecanoic acid (BMIPP). Eight dogs (group A) had left anterior coronary arterial occlusion (6 h ligation), 6 dogs (group B) had reperfusion (3 h ligation and 1 h reperfusion) and 2 dogs served as the normal control. Myocardial imaging with BMIPP was excellent, owing to its higher uptake and longer retention in myocardium and rapid blood disappearance in addition to diminished liver and lung uptake. The mean half time value which was generated from the BMIPP myocardial washout curve, was significantly larger in the reperfused myocardium. The gamma camera imaging showed uncoupling of BMIPP and thallium (BMIPP uptake greater than thallium uptake) in five dogs in group B. On the other hand, all dogs in group A had a persistent defect in BMIPP and thallium uptake. Our findings indicate that the combination of BMIPP and thallium for myocardial imaging supply different information about the zone of infarction and ischemia, which may be useful for the assessment of myocardial viability.  相似文献   
96.
Currently, total arch replacement (TAR) using frozen elephant trunk (FET) technique is gaining popularity for various thoracic aortic pathologies. FROZENIX is the first commercialized open stent‐graft (OSG) in Japan, and it is a useful alternative to previously self‐made OSG. FROZENIX is easy to deploy compared with formerly launched OSGs. However, some challenges have been identified with FROZENIX. Herein, we present the cases of two patients in whom we encountered serious unexpected kinking of FROZENIX during TAR performed using FET, which was related to its structural property. The clinical course and the bailout are described.  相似文献   
97.
OBJECTIVE: To better determine the role of portal vein resection and its effect on survival, as well as to appreciate the impact of portal vein invasion on prognosis in hilar cholangiocarcinoma. SUMMARY BACKGROUND DATA: Hepatectomy with portal vein resection is sometimes performed for locally advanced hilar cholangiocarcinoma. However, the significance of microscopic invasion of the portal vein has not been determined. METHODS: Medical records of 160 patients with hilar cholangiocarcinoma who underwent macroscopically curative hepatectomy with (n = 52) or without portal vein resection (n = 108) were reviewed. Invasion of the portal vein was assessed histologically on the surgical specimen, and results were correlated with clinicopathologic features and survival. RESULTS: Surgical mortality, including all hospital deaths, was similar in patients who did and did not undergo portal vein resection (9.6% vs. 9.3%), but the primary tumor was more advanced in patients who underwent portal vein resection. Histologically, no invasion was found in 16 (30.8%) of resected portal veins. However, dense fibrosis adjacent to the portal vein was common, and the mean distance between the leading edge of cancer cells and the adventitia of the portal vein was 437 +/- 431 mum. The prognosis was worse in patients with than without portal vein resection (5-year survival, 9.9% vs. 36.8%; P < 0.0001). The presence or absence of microscopic invasion of the resected portal vein did not influence survival (16.6 months in patients with microscopic invasion vs. 19.4 months in those without; P = 0.1506). Multivariate analysis identified histologic differentiation, lymph node metastasis, and macroscopic portal vein invasion as independent prognostic factors. CONCLUSIONS: Microscopic invasion of the portal vein may be misdiagnosed clinically in patients with hilar cholangiocarcinoma. However, the distance between tumor and adventitia is so narrow that curative resection without portal vein resection is unlikely to be possible. Gross portal vein invasion has a negative impact on survival, and hepatectomy with portal vein resection can offer long-term survival in some patients with advanced hilar cholangiocarcinoma.  相似文献   
98.

Purpose  

The purpose of this retrospective study was to investigate the efficacy of transarterial chemoembolization (TACE) using cisplatin as a second-line treatment for advanced hepatocellular carcinoma (HCC) unresponsive to TACE using epirubicin–Lipiodol emulsion at our institution.  相似文献   
99.
100.
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