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71.
Natsuko Kobayashi Hiroko Iijima Toshifumi Tada Yoko Shibata Takashi Nishimura Takashi Kumada Mariko Hashimoto Akiko Higashiura Masahiro Yoshida Junko Nishimura Nobuhiro Aizawa Naoto Ikeda Tomoyuki Takashima Ryo Takata Hiroki Nishikawa Yoshinori Iwata Hirayuki Enomoto Seiichi Hirota Etsuro Hatano 《Ultrasound in medicine & biology》2021,47(4):941-946
The aim of the study described here was to clarify the diagnostic value of the fluttering sign, a new sign that characterizes hepatic hemangiomas in gray-scale ultrasonography (US). It refers to a phenomenon in which the speckled echogenicity inside the hemangioma changes continuously and seems to be moving. A total of 172 hemangiomas diagnosed with contrast-enhanced US were evaluated. The fluttering sign was found in 123 of 172 hemangiomas (71.5%). Its prevalence was significantly higher than that of the marginal strong echo (89/172, 51.7%, p < 0.001), posterior acoustic enhancement (103/172, 59.9%, p = 0.031) and chameleon sign (100/172, 58.1%, p = 0.013). In addition, the fluttering sign was observed significantly more frequently in mixed or hypo-echoic tumors than in hyper-echoic tumors (p < 0.001), relatively large tumors (p < 0.001) and tumors that were less than 5 cm from the body surface (p = 0.015). The fluttering sign in gray-scale US has great potential to be a new complementary sign for the diagnosis of hemangioma. 相似文献
72.
Haruna Yagi Masato Nakaguro Masafumi Ito Yuki Okumura Seishiro Takahashi Yoichiro Aoshima Yasunori Enomoto Shiori Meguro Hideya Kawasaki Isao Kosugi Yoshie Shimoyama Hiroshi Ogawa Hisashi Tateyama Toshihide Iwashita 《Pathology international》2021,71(7):453-462
Micronodular thymoma with lymphoid stroma (MNT) is a rare thymic epithelial neoplasm subtype characterized by a micronodular tumor cell growth pattern and abundant lymphoid stroma. Micronodular thymic carcinoma with lymphoid stroma (MNCA) is considered as a malignant counterpart of MNT and exhibits a growth pattern similar to that of MNT but has histologic features reminiscent of thymic squamous cell carcinoma, such as cytologic atypia and CD5 and CD117 immunoexpression. Although both MNT and MNCA are characterized by abundant lymphoid stroma, it remains unknown whether there are differences in infiltrating lymphocytes between MNT and MNCA. We analyzed the immune microenvironment profile in eight MNT and three MNCA cases. The cell density of CD8-positive T cells was significantly higher in MNT than in MNCA, whereas that of FOXP3-positive T cells was significantly higher in MNCA than in MNT. There was no significant difference in the cell density of programmed death protein 1-positive T cells and programmed death ligand 1 expression between the MNT and MNCA cases. Our findings indicated that the immune microenvironment of MNCA differed from that of MNT and, compared with the T-cell profile of MNT, that of MNCA was more suppressive to patients′ antitumor immune response. 相似文献
73.
S. Shindo K. Fujii M. Shirakawa K. Uchida Y. Enomoto T. Iwama M. Kawasaki Y. Ando S. Yoshimura 《AJNR. American journal of neuroradiology》2015,36(11):2140
BACKGROUND AND PURPOSE:Rupture of the plaque fibrous cap and subsequent thrombosis are the major causes of stroke. This study evaluated morphologic features of plaque rupture in the carotid artery by using optical coherence tomography in vivo.MATERIALS AND METHODS:Thirty-six carotid plaques with high-grade stenosis were prospectively imaged by optical coherence tomography. “Plaque rupture” was defined as a plaque containing a cavity that had overlying residual fibrous caps. The fibrous cap thickness was measured at its thinnest part for both ruptured and nonruptured plaques. The distance between the minimum fibrous cap thickness site and the bifurcation point was also measured. Optical coherence tomography identified 24 ruptured and 12 nonruptured plaques.RESULTS:Multiple ruptures were observed in 9 (38%) patients: Six patients had 2 ruptures in the same plaque, 2 patients had 3 ruptures in the same plaque, and 1 patient had 5 ruptures in the same plaque. Most (84%) of the fibrous cap disruptions were identified at the plaque shoulder and near the bifurcation point (within a 4.2-mm distance). The median thinnest cap thickness was 80 μm (interquartile range, 70–100 μm), and 95% of ruptured plaques had fibrous caps of <130 μm. Receiver operating characteristic analysis revealed that a fibrous cap thickness of <130 μm was the critical threshold value for plaque rupture in the carotid artery.CONCLUSIONS:Plaque rupture was common in high-grade stenosis and was located at the shoulder of the carotid plaque close to the bifurcation. A cap thickness of <130 μm was the threshold for plaque rupture in the carotid artery.Rupture of the fibrous cap and subsequent thrombosis are the major causes of cardiovascular events such as heart attack and stroke.1–3 In a previous study of sudden coronary death, a fibrous cap thickness of 65 μm was chosen as a criterion of instability because for a cap to rupture, the average cap thickness was 23 ± 19 μm; 95% of caps measured <65 μm within a limit of only 2 SDs.1 Therefore, the fibrous cap thickness of <65 μm is now widely accepted as the definition of in vivo coronary vulnerable plaque that is prone to rupture. Disruption of the fibrous cap is frequently observed in symptomatic carotid plaques4,5 and is strongly associated with an ulceration appearance on angiography,6 which is considered an independent predictor of stroke on long-term follow-up in patients with symptomatic severe carotid stenosis.7 Redgrave et al8 examined the cross-sections of plaques with high-grade carotid stenosis and found that the optimum fibrous cap thickness for discriminating ruptured and nonruptured plaques was 200 μm; thus, it appears that there is no clear threshold for classifying plaques that are prone to rupture in vivo.Intravascular sonography, which is a widely used imaging method in the field of carotid artery intervention, has an axial resolution of 100–200 μm and a lateral resolution of 250 μm.9 Although it can visualize deep structures, intravascular sonography is not a suitable imaging technique for the detection of thin fibrous caps because its resolution is too low. Optical coherence tomography (OCT) has been introduced recently as a high-resolution imaging method.10,11 The typical OCT image has an axial resolution of 10 μm, approximately 10 times higher than that of any other clinically available diagnostic imaging technique, such as intravascular sonography. OCT provides an accurate representation of the thickness of the fibrous cap that could not be measured by other imaging modalities.12 In the present study, we evaluated the morphologic features of ruptured plaques in the carotid artery by using OCT. 相似文献
74.
75.
S Terauchi K Yamamoto H Fujii F Koyama S Sugimori H Enomoto M Yamanouchi H Nakano 《Hepato-gastroenterology》2001,48(39):675-677
We report a very rare early-stage case of mantle cell lymphoma, which arose from the rectum. A 60-year-old man presented with a small elastically hard polypoid lesion in the rectum. The lesion was 1.2 x 1.2 cm in size. As a preoperatively barium enema and endoscopy suggested a benign tumor of the rectum, he underwent local excision of a rectal polypoid mass transanally under spinal anesthesia. However, histological examination revealed a malignant lymphoma, because the lesion was histologically characterized by solid growths of small to medium-sized round cells. Furthermore, immunohistochemical tests revealed B-cell marker positivity and CD5 positivity, but cyclin D1 negativity. Since it was reported that lymphomas with a mantle cell lymphoma morphology and CD5 expression, but without cyclin D1 overexpression, exist in about 10% of mantle cell lymphoma cases, we diagnosed his disease as mantle cell lymphoma. To our knowledge, this is the first reported case of an early-stage mantle cell lymphoma, originating from the rectum. 相似文献
76.
Prognosis of unresectable hepatocellular carcinoma: an evaluation based on multivariate analysis of 90 cases. 总被引:12,自引:0,他引:12
Y Akashi C Koreeda S Enomoto S Uchiyama T Mizuno Y Shiozaki Y Sameshima K Inoue 《Hepatology (Baltimore, Md.)》1991,14(2):262-268
A multivariate analysis of data from 90 patients with unresectable hepatocellular carcinoma was performed using Cox's regression model to identify factors possibly affecting their prognoses. Thirty-one patients underwent arterial anticancer chemotherapy, and the remaining 59 patients received transcatheter arterial embolization with anticancer agents. Four of 27 variables tested for all the patients (i.e., encapsulation [p less than 0.05], gross appearance of hepatocellular carcinoma [p less than 0.01], clinical stage [p less than 0.01] and therapy [p less than 0.01]) were found to be prognostically significant. Five of 27 variables tested were prognostically significant for the transcatheter arterial embolization group; they were an extension rate of hepatocellular carcinoma (p less than 0.01), encapsulation (p less than 0.01), alpha-fetoprotein (p less than 0.01), prothrombin time (p less than 0.01) and serum sodium (p less than 0.01). Regression equations were used to describe a prognostic index. A prognostic index was defined as the regression equation derived from the results of a total of 90 patients; PI-1 = eY, where PI-1 = prognostic index 1 Y = 1.549 (gross appearance of hepatocellular carcinoma - 1.344) + 0.778 (encapsulation - 1.622) + 0.818 (clinical stage - 1.800) + 1.760 (therapy - 1.344) and prognostic index 2, the regression equation derived from the results of the transcatheter arterial embolization group of patients; PI-2 = eY, where PI-2 = prognostic index 2 Y = 1.210 (extension rate of hepatocellular carcinoma - 1.576) + 1.179 (encapsulation - 1.475) + 0.0001277 (alpha-fetoprotein - 1420.792) -0.039 (prothrombin time - 72.237) - 0.214 (serum sodium - 138.427).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
77.
Identification and characterization of a reptilian GnRH receptor from the leopard gecko 总被引:5,自引:0,他引:5
Gonadotropin-releasing hormone (GnRH) plays a pivotal role in the regulation of reproductive functions through interactions with its specific receptor. We describe the first molecular cloning and characterization of a full-length GnRH receptor (GnRHR) from the leopard gecko Eublepharis macularius. It has a distinct genomic structure consisting of five exons and four introns, compared with all the other reported GnRHR genes. A native GnRH form, cGnRH-II, stimulated inositol phosphate (IP) production in COS-7 cells transiently transfected with the GnRHR, in a dose dependent manner. The mRNA was expressed in all the tissues and organs examined. Molecular phylogenetic analysis revealed that the cloned GnRHR belongs to the type 2/nonmammalian I GnRHR. Low-expression levels were observed from the pituitary glands of reproductively active leopard geckos, indicating the possibility that there is at least one more type of GnRHR highly expressed in the pituitary gland for the gonadotropin secretion in this reptile. 相似文献
78.
A Suzuki T Takahashi K Nakamura R Tsuyuoka Y Okuno T Enomoto M Fukumoto H Imura 《Blood》1992,80(8):2052-2059
We investigated the cause of thrombocytosis in 14 patients with tumors producing colony-stimulating factor (CSF). Of the 14 patients, 10 had tumors producing granulocyte-CSF (G-CSF) and 4 had tumors producing granulocyte-macrophage--CSF (GM-CSF). Thrombocytosis of greater than 400 x 10(9)/L was noted in 8 of 10 patients with G-CSF-producing tumors and all 4 patients with GM-CSF-producing tumors. Median peak platelet counts were, respectively, 511 x 10(9)/L (range, 384 to 694 x 10(9)/L) and 579 x 10(9)/L (range, 526 to 910 x 10(9)/L) in patients with tumors producing G-CSF and GM-CSF. In most patients, thrombocytosis declined towards the terminal stage. High interleukin-1 (IL-1) and IL-6 levels were found in addition to CSFs in the plasma or culture supernatants of tumor cells obtained from most patients. In patients with GM-CSF-producing tumors, these specimens had megakaryocyte-CSF (Meg-CSF) activity, which was abolished by anti-GM-CSF antibody. These specimens also had megakaryocyte potentiating (Meg-Pot) activity attributable to both GM-CSF and IL-6. In patients with G-CSF-producing tumors, only Meg-Pot activity due to IL-6 was detected. These results indicate that the thrombocytosis in GM-CSF-producing tumors was caused by both the Meg-CSF activity of GM-CSF and the Meg-Pot activity of IL-6 plus GM-CSF, while that in G-CSF-producing tumors was due to the Meg-Pot activity of IL-6. 相似文献
79.
80.