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131.
132.
Ai Maeda Masao Nakata Kouichiro Yasuda Takuro Yukawa Shinsuke Saisho Riki Okita Yuji Hirami Katsuhiko Shimizu 《General thoracic and cardiovascular surgery》2013,61(9):542-545
Unknown primary large cell neuroendocrine carcinoma (LCNEC) in the mediastinum is extremely rare. In this report, we present a case of a 53-year-old man with superior vena cava (SVC) syndrome who developed LCNEC in the middle mediastinum. His chief complaint was facial edema. Chest X-ray revealed an abnormal shadow in the right upper mediastinum. Computed tomography (CT) scan of the chest revealed a 67-mm mass in the middle mediastinum. Tumor invasion caused constriction of the SVC. The patient underwent induction chemoradiotherapy with vinorelbin and cisplatin and concurrent radiation therapy. After induction therapy, the tumor size decreased remarkably and was resected completely. The pathological diagnosis was LCNEC. 相似文献
133.
Ogata H Hayashi M Tsuda H Suzuki N Maeno M Sugawara A Ogiso B 《Dental materials journal》2012,31(1):92-97
The aim of this study was to investigate mineralizing ability of a premixed calcium phosphate cement (premixed-CPC) compared to mineral trioxide aggregate (MTA) and zinc oxide eugenol cement (SuperEBA) in ROS17/2.8 cells. The measurements of cell proliferation, alkaline phosphatase (ALPase) activity and mineralized nodule formation in the presence or absence (control) of the test materials were performed using a cell culture insert method with the test materials placed on a porous membrane of culture plate insert. Mineralized nodules were detected by staining with alizarin red, and the calcium content of the mineralized nodules was determined quantitatively using a calcium assay kit. Premixed-CPC and MTA indicated significantly higher cell proliferation, ALPase activity, mineralized nodule formation, and calcium content in nodules than those of SuperEBA (p<0.05). The present results suggest that premixed-CPC has the same mineralizing ability as MTA. 相似文献
134.
135.
Shingo Ito Yu Fujino Seiryo Ogata Mio Hirayama-Kurogi Sumio Ohtsuki 《Journal of pharmaceutical sciences》2018,107(12):3163-3170
The SLC22A18 gene, which encodes an orphan transporter, is located at the 11p15.5 imprinted region, an important tumor suppressor gene region. However, the role of SLC22A18 in tumor suppression remains unclear. Here, we investigated the involvement of SLC22A18 in cell growth, invasion, and drug resistance of MCF7 human breast cancer cell line. Western blot analysis indicated that SLC22A18 is predominantly expressed at intracellular organelle membranes. Quantitative proteomics showed that knockdown of SLC22A18 significantly altered the expression of 578 (31.0%) of 1867 proteins identified, including proteins related to malignancy and poor prognosis of breast cancer. SLC22A18 knockdown (1) increased MCF7 cell growth concomitantly with a >7-fold increase of annexin A8 (involved in cell growth and migration; a predictor of poor prognosis), (2) induced spherical morphology of MCF7 cells concomitantly with a nearly 3-fold increase of CD44 (involved in regulation of malignant phenotypes), and (3) increased chemosensitivity to vinca alkaloids concomitantly with a >80% reduction of doublecortin-like kinase 1 (involved in regulation of microtubule polymerization). Our results suggest that SLC22A18 may act as a tumor suppressor by regulating the expression levels of cell growth–related proteins, and vinca alkaloids might show therapeutic efficacy against low-SLC22A18–expressing breast cancer. 相似文献
136.
Kawashima I Ohsawa M Fukushige T Nagayama Y Niida Y Kotani M Tajima Y Kanekura T Kanzaki T Sakuraba H 《Clinica chimica acta; international journal of clinical chemistry》2007,378(1-2):142-146
BACKGROUND: In cultured fibroblasts from I-cell disease patients the transport of many lysosomal enzymes is defective, and affected cells contain inclusion bodies filled with undegraded substrates. However, the contents of these inclusion bodies have not been well characterized yet. We attempted to identify accumulated substances in cultured I-cell disease fibroblasts cytochemically. METHODS: Cultured fibroblasts from I-cell disease patients were double-stained with a monoclonal antibody to lysosome-associated membrane protein-1 (LAMP-1) and that to GM2 ganglioside, or a series of lectins that specifically bind to sugar moieties. RESULTS: The patients' cells were granularly stained with the antibody to GM2 ganglioside and the lectins including Maakia amurensis, Datura stramonium, and concanavalin A. Their localization was coincident with that of LAMP-1. CONCLUSIONS: GM2 ganglioside and various kinds of glycoconjugates having sialic acidalpha2-3galactose, galactosebeta1-4N-acetylglucosamine and mannose residues accumulate in enlarged lysosomes in I-cell disease fibroblasts. 相似文献
137.
Akiko Suzuki Kenichi Ogata Hiroki Yoshioka Junbo Shim Christopher AWassif Forbes DPorter Junichi Iwata 《骨研究(英文版)》2020,(1):39-52
Human linkage studies suggest that craniofacial deformities result from either genetic mutations related to cholesterol metabolism or high-cholesterol maternal diets. However, little is known about the precise roles of intracellular cholesterol metabolism in the development of craniofacial bones, the majority of which are formed through intramembranous ossification. Here, we show that an altered cholesterol metabolic status results in abnormal osteogenesis through dysregulation of primary cilium formation during bone formation. We found that cholesterol metabolic aberrations, induced through disruption of either Dhcr7(which encodes an enzyme involved in cholesterol synthesis) or Insig1 and Insig2(which provide a negative feedback mechanism for cholesterol biosynthesis), result in osteoblast differentiation abnormalities. Notably, the primary cilia responsible for sensing extracellular cues were altered in number and length through dysregulated ciliary vesicle fusion in Dhcr7 and Insig1/2 mutant osteoblasts. As a consequence, WNT/β-catenin and hedgehog signaling activities were altered through dysregulated primary cilium formation.Strikingly, the normalization of defective cholesterol metabolism by simvastatin, a drug used in the treatment of cholesterol metabolic aberrations, rescued the abnormalities in both ciliogenesis and osteogenesis in vitro and in vivo. Thus, our results indicate that proper intracellular cholesterol status is crucial for primary cilium formation during skull formation and homeostasis. 相似文献
138.
Wataru Hijikata Takuro Maruyama Tomotaka Murashige Daisuke Sakota Osamu Maruyama 《Artificial organs》2020,44(6):594-603
The use of contactless support technology for the impeller has led to an increase in the durability of ventricular assist devices (VADs), and these have been in clinical use worldwide. However, pump thrombosis and stroke are still issues to be solved. We have developed a method for detecting the thrombosis in a magnetically levitated blood pump without the need for additional sensors or other equipment. In the proposed method, a sinusoidal current is applied to the electromagnets used for the magnetic bearing, resulting in vibration of the impeller. The phase difference between the current and displacement of the impeller increases with pump thrombosis. First, we describe the principle by which the pump thrombosis is detected. Pump thrombosis reduces the narrowest fluid gap in the pump and this gives rise to a change in the phase difference. Second, we report on experiments in which we changed the narrowest fluid gap using oriented polypropylene tape and showed that decreasing the narrowest fluid gap resulted in an increase in phase difference. For these experiments, the measurements were repeated three times for each condition. Third, we examine the relationship between the pump thrombosis and the phase difference evaluated by observations of the underside of the impeller when operating the pump with porcine blood. Since light was unable to penetrate the blood layer, the erythrocytes were removed for this observation. Only one observation was made. The results showed the phase difference rapidly increased at the same moment when the pump thrombosis was observed. This implies the proposed method has the potential to detect the early stages of pump thrombosis. Finally, in vitro experiments to detect thrombosis when using whole porcine blood in the pump were conducted. The experiment was carried out five times. To intentionally form a thrombus inside the pump, the activated clotting time was controlled to be less than 200 s. In every case, the phase difference increased by more than one degree after tens of minutes. Then, the pump was disassembled and a small amount of pump thrombosis was observed. We conclude that real-time diagnosis of pump thrombosis may be realized by measuring the phase difference without the need for additional sensors. 相似文献
139.
Species identification of Asini Corii Collas (donkey glue) by PCR amplification of cytochrome b gene 总被引:1,自引:0,他引:1
Yukie Kumeta Takuro Maruyama Hiroshi Asama Yutaka Yamamoto Takashi Hakamatsuka Yukihiro Goda 《Journal of natural medicines》2014,68(1):181-185
Asini Corii Collas (ACC; donkey glue) is a crude drug used to promote hematopoiesis and arrest bleeding. Because adulteration of the drug with substances from other animals such as horses, cattle, and pigs has been found, we examined PCR methods based on the sequence of the cytochrome b gene for source species identification. Two strategies for extracting DNA from ACC were compared, and the ion-exchange resin procedure was revealed to be more suitable than the silica-based one. Using DNA extracted from ACC by the ion-exchange resin procedure, PCR methods for species-specific detection of donkey, horse, cattle, and pig substances were established. When these species-specific PCR methods were applied to ACC, amplicons were obtained only by the donkey-specific PCR. Cattle-specific PCR detected as little as 0.1 % admixture of cattle glue in the ACC. These results suggest that the species-specific PCR methods established in this study would be useful for simple and easy detection of adulteration of ACC. 相似文献
140.
Multifocal lesions with pancreatic atrophy in IgG4-related autoimmune pancreatitis: report of a case
Akifumi Kimura Junji Yamamoto Kazuo Hatsuse Suefumi Aosasa Kiyoshi Nishiyama Tadashi Maejima Sho Ogata Hideyuki Shimazaki Atsushi Kawaguchi Kazuo Hase 《Surgery today》2014,44(6):1171-1176
We herein report a case of IgG4-related autoimmune pancreatitis (AIP). A 72-year-old male with jaundice visited our hospital complaining of epigastralgia. A blood chemistry analysis revealed elevated serum levels of total bilirubin and DUPAN-II. Computed tomography (CT) revealed irregularly shaped pancreatic masses with a stricture of the main pancreatic duct (MPD) in the head and tail that were interposed by marked atrophy with MPD dilation in the body. F-18 fluorodeoxyglucose (FDG)-positron emission tomography/CT revealed abnormally intense FDG uptake only at the masses. During surgery, another small tumor was also found in the atrophied body; therefore, a total pancreatectomy was performed under the diagnosis of multiple pancreatic cancers. The histological analysis revealed fibrosis with dense and diffuse infiltrations of lymphocytes and IgG4-positive plasma cells. The pancreatic parenchyma of the body was firmly replaced by fibrosis. AIP can lead to the formation of multiple pancreatic lesions, and thus the correct diagnosis is occasionally difficult to establish in atypical cases. 相似文献