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21.
Nakamura K Funabashi N Miyauchi H Aminaka M Uehara M Ueda M Murayama T Hori Y Nakayama T Daimon M Kuroda N Kobayashi Y Komuro I 《International journal of cardiology》2008,127(3):437-441
We report the case of a 38-year-old Asian man with a pericardial hemangioma on the left main coronary artery. The patient presented initially at our hospital after cardiopulmonary resuscitation following an episode of ventricular fibrillation (VF). Because of spontaneous coved-type ST segment elevation on the higher intercostal space V1 to V2 in a 12-lead electrocardiogram, documented VF in the absence of structural heart disease, and a family history of sudden death, he was diagnosed with Brugada syndrome. Transesophageal echocardiography showed a smooth-surfaced mass with well-demarcated borders, directly above the left main coronary artery. Computed tomography confirmed the presence of the mass, which showed no enhancement at early phase, but did demonstrate homogenous enhancement at delay phase by contrast material. There were no findings from either the nuclear medicine or the tumor marker investigations which indicated that the mass located just above the main coronary arteries was malignant. Therefore, taken together, these findings suggested that the tumor might be a pericardial hemangioma. The relationship between the location of the hemangioma just above the left main coronary artery and the occurrence of VF was not clear, i.e. whether the presence of the hemangioma caused the stimulation of the left main coronary artery and as a result, led to the spasm of the left main coronary artery and the occurrence of VF. Furthermore, as the tumor did not extend into any of the adjacent structures, such as the coronary arteries or the right ventricular outflow tract, surgical resection was not performed; instead, the patient received a dual chamber implantable cardioverter-defibrillator. 相似文献
22.
Hepatic adrenal rest tumor: Diagnostic pitfall and proposed algorithms to prevent misdiagnosis as lipid‐rich hepatocellular carcinoma
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Tomoko Sugiyama Takuma Tajiri Shinichiro Hiraiwa Chie Inomoto Hiroshi Kajiwara Seiichiro Kojima Kouske Tobita Naoya Nakamura 《Pathology international》2015,65(2):95-99
We present a case of adrenal rest tumor of the liver in which differential diagnosis from lipid rich‐hepatocellular carcinoma (HCC) was challenging. The patient was a 50‐year‐old woman in whom a 3‐cm tumorous mass was discovered in segment 7 of the liver during computed tomography evaluation of a uterine leiomyoma. The preoperative diagnosis was HCC, and subsegmental liver resection was performed. The tumor appeared as a well‐demarcated golden yellow nodule consisting of clear or partially eosinophilic cells arranged in a trabecular pattern. The initial impression of this lesion was that of clear cell type or lipid‐rich type HCC because it stained positive for Hep Par1, but negative for arginase‐1 and positive for CD56 which is one of the neuroendocrine markers. The lesion also stained positive for SF‐1 and 3β‐HSD, both of which are markers of adrenocortical tissue. The final diagnosis was hepatic adrenal rest tumor. Hepatic adrenal rest tumor should be considered in the differential diagnosis of segment 7 tumor. A diagnostic algorithm that includes immunohistochemical staining for CD56 and arginase‐1 is to rule out the possibility of lipid‐rich HCC. 相似文献
23.
Jyunichiro Abe Yuta Kobayashi Koki Kawase Mizuki Tenjimbayashi Seimei Shiratori 《RSC advances》2018,8(12):6390
Lithium ion batteries (LIB) are the most extensively researched and developed batteries. Currently, LIBs are used in various applications such as electric vehicles (EV), hybrid EVs (HEV), plug-in HEVs, and energy storage systems. However, their energy density is insufficient and further improvement is required. In this study, we propose the facile synthesis of a self-standing, junction-less 3D carbon sponge electrode (3DCS) for improving the energy density. A self-standing structure can improve the energy density by reducing non-active materials such as binders and current collectors, in electrodes. We use a kitchenware melamine sponge as the carbon precursor. The utilization of materials mass-produced by existing facilities is crucial for ensuring availability and low costs. Such characteristics are imperative for industrialization. These self-standing 3DCS electrodes, fabricated using available low-cost melamine sponges, demonstrate high charge-rate characteristics with a capacity retention of 81.8% at 4000 mA g−1 and cycle durability with 95.4% capacity retention after 500 cycles, without current collector, binder, and conductive additives. This high availability, low-cost material with excellent characteristics is beneficial for research institutions and companies that do not have facilities.Conceptual diagram of junction-less 3D carbon sponge electrode. 相似文献
24.
Koki Tanaka Takuya Yamashita Goichi Yotsumoto Akira Ikoma Ryohei Ishibe Akira Taira 《Journal of hepato-biliary-pancreatic sciences》1994,1(3):289-293
We report here a long-term survivor of ruptured hepatocellular carcinoma (HCC). A 37-year-old Japanese man complained of sudden abdominal pain after taking an alcoholic drink. Ultrasonographic examination showed a large amount of fluid in the abdominal cavity. Emergency laparotomy was performed. A solid mass showing extrahepatic growth was present in the right lobe of the liver. No active bleeding site was detected, but the tumor was covered with old blood coagula. The tumor was covered with the greater omentum to prevent further hemorrhage. Following assessment of the extent of the tumor and of liver function, delayed hepatectomy was performed. Histological examination indicated the tumor to be HCC. Twenty-six months after initial hepatic resection, partial resection of the liver was performed again for recurrent tumor. The patient has survived without recurrence for more than 5 years. The long survival was due, we believe to the liver being non-cirrhotic, the delayed hepatic resection, and the early detection of the recurrent tumor. 相似文献
25.
Nozomi Asaoka Masakazu Ibi Hikari Hatakama Koki Nagaoka Kazumi Iwata Misaki Matsumoto Masato Katsuyama Shuji Kaneko Chihiro Yabe-Nishimura 《The Journal of neuroscience》2021,41(12):2780
Repetitive behavior is a widely observed neuropsychiatric symptom. Abnormal dopaminergic signaling in the striatum is one of the factors associated with behavioral repetition; however, the molecular mechanisms underlying the induction of repetitive behavior remain unclear. Here, we demonstrated that the NOX1 isoform of the superoxide-producing enzyme NADPH oxidase regulated repetitive behavior in mice by facilitating excitatory synaptic inputs in the central striatum (CS). In male C57Bl/6J mice, repeated stimulation of D2 receptors induced abnormal behavioral repetition and perseverative behavior. Nox1 deficiency or acute pharmacological inhibition of NOX1 significantly shortened repeated D2 receptor stimulation-induced repetitive behavior without affecting motor responses to a single D2 receptor stimulation. Among brain regions, Nox1 showed enriched expression in the striatum, and repeated dopamine D2 receptor stimulation further increased Nox1 expression levels in the CS, but not in the dorsal striatum. Electrophysiological analyses revealed that repeated D2 receptor stimulation facilitated excitatory inputs in the CS indirect pathway medium spiny neurons (iMSNs), and this effect was suppressed by the genetic deletion or pharmacological inhibition of NOX1. Nox1 deficiency potentiated protein tyrosine phosphatase activity and attenuated the accumulation of activated Src kinase, which is required for the synaptic potentiation in CS iMSNs. Inhibition of NOX1 or β-arrestin in the CS was sufficient to ameliorate repetitive behavior. Striatal-specific Nox1 knockdown also ameliorated repetitive and perseverative behavior. Collectively, these results indicate that NOX1 acts as an enhancer of synaptic facilitation in CS iMSNs and plays a key role in the molecular link between abnormal dopamine signaling and behavioral repetition and perseveration.SIGNIFICANCE STATEMENT Behavioral repetition is a form of compulsivity, which is one of the core symptoms of psychiatric disorders, such as obsessive-compulsive disorder. Perseveration is also a hallmark of such disorders. Both clinical and animal studies suggest important roles of abnormal dopaminergic signaling and striatal hyperactivity in compulsivity; however, the precise molecular link between them remains unclear. Here, we demonstrated the contribution of NOX1 to behavioral repetition induced by repeated stimulation of D2 receptors. Repeated stimulation of D2 receptors upregulated Nox1 mRNA in a striatal subregion-specific manner. The upregulated NOX1 promoted striatal synaptic facilitation in iMSNs by enhancing phosphorylation signaling. These results provide a novel mechanism for D2 receptor-mediated excitatory synaptic facilitation and indicate the therapeutic potential of NOX1 inhibition in compulsivity. 相似文献
26.
27.
Seven in absentia homolog 1A mediates ubiquitination and degradation of group 1 metabotropic glutamate receptors
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Moriyoshi K Iijima K Fujii H Ito H Cho Y Nakanishi S 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(23):8614-8619
Seven in absentia homolog 1A (Siah1A) is a member of the RING-finger-containing E3 ubiquitin ligases and has been shown to bind to the Siah-interacting domain (SID) at the carboxyl-terminal tails of the long splice forms of group 1 metabotropic glutamate receptors (mGluR1a and mGluR5). We examined the function of Siah1A in ubiquitination and degradation of group 1 mGluRs in heterologously expressing cell lines. Coexpression of Siah1A markedly decreased the SID-containing splice forms of group 1 mGluRs but not the SID-lacking mGluR1b splice form or the SID-deleted mGluR1a mutant. The decrease of mGluR1a resulted from accelerated protein turnover, as revealed by pulse-chase experiments. The Siah1A-mediated degradation of group 1 mGluRs was abrogated by not only mutations at the RING-finger domain of Siah1A but also treatment with a proteasome inhibitor. Siah1A coexpression induced strong ubiquitination of group 1 mGluRs. Replacements of lysine residues with arginine showed that Siah1A-mediated ubiquitination occurs at multiple lysine residues spanning both the seven-transmembrane region and carboxyl-terminal tail of mGluR5. In situ hybridization histochemistry showed a wide-spread distribution of Siah1 mRNAs, with high expression in the hippocampal pyramidal neurons and cerebellar Purkinje cells. Group 1 mGluRs play critical roles in the neural plasticity in both the hippocampal neurons and Purkinje cells. This investigation indicates that Siah1A serves as a selective ubiquitin ligase that mediates ubiquitination-dependent degradation of long splice variants of group 1 mGluRs and would contribute to posttranslational down-regulation of group 1 mGluRs. 相似文献
28.
29.
Mizushima T Sawa K Ochi K Tanioka H Wakuta A Matsushita K Shirahige A Kiura K Tanimoto M Koide N Harada H 《Journal of gastroenterology and hepatology》2005,20(6):910-914
BACKGROUND: Disorders of the motor function of the upper gastrointestinal tract have been implicated in the pathogenesis of non-ulcer dyspepsia. Approximately 50% of patients with abdominal symptoms (without ulcer) have normal gastric emptying. Apart from gastric emptying, other mechanisms are very important in the etiology of non-ulcer dyspepsia. METHODS: Gastric emptying and gallbladder motility were simultaneously investigated in 16 patients with non-ulcer dyspepsia and in 15 healthy controls. Fasting blood samples were taken, and pepsinogen levels were assayed. RESULTS: Gastric emptying time, fasting antral diameter, and post-prandial antral diameter were not significantly different between the patients with non-ulcer dyspepsia and the controls. Fasting gallbladder volume, the time required to reach minimal gallbladder residual volume, minimal gallbladder residual volume, and the serum levels of pepsinogen were not significantly different. Simple linear regression was used to summarize the relationship between gastric emptying time and time required to reach minimal gallbladder residual volume. In the controls, the gastric emptying time and time required to reach minimal gallbladder residual volume were linearly related. However, in the patients with non-ulcer dyspepsia, they were not related. CONCLUSIONS: These observations suggest that disturbance of coordination between gastric emptying and gallbladder emptying is a cause of the symptoms of non-ulcer dyspepsia. 相似文献