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Redox history of the Three Gorges region during the Ediacaran and Early Cambrian as indicated by the Fe isotope

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Geoscience Frontiers 2018年第1期9卷 155-172页

作者： Yusuke Sawaki Miyuki Tahata Tsuyoshi Komiya Takafumi hirata Jian Han Degan Shu Department of Earth and Planetary Sciences Tokyo Institute of Technology Department of Earth Science and Astronomy Graduate School of Arts and Sciences The University of Tokyo Geochemistry Research Center The University of Tokyo Department of Geology and Key Laboratory for Continental Dynamics Northwest University

The Ediacaran-Cambrian transition is characterized by numerous events such as the emergence of large multi-cellular metazoans and surface environmental *** on geological evidence,it has been proposed that this transition coincided with the increase in the atmospheric oxygen level that was key to the evolution of *** though ancient redox conditions can be inferred from the composition of sedimentary iron mineral species,this method is not necessarily applicable to all *** the Earth system,the cycling of iron is of considerable interest owing to its sensitivity to redox *** regarding the paleo-oceanic iron cycle is revealed in the iron isotopic composition of ironbearing ***,only limited iron isotopic data exists for Ediacaran-to Cambrianperiod *** circumvent this deficiency,we drilled a fossiliferous Ediacaran to Early Cambrian sedimentary succession in the Three Gorges region,South *** analyzed the iron isotope ratios(δ^(56/54)Fe)of pyrite grains in the drill cores using laser ablation multi collector inductively coupled plasma mass *** results demonstrate large variations inδ^(56/54)Fe,from-1.6 to 1.6‰,and positive iron isotope ratios are observed in many *** presence of positiveδ^(56/54)Fe in pyrite indicates that the ferrous iron in the seawater was partially oxidized,suggesting that seawater at Three Gorges was ferruginous during the Ediacaran and Early Cambrian ***,aggregated pyrite grains in organic carbon-rich black shales at Member 4 of the Doushantuo Formation and the base of the Shuijingtuo Formation yield near-zeroδ^(56/54)Fe values;this suggests that the ocean was transiently dominated by sulfidic conditions during these *** negativeδ^(56/54)Fe values,lower than-1‰,can be interpreted as a signature of *** DIR also might contribute in part to the re-mineralization of organic matter during the largest negative carbon isotope anoma

关键词： δ56/54Fe Pyrite Ediacaran Cambrian Three Gorges

Targeting hyaluronan for the treatment of pancreatic ductal adenocarcinoma

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Acta Pharmaceutica Sinica B 2016年第2期6卷 101-105页

作者： Norihiro Sato Xiao-Bo Cheng Shiro Kohi Atsuhiro Koga Keiji hirata Department of Surgery 1 School of Medicine University of Occupational and Environmental Health

Progression of cancer is often associated with interactions between cancer cells and extracellular matrix(ECM) surrounding them. Increasing evidence has suggested that accumulation of hyaluronan(HA), a major component of ECM, provides a favorable microenvironment for cancer progression. Pancreatic ductal adenocarcinoma(PDAC) is characterized typically by a dense desmoplastic stroma with a large amount of HA, making this molecule as an attractive target for therapy. Several studies have shown efficacy of inhibitors of HA synthesis or signaling for the treatment of PDAC. Recent studies have also demonstrated substantial improvements in the effects of chemotherapy by a targeted depletion of stromal HA in PDAC using an enzymatic agent. Thus, targeting HA has been recognized as a promising therapeutic strategy to treat this highly aggressive neoplasm. In this review article, we summarize our current understanding of the role of HA in the progression of PDAC and discuss possible therapeutic approaches targeting HA.

关键词： Pancreatic ductal adenocarcinoma Hyaluronan Tumor stroma Desmoplasia Tumor–stromal interaction Therapeutic target 4-Methylumbelliferone PEGPH20

A spectral response approach for detecting dominant phytoplankton size class from satellite remote sensing

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Acta Oceanologica Sinica 2010年第2期29卷 14-32页

作者： Robert J W Brewin Samantha J Lavender Nick J Hardman-Mountford Takafumi hirata School of Marine Science and Engineering University of Plymouth UK ARGANS Ltd Plymouth UK Plymouth Marine Laboratory (PML) Plymouth UK National Centre for Earth Observation PMLPlymouthUK Graduate School of Environmental Earth Science Hokkaido University NIOVV5kita-kuSapporo 060-0810 Japan National Centre for Earth Observation PMLPlymouthUK Graduate School of Environmental Earth ScienceHokkaido University NIOVV5kita-kuSapporo 060-0810Japan Graduate School of Environmental Earth Science Hokkaido University NIOVV5kita-kuSapporo 060-0810Japan

An important goal in ocean colour remote sensing is to accurately detect different phytoplankton groups with the potential uses including the validation of multi-phytoplankton carbon cycle models; synoptically monitoring the health of our oceans, and improving our understanding of the bio-geochemical interactions between phytoplankton and their environment. In this paper a new algorithm is developed for detecting three dominant phytoplankton size classes based on distinct differences in their optical signatures. The technique is validated against an independent coupled satellite reflectance and in situ pigment dataset and run on the 10-year NASA Sea viewing Wide Field of view Sensor （SeaWiFS） data series. Results indicate that on average 3.6% of the global oceanic surface layer is dominated by microplankton, 18.0% by nanoplankton and 78.4% by pieoplankton. Results, however, are seen to vary depending on season and ocean basin.

关键词： phytoplankton size remote sensing absorption ocean colour SeaWiFS

Mesenteric vein thrombosis following impregnation via in vitro fertilization-embryo transfer

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World Journal of Gastrointestinal Surgery 2017年第10期9卷 209-213页

作者： Masaaki hirata Hiroko Yano Tomoe Taji Yoshiharu Shirakata Department of Surgery Hyogo Prefectural Amagasaki General Medical Center Department of Obstetrics and Gynecology Hyogo Prefectural Amagasaki General Medical Center

Pregnancy is an acquired hypercoagulable state. Most patients with thrombosis that develops during pregnancy present with deep vein leg thrombosis and/or pulmonary embolism, whereas the development of mesenteric vein thrombosis(MVT) in pregnant patients is rare. We report a case of MVT in a 34-year-old woman who had achieved pregnancy via in vitro fertilization-embryo transfer(IVFET). At 7 wk of gestation, the patient was referred to us due to abdominal pain accompanied by vomiting and hematochezia, and she was diagnosed with superior MVT. Following resection of the gangrenous portion of the small intestine, anticoagulation therapy with unfractionated heparin and thrombolysis therapy via a catheter placed in the superior mesenteric artery were performed, and the patient underwent an artificial abortion. Oral estrogen had been administered for hormone replacement as part of the IVF-ET procedure, and additional precipitating factors related to thrombosis were not found. Pregnancy itself, in addition to the administered estrogen, may have caused MVT in this case. We believe that MVT should be included in the differential diagnosis of a pregnant patient who presents with an acute abdomen.

关键词： Mesenteric vein thrombosis Pregnancy In vitro fertilization-embryo transfer Oral estrogen

Pathophysiological analysis and strategy for stercoral perforation of the colon

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Open Journal of Gastroenterology 2012年第2期2卷 45-50页

作者： Koichi Sato Hiroshi Maekawa Mutsumi Sakurada Hajime Orita Tomoaki Ito yoshihiro Komatsu Fumiko hirata Ryo Wada Department of Pathology Juntendo Shizuoka Hospital Juntendo University School of Medicine Department of Surgery Juntendo Shizuoka Hospital Juntendo University School of Medicine

Perpose: In order to establish the pathophysiological features and strategy for stercoral perforation of the colon, we herein analyze a series of stercoral perforation of the colon. Method: Ten patients were diagnosed with stercoral perforation. Clinical features, primary diseases, triggers, causative bacteria in ascites, postoperative complications, pathological features, severity of the disease, and effect of direct hemoperfusion with polymyxin B immobilized fiber (PMX-DHP) were investigated. Results: Nine patients had a long history of serious and chronic constipation and 7 patients had hypertension. Causative bacteria in ascites during the operation were most commonly Escherichia coli. There were a lot of severe postoperative complications such as sepsis, disseminated intravascular coagulation, and acute lung injury. With regard to the microscopic findings of the perforation site, the intestinal wall showed severe nonspecific inflammatory changes, including an increase of mono-nuclear cells in the lamina propria. There were 4 hospital deaths, so the mortality rate was 40%. APACHE- II and SOFA score were high postoperation and 24 hours after the operation. PMX-DHP was performed in 8 cases of severe conditions of stercoral perforation of the colon. Because the catecholamine index improved within 24 hours, four of 8 cases were rescued. Conclusion: Most of the patients with stercoral perforation of the colon had severe postoperative complications. The severity of the disease was extremely high, therefore, early diagnosis based on pathophy-siological features and comprehensive therapies including PMX-DHP were necessary for strategy of treating stercoral perforation of the colon.

关键词： Stercoral Perforation of the Colon APACHE-II Score SOFA Score Polymyxin B Immobilized Fiber (PMX-DHP)

Endoscopic submucosal dissection as excisional biopsy for anorectal malignant melanoma:A case report

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World Journal of Clinical Cases 2019年第13期7卷 1652-1659页

作者： Shigeo Manabe Yoshio Boku Michiyo Takeda Fumitaka Usui Ikuhiro hirata Shuji Takahashi Department of Gastroenterology Kouseikai Takeda Hospital Kyoto 600-8558 Japan Fujita Clinic 67 Gokiya-cho Oomiya-dori Shichijo-kudaru Shimogyo-ku Kyoto 600-8267 Japan

BACKGROUND Anorectal malignant melanoma(AMM)is a rare disorder with an extremely poor *** there is currently no consensus on the treatment methods for AMM,surgical procedures have been the most common treatment methods used until *** recently encountered a case of AMM that we diagnosed using endoscopic submucosal dissection(ESD).To our knowledge,this is the first case of ESD for AMM,suggesting that ESD can potentially be a diagnostic and treatment method for *** S UMA/MARY A 77-year-old woman visited our hospital with a chief complaint of anal bleeding and a palpable rectal *** revealed a 20-mm protruded lesion in the lower *** obtaining biopsy specimens from the lesion,although a malignant rectal tumor was suspected,a definitive diagnosis was not *** ultrasonography revealed tumor invasion into the submucosal layer but not the muscular ***,we performed an excisional biopsy using *** examination of the ESD-resected specimen revealed tumor cells positive for Human Melanin Black-45,Melan-A,and ***,the tumor cells lacked melanin pigment;thus,a diagnosis of amelanotic AMM was *** the AMM had massively invaded the submucosal layer and both lymphatic and venous invasion were present,we closely monitored the patient without any additional therapy on the basis of her *** months after ESD,local recurrence was detected,and the patient consented to wide local *** USION It is suggested that ESD is a potential diagnostic and treatment method for AMM.

关键词： Endoscopic submucosal dissection Anorectal malignant melanoma Endoscopic mucosal resection Case report

Sunitinib-induced hyperammonemic encephalopathy in metastatic gastrointestinal stromal tumors:A case report

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World Journal of Clinical Cases 2023年第31期11卷 7629-7634页

作者： Takaoki Hayakawa Shinsuke Funakoshi Yasuo Hamamoto Kenro hirata Takanori Kanai Department of Internal Medicine Division of Gastroenterology and HepatologyKeio University School of MedicineShinjuku-ku 160-8582TokyoJapan Division of Medical Oncology Department of Internal MedicineTokyo Saiseikai Central HospitalMinato-ku 108-0073TokyoJapan Keio Cancer Center Keio University School of MedicineShinjuku-ku 160-8582TokyoJapan Department of Internal Medicine Keio University School of MedicineShinjuku-ku 160-8582TokyoJapan

BACKGROUND Sunitinib,a multi-targeted tyrosine kinase inhibitor(TKI),has been approved for the salvage treatment of gastrointestinal stromal tumors(GIST).Hyperammonemic encephalopathy is a rare but severe complication of sunitinib ***,we present the case of a 66-year-old male with metastatic GIST without underlying liver cirrhosis who developed sunitinib-induced hyperammonemic *** SUMMARY A 66-year-old male with metastatic GIST was admitted because of reduced *** was administered as the first-line systemic *** experienced repeated episodes of peritonitis due to tumor perforation,and surgery was *** disease was confirmed based on increased liver metastasis,and sunitinib was initiated as a salvage ***,23 d after the third course of sunitinib,he presented to the emergency room with an episode of altered consciousness and behavioral *** on the patient clinical history and examination findings,sunitinib-induced encephalopathy was *** was discontinued,and the patient was treated for *** patient had a normal level of consciousness four days later,and the serum ammonia level gradually *** further neurological symptoms were reported in subsequent *** TKI-induced hyperammonemic encephalopathy is potentially *** receiving TKIs experiencing adverse reactions should undergo systemic evaluation and prompt treatment.

关键词： Tyrosine protein kinase inhibitors Sunitinib malate Hyperammonemic encephalopathy Gastrointestinal stromal tumors Case report

Gastrointestinal stromal tumor of the ampulla of Vater:A case report

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World Journal of Gastroenterology 2014年第16期20卷 4817-4821页

作者： Masayoshi Kobayashi Nobuto hirata So Nakaji Toshiyasu Shiratori Hiroyuki Fujii Eiji Ishii Department of Gastroenterology Kameda Medical CenterChiba 296-0041Japan

Gastrointestinal stromal tumors (GISTs) usually develop in the stomach and small intestine and only rarely occur at the ampulla of Vater, with only 11 cases reported in the literature. We report a case of a GIST of the ampulla of Vater. A 36-year-old, previously healthy man presented with a loss of consciousness lasting a few minutes. A gastroduodenal endoscopy revealed a submucosal tumor with central ulceration at the ampulla of Vater. The enhanced computed tomography scan revealed a smooth-outlined hypervascular solid mass (24 mm × 30 mm) in the second part of the duodenum. Neither lymphadenopathy nor metastasis was observed. Magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography showed normal bile and pancreatic ducts. Biopsies were collected from the ulcerative lesion, and the tumor was diagnosed as a GIST. A submucosal tumor with central ulceration may be a characteristic form of GISTs of the ampulla of Vater, and biopsy studies are useful for the diagnosing such tumors. The patient underwent pancreatoduodenectomy, and the operative specimen revealed a 2.2-cm GIST with 1 mitosis per 50 high-power fields. The gold standard for treatment of GISTs is surgical resection without rupture of a capsule. If technically possible, local resection may be considered. However, when the location of the lesion presents challenges, a pancreatoduodenectomy should be performed for GIST of the ampulla of Vater.

关键词： Gastrointestinal stromal tumor Ampulla of Vater Submucosal tumor Bleeding Biopsy Pancreatoduodenectomy

Vascular endothelial growth factor 165b expression in stromal cells and colorectal cancer

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World Journal of Gastroenterology 2011年第44期17卷 4867-4874页

作者： Makoto Tayama Tomohisa Furuhata Yoshiko Inafuku Kenji Okita Toshihiko Nishidate Toru Mizuguchi Yasutoshi Kimura Koichi hirata the First Department of Surgery Sapporo Medical University

AIM:To characterize the implications of vascular endothelial growth factor(VEGF)-A in stromal cells and colorectal cancer and the expression of VEGF-A splice ***:VEGF-A expression in tumor and stromal cells from 165 consecutive patients with colorectal cancer was examined by *** association between VEGF-A expression status and clinicopathological factors was *** freshfrozen samples were obtained for laser capture microdissection to analyze the splice variants of ***:VEGF-A was expressed in 53.9% and 42.4% of tumor and stromal cells,***-A expression in tumor cells(t-VEGF-A) was associated with advanced clinical stage(stage 0,1/9;stage 1,2/16;stage 2,32/55;stage 3,38/66;stage 4,16/19,P < 0.0001).VEGF-A expression in stromal cells(s-VEGF-A) increased in the earlier clinical stage(stage 0,7/9;stage 1,6/16;stage 2,33/55;stage 3,22/66;stage 4,5/19;P = 0.004).Multivariate analyses for risk factors of recurrence showed that only s-VEGF-A expression was an independent risk factor for recurrence(relative risk 0.309,95% confidence interval 0.141-0.676,P = 0.0033).The five-year disease-free survival(DFS) rates of t-VEGF-A-positive and-negative cases were 51.4% and 62.9%,*** was no significant difference in t-VEGF-A expression *** five-year DFS rates of s-VEGF-A-positive and-negative cases were 73.8% and 39.9%,respectively.s-VEGFA-positive cases had significantly better survival than s-VEGF-A-negative cases(P = 0.0005).Splice variant analysis revealed that t-VEGF-A was mainly composed of VEGF165 and that s-VEGF-A included both VEGF165 and *** cases with no venous invasion(v0),the level of VEGF165b mRNA was significantly higher(v0 204.5 ± 122.7,v1 32.5 ± 36.7,v2 2.1 ± 1.7,P = 0.03).The microvessel density tended to be lower in cases with higher VEGF165b mRNA ***:s-VEGF-A appears be a good prognostic factor for colorectal cancer and includes VEGF165 and VEGF165b.

关键词： Colorectal cancer Vascular endothelial growth factor-A Vascular endothelial growth factor 165 Microvascular density Stromal cell