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1Pathological classification of intrahepatic cholangiocarcinoma based on a new concept显示文摘Intrahepatic cholangiocarcinoma (ICC) arises from the lining epithelium and peribiliary glands of the intrahepatic biliary tree and shows variable cholangiocytic dif-f-e-re-ntiation. To date-,ICC was large-ly classifie-d into adenocarcinoma and rare variants. Herein,we propose to subclassify the former,based on recent progress in the-study of-ICC including the-gross classification and hepatic progenitor/stem cells and on the pathological similarities between biliary and pancreatic neoplasms. That is,ICC is classifiable into the conventional (bile duct) type,the bile ductular type,the intraductal neoplasm type and rare variants. The conventional type is further divided into the small duct type (peripheral type) and large bile duct type (perihilar type). The former is a tubular or micropapillary adenocarcinoma while the latter involves the intrahepatic large bile duct. Bile ductular type resembles proliferated bile ductules and shows a replacing growth of the hepatic parenchyma.Hepatic progenitor cell or stem cell phenotypes such as neural cell adhesion molecule expression are frequently expressed in the bile ductular type. Intraductal type includes papillary and tubular neoplasms of the bile duct (IPNBs and ITNBs) and a superficial spreading type. IPNB and ITNB show a spectrum from a preneoplastic borderline lesion to carcinoma and may have pancreatic counterparts. At invasive sites,IPNB is associated with the conventional bile duct ICC and mucinous carcinoma. Biliary mucinous cystic neoplasm with ovarian-like stroma in its wall is different from IPNB,particularly IPNB showing cystic dilatation of the affected ducts. Rare variants of ICC include squamous/adenosquamous cell carcinoma,mucinous/signet ring cell carcinoma,clear cell type,undifferentiated type,neuroendocrine carcinoma and so on. This classification of-ICC may ope-n up a ne-w fie-ld of-re-se-arch of-ICC and contribute-to the-clini cal approach to ICC.Yasuni Nakanuma Yasunori Sato Kenichi Harada Mokoto Sasaski Hiroko Ikeda 2010World Journal of Hepatology2010,2,12:34
217β-雌二醇对雄性金鱼卵黄原蛋白的诱导作用显示文摘采用腹腔注射17β-雌二醇的方法诱导雄性金鱼卵黄原蛋白产生,注射浓度为0.05mg·g-1BW,诱导2周后取尾静脉血,离心分离血浆,进行血浆常规聚丙烯酰胺凝胶电泳,通过对卵黄原蛋白特性基团磷、脂和糖蛋白的染色,确定了卵黄原蛋白在电泳图谱上的位置,开发了一种简便、高效的定性卵黄原蛋白的聚丙烯酰胺凝胶电泳法。电泳结果表明,在0.05mg·g-1BW的注射浓度下,2周后17β-雌二醇诱导了雄性金鱼卵黄原蛋白产生,并通过ELISA检测卵黄原蛋白的平均含量为690.2ng·mL-1,与对照组雄性金鱼平均含量为10.7ng·mL-1的差异极显著(P<0.01),比雌性对照组检出量285.5ng·mL-1高1倍多;17β-雌二醇诱导组雄鱼血浆钙离子和血总蛋白含量明显增加。邴欣 汝少国 Isoda Hiroko 姜明 王蔚 王诗红 2004水产学报2004,28,3:24
3虚拟货币及其扩展:初步思考显示文摘随着信息加密和网络计算机技术日趋成熟,科技正在推动全球经济的转型变革。虚拟货币的产生在此过程中又显得至关重要。虚拟货币方案在许多情况下便于对等网络交互绕过传统的中央结算所。虚拟货币及其关联技术(特别是基于区块链的分布式账本)正在迅速发展,其未来前景难以预测。虚拟货币带来了许多潜在益处,包括更快速、高效的支付和转账等,并将最终促进普惠金融。一些虚拟货币方案背后的分布式账本技术提供的潜在益处将远超虚拟货币本身。但是,虚拟货币的出现也引发了许多潜在风险,如成为洗钱、恐怖融资、偷税漏税和欺诈等犯罪的工具。虚拟货币虽然目前的规模仍非常有限,对现阶段货币政策实施产生的风险亦甚微,但随着新技术的广泛应用,其对金融稳定产生的影响会日益显现。有关虚拟货币的有效监管对策还处于起步阶段。虚拟货币的在国家层面跨越了不同机构的职责,并在全球范围内操作,其监管难度很大。并且,许多虚拟货币在传统金融系统之外运作,缺乏透明度,其操作过程更难以被监管。各国监管机构已开始着手应对这些挑战且方式各异。需要注意的是,国家主管部门需认真权衡监管方式,既要适当处置风险又不能扼杀创新。为了在国家层面推进发展进程和促进政策的完善,国际层面也应进行更多努力。随着经验的不断积累,可考虑提出国际标准和最优方法,为不同领域的最优监管对策提供指导,从而促进跨辖区的协调。也可在此类标准基础上,为一些领域设立跨国合作和协调的框架。何东 卡尔·哈伯梅尔 罗斯·莱科 郭建伟 郇志坚 Vikram Haksar Yasmin Almeida Mikari Kashima Nadim Kyriakos-Saad Hiroko Oura Tahsin Saadi Sedik Natalia Stetsenko Concepcion Verdugo.Yepes 2016金融监管研究2016,,4:22
4Natural populations of lactic acid bacteria in douchi from Yunnan Province,China显示文摘This research was aimed at isolating and identifying the predominant lactic acid bacteria(LAB) in the traditional Chinese salt-fermented soybean food,douchi,from Yunnan,China.The predominant LAB present were isolated and identified by conventional culture-dependent methods combined with molecular biological methods.Two hundred and sixty isolates were obtained from thirty kinds of traditional fermented douchi from six cities and counties in Yunnan,and those strains were divided into twelve groups by their morphological and biochemical characteristics.Based on 16S ribosomal DNA(rDNA) sequencing and analysis,56 representative strains were identified as belonging to 6 genera and 14 species:Lactobacillus(4 spp.),Weissella(3 spp.),Pediococcus(2 spp.),Staphylococcus(2 spp.),Enterococcus(1 sp.),and Bacillus(2 spp.).The results show that douchi contains a large natural population of LAB of diverse composition from which some strains could be selected as starters for functional fermented foods.This is the first study on the original douchi from Yunnan,and the results suggest that it may be a useful source for the isolation of LAB.This study has also laid a foundation for further research on developing functional douchi products.Chen-jian LIU Fu-ming GONG Xiao-ran LI Hai-yan LI Zhong-hua ZHANG Yue FENG Hiroko NAGANO 2012Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)2012,13,4:16
5Comparative study: Vonoprazan and proton pump inhibitors in Helicobacter pylori eradication therapy显示文摘AIM To compare the effectiveness and safety of vonoprazan-based therapy with proton pump inhibitor(PPI)-based therapies to treat Helicobacter pylori(H. pylori).METHODS We retrospectively analysed data from first-line(vonoprazan or PPI with 200 mg clarithromycin and 750 mg amoxicillin twice daily for 7 d)(n = 1353) and second-line(vonoprazan or PPI with 250 mg metronidazole and 750 mg amoxicillin twice daily for 7 d)(n = 261) eradication treatments for H. pylori- positive patients with associated gastrointestinal diseases from April 2014 to December 2015 at Hattori Clinic, Japan. The primary endpoint was the eradication rate, which was assessed with a full analysis set. The secondary endpoints were adverse events and related factors.RESULTS After the first-line treatments, the eradication rates for vonoprazan, esomeprazol, rabeprazole, and lansoprazole were 87.9%(95%CI: 84.9%-90.5%), 71.6%(95%CI: 67.5%-75.5%), 62.9%(95%CI: 52.0%-72.9%), and 57.3%(95%CI: 50.4%-64.1%), respectively. The vonoprazan eradication rate was significantly higher than that of the PPIs(P < 0.01). Interestingly, smoking did not affect the H. pylori eradication rate in the vonoprazan group(P = 0.34), whereas it decreased the rates in the PPI groups(P = 0.013). The incidence of adverse events in the vonop-razan group was not different from the PPI group(P = 0.054), although the vonoprazan group exhibited a wider range of adverse events. Vonoprazan-based triple therapy was highly effective as a second-line treatment, with an eradication rate similar to that of PPI-based therapy.CONCLUSION Vonoprazan might be superior to PPIs in first-line H. pylori therapy, particularly for smokers. However, caution is required due to possible adverse events.Kouichi Sakurai Hiroko Suda Yumi Ido Takayuki Takeichi Ayako Okuda Kiwamu Hasuda Masahiro Hattori 2017World Journal of Gastroenterology2017,23,4:16
6The 2007 WHO Classification of Tumours of the Central Nervous System显示文摘David N. Louis Hiroko Ohgaki Otmar D. Wiestler Webster K. Cavenee Peter C. Burger Anne Jouvet Bernd W. Scheithauer Paul Kleihues 2007Acta Neuropathologica2007,,2:13
7Hepatic steatosis as a possible risk factor for the development of hepatocellular carcinoma after eradication of hepatitis C virus with antiviral therapy in patients with chronic hepatitis C显示文摘AIM: To elucidate risk factors contributing to the development of hepatocellular carcinoma (HCC) among patients with sustained viral response (SVR) after interferon (IFN) treatment and to examine whether HCV-RNA still remained in the liver of SVR patients who developed HCC. METHODS: Two-hundred and sixty-six patients, who achieved SVR, were enrolled in this study. We retrospectively reviewed clinical, viral and histological features of the patients, and examined whether the development of HCC depends on several clinical variables using Kaplan-Meier Method. RT-PCR was used to seek HCV-RNA in 3 out of 7 patients in whom liver tissue was available for molecular analysis. RESULTS: Among the enrolled 266 patients with SVR, HCC developed in 7 patients (7/266; 2.6%). We failed to detect HCV-RNA both in cancer and non-cancerous liver tissue in all three patients. The cumulative incidence for HCC was significantly different depending on hepatic fibrosis (F3-4) (P = 0.0028), hepatic steatosis (Grade 2-3) (P = 0.0002) and age (≥ 55) (P = 0.021) at the pre-interferon treatment. CONCLUSION: The current study demonstrated that age, hepatic fibrosis, and hepatic steatosis at pre- interferon treatment might be risk factors for developing HCC after SVR.Atsushi Tanaka Satoko Uegaki Hiroko Kurihara Kiyoshi Aida Masaki Mikami Ikuo Nagashima Junji Shiga Hajime Takikawa 2007World Journal of Gastroenterology2007,13,39:12
8Immunotherapy for colorectal cancer显示文摘The incidence of colorectal cancer(CRC)is on the rise,and the prognosis for patients with recurrent or metastatic disease is extremely poor.Although chemotherapy and radiation therapy can improve survival rates,it is imperative to integrate alternative strategies such as immunotherapy to improve outcomes for patients with advanced CRC.In this review,we will discuss the effect of immunotherapy for inducing cytotoxic T lymphocytes and the major immunotherapeutic approaches for CRC that are currently in clinical trials,including peptide vaccines,dendritic cell-based cancer vaccines,whole tumor cell vaccines,viral vector-based cancer vaccines,adoptive cell transfer therapy,antibody-based cancer immunotherapy,and cytokine therapy.The possibility of combination therapies will also be discussed along with the challenges presented by tumor escape mechanisms.Shigeo Koido Toshifumi Ohkusa Sadamu Homma Yoshihisa Namiki Kazuki Takakura Keisuke Saito Zensho Ito Hiroko Kobayashi Mikio Kajihara Kan Uchiyama Seiji Arihiro Hiroshi Arakawa Masato Okamoto Jianlin Gong Hisao Tajiri 2013World Journal of Gastroenterology2013,19,46:11
9Elevation of the glycated albumin to glycated hemoglobin ratio during the progression of hepatitis C virus related liver fibrosis显示文摘AIM: To analyze the relationship between the glycated albumin (GA) to glycated hemoglobin (HbA1c) ratio and the histological grading of liver fibrosis.METHODS: The study retrospectively included consecutive hepatitis C virus positive chronic liver disease patients (n = 142) who had undergone percutaneous liver biopsy between January 2008 and March 2010 at our institution. The ratios of GA/HbA1c were calculated in all patients to investigate the relationship with the degree of the liver fibrosis. The values of the aspartate aminotransferase-to-platelet ratio index (APRI), an excellent marker for the evaluation of liver fibrosis, were also calculated. In addition, we combined the ratio of GA/HbA1c and the APRI in order to improve our ability to detect the presence of significant liver fibrosis. RESULTS: Sixty-one (43%) patients had either no fibrosis or minimal fibrosis (METAVIR score: F0-F1), while 25 (17%) had intermediate fibrosis (F2). Fifty-six (39%) patients had severe fibrosis (F3-F4) and 27 of them had cirrhosis (F4). The mean values of the GA/HbA1c increased with the progression of the fibrosis (F0-1: 2.83 ± 0.24, F2: 2.85 ± 0.24, F3: 2.92 ± 0.35, F4: 3.14 ± 0.54). There was a significant dif- ference between the F0-F1 vs F4, F2 vs F4, and F3 vs F4 groups (P < 0.01, P < 0.01, P < 0.01 and P < 0.05, respectively). The GA/HbA1c ratio was significantly higher in the patients with cirrhosis (F4) than in those without cirrhosis (F0-F3) (3.14 ± 0.54 vs 2.85 ± 0.28, P < 0.0001). The GA/HbA1c ratio was also significantly higher in the patients with severe fibrosis (F3-F4) than in those without severe liver fibrosis (F0-F2) (3.03 ± 0.41 vs 2.84 ± 0.24, P < 0.001). Furthermore, the GA/ HbA1c ratio was also significantly higher in the patients with significant fibrosis (F2-F4) than in those without significant liver fibrosis (F0-F1) (2.98 ± 0.41 vs 2.83 ± 0.24, P < 0.001). The diagnostic performance of the increased GA/HbA1c ratio (> 3.0) was as follows: its sensitivity and specificity for the detection of liver cirrhosis (F4) were 59.3% and 70.4%, respectively and its sensitivity and specificity for the detection of severe liver fibrosis (F3-F4) were 50.0% and 74.4%,respectively. With regard to the detection of significant fibrosis (F2-F4), its sensitivity was 44.4% and its specificity was 77.0%. Although even the excellent marker APRI shows low sensitivity (25.9%) for distinguishing patients with or without significant fibrosis, the combination of the APRI and GA/HbA1c ratio increased the sensitivity up to 42.0%, with only a modest decrease in the specificity (from 90.2% to 83.6%). CONCLUSION: The GA/HbA1c ratio increased in line with the histological severity of liver fibrosis, thus suggesting that this ratio is useful as a supportive index of liver fibrosis.Nobuhiro Aizawa Hirayuki Enomoto Hiroyasu Imanishi Masaki Saito Yoshinori Iwata Hironori Tanaka Naoto Ikeda Yoshiyuki Sakai Tomoyuki Takashima Takashi Iwai Ei-ichiro Moriwaki Soji Shimomura Hiroko Iijima Hideji Nakamura Shuhei Nishiguchi 2012World Journal of Hepatology2012,4,1:10
10Bone status assessment in Japanese subjects using speed of sound along the tibiaNobuyuki Miyatake Hiroko Muta Chigusa Murota Mari Haga Masafumi Fujii 2002Chinese Medical Journal2002,,2:9
11Efficacy of multislice computed tomography for gastroenteric and hepatic surgeries显示文摘AIM: To determine the efficacy of multislice CT for gastroenteric and hepatic surgery.METHODS: Dual-phase helical computed tomography was performed in 50 of 51 patients who underwent gastroenteric and hepatic surgeries. Twenty-eight, eighteen and four patients suffering from colorectal cancer, gastric cancer,and liver cancer respectively underwent colorectal surgery (laparoscopic surgery: 6 cases), gastrectomy, and hepatectomy. Three-dimensional computed tomography imaging of the inferior mesenteric artery, celiac artery and hepatic artery was performed. And in the follow-up examination of postoperative patients, multiplanar reconstruction image was made in case of need.RESULTS: Scans in 50 patients were technically satisfactory and included in the analysis. Depiction of major visceral arteries, which were important for surgery and other treatments, could be done in all patients.Preoperative visualization of the left colic artery and sigmoidal arteries, the celiac artery and its branches, and hepatic artery was very useful to lymph node dissection,the planning of a reservoir and hepatectomy. And multiplanar reconstruction image was helpful to diagnosis for the postoperative follow-up of patients.CONCLUSION: Three-dimensional volume rendering or multiplanar reconstruction imaging performed by multislice computed tomography was very useful for gastroenteric and hepatic surgeries.Hiroshi Ohtani Hidemi Kawajiri Yuichi Arimoto Koichi Ohno Yasuhisa Fujimoto Hiroko Oba Kenji Adachi Masaya Hirano Shoichi Terakawa Mitsuo Tsubakimoto 2005World Journal of Gastroenterology2005,11,10:9
12Elucidation of the relationship of BNIP3 expression to gemcitabine chemosensitivity and prognosis显示文摘AIM: To evaluate the significance of BNIP3 in the pathogenesis of pancreatic cancer, we analyzed the relationship between the expression of BNIP3 and survival rate of the patients with pancreatic cancer, or chemosensitivities in pancreatic cancer cell lines, particularly for gemcitabine, the first-line anti-tumor drug for pancreatic cancer. METHODS: To compare the expression level of BNIP3 with the resistance to gemcitabine, eight pancreatic cancer cell lines were subjected to gemcitabine treatment and the quantitative real-time RT-PCR method was used to evaluate BNIP3 expression. Immunohistochemical analysis was also performed using 22 pancreatic cancer specimens to study relationship between BNIP3 expression and survival rate. RESULTS: Although no significantly positive association between BNIP3 mRNA level and gemcitabine chemosensitivity was observed, pancreatic cancer cell lines that were sensitive to gemcitabine treatment tended to show high levels of BNIP3 expression. The converse, an absence of BNIP3 expression, was not correlated with gemcitabine resistance. We further compared the BNIP3 expression profiles of resected primary pancreaticcancer specimens with the prognosis of the patients, and found a tendency of favorable prognosis and low BNIP3 expression. CONCLUSION: High levels of BNIP3 expression cannot be used as one of the predicting factors for gemcitabine chemosensitivity, and some yet to be known factors will have to fill the gap for the accurate prediction of pancreatic cancer chemosensitivity to gemcitabine. However, BNIP3 expression may have an impact on prediction of prognosis of patients with pancreatic cancer.Masaharu Ishida Makoto Sunamura Toru Furukawa Masanori Akada Hiroko Fujimura Emiko Shibuya Shinichi Egawa Michiaki Unno Akira Horii 2007World Journal of Gastroenterology2007,13,34:8
13Identification of advanced spin-driven thermoelectric materials via interpretable machine learning显示文摘Machine learning is becoming a valuable tool for scientific discovery.Particularly attractive is the application of machine learning methods to the field of materials development,which enables innovations by discovering new and better functional materials.To apply machine learning to actual materials development,close collaboration between scientists and machine learning tools is necessary.However,such collaboration has been so far impeded by the black box nature of many machine learning algorithms.It is often difficult for scientists to interpret the data-driven models from the viewpoint of material science and physics.Here,we demonstrate the development of spin-driven thermoelectric materials with anomalous Nernst effect by using an interpretable machine learning method called factorized asymptotic Bayesian inference hierarchical mixture of experts(FAB/HMEs).Based on prior knowledge of material science and physics,we were able to extract from the interpretable machine learning some surprising correlations and new knowledge about spin-driven thermoelectric materials.Guided by this,we carried out an actual material synthesis that led to the identification of a novel spin-driven thermoelectric material.This material shows the largest thermopower to date.Yuma Iwasaki Ryohto Sawada Valentin Stanev Masahiko Ishida Akihiro Kirihara Yasutomo Omori Hiroko Someya Ichiro Takeuchi Eiji Saitoh Shinichi Yorozu 2019npj Computational Materials2019,,1:7
14A new index for non-invasive assessment of liver fibrosis显示文摘AIM:To construct and evaluate a new non-invasive fibrosis index for assessment of the stage of liver f ibrosis. METHODS:A new f ibrosis index (Fibro-Stiffness index) was developed in 165 of 285 patients with chronic hepatitis C, and was validated in the other 120 patients where liver biopsy was performed. Its usefulness was compared with liver stiffness (LS) measured by FibroScan, the aminotransferase-to-platelet ratio index, the Forns index and the FibroIndex. RESULTS: The Fibro-Stiffness index consists of LS,platelet count and prothrombin time. The values of the Fibro-Stiffness index differed signif icantly between neighboring f ibrosis stages except F0-F1. The area under the receiver operating characteristics curves of the Fibro-Stiffness index for prediction of F≥2 (0.90), F≥ 3 (0.90) and F= 4(0.92) in the estimation group and those for F≥ 3 (0.93) and F =4 (0.97) in the validation group were the highest among the 5 methods examined. The accuracy of the Fibro-Stiffness index had highest values for F≥2, F≥3 and F=4 in both the estimation and validation groups. The diagnostic performance for F= 4 was improved by a combination of the Fibro-Stiffness index with serum hyaluronic acid level. CONCLUSION: The Fibro-Stiffness index was constructed and validated. It showed superior diagnostic performance to other indices for F ≥ 2,3 and 4.Naohiro Ichino Keisuke Osakabe Toru Nishikawa Hiroko Sugiyama Miho Kato Shiho Kitahara Senju Hashimoto Naoto Kawabe Masao Harata Yoshifumi Nitta Michihito Murao Takuji Nakano Yuko Arima Hiroaki Shimazaki Koji Suzuki Kentaro Yoshioka 2010World Journal of Gastroenterology2010,16,38:7
15Biliary drainage strategy of unresectable malignant hilar strictures by computed tomography volumetry显示文摘AIM:To identify criteria for predicting successful drainage of unresectable malignant hilar biliary strictures(UMHBS) because no ideal strategy currently exists.METHODS:We examined 78 patients with UMHBS who underwent biliary drainage.Drainage was considered effective when the serum bilirubin level decreased by ≥ 50% from the value before stent placement within 2 wk after drainage, without additional intervention.Complications that occurred within 7 d after stent placement were considered as early complications.Before drainage, the liver volume of each section(lateral and medial sections of the left liver and anterior and posterior sections of the right liver) was measured using computed tomography(CT) volumetry.Drained liver volume was calculated based on the volume of each liver section and the type of bile duct stricture(according to the Bismuth classification).Tumor volume, which was calculated by using CT volumetry, was excluded from the volume of each section.Receiver operating characteristic(ROC) analysis was performed to identify the optimal cutoff values for drained liver volume.In addition, factors associated with the effectiveness of drainage and early complications were evaluated.RESULTS:Multivariate analysis showed that drained liver volume [odds ratio(OR) = 2.92, 95%CI:1.648-5.197; P < 0.001] and impaired liver function(with decompensated liver cirrhosis)(OR = 0.06, 95%CI:0.009-0.426; P = 0.005) were independent factors contributing to the effectiveness of drainage.ROC analysis for effective drainage showed cutoff values of 33% of liver volume for patients with preserved liver function(with normal liver or compensated livercirrhosis)and 50%for patients with impaired liver function(with decompensated liver cirrhosis).The sensitivity and specificity of these cutoff values were82%and 80%for preserved liver function,and 100%and 67%for impaired liver function,respectively.Among patients who met these criteria,the rate of effective drainage among those with preserved liver function and impaired liver function was 90%and 80%,respectively.The rates of effective drainage in both groups were significantly higher than in those who did not fulfill these criteria(P<0.001 and P=0.02,respectively).Drainage-associated cholangitis occurred in 9 patients(12%).A smaller drained liver volume was associated with drainage-associated cholangitis(P<0.01).CONCLUSION:Liver volume drainage≥33%in patients with preserved liver function and≥50%in patients with impaired liver function correlates with effective biliary drainage in UMHBS.Ei Takahashi Mitsuharu Fukasawa Tadashi Sato Shinichi Takano Makoto Kadokura Hiroko Shindo Yudai Yokota Nobuyuki Enomoto 2015World Journal of Gastroenterology2015,21,16:6
16A rotary-shear low to high-velocity friction apparatus in Beijing to study rock friction at plate to seismic slip rates显示文摘This paper reviews 19 apparatuses having highvelocity capabilities,describes a rotary-shear low to highvelocity friction apparatus installed at Institute of Geology,China Earthquake Administration,and reports results from velocity-jump tests on Pingxi fault gouge to illustrate technical problems in conducting velocity-stepping tests at high velocities.The apparatus is capable of producing plate to seismic velocities(44 mm/a to 2.1 m/s for specimens of 40 mm in diameter),using a 22 kW servomotor with a gear/belt system having three velocity ranges.A speed range can be changed by 103 or 106by using five electromagnetic clutches without stopping the motor.Two cam clutches allow fivefold velocity steps,and the motor speed can be increased from zero to 1,500 rpm in 0.1–0.2 s by changing the controlling voltage.A unique feature of the apparatus is a large specimen chamber where different specimen assemblies can be installed easily.In addition to a standard specimen assembly for friction experiments,two pressure vessels were made for pore pressures to 70 MPa;one at room temperature and the other at temperatures to 500 °C.Velocity step tests are needed to see if the framework of rate-and-state friction is applicable or not at high velocities.We report results from velocity jump tests from 1.4 mm/s to 1.4 m/s on yellowish gouge from a Pingxi fault zone,located at the northeastern part of the Longmenshan fault system that caused the 2008 Wenchuan earthquake.An instantaneous increase in friction followed by dramatic slip weakening was observed for the yellowish gouge with smooth sliding surfaces of host rock,but no instantaneous response was recognized for the same gouge with roughened sliding surfaces.Instantaneous and transient frictional properties upon velocity steps cannot be separated easily at high velocities,and technical improvements for velocity step tests are suggested.Shengli Ma Toshihiko Shimamoto Lu Yao Tetsuhiro Togo Hiroko Kitajima 2014Earthquake Science2014,27,5:6
17采用Caco-2和PC12细胞检测有机磷农药的细胞毒性显示文摘建立了采用哺乳动物细胞系Caco-2和PC12细胞检测有机磷农药细胞毒性的新方法。1 0μmol L甲基对硫磷、敌敌畏、氧乐果、辛硫磷处理经过单层培养的Caco-2细胞,随着农药处理时间的延长,Caco-2细胞跨上皮细胞电阻抗值逐渐降低,处理60min时,辛硫磷和甲基对硫磷对Caco-2细胞具有明显的透过性,约是正常组的1 5倍,4种农药对Caco-2细胞透过性由大到小的顺序为:甲基对硫磷,辛硫磷,敌敌畏,氧乐果;0 01μmol L的甲基对硫磷和辛硫磷使PC12细胞乙酰胆碱酯酶活性迅速降低,随着处理浓度的增加酶活性降低不明显;而小于1 0μmol L的氧乐果和敌敌畏呈现渐进降低的趋势,当浓度大于1 0μmol L时酶活性降低比较显著。汝少国 ISODA Hiroko 邴欣 2003环境科学研究2003,16,2:6
18Risk factors for perforation during endoscopic retrograde cholangiopancreatography in post-reconstruction intestinal tract显示文摘BACKGROUND Endoscopic retrograde cholangiopancreatography(ERCP) in patients with surgically altered anatomy has been a major challenge to gastrointestinal endoscopists with low success rates for reaching the target site as well as high complication rates. The knowledge of ERCP-related risk factors is important for reducing unexpected complications.AIM To identify ERCP-related risk factors for perforation in patients with surgically altered anatomy.METHODS The medical records of 187 patients with surgically altered anatomy who underwent ERCP at our institution between April 2009 and December 2017 were retrospectively reviewed. An analysis of patient data, including age, sex, type of reconstruction, cause of surgery, aim of ERCP, success rate of reaching target site,success rate of procedure, adverse events, type of scope, time to reach the target site, and duration of procedure, was performed. In patients with Billroth-Ⅱ reconstruction, additional potential risk factors were the shape of the inserted scope and whether the anastomosis was antecolic or retrocolic.RESULTS All patients(n = 187) had surgical anatomy, such as Billroth-Ⅰ(n = 22), Billroth-Ⅱ(n = 33), Roux-en-Y(n = 54), Child, or Whipple reconstruction(n = 75). ERCP was performed for biliary drainage in 43 cases(23%), stone removal in 29 cases(16%),and stricture dilation of anastomosis in 59 cases(32%). The scope was unable to reach the target site in 17 cases(9%), and an aimed procedure could not be accomplished in 54 cases(29%). Adverse events were pancreatitis(3%),hyperamylasemia(10%), cholangitis(6%), cholestasis(4%), excessive sedation(1%), perforation(2%), and others(3%). Perforation occurred in three cases, all of which were in patients with Billroth-Ⅱ reconstruction; in these patients, further analysis revealed loop-shaped insertion of the scope to be a significant risk for perforation(P = 0.01).CONCLUSION Risk factors for perforation during ERCP in patients with surgically altered anatomy were Billroth-Ⅱ reconstruction and looping of the scope during BillrothⅡ procedure.Shinichi Takano Mitsuharu Fukasawa Hiroko Shindo Ei Takahashi Sumio Hirose Yoshimitsu Fukasawa Satoshi Kawakami Hiroshi Hayakawa Hiroshi Yokomichi Makoto Kadokura Tadashi Sato Nobuyuki Enomoto 2019World Journal of Clinical Cases2019,7,1:6
19A novel negative regulatory mechanism of Smurf2 in BMP/Smad signaling in bone显示文摘Transforming growth factor-β(TGF-β)and bone morphogenetic protein(BMP)play important roles in bone metabolism.Smad ubiquitination regulatory factors(Smurfs)regulate TGF-β/BMP signaling via ubiquitination,resulting in degradation of signaling molecules to prevent excessive activation of TGF-β/BMP signaling.Though Smurf2 has been shown to negatively regulate TGF-β/Smad signaling,its involvement in BMP/Smad signaling in bone metabolism has not been thoroughly investigated.In the present study,we sought to evaluate the role of Smurf2 in BMP/Smad signaling in bone metabolism.Absorbable collagen sponges containing 3μg of recombinant human BMP2(rhBMP2)were implanted in the dorsal muscle pouches of wild type(WT)and Smurf2−/−mice.The rhBMP2-induced ectopic bone in Smurf2−/−mice showed greater bone mass,higher mineral apposition and bone formation rates,and greater osteoblast numbers than the ectopic bone in WT mice.In WT mice,the ectopic bone consisted of a thin discontinuous outer cortical shell and scant inner trabecular bone.In contrast,in Smurf2−/−mice,the induced bone consisted of a thick,continuous outer cortical shell and abundant inner trabecular bone.Additionally,rhBMP2-stimulated bone marrow stromal cells(BMSCs)from Smurf2−/−mice showed increased osteogenic differentiation.Smurf2 induced the ubiquitination of Smad1/5.BMP/Smad signaling was enhanced in Smurf2−/−BMSCs stimulated with rhBMP2,and the inhibition of BMP/Smad signaling suppressed osteogenic differentiation of these BMSCs.These findings demonstrate that Smurf2 negatively regulates BMP/Smad signaling,thereby identifying a new regulatory mechanism in bone metabolism.Junichi Kushioka Takashi Kaito Rintaro Okada Hiroyuki Ishiguro Zeynep Bal Joe Kodama Ryota Chijimatsu Melanie Pye Masahiro Narimatsu Jeffrey LWrana Yasumichi Inoue Hiroko Ninomiya Shin Yamamoto Takashi Saitou Hideki Yoshikawa Takeshi Imamura 2020Bone Research2020,8,4:6
20Efficacy of a novel auto-fluorescence imaging system with computer-assisted color analysis for assessment of colorectal lesions显示文摘AIM:To evaluate the efficacy of computer-assisted color analysis of colorectal lesions using a novel auto-fluorescence imaging(AFI)system to distinguish neoplastic lesions from non-neoplastic lesions and to predict the depth of invasion.METHODS:From January 2013 to April 2013,consecutive patients with known polyps greater than 5 mm in size who were scheduled to undergo endoscopic treatment at The Jikei University Hospital were prospectively recruited for this study.All lesions were evaluated using a novel AFI system,and color-tone sampling was performed in a region of interest determined from narrow band imaging or from chromoendoscopy findings without magnification.The green/red(G/R)ratio for each lesion on the AFI images was calculated automatically using a computer-assisted color analysis system that permits real-time color analysis during endoscopic procedures.RESULTS:A total of 88 patients with 163 lesions were enrolled in this study.There were significant differences in the G/R ratios of hyperplastic polyps(non-neoplastic lesions),adenoma/intramucosal cancer/submucosal(SM)superficial cancer,and SM deep cancer(P<0.0001).The mean±SD G/R ratios were 0.984±0.118in hyperplastic polyps and 0.827±0.081 in neoplastic lesions.The G/R ratios of hyperplastic polyps were significantly higher than those of neoplastic lesions(P<0.001).When a G/R ratio cut-off value of>0.89 was applied to determine non-neoplastic lesions,the sensitivity,specificity,positive predictive value(PPV),negative predictive value(NPV),and accuracy were 83.9%,82.6%,53.1%,95.6%and 82.8%,respectively.For neoplastic lesions,the mean G/R ratio was 0.834±0.080 in adenoma/intramucosal cancer/SM superficial cancer and 0.746±0.045 in SM deep cancer.The G/R ratio of adenoma/intramucosal cancer/SM superficial cancer was significantly higher than that of SM deep cancer(P<0.01).When a G/R ratio cut-off value of<0.77 was applied to distinguish SM deep cancers,the sensitivity,specificity,PPV,NPV,and accuracy were80.0%,84.4%,29.6%,98.1%and 84.1%,respectively.CONCLUSION:The novel AFI system with color analysis was effective in distinguishing non-neoplastic lesions from neoplastic lesions and might allow determination of the depth of invasion.Hiroko Inomata Naoto Tamai Hiroyuki Aihara Kazuki Sumiyama Shoichi Saito Tomohiro Kato Hisao Tajiri 2013World Journal of Gastroenterology2013,19,41:5
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