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Dive into the research topics where Norihisa Yada is active.

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Featured researches published by Norihisa Yada.


Intervirology | 2010

Non-Invasive Evaluation of Hepatic Fibrosis for Type C Chronic Hepatitis

Chie Tatsumi; Masatoshi Kudo; Kazuomi Ueshima; Satoshi Kitai; Emi Ishikawa; Norihisa Yada; Satoru Hagiwara; Tatsuo Inoue; Yasunori Minami; Hobyung Chung; Kiyoshi Maekawa; Kenji Fujimoto; Michio Kato; Akiko Tonomura; Tsuyoshi Mitake; Tsuyoshi Shiina

Objective: The aim of this study was to investigate liver fibrosis using non-invasive Real-time Tissue Elastography® (RTE) and transient elastography (FibroScan®) methods. Methods: RTE, FibroScan and percutaneous liver biopsy were all performed on patients with chronic liver disease, particularly hepatitis C, to investigate liver fibrosis. Results: FibroScan and RTE were compared for fibrous liver staging (F stage), which was pathologically classified using liver biopsy. In FibroScan, significant differences were observed between F1/F3 and F2/F4, but no such differences were observed between F1/F2, F2/F3 and F3/F4. In RTE, significant differences were observed between F1/F2, F2/F3 and F2/F4. But for F3/F4, no significant differences were observed. Conclusion: FibroScan and RTE correlated well with F staging of the liver. In particular RTE was more successful than FibroScan in diagnosing the degree of liver fibrosis.


Oncology | 2010

Hepatic Arterial Infusion Chemotherapy Using Low-Dose 5-Fluorouracil and Cisplatin for Advanced Hepatocellular Carcinoma

Kazuomi Ueshima; Masatoshi Kudo; Masahiro Takita; Tomoyuki Nagai; Chie Tatsumi; Taisuke Ueda; Satoshi Kitai; Emi Ishikawa; Norihisa Yada; Tatsuo Inoue; Satoru Hagiwara; Yasunori Minami; Hobyung Chung

Background: Although hepatic arterial infusion chemotherapy (HAIC) using low-dose 5-fluorouracil (5-FU) and cisplatin (low-dose FP) is commonly used for advanced hepatocellular carcinoma (HCC) with vascular invasion in Japan, few reports have investigated the efficacy and safety of this approach. We investigated the efficacy and toxicity of HAIC using low-dose FP for patients with advanced HCC as a phase II trial. Methods: Low-dose FP consisted of a continuous arterial infusion of 5-FU (250–500 mg/day, 5 days/week, for the first 2 weeks) and cisplatin (10 mg/day, 5 days/week, for the first 2 weeks). Then, 5-FU (1,000 mg/body for 5 h) and cisplatin (10 mg/body) were administered once weekly. Results: In these patients treated with low-dose FP, the response rate was 38.5%, the median time to progression was 4.1 months (95% CI 2.1–6.1 months) and the median survival time was 15.9 months (95% CI 9.8–22.0 months). The most frequent adverse events were myelosuppression such as neutropenia or thrombocytopenia. Conclusions: HAIC using low-dose FP is an effective treatment option for locally advanced HCC. However, it is not well tolerated hematologically because of potent pancytopenia and poor hepatic reserve. Therefore, this regimen should be performed carefully with regular monitoring of hematological function.


Liver cancer | 2015

Effectiveness of Sorafenib in Patients with Transcatheter Arterial Chemoembolization (TACE) Refractory and Intermediate-Stage Hepatocellular Carcinoma

Tadaaki Arizumi; Kazuomi Ueshima; Tomohiro Minami; Masashi Kono; Hirokazu Chishina; Masahiro Takita; Satoshi Kitai; Tatsuo Inoue; Norihisa Yada; Satoru Hagiwara; Yasunori Minami; Toshiharu Sakurai; Naoshi Nishida; Masatoshi Kudo

Background and Aims: Patients with intermediate-stage hepatocellular carcinoma (HCC) refractory to transcatheter arterial chemoembolization (TACE) are considered to be candidates for sorafenib. The aim of this study was to evaluate the superiority of conversion of treatment to sorafenib on overall survival (OS) for cases refractory to TACE. Methods: This was a retrospective cohort study carried out on 497 patients with HCC who were treated with TACE therapy at our hospital between January 2008 and December 2013. Fifty-six patients were diagnosed as refractory to TACE during their clinical course and they were divided into two cohorts, (1) those who switched from TACE to sorafenib and (2) those who continued TACE. The overall survival (OS) after the time of being refractory to TACE was evaluated between the two groups. Results: After refractoriness to TACE therapy was confirmed, 24 patients continued with TACE (TACE-group) and 32 patients underwent treatment conversion to sorafenib (sorafenib-group). The median OS was 24.7 months in the sorafenib-group and 13.6 months in the TACE-group (p=0.002). Conclusions: Conversion to sorafenib significantly improves the OS in patients refractory to TACE therapy with intermediate-stage HCC. Administration of sorafenib is therefore recommended in such circumstances of TACE treatment failure.


Oncology | 2013

Assessment of Liver Fibrosis with Real-Time Tissue Elastography in Chronic Viral Hepatitis

Norihisa Yada; Masatoshi Kudo; Hiroyasu Morikawa; Kenji Fujimoto; Michio Kato; Norifumi Kawada

Objective: The aim of this study was to assess prospectively the accuracy of measurement of liver fibrosis with real-time tissue elastography (RTE) in patients with chronic viral hepatitis. Methods: Two hundred and forty-five patients were prospectively enrolled. Nine image features were measured from strain images, and Liver Fibrosis Index (LFI) was calculated from these features. Fibrosis stage was diagnosed from pathological specimens obtained by ultrasound-guided biopsy. LFI and serological markers were compared with pathological diagnosis, and the diagnostic performance of RTE was compared. Results: LFI in stages F0-F1, F2, F3 and F4 was 1.58, 2.03, 2.40 and 2.86, respectively, demonstrating a stepwise increase with increasing severity of liver fibrosis (p < 0.001). LFI in F2 did not significantly differ from that in F3, whereas for all other combinations of stages, there were significant differences. The area under the receiver operating characteristic curve of the LFI, platelet count, aspartate/alanine aminotransferase ratio, aspartate aminotransferase-to-platelet ratio, and FibroIndex for predicting F3 stage or higher (F0-F2 vs. F3-F4) was 0.865, 0.824, 0.708, 0.789 and 0.828, respectively. Conclusions: RTE is useful for diagnosis of liver fibrosis, regardless of stage, in patients with chronic viral hepatitis.


Oncology | 2013

Novel Image Analysis Method Using Ultrasound Elastography for Noninvasive Evaluation of Hepatic Fibrosis in Patients with Chronic Hepatitis C

Kenji Fujimoto; Michio Kato; Masatoshi Kudo; Norihisa Yada; Tsuyoshi Shiina; Kazuomi Ueshima; Yukinori Yamada; Tetsushi Ishida; Masayoshi Azuma; Masaru Yamasaki; Keiji Yamamoto; Norio Hayashi; Tetsuo Takehara

It has been established that the long-term infection of chronic hepatitis C leads to the increased risk of hepatic fibrosis and hepatocellular carcinoma. Currently, histological diagnosis by invasive and painful liver biopsy is the gold standard for evaluating the hepatic fibrosis stage. Because of a side effect or patient inability to cope with the pain, it is difficult to assess the fibrosis stage frequently using liver biopsy. Recently, instead of liver biopsy, many articles have been published showing the usefulness of ultrasound elastography to evaluate the stage of hepatic fibrosis. We also reported the usefulness of real-time tissue elastography (RTE) for liver fibrosis staging in 2007. However, in our previous report, fibrosis classification was performed manually and the number of patients involved was also small. In the current study, the fibrosis staging is performed automatically using software by characterizing the elastography images. We have also increased the number of patients from 64 to 310. Thus, the aim of this study is to increase objectivity by using a newly developed automatic analysis method. We obtain the Liver Fibrosis Index (LFI), which is calculated from image features of RTE images, using multiple regression analysis performed on clinical data of 310 cases as the training data set. The correlation coefficient obtained between the LFI and the stage of hepatic fibrosis was r = 0.68, and significant differences exist between all stages of fibrosis (p < 0.001). Our new method seems promising since it has the ability to diagnose fibrosis even in the presence of inflammation.


Digestive Diseases | 2011

Des-γ-Carboxyprothrombin May Be a Promising Biomarker to Determine the Therapeutic Efficacy of Sorafenib for Hepatocellular Carcinoma

Kazuomi Ueshima; Masatoshi Kudo; Masahiro Takita; Tomoyuki Nagai; Chie Tatsumi; Taisuke Ueda; Satoshi Kitai; Emi Ishikawa; Norihisa Yada; Tatsuo Inoue; Satoru Hagiwara; Yasunori Minami; Hobyung Chung; Toshiharu Sakurai

Objective: The purpose of this study was to evaluate the role of des-γ-carboxyprothrombin (DCP) as a marker for the efficacy of sorafenib therapy for hepatocellular carcinoma (HCC). Methods: Patients with advanced HCC treated with sorafenib were retrospectively evaluated, focusing on DCP levels and clinical characteristics. Results: 50 patients with advanced HCC were treated with sorafenib alone. In 25 of these patients, the serum levels of DCP were evaluated twice (pretreatment and within 2 weeks after starting therapy). The time to progression was significantly longer in patients in whom the DCP level at 2 weeks after starting sorafenib was ≧2-fold higher than the pretreatment levels, as compared with patients without an increase in DCP (p = 0.0296). Conclusions: The serum level of DCP is a surrogate marker for tissue hypoxia and can be a predictive marker to assess the tumor response to sorafenib therapy.


Journal of Medical Ultrasonics | 2013

JSUM ultrasound elastography practice guidelines: liver

Masatoshi Kudo; Tsuyoshi Shiina; Fuminori Moriyasu; Hiroko Iijima; Ryosuke Tateishi; Norihisa Yada; Kenji Fujimoto; Hiroyasu Morikawa; Masashi Hirooka; Yasukiyo Sumino; Takashi Kumada

In diffuse liver disease, it is extremely important to make an accurate diagnosis of liver fibrosis prior to determining indications for therapy or predicting treatment outcome and malignant potential. Although liver biopsy has long been the gold standard in the diagnosis of liver fibrosis, it is still an invasive method. In addition, the sampling error is an intrinsic problem of liver biopsy. Non-invasive serological methods for the diagnosis of liver fibrosis can be affected by factors unrelated to the liver. Recently, after the introduction of FibroScan, it became possible to measure liver fibrosis directly and non-invasively by elastography, which has attracted attention as a non-invasive imaging diagnostic tool for liver fibrosis. In addition, real-time tissue elastography is currently being used to conduct clinical trials at many institutions. Moreover, virtual touch quantification enables the observation of liver stiffness at any location by simply observing B-mode images. Furthermore, the recently developed ShearWave elastography visualizes liver stiffness on a color map. Elastography is thought to be useful for all types of diffuse liver diseases. Because of its association with portal hypertension and liver carcinogenesis, elastography is expected to function as a novel prognostic tool for liver disease. Although various elastographic devices have been developed by multiple companies, each device has its own measurement principle, method, and outcome, creating confusion in clinical settings. Therefore, it is extremely important to understand the characteristics of each device in advance. The objective of this guideline, which describes the characteristics of each device based on the latest knowledge, is for all users to be able to make the correct diagnosis of hepatic fibrosis by ultrasound elastography.


Digestive Diseases | 2011

Oral Branched-Chain Amino Acid Granules Reduce the Incidence of Hepatocellular Carcinoma and Improve Event-Free Survival in Patients with Liver Cirrhosis

Sosuke Hayaishi; Hobyung Chung; Masatoshi Kudo; Emi Ishikawa; Masahiro Takita; Taisuke Ueda; Satoshi Kitai; Tatsuo Inoue; Norihisa Yada; Satoru Hagiwara; Yasunori Minami; Kazuomi Ueshima

Background: It has been reported that branched-chain amino acid (BCAA) supplementation can improve nutritional status and prevent liver-related complications in patients with decompensated cirrhosis. We investigated the effects of oral BCAA supplementation on the incidence of hepatocellular carcinoma (HCC) and liver-related events in patients with compensated and decompensated cirrhosis. Methods: We enrolled 211 patients with cirrhosis including 152 patients with Child-Pugh A cirrhosis, but no history of HCC. Of these, 56 received oral administration of 12 g/day BCAA for ≧6 months (BCAA group), and 155 were followed-up without BCAA treatment (control group). The HCC occurrence and event-free survival rates were compared between the two groups. We used a propensity score analysis to overcome selection bias of this retrospective analysis. Results: The HCC occurrence rate was significantly lower and event-free survival rate was significantly higher in the BCAA group than in the control group. Multivariate analyses showed BCAA supplementation was significantly associated with reduced incidence of HCC (hazard ratio (HR) 0.416, 95% confidence interval (CI) 0.216–0.800, p = 0.0085). BCAA supplementation also reduced the incidence of liver-related events in patients with Child-Pugh A cirrhosis, although the difference did not reach statistical significance (HR 0.585, 95% CI 0.336–1.017, p = 0.0575). Conclusions: Oral BCAA supplementation is associated with reduced incidence of HCC in patients with cirrhosis and seems to prevent liver-related events in patients with Child-Pugh A cirrhosis.


Oncology | 2010

Radiofrequency Ablation for Hepatocellular Carcinoma: Assistant Techniques for Difficult Cases

Tatsuo Inoue; Yasunori Minami; Hobyung Chung; Sousuke Hayaishi; Taisuke Ueda; Chie Tatsumi; Masahiro Takita; Satoshi Kitai; Kinuyo Hatanaka; Emi Ishikawa; Norihisa Yada; Satoru Hagiwara; Kazuomi Ueshima; Masatoshi Kudo

Purpose: To confirm the safety and effectiveness of techniques to assist radiofrequency ablation (RFA) for difficult cases, we retrospectively evaluated successful treatment rates, early complications and local tumor progressions. Patients and Methods: Between June 1999 and April 2009, a total of 341 patients with 535 nodules were treated as difficult cases. Artificial pleural effusion assisted ablation was performed on 64 patients with 82 nodules. Artificial ascites-assisted ablation was performed on 11 patients with 13 nodules. Cooling by endoscopic nasobiliary drainage (ENBD) tube-assisted ablation was performed on 6 patients with 8 nodules. When the tumors were not well visualized with conventional B-mode ultrasonography (US), contrast-enhanced US-assisted ablation with Levovist® or Sonazoid® or virtual CT sonography-assisted ablation was performed. Contrast-enhanced US-assisted ablation was performed on 139 patients with 224 nodules and virtual CT sonography-assisted ablation was performed on 121 patients with 209 nodules. Results: In total, complete ablation was achieved in 514 of 535 (96%) nodules in difficult cases. For RFA with artificial pleural effusion, artificial ascites and ENBD, complete response was confirmed in all cases. For contrast-enhanced US- and CT sonography-assisted ablation, complete response was 95%. Early complications were recognized in 24 cases (4.5%). All cases recovered with no invasive treatment. Local tumor recurrence was investigated in 377 nodules of 245 patients, and 69 (18%) nodules were positive. Tumor recurrences in each assisted technique were 14.7% in artificial pleural effusion cases, 7% in artificial ascites, 12.5% in ENBD tube cases, 31% in virtual CT sonography, and 8.5% in contrast-enhanced US. Conclusion: Although local tumor progression needs to be carefully monitored, assisted techniques of RFA for difficult cases are well tolerated and expand the indications of RFA.


Digestive Diseases | 2013

Reactive Oxygen Species Induce Epigenetic Instability through the Formation of 8-Hydroxydeoxyguanosine in Human Hepatocarcinogenesis

Naoshi Nishida; Tadaaki Arizumi; Masahiro Takita; Satoshi Kitai; Norihisa Yada; Satoru Hagiwara; Tatsuo Inoue; Yasunori Minami; Kazuomi Ueshima; Toshiharu Sakurai; Masatoshi Kudo

Chronic hepatitis C (CHC) triggers oxidative stress and contributes to the emergence of hepatocellular carcinoma (HCC). We previously reported that tumor suppressor gene (TSG) methylation is a critical factor during the early stages of hepatocarcinogenesis. In this study, we clarify the association between oxidative stress and epigenetic alterations during hepatocarcinogenesis. We examined DNA oxidation and methylation profiles in 128 liver biopsy samples from CHC patients. The DNA oxidation and methylated TSG numbers were quantified using immunohistochemical analysis of 8-hydroxydeoxyguanosine (8-OHdG) and quantitative PCR for 11 TSGs, respectively. The quantitative chromatin immunoprecipitation-PCR (ChIP-qPCR) assay in HepG2 and fetal liver Hc cells treated with H2O2 was used to quantify trimethyl-H3K4, acetylated-H4K16 (an active chromatin marker), trimethyl-H3K27 (a repressive chromatin marker) and 8-OHdG. We analyzed 30 promoters of 25 different TSGs by qPCR. The high levels of 8-OHdG was the only variable that was significantly associated with the increased number of methylated TSGs in CHC (p < 0.0001). The ChIP-qPCR revealed that after H2O2 treatment of the cell lines, the 8-OHdG-bound promoters showed a modification from an active chromatin (trimethyl-H3K4 and acetylated-H4K16 dominant) to a repressive chromatin (trimethyl-H3K27 dominant) status. We conclude that oxidative stress alters the chromatin status, which leads to abnormal methylation of TSGs, and contributes to hepatocarcinogenesis in CHC patients.

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