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Dive into the research topics where Hirokazu Kawai is active.

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Featured researches published by Hirokazu Kawai.


Cancer | 2003

Telomere length variation and maintenance in hepatocarcinogenesis

Takashi Yokota; Takeshi Suda; Masato Igarashi; Takashi Kuroiwa; Nobuo Waguri; Hirokazu Kawai; Yusaku Mita; Yutaka Aoyagi

Despite the recent discovery of interchromosomal telomere length variation, a role for heterogeneity in telomere maintenance has yet to be established. This study investigated the significance of telomere length variation between chromosomes with respect to the association of cancer progression and telomere length regulation.


Hepatology Research | 2009

Progress toward liver-based gene therapy.

Takeshi Suda; Kenya Kamimura; Tomoyuki Kubota; Yasushi Tamura; Masato Igarashi; Hirokazu Kawai; Yutaka Aoyagi; Dexi Liu

The liver is involved in the synthesis of serum proteins, regulation of metabolism and maintenance of homeostasis and provides a variety of opportunities for gene therapy. The enriched vasculature and blood circulation, fenestrated endothelium, abundant receptors on the plasma membranes of the liver cells, and effective transcription and translation machineries in the hepatocytes are some unique features that have been explored for delivery, and functional analysis, of genetic sequences in the liver. Both viral and non‐viral methods have been developed for effective gene delivery and liver‐based gene therapy. This review describes the fundamentals of gene delivery, and the preclinical and clinical progress that has been made toward gene therapy using the liver as a target.


Hepatology Research | 2007

Fucosylated fraction of alpha‐fetoprotein, L3, as a useful prognostic factor in patients with hepatocellular carcinoma with special reference to low concentrations of serum alpha‐fetoprotein

Makoto Kobayashi; Takashi Kuroiwa; Takeshi Suda; Yasushi Tamura; Hirokazu Kawai; Masato Igarashi; Yasuo Fukuhara; Yutaka Aoyagi

Background:  The aim of the present study was to establish L3 fraction before initial treatment as a useful prognostic factor in a prospective fashion in hepatocellular carcinoma (HCC) where the alpha‐fetoprotein (AFP) was very low.


World Journal of Hepatology | 2011

Multicentric occurrence of hepatocellular carcinoma with nonalcoholic steatohepatitis

Hirokazu Kawai; Minoru Nomoto; Takeshi Suda; Kenya Kamimura; Atsunori Tsuchiya; Yasushi Tamura; Masahiko Yano; Masaaki Takamura; Masato Igarashi; Toshifumi Wakai; Satoshi Yamagiwa; Yasunobu Matsuda; Shogo Ohkoshi; Isao Kurosaki; Yoshio Shirai; Masahiko Okada; Yutaka Aoyagi

AIM To reveal the manner of hepatocellular carcinoma (HCC) development in patients with nonalcoholic steatohepatitis (NASH) focusing on multicentric occurrence (MO) of HCC. METHODS We compared clinicopathological characteristics between patients with and without MO of HCC arising from NASH background. The clinical features were implicated with reference to the literature available. RESULTS MO of HCC was identified with histological proof in 4 out of 12 patients with NASH-related HCC (2 males and 2 females). One patient had synchronous MO; an advanced HCC, two well-differentiated HCCs and a dysplastic nodule, followed by the development of metachronous MO of HCC. The other three patients had multiple advanced HCCs accompanied by a well-differentiated HCC or a dysplastic nodule. Of these three patients, one had synchronous MO, one had metachronous MO and the other had both synchronous and metachronous MO. There were no obvious differences between the patients with or without MO in terms of liver function tests, tumor markers and anatomical extent of HCC. On the other hand, all four patients with MO of HCC were older than 70 years old and had the comorbidities of obesity, type 2 diabetes mellitus (T2DM), hypertension and cirrhosis. Although these conditions were not limited to MO of HCC, all the conditions were met in only one of eight patients without MO of HCC. Thus, concurrence of these conditions may be a predisposing situation to synchronous MO of HCC. In particular, old age, T2DM and cirrhosis were suggested to be prerequisite for MO because these factors were depicted in common among two other cases with MO of HCC under NASH in the literature. CONCLUSION The putative predisposing factors and necessary preconditions for synchronous MO of HCC in NASH were suggested in this study. Further investigations are required to clarify the accurate prevalence and predictors of MO to establish better strategies for treatment and prevention leading to the prognostic improvement in NASH.


World Journal of Gastroenterology | 2015

Advances in understanding and treating liver diseases during pregnancy: A review.

Kenya Kamimura; Hiroyuki Abe; Hirokazu Kawai; Hiroteru Kamimura; Yuji Kobayashi; Minoru Nomoto; Yutaka Aoyagi; Shuji Terai

Liver disease in pregnancy is rare but pregnancy-related liver diseases may cause threat to fetal and maternal survival. It includes pre-eclampsia; eclampsia; haemolysis, elevated liver enzymes, and low platelets syndrome; acute fatty liver of pregnancy; hyperemesis gravidarum; and intrahepatic cholestasis of pregnancy. Recent basic researches have shown the various etiologies involved in this disease entity. With these advances, rapid diagnosis is essential for severe cases since the decision of immediate delivery is important for maternal and fetal survival. The other therapeutic options have also been shown in recent reports based on the clinical trials and cooperation and information sharing between hepatologist and gynecologist is important for timely therapeutic intervention. Therefore, correct understandings of diseases and differential diagnosis from the pre-existing and co-incidental liver diseases during the pregnancy will help to achieve better prognosis. Therefore, here we review and summarized recent advances in understanding the etiologies, clinical courses and management of liver disease in pregnancy. This information will contribute to physicians for diagnosis of disease and optimum management of patients.


World Journal of Gastroenterology | 2013

Active treatments are a rational approach for hepatocellular carcinoma in elderly patients

Takeshi Suda; Aiko Nagashima; Shyunsaku Takahashi; Tsutomu Kanefuji; Kenya Kamimura; Yasushi Tamura; Masaaki Takamura; Masato Igarashi; Hirokazu Kawai; Satoshi Yamagiwa; Minoru Nomoto; Yutaka Aoyagi

AIM To determine whether an active intervention is beneficial for the survival of elderly patients with hepatocellular carcinoma (HCC). METHODS The survival of 740 patients who received various treatments for HCC between 1983 and 2011 was compared among different age groups using Cox regression analysis. Therapeutic options were principally selected according to the clinical practice guidelines for HCC from the Japanese Society of Hepatology. The treatment most likely to achieve regional control capability was chosen, as far as possible, in the following order: resection, radiofrequency ablation, percutaneous ethanol injection, transcatheter arterial chemoembolization, transarterial oily chemoembolization, hepatic arterial infusion chemotherapy, systemic chemotherapy including molecular targeting, or best supportive care. Each treatment was used alone, or in combination, with a clinical goal of striking the best balance between functional hepatic reserve and the volume of the targeted area, irrespective of their age. The percent survival to life expectancy was calculated based on a Japanese national population survey. RESULTS The median ages of the subjects during each 5-year period from 1986 were 61, 64, 67, 68 and 71 years and increased significantly with time (P < 0.0001). The Child-Pugh score was comparable among younger (59 years of age or younger), middle-aged (60-79 years of age), and older (80 years of age or older) groups (P = 0.34), whereas the tumor-node-metastasis stage tended to be more advanced in the younger group (P = 0.060). Advanced disease was significantly more frequent in the younger group compared with the middle-aged group (P = 0.010), whereas there was no difference between the middle-aged and elderly groups (P = 0.75). The median survival times were 2593, 2011, 1643, 1278 and 1195 d for 49 years of age or younger, 50-59 years of age, 60-69 years of age, 70-79 years of age, or 80 years of age or older age groups, respectively, whereas the median percent survival to life expectancy were 13.9%, 21.9%, 24.7%, 25.7% and 37.6% for each group, respectively. The impact of age on actual survival time was significant (P = 0.020) with a hazard ratio of 1.021, suggesting that a 10-year-older patient has a 1.23-fold higher risk for death, and the overall survival was the worst in the oldest group. On the other hand, when the survival benefit was evaluated on the basis of percent survival to life expectancy, age was again found to be a significant explanatory factor (P = 0.022); however, the oldest group showed the best survival among the five different age groups. The youngest group revealed the worst outcomes in this analysis, and the hazard ratio of the oldest against the youngest was 0.35 for death. The survival trends did not differ substantially between the survival time and percent survival to life expectancy, when survival was compared overall or among various therapeutic interventions. CONCLUSION These results suggest that a therapeutic approach for HCC should not be restricted due to patient age.


Cancer Medicine | 2013

A safe and effective dose of cisplatin in hepatic arterial infusion chemotherapy for hepatocellular carcinoma

Akihiko Osaki; Takeshi Suda; Kenya Kamimura; Atsunori Tsuchiya; Yasushi Tamura; Masaaki Takamura; Masato Igarashi; Hirokazu Kawai; Satoshi Yamagiwa; Yutaka Aoyagi

Cisplatin (CDDP) is an anticancer agent that is commonly used in hepatic arterial infusion (HAI) chemotherapy for hepatocellular carcinoma (HCC). This study aimed to clarify the safe and effective dose of CDDP in HAI for HCC. The hypervascular area was measured in 42 HCCs before and after HAI with CDDP. Serum platinum concentration was quantified in the peripheral and/or middle hepatic veins by atomic absorption spectrometry. The relation between the HCC response and CDDP dose was statistically analyzed. The multiple HCC nodules in an individual case generally demonstrated the same response to CDDP. The free‐platinum concentration stayed relatively constant in the hepatic vein during HAI followed by a rapid decline, while total‐platinum gradually increased then slowly disappeared over several days. After CDDP‐HAI, 15 HCCs shrunk and 27 HCCs grew. The reduction rate in the shrunken nodules was tended to be correlated with CDDP dose after standardization with the target liver volume. On the other hand, the growth rate of the enlarged HCCs was significantly correlated with CDDP dose after normalization with creatinine clearance. These data support a recommendation of CDDP‐HAI infusion where the amount of CDDP (mg) administered is less than patient creatinine clearance (mL/min/1.73 m2) upon an assumption of HCC doubling time of 90 days, and the targeted liver is smaller than 200 times the CDDP dose (mg). A further analysis is required to define appropriate injection speeds.


PLOS ONE | 2017

Long-term efficacy and safety of nalfurafine hydrochloride on pruritus in chronic liver disease patients: Patient-reported outcome based analyses

Kenya Kamimura; Takeshi Yokoo; Hiroteru Kamimura; Akira Sakamaki; Satoshi Abe; Atsunori Tsuchiya; Masaaki Takamura; Hirokazu Kawai; Satoshi Yamagiwa; Shuji Terai

Background and aim Among various symptoms accompanied with chronic liver disease, pruritus affects the quality of life of patients, causing physical and mental stress, and worsens hepatic function. Recently, κ-opioid receptor agonist, nalfurafine hydrochloride was approved to treat central pruritus in patients with liver disease in Japan. This study aimed to assess the long-term efficacy and safety of nalfurafine hydrochloride on pruritus in chronic liver disease patients. Methods A patient-reported outcome using questionnaire-based methods was used for 41 liver disease patients with or without pruritus symptoms. Nalfurafine hydrochloride (2.5 μg/day) was orally administered to 18 patients suffering from pruritus symptoms and whose current treatment was not effective. The same questionnaires and visual analogue scales (VAS) were repeatedly followed up for the patients for the entire follow-up period, and biochemical analyses were performed to evaluate the safety of the treatment. Results Pruritus completely disappeared in seven of 18 cases, and VAS scores showed a decreasing trend over time from the start of nalfurafine hydrochloride administration in all patients who received the medication. Among 11 patients who were followed up for more than 12 weeks, nine patients showed continuous improvement of symptoms, and this progress was still apparent at ≥20 weeks after starting administration (p < 0.0001). The medication was discontinued in four patients because of progression of primary disease, high cost, oral dryness, and anemia. No significant toxicity was observed on the serum biochemical analyses. Conclusions Nalfurafine hydrochloride contributed to long-term suppression of pruritus without significant safety problems.


BMC Gastroenterology | 2012

Phase I study of miriplatin combined with transarterial chemotherapy using CDDP powder in patients with hepatocellular carcinoma

Kenya Kamimura; Takeshi Suda; Yasushi Tamura; Masaaki Takamura; Takeshi Yokoo; Masato Igarashi; Hirokazu Kawai; Satoshi Yamagiwa; Minoru Nomoto; Yutaka Aoyagi

BackgroundThere is no standard therapeutic procedure for the hepatocellular carcinoma (HCC) in patients with poor hepatic reserve function. With the approval of newly developed chemotherapeutic agent of miriplatin, we have firstly conducted the phase I study of CDDP powder (DDP-H) and miriplatin combination therapy and reported its safety and efficacy for treating unresectable HCC in such cases. To determine the maximum tolerated dose (MTD) and dose-limiting toxicity (DLT) for the combination of transarterial oily chemoembolization (TOCE) and transarterial chemotherapy (TAC) using miriplatin and DDP-H for treating unresectable hepatocellular carcinoma (HCC).MethodsTransarterial chemotherapy using DDP-H was performed through the proper hepatic artery targeting the HCC nodules by increasing the dose of DDP-H (35–65 mg/m2) followed by targeting the HCC nodules by transarterial oily chemoembolization with miriplatin.ResultsA total of nine patients were enrolled in this study and no DLT was observed with any dose of DDP-H in all cases in whom 80 mg (median, 18–120) miriplatin was administered. An anti-tumour efficacy rating for partial response was obtained in one patient, while a total of four patients (among eight evaluated) showed stable disease response, leading to 62.5% of disease control rate. The pharmacokinetic results showed no further increase in plasma platinum concentration following miriplatin administration.ConclusionOur results suggest that a combination of DDP-H and miriplatin can be safely administered up to their respective MTD for treating HCC.Trial registrationThis study was registered with the University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR000003541).


Clinics and Research in Hepatology and Gastroenterology | 2015

Diagnostic imaging of hepatic lymphoma.

Hiroyuki Abe; Kenya Kamimura; Hirokazu Kawai; Hiroteru Kamimura; Koji Domori; Yuji Kobayashi; Minoru Nomoto; Yutaka Aoyagi

Hepatic lymphoma is a rare disease with poor prognosis because of delayed diagnosis. The disease comprises primary, metastatic, and intravascular hepatic lymphomas. The pathological characteristics of lymphomas differ contributing to difficulty in early diagnosis. Early diagnosis and appropriate treatment result in improved prognosis; therefore, diagnostic radiology and its development with various contrast agents are critical for improving disease outcomes. Herein, we review hepatic lymphomas and summarize the results of imaging studies in correlation with pathological characteristics. The information provided will help physicians in early diagnosis and thereby improving prognosis.

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