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Dive into the research topics where Hirokazu Shiozawa is active.

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Featured researches published by Hirokazu Shiozawa.


World Journal of Gastroenterology | 2015

Sulforaphane-rich broccoli sprout extract improves hepatic abnormalities in male subjects

Masahiro Kikuchi; Yusuke Ushida; Hirokazu Shiozawa; Rumiko Umeda; Kota Tsuruya; Yudai Aoki; Hiroyuki Suganuma; Yasuhiro Nishizaki

AIM To evaluate effects of dietary supplementation of sulforaphane (SF)-rich broccoli sprout (BS) extract on hepatic abnormalities in Japanese male participants. METHODS In a randomized, placebo-controlled, double blind trial, male participants with fatty liver received either BS capsules containing glucoraphanin [GR; a precursor of SF (n = 24)] or placebo (n = 28) for 2 mo. Liver function markers, serum levels of aspartate and alanine aminotransferases (AST and ALT, respectively) and γ-glutamyl transpeptidase (γ-GTP) and an oxidative stress marker, urinary levels of 8-hydroxydeoxyguanosine (8-OHdG), were measured and compared in participants before and after the trial period. In an animal model, chronic liver failure was induced in Sprague-Dawley rats by successive intraperitoneal injection with N-nitrosodimethylamine (NDMA) for 4 wk. Concomitantly, rats received AIN-76 diets supplemented with or without BS extract. Thereafter, rats were sacrificed, and their sera and livers were collected to measure serum liver function markers and hepatic levels of thiobarbituric acid reactive substances (TBARS) levels and hepatic glutathione S-transferase (GST) activity, a prototypical phase 2 antioxidant enzyme. RESULTS Dietary supplementation with BS extract containing SF precursor GR for 2 mo significantly decreased serum levels of liver function markers, ALT [median (interquartile range), before: 54.0 (34.5-79.0) vs after supplementation: 48.5 (33.3-65.3) IU/L, P < 0.05] and γ-GTP [before: 51.5 (40.8-91.3) vs after: 50.0 (37.8-85.3) IU/L, P < 0.05], as well as the alkali phosphatase activity. Placebo showed no significant effects on the markers. The urinary level of 8-OHdG, an established oxidative stress marker, was significantly reduced in participants who had received BS capsules but not the placebo [before: 6.66 (5.51-9.03) vs after: 5.49 (4.89-6.66) ng/mg-creatinine, P < 0.05]. The reduction of urinary 8-OHdG was significantly correlated with decreased levels of both ALT and γ-GTP [∆8-OHdG and ∆ALT: Spearman r (r) 0.514 and P = 0.012, ∆8-OHdG and ∆γ-GTP: r = 0.496 and P = 0.016]. Intake of BS extract prevented NDMA-induced chronic liver failure in rats, which was attributable to the suppression of the increase in TBARS through induction of hepatic phase 2 antioxidant enzymes including hepatic GST (86.6 ± 95.2 vs 107.8 ± 7.7 IU/g, P < 0.01). CONCLUSION Dietary supplementation with BS extract containing the SF precursor GR is likely to be highly effective in improving liver function through reduction of oxidative stress.


Hepatitis Research and Treatment | 2010

Differential Impact of Adherence to Pegylated Interferon and Ribavirin in the Treatment of Genotype 1 High Viral Titer Chronic Hepatitis C

Makoto Numata; Tatehiro Kagawa; Seiichiro Kojima; Shunji Hirose; Naruhiko Nagata; Koichi Shiraishi; Norihito Watanabe; Hirokazu Shiozawa; Yasuhiro Nishizaki; Shigeyuki Motegi; Shinji Takashimizu; Junichiro Kamochi; Mitsuru Wasada; Takashi Ohno; Yoshihiro Tei; Atsushi Nakano; Takuji Yamada; Kazuhiro Atsukawa; Tetsu Watanabe; Tetsuya Mine

To clarify the impact of adherence, we treated 122 genotype 1 high viral titer chronic hepatitis C patients with pegylated interferon (peg-IFN) and ribavirin for 48 weeks at nine referral hospitals, and evaluated the prognostic factors with a focus on the adherence to the treatment. This study included 68 (55.7%) treatment-naïve patients and 54 (44.3%) patients who did not respond to the previous treatment. Multivariate analysis revealed adherence to peg-IFN and ribavirin as the only significant predictor. Sustained virological response (SVR) rate was 72.2%, 19.0%, and 27.3% in patients given ≥80%, 60%–80%, and <60% dose peg-IFN, respectively, and was 68.6%, 41.2%, and 5.3% in those given ≥80%, 60%–80%, and <60% dose ribavirin, respectively. SVR rate sharply fell when exposure to peg-IFN was below 80% whereas it decreased in a stepwise manner as for ribavirin. Therefore, ≥80% of peg-IFN and as much as possible dose of ribavirin are desired to achieve SVR in the treatment of genotype 1 high viral titer chronic hepatitis C.


Digestion | 2017

Yogurt Containing Lactobacillus gasseri Mitigates Aspirin-Induced Small Bowel Injuries: A Prospective, Randomized, Double-Blind, Placebo-Controlled Trial

Takayoshi Suzuki; Aya Masui; Jun Nakamura; Hirokazu Shiozawa; Jun Aoki; Hirohiko Nakae; Shingo Tsuda; Jin Imai; Ozawa Hideki; Masashi Matsushima; Tetsuya Mine; Akira Tamura; Toshihiro Ohtsu; Yukio Asami; Atsushi Takagi

Background: Although there is evidence about the beneficial effects of probiotics, their effects on aspirin-induced small bowel injuries have not been well examined. We evaluated the effects of the probiotic Lactobacillus gasseri OLL2716 (LG) on aspirin-induced small intestinal lesions, such as ulcers, erosions, reddened lesions, and bleeding. Summary: This study enrolled 64 patients who received aspirin for more than 1 month and provided written informed consent to be part of the study. The patients received 112 ml of yogurt containing LG or placebo twice daily for 6 weeks. Small bowel injuries were evaluated by capsule endoscopy before and after consuming the yogurt. The effect of LG on patient symptoms was also assessed using the Frequency Scale for the Symptoms of Gastroesophageal Reflux Disease (FSSG) and Gastrointestinal Symptom Rating Scale (GSRS) questionnaires before and after 6 weeks of treatment. There was no significant difference in any baseline characteristics and the number of small bowel mucosal breaks between the 2 groups. In contrast with the placebo group, the LG group had significantly fewer small bowel mucosal breaks and reddened lesions after 6 weeks (p < 0.01). The FSSG and GSRS scores were also significantly improved in the LG group but not in the placebo group. Key Messages: This double-blind, placebo-controlled study found that LG may be useful in reducing aspirin-induced small bowel injuries and in mitigating gastrointestinal symptoms.


Clinical Journal of Gastroenterology | 2014

Acute portal vein thrombosis due to chronic relapsing pancreatitis: a fistula between a pancreatic pseudocyst and the splenic vein

Masahiro Kikuchi; Yasuhiro Nishizaki; Kota Tsuruya; Ikuko Hamada; Toru Higashi; Keiko Sakuma; Hirokazu Shiozawa; Jun Aoki; Rena Nagashima; Jun Koizumi; Yoshitaka Arase; Koichi Shiraishi; Masashi Matsushima; Tetsuya Mine

Abstract Portal vein thrombosis (PVT) is a relatively common complication in patients with liver cirrhosis, but several other causes might play an important role in PVT pathogenesis. We present a case of alcoholic chronic pancreatitis complicated by acute extensive PVT. The patient was managed conservatively with danaparoid sodium at first, but the thrombosis gradually extended. We then tried radiological intervention using the direct transhepatic and transjugular intrahepatic postsystemic shunt approaches. Although we were able to successfully catheterize the percutaneous transhepatic portal vein (PTP), we could not achieve recanalization of the portal vein. Therefore, PTP catheterization and systemic intravenous infusion of urokinase and heparin was performed to prevent further progression of the thrombosis and cavernous transformation was finally achieved. Computed tomography (CT) and magnetic resonance cholangiopancreatography revealed a pancreatic stone which had possibly induced dilatation of the tail duct and formation of a pancreatic pseudocyst and caused intractable pancreatitis. We performed endoscopic retrograde cholangiopancreatography and placed a stent in the pancreatic duct, which completely cured the pancreatitis. Retrospectively, the previous CT with curved multi-planar reconstruction was reviewed and a fistula was detected between the pancreatic pseudocyst and splenic vein. We concluded that the etiology of the PVT was not only inflammatory extension from pancreatitis but also a fistula between the pancreatic duct and the splenic vein.


Hepatology Research | 2008

Eight‐week oral administration of meloxicam, a non‐steroidal anti‐inflammatory drug, prevents dose reduction of pegylated interferon α‐2a in the treatment of chronic hepatitis C

Tatehiro Kagawa; Hirokazu Shiozawa; Seiichiro Kojima; Shinji Takashimizu; Naruhiko Nagata; Makoto Numata; Fumitoshi Morino; Yasuhiro Nishizaki; Kaori Mochizuki; Norihito Watanabe; Tetsu Watanabe; Shohei Matsuzaki; Tetsuya Mine

Aim:  We conducted a trial to evaluate whether eight‐week oral administration of meloxicam, a non‐steroidal anti‐inflammatory drug, would decrease the rate of the patients who required dose reduction of pegylated interferon α‐2a in the treatment of chronic hepatitis C.


Hepatology Research | 2012

Weight‐based high‐ and low‐dose ribavirin in combination with peginterferon α‐2b therapy for genotype 2 chronic hepatitis C: A randomized trial

Tatehiro Kagawa; Seiichiro Kojima; Koichi Shiraishi; Shinji Takashimizu; Naruhiko Nagata; Hirokazu Shiozawa; Yasuhiro Nishizaki; Akihiko Ikeda; Yoshihiro Tei; Kazuhiro Atsukawa; Junichiro Kamochi; Mitsuru Wasada; Makoto Numata; Yoshitaka Arase; Shunji Hirose; Takuji Yamada; Yasuo Hata; Norihito Watanabe; Toshio Morizane; Tetsuya Mine

Aim:  The optimal ribavirin dose in the treatment of patients infected with hepatitis C virus (HCV) genotype 2 remains to be elucidated. We aimed to seek the optimal ribavirin dose required for this genotype in a randomized trial.


Journal of Gastroenterology | 2003

Hemophagocytic syndrome in ileum-origin B-cell lymphoma

Shigeyuki Motegi; Yasuhiro Nishizaki; Chikashi Muramatsu; Hiroyuki Nakamura; Fuminori Kobayashi; Hirokazu Shiozawa; Junichiro Kamochi; Masaru Itakura; Makoto Shibuya; Tetsuhei Ogawa; Shohei Matsuzaki

A 56 year-old-man was admitted due to upper abdominal tumor and was diagnosed as having stage IVb diffuse B-cell malignant lymphoma that originally developed in the terminal ileum. The first and the second administrations of CHOP (cyclophosphamide, 750 mg/m2; adriamycin, 50 mg/m2; vincristine, 1.4 mg/m2; and prednisolone, 100 mg/day) therapy were effective; however, the third course of therapy was postponed because of an episode of massive hematochezia. After this episode, lymph nodes began to enlarge and progressive pancytopenia occurred. Bone marrow smear showed the proliferation of reactive histiocytic cells which phagocytized red blood cells, white blood cells, and platelets. B-cell lymphoma-associated hemophagocytic syndrome (B-LAHS) was diagnosed. This case is extremely rare because: (1) LAHS occurred in an ileum-origin B-cell lymphoma, and (2) LAHS developed during an interval after chemotherapy.


Hepatology Research | 2013

Meloxicam as an adjuvant to peginterferon-α-2a and ribavirin treatment for genotype 1 chronic hepatitis C: A randomized trial

Tatehiro Kagawa; Seiichiro Kojima; Koichi Shiraishi; Shunji Hirose; Yoshitaka Arase; Shinji Takashimizu; Norihito Watanabe; Naruhiko Nagata; Makoto Numata; Hirokazu Shiozawa; Yasuhiro Nishizaki; Mayu Toki; Teruji Sugita; Kijuro Nomura; Takashi Sakaguchi; Kazuhiro Atsukawa; Hiroto Tajima; Yoshihiro Tei; Tsutomu Inomoto; Tetsuya Mine

In this multicenter, randomized trial, we evaluated the effectiveness of meloxicam – a non‐steroidal anti‐inflammatory drug – as an adjuvant for enhancing antiviral efficacy and preventing neutropenia during the treatment of patients with genotype 1 chronic hepatitis C using peginterferon and ribavirin.


Alcoholism: Clinical and Experimental Research | 2002

Assessment of a Difference in ALDH2 Heterozygotes and Alcoholic Liver Injury

Naruhiko Nagata; Mineyoshi Hiyoshi; Hirokazu Shiozawa; Koichi Shiraishi; Norihito Watanabe; Michio Tsuda; Shohei Matsuzaki


総合健診 | 2012

Anti-aging health check-up system:— For the prevention of potentially progress aging related disadvantageous changes in elderly —

Yasuhiro Nishizaki; Akira Kubo; Ichiro Kuwahira; Emiko Kuroda; Noriko Nigou; Toshiharu Sueno; Shigeyuki Motegi; Hirokazu Shiozawa; Norihito Watanabe; Tetsuhei Ogawa; Ryuzaburo Tanino; Naoaki Ishii

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