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Featured researches published by Ryuya Shimoda.


Abdominal Imaging | 2005

Short-term complications of retrograde transvenous obliteration of gastric varices in patients with portal hypertension : effects of obliteration of major portosystemic shunts

Ryuya Shimoda; K. Horiuchi; S. Hagiwara; H. Suzuki; Y. Yamazaki; T. Kosone; T. Ichikawa; H. Arai; T. Yamada; T. Abe; Hitoshi Takagi; Masatomo Mori

The type, incidence, and severity of complications of balloon-occluded retrograde transvenous obliteration (B-RTO) for gastric varices should be precisely estimated. Complications were evaluated in 38 patients who had fundic gastric varices and 43 B-RTO procedures during injection of ethanolamine oleate (phase 1), within 4 h after injection (phase 2), 24 h after injection (phase 3), and from 24 h to 10 days after injection (phase 4). Endoscopic evaluation at 8 weeks showed resolution of gastric varices in 35 of 38 patients (92%) and smaller varices in the remaining three (8%). B-RTO caused transient hypertension in 35% of patients, hemoglobinuria in 49%, and fever in 33% during phases 1, 2, and 3, respectively. Pleural effusion, pulmonary infarction, ascites, gastric ulcers with unique appearance, localized mosaic-like change of gastric mucosa, and hemorrhagic portal hypertensive gastropathy were noted in phase 4. There were no fatalities. Lactate dehydrogenase, aspartate aminotransferase, and bilirubin increased on day 1. Each datum was retrieved within 7 days. The severity of lactate dehydrogenase elevation correlated significantly with the volume of infused ethanolamine oleate. Thus, B-RTO is a safe and effective management of fundic varices. However, short-term hemodynamic change after B-RTO may cause gastric mucosal damage. Pulmonary infarction and pleural effusion are potential complications.


Journal of Gastroenterology | 2005

Emergency balloon-occluded retrograde transvenous obliteration for gastric varices.

Hirotaka Arai; Takehiko Abe; Ryuya Shimoda; Hitoshi Takagi; Toshihiko Yamada; Masatomo Mori

BackgroundWe evaluated the efficacy of emergency balloon-occluded retrograde transvenous obliteration (B-RTO) performed within 24 h after initial hemostasis for the prevention of rebleeding from ruptured gastric varices.MethodsFrom December 1995 to March 2003, 11 patients who had undergone B-RTO within 24 h after the control of gastric variceal bleeding at Maebashi Red Cross Hospital were investigated. They were followed up for complete eradication, recurrence of varices, and rebleeding. Efficacy was determined by endoscopic examination and computed tomography.ResultsThe 4 patients with acute bleeding from ruptured gastric varices were treated with endoscopic therapy—endoscopic variceal ligation (EVL) in 2 patients, and clipping treatment in 2. Initial hemostasis was achieved in all 4; the other 7 patients had already stopped bleeding at endoscopy. After hemostasis was achieved, emergency B-RTO was immediately performed within 24 h and was successful in all 11 patients. Ten (90.9%) of the 11 gastric varices were obliterated and the other 1 (9.1%) was diminished in size. During the mean follow-up period of 1136 days, no rebleeding or recurrence as found. Four patients died during the follow-up period, but none died from variceal bleeding. Survival rates were 90.9% and 70.7%, respectively, at 1 year and 3 years. In 6 patients, development of esophageal varices appeared during the follow-up period, all of which were controlled by usual endoscopic therapy. No severe side effects were found after the B-RTO treatment.ConclusionsEmergency B-RTO is an effective treatment for the prevention of rebleeding from ruptured gastric varices.


Journal of Gastroenterology and Hepatology | 1998

Accidental transmission of HCV and treatment with interferon

Hitoshi Takagi; Masahiro Uehara; Satoru Kakizaki; Hitomi Takahashi; Jirou Takezawa; Kenji Kabeya; Ken Satoh; Akira Kojima; Shuichi Saito; Tatsuhiko Matsumoto; Yoshiaki Hashimoto; Takehiko Abe; Toshihiko Yamada; Kazuko Konaka; Ryuya Shimoda; Hisashi Takayama; Ken Takehara; Takeaki Nagamine; Masatomo Mori

Accidental transmission of contagious pathogens, especially hepatitis C virus (HCV), by needlestick or other means as an occupational hazard for medical staff is of concern. We retrospectively analysed cases of work‐related accidental injury with pathogens such as hepatitis B virus (HBV), HCV, syphilis and human immunodeficiency virus (HIV) reported to the centres for disease control at 15 hospitals (total 5776 beds) in the Gunma prefecture, Japan, from December 1990 to August 1993 (24.7 months). There were 416 such cases (16.8 cases/month), with an incidence of 0.2–3.5 accidents per month per hospital. Such accidents occurred in 297 (71.2%) nurses, 98 (23.5%) medical doctors, 13 (3%) laboratory technicians, four (1.0%) hospital maintenance workers, one (0.2%) assistant nurse, one secretary and two others. There were 323 (77.6%) injuries caused by needlestick, 42 (10.1%) from suture needles or surgical knife cuts, 17 (4.1%) from blood splatters from patients into the eyes or mouth, 10 (2.4%) from contact with injured skin and 24 (5.8%) simple skin contacts. Of the pathogens, 60.3% were HCV, 22.6% HBV, 5.8% syphilis, 0.7% HIV and 10.6% were of unknown origin. Four cases (1.6%) of HCV infection were found and treated with one or two courses of interferon therapy, and HCV was subsequently cleared. All four patients were cured with interferon therapy. None of the HBV‐injured cases resulted in infection, possibly because of prophylaxis with HB immunoglobulin and HB vaccine. No HIV or syphilis infection was contracted. In summary, chronic HCV infection acquired as an occupational hazard can be cured by appropriate treatment, such as with interferon, after early detection of the infection.


Biological Trace Element Research | 1997

THE POSSIBLE ROLE OF ZINC AND METALLOTHIONEIN IN THE LIVER ON THE THERAPEUTIC EFFECT OF IFN-ALPHA TO HEPATITIS C PATIENTS

Takeaki Nagamine; Hitoshi Takagi; Yoshiaki Hashimoto; Hisashi Takayama; Ryuya Shimoda; Naruo Nomura; Keiji Suzuki; Masatomo Mori; Katsuyuki Nakajima

We have studied zinc deficiency in hepatitis C patients (complete responder [C,R] 22, nonresponder [NR] 25) with relation to the therapeutic effect of interferon-α (IFN-α). Circadian variations in serum zinc levels were high in the morning (basal level) and then gradually decreased during the day in both chronic hepatitis C patients and healthy controls. Basal zinc levels in serum were significantly lower in chronic hepatitis C patients (73±3 μg/dL,n=12) than in controls (93±5 μg/dL). An injection of 10 MU of IFN-α to hepatitis C patients augmented the serum zinc reductions, up to 40% in 8 h. Serum cortisol levels were significantly elevated 8 h (25.6±2.3 μg/dL) after IFN-α dose. Forty-seven chronic hepatitis C patients were treated with IFN-α for 24 wk, and serum zinc and copper levels were determined 12 and 24 wk during and after the completion of IFN-α therapy. Serum zinc levels and zinc/copper ratio were higher in CRs than in NRs to IFN therapy at each time-point. Hepatic metallothionein staining became prominent after IFN therapy in most of CRs, whereas it diminished NRs. These data suggest that nutritional status of zinc influences the effect of IFN on hepatitis C patients.


Journal of Gastroenterology | 2002

Simple liver cyst with spontaneous regression.

Hirotaka Arai; Takeaki Nagamine; Hideyuki Suzuki; Ryuya Shimoda; Takehiko Abe; Toshihiko Yamada; Hitoshi Takagi; Masatomo Mori

We report a-55-year-old woman with spontaneous regression of simple liver cyst. The size of the cyst gradually became reduced without any treatment, and a reduction in diameter from 77 mm to 10 mm was observed after 8 years of follow-up. Spontaneous regression of congenital cysts of the liver in an adult seems to be very rare, and its mechanism is discussed.


Digestive Diseases and Sciences | 1997

Prediction of Effect of Interferon on Chronic Hepatitis C

Toshihiko Yamada; Yoshiaki Hashimoto; Shuichi Saitoh; Keiichirou Yuasa; Mariko Moriguchi; Tetsurou Sekiguchi; Hitoshi Takagi; Ken Takehara; Ryuya Shimoda; Satoru Kakizaki; Hisashi Takayama; Takehiko Abe; Tastuhiko Matsumoto; Akira Kojima; Jirou Takezawa; Takeaki Nagamine; Masatomo Mori

Clinical, pathological, and virological analysisincluding hypervariable region-1 of hepatitis C virus(HCV) was performed to predict the effect of interferon(IFN) on 41 patients with chronic hepatitis type C. The low virus load, low frequency ofthe mutation in the hypervariable region-1 as the changeof amino acid and high level of serum aminotransferasemake one estimate the good effect of IFN on patients with HCV. Mutation in the hypervariableregion-1 of HCV measured by fast assay fluorescencesingle-stranded conformational polymorphism was morefrequent in nonresponders to IFN than responders. Themost frequently mutated position was amino acidnumber 406. This indicates that the specific mutationsite might affect the response of IFN.


Cancer Chemotherapy and Pharmacology | 1994

Evaluation of the therapeutic effect of TAE on primary liver cancer

Toshihiko Yamada; Fujio Makita; Ken Takehara; Shuichi Saitou; Ken Satou; Keiichi Endou; Ryuya Shimoda; Yutaka Matsuzaki; Tatsuhiko Matsumoto; Keiichirou Yuasa; Hitoshi Takagi; Shoji Yamada; Masatomo Mori

The therapeutic effect of transcatheter arterial chemoembolization (TAE) performed on 31 patients with primary liver cancer was evaluated using the following procedures: (1) the alpha-fetoprotein (AFP) reduction rates and prognoses were analyzed according to the tumor reduction rates (TR), and (2) the AFP reduction rates and prognoses were also analyzed according to the tumor necrosis rates (TN) estimated by regarding every region with Lipiodol retention as being necrotic. The following results were obtained. The AFP level was 400 ng/ml or higher in 15 patients (48%). Their AFP reduction rates were as favorably high as 65.4%–99.8% (mean, 88.1%), and the AFP level was normalized in 3 patients. The cumulative survival rates after the initial treatment were relatively high, i.e., 78.4% in the 1 st year, 58.1% in the 2nd year, and 38.7% in the 3rd year. These results suggested the effectiveness of the TAE treatment undertaken in this study. Regarding the TR, the tumor was reduced in size by 50% or more in only 5 patients (16%), and most patients had a TR of less than 25%. On the other hand, the majority, 25 patients (81%), had a TN ranging between 50% and less than 100%, including 7 who had a TN ranging between 50% and less than 90% and 18 who had a TN ranging between 90% and less than 100%. There was no significant correlation between the AFP reduction rate and the TN or TR. Regarding evaluation of the cumulative survival rates by TR and TN, the 1-year survival rate was lower in patients having a TR of less than 25% than in those having a TR of 25% or more. Patients having a TN of less than 50% showed a poor outcome as compared with those having a TN of 50% or more. Although the TR was found to be less than 50% in a majority of the patients when the therapeutic effect of TAE on the liver cancer was evaluated according to the TR, many of these patients showed a good outocome. Thus, the conventional efficacy evaluation, in which a tumor reduction of 50% or more is considered to be effective, should be reconsidered. On the other hand, the TN was found to be 50% or more in most of the patients suggesting the necessity of a more detailed classification of TN. In relation to the survival rate patients having a TN of less than 50% showed a poor outcome.


Journal of Gastroenterology and Hepatology | 2011

Respiratory effects of balloon occluded retrograde transvenous obliteration of gastric varices: a prospective controlled study.

Hirotaka Arai; Takehiko Abe; Hisashi Takayama; Mitsuo Toyoda; Kazuyo Mori; Takashi Ueno; Hitoshi Takagi; Ryuya Shimoda

Background and Aim:  We evaluated the respiratory effects of balloon‐occluded retrograde transvenous obliteration (BRTO) performed for the treatment of gastric varices complicating liver cirrhosis.


Journal of Gastroenterology | 2002

Severe manifestation of acute hepatitis A recently found in Gunma, Japan.

Daisuke Kanda; Hitoshi Takagi; Yoshiaki Hashimoto; Yuichi Yamazaki; Masayuki Matsui; Takashi Kosone; Hirotaka Arai; Takeshi Ichikawa; Hiroaki Nakajima; Toshiyuki Otsuka; Akira Kojima; Ken Sato; Satoru Kakizaki; Yutaka Matsuzaki; Tatsuhiko Matsumoto; Ryuya Shimoda; Mieko Kaneko; Hisashi Takayama; Hitomi Takahashi; Takehiko Abe; Jiro Takezawa; Masatomo Mori

Background:Background: The incidence of acute hepatitis A infection in Japan peaked 10 years ago and has been decreasing since then. However, an increase in severe cases of the disease has been documented recently. We experienced an outbreak in 1998–1999, and compared the clinical features of the disease in 1998–1999 (recent outbreak) and in 1987–1988 (past outbreak) in our prefecture (Gunma). Methods: Forty patients with acute hepatitis A were admitted to nine Gunma hospitals from October 1998 to September 1999. Their clinical features were compared with those of 100 patients with acute hepatitis A admitted to the same hospitals in 1987–1988. Results: Both outbreaks occurred mostly during the winter-spring season. Secondary familial infection was significantly decreased in the recent outbreak. Patients in the recent outbreak were 7 years older than those in the past outbreak. Laboratory findings, such as serum aspartatate aminotransferase (AST) and alanine aminotransferase (ALT) levels and prothrombin time, were worse in the recent than in the past outbreak. Severe-type hepatitis and fulminant hepatitis occurred in 5 patients (12.5%) in the recent outbreak but in only 2 patients (2.0%) in the past outbreak. Conclusions: Clinical data and manifestations were more severe in the recent outbreak than in the past outbreak of acute hepatitis A. It is important to be aware of hepatitis A virus infection and to take into account the available vaccination against hepatitis A virus in Japan.


International Hepatology Communications | 1997

A new point mutation in cholinesterase: relationship between multiple mutation sites and enzyme activity

Hitoshi Takagi; Ayako Narahara; Hisashi Takayama; Ryuya Shimoda; Takeaki Nagamine; Masatomo Mori

Abstract A new mutation site has been found in a case of cholinesterase (ChE) deficiency diagnosed upon routine blood screening. Genomic DNA was sequenced and four point mutations were found: P1 (exon 2) nucleotide 298 (CCA-TCA), codon 100 (proline-serine), which is a novel mutation site; P4 (exon 2) nucleotide 1410 (CGT-CGG), codon 470 (arginine not changed); PS (exon 3) nucleotide 1543 (CGT-TGT), codon 515 (arginine-threonine); and P6 (exon 4) nucleotide 1615 (GCA-ACA), codon 539 (alanine-threonine). The patient had three (P1, P5, P6) heterozygous and one (P4) homozygous mutations. The three other family members studied had one (P1) or two (P5 and 6) heterozygous mutations in addition to a P4 homozygous mutation but their serum levels of ChE were normal or only slightly decreased. We concluded that three simultaneous mutations at codons 298, 1543 and 1615 are required to reduce serum ChE activity and that the single mutation at codon 298 or two mutations at codon 1543 and 1615 are not enough to reduce ChE activity.

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Hisashi Takayama

National Institutes of Health

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