N Tsukada

Keiyu Hospital, Yokohama, Kanagawa, Japan

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Publications (71)184.26 Total impact

  • Nihon Naika Gakkai Zasshi 03/2014; 103(3):741-3.
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    ABSTRACT: We conducted a retrospective study of the efficacy of a polyethylene glycol purge before colonoscopic examination in 110 patients with colonic diverticular bleeding. The patients' data were assessed for the timing of colonoscopy and the methods used to stop bleeding. The rate at which bleeding diverticula were identified was markedly higher when a purge was used than when it was not (28.2% vs. 12.0%, p=0.11). In addition, the identification rate was significantly higher when colonoscopic examination was performed within 18 hours of the final hematochezia than when it was performed after 18 hours (40.5% vs. 10.5%, p<0.01). These findings suggest that patients with diverticular bleeding should undergo colonoscopy following an orally administered colonic purge, providing their condition permits. Furthermore, colonoscopy should be performed within 18 hours of the final hematochezia in order to improve identification of the bleeding diverticulum.
    Nippon Shokakibyo Gakkai zasshi The Japanese journal of gastro-enterology 11/2013; 110(11):1927-33.
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    ABSTRACT: A 42-year-old man was admitted to our hospital with a lower extremity rash, general fatigue, and abdominal discomfort. Laboratory findings revealed elevated serum transaminases as well as positivity for the hepatitis B surface antigen and the immunoglobulin M type anti-hepatitis B core antibody. He was diagnosed with a rash typical of Gianotti-Crosti syndrome due to acute infection with hepatitis B virus, genotype A. After admission, the rash gradually decreased; however, serum transaminases and jaundice increased. Entecavir therapy was initiated on day 11 of admission, and his liver function subsequently improved over two weeks. Gianotti-Crosti syndrome is rarely seen in adult patients. It may be important to pay attention to the typical rash of Gianotti-Crosti syndrome because it may provide an important clue to an otherwise asymptomatic acute hepatitis B infection.
    Nippon Shokakibyo Gakkai zasshi The Japanese journal of gastro-enterology 09/2013; 110(9):1657-62.
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    ABSTRACT: A flexible spectral imaging color enhancement system was installed in new capsule software for video capsule endoscopy. Contrast image capsule endoscopy (CICE) is a novel technology using light-emitting diodes selected for the main absorption range of hemoglobin. We assessed the feasibility and diagnostic effi cacy for small bowel surveillance in patients with polyposis syndromes. Six patients with polyposis syndromes, four with familial adenomatous polyposis and one each with Cowden syndrome (CS) and Cronkhite-Canada syndrome (CCS) were examined using CICE. We conducted three evaluations to assess the effect on the numbers of the detected polyps; compare polyp diagnostic rates between adenoma and hamartoma; and assess polyp visibility. The numbers of detected polyps and diagnostic accuracy did not differ signifi cantly between pre-contrast and contrast images. However, 50% of the adenomatous polyps displayed enhanced visibility on contrast images. CICE contrast images exhibited clearly demarcated lesions and improved the visibility of minute structures of adenomatous polyps. Hamartomatous polyp micro-structures in patients with CS and CCS were more clearly visualized on contrast than pre-contrast images. CICE is an effective tool for enhancing the visibility of polyps in patients with polyposis syndrome.
    Gut and liver 04/2012; 6(2):218-22. · 1.31 Impact Factor
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    ABSTRACT: A 41-year-old man was admitted to our hospital with gastrointestinal bleeding. Esophagogastroduodenoscopy revealed a submucosal protrusion with erosion in the duodenal bulb which was thought to be the bleeding source. Dynamic CT scan, ultrasonography and angiography of the abdomen revealed a hepatic artery aneurysm and a dilated celiac artery that dissected from its origin. Although we considered percutaneous transcatheter arterial embolization with metallic coils, we chose surgical resection and vascular reconstruction to prevent hepatic ischemia resulting from interruption of collateral circulation. On the 8(th) day, hepatic artery aneurysmectomy and revascularization with a great saphenous vein was carried out without any severe complication. The pathological specimen demonstrated segmental arterial mediolysis.
    Nippon Shokakibyo Gakkai zasshi The Japanese journal of gastro-enterology 01/2012; 109(2):247-54.
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    ABSTRACT: PURPOSE: Peginterferon (PEG-IFN) and ribavirin (RBV) combination treatment for patients with chronic hepatitis C (CHC), infected by genotype-1 hepatitis C virus with high viral loads, results in a sustained viral response (SVR) in ~50%. However, a trend of decreasing SVR in the older patients has been reported. In the present study, we verified this trend of treatment efficacy in older patients using the propensity score (PS). METHODS: We conducted a survey of 327 patients with CHC (genotype 1 and high viral loads) who were treated with PEG-IFN and RBV for 48 weeks. The SVR rate was compared between patients =60 and <60 years of age. Because backgrounds of these patients differed considerably, we verified this efficacy between the older (n = 102) and younger (n = 102) patients matched for gender, body weight, platelets (PLT), and red blood cell (RBC) counts using PS. RESULTS: The total SVR rate was 42.9% (161/327); this rate decreased with increasing age and was lower in the older patients (≥60 years: 41.5%, <60 years: 54.3%, P = 0.0245). Moreover, younger age was a significant factor for SVR. After correction by PS, the SVR in older patients remained significantly lower (≥60 years: 43.1%, <60 years: 57.8%, P = 0.0497). In addition, RBC counts and hemoglobin (Hgb) concentrations, as well as RBV adherence in the older patients, decreased with this treatment, although there were no significant differences in pretreatment RBC and Hgb levels. CONCLUSIONS: The analysis using PS indicated that RBV adherence in the older patients decreased even if they did not have lower pretreatment RBC and Hgb levels.
    Hepatology International 09/2011; · 2.64 Impact Factor
  • Gastroenterology 01/2011; 140(5). · 12.82 Impact Factor
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    ABSTRACT: A 57-year-old man with advanced gallbladder cancer and accompanying hepatic, colonic and duodenal invasion and para-aortic lymph node metastasis was referred to our hospital. Gemcitabine plus S-1 administration was chosen. Gemcitabine was administered intravenously at a dose of 1000 mg/m(2) on days 1 and 15, and repeated every 4 weeks. S-1 was administered orally at a dose of 40 mg/m(2) b.i.d. on days 1-14. Chemotherapy was effective for the primary gallbladder tumor and lymph node metastasis. The primary tumor and metastatic lymph nodes were shown to have disappeared by a FDG-PET CT study after 10 courses of chemotherapy. Informed consent was obtained prior to performing surgery of the primary lesion. Pathological examination showed fibrosis and a small focus of residual cancer in the resected gallbladder. Complete resection was achieved as all the margins were negative. The findings suggest that gemcitabine plus S-1 treatment may be effective against advanced gallbladder cancer.
    Nippon Shokakibyo Gakkai zasshi The Japanese journal of gastro-enterology 01/2011; 108(7):1263-70.
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    ABSTRACT: To assess the efficacy of the additional treatment of transcatheter arterial chemoembolization (TACE) to percutaneous ethanol injection (PEI) therapy for relatively small hepatocellular carcinomas (HCCs), a multicenter randomized control study (RCT) was performed. We conducted an RCT and follow-up study during the enrollment period from 1997 to 1999. Newly diagnosed patients with one to three HCC tumors measuring from 2 to 4 cm (4 cm maximum) in diameter were enrolled. A total of 30 patients initially underwent a combination TACE-PEI or PEI-alone therapies at eight randomly assigned Japanese hospitals. However, 3 patients withdrew. Of the 27 remaining patients, 13 were treated with the combination TACE-PEI therapy and 14 with PEI therapy alone. The patients were observed over several months [median (interquartile range) 33.2 (24.6) months]. There were no significant differences in the background of the patients between the two groups. Among the patients treated with TACE-PEI, the development of a local residual tumor was of significantly lower occurence, compared to the group receiving PEI alone (7.6 and 42.9%, respectively; P=0.024). However, the mean cancer-free time (absence of local or multiple nodule recurrence) or patient survival time was not significantly different between the two groups [PEI alone vs. TACE-PEI: cancer-free time 16.7 (95% CI 7.3-26.0) vs. 22.9 months (95% CI 12.4-33.4); survival time 57.2 (95% CI 37.2-77.2) vs. 42.4 months (95% CI 29.2-55.6)]. Although the combination of TACE and PEI had significant effects on the local tumor control, no efficacy of the addition of TACE to PEI was noted in the prognosis among patients with relatively small HCC tumors.
    Oncology letters 09/2010; 1(5):855-859. · 0.24 Impact Factor
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    ABSTRACT: Polyneuropathy, organomegaly, endocrinopathy, M protein, and skin changes (POEMS) syndrome is a rare multi-system disease. Reported herein is an autopsy case of POEMS syndrome in a subject who developed idiopathic portal hypertension (IPH). The patient was a 38-year-old woman who was initially admitted to the Saiseikai Central Hospital because of polyneuropathy and edema. Diagnosis of POEMS syndrome was established on additional symptoms (splenomegaly and papilloedema) and serum M-protein. Corticosteroid was given for 10 years. The patient was admitted again at the age of 48 years because of gastrointestinal bleeding due to portal hypertension. The patient died of hepatoencephalopathy at 58 years of age. The liver at autopsy demonstrated dense portal fibrosis and obliteration of small portal vein branches, which are characteristic histological findings of IPH. Portal hypertension is a rare symptom in POEMS syndrome. Only three cases of IPH associated with POEMS syndrome (including the present one) have been reported so far. In the previous two reports, liver biopsy failed to determine the cause of portal hypertension. This is the first report on the occurrence of histological findings compatible with IPH in the liver. Although it is not confirmed whether IPH is related to POEMS syndrome, elevated serum cytokines such as vascular endothelial growth factor and coagulation abnormality could have contributed to the development of IPH in the present case.
    Pathology International 04/2010; 60(4):316-20. · 1.72 Impact Factor
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    ABSTRACT: We investigated the relationship between serum ribavirin concentrations and clearance, as well as therapeutic efficacy and adverse reactions, in 97 Japanese patients with chronic hepatitis C virus infections treated with a 6-month course of high-dose alpha2b interferon (6 million units/day) plus ribavirin (600 to 800 mg/day) combination therapy. This randomized trial showed that the saturation of ribavirin uptake after taking ribavirin capsules does not occur within a dose range of 600 to 800 mg/day, which is a standard dosage used clinically in Japan. Serum ribavirin concentrations and clearance did not correlate with sustained virological response rates. Fourteen patients discontinued therapy because of adverse reactions, and sustained virological response rates were significantly reduced by discontinuation of therapy, while dose reduction of ribavirin did not alter the therapeutic effects. Ribavirin concentrations after 1 week and ribavirin clearance were significantly correlated with discontinuation of ribavirin; however, a multiple-regression analysis revealed that only hemoglobin concentration, but not ribavirin clearance, was a significant factor for discontinuation of therapy (odds ratio, 0.514; 95% confidence interval, 0.311 to 0.85; P = 0.0095). It appears that peripheral erythrocytes may act as a reservoir for ribavirin and regulate serum ribavirin levels in the very early phase of treatment.
    Journal of Clinical Microbiology 11/2006; 44(10):3562-8. · 4.07 Impact Factor
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    ABSTRACT: We devised and evaluated a clinical pathway (CP) protocol for patients with bleeding peptic ulcers (BPU). Patients without severe comorbidities, who had been diagnosed with BPU and who had undergone endoscopic treatment, were enrolled in our study. The CP adaptation rate for BPU patients was 78.8% (89/113). The variance rate was 13.5% (12/89). The median length of admission was 10.0 +/- 4.6 days (n = 78) before and 7.4 +/- 2.9 days (n = 77) after introducing CP. Our CP for BPU was safe and resulted in shorter hospital stays and, therefore, cost reductions. In elder patients, our CP was also successful, but the variance rate was higher than in younger patients.
    Nippon Shokakibyo Gakkai zasshi The Japanese journal of gastro-enterology 04/2006; 103(3):283-9.
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    ABSTRACT: There are no management criteria for optimum out-patient care in mild-to-moderate acute colonic diverticulitis. To enable such patients to be managed in an out-patient setting, by establishing criteria and treatment protocols. We conducted an open trial and follow-up study from 1997 to 2002. On the basis of ultrasonography, we defined and categorized mild-to-moderate acute colonic diverticulitis ranging from limited inflammation within diverticulum to an abscess < 2 cm in diameter. Subjects were treated as out-patients and followed a 10-day treatment protocol consisting of an oral antibiotic and a sports drink for the first 3 days. Physical examination and laboratory testing helped determine whether or not a patient could resume a liquid diet on day 4, and a regular diet on day 7. Of the 70 patients, 68 were successfully treated. Two patients required hospitalization. Of the 65 patients who were tracked over several months [median (intraquarter range) = 30.8 (11.9-44.2) months], 16 had one or more clinical recurrences. The medical cost per episode was 80% lower than in-patient treatment. Patients with mild-to-moderate acute colonic diverticulitis can be safely and successfully treated as out-patients using this protocol.
    Alimentary Pharmacology & Therapeutics 04/2005; 21(7):889-97. · 4.55 Impact Factor
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    ABSTRACT: Basic fibroblast growth factor (bFGF) is a key factor in the healing of human and experimental peptic ulcers, but the behavior of bFGF in human giant gastric ulcer remains to be determined. We determined the bFGF content in the rim of giant ulcers (bFGF rim) and in non-ulcerated mucosa located opposite the ulcer (bFGF opposite) before and during treatment. Biopsy specimens were endoscopically obtained from 31 patients with giant gastric ulcers and 17 patients with small ulcers before and 2, 4 and 8 weeks after treatment. The bFGF concentrations in the specimens were measured using a sandwich enzyme immunoassay. Before treatment, the bFGF rim and bFGF opposite concentrations were not associated with ulcer size. The bFGF rim concentration before treatment in the rapid healing group was higher than that in the slow healing group, but no significant difference in bFGF opposite concentrations were found between the two groups. The bFGF rim concentration in the rapid healing patients decreased during treatment, while the slow healing patients showed an inverse response. The bFGF opposite concentration did not change during treatment and bFGF rim concentrations in Helicobacter pylori-positive stomachs were significantly lower than those in H. pylori-negative stomachs. The bFGF rim concentration is not involved in the formation of giant gastric ulcers in humans. However, the bFGF rim concentration does appear to promote healing. The bFGF opposite concentration is not related to either the formation or healing of giant gastric ulcers.
    Journal of Gastroenterology and Hepatology 06/2004; 19(5):528-34. · 3.33 Impact Factor
  • Gastroenterology 04/2003; 124(4). · 12.82 Impact Factor
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    ABSTRACT: Intracytoplasmic free calcium ions (Ca++) are maintained at a very low concentration in mammalian tissue by extruding Ca++ from the cytoplasm against a steep extracellular Ca++ concentration gradient, mainly through the activity of plasma membrane Ca++ pump-ATPase. The present study aimed to elucidate how endothelin-1 (ET-1) affects the morphology of sinusoidal endothelial fenestrae and ultrastructural distribution of plasma membrane ATPases and intracytoplasmic free Ca++ in isolated rat hepatic sinusoidal endothelial cells. Sinusoidal endothelial fenestrae were observed by scanning electron microscope. Ando's electron cytochemical method was used for ultrastructural localization of Ca++-Mg++-ATPase activity, electron immunogold postembedding method for Ca++ pump-ATPase immunoactivity, and antimonate method for intracytoplasmic free Ca++. Addition of ET-1 to sinusoidal endothelial cells significantly decreased Ca++-Mg++-ATPase activity and Ca++ pump-ATPase expression and increased intracytoplasmic free Ca++ concentration, concomitant with a decrease in diameter of sinusoidal endothelial fenestrae. Co-treatment with Bosentan abolished the actions of ET-1. These results suggest that ET-1 suppresses Ca++-Mg++-ATPase activity and Ca++ pump-ATPase expression on the plasma membrane of sinusoidal endothelial fenestrae, thereby attenuating the extrusion of intracytoplasmic free Ca++ into the extracellular space, leading to an increased concentration of intracytoplasmic free calcium ions and contraction of sinusoidal endothelial fenestrae.
    American Journal Of Pathology 03/2003; 162(2):557-66. · 4.60 Impact Factor
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    Hepatology Research 05/2002; 22(4):323-324. · 2.07 Impact Factor
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    ABSTRACT: A 55-year-old man was admitted to our hospital with fever and vomiting. Abdominal computed tomography (CT) revealed multiple low density masses in the liver. A diagnosis of primary adenosquamous carcinoma of the liver was confirmed by histological examination of a necropsy specimen. The present case showed leukocytosis and hypercalcemia with high levels of serum granulocyte-colony-stimulating factor (G-CSF) and parathyroid hormone related protein (PTHrP). Recent studies have shown that G-CSF and PTHrP are responsible for the paraneoplastic syndromes with leukocytosis and hypercalcemia. The tumor cells demonstrated positive cytoplasmic immunohistochemistry staining with anti-G-CSF and anti-PTHrP antibodies. This result suggested that the tumor produced G-CSF and PTHrP.
    Internal Medicine 08/2001; 40(7):631-4. · 0.97 Impact Factor
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    ABSTRACT: Nitric oxide is synthesized in diverse mammalian tissues by a family of calmodulin-dependent nitric oxide synthases (NOS). Caveolin, the principal structural protein in caveolae, interacts with endothelial NOS leading to enzyme inhibition in a reversible process modulated by Ca++-calmodulin. The aim of the present study was to clarify the ultrastructural localization of eNOS and caveolin-1 in hepatic sinusoidal endothelium by an electron immunogold method. Male Wistar rats were used. Liver tissues and hepatic sinusoidal endothelial cells isolated from rat livers by collagenase infusion were studied. For immunohistochemistry, liver specimens were reacted with anti-eNOS or anti-caveolin-1 antibody. The ultrastructural localization of eNOS or caveolin-1 was identified by electron microscopy using an immunogold post-embedding method. Immunohistochemical studies using liver tissues localized endothelial NOS in hepatic sinusoidal lining cells, portal veins and hepatic arteries; and caveolin-1 in sinusoidal lining cells, bile canaliculi, portal vein and hepatic arteries. Immunogold particles indicating the presence of eNOS and caveolin-1 were demonstrated on the plasma membrane of sinusoidal endothelial fenestrae in liver tissue and also in isolated sinusoidal endothelial cells. Endothelial NOS and caveolin are co-localized on sinusoidal endothelial fenestrae, suggesting that interaction of the two may modulate cellular regulation of NO synthesis.
    Liver International 07/2001; 21(3):198-206.
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    ABSTRACT: To investigate the effects of T-helper cytokines on Kupffer cells (KCs), the effects of interferon-gamma (IFN-gamma; Th1 cytokine) and interleukin-4 (IL-4; Th2 cytokine) on KC morphology and their role in modulating the growth of hepatic stellate cells (HSCs) were examined. Fluorescence microscopic and electron microscopic data demonstrated that IL-4 transforms rat KCs into multinucleated giant cells (MGCs) in vitro. This transformation was inhibited by the addition of anti-ICAM-1 and anti-CD18 monoclonal antibodies. In addition, IL-4-induced KC transformation was suppressed by the presence of IFN-gamma. The formation of mouse hepatic MGCs was also demonstrated in vivo by the intraperitoneal injection of recombinant mouse IL-4. Although the presence of MGCs was found in all five out of five livers from IL-4-treated Th2-dominant BALB/c mice, but it was in only two out of five livers from IL-4-treated Th1-dominant C57BL/6 mice. In addition, fewer MGCs were found in the liver of C57BL/6 mice. In contrast, IFN-gamma treatment did not form hepatic MGCs in mice at all. The growth of HSCs in vitro was significantly increased by the addition of culture supernatant from lipopolysaccharide-stimulated rat KCs. Pretreatment of the KCs with either IFN-gamma or IL-4 further enhanced the growth stimulation. These results suggest that IFN-gamma and IL-4 affect KC morphology differently, but that both Th1 and Th2 cytokines play a similar role in the modulation of HSC growth by Kupffer cells in the presence of lipopolysaccharide.
    Hepatology Research 07/2001; 20(2):193-206. · 2.07 Impact Factor

Publication Stats

396 Citations
184.26 Total Impact Points


  • 2013
    • Keiyu Hospital
      Yokohama, Kanagawa, Japan
  • 2002–2012
    • Tokyo Saiseikai Central Hospital
      Edo, Tōkyō, Japan
  • 1985–2011
    • Keio University
      • • Department of Internal Medicine
      • • School of Medicine
      Tokyo, Tokyo-to, Japan
  • 2010
    • North Internal Medicine
      Bartlett, Tennessee, United States
  • 2001–2002
    • Tokyo Metropolitan Hiroo Hospital
      • Division of Internal Medicine
      Tōkyō, Japan
    • Saitama Medical University
      • Department of Internal Medicine
      Saitama, Saitama-ken, Japan
  • 1991–1995
    • SickKids
      • Division of Pathology
      Toronto, Ontario, Canada
  • 1994
    • Nippon Medical School
      • Department of Internal Medicine
      Tokyo, Tokyo-to, Japan
  • 1993
    • University of Toronto
      • Hospital for Sick Children
      Toronto, Ontario, Canada