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Dive into the research topics where Takeshi Suda is active.

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Featured researches published by Takeshi Suda.


Cancer | 1998

The usefulness of determining des‐γ‐carboxy prothrombin by sensitive enzyme immunoassay in the early diagnosis of patients with hepatocellular carcinoma

Yuhsaku Mita; Yutaka Aoyagi; Masahiko Yanagi; Takeshi Suda; Yasufumi Suzuki; Hitoshi Asakura

Measurements of serum concentrations of des‐γ‐carboxy prothrombin (DCP) are widely used for diagnosing hepatocellular carcinoma (HCC). However, the DCP is not always sensitive enough to detect small HCCs. In the current study, the authors investigated the usefulness of DCP in the early diagnosis of HCC, using a more sensitive enzyme immunoassay than is conventionally employed.


Pharmaceutical medicine | 2011

Advances in Gene Delivery Systems

Kenya Kamimura; Takeshi Suda; Guisheng Zhang; Dexi Liu

The transfer of genes into cells, both in vitro and in vivo, is critical for studying gene function and conducting gene therapy. Methods that utilize viral and nonviral vectors, as well as physical approaches, have been explored. Viral vector-mediated gene transfer employs replication-deficient viruses such as retrovirus, adenovirus, adeno-associated virus and herpes simplex virus. A major advantage of viral vectors is their high gene delivery efficiency. The nonviral vectors developed so far include cationic liposomes, cationic polymers, synthetic peptides and naturally occurring compounds. These nonviral vectors appear to be highly effective in gene delivery to cultured cells in vitro but are significantly less effective in vivo. Physical methods utilize mechanical pressure, electric shock or hydrodynamic force to transiently permeate the cell membrane to transfer DNA into target cells. They are simpler than viral- and nonviral-based systems and highly effective for localized gene delivery. The past decade has seen significant efforts to establish the most desirable method for safe, effective and target-specific gene delivery, and good progress has been made. The objectives of this review are to (i) explain the rationale for the design of viral, nonviral and physical methods for gene delivery; (ii) provide a summary on recent advances in gene transfer technology; (iii) discuss advantages and disadvantages of each of the most commonly used gene delivery methods; and (iv) provide future perspectives.


Cancer | 1998

The fucosylation index of α-fetoprotein as a possible prognostic indicator for patients with hepatocellular carcinoma

Yutaka Aoyagi; Osamu Isokawa; Takeshi Suda; Masashi Watanabe; Yasufumi Suzuki; Hitoshi Asakura

The aim of this study was to elucidate the usefulness of measuring the fucosylation index (FI) of α‐fetoprotein (AFP) before the initiation of therapy as a new prognostic indicator for patients with hepatocellular carcinoma (HCC).


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.


Journal of Gastroenterology and Hepatology | 2001

N‐Acetylglucosaminyltransferase V as a possible aid for the evaluation of tumor invasiveness in patients with hepatocellular carcinoma

Masahiko Yanagi; Yutaka Aoyagi; Takeshi Suda; Yuhsaku Mita; Hitoshi Asakura

A close relationship has been shown to exist between the metastatic potential and β1–6 branched oligosaccharides in human and rodent cells. N‐acetylglucosaminyltransferase V (GnT‐V) catalyzes this process. Although this phenomenon has been reported, little is known about the clinical usefulness of the determination of GnT‐V in the evaluations of tumor invasiveness in hepatocellular carcinoma (HCC). In this study, we measured the GnT‐V activity in serum of patients with HCC, together with its activity and gene expression in HCC tissues, and elucidated the clinical usefulness of the GnT‐V level in evaluating tumor invasiveness.


Journal of Hepatology | 2000

Plasma fucosyltransferase activity in patients with hepatocellular carcinoma, with special reference to correlation with fucosylated species of alpha-fetoprotein

Yuhsaku Mita; Yutaka Aoyagi; Takeshi Suda; Hitoshi Asakura

BACKGROUND/AIMS Our previous results showed that the percentage of fucosylated species of alpha-fetoprotein (AFP) in total AFP, fucosylation index, was a very useful diagnostic tool to distinguish AFP due to hepatocellular carcinoma from AFP due to non-neoplastic liver diseases. On the other hand, alpha1-6 fucosyl-transferase (alphaFT) catalyzes the addition of fucose from GDP-fucose through an alpha1-6 linkage to the reducing end of N-acetylglucosamine residue of N-linked oligosaccharides of glycoproteins. However, the biological and clinical significance of alphaFT in patients with hepatocellular carcinoma is not fully understood. In the present study, we measured alphaFT activity to elucidate the enzymatic background of fucosylated species of AFP in hepatocellular carcinoma. METHODS Plasma samples from 84 cases of hepatocellular carcinoma, 40 of liver cirrhosis, 40 of chronic hepatitis and 30 of normal controls, and 26 paired samples of hepatocellular carcinoma and surrounding noncancerous tissues were enrolled in the present study. AlphaFT activity was measured by high performance liquid chromatography with a synthesized fluorescence-labeled glycopeptide with an asialoagalactobiantennary sugar chain as a substrate in the presence of GDP-fucose. RESULTS Plasma alphaFT activities (mean+/-SD, pmol/ml/h) in patients with hepatocellular carcinoma, liver cirrhosis, chronic hepatitis and normal controls were 435+/-271, 490+/-290, 590+/-209 and 380+/-133, respectively. AlphaFT levels in hepatocellular carcinoma and chronic liver diseases were increased compared with that in normal controls. A statistically significant positive correlation was observed between plasma alphaFT activity and fucosylation index of AFP (r=0.34, p= 0.0032) in 60 patients with hepatocellular carcinoma, in which increments of serum AFP were observed. When the tentative cutoff value of fucosylation index was set at 18%, which corresponded to the cutoff value to discriminate between hepatocellular carcinoma and non-neoplastic liver diseases in our previous study, the plasma alphaFT activity in hepatocellular carcinoma patients whose fucosylation index was more than 18% (n=32, 523+/-324 pmol/ml/h) was higher than that in hepatocellular carcinoma patients whose fucosylation index was equal to or less than 18% (n=28, 383+/-229) (p=0.055). An increment of the plasma levels of alphaFT occurred in accordance with an advancement of hepatocellular carcinoma stages. Tissue aFT activity in hepatocellular carcinoma (175+/-178 pmol/mg/h) was higher than those in surrounding noncancerous liver (144+/-134) and in normal liver (79+/-19). The mean alphaFT activities in well-, moderately- and poorly-differentiated hepatocellular carcinoma were 38+/-0.7, 177+/-182 and 219+/-189, respectively, and they tended to increase with dedifferentiation in hepatocellular carcinoma tissues. CONCLUSIONS The present study indicates that alphaFT is responsible for the formation of the fucosylated species of AFP in hepatocellular carcinoma and suggests that the measurement of alphaFT provides a possible aid in the evaluation of the degree of advancement in patients with hepatocellular carcinoma.


Digestive Diseases | 2013

Hypovascular Hepatic Nodules Showing Hypointense on the Hepatobiliary-Phase Image of Gd-EOB-DTPA-Enhanced MRI to Develop a Hypervascular Hepatocellular Carcinoma: A Nationwide Retrospective Study on Their Natural Course and Risk Factors

Tatsuo Inoue; Tomoko Hyodo; Takamichi Murakami; Yukihisa Takayama; Akihiro Nishie; Atsushi Higaki; Keiko Korenaga; Azusa Sakamoto; Yukio Osaki; Kazuaki Chayama; Takeshi Suda; Toru Takano; Kennichi Miyoshi; Masahiko Koda; Kazushi Numata; Hironori Tanaka; Hiroko Iijima; Hironori Ochi; Masashi Hirooka; Yasuharu Imai; Masatoshi Kudo

Objective: We aimed to investigate the natural outcome of nonhypervascular lesions detected in the hepatobiliary phase of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MRI by performing a longitudinal study retrospectively enrolled in a nationwide manner. Methods: Between February 2008 and March 2011, 224 patients with 504 nodules that were diagnosed as nonhypervascular by imaging were recruited from institutions that participated in the present study. We examined the natural outcome of nonhypervascular lesions and evaluated the risk factors. Results: Of the 504 nodules, 173 (34.3%) showed hypervascular transformation. The overall cumulative incidence of hypervascular transformation was 14.9% at 12 months and 45.8% at 24 months. Multivariate analysis using the Cox regression model revealed previous treatment history for hepatocellular carcinoma (HCC; relative risk = 1.498; p = 0.036, 95% CI 1.03-2.19) and hyperintensity on T2-weighted images (relative risk = 1.724; p = 0.015, 95% CI 1.11-2.67) were identified as independent factors for hypervascular transformation. Conclusions: Patients who have a previous treatment history for HCC and with hypointense nodules showing hyperintensity on T2-weighted images need careful follow-up because of the high incidence of hypervascular transformation.


Molecular therapy. Nucleic acids | 2013

Parameters Affecting Image-guided, Hydrodynamic Gene Delivery to Swine Liver

Kenya Kamimura; Takeshi Suda; Guisheng Zhang; Yutaka Aoyagi; Dexi Liu

Development of a safe and effective method for gene delivery to hepatocytes is a critical step toward gene therapy for liver diseases. Here, we assessed the parameters for gene delivery to the livers of large animals (pigs, 40–65 kg) using an image-guided hydrodynamics-based procedure that involves image-guided catheter insertion into the lobular hepatic vein and hydrodynamic injection of reporter plasmids using a computer-controlled injector. We demonstrated that injection parameters (relative position of the catheter in the hepatic vasculature, intravascular pressure upon injection, and injection volume) are directly related to the safety and efficiency of the procedure. By optimizing these parameters, we explored for the first time, the advantage of the procedure for sequential injections to multiple lobes in human-sized pigs. The optimized procedure resulted in sustained expression of the human α-1 antitrypsin gene in livers for more than 2 months after gene delivery. In addition, repeated hydrodynamic gene delivery was safely conducted and no adverse events were seen in the entire period of the study. Our results support the clinical applicability of the image-guided hydrodynamic gene delivery method for the treatment of liver diseases.


PLOS ONE | 2014

Safety Assessment of Liver-Targeted Hydrodynamic Gene Delivery in Dogs

Kenya Kamimura; Tsutomu Kanefuji; Takeshi Yokoo; Hiroyuki Abe; Takeshi Suda; Yuji Kobayashi; Guisheng Zhang; Yutaka Aoyagi; Dexi Liu

Evidence in support of safety of a gene delivery procedure is essential toward gene therapy. Previous studies using the hydrodynamics-based procedure primarily focus on gene delivery efficiency or gene function analysis in mice. The current study focuses on an assessment of the safety of computer-controlled and liver-targeted hydrodynamic gene delivery in dogs as the first step toward hydrodynamic gene therapy in clinic. We demonstrate that the impacts of the hydrodynamic procedure were limited in the injected region and the influences were transient. Histological examination and the hepatic microcirculation measurement using reflectance spectrophotometry reveal that the liver-specific impact of the procedure involves a transient expansion of the liver sinusoids. No systemic damage or toxicity was observed. Physiological parameters, including electrocardiogram, heart rate, blood pressure, oxygen saturation, and body temperature, remained in normal ranges during and after hydrodynamic injection. Body weight was also examined to assess the long-term effects of the procedure in animals who underwent 3 hydrodynamic injections in 6 weeks with 2-week time interval in between. Serum biochemistry analysis showed a transient increase in liver enzymes and a few cytokines upon injection. These results demonstrate that image-guided, liver-specific hydrodynamic gene delivery is safe.


Archive | 2002

CASE REPORT: Bile Duct Involvement in a Case of Autoimmune Pancreatitis Successfully Treated with an Oral Steroid

Takashi Kuroiwa; Takeshi Suda; Toru Takahashi; Haruka Hirono; Masaaki Natsui; Hirotaka Motoyama; Minoru Nomoto; Yutaka Aoyagi

In the case reported here, the characteristic features of AIP were evaluated by ultrasonography, computed tomography and endoscopic retrograde cholangiopancreatography, initially in the intrahepatic- and extrahepatic bile ducts, and later in the pancreas. In addition, histological examination revealed lymphocytic sclerosis around the intralobular bile ducts, as is reported in AIP, without chronic nonsuppurative destructive cholangitis or onion-skin-like appearance. Immunohistochemistry identified the infiltrating lymphocytes as T cells. Although hypergammaglobulinemia was observed with elevation of hepatobiliary and pancreatic enzymes, no other serological or physiological abnormalities suggestive of other systemic autoimmune diseases were detected. These findings progressed over a three-month period and were dramatically resolved within one month by steroid therapy. These observations support a novel clinical entity characterized by the presence of bile duct lesions similar to the pancreatic involvement seen in AIP that is distinct pathophysiologically, histologically, and therapeutically from the so-called autoimmune cholangitis or primary sclerosing cholangitis.

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Kenya Kamimura

University of Pittsburgh

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