Koji Takahashi

Dr. Koji Takahashi

orcid

Research Focus & Metrics

Academic Career Length

24Years (2003-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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5 May 2017 in PLOS ONE
Verified
Journal Article
Open access
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MNMasato Nakamura
Masato Nakamura
Tatsuo KandaTatsuo Kanda
Tatsuo Kanda
ZZZengren Zhao
Zengren Zhao
YHYuki Haga
Yuki Haga
KTKoji Takahashi
Koji Takahashi
OYOsamu Yokosuka
Osamu Yokosuka
Noninvasive methods to accurately and conveniently evaluate liver fibrosis are desirable. MicroRNA (miR) is one of the candidates. MiRs are small RNAs consisting of 19–25 nucleotides that negatively regulate many target genes at transcriptional levels. Recently, many researchers have focused on circulating miRs in the blood stream as biomarkers. Hepatic miR-122 has been reported to have an association with viral replication and hepatic fibrosis in chronic hepatitis B virus (HBV) and hepatic C virus (HCV) infection. We measured serum miR-122 levels in HBV- and HCV-infected patients confirmed with liver biopsy. We also investigated a novel liver fibrosis marker Wisteria floribunda agglutinin-positive Mac-2 binding protein [WFA(+)-M2BP]. We evaluated the diagnostic usefulness of these markers in hepatic fibrosis and inflammation of patients with chronic viral infection. The serum miR-122 levels of HBV-infected patients were higher than those of the control subjects. In HBV-infected patients, the serum miR-122 levels of patients with advanced liver fibrosis were significantly lower. Serum WFA(+)-M2BP was significantly higher dependent on both the staging of fibrosis and the grading of inflammatory activity in patients with both HBV and HCV infection. We also observed that higher serum WFA(+)-M2BP levels augmented the prediction of advanced liver fibrosis among HBV-infected patients with lower serum miR-122 levels. A lower serum miR-122 level is a useful predictor of advanced liver fibrosis in HBV-infected patients. Serum WFA(+)-M2BP could predict liver fibrosis in both HBV and HCV infection. The combination of these markers may result in the more accurate evaluation of liver fibrosis in HBV infection.

20 December 2018 in PLOS ONE
Verified
Journal Article
Open access
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JKJunichiro Kumagai
Junichiro Kumagai
TTTakashi Taida
Takashi Taida
SOSadahisa Ogasawara
Sadahisa Ogasawara
TNTomoo Nakagawa
Tomoo Nakagawa
YIYotaro Iino
Yotaro Iino
NKNaoya Kato
Naoya Kato
In Western countries, most patients with primary sclerosing cholangitis (PSC) have concurrent ulcerative colitis (UC). The number of patients with UC in East Asia has increased markedly over the past two decades. However, current clinical features of PSC and of PSC associated with UC (PSC-UC) have not yet been clarified in East Asia, particularly in Japan. We aimed to reveal the clinical courses and associations with UC in Japanese patients with PSC from the mutual viewpoint of PSC and UC. We retrospectively retrieved medical records of patients with PSC (69) and UC (1242) who were diagnosed at Chiba University Hospital between June 1991 and August 2017. In the present cohort, 37 patients had PSC-UC; the cumulative risks of PSC in patients with UC and of UC in patients with PSC were 3.0% and 53.6%, respectively. We confirmed similar distinctive results by a Japanese nationwide survey, noting that younger patients with PSC had a notably high possibility of association with UC. From the viewpoint of the UC cohort, the occurrence of right-sided disease was significantly higher in patients with PSC-UC than in those with UC (16.2% vs. 4.2%, P = 0.003). Pancolitis was more commonly observed in PSC-UC, and proctits/left-sided colitis was less commonly found in patients with UC. The number of patients with young-onset PSC-UC may be increasing similar to an increase in patients with UC in Japan. In our cohort, the comorbidity rate of PSC-UC was higher than that obtained in previous reports. The incidence of PSC-UC and UC may increase in the future in East Asia, particularly in Japan.

Verified
Journal Article
Open access
PDF file
Tatsuo KandaTatsuo Kanda
Tatsuo Kanda
SYShin Yasui
Shin Yasui
MNMasato Nakamura
Masato Nakamura
ESEiichiro Suzuki
Eiichiro Suzuki
MAMakoto Arai
Makoto Arai
OYOSAMU YOKOSUKA
OSAMU YOKOSUKA
The aim of this study was to characterize the treatment response and serious adverse events of ledipasvir plus sofosbuvir therapies in Japanese patients infected with hepatitis C virus (HCV) genotype 1 (GT1). This retrospective study analyzed 240 Japanese HCV GT1 patients treated for 12 weeks with 90 mg of ledipasvir plus 400 mg of sofosbuvir daily. Sustained virological response at 12 weeks post-treatment (SVR12) was achieved in 236 of 240 (98.3%) patients. Among treatment-naïve patients, SVR12 was achieved in 136 of 138 (98.6%) patients, and among treatment-experienced patients, SVR12 was achieved in 100 of 102 (98.0%) patients. In patients previously treated with peginterferon plus ribavirin with various HCV NS3/4A inhibitors, 100% SVR rates (25/25) were achieved. Two relapsers had HCV NS5A resistance-associated variants (RAVs), but no HCV NS5B-S282 was observed after they relapsed. We experienced two patients with cardiac events during treatment. In conclusion, combination of ledipasvir plus sofosbuvir for 12 weeks is a potential therapy for HCV GT1 patients. Caution is needed for HCV NS5A RAVs, which were selected by HCV NS5A inhibitors and cardiac adverse events.

5 May 2017 in Cancers
Verified
Journal Article
Open access
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Tatsuo KandaTatsuo Kanda
Tatsuo Kanda
KTKoji Takahashi
Koji Takahashi
MNMasato Nakamura
Masato Nakamura
Shingo NakamotoShingo Nakamoto
Shingo Nakamoto
SWShuang Wu
Shuang Wu
OYOSAMU YOKOSUKA
OSAMU YOKOSUKA
Hepatocellular carcinoma (HCC) is a male-dominant disease with poor prognosis. Sorafenib is the only approved systemic chemotherapeutic drug for patients with advanced HCC. Previous studies have shown that androgen and androgen receptor (AR) are involved in human hepatocarcinogenesis and the development of HCC. Here, we discuss the recent data on AR and HCC, and the combination of sorafenib and inhibitors of AR for advanced-HCC patients. Androgen-dependent and androgen-independent AR activation exist in human hepatocarcinogenesis. AR could directly control hepatocarcinogenesis and regulate the innate immune system to influence HCC progression. Combination of sorafenib with AR inhibitors might represent a potential treatment for patients with advanced HCC.

1 August 2004 in Journal of Hand Surgery (European Volume)
Verified
Journal Article
Closed access
YAY. Abe
Y. Abe
TRT. Rokkaku
T. Rokkaku
SOS. Ofuchi
S. Ofuchi
STS. Tokunaga
S. Tokunaga
KTKoji Takahashi
Koji Takahashi
HMHidekazu Moriya
Hidekazu Moriya
We studied 135 hands in 77 Japanese patients to assess the frequency of radial involvement and its association with recurrence and the Dupuytren’s diathesis. The radial aspect of the hand was affected in 22% of the hands. Diseased cords were observed in ten patients who underwent surgery on the radial aspect of the hand. Longitudinal cords on the radial side of thenar eminence and distal transverse interdigital cords were common. The radial aspect of the hand was the most common site of disease extension, though recurrence never occurred after excision of a radial lesion. Ectopic lesions, bilateral hand involvement, and recurrence were significantly more frequent in patients with the radial side involvement. Thus the results of this study suggest that radial side disease is associated with the Dupuytren’s diathesis and is a risk factor of recurrence.

1 February 2024 in Internal Medicine
Verified
Journal Article
Open access
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TYTetsuhiko Yasuno
Tetsuhiko Yasuno
KTKoji Takahashi
Koji Takahashi
KTKazuhiro Tada
Kazuhiro Tada
HHHiroto Hiyamuta
Hiroto Hiyamuta
MWMaho Watanabe
Maho Watanabe
KMKosuke Masutani
Kosuke Masutani
Background The gut bacterial microbiota is altered in patients with chronic kidney disease (CKD). However, the bacterial composition at each stage of CKD is unclear in these patients, including those receiving renal replacement therapy. We herein report the changes in the gut microbiota among patients with CKD. Methods A total of 93 individuals were recruited for the study. Seventy-three patients had stage 3-5 CKD, including those receiving renal replacement therapy (CKD group), and 20 were age- and sex-matched controls (CKD stage 1-2). The gut microbiome composition was analyzed using a 16S ribosomal RNA gene-based sequencing protocol. Results At the genus level, the butyrate-producing bacteria Lachnospira, Blautia, Coprococcus, Anaerostipes, and Roseburia were more abundant in the control group (linear discriminant analysis score of >3) than in the CKD group. Lachnospira was more abundant in the control group than in patients with CKD stage 3a. Compared to the control group, multiplex butyrate-producing bacteria were deficient in patients with CKD stage 3b-5D, including in patients receiving renal replacement therapy. Conclusion Our findings highlight the fact that the gut bacterial composition, including butyrate-producing bacteria, deteriorates from CKD stage 3b. Even after renal replacement therapy, the bacterial composition did not change.