Osamu Yoshida

Dr. Osamu Yoshida


Research Focus & Metrics

Academic Career Length

21Years (2006-Present)

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

Representative Publications

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5 November 2021 in Pathogens
Verified
Journal Article
Open access
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SASheikh Mohammad Fazle Akbar
Sheikh Mohammad Fazle Akbar
MMMamun Al Mahtab
Mamun Al Mahtab
JAJulio Cesar Aguilar
Julio Cesar Aguilar
OYOsamu Yoshida
Osamu Yoshida
EPEduardo Penton
Eduardo Penton
YHYoichi Hiasa
Yoichi Hiasa
A phase III clinical trial in treatment-naïve patients with chronic hepatitis B (CHB) revealed the safety and considerable therapeutic efficacy of a vaccine containing both hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) (NASVAC) at the end of treatment (EOT) and 24 weeks after EOT. Two years after EOT, we checked HBV DNA, alanine aminotransferase (ALT), and hepatitis B e antigen (HBeAg). The data reveal that 33 of 66 NASVAC-recipient CHB patients became negative for HBV DNA in the blood two years after EOT. The ALT levels were within the upper limit of normal (ULN) in 37 patients, although all 66 CHB patients had elevated ALT (above ULN) before the start of therapy. Out of the total twelve HBeAg-positive patients, eight patients became negative for HBeAg. None of the patients developed cirrhosis of the liver within this period. NASVAC is a finite treatment regimen with sustained antiviral and liver-protecting properties. This study is the first to report follow-up data of immune therapy for CHB. NASVAC, an immune therapy of finite duration, is endowed with sustained antiviral and liver protection properties in CHB patients.

30 December 2021 in Vaccines
Verified
Journal Article
Open access
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SASheikh Mohammad Fazle Akbar
Sheikh Mohammad Fazle Akbar
MMMamun Al Mahtab
Mamun Al Mahtab
JAJulio Cesar Aguilar
Julio Cesar Aguilar
OYOsamu Yoshida
Osamu Yoshida
SKSakirul Khan
Sakirul Khan
YHYoichi Hiasa
Yoichi Hiasa
The objective of the present study was to assess the safety and efficacy of a therapeutic vaccine containing both HBsAg and HBcAg (NASVAC) in patients with chronic hepatitis B (CHB) three years after the end of treatment (EOT) as a follow-up of a phase III clinical trial. NASVAC was administered ten times by the nasal route and five times by subcutaneous injection. A total of 59 patients with CHB were enrolled. Adverse events were not seen in any of the patients. Out of the 59 CHB patients, 54 patients exhibited a reduction in HBV DNA, compared with their basal levels. Although all the patients had alanine transaminase (ALT) above the upper limit of normal (>42 IU/L) before the commencement of therapy, the levels of ALT were within the ULN level in 42 patients. No patient developed cirrhosis of the liver. The present study, showing the safety and efficacy of NASVAC 3 years after the EOT, is the first to report follow-up data of an immune therapeutic agent against CHB. NASVAC represents a unique drug against CHB that is safe, of finite duration, can be administered by the nasal route, is capable of reducing HBV DNA and normalizing ALT, and contains hepatic fibrosis.

1 November 2006 in Current Medicinal Chemistry
Verified
Journal Article
Closed access
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SASk. Md.Fazle Akbar
Sk. Md.Fazle Akbar
MAMasanori Abe
Masanori Abe
OYOsamu Yoshida
Osamu Yoshida
HMHidehiro Murakami
Hidehiro Murakami
MOMorikazu Onji
Morikazu Onji
Abstract: Existence of residual cancers and recurrence of cancers are two major limitations of conventional therapies against cancers. A naturally-occurring defense system against tumor may be established in cancer patients by induction of antitumor immunity. Both polyvalent and tumor antigen-defined vaccines have been administered to cancer patients to accomplish this. However, the efficacy of these approaches is not promising. Dendritic cells (DCs) are regulator of the immune system. Antigens loaded on DCs (antigen-pulsed DCs) are able to induce immune responses when this can not be achieved by administration of antigens or vaccines only. Tumor antigen-pulsed DCs are now used for treatment of patients with cancers. But, it is unlikely that the present regimen of DC-based therapy would be an independent anticancer therapeutic approach. However, the therapeutic potentials of tumor antigen-pulsed DCs can be accentuated in cancer patients if this immune therapy is performed as part of multidisciplinary therapeutic approaches. In this review, we will describe about the concept and limitations of the present regimen of tumor antigen-pulsed DC-based therapy in cancer patients. We will further discuss how DC-based therapy can be applied as a multidisciplinary approach to cancer treatment.

22 February 2019 in PLOS ONE
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Journal Article
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YIYusuke Imai
Yusuke Imai
OYOsamu Yoshida
Osamu Yoshida
TWTakao Watanabe
Takao Watanabe
AYAtsushi Yukimoto
Atsushi Yukimoto
YKYohei Koizumi
Yohei Koizumi
YHYoichi Hiasa
Yoichi Hiasa
Hepatic stellate cells (HSCs) were reported to promote the progression of hepatocellular carcinoma (HCC), however its mechanism is uncertain. We previously reported that protein kinase R (PKR) in hepatocytes regulated HCC proliferation. In this study, we focused on the role of PKR in HSCs, and clarified the mechanism of its association with HCC progression. We confirmed the activation of PKR in a human HSC cell line (LX-2 cell). IL-1β is produced from HSCs stimulated by lipopolysaccharide (LPS) or palmitic acid which are likely activators of PKR in non-alcoholic steatohepatitis (NASH). Production was assessed by real-time PCR and ELISA. C16 and small interfering RNA (siRNA) were used to inhibit PKR in HSCs. The HCC cell line (HepG2 cell) was cultured with HSC conditioning medium to assess HCC progression, which was evaluated by proliferation and scratch assays. Expression of PKR was increased and activated in stimulated HSCs, and IL-1β production was also increased molecular. Key molecules of the mitogen-activated protein kinase pathway were also upregulated and activated by LPS. Otherwise, PKR inhibition by C16 and PKR siRNA decreased IL-1β production. HCC progression was promoted by HSC-stimulated conditioning medium although it was reduced by the conditioning medium from PKR-inhibited HSCs. Moreover, palmitic acid also upregulated IL-1β expression in HSCs, and conditioning medium from palmitic acid-stimulated HSCs promoted HCC proliferation. Stimulated HSCs by activators of PKR in NASH could play a role in promoting HCC progression through the production of IL-1β, via a mechanism that seems to be dependent on PKR activation.

12 October 2022 in Biomedicines
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Journal Article
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TKTeru Kumagi
Teru Kumagi
Shinya FurukawaShinya Furukawa
Shinya Furukawa
Bunzo MatsuuraBunzo Matsuura
Bunzo Matsuura
OYOsamu Yoshida
Osamu Yoshida
MMMasumi Miyazaki
Masumi Miyazaki
YHYoichi Hiasa
Yoichi Hiasa
The relationship between advanced nonalcoholic steatohepatitis (NASH) and plasma fatty acid composition remains unknown. We aimed to examine the plasma fatty acid composition in biopsy-confirmed nonalcoholic fatty liver disease (NAFLD) and evaluate the relationship between histological findings and fatty acid composition. Overall, 235 patients (134 women) with NAFLD were enrolled. Comprehensive blood chemistry tests and histological examinations of liver samples were conducted. Multivariate analyses adjusted for age, sex, body mass index, alanine aminotransferase, hemoglobin A1c, creatinine, total cholesterol, triglyceride, and NAFLD Activity Score values showed that lower levels of arachidic, behenic, α-linolenic, eicosatetraenoic, docosapentaenoic, and docosahexaenoic acids and higher levels of mead acid were associated with fibrosis stage 3–4. Furthermore, higher lauric acid, myristic acid, and palmitic acid levels and monounsaturated fatty acids such as palmitoleic acid and oleic acid were significantly associated with high NAS in analyses adjusted for the same factors and fibrosis stage. The plasma fatty acid composition was associated with the histological evidence of NASH. Increased synthesis of fatty acids is associated with NASH; insufficient intake of n-3 essential fatty acids and reduced elongation of fatty acids are associated with fibrosis in NASH. These features may help clinicians to understand and treat advanced NASH cases.

12 April 2021 in Vaccines
Verified
Journal Article
Open access
PDF file
SASheikh Mohammad Fazle Akbar
Sheikh Mohammad Fazle Akbar
MMMamun Al Mahtab
Mamun Al Mahtab
FBFerdousi Begum
Ferdousi Begum
SHShaikh A. Shahed Hossain
Shaikh A. Shahed Hossain
SSSukumar Sarker
Sukumar Sarker
YHYoichi Hiasa
Yoichi Hiasa
The World Health Organization (WHO) South-East Asia Regional Office (SEARO) covers 11 countries with a combined population of about 2 billion people, making it the most populous of the six WHO regions. In 1992, the WHO advocated including the hepatitis B vaccine in the Expanded Program of Immunization (EPI) and vaccinating all infants and children three times within 1 year of birth (HepB3). Recently, the WHO advocate birth-dose hepatitis B vaccination (HepB-BD) as soon as possible after birth, preferably within 24 hours. In 2016, the SEARO endorsed a regional hepatitis B control goal with a target of hepatitis B surface antigen (HBsAg) seroprevalence of ≤1% among children aged ≥5 years by 2020. Of the 11 SEARO countries, four achieved this target on schedule. Out of these four countries, two countries (Bangladesh and Nepal) have not adopted HepB-BD in EPI program. On the other hand, the coverage of HepB3 is not satisfactory in some SEARO countries, including India which adopted HepB-BD but could not achieve the overall target of SEARO. Thus, it is a point of debate whether emphasis should be placed on proper implementation of HepB3 or whether a new agenda of HepB-BD should be incorporated in developing countries of SEARO. The article discusses strengthening and expanding the Hepatitis B vaccination program in SEARO countries with an emphasis on HepB and HepB-BD programs.