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Featured researches published by Seiji Kageyama.


Antiviral Research | 1996

THERAPEUTIC BASIS OF GLYCYRRHIZIN ON CHRONIC HEPATITIS B

Hitoshi Sato; Wakana Goto; Jun-ichi Yamamura; Masahiko Kurokawa; Seiji Kageyama; Terumi Takahara; Akiharu Watanabe; Kimiyasu Shiraki

Glycyrrhizin, a major component of a herb (licorice), has been intravenously used for the treatment of chronic hepatitis B in Japan and improves liver function with occasional complete recovery from hepatitis. This substance modifies the intracellular transport and suppresses sialylation of hepatitis B virus (HBV) surface antigen (HBsAg) in vitro. This study was designed to clarify the pharmacological basis for its effectiveness. The structure-bioactivity relationship of glycyrrhizin, glycyrrhetic acid 3-O-monoglucuronide and glycyrrhetic acid was determined, and glycyrrhetic acid was found to be the most active of them. The amounts of three substances bound to the liver were evaluated in guinea pigs after intravenous administration of glycyrrhizin. Glycyrrhizin and glycyrrhetic acid 3-O-monoglucuronide were detected at concentrations of 31.8-1.3 micrograms/g of liver, but glycyrrhetic acid was not detected. When glycyrrhizin attained these concentrations in the cellular fraction of the PLC/PRF/5 cell culture, it suppressed the secretion of HBsAg as reported previously. These results indicated that glycyrrhizin administered intravenously might bind to hepatocytes at the concentration at which glycyrrhizin could modify the expression of HBV-related antigens on the hepatocytes and suppress sialylation of HBsAg.


Antiviral Research | 1996

Prophylactic treatment of cytomegalovirus infection with traditional herbs

Tomoyo A. Yukawa; Masahiko Kurokawa; Hitoshi Sato; Yoshihiro Yoshida; Seiji Kageyama; Tomomi Hasegawa; Tuneo Namba; Masami Imakita; Toyoharu Hozumi; Kimiyasu Shiraki

Hot water extracts of four traditional herbs, Geum japonicum, Syzygium aromaticum, Terminalia chebula and Rhus javanica, which have been shown to have anti-herpes simplex virus (HSV) activity in vivo, were examined for anti-cytomegalovirus (CMV) activity in vitro and in vivo in this study. They inhibited replication of human CMV and murine CMV (MCMV) in vitro. These anti-CMV activities in vivo were examined in an MCMV infection model using immunosuppressed mice. Mice were subcutaneously treated with various doses of cyclosporine, and immunosuppression and MCMV infection were monitored by suppression of antibody production and virus yield in the lung, respectively. Each herbal extract was orally administered to mice treated with 50 mg/kg of cyclosporine from a day before intraperitoneal infection, and the efficacy of herbs was evaluated by the reduction in the virus yield in the lung. Among them Geum japonicum, Syzygium aromaticum, and Terminalia chebula significantly suppressed MCMV yields in lungs of treated mice compared with water treatment. Efficacy of oral treatment with 750 mg/kg per day of Geum japonicum extract was similar to that of the intraperitoneal administration of 2 mg/kg per day of ganciclovir in increasing the body weight of infected mice and reducing the virus yield in the lungs. These herbs may be beneficial for the prophylaxis of CMV diseases in immunocompromised patients.


Journal of Acquired Immune Deficiency Syndromes | 2004

Genetic diversity of HIV type 1 in rural eastern Cameroon.

Nicaise Ndembi; Jun Takehisa; Leopold Zekeng; Eiji Kobayashi; Charlotte Ngansop; Elijah M. Songok; Seiji Kageyama; Taichiro Takemura; Eiji Ido; Masanori Hayami; Lazare Kaptue; Hiroshi Ichimura

To monitor the presence of genotypic HIV-1 variants circulating in eastern Cameroon, blood samples from 57 HIV-1-infected individuals attending 3 local health centers in the bordering rural villages with Central African Republic (CAR) were collected and analyzed phylogenetically. Out of the 40 HIV-1 strains with positive polymerase chain reaction (PCR) profile for both gag and env-C2V3,12 (30.0%) had discordant subtype or CRF designation: 2 subtype B/A (gag/env), 1 B/CRF01, 2 B/CRF02, 1 CRF01/CRF01.A, 2 CRF11/CRF01, 1 CRF13/A, 1 CRF13/CRF01, 1 CRF13/CRF11, and 1 G/U (unclassified). Twenty-eight strains (70.0%) had concordant subtypes or CRF designation between gag and env: 27 subtype A and 1 F2. Out of the remaining 17HIV-1 strains negative for PCR with the env-C2V3 primers used, 10 (58.8%) had discordant subtype or CRF, and 7 (41.2%) had concordant one based on gag/pol/env-gp41 analysis. Altogether, a high proportion (22/57, 38.6%) of the isolates were found to be recombinant strains. In addition, an emergence of new forms of HIV-1 strains, such as subtype B/A (gag/env), B/CRF01 and B/CRF02, was identified. The epidemiologic pattern of HIV-1 in eastern Cameroon, relatively low and high prevalence of CRF02 and CRF11, respectively, was more closely related to those of CAR and Chad than that of other regions of Cameroon, where CRF02 is the most predominant HIV-1 strain. These findings strongly suggest that this part of Cameroon is a potential hotspot of HIV-1 recombination, with a likelihood of an active generation of new forms of HIV-1 variants, though epidemiologic significance of new HIV-1 forms is unknown.


Antiviral Research | 1999

Emergence of resistance to acyclovir and penciclovir in varicella-zoster virus and genetic analysis of acyclovir-resistant variants.

Mitsuru Ida; Seiji Kageyama; Hitoshi Sato; Tomoko Kamiyama; Jun-ichi Yamamura; Masahiko Kurokawa; Masaaki Morohashi; Kimiyasu Shiraki

We have characterized the differential actions of acyclovir and penciclovir against varicella-zoster virus (VZV) in cell culture by comparing the frequency of appearance of resistant viruses followed by their characterization. Cells were infected with cell-free virus and the cultures were successively treated with increasing concentrations of acyclovir or penciclovir. Drug-resistant viruses were selected in the presence of 6 microg/ml of acyclovir or penciclovir. The emergence frequency of resistant viruses was significantly higher following acyclovir exposure than following penciclovir exposure (Fishers exact test, P<0.0001), possibly reflecting virus growth differences under these experimental conditions. Based on antiviral drug susceptibility and thymidine kinase (TK) activity assays, 11 acyclovir-resistant variants from seven experiments using three virus strains (Kawaguchi strain, Oka varicella vaccine strain and a clinical isolate from a zoster patient) were found to be TK-deficient. Sequence analysis of TK-deficient variants of the Kawaguchi strain revealed deletions that caused frameshifts, resulting in premature termination in the TK gene.


AIDS Research and Human Retroviruses | 2009

Profile of HIV Type 1 Infection and Genotypic Resistance Mutations to Antiretroviral Drugs in Treatment-Naive HIV Type 1-Infected Individuals in Hai Phong, Viet Nam

Azumi Ishizaki; Nguyen Hung Cuong; Pham Van Thuc; Nguyen Vu Trung; Kiyofumi Saijoh; Seiji Kageyama; Kyoko Ishigaki; Junko Tanuma; Shinichi Oka; Hiroshi Ichimura

We evaluated the prevalence and profile of antiretroviral treatment (ART)-associated resistance mutations among HIV-1 strains in northern Vietnam by genotypically analyzing strains isolated from ART-naive individuals in Hai Phong, a city in which HIV-1 is highly prevalent. Plasma samples were collected from injecting drug users (IDU, n = 760), female sex workers (FSW, n = 91), seafarers (n = 94), pregnant women (n = 200), and blood donors (n = 210), and screened for HIV-1 antibodies. Plasma viral RNA was extracted from HIV-1-positive samples, amplified by reverse transcriptase (RT)-PCR of protease and RT genes, and analyzed for genotypes and ART-associated resistance mutations. HIV-1 prevalence among IDU, FSW, seafarers, pregnant women, and blood donors was 35.9%, 23.1%, 0%, 0.5%, and 2.9%, respectively. Phylogenetic analyses revealed that the most prevalent HIV-1 subtype was CRF01_AE (98.3%), similar to strains prevalent in southern China. Four (1.4%) subtype B strains and one (0.3%) unique recombinant between subtypes B and C were also identified. We found protease inhibitor-associated major resistance mutations in one of the 294 cases analyzed (0.3%; mutation M46I). We found RT inhibitor-associated major resistance mutations in 7/273 cases (2.6%; one occurrence each of L74I, M184I, and K219E; three cases of K103N; and two cases of G190E). One CRF01_AE strain harboring a protease codon 35 insertion was first identified in Vietnam. Thus, monitoring of drug-resistant HIV-1 and establishment of a database are required for the proper selection of ART in Vietnam.


Journal of Acquired Immune Deficiency Syndromes | 2006

Emergence of antiretroviral therapy resistance-associated primary mutations among drug-naive HIV-1-infected individuals in rural western cameroon

Yusuke Koizumi; Nicaise Ndembi; Michiko Miyashita; Raphael Lwembe; Seiji Kageyama; Dora Mbanya; Lazare Kaptue; Kei Numazaki; Yoshihide Fujiyama; Hiroshi Ichimura

Summary: The prevalence of antiretroviral therapy (ART) resistance-associated mutations among HIV-1 strains in western Cameroon was evaluated by genotypically analyzing strains isolated from drug-naive individuals. Proviral DNA was extracted from 54 blood samples and amplified by polymerase chain reaction of protease, reverse transcriptase, integrase, and envelope genes. At least 4 clones per sample were analyzed. Of 54 HIV-1 strains, 45 (83.3%) had a concordant subtype or circulating recombinant form (CRF) designation: 40 CRF02_AG, 2 subtype A1, 2 G, and 1 F2. The remaining 9 (16.7%) had a discordant subtype: 6 subtype A1/CRF02_AG, 2 D/CRF02, and 1 G/CRF02. Protease inhibitor-associated primary resistance mutations were found in 4 (7.4%) cases: M46L with full clones in 1 case, and M46I, M46L, and V82A as minor populations in 1 case each. Reverse transcriptase inhibitor-associated primary resistance mutations were found in 5 (9.8%) samples: Y188C in 2 cases, and L100I, M184V, and V75I in 1 case each, although all of these mutations were found as minor populations. This is one of the first reports of the emergence of primary ART resistance mutations among drug-naive, non-B subtype HIV-1-infected individuals in Cameroon. Follow-up studies should be conducted to assess whether these drug-resistant mutants found as minor populations might impact future ART.


Journal of Infection in Developing Countries | 2013

Molecular epidemiology of HIV, HBV, HCV, and HTLV-1/2 in drug abuser inmates in central Javan prisons, Indonesia

Afiono Agung Prasetyo; Paramasari Dirgahayu; Yulia Sari; Seiji Kageyama

INTRODUCTION This study was conducted to determine the current molecular prevalence of human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV), and human T lymphotropic virus-1/2 (HTLV-1/2) circulating among drug abuser inmates incarcerated in prisons located in Central Java, Indonesia. METHODOLOGY Socio-epidemiological data and blood specimens were collected from 375 drug abuser inmates in four prisons. The blood samples were analyzed with serological and molecular testing for HIV, HBV, HCV, HDV, and HTLV-1/2. RESULTS The seroprevalence of HIV, HBsAg, HCV, HDV, and HTLV-1/2 in drug abuser inmates was 4.8% (18/375), 3.2% (12/375), 34.1% (128/375), 0% (0/375), and 3.7% (14/375), respectively. No co-infections of HIV and HBV were found. Co-infections of HIV/HCV, HIV/HTLV-1/2, HBV/HCV, HBV/HTLV-1/2, and HCV/HTLV-1/2 were prevalent at rates of 4% (15/375), 1.3% (5/375), 1.1% (4/375), 0.3% (1/375), and 2.1% (8/375), respectively. The HIV/HCV co-infection rate was significantly higher in injection drug users (IDUs) compared to non-IDUs. Triple co-infection of HIV/HCV/HTLV-1/2 was found only in three IDUs (0.8%). HIV CRF01_AE was found to be circulating in the inmates. HBV genotype B3 predominated, followed by C1. Subtypes adw and adr were found. HCV genotype 1a predominated among HCV-infected inmates, followed by 1c, 3k, 3a, 4a, and 1b. All HTLV-1 isolates shared 100% homology with HTLV-1 isolated in Japan, while all of the HTLV-2 isolates were subtype 2a. CONCLUSION Drug abuser inmates in prisons may offer a unique community to bridge prevention and control of human blood-borne virus infection to the general community.


Journal of Medical Virology | 2009

High-risk HPV types in lesions of the uterine cervix of female commercial sex workers in the Philippines.

Michiko Miyashita; Dorothy M. Agdamag; Toshiyuki Sasagawa; Kaori Matsushita; Lourdes Ma. Salud; Calixto O. Salud; Kunikazu Saikawa; Prisca Susan A. Leano; Teresita Pagcaliwagan; Jessica Acuna; Azumi Ishizaki; Seiji Kageyama; Hiroshi Ichimura

In order to prevent cervical cancer, vaccines against human papilloma virus types 16 (HPV‐16) and 18 (HPV‐18) have been implemented worldwide. However, the HPV types that cause cancer can differ according to geographical area and ethnicity. In this new era of the HPV vaccine, it is important to elucidate the prevalent HPV types in each area. Therefore, the prevalence of HPV infection and cervical abnormalities among 369 female commercial sex workers in the Philippines were examined. HPV L1 gene was amplified by polymerase chain reaction (PCR) using modified GP5+/6+ primers, and genotyping was performed by sequencing cloned PCR products. HPV DNA was detected in 211 (57.2%) women, among whom 46 HPV types were identified. HPV‐52 was most common and multiple‐type infection was observed in 44.5%. Among 56 women with abnormal cervical cytology (low‐ and high‐grade squamous intraepithelial lesions and adenocarcinoma in situ), HPV‐52 was most common (23.2%), followed by HPV‐16 (19.6%), ‐58 (10.7%), and ‐67 (10.7%). Only 27% of these women were positive for HPV‐16 and ‐18. Multivariate analysis revealed that HPV‐16, ‐39, ‐52, ‐67, and ‐82 were significantly associated with abnormal cytology. Repeated analysis of HPV‐52 single‐positive samples using the original GP5+/6+ PCR primers produced negative results in 57% of cases, suggesting that the prevalence of HPV‐52 infection may have been underestimated in previous studies, and the current vaccines may not be sufficient for preventing infection and the development of premalignant lesions of the cervix in women in the Philippines. J. Med. Virol. 81:545–551, 2009.


Journal of Medical Virology | 2010

Multiple routes of hepatitis C virus transmission among injection drug users in Hai Phong, Northern Vietnam.

Tomoaki Tanimoto; Nguyen Hung Cuong; Azumi Ishizaki; Phan Thi Thu Chung; Hoang Thi Thanh Huyen; Nguyen Vu Trung; Seiji Kageyama; Shinichi Oka; Pham Van Thuc; Hiroshi Ichimura

To identify hepatitis C virus (HCV) transmission routes among injection drug users in Northern Vietnam, plasma samples were collected from 486 drug users in Hai Phong. Plasma viral RNA was extracted from 323 (66.5%) samples that were positive for anti‐HCV antibodies. Portions of the HCV 5′‐untranslated (5′UTR)‐Core and NS5B genes were amplified by reverse‐transcriptase polymerase chain reaction, sequenced directly, and genotyped in 194 and 195 specimens, respectively. Both regions were genotyped in 137 specimens. In the 5′UTR‐Core region, genotype 6a was predominant (32.5%), followed by genotype 1a (23.7%), genotype 1b (20.6%), and genotype 6e (14.4%). In the NS5B region, genotype 1a was predominant (42.6%), followed by genotype 1b (24.1%), genotype 6a (14.4%), genotype 3b (7.2%), and genotype 6e (5.1%). Of the 137 specimens with both regions genotyped, 23 (16.8%) showed discordant genotyping results between the two regions, suggesting possible recombination and/or dual infection. Phylogenetic analysis revealed close associations between Hai Phong strains and strains from Southern China: the Yunnan province for genotype 3b; the Guangxi province for genotype 6e; the USA for genotype 1a; and Southern Vietnam for genotypes 1a and 6e. The human immunodeficiency virus (HIV) infection rate among HCV‐infected injection drug users was 52.6–55.4% and did not differ significantly by HCV genotype. Most drug users infected with HIV‐1 [98.8% (171/173)] were co‐infected with HCV. These results suggest multiple routes of HCV transmission among injection drug users in Northern Vietnam that may also be HIV transmission routes. J. Med. Virol. 82:1355–1363, 2010.


Journal of Dermatological Science | 1997

Prophylactic efficacy of traditional herbal medicines against recurrent herpes simplex virus type 1 infection from latently infected ganglia in mice

Masahiko Kurokawa; Michio Nakano; Haruo Ohyama; Toyoharu Hozumi; Seiji Kageyama; Tsuneo Namba; Kimiyasu Shiraki

Traditional herbal medicines with anti-herpes simplex virus type 1 (HSV-1) activity in vivo were examined for their prophylactic effects on recurrent HSV-1 infection in mice. Mice were intradermally infected with HSV-1 in the pinna and recurrent HSV-1 disease was induced by ultraviolet irradiation. Herbal extracts arrested the progression of recurrent HSV-1 disease, reduced the incidence of severe erythema and/or vesicles in the pinna, and/or shortened the period of severe recurrent lesions compared with water-administered mice (P < 0.01 or 0.05). Similarly, the prophylactic treatment of herbal extracts limited the development of recurrent skin lesions induced by stripping with cellophane tape physically. The prophylactic efficacy on recurrence was confirmed by the absence of HSV DNA in the skin lesions. HSV-1 genome was revealed to exist in the trigeminal ganglia but not in the pinna of latently infected mice before stimuli by a nested-polymerase chain reaction assay. After stimuli, HSV-1 genome was detected in both pinna and trigeminal ganglia of latently infected mice administered with water. However, prophylactic treatment decreased the rate of detection of HSV-1 genome in the stimulated pinna. Thus, the herbal extracts exhibited prophylactic efficacy against recurrent HSV-1 disease in mice and modulated the recurrent HSV-1 infection.

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Hitoshi Sato

Kanazawa Medical University

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Masahiko Kurokawa

Kyushu University of Health and Welfare

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Jun-ichi Yamamura

Kanazawa Medical University

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Raphael Lwembe

Kenya Medical Research Institute

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