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1.
J Virol ; 95(5)2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33298539

RESUMO

Hepatitis B virus (HBV) infection is a major public health problem. Human hepatocytes are infected with HBV via binding between the preS1 region in the large envelope protein of HBV and sodium taurocholate cotransporting polypeptide. Although several monoclonal antibodies (MAbs) that recognize the receptor binding domain in preS1 and neutralize HBV infection have been isolated, details of neutralizing epitopes are not understood. In this study, we generated 13 MAbs targeting the preS1 receptor binding domain from preS1-specific memory B cells derived from DNA immunized mice. The MAbs were classified into three groups according to the epitope regions, designated epitopes I-III. A virus neutralization assay revealed that MAbs recognizing epitopes I and III neutralized HBV infection, suggesting that these domains are critical epitopes for viral neutralization. In addition, a neutralization assay against multiple genotypes of HBV revealed that epitope I is a semi-pangenotypic neutralizing epitope, whereas epitope III is a genotype-specific epitope. We also showed that neutralizing MAbs against preS1 could neutralize HBV bearing vaccine-induced escape mutation. These findings provide insight into novel immunoprophylaxis for the prevention and treatment of HBV infection.IMPORTANCE The HBV preS1 2-47 aa region (preS1/2-47) is essential for virus binding with sodium taurocholate cotransporting polypeptide. Several MAbs targeting preS1/2-47 have been reported to neutralize HBV infection; however, which region in preS1/2-47 contains the critical neutralizing epitope for HBV infection is unclear. Here, we generated several MAbs targeting preS1/2-47 and found that MAbs recognizing the N- or C-terminus of preS1/2-47 remarkably neutralized HBV infection. We further confirmed the neutralizing activity of anti-preS1 MAbs against HBV with vaccine escape mutation. These data clarified the relationship between the antibody epitope and the virus neutralizing activity and also suggested the potential ability of a vaccine antigen containing the preS1 region to overcome the weakness of current HB vaccines comprising the small S protein.

2.
PLoS Pathog ; 16(7): e1008619, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32614892

RESUMO

Norovirus is the major cause of epidemic nonbacterial gastroenteritis worldwide. Lack of structural information on infection and replication mechanisms hampers the development of effective vaccines and remedies. Here, using cryo-electron microscopy, we show that the capsid structure of murine noroviruses changes in response to aqueous conditions. By twisting the flexible hinge connecting two domains, the protruding (P) domain reversibly rises off the shell (S) domain in solutions of higher pH, but rests on the S domain in solutions of lower pH. Metal ions help to stabilize the resting conformation in this process. Furthermore, in the resting conformation, the cellular receptor CD300lf is readily accessible, and thus infection efficiency is significantly enhanced. Two similar P domain conformations were also found simultaneously in the human norovirus GII.3 capsid, although the mechanism of the conformational change is not yet clear. These results provide new insights into the mechanisms of non-enveloped norovirus transmission that invades host cells, replicates, and sometimes escapes the hosts immune system, through dramatic environmental changes in the gastrointestinal tract.


Assuntos
Proteínas do Capsídeo/química , Norovirus/química , Domínios Proteicos , Animais , Linhagem Celular , Humanos , Camundongos
3.
J Virol ; 94(2)2020 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-31645450

RESUMO

A number of positive-strand RNA viruses, such as hepatitis C virus (HCV) and poliovirus, use double-membrane vesicles (DMVs) as replication sites. However, the role of cellular proteins in DMV formation during virus replication is poorly understood. HCV NS4B protein induces the formation of a "membranous web" structure that provides a platform for the assembly of viral replication complexes. Our previous screen of NS4B-associated host membrane proteins by dual-affinity purification, liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), and small interfering RNA (siRNA) methods revealed that the Surfeit 4 (Surf4) gene, which encodes an integral membrane protein, is involved in the replication of the JFH1 subgenomic replicon. Here, we investigated in detail the effect of Surf4 on HCV replication. Surf4 affects HCV replication in a genotype-independent manner, whereas HCV replication does not alter Surf4 expression. The influence of Surf4 on HCV replication indicates that while Surf4 regulates replication, it has no effect on entry, translation, assembly, or release. Analysis of the underlying mechanism showed that Surf4 is recruited into HCV RNA replication complexes by NS4B and is involved in the formation of DMVs and the structural integrity of RNA replication complexes. Surf4 also participates in the replication of poliovirus, which uses DMVs as replication sites, but it has no effect on the replication of dengue virus, which uses invaginated/sphere-type vesicles as replication sites. These findings clearly show that Surf4 is a novel cofactor that is involved in the replication of positive-strand RNA viruses using DMVs as RNA replication sites, which provides valuable clues for DMV formation during positive-strand RNA virus replication.IMPORTANCE Hepatitis C virus (HCV) NS4B protein induces the formation of a membranous web (MW) structure that provides a platform for the assembly of viral replication complexes. The main constituents of the MW are double-membrane vesicles (DMVs). Here, we found that the cellular protein Surf4, which maintains endoplasmic reticulum (ER)-Golgi intermediate compartments and the Golgi compartment, is recruited into HCV RNA replication complexes by NS4B and is involved in the formation of DMVs. Moreover, Surf4 participates in the replication of poliovirus, which uses DMVs as replication sites, but has no effect on the replication of dengue virus, which uses invaginated vesicles as replication sites. These results indicate that the cellular protein Surf4 is involved in the replication of positive-strand RNA viruses that use DMVs as RNA replication sites, providing new insights into DMV formation during virus replication and potential targets for the diagnosis and treatment of positive-strand RNA viruses.


Assuntos
Estruturas da Membrana Celular/metabolismo , Hepacivirus/fisiologia , Proteínas de Membrana/metabolismo , RNA Viral/biossíntese , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/fisiologia , Linhagem Celular Tumoral , Estruturas da Membrana Celular/genética , Estruturas da Membrana Celular/virologia , Genótipo , Humanos , Proteínas de Membrana/genética , RNA Viral/genética , Proteínas não Estruturais Virais/genética
4.
J Immunol ; 203(12): 3282-3292, 2019 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-31704880

RESUMO

Virus-like particles (VLPs) provide a well-established vaccine platform; however, the immunogenic properties acquired by VLP structure remain poorly understood. In this study, we showed that systemic vaccination with norovirus VLP recalls human IgA responses at higher magnitudes than IgG responses under a humanized mouse model that was established by introducing human PBMCs in severely immunodeficient mice. The recall responses elicited by VLP vaccines depended on VLP structure and the disruption of VLP attenuated recall responses, with a more profound reduction being observed in IgA responses. The IgA-focusing property was also conserved in a murine norovirus-primed model under which murine IgA responses were recalled in a manner dependent on VLP structure. Importantly, the VLP-driven IgA response preferentially targeted virus-neutralizing epitopes located in the receptor-binding domain. Consequently, VLP-driven IgA responses were qualitatively superior to IgG responses in terms of the virus-neutralizing activity in vitro. Furthermore, the IgA in mucosa obtained remarkable protective function toward orally administrated virus in vivo. Thus, our results indicate the immune-focusing properties of the VLP vaccine that improve the quality/quantity of mucosal IgA responses, a finding with important implications for developing mucosal vaccines.


Assuntos
Anticorpos Antivirais/imunologia , Imunoglobulina A/imunologia , Vacinas de Partículas Semelhantes a Vírus/imunologia , Animais , Formação de Anticorpos/imunologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Infecções por Caliciviridae/prevenção & controle , Humanos , Imunidade nas Mucosas , Switching de Imunoglobulina/genética , Switching de Imunoglobulina/imunologia , Imunoglobulina G/imunologia , Memória Imunológica , Camundongos , Camundongos Transgênicos , Norovirus/imunologia
5.
Sci Rep ; 9(1): 7446, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31092854

RESUMO

Observations of fractional quantum Hall (FQH) plateaus are reported in bilayer electron gas system in wide (>80 nm) In0.75Ga0.25As wells. Several q/p (p = 5, 3, and 2, q > 5) QH states are confirmed at high temperatures (~1.6 K) when the critical conditions including an electron density imbalance as well as a dynamical resistance behavior at the bilayer-monolayer transition are properly satisfied. The former leads to a quantum limit in either of the layers and the latter might bring a meta-stable nature into FQH phenomena. Such a behavior occurs as a probability process associating with impurities or defects in the wells, they inevitably reflect the local structural landscapes of each sample. This is verified by the new finding that the kinds of fractional plateaus (what set of fractional filling factors) appeared are different depending on the samples, that is, they are the "finger print" in each sample.

6.
Front Immunol ; 9: 47, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29416543

RESUMO

The influenza virus causes annual epidemics and occasional pandemics and is thus a major public health problem. Development of vaccines and antiviral drugs is essential for controlling influenza virus infection. We previously demonstrated the use of vectored immune-prophylaxis against influenza virus infection. We generated a plasmid encoding neutralizing IgG monoclonal antibodies (mAbs) against A/PR/8/34 influenza virus (IAV) hemagglutinin (HA). We then performed electroporation of the plasmid encoding neutralizing mAbs (EP) in mice muscles and succeeded in inducing the expression of neutralizing antibodies in mouse serum. This therapy has a prophylactic effect against lethal IAV infection in mice. In this study, we established a new method of passive immunotherapy after IAV infection. We performed hydrodynamic injection of the plasmid encoding neutralizing mAbs (HD) involving rapid injection of a large volume of plasmid-DNA solution into mice via the tail vein. HD could induce neutralizing antibodies in the serum and in several mucosal tissues more rapidly than in EP. We also showed that a single HD completely protected the mice even after infection with a lethal dose of IAV. We also established other isotypes of anti-HA antibody (IgA, IgM, IgD, and IgE) and showed that like anti-HA IgG, anti-HA IgA was also effective at combating upper respiratory tract IAV infection. Passive immunotherapy with HD could thus provide a new therapeutic strategy targeting influenza virus infection.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Vacinas contra Influenza/administração & dosagem , Infecções por Orthomyxoviridae/terapia , Animais , Anticorpos Neutralizantes/genética , Anticorpos Antivirais/genética , Eletroporação , Feminino , Hidrodinâmica , Imunização Passiva , Injeções , Camundongos Endogâmicos BALB C , Plasmídeos , Mucosa Respiratória/imunologia , Mucosa Respiratória/virologia
7.
J Electromyogr Kinesiol ; 39: 99-103, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29475131

RESUMO

In hemiparetic stroke survivors, premature plantarflexor muscle activity (PPF) often appears as a gait abnormality from terminal swing to the loading response on the paretic side. This study aimed to discern factors giving rise to PPF. Lower extremity function, spasticity magnitude, and gait electromyograms were assessed in 31 hemiparetic stroke survivors. Mean amplitudes during gait phases were determined for the paretic soleus, tibialis anterior, rectus femoris, and biceps femoris. The subjects were classified into PPF and non-PPF groups based on their relative soleus amplitude at different phases of gait, and group differences in each measurement were calculated and subjected to logistic regression. The PPF group showed less activity of the tibialis anterior during the swing phase but greater activity of the rectus femoris during the swing phase and of the biceps femoris, both prematurely and during the loading response. Logistic regression revealed premature activity of the biceps femoris to be a significant variable related to presence of PPF (odds ratio = 1.054). PPF in hemiparetic gait may work with the biceps femoris to supplement compromised lower extremity extension strength. PPF might be reduced by attaining enhanced strength of the hip and knee extensors at the time of initial contact during gait.


Assuntos
Transtornos Neurológicos da Marcha/fisiopatologia , Músculo Esquelético/fisiopatologia , Paresia/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Adulto , Idoso , Eletromiografia/métodos , Feminino , Marcha/fisiologia , Transtornos Neurológicos da Marcha/diagnóstico , Transtornos Neurológicos da Marcha/etiologia , Humanos , Joelho/fisiopatologia , Articulação do Joelho/fisiopatologia , Extremidade Inferior/fisiopatologia , Masculino , Pessoa de Meia-Idade , Espasticidade Muscular/fisiopatologia , Paresia/diagnóstico , Paresia/etiologia , Músculo Quadríceps/fisiopatologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico , Reabilitação do Acidente Vascular Cerebral
8.
Biologicals ; 52: 12-17, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29475730

RESUMO

Slc:Wistar rats have been the only strain used in Japan for purpose of evaluating a national reference vaccine for the Sabin-derived inactivated polio vaccine (sIPV) and the immunogenicity of sIPV-containing products. However, following the discovery that the Slc:Wistar strain was genetically related to the Fischer 344 strain, other "real" Wistar strains, such as Crlj:WI, that are available worldwide were tested in terms of their usefulness in evaluating the immunogenicity of the past and current lots of a national reference vaccine. The response of the Crlj:WI rats against the serotype 1 of sIPV was comparable to that of the Slc:Wistar rats, while the Crlj:WI rats exhibited a higher level of response against the serotypes 2 and 3. The immunogenic potency units of a national reference vaccine determined using the Slc:Wistar rats were reproduced on tests using the Crlj:WI rats. These results indicate that a titer of the neutralizing antibody obtained in response to a given dose of sIPV cannot be directly compared between these two rat strains, but that, more importantly, the potency units are almost equivalent for the two rat strains.


Assuntos
Imunogenicidade da Vacina , Vacina Antipólio Oral/imunologia , Sorogrupo , Animais , Ratos , Ratos Endogâmicos F344 , Ratos Wistar , Especificidade da Espécie
9.
Infect Genet Evol ; 54: 417-428, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28750901

RESUMO

Rotavirus A (RVA) is the predominant etiological agent of acute gastroenteritis in young children worldwide. Recently, unusual G9P[4] rotavirus strains emerged with high prevalence in many countries. Such intergenogroup reassortant strains highlight the ongoing spread of unusual rotavirus strains throughout Asia. This study was undertaken to determine the whole genome of eleven unusual G9P[4] strains detected in India during 2011-2013, and to compare them with other human and animal global RVAs to understand the exact origin of unusual G9P[4] circulating in India and other countries worldwide. Of these 11 RVAs, four G9P[4] strains were double-reassortants with the G9-VP7 and E6-NSP4 genes on a DS-1-like genetic backbone (G9-P[4]-I2-R2-C2-M2-A2-N2-T2-E6-H2). The other strains showed a complex genetic constellation, likely derived from triple reassortment event with the G9-VP7, N1-NSP2 and E6-NSP4 on a DS-1-like genetic backbone (G9-P[4]-I2-R2-C2-M2-A2-N1-T2-E6-H2). Presumably, these unusual G9P[4] strains were generated after several reassortment events between the contemporary co-circulating human rotavirus strains. Moreover, the point mutation S291L at the interaction site between inner and outer capsid proteins of VP6 gene may be important in the rapid spread of this unusual strain. The complex reassortment events within the G9[4] strains may be related to the high prevalence of mixed infections in India as reported in this study and other previous studies.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Vírus Reordenados/genética , Infecções por Rotavirus/virologia , Rotavirus/genética , Análise de Sequência de RNA/métodos , Pré-Escolar , Fezes/virologia , Feminino , Genoma Viral , Humanos , Índia , Lactente , Recém-Nascido , Masculino , Filogenia , Mutação Puntual , Vírus Reordenados/classificação , Vírus Reordenados/isolamento & purificação , Rotavirus/classificação , Rotavirus/isolamento & purificação
10.
Clin Exp Nephrol ; 21(3): 417-424, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27392909

RESUMO

BACKGROUND: Dyslipidemia is a risk factor for the progression of chronic kidney disease (CKD). While conventional lipid lowering therapy provides a benefit to CKD management, the effect of statins on eGFR remains unclear. METHODS: A prospective, multi-center, open-labeled, randomized trial. Total of 349 CKD patients with hyperlipidemia were randomized into 2 groups, and followed for 2 years. Group A included patients who were treated with atorvastatin. Group C were treated with conventional lipid lowering drugs other than statin. Primary endpoint was changes in eGFR. Secondary endpoints included changes in urinary albumin excretion, serum LDL-C, serum triglyceride, cardio-vascular events and all-cause mortality. RESULTS: As the primary endpoint, eGFR decreased by 2.3 ml/min/1.73 m2 in Group A and by 2.6 ml/min/1.73 m2 in Group C, indicating that there was no difference in change of eGFR between the two groups. As secondary endpoints, atorvastatin succeeded to reduce serum LDL-C level significantly and rapidly, but conventional therapy did not. In fact, mean LDL-C level did not reach the target level of 100 mg/dl in Group C. Serum triglyceride was lowered only by atorvastatin, but not conventional drugs. The number of cardiovascular events and all-cause mortality did not differ between in two groups. CONCLUSION: The ASUCA (Assessment of Clinical Usefulness in CKD Patients with Atorvastatin) trial demonstrated that atorvastatin failed to exhibit reno-protections compared to conventional therapy in Japanese patients with dyslipidemia and CKD. It would be due in part to the ability of atorvastatin to more potently reduce serum LDL and triglycerides compared to conventional therapy.


Assuntos
Atorvastatina/uso terapêutico , Dislipidemias/tratamento farmacológico , Taxa de Filtração Glomerular/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Rim/efeitos dos fármacos , Lipídeos/sangue , Insuficiência Renal Crônica/fisiopatologia , Adulto , Idoso , Biomarcadores/sangue , Dislipidemias/sangue , Dislipidemias/complicações , Dislipidemias/mortalidade , Feminino , Humanos , Japão , Rim/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/mortalidade , Fatores de Tempo , Resultado do Tratamento
11.
Proc Natl Acad Sci U S A ; 113(41): E6248-E6255, 2016 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-27681626

RESUMO

Norovirus is the leading cause of acute gastroenteritis worldwide. Since the discovery of human norovirus (HuNoV), an efficient and reproducible norovirus replication system has not been established in cultured cells. Although limited amounts of virus particles can be produced when the HuNoV genome is directly transfected into cells, the HuNoV cycle of infection has not been successfully reproduced in any currently available cell-culture system. Those results imply that the identification of a functional cell-surface receptor for norovirus might be the key to establishing a norovirus culture system. Using a genome-wide CRISPR/Cas9 guide RNA library, we identified murine CD300lf and CD300ld as functional receptors for murine norovirus (MNV). The treatment of susceptible cells with polyclonal antibody against CD300lf significantly reduced the production of viral progeny. Additionally, ectopic CD300lf expression in nonsusceptible cell lines derived from other animal species enabled MNV infection and progeny production, suggesting that CD300lf has potential for dictating MNV host tropism. Furthermore, CD300ld, which has an amino acid sequence in the N-terminal region of its extracellular domain that is highly homologous to that of CD300lf, also functions as a receptor for MNV. Our results indicate that direct interaction of MNV with two cell-surface molecules, CD300lf and CD300ld, dictates permissive noroviral infection.


Assuntos
Interações Hospedeiro-Patógeno/genética , Norovirus/fisiologia , Receptores Imunológicos/genética , Receptores Virais/genética , Sequência de Aminoácidos , Animais , Infecções por Caliciviridae/genética , Infecções por Caliciviridae/metabolismo , Infecções por Caliciviridae/virologia , Proteínas do Capsídeo/química , Proteínas do Capsídeo/metabolismo , Linhagem Celular , Células Cultivadas , Suscetibilidade a Doenças , Expressão Gênica , Humanos , Macrófagos/metabolismo , Macrófagos/virologia , Camundongos , Modelos Moleculares , Mutação , Ligação Proteica , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Receptores Imunológicos/química , Receptores Imunológicos/metabolismo , Receptores Virais/química , Receptores Virais/metabolismo , Tropismo Viral , Ligação Viral
12.
Sci Rep ; 6: 28688, 2016 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-27345289

RESUMO

Directly acting antivirals recently have become available for the treatment of hepatitis C virus (HCV) infection, but there is no prophylactic vaccine for HCV. In the present study, we took advantage of the properties of Japanese encephalitis virus (JEV) to develop antigens for use in a HCV vaccine. Notably, the surface-exposed JEV envelope protein is tolerant of inserted foreign epitopes, permitting display of novel antigens. We identified 3 positions that permitted insertion of the HCV E2 neutralization epitope recognized by HCV1 antibody. JEV subviral particles (SVP) containing HCV-neutralization epitope (SVP-E2) were purified from culture supernatant by gel chromatography. Sera from mice immunized with SVP-E2 inhibited infection by JEV and by trans-complemented HCV particles (HCVtcp) derived from multi-genotypic viruses, whereas sera from mice immunized with synthetic E2 peptides did not show any neutralizing activity. Furthermore, sera from mice immunized with SVP-E2 neutralized HCVtcp with N415K escape mutation in E2. As with the SVP-E2 epitope-displaying particles, JEV SVPs with HCV E1 epitope also elicited neutralizing antibodies against HCV. Thus, this novel platform harboring foreign epitopes on the surface of the particle may facilitate the development of a bivalent vaccine against JEV and other pathogens.


Assuntos
Vírus da Encefalite Japonesa (Espécie)/imunologia , Encefalite Japonesa , Hepacivirus/imunologia , Anticorpos Anti-Hepatite C , Hepatite C , Vacinas contra o Vírus do Herpes Simples , Vacinas contra Encefalite Japonesa , Animais , Linhagem Celular Tumoral , Vírus da Encefalite Japonesa (Espécie)/genética , Encefalite Japonesa/genética , Encefalite Japonesa/imunologia , Encefalite Japonesa/prevenção & controle , Feminino , Hepacivirus/genética , Hepatite C/genética , Hepatite C/imunologia , Hepatite C/prevenção & controle , Anticorpos Anti-Hepatite C/imunologia , Vacinas contra o Vírus do Herpes Simples/genética , Vacinas contra o Vírus do Herpes Simples/imunologia , Vacinas contra o Vírus do Herpes Simples/farmacologia , Humanos , Vacinas contra Encefalite Japonesa/genética , Vacinas contra Encefalite Japonesa/imunologia , Vacinas contra Encefalite Japonesa/farmacologia , Camundongos , Camundongos Endogâmicos BALB C
13.
Infect Genet Evol ; 41: 160-173, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27071530

RESUMO

Rotaviruses C (RVCs) circulate worldwide as an enteric pathogen in both humans and animals. Most studies of their genetic diversity focus on the VP7 and VP4 genes, but the complete genomes of 18 human RVCs have been described in independent studies. The genetic background of the Far East Asian RVCs is different than other human RVCs that were found in India and Bangladesh. Recently, a RVC detected in 2010 in South Korea had genetic background similar to the Indian-Bangladeshi RVCs. This study was undertaken to determine the whole genome of eight Japanese RVCs detected in 2005-2012, and to compare them with other human and animal global RVCs to better understand the genetic background of contemporary Far East Asian RVC. By phylogenetic analysis, the human RVCs appeared to be distinct from animal RVCs. Among human RVCs, three lineage constellations had prolonged circulation. The genetic background of the Far East Asian RVC was distinguished from Indian-Bangladeshi RVC as reported earlier. However, we found one Japanese RVC in 2012 that carried the genetic background of Indian-Bangladeshi RVC, whereas the remaining seven Japanese RVCs carried the typical genetic background of Far East Asian RVC. This is the first report of the Indian-Bangladeshi RVC in Japan. With that observation and the reassortment event of human RVCs in Hungary, our study indicates that the RVCs are spreading from one region to another.


Assuntos
Genoma Viral , Filogenia , RNA Viral/genética , Infecções por Rotavirus/epidemiologia , Rotavirus/genética , Doenças dos Suínos/epidemiologia , Animais , Proteínas do Capsídeo/genética , Bovinos , Cães , Europa Oriental/epidemiologia , Ásia Oriental/epidemiologia , Biblioteca Gênica , Variação Genética , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Rotavirus/classificação , Rotavirus/isolamento & purificação , Infecções por Rotavirus/transmissão , Infecções por Rotavirus/virologia , Suínos/virologia , Doenças dos Suínos/transmissão , Doenças dos Suínos/virologia , Proteínas não Estruturais Virais/genética
14.
J Virol ; 90(6): 3093-111, 2016 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-26739056

RESUMO

UNLABELLED: It has been proposed that the hepatitis C virus (HCV) NS4B protein triggers the membranous HCV replication compartment, but the underlying molecular mechanism is not fully understood. Here, we screened for NS4B-associated membrane proteins by tandem affinity purification and proteome analysis and identified 202 host proteins. Subsequent screening of replicon cells with small interfering RNA identified prolactin regulatory element binding (PREB) to be a novel HCV host cofactor. The interaction between PREB and NS4B was confirmed by immunoprecipitation, immunofluorescence, and proximity ligation assays. PREB colocalized with double-stranded RNA and the newly synthesized HCV RNA labeled with bromouridine triphosphate in HCV replicon cells. Furthermore, PREB shifted to detergent-resistant membranes (DRMs), where HCV replication complexes reside, in the presence of NS4B expression in Huh7 cells. However, a PREB mutant lacking the NS4B-binding region (PREBd3) could not colocalize with double-stranded RNA and did not shift to the DRM in the presence of NS4B. These results indicate that PREB locates at the HCV replication complex by interacting with NS4B. PREB silencing inhibited the formation of the membranous HCV replication compartment and increased the protease and nuclease sensitivity of HCV replicase proteins and RNA in DRMs, respectively. Collectively, these data indicate that PREB promotes HCV RNA replication by participating in the formation of the membranous replication compartment and by maintaining its proper structure by interacting with NS4B. Furthermore, PREB was induced by HCV infection in vitro and in vivo. Our findings provide new insights into HCV host cofactors. IMPORTANCE: The hepatitis C virus (HCV) protein NS4B can induce alteration of the endoplasmic reticulum and the formation of a membranous web structure, which provides a platform for the HCV replication complex. The molecular mechanism by which NS4B induces the membranous HCV replication compartment is not understood. We screened for NS4B-associated membrane proteins by tandem affinity purification and proteome analysis, followed by screening with small interfering RNA. We identified prolactin regulatory element binding (PREB) to be a novel HCV host cofactor. PREB is induced by HCV infection and recruited into the replication complex by interaction with NS4B. Recruited PREB promotes HCV RNA replication by participating in the formation of the membranous HCV replication compartment. To our knowledge, the effect of NS4B-binding protein on the formation of the membranous HCV replication compartment is newly described in this report. Our findings are expected to provide new insights into HCV host cofactors.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Hepacivirus/fisiologia , Interações Hospedeiro-Patógeno , Fatores de Transcrição/metabolismo , Proteínas não Estruturais Virais/metabolismo , Replicação Viral , Linhagem Celular , Hepatócitos/química , Hepatócitos/virologia , Humanos , Mapeamento de Interação de Proteínas/métodos , Proteômica/métodos
15.
Gerontology ; 61(2): 109-15, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25341537

RESUMO

BACKGROUND: Although fall predictions using motor ability have been well reported in elderly people, there are few reports on physical cognitive ability. OBJECTIVE: To examine the relationship of the results of motor function tests that include physical cognitive ability on the ability to predict falls and to determine which test is the most appropriate. METHODS: We studied 174 community-dwelling elderly adults (mean age 75.7 ± 5.7, 41 males and 133 females), and measured grip strength, one-leg standing time (OLS), timed up and go test (TUG), functional reach test, sit and reach test, and maximal step length (MSL). The estimation error (EE), which was defined as the difference between the predicted and actual values, was calculated in all motor ability tests. Other assessments included the number of falls in the previous year, BMI, frequency of going out, Mini-Mental State Examination score, and Falls Efficacy Scale. In the baseline study, we divided the subjects into a fall group (n = 33) and a nonfall group (n = 141) and compared motor ability and EE for the two groups. During a 1-year follow-up, the nonfall group (baseline study) was assessed for the same measurements by using the same methods. RESULTS: In the baseline study, the fall group had significantly lower values of OLS and MSL. Furthermore, the fall group significantly overestimated their OLS, TUG, and MSL. In logistic regression analysis, EE of TUG (OR = 1.27) and EE of MSL (OR = 1.08) were detected as risk factors for falls. During follow-up, 11 subjects (7.8%) experienced falls. In logistic regression analysis, TUG (OR = 1.89) and EE of MSL (OR = 1.06) were detected as significant risk factors for falls. Since EE of MSL had higher values of both the area under the receiver operating characteristic curve and the sum of sensitivity and specificity than EE of TUG, the nonfall group was divided into two groups with a cutoff value of 2 cm for EE of MSL. A significant distribution disparity in falls between the two groups was found during follow-up and showed a relative risk of 18.78 for EE of MSL. CONCLUSIONS: We suggest that EE of MSL is a potent predictor for falls among healthy elderly adults.


Assuntos
Acidentes por Quedas , Envelhecimento , Atividade Motora/fisiologia , Destreza Motora/fisiologia , Desempenho Psicomotor , Acidentes por Quedas/prevenção & controle , Acidentes por Quedas/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Envelhecimento/psicologia , Teste de Esforço/métodos , Feminino , Avaliação Geriátrica , Humanos , Vida Independente , Masculino , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Medição de Risco/métodos
16.
Biochem Biophys Res Commun ; 443(3): 808-13, 2014 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-24342612

RESUMO

Hepatitis B virus (HBV) entry has been analyzed using infection-susceptible cells, including primary human hepatocytes, primary tupaia hepatocytes, and HepaRG cells. Recently, the sodium taurocholate cotransporting polypeptide (NTCP) membrane transporter was reported as an HBV entry receptor. In this study, we established a strain of HepG2 cells engineered to overexpress the human NTCP gene (HepG2-hNTCP-C4 cells). HepG2-hNTCP-C4 cells were shown to be susceptible to infection by blood-borne and cell culture-derived HBV. HBV infection was facilitated by pretreating cells with 3% dimethyl sulfoxide permitting nearly 50% of the cells to be infected with HBV. Knockdown analysis suggested that HBV infection of HepG2-hNTCP-C4 cells was mediated by NTCP. HBV infection was blocked by an anti-HBV surface protein neutralizing antibody, by compounds known to inhibit NTCP transporter activity, and by cyclosporin A and its derivatives. The infection assay suggested that cyclosporin B was a more potent inhibitor of HBV entry than was cyclosporin A. Further chemical screening identified oxysterols, oxidized derivatives of cholesterol, as inhibitors of HBV infection. Thus, the HepG2-hNTCP-C4 cell line established in this study is a useful tool for the identification of inhibitors of HBV infection as well as for the analysis of the molecular mechanisms of HBV infection.


Assuntos
Vírus da Hepatite B/fisiologia , Transportadores de Ânions Orgânicos Dependentes de Sódio/metabolismo , Simportadores/metabolismo , Internalização do Vírus , Animais , Dimetil Sulfóxido/farmacologia , Células Hep G2 , Hepatite B/patologia , Hepatite B/virologia , Vírus da Hepatite B/efeitos dos fármacos , Humanos , Transportadores de Ânions Orgânicos Dependentes de Sódio/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Simportadores/genética , Tupaia , Internalização do Vírus/efeitos dos fármacos
17.
Clin Exp Nephrol ; 17(2): 211-7, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22948416

RESUMO

BACKGROUND: Since dyslipidemia has been shown to be an independent risk factor for the progression of chronic kidney disease (CKD), low-density lipoprotein cholesterol (LDL-C)-lowering therapy can be potentially associated with inhibition of CKD progression. The ASsessment of clinical Usefulness in CKD patients with Atorvastatin (ASUCA) trial was designed to determine whether atorvastatin has protective effects on renal function in patients with dyslipidemia and CKD. METHODS: We decided to carry out a prospective multi-center, open-labeled, randomized trial to compare the reno-protective effects between diet therapy alone and atorvastatin plus diet therapy in patients with dyslipidemia (LDL-C ≥ 140 mg/dL if not treated or LDL-C ≥ 100 mg/dL if treated with lipid-lowering drugs in subjects taking dyslipidemia-treating agents other than statins) and CKD [estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m(2)]. The primary endpoint is the change in eGFR (mL/min/1.73 m(2)) as calculated by the modified MDRD equation for Japanese after 2 years of treatment. RESULTS: Enrollment began in April 2009 and was completed in March 2011. A total of 334 patients (213 male and 121 female) were randomly assigned to either diet therapy alone or atorvastatin plus diet therapy and included in an intent-to-treat population. In the atorvastatin and control groups, the mean ages were 63.2 and 63.1 years, mean eGFRs were 55.9 and 54.0 mL/min/1.73 m(2), and median urinary albumin/creatinine ratios were 24.9 and 29.1 mg/g, respectively. CONCLUSIONS: This study distinguishes itself from similar studies by increasing statistical accuracy derived from its significantly larger sample size and longitudinal magnitude. The results of this study will help to determine whether atorvastatin has reno-protective effects in patients with dyslipidemia and CKD.


Assuntos
Dislipidemias/tratamento farmacológico , Ácidos Heptanoicos/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Pirróis/uso terapêutico , Insuficiência Renal Crônica/complicações , Adulto , Idoso , Atorvastatina , LDL-Colesterol/sangue , Interpretação Estatística de Dados , Progressão da Doença , Dislipidemias/complicações , Determinação de Ponto Final , Feminino , Taxa de Filtração Glomerular , Humanos , Japão , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Projetos de Pesquisa , Resultado do Tratamento
18.
Expert Rev Cardiovasc Ther ; 10(5): 577-83, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22651833

RESUMO

Hypertension is one of the most prevalent disorders and the largest contributor to global mortality. The aim of antihypertensive treatment is to reduce the risk of cardiovascular morbidity and mortality by lowering increased blood pressure (BP) to target levels. Despite progress in antihypertensive drug development, BP control remains suboptimal. Accumulating evidence has shown that fixed-dose combination therapy is better in terms of BP control than increasing the dose of one drug or its corresponding combination. Fixed-dose combinations of an angiotensin receptor blocker, candesartan cilexetil, and a calcium channel blocker, amlodipine besilate (candesartan/amlodipine 8/2.5 or 8/5 mg), were approved in Japan for once-daily oral administration in hypertensive patients. Recent data showed that a fixed-dose combination of candesartan and amlodipine lowered BP safely and rapidly, providing a potential opportunity to improve the rate of BP control. Further studies are needed to determine whether this will lead to improvements in long-term clinical outcomes.


Assuntos
Anlodipino/uso terapêutico , Benzimidazóis/uso terapêutico , Compostos de Bifenilo/uso terapêutico , Hipertensão/tratamento farmacológico , Tetrazóis/uso terapêutico , Administração Oral , Anlodipino/administração & dosagem , Anlodipino/efeitos adversos , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/efeitos adversos , Anti-Hipertensivos/uso terapêutico , Benzimidazóis/administração & dosagem , Benzimidazóis/efeitos adversos , Compostos de Bifenilo/administração & dosagem , Compostos de Bifenilo/efeitos adversos , Pressão Sanguínea/efeitos dos fármacos , Combinação de Medicamentos , Humanos , Hipertensão/fisiopatologia , Japão , Tetrazóis/administração & dosagem , Tetrazóis/efeitos adversos
19.
Nihon Rinsho ; 70(3): 519-27, 2012 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-22514936

RESUMO

The Candesartan Antihypertensive Survival Evaluation in Japan (CASE-J) trial was conducted to compare the effects of the angiotensin II receptor blocker (ARB) candesartan and the calcium channel blocker (CCB) amlodipine on the incidence of cardiovascular events in Japanese high-risk hypertensive patients. The CASE-J Extension (CASE-J Ex) was an observational study designed to evaluate the long-term effects of ARB candesartan and CCB amlodipine, incorporating an additional 3-year follow-up of the CASE-J trial. As in the CASE-J trial, no statistically significant difference was observed in the incidence of primary cardiovascular events, all-cause mortality, or cardiovascular death between the two groups. The superiority of candesartan over amlodipine in reducing new-onset diabetes was sustained in the three-year-long CASE-J Ex, thereby corroborating the results of the CASE-J trial.


Assuntos
Anlodipino/uso terapêutico , Antagonistas de Receptores de Angiotensina/uso terapêutico , Benzimidazóis/uso terapêutico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Hipertensão/tratamento farmacológico , Tetrazóis/uso terapêutico , Compostos de Bifenilo , Diabetes Mellitus Tipo 2/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
Diabetes Res Clin Pract ; 96(1): 68-75, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22197527

RESUMO

AIM: To determine whether renin-angiotensin system (RAS) blockade is beneficial for cardiovascular outcomes in patients with diabetes mellitus (DM) using meta-analysis. METHODS: The MEDLINE and Cochrane library databases were searched for randomized controlled trials published up to June 2010. We also reviewed reference lists from identified trials and review articles to identify any other relevant studies, and the ClinicalTrials.gov website to identify randomized controlled trials that were registered as completed but not yet published. A random-effects model was used to combine the estimates for risk ratios (RR). RESULTS: Eligible studies were randomized controlled trials (including post hoc analyses) assessing the effects of angiotensin-converting enzyme inhibitors or angiotensin-receptor blockers on cardiovascular events compared to controls in patients with DM. Nineteen clinical trials with 41,042 patients and 6039 cardiovascular events were identified. RAS blockade significantly reduced the risk of major cardiovascular events (RR 0.92, 95% confidence interval [CI] 0.84-1.00, I(2) statistic 53%) and myocardial infarction (RR 0.82, 95% CI 0.72-0.94, I(2)=55%). There were trends towards fewer strokes and lower all-cause mortality but these were not statistically significant. CONCLUSIONS: The available evidence shows that treatment with RAS blockade can routinely be considered for diabetic patients to reduce major cardiovascular events.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Humanos , Infarto do Miocárdio/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto
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