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1

Human enterovirus 71 subgenotype B3 lacks coxsackievirus A16-like neurovirulence in mice infection  

PubMed Central

Background At least three different EV-71 subgenotypes were identified from an outbreak in Malaysia in 1998. The subgenotypes C2 and B4 were associated with the severe and fatal infections, whereas the B3 virus was associated with mild to subclinical infections. The B3 virus genome sequences had ?85% similarity at the 3' end to CV-A16. This offers opportunities to examine if there are characteristic similarities and differences in virulence between CV-A16, EV-71 B3 and EV-71 B4 and to determine if the presence of the CV-A16-liked genes in EV-71 B3 would also confer the virus with a CV-A16-liked neurovirulence in mice model infection. Results Analysis of human enterovirus 71 (EV-71) subgenotype B3 genome sequences revealed that the 3D RNA polymerase and domain Z of the 3'-untranslating region RNA secondary structure had high similarity to CV-A16. Intracerebral inoculation of one-day old mice with the virus resulted in 16% of the mice showing swollen hind limbs and significantly lower weight gain in comparison to EV-71 B4-infected mice. None of the mice presented with hind leg paralysis typical in all the CV-A16 infected mice. CV-A16 genome sequences were amplified from the CV-A16-infected mice brain but no amplification was obtained from all the EV-71-inoculated mice suggesting that no replication had taken place in the suckling mice brain. Conclusion The findings presented here suggest that EV-71 B3 viruses had CV-A16-liked non-structural gene features at the 3'-end of the genome. Their presence could have affected virulence by affecting the mice general health but was insufficient to confer the EV-71 B3 virus a CV-A16-liked neurovirulence in mice model infection. PMID:16122396

Chan, Yoke-Fun; AbuBakar, Sazaly

2005-01-01

2

Antiviral activity of ginsenosides against coxsackievirus B3, enterovirus 71, and human rhinovirus 3  

PubMed Central

Background Ginsenosides are the major components responsible for the biochemical and pharmacological actions of ginseng, and have been shown to have various biological activities. In this study, we investigated the antiviral activities of seven ginsenosides [protopanaxatriol (PT) type: Re, Rf, and Rg2; protopanaxadiol (PD) type: Rb1, Rb2, Rc, and Rd)] against coxsackievirus B3 (CVB3), enterovirus 71 (EV71), and human rhinovirus 3 (HRV3). Methods Assays of antiviral activity and cytotoxicity were evaluated by the sulforhodamine B method using the cytopathic effect (CPE) reduction assay. Results The antiviral assays demonstrated that, of the seven ginsenosides, the PT-type ginsenosides (Re, Rf, and Rg2) possess significant antiviral activities against CVB3 and HRV3 at a concentration of 100 ?g/mL. Among the PT-type ginsenosides, only ginsenoside Rg2 showed significant anti-EV71 activity with no cytotoxicity to cells at 100 ?g/mL. The PD-type ginsenosides (Rb1, Rb2, Rc, and Rd), by contrast, did not show any significant antiviral activity against CVB3, EV71, and HRV3, and exhibited cytotoxic effects to virus-infected cells. Notably, the antiviral efficacies of PT-type ginsenosides were comparable to those of ribavirin, a commonly used antiviral drug. Conclusion Collectively, our findings suggest that the ginsenosides Re, Rf, and Rg2 have the potential to be effective in the treatment of CVB3, EV71, and HRV3 infection. PMID:25378991

Song, Jae-Hyoung; Choi, Hwa-Jung; Song, Hyuk-Hwan; Hong, Eun-Hye; Lee, Bo-Ra; Oh, Sei-Ryang; Choi, Kwangman; Yeo, Sang-Gu; Lee, Yong-Pyo; Cho, Sungchan; Ko, Hyun-Jeong

2014-01-01

3

Experimental human rhinovirus and enterovirus interspecies recombination.  

PubMed

Human rhinoviruses (HRVs) and enteroviruses (HEVs), two important human pathogens, are non-enveloped, positive-sense RNA viruses of the genus Enterovirus within the family Picornaviridae. Intraspecies recombination is known as a driving force for enterovirus and, to a lesser extent, rhinovirus evolution. Interspecies recombination is much less frequent among circulating strains, and supporting evidence for such recombination is limited to ancestral events, as shown by recent phylogenetic analyses reporting ancient HRV-A/HRV-C, HEV-A/HEV-C and HEV-A/HEV-D recombination mainly at the 5'-untranslated region (5' UTR)-polyprotein junction. In this study, chimeric genomes were artificially generated using the 5' UTR from two different clinical HRV-C strains (HRV-Ca and HRV-Cc), an HRV-B strain (HRV-B37) and an HEV-A strain (HEV-A71), and the remaining part of the genome from an HRV-A strain (HRV-A16). Whilst the chimeric viruses were easily propagated in cell culture, the wild-type HRV-A16 retained a replication advantage, both individually and in competition experiments. Assessment of protein synthesis ability did not show a correlation between translation and replication efficiencies. These results reflect the interchangeability of the 5' UTR, including its functional RNA structural elements implicated in both genome translation and replication among different enterovirus species. The 5' UTR-polyprotein junction therefore represents a theoretic interspecies recombination breakpoint. This recombination potential is probably restricted by the need for co-infection opportunities and the requirement for the progeny chimera to outcompete the parental genomes' fitness, explaining the rare occurrence of such events in vivo. PMID:21940413

Schibler, Manuel; Gerlach, Daniel; Martinez, Yannick; Belle, Sandra Van; Turin, Lara; Kaiser, Laurent; Tapparel, Caroline

2012-01-01

4

Transmission of Human Enterovirus 85 Recombinants Containing New Unknown Serotype HEV-B Donor Sequences in Xinjiang Uighur Autonomous Region, China  

PubMed Central

Background Human enterovirus 85 (HEV85), whose prototype strain (Strain BAN00-10353/BAN/2000) was isolated in Bangladesh in 2000, is a recently identified serotype within the human enterovirus B (HEV-B) species. At present, only one nucleotide sequence of HEV85 (the complete genome sequence of the prototype strain) is available in the GenBank database. Principal Findings In this study, we report the genetic characteristics of 33 HEV85 isolates that circulated in the Xinjiang Uighur autonomous region of China in 2011. Sequence analysis revealed that all these Chinese HEV85 isolates belong to 2 transmission chains, and intertypic recombination was found with the new unknown serotype HEV-B donor sequences. Two HEV85 isolates recovered from a patient presenting acute flaccid paralysis and one of his contacts were temperature-insensitive strains, and some nucleotide substitutions in the non-coding regions and in the 2C or 3D coding regions may have affected the temperature sensitivity of HEV85 strains. Conclusions The Chinese HEV85 recombinant described in this study trapped a new unknown serotype HEV-B donor sequence, indicating that new unknown HEV-B serotypes exist or circulate in Xinjiang of China. Our study also indicated that HEV85 is a prevalent and common enterovirus serotype in Xinjiang. PMID:23383202

Tian, Huifang; Huang, Guohong; Cui, Hui; Li, Xiaolei; Yan, Dongmei; Zhu, Zhen; Li, Jing; Zheng, Peng; Jiang, Huafang; Zhang, Bo; Tan, Xiaojuan; Zhu, Hui; An, Hongqiu; Xu, Wenbo

2013-01-01

5

Crystal Structure of Human Enterovirus 71  

SciTech Connect

Enterovirus 71 is a picornavirus associated with fatal neurological illness in infants and young children. Here, we report the crystal structure of enterovirus 71 and show that, unlike in other enteroviruses, the 'pocket factor,' a small molecule that stabilizes the virus, is partly exposed on the floor of the 'canyon.' Thus, the structure of antiviral compounds may require a hydrophilic head group designed to interact with residues at the entrance of the pocket.

Plevka, Pavel; Perera, Rushika; Cardosa, Jane; Kuhn, Richard J.; Rossmann, Michael G. (Purdue); (Sentinext)

2013-04-08

6

Crystal structure of human enterovirus 71.  

PubMed

Enterovirus 71 is a picornavirus associated with fatal neurological illness in infants and young children. Here, we report the crystal structure of enterovirus 71 and show that, unlike in other enteroviruses, the "pocket factor," a small molecule that stabilizes the virus, is partly exposed on the floor of the "canyon." Thus, the structure of antiviral compounds may require a hydrophilic head group designed to interact with residues at the entrance of the pocket. PMID:22383808

Plevka, Pavel; Perera, Rushika; Cardosa, Jane; Kuhn, Richard J; Rossmann, Michael G

2012-06-01

7

Prevalence of human enteroviruses among apparently healthy nursery school children in Accra  

PubMed Central

Introduction Human enteroviruses are common in children causing asymptomatic infections ranging from mild to severe illnesses. In Ghana, information on the prevalence of non-polio enterovirus causing acute flaccid paralysis is available but data on surveillance of these viruses in school children is scanty. Here, the prevalence of human enteroviruses among apparently healthy children in selected school in Accra was studied. Methods Stool samples from 273 apparently healthy children less than eight years of age in 9 selected nursery schools were collected between December 2010 and March 2011and processed for human enteroviruses on L20B, RD and Hep-2 cell lines. Positive Isolates were characterized by microneutralisation assay with antisera pools from RIVM, the Netherlands according to standard methods recommended by WHO. Results Of the 273 samples processed, 66 (24.2%) non-polio enteroviruses were isolated. More growth was seen on Hep-2C (46%) only than RD (18%) only and on both cell lines (34%). No growth was seen on L20B even after blind passage. Excretion of non-polio enteroviruses was found in all the schools with majority in BD school. Serotyping of the isolates yielded predominantly Coxsackie B viruses followed by echoviruses 13 and 7. More than half of the isolates could not be typed by the antisera pools. Conclusion The study detected 13 different serotypes of non-polio enteroviruses in circulation but no poliovirus was found. BD school was found to have the highest prevalence of NPEV. Complete identification through molecular methods is essential to establish the full range of NPEVs in circulation in these schools. PMID:25400833

Attoh, Juliana; Obodai, Evangeline; Adiku, Theophilus; Odoom, John Kofi

2014-01-01

8

Human Rhinovirus 87 and Enterovirus 68 Represent a Unique Serotype with Rhinovirus and Enterovirus Features  

PubMed Central

It has recently been reported that all but one of the 102 known serotypes of the genus Rhinovirus segregate into two genetic clusters (C. Savolainen, S. Blomqvist, M. N. Mulders, and T. Hovi, J. Gen. Virol. 83:333-340, 2002). The only exception is human rhinovirus 87 (HRV87). Here we demonstrate that HRV87 is genetically and antigenically highly similar to enterovirus 68 (EV68) and is related to EV70, the other member of human enterovirus group D. The partial nucleotide sequences of the 5? untranslated region, capsid regions VP4/VP2 and VP1, and the 3D RNA polymerase gene of the HRV87 prototype strain F02-3607 Corn showed 97.3, 97.8, 95.2, and 95.9% identity to the corresponding regions of EV68 prototype strain Fermon. The amino acid identities were 100 and 98.1% for the products of the two capsid regions and 97.9% for 3D RNA polymerase. Antigenic cross-reaction between HRV87 and EV68 was indicated by microneutralization with monotypic antisera. Phylogenetic analysis showed definite clustering of HRV87 and EV68 with EV70 for all sequences examined. Both HRV87 and EV68 were shown to be acid sensitive by two different assays, while EV70 was acid resistant, which is typical of enteroviruses. The cytopathic effect induced by HRV87 or EV68 was inhibited by monoclonal antibodies to the decay-accelerating factor known to be the receptor of EV70. We conclude that HRV87 and EV68 are strains of the same picornavirus serotype presenting features of both rhinoviruses and enteroviruses. PMID:12409401

Blomqvist, Soile; Savolainen, Carita; Råman, Laura; Roivainen, Merja; Hovi, Tapani

2002-01-01

9

Susceptibility of the VERO line of African green monkey kidney cells to human enteroviruses  

PubMed Central

The relative susceptibility of VERO cells and primary rhesus monkey kidney cells to 47 prototype strains of human enteroviruses is described. Of these strains, types 4, 14, 16, 17, 18, 21, 31 and 34 and Coxsackie virus A 9 failed to cause CPE in the VERO cells whilst only one, echovirus type 34, failed to cause CPE in the monkey kidney cells. A comparison is given of the efficiency of the two cell cultures for enterovirus isolation from clinical material. Results show that VERO cells are as useful as primary monkey kidney for the isolation of Coxsackie B viruses but less satisfactory for isolating echoviruses. They are satisfactory for the isolation of single types of poliovirus and appear to be more satisfactory than primary monkey kidney cells for the isolation of mixtures of polioviruses. The identification of enteroviruses by neutralization tests in VERO cells is successful. PMID:4361500

Davis, Patricia M.; Phillpotts, R. J.

1974-01-01

10

Complete genome analysis of porcine enterovirus B isolated in Korea.  

PubMed

The complete genome sequence of porcine enterovirus B (PEV-B) from a Korean isolate was analyzed. The genome size was 7,393 bp. Previously, full genome sequences of PEV-B had been reported from the United Kingdom, Hungary, and China. The Korean PEV-B isolate presented polyprotein gene nucleotide sequence similarities of 77.9, 73.7, 78.9, and 80.3%, respectively, to PEV-B UKG/410/73, LP54, PEV15, and Chinese strains (Ch-ah-f1). PMID:22923807

Moon, Hyoung-Joon; Song, DaeSub; Seon, Bo Hyeon; Kim, Hye-Kwon; Park, Seong-Jun; An, Dong-Jun; Kim, Jong-Man; Kang, Bo-Kyu; Park, Bong-Kyun

2012-09-01

11

Human Enterovirus 109: a Novel Interspecies Recombinant Enterovirus Isolated from a Case of Acute Pediatric Respiratory Illness in Nicaragua? †  

PubMed Central

Enteroviruses (Picornaviridae family) are a common cause of human illness worldwide and are associated with diverse clinical syndromes, including asymptomatic infection, respiratory illness, gastroenteritis, and meningitis. In this study, we report the identification and complete genome sequence of a novel enterovirus isolated from a case of acute respiratory illness in a Nicaraguan child. Unbiased deep sequencing of nucleic acids from a nose and throat swab sample enabled rapid recovery of the full-genome sequence. Phylogenetic analysis revealed that human enterovirus 109 (EV109) is most closely related to serotypes of human enterovirus species C (HEV-C) in all genomic regions except the 5? untranslated region (5? UTR). Bootstrap analysis indicates that the 5? UTR of EV109 is likely the product of an interspecies recombination event between ancestral members of the HEV-A and HEV-C groups. Overall, the EV109 coding region shares 67 to 72% nucleotide sequence identity with its nearest relatives. EV109 isolates were detected in 5/310 (1.6%) of nose and throat swab samples collected from children in a pediatric cohort study of influenza-like illness in Managua, Nicaragua, between June 2007 and June 2008. Further experimentation is required to more fully characterize the pathogenic role, disease associations, and global distribution of EV109. PMID:20592079

Yozwiak, Nathan L.; Skewes-Cox, Peter; Gordon, Aubree; Saborio, Saira; Kuan, Guillermina; Balmaseda, Angel; Ganem, Don; Harris, Eva; DeRisi, Joseph L.

2010-01-01

12

Deferoxamine compensates for decreases in B cell counts and reduces mortality in enterovirus 71-infected mice.  

PubMed

Enterovirus 71 is one of the major causative agents of hand, foot and mouth disease in children under six years of age. No vaccine or antiviral therapy is currently available. In this work, we found that the number of B cells was reduced in enterovirus 71-infected mice. Deferoxamine, a marine microbial natural product, compensated for the decreased levels of B cells caused by enterovirus 71 infection. The neutralizing antibody titer was also improved after deferoxamine treatment. Furthermore, deferoxamine relieved symptoms and reduced mortality and muscle damage caused by enterovirus 71 infection. This work suggested that deferoxamine has the potential for further development as a B cell-immunomodulator against enterovirus 71. PMID:25003792

Yang, Yajun; Ma, Jing; Xiu, Jinghui; Bai, Lin; Guan, Feifei; Zhang, Li; Liu, Jiangning; Zhang, Lianfeng

2014-07-01

13

Complete Genome Characterization of a Novel Enterovirus Type EV-B106 Isolated in China, 2012  

PubMed Central

Human enterovirus B106 (EV-B106) is a recently identified member of enterovirus species B. In this study, we report the complete genomic characterization of an EV-B106 strain (148/YN/CHN/12) isolated from an acute flaccid paralysis patient in Yunnan Province, China. The new strain had 79.2–81.3% nucleotide and 89.1–94.8% amino acid similarity in the VP1 region with the other two EV-B106 strains from Bolivia and Pakistan. When compared with other EV serotypes, it had the highest (73.3%) VP1 nucleotide similarity with the EV-B77 prototype strain CF496-99. However, when aligned with all EV-B106 and EV-B77 sequences available from the GenBank database, two major frame shifts were observed in the VP1 coding region, which resulted in substantial (20.5%) VP1 amino acid divergence between the two serotypes. Phylogenetic analysis and similarity plot analysis revealed multiple recombination events in the genome of this strain. This is the first report of the complete genome of EV-B106. PMID:24584702

Tang, Jingjing; Tao, Zexin; Ding, Zhengrong; Zhang, Yong; Zhang, Jie; Tian, Bingjun; Zhao, Zhixian; Zhang, Lifen; Xu, Wenbo

2014-01-01

14

Human Enterovirus 71 Uncoating Captured at Atomic Resolution  

PubMed Central

ABSTRACT Human enterovirus 71 (EV71) is the major causative agent of severe hand-foot-and-mouth diseases (HFMD) in young children, and structural characterization of EV71 during its life cycle can aid in the development of therapeutics against HFMD. Here, we present the atomic structures of the full virion and an uncoating intermediate of a clinical EV71 C4 strain to illustrate the structural changes in the full virion that lead to the formation of the uncoating intermediate prepared for RNA release. Although the VP1 N-terminal regions observed to penetrate through the junction channel at the quasi-3-fold axis in the uncoating intermediate of coxsackievirus A16 were not observed in the EV71 uncoating intermediate, drastic conformational changes occur in this region, as has been observed in all capsid proteins. Additionally, the RNA genome interacts with the N-terminal extensions of VP1 and residues 32 to 36 of VP3, both of which are situated at the bottom of the junction. These observations highlight the importance of the junction for genome release. Furthermore, EV71 uncoating is associated with apparent rearrangements and expansion around the 2- and 5-fold axes without obvious changes around the 3-fold axes. Therefore, these structures enabled the identification of hot spots for capsid rearrangements, which led to the hypothesis that the protomer interface near the junction and the 2-fold axis permits the opening of large channels for the exit of polypeptides and viral RNA, which is an uncoating mechanism that is likely conserved in enteroviruses. IMPORTANCE Human enterovirus 71 (EV71) is the major causative agent of severe hand-foot-and-mouth diseases (HFMD) in young children. EV71 contains an RNA genome protected by an icosahedral capsid shell. Uncoating is essential in EV71 life cycle, which is characterized by conformational changes in the capsid to facilitate RNA release into host cell. Here we present the atomic structures of the full virion and an uncoating intermediate of a clinical C4 strain of EV71. Structural analysis revealed drastic conformational changes associated with uncoating in all the capsid proteins near the junction at the quasi-3-fold axis and protein-RNA interactions at the bottom of the junction in the uncoating intermediate. Significant capsid rearrangements also occur at the icosahedral 2- and 5-fold axes but not at the 3-fold axis. Taking the results together, we hypothesize that the junction and nearby areas are hot spots for capsid breaches for the exit of polypeptides and viral RNA during uncoating. PMID:24352461

Lyu, Ke; Ding, Jie; Han, Jian-Feng; Zhang, Yu; Wu, Xiao-Yan; He, Ya-Ling; Qin, Cheng-Feng

2014-01-01

15

Virucidal activity of Virkon S on human enterovirus.  

PubMed

The efficacy of Virkon S, a commercial disinfectant as a virucidal spray against human enterovirus 71 (HEV71), the causative agent of the fatal form of hand, foot and mouth disease was examined. At least one log10 reduction of HEV71 titer was achieved when one spray of Virkon (1% or 2%) with ten minutes of contact time was applied. The infectivity was completely lost when four sprays of 1% or 2% Virkon were applied, suggesting that at least four sprays of 1% Virkon to the surface bound HEV71 was necessary to completely inactivate the virus. These findings suggest that Virkon S at the proper concentration is suitable to be used as an effective and easy to use disinfectant against HEV71. PMID:16114171

Chan, Y F; Abu Bakar, S

2005-06-01

16

Molecular epidemiology of enterovirus B77 isolated from non polio acute flaccid paralytic patients in Pakistan during 2013.  

PubMed

Human enteroviruses are associated with various clinical syndromes and severe neurological disorders. The aim of this study was to determine the molecular epidemiology of non polio enteroviruses and their correlation with acute flaccid paralysis (AFP) patients living in Khyber Pakhtunkhwa (KP) and Federally Administered Tribal Areas (FATA) of Pakistan. The stool samples collected from these patients were used for isolation of non polio enteroviruses (NPEVs). Out of 38 samples, 29 (76.3%) were successfully typed by microneutralization assay into eleven serotypes including echovirus (E)-3 (5.3%), E-7 (2.6%), E-11 (13.2%), E-12 (7.9%), E-13 (10.5%), E-20 (7.9%), E-27 (5.3%), E-29 (10.5%), E-30 (7.9%), E-33 (2.6%), coxsackievirus (CV) B5 (2.6%) and nine isolates (23.7%) remained untyped which were confirmed as NPEVs by real time RT-PCR. Complete VP1 genetic sequencing data characterized untypeable isolates into enterovirus B77 (EV-B77). Moreover, molecular phylogenetic analysis classified these viruses into two new genotypes having high genetic diversity (at least 17.7%) with prototype. This study provides valuable information on extensive genetic diversity of EV-B77 genotypes. Although, its association with neurological disorder has not yet been known but isolation of nine EV-B77 viruses from AFP cases highlights the fact that they may have a contributing role in the etiology of AFP. In addition, it is needed to establish enterovirus surveillance system and laboratory diagnostic facilities for early detection of NPEVs that may cause poliomyelitis like paralysis especially in the situation when we are at the verge of polio eradication. PMID:25433133

Angez, Mehar; Shaukat, Shahzad; Zahra, Rabaab; Khurshid, Adnan; Sharif, Salmaan; Alam, Muhammad Masroor; Zaidi, Syed Sohail Zahoor

2015-01-01

17

Neutralizing antibodies can initiate genome release from human enterovirus 71.  

PubMed

Antibodies were prepared by immunizing mice with empty, immature particles of human enterovirus 71 (EV71), a picornavirus that causes severe neurological disease in young children. The capsid structure of these empty particles is different from that of the mature virus and is similar to "A" particles encountered when picornaviruses recognize a potential host cell before genome release. The monoclonal antibody E18, generated by this immunization, induced a conformational change when incubated at temperatures between 4 °C and 37 °C with mature virus, transforming infectious virions into A particles. The resultant loss of genome that was observed by cryo-EM and a fluorescent SYBR Green dye assay inactivated the virus, establishing the mechanism by which the virus is inactivated and demonstrating that the E18 antibody has potential as an anti-EV71 therapy. The antibody-mediated virus neutralization by the induction of genome release has not been previously demonstrated. Furthermore, the present results indicate that antibodies with genome-release activity could also be produced for other picornaviruses by immunization with immature particles. PMID:24469789

Plevka, Pavel; Lim, Pei-Yin; Perera, Rushika; Cardosa, Jane; Suksatu, Ampa; Kuhn, Richard J; Rossmann, Michael G

2014-02-11

18

Use of the 5' untranslated region and VP1 region to examine the molecular diversity in enterovirus B species.  

PubMed

Human enteroviruses evolve quickly. The 5' untranslated region (UTR) is fundamentally important for efficient viral replication and for virulence; the VP1 region correlates well with antigenic typing by neutralization, and can be used for virus identification and evolutionary studies. In order to investigate the molecular diversity in EV-B species, the 5' UTR and VP1 regions were analysed for 208 clinical isolates from a single public-health laboratory (serving New South Wales, Australia), representing 28 EV-B types. Sequences were compared with the 5' UTR and VP1 regions of 98 strains available in GenBank, representing the same 28 types. The genetic relationships were analysed using two types of software (mega and BioNumerics). The sequence analyses of the 5' UTR and VP1 regions of 306 EV-B strains demonstrated that: (i) comparing the two regions gives strong evidence of epidemiological linkage of strains in some serotypes; (ii) the intraserotypic genetic variation within each gene reveals that they evolve distinctly largely due to their different functions; and (iii) mutation and possible recombination in the two regions play significant roles in the molecular diversity of EV-B. Understanding the tempo and pattern of molecular diversity and evolution is of great importance in the pathogenesis of EV-B enteroviruses, information which will assist in disease prevention and control. PMID:25038138

Zhou, Fei; Wang, Qinning; Sintchenko, Vitali; Gilbert, Gwendolyn L; O'Sullivan, Matthew V N; Iredell, Jonathan R; Dwyer, Dominic E

2014-10-01

19

Enterovirus infection in human pancreatic islet cells, islet tropism in vivo and receptor involvement in cultured islet beta cells  

Microsoft Academic Search

Aims\\/hypothesis  It is thought that enterovirus infections cause beta-cell damage and contribute to the development of Type 1 diabetes by replicating in the pancreatic islets. We sought evidence for this through autopsy studies and by investigating known enterovirus receptors in cultured human islets.Methods  Autopsy pancreases from 12 newborn infants who died of fulminant coxsackievirus infections and from 65 Type 1 diabetic patients

P. Ylipaasto; K. Klingel; A. M. Lindberg; T. Otonkoski; R. Kandolf; T. Hovi; M. Roivainen

2004-01-01

20

Phylogenetic evidence for multiple intertypic recombinations in enterovirus B81 strains isolated in Tibet, China  

PubMed Central

Enterovirus B81 (EV-B81) is a newly identified serotype within the species enterovirus B (EV-B). To date, only eight nucleotide sequences of EV-B81 have been published and only one full-length genome sequence (the prototype strain) has been made available in the GenBank database. Here, we report the full-length genome sequences of two EV-B81 strains isolated in the Tibet Autonomous Region of China during acute flaccid paralysis surveillance activities, and we also conducted an antibody seroprevalence study in two prefectures of Tibet. The sequence comparison and phylogenetic dendrogram analysis revealed high variability among the global EV-B81 strains and frequent intertypic recombination in the non-structural protein region of EV-B serotypes, suggesting high genetic diversity of EV-B81. However, low positive rates and low titers of neutralizing antibodies against EV-B81 were detected. Nearly 68% of children under the age of five had no neutralizing antibodies against EV-B81. Hence, the extent of transmission and the exposure of the population to this EV type are very limited. Although little is known about the biological and pathogenic properties of EV-B81 because of few research in this field owing to the limited number of isolates, our study provides basic information for further studies of EV-B81. PMID:25112835

Hu, Lan; Zhang, Yong; Hong, Mei; Zhu, Shuangli; Yan, Dongmei; Wang, Dongyan; Li, Xiaolei; Zhu, Zhen; Tsewang; Xu, Wenbo

2014-01-01

21

Environmental Surveillance of Human Enteroviruses in Shandong Province, China, 2008 to 2012: Serotypes, Temporal Fluctuation, and Molecular Epidemiology  

PubMed Central

Environmental surveillance is an effective approach in investigating the circulation of polioviruses (PVs) and other human enteroviruses (EVs) in the population. The present report describes the results of environmental surveillance conducted in Shandong Province, China, from 2008 to 2012. A total of 129 sewage samples were collected, and 168 PVs and 1,007 nonpolio enteroviruses (NPEVs) were isolated. VP1 sequencing and typing were performed on all isolates. All PV strains were Sabin-like, with the numbers of VP1 substitutions ranging from 0 to 7. The NPEVs belonged to 19 serotypes, and echovirus 6 (E6), E11, coxsackievirus B3 (CVB3), E3, E12, and E7 were the six main serotypes, which accounted for 18.3%, 14.8%, 14.5%, 12.9%, 9.0%, and 5.7% of NPEVs isolated, respectively. Typical summer-fall peaks of NPEV were observed in the monthly distribution of isolation, and an epidemic pattern of annual circulation was revealed for the common serotypes. Phylogenetic analysis was performed on environmental CVB3 and E3 strains with global reference strains and local strains from aseptic meningitis patients. Shandong strains formed distinct clusters, and a close relationship was observed between local environmental and clinical strains. As an EV-specific case surveillance system is absent in China and many other countries, continuous environmental surveillance should be encouraged to investigate the temporal circulation and phylogeny of EVs in the population. PMID:24837389

Wang, Haiyan; Tao, Zexin; Li, Yan; Lin, Xiaojuan; Yoshida, Hiromu; Song, Lizhi; Zhang, Yong; Wang, Suting; Cui, Ning; Xu, Wenbo

2014-01-01

22

Chebulagic Acid, a Hydrolyzable Tannin, Exhibited Antiviral Activity in Vitro and in Vivo against Human Enterovirus 71  

PubMed Central

Human enterovirus 71 is one of the major causative agents of hand, foot and mouth disease in children under six years of age. Presently, no vaccines or antiviral drugs have been clinically available to employ against EV71. In this study, we demonstrate that treatment with chebulagic acid reduced the viral cytopathic effect on rhabdomyosarcoma cells with an IC50 of 12.5 ?g/mL. The utilization of the chebulagic acid treatment on mice challenged with a lethal dose of enterovirus 71 was able to efficiently reduce mortality and relieve clinical symptoms through the inhibition of viral replication. Chebulagic acid may represent a potential therapeutic agent to control infections to enterovirus 71. PMID:23644889

Yang, Yajun; Xiu, Jinghui; Liu, Jiangning; Zhang, Li; Li, Xiaoying; Xu, Yanfeng; Qin, Chuan; Zhang, Lianfeng

2013-01-01

23

Recombination in Circulating Enteroviruses  

PubMed Central

Recombination is a well-known phenomenon for enteroviruses. However, the actual extent of recombination in circulating nonpoliovirus enteroviruses is not known. We have analyzed the phylogenetic relationships in four genome regions, VP1, 2A, 3D, and the 5? nontranslated region (NTR), of 40 enterovirus B strains (coxsackie B viruses and echoviruses) representing 11 serotypes and isolated in 1981 to 2002 in the former Soviet Union states. In the VP1 region, strains of the same serotype expectedly grouped with their prototype strain. However, as early as the 2A region, phylogenetic grouping differed significantly from that in the VP1 region and indicated recombination within the 2A region. Moreover, in the 5? NTR and 3D region, only 1 strain of 40 grouped with its prototype strain. Instead, we observed a major group in both the 5? NTR and the 3D region that united most (in the 5? NTR) or all (in the 3D region) of the strains studied, regardless of the serotype. Subdivision within that major group in the 3D region correlated with the time of virus isolation but not with the serotype. Therefore, we conclude that a majority, if not all, circulating enterovirus B strains are recombinants relative to the prototype strains, isolated mostly in the 1950s. Moreover, the ubiquitous recombination has allowed different regions of the enterovirus genome to evolve independently. Thus, a novel model of enterovirus genetics is proposed: the enterovirus genome is a stable symbiosis of genes, and enterovirus species consist of a finite set of capsid genes responsible for different serotypes and a continuum of nonstructural protein genes that seem to evolve in a relatively independent manner. PMID:12970427

Lukashev, Alexander N.; Lashkevich, Vasilii A.; Ivanova, Olga E.; Koroleva, Galina A.; Hinkkanen, Ari E.; Ilonen, Jorma

2003-01-01

24

Complete Genome Sequence of Human Enterovirus Strain 71 (EV71/Taipei/3118/2011), Isolated from a Patient in Taiwan  

PubMed Central

This full-length genome sequence of human enterovirus strain 71 (EV71/Taipei/3118/2011) was isolated from a clinical patient in Taiwan in 2011. According to the phylogenetic analysis, the complete genome sequence in this study is part of the subgenotype C4. PMID:25573934

Lin, Chia-Pei; Liu, Jiung-Liang; Chen, Lung-Yuan; Liu, Yi-Chao; Wang, Hsiu-Chi; Lin, Shih-Jie; Chen, Pin-Chun; Wang, Kun-Teng; Huang, Chih-Hung; Yang, Yi-Chan; Cheng, Hwei-Fang; Shih, Daniel Yang-Chih

2015-01-01

25

Evolutionary Genetics of Human Enterovirus 71: Origin, Population Dynamics, Natural Selection, and Seasonal Periodicity of the VP1 Gene? †  

PubMed Central

Human enterovirus 71 (EV-71) is one of the major etiologic causes of hand, foot, and mouth disease (HFMD) among young children worldwide, with fatal instances of neurological complications becoming increasingly common. Global VP1 capsid sequences (n = 628) sampled over 4 decades were collected and subjected to comprehensive evolutionary analysis using a suite of phylogenetic and population genetic methods. We estimated that the common ancestor of human EV-71 likely emerged around 1941 (95% confidence interval [CI], 1929 to 1952), subsequently diverging into three genogroups: B, C, and the now extinct genogroup A. Genealogical analysis revealed that diverse lineages of genogroup B and C (subgenogroups B1 to B5 and C1 to C5) have each circulated cryptically in the human population for up to 5 years before causing large HFMD outbreaks, indicating the quiescent persistence of EV-71 in human populations. Estimated phylogenies showed a complex pattern of spatial structure within well-sampled subgenogroups, suggesting endemicity with occasional lineage migration among locations, such that past HFMD epidemics are unlikely to be linked to continuous transmission of a single strain of virus. In addition, rises in genetic diversity are correlated with the onset of epidemics, driven in part by the emergence of novel EV-71 subgenogroups. Using subgenogroup C1 as a model, we observe temporal strain replacement through time, and we investigate the evidence for positive selection at VP1 immunogenic sites. We discuss the consequences of the evolutionary dynamics of EV-71 for vaccine design and compare its phylodynamic behavior with that of influenza virus. PMID:20089660

Tee, Kok Keng; Lam, Tommy Tsan-Yuk; Chan, Yoke Fun; Bible, Jon M.; Kamarulzaman, Adeeba; Tong, C. Y. William; Takebe, Yutaka; Pybus, Oliver G.

2010-01-01

26

Seroepidemiology of human enterovirus71 and coxsackievirusA16 among children in Guangdong province, China  

PubMed Central

Background Hand, foot and mouth disease (HFMD) is a common pediatric illness. Mainly induced by the Enterovirus 71 and Coxsackievirus A 16 infections, the frequently occurred HFMD outbreaks have become a serious public health problem in Southeast Asia. Currently,only a few studies have investigated the human immunity to HFMD in China. In this study, we conducted a cohort study in Guangdong province, China. Methods Stored serum samples from children less than 10 years old were analyzed. The levels of EV71 and CA16 specific antibodies before, during and shortly after the 2008 large outbreak of HFMD were evaluated by the microneutralization test. The geometric mean titer (GMT) was calculated and compared. Statistical significance was taken as P?

2013-01-01

27

Protease 2A induces stress granule formation during coxsackievirus B3 and enterovirus 71 infections.  

PubMed

BackgroundStress granules (SGs) are granular aggregates in the cytoplasm that are formed under a variety of stress situations including viral infection. Previous studies indicate that poliovirus, a member of Picornaviridae, can induce SG formation. However, the exact mechanism by which the picornaviruses induce SG formation is unknown.MethodThe localization of SG markers in cells infected with coxsackievirus B3 (CVB3) or enterovirus 71 (EV71) and in cells expressing each viral protein was determined via immunofluorescence assays or plasmid transfection. Eight plasmids expressing mutants of the 2A protease (2Apro) of CVB3 were generated using a site-directed mutagenesis strategy. The cleavage efficiencies of eIF4G by CVB3 2Apro, and its mutants were determined via western blotting assays.ResultsIn this study, we found that CVB3 infection induced SG formation, as evidenced by the co-localization of some accepted SG markers in viral infection-induced granules. Furthermore, we identified that 2Apro of CVB3 was the key viral component that triggered SG formation. A 2Apro mutant with the G122E mutation, which exhibited very low cleavage efficiency toward eIF4G, significantly attenuated its capacity for SG induction, indicating that the protease activity was required for 2Apro to initiate SG formation. Finally, we observed that SGs also formed in EV71-infected cells. Expression of EV71 2Apro alone was also sufficient to cause SG formation.ConclusionBoth CVB3 and EV71 infections can induce SG formation, and 2Apro plays a crucial role in the induction of SG formation during these infections. This finding may help us to better understand how picornaviruses initiate the SG response. PMID:25410318

Wu, Shuo; Wang, Yan; Lin, Lexun; Si, Xiaoning; Wang, Tianying; Zhong, Xiaoyan; Tong, Lei; Luan, Ying; Chen, Yang; Li, Xiaoyu; Zhang, Fengmin; Zhao, Wenran; Zhong, Zhaohua

2014-11-20

28

Recombinant tandem multi-linear neutralizing epitopes of human enterovirus 71 elicited protective immunity in mice  

PubMed Central

Background Human Enterovirus 71 (EV71) has emerged as the leading cause of viral encephalitis in children, especially in the Asia-Pacific regions. EV71 vaccine development is of high priority at present, and neutralization antibodies have been documented to play critical roles during in vitro and in vivo protection against EV71 infection. Results In this study, a novel strategy to produce EV71 vaccine candidate based on recombinant multiple tandem linear neutralizing epitopes (mTLNE) was proposed. The three well identified EV71 linear neutralizing epitopes in capsid proteins, VP1-SP55, VP1-SP70 and VP2-SP28, were sequentially linked by a Gly-Ser linker ((G4S)3), and expressed in E.coli in fusion with the Trx and His tag at either terminal. The recombinant protein mTLNE was soluble and could be purified by standard affinity chromatography. Following three dosage of immunization in adult mice, EV71-specific IgG and neutralization antibodies were readily induced by recombinant mTLNE. IgG subtyping demonstrated that lgG1 antibodies dominated the mTLNE-induced humoral immune response. Especially, cytokine profiling in spleen cells from the mTLNE-immunized mice revealed high production of IL-4 and IL-6. Finally, in vivo challenge experiments showed that passive transfer with anti-mTLNE sera conferred full protection against lethal EV71 challenge in neonatal mice. Conclusion Our results demonstrated that this rational designed recombinant mTLNE might have the potential to be further developed as an EV71 vaccine in the future. PMID:24885030

2014-01-01

29

Characterization of Enteroviruses from non-human primates in cameroon revealed virus types widespread in humans along with candidate new types and species.  

PubMed

Enteroviruses (EVs) infecting African Non-Human Primates (NHP) are still poorly documented. This study was designed to characterize the genetic diversity of EVs among captive and wild NHP in Cameroon and to compare this diversity with that found in humans. Stool specimens were collected in April 2008 in NHP housed in sanctuaries in Yaounde and neighborhoods. Moreover, stool specimens collected from wild NHP from June 2006 to October 2008 in the southern rain forest of Cameroon were considered. RNAs purified directly from stool samples were screened for EVs using a sensitive RT-nested PCR targeting the VP1 capsid coding gene whose nucleotide sequence was used for molecular typing. Captive chimpanzees (Pan troglodytes) and gorillas (Gorilla gorilla) were primarily infected by EV types already reported in humans in Cameroon and elsewhere: Coxsackievirus A13 and A24, Echovirus 15 and 29, and EV-B82. Moreover EV-A119, a novel virus type recently described in humans in central and west Africa, was also found in a captive Chimpanzee. EV-A76, which is a widespread virus in humans, was identified in wild chimpanzees, thus suggesting its adaptation and parallel circulation in human and NHP populations in Cameroon. Interestingly, some EVs harbored by wild NHP were genetically distinct from all existing types and were thus assigned as new types. One chimpanzee-derived virus was tentatively assigned as EV-J121 in the EV-J species. In addition, two EVs from wild monkeys provisionally registered as EV-122 and EV-123 were found to belong to a candidate new species. Overall, this study indicates that the genetic diversity of EVs among NHP is more important than previously known and could be the source of future new emerging human viral diseases. PMID:25079078

Sadeuh-Mba, Serge Alain; Bessaud, Maël; Joffret, Marie-Line; Endegue Zanga, Marie-Claire; Balanant, Jean; Mpoudi Ngole, Eitel; Njouom, Richard; Reynes, Jean-Marc; Delpeyroux, Francis; Rousset, Dominique

2014-07-01

30

Characterization of Enteroviruses from Non-Human Primates in Cameroon Revealed Virus Types Widespread in Humans along with Candidate New Types and Species  

PubMed Central

Enteroviruses (EVs) infecting African Non-Human Primates (NHP) are still poorly documented. This study was designed to characterize the genetic diversity of EVs among captive and wild NHP in Cameroon and to compare this diversity with that found in humans. Stool specimens were collected in April 2008 in NHP housed in sanctuaries in Yaounde and neighborhoods. Moreover, stool specimens collected from wild NHP from June 2006 to October 2008 in the southern rain forest of Cameroon were considered. RNAs purified directly from stool samples were screened for EVs using a sensitive RT-nested PCR targeting the VP1 capsid coding gene whose nucleotide sequence was used for molecular typing. Captive chimpanzees (Pan troglodytes) and gorillas (Gorilla gorilla) were primarily infected by EV types already reported in humans in Cameroon and elsewhere: Coxsackievirus A13 and A24, Echovirus 15 and 29, and EV-B82. Moreover EV-A119, a novel virus type recently described in humans in central and west Africa, was also found in a captive Chimpanzee. EV-A76, which is a widespread virus in humans, was identified in wild chimpanzees, thus suggesting its adaptation and parallel circulation in human and NHP populations in Cameroon. Interestingly, some EVs harbored by wild NHP were genetically distinct from all existing types and were thus assigned as new types. One chimpanzee-derived virus was tentatively assigned as EV-J121 in the EV-J species. In addition, two EVs from wild monkeys provisionally registered as EV-122 and EV-123 were found to belong to a candidate new species. Overall, this study indicates that the genetic diversity of EVs among NHP is more important than previously known and could be the source of future new emerging human viral diseases. PMID:25079078

Sadeuh-Mba, Serge Alain; Bessaud, Maël; Joffret, Marie-Line; Endegue Zanga, Marie-Claire; Balanant, Jean; Mpoudi Ngole, Eitel; Njouom, Richard; Reynes, Jean-Marc; Delpeyroux, Francis; Rousset, Dominique

2014-01-01

31

Chemical modification of the plant isoprenoid cytokinin N(6)-isopentenyladenosine yields a selective inhibitor of human enterovirus 71 replication.  

PubMed

In this study, we demonstrate that N(6)-isopentenyladenosine, which essentially is a plant cytokinin-like compound, exerts a potent and selective antiviral effect on the replication of human enterovirus 71 with an EC50 of 1.0 ± 0.2 ?M and a selectivity index (SI) of 5.7. The synthesis of analogs with modification of the N(6)-position did not result in a lower EC50 value. However, in particular with the synthesis of N(6)-(5-hexene-2-yne-1-yl)adenosine (EC50 = 4.3 ± 1.5 ?M), the selectivity index was significantly increased: because of a reduction in the adverse effect of this compound on the host cells, an SI > 101 could be calculated. With this study, we for the first time provide proof that a compound class that is based on the plant cytokinin skeleton offers an interesting starting point for the development of novel antivirals against mammalian viruses, in the present context in particular against enterovirus 71. PMID:25461889

Tararov, Vitali I; Tijsma, Aloys; Kolyachkina, Svetlana V; Oslovsky, Vladimir E; Neyts, Johan; Drenichev, Mikhail S; Leyssen, Pieter; Mikhailov, Sergey N

2015-01-27

32

The association of recombination events in the founding and emergence of subgenogroup evolutionary lineages of human enterovirus 71.  

PubMed

Enterovirus 71 (EV71) is responsible for frequent large-scale outbreaks of hand, foot, and mouth disease worldwide and represent a major etiological agent of severe, sometimes fatal neurological disease. EV71 variants have been classified into three genogroups (GgA, GgB, and GgC), and the latter two are further subdivided into subgenogroups B1 to B5 and C1 to C5. To investigate the dual roles of recombination and evolution in the epidemiology and transmission of EV71 worldwide, we performed a large-scale genetic analysis of isolates (n = 308) collected from 19 countries worldwide over a 40-year period. A series of recombination events occurred over this period, which have been identified through incongruities in sequence grouping between the VP1 and 3Dpol regions. Eleven 3Dpol clades were identified, each specific to EV71 and associated with specific subgenogroups but interspersed phylogenetically with clades of coxsackievirus A16 and other EV species A serotypes. The likelihood of recombination increased with VP1 sequence divergence; mean half-lives for EV71 recombinant forms (RFs) of 6 and 9 years for GgB and GgC overlapped with those observed for the EV-B serotypes, echovirus 9 (E9), E30, and E11, respectively (1.3 to 9.8 years). Furthermore, within genogroups, sporadic recombination events occurred, such as the linkage of two B4 variants to RF-W instead of RF-A and of two C4 variants to RF-H. Intriguingly, recombination events occurred as a founding event of most subgenogroups immediately preceding their lineage expansion and global emergence. The possibility that recombination contributed to their subsequent spread through improved fitness requires further biological and immunological characterization. PMID:22205739

McWilliam Leitch, E C; Cabrerizo, M; Cardosa, J; Harvala, H; Ivanova, O E; Koike, S; Kroes, A C M; Lukashev, A; Perera, D; Roivainen, M; Susi, P; Trallero, G; Evans, D J; Simmonds, P

2012-03-01

33

Display of VP1 on the Surface of Baculovirus and Its Immunogenicity against Heterologous Human Enterovirus 71 Strains in Mice  

PubMed Central

Background Human Enterovirus 71 (EV71) is a common cause of hand, foot and mouth disease (HFMD) in young children. It is often associated with severe neurological diseases and has caused high mortalities in recent outbreaks across the Asia Pacific region. Currently, there is no effective vaccine and antiviral agents available against EV71 infections. VP1 is one of the major immunogenic capsid protein of EV71 and plays a crucial role in viral infection. Antibodies against VP1 are important for virus neutralization. Methodology/Principal Finding In the present study, infectious EV71 viruses were generated from their synthetic complementary DNA using the human RNA polymerase I reverse genetics system. Secondly, the major immunogenic capsid protein (VP1) of EV71-Fuyang (subgenogroup C4) was displayed on the surface of recombinant baculovirus Bac-Pie1-gp64-VP1 as gp64 fusion protein under a novel White Spot Syndrome Virus (WSSV) immediate early ie1 promoter. Baculovirus expressed VP1 was able to maintain its structural and antigenic conformity as indicated by immunofluorescence assay and western blot analysis. Interestingly, our results with confocal microscopy revealed that VP1 was able to localize on the plasma membrane of insect cells infected with recombinant baculovirus. In addition, we demonstrated with transmission electron microscopy that baculovirus successfully acquired VP1 from the insect cell membrane via the budding process. After two immunizations in mice, Bac-Pie1-gp64-VP1 elicited neutralization antibody titer of 1?64 against EV71 (subgenogroup C4) in an in vitro neutralization assay. Furthermore, the antisera showed high cross-neutralization activities against all 11 subgenogroup EV71 strains. Conclusion Our results illustrated that Bac-Pie1-gp64-VP1 retained native epitopes of VP1 and acted as an effective EV71 vaccine candidate which would enable rapid production without any biosafety concerns. PMID:21747954

Kiener, Tanja K.; Chow, Vincent T. K.; Kwang, Jimmy

2011-01-01

34

Enteroviruses, hygiene and type 1 diabetes: toward a preventive vaccine.  

PubMed

Enteroviruses and humans have long co-existed. Although recognized in ancient times, poliomyelitis and type 1 diabetes (T1D) were exceptionally rare and not epidemic, due in large part to poor sanitation and personal hygiene which resulted in repeated exposure to fecal-oral transmitted viruses and other infectious agents and viruses and the generation of a broad protective immunity. As a function of a growing acceptance of the benefits of hygienic practices and microbiologically clean(er) water supplies, the likelihood of exposure to diverse infectious agents and viruses declined. The effort to vaccinate against poliomyelitis demonstrated that enteroviral diseases are preventable by vaccination and led to understanding how to successfully attenuate enteroviruses. Type 1 diabetes onset has been convincingly linked to infection by numerous enteroviruses including the group B coxsackieviruses (CVB), while studies of CVB infections in NOD mice have demonstrated not only a clear link between disease onset but an ability to reduce the incidence of T1D as well: CVB infections can suppress naturally occurring autoimmune T1D. We propose here that if we can harness and develop the capacity to use attenuated enteroviral strains to induce regulatory T cell populations in the host through vaccination, then a vaccine could be considered that should function to protect against both autoimmune as well as virus-triggered T1D. Such a vaccine would not only specifically protect from certain enterovirus types but more importantly, also reset the organism's regulatory rheostat making the further development of pathogenic autoimmunity less likely. Copyright © 2014 John Wiley & Sons, Ltd. PMID:25430610

Drescher, Kristen M; von Herrath, Matthias; Tracy, Steven

2015-01-01

35

Human Astrocytic Cells Support Persistent Coxsackievirus B3 Infection  

PubMed Central

Enteroviruses can frequently target the human central nervous system to induce a variety of neurological diseases. Although enteroviruses are highly cytolytic, emerging evidence has shown that these viruses can establish persistent infections both in vivo and in vitro. Here, we investigated the susceptibility of three human brain cell lines, CCF-STTG1, T98G, and SK-N-SH, to infection with three enterovirus serotypes: coxsackievirus B3 (CVB3), enterovirus 71, and coxsackievirus A9. Persistent infection was observed in CVB3-infected CCF-STTG1 cells, as evidenced by prolonged detection of infectious virions, viral RNA, and viral antigens. Of note, infected CCF-STTG1 cells expressed the nonfunctional canonical viral receptors coxsackievirus-adenovirus receptor and decay-accelerating factor, while removal of cell surface chondroitin sulfate from CCF-STTG1 cells inhibited the replication of CVB3, suggesting that receptor usage was one of the major limiting factors in CVB3 persistence. In addition, CVB3 curtailed the induction of beta interferon in infected CCF-STTG1 cells, which likely contributed to the initiation of persistence. Furthermore, proinflammatory chemokines and cytokines, such as vascular cell adhesion molecule 1, interleukin-8 (IL-8), and IL-6, were upregulated in CVB3-infected CCF-STTG1 cells and human progenitor-derived astrocytes. Our data together demonstrate the potential of CCF-STTG1 cells to be a novel cell model for studying CVB3-central nervous system interactions, providing the basis toward a better understanding of CVB3-induced chronic neuropathogenesis. PMID:24027313

Zhang, Xiaowei; Zheng, Zhenhua; Shu, Bo; Liu, Xijuan; Zhang, Zhenfeng; Liu, Yan; Bai, Bingke; Hu, Qinxue

2013-01-01

36

Enterovirus D68  

MedlinePLUS

... should people with asthma and children suffering from reactive airway disease do? Children with asthma are at ... infections Enterovirus D68 (EV-D68) Resources Related Links Water-related Hygiene Viral Conjunctivitis Hand, Foot, and Mouth ...

37

21 CFR 866.3225 - Enterovirus nucleic acid assay.  

Code of Federal Regulations, 2012 CFR

... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3225 Enterovirus nucleic acid assay. (a)...

2012-04-01

38

21 CFR 866.3225 - Enterovirus nucleic acid assay.  

Code of Federal Regulations, 2010 CFR

... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3225 Enterovirus nucleic acid assay. (a)...

2010-04-01

39

Impact of diagnostic procedures on patient management and hospitalization cost during the 2000 and 2005 enterovirus epidemics in Marseilles, France.  

PubMed

Enteroviruses are frequent aetiological agents of central nervous system infections in humans. In 2000 and 2005, two large outbreaks of Echovirus 30 (a member of species human enterovirus B) were observed in the University Hospitals of Marseilles (France). Between the two epidemics, the diagnostic protocols for enterovirus infection were modified, moving from viral cultures and classic RT-PCR in 2000 to real-time RT-PCR in 2005. We compared some viral and epidemiological characteristics of the 2000 and 2005 outbreaks with special attention to diagnostic procedures and to the subsequent clinical management of patients. Despite similar virological and epidemiological characteristics during both outbreaks, our results show that real-time RT-PCR techniques used in 2005 noticeably shortened the period of time necessary to deliver diagnostic results and suggest that this was associated with a decrease in the duration of hospitalization for positive cases. In conclusion, this study suggests that the improvement of enterovirus diagnosis had a major financial impact on the management of the 2005 epidemic in Marseilles and may constitute an interesting example of how new diagnostic methods in microbiology can be self-financed through improvement in patient management. PMID:20015267

Ninove, L; Tan, C; Nougairede, A; Zandotti, C; Richet, H; Charrel, R; de Lamballerie, X

2010-06-01

40

Enterovirus 71 VP1 Activates Calmodulin-Dependent Protein Kinase II and Results in the Rearrangement of Vimentin in Human Astrocyte Cells  

PubMed Central

Enterovirus 71 (EV71) is one of the main causative agents of foot, hand and mouth disease. Its infection usually causes severe central nervous system diseases and complications in infected infants and young children. In the present study, we demonstrated that EV71 infection caused the rearrangement of vimentin in human astrocytoma cells. The rearranged vimentin, together with various EV71 components, formed aggresomes-like structures in the perinuclear region. Electron microscopy and viral RNA labeling indicated that the aggresomes were virus replication sites since most of the EV71 particles and the newly synthesized viral RNA were concentrated here. Further analysis revealed that the vimentin in the virus factories was serine-82 phosphorylated. More importantly, EV71 VP1 protein is responsible for the activation of calmodulin-dependent protein kinase II (CaMK-II) which phosphorylated the N-terminal domain of vimentin on serine 82. Phosphorylation of vimentin and the formation of aggresomes were required for the replication of EV71 since the latter was decreased markedly after phosphorylation was blocked by KN93, a CaMK-II inhibitor. Thus, as one of the consequences of CaMK-II activation, vimentin phosphorylation and rearrangement may support virus replication by playing a structural role for the formation of the replication factories. Collectively, this study identified the replication centers of EV71 in human astrocyte cells. This may help us understand the replication mechanism and pathogenesis of EV71 in human. PMID:24073199

Haolong, Cong; Du, Ning; Hongchao, Tian; Yang, Yang; Wei, Zhang; Hua, Zhang; Wenliang, Zhang; Lei, Song; Po, Tien

2013-01-01

41

Detection of Infectious Enteroviruses, Enterovirus Genomes, Somatic Coliphages, and Bacteroides fragilis Phages in Treated Wastewater  

Microsoft Academic Search

In this study, three types of treated wastewater were tested for infectious enteroviruses, the enterovirus genome, somatic coliphages, and Bacteroides fragilis phages. The aim of this work was to determine whether the presence of the two types of bacteriophages or of the enterovirus genome was a good indicator of infectious enterovirus contamination. The enterovirus genome was detected by reverse transcription-polymerase

C. GANTZER; A. MAUL; J. M. AUDIC; L. SCHWARTZBROD; Facultede Pharmacie

1998-01-01

42

Genetic clustering of all 102 human rhinovirus prototype strains: serotype 87 is close to human enterovirus 70  

Microsoft Academic Search

Human rhinoviruses (HRV), common agents of respiratory infections, comprise 102 designated serotypes. The genetic relationships of HRV prototype strains and the possibility of using genetic identification of a given HRV field strain were studied. Genomic sequences in the VP4\\/VP2 region were obtained from all 102 prototype strains. Phylogenetic analysis included 61 recently isolated Finnish field strains. Seventy-six out of the

Carita Savolainen; Soile Blomqvist; Mick N. Muldersã; Tapani Hovi

2002-01-01

43

Complete coding regions of the prototypes enterovirus B93 and C95: Phylogenetic analyses of the P1 and P3 regions of EV-B and EV-C strains.  

PubMed

Complete coding regions were sequenced for two new enterovirus genomes: EV-B93 previously identified by VP1 sequencing, derived from a child with acute flaccid paralysis in the Democratic Republic of Congo; and EV-C95 from a French soldier with acute gastroenteritis in Djibouti. The EV-B93 P1 had more than 30% nucleotide divergence from other EV-B types, with highest similarity to E-15 and EV-B80. The P1 nucleotide sequence of EV-C95 was most similar, 71%, to CV-A21. Complete coding regions for the new enteroviruses were compared with those of 135 EV-B and 176 EV-C strains representing all types available in GenBank. When strains from the same outbreak or strains isolated during the same year in the same geographical region were excluded, 27 of the 58 EV-B, and 16 of the 23 EV-C types were represented by more than one sequence. However, for EV-B the P3 sequences formed three clades mainly according to origin or time of isolation, irrespective of type, while for EV-C the P3 sequences segregated mainly according to disease manifestation, with most strains causing paralysis, including polioviruses, forming one clade, and strains causing respiratory illness forming another. There was no intermixing of types between these two clades, apart from two EV-C96 strains. The EV-B P3 sequences had lower inter-clade and higher intra-clade variability as compared to the EV-C sequences, which may explain why inter-clade recombinations are more frequent in EV-B. Further analysis of more isolates may shed light on the role of recombinations in the evolution of EV-B in geographical context. J. Med. Virol. 87:485-497, 2015. © 2014 Wiley Periodicals, Inc. PMID:25163640

Junttila, N; Lévêque, N; Magnius, L O; Kabue, J P; Muyembe-Tamfum, J J; Maslin, J; Lina, B; Norder, H

2015-03-01

44

Assessment of the risks for human health of adenoviruses, hepatitis A virus, rotaviruses and enteroviruses in the Buffalo River and three source water dams in the Eastern Cape.  

PubMed

Buffalo River is an important water resource in the Eastern Cape Province of South Africa. The potential risks of infection constituted by exposure to human enteric viruses in the Buffalo River and three source water dams along its course were assessed using mean values and static quantitative microbial risk assessment (QMRA). The daily risks of infection determined by the exponential model [for human adenovirus (HAdV) and enterovirus (EnV)] and the beta-Poisson model (for hepatitis A virus (HAV) and rotavirus (RoV)) varied with sites and exposure scenario. The estimated daily risks of infection values at the sites where the respective viruses were detected, ranged from 7.31 × 10(-3) to 1 (for HAdV), 4.23 × 10(-2) to 6.54 × 10(-1) (RoV), 2.32 × 10(-4) to 1.73 × 10(-1) (HAV) and 1.32 × 10(-4) to 5.70 × 10(-2) (EnV). The yearly risks of infection in individuals exposed to the river/dam water via drinking, recreational, domestic or irrigational activities were unacceptably high, exceeding the acceptable risk of 0.01% (10(-4) infection/person/year), and the guideline value used as by several nations for drinking water. The risks of illness and death from infection ranged from 6.58 × 10(-5) to 5.0 × 10(-1) and 6.58 × 10(-9) to 5.0 × 10(-5), respectively. The threats here are heightened by the high mortality rates for HAV, and its endemicity in South Africa. Therefore, we conclude that the Buffalo River and its source water dams are a public health hazard. The QMRA presented here is the first of its kinds in the Eastern Cape Province and provides the building block for a quantitatively oriented local guideline for water quality management in the Province. PMID:24676673

Chigor, Vincent N; Sibanda, Timothy; Okoh, Anthony I

2014-06-01

45

What Is Enterovirus D68?  

MedlinePLUS

... to the classroom after winter break. Strains of Viruses The D68 refers to the specific strain of ... There is no vaccine currently for enteroviruses. How Viruses Spread and How to Avoid Getting Sick Like ...

46

Human MicroRNA hsa-miR-296-5p Suppresses Enterovirus 71 Replication by Targeting the Viral Genome  

PubMed Central

Enterovirus 71 (EV71) has emerged as a major cause of neurological disease following the near eradication of poliovirus. Accumulating evidence suggests that mammalian microRNAs (miRNAs), a class of noncoding RNAs of 18 to 23 nucleotides (nt) with important regulatory roles in many cellular processes, participate in host antiviral defenses. However, the roles of miRNAs in EV71 infection and pathogenesis are still unclear. Here, hsa-miR-296-5p expression was significantly increased in EV71-infected human cells. As determined by virus titration, quantitative real-time PCR (qRT-PCR), and Western blotting, overexpression of hsa-miR-296-5p inhibited, while inhibition of endogenous hsa-miR-296-5p facilitated, EV71 infection. Additionally, two potential hsa-miR-296-5p targets (nt 2115 to 2135 and nt 2896 to 2920) located in the EV71 genome (strain BrCr) were bioinformatically predicted and validated by luciferase reporter assays and Western blotting. Genomic alignment of various EV71 strains revealed synonymous mutations in hsa-miR-296-5p target sequences. Furthermore, the introduction of synonymous mutations into the EV71 BrCr genome by site-directed mutagenesis impaired the viral inhibitory effects of hsa-miR-296-5p and facilitated mutant virus infection. Meanwhile, compensatory mutations in corresponding hsa-miR-296-5p target sequences of the EV71 HeN strain (GenBank accession number JN256064) restored the inhibitory effects of the miRNA. These results indicate that hsa-miR-296-5p inhibits EV71 replication by targeting the viral genome. Our findings support the notion that cellular miRNAs can inhibit virus infection and that the virus mutates to escape suppression by cellular miRNAs. PMID:23468506

Zheng, Zhenhua; Ke, Xianliang; Wang, Meng; He, Siyi; Li, Qian; Zheng, Caishang; Zhang, Zhenfeng; Liu, Yan

2013-01-01

47

Evidence for an enterovirus as the cause of encephalitis lethargica  

PubMed Central

Background The epidemic of encephalitis lethargica (EL), called classical EL, was rampant throughout the world during 1917–1926, affecting half a million persons. The acute phase was lethal for many victims. Post-encephalitic parkinsonism (PEP) affected patients for decades. Our purpose was to investigate the cause of classical EL by studying the few available brain specimens. Cases of PEP and modern EL were also studied. Transmission electron microscopy (TEM) and immunohistochemistry were employed to examine brain from four classical EL cases, two modern EL cases and one PEP case. Methods Standard methods for TEM, immunohistochemistry and RTPCR were applied. Results 27?nm virus-like particles (VLP) were observed in the cytoplasm and nuclei of midbrain neurons in all classical EL cases studied. Large (50?nm) VLP and 27?nm intranuclear VLP were observed in the modern EL cases and the PEP case. Influenza virus particles were not found. VLP were not observed in the control cases. TEM of cell cultures inoculated with coxsackievirus B4 and poliovirus revealed both small and large intranuclear virus particles and small cytoplasmic particles, similar to the VLP in EL neurons. In the EL brains, nascent VLP were embedded in putative virus factories and on endoplasmic reticulum (ER). The VLP in the cases of classical EL survived, whereas ribosomes underwent autolysis due to the lack of refrigeration and slow formaldehyde fixation of whole brain. The VLP were larger than ribosomes from well preserved brain. Immunohistochemistry of classical EL cases using anti-poliovirus and anti-coxsackievirus B polyclonal antibodies showed significant staining of cytoplasm and nuclei of neurons as well as microglia and neuropil. Purkinje cells were strongly stained. A 97-bp RNA fragment of a unique virus was isolated from brain tissue from acute EL case #91558. Sequence analysis revealed up to 95% identity to multiple human Enteroviruses. Additional cases had Enterovirus positive reactions by real time PCR. Conclusions The data presented here support the hypothesis that the VLP observed in EL tissue is an Enterovirus. PMID:22715890

2012-01-01

48

Enterovirus 75 Encephalitis in Children, Southern India  

PubMed Central

Recent outbreaks of enterovirus in Southeast Asia emphasize difficulties in diagnosis of this infection. To address this issue, we report 5 (4.7%) children infected with enterovirus 75 among 106 children with acute encephalitis syndrome during 2005–2007 in southern India. Throat swab specimens may be useful for diagnosis of enterovirus 75 infection. PMID:21029544

Perera, David; Ooi, Mong How; Last, Anna; Kumar, Ravi; Desai, Anita; Begum, Ashia; Ravi, Vasanthapuram; Shankar, M. Veera; Tio, Phaik Hooi; Cardosa, Mary Jane; Solomon, Tom

2010-01-01

49

Review of Enterovirus 71 Vaccines.  

PubMed

Enterovirus 71 (EV71) and coxsackieviruses are the major causative agents of hand, foot, and mouth disease (HFMD) outbreaks worldwide and have a significant socioeconomic impact, particularly in Asia. Formalin-inactivated (FI) EV71 vaccines evaluated in human clinical trials in China, Taiwan, and Singapore were found to be safe and to elicit strong neutralizing antibody responses against EV71 currently circulating in Asia. The results from 3 different phase 3 clinical trials performed in young children (6-60 months) indicate that the efficacy of FI-EV71 vaccines is >90% against EV71-related HFMDs and >80% against EV71-associated serious diseases, but the vaccines did not protect against coxsackievirus A16 infections. Here we discuss the critical factors affecting EV71 vaccine product registration, including clinical epidemiology, antigenic shift issues in cross-protection and vaccine strain selection, standardized animal models for potency testing, and cost-effective manufacturing processes for potential incorporation of FI-EV71 vaccine into Expanded Programme on Immunization vaccines. PMID:25352588

Chong, Pele; Liu, Chia-Chyi; Chow, Yen-Hung; Chou, Ai-Hsiang; Klein, Michel

2014-10-28

50

The HeLa cell receptor for enterovirus 70 is decay-accelerating factor (CD55).  

PubMed Central

Enterovirus 70 (EV70) is a recently emerged human pathogen belonging to the family Picornaviridae. The ability of EV70 to infect a wide variety of nonprimate cell lines in vitro is unique among human enteroviruses. The importance of virus receptors as determinants of viral host range and tropism led us to study the host cell receptor for this unusual picornavirus. We produced a monoclonal antibody (MAb), EVR1, which bound to the surface of HeLa cells and protected them against infection by EV70 but not by poliovirus or by coxsackievirus B3. This antibody also inhibited the binding of [35S]EV70 to HeLa cells. MAb EVR1 did not bind to monkey kidney (LLC-MK2) cells, nor did it protect these cells against virus infection. In Western immunoassays and in immunoprecipitations, MAb EVR1 identified a HeLa cell glycoprotein of approximately 75 kDa that is attached to the cell membrane by a glycosyl-phosphatidylinositol (GPI) anchor. Decay-accelerating factor (DAF, CD55) is a 70- to 75-kDa GPI-anchored membrane protein that is involved in the regulation of complement and has also been shown to function as a receptor for several enteroviruses. MAb EVR1 bound to Chinese hamster ovary (CHO) cells constitutively expressing human DAF. Anti-DAF MAbs inhibited EV70 binding to HeLa cells and protected them against EV70 infection. Transient expression of human DAF in murine NIH 3T3 cells resulted in binding of labelled EV70 and stably, transformed NIH 3T3 cells expressing DAF were able to support virus replication. These data indicate that the HeLa cell receptor for EV70 is DAF. PMID:8764022

Karnauchow, T M; Tolson, D L; Harrison, B A; Altman, E; Lublin, D M; Dimock, K

1996-01-01

51

Identification of a series of compounds with potent antiviral activity for the treatment of enterovirus infections.  

PubMed

Rhinovirus (genus enterovirus) infections are responsible for many of the severe exacerbations of asthma and chronic obstructive pulmonary disease. Other members of the genus can cause life-threatening acute neurological infections. There is currently no antiviral drug approved for the treatment of such infections. We have identified a series of potent, broad-spectrum antiviral compounds that inhibit the replication of the human rhinovirus, Coxsackie virus, poliovirus, and enterovirus-71. The mechanism of action of the compounds has been established as inhibition of a lipid kinase, PI4KIII?. Inhibition of hepatitis C replication in a replicon assay correlated with enterovirus inhibition. PMID:24900715

MacLeod, Angus M; Mitchell, Dale R; Palmer, Nicholas J; Van de Poël, Hervé; Conrath, Katja; Andrews, Martin; Leyssen, Pieter; Neyts, Johan

2013-07-11

52

Structure determination of enterovirus 71  

SciTech Connect

Enterovirus 71 is a picornavirus that causes hand, foot and mouth disease but may induce fatal neurological illness in infants and young children. Enterovirus 71 crystallized in a body-centered orthorhombic space group with two particles in general orientations in the crystallographic asymmetric unit. Determination of the particle orientations required that the locked rotation function excluded the twofold symmetry axes from the set of icosahedral symmetry operators. This avoided the occurrence of misleading high rotation-function values produced by the alignment of icosahedral and crystallographic twofold axes. Once the orientations and positions of the particles had been established, the structure was solved by molecular replacement and phase extension.

Plevka, Pavel; Perera, Rushika; Cardosa, Jane; Kuhn, Richard J.; Rossmann, Michael G. (Purdue); (Sentinext)

2013-02-20

53

Enterovirus 74 Infection in Children  

PubMed Central

Enterovirus 74 (EV74) is a rarely detected viral infection of children. In 2010, EV74 was identified in New Zealand in a 2 year old child with acute flaccid paralysis (AFP) through routine polio AFP surveillance. A further three cases of EV74 were identified in children within six months. These cases are the first report of EV74 in New Zealand. In this study we describe the near complete genome sequence of four EV74 isolates from New Zealand, which shows only limited sequence identity in the non-structural proteins when compared to the other two known EV74 sequences. As is typical of enteroviruses multiple recombination events were evident, particularly in the P2 region and P3 regions. This is the first complete EV74 genome sequenced from a patient with acute flaccid paralysis. PMID:24098514

Peacey, Matthew; Hall, Richard J.; Wang, Jing; Todd, Angela K.; Yen, Seiha; Chan-Hyams, Jasmine; Rand, Christy J.; Stanton, Jo-Ann; Huang, Q. Sue

2013-01-01

54

High Rates of Infection with Novel Enterovirus Variants in Wild Populations of Mandrills and Other Old World Monkey Species  

PubMed Central

ABSTRACT Enteroviruses (EVs) are a genetically and antigenically diverse group of viruses infecting humans. A mostly distinct set of EV variants have additionally been documented to infect wild apes and several, primarily captive, Old World monkey (OWM) species. To investigate the prevalence and genetic characteristics of EVs infecting OWMs in the wild, fecal samples from mandrills (Mandrillus sphinx) and other species collected in remote regions of southern Cameroon were screened for EV RNA. Remarkably high rates of EV positivity were detected in M. sphinx (100 of 102 screened), Cercocebus torquatus (7/7), and Cercopithecus cephus (2/4), with high viral loads indicative of active infection. Genetic characterization in VP4/VP2 and VP1 regions allowed EV variants to be assigned to simian species H (EV-H) and EV-J (including one or more new types), while seven matched simian EV-B variants, SA5 and EV110 (chimpanzee). Sequences from the remaining 70 formed a new genetic group distinct in VP4/2 and VP1 region from all currently recognized human or simian EV species. Complete genome sequences were obtained from three to determine their species assignment. In common with EV-J and the EV-A A13 isolate, new group sequences were chimeric, being most closely related to EV-A in capsid genes and to EV-B in the nonstructural gene region. Further recombination events created different groupings in 5? and 3? untranslated regions. While clearly a distinct EV group, the hybrid nature of new variants prevented their unambiguous classification as either members of a new species or as divergent members of EV-A using current International Committee on Taxonomy of Viruses (ICTV) assignment criteria. IMPORTANCE This study is the first large-scale investigation of the frequency of infection and diversity of enteroviruses (EVs) infecting monkeys (primarily mandrills) in the wild. Our findings demonstrate extremely high frequencies of active infection (95%) among mandrills and other Old World monkey species inhabiting remote regions of Cameroon without human contact. EV variants detected were distinct from those infecting human populations, comprising members of enterovirus species B, J, and H and a large novel group of viruses most closely related to species A in the P1 region. The viral sequences obtained contribute substantially to our growing understanding of the genetic diversity of EVs and the existence of interspecies chimerism that characterizes the novel variants in the current study, as well as in previously characterized species A and J viruses infecting monkeys. The latter findings will contribute to future development of consensus criteria for species assignments in enteroviruses and other picornavirus genera. PMID:24623420

Nguyen, Dung Van; Harvala, Heli; Ngole, Eitel Mpoudi; Delaporte, Eric; Woolhouse, Mark E. J.; Peeters, Martine

2014-01-01

55

[Neonatal enterovirus infections reported in France in 2012].  

PubMed

Enteroviruses (EVs) are among the most common viruses infecting humans. One-third of EV infections affect children under 1 year of age. Neonatal EV infections lead to a wide range of clinical manifestations, from mild febrile illness to severe, potentially fatal sepsis-like conditions with multiorgan failure. EV detections by serotype are reported by the National Reference Centre for EV Infections Lyon on a monthly basis. Demographic, clinical, and biological data were also collected in neonates hospitalized in 2012 for EV infection. Two subgroups were identified according to the beginning of symptoms: until 8 days of life (D8) or strictly after D8. There were 120 neonatal EV infections. Before D8, children with severe infection were born more prematurely with a low birth weight. The EVs most commonly detected in neonates were CV-B4 and E-11. Risk factors for severe EV infections included liver (73% before D8) and hematological damage (thrombocytopenia, 82%; coagulopathy, 64% before D8). This study suggests that systematic serotyping of neonatal EV infections and biological monitoring of liver function could be useful for early identification of children at high risk of clinical severity and fatality. PMID:25126719

Soudée, S; Schuffenecker, I; Aberchih, J; Josset, L; Lina, B; Baud, O; Biran, V

2014-09-01

56

Symmetry-Related Clustering of Positive Charges Is a Common Mechanism for Heparan Sulfate Binding in Enteroviruses  

PubMed Central

Coxsackievirus A9 (CAV9), a member of the Picornaviridae family, uses an RGD motif in the VP1 capsid protein to bind to integrin ?v?6 during cell entry. Here we report that two CAV9 isolates can bind to the heparan sulfate/heparin class of proteoglycans (HSPG). Sequence analysis identified an arginine (R) at position 132 in VP1 in these two isolates, rather than a threonine (T) as seen in the nonbinding strains tested. We introduced a T132R substitution into the HSPG-nonbinding strain Griggs and recovered infectious virus capable of binding to immobilized heparin, unlike the parental Griggs strain. The known CAV9 structure was used to identify the location of VP1 position 132, 5 copies of which were found to cluster around the 5-fold axis of symmetry, presumably producing a region of positive charge which can interact with the negatively charged HSPG. Analysis of several enteroviruses of the same species as CAV9, Human enterovirus B (HEV-B), identified examples from 5 types in which blocking of infection by heparin was coincident with an arginine (or another basic amino acid, lysine) at a position corresponding to 132 in VP1 in CAV9. Together, these data show that membrane-associated HSPG can serve as a (co)receptor for some CAV9 and other HEV-B strains and identify symmetry-related clustering of positive charges as one mechanism by which HSPG binding can be achieved. This is a potentially powerful mechanism by which a single amino acid change could generate novel receptor binding capabilities, underscoring the plasticity of host-cell interactions in enteroviruses. PMID:22855495

McLeish, Nigel J.; Williams, Çi?dem H.; Kaloudas, Dimitrios; Roivainen, Merja M.

2012-01-01

57

21 CFR 866.3225 - Enterovirus nucleic acid assay.  

Code of Federal Regulations, 2011 CFR

...Identification . An enterovirus nucleic acid assay is a device that consists...detection of enterovirus ribonucleic acid (RNA) in cerebrospinal...The special control is FDA's guidance document entitled...Controls Guidance Document: Nucleic Acid Amplification Assay for the...

2011-04-01

58

21 CFR 866.3225 - Enterovirus nucleic acid assay.  

Code of Federal Regulations, 2013 CFR

...Identification . An enterovirus nucleic acid assay is a device that consists...detection of enterovirus ribonucleic acid (RNA) in cerebrospinal...The special control is FDA's guidance document entitled...Controls Guidance Document: Nucleic Acid Amplification Assay for the...

2013-04-01

59

21 CFR 866.3225 - Enterovirus nucleic acid assay.  

...Identification. An enterovirus nucleic acid assay is a device that consists...detection of enterovirus ribonucleic acid (RNA) in cerebrospinal...The special control is FDA's guidance document entitled...Controls Guidance Document: Nucleic Acid Amplification Assay for the...

2014-04-01

60

Prevalence of nonpolio enteroviruses in the sewage of Guangzhou city, China, from 2009 to 2012.  

PubMed

The human-pathogenic viruses in urban sewage have been extensively monitored to obtain information on circulating viruses in human communities. Enteroviruses (EVs) excreted by patients who present with diverse clinical syndromes can remain infectious in the environment for several weeks, and limited data on circulating environmental EVs are available. A 4-year (2009 to 2012) surveillance study was conducted to detect nonpolio enteroviruses (NPEVs) in the urban sewage of Guangzhou city, China. After the viruses in the sewage samples were concentrated and isolated, molecular identification was used to detect and type the NPEVs. During the 4-year study, 17 different NPEV serotypes were identified in the sewage of Guangzhou city. The most common serotypes were echovirus 11 (ECHO11), ECHO6, ECHO7, and ECHO12 and coxsackie group B viruses 5 (CVB5) and CVB3. The predominant serotypes were influenced by spatial and temporal factors and differed each year. CVB5 was commonly detected in 2009 and 2010 but was rarely isolated in 2011 and 2012. In contrast, CVB3 was not observed in 2009 and 2010 but was increasingly detected in 2011 and 2012. Our study provides an overview of the serotype distribution and circulation patterns of NPEVs in the sewage of Guangzhou, China. In the absence of a systematic EV disease surveillance system, the detection and characterization of sewage-borne NPEVs will help us better understand the changes in EV disease trends and the epidemic background of circulating EVs, which could help interpret the EV trends and warn of future outbreaks in this area. PMID:24096418

Zheng, Huanying; Lu, Jing; Zhang, Yong; Yoshida, Hiromu; Guo, Xue; Liu, Leng; Li, Hui; Zeng, Hanri; Fang, Ling; Mo, Yanling; Yi, Lina; Chosa, Toru; Xu, Wenbo; Ke, Changwen

2013-12-01

61

QUANTIFICATION OF ENTEROVIRUS AND HEPATITIS A VIRUSES IN WELLS AND SPRINGS IN EAST TENNESSEE USING REAL-TIME REVERSE TRANSCIPTION PCR  

EPA Science Inventory

This project involves development, validation testing and application of a fast, efficient method of quantitatively measuring occurrence and concentration of common human viral pathogens, enterovirus and hepatitis A virus, in ground water samples using real-time reverse transcrip...

62

ADSORPTION OF ENTEROVIRUSES TO SOIL CORES AND THEIR SUBSEQUENT ELUTION BY ARTIFICIAL RAINWATER  

EPA Science Inventory

The adsorption and elution of a variety of human enteroviruses in a highly permeable, sandy soil was studied by using cores (43 by 125 mm) collected from an operating recharge basin on Long Island. Viruses studied included field and reference strains of polioviruses types 1 and 3...

63

Proposals for the classification of human rhinovirus species A, B and C into genotypically assigned types.  

PubMed

Human rhinoviruses (HRVs) frequently cause mild upper respiratory tract infections and more severe disease manifestations such as bronchiolitis and asthma exacerbations. HRV is classified into three species within the genus Enterovirus of the family Picornaviridae. HRV species A and B contain 75 and 25 serotypes identified by cross-neutralization assays, although the use of such assays for routine HRV typing is hampered by the large number of serotypes, replacement of virus isolation by molecular methods in HRV diagnosis and the poor or absent replication of HRV species C in cell culture. To address these problems, we propose an alternative, genotypic classification of HRV-based genetic relatedness analogous to that used for enteroviruses. Nucleotide distances between 384 complete VP1 sequences of currently assigned HRV (sero)types identified divergence thresholds of 13, 12 and 13?% for species A, B and C, respectively, that divided inter- and intra-type comparisons. These were paralleled by 10, 9.5 and 10?% thresholds in the larger dataset of >3800 VP4 region sequences. Assignments based on VP1 sequences led to minor revisions of existing type designations (such as the reclassification of serotype pairs, e.g. A8/A95 and A29/A44, as single serotypes) and the designation of new HRV types A101-106, B101-103 and C34-C51. A protocol for assignment and numbering of new HRV types using VP1 sequences and the restriction of VP4 sequence comparisons to type identification and provisional type assignments is proposed. Genotypic assignment and identification of HRV types will be of considerable value in the future investigation of type-associated differences in disease outcomes, transmission and epidemiology. PMID:23677786

McIntyre, Chloe L; Knowles, Nick J; Simmonds, Peter

2013-08-01

64

Proposals for the classification of human rhinovirus species A, B and C into genotypically assigned types  

PubMed Central

Human rhinoviruses (HRVs) frequently cause mild upper respiratory tract infections and more severe disease manifestations such as bronchiolitis and asthma exacerbations. HRV is classified into three species within the genus Enterovirus of the family Picornaviridae. HRV species A and B contain 75 and 25 serotypes identified by cross-neutralization assays, although the use of such assays for routine HRV typing is hampered by the large number of serotypes, replacement of virus isolation by molecular methods in HRV diagnosis and the poor or absent replication of HRV species C in cell culture. To address these problems, we propose an alternative, genotypic classification of HRV-based genetic relatedness analogous to that used for enteroviruses. Nucleotide distances between 384 complete VP1 sequences of currently assigned HRV (sero)types identified divergence thresholds of 13, 12 and 13?% for species A, B and C, respectively, that divided inter- and intra-type comparisons. These were paralleled by 10, 9.5 and 10?% thresholds in the larger dataset of >3800 VP4 region sequences. Assignments based on VP1 sequences led to minor revisions of existing type designations (such as the reclassification of serotype pairs, e.g. A8/A95 and A29/A44, as single serotypes) and the designation of new HRV types A101–106, B101–103 and C34–C51. A protocol for assignment and numbering of new HRV types using VP1 sequences and the restriction of VP4 sequence comparisons to type identification and provisional type assignments is proposed. Genotypic assignment and identification of HRV types will be of considerable value in the future investigation of type-associated differences in disease outcomes, transmission and epidemiology. PMID:23677786

McIntyre, Chloe L.; Knowles, Nick J.

2013-01-01

65

New Approaches for Enhanced Detection of Enteroviruses from Hawaiian Environmental Waters  

PubMed Central

Health risks associated with sewage-contaminated recreational waters are of important public health concern. Reliable water monitoring systems are therefore crucial. Current recreational water quality criteria rely predominantly on the enumeration of bacterial indicators, while potentially dangerous viral pathogens often remain undetected. Human enteric viruses have been proposed as alternative indicators; however, their detection is often hindered by low viral concentrations present in the environment. Reported here are novel and effective laboratory protocols for viral concentration and highly sensitive and optimized RT-PCR for the efficient detection of enteroviruses, an important enteric virus subset, in Hawaiian environmental waters. Eighteen published enterovirus primer pairs were comparatively evaluated for detection sensitivity. The primer set exhibiting the lowest detection limit under optimized conditions, EQ-1/EQ-2, was validated in a field survey of 22 recreational bodies of water located around the island of Oahu, Hawaii. Eleven sites tested positive for enterovirus, indicating fecal contamination at these locations. As an additional means of viral concentration, shellfish were collected from 9 sample sites and subjected to dissection, RNA extraction, and subsequent RT-PCR. Shellfish tissue from 6 of 9 sites tested positive for enterovirus. The techniques implemented here are valuable resources to aid accurate reflection of microbial contamination in Hawaii’s environmental waters. PMID:22567083

Connell, Christina; Tong, Hsin-I; Wang, Zi; Allmann, Erin; Lu, Yuanan

2012-01-01

66

Genetic Diversity of Enterovirus A71, India  

PubMed Central

We have identified circulation of 3 genogroups of enterovirus (EV) A71 in India. A new genogroup (proposed designation G) was discovered during this study. We isolated genogroups D and G in wide geographic areas but detected subgenogroup C1 only in 1 focus in western India. A systematic nationwide search for EV-A71 is warranted. PMID:25531549

Saxena, Vinay K.; Sane, Sudhir; Nadkarni, Sushma S.; Sharma, Deepa K.

2015-01-01

67

Neutralizing antibodies to enterovirus 71 in Belém, Brazil.  

PubMed

Non-polio enteroviruses (Coxsackievirus A, Coxsackievirus B, Echovirus and EV 68-72) which belong to the enterovirus (EV) genus, Picornaviridae family, may be responsible for acute flaccid paralysis, aseptic meningitis, myocarditis, hepatitis, pleurodinia, neonatal sepsis, hand, foot and mouth disease (HFMD) even though 50-80% of infections are asymptomatic. EV 71 has been responsible for outbreaks and epidemics of HFMD and acute neurologic disease justifying its study in our country. The aim of this study was to detect neutralizing antibodies (NtAb) to EV 71 in individuals up to 15 years of age living in Belém, State of Pará, northern Brazil. Serum samples from 238 patients attending the Virology Sector of Evandro Chagas Institute in Belém, Brazil, were analyzed using microneutralization tests that included RD cells and BrCr strain. Overall 40.8% (97/238) of tested samples had NtAb to EV 71. Regarding the distribution per age group, 85.2% (92/108) of patients aged 0-3 years had no NtAb to this virus and 69.2% of those 12 to 15 years of age were seropositive. These results confirm that EV 71 infection occurs in the city of Belém; and that a high rate of individuals in this study were infected aged 3 years and over and, when aged 15 years nearly 70% had EV 71 NtAb. PMID:11992146

Gomes, Maria de Lourdes C; de Castro, Ceyla Maria O; Oliveira, Maria José C; da Silva, Edson Elias

2002-01-01

68

Multiplex RT-PCR in the diagnosis of human picornaviruses and human respiratory viruses.  

E-print Network

??The family Picornaviridae includes many human pathogens. Human enteroviruses (HEVs) exhibit a variety of clinical manifestations ranging from poliomyelitis and encephalomyelitis to respiratory infections and… (more)

Jokela, Pia

2012-01-01

69

Antiviral activity of Isatis indigotica root-derived clemastanin B against human and avian influenza A and B viruses in vitro.  

PubMed

Clemastanin B, 7S,8R,8'R-(-)-lariciresinol-4,4'-bis-O-?-D-glucopyranoside, is one of the major lignans extracted from Isatis indigotica root (IIR). In this study, the anti-influenza activities of clemastanin B were evaluated in vitro. Clemastanin B was found to inhibit different subtypes of human (H1N1, including swine-origin H1N1; H3N2 and influenza B) and avian influenza viruses (H6N2, H7N3, H9N2) at different magnitudes of activity (IC50 0.087-0.72 mg/ml) while this compound was inactive against respiratory syncytial virus (RSV), adenovirus 3 (ADV3), parainfluenza virus 3 (PIV3), enterovirus 71 (EV71) and human rhinovirus (HRV). An apparent virus titer reduction was detected when MDCK cells were treated with clemastanin B after viral infection, particularly at the early stage, and the ribonucleoprotein (RNP) of the influenza virus was retained in the nucleus after treatment with clemastanin B. These results demonstrated that clemastanin B targets viral endocytosis, uncoating or RNP export from the nucleus. Furthermore, treatment with clemastanin B did not easily result in the emergence of viral drug resistance. The effects of clemastanin B demonstrated in this study may promote the antiviral study of IIR, but additional studies are required to define the anti-influenza mechanism(s). PMID:23403777

Yang, Zifeng; Wang, Yutao; Zheng, Zhaoguang; Zhao, Suishan; Zhao, Jin; Lin, Qing; Li, Chuyuan; Zhu, Quan; Zhong, Nanshan

2013-04-01

70

Discovery of a Bovine Enterovirus in Alpaca  

PubMed Central

A cytopathic virus was isolated using Madin-Darby bovine kidney (MDBK) cells from lung tissue of alpaca that died of a severe respiratory infection. To identify the virus, the infected cell culture supernatant was enriched for virus particles and a generic, PCR-based method was used to amplify potential viral sequences. Genomic sequence data of the alpaca isolate was obtained and compared with sequences of known viruses. The new alpaca virus sequence was most similar to recently designated Enterovirus species F, previously bovine enterovirus (BEVs), viruses that are globally prevalent in cattle, although they appear not to cause significant disease. Because bovine enteroviruses have not been previously reported in U.S. alpaca, we suspect that this type of infection is fairly rare, and in this case appeared not to spread beyond the original outbreak. The capsid sequence of the detected virus had greatest homology to Enterovirus F type 1 (indicating that the virus should be considered a member of serotype 1), but the virus had greater homology in 2A protease sequence to type 3, suggesting that it may have been a recombinant. Identifying pathogens that infect a new host species for the first time can be challenging. As the disease in a new host species may be quite different from that in the original or natural host, the pathogen may not be suspected based on the clinical presentation, delaying diagnosis. Although this virus replicated in MDBK cells, existing standard culture and molecular methods could not identify it. In this case, a highly sensitive generic PCR-based pathogen-detection method was used to identify this pathogen. PMID:23950875

McClenahan, Shasta D.; Scherba, Gail; Borst, Luke; Fredrickson, Richard L.; Krause, Philip R.; Uhlenhaut, Christine

2013-01-01

71

Enterovirus Capsid Interactions with Decay-Accelerating Factor Mediate Lytic Cell Infection  

Microsoft Academic Search

The cellular receptor usage of numerous human enteroviruses can differ significantly between low-cell- culture-passaged clinical isolates and highly laboratory-passaged prototype strains. The prototype strain of coxsackievirus A21 (CVA21) displays a dual-receptor specificity as determined with a receptor complex consisting of decay-accelerating factor (DAF) and intercellular adhesion molecule 1 (ICAM-1). In this study, the cellular receptor interactions of low-cell-passage CVA21 clinical

Nicole G. Newcombe; E. Susanne Johansson; Gough Au; A. Michael Lindberg; Richard D. Barry; Darren R. Shafren

2004-01-01

72

Enter at Your Own Risk: How Enteroviruses Navigate the Dangerous World of Pattern Recognition Receptor Signaling  

PubMed Central

Enteroviruses are the most common human viral pathogens worldwide. This genus of small, non-enveloped, single stranded RNA viruses includes coxsackievirus, rhinovirus, echovirus, and poliovirus species. Infection with these viruses can induce mild symptoms that resemble the common cold, but can also be associated with more severe syndromes such as poliomyelitis, neurological diseases including aseptic meningitis and encephalitis, myocarditis, and the onset of type I diabetes. In humans, polarized epithelial cells lining the respiratory and/or digestive tracts represent the initial sites of infection by enteroviruses. Control of infection in the host is initiated through the engagement of a variety of pattern recognition receptors (PRRs). PRRs act as the sentinels of the innate immune system and serve to alert the host to the presence of a viral invader. This review assembles the available data annotating the role of PRRs in the response to enteroviral infection as well as the myriad ways by which enteroviruses both interrupt and manipulate PRR signaling to enhance their own replication, thereby inducing human disease. PMID:23764548

Harris, Katharine G; Coyne, Carolyn B

2013-01-01

73

INFECTIVITY AND PATHOGENICITY OF ENTEROVIRUSES INGESTED WITH DRINKING WATER  

EPA Science Inventory

The study was designed to examine the relationship of waterborne enteroviruses to infections and disease. Young weanling swine and their homologous enteroviruses were chosen as the model system: The porcine digestive tract is like that of man, but pigs can be handled under more c...

74

Genetic diversity and C2-like subgenogroup strains of enterovirus 71, Taiwan, 2008  

PubMed Central

Background Human enterovirus 71 (EV-71) is known of having caused numerous outbreaks of hand-foot-mouth disease, and other clinical manifestations globally. In 2008, 989 EV-71 strains were isolated in Taiwan. Results In this study, the genetic and antigenic properties of these strains were analyzed and the genetic diversity of EV-71 subgenogroups surfacing in Taiwan was depicted, which includes 3 previously reported subgenogroups of C5, B5, and C4, and one C2-like subgenogroup. Based on the phylogenetic analyses using their complete genome nucleotide sequences and neutralization tests, the C2-like subgenogroup forms a genetically distinct cluster from other subgenogroups, and the antisera show a maximum of 128-fold decrease of neutralization titer against this subgenogroup. In addition, the subgenogroup C4 isolates of 2008 were found quite similar genetically to the Chinese strains that caused outbreaks in recent years and thus they should be carefully watched. Conclusions Other than to be the first report describing the existence of C2-like subgenogroup of EV-71 in Taiwan, this article also foresees a potential of subgenogroup C4 outbreaks in Taiwan in the near future. PMID:20959020

2010-01-01

75

Pathogenic parasites and enteroviruses in wastewater: support for a regulation on water reuse.  

PubMed

Brazilian regulations for nonpotable reuse are being established using World Health Organization guidelines, however, they should be developed based on local monitoring studies. This study intended to analyze enteroviruses, protozoa and viable Ascaris sp. eggs in raw (24) and treated (24) effluents from four Wastewater Treatment Plants of São Paulo State, Brazil. The protozoa were detected with the US Environmental Protection Agency (USEPA) Method 1623 in the treated effluents and by centrifugation/Immunomagnetic Separation in the raw influent samples. Viable Ascaris sp. eggs were analyzed according to a modified USEPA method. Enteroviruses were quantified by using human rhabdomyosarcoma cells after adequate concentration procedures. All wastewater influents were positive for Giardia sp. whereas Cryptosporidium sp. was detected in 58.3% of the samples. Giardia sp. and Cryptosporidium sp. were present in 79.2 and 25.0% respectively, of the treated wastewater samples. Viable Ascaris sp. eggs were detected in 50.0 and 12.5% of influent and treated wastewater samples. Enteroviruses were isolated in the 24 raw influent samples and in 46% of the treated samples. Taking into account the densities of Giardia sp. in some treated wastewaters intended to be used as reclaimed water, Quantitative Microbial Risk Assessment studies should be conducted to establish pathogen quantitative criteria for a future Brazilian regulation for water reuse. PMID:23552239

Hachich, Elayse M; Galvani, Ana T; Padula, Jose A; Stoppe, Nancy C; Garcia, Suzi C; Bonanno, Vilma M S; Barbosa, Mikaela R F; Sato, Maria Inês Z

2013-01-01

76

Animal models of enterovirus 71 infection: applications and limitations.  

PubMed

Human enterovirus 71 (EV71) has emerged as a neuroinvasive virus that is responsible for several outbreaks in the Asia-Pacific region over the past 15 years. Appropriate animal models are needed to understand EV71 neuropathogenesis better and to facilitate the development of effective vaccines and drugs. Non-human primate models have been used to characterize and evaluate the neurovirulence of EV71 after the early outbreaks in late 1990s. However, these models were not suitable for assessing the neurovirulence level of the virus and were associated with ethical and economic difficulties in terms of broad application. Several strategies have been applied to develop mouse models of EV71 infection, including strategies that employ virus adaption and immunodeficient hosts. Although these mouse models do not closely mimic human disease, they have been applied to determine the pathogenesis of and treatment and prevention of the disease. EV71 receptor-transgenic mouse models have recently been developed and have significantly advanced our understanding of the biological features of the virus and the host-parasite interactions. Overall, each of these models has advantages and disadvantages, and these models are differentially suited for studies of EV71 pathogenesis and/or the pre-clinical testing of antiviral drugs and vaccines. In this paper, we review the characteristics, applications and limitation of these EV71 animal models, including non-human primate and mouse models. PMID:24742252

Wang, Ya-Fang; Yu, Chun-Keung

2014-01-01

77

Detection, quantitation and identification of enteroviruses from surface waters and sponge tissue from the Florida Keys using real-time RT-PCR.  

PubMed

A method was developed for the quantitative detection of pathogenic human enteroviruses from surface waters in the Florida Keys using Taqman (R) one-step Reverse transcription (RT)-PCR with the Model 7700 ABI Prism (R) Sequence Detection System. Viruses were directly extracted from unconcentrated grab samples of seawater, from seawater concentrated by vortex flow filtration using a 100 kD filter and from sponge tissue. Total RNA was extracted from the samples, purified and concentrated using spin-column chromatography. A 192-196 base pair portion of the 5' untranscribed region was amplified from these extracts. Enterovirus concentrations were estimated using real-time RT-PCR technology. Nine of 15 sample sites or 60% were positive for the presence of pathogenic human enteroviruses. Considering only near-shore sites, 69% were positive with viral concentrations ranging from 9.3 viruses/ml to 83 viruses/g of sponge tissue (uncorrected for extraction efficiency). Certain amplicons were selected for cloning and sequencing for identification. Three strains of waterborne enteroviruses were identified as Coxsackievirus A9, Coxsackievirus A16, and Poliovirus Sabin type 1. Time and cost efficiency of this one-step real-time RT-PCR methodology makes this an ideal technique to detect, quantitate and identify pathogenic enteroviruses in recreational waters. PMID:12153016

Donaldson, K A; Griffin, D W; Paul, J H

2002-05-01

78

Detection, quantitation and identification of enteroviruses from surface waters and sponge tissue from the Florida Keys using real-time RT-PCR  

USGS Publications Warehouse

A method was developed for the quantitative detection of pathogenic human enteroviruses from surface waters in the Florida Keys using Taqman (R) one-step Reverse transcription (RT)-PCR with the Model 7700 ABI Prism (R) Sequence Detection System. Viruses were directly extracted from unconcentrated grab samples of seawater, from seawater concentrated by vortex flow filtration using a 100kD filter and from sponge tissue. Total RNA was extracted from the samples, purified and concentrated using spin-column chromatography. A 192-196 base pair portion of the 5??? untranscribed region was amplified from these extracts. Enterovirus concentrations were estimated using real-time RT-PCR technology. Nine of 15 sample sites or 60% were positive for the presence of pathogenic human enteroviruses. Considering only near-shore sites, 69% were positive with viral concentrations ranging from 9.3viruses/ml to 83viruses/g of sponge tissue (uncorrected for extraction efficiency). Certain amplicons were selected for cloning and sequencing for identification. Three strains of waterborne enteroviruses were identified as Coxsackievirus A9, Coxsackievirus A16, and Poliovirus Sabin type 1. Time and cost efficiency of this one-step real-time RT-PCR methodology makes this an ideal technique to detect, quantitate and identify pathogenic enteroviruses in recreational waters. Copyright ?? 2002 Elsevier Science Ltd.

Donaldson, K.A.; Griffin, Dale W.; Paul, J.H.

2002-01-01

79

Site-specific targeting of enterovirus capsid by functionalized monodisperse gold nanoclusters  

PubMed Central

Development of precise protocols for accurate site-specific conjugation of monodisperse inorganic nanoparticles to biological material is one of the challenges in contemporary bionanoscience and nanomedicine. We report here a successful site-specific covalent conjugation of functionalized atomically monodisperse gold clusters with 1.5-nm metal cores to viral surfaces. Water-soluble Au102(para-mercaptobenzoic acid)44 clusters, functionalized by maleimide linkers to target cysteines of viral capsid proteins, were synthesized and conjugated to enteroviruses echovirus 1 and coxsackievirus B3. Quantitative analysis of transmission electron microscopy images and the known virus structures showed high affinity and mutual ordering of the bound gold clusters on the viral surface and a clear correlation between the clusters and the targeted cysteine sites close to the viral surface. Infectivity of the viruses was not compromised by loading of several tens of gold clusters per virus. These advances allow for future investigations of the structure?function relations of enteroviruses and enterovirus-related virus-like particles, including their entry mechanisms into cells and uncoating in cellular endosomes. PMID:24474748

Marjomäki, Varpu; Lahtinen, Tanja; Martikainen, Mari; Koivisto, Jaakko; Malola, Sami; Salorinne, Kirsi; Pettersson, Mika; Häkkinen, Hannu

2014-01-01

80

Quinacrine Impairs Enterovirus 71 RNA Replication by Preventing Binding of Polypyrimidine-Tract Binding Protein with Internal Ribosome Entry Sites  

PubMed Central

Since the 1980s, epidemics of enterovirus 71 (EV71) and other enteroviruses have occurred in Asian countries and regions, causing a wide range of human diseases. No effective therapy is available for the treatment of these infections. Internal ribosome entry sites (IRESs) are indispensable for the initiation of translation in enteroviruses. Several cellular factors, as well as the ribosome, are recruited to the conserved IRES during this process. Quinacrine intercalates into the RNA architecture and inhibits RNA transcription and protein synthesis, and a recent study showed that quinacrine inhibited encephalomyocarditis virus and poliovirus IRES-mediated translation in vitro without disrupting internal cellular IRES. Here, we report that quinacrine was highly active against EV71, protecting cells from EV71 infection. Replication of viral RNA, expression of viral capsid protein, and production of virus were all strongly inhibited by quinacrine. Interaction of the polypyrimidine tract-binding protein (PTB) with the conserved IRES was prevented by quinacrine. Coxsackieviruses and echovirus were also inhibited by quinacrine in cultured cells. These results indicate that quinacrine may serve as a potential protective agent for use in the treatment of patients with chronic enterovirus infection. PMID:23301007

Wang, Jianmin; Du, Jiang; Wu, Zhiqiang; Jin, Qi

2013-01-01

81

Clinical severity of rhinovirus/enterovirus compared to other respiratory viruses in children  

PubMed Central

Background Human rhinovirus/enterovirus (HRV/ENT) infections are commonly identified in children with acute respiratory infections (ARIs), but data on their clinical severity remain limited. Objectives We compared the clinical severity of HRV/ENT to respiratory syncytial virus (RSV), influenza A/B (FLU), and other common respiratory viruses in children. Patients/Methods Retrospective study of children with ARIs and confirmed single positive viral infections on mid-turbinate swabs by molecular assays. Outcome measures included hospital admission and, for inpatients, a composite endpoint consisting of intensive care admission, hospitalization >5 days, oxygen requirements or death. Results A total of 116 HRV/ENT, 102 RSV, 99 FLU, and 64 other common respiratory viruses were identified. Children with single HRV/ENT infections presented with significantly higher rates of underlying immunosuppressive conditions compared to those with RSV (37·9% versus 13·6%; P < 0·001), FLU (37·9% versus 22%; P = 0·018) or any other single viral infection (37·9% versus 22·5%; P = 0·024). In multivariable analysis adjusted for underlying conditions and age, children with HRV/ENT infections had increased odds of hospitalization compared to children with RSV infections (OR 2·6; 95% CI 1·4, 4·8; P < 0·003) or FLU infections (OR 3·0; 95% CI 1·6, 5·8; <0·001) and increased odds of severe clinical disease among inpatients (OR 3·0; 95% CI 1·6,5·6; P = 0·001) when compared to those with FLU infections. Conclusions Children with HRV/ENT had a more severe clinical course than those with RSV and FLUA/B infections and often had significant comorbidities. These findings emphasize the importance of considering HRV/ENT infection in children presenting with severe acute respiratory tract infections. PMID:24801963

Asner, Sandra A; Petrich, Astrid; Hamid, Jemila S; Mertz, Dominik; Richardson, Susan E; Smieja, Marek

2014-01-01

82

Inhibition of enterovirus 71 by adenosine analog NITD008.  

PubMed

Enterovirus 71 (EV71) is a major viral pathogen in China and Southeast Asia. There is no clinically approved vaccine or antiviral therapy for EV71 infection. NITD008, an adenosine analog, is an inhibitor of flavivirus that blocks viral RNA synthesis. Here we report that NITD008 has potent antiviral activity against EV71. In cell culture, the compound inhibits EV71 at a 50% effective concentration of 0.67 ?M and a 50% cytotoxic concentration of 119.97 ?M. When administered at 5 mg/kg in an EV71 mouse model, the compound reduced viral loads in various organs and completely prevented clinical symptoms and death. To study the antiviral mechanism and drug resistance, we selected escape mutant viruses by culturing EV71 with increasing concentrations of NITD008. Resistance mutations were reproducibly mapped to the viral 3A and 3D polymerase regions. Resistance analysis with recombinant viruses demonstrated that either a 3A or a 3D mutation alone could lead to resistance to NITD008. A combination of both 3A and 3D mutations conferred higher resistance, suggesting a collaborative interplay between the 3A and 3D proteins during viral replication. The resistance results underline the importance of combination therapy required for EV71 treatment. Importance: Human enterovirus 71 (EV71) has emerged as a major cause of viral encephalitis in children worldwide, especially in the Asia-Pacific region. Vaccines and antivirals are urgently needed to prevent and treat EV71 infections. In this study, we report the in vitro and in vivo efficacy of NITD008 (an adenosine analog) as an inhibitor of EV71. The efficacy results validated the potential of nucleoside analogs as antiviral drugs for EV71 infections. Mechanistically, we showed that mutations in the viral 3A and 3D polymerases alone or in combination could confer resistance to NITD008. The resistance results suggest an intrinsic interaction between viral proteins 3A and 3D during replication, as well as the importance of combination therapy for the treatment of EV71 infections. PMID:25100827

Deng, Cheng-Lin; Yeo, Huimin; Ye, Han-Qing; Liu, Si-Qing; Shang, Bao-Di; Gong, Peng; Alonso, Sylvie; Shi, Pei-Yong; Zhang, Bo

2014-10-01

83

Clinical manifestations of CNS infections caused by enterovirus type 71  

PubMed Central

Purpose Enterovirus 71, one of the enteroviruses that are responsible for both hand-foot-and-mouth disease and herpangina, can cause neural injury. During periods of endemic spread of hand-foot-andmouth disease caused by enterovirus 71, CNS infections are also frequently diagnosed and may lead to increased complications from neural injury, as well as death. We present the results of our epidemiologic research on the clinical manifestations of children with CNS infections caused by enterovirus 71. Methods The study group consisted of 42 patients admitted for CNS infection by enterovirus 71 between April 2009 and October 2009 at the Department of Pediatrics of 5 major hospitals affiliated with the Catholic University of Korea. We retrospectively reviewed initial symptoms and laboratory findings on admission, the specimen from which enterovirus 71 was isolated, fever duration, admission period, treatment and progress, and complications. We compared aseptic meningitis patients with encephalitis patients. Results Of the 42 patients (23 men, 19 women), hand-foot-and-mouth disease was most prevalent (n=39), followed by herpangina (n=3), upon initial clinical diagnosis. Among the 42 patients, 15 (35.7%) were classified as severe, while 27 (64.3%) were classified as mild. Factors such as age, fever duration, presence of seizure, and use of intravenous immunoglobulin (IVIG) were statistically different between the 2 groups. Conclusion Our results indicate that patients with severe infection caused by enterovirus 71 tended to be less than 3 years old, presented with at least 3 days of fever as well as seizure activity, and received IVIG treatment. PMID:21359055

Choi, Cheol Soon; Choi, Yun Jung; Choi, Ui Yoon; Han, Ji Whan; Jeong, Dae Chul; Kim, Hyun Hee; Kim, Jong Hyun

2011-01-01

84

Tissue tropism, pathology and pathogenesis of enterovirus infection.  

PubMed

Enteroviruses are very common and cause infections with a diverse array of clinical features. Enteroviruses are most frequently considered by practising pathologists in cases of aseptic meningitis, encephalitis, myocarditis and disseminated infections in neonates and infants. Congenital infections have been reported and transplacental transmission is thought to occur. Although skin biopsies during hand, foot and mouth disease are infrequently obtained, characteristic dermatopathological findings can be seen. Enteroviruses have been implicated in lower respiratory tract infections. This review highlights histopathological features of enterovirus infection and discusses diagnostic modalities for formalin-fixed paraffin-embedded tissues and their associated pitfalls. Immunohistochemistry can detect enterovirus antigen within cells of affected tissues; however, assays can be non-specific and detect other viruses. Molecular methods are increasingly relied upon but, due to the high frequency of asymptomatic enteroviral infections, clinical-pathological correlation is needed to determine significance. Of note, diagnostic assays on central nervous system or cardiac tissues from immunocompetent patients with prolonged disease courses are most often negative. Histopathological, immunohistochemical and molecular studies performed on clinical specimens also provide insight into enteroviral tissue tropism and pathogenesis. Published 2014. This article is a U.S. Government work and is in the public domain in the USA. PMID:25211036

Muehlenbachs, Atis; Bhatnagar, Julu; Zaki, Sherif R

2015-01-01

85

Effect of enteroviruses on adherence to and invasion of HEp-2 cells by Campylobacter isolates.  

PubMed Central

Coinfection of HEp-2 epithelial cells with coxsackievirus B3, echovirus 7, poliovirus (LSc type 1), porcine enterovirus, and Campylobacter isolates was performed to determine if a synergistic effect could be obtained. The invasiveness of Campylobacter jejuni ATCC 33560 was significantly increased for HEp-2 cells preinfected with echovirus 7, coxsackievirus B3, and UV-inactivated (noninfectious) coxsackievirus B3 particles. Additionally, the invasiveness of C. jejuni M96, a clinical isolate, was significantly increased for HEp-2 cells preinfected with coxsackievirus B3. Poliovirus and porcine enterovirus had no effect on C. jejuni ATCC 33560 adherence and invasiveness. Furthermore, poliovirus had no effect on the ability of C. jejuni M96 to adhere to and invade HEp-2 cells. Campylobacter hyointestinalis and Campylobacter mucosalis, two noninvasive isolates, did not invade virus-infected HEp-2 cells. The increase in the invasiveness of C. jejuni appeared to be the result of specific interactions between the virus and the HEp-2 cell membrane. The data suggest that the invasiveness of Campylobacter spp. is dependent upon the inherent properties of the organism. Virus-induced cell alterations can potentiate the invasiveness of virulent Campylobacter spp. but are not sufficient to allow internalization of noninvasive bacteria. PMID:2156779

Konkel, M E; Joens, L A

1990-01-01

86

Pathological examinations of an enterovirus 71 infection: an autopsy case  

PubMed Central

We report an 8-month-old female infant with the fatal enterovirus 71 infection here. Clinically, she developed respiratory failure and severe pulmonary edema rapidly. Histologically, the lung specimen showed diffuse, severe pulmonary congestion and edema with focal intra-alveolar hemorrhage and typical features of acute encephalitis were easily identified under light microscope. Immunohistochemically, enterovirus 71 antigen was positive in the cerebella and brainstem. We measured the viral loads of different tissues and found that the brainstem and mesenteric lymph nodes showed the highest viral loads among all tissues. We hope that our case report may help to have a better understanding of the enterovirus 71 infection and provide clues to the prevention and treatment of this disease. PMID:25197403

Gao, Lulu; Lin, Peixin; Liu, Shuguang; Lei, Bin; Chen, Qing; Yu, Shouyi; Shen, Hong

2014-01-01

87

Short Communication: New Recognition Of Enterovirus Infections In Bottlenose Dolphins (Tursiops Truncatus)  

PubMed Central

An enterovirus was cultured from an erosive tongue lesion of a bottlenose dolphin (Tursiops truncatus). The morphology of virions on negative staining electron microscopy was consistent with those of enteroviruses. Analysis of 2613 bp of the polyprotein gene identified the isolate as a novel enterovirus strain, tentatively named bottlenose dolphin enterovirus (BDEV), that nests within the species Bovine enterovirus. Serologic evidence of exposure to enteroviruses was common in both free ranging and managed collection dolphins. Managed collection dolphins were more likely to have high antibody levels, although the highest levels were reported in free ranging populations. Associations between enterovirus antibody levels, and age, sex, complete blood counts, and clinical serum biochemistries were explored. Dolphins with higher antibody levels were more likely to be hyperproteinemic and hyperglobulinemic. PMID:19581059

Nollens, Hendrik H.; Rivera, Rebecca; Palacios, Gustavo; Wellehan, James F. X.; Saliki, Jeremiah T.; Caseltine, Shannon L.; Smith, Cynthia R.; Jensen, Eric D.; Hui, Jeffrey; Lipkin, W. Ian; Yochem, Pamela K.; Wells, Randall S.; St. Leger, Judy; Venn-Watson, Stephanie

2014-01-01

88

Enterovirus 71 blocks selectively type I interferon production through the 3C viral protein in mice.  

PubMed

Type I interferons (IFNs) represent an essential innate defense mechanism for controlling enterovirus 71 (EV 71) infection. Mice inoculated with EV 71 produced a significantly lower amount of type I IFNs than those inoculated with poly (I:C), adenovirus type V, or coxsackievirus B3 (CB3). EV 71 infection, however, mounted a proinflammatory response with a significant increase in the levels of serum and brain interleukin (IL)-6, monocyte chemoattractant protein-1, tumor necrosis factor, and IFN-?. EV 71 infection abolished both poly (I:C)- and CB3-induced type I IFN production of mice. Such effect was not extended to other enteroviruses including coxsackievirus A24, B2, B3, and echovirus 9, as mice infected with these viruses retained type I IFN responsiveness upon poly (I:C) challenge. In addition, EV 71-infected RAW264.7 cells produced significantly lower amount of type I IFNs than non-infected cells upon poly (I:C) stimulation. The inhibitory effect of EV 71 on type I IFN production was attributed to the viral protein 3C, which was confirmed using over-expression systems in both mice and RAW264.7 cells. The 3C over-expression, however, did not interfere with poly (I:C)-induced proinflammatory cytokine production. These findings indicate that EV 71 can hamper the host innate defense by blocking selectively type I IFN synthesis through the 3C viral protein. PMID:22997081

Lee, Yi-Ping; Wang, Ya-Fang; Wang, Jen-Ren; Huang, Szu-Wei; Yu, Chun-Keung

2012-11-01

89

Characterization of Human Papillomavirus Subtype 72b  

PubMed Central

We report the characterization of human papillomavirus (HPV) subtype 72b of the genus Alphapapillomavirus isolated from an oral rinse sample of a healthy woman. The HPV72b L1 open reading frame (ORF) was 90.2% identical to that of HPV72, indicating a subtype close to the border of a novel HPV type. PMID:25523776

Johansson, Hanna; Kravtchenko, Evgenia

2014-01-01

90

Detection of enteroviruses in untreated and treated drinking water supplies in South Africa.  

PubMed

Enteric viruses have been detected in many drinking water supplies all over the world. A meaningful number of these supplies were treated and disinfected according to internationally acceptable methods. In addition, counts of bacterial indicators (coliform bacteria and heterotrophic plate count organisms) in these water supplies were within limits generally recommended for treated drinking water and these findings have been supported by epidemiological data on infections associated with drinking water. The shortcomings of conventional treatment methods and indicator organisms to confirm the absence of enteric viruses from drinking water, was generally ascribed to the exceptional resistance of these viruses. In this study, the prevalence of enteroviruses detected from July 2000 to June 2002 in sewage, river-, borehole-, spring- and dam water as well as drinking water supplies treated and disinfected according to international specifications for the production of safe drinking water was analysed. A glass wool adsorption-elution technique was used to recover viruses from 10--20 l of sewage as well as environmental water samples, in the case of drinking water from more than 100 l. Recovered enteroviruses were inoculated onto two cell culture types (BGM and PLC/PRF/5 cells) for amplification of viral RNA with nested-PCR being used to detect the amplified viral RNA. Results from the study demonstrated the presence of enteroviruses in 42.5% of sewage and in 18.7% of treated drinking water samples. Furthermore, enteroviruses were detected in 28.5% of river water, in 26.7% of dam/spring water and in 25.3% of borehole water samples. The high prevalence of coxsackie B viruses found in this study suggested, that a potential health risk and a burden of disease constituted by these viruses might be meaningful. These findings indicated that strategies, other than end-point analysis of treated and disinfected drinking water supplies, may be required to ensure the production of drinking water that does not exceed acceptable health risks. More reliable approaches to ensure acceptable safety of drinking water supplies may be based on control by multiple-barrier principles from catchment to tap using hazard assessment and critical control point (HACCP) principles. PMID:15919105

Ehlers, M M; Grabow, W O K; Pavlov, D N

2005-06-01

91

Team 2: Human Resources 2.B Human Resources (Leist/Defa)  

E-print Network

Team 2: Human Resources Areas: · 2.B Human Resources (Leist/Defa) · Policies and Procedures: Human. Policies and Procedures Human Resources 2.A.18 The institution maintains and publishes its human resources of human resources records. 2.B ­ Human Resources 2.B.1 The institution employs a sufficient number

Lawrence, Rick L.

92

Host factors in enterovirus 71 replication.  

PubMed

Enterovirus 71 (EV71) infections continue to remain an important public health problem around the world, especially in the Asia-Pacific region. There is a significant mortality rate following such infections, and there is neither any proven therapy nor a vaccine for EV71. This has spurred much fundamental research into the replication of the virus. In this review, we discuss recent work identifying host cell factors which regulate the synthesis of EV71 RNA and proteins. Three of these proteins, heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1), far-upstream element-binding protein 2 (FBP2), and FBP1 are nuclear proteins which in EV71-infected cells are relocalized to the cytoplasm, and they influence EV71 internal ribosome entry site (IRES) activity. hnRNP A1 stimulates IRES activity but can be replaced by hnRNP A2. FBP2 is a negative regulatory factor with respect to EV71 IRES activity, whereas FBP1 has the opposite effect. Two other proteins, hnRNP K and reticulon 3, are required for the efficient synthesis of viral RNA. The cleavage stimulation factor 64K subunit (CstF-64) is a host protein that is involved in the 3' polyadenylation of cellular pre-mRNAs, and recent work suggests that in EV71-infected cells, it may be cleaved by the EV71 3C protease. Such a cleavage would impair the processing of pre-mRNA to mature mRNAs. Host cell proteins play an important role in the replication of EV71, but much work remains to be done in order to understand how they act. PMID:21715481

Shih, Shin-Ru; Stollar, Victor; Li, Mei-Ling

2011-10-01

93

Host Factors in Enterovirus 71 Replication ?  

PubMed Central

Enterovirus 71 (EV71) infections continue to remain an important public health problem around the world, especially in the Asia-Pacific region. There is a significant mortality rate following such infections, and there is neither any proven therapy nor a vaccine for EV71. This has spurred much fundamental research into the replication of the virus. In this review, we discuss recent work identifying host cell factors which regulate the synthesis of EV71 RNA and proteins. Three of these proteins, heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1), far-upstream element-binding protein 2 (FBP2), and FBP1 are nuclear proteins which in EV71-infected cells are relocalized to the cytoplasm, and they influence EV71 internal ribosome entry site (IRES) activity. hnRNP A1 stimulates IRES activity but can be replaced by hnRNP A2. FBP2 is a negative regulatory factor with respect to EV71 IRES activity, whereas FBP1 has the opposite effect. Two other proteins, hnRNP K and reticulon 3, are required for the efficient synthesis of viral RNA. The cleavage stimulation factor 64K subunit (CstF-64) is a host protein that is involved in the 3? polyadenylation of cellular pre-mRNAs, and recent work suggests that in EV71-infected cells, it may be cleaved by the EV71 3C protease. Such a cleavage would impair the processing of pre-mRNA to mature mRNAs. Host cell proteins play an important role in the replication of EV71, but much work remains to be done in order to understand how they act. PMID:21715481

Shih, Shin-Ru; Stollar, Victor; Li, Mei-Ling

2011-01-01

94

ENTEROVIRUSES IN SLUDGE: MULTIYEAR EXPERIENCE WITH FOUR WASTEWATER TREATMENT PLANTS  

EPA Science Inventory

The authors describe their experience with the isolation of viruses from four treatment plants located in different geographic areas. Over a period of 3 years, 297 enteroviruses were isolated from 307 sludge samples. The highest frequency of viral isolation (92%), including multi...

95

Elicitation of T-cell responses by structural and non-structural proteins of coxsackievirus B4.  

PubMed

Coxsackievirus B4 (CV-B4) belongs to the genus Enterovirus within the family Picornaviridae. To investigate target proteins recognized by T-cells in human enterovirus B infections, virus-encoded structural [VP0 (VP4 and VP2), VP1, VP3] and non-structural (2A, 2B, 2C, 3C and 3D) proteins were expressed and purified in Escherichia coli. Peripheral blood of 19 healthy adult donors was used to create enterovirus-specific T-cell lines by repeated stimulation with CV-B4 cell lysate antigen. T-cell lines responded in individual patterns, and responses to all purified proteins were observed. The most often recognized enteroviral protein was VP0, which is the fusion between the most conserved structural proteins, VP4 and VP2. T-cell responses to VP0 were detected in 15 of the 19 (79?%) donor lines. Non-structural 2C protein was recognized in 11 of the 19 (58?%) lines, and 11 of the 19 (58?%) lines also had a response to 3D protein. Furthermore, responses to other non-structural proteins (2A, 2B and 3C) were also detected. T-cell responses did not correlate clearly to the individual HLA-DR-DQ phenotype or the history of past coxsackie B virus infections of the donors. PMID:25381056

Bengs, Suvi; Marttila, Jane; Susi, Petri; Ilonen, Jorma

2015-02-01

96

QDs Capped with Enterovirus As Imaging Probes for Drug Screening  

Microsoft Academic Search

The increasing threats of viral diseases have gained worldwide attention in recent years. Quite a few infectious diseases\\u000a are still lack of effective prevention or treatment. The pace of developing antiviral agents could be expedited by the availability\\u000a of quick and efficient drug screening platforms. Enterovirus 71 (EV71) is a highly infectious major causative agent of hand,\\u000a foot, and mouth

Chung-Hao Wang; Ching-An Peng

97

WNT10B mutations in human obesity  

PubMed Central

Aims/hypothesis Recent studies suggest that wingless-type MMTV integration site family, member 10B (WNT10B) may play a role in the negative regulation of adipocyte differentiation in vitro and in vivo. In order to determine whether mutations in WNT10B contribute to human obesity, we screened two independent populations of obese subjects for mutations in this gene. Subjects and methods We studied 96 subjects with severe obesity of early onset (less than 10 years of age) from the UK Genetics of Obesity Study and 115 obese Italian subjects of European origin. Results One proband with early-onset obesity was found to be heterozygous for a C256Y mutation, which abrogated the ability of WNT10B to activate canonical WNT signalling and block adipogenesis and was not found in 600 control alleles. All relatives of the proband who carried this allele were either overweight or obese. Three other rare missense variants were found in obese probands, but these did not clearly cosegregate with obesity in family studies and one (P301S), which was found in three unrelated subjects with early-onset obesity, had normal functional properties. Conclusions/interpretation These mutations represent the first naturally occurring missense variants of WNT10B. While the pedigree analysis in the case of C256Y WNT10B does not provide definitive proof of a causal link of this variant with obesity, the finding of a non-functioning WNT10B allele in a human family affected by obesity should encourage further study of this gene in other obese populations. PMID:16477437

Christodoulides, C.; Scarda, A.; Granzotto, M.; Milan, G.; Dalla Nora, E.; Keogh, J.; De Pergola, G.; Stirling, H.; Pannacciulli, N.; Sethi, J. K.; Federspil, G.; Vidal-Puig, A.; Farooqi, I. S.; O’Rahilly, S.; Vettor, R.

2015-01-01

98

Enterovirus 71 isolated from cases of epidemic poliomyelitis-like disease in Bulgaria  

Microsoft Academic Search

Summary Virological and serological studies of an epidemic disease in Bulgaria, 1975, were carried out. Epidemiologically, clinically and pathomorphologically, the disease simulated almost all known forms of poliomyelitis, acute stem encephalitis, encephalomyocarditis and aseptic meningitis. The studies completely ruled out the participation of polioviruses and provided comprehensive evidence for the etiological role of a peculiar enterovirus subsequently identified as enterovirus

M. Chumakov; M. VOROSttILOVA; L. Shindarov; I. Lavrova; L. Gracheva; G. Koroleva; S. Vasilenko; I. Brodvarova; M. Nikolova; S. Gyurova; M. Gacheva; G. Mitov; N. Ninov; E. Tsylka; I. Robinson; M. Frolova; V. Bashkirtsev; L. Martiyanova; V. Rodin

1979-01-01

99

Epidemic of Hand, Foot and Mouth Disease Associated with Enterovirus 71 Infection  

Microsoft Academic Search

Summary Viruses isolated from patients with hand, foot and mouth disease in widespread outbreaks in Japan in 1973 were identified as enterovirus 71. Although cases with aseptic meningitis were observed concurrently, the main clinical symptom associated with enterovirus 71 infection was hand, foot and mouth disease.Copyright © 1978 S. Karger AG, Basel

Akio Hagiwara; Isamu Tagaya; Tetsuo Yoneyama

1978-01-01

100

Molecular Identification and Characterization of a New Type of Bovine Enterovirus  

PubMed Central

Bovine enteroviruses belong to the family Picornaviridae. Little is known about their pathogenic potential; however, they cause asymptomatic infections in cattle and are excreted in feces. In the present study, viruses isolated from environmental samples were sequenced. According to phylogenetic analyses and standard picornavirus nomenclature, these isolates constitute a new type of bovine enterovirus serogroup A. PMID:22492440

Shaukat, Shahzad; Angez, Mehar; Alam, Muhammad Masroor; Sharif, Salmaan; Khurshid, Adnan; Malik, Farzana; Rana, Muhammad Suleman; Mahmood, Tariq

2012-01-01

101

Inhibition of Enterovirus 71 (EV-71) Infections by a Novel Antiviral Peptide Derived from EV-71 Capsid Protein VP1  

PubMed Central

Enterovirus 71 (EV-71) is the main causative agent of hand, foot and mouth disease (HFMD). In recent years, EV-71 infections were reported to cause high fatalities and severe neurological complications in Asia. Currently, no effective antiviral or vaccine is available to treat or prevent EV-71 infection. In this study, we have discovered a synthetic peptide which could be developed as a potential antiviral for inhibition of EV-71. Ninety five synthetic peptides (15-mers) overlapping the entire EV-71 capsid protein, VP1, were chemically synthesized and tested for antiviral properties against EV-71 in human Rhabdomyosarcoma (RD) cells. One peptide, SP40, was found to significantly reduce cytopathic effects of all representative EV-71 strains from genotypes A, B and C tested, with IC50 values ranging from 6–9.3 µM in RD cells. The in vitro inhibitory effect of SP40 exhibited a dose dependent concentration corresponding to a decrease in infectious viral particles, total viral RNA and the levels of VP1 protein. The antiviral activity of SP40 peptide was not restricted to a specific cell line as inhibition of EV-71 was observed in RD, HeLa, HT-29 and Vero cells. Besides inhibition of EV-71, it also had antiviral activities against CV-A16 and poliovirus type 1 in cell culture. Mechanism of action studies suggested that the SP40 peptide was not virucidal but was able to block viral attachment to the RD cells. Substitutions of arginine and lysine residues with alanine in the SP40 peptide at positions R3A, R4A, K5A and R13A were found to significantly decrease antiviral activities, implying the importance of positively charged amino acids for the antiviral activities. The data demonstrated the potential and feasibility of SP40 as a broad spectrum antiviral agent against EV-71. PMID:22563456

Tan, Chee Wah; Chan, Yoke Fun; Sim, Kooi Mow; Tan, Eng Lee; Poh, Chit Laa

2012-01-01

102

Molecular epidemiology of echoviruses 11 and 30 in Russia: Different properties of genotypes within an enterovirus serotype.  

PubMed

Over 100 known enterovirus serotypes differ in their epidemiological and pathogenic properties. Much less is known about variation of these features on a sub-serotype level, such as genotypes. Echovirus 11 (E11) and E30 are amongst the most frequent causative agents of aseptic meningitis. We studied the molecular epidemiology of these pathogens to evaluate potential epidemiological and pathogenic dissimilarities of their genotypes. The complete VP1 genome region was sequenced for 97 E11 and 62 E30 isolates collected in Russia from 2008 to 2012, and they were studied in comparison with all 140 E11 and 432 E30 sequences available in GenBank. A geographic pattern of genotype prevalence was observed for both types. Russian E11 isolates belonged mainly to A genotype, which is common in Asia, and D5, which is predominant in Europe. For E30, genotype III by classification of Ke et al. (2011), also termed genotype a by Bailly et al. (2009), was endemic in Russia from 2003 to 2012, while it was not detected in Europe and North America during this time. The E30 genotypes VI-B, VI-G, and VI-H (e, f and h) were regularly introduced from different countries, became predominant and vanished after no more than 4years. In addition to geographic patterns, E11 genotypes also differed by isolation source. Genotype A2 viruses were significantly more often found in sewage, compared to genotype D5 that was isolated from both sewage and human samples. In addition, there was evidence of a different capacity for international transfers among E11 GtA subclusters. PMID:25562123

Yarmolskaya, Maria S; Shumilina, Elena Yu; Ivanova, Olga E; Drexler, Jan Felix; Lukashev, Alexander N

2015-03-01

103

Enterovirus infection in children attending two outpatient clinics in Zhejiang Province, China.  

PubMed

Enteroviruses are responsible for hand, foot, and mouth disease, and have caused many deaths in China during recent years. But the natural history of enterovirus infection in children, especially asymptomatic children, is not yet clear. From April 2011 to May 2012, 505 stool and throat swab samples of children attending outpatients clinics in two hospitals were collected weekly to test for Enterovirus 71, Coxsackievirus A16, and other enterovirus nucleic acids by real-time RT-PCR. Two hundred sixty-four patients were enterovirus positive, the positive rate was 52.3%, 27.5% (22/80) in children without a rash and 56.9% (242/425) in children with a rash. Coxsackievirus A16 positive rate of male (24%, 61/254) was higher than that of female (15.2%, 26/171) (?(2) ?=?4.87, P?=?0.027). The highest positive rate of enterovirus infection was 63.5% in the 2-year-old age group. Comparing children with and without a rash, within the same age groups, no statistical difference was found (P?>?0.05). The seasonal distribution of Enterovirus 71 had only one peak in May, but Coxsackievirus A16 had two peaks in April and October. In patients with a rash, the frequency of Enterovirus 71 was relatively high before July, and then that of Coxsackievirus A16 increased gradually. In the case of Enterovirus 71 and Coxsackievirus A16, stool specimens had a higher positive rate than throat swab specimens' (?(2) ?=?3.88, P?=?0.05; ?(2) ?=?15.13, P?Enterovirus infection was more frequent in males 2-3 year-old children, with the implicated virus varying by season. Targeted prevention and control measures should be carried out. PMID:24519430

Cai, Jian; Lv, Huakun; Lin, Junfen; Chen, Zhiping; Fang, Chunfu; Han, Jiankang

2014-09-01

104

UWMadison, Office of Human Resources Human Resource System B91002.20101229  

E-print Network

UW­Madison, Office of Human Resources Human Resource System B91002.20101229 State Group Health Information Submit completed checklist and attachments to: Office of Human Resources, Benefit Services, 21 N: __________________________________________________________________________________ ____________________________________________________________________________________________ ____________________________________________________________________________________________ mm/dd/yyyy mm/dd/yyyy #12;UW­Madison, Office of Human Resources Human Resource System B91002

Wisconsin at Madison, University of

105

Partial sequencing of the VP2 capsid gene for direct enterovirus genotyping in clinical specimens.  

PubMed

Typing of human enterovirus (EV) remains a major goal for diagnostic and epidemiological purposes. Whereas sequencing of the VP1 coding region is the reference standard for EV typing, a method relying on sequencing of the VP2 coding region has been proposed as an alternative; however, this has been validated only on cell culture supernatants. To avoid the selection of cultivable strains and to quicken the identification step, a new semi-nested PCR method targeting the VP2 region was developed by use of the CODEHOP strategy. After validation of the method on reference and clinical strains, a total of 352 clinical specimens found to be positive for EV RNA (138 with the GeneXpert EV kit and 214 with the Enterovirus R-gene kit) during a 3-year period (2010-2012) were analysed prospectively for VP2 genotyping. Overall, 204 (58%) specimens were typeable. A higher proportion of throat swab/stool specimens than of cerebrospinal fluid (CSF) specimens was found to be typeable (94 of 142 (66.2%) vs. 83 of 169 (49.1%), respectively, p <0.01 by the chi-square test). Moreover, the median Ct value obtained was lower for typeable specimens than for untypeable specimens (32.20 vs. 33.01, p <0.05, and 25.96 vs. 31.74, p <0.001, for the GeneXpert and R-gene tests, respectively, by the Mann-Whitney-Wilcoxon test). These results suggest that, in cases of EV meningitis, a peripheral specimen (i.e. throat swab or stool) that is susceptible to exhibiting a higher viral load should be used in preference to CSF for identifying the causative EV genotype by use of the VP2 typing method without cell culture isolation. PMID:24372815

Ibrahim, W; Boukhadra, N; Nasri-Zoghlami, D; Berthelot, P; Omar, S; Bourlet, T; Pozzetto, B; Pillet, S

2014-09-01

106

Replication strategy of human hepatitis B virus  

SciTech Connect

To study the replication strategy of the human hepatitis B virus, the 5' end of the RNA pregenome and the initiation sites of DNA plus and minus strands have been mapped. The RNA pregenome was found to be terminally redundant by 120 nucleotides; it is initiated within the pre-C region and may also function as mRNA for synthesis of the major core protein and the hepatitis B virus reverse transcriptase. The hepatitis B virus DNA minus strand is initiated within the direct repeat sequence DR1, it contains a terminal redundancy of up to eight nucleotides, and its synthesis does not require any template switch. The DNA plus strand is primed by a short oligoribonucleotide probably derived from the 5' end of the RNA pregenome, and its synthesis is initiated close to the direct repeat sequence DR2. For its elongation to pass the discontinuity in the DNA minus strand an intramolecular template switch occurs using the terminal redundancy of this template. Thus, the route of reverse transcription and DNA replication of hepatitis B viruses is fundamentally different from that of retroviruses.

Will, H.; Reiser, W.; Weimer, T.; Pfaff, E.; Buescher, M.; Sprengel, R.; Cattaneo, R.; Schaller, H.

1987-03-01

107

Human B cell defects in perspective  

PubMed Central

While primary immune defects are generally considered to lead to severe and easily recognized disease in infants and children, a number of genetic defects impairing B cell function may not be clinically apparent or diagnosed until adult life. The commonest of these is common variable immune deficiency, the genetic origins of which are beginning to be at least partially understood. CVID affects ? 1/25,000 Caucasians and is characterized by a marked reduction in serum IgG, almost always in serum IgA, and reduced serum IgM in about half of all cases; these defects continue to provide an opportunity to investigate the genes necessary for B cell function in humans. Recently, a small number of genes necessary for normal B cell function have been identified in consanguineous families leading to varying degrees of hypogammaglobulinemia and loss of antibody production. In other studies, whole-exome sequencing and copy number variation, applied to large cohorts, have extended research into understanding both the genetic basis of this syndrome and the clinical phenotypes of CVID. PMID:22477523

2012-01-01

108

Class I ADP-Ribosylation Factors Are Involved in Enterovirus 71 Replication  

PubMed Central

Enterovirus 71 is one of the major causative agents of hand, foot, and mouth disease in infants and children. Replication of enterovirus 71 depends on host cellular factors. The viral replication complex is formed in novel, cytoplasmic, vesicular compartments. It has not been elucidated which cellular pathways are hijacked by the virus to create these vesicles. Here, we investigated whether proteins associated with the cellular secretory pathway were involved in enterovirus 71 replication. We used a loss-of-function assay, based on small interfering RNA. We showed that enterovirus 71 RNA replication was dependent on the activity of Class I ADP-ribosylation factors. Simultaneous depletion of ADP-ribosylation factors 1 and 3, but not three others, inhibited viral replication in cells. We also demonstrated with various techniques that the brefeldin-A-sensitive guanidine nucleotide exchange factor, GBF1, was critically important for enterovirus 71 replication. Our results suggested that enterovirus 71 replication depended on GBF1-mediated activation of Class I ADP-ribosylation factors. These results revealed a connection between enterovirus 71 replication and the cellular secretory pathway; this pathway may represent a novel target for antiviral therapies. PMID:24911624

Wang, Jianmin; Du, Jiang; Jin, Qi

2014-01-01

109

Generation of Functional Human Pancreatic b Cells In Vitro  

E-print Network

and quality of donor islets (Bellin et al., 2012). The generation of an unlimited supply of human b cells fromResource Generation of Functional Human Pancreatic b Cells In Vitro Felicia W. Pagliuca,1,3 Jeffrey in diabetes. However, insu- lin-producing cells previously generated from human pluripotent stem cells (h

Blackwell, Keith

110

Human-Automation Interaction By Thomas B. Sheridan & Raja Parasuraman  

E-print Network

89 CHAPTER 2 Human-Automation Interaction By Thomas B. Sheridan & Raja Parasuraman Automation does not mean humans are replaced; quite the opposite. Increasingly, humans are asked to interact-free task for either the system designer or the human operator/automation supervisor, especially as computer

Parasuraman, Raja

111

A1B: balanced. Human vulnerability to heat  

E-print Network

A1B: balanced. Human vulnerability to heat can be define a function of heat exposure, sensitivity, and coping capacities. A better understanding of human vulnerability to heat can help people to decrease heat impact on human health effectively. Human vulnerability to heat in Phoenix and Chicago: Wen-Ching Chuang

Hall, Sharon J.

112

Mangrove forests and human security1 Bradley B. Walters*  

E-print Network

Review Mangrove forests and human security1 Bradley B. Walters* Address: Department of Geography of `environment and security' and examines their relevance in understanding human­mangrove interactions and human security. Research on human­mangrove interactions suggests that mangrove forests illustrate

Walters, Bradley B.

113

Enterovirus 71 can directly infect the brainstem via cranial nerves and infection can be ameliorated by passive immunization.  

PubMed

Enterovirus 71 (EV71)-associated hand, foot, and mouth disease may be complicated by encephalomyelitis. We investigated EV71 brainstem infection and whether this infection could be ameliorated by passive immunization in a mouse model. Enterovirus 71 was injected into unilateral jaw/facial muscles of 2-week-old mice, and hyperimmune sera were given before or after infection. Harvested tissues were studied by light microscopy, immunohistochemistry, in situ hybridization, and viral titration. In unimmunized mice, viral antigen and RNA were detected within 24 hours after infection only in ipsilateral cranial nerves, motor trigeminal nucleus, reticular formation, and facial nucleus; viral titers were significantly higher in the brainstem than in the spinal cord samples. Mice given preinfection hyperimmune serum showed a marked reduction of ipsilateral viral antigen/RNA and viral titers in the brainstem in a dose-dependent manner. With optimum hyperimmune serum given after infection, brainstem infection was significantly reduced in a time-dependent manner. A delay in disease onset and a reduction of disease severity and mortality were also observed. Thus, EV71 can directly infect the brainstem, including the medulla, via cranial nerves, most likely by retrograde axonal transport. This may explain the sudden cardiorespiratory collapse in human patients with fatal encephalomyelitis. Moreover, our results suggest that passive immunization may still benefit EV71-infected patients who have neurologic complications. PMID:25289894

Tan, Soon Hao; Ong, Kien Chai; Wong, Kum Thong

2014-11-01

114

Development of a method for detection of enteroviruses in shellfish by PCR with poliovirus as a model.  

PubMed Central

The application of the PCR to complex samples is hindered by amplification inhibitors. We describe a reverse transcription-PCR-based method capable of inhibitor removal for the detection of enteroviruses in shellfish. Initial virus extraction stages based on a modified polyethylene glycol precipitation technique (G.D. Lewis and T.G. Metcalf, Appl. Environ. Microbiol. 54:1983-1988, 1988) were followed by virus purification with 1,1,2-trichloro,2,2,1-trifluoroethane and concentration by ultrafiltration. A guanidine isothiocyanate-glass powder extraction system was utilized for sample lysis, RNase protection, and nucleic acid purification. Removal of PCR inhibitors and method sensitivity were quantified in shellfish (oysters and mussels) seeded with poliovirus. PCR sample tolerance exceeded 4 g for depurated shellfish; however, polluted field samples were more inhibitory. Virus recoveries of 31% for oyster extracts and 17% for mussel extracts and nucleic acid extraction reverse transcription-PCR detection limits down to 1 PFU yielded an overall sensitivity limit of < 10 PFU of poliovirus in up to 5 g of shellfish. PCR-positive results were obtained from a variety of polluted field samples naturally contaminated with human enteroviruses. The methods developed for virus recovery and PCR inhibitor removal should be equally applicable to detection of other RNA viruses such as hepatitis A virus, Norwalk virus, and other small round-structured viruses in shellfish. Images PMID:7521997

Lees, D N; Henshilwood, K; Doré, W J

1994-01-01

115

Kaempferol inhibits enterovirus 71 replication and internal ribosome entry site (IRES) activity through FUBP and HNRP proteins.  

PubMed

Flavonoids are associated with multiple biological and pharmacological activities, including anti-enterovirus activity. An internal ribosomal entry site (IRES) required for viral protein translation is a potential drug target for enterovirus 71 (EV71). Regulation translation initiation requires the interaction of IRES specific trans-acting host factors with viral IRES element. By evaluation of 12 flavonoids against EV71 infection, we found that (a) 7,8-dihydroxyflavone, kaempferol, quercetin, hesperetin and hesperidin exhibited more than 80% of cell survival and inhibition of EV71 infection; however, no anti-oxidative effects were noted from these flavonoids; (b) among them, only 7,8-dihydroxyflavone, kaempferol and hesperetin showed 40% of viral IRES activity; (c) kaempferol interfered with EV71 virus replication and pseudotyped virus production; and (d) FUBP1, FUBP3, HNRPD, HNRH1 and HNRPF proteins are associated with EV71 5'-UTR as shown using RNA affinity pull-down assay coupled with LC-MS/MS analysis. We firstly found that kaempferol may change the composition of these IRES associated trans-acting factors, and affect IRES function and EV71 virus replication. These studies help not only to understand the IRES function but also the mechanism by which drug induced cellular proteins are acting against EV71 infection. PMID:25212137

Tsai, Fuu-Jen; Lin, Cheng-Wen; Lai, Chien-Chen; Lan, Yu-Ching; Lai, Chih-Ho; Hung, Chien-Hui; Hsueh, Kai-Chung; Lin, Ting-Hsu; Chang, Hebron C; Wan, Lei; Sheu, Jim Jinn-Chyuan; Lin, Ying-Ju

2011-09-15

116

Combined 5' UTR RFLP analysis and VP1 sequencing for epidemic investigation of enteroviruses.  

PubMed

Enteroviruses, the main cause of aseptic meningitis, consist of 100 serotypes, and many of them have been associated with large outbreaks. In the present study, a comparison of RFLP analysis of the 5' untranslated region (5'UTR) and sequencing of both the 5'UTR and VP1 regions was conducted for epidemiological linkage of 27 clinical enterovirus strains. The clinical enterovirus strains were clustered into five restriction profile groups. Even though the restriction profile clusters of clinical isolates were not related to those of the respective prototype strains, epidemiological relationships between the members of each cluster were observed. The restriction profile clusters in the 5'UTR corresponded to the phylogenetic clusters in the VP1 genomic region. The incongruence between the topology of Gior strain in 5'UTR and VP1 phylogenetic trees indicates a recombination event. The proposed RFLP assay in combination with VP1 sequencing can offer crucial epidemiological information about the circulating enteroviruses. PMID:22983155

Kyriakopoulou, Zaharoula; Tsolis, Kostas; Pliaka, Vaia; Tsakogiannis, Dimitris; Ruether, Irina Georgia Anna; Gartzonika, Constantina; Levidiotou-Stefanou, Stamatina; Markoulatos, Panayotis

2013-01-01

117

AN INTEGRATED CELL CULTURE/RT-PCR METHOD FOR DETECTING ENTEROVIRUS IN WATER  

EPA Science Inventory

Echovirus and coxsackievirus can cause mild to severe disease following consumption of contaminated drinking water. However, comprehensive occurrence studies of enteroviruses in drinking water matrices are limited, in part because of the lack of available methods that are rapid, ...

118

.. () B.B.A. (Human Resource Management) 895-171 (3)  

E-print Network

.. () B.B.A. (Human Resource Management) 135 1. 30 1.1 12 895-171 (3) Wisdom and Applications 460-211 (3) Operations Management 460-212 (3) Business Law 460-213 (3) Human Resource Resource Procurement 460-350 (3) Labor Relations 460-351 (3) Compensation Management 460-352 (3) Human

Laksanacharoen, Sathaporn

119

Open reading frame sequence of an Asian enterovirus 73 strain reveals that the prototype from California is recombinant  

Microsoft Academic Search

Phylogenetic analysis within the VP1 region now enables molecular typing of enteroviruses consistent with neutralization results. Three untypable isolates, 2776\\/82, 57\\/99 and 22\\/00, from Korea, North India and Bangladesh, respectively, showed within this region 98-0-99-0% amino acid identities. These were less than 77% to the previous enterovirus prototypes, but 91-5-92-5% to CA55-1988, the recently identified enterovirus 73 (EV73) prototype from

Helene Norder; Lotte Bjerregaard; Lars O. Magnius

2002-01-01

120

Sensitization to bradykinin B1 and B2 receptor activation in UV-B irradiated human skin  

Microsoft Academic Search

Bradykinin B1 and B2 receptors contribute to nociceptor sensitization under inflammatory conditions. Here, we examined the vascular inflammatory responses and nociceptive effects resulting from activation of B1 and B2 receptors in healthy and UV-B irradiated skin in human volunteers. The B1 receptor agonist des-Arg10-Kallidin (10?6–10?3M) and the B2 receptor agonist bradykinin (10?9–10?4M) were administered by dermal microdialysis to the ventral

Harald Eisenbarth; Roman Rukwied; Marlen Petersen; Martin Schmelz

2004-01-01

121

Factor B of the alternative complement pathway on human lymphocytes.  

PubMed

A factor on human lymphocytes has been identified as factor B of the alternative pathway. Lymphocytes can replace factor B in the fluid phase formation of C3 convertase with cobra venom factor (CVF). This lymphocyte activity is inhibited by specific anti-human factor B, and it is shown by Burkitt lymphoma cell lines cultured in the absence of any factor B source. After the reaction with CVF all the C3-converting activity is found in the cell supernatant, and the same cells can undergo several successive cycles of 'activation' by CVF. Factor B is distinct from the C3b receptor, and its presence could not be detected antigenically on the lymphocyte membrane. It may be secreted by the cells, but the reaction was not affected by sodium azide or cytochalasin B. No detectable factor B activity was found in the culture medium of cells grown in the absence of CVF. PMID:824718

Halbwachs, L; Lachmann, P J

1976-01-01

122

Chlorogenic Acid Inhibits the Replication and Viability of Enterovirus 71 In Vitro  

PubMed Central

Enterovirus 71 (EV71) is an etiology for a number of diseases in humans. Traditional Chinese herbs have been reported to be effective for treating EV71 infection. However, there is no report about the antiviral effects of CHA against EV71. In this study, plaque reduction assay demonstrated that the inhibitory concentration 50% (IC50) of CHA on EV71 replication is 6.3 µg/ml. When both CHA (20 µg/ml) and EV71 were added, or added post-infection at different time points, CHA was able to effectively inhibit EV71 replication between 0 and 10 h. In addition, CHA inhibited EV71 2A transcription and translation in EV71-infected RD cells, but did not affect VP1, 3C, and 3D expression. Furthermore, CHA inhibited secretions of IL-6, TNF-?, IFN-? and MCP-1 in EV71-infected RD cells. Altogether, these results revealed that CHA may have antiviral properties for treating EV71 infection. PMID:24098754

Hou, Xueling; Peng, Hongjun; Zhang, Li; Shi, Mei; Ji, Yun; Wang, Yuyue

2013-01-01

123

Acute transverse myelitis associated with human parvovirus b19 infection.  

PubMed

We describe severe acute transverse myelitis in a previously healthy 9-year-old boy in whom primary human parvovirus B19 infection was confirmed serologically and B19 DNA was detected in his serum and cerebrospinal fluid. Besides erythema infectiosum, parvovirus B19 infection has various clinical manifestations; however, central nervous system involvement is rare. Even more unusual is parvovirus B19-associated acute transverse myelitis. PMID:24049056

Suzuki, Masashi; Yoto, Yuko; Ishikawa, Aki; Asakura, Hirofumi; Tsutsumi, Hiroyuki

2014-02-01

124

First isolation and genomic characterization of enterovirus A71 and coxsackievirus A16 from hand foot and mouth disease patients in the Lao PDR  

PubMed Central

Enterovirus A71 (EV-A71) and coxsackievirus A16 (CV-A16) are major aetiological agents of hand, foot and mouth disease in Asia. We established the first genomic characterization of strains isolated in 2011 from Lao patients. Isolates were related to EV-A71 genotype C4 and CV-A16 genotype B1a that circulated in neighbouring countries during the same period. This confirms the regional character of hand, foot and mouth disease epidemiology and makes plausible the occurrence of severe disease in the Lao population.

Nguyen, V H; Sibounheuang, B; Phommasone, K; Vongsouvath, M; Newton, P N; Piorkowski, G; Baronti, C; de Lamballerie, X; Dubot-Pérès, A

2014-01-01

125

Sialylated glycans as receptor and inhibitor of enterovirus 71 infection to DLD-1 intestinal cells  

PubMed Central

Background Many viruses recognize specific sugar residues, particularly sulfated or sialylated glycans, as the infection receptors. A change of sialic acid (2-6)-linked galactose (SA-?2,6Gal) to SA-?2,3Gal determines the receptor for avian flu infection. The receptor for enterovirus 71 (EV71) infection that frequently causes fatal encephalitis in Asian children remains unclear. Currently, there is no effective vaccine or anti-virus agent for EV71 infection. Using DLD-1 intestinal cells, this study investigated whether SA-linked glycan on DLD-1 intestinal cells was a receptor for EV71, and whether natural SA-linked sugars from human milk could block EV71 infection. Results EV71 specifically infected DLD-1 intestinal cells but not K562 myeloid cells. Depletion of O-linked glycans or glycolipids, but not N-linked glycans, significantly decreased EV71 infection of DLD-1 cells. Pretreatment of DLD-1 cells with sialidase (10 mU, 2 hours) significantly reduced 20-fold EV71 replication (p < 0.01). Taken together, these results suggest that SA-linked O-glycans and glycolipids, but not N-glycans, on DLD-1 cells were responsible for EV71 infection. Purified SA-?2,3Gal and SA-?2,6Gal from human milk significantly inhibited EV71 infection of DLD-1 cells, indicating terminal SA-linked glycans could be receptors and inhibitors of EV71 infection. Conclusion This is the first in the literature to demonstrate that EV71 uses SA-linked glycans as receptors for infection, and natural SA-linked glycans from human milk can protect intestinal cells from EV71 infection. Further studies will test how a SA-containing glycan can prevent EV71 in the future. PMID:19751532

Yang, Betsy; Chuang, Hau; Yang, Kuender D

2009-01-01

126

Antigenic and Receptor Binding Properties of Enterovirus 68  

PubMed Central

ABSTRACT Increased detection of enterovirus 68 (EV68) among patients with acute respiratory infections has been reported from different parts of the world in the late 2000s since its first detection in pediatric patients with lower-respiratory-tract infections in 1962. However, the underlying molecular mechanisms for this trend are still unknown. We therefore aimed to study the antigenicity and receptor binding properties of EV68 detected in recent years in comparison to the prototype strain of EV68, the Fermon strain. We first performed neutralization (NT) and hemagglutination inhibition (HI) tests using antisera generated for EV68 strains detected in recent years. We found that the Fermon strain had lower HI and NT titers than recently detected EV68 strains. The HI and NT titers were also significantly different between strains of different genetic lineages among recently detected EV68 strains. We further studied receptor binding specificities of EV68 strains for sialyloligosaccharides using glycan array analysis. In glycan array analysis, all tested EV68 strains showed affinity for ?2-6-linked sialic acids (?2-6 SAs) compared to ?2-3 SAs. Our study demonstrates that emergence of strains with different antigenicity is the possible reason for the increased detection of EV68 in recent years. Additionally, we found that EV68 preferably binds to ?2-6 SAs, which suggests that EV68 might have affinity for the upper respiratory tract. IMPORTANCE Numbers of cases of enterovirus 68 (EV68) infection in different parts of the world increased significantly in the late 2000s. We studied the antigenicity and receptor binding properties of recently detected EV68 strains in comparison to the prototype strain of EV68, Fermon. The hemagglutination inhibition (HI) and neutralization (NT) titers were significantly different between strains of different genetic lineages among recently detected EV68 strains. We further studied receptor binding specificities of EV68 strains for sialyloligosaccharides using glycan array analysis, which showed affinity for ?2-6-linked sialic acids (?2-6 SAs) compared to ?2-3 SAs. Our study suggested that the emergence of strains with different antigenicities was the possible reason for the increased detections of EV68 in recent years. Additionally, we revealed that EV68 preferably binds to ?2-6 SAs. This is the first report describing the properties of EV68 receptor binding to the specific types of sialic acids. PMID:24371050

Imamura, Tadatsugu; Okamoto, Michiko; Nakakita, Shin-ichi; Suzuki, Akira; Saito, Mariko; Tamaki, Raita; Lupisan, Socorro; Roy, Chandra Nath; Hiramatsu, Hiroaki; Sugawara, Kan-etsu; Mizuta, Katsumi; Matsuzaki, Yoko; Suzuki, Yasuo

2014-01-01

127

miRNA and tropism of human parvovirus B19.  

PubMed

Parvovirus B19 has an extreme tropism for human erythroid progenitors. Here we propose the hypothesis explaining the tropism of human parvovirus B19. Our speculations are based on experimental results related to the capsid proteins VP1 and VP2. These proteins were not detectable in nonpermissive cells in course of these experiments, although the corresponding mRNAs were synthesized. Our interpretation of these results is an inhibition of translation in nonpermissive cells by human miRNAs. We bring support to our hypothesis and propose detailed experimental procedure to test it. PMID:22902951

Berillo, Olga; Khailenko, Vladimir; Ivashchenko, Anatoly; Perlmuter-Shoshany, Lior; Bolshoy, Alexander

2012-10-01

128

Clinical and etiological characteristics of enterovirus 71-related diseases during a recent 2-year period in Korea.  

PubMed

Human enterovirus 71 (EV 71) has caused large-scale outbreaks of hand-foot-and-mouth disease (HFMD), particularly in the Asian-Pacific region. In this study, we report a major outbreak of EV 71 infection in Korea and describe the clinical differences between EV 71 and non-EV 71 enterovirus infections. We prospectively enrolled patients with suspected viral infections during a recent 2-year period through a nationwide surveillance system. We identified 719 patients with suspected HFMD or herpangina using real-time PCR and genotyping based on VP1 sequence analysis. The major pathogen causing HFMD changed substantially from 2008 to 2009, with EV 71 becoming the most common cause of HFMD in Korea in 2009. We successfully identified the enteroviral genotypes for 218 of the 719 patients. Patients with EV 71 infections tended to be younger than those with non-EV 71 enteroviral infections and presented with HFMD and meningoencephalitis. In addition, the occurrence of fever, headache, and neck stiffness was significantly higher in patients with EV 71 infections. Multivariable analysis showed that for patients presenting with HFMD, fever, or a sore throat, each covariate was independently associated with EV 71 infection; the adjusted odds ratios (with 95% confidence intervals in parentheses) for these variables were 31.86 (10.04 to 101.09), 4.76 (1.71 to 13.25), and 0.18 (0.04 to 0.77), respectively. Our results indicate that EV 71 was a major cause of HFMD in Korea during the study period. In addition, we found that clinical symptoms may be helpful in the early identification of patients with EV 71 infections. PMID:20463159

Ryu, Wi-Sun; Kang, Byounghak; Hong, Jiyoung; Hwang, Seoyeon; Kim, Jonghyun; Cheon, Doo-Sung

2010-07-01

129

Clinical and Etiological Characteristics of Enterovirus 71-Related Diseases during a Recent 2-Year Period in Korea?  

PubMed Central

Human enterovirus 71 (EV 71) has caused large-scale outbreaks of hand-foot-and-mouth disease (HFMD), particularly in the Asian-Pacific region. In this study, we report a major outbreak of EV 71 infection in Korea and describe the clinical differences between EV 71 and non-EV 71 enterovirus infections. We prospectively enrolled patients with suspected viral infections during a recent 2-year period through a nationwide surveillance system. We identified 719 patients with suspected HFMD or herpangina using real-time PCR and genotyping based on VP1 sequence analysis. The major pathogen causing HFMD changed substantially from 2008 to 2009, with EV 71 becoming the most common cause of HFMD in Korea in 2009. We successfully identified the enteroviral genotypes for 218 of the 719 patients. Patients with EV 71 infections tended to be younger than those with non-EV 71 enteroviral infections and presented with HFMD and meningoencephalitis. In addition, the occurrence of fever, headache, and neck stiffness was significantly higher in patients with EV 71 infections. Multivariable analysis showed that for patients presenting with HFMD, fever, or a sore throat, each covariate was independently associated with EV 71 infection; the adjusted odds ratios (with 95% confidence intervals in parentheses) for these variables were 31.86 (10.04 to 101.09), 4.76 (1.71 to 13.25), and 0.18 (0.04 to 0.77), respectively. Our results indicate that EV 71 was a major cause of HFMD in Korea during the study period. In addition, we found that clinical symptoms may be helpful in the early identification of patients with EV 71 infections. PMID:20463159

Ryu, Wi-Sun; Kang, Byounghak; Hong, Jiyoung; Hwang, Seoyeon; Kim, Jonghyun; Cheon, Doo-Sung

2010-01-01

130

Considerations for developing an immunization strategy with enterovirus 71 vaccine.  

PubMed

Enterovirus 71 (EV71) is a common pathogen for hand, foot, and mouth disease (HFMD), which has significant morbidity and mortality, and for which children aged 6-59 months age are at highest risk. Due to lack of effective treatment options, control of EV71 epidemics has mainly focused on development of EV71 vaccines. Clinical trials have been completed on 3 EV71 vaccines, with trial results demonstrating good vaccine efficacy and safety. When EV71 vaccine is approved by China's national regulatory authority, an evidence-based strategy should be developed to optimize impact and safety. An immunization strategy for EV71 vaccine should consider several factors, including the target population age group, the number of doses for primary immunization, the need for a booster dose, concomitant administration of other vaccines, economic value, program capacity and logistics, and public acceptance. Once EV71 vaccines are in use, vaccine effectiveness and safety must be monitored in large populations, and the epidemiology of HFMD must be evaluated to assure a match between vaccination strategy and epidemiology. Evaluation in China is especially important because there are no other EV71 vaccines globally. PMID:25444807

Li, Li; Yin, Hongzhang; An, Zhijie; Feng, Zijian

2014-11-01

131

Cell Surface Vimentin Is an Attachment Receptor for Enterovirus 71  

PubMed Central

ABSTRACT Enterovirus 71 (EV71) is a highly transmissible pathogenic agent that causes severe central nervous system diseases in infected infants and young children. Here, we reported that EV71 VP1 protein could bind to vimentin intermediate filaments expressed on the host cell surface. Soluble vimentin or an antibody against vimentin could inhibit the binding of EV71 to host cells. Accompanied with the reduction of vimentin expression on the cell surface, the binding of EV71 to cells was remarkably decreased. Further evidence showed that the N terminus of vimentin is responsible for the interaction between EV71 and vimentin. These results indicated that vimentin on the host cell surface may serve as an attachment site that mediated the initial binding and subsequently increased the infectivity of EV71. IMPORTANCE This study delivers important findings on the roles of vimentin filaments in relation to EV71 infection and provides information that not only improves our understanding of EV71 pathogenesis but also presents us with potentially new strategies for the treatment of diseases caused by EV71 infections. PMID:24623428

Du, Ning; Cong, Haolong; Tian, Hongchao; Zhang, Hua; Zhang, Wenliang; Song, Lei

2014-01-01

132

Rapid determination of vitamin B2 and B12 in human urine by isocratic liquid chromatography.  

PubMed

A simple and rapid method for the identification and quantification of vitamin B(2) and B(12) in human urine has been developed using reverse phase high performance liquid chromatography (HPLC) and the peaks identity were confirmed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). HPLC separation was performed in single wavelength detector (lambda(365)) mode and separated isocratically using mobile phase methanol: 1mM aqueous TFA (1:4) in C18 column. The calibration graphs plotted with different concentrations of vitamin B(2) and B(12) was linear with a correlation coefficients (r(2))=0.9975 and 0.9985, respectively. The recoveries of vitamin B(2) and B(12) were above 87% and 90%, respectively. The results of this present study suggest that the proposed method may be simple and convenient way of identifying and quantifying vitamin B(2) and B(12) from human urine. PMID:19362629

Mandal, Santi M; Mandal, Mahitosh; Ghosh, Ananta K; Dey, Satyahari

2009-04-27

133

Human combinatorial antibody libraries to hepatitis B surface antigen.  

PubMed Central

Human antibody Fab fragments that bind to hepatitis B surface antigen (HBsAg) were generated by using a recombinant phage surface-display expression system. Characterization of HBsAg-specific Fab fragments isolated from two vaccinated individuals reveals diversity in specificity of antigen binding and in the sequences of the complementarity-determining region. The sequence results show examples of human light-chain promiscuity that result in fine specificity changes and a strong relationship to a human germ-line gene. This application illustrates further that this technique is a powerful tool to isolate distinct human antibodies against immunogenic viral targets. Images PMID:1373487

Zebedee, S L; Barbas, C F; Hom, Y L; Caothien, R H; Graff, R; DeGraw, J; Pyati, J; LaPolla, R; Burton, D R; Lerner, R A

1992-01-01

134

Expression of T cell receptor genes in human B cells  

PubMed Central

We analyzed the transcription and rearrangement of the T cell antigen receptor (Ti) genes Ti alpha and Ti beta in human B cell, T cell, and myeloid cell lines, as well as in purified tonsillar B and T cells. All four B cell lines examined, as well as one of two myeloid cell lines, expressed low levels of truncated Ti beta transcripts, as did freshly purified tonsillar B cells. Two of the B cell lines and one of the myeloid lines also expressed truncated Ti alpha transcripts, while tonsillar B cells did not. Sequence analysis of cDNA clones from a B cell line demonstrated that these truncated Ti alpha and Ti beta transcripts were composed of unrearranged J and C gene segments. Comparison of cDNA clones from T and B cells suggests that D alpha genes or N regions contribute to the formation of Ti alpha transcripts in T cells but not in B cells. None of the B cell or myeloid cell lines in this study showed evidence of Ti beta gene rearrangements by Southern blotting. Our data, and other studies of gene rearrangements in human tumors, demonstrate that the level of Ti beta transcriptional activity and the frequency of Ti beta gene rearrangements are correlated in all cell types examined. Thus, our data support the accessibility model of antigen receptor gene rearrangement, whereby the susceptibility of gene segments to recombination enzymes is correlated with their transcriptional activity. PMID:2431093

1986-01-01

135

Age effects on B cells and humoral immunity in humans  

PubMed Central

Both humoral and cellular immune responses are impaired in aged individuals, leading to decreased vaccine responses. Although T cell defects occur, defects in B cells play a significant role in age-related humoral immune changes. The ability to undergo class switch recombination (CSR), the enzyme for CSR, AID (activation-induced cytidine deaminase) and the transcription factor E47 are all decreased in aged stimulated B cells. We here present an overview of age-related changes in human B cell markers and functions, and also discuss some controversies in the field of B cell aging. PMID:20728581

Frasca, Daniela; Diaz, Alain; Romero, Maria; Landin, Ana Marie; Blomberg, Bonnie B

2010-01-01

136

Antiviral effects of two Ganoderma lucidum triterpenoids against enterovirus 71 infection.  

PubMed

Enterovirus 71 (EV71) is a major causative agent for hand, foot and mouth disease (HFMD), and fatal neurological and systemic complications in children. However, there is currently no clinical approved antiviral drug available for the prevention and treatment of the viral infection. Here, we evaluated the antiviral activities of two Ganoderma lucidum triterpenoids (GLTs), Lanosta-7,9(11),24-trien-3-one,15;26-dihydroxy (GLTA) and Ganoderic acid Y (GLTB), against EV71 infection. The results showed that the two natural compounds display significant anti-EV71 activities without cytotoxicity in human rhabdomyosarcoma (RD) cells as evaluated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell proliferation assay. The mechanisms by which the two compounds affect EV71 infection were further elucidated by three action modes using Ribavirin, a common antiviral drug, as a positive control. The results suggested that GLTA and GLTB prevent EV71 infection through interacting with the viral particle to block the adsorption of virus to the cells. In addition, the interactions between EV71 virion and the compounds were predicated by computer molecular docking, which illustrated that GLTA and GLTB may bind to the viral capsid protein at a hydrophobic pocket (F site), and thus may block uncoating of EV71. Moreover, we demonstrated that GLTA and GLTB significantly inhibit the replication of the viral RNA (vRNA) of EV71 replication through blocking EV71 uncoating. Thus, GLTA and GLTB may represent two potential therapeutic agents to control and treat EV71 infection. PMID:24845570

Zhang, Wenjing; Tao, Junyan; Yang, Xiaoping; Yang, Zhuliang; Zhang, Li; Liu, Hongsheng; Wu, Kailang; Wu, Jianguo

2014-07-01

137

A Mouse-Adapted Enterovirus 71 Strain Causes Neurological Disease in Mice after Oral Infection  

PubMed Central

A mouse-adapted enterovirus 71 (EV71) strain with increased virulence in mice, MP4, was generated after four serial passages of the parental EV71 strain 4643 in mice. Strain MP4 exhibited a larger plaque size, grew more rapidly, and was more cytotoxic in vitro than strain 4643. Although strains 4643 and MP4 both induced apoptosis of SK-N-SH human neuroblastoma cells, MP4 was more virulent than 4643 in 1-day-old mice (50% lethal doses, 102 and 104 PFU/mouse, respectively). Strain MP4 (5 × 106 PFU/mouse), but not 4643, could orally infect 7-day-old mice, resulting in rear-limb paralysis followed by death 5 to 9 days after inoculation with the virus. Histopathologically, neuronal loss and apoptosis were evident in the spinal cords as well as the brain stems of the infected mice. The limb muscles displayed massive necrosis. There was early and transient virus replication in the intestines, whereas the spinal cord, brain, and muscle became the sites of viral replication during the late phase of the infection. Virus transmission occurred among infected and noninfected cagemates, as demonstrated by the occurrence of seroconversion and the presence of viable viruses in the stool samples of the latter. Protection against EV71 challenge was demonstrated following administration of hyperimmune serum 1 day after inoculation with the virus. Nucleotide sequence analysis of the genome of EV71 strain MP4 revealed four nucleotide changes on the 5? untranslated region, three on the VP2 region, and eight on the 2C region, resulting in one and four amino acid substitutions in the VP2 and 2C proteins, respectively. PMID:15254164

Wang, Ya-Fang; Chou, Chun-Ting; Lei, Huan-Yao; Liu, Ching-Chuan; Wang, Shih-Min; Yan, Jing-Jou; Su, Ih-Jen; Wang, Jen-Reng; Yeh, Trai-Ming; Chen, Shun-Hua; Yu, Chun-Keung

2004-01-01

138

Exploiting Human Memory B Cell Heterogeneity for Improved Vaccine Efficacy  

PubMed Central

The major goal in vaccination is establishment of long-term, prophylactic humoral memory to a pathogen. Two major components to long-lived humoral memory are plasma cells for the production of specific immunoglobulin and memory B cells that survey for their specific antigen in the periphery for later affinity maturation, proliferation, and differentiation. The study of human B cell memory has been aided by the discovery of a general marker for B cell memory, expression of CD27; however, new data suggests the existence of CD27? memory B cells as well. These recently described non-canonical memory populations have increasingly pointed to the heterogeneity of the memory compartment. The novel B memory subsets in humans appear to have unique origins, localization, and functions compared to what was considered to be a “classical” memory B cell. In this article, we review the known B cell memory subsets, the establishment of B cell memory in vaccination and infection, and how understanding these newly described subsets can inform vaccine design and disease treatment. PMID:22566866

Pauli, Noel T.; Henry Dunand, Carole J.; Wilson, Patrick C.

2011-01-01

139

Acute human parvovirus b19 infection: cytologic diagnosis.  

PubMed

Human parvovirus B19 is highly tropic to human bone marrow and replicates only in erythroid progenitor cells. It is causative agent of transient aplastic crisis in patients with chronic haemolytic anemia. In immunocompromised patients persistent parvovirus B19 infection may develop and it manifests as pure red cell aplasia and chronic anaemia. Bone marrow is characterised morphologically by giant pronormoblast stage with little or no further maturation. We encountered a case of 6 year old HIV positive male child presented with pure red cell aplasia due to parvovirus B19 infection. Bone marrow aspiration cytology revealed giant pronormoblast with prominent intranuclear inclusions led to suspicion of parvovirus B19 infection which was confirmed by DNA PCR. This case is presented to report classical morphological features of parvovirus B19 infection rarely seen on bone marrow examination should warrant the suspicion of human parvovirus B19 infection in the setting of HIV positive patient with repeated transfusions and confirmation should be done by PCR. PMID:25332559

Sharada Raju, Rane; Nalini Vinayak, Kadgi; Madhusudan Bapat, Vishnuprasad; Preeti Balkisanji, Agrawal; Shaila Chandrakant, Puranik

2014-09-01

140

EFFECT OF PARTICULATES ON DISINFECTION OF ENTEROVIRUSES IN WATER BY CHLORINE DIOXIDE  

EPA Science Inventory

The inactivation kinetics of ClO2 on two enteroviruses, poliovirus 1 (Mahoney) and coxsackie virus A9, and an enteric indicator of fecal pollution, Escherichia coli, were examined in laboratory studies. In addition, the disinfecting ability of ClO2 as affected by particulates (bo...

141

RAPID PCR-BASED MONITORING OF INFECTIOUS ENTEROVIRUSES IN DRINKING WATER. (R824756)  

EPA Science Inventory

Abstract Currently, the standard method for the detection of enteroviruses and hepatitis A virus in water involves cell culture assay which is expensive and time consuming. Direct RT-PCR offers a rapid and sensitive alternative to virus detection but sensitivity is oft...

142

Expression of Cholesterol Sulfotransferase (SULT2B1b) in Human Skin and Primary Cultures of Human Epidermal Keratinocytes  

Microsoft Academic Search

Cholesterol sulfate is a highly amphipathic molecule that is present in a relatively high concentration in the epidermis of human skin, particularly in the granular layer. The physiologic significance of this finding, however, is not well-understood. Therefore, we examined expression of the gene encoding for the enzyme that sulfonates cholesterol (SULT2B1b). Of the three enzymes known to sulfonate steroids\\/sterols, only

Yuko Higashi; Hirotoshi Fuda; Hidekatsu Yanai; Young Lee; Tomoko Fukushige; Tamotsu Kanzaki; Charles A. Strott

2004-01-01

143

Human Rhinoviruses  

PubMed Central

Human rhinoviruses (HRVs), first discovered in the 1950s, are responsible for more than one-half of cold-like illnesses and cost billions of dollars annually in medical visits and missed days of work. Advances in molecular methods have enhanced our understanding of the genomic structure of HRV and have led to the characterization of three genetically distinct HRV groups, designated groups A, B, and C, within the genus Enterovirus and the family Picornaviridae. HRVs are traditionally associated with upper respiratory tract infection, otitis media, and sinusitis. In recent years, the increasing implementation of PCR assays for respiratory virus detection in clinical laboratories has facilitated the recognition of HRV as a lower respiratory tract pathogen, particularly in patients with asthma, infants, elderly patients, and immunocompromised hosts. Cultured isolates of HRV remain important for studies of viral characteristics and disease pathogenesis. Indeed, whether the clinical manifestations of HRV are related directly to viral pathogenicity or secondary to the host immune response is the subject of ongoing research. There are currently no approved antiviral therapies for HRVs, and treatment remains primarily supportive. This review provides a comprehensive, up-to-date assessment of the basic virology, pathogenesis, clinical epidemiology, and laboratory features of and treatment and prevention strategies for HRVs. PMID:23297263

Lamson, Daryl M.; St. George, Kirsten; Walsh, Thomas J.

2013-01-01

144

Human kidney anion exchanger 1 interacts with kinesin family member 3B (KIF3B)  

SciTech Connect

Highlights: {yields} Impaired trafficking of kAE1 causes distal renal tubular acidosis (dRTA). {yields} The interaction between kAE1 and kinesin family member 3B (KIF3B) is reported. {yields} The co-localization between kAE and KIF3B was detected in human kidney tissues. {yields} A marked reduction of kAE1 on the cell membrane was observed when KIF3B was knockdown. {yields} KFI3B plays an important role in trafficking of kAE1 to the plasma membrane. -- Abstract: Impaired trafficking of human kidney anion exchanger 1 (kAE1) to the basolateral membrane of {alpha}-intercalated cells of the kidney collecting duct leads to the defect of the Cl{sup -}/HCO{sub 3}{sup -} exchange and the failure of proton (H{sup +}) secretion at the apical membrane of these cells, causing distal renal tubular acidosis (dRTA). In the sorting process, kAE1 interacts with AP-1 mu1A, a subunit of AP-1A adaptor complex. However, it is not known whether kAE1 interacts with motor proteins in its trafficking process to the plasma membrane or not. We report here that kAE1 interacts with kinesin family member 3B (KIF3B) in kidney cells and a dileucine motif at the carboxyl terminus of kAE1 contributes to this interaction. We have also demonstrated that kAE1 co-localizes with KIF3B in human kidney tissues and the suppression of endogenous KIF3B in HEK293T cells by small interfering RNA (siRNA) decreases membrane localization of kAE1 but increases its intracellular accumulation. All results suggest that KIF3B is involved in the trafficking of kAE1 to the plasma membrane of human kidney {alpha}-intercalated cells.

Duangtum, Natapol [Medical Molecular Biology Unit, Office for Research and Development Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand) [Medical Molecular Biology Unit, Office for Research and Development Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand); Department of Anatomy, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand); Junking, Mutita; Sawasdee, Nunghathai [Medical Molecular Biology Unit, Office for Research and Development Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand)] [Medical Molecular Biology Unit, Office for Research and Development Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand); Cheunsuchon, Boonyarit [Department of Pathology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand)] [Department of Pathology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand); Limjindaporn, Thawornchai, E-mail: limjindaporn@yahoo.com [Department of Anatomy, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand)] [Department of Anatomy, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand); Yenchitsomanus, Pa-thai, E-mail: grpye@mahidol.ac.th [Medical Molecular Biology Unit, Office for Research and Development Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand)] [Medical Molecular Biology Unit, Office for Research and Development Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand)

2011-09-16

145

Method 1615: Measurement of Enterovirus and Norovirus Occurrence in Water by Culture and RT-qPCR  

EPA Science Inventory

Version 1.1 - Enteroviruses and noroviruses that may be present in environmental or finished drinking waters are concentrated by passage through electropositive filters. Viruses are eluted from the filters with a beef extract reagent and concentrated using organic flocculation....

146

Identification of the human mature B cell miRNome  

PubMed Central

The full set of microRNAs (miRNAs) in the human genome is not known. Because presently known miRNAs have been identified by virtue of their abundant expression in a few cell types, many tissue-specific miRNAs remain unrevealed. To understand the role of miRNAs in B-cell function and lymphomagenesis, we generated short-RNA libraries from normal human B cells at different stages of development (naïve, germinal-center, memory) and from a Burkitt lymphoma cell-line. A combination of cloning and computational analysis identified 178 miRNAs (miRNome) expressed in normal and/or transformed B-cell libraries. Most notably, the B-cell miRNome included 75 miRNAs which to our knowledge have not been previously reported and of which 66 have been validated by RNA blot and/or RT-PCR analyses. Numerous miRNAs were expressed in a stage- or transformation-specific fashion in B cells, suggesting specific functional or pathologic roles. These results provide a resource for studying the role of miRNAs in B-cell development, immune function, and lymphomagenesis. PMID:19446474

Basso, Katia; Sumazin, Pavel; Morozov, Pavel; Schneider, Christof; Maute, Roy L.; Kitagawa, Yukiko; Mandelbaum, Jonathan; Haddad, Joseph; Chen, Chang-Zheng; Califano, Andrea; Dalla-Favera, Riccardo

2009-01-01

147

Novel transcription map for the B19 (human) pathogenic parvovirus.  

PubMed Central

The B19 parvovirus, a small single-stranded DNA virus of 5.4 kilobases, is pathogenic in humans. B19 has remarkable specificity for erythroid progenitor cells and has been propagated in vitro only with human erythroid bone marrow. Replication of viral DNA and the viral protein products of B19 appear similar to those of other animal parvoviruses. However, B19 transcription had unusual features in comparison with that in other animal parvoviruses. At least nine overlapping poly(A)+ transcripts were identified in infected cells; all but one contained large introns. B19 differed from other parvoviruses in the initiation of all transcripts at a strong left side promoter (p6) and the absence of a functional internal promoter; the presence of short 5' leader sequences of about 60 bases and very large introns for RNAs encoded by the right side of the genome; two separate transcription termination sites, in contrast to cotermination at the far right side of the genome for other parvoviruses; the probable utilization by three transcripts of a variant polyadenylation signal (ATTAAA or AATAAC) in the middle of the genome; and the abundance of two unique transcripts from the middle of the genome which did not code for capsid proteins. The unusual transcription map of B19 suggests that regulation of the relative abundance of transcripts occurs by splicing and termination-polyadenylation events rather than by promoter strength. In combination with the published nucleotide sequence, the novel transcription map separated the pathogenic B19 virus at a molecular level from other animal parvoviruses and human adeno-associated virus. Images PMID:3599180

Ozawa, K; Ayub, J; Hao, Y S; Kurtzman, G; Shimada, T; Young, N

1987-01-01

148

Fumonisin B? modulates expression of human cytochrome P450 1b1 in human hepatoma (Hepg2) cells by repressing Mir-27b.  

PubMed

Fumonisin B? (FB?), a common mycotoxin contaminant of maize, is known to inhibit sphingolipid biosynthesis and has been implicated in hepatocellular carcinoma promoting activity in humans and animals. MicroRNAs (miRNA) are small noncoding RNAs that regulate gene expression via translational repression. Human cytochrome P450 (CYP1B1) is highly expressed in oestrogen target tissues and catalyzes the metabolic activation of many procarcinogens. The aim of our study was to investigate the effect of FB? on miR-27b suppression and its effect on CYP1B1 modulation in a human hepatoma cell line (HepG2). MiR27b and CYP1B1 expressions were evaluated in HepG2 cells by quantitative PCR. In order to directly assess the effect of miR-27b on CYP1B1 mRNA levels, cells were transfected with the mimic to miR-27b. CYP1B1 protein expression was measured using Western blot. FB? significantly down-regulated (11-fold) expression of miR-27b in HepG2 cells; whilst CYP1B1 mRNA and protein expression was significantly upregulated by 1.8-fold and 2.6-fold, respectively. CYP1B1 is post-transcriptionally regulated by miR-27b after HepG2 exposure to FB?. FB?-induced modulation of miR-27b in hepatic cells may be an additional mode of hepatic neoplastic transformation. PMID:24614526

Chuturgoon, Anil A; Phulukdaree, Alisa; Moodley, Devapregasan

2014-05-16

149

Combining Multiplex Reverse Transcription-PCR and a Diagnostic Microarray To Detect and Differentiate Enterovirus 71 and Coxsackievirus A16  

PubMed Central

Cluster A enteroviruses, including enterovirus 71 (EV71) and coxsackievirus A16 (CA16), are known to cause hand-foot-and-mouth disease (HFMD). Despite the close genetic relationship between these two viruses, EV71 is generally known to be a more perpetuating pathogen involved in severe clinical manifestations and deaths. While the serotyping of enteroviruses is mostly done by conventional immunological methods, many clinical isolates remain unclassifiable due to the limited number of antibodies against enterovirus surface proteins. Array-based assays are able to detect several serotypes with high accuracy. We combined an enterovirus microarray with multiplex reverse transcription-PCR to try to develop a method of sensitively and accurately detecting and differentiating EV71 and CA16. In an effort to design serotype-specific probes for detection of the virus, we first did an elaborate bioinformatic analysis of the sequence database derived from different enterovirus serotypes. We then constructed a microarray using 60-mer degenerate oligonucleotide probes covalently bound to array slides. Using this enterovirus microarray to study 144 clinical specimens from patients infected with HFMD or suspected to have HFMD, we found that it had a diagnostic accuracy of 92.0% for EV71 and 95.8% for CA16. Diagnostic accuracy for other enteroviruses (non-EV71 or -CA16) was 92.0%. All specimens were analyzed in parallel by real-time PCR and subsequently confirmed by neutralization tests. This highly sensitive array-based assay may become a useful alternative in clinical diagnostics of EV71 and CA16. PMID:16757623

Chen, Tsan-Chi; Chen, Guang-Wu; Hsiung, Chao Agnes; Yang, Jyh-Yuan; Shih, Shin-Ru; Lai, Yiu-Kay; Juang, Jyh-Lyh

2006-01-01

150

Rapid and Sensitive Routine Detection of All Members of the Genus Enterovirus in Different Clinical Specimens by Real-Time PCR  

Microsoft Academic Search

We developed a rapid and sensitive method for the routine detection of all members of the enterovirus genus in different clinical specimens by using real-time TaqMan quantitative PCR. Multiple primer and probe sets were selected in the highly conserved 5-untranslated region of the enterovirus genome. Our assay detected all 60 different enterovirus species tested, whereas no reactivity was observed with

Monique Nijhuis; Noortje van Maarseveen; Rob Schuurman; Sandra Verkuijlen; Machiel de Vos; Karin Hendriksen; Anton M. van Loon

2002-01-01

151

Production of lymphotoxin by isolated human tonsillar B lymphocytes and B lymphocyte cell lines.  

PubMed Central

The expression of lymphotoxin (LT) mRNA and cytokine in human tonsillar B cells and B cell lines was examined by Northern blots and cytotoxicity assays, respectively. In tonsillar B cells, phorbol myristate acetate (PMA) or Staphylococcus aureus Cowan l (SAC) alone induced low levels of LT mRNA accumulation. However, SAC and anti-mu were strongly synergistic with PMA in this induction. Peak LT mRNA expression in tonsillar B cells stimulated by PMA plus SAC occurred between 48 and 72 h and was approximately half as much as that in PMA plus anti-CD3-stimulated T cells. Cyclosporine A was not effective in inhibiting LT mRNA accumulation by stimulated tonsillar B cells. A number of B cell lines could also be stimulated by PMA to express LT mRNA. Peak accumulation of LT mRNA in the cell line RPMI 1788 stimulated with PMA peaked about 8 h. A23187 in combination with PMA caused this accumulation to increase slightly and to peak earlier. The cytotoxic effects in the supernatants of stimulated B cells were contributed mostly by LT. The results indicate that tonsillar B cells are important in LT production and that there are important differences in the stimulation requirements for LT production and in LT mRNA expression kinetics between tonsillar B cells and B cell lines. Images PMID:2786889

Sung, S S; Jung, L K; Walters, J A; Jeffes, E W; Granger, G A; Fu, S M

1989-01-01

152

Immunobiology Human blood IgM "memory" B cells are circulating splenic marginal zone B cells harboring  

E-print Network

1 Immunobiology Human blood IgM "memory" B cells are circulating splenic marginal zone B cells expression profiling of the different blood and splenic B cell subsets, that blood IgM+ IgD+ CD27+ cells cells in human Sandra Weller1 , Moritz C. Braun1 , Bruce K. Tan2 , Andreas Rosenwald2 , Corinne Cordier3

Paris-Sud XI, Université de

153

Enterovirus genome detection in wastewater: multi centric evaluation of a commercial kit.  

PubMed

A multi-centric study was carried out in three laboratories, to evaluate the efficiency of a standardized kit for the detection of enterovirus genome in wastewater. Twenty one samples of 20 liters of wastewater were analyzed before and after concentration through glass wool. Each sample was analyzed with the Amplicor kit as well as with techniques developed independently in each laboratory. The results show that the Amplicor kit is well suited to the detection of enterovirus genome in treated wastewater. The results may be compared to those obtained with semi-nested RT-PCR techniques used in each laboratory. However, the Amplicor kit technique is more simple and has the advantage of providing a standardized technique useful for comparative studies. During this work it was observed that the sensitivity of the detection of infectious viruses and virus genome was improved when concentrated samples were used for analysis. PMID:10418098

Gantzer, C; Menard, D; Lina, B; Maul, A; Le Guyader, S; Thouvenot, D; Aymard, M; Schwartzbrod, L; Kopecka, H

1999-06-01

154

Prevalence, genetic diversity and recombination of species G enteroviruses infecting pigs in Vietnam.  

PubMed

Picornaviruses infecting pigs, described for many years as 'porcine enteroviruses', have recently been recognized as distinct viruses within three distinct genera (Teschovirus, Sapelovirus and Enterovirus). To better characterize the epidemiology and genetic diversity of members of the Enterovirus genus, faecal samples from pigs from four provinces in Vietnam were screened by PCR using conserved enterovirus (EV)-specific primers from the 5' untranslated region (5' UTR). High rates of infection were recorded in pigs on all farms, with detection frequencies of approximately 90% in recently weaned pigs but declining to 40% in those aged over 1 year. No differences in EV detection rates were observed between pigs with and without diarrhoea [74% (n = 70) compared with 72% (n = 128)]. Genetic analysis of consensus VP4/VP2 and VP1 sequences amplified from a subset of EV-infected pigs identified species G EVs in all samples. Among these, VP1 sequence comparisons identified six type 1 and seven type 6 variants, while four further VP1 sequences failed to group with any previously identified EV-G types. These have now been formally assigned as EV-G types 8-11 by the Picornavirus Study Group. Comparison of VP1, VP4/VP2, 3D(pol) and 5' UTRs of study samples and those available on public databases showed frequent, bootstrap-supported differences in their phylogenies indicative of extensive within-species recombination between genome regions. In summary, we identified extremely high frequencies of infection with EV-G in pigs in Vietnam, substantial genetic diversity and recombination within the species, and evidence for a much larger number of circulating EV-G types than currently described. PMID:24323635

Van Dung, Nguyen; Anh, Pham Hong; Van Cuong, Nguyen; Hoa, Ngo Thi; Carrique-Mas, Juan; Hien, Vo Be; Campbell, James; Baker, Stephen; Farrar, Jeremy; Woolhouse, Mark E; Bryant, Juliet E; Simmonds, Peter

2014-03-01

155

Expression, purifi cation and characterization of enterovirus-71 virus-like particles  

Microsoft Academic Search

AIM: Enterovirus 71 (EV71) has been implicated as the etiological agent responsible for the recent outbreaks of hand, foot and mouth disease associated with severe neurological diseases in the Asia-Pacifi c region. METHODS: The assembly process was hypothesized to occur via an orchestrated proteolytic processing of the P1 precursor by the viral protease 3CD. To test this hypothesis, we constructed

Chung YC; Huang JH; Lai CW; Sheng HC; Yao-Chi Chung; Jen-Huang Huang; Chia-Wei Lai; Heng-Chun Sheng; Shin-Ru Shih; Mei-Shang Ho; Yu-Chen Hu

156

Differential interferon pathway gene expression patterns in Rhabdomyosarcoma cells during Enterovirus 71 or Coxsackievirus A16 infection.  

PubMed

Exposure of cells to type I interferon (IFN) induces an antiviral state that prevents viral infection, but viruses can utilize multiple tactics to antagonize the host immune system. Enterovirus 71 (EV71) and Coxsackievirus A16 (CVA16) are two major pathogens that cause hand, foot, and mouth disease (HFMD), which is prevalent among children. We found that both EV71 and CA16 have different reactions to type I IFN pretreatment and induction patterns of type I IFN on Rhabdomyosarcoma (RD) cells. Further, a human-? and ? IFN PCR array was employed to analyze the expressions of 84 genes related to the type I IFN pathway. We found significant up-regulation of multiple genes in the presence of type I IFN and differential regulation patterns during EV71 or CA16 infection in RD cells. For instance, EV71 infection repressed the JAK-STAT signaling pathway and interferon-stimulated gene (ISG) expression, whereas CA16 infection normally triggers the JAK-STAT pathway, leading to the expression of ISGs. Taken together, this study provides a comprehensive view of the differential impacts of EV71 and CA16 infection on 84 genes in the IFN pathway, shedding light on the different resistances of these viruses to type I IFN treatment and cytotoxic effects in RD cells. PMID:24735544

Zhang, Wei; Zhang, Lei; Wu, Zhiyong; Tien, Po

2014-05-01

157

High sensitivity and label-free detection of Enterovirus 71 by nanogold modified electrochemical impedance spectroscopy  

NASA Astrophysics Data System (ADS)

Enterovirus 71 (EV71), which is the most fulminant and invasive species of enterovirus, can cause children neurologic complications and death within 2-3 days after fever and rash developed. Besides, EV71 has high sequence similarity with Coxsackie A 16 (CA16) that makes differential diagnosis difficult in clinic and laboratory. Since conventional viral diagnostic method cannot diagnose EV71 quickly and EV71 can transmit at low viral titer, the patients might delay in treatment. A quick, high sensitive, and high specific test for EV71 detection is pivotal. Electrochemical impedance spectroscopy (EIS) has been applied for detecting bio-molecules as biosensors recently. In this study, we try to build a detection platform for EV71 detection by nanogold modified EIS probe. The result shows that our probe can detect 3.6 VP1/50 ?l (one EV71 particle has 60 VP1) in 3 minutes. The test can also distinguish EV71 from CA16 and lysozyme. Diagnosis of enterovirus 71 by electrochemical impedance spectroscopy has the potential to apply in clinic.

Wang, Fang-Yu; Li, Hsing-Yuan; Tseng, Shing-Hua; Cheng, Tsai-Mu; Chu, Hsueh-Liang; Yang, Jyh-Yuan; Chang, Chia-Ching

2013-03-01

158

Identification of specific antigenic epitope at N-terminal segment of enterovirus 71 (EV-71) VP1 protein and characterization of its use in recombinant form for early diagnosis of EV-71 infection.  

PubMed

Human enterovirus 71 (EV-71) is the main etiologic agent of hand, foot and mouth disease (HFMD). We sought to identify EV-71 specific antigens and develop serologic assays for acute-phase EV-71 infection. A series of truncated proteins within the N-terminal 100 amino acids (aa) of EV-71 VP1 was expressed in Escherichia coli. Western blot (WB) analysis showed that positions around 11-21 aa contain EV-71-specific antigenic sites, whereas positions 1-5 and 51-100 contain epitopes shared with human coxsackievirus A16 (CV-A16) and human echovirus 6 (E-6). The N-terminal truncated protein of VP1, VP?????, exhibited good stability and was recognized by anti-EV-71 specific rabbit sera. Alignment analysis showed that VP????? is highly conserved among EV-71 strains from different genotypes but was heterologous among other enteroviruses. When the GST-VP????? fusion protein was incorporated as antibody-capture agent in a WB assay and an ELISA for detecting anti-EV-71 IgM in human sera, sensitivities of 91.7% and 77.8% were achieved, respectively, with 100% specificity for both. The characterized EV-71 VP1 protein truncated to positions 6-43 aa has potential as an antigen for detection of anti-EV-71 IgM for early diagnosis of EV-71 infection in a WB format. PMID:24952304

Zhang, Jianhua; Jiang, Bingfu; Xu, Mingjie; Dai, Xing; Purdy, Michael A; Meng, Jihong

2014-08-30

159

Hepatitis B and human immunodeficiency virus co-infection  

PubMed Central

Hepatitis B and human immunodeficiency virus (HBV and HIV) infection share transmission patterns and risk factors, which explains high prevalence of chronic HBV infection in HIV infected patients. The natural course of HBV disease is altered by the HIV infection with less chance to clear acute HBV infection, faster progression to cirrhosis and higher risk of liver-related death in HIV-HBV co-infected patients than in HBV mono-infected ones. HIV infected patients with chronic hepatitis B should be counseled for liver damage and surveillance of chronic hepatitis B should be performed to screen early hepatocellular carcinoma. Noninvasive tools are now available to evaluate liver fibrosis. Isolated hepatitis B core antibodies (anti-HBc) are a good predictive marker of occult HBV infection. Still the prevalence and significance of occult HBV infection is controversial, but its screening may be important in the management of antiretroviral therapy. Vaccination against HBV infection is recommended in non-immune HIV patients. The optimal treatment for almost all HIV-HBV co-infected patients should contain tenofovir plus lamivudine or emtricitabine and treatment should not be stopped to avoid HBV reactivation. Long term tenofovir therapy may lead to significant decline in hepatitis B surface Antigen. The emergence of resistant HBV strains may compromise the HBV therapy and vaccine therapy. PMID:25516647

Phung, Bao-Chau; Sogni, Philippe; Launay, Odile

2014-01-01

160

[Non detection of enterovirus in the bivalve Anadara tuberculosa (Bivalvia:Arcidae) caused by chemical contamination in the Pacific of Costa Rica].  

PubMed

Anadara tuberculosa is one of the most abundant mollusks of commercial importance in Costa Rica. Its habitat water is a potential source of fecal and chemical contamination to humans. We wanted to asses enterovirus, mainly poliovirus and hepatitis A virus and chemicals such as sulphates and nitrates in meat and body fluids. Thirteen samples were taken from four sites in Nicoya Gulf, three sites in the Sierpe-Térraba mangrove (Pacific of Costa Rica) and from five fish markets in San José, the capital of Costa Rica. Samples were tested for 1) fecal coliforms (Most Probable Number/100 ml), 2) isolation of enterovirus in cell culture (Hep-2, FrhK-4), 3) cell cytotoxicity in Vero cells and 4) the ability to inactivate 10 ID50% of poliovirus in cell culture. The Most Probable Number/100 ml in surrounding water was higher than the accepted standard for recreational waters, although the number of fecal coliforms in meats and body fluids was lower than in the external water. No cytopathogenic agents were isolated, but we found nitrate and sulphate concentrations that exceeded maxima for human consumption and recreation. The intrinsic cytotoxicity of the samples was at a 1/8 dilution, but some samples were cytotoxic at dilutions of 1/128. Body fluids were more cytotoxic than meats, but a positive correlation between cytotoxicity and chemical contamination was not determined: apparently other pollutants not identified in this study were responsible. Fluid and meat capacity to inactivate 10 ID50% of poliovirus in cell culture was demonstrated. Samples that were toxic for cell cultures also showed a higher percentage of poliovirus inactivation. Monitoring chemical pollution in these waters is highly recommended. PMID:10883327

Libia Herrero, U; Alejandro Palacios, F; Laya Hun, O; Francisco Vega, A

1999-09-01

161

Pyrrolidine dithiocarbamate inhibits enterovirus 71 replication by down-regulating ubiquitin-proteasome system.  

PubMed

Enterovirus 71 (EV71) is the main causative pathogen of hand, foot, and mouth disease (HFMD). The severe neurological complications caused by EV71 infection and the lack of effective therapeutic medicine underline the importance of searching for antiviral substances. Pyrrolidine dithiocarbamate (PDTC), an antioxidant, has been reported to inhibit the replication of coxsackievirus B (CVB) through dysregulating ubiquitin-proteasome system (UPS). In this study, we demonstrated that PDTC exerted potent antiviral effect on EV71. Viral RNA synthesis, viral protein expression, and the production of viral progeny were significantly reduced by the treatment of PDTC in Vero cells infected with EV71. Similar to the previous report about the inhibitory effect of PDTC on UPS, we found that PDTC treatment led to decreased levels of polyubiquitinated proteins in EV71-infected cells. The inhibitory effect of PDTC on UPS was further confirmed by the increased accumulation of cell cycle regulatory proteins p21 and p53, which are normally degraded through UPS, while the expression levels of both proteins remained unchanged. We also showed that PDTC had no impact on the activity of proteasome. Thus, we demonstrated that the down-regulation of PDTC on UPS was the result of its inhibition on ubiquitination. More importantly, this study provides evidence that the inhibition on UPS was required for the antiviral activity of PDTC, since MG132, a potent proteasome inhibitor, significantly inhibited the cytopathic effect and viral protein synthesis in EV71-infected cells. We also found that the antioxidant property of PDTC did not contribute to its antiviral effect, since N-acetyl-l-cysteine, a potent antioxidant, could not inhibit viral replication. In addition, CPE and viral protein synthesis were not inhibited in the cells pretreated with PDTC 2h before viral infection and then cultured in the media with no PDTC supplement, while the antioxidant effect of PDTC was retained. PDTC also showed significant inhibition on apoptosis induced by EV71 infection when it was applied at the early stage of viral infection. Our results collectively suggest that PDTC could be a potential anti-EV71 compound which possesses both antiviral and anti-apoptotic capacity. PMID:25456405

Lin, Lexun; Qin, Ying; Wu, Heng; Chen, Yang; Wu, Shuo; Si, Xiaoning; Wang, Hui; Wang, Tianying; Zhong, Xiaoyan; Zhai, Xia; Tong, Lei; Pan, Bo; Zhang, Fengmin; Zhong, Zhaohua; Wang, Yan; Zhao, Wenran

2015-01-01

162

Human Health Countermeasures (HHC) Element Management Plan: Human Research Program. Revision B  

NASA Technical Reports Server (NTRS)

NASA s Human Research Program (HRP) is an applied research and technology program within the Human Exploration and Operations Mission Directorate (HEOMD) that addresses human health and performance risk mitigation strategies in support of exploration missions. The HRP research and technology development is focused on the highest priority risks to crew health and safety with the goal of ensuring mission success and maintaining long-term crew health. Crew health and performance standards, defined by the NASA Chief Health and Medical Officer (CHMO), set the acceptable risk level for exploration missions. The HRP conducts research to inform these standards as well as provide deliverables, such as countermeasures, that ensure standards can be met to maximize human performance and mission success. The Human Health Countermeasures (HHC) Element was formed as part of the HRP to develop a scientifically-based, integrated approach to understanding and mitigating the health risks associated with human spaceflight. These health risks have been organized into four research portfolios that group similar or related risks. A fifth portfolio exists for managing technology developments and infrastructure projects. The HHC Element portfolios consist of: a) Vision and Cardiovascular; b) Exercise and Performance; c) Multisystem; d) Bone; and e) Technology and Infrastructure. The HHC identifies gaps associated with the health risks and plans human physiology research that will result in knowledge required to more fully understand risks and will result in validated countermeasures to mitigate risks.

Norsk, Peter; Baumann, David

2012-01-01

163

Simple method of detecting enteroviruses in contaminated molluscs and sewage by using polymerase chain reaction coupled with a colorimetric microwell detection assay  

Microsoft Academic Search

The methods normally used for the detection of enteroviruses in environmental [MM1]samples involve the use of cell cultures, which are expensive and time consuming. The Polymerase Chain Reaction (PCR) is a useful tool for the detection of enteroviruses in several matrixes because primary cell culture is not needed and the increased sensitivity of PCR allows detection of the low numbers

O. Gualillo; D. Biscardi; R. Di Carlo; R. De Fusco

1999-01-01

164

Identification and characterization of human CKTSF1B2 and CKTSF1B3 genes in silico.  

PubMed

Bone morphogenetic proteins (BMPs) are implicated in the regulation of morphogenesis and proliferation during embryogenesis and carcinogenesis. We have previously reported over-expression of BMP4 in diffuse-type gastric cancer cells. BMP signaling is regulated by tissue-specific expression of ligands and receptors as well as by secreted-type antagonists, such as CKTSF1B1 (Gremlin), CER1 (Cerberus 1), Noggin, SOSTDC1 (Ectodin), and Chordin. Here, we identified two novel genes related to CKTSF1B1 and CER1 by using bioinformatics. Two novel members of human CKTSF1B gene family were designated CKTSF1B2 (GREM2 or PRDC) and CKTSF1B3 (GREM3 or DANTE). FLJ21195 (BC046632.1) was the representative human CKTSF1B2 cDNA, and CKTSF1B2 gene was mapped to human chromosome 1q43. Human CKTSF1B2 showed 94.0% total amino-acid identity with mouse Cktsf1b2 (Prdc). FLJ38607 (AK095926.1) was the representative human CKTSF1B3 cDNA, and CKTSF1B3 gene was mapped to human chromosome 19p13.2. Human CKTSF1B3 showed 61.9% total amino-acid identity with mouse Cktsf1b2 (Dante). N-terminal signal peptide and DAN domain with nine cysteine residues were conserved among CKTSF1B1, CKTSF1B2, CKTSF1B3 and CER1. Phylogenetic analyses revealed that CKTSF1B2 was more related to CKTSF1B1, and that CKTSF1B3 was more related to CER1. CKTSF1B1, CKTSF1B2, CKTSF1B3 and CER1 constitute the CKTSF1B family among secreted-type cysteine knot superfamily proteins. This is the first report on identification and characterization of the human CKTSF1B2 and CKTSF1B3 genes. PMID:15254711

Katoh, Masuko; Katoh, Masaru

2004-08-01

165

EphB2 contributes to human naive B-cell activation and is regulated by miR-185.  

PubMed

EphB2 is an important member of the receptor tyrosine kinases. Recently, EphB2 was shown to facilitate T-cell migration and monocyte activation. However, the effects of EphB2 on B cells remain unknown. In this study, the expression of EphB2 on B cells was tested by Western blot, and the roles of EphB2 in B-cell proliferation, cytokine secretion, and immunoglobulin (Ig) production were evaluated using EphB2 siRNA interference in human B cells from healthy volunteers. Our study revealed that EphB2 was distributed on naive B cells and was up-regulated on activated B cells. Moreover, B-cell proliferation (decreased by 22%, P<0.05), TNF-? secretion (decreased by 40%, P<0.01) and IgG production (decreased by 26%, P < 0.05) were depressed concordantly with the down-regulated EphB2 expression. Subsequently, we screened microRNAs that could regulate EphB2 expression in B cells, and discovered that miR-185 directly targeted to EphB2 mRNA and suppressed its expression. Furthermore, miR-185 overexpression inhibited B-cell activation, and the inhibitor of miR-185 enhanced B-cell activation. Moreover, abatement of EphB2 through miR-185 mimics or EphB2 siRNA attenuated the activation of Src-p65 and Notch1 signaling pathways in human B cells. Our study first suggested that EphB2 was involved in human naive B cell activation through Src-p65 and Notch1 signaling pathways and could be regulated by miR-185. PMID:24803541

Yu, Miao; Liang, Wei; Wen, Shuang; Zhao, Tong; Zhu, Ming-Xin; Li, Huan-Huan; Long, Qi; Wang, Min; Cheng, Xiang; Liao, Yu-Hua; Yuan, Jing

2014-08-01

166

High-affinity interaction of hnRNP A1 with conserved RNA structural elements is required for translation and replication of enterovirus 71.  

PubMed

Human Enterovirus 71 (EV71) is an emerging pathogen of infectious disease and a serious threat to public health. Currently, there are no antivirals or vaccines to slow down or prevent EV71 infections, thus underscoring the urgency to better understand mechanisms of host-enterovirus interactions. EV71 uses a type I internal ribosome entry site (IRES) to recruit the 40S ribosomal subunit via a pathway that requires the cytoplasmic localization of hnRNP A1, which acts as an IRES trans-activating factor. The mechanism of how hnRNP A1 trans activates EV71 RNA translation is unknown, however. Here, we report that the UP1 domain of hnRNP A1 interacts specifically with stem loop II (SLII) of the IRES, via a thermodynamically well-defined biphasic transition that involves conserved bulge 5'-AYAGY-3' and hairpin 5'-RY(U/A)CCA-3' loops. Calorimetric titrations of wild-type and mutant SLII constructs reveal these structural elements are essential to form a high-affinity UP1-SLII complex. Mutations that alter the bulge and hairpin primary or secondary structures abrogate the biphasic transition and destabilize the complex. Notably, mutations within the bulge that destabilize the complex correlate with a large reduction in IRES-dependent translational activity and impair EV71 replication. Taken together, this study shows that a conserved SLII structure is necessary to form a functional hnRNP A1-IRES complex, suggesting that small molecules that target this stem loop may have novel antiviral properties. PMID:23727900

Levengood, Jeffrey D; Tolbert, Michele; Li, Mei-Ling; Tolbert, Blanton S

2013-07-01

167

High-affinity interaction of hnRNP A1 with conserved RNA structural elements is required for translation and replication of enterovirus 71  

PubMed Central

Human Enterovirus 71 (EV71) is an emerging pathogen of infectious disease and a serious threat to public health. Currently, there are no antivirals or vaccines to slow down or prevent EV71 infections, thus underscoring the urgency to better understand mechanisms of host-enterovirus interactions. EV71 uses a type I internal ribosome entry site (IRES) to recruit the 40S ribosomal subunit via a pathway that requires the cytoplasmic localization of hnRNP A1, which acts as an IRES trans-activating factor. The mechanism of how hnRNP A1 trans activates EV71 RNA translation is unknown, however. Here, we report that the UP1 domain of hnRNP A1 interacts specifically with stem loop II (SLII) of the IRES, via a thermodynamically well-defined biphasic transition that involves conserved bulge 5?-AYAGY-3? and hairpin 5?-RY(U/A)CCA-3? loops. Calorimetric titrations of wild-type and mutant SLII constructs reveal these structural elements are essential to form a high-affinity UP1-SLII complex. Mutations that alter the bulge and hairpin primary or secondary structures abrogate the biphasic transition and destabilize the complex. Notably, mutations within the bulge that destabilize the complex correlate with a large reduction in IRES-dependent translational activity and impair EV71 replication. Taken together, this study shows that a conserved SLII structure is necessary to form a functional hnRNP A1-IRES complex, suggesting that small molecules that target this stem loop may have novel antiviral properties. PMID:23727900

Levengood, Jeffrey D.; Tolbert, Michele; Li, Mei-Ling; Tolbert, Blanton S.

2013-01-01

168

A small CD11b+ human B1 cell subpopulation stimulates T cells and is expanded in lupus  

PubMed Central

A primary function of B lymphocytes is immunoglobulin production; however, the therapeutic benefit of B cell depletion in autoimmune diseases previously thought to be T cell mediated suggests that some B cells fulfill other roles in autoimmunity. We examined the recently identified human B1 cell population for T cell stimulatory activity. We found two kinds of B1 cells that are distinguished by multiple surface markers and distinct transcriptomic profiles. In both umbilical cord and adult peripheral blood, a CD11b+ subset constitutes ?1 out of every 8–10 B1 cells, whereas a CD11b? subset constitutes the remaining B1 cells. These B1 cell populations differ functionally. CD11b? B1 cells spontaneously secrete much more IgM than CD11b+ B1 cells. In contrast, CD11b+ B1 cells express more CD86, and more efficiently stimulate allogeneic CD4+ T cell expansion, than CD11b? B1 cells. The frequency of these CD11b+ B1 cells is markedly elevated in lupus patients. CD11b+ B1 cells in lupus patients express more CD86 and have increased T cell–stimulating activity in disease. This work distinguishes a novel, T cell–interacting B1 cell population whose abundance and activity may be a reflection of, and a therapeutic target in, autoimmune disease. PMID:22110167

Griffin, Daniel O.

2011-01-01

169

Viral Pollution in the Environment and in Shellfish: Human Adenovirus Detection by PCR as an Index of Human Viruses  

Microsoft Academic Search

A study of the presence of human viruses (adenoviruses, enteroviruses, and hepatitis A viruses (HAVs)) in environmental and shellfish samples was carried out by applying DNA and cDNA amplification techniques by PCR. The detection of human adenoviruses by PCR was also examined as a potential molecular test to monitor viral pollution. The samples studied were urban and slaughterhouse sewage, river

SONIA PINA; MONTSERRAT PUIG; FRANCISCO LUCENA; JOAN JOFRE; ROSINA GIRONES

1998-01-01

170

Human herpes virus 6B: a possible role in epilepsy?  

PubMed

Human herpes virus 6 (HHV6) infection is nearly ubiquitous in childhood and may include central nervous system invasion. There are two variants, HHV6A and HHV6B. Usually asymptomatic, it is associated with the common, self-limited childhood illness roseola infantum and rarely with more severe syndromes. In patients with immune compromise, subsequent reactivation of viral activity may lead to severe limbic encephalitis. HHV6 has been identified as a possible etiologic agent in multiple sclerosis, myocarditis, and encephalitis. A preponderance of evidence supports an association between HHV6 and febrile seizures. An ongoing multicenter study is investigating possible links between HHV6 infection, febrile status epilepticus, and development of mesial temporal sclerosis (MTS). Investigation of temporal lobectomy specimens showed evidence of active HHV6B but not HHV6A replication in hippocampal astrocytes in about two-thirds of patients with MTS but not other causes of epilepsy. It has been suggested that HHV6B may cause "excitotoxicity" by interfering with astrocyte excitatory amino acid transport. Although conventional inflammatory changes are not found in most MTS specimens, inflammatory modulators may play a role in neuronal injury leading to MTS as well. If the link between early viral infection, complex or prolonged febrile seizures, and later development of intractable temporal lobe epilepsy is confirmed, new therapeutic approaches to a common intractable epilepsy syndrome may be possible. PMID:18627418

Theodore, William H; Epstein, Leon; Gaillard, William D; Shinnar, Shlomo; Wainwright, Mark S; Jacobson, Steven

2008-11-01

171

Infectivity assays of human rhinovirus-A and -B serotypes.  

PubMed

Infectivity is a fundamental property of viral pathogens such as human rhinoviruses (HRVs). This chapter describes two methods for measuring the infectivity of HRV-A and -B serotypes: end point dilution (TCID50) assay and plaque assay. End point dilution assay is a quantal, not quantitative, assay that determines the dilution of the sample at which 50 % of the aliquots have infectious virus. It can be used for all the HRV-A and -B serotypes and related clinical isolates that grow in cell culture and induce cytopathic effect (CPE), degenerative changes in cells that are visible under a microscope. Plaque assay is a quantitative assay that determines the number of infectious units of a virus in a sample. After an infectious unit of virus infects one cell, the infected cell produces progeny viruses that then infect and kill a circle of adjacent cells. This circle of dead cells detaches from the dish and thus leaves a clear hole in a cell monolayer. Plaque assay works only for HeLa-adapted HRV-A and -B serotypes that can make visible plaques on the cell monolayer. Currently the end point dilution assay and plaque assay have not been developed for the newly discovered HRV-C. PMID:25261308

Lee, Wai-Ming; Chen, Yin; Wang, Wensheng; Mosser, Anne

2015-01-01

172

Molecular Cell Human LSD2/KDM1b/AOF1 Regulates  

E-print Network

Molecular Cell Article Human LSD2/KDM1b/AOF1 Regulates Gene Transcription by Modulating Intragenic to the regulation of transcriptional initiation. We now show that human LSD2/KDM1b/AOF1, the human homolog of LSD1 regions of its target genes. Genome-wide mapping reveals that LSD2 associates predominantly with the gene

Yuan, Guo-Cheng "GC"

173

Sporadic isolation of sabin-like polioviruses and high-level detection of non-polio enteroviruses during sewage surveillance in seven Italian cities, after several years of inactivated poliovirus vaccination.  

PubMed

Sewage surveillance in seven Italian cities between 2005 and 2008, after the introduction of inactivated poliovirus vaccination (IPV) in 2002, showed rare polioviruses, none that were wild-type or circulating vaccine-derived poliovirus (cVDPV), and many other enteroviruses among 1,392 samples analyzed. Two of five polioviruses (PV) detected were Sabin-like PV2 and three PV3, based on enzyme-linked immunosorbent assay (ELISA) and PCR results. Neurovirulence-related mutations were found in the 5'noncoding region (5'NCR) of all strains and, for a PV2, also in VP1 region 143 (Ile>Thr). Intertypic recombination in the 3D region was detected in a second PV2 (Sabin 2/Sabin 1) and a PV3 (Sabin 3/Sabin 2). The low mutation rate in VP1 for all PVs suggests limited interhuman virus passages, consistent with efficient polio immunization in Italy. Nonetheless, these findings highlight the risk of wild or Sabin poliovirus reintroduction from abroad. Non-polio enteroviruses (NPEVs) were detected, 448 of which were coxsackievirus B (CVB) and 294 of which were echoviruses (Echo). Fifty-six NPEVs failing serological typing were characterized by sequencing the VP1 region (nucleotides [nt] 2628 to 2976). A total of 448 CVB and 294 Echo strains were identified; among those strains, CVB2, CVB5, and Echo 11 predominated. Environmental CVB5 and CVB2 strains from this study showed high sequence identity with GenBank global strains. The high similarity between environmental NPEVs and clinical strains from the same areas of Italy and the same periods indicates that environmental strains reflect the viruses circulating in the population and highlights the potential risk of inefficient wastewater treatments. This study confirmed that sewage surveillance can be more sensitive than acute flaccid paralysis (AFP) surveillance in monitoring silent poliovirus circulation in the population as well as the suitability of molecular approaches to enterovirus typing. PMID:24814793

Battistone, A; Buttinelli, G; Fiore, S; Amato, C; Bonomo, P; Patti, A M; Vulcano, A; Barbi, M; Binda, S; Pellegrinelli, L; Tanzi, M L; Affanni, P; Castiglia, P; Germinario, C; Mercurio, P; Cicala, A; Triassi, M; Pennino, F; Fiore, L

2014-08-01

174

Sporadic Isolation of Sabin-Like Polioviruses and High-Level Detection of Non-Polio Enteroviruses during Sewage Surveillance in Seven Italian Cities, after Several Years of Inactivated Poliovirus Vaccination  

PubMed Central

Sewage surveillance in seven Italian cities between 2005 and 2008, after the introduction of inactivated poliovirus vaccination (IPV) in 2002, showed rare polioviruses, none that were wild-type or circulating vaccine-derived poliovirus (cVDPV), and many other enteroviruses among 1,392 samples analyzed. Two of five polioviruses (PV) detected were Sabin-like PV2 and three PV3, based on enzyme-linked immunosorbent assay (ELISA) and PCR results. Neurovirulence-related mutations were found in the 5? noncoding region (5?NCR) of all strains and, for a PV2, also in VP1 region 143 (Ile > Thr). Intertypic recombination in the 3D region was detected in a second PV2 (Sabin 2/Sabin 1) and a PV3 (Sabin 3/Sabin 2). The low mutation rate in VP1 for all PVs suggests limited interhuman virus passages, consistent with efficient polio immunization in Italy. Nonetheless, these findings highlight the risk of wild or Sabin poliovirus reintroduction from abroad. Non-polio enteroviruses (NPEVs) were detected, 448 of which were coxsackievirus B (CVB) and 294 of which were echoviruses (Echo). Fifty-six NPEVs failing serological typing were characterized by sequencing the VP1 region (nucleotides [nt] 2628 to 2976). A total of 448 CVB and 294 Echo strains were identified; among those strains, CVB2, CVB5, and Echo 11 predominated. Environmental CVB5 and CVB2 strains from this study showed high sequence identity with GenBank global strains. The high similarity between environmental NPEVs and clinical strains from the same areas of Italy and the same periods indicates that environmental strains reflect the viruses circulating in the population and highlights the potential risk of inefficient wastewater treatments. This study confirmed that sewage surveillance can be more sensitive than acute flaccid paralysis (AFP) surveillance in monitoring silent poliovirus circulation in the population as well as the suitability of molecular approaches to enterovirus typing. PMID:24814793

Battistone, A.; Buttinelli, G.; Fiore, S.; Amato, C.; Bonomo, P.; Patti, A. M.; Vulcano, A.; Barbi, M.; Binda, S.; Pellegrinelli, L.; Tanzi, M. L.; Affanni, P.; Castiglia, P.; Germinario, C.; Mercurio, P.; Cicala, A.; Triassi, M.; Pennino, F.

2014-01-01

175

Electrostatic Regulation of Genome Packaging in Human Hepatitis B Virus Zhen-Gang Wang,  

E-print Network

Electrostatic Regulation of Genome Packaging in Human Hepatitis B Virus Tao Jiang, Zhen-Gang Wang, California ABSTRACT Hepatitis B virus (HBV) is a contagious human pathogen causing liver diseases-termini. INTRODUCTION Hepatitis B virus (HBV) is a pararetrovirus responsible for up to 80% of all cases

Wu, Jianzhong

176

The Immune Response to Hepatitis B Vaccine in Humans: Inheritance Patterns in Families  

E-print Network

The Immune Response to Hepatitis B Vaccine in Humans: Inheritance Patterns in Families By Margot S haverecently shown that the human antibody response to the hepatitis B virus surface antigen (HBs immunized with the hepatitis B vaccine, including sevenfamilies where at least one member bore the haplotype

Alper, Chester A.

177

Human blood IgM "memory" B cells are circulating splenic marginal zone B cells harboring a prediversified immunoglobulin repertoire  

E-print Network

Human blood IgM "memory" B cells are circulating splenic marginal zone B cells harboring cell subsets, that blood IgM IgD CD27 cells correspond to circulating splenic marginal zone B cells and Cell Biology10 University of Marburg, DE G n tique Humaine des Maladies Infectieuses11 é é INSERM : U

Boyer, Edmond

178

Interferon-? inhibits group B Streptococcus survival within human endothelial cells  

PubMed Central

Endothelial dysfunction is a major component of the pathophysiology of septicaemic group B Streptococcus (GBS) infections. Although cytokines have been shown to activate human umbilical vein endothelial cells (HUVECs), the capacity of interferon (IFN)-? to enhance the microbicidal activity of HUVECs against GBS has not been studied. We report that the viability of intracellular bacteria was reduced in HUVECs activated by IFN-?. Enhanced fusion of lysosomes with bacteria-containing vacuoles was observed by acid phosphatase and the colocalisation of Rab-5, Rab-7 and lysosomal-associated membrane protein-1 with GBS in IFN-?-activated HUVECs. IFN-? resulted in an enhancement of the phagosome maturation process in HUVECs, improving the capacity to control the intracellular survival of GBS. PMID:25410999

Lione, Viviane de Oliveira Freitas; dos Santos, Michelle Hanthequeste Bittencourt; de Oliveira, Jessica Silva Santos; Mattos-Guaraldi, Ana Luiza; Nagao, Prescilla Emy

2014-01-01

179

Detection of Astroviruses, Enteroviruses, and Adenovirus Types 40 and 41 in Surface Waters Collected and Evaluated by the Information Collection Rule and an Integrated Cell Culture-Nested PCR Procedure  

PubMed Central

We evaluated the use of an integrated cell culture-reverse transcription-PCR (ICC-RT-PCR) procedure coupled with nested PCR to detect human astroviruses, enteroviruses, and adenovirus types 40 and 41 in surface water samples that were collected and evaluated by using the Information Collection Rule (ICR) method. The results obtained with the ICC-RT-PCR–nested PCR method were compared to the results obtained with the total culturable virus assay–most-probable-number (TCVA-MPN) method, the method recommended by the U.S. Environmental Protection Agency for monitoring viruses in surface and finished waters. Twenty-nine ICR surface water samples were analyzed. Viruses were concentrated by using filter adsorption-beef extract elution and organic flocculation techniques, and then the preparations were evaluated for viruses by visualizing cytopathic effects in the Buffalo green monkey kidney (BGMK) cell line. In the ICC-RT-PCR–nested PCR technique we used Caco-2 cells to propagate astroviruses and enteroviruses (ICC step), and we used BGMK cells to propagate adenovirus types 40 and 41, as well as enteroviruses. Fifteen of the 29 samples (51.7%) were positive for astrovirus as determined by the ICC-RT-PCR–nested PCR method, and eight of these samples (27.5%) contained infectious astrovirus. Seventeen of the 29 samples (58.6%) were positive for enteroviruses when the BGMK cell line was used, and six (27.6%) of these samples were determined to be infectious. Fourteen of the 29 samples (48.3%) were positive for adenovirus types 40 and 41, and 11 (37.9%) of these samples were determined to be infectious. Twenty-seven of the 29 samples (93.1%) were positive for a virus, and 19 (68.9%) of the samples were positive for an infectious virus. Only 5 of the 29 samples (17.2%) were positive as determined by the TCVA-MPN method. The ICC-RT-PCR–nested PCR method provided increased sensitivity compared to the TCVA-MPN method. PMID:10831432

Chapron, Christopher D.; Ballester, Nicola A.; Fontaine, Justin H.; Frades, Christine N.; Margolin, Aaron B.

2000-01-01

180

Human SCARB2-Mediated Entry and Endocytosis of EV71  

PubMed Central

Enterovirus (EV) 71 infection is known to cause hand-foot-and-mouth disease (HFMD) and in severe cases, induces neurological disorders culminating in fatality. An outbreak of EV71 in South East Asia in 1997 affected over 120,000 people and caused neurological disorders in a few individuals. The control of EV71 infection through public health interventions remains minimal and treatments are only symptomatic. Recently, human scavenger receptor class B, member 2 (SCARB2) has been reported to be a cellular receptor of EV71. We expressed human SCARB2 gene in NIH3T3 cells (3T3-SCARB2) to study the mechanisms of EV71 entry and infection. We demonstrated that human SCARB2 serves as a cellular receptor for EV71 entry. Disruption of expression of SCARB2 using siRNAs can interfere EV71 infection and subsequent inhibit the expression of viral capsid proteins in RD and 3T3-SCARB2 but not Vero cells. SiRNAs specific to clathrin or dynamin or chemical inhibitor of clathrin-mediated endocytosis were all capable of interfering with the entry of EV71 into 3T3-SCARB2 cells. On the other hand, caveolin specific siRNA or inhibitors of caveolae-mediated endocytosis had no effect, confirming that only clathrin-mediated pathway was involved in EV71 infection. Endocytosis of EV71 was also found to be pH-dependent requiring endosomal acidification and also required intact membrane cholesterol. In summary, the mechanism of EV71 entry through SCARB2 as the receptor for attachment, and its cellular entry is through a clathrin-mediated and pH-dependent endocytic pathway. This study on the receptor and endocytic mechanisms of EV71 infection is useful for the development of effective medications and prophylactic treatment against the enterovirus. PMID:22272359

Tsou, Yueh-Liang; Chitra, Ebenezer; Hsiao, Kuang-Nan; Shao, Hsiao-Yun; Liu, Chia-Chyi; Sia, Charles; Chong, Pele; Chow, Yen-Hung

2012-01-01

181

Human SCARB2-mediated entry and endocytosis of EV71.  

PubMed

Enterovirus (EV) 71 infection is known to cause hand-foot-and-mouth disease (HFMD) and in severe cases, induces neurological disorders culminating in fatality. An outbreak of EV71 in South East Asia in 1997 affected over 120,000 people and caused neurological disorders in a few individuals. The control of EV71 infection through public health interventions remains minimal and treatments are only symptomatic. Recently, human scavenger receptor class B, member 2 (SCARB2) has been reported to be a cellular receptor of EV71. We expressed human SCARB2 gene in NIH3T3 cells (3T3-SCARB2) to study the mechanisms of EV71 entry and infection. We demonstrated that human SCARB2 serves as a cellular receptor for EV71 entry. Disruption of expression of SCARB2 using siRNAs can interfere EV71 infection and subsequent inhibit the expression of viral capsid proteins in RD and 3T3-SCARB2 but not Vero cells. SiRNAs specific to clathrin or dynamin or chemical inhibitor of clathrin-mediated endocytosis were all capable of interfering with the entry of EV71 into 3T3-SCARB2 cells. On the other hand, caveolin specific siRNA or inhibitors of caveolae-mediated endocytosis had no effect, confirming that only clathrin-mediated pathway was involved in EV71 infection. Endocytosis of EV71 was also found to be pH-dependent requiring endosomal acidification and also required intact membrane cholesterol. In summary, the mechanism of EV71 entry through SCARB2 as the receptor for attachment, and its cellular entry is through a clathrin-mediated and pH-dependent endocytic pathway. This study on the receptor and endocytic mechanisms of EV71 infection is useful for the development of effective medications and prophylactic treatment against the enterovirus. PMID:22272359

Lin, Yi-Wen; Lin, Hsiang-Yin; Tsou, Yueh-Liang; Chitra, Ebenezer; Hsiao, Kuang-Nan; Shao, Hsiao-Yun; Liu, Chia-Chyi; Sia, Charles; Chong, Pele; Chow, Yen-Hung

2012-01-01

182

The Human Leukocyte Antigen–presented Ligandome of B Lymphocytes*  

PubMed Central

Peptides presented by human leukocyte antigen (HLA) molecules on the cell surface play a crucial role in adaptive immunology, mediating the communication between T cells and antigen presenting cells. Knowledge of these peptides is of pivotal importance in fundamental studies of T cell action and in cellular immunotherapy and transplantation. In this paper we present the in-depth identification and relative quantification of 14,500 peptide ligands constituting the HLA ligandome of B cells. This large number of identified ligands provides general insight into the presented peptide repertoire and antigen presentation. Our uniquely large set of HLA ligands allowed us to characterize in detail the peptides constituting the ligandome in terms of relative abundance, peptide length distribution, physicochemical properties, binding affinity to the HLA molecule, and presence of post-translational modifications. The presented B-lymphocyte ligandome is shown to be a rich source of information by the presence of minor histocompatibility antigens, virus-derived epitopes, and post-translationally modified HLA ligands, and it can be a good starting point for solving a wealth of specific immunological questions. These HLA ligands can form the basis for reversed immunology approaches to identify T cell epitopes based not on in silico predictions but on the bona fide eluted HLA ligandome. PMID:23481700

Hassan, Chopie; Kester, Michel G. D.; de Ru, Arnoud H.; Hombrink, Pleun; Drijfhout, Jan Wouter; Nijveen, Harm; Leunissen, Jack A. M.; Heemskerk, Mirjam H. M.; Falkenburg, J. H. Frederik; van Veelen, Peter A.

2013-01-01

183

Organometallic B12-DNA conjugate: synthesis, structure analysis, and studies of binding to human B12-transporter proteins.  

PubMed

Design, synthesis, and structural characterization of a B12-octadecanucleotide are presented herein, a new organometallic B12-DNA conjugate. In such covalent conjugates, the natural B12 moiety may be a versatile vector for controlled in vivo delivery of oligonucleotides to cellular targets in humans and animals, through the endogenous B12 transport systems. Binding of the organometallic B12 octadecanucleotide to the three important human proteins of B12 transport was studied, to examine its structural suitability for the task of eventual in vivo oligonucleotide delivery. Binding was efficient with transcobalamin (TC), but not so efficient with the homologous glycoproteins intrinsic factor and haptocorrin. Binding of the B12 octadecanucleotide to TC suggests the capacity of the B12 moiety to serve as a natural vector for specific transport of single stranded, organometallic oligonucleotide loads from the blood stream into cells. PMID:25168390

Hunger, Miriam; Mutti, Elena; Rieder, Alexander; Enders, Barbara; Nexo, Ebba; Kräutler, Bernhard

2014-10-01

184

Human bradykinin B2 receptor: Nucleotide sequence analysis and assignment to chromosome 14  

Microsoft Academic Search

Functional cDNA clones for human bradykinin B2 receptor were isolated from uterus RNA by a polymerase chain reaction (PCR)-based method and by screening a human cosmid library with rat bradykinin B2 receptor probe. We isolated several overlapping clones from the cosmid library, each of which encodes the entire protein-coding sequence. The human bradykinin B2 receptor gene codes for a 364-amino-acid

S. J. Powell; G. Slynn; C. Thomas; B. Hopkins; I. Briggs; A. Graham

1993-01-01

185

Leukotriene B4 activates intracellular calcium and augments human osteoclastogenesis.  

PubMed

IntroductionBone erosion in inflammatory arthritis depends on the recruitment and activation of bone resorbing cells, the osteoclasts. Interleukin-23 (IL-23) has been primarily implicated in mediating inflammatory bone loss via the differentiation of Th17 receptor activator of nuclear factor kappa-B ligand (RANKL)-producing cells. In this manuscript we describe a new role of IL-23 in activating the synthesis and production of leukotriene B4 (LTB4) in innate immune cells.MethodsWe utilized whole blood derived human peripheral blood mononuclear cells (PBMCs), differentiated them towards an osteoclast lineage and then performed immunofluorescence and cytochemical staining to detect the expression of LTB4 associated receptors, enzymes such as phospholipase A2, 5-lipoxygenase and leukotriene A4 hydrolase, the presence of tartrate-resistant acid phosphatase (TRAP) and F-actin rings on fully mature osteoclasts. We used enzyme immunoassay to measure LTB4 levels in culture media derived from IL-23 treated human PBMCs. We used real time calcium imaging to study the effect of leukotrienes and requirements of different calcium sources and signaling proteins in activating intracellular calcium flux using pharmacological inhibitors to phospholipase C (U73122), membrane calcium channels (2-APB) and phosphatidylinositol 3-kinase (Wortmannin) and utilized qPCR for gene expression analysis in macrophages and osteoclasts.ResultsOur data shows that LTB4 engagement of BLT1 and BLT2 receptors on osteoclast precursors leads to activation of phospholipase C and calcium release activated channel mediated intracellular calcium flux, which can activate further LTB4 autocrine production. IL-23-induced synthesis and secretion of LTB4 resulted in the upregulation of osteoclast related genes NFATC1, MMP9, ACP5, CTSK and ITGB3 and the formation of giant, multi-nucleated TRAP+ cells capable of F-actin ring formation. These effects were dependent on Ca2+ signaling and were completely inhibited by BLT1/2 and/or PLC and CRAC inhibitors.ConclusionsIn conclusion, IL-23 can initiate osteoclast differentiation independently from the RANK-RANKL pathway by utilizing Ca2+ signaling and the leukotriene B4 signaling cascade. PMID:25443625

Dixit, Neha; Wu, Dennis J; Belgacem, Yesser H; Borodinsky, Laura N; Gershwin, M; Adamopoulos, Iannis E

2014-12-01

186

Gene expression analysis of primary normal human hepatocytes infected with human hepatitis B virus  

PubMed Central

AIM: To find the relationship between hepatitis B virus (HBV) and hepatocytes during the initial state of infection by cDNA microarray. METHODS: Primary normal human hepatocytes (PNHHs) were isolated and infected with HBV. From the PNHHs, RNA was isolated and inverted into complement DNA (cDNA) with Cy3- or Cy5- labeled dUTP for microarray analysis. The labeled cDNA was hybridized with microarray chip, including 4224 cDNAs. From the image of the microarray, expression profiles were produced and some of them were confirmed by RT-PCR, immunoblot analysis, and NF-?B luciferase reporter assay. RESULTS: From the cDNA microarray, we obtained 98 differentially regulated genes. Of the 98 genes, 53 were up regulated and 45 down regulated. Interestingly, in the up regulated genes, we found the TNF signaling pathway-related genes: LT-?, TRAF2, and NIK. By using RT-PCR, we confirmed the up-regulation of these genes in HepG2, Huh7, and Chang liver cells, which were transfected with pHBV1.2×, a plasmid encoding all HBV messages. Moreover, these three genes participated in HBV-mediated NF-?B activation. CONCLUSION: During the initial state of HBV infection, hepatocytes facilitate the activation of NF-?B through up regulation of LT-?, TRAF2, and NIK. PMID:16937494

Ryu, Hyun Mi; Park, Sung Gyoo; Yea, Sung Su; Jang, Won Hee; Yang, Young-Il; Jung, Guhung

2006-01-01

187

HUMAN CYTOSOLIC SULFOTRANSFERASE 2B1: ISOFORM EXPRESSION, TISSUE SPECIFICITY AND SUBCELLULAR LOCALIZATION  

PubMed Central

Sulfation is an important Phase II conjugation reaction involved in the synthesis and metabolism of steroids in humans. Two different isoforms (2B1a and 2B1b) are encoded by the sulfotransferase (SULT) 2B1 gene utilizing different start sites of transcription resulting in the incorporation of different first exons. SULT2B1a and SULT2B1b are 350 and 365 amino acids in length, respectively, and the last 342 aa are identical. Message for both SULT2B1 isoforms is present in human tissues although SULT2B1b message is generally more abundant. However, to date only SULT2B1b protein has been detected in human tissues or cell lines. SULT2B1b is localized in the cytosol and/or nuclei of human cells. A unique 3?-extension of SULT2B1b is required for nuclear localization in human BeWo placental choriocarcinoma cells. Nuclear localization is stimulated by forskolin treatment in BeWo cells and serine phosphorylation has been identified in the 3?-extension. SULT2B1b is selective for the sulfation of 3?-hydroxysteroids such as dehydroepiandrosterone and pregnenolone, and may also have a role in cholesterol sulfation in human skin. The substrate specificity, nuclear localization, and tissue localization of SULT2B1b suggest a role in regulating the responsiveness of cells to adrenal androgens via their direct inactivation or by preventing their conversion to more potent androgens and estrogens. PMID:17055258

Falany, C.N.; He, D.; Dumas, N.; Frost, A.R.; Falany, J.L.

2007-01-01

188

Epidemiological, molecular and clinical features of Enterovirus 109 infection in children and in adult stem cell transplant recipients  

PubMed Central

Background A novel human enterovirus (HEV) type within the species HEV-C, named EV109, was discovered from cases of respiratory illness in Nicaragua in September 2010. The aim of this study, was to retrospectively examine the presence and the role of EV109 in respiratory samples from two patients populations; infants below the age of 2?years, hospitalized for acute respiratory diseases (ARDs) and adult hematopoietic stem cell transplantation recipients. Results A total of 1149 nasopharingeal aspirates were collected and tested for the presence of EV109 by reverse transcription-PCR (RT-PCR). In positive samples, the presence of the most common respiratory viruses was also assayed and clinical symptoms were evaluated. Samples from 2 of the 974 infants tested positive for EV109 RNA (0.2%) and belonged to patients with lower ARDs; co-infection with other viral pathogens under study was observed in both cases. In transplant recipients, one out of the 175 samples analyzed, from a patients with upper respiratory simptoms tested positive for HEV 109 in the absence of co-infecting viruses. Sequence analysis of amplified EV109 genomic regions, showed only a few nucleotide differences when compared with the Nicaraguan strains. Conclusions Overall these results indicate that HEV109 variants have circulated and differentiated in different lineages worldwide. Although more cases and larger studies are needed, HEV109 infection may be associated to ARDs both in infants and in hematopoietic stem cell transplantation recipients. If these preliminary observations will be confirmed, improved molecular methods with a wider panel of potential pathogens will be useful for monitoring these categories of patients. PMID:22947270

2012-01-01

189

Human regulatory B cells combine phenotypic and genetic hallmarks with a distinct differentiation fate.  

PubMed

Regulatory B cells (B-reg) produce IL-10 and suppress inflammation in both mice and humans, but limited data on the phenotype and function of these cells have precluded detailed assessment of their contribution to host immunity. In this article, we report that human B-reg cannot be defined based on a phenotype composed of conventional B cell markers, and that IL-10 production can be elicited in both the CD27(+) memory population and naive B cell subset after only a brief stimulation in vitro. We therefore sought to obtain a better definition of IL-10-producing human B-regs using a multiparameter analysis of B cell phenotype, function, and gene expression profile. Exposure to CpG and anti-Ig are the most potent stimuli for IL-10 secretion in human B cells, but microarray analysis revealed that human B cells cotreated with these reagents resulted in only ?0.7% of genes being differentially expressed between IL-10(+) and IL-10(-) cells. Instead, connectivity map analysis revealed that IL-10-secreting B cells are those undergoing specific differentiation toward a germinal center fate, and we identified a CD11c(+) B cell subset that was not capable of producing IL-10 even under optimal conditions. Our findings will assist in the identification of a broader range of human pro-B-reg populations that may represent novel targets for immunotherapy. PMID:25080484

Lin, Wenyu; Cerny, Daniela; Chua, Edmond; Duan, Kaibo; Yi, June Tai Jing; Shadan, Nurhidaya Binte; Lum, Josephine; Maho-Vaillant, Maud; Zolezzi, Francesca; Wong, Siew Cheng; Larbi, Anis; Fink, Katja; Musette, Philippe; Poidinger, Michael; Calbo, Sébastien

2014-09-01

190

Outbreaks of hand, foot, and mouth disease by enterovirus 71. High incidence of complication disorders of central nervous system  

Microsoft Academic Search

In Japan we have had two outbreaks of hand, foot, and mouth disease associated with disorders of the central nervous system, one in 1973 and the other in 1978. The isolated virus in both outbreaks was enterovirus 71. Central nervous system disorders were present in 24% of patients in 1973 and in 8% of patients in 1978. These disorders were

Y Ishimaru; S Nakano; K Yamaoka; S Takami

1980-01-01

191

Complementation of apolipoprotein B mRNA editing by human liver accompanied by secretion of apolipoprotein B48.  

PubMed

Mammalian small intestine secretes a truncated apolipoprotein B (apoB48) species as a result of tissue-specific post-transcriptional RNA editing. The human liver, by contrast, contains only unedited apoB mRNA and secretes only apoB100. We have recently isolated a cDNA clone from rat small intestine which encodes an apoB mRNA editing protein, REPR (Teng, B., Burant, C.F., and Davidson, N.O. (1993) Science 260, 1816-1819). The current study demonstrates that homogenates of Xenopus oocytes expressing REPR confer editing ability upon S100 extracts prepared from human liver when tested on a synthetic apoB RNA template in vitro. Transfection of REPR into HepG2 cells resulted in editing of endogenous apoB mRNA and the appearance of an apoB48-like protein in the media. Extracts prepared from these transfected cells edit mammalian apoB RNA templates when incubated alone and with enhanced efficiency in the presence of chicken intestinal S100 extracts. The results suggest that human liver expresses factor(s) which are critical to apoB mRNA editing and which allow functional complementation of REPR in vivo. PMID:8119937

Giannoni, F; Bonen, D K; Funahashi, T; Hadjiagapiou, C; Burant, C F; Davidson, N O

1994-02-25

192

Characterization of an Enterovirus species E isolated from naturally infected bovine in China.  

PubMed

Bovine enteroviruses, which belong to the Picornaviridae family, can cause clinical symptoms in cattle and are excreted in feces. In this study, a cytolytic virus was isolated from Madin-Darby bovine kidney (MDBK) cells from fecal samples of bovine with severe diarrhea and hemorrhagic intestinal mucosa that had been originally diagnosed with bovine viral diarrhea (BVD) by a bovine viral diarrhea virus Ag point-of-care test (IDEXX, American). Random priming PCR was used to amplify underlying viral sequences and identify the isolated virus. Phylogenetic analysis indicated that the isolated virus closely matches the EV-E2 species, which is different from other Chinese strains previously isolated. The newly identified virus was named HLJ-3531/2013. We infected the sulking mice with the isolated virus. Reverse-transcription PCR, hematoxylin and eosin (HE) staining, serum neutralization (SN) test, and virus isolation from various tissues revealed that HLJ-3531/2013 can infect the intestine, liver, and lung of suckling mice. The present work is the first to report the reproduction of clinical symptoms by an isolated virus in an experimental infection model of animals and lays a solid foundation for the development of the pathogenesis of bovine enteroviruses. PMID:25102330

Zhang, Haili; Liu, Hongtao; Bao, Jun; Guo, Yongli; Peng, Tongquan; Zhou, Pingping; Zhang, Wenlong; Ma, Bo; Wang, Junwei; Gao, Mingchun

2014-10-13

193

Expression and immunogenicity of novel subunit enterovirus 71 VP1 antigens  

SciTech Connect

Highlights: Black-Right-Pointing-Pointer EV71 is a major emerging infectious disease in many Asian countries. Black-Right-Pointing-Pointer Inactivated EV71 vaccines are in clinical studies but their safety and efficacy are unknown. Black-Right-Pointing-Pointer Developing subunit based EV71 vaccines is significant and novel antigen design is needed. Black-Right-Pointing-Pointer DNA immunization is an efficient tool to test the immunogenicity of VP1 based EV71 vaccines. Black-Right-Pointing-Pointer Multiple VP1 antigens are developed showing immunogenic potential. -- Abstract: Hand, foot, and mouth disease (HFMD) is a common viral illness in young children. HFMD is caused by viruses belonging to the enterovirus genus of the picornavirus family. Recently, enterovirus 71 (EV71) has emerged as a virulent agent for HFMD with severe clinical outcomes. In the current report, we conducted a pilot antigen engineering study to optimize the expression and immunogenicity of subunit VP1 antigen for the design of EV71 vaccines. DNA immunization was adopted as a simple technical approach to test different designs of VP1 antigens without the need to express VP1 protein in vitro first. Our studies indicated that the expression and immunogenicity of VP1 protein can be improved with alternated VP1 antigen designs. Data presented in the current report revealed novel pathways to optimize the design of VP1 antigen-based EV71 vaccines.

Xu, Juan [China-US Vaccine Research Center, The First Affiliated Hospital, Nanjing Medical University (China) [China-US Vaccine Research Center, The First Affiliated Hospital, Nanjing Medical University (China); Department of Microbiology and Immunology, Nanjing Medical University (China); Wang, Shixia [China-US Vaccine Research Center, The First Affiliated Hospital, Nanjing Medical University (China) [China-US Vaccine Research Center, The First Affiliated Hospital, Nanjing Medical University (China); Department of Medicine, University of Massachusetts Medical School (United States); Gan, Weihua [Department of Pediatrics, The Second Affiliated Hospital, Nanjing Medical University (China)] [Department of Pediatrics, The Second Affiliated Hospital, Nanjing Medical University (China); Zhang, Wenhong [Department of Infectious Diseases, Huashan Hospital, Fudan University (China)] [Department of Infectious Diseases, Huashan Hospital, Fudan University (China); Ju, Liwen [School of Public Health, Fudan University (China)] [School of Public Health, Fudan University (China); Huang, Zuhu [Department of Infectious Diseases, The First Affiliated Hospital, Nanjing Medical University (China) [Department of Infectious Diseases, The First Affiliated Hospital, Nanjing Medical University (China); China-US Vaccine Research Center, The First Affiliated Hospital, Nanjing Medical University (China); Lu, Shan, E-mail: shan.lu@umassmed.edu [Department of Infectious Diseases, The First Affiliated Hospital, Nanjing Medical University (China) [Department of Infectious Diseases, The First Affiliated Hospital, Nanjing Medical University (China); China-US Vaccine Research Center, The First Affiliated Hospital, Nanjing Medical University (China); Department of Medicine, University of Massachusetts Medical School (United States)

2012-04-20

194

Evaluation of monovalent and bivalent vaccines against lethal Enterovirus 71 and Coxsackievirus A16 infection in newborn mice.  

PubMed

Enterovirus 71 (EV71) and Coxsackievirus A16 (CVA16) have caused severe epidemics of hand, foot and mouth disease (HFMD) in the Asia Pacific in recent years, particularly in infants and young children. This disease has become a serious public health problem, as no vaccines or antiviral drugs have been approved for EV71 and CA16 infections. In this study, we compared four monovalent vaccines, including formalin-inactivated EV71 virus (iEV71), EV71 virus-like particles (VLPs) (vEV71), formalin-inactivated CVA16 virus (iCVA16) and CVA16 VLPs (vCVA16), along with two bivalent vaccines, including equivalent doses of formalin-inactivated EV71+CVA16 virus (iEV71+iCVA16) and EV71+CVA16 VLPs (vEV71+vCVA16). The IgG titers and neutralization antibodies titers demonstrated that there are no immune interference exists between the two immunogens of EV71 and CVA16. IgG subclass isotyping revealed that IgG1 and IgG2b were induced primarily in all vaccine groups. Furthermore, cross-neutralization antibodies were elicited in mouse sera against other sub-genotypes of EV71 and CVA16. In vivo challenge experiments showed that the immune sera from vaccinated animals could confer passive protection to newborn mice against lethal challenge with 14 LD50 of EV71 and 50 LD50 of CVA16. Our results indicated that bivalent vaccination is promising for HFMD vaccine development. With the advantage of having a better safety profile than inactivated virus vaccines, VLPs should be used to combine both EV71 and CVA16 antigens as a candidate vaccine for prevention of HFMD virus transmission. PMID:25483672

Sun, Shiyang; Jiang, Liping; Liang, Zhenglun; Mao, Qunying; Su, Weiheng; Zhang, Huafei; Li, Xiaojun; Jin, Jun; Xu, Lin; Zhao, Dandan; Fan, Peihu; An, Dong; Yang, Ping; Lu, Jingcai; Lv, Xiuping; Sun, Bo; Xu, Fei; Kong, Wei; Jiang, Chunlai

2014-08-21

195

Isolation and chromosomal mapping of the human immunoglobulin-associated B29 gene (IGB)  

SciTech Connect

The B29 gene encodes a B-cell-specific membrane protein in the immunoglobulin antigen receptor complex. B29 is a crucial member of this receptor complex and is believed to function as an effector of signal transduction in a manner analogous to that of the CD3 components of the T cell antigen receptor. The authors have isolated a full-length human B29 cDNA clone by using a murine B29 cDNA probe. They show that there is an extremely high degree of evolutionary conservation between the human and mouse proteins, particularly in the transmembrane and intracytoplasmic regions, where the identity is 96%. In addition, the intracytoplasmic region in both proteins contains an identical peptide motif that is present in a number of molecules involved in lymphocyte activation. Genomic Southern blot analysis of human cell lines hybridized with both murine and human B29 cDNAs gives patterns consistent with a single-copy gene occupying a small region of the genomic sequence. Using human B29 cosmid DNA, they have localized the B29 gene to human chromosome 17q23 via fluorescence in situ hybridization. B29 is the first gene localized to this area of the genome. Interestingly, a subset of human B cell chronic lymphocytic leukemias (CLL) has translocations in this locus on chromosome 17. 18 refs., 4 figs.

Wood, W.J. Jr.; Thompson, A.A.; Korenberg, J.; Xianing Chen; May, W.; Wall, R.; Denny, C.T. (Univ. of California, Los Angeles (United States))

1993-04-01

196

Improving the diagnosis of meningitis due to enterovirus and herpes simplex virus I and II in a tertiary care hospital  

PubMed Central

Background Enterovirus and herpes simplex viruses are common causes of lymphocytic meningitis. The purpose of this study was to analyse the impact of the use molecular testing for Enteroviruses and Herpes simplex viruses I and II in all suspected cases of viral meningitis. Methods From November 18, 2008 to November 17, 2009 (phase II, intervention), all patients admitted with suspected viral meningitis (with pleocytosis) had a CSF sample tested using a nucleic acid amplification test (NAAT). Data collected during this period were compared to those from the previous one-year period, i.e. November 18, 2007 to November 17, 2008 (phase I, observational), when such tests were available but not routinely used. Results In total, 2,536 CSF samples were assessed, of which 1,264 were from phase I, and 1,272 from phase II. Of this total, a NAAT for Enterovirus was ordered in 123 cases during phase I (9.7% of the total phase I sample) and in 221 cases in phase II (17.4% of the total phase II sample). From these, Enterovirus was confirmed in 35 (28.5%, 35/123) patients during phase I and 71 (32.1%, 71/221) patients during phase II (p?=?0.107). The rate of diagnosis of meningitis by HSV I and II did not differ between the groups (13 patients, 6.5% in phase I and 13, 4.7% in phase II) (p?=?1.0), from 200 cases in phase I and 274 cases in phase II. Conclusions The number of cases diagnosed with enteroviral meningitis increased during the course of this study, leading us to believe that the strategy of performing NAAT for Enterovirus on every CSF sample with pleocytosis is fully justified. PMID:24138798

2013-01-01

197

Receptor-Binding Properties of a Soluble Form of Human Cytomegalovirus Glycoprotein B  

Microsoft Academic Search

The human cytomegalovirus (HCMV) glycoprotein B (gB) (also known as gpUL55) homolog is an important mediator of virus entry and cell-to-cell dissemination of infection. To examine the potential ligand-binding properties of gB, a soluble form of gB (gB-S) was radiolabeled, purified, and tested in cell-binding experiments. Binding of gB-S to human fibroblast cells was found to occur in a dose-dependent,

KATHLEEN A. BOYLE; TERESA COMPTON

1998-01-01

198

UNIT 1B.3Phenotypic Analysis of Human Embryonic Stem Cells  

E-print Network

UNIT 1B.3Phenotypic Analysis of Human Embryonic Stem Cells Mark Ungrin,1 Michael O'Connor,2 Columbia ABSTRACT Human embryonic stem cells (hESCs) are an important tool for the study of develop- mental Copyright C 2007 John Wiley & Sons, Inc. Embryonic and Extraembryonic Stem Cells 1B.3.1 Supplement 2 #12

Zandstra, Peter W.

199

A Virus Similar to Human Hepatitis B Virus Associated with Hepatitis and Hepatoma in Woodchucks  

Microsoft Academic Search

Particles with properties similar to those associated with human hepatitis B were found in serum from woodchucks with chronic hepatitis and hepatocellular carcinoma. It is suggested that woodchuck hepatitis virus is a second member of a novel class of viruses represented by the human hepatitis B virus.

Jesse Summers; Jo Marie Smolec; Robert Snyder

1978-01-01

200

The NMDA receptor NR2B subunit contributes to epileptogenesis in human cortical dysplasia  

Microsoft Academic Search

Cortical dysplasia (CD) is often associated with pharmacoresistant epilepsy. Previous studies showed increased expression of the NMDA receptor subunit NR2B in dysplastic and epileptic human neocortex. We tested the hypothesis that differential increase of NR2B constitutes an epileptogenic mechanism in humans. Dysplastic neocortex and lateral temporal lobe regions resected for treatment of pharmacoresistant seizures were processed for electrophysiological, histological, and

Gabriel Möddel; Berit Jacobson; Zhong Ying; Damir Janigro; William Bingaman; Jorge González-Martínez; Christoph Kellinghaus; Richard A. Prayson; Imad M. Najm

2005-01-01

201

Transcriptional and translational mechanisms of cytochrome b5 reductase isoenzyme generation in humans.  

PubMed Central

Cytochrome b5 reductase (b5R) is an essential enzyme that exists in soluble and membrane-bound isoforms, each with specific functions. In the rat, the two forms are generated from alternative transcripts differing in the first exons. In contrast, the biogenesis of b5R isoforms in the human is not yet well understood. In the present study we have detected three novel alternative exons, designated 1S, S' and 1B, located between the first alternative exon 1M and the common second exon in the human b5R gene. Accordingly, multiple M-type, S-type and SS'-type and B-type transcripts are generated. All types of human b5R transcript are expressed ubiquitously. An analysis of in vitro translation products demonstrated an alternative use of different AUG initiators resulting in the production of various human b5R protein isoforms. Our results indicate that the organization of the 5' region of the b5R gene is not conserved between rodents and humans. Insertion of Alu elements into the human b5R gene, in particular just upstream of the S/S' region, could be responsible for dynamic events of gene rearrangement during evolution. PMID:11284742

Leroux, A; Mota Vieira, L; Kahn, A

2001-01-01

202

A Taxonomy of Distributed Human Computation Alexander J. Quinn, Benjamin B. Bederson  

E-print Network

of Maryland Department of Computer Science Human-Computer Interaction Lab College Park, MD 20742 USA {aq human- computer interaction and computer science, educators will require a common vocabulary to teachA Taxonomy of Distributed Human Computation Alexander J. Quinn, Benjamin B. Bederson University

Golbeck, Jennifer

203

1,25-dihydroxyvitamin D{sub 3} impairs NF-{kappa}B activation in human naive B cells  

SciTech Connect

Highlights: {yields} In naive B cells, VDR activation by calcitriol results in reduced NF-{kappa}B p105 and p50 protein expression. {yields} Ligating the VDR with calcitriol causes reduced nuclear translocation of NF-{kappa}B p65. {yields} Reduced nuclear amount of p65 after calcitriol incubation results in reduced binding of p65 on the p105 promoter. {yields} Thus, vitamin D receptor signaling may reduce or prevent activation of B cells and unwanted immune responses, e.g. in IgE dependent diseases such as allergic asthma. -- Abstract: 1{alpha},25-dihydroxyvitamin D{sub 3} (calcitriol), the bioactive metabolite of vitamin D, modulates the activation and inhibits IgE production of anti-CD40 and IL-4 stimulated human peripheral B cells. Engagement of CD40 results in NF-{kappa}B p50 activation, which is essential for the class switch to IgE. Herein, we investigated by which mechanism calcitriol modulates NF-{kappa}B mediated activation of human naive B cells. Naive B cells were predominantly targeted by calcitriol in comparison with memory B cells as shown by pronounced induction of the VDR target gene cyp24a1. Vitamin D receptor activation resulted in a strongly reduced p105/p50 protein and mRNA expression in human naive B cells. This effect is mediated by impaired nuclear translocation of p65 and consequently reduced binding of p65 to its binding site in the p105 promoter. Our data indicate that the vitamin D receptor reduces NF-{kappa}B activation by interference with NF-{kappa}B p65 and p105. Thus, the vitamin D receptor inhibits costimulatory signal transduction in naive B cells, namely by reducing CD40 signaling.

Geldmeyer-Hilt, Kerstin, E-mail: kerstin.hilt@charite.de [Allergie-Centrum-Charite, CCM, Klinik fuer Dermatologie und Allergologie, Charite - Universitaetsmedizin Berlin, Chariteplatz 1, 10117 Berlin (Germany)] [Allergie-Centrum-Charite, CCM, Klinik fuer Dermatologie und Allergologie, Charite - Universitaetsmedizin Berlin, Chariteplatz 1, 10117 Berlin (Germany); Heine, Guido, E-mail: guido.heine@charite.de [Allergie-Centrum-Charite, CCM, Klinik fuer Dermatologie und Allergologie, Charite - Universitaetsmedizin Berlin, Chariteplatz 1, 10117 Berlin (Germany) [Allergie-Centrum-Charite, CCM, Klinik fuer Dermatologie und Allergologie, Charite - Universitaetsmedizin Berlin, Chariteplatz 1, 10117 Berlin (Germany); Deutsches Rheuma-Forschungszentrum Berlin, Chariteplatz 1, 10117 Berlin (Germany); Hartmann, Bjoern, E-mail: bjoern.hartmann@charite.de [Allergie-Centrum-Charite, CCM, Klinik fuer Dermatologie und Allergologie, Charite - Universitaetsmedizin Berlin, Chariteplatz 1, 10117 Berlin (Germany)] [Allergie-Centrum-Charite, CCM, Klinik fuer Dermatologie und Allergologie, Charite - Universitaetsmedizin Berlin, Chariteplatz 1, 10117 Berlin (Germany); Baumgrass, Ria, E-mail: baumgrass@drfz.de [Deutsches Rheuma-Forschungszentrum Berlin, Chariteplatz 1, 10117 Berlin (Germany)] [Deutsches Rheuma-Forschungszentrum Berlin, Chariteplatz 1, 10117 Berlin (Germany); Radbruch, Andreas, E-mail: radbruch@drfz.de [Deutsches Rheuma-Forschungszentrum Berlin, Chariteplatz 1, 10117 Berlin (Germany)] [Deutsches Rheuma-Forschungszentrum Berlin, Chariteplatz 1, 10117 Berlin (Germany); Worm, Margitta, E-mail: margitta.worm@charite.de [Allergie-Centrum-Charite, CCM, Klinik fuer Dermatologie und Allergologie, Charite - Universitaetsmedizin Berlin, Chariteplatz 1, 10117 Berlin (Germany)] [Allergie-Centrum-Charite, CCM, Klinik fuer Dermatologie und Allergologie, Charite - Universitaetsmedizin Berlin, Chariteplatz 1, 10117 Berlin (Germany)

2011-04-22

204

Clinical features and laboratory findings of human parvovirus B19 in human immunodeficiency virus-infected patients  

PubMed Central

Immunocompromised patients may develop severe chronic anaemia when infected by human parvovirus B19 (B19V). However, this is not the case in human immunodeficiency virus (HIV)-infected patients with good adherence to highly active antiretroviral treatment (HAART). In this study, we investigated the clinical evolution of five HIV-infected patients receiving HAART who had B19V infections confirmed by serum polymerase chain reaction. Four of the patients were infected with genotype 1a strains and the remaining patient was infected with a genotype 3b strain. Anaemia was detected in three of the patients, but all patients recovered without requiring immunoglobulin and/or blood transfusions. In all cases, the attending physicians did not suspect the B19V infections. There was no apparent relationship between the infecting genotype and the clinical course. In the HAART era, B19V infections in HIV-positive patients may be limited, subtle or unapparent. PMID:24714965

Pereira, Renata Freire Alves; Garcia, Rita de Cássia Nasser Cubel; de Azevedo, Kátia Martins Lopes; Setúbal, Sérgio; de Siqueira, Marilda Agudo Mendonça Teixeira; de Oliveira, Solange Artimos

2014-01-01

205

Human rhinoviruses.  

PubMed

Human rhinoviruses are the most important causative agents of upper respiratory infections and are also implicated in more severe clinical entities. Although often present, very little is known about human rhinoviruses. Molecular methods have been used in the classification of this large group of viruses into two separate clades. In addition, one known serotype was found to be a member of enterovirus group D. Laboratory diagnosis of human rhinovirus infection is based on reverse transcription polymerase chain reaction methods or the more tedious virus culture but a rapid "bedside" method is unavailable. Anti-rhinoviral therapy has been under extensive study over the past few decades but symptomatic treatment of the common cold is still the only useful approach in clinical use. More data on circulating human rhinovirus strains would facilitate both detection and treatment of these common pathogens. PMID:12758045

Savolainen, Carita; Blomqvist, Soile; Hovi, Tapani

2003-06-01

206

Early B lymphocyte development: Similarities and differences in human and mouse.  

PubMed

B lymphocytes differentiate from hematopoietic stem cells through a series of distinct stages. Early B cell development proceeds in bone marrow until immature B cells migrate out to secondary lymphoid tissues, such as a spleen and lymph nodes, after completion of immunoglobulin heavy and light chain rearrangement. Although the information about the regulation by numerous factors, including signaling molecules, transcription factors, epigenetic changes and the microenvironment, could provide the clinical application, our knowledge on human B lymphopoiesis is limited. However, with great methodological advances, significant progress for understanding B lymphopoiesis both in human and mouse has been made. In this review, we summarize the experimental models for studies about human adult B lymphopoiesis, and the role of microenvironment and signaling molecules, such as cytokines, transforming growth factor-? superfamily, Wnt family and Notch family, with point-by-point comparison between human and mouse. PMID:25258663

Ichii, Michiko; Oritani, Kenji; Kanakura, Yuzuru

2014-09-26

207

Early B lymphocyte development: Similarities and differences in human and mouse  

PubMed Central

B lymphocytes differentiate from hematopoietic stem cells through a series of distinct stages. Early B cell development proceeds in bone marrow until immature B cells migrate out to secondary lymphoid tissues, such as a spleen and lymph nodes, after completion of immunoglobulin heavy and light chain rearrangement. Although the information about the regulation by numerous factors, including signaling molecules, transcription factors, epigenetic changes and the microenvironment, could provide the clinical application, our knowledge on human B lymphopoiesis is limited. However, with great methodological advances, significant progress for understanding B lymphopoiesis both in human and mouse has been made. In this review, we summarize the experimental models for studies about human adult B lymphopoiesis, and the role of microenvironment and signaling molecules, such as cytokines, transforming growth factor-? superfamily, Wnt family and Notch family, with point-by-point comparison between human and mouse. PMID:25258663

Ichii, Michiko; Oritani, Kenji; Kanakura, Yuzuru

2014-01-01

208

Identification of human germinal center light and dark zone cells and their relationship to human B-cell lymphomas  

PubMed Central

Germinal centers (GCs) are sites of B-cell clonal expansion, hypermutation, and selection. GCs are polarized into dark (DZ) and light zones (LZ), a distinction that is of key importance to GC selection. However, the difference between the B cells in each of these zones in humans remains unclear. We show that, as in mice, CXCR4 and CD83 can be used to distinguish human LZ and DZ cells. Using these markers, we show that LZ and DZ cells in mice and humans differ only in the expression of characteristic “activation” and “proliferation” programs, suggesting that these populations represent alternating states of a single-cell type rather than distinct differentiation stages. In addition, LZ/DZ transcriptional profiling shows that, with the exception of “molecular” Burkitt lymphomas, nearly all human B-cell malignancies closely resemble LZ cells, which has important implications for our understanding of the molecular programs of lymphomagenesis. PMID:22740445

Dominguez-Sola, David; Holmes, Antony B.; Deroubaix, Stephanie; Dalla-Favera, Riccardo; Nussenzweig, Michel C.

2012-01-01

209

Human CYP1B1 Is Regulated by Estradiol via Estrogen Receptor  

Microsoft Academic Search

Human cytochrome P450 (CYP) 1B1 is a key enzyme in the metabolism of 17-estradiol (E2). CYP1B1 is mainly expressed in endocrine-regulated tissues, such as mammary, uterus, and ovary. Because many CYP en- zymes are likely to be induced by the substrates themselves, we examined whether the human CYP1B1 expression is regulated by E2 in the present study. Real-time reverse transcription-PCR

Yuki Tsuchiya; Miki Nakajima; Satoru Kyo; Taro Kanaya; Masaki Inoue; Tsuyoshi Yokoi

2004-01-01

210

Human Genome Diversity Project. Summary of planning workshop 3(B): Ethical and human-rights implications  

SciTech Connect

The third planning workshop of the Human Genome Diversity Project was held on the campus of the US National Institutes of Health in Bethesda, Maryland, from February 16 through February 18, 1993. The second day of the workshop was devoted to an exploration of the ethical and human-rights implications of the Project. This open meeting centered on three roundtables, involving 12 invited participants, and the resulting discussions among all those present. Attendees and their affiliations are listed in the attached Appendix A. The discussion was guided by a schedule and list of possible issues, distributed to all present and attached as Appendix B. This is a relatively complete, and thus lengthy, summary of the comments at the meeting. The beginning of the summary sets out as conclusions some issues on which there appeared to be widespread agreement, but those conclusions are not intended to serve as a set of detailed recommendations. The meeting organizer is distributing his recommendations in a separate memorandum; recommendations from others who attended the meeting are welcome and will be distributed by the meeting organizer to the participants and to the Project committee.

NONE

1993-12-31

211

Human articular chondrocytes express functional leukotriene B4 receptors.  

PubMed

Leukotriene B4 (LTB4 ) is a potent chemoattractant associated with the development of osteoarthritis (OA), while its receptors BLT1 and BLT2 have been found in synovium and subchondral bone. In this study, we have investigated whether these receptors are also expressed by human cartilage cells and their potential effects on cartilage cells. The expression of LTB4 receptors in native tissue and cultured cells was assessed by immunohistochemistry, immunocytochemistry, polymerase chain reaction (PCR) and electron microscopy. The functional significance of the LTB4 receptor expression was studied by Western blotting, using phospho-specific antibodies in the presence or absence of receptor antagonists. In further studies, the secretion of pro-inflammatory cytokines, growth factors and metalloproteinases by LTB4 -stimulated chondrocytes was measured by multiplex protein assays. The effects of LTB4 in cartilage signature gene expression in cultured cells were assessed by quantitative PCR, whereas the LTB4 -promoted matrix synthesis was determined using 3D pellet cultures. Both receptors were present in cultured chondrocytes, as was confirmed by immunolabelling and PCR. The relative quantification by PCR demonstrated a higher expression of the receptors in cells from healthy joints compared with OA cases. The stimulation of cultured chondrocytes with LTB4 resulted in a phosphorylation of downstream transcription factor Erk 1/2, which was reduced after blocking BLT1 signalling. No alteration in the secretion of cytokine and metalloproteinases was recorded after challenging cultured cells with LTB4 ; likewise, cartilage matrix gene expression and 3D tissue synthesis were unaffected. Chondrocytes express BLT1 and BLT2 receptors, and LTB4 activates the downstream Erk 1/2 pathway by engaging the high-affinity receptor BLT1. However, any putative role in cartilage biology could not be revealed, and remains to be clarified. PMID:25677035

Hansen, Ann Kristin; Indrevik, Jill-Tove; Figenschau, Yngve; Martinez-Zubiaurre, Inigo; Sveinbjörnsson, Baldur

2015-03-01

212

EphB and Ephrin-B interactions mediate human mesenchymal stem cell suppression of activated T-cells.  

PubMed

Mesenchymal stromal/stem cells (MSC) express the contact-dependent erythropoietin-producing hepatocellular (Eph) receptor tyrosine kinase family and their cognate ephrin ligands, which are known to regulate thymocyte maturation and selection, T-cell transendothelial migration, activation, co-stimulation, and proliferation. However, the contribution of Eph/ephrin molecules in mediating human MSC suppression of activated T-cells remains to be determined. In the present study, we showed that EphB2 and ephrin-B2 are expressed by ex vivo expanded MSC, while the corresponding ligands, ephrin-B1 and EphB4, respectively, are highly expressed by T-cells. Initial studies demonstrated that EphB2-Fc and ephrin-B2-Fc molecules suppressed T-cell proliferation in allogeneic mixed lymphocyte reaction (MLR) assays compared with human IgG-treated controls. While the addition of a third-party MSC population demonstrated dramatic suppression of T-cell proliferation responses in the MLR, blocking the function of EphB2 or EphB4 receptors using inhibitor binding peptides significantly increased T-cell proliferation. Consistent with these observations, shRNA EphB2 or ephrin-B2 knockdown expression in MSC reduced their ability to inhibit T-cell proliferation. Importantly, the expression of immunosuppressive factors, indoleamine 2, 3-dioxygenase, transforming growth factor-?1, and inducible nitric oxide synthase expressed by MSC, was up-regulated after stimulation with EphB4 and ephrin-B1 in the presence of interferon (IFN)-?, compared with untreated controls. Conversely, key factors involved in T-cell activation and proliferation, such as interleukin (IL)-2, IFN-?, tumor necrosis factor-?, and IL-17, were down-regulated by T-cells treated with EphB2 or ephrin-B2 compared with untreated controls. Studies utilizing signaling inhibitors revealed that inhibition of T-cell proliferation is partly mediated through EphB2-induced ephrin-B1 reverse signaling or ephrin-B2-mediated EphB4 forward signaling by activating Src, PI3Kinase, Abl, and JNK kinase pathways, activated by tyrosine phosphorylation. Taken together, these observations suggest that EphB/ephrin-B interactions play an important role in mediating human MSC inhibition of activated T cells. PMID:23711177

Nguyen, Thao M; Arthur, Agnes; Hayball, John D; Gronthos, Stan

2013-10-15

213

In vivo time-related evaluation of a therapeutic neutralization monoclonal antibody against lethal enterovirus 71 infection in a mouse model.  

PubMed

Enterovirus 71 (EV71) is a neurotropic virus capable of inducing severe neurological symptoms and death. No direct targeting antivirals are useful in the treatment of severe EV71 infection. Because of low toxicity and good specificity, monoclonal antibodies (MAb) are a potential candidate for the treatment of viral infections. Therefore, we developed an EV71-specific conformational MAb with high in vitro cross-neutralization activity to heterologous EV71 subgenotypes. The in vivo treatment experiment at different days post-infection indicated that a single treatment of MAb CT11F9 within day 3 post-infection fully protected mice from morbidity and mortality (0% PBS vs. 100% at 10 µg/g per body weight ***P<0.0001). Immunohistochemical and histological analysis confirmed that CT11F9 significantly prohibited EV71 VP1 expression in various tissues and prevented EV71-induced myonecrosis. Moreover, thrice-treatment at day 4, 5, 6 post-infection was associated with an increased survival rate (18.2% single vs. 50% thrice at 20 µg/g per body weight), and the mice recovered from limb paralysis. Competitive ELISA also confirmed that CT11F9-recognized epitopes were immunodominant in humans. In conclusion, MAb CT11F9 is an ideal candidate to be humanized and used in severe EV71 infection. PMID:25279734

Li, Zhiqun; Xu, Longfa; He, Delei; Yang, Lisheng; Liu, Che; Chen, Yixin; Shih, James Wai Kuo; Zhang, Jun; Zhao, Qinjian; Cheng, Tong; Xia, Ningshao

2014-01-01

214

Human vitamin B12 absorption measurement by accelerator mass spectrometry using specifically  

E-print Network

Human vitamin B12 absorption measurement by accelerator mass spectrometry using specifically to assimilate dietary vitamin B12. Assaying and understanding absorption and uptake of B12 is important because and showed plasma appearance and clearance curves consistent with the predicted behavior of the pure vitamin

California at Davis, University of

215

Efficacy of IFN-?1 to Protect Human Airway Epithelial Cells against Human Rhinovirus 1B Infection  

PubMed Central

Impaired interferon (IFN) production has been observed in various obstructive respiratory diseases. This contributes to enhanced sensitivity towards viral infections triggering acute exacerbations. To compensate for this impaired host IFN response, there is need to explore new therapeutic strategies, like exogenous administration of IFNs as prophylactic treatment. In the present study, we examined the protective potential of IFN-?1 and compared it with the previously established protecting effect of IFN-?. A549 cells and human primary bronchial epithelial cells were first treated with either IFN-? (500 IU/ml) or IFN-?1 (500 ng/ml) for 18 h. For infection, two approaches were adopted: i) Continuous scenario: after pre-treatment, cells were infected immediately for 24 h with human rhinovirus 1B (HRV1B) in IFN-containing medium, or were cultured for another 72 h in IFN-containing medium, and then infected for 24 h with HRV1B, ii) Pre-treatment scenario: IFN-containing medium was replaced after 18 h and cells were infected for 4 h either immediately after pre-treatment or after additional culturing for 72 h in IFN-free medium. The protective effect was evaluated in terms of reduction in the number of viral copies/infectious progeny, and enhanced expression of IFN-stimulated genes (ISGs). In both cell types and in both approaches, IFN-?1 and IFN-? treatment resulted in pronounced and long-lasting antiviral effects exemplified by significantly reduced viral copy numbers and diminished infectious progeny. This was associated with strong up-regulation of multiple ISGs. However, in contrast to the IFN-? induced expression of ISGs, which decreased over time, expression of ISGs induced by IFN-?1 was sustained or even increased over time. Here we demonstrate that the protective potential of IFN-?1 is comparable to IFN-?. Yet, the long-lasting induction of ISGs by IFN-?1 and most likely less incitement of side effects due to more localized expression of its receptors could make it an even more promising candidate for prophylactic treatment than IFN-?. PMID:24751942

Gulraiz, Fahad; Bellinghausen, Carla; Dentener, Mieke A.; Reynaert, Niki L.; Gaajetaan, Giel R.; Beuken, Erik V.; Rohde, Gernot G.; Bruggeman, Cathrien A.; Stassen, Frank R.

2014-01-01

216

Viral infection of engrafted human islets leads to diabetes.  

PubMed

Type 1 diabetes (T1D) is characterized by the destruction of the insulin-producing ?-cells of pancreatic islets. Genetic and environmental factors both contribute to T1D development. Viral infection with enteroviruses is a suspected trigger for T1D but a causal role remains unproven and controversial. Studies in animals are problematic because of species-specific differences in host cell susceptibility and immune responses to candidate viral pathogens such as coxsackie B virus (CVB). In order to resolve the controversial role of viruses in human T1D, we developed a viral infection model in immunodeficient mice bearing human islet grafts. Hyperglycemia was induced in mice by specific ablation of native ?-cells. Human islets, which are naturally susceptible to CVB infection, were transplanted to restore normoglycemia. Transplanted mice were infected with CVB4 and monitored for hyperglycemia. Forty-seven percent of CVB4-infected mice developed hyperglycemia. Human islet grafts from infected mice contained viral RNA, expressed viral protein, and had reduced insulin compared to grafts from uninfected mice. Human-specific gene expression profiles in grafts from infected mice revealed the induction of multiple interferon stimulated genes. Thus, human islets can become severely dysfunctional with diminished insulin production following CVB infection of ?-cells, resulting in diabetes. PMID:25392246

Gallagher, Glen R; Brehm, Michael A; Finberg, Robert W; Barton, Bruce A; Shultz, Leonard D; Greiner, Dale L; Bortell, Rita; Wang, Jennifer P

2014-11-12

217

Centromere protein B assembles human centromeric alpha-satellite DNA at the 17-bp sequence, CENP-B box  

PubMed Central

We purified 15,000-fold from HeLa cell nuclear extract the centromere antigen that reacts specifically with the 17-bp sequence, designated previously as CENP-B box, in human centromeric alpha-satellite (alphoid) DNA by a two-step procedure including an oligonucleotide affinity column. The purified protein was identified as the centromere protein B (CENP-B) by its mobility on SDS-PAGE (80 kD), and reactivities to a monoclonal antibody raised to CENP-B (bacterial fusion protein) and to anticentromere sera from patients with autoimmune diseases. Direct binding by CENP-B of the CENP-B box sequence in the alphoid DNA has been proved using the purified CENP-B by DNA mobility-shift assay, Southwestern blotting, and DNase I protection analysis. The binding constant of the antigen to the CENP-B box sequence is 6 x 10(8) M-1. DNA mobility-shift assays indicated that the major complex formed between the CENP-B and the DNA contains two DNA molecules, suggesting the importance of the CENP-B/CENP-B box interaction in organization of higher ordered chromatin structures in the centromere and/or kinetochore. Location of DNA binding and dimerization domains in CENP-B was discussed based on the DNA mobility- shift assays performed with a protein fraction containing intact and partial cleavage products of CENP-B. PMID:1730770

1992-01-01

218

Sulfotransferase 2B1b in Human Breast: Differences in Subcellular Localization in African American and Caucasian Women  

PubMed Central

Breast cancer (BC) is the most commonly diagnosed cancer among American women; however, the development of postmenopausal BC is significantly lower in African Americans as compared to Caucasians. Hormonal stimulation is important in BC development and differences in the conversion of dehydroepiandrosterone (DHEA) into estrogens may be involved in the lower incidence of post-menopausal BC in African American women. DHEA sulfation by SULT2B1b is important in regulating the conversion of DHEA into estrogens in tissues. SULT2B1b is localized in both cytosol and nuclei of some tissues including cancerous and associated-normal breast tissue. Immunohistochemical staining was used to evaluate the total expression and subcellular localization of SULT2B1b in African American and Caucasian breast tissues. Cell fractionation, immunoblot analysis and sulfation assays were used to characterize the subcellular expression and activity of SULT2B1b in BC tissues and T-47D breast adenocarcinoma cells. Immunohistochemical analysis of SULT2B1b showed that African Americans had a significantly greater amount of SULT2B1b in epithelial cells of associated-normal breast tissue as compared to Caucasians. Also, more SULT2B1b in African American associated-normal breast epithelial cells was localized in the nuclei than in Caucasians. Equivalent levels of SULT2B1b were detected in breast adenocarcinoma tissues from both African American and Caucasian women. Nuclei isolation and immunoblot analysis of both BC tissue and human T-47D breast adenocarcinoma cells demonstrated that SULT2B1b is present in nuclei and cytoplasm. PMID:18586095

Dumas, Nicole A; He, Dongning; Frost, Andra R; Falany, Charles N

2008-01-01

219

Gene-Specific Repression of Proinflammatory Cytokines in Stimulated Human Macrophages by Nuclear I?B?  

PubMed Central

We have previously shown that increased nuclear accumulation of I?B? inhibits NF-?B activity and induces apoptosis in human leukocytes. In this study, we wanted to explore the possibility that the nucleocytoplasmic distribution of I?B? can be used as a therapeutic target for the regulation of NF-?B–dependent cytokine synthesis. Treatment of LPS-stimulated human U937 macrophages with an inhibitor of chromosome region maintenance 1-dependent nuclear export, leptomycin B, resulted in the increased nuclear accumulation of I?B? and inhibition of NF-?B DNA binding activity, caused by the nuclear I?B?-p65 NF-?B interaction. Surprisingly, however, whereas mRNA expression and cellular release of TNF-?, the ? form of pro-IL-1 (IL-1?), and IL-6 were inhibited by the leptomycin B-induced nuclear I?B?, IL-8 mRNA expression and cellular release were not significantly affected. Analysis of in vivo recruitment of p65 NF-?B to NF-?B–regulated promoters by chromatin immunoprecipitation in U937 cells and human PBMCs indicated that although the p65 recruitment to TNF-?, IL-1?, and IL-6 promoters was inhibited by the nuclear I?B?, p65 recruitment to IL-8 promoter was not repressed. Chromatin immunoprecipitation analyses using I?B? and S536 phosphospecific p65 NF-?B Abs demonstrated that although the newly synthesized I?B? induced by postinduction repression is recruited to TNF-?, IL-1?, and IL-6 promoters but not to the IL-8 promoter, S536-phosphorylated p65 is recruited to IL-8 promoter, but not to TNF-?, IL-1?, or IL-6 promoters. Together, these data indicate that the inhibition of NF-?B–dependent transcription by nuclear I?B? in LPS-stimulated macrophages is gene specific and depends on the S536 phosphorylation status of the recruited p65 NF-?B. PMID:20696864

Ghosh, Chandra C.; Ramaswami, Sitharam; Juvekar, Ashish; Vu, Hai-Yen; Galdieri, Luciano; Davidson, Dennis; Vancurova, Ivana

2011-01-01

220

The Enterovirus 71 procapsid binds neutralizing antibodies and rescues virus infection in vitro.  

PubMed

Enterovirus 71 (EV71) is responsible for seasonal outbreaks of hand, foot, and mouth disease in the Asia-Pacific region. The virus has the capability of causing severe disease and death, especially in young children. Although several vaccines are currently in clinical trials no vaccines or therapeutics have been approved for use. Previous structural studies have revealed that two antigenically distinct capsid forms are produced in EV71 infected cells: an expanded empty capsid, sometimes called procapsid, and the infectious virus. Specifically an immunodominant epitope of EV71 that maps to the virus canyon is structurally different between the procapsid and virus. This structure function study shows that the procapsid can sequester antibodies thus enhancing EV71 infection in vitro. The results presented here suggest that due to conformational differences between the EV71 procapsid and virus, the presence of the procapsid in natural virus infections should be considered in the future design of vaccines or therapeutics. PMID:25428877

Shingler, Kristin L; Cifuente, Javier O; Ashley, Robert E; Makhov, Alexander M; Conway, James F; Hafenstein, Susan

2014-11-26

221

Enterovirus 71 infection cleaves a negative regulator for viral internal ribosomal entry site-driven translation.  

PubMed

Far-upstream element-binding protein 2 (FBP2) is an internal ribosomal entry site (IRES) trans-acting factor (ITAF) that negatively regulates enterovirus 71 (EV71) translation. This study shows that EV71 infection cleaved FBP2. Live EV71 and the EV71 replicon (but not UV-inactivated virus particles) induced FBP2 cleavage, suggesting that viral replication results in FBP2 cleavage. The results also showed that virus-induced proteasome, autophagy, and caspase activity co-contribute to EV71-induced FBP2 cleavage. Using FLAG-fused FBP2, we mapped the potential cleavage fragments of FBP2 in infected cells. We also found that FBP2 altered its function when its carboxyl terminus was cleaved. This study presents a mechanism for virus-induced cellular events to cleave a negative regulator for viral IRES-driven translation. PMID:23345520

Chen, Li-Lien; Kung, Yu-An; Weng, Kuo-Feng; Lin, Jing-Yi; Horng, Jim-Tong; Shih, Shin-Ru

2013-04-01

222

Inhibition of enterovirus 71 infection by antisense octaguanidinium dendrimer-conjugated morpholino oligomers.  

PubMed

Enterovirus 71 (EV-71) infections are generally manifested as mild hand, foot and mouth disease, but have been reported to cause severe neurological complications with high mortality rates. Treatment options remain limited due to the lack of antivirals. Octaguanidinium-conjugated morpholino oligomers (vivo-MOs) are single-stranded DNA-like antisense agents that can readily penetrate cells and reduce gene expression by steric blocking of complementary RNA sequences. In this study, inhibitory effects of three vivo-MOs that are complementary to the EV-71 internal ribosome entry site (IRES) and the RNA-dependent RNA polymerase (RdRP) were tested in RD cells. Vivo-MO-1 and vivo-MO-2 targeting the EV-71 IRES showed significant viral plaque reductions of 2.5 and 3.5 log10PFU/ml, respectively. Both vivo-MOs reduced viral RNA copies and viral capsid expression in RD cells in a dose-dependent manner. In contrast, vivo-MO-3 targeting the EV-71 RdRP exhibited less antiviral activity. Both vivo-MO-1 and 2 remained active when administered either 4h before or within 6h after EV-71 infection. Vivo-MO-2 exhibited antiviral activities against poliovirus (PV) and coxsackievirus A16 but vivo-MO-1 showed no antiviral activities against PV. Both the IRES-targeting vivo-MO-1 and vivo-MO-2 inhibit EV-71 RNA translation. Resistant mutants arose after serial passages in the presence of vivo-MO-1, but none were isolated against vivo-MO-2. A single T to C substitution at nucleotide position 533 was sufficient to confer resistance to vivo-MO-1. Our findings suggest that IRES-targeting vivo-MOs are good antiviral candidates for treating early EV-71 infection, and vivo-MO-2 is a more favorable candidate with broader antiviral spectrum against enteroviruses and are refractory to antiviral resistance. PMID:24769243

Tan, Chee Wah; Chan, Yoke Fun; Quah, Yi Wan; Poh, Chit Laa

2014-07-01

223

Development and Evaluation of EPA Method 1615 for Detection of Enterovirus and Norovirus in Water  

PubMed Central

The U.S. EPA developed a sample concentration and preparation assay in conjunction with the total culturable virus assay for concentrating and measuring culturable viruses in source and drinking waters as part of the Information Collection Rule (ICR) promulgated in 1996. In an effort to improve upon this method, the U.S. EPA recently developed Method 1615: Measurement of Enterovirus and Norovirus Occurrence in Water by Culture and RT-qPCR. Method 1615 uses a culturable virus assay with reduced equipment and labor costs compared to the costs associated with the ICR virus method and introduces a new molecular assay for the detection of enteroviruses and noroviruses by reverse transcription-quantitative PCR. In this study, we describe the optimization of several new components of the molecular assay and examine virus recovery from ground, reagent-grade, and surface water samples seeded with poliovirus type 3 and murine norovirus. For the culturable virus and molecular assays, mean poliovirus recovery using the complete method was 58% and 20% in groundwater samples, 122% and 39% using low-titer spikes in reagent-grade water, 42% and 48% using high-titer spikes in reagent-grade water, and 11% and 10% in surface water with high turbidity, respectively. Murine norovirus recovery by the molecular assay was 30% in groundwater samples, less than 8% in both low- and high-titer spikes in reagent-grade water, and 6% in surface water with high turbidity. This study demonstrates the effectiveness of Method 1615 for use with groundwater samples and highlights the need for further research into its effectiveness with surface water. PMID:23087037

Brinkman, Nichole E.; Griffin, Shannon M.; McMinn, Brian R.; Rhodes, Eric R.; Varughese, Eunice A.; Grimm, Ann C.; Parshionikar, Sandhya U.; Wymer, Larry; Fout, G. Shay

2013-01-01

224

Enhanced skin carcinogenesis and lack of thymus hyperplasia in transgenic mice expressing human cyclin D1b (CCND1b)  

PubMed Central

Cyclin D1b is an alternative transcript of the cyclin D1 gene (CCND1) expressed in human tumors. Its abundance is regulated by a single base pair polymorphism at the exon 4/intron 4 boundary (nucleotide 870). Epidemiological studies have shown a correlation between the presence of the G870A allele (that favors the splicing for cyclin D1b) with increased risk and less favorable outcome in several forms of cancer. More recently, it has been shown that, unlike cyclin D1a, the alternative transcript D1b by itself has the capacity to transform fibroblasts in vitro. In order to study the oncogenic potential of cyclin D1b, we developed transgenic mice expressing human cyclin D1b under the control of the bovine K5 promoter (K5D1b mice). Seven founders were obtained and none of them presented any significant phenotype or developed spontaneous tumors. Interestingly, K5D1b mice do not develop the fatal thymic hyperplasia, which is characteristic of the cyclin D1a transgenic mice (K5D1a). Susceptibility to skin carcinogenesis was tested in K5D1b mice using two-stage carcinogenesis protocols. In two independent experiments, K5D1b mice developed higher papilloma multiplicity as compared with wild-type littermates. However, when K5D1b mice were crossed with cyclin D1KO mice, the expression of cyclin D1b was unable to rescue the carcinogenesis-resistant phenotype of the cyclin D1 KO mice. To further explore the role of cyclin D1b in mouse models of carcinogenesis we carried out in silico analysis and in vitro experiments to evaluate the existence of a mouse homologous of the human cyclin D1b transcript. We were unable to find any evidence of an alternatively spliced transcript in mouse Ccnd1. These results show that human cyclin D1b has different biological functions than cyclin D1a and confirm its oncogenic properties. PMID:18942117

Rojas, Paola; Benavides, Fernando; Blando, Jorge; Perez, Carlos; Cardenas, Kim; Richie, Ellen; Knudsen, Erik S.; Johnson, David G.; Senderowicz, Adrian M.; Rodriguez-Puebla, Marcelo L.; Conti, Claudio J.

2009-01-01

225

An RNA replication-center assay for high content image-based quantifications of human rhinovirus and coxsackievirus infections  

Microsoft Academic Search

BACKGROUND: Picornaviruses are common human and animal pathogens, including polio and rhinoviruses of the enterovirus family, and hepatits A or food-and-mouth disease viruses. There are no effective countermeasures against the vast majority of picornaviruses, with the exception of polio and hepatitis A vaccines. Human rhinoviruses (HRV) are the most prevalent picornaviruses comprising more than one hundred serotypes. The existing and

Andreas Jurgeit; Stefan Moese; Pascal Roulin; Alexander Dorsch; Mark Lötzerich; Wai-Ming Lee; Urs F Greber

2010-01-01

226

B7-h2 is a costimulatory ligand for CD28 in human.  

PubMed

CD28 and CTLA-4 are cell surface cosignaling molecules essential for the control of T cell activation upon the engagement of their ligands B7-1 and B7-2 from antigen-presenting cells. By employing a receptor array assay, we have demonstrated that B7-H2, best known as the ligand of inducible costimulator, was a ligand for CD28 and CTLA-4 in human, whereas these interactions were not conserved in mouse. B7-H2 and B7-1 or B7-2 interacted with CD28 through distinctive domains. B7-H2-CD28 interaction was essential for the costimulation of human T cells' primary responses to allogeneic antigens and memory recall responses. Similar to B7-1 and B7-2, B7-H2 costimulation via CD28 induced survival factor Bcl-xL, downregulated cell cycle inhibitor p27(kip1), and triggered signaling cascade of ERK and AKT kinase-dependent pathways. Our findings warrant re-evaluation of CD28 and CTLA-4's functions previously attributed exclusively to B7-1 and B7-2 and have important implications in therapeutic interventions against human diseases. PMID:21530327

Yao, Sheng; Zhu, Yuwen; Zhu, Gefeng; Augustine, Mathew; Zheng, Linghua; Goode, Diana J; Broadwater, Megan; Ruff, William; Flies, Sarah; Xu, Haiying; Flies, Dallas; Luo, Liqun; Wang, Shengdian; Chen, Lieping

2011-05-27

227

Inferring nonneutral evolution from contrasting patterns of polymorphisms and divergences in different protein coding regions of enterovirus 71 circulating in Taiwan during 1998-2003  

PubMed Central

Background Enterovirus (EV) 71 is one of the common causative agents for hand, foot, and, mouth disease (HFMD). In recent years, the virus caused several outbreaks with high numbers of deaths and severe neurological complications. Despite the importance of these epidemics, several aspects of the evolutionary and epidemiological dynamics, including viral nucleotide variations within and between different outbreaks, rates of change in immune-related structural regions vs. non-structural regions, and forces driving the evolution of EV71, are still not clear. Results We sequenced four genomic segments, i.e., the 5' untranslated region (UTR), VP1, 2A, and 3C, of 395 EV71 viral strains collected from 1998 to 2003 in Taiwan. The phylogenies derived from different genomic segments revealed different relationships, indicating frequent sequence recombinations as previously noted. In addition to simple recombinations, exchanges of the P1 domain between different species/genotypes of human enterovirus species (HEV)-A were repeatedly observed. Contrasting patterns of polymorphisms and divergences were found between structural (VP1) and non-structural segments (2A and 3C), i.e., the former was less polymorphic within an outbreak but more divergent between different HEV-A species than the latter two. Our computer simulation demonstrated a significant excess of amino acid replacements in the VP1 region implying its possible role in adaptive evolution. Between different epidemic seasons, we observed high viral diversity in the epidemic peaks followed by severe reductions in diversity. Viruses sampled in successive epidemic seasons were not sister to each other, indicating that the annual outbreaks of EV71 were due to genetically distinct lineages. Conclusions Based on observations of accelerated amino acid changes and frequent exchanges of the P1 domain, we propose that positive selection and subsequent frequent domain shuffling are two important mechanisms for generating new genotypes of HEV-A. Our viral dynamics analysis suggested that the importation of EV71 from surrounding areas likely contributes to local EV71 outbreaks. PMID:20868512

2010-01-01

228

Human blood IgM "memory" B cells are circulating splenic marginal zone B cells harboring a prediversified immunoglobulin repertoire  

PubMed Central

The human peripheral B cell compartment displays a large population of IgM+IgD+CD27+ “memory” B cell carrying a mutated Ig receptor. We show here, by phenotypic analysis, CDR3 spectratyping during a T-independent response and gene expression profiling of the different blood and splenic B cell subsets, that blood IgM+IgD+CD27+ cells correspond to circulating splenic marginal zone B cells. Furthermore, analysis of this peripheral subset in normal children below 2 years shows that these B cells develop and mutate their Ig receptor during ontogeny, prior to their differentiation into T-independent antigen-responsive cells. It is therefore proposed that these IgM+IgD+CD27+ B cells provide the splenic marginal zone with a diversified and protective pre-immune repertoire in charge of the responses against encapsulated bacteria. PMID:15191950

Weller, Sandra; Braun, Moritz C.; Tan, Bruce K.; Rosenwald, Andreas; Cordier, Corinne; Conley, Mary Ellen; Plebani, Alessandro; Kumararatne, Dinakhanta S.; Bonnet, Damien; Tournilhac, Olivier; Tchernia, Gil; Steiniger, Birte; Staudt, Louis M.; Casanova, Jean-Laurent; Reynaud, Claude-Agnès; Weill, Jean-Claude

2004-01-01

229

Continuous myocloni and tonic spasms in a 2-month-old infant with enterovirus 71 brain stem encephalitis.  

PubMed

Brain stem encephalitis is a cardinal presentation of central nervous system involvement in enterovirus 71 infection, and manifests as myoclonus, ataxia, tremor, and autonomic dysfunction. A 2-month-old infant with enterovirus 71 brain stem encephalitis demonstrated continuous myocloni and tonic spasms. On admission, the patient's myoclonus, which mainly involved the shoulders and the arms, was considerably worse during wakefulness and occurred once or twice a minute. Several hours after admission, the myoclonic jerks steadily worsened, appeared ceaselessly every 1 to 2?seconds, and were intermixed with tonic spasms of all four extremities accompanied by crying. Video electroencephalography revealed a normal background without epileptiform discharges and no ictal electroencephalographic changes during the myoclonic jerks and tonic spasms. Complete remission was achieved without complications after completion of a 3-day immunoglobulin therapy. This case suggests that the brain stem may be a major origin site for not only myoclonus but also tonic spasm. PMID:25290724

Lee, Kyung Yeon; Yeh, Hye-Ryun

2015-02-01

230

Identification of detergents as components of wastewater sludge that modify the thermal stability of reovirus and enteroviruses.  

PubMed Central

The agent in wastewater sludge previously shown to reduce the heat required to inactivate reovirus (R. L. Ward and C. S. Ashley, Appl. Environ. Microbiol. 34:681--688, 1977) was "separated" from other sludge components and analyzed by infrared spectroscopy. The infrared spectrum of this material was quite similar to the spectra of commercial anionic detergents, and subsequent analyses of the fractionated sludge samples revealed that anionic detergents in sludge were copurified with the virucidal activity. Further measurements on the virucidal activities of specific detergents revealed that ionic detergents reduce the heat required to inactivate reovirus, that cationic detergents are more active than anionic, and that nonionic detergents are inactive. Several detergents were also shown to protect poliovirus and other enteroviruses against inactivation by heat. These results indicate that ionic detergents are the major component in wastewater sludge that reduce the thermal stability of reovirus and, in addition, that detergents are able to protect enteroviruses against heat. PMID:216308

Ward, R L; Ashley, C S

1978-01-01

231

Dynamic Control of Human Eye on Head System Bijoy K. Ghosh1, Indika B. Wijayasinghe1  

E-print Network

Dynamic Control of Human Eye on Head System Bijoy K. Ghosh1, Indika B. Wijayasinghe1 1. Laboratory for BioCybernetics and Intelligent Systems, Texas Tech University, Lubbock, Texas, USA E-mail: {bijoy.ghosh

Ghosh, Bijoy K.

232

B7-H5 costimulates human T cells via CD28H  

E-print Network

The B7/CD28 family has profound modulatory effects in immune responses and constitutes an important target for the development of novel therapeutic drugs against human diseases. Here we describe a new CD28 homologue (CD28H) ...

Zhu, Yuwen

233

Human Immunoglobulin Heavy Chain Genes Map to a Region of Translocations in Malignant B Lymphocytes  

Microsoft Academic Search

A human immunoglobulin heavy chain (gamma 4) gene is mapped by chromosome hybridization in situ. This gene is located at band 14q32, a site commonly involved in a chromosomal translocation characteristic of malignant B cells.

Ilan R. Kirsch; Cynthia C. Morton; Kenneth Nakahara; Philip Leder

1982-01-01

234

Seven Strains of Enterovirus D68 Detected in the United States during the 2014 Severe Respiratory Disease Outbreak  

PubMed Central

Clusters of severe respiratory disease in the United States were reported to the CDC beginning in August 2014. Enterovirus D68 (EV-D68) was identified from 83% (30/36) of initial severe cases. Investigations in August and September found severe EV-D68 cases to be widespread across the United States. We report seven EV-D68 genomes from the outbreak. PMID:25414503

Brown, B. A.; Nix, W. A.; Sheth, M.; Frace, M.

2014-01-01

235

Harnessing Gene Conversion in Chicken B Cells to Create a Human Antibody Sequence Repertoire  

PubMed Central

Transgenic chickens expressing human sequence antibodies would be a powerful tool to access human targets and epitopes that have been intractable in mammalian hosts because of tolerance to conserved proteins. To foster the development of the chicken platform, it is beneficial to validate transgene constructs using a rapid, cell culture-based method prior to generating fully transgenic birds. We describe a method for the expression of human immunoglobulin variable regions in the chicken DT40 B cell line and the further diversification of these genes by gene conversion. Chicken VL and VH loci were knocked out in DT40 cells and replaced with human VK and VH genes. To achieve gene conversion of human genes in chicken B cells, synthetic human pseudogene arrays were inserted upstream of the functional human VK and VH regions. Proper expression of chimeric IgM comprised of human variable regions and chicken constant regions is shown. Most importantly, sequencing of DT40 genetic variants confirmed that the human pseudogene arrays contributed to the generation of diversity through gene conversion at both the Igl and Igh loci. These data show that engineered pseudogene arrays produce a diverse pool of human antibody sequences in chicken B cells, and suggest that these constructs will express a functional repertoire of chimeric antibodies in transgenic chickens. PMID:24278246

Schusser, Benjamin; Yi, Henry; Collarini, Ellen J.; Izquierdo, Shelley Mettler; Harriman, William D.; Etches, Robert J.; Leighton, Philip A.

2013-01-01

236

Comparison of human B cell activation by TLR7 and TLR9 agonists  

Microsoft Academic Search

BACKGROUND: Human B cells and plasmacytoid dendritic cells (pDC) are the only cells known to express both TLR7 and TLR9. Plasmacytoid dendritic cells are the primary IFN-? producing cells in response to TLR7 and TLR9 agonists. The direct effects of TLR7 stimulation on human B cells is less understood. The objective of this study was to compare the effects of

John A Hanten; John P Vasilakos; Christie L Riter; Lori Neys; Kenneth E Lipson; Sefik S Alkan; Woubalem Birmachu

2008-01-01

237

Coxsackievirus A 16 infection does not interfere with the specific immune response induced by an enterovirus 71 inactivated vaccine in rhesus monkeys.  

PubMed

Hand, foot and mouth disease is usually caused by enterovirus 71 (EV71) and coxsackievirus A 16 (CA16), which are members of the Picornaviridae family. In the present study, the characteristics of the immune response induced by an EV71 inactivated vaccine (made from human diploid cells) were explored in the presence of CA16 infection, based on the previously established neonatal rhesus monkey model. The typical clinical manifestations, including body temperature, viral viremia and virus shedding in the mouth, pharynx and feces, were characterized. A specific neutralizing antibody assay showed that the specific immune response induced by the EV71 inactivated vaccine was active against EV71 but not against CA16. No remarkable fluctuation in proinflammatory cytokine release was identified in the serum of immunized monkeys with EV71 vaccine and CA16 infections subsequently. The results showed that the specific immune response induced by the EV71 inactivated vaccine is effective against EV71 infection but is not affected by CA16 infection. PMID:24958699

Wang, Jingjing; Qi, Sudong; Zhang, Xiaolong; Zhang, Ying; Liu, Longding; Che, Yanchun; He, Zhanlong; Zhao, Yuan; Lu, Shuaiyao; Yu, Wenhai; Li, Qihan

2014-07-31

238

Enterovirus genomes in wastewater: concentration on glass wool and glass powder and detection by RT-PCR.  

PubMed

Standard methods for detecting enteroviruses in environmental samples require cell culture, which is time consuming and expensive. The reverse transcription-polymerase chain reaction (RT-PCR) is a rapid, sensitive method for detecting enteroviruses in water. However, environmental samples often contain substances that inhibit PCR amplification of target RNA. Hence the virus must be concentrated by procedures that do not interfere with amplification. This study shows that virus concentration by adsorption onto glass powder or glass wool supports is suitable for detecting viral genomes in treated wastewater by RT semi-nested PCR. No enterovirus genome was detected directly in 25 samples of treated wastewater by RT semi-nested PCR. However, samples concentrated by adsorption onto glass wool or glass powder showed that 48% (glass powder) and 56% (glass wool) contained virus. Secondary concentration by organic flocculation was unsuitable for detecting virus concentrated on glass wool (20% positive samples), but it helped to increase the detection of the genome after concentration on glass powder (72% positive samples). PMID:9186950

Gantzer, C; Senouci, S; Maul, A; Levi, Y; Schwartzbrod, L

1997-05-01

239

A feeder-free differentiation system identifies autonomously proliferating B cell precursors in human bone marrow.  

PubMed

The peripheral B cell compartment is maintained by homeostatic proliferation and through replenishment by bone marrow precursors. Because hematopoietic stem cells cycle at a slow rate, replenishment must involve replication of precursor B cells. To study proliferation of early human B cell progenitors, we established a feeder cell-free in vitro system allowing the development of B cells from CD34(+) hematopoietic stem cells up to the stage of immature IgM(+) B cells. We found that pro-B and pre-B cells generated in vitro can proliferate autonomously and persist up to 7 wk in culture in the absence of signals induced by exogenously added cytokines. Nevertheless, addition of IL-7 enhanced pre-B cell expansion and inhibited maturation into IgM(+) B cells. The B cell precursor subsets replicating in vitro were highly similar to the bone marrow B cell precursors cycling in vivo. The autonomous proliferation of B cell precursor subsets in vitro and their long-term persistence implies that proliferation during pro-B and pre-B cell stages plays an important role in the homeostasis of the peripheral B cell compartment. Our in vitro culture can be used to study defects in B cell development or in reconstitution of the B cell pool after depletion and chemotherapy. PMID:24379121

Kraus, Helene; Kaiser, Sandra; Aumann, Konrad; Bönelt, Peter; Salzer, Ulrich; Vestweber, Dietmar; Erlacher, Miriam; Kunze, Mirjam; Burger, Meike; Pieper, Kathrin; Sic, Heiko; Rolink, Antonius; Eibel, Hermann; Rizzi, Marta

2014-02-01

240

The coexpression and clinical significance of costimulatory molecules B7-H1, B7-H3, and B7-H4 in human pancreatic cancer  

PubMed Central

Aim We investigated the expression of the inhibitory costimulatory molecules B7-H1, B7-H3, and B7-H4 in human pancreatic cancer to define their clinical significance and mechanism in a tumor microenvironment. Patients and methods Sixty-three pancreatic cancer tissues and 12 normal pancreatic tissues were examined in our research. Patients were enrolled in the study between December 2000 and August 2010. Expression levels of the B7 family of molecules and densities of tumor-infiltrating lymphocytes in the tissues were characterized with immunohistochemical assays. Results More than 50% of the patients expressed B7-H1 and B7-H4, and nearly 100% of the patients expressed B7-H3. B7-H1 expression was correlated with tumor size, B7-H3 expression was correlated with lymph-node metastasis and differentiation grade, and B7-H4 expression was correlated with tumor size, lymph-node metastasis, and invasion depth. High B7-H4 expression was also correlated with poor survival in pancreatic cancer. We determined the value of these three B7 family molecules in the postoperative survival prognosis for patients with pancreatic cancer, and pancreatic cancer patients with less coexpression of the B7 family of molecules had a significantly higher survival rate. B7-H1 expression was found to be negatively related to the intensity of both CD3+ T cells and CD8+ T cells, and B7-H4 expression was negatively related to CD3+ T-cell infiltration intensity, but not to CD8+ T cells. Conclusion B7-H1, B7-H3, and B7-H4 are involved in pancreatic cancer progression, and their coexpression could be a valuable prognostic indicator. Negative regulation of T-cell infiltration might be the main mechanism of action of the B7 family of molecules in pancreatic cancer. PMID:25170273

Chen, Yan; Sun, Jing; Zhao, Hua; Zhu, Dongming; Zhi, Qiaoming; Song, Shiduo; Zhang, Lifeng; He, Songbing; Kuang, Yuting; Zhang, Zixiang; Li, Dechun

2014-01-01

241

Use of viral pathogens and indicators to differentiate between human and non-human fecal contamination in a microbial source tracking comparison study  

Microsoft Academic Search

Assays for the detection and typing of adenoviruses, enteroviruses and F+ specific coliphages were performed on samples created as part of a national microbial source tracking methods comparison study. The samples were created blind to the researchers, and were inoculated with a variety of types of fecal contamination source (human, sewage, dog, seagull and cow) and mixtures of sources. Viral

Rachel T. Noble; Steven M. Allen; Angelia D. Blackwood; Weiping Chu; Sunny C. Jiang; Greg L. Lovelace; Mark D. Sobsey; Jill R. Stewart; Douglas A. Wait

2003-01-01

242

Effect of Cobalt60 Irradiation on Bradykinin B2 Receptor Expression on Human HF15 Cells  

Microsoft Academic Search

Bradykinin is a key mediator of pain and inflammation. Although radiotherapy has proven to be beneficial in the treatment of inflammatory disorders, the effect of irradiation on the bradykinin pathway in human cells has not been evaluated yet. Therefore, the aim of the study was to establish a human cell culture system and to analyze bradykinin B2 receptor expression in

Patrick Micke; Andree Blaukat; Oliver Micke

2003-01-01

243

Parametric decomposition of optic flow by humans Jose F. Barraza a,*, Norberto M. Grzywacz b  

E-print Network

Parametric decomposition of optic flow by humans Jose´ F. Barraza a,*, Norberto M. Grzywacz b that humans can precisely estimate parameters of these components, such as the angular velocity. However, this decomposition is such that the presence of the orthogonal component increases

Grzywacz, Norberto

244

H222c Introduction to Energy & Environment: Humans & Nature P. B. Rhines  

E-print Network

H222c Introduction to Energy & Environment: Humans & Nature P. B. Rhines spring 2012 Lecture 2 I. INTRODUCTION TO HUMANS AND ENERGY We will encounter several very different views of the environment during the 20th Century. The global use of energy from fossil fuels and renewable energies is about 4.0 x

245

Interactions of tricyclic antidepressant drugs with human and rat monoamine oxidase type B  

Microsoft Academic Search

The effect of tricyclic antidepressant drugs on the deamination of phenylethylamine and benzylamine by monoamine oxidase (MAO) type B was investigated in vitro in human brain cortex, human platelet, and rat brain preparations. These drugs inhibited MAO activity as expected; however, an atypical biphasic response was observed with the tertiary amine tricyclic, clomipramine, and, to a somewhat lesser extent, with

Audrey A. Reid; James L. Hill; Dennis L. Murphy

1988-01-01

246

Mixed-mode fracture of human cortical bone Elizabeth A. Zimmermann a,b  

E-print Network

homogeneous brittle materials. Specifically, in this orientation, the fracture toughness of bone is mark- edlyMixed-mode fracture of human cortical bone Elizabeth A. Zimmermann a,b , Maximilien E. Launey Available online 1 July 2009 Keywords: Human cortical bone Mixed-mode fracture Fracture toughness Fracture

Ritchie, Robert

247

Toward discovery science of human brain function Bharat B. Biswala  

E-print Network

, James J. Pekarx , Scott J. Peltiery , Steven E. Petersenz , Valentin Riedlaa , Serge A. R. B. Romboutsbb of Medicine, St. Louis, MO 63110; aa Departments of Neurology and Neuroradiology, Klinikum Rechts der Isar

Miall, Chris

248

B Cell Repertoire Analysis Identifies New Antigenic Domains on Glycoprotein B of Human Cytomegalovirus which Are Target of Neutralizing Antibodies  

Microsoft Academic Search

Human cytomegalovirus (HCMV), a herpesvirus, is a ubiquitously distributed pathogen that causes severe disease in immunosuppressed patients and infected newborns. Efforts are underway to prepare effective subunit vaccines and therapies including antiviral antibodies. However, current vaccine efforts are hampered by the lack of information on protective immune responses against HCMV. Characterizing the B-cell response in healthy infected individuals could aid

Sonja Pötzsch; Nadja Spindler; Anna-Katharina Wiegers; Tanja Fisch; Pia Rücker; Heinrich Sticht; Nina Grieb; Tina Baroti; Florian Weisel; Thomas Stamminger; Luis Martin-Parras; Michael Mach; Thomas H. Winkler

2011-01-01

249

Recollections of J.B.S. Haldane, with special reference to Human Genetics in India  

PubMed Central

This paper is a brief account of the scientific work of J.B.S. Haldane (1892–1964), with special reference to early research in Human Genetics. Brief descriptions of Haldane's background, his important contributions to the foundations of human genetics, his move to India from Great Britain and the research carried out in Human Genetics in India under his direction are outlined. Population genetic research on Y-linkage in man, inbreeding, color blindness and other aspects are described. PMID:22754215

Dronamraju, Krishna R.

2012-01-01

250

Voltage-Gated Na+ channel ?1B: a secreted cell adhesion molecule involved in human epilepsy  

PubMed Central

Scn1b null mice have a severe neurological and cardiac phenotype. Human mutations in SCN1B result in epilepsy and cardiac arrhythmia. SCN1B is expressed as two developmentally regulated splice variants, ?1 and ?1B, that are each expressed in brain and heart in rodents and humans. Here we studied the structure and function of ?1B and investigated a novel human SCN1B epilepsy-related mutation (p.G257R) unique to ?1B. We show that wild-type ?1B is not a transmembrane protein, but a soluble protein expressed predominantly during embryonic development that promotes neurite outgrowth. Association of ?1B with voltage-gated Na+ channels (VGSCs) Nav1.1 or Nav1.3 is not detectable by immunoprecipitation and ?1B does not affect Nav1.3 cell surface expression as measured by [3H]-saxitoxin binding. However, ?1B co-expression results in subtle alteration of Nav1.3 currents in transfected cells, suggesting that ?1B may modulate Na+ current in brain. Similar to the previously characterized p.R125C mutation, p.G257R results in intracellular retention of ?1B, generating a functional null allele. In contrast, two other SCN1B mutations associated with epilepsy, p.C121W and p.R85H, are expressed at the cell surface. We propose that ?1B p.G257R may contribute to epilepsy through a mechanism that includes intracellular retention resulting in aberrant neuronal pathfinding. PMID:21994374

Patino, G.A.; Brackenbury, W.J.; Bao, Y.; Lopez-Santiago, L. F.; O’Malley, H.A.; Chen, C.; Calhoun, J.D.; Lafrenière, R.G.; Cossette, P.; Rouleau, G.A.; Isom, L.L.

2011-01-01

251

Competitive chemiluminescent enzyme immunoassay for vitamin B12 analysis in human milk  

Technology Transfer Automated Retrieval System (TEKTRAN)

BACKGROUND Few accurate data exist on the concentration of vitamin B12 in human milk. Binding of the vitamin to haptocorrin (HC) can interfere with the assay if not removed by pretreatment, and very low values can occur in women with poor B12 status. This study evaluated two competitive enzyme bind...

252

Effects of Synephrine and B-Phenethylamine on Human a-Adrenoceptor Subtypes  

Technology Transfer Automated Retrieval System (TEKTRAN)

Synephrine and B-phenethylamine are structurally related to ephedrine. In this study, the effects of synephrine and B-phenethylamine are investigated on a-adrenoceptor (a-AR) subtypes expressed in human embroyonic kidney (HEK293) or Chinese hamster ovary (CHO) cells, and compared to that of 1R,2S-no...

253

Evaluation of different assays for the detection of parvovirus B19 DNA in human plasma  

Microsoft Academic Search

Human parvovirus B19 is a frequent contaminant of blood and plasma-derived medicinal products and transmission of this virus has been shown to occur through the administration of contaminated products. Inactivation of the virus has proved difficult and as a consequence, manufacturers of blood products have implemented screening measures to reduce the load of parvovirus B19 in manufacturing plasma pools by

Sally A. Baylis; Nita Shah; Philip D. Minor

2004-01-01

254

Comparison of 17 isolates of the human parvovirus B 19 by restriction enzyme analysis  

Microsoft Academic Search

Summary The genomes of 17 isolates of the human parvovirus B 19 were compared by restriction with eight endonucleases. All but four isolates proved indistinguishable. A 3.2kb B 19 DNA fragment was cloned and used as a molecular probe.

F. Morinet; J.-D. Tratschin; Y. Perol; G. Siegl

1986-01-01

255

Human Group B Rotavirus Infections Cause Severe Diarrhea in Children and Adults in Bangladesh  

PubMed Central

Human group B rotavirus was detected in 12 of 220 adult patients and 2 of 67 child patients with severe diarrhea in Bangladesh. Group B rotavirus may be virulent in both adults and children, and the virus may be an especially serious diarrheal agent in Bangladesh. PMID:12734276

Sanekata, Takeshi; Ahmed, Muzahed Uddin; Kader, Abdul; Taniguchi, Koki; Kobayashi, Nobumichi

2003-01-01

256

Hypotension in Transgenic Mice Overexpressing Human Bradykinin B2 Receptor  

Microsoft Academic Search

Bradykmm binds to its receptor at target organs and exerts a wide spectrum of biological actlvlties including va- sodllation, smooth muscle contraction and relaxation, pain, and mflammatlon To gam a better mslght mto the physlologlcal func- tion of this potent vasoactlve peptlde, we created transgenic mice that harbor the human bradykmm Bz receptor transgene under the control of the Rous

Dan-zhao Wang; Lee Chao; Juhe Chao

257

Human Resource Development and Manpower Training. Paper Presentations: Session B.  

ERIC Educational Resources Information Center

This document contains 18 papers from the human resource development and manpower training section of an international conference on vocational education and training (VET) for lifelong learning in the information era. The following papers are included: "Use of Social and Economic Modeling to Plan Vocational Education and Training" (David L.…

2000

258

NF?B and AP-1 Drive Human Myometrial IL8 Expression  

PubMed Central

The uterine expression of the chemokine IL8 increases dramatically with the onset of labour both at term and preterm. The IL8 promoter contains binding sites for the transcription factors nuclear factor-kappa B (NF?B), activator protein-1 (AP-1), and CCAAT/enhancer-binding protein (CEBP). In this study we investigated the roles of these transcription factors in IL1B regulation of the IL8 gene in human myometrium. Using chromatin immune precipitation (ChIP) assay, we showed that each of NF?B, CEBP, and AP-1 binds to the IL8 promoter upon IL1B stimulation. To examine the relative importance of each site in IL8 gene expression, site-directed mutagenesis of each of these sites was performed. We found that the NF?B site was essential for basal and IL1B-stimulated gene expression. Mutation of the AP-1 site reduced both basal and IL1B-stimulated expression but to a lesser extent. Mutation of the CEBP site had no effect upon basal expression but eliminated the IL1B response. Small interfering RNA (siRNA) silencing of NF?B abolished the IL8 response to IL1B significantly; siRNA against AP-1 reduced it to a lesser extent whilst knockdown of CEBP enhanced the response. Our data confirms a central and essential role for NF?B in regulation of IL8 in human myometrium. PMID:22685373

Khanjani, Shirin; Terzidou, Vasso; Johnson, Mark R.; Bennett, Phillip R.

2012-01-01

259

Interrelationship of active and latent secreted human cathepsin B precursors.  

PubMed Central

Two high-Mr forms of cathepsin B have been described previously, both of which are stable at alkaline pH, in contrast with the lysosomal proteinase. One form is latent and activated by pepsin treatment; the other form is active as measured with synthetic substrates. In the present study it was shown that the two forms are indistinguishable on the basis of molecular size as determined by gel-filtration chromatography or sodium dodecyl sulphate/polyacrylamide-gel electrophoresis followed by immunoblotting. Both forms lose their alkali-stability upon exposure to Hg2+, and after Hg2+ treatment the latent form becomes immuneprecipitable by an antiserum that reacts only with denatured cathepsin B. Lysosomal cathepsin B is bound by the plasma proteinase inhibitor alpha 2-macroglobulin, a process that requires proteolytic cleavage of the inhibitor. In contrast, the stable active form of cathepsin B is not bound by this inhibitor unless this enzyme is first destabilized by Hg2+ treatment. These results indicate that cathepsin B exists in three different states of activity, completely latent, partially active and fully proteolytically active. To exhibit true endopeptidase activity it seems that the enzyme must be in an alkali-unstable form. Images Fig. 1. Fig. 3. PMID:2420324

Mort, J S; Recklies, A D

1986-01-01

260

Monoclonal antibodies IPO-3 and IPO-10 against human B cell differentiation antigens.  

PubMed

Monoclonal antibodies (mAbs) IPO-3 and IPO-10 were generated following immunization of a BALB/c mice with human cell lines RPMI-1788 and Daudi respectively. The reactivity of these mAbs was studied by indirect immunofluorescence technique with 10 human cell lines, blood cells of healthy persons and patients with the malignant lymphoproliferative diseases. Studies of normal and neoplastic B cells suggest that mAbs IPO-3 and IPO-10 which recognize antigens are B lineage restricted. The presence of an antigen defined by the mAb IPO-10 appears to include most but not all the stages of B cell differentiation, whereas IPO-3 detected antigen is not represented on resting B cells and has a very limited expression on activated B lymphocytes. The results obtained with mAbs IPO-3 and IPO-10 are discussed in relation to other known B cell surface markers. PMID:3265315

Pinchouk, V G; Sidorenko, S P; Gluzman, D F; Vetrova, E P; Berdova, A G; Schlapatskaya, L N

1988-01-01

261

A cell type-specific enhancer in the human B7.1 gene regulated by NF- kappaB  

PubMed Central

The costimulatory molecule B7.1 provides a second signal critical for T cell activation. The distribution of this integral membrane protein is restricted to certain tissues where its level of expression is modulated by multiple exogenous stimuli. To identify the molecular basis for specificity and inducibility, the chromatin configuration of the human B7.1 gene was examined in intact nuclei from various cell types. The identification of a tissue-specific deoxyribonuclease I hypersensitive site approximately 3kb upstream of the transcription start site led to the characterization of a cell type-specific enhancer region. This 183-bp region was both cell type specific and responsive to two distinct stimuli, lipopolysaccharide and dibutyryl cAMP, known to regulate B7.1 expression. Deletional and site-directed mutagenesis revealed the presence of multiple functionally critical cis elements within this region, one of which was a nuclear factor (NF)-kappaB consensus sequence. In B7.1-positive B cells, this element bound several members of the NF-kappaB family, transcription factors already implicated in signal transduction pathways relevant to B7.1 expression. This is the first description, to our knowledge, of regulatory elements that control expression of a gene encoding a B7 costimulatory molecule. PMID:8642282

1996-01-01

262

Human innate B cells: a link between host defense and autoimmunity?  

PubMed Central

B cells play a variety of immunoregulatory roles through their antigen-presentation ability and through cytokine and chemokine production. Innate immune activation of B cells may play a beneficial role through the generation of natural cross-reactive antibodies, by maintaining B cell memory and by exercising immunomodulatory functions that may provide protection against autoimmunity. In this article, we review human B cell populations and their functional properties, with a particular focus on a population of inherently autoreactive B cells, which seem to play an important physiological role in innate immunity, but which, if selected into adaptive immune responses, appear to become pathogenic agents in systemic lupus erythematosus. PMID:15633016

Milner, Eric C. B.; Anolik, Jennifer; Cappione, Amedeo; Sanz, Iñaki

2005-01-01

263

Kikuchi-Fujimoto lymphadenitis: role of parvovirus B-19, Epstein-Barr virus, human herpesvirus 6, and human herpesvirus 8.  

PubMed

Kikuchi-Fujimoto lymphadenitis is a self-limited disorder that typically presents in young females as painless cervical lymphadenopathy with fever, anemia, and leukopenia. The clinical manifestations and pathologic findings suggest a viral etiology, yet specific etiologic agents remain unknown. Although there are studies reporting positive associations between Kikuchi-Fujimoto lymphadenitis and parvovirus B19 and herpesviruses, other studies have failed to find an association with these viruses. To our knowledge, this current study is the largest study of Kikuchi-Fujimoto lymphadenitis in Western patients that used polymerase chain reaction testing for 4 different common viral pathogens often implicated as etiologic agents in Kikuchi-Fujimoto lymphadenitis. Archival material from 3 institutions was included, following confirmation of the diagnosis of Kikuchi-Fujimoto lymphadenitis by 2 independent pathologists. Polymerase chain reaction from the paraffin-embedded tissue sections for parvovirus B19, Epstein-Barr virus, human herpesvirus 6, and human herpesvirus 8 was performed. Eighteen cases of Kikuchi-Fujimoto lymphadenitis were analyzed, 12 of which (60%) were cervical lymph nodes. All the cases showed typical geographic necrosis with abundant apoptotic debris, although the degree of necrosis was variable. Polymerase chain reaction revealed a high prevalence of parvovirus B19 in the controls (44%); there were fewer positive cases seen in the Kikuchi-Fujimoto lymphadenitis cases (11%), but this did not reach statistical significance (P = .25).There were no significant differences between cases and controls in the prevalence of Epstein-Barr virus, human herpesvirus 6, and human herpesvirus 8 (P = .50 for all 3). Polymerase chain reaction failed to reveal a positive association between Kikuchi-Fujimoto lymphadenitis and 4 common suspected viral agents. These findings do not support a role for Epstein-Barr virus, human herpesvirus 6, human herpesvirus 8, or parvovirus B19 in the pathogenesis of Kikuchi-Fujimoto lymphadenitis. PMID:22939574

Rosado, Flavia Guimaraes Nunes; Tang, Yi-Wei; Hasserjian, Robert Paul; McClain, Colt M; Wang, Beverly; Mosse, Claudio A

2013-02-01

264

Human ACE and bradykinin B2 receptors form a complex at the plasma membrane  

Microsoft Academic Search

To investigate how angiotensin I-con- verting enzyme (ACE) inhibitors enhance the actions of bradykinin (BK) on B2 receptors independent of block- ing BK inactivation, we expressed human somatic ACE and B2 receptors in CHO cells. Bradykinin and its ACE-resistant analog were the receptor agonists. B2 fused with green fluorescent protein (GFP) and ACE were coprecipitated with antisera to GFP or

Zhenlong Chen; Peter A. Deddish; Richard D. Minshall; Robert P. Becker; Ervin G. Erdos; Fulong Tan

2006-01-01

265

NF-kappaB blockade and oncogenic Ras trigger invasive human epidermal neoplasia  

Microsoft Academic Search

The nuclear factor NF-kappaB and oncogenic Ras can alter proliferation in epidermis, the most common site of human cancer. These proteins are implicated in epidermal squamous cell carcinoma in mice, however, the potential effects of altering their function are uncertain. Whereas inhibition of NF-kappaB enhances apoptosis in certain tumours, blockade of NF-kappaB predisposes murine skin to squamous cell carcinoma. Because

Maya Dajee; Mirella Lazarov; Jennifer Y. Zhang; Ti Cai; Cheryl L. Green; Alan J. Russell; M. Peter Marinkovich; Shiying Tao; Qun Lin; Yoshiaki Kubo; Paul A. Khavari

2003-01-01

266

Molecular and structural characterization of fluorescent human parvovirus B19 virus-like particles  

Microsoft Academic Search

Although sharing a T=1 icosahedral symmetry with other members of the Parvoviridae family, it has been suggested that the fivefold channel of the human parvovirus B19 VP2 capsids is closed at its outside end. To investigate the possibility of placing a relatively large protein moiety at this site of B19, fluorescent virus-like particles (fVLPs) of B19 were developed. The enhanced

Leona Gilbert; Jouni Toivola; Daniel White; Teemu Ihalainen; Wesley Smith; Laura Lindholm; Matti Vuento; Christian Oker-Blom

2005-01-01

267

Molecular cloning of cDNA for CENP-B, the major human centromere autoantigen  

Microsoft Academic Search

We have isolated a series of overlapping cDNA clones for ~95 % of the mRNA that encodes CENP-B, the 80-kD human centromere autoantigen recognized by patients with anticentromere antibodies. The cloned sequences encode a polypeptide with an apparent molecular mass appropriate for CENP-B. This polypeptide and CENP-B share three non-over- lapping epitopes. The first two are defined by monoclonal antibodies

William C. Earnshaw; Kevin E Sullivan; Paula S. Machlin; Carol A. Cooke; Donald A. Kaiser; Thomas D. Pollard; Naomi E Rothfield; Don W. Cleveland

1987-01-01

268

[IPO-10 monoclonal antibodies to the human B-lymphocyte differentiation antigen].  

PubMed

Monoclonal antibodies IPO-10 were generated following immunization of a BALB/c mice with human cell line Daudi. Reactivity of this mABs was studied by indirect immunofluorescence technique with 10 human cell lines, blood cells of healthy persons and of patients with the malignant lymphoproliferative diseases. Studies on normal and neoplastic B cell suggest that mABs IPO-10 recognizing antigen is B lineage restricted. The antigen defined by the mAb IPO-10 appear to include most but not all stages of B cell differentiation. PMID:2457482

Sidorenko, S P; Vetrova, E P; Berdova, A G; Shlapatskaia, L N; Evsev'eva, A I

1988-01-01

269

Quantitative Detection of Hepatitis A Virus and Enteroviruses Near the United States-Mexico Border and Correlation with Levels of Fecal Indicator Bacteria?  

PubMed Central

For decades, untreated sewage flowing northward from Tijuana, Mexico, via the Tijuana River has adversely affected the water quality of the recreational beaches of San Diego, California. We used quantitative reverse transcription-PCR to measure the levels of hepatitis A virus (HAV) and enteroviruses in coastal waters near the United States-Mexico border and compared these levels to those of the conventional fecal indicators, Escherichia coli and enterococci. Over a 2-year period from 2003 to 2005, a total of 20 samples were assayed at two sites during both wet and dry weather: the surfzone at the mouth of the Tijuana River and the surfzone near the pier at Imperial Beach (IB), California (about 2 km north of the mouth of the Tijuana River). HAV and enterovirus were detected in 79 and 93% of the wet-weather samples, respectively. HAV concentrations in these samples ranged from 105 to 30,771 viral particles/liter, and enterovirus levels ranged from 7 to 4,417 viral particles/liter. The concentrations of HAV and enterovirus were below the limit of detection for all dry weather samples collected at IB. Regression analyses showed a significant correlation between the densities of both fecal bacterial indicators and the levels of HAV (R2 > 0.61, P < 0.0001) and enterovirus (R2 > 0.70, P < 0.0001), a finding that supports the use of conventional bacterial indicators to predict the levels of these viruses in recreational marine waters. PMID:16980430

Gersberg, Richard M.; Rose, Michael A.; Robles-Sikisaka, Refugio; Dhar, Arun K.

2006-01-01

270

Human bradykinin B2 receptor: Nucleotide sequence analysis and assignment to chromosome 14  

SciTech Connect

Functional cDNA clones for human bradykinin B2 receptor were isolated from uterus RNA by a polymerase chain reaction (PCR)-based method and by screening a human cosmid library with rat bradykinin B2 receptor probe. We isolated several overlapping clones from the cosmid library, each of which encodes the entire protein-coding sequence. The human bradykinin B2 receptor gene codes for a 364-amino-acid protein with a molecular mass of 41,442 Da that is highly homologous to rat bradykinin B2 receptor cDNA (81%). The entire human cDNA sequence was cloned into an expression vector and mRNA was synthesised by in vitro transcription. Applications of bradykinin caused membrane current responses in Xenopus oocytes injected with the in vitro-synthesized mRNA. Preincubation with the potent B2 antagonist, HOE140, prevented this response. The genomic clone is intronless, and we have identified an upstream promoter region and a downstream polyadenylation signal. The human bradykinin B2 receptor gene has been mapped to chromosome 14 using PCR to specifically amplify DNA from somatic cell hybrids. 10 refs., 1 fig., 1 tab.

Powell, S.J.; Slynn, G.; Thomas, C.; Hopkins, B.; Briggs, I.; Graham, A. (ICI Pharmaceuticals, Cheshire (United Kingdom))

1993-02-01

271

Intrinsic differences in the initiation of B cell receptor signaling favor responses of human IgG+ memory B cells over IgM+ naïve B cells  

PubMed Central

The acquisition of long-lived memory B cells (MBCs) is critical for the defense against many infectious diseases. Despite their importance, little is known about how antigens (Ags) trigger human MBCs, even though our understanding of the molecular basis of Ag activation of B cells in model systems has advanced considerably. Here, we use quantitative, high-resolution, live cell imaging at the single cell and single molecule levels to describe the earliest Ag-driven events in human isotype-switched, IgG-expressing MBCs and compare them to those in IgM-expressing naïve B cells. We show that human MBCs are more robust than naïve B cells at each step in the initiation of B cell receptor (BCR) signaling, including interrogation of Ag-containing membranes, formation of sub-microscopic BCR oligomers and recruitment and activation of signaling-associated kinases. Despite their robust response to Ag, MBCs remain highly sensitive to Fc?RIIB-mediated inhibition. We also demonstrate that in the absence of Ag, a portion of MBC receptors spontaneously oligomerized and phosphorylated kinases accumulated at the membrane and speculate that heightened constitutive signaling may play a role in maintaining MBC longevity. Using high-resolution imaging we have provided a description of the earliest events in the Ag activation of MBCs and evidence for acquired cell-intrinsic differences in the initiation of BCR signaling in human naïve and MBCs. PMID:22379037

Davey, Angel M.; Pierce, Susan K.

2012-01-01

272

EVALUATION OF MIXED CELL TYPES AND 5-IODO-2'-DEOXYURIDINE TREATMENT UPON PLAQUE ASSAY TITERS OF HUMAN ENTERIC VIRUSES (JOURNAL VERSION)  

EPA Science Inventory

Four continuous cell lines BGM, L-132, HEL-299, and RD were compared both when cultured separately and as mixtures for use in plaque assay titrations of human Adenovirus 1 and six human enterovirus serotypes. The effect of incubating these cell cultures in media containing IDU (5...

273

High Levels of SOX5 Decrease Proliferative Capacity of Human B Cells, but Permit Plasmablast Differentiation  

PubMed Central

Currently very little is known about the differential expression and function of the transcription factor SOX5 during B cell maturation. We identified two new splice variants of SOX5 in human B cells, encoding the known L-SOX5B isoform and a new shorter isoform L-SOX5F. The SOX5 transcripts are highly expressed during late stages of B-cell differentiation, including atypical memory B cells, activated CD21low B cells and germinal center B cells of tonsils. In tonsillar sections SOX5 expression was predominantly polarized to centrocytes within the light zone. After in vitro stimulation, SOX5 expression was down-regulated during proliferation while high expression levels were permissible for plasmablast differentiation. Overexpression of L-SOX5F in human primary B lymphocytes resulted in reduced proliferation, less survival of CD138neg B cells, but comparable numbers of CD138+CD38hi plasmablasts compared to control cells. Thus, our findings describe for the first time a functional role of SOX5 during late B cell development reducing the proliferative capacity and thus potentially affecting the differentiation of B cells during the germinal center response. PMID:24945754

Rakhmanov, Mirzokhid; Sic, Heiko; Kienzler, Anne-Kathrin; Fischer, Beate; Rizzi, Marta; Seidl, Maximilian; Melkaoui, Kerstina; Unger, Susanne; Moehle, Luisa; Schmit, Nadine E.; Deshmukh, Sachin D.; Ayata, Cemil Korcan; Schuh, Wolfgang; Zhang, Zhibing; Cosset, François-Loic; Verhoeyen, Els; Peter, Hans-Hartmut; Voll, Reinhard E.; Salzer, Ulrich

2014-01-01

274

High levels of SOX5 decrease proliferative capacity of human B cells, but permit plasmablast differentiation.  

PubMed

Currently very little is known about the differential expression and function of the transcription factor SOX5 during B cell maturation. We identified two new splice variants of SOX5 in human B cells, encoding the known L-SOX5B isoform and a new shorter isoform L-SOX5F. The SOX5 transcripts are highly expressed during late stages of B-cell differentiation, including atypical memory B cells, activated CD21low B cells and germinal center B cells of tonsils. In tonsillar sections SOX5 expression was predominantly polarized to centrocytes within the light zone. After in vitro stimulation, SOX5 expression was down-regulated during proliferation while high expression levels were permissible for plasmablast differentiation. Overexpression of L-SOX5F in human primary B lymphocytes resulted in reduced proliferation, less survival of CD138neg B cells, but comparable numbers of CD138+CD38hi plasmablasts compared to control cells. Thus, our findings describe for the first time a functional role of SOX5 during late B cell development reducing the proliferative capacity and thus potentially affecting the differentiation of B cells during the germinal center response. PMID:24945754

Rakhmanov, Mirzokhid; Sic, Heiko; Kienzler, Anne-Kathrin; Fischer, Beate; Rizzi, Marta; Seidl, Maximilian; Melkaoui, Kerstina; Unger, Susanne; Moehle, Luisa; Schmit, Nadine E; Deshmukh, Sachin D; Ayata, Cemil Korcan; Schuh, Wolfgang; Zhang, Zhibing; Cosset, François-Loic; Verhoeyen, Els; Peter, Hans-Hartmut; Voll, Reinhard E; Salzer, Ulrich; Eibel, Hermann; Warnatz, Klaus

2014-01-01

275

Expression of Cholesterol Sulfotransferase (SULT2B1b) in Human Platelets  

Microsoft Academic Search

Background—Cholesterol sulfate, the most important sterol sulfate in the human circulation, has emerged as a multifaceted molecule. Among its many demonstrated regulatory actions is its ability to influence blood clotting and fibrinolysis. Additionally, cholesterol sulfate is a constituent of human platelets, where it has been shown to support platelet aggregation. Methods and Results—We have documented the presence of the enzyme

Hidekatsu Yanai; Norman B. Javitt; Yuko Higashi; Hirotoshi Fuda; Charles A. Strott

2010-01-01

276

Immunocytochemical localization of monoamine oxidases A and B in human peripheral tissues and brain.  

PubMed

Monoamine oxidases (MAO; EC 1.4.3.4.) A and B occur in the outer mitochondrial membrane and oxidize a number of important biogenic and xenobiotic amines. Monoclonal antibodies specific for human MAO A or B and immunocytochemical techniques were used to visualize the respective enzymes in human placenta, platelets, lymphocytes, liver, brain, and a human hepatoma cell line. MAO A was observed in the syncytiotrophoblast layer of term placenta, liver, and a subset of neurons in brain, but was not observed in platelets or lymphocytes, which are known to lack type A enzyme. MAO B was observed in platelets, lymphocytes, and liver, but not in placenta, which contains little or no MAO B. MAO B was also observed in a subset of neurons in the brain that was distinct from that which contained MAO A. MAO A and MAO B were also observed in some glia. Unlike most tissues examined, liver cells appeared to contain both forms of the enzyme. These studies show that MAO A and MAO B can be specifically visualized by immunocytochemical means in a variety of human cells and tissues and can provide a graphic demonstration of the high degree of cell specificity of expression of the two forms of the enzyme. PMID:3025289

Thorpe, L W; Westlund, K N; Kochersperger, L M; Abell, C W; Denney, R M

1987-01-01

277

Human peripheral blood B-cell compartments: a crossroad in B-cell traffic.  

PubMed

A relatively high number of different subsets of B-cells are generated through the differentiation of early B-cell precursors into mature B-lymphocytes in the bone marrow (BM) and antigen-triggered maturation of germinal center B-cells into memory B-lymphocytes and plasmablasts in lymphoid tissues. These B-cell subpopulations, which are produced in the BM and lymphoid tissues, recirculate through peripheral blood (PB), into different tissues including mucosa and the BM, where long-living plasma cells produce antibodies. These circulating PB B-cells can be classified according to their maturation stage into i) immature/transitional, ii) naïve, and iii) memory B-lymphocytes, and iv) plasmablasts/plasma cells. Additionally, unique subsets of memory B-lymphocytes and plasmablasts/plasma cells can be identified based on their differential expression of unique Ig-heavy chain isotypes (e.g.: IgM, IgD, IgG, IgA). In the present paper, we review recent data reported in the literature about the distribution, immunophenotypic and functional characteristics of these cell subpopulations, as well as their distribution in PB according to age and seasonal changes. Additional information is also provided in this regard based on the study of a population-based cohort of 600 healthy adults aged from 20 to 80 years, recruited in the Salamanca area in western Spain. Detailed knowledge of the distribution and traffic of B-cell subsets through PB mirrors the immune status of an individual subject and it may also contribute to a better understanding of B-cell disorders related to B-cell biology and homeostasis, such as monoclonal B-cell lymphocytosis (MBL). PMID:20839338

Perez-Andres, M; Paiva, B; Nieto, W G; Caraux, A; Schmitz, A; Almeida, J; Vogt, R F; Marti, G E; Rawstron, A C; Van Zelm, M C; Van Dongen, J J M; Johnsen, H E; Klein, B; Orfao, A

2010-01-01

278

Expression of human {beta}-defensin-2 gene induced by CpG-DNA in human B cells  

SciTech Connect

Defensins have a broad range of antimicrobial activity against bacteria, fungi, and viruses. The expression of human {beta}-defensin-2 (hBD-2) is prevalently observed in epithelial cells and is induced by bacterial infection. Here, we have shown that the expression of the hBD-2 gene and release of hBD-2 protein into the medium is up-regulated in response to CpG-DNA in human B cell line RPMI 8226. The induction of hBD-2 was dependent on CG sequence and phosphorothioate backbone-modification. This was also confirmed in primary human lymphocytes. To shed light on the molecular mechanism involved in hBD-2 induction by CpG-DNA, we examined the contribution of the NF-{kappa}B signaling pathway in RPMI 8226 cells. Suppression of MyD88 function and inhibition of NF-{kappa}B nuclear localization blocked hBD-2 induction. The NF-{kappa}B pathway inhibitors also abolished hBD-2 induction. These results may contribute to a better understanding on the therapeutic effects of CpG-DNA against infectious diseases.

Han, Su Ho [Department of Microbiology, College of Medicine, Hallym University, Gangwon-do 200-702 (Korea, Republic of)] [Department of Microbiology, College of Medicine, Hallym University, Gangwon-do 200-702 (Korea, Republic of); Kim, Young-Eun; Park, Jeong-A [Department of Biochemistry, College of Natural Sciences, Chungbuk National University, Chungbuk 361-763 (Korea, Republic of)] [Department of Biochemistry, College of Natural Sciences, Chungbuk National University, Chungbuk 361-763 (Korea, Republic of); Park, Jae-Bong [Department of Biochemistry, College of Medicine, Hallym University, Gangwon-do 200-702 (Korea, Republic of)] [Department of Biochemistry, College of Medicine, Hallym University, Gangwon-do 200-702 (Korea, Republic of); Kim, Yong-Sun [Department of Microbiology, College of Medicine, Hallym University, Gangwon-do 200-702 (Korea, Republic of)] [Department of Microbiology, College of Medicine, Hallym University, Gangwon-do 200-702 (Korea, Republic of); Lee, Younghee [Department of Biochemistry, College of Natural Sciences, Chungbuk National University, Chungbuk 361-763 (Korea, Republic of)] [Department of Biochemistry, College of Natural Sciences, Chungbuk National University, Chungbuk 361-763 (Korea, Republic of); Choi, Ihn-Geun [Department of Neuropsychiatry, Hallym University, Han-Gang Sacred Heart Hospital, Seoul 150-719 (Korea, Republic of)] [Department of Neuropsychiatry, Hallym University, Han-Gang Sacred Heart Hospital, Seoul 150-719 (Korea, Republic of); Kwon, Hyung-Joo, E-mail: hjookwon@hallym.ac.kr [Department of Microbiology, College of Medicine, Hallym University, Gangwon-do 200-702 (Korea, Republic of) [Department of Microbiology, College of Medicine, Hallym University, Gangwon-do 200-702 (Korea, Republic of); Center for Medical Science Research, College of Medicine, Hallym University, Gangwon-do 200-702 (Korea, Republic of)

2009-11-20

279

A human centromere antigen (CENP-B) interacts with a short specific sequence in alphoid DNA, a human centromeric satellite  

PubMed Central

We report the interaction between a human centromere antigen and an alphoid DNA, a human centromeric satellite DNA, which consists of 170- bp repeating units. A cloned alphoid DNA fragment incubated with a HeLa cell nuclear extract is selectively immunoprecipitated by the anticentromere sera from scleroderma patients. Immunoprecipitation of the DNA made by primer extension defines the 17-bp segment on the alphoid DNA that is required for formation of DNA-antigen complex. On the other hand, when proteins bound to the biotinylated alphoid DNA carrying the 17-bp motif are recovered by streptavidin agarose and immunoblotted, the 80-kD centromere antigen (CENP-B) is detected. DNA binding experiments for proteins immunoprecipitated with anticentromere serum, separated by gel electrophoresis, and transferred to a membrane strongly suggest that the 80-kD antigen specifically binds to the DNA fragment with the 17-bp motif. The 17-bp motif is termed the "CENP-B box." Alphoid monomers with the CENP-B box are found in all the known alphoid subclasses, with varying frequencies, except the one derived from the Y chromosome so far cloned. These results imply that the interaction of the 80-kD centromere antigen with the CENP-B box in the alphoid repeats may play some crucial role in the formation of specified structure and/or function of human centromere. PMID:2808515

1989-01-01

280

Complementary methods provide evidence for the expression of CXCR7 on human B cells.  

PubMed

PTMs of extracellular domains of membrane proteins can influence antibody binding and give rise to ambivalent results. Best proof of protein expression is the use of complementary methods to provide unequivocal evidence. CXCR7, a member of the atypical chemokine receptor family, mainly functions as scavenger for the chemokines CXCL12 and CXCL11. The expression of CXCR7 on nonhematopoietic cells and neoplasms is widely accepted, however, its expression on leukocytes was recently challenged. To solve the dissent, we thoroughly analyzed the expression of CXCR7 on human B cells. We validated the efficiency of different epitope-specific monoclonal antibodies to detect CXCR7 on transfected cells and primary human B cells. The specificity of the used antibodies was further confirmed by an experimentally independent double labeling approach. Examination of CXCR7-dependent scavenging of fluorescent-labeled CXCL12 revealed functional expression of the receptor on human B cells. Moreover, real-time PCR analysis of CXCR7 mRNA showed the presence of transcripts in human leukocytes. Finally, two CXCR7-specific peptides were identified by MS in immunoprecipitates from primary human B cells. Thus, we present a strategy based on combined proteomic and functional approaches that can be used to solve dissents on protein expression, i.e. demonstrating the expression of CXCR7 on human leukocytes. PMID:22623068

Humpert, Marie-Luise; Tzouros, Manuel; Thelen, Sylvia; Bignon, Alexandre; Levoye, Angélique; Arenzana-Seisdedos, Fernando; Balabanian, Karl; Bachelerie, Françoise; Langen, Hanno; Thelen, Marcus

2012-06-01

281

Enterovirus 71 induces degradation of TRIM38, a potential E3 ubiquitin ligase  

Microsoft Academic Search

Background  The tripartite motif (TRIM) proteins are a family of more than 70 members in human. However, only a few of them have been\\u000a well studied. The TRIM proteins contain the conserved RING, B-box, coiled-coil, and SPRY domains, most of which are involved\\u000a in protein ubiquitination. TRIM38 is a member of the TRIM protein family, which we studied in more detail

Xinlei Liu; Xiaobo Lei; Zhuo Zhou; Zhenmin Sun; Qinghua Xue; Jianwei Wang; Tao Hung

2011-01-01

282

[The expression, purification and characterization of human His-ATG4B protein].  

PubMed

Objective To construct the prokaryotic expression vector of human autophagy-related protein 4 homolog B (ATG4B) labeled with His-tag, obtain the purified His-ATG4B protein, and identify its activity preliminarily. Methods ATG4B coding region was amplified from human mammary gland cDNA library by PCR, and was cloned into the prokaryotic expression vector pET-28a(+). After verification by enzyme digestion, the correct recombinant plasmid His-ATG4B was introduced into E.coli Rossate. The expressed recombinant plasmid was purified by Ni-NTA beads and identified by SDS-PAGE and Western blot analysis. The function of the purified protein His-ATG4B was detected by GST pull-down assay. Results The DNA fragment of about 1100 bp was successfully amplified from human mammary gland cDNA by PCR, and inserted into pET-28a vector correctly. The results of double digestion and sequencing suggested that the His-ATG4B recombinant plasmid was successfully obtained. His-ATG4B protein of about Mr 47 000 was induced and identified by SDS-PAGE analysis. GST pull-down assay showed that His-ATG4B could interact with LC3B in vitro, suggesting that it has a good biological function. Conclusion The prokaryotic expression protein of His-ATG4B has been obtained successfully, which lays a foundation for further research on the function of ATG4B in autophagy. PMID:25652856

Huang, Rong; Xu, Xiaojie; Liang, Yingchun; Zhang, Li; Wang, Tao; Zhou, Liying; DU, Nan; Ye, Qinong

2015-02-01

283

Spi-B inhibits human plasma cell differentiation by repressing BLIMP1 and XBP-1 expression  

PubMed Central

The terminal differentiation of B cells into antibody-secreting plasma cells is tightly regulated by a complex network of transcription factors. Here we evaluated the role of the Ets factor Spi-B during terminal differentiation of human B cells. All mature tonsil and peripheral blood B-cell subsets expressed Spi-B, with the exception of plasma cells. Overexpression of Spi-B in CD19+ B cells inhibited, similar to the known inhibitor BCL-6, the expression of plasma cell–associated surface markers and transcription factors as well as immunoglobulin production, ie, in vitro plasma cell differentiation. The arrest in B-cell differentiation enforced by Spi-B was independent of the transactivation domain, but dependent on the Ets-domain. By chromatin immunoprecipitation and assays using an inducible Spi-B construct BLIMP1 and XBP-1 were identified as direct target genes of Spi-B mediated repression. We propose a novel role for Spi-B in maintenance of germinal center and memory B cells by direct repression of major plasma cell factors and thereby plasma cell differentiation. PMID:18552212

Schmidlin, Heike; Diehl, Sean A.; Nagasawa, Maho; Scheeren, Ferenc A.; Schotte, Remko; Uittenbogaart, Christel H.; Spits, Hergen

2008-01-01

284

Monoclonal antibodies to monoamine oxidase B and another mitochondrial protein from human liver.  

PubMed Central

A monoclonal antibody has been generated to human liver monoamine oxidase (MAO) B by fusion of mouse myeloma cells with spleen cells from a mouse immunized with a mixture of semi-purified MAO A and MAO B. The antibody, 3F12/G10, an immunoglobulin G1, reacts with its antigen in cryostat sections of human liver, showing an intracellular particulate distribution as demonstrated by immunoperoxidase staining. The antibody indirectly precipitates [3H]pargyline-labelled human MAO B both from liver and platelet extracts but fails to precipitate MAO A from liver extracts. The antibody does not recognise rat liver MAO B, showing that the determinant is not universally expressed on MAO B. The antibody has no effect on the catalytic activity of MAO B. Other monoclonal antibodies were generated but they are directed to a protein with a subunit Mr of 54 000, a contaminant of the MAO preparation. One of these antibodies, A8/C2, an IgG2a, reacts with the same protein in both rat and human liver extracts. Images Fig. 1. Fig. 3. PMID:3527152

Billett, E E; Mayer, R J

1986-01-01

285

Structures of human monoamine oxidase B complexes with selective noncovalent inhibitors: safinamide and coumarin analogs.  

PubMed

Structures of human monoamine oxidase B (MAO B) in complex with safinamide and two coumarin derivatives, all sharing a common benzyloxy substituent, were determined by X-ray crystallography. These compounds competitively inhibit MAO B with Ki values in the 0.1-0.5 microM range that are 30-700-fold lower than those observed with MAO A. The inhibitors bind noncovalently to MAO B, occupying both the entrance and the substrate cavities and showing a similarly oriented benzyloxy substituent. PMID:17915852

Binda, Claudia; Wang, Jin; Pisani, Leonardo; Caccia, Carla; Carotti, Angelo; Salvati, Patricia; Edmondson, Dale E; Mattevi, Andrea

2007-11-15

286

Chromosomal localization of the human apolipoprotein B gene and detection of homologous RNA in monkey intestine  

SciTech Connect

A cDNA clone of the human apolipoprotein B-100 was used as a hybridization probe to detect homologous sequences in both flow-sorted and in situ metaphase chromosomes. The results indicate that the gene encoding this protein is on the distal end of the short arm of chromosome 2 (2p23-2p24). RNA isolated from monkey small intestine contained sequences (6.5 and 18 kilobases) homologous to the cDNA of apolipoprotein B-100. These results are consistent with the hypothesis that one gene codes for both the intestinal (B-48) and the hepatic (B-100) forms.

Deeb, S.S.; Disteche, C.; Motulsky, A.G.; Lebo, R.V.; Kan, Y.W.

1986-01-01

287

Rapid and highly sensitive detection of Enterovirus 71 by using nanogold-enhanced electrochemical impedance spectroscopy  

NASA Astrophysics Data System (ADS)

Enterovirus 71 (EV71) infection is an emerging infectious disease causing neurological complications and/or death within two to three days after the development of fever and rash. A low viral titre in clinical specimens makes the detection of EV71 difficult. Conventional approaches for detecting EV71 are time consuming, poorly sensitive, or complicated, and cannot be used effectively for clinical diagnosis. Furthermore, EV71 and Coxsackie virus A16 (CA16) may cross react in conventional assays. Therefore, a rapid, highly sensitive, specific, and user-friendly test is needed. We developed an EV71-specific nanogold-modified working electrode for electrochemical impedance spectroscopy in the detection of EV71. Our results show that EV71 can be distinguished from CA16, Herpes simplex virus, and lysozyme, with the modified nanogold electrode being able to detect EV71 in concentrations as low as 1 copy number/50 ?l reaction volume, and the duration between sample preparation and detection being 11 min. This detection platform may have the potential for use in point-of-care diagnostics.

Li, Hsing-Yuan; Tseng, Shing-Hua; Cheng, Tsai-Mu; Chu, Hsueh-Liang; Lu, Yu-Ning; Wang, Fang-Yu; Tsai, Li-Yun; Shieh, Juo-Yu; Yang, Jyh-Yuan; Juan, Chien-Chang; Tu, Lung-Chen; Chang, Chia-Ching

2013-07-01

288

Concentration of enteroviruses from large volumes of tap water, treated sewage, and seawater.  

PubMed Central

Methods are described for the efficient concentration of an enterovirus from large volumes of tap water, sewage, and seawater. Virus in acidified water (pH 3.5) in the presence of aluminum chloride was adsorbed to a 10-inch (ca. 25.4 cm) fiberglass depth cartridge and a 10-inch pleated epoxy-fiberglass filter in a series at flow rates of up to 37.8 liters (10 gallons) per min. Adsorbed viruses were eluted from the filters with glycine buffer (pH 10.5 to 11.5), and the eluate was reconcentrated by using a combination of aluminum flocculation followed by hydroextraction. With this procedure, poliovirus in large volumes of tap water, seawater, and sewage could be concentrated with an average efficiency of 52, 53, and 50%, respectively. It was demonstrated that this method is capable of detecting surface solid-associated viruses originating from sewage treatment plants. No difference in virus recovery between laboratory batch studies and a set-up with acid-salt injection was found. This unified scheme for the concentration of viruses has many advantages over previously described systems. These include: high operating flow rates, low weight and small size, effectiveness with a variety of waters with widely varying qualities, and filters with a high resistance to clogging. PMID:205175

Gerba, C P; Farrah, S R; Goyal, S M; Wallis, C; Melnick, J L

1978-01-01

289

Antiviral Ability of Kalanchoe gracilis Leaf Extract against Enterovirus 71 and Coxsackievirus A16.  

PubMed

Pandemic infection or reemergence of Enterovirus 71 (EV71) and coxsackievirus A16 (CVA16) occurs in tropical and subtropical regions, being associated with hand-foot-and-mouth disease, herpangina, aseptic meningitis, brain stem encephalitis, pulmonary edema, and paralysis. However, effective therapeutic drugs against EV71 and CVA16 are rare. Kalanchoe gracilis (L.) DC is used for the treatment of injuries, pain, and inflammation. This study investigated antiviral effects of K. gracilis leaf extract on EV71 and CVA16 replications. HPLC analysis with a C-18 reverse phase column showed fingerprint profiles of K. gracilis leaf extract had 15 chromatographic peaks. UV/vis absorption spectra revealed peaks 5, 12, and 15 as ferulic acid, quercetin, and kaempferol, respectively. K. gracilis leaf extract showed little cytotoxicity, but exhibited concentration-dependent antiviral activities including cytopathic effect, plaque, and virus yield reductions. K. gracilis leaf extract was shown to be more potent in antiviral activity than ferulic acid, quercetin, and kaempferol, significantly inhibiting in vitro replication of EV71 (IC(50) = 35.88??g/mL) and CVA16 (IC(50) = 42.91??g/mL). Moreover, K. gracilis leaf extract is a safe antienteroviral agent with the inactivation of viral 2A protease and reduction of IL-6 and RANTES expressions. PMID:22666293

Wang, Ching-Ying; Huang, Shun-Chueh; Zhang, Yongjun; Lai, Zhen-Rung; Kung, Szu-Hao; Chang, Yuan-Shiun; Lin, Cheng-Wen

2012-01-01

290

Enterovirus 71 infection and acute neurological disease among children in Brazil (1988-1990).  

PubMed

Surveillance for Enterovirus 71 (EV-71) infection in children up to 15 years of age was carried out in Brazil, from 1988 to 1990. Patients with acute neurological diseases (AND) such as flaccid paralysis, Bell's palsy, acute cerebellar ataxia and Guillain-Barré syndrome were included in the study. EV-71 infection was detected in 24 of 426 children (5.6%) with AND. EV-71 infection was confirmed only by virus isolation in 13 children, by virus isolation and seroconversion in 4, and by seroconversion alone in 7. EV-71 was also isolated from 15 of the 427 household contacts (3.5%) of 165 AND patients. There was some evidence of high infectivity of EV-71: household clusters were detected in the case of 7 of 24 children (29.1%) infected with EV-71 and manifesting AND; EV-71 was isolated from 11/40 household contacts (27.5%) of the infected patients but from only 4/387 household contacts (1.0%) of children in whom it was not possible to demonstrate EV-71 infection. Seven of the 24 children infected with EV-71 exhibited residual motor deficiency when examined 6 months after the disease onset. The relevance of these results for the Plan for Global Eradication of Wild Poliovirus is discussed, as well as the need to increase knowledge about the behaviour of this virus and its possible association with AND. PMID:9692141

Takimoto, S; Waldman, E A; Moreira, R C; Kok, F; Pinheiro, F de P; Saes, S G; Hatch, M; de Souza, D F; Carmona, R de C; Shout, D; de Moraes, J C; Costa, A M

1998-01-01

291

Identification of small interfering RNAs which inhibit the replication of several Enterovirus 71 strains in China.  

PubMed

Enterovirus 71 (EV 71) is one of the commonest causative agents of hand, foot, and mouth disease (HFMD), which infects mainly young children. It has been associated with severe neurological complications worldwide, and has caused significant deaths in many provinces of China from March to May 2008. In this study, RNA interference (RNAi) was used as an antiviral agent to inhibit EV 71 replication in rhabdomyosarcoma (RD) cells. Three small interfering RNAs (siRNAs) targeting extremely conserved regions among multiple EV 71 strains in China could effectively block the replication of EV 71 strain Shzh-98. Combination transfection of these three siRNAs could produce a strong inhibitory effect not only in strain Shzh-98, but also in one epidemic strain Fuyang-0805 isolated from a child in the city of Fuyang with a clinical diagnosis of HFMD in 2008. These strategies and results suggest that RNAi has potential therapeutic use for the suppression of EV 71 infection in a broad spectrum of viral strains. PMID:19490979

Wu, Zhiqiang; Yang, Fan; Zhao, Rong; Zhao, Lina; Guo, Deyin; Jin, Qi

2009-08-01

292

Altered cellular but not humoral reactions in children with complicated enterovirus 71 infections in Taiwan.  

PubMed

Enterovirus 71 (EV 71) infections have high neurovirulence and fatality. Immune responses were assessed in 78 patients with EV 71 infection. EV 71 meningoencephalitis occurred more frequently in younger children and in boys. C-reactive protein levels were not elevated, although total leukocyte counts were increased in these patients. The CD40-ligand expression on T cells significantly decreased in children with meningoencephalitis (P=.041). Polymorphism of the cytotoxic T lymphocyte antigen-4 (CTLA-4) at position 49 of exon 1 showed a higher frequency of G/G genotype in patients with EV 71 meningoencephalitis than in those without meningoencephalitis (18/31 vs. 14/47; P=.045) and in control subjects (18/31 vs. 25/93l; P=.007). Specific EV 71 neutralizing antibody titers were detectable but did not differ in children with and without meningoencephalitis in the acute and convalescent stages. Results from this study suggest that younger children with a certain CTLA-4 polymorphism and altered cellular but not humoral response may be linked to EV 71 meningoencephalitis. PMID:11237800

Yang, K D; Yang, M Y; Li, C C; Lin, S F; Chong, M C; Wang, C L; Chen, R F; Lin, T Y

2001-03-15

293

An eight-year study of epidemiologic features of enterovirus 71 infection in Taiwan.  

PubMed

In 1998, an epidemic of enterovirus 71 (EV 71) infection occurred in Taiwan. The purpose of this study was to assess the epidemiology of EV 71 infection in Taiwan. Between March 1998 and December 2005, a total of 1,548 severe cases of hand-foot-mouth disease and herpangina (HFMD/HA) was reported to the Center for Disease Control in Taiwan. A seasonal variation in number of severe cases was observed, with the annual peak in second quarter. Deaths from severe HFMD/HA varied from year to year (chi(2) for trend = 6.781, P = 0.009). Most (92%) cases occurred in children

Chen, Shou-Chien; Chang, Hsiao-Ling; Yan, Tsong-Rong; Cheng, Yan-Tzong; Chen, Kow-Tong

2007-07-01

294

Inhibition of Enterovirus 71 replication by 7-hydroxyflavone and diisopropyl-flavon7-yl Phosphate.  

PubMed

Enterovirus 71 (EV71) is the major causative agent of hand, foot, and mouth disease, which has been continuously prevalent in Asia in recent years. In children, severe cases can lead to death, and no prophylactic or therapeutic measures against EV71 infection are available. The 3C proteases of EV71 play an important role in viral replication and are an ideal drug target. In previous work, we resolved the crystal structure for EV71 3Cpro. In this report, we took advantage of the automated docking program AutoDock 4.0 to simulate EV71 3Cpro-ligand conformation. 7-hydroxyflavone (HF) and its phosphate ester(FIP) were predicted to bind with EV71 3Cpro.In an in vitro protease inhibition assay, FIP inhibited EV71 3Cpro protease activity. Both flavones were highly active against EV71, protecting cells from EV71 infection. Replication of viral RNA and formation of EV71 plaque were all strongly inhibited in cells. These results indicated that HF and FIP may serve as potential protective agents in the treatment of patients with chronic EV71 infection. PMID:24664133

Wang, Jianmin; Su, Haoxiang; Zhang, Ting; Du, Jiang; Cui, Sheng; Yang, Fan; Jin, Qi

2014-01-01

295

Antiviral Ability of Kalanchoe gracilis Leaf Extract against Enterovirus 71 and Coxsackievirus A16  

PubMed Central

Pandemic infection or reemergence of Enterovirus 71 (EV71) and coxsackievirus A16 (CVA16) occurs in tropical and subtropical regions, being associated with hand-foot-and-mouth disease, herpangina, aseptic meningitis, brain stem encephalitis, pulmonary edema, and paralysis. However, effective therapeutic drugs against EV71 and CVA16 are rare. Kalanchoe gracilis (L.) DC is used for the treatment of injuries, pain, and inflammation. This study investigated antiviral effects of K. gracilis leaf extract on EV71 and CVA16 replications. HPLC analysis with a C-18 reverse phase column showed fingerprint profiles of K. gracilis leaf extract had 15 chromatographic peaks. UV/vis absorption spectra revealed peaks 5, 12, and 15 as ferulic acid, quercetin, and kaempferol, respectively. K. gracilis leaf extract showed little cytotoxicity, but exhibited concentration-dependent antiviral activities including cytopathic effect, plaque, and virus yield reductions. K. gracilis leaf extract was shown to be more potent in antiviral activity than ferulic acid, quercetin, and kaempferol, significantly inhibiting in vitro replication of EV71 (IC50 = 35.88??g/mL) and CVA16 (IC50 = 42.91??g/mL). Moreover, K. gracilis leaf extract is a safe antienteroviral agent with the inactivation of viral 2A protease and reduction of IL-6 and RANTES expressions. PMID:22666293

Wang, Ching-Ying; Huang, Shun-Chueh; Zhang, Yongjun; Lai, Zhen-Rung; Kung, Szu-Hao; Chang, Yuan-Shiun; Lin, Cheng-Wen

2012-01-01

296

Enterovirus 71 Induces Mitochondrial Reactive Oxygen Species Generation That is Required for Efficient Replication  

PubMed Central

Redox homeostasis is an important host factor determining the outcome of infectious disease. Enterovirus 71 (EV71) infection has become an important endemic disease in Southeast Asia and China. We have previously shown that oxidative stress promotes viral replication, and progeny virus induces oxidative stress in host cells. The detailed mechanism for reactive oxygen species (ROS) generation in infected cells remains elusive. In the current study, we demonstrate that mitochondria were a major ROS source in EV71-infected cells. Mitochondria in productively infected cells underwent morphologic changes and exhibited functional anomalies, such as a decrease in mitochondrial electrochemical potential ??m and an increase in oligomycin-insensitive oxygen consumption. Respiratory control ratio of mitochondria from infected cells was significantly lower than that of normal cells. The total adenine nucleotide pool and ATP content of EV71-infected cells significantly diminished. However, there appeared to be a compensatory increase in mitochondrial mass. Treatment with mito-TEMPO reduced eIF2? phosphorylation and viral replication, suggesting that mitochondrial ROS act to promote viral replication. It is plausible that EV71 infection induces mitochondrial ROS generation, which is essential to viral replication, at the sacrifice of efficient energy production, and that infected cells up-regulate biogenesis of mitochondria to compensate for their functional defect. PMID:25401329

Cheng, Mei-Ling; Weng, Shiue-Fen; Kuo, Chih-Hao; Ho, Hung-Yao

2014-01-01

297

Characterization of the enterovirus 71 VP1 protein as a vaccine candidate.  

PubMed

Enterovirus 71 (EV71) is an important agent responsible for hand-foot-and-mouth disease (HFMD), which can cause severe neurological complications and death in children. However, there is no specific treatment for EV71 infection, and a safe and effective vaccine is needed urgently. In this study, an effective and economical method for the production of EV71-VP1 protein was developed, and the VP1 protein was evaluated in humoral and cellular immune responses as an EV71 vaccine. The results revealed that the VP1 protein induced high titers of cross-neutralizing antibodies for different EV71 subtypes, and elicited significant splenocyte proliferation. The high levels of IFN-r and IL-10 showed the VP1 protein induced a mixed Th1 and Th2 immune response. Vaccinated female mice could confer protection in their neonatal offspring. Compared with the inactivated EV71, the VP1 protein elicited similar humoral and cellular responses, but the engineered protein is safer, less expensive and can be produced more efficiently. Therefore, EV71-VP1 protein can induce effective immunologic protection against EV71 and is an ideal candidate against EV71 infection. J. Med. Virol. 87:256-262, 2015. © 2014 Wiley Periodicals, Inc. PMID:25043151

Zhou, Shi-Li; Ying, Xiao-Ling; Han, Xue; Sun, Xian-Xun; Jin, Qi; Yang, Fan

2015-02-01

298

Human genes involved in hepatitis B virus infection  

PubMed Central

Persistent hepatitis B virus (HBV) infection is a significant public health problem because it is a major cause of chronic liver disease, cirrhosis, and hepatocellular carcinoma (HCC). Roughly one-third of the world population has been infected with HBV and there are about 350 million (5%-6%) persistent carriers. HBV causes 80% of all liver cancer cases and is the second most important carcinogen, after smoking tobacco. There is an approximate 90% risk of becoming a persistent carrier following perinatal infection in infants born to e antigen positive carrier mothers and a 30% risk in pre-school children. Only 5%-10% of adults become persistent carriers following infection. Of individuals persistently infected with HBV, 10%-30% will develop liver cirrhosis and HCC. These highly variable outcomes in both clearance rates and disease outcomes in persistently infected individuals cannot be fully explained by differences in immunological, viral or environmental factors. Thus, differences in host genetic factors may affect the natural history of hepatitis B. PMID:24976707

Zeng, Zheng

2014-01-01

299

Identification of STAT5A and STAT5B target genes in human T cells.  

PubMed

Signal transducer and activator of transcription (STAT) comprises a family of universal transcription factors that help cells sense and respond to environmental signals. STAT5 refers to two highly related proteins, STAT5A and STAT5B, with critical function: their complete deficiency is lethal in mice; in humans, STAT5B deficiency alone leads to endocrine and immunological problems, while STAT5A deficiency has not been reported. STAT5A and STAT5B show peptide sequence similarities greater than 90%, but subtle structural differences suggest possible non-redundant roles in gene regulation. However, these roles remain unclear in humans. We applied chromatin immunoprecipitation followed by DNA sequencing using human CD4(+) T cells to detect candidate genes regulated by STAT5A and/or STAT5B, and quantitative-PCR in STAT5A or STAT5B knock-down (KD) human CD4(+) T cells to validate the findings. Our data show STAT5A and STAT5B play redundant roles in cell proliferation and apoptosis via SGK1 interaction. Interestingly, we found a novel, unique role for STAT5A in binding to genes involved in neural development and function (NDRG1, DNAJC6, and SSH2), while STAT5B appears to play a distinct role in T cell development and function via DOCK8, SNX9, FOXP3 and IL2RA binding. Our results also suggest that one or more co-activators for STAT5A and/or STAT5B may play important roles in establishing different binding abilities and gene regulation behaviors. The new identification of these genes regulated by STAT5A and/or STAT5B has major implications for understanding the pathophysiology of cancer progression, neural disorders, and immune abnormalities. PMID:24497979

Kanai, Takahiro; Seki, Scott; Jenks, Jennifer A; Kohli, Arunima; Kawli, Trupti; Martin, Dorrelyn Patacsil; Snyder, Michael; Bacchetta, Rosa; Nadeau, Kari C

2014-01-01

300

Identification of STAT5A and STAT5B Target Genes in Human T Cells  

PubMed Central

Signal transducer and activator of transcription (STAT) comprises a family of universal transcription factors that help cells sense and respond to environmental signals. STAT5 refers to two highly related proteins, STAT5A and STAT5B, with critical function: their complete deficiency is lethal in mice; in humans, STAT5B deficiency alone leads to endocrine and immunological problems, while STAT5A deficiency has not been reported. STAT5A and STAT5B show peptide sequence similarities greater than 90%, but subtle structural differences suggest possible non-redundant roles in gene regulation. However, these roles remain unclear in humans. We applied chromatin immunoprecipitation followed by DNA sequencing using human CD4+ T cells to detect candidate genes regulated by STAT5A and/or STAT5B, and quantitative-PCR in STAT5A or STAT5B knock-down (KD) human CD4+ T cells to validate the findings. Our data show STAT5A and STAT5B play redundant roles in cell proliferation and apoptosis via SGK1 interaction. Interestingly, we found a novel, unique role for STAT5A in binding to genes involved in neural development and function (NDRG1, DNAJC6, and SSH2), while STAT5B appears to play a distinct role in T cell development and function via DOCK8, SNX9, FOXP3 and IL2RA binding. Our results also suggest that one or more co-activators for STAT5A and/or STAT5B may play important roles in establishing different binding abilities and gene regulation behaviors. The new identification of these genes regulated by STAT5A and/or STAT5B has major implications for understanding the pathophysiology of cancer progression, neural disorders, and immune abnormalities. PMID:24497979

Kanai, Takahiro; Seki, Scott; Jenks, Jennifer A.; Kohli, Arunima; Kawli, Trupti; Martin, Dorrelyn Patacsil; Snyder, Michael; Bacchetta, Rosa; Nadeau, Kari C.

2014-01-01

301

The role of microRNA-26b in human adipocyte differentiation and proliferation.  

PubMed

Recent findings indicate that microRNAs (miRNAs) are involved in the regulatory network of adipogenesis and obesity. Thus far, only a few human miRNAs are known to function as adipogenic regulators, fanning interest in studies on the functional role of miRNAs during adipogenesis in humans. In a previous study, we used a microarray to assess miRNA expression during human preadipocyte differentiation. We found that expression of the miR-26b was increased in mature adipocytes. MiR-26b is an intronic miRNA located in the intron of CTDSP1 (carboxy terminal domain, RNA polymerase II, polypeptide A, small phosphatase 1). Target prediction and Renilla luciferase analyses revealed the phosphatase and tensin homolog gene (PTEN) as a putative target gene. In this study, we found that miR-26b was gradually upregulated during adipocyte differentiation. To understand the roles of miR-26b in adipogenesis, we adopted a loss-of-function approach to silence miR-26b stably in human preadipocytes. We found that miR-26b inhibition effectively suppressed adipocyte differentiation, as evidenced by decreased lipid droplets and the ability of miR-26b to decrease mRNA levels of adipocyte-specific molecular markers and triglyceride accumulation. Furthermore, the cell growth assay revealed that miR-26b inhibition promoted proliferation. Nevertheless, it had no effect on apoptosis. Taken together, these data indicate that miR-26b may be involved in adipogenesis and could be targeted for therapeutic intervention in obesity. PMID:24140453

Song, Guixian; Xu, Guangfeng; Ji, Chenbo; Shi, Chunmei; Shen, Yahui; Chen, Ling; Zhu, Lijun; Yang, Lei; Zhao, Yaping; Guo, Xirong

2014-01-10

302

Detection of antibody to group B adult diarrhea rotaviruses in humans.  

PubMed Central

Group B rotaviruses have been responsible for annual epidemics of severe diarrhea affecting both adults and children in China. We developed a specific and sensitive enzyme-linked immunosorbent blocking assay to detect antibody to group B rotaviruses that will be useful to assess the role of group B rotavirus infections as a cause of human gastroenteritis. We tested 219 human sera and 18 immunoglobulin pools collected from eight countries for antibodies to both group A and group B rotaviruses. Overall, a low proportion (10 of 237 or 4.2%) of sera contained antibody to group B rotaviruses. Antibody to group B rotavirus was detected in only 1 of 155 serum samples from healthy or hospitalized individuals in the United States, including patients with the chronic inflammatory bowel diseases Crohn's disease and ulcerative colitis. No antibody was detected in 15 serum samples from Australia and from an outbreak of gastroenteritis on a cruise ship or in nine immunoglobulin pools from Japan and the United Kingdom. Antibody to group B rotaviruses was detected in 8 convalescent-(but not acute-)phase serum samples from Chinese patients with group B gastroenteritis, in five immunoglobulin pools from China, in 1 of 6 serum samples from Chinese students in the United States, and in 1 each of 10 serum samples from Kenya, 20 from Thailand, and 15 from Canada. In contrast, most of these samples (226 of 237 or 95.4%) had antibody to group A rotaviruses. These results indicate that human infection with group B rotavirus has not been widespread in areas outside China. Seroconversion observed between the acute-and convalescent-phase serum samples from China also suggests that infections with this virus are primary infections. Continued surveillance for this new group of rotaviruses should determine whether the many susceptible people become infected of whether other factors influence the severe pathogenicity of human infections with these viruses in China. PMID:3034964

Nakata, S; Estes, M K; Graham, D Y; Wang, S S; Gary, G W; Melnick, J L

1987-01-01

303

Effect of increased HoxB4 on human megakaryocytic development  

SciTech Connect

Research highlights: {yields} HoxB4 overexpression in human TF1 cells increased the expression of CD61 and CD41a. {yields} HoxB4 fusion protein enhanced megakaryocytic development of CD34{sup +} cord blood cells. {yields} Ectopic HoxB4 increased Tpo receptor expression and decreased c-Myb expression. {yields} HoxB4 RNA silencing increased c-Myb expression and decreased Fli-1 expression. -- Abstract: In order to produce clinically useful quantities of platelets ex vivo we may need to firstly enhance early self-renewal of hematopoietic stem cells (HSCs) and/or megakaryocyte (Mk) progenitors. The homeodomain transcription factor HoxB4 has been shown to be an important regulator of stem cell renewal and hematopoiesis; however, its effect on megakaryopoiesis is unclear. In this study, we investigated the effect of HoxB4 overexpression or RNA silencing on megakaryocytic development in the human TF1 progenitor cell line; we then used recombinant tPTD-HoxB4 fusion protein to study the effect of exogenous HoxB4 on megakaryocytic development of human CD34 positively-selected cord blood cells. We found that ectopic HoxB4 in TF1 cells increased the antigen expression of CD61and CD41a, increased the gene expression of thrombopoietin receptor (TpoR), Scl-1, Cyclin D1, Fog-1 and Fli-1 while it decreased c-Myb expression. HoxB4 RNA silencing in TF1 cells decreased the expression of CD61 and CD41a and decreased Fli-1 expression while it increased the expression of c-Myb. Recombinant tPTD-HoxB4 fusion protein increased the percentages and absolute numbers of CD41a and CD61 positive cells during megakaryocytic differentiation of CD34 positively-selected cord blood cells and increased the numbers of colony-forming unit-megakaryocyte (CFU-Mk). Adding tPTD-HoxB4 fusion protein increased the gene expression of TpoR, Cyclin D1, Fog-1 and Fli-1 while it inhibited c-Myb expression. Our data suggest that increased HoxB4 enhanced early megakaryocytic development in human TF1 cells and CD34 positively-selected cord blood cells primarily by upregulating TpoR and Fli-1 expression and downregulating c-Myb expression. Increasing HoxB4 expression or adding recombinant HoxB4 protein might be a way to expand Mks for the production of platelets for use in transfusion medicine.

Zhong, Yiming [Department of Pathology, The Ohio State University, Columbus, OH (United States) [Department of Pathology, The Ohio State University, Columbus, OH (United States); Program in Molecular, Cellular, and Developmental Biology, The Ohio State University, Columbus, OH (United States); Sullenbarger, Brent [Department of Pathology, The Ohio State University, Columbus, OH (United States)] [Department of Pathology, The Ohio State University, Columbus, OH (United States); Lasky, Larry C., E-mail: Lasky.4@osu.edu [Department of Pathology, The Ohio State University, Columbus, OH (United States); Program in Molecular, Cellular, and Developmental Biology, The Ohio State University, Columbus, OH (United States)

2010-07-30

304

Impaired T cell activation and cytokine production by calcitriol-primed human B cells.  

PubMed

The biologically active form of vitamin D3 , 1, 25-dihydroxyvitamin D3 (calcitriol), is a potent modulator of the immune response. We have shown previously that calcitriol modulates the immunoglobulin response in vitro and in vivo in mice and humans. To analyse the underlying molecular mechanisms we studied whether calcitriol-primed B cells modulate T cell activation and function. Human B cells were stimulated with anti-CD40 and interleukin (IL)-4 in the presence of increasing concentrations of calcitriol. After removal of calcitriol, primed B cells were co-cultured with autologous CD4(+) T cells; the B cell phenotype T cell activation and their consecutive cytokine production were also assessed. Naive T cells co-cultured with calcitriol-primed naive B cells showed a reduced expansion, nuclear factor of activated T cells, cytoplasmic 2 (NFATc2) expression and cytokine production upon restimulation. CD86 expression on B cells after calcitriol priming was identified as an underlying mechanism, as T cell activation and expansion was rescued by activating anti-CD28 antibodies. Our data indicate that calcitriol-primed B cells display an impaired capacity to activate T cells. Taken together, we identified a novel B cell-dependent vitamin D immune regulatory mechanism, namely by decreased co-stimulation of calcitriol-primed B cells. PMID:24965738

Drozdenko, G; Scheel, T; Heine, G; Baumgrass, R; Worm, M

2014-11-01

305

Imaging of nuclear factor ?B activation induced by ionizing radiation in human embryonic kidney (HEK) cells.  

PubMed

Ionizing radiation modulates several signaling pathways resulting in transcription factor activation. Nuclear factor kappa B (NF-?B) is one of the most important transcription factors that respond to changes in the environment of a mammalian cell. NF-?B plays a key role not only in inflammation and immune regulation but also in cellular radiation response. In response to DNA damage, NF-?B might inhibit apoptosis and promote carcinogenesis. Our previous studies showed that ionizing radiation is very effective in inducing biological damages. Therefore, it is important to understand the radiation-induced NF-?B signaling cascade. The current study aims to improve existing mammalian cell-based reporter assays for NF-?B activation by the use of DD-tdTomato which is a destabilized variant of red fluorescent protein tdTomato. It is demonstrated that exposure of recombinant human embryonic kidney cells (HEK/293 transfected with a reporter constructs containing NF-?B binding sites in its promoter) to ionizing radiation induces NF-?B-dependent DD-tdTomato expression. Using this reporter assays, NF-?B signaling in mammalian cells was monitored by flow cytometry and fluorescence microscopy. Activation of NF-?B by the canonical pathway was found to be quicker than by the genotoxin- and stress-induced pathway. X-rays activate NF-?B in HEK cells in a dose-dependent manner, and the extent of NF-?B activation is higher as compared to camptothecin. PMID:24880906

Chishti, Arif Ali; Baumstark-Khan, Christa; Hellweg, Christine E; Reitz, Günther

2014-08-01

306

Murine and human b locus pigmentation genes encode a glycoprotein (gp75) with catalase activity  

SciTech Connect

Melanogenesis is regulated in large part by tyrosinase, and defective tyrosinase leads to albinism. The mechanisms for other pigmentation determinants (e.g., those operative in tyrosinase-positive albinism and in murine coat-color mutants) are not yet known. One murine pigmentation gene, the brown (b) locus, when mutated leads to a brown (b/b) or hypopigmentated (B{sup lt}/B{sup lt}) coat versus the wild-type black (B/B). The authors show that the b locus codes for a glycoprotein with the activity of a catalase (catalase B). Only the c locus protein is a tyrosinase. Because peroxides may be by-products of melanogenic activity and hydrogen peroxide in particular is known to destroy melanin precursors and melanin, they conclude that pigmentation is controlled not only by tyrosinase but also by a hydroperoxidase. The studies indicate that catalase B is identical with gp75, a known human melanosomal glycoprotein; that the b mutation is in a heme-associated domain; and that the B{sup lt} mutation renders the protein susceptible to rapid proteolytic degradation.

Halaban, R.; Moellmann, G. (Yale Univ. School of Medicine, New Haven, CT (USA))

1990-06-01

307

Control of the Human B-Globin Gene  

NSDL National Science Digital Library

The diagram shows some of the gene regulatory proteins thought to control expression of this gene during red blood cell development. Some of the gene regulatory proteins shown, such as CP1, are found in many types of cells, while others, such as GATA-1, are present in only a few types of cells, including red blood cell precursors, and are therefore thought to contribute to the cell-type specificity of beta-globin gene expression. As indicated by the bidirectional arrows, several of the binding sites for GATA-1 overlap those of other gene regulatory proteins; it is thought that occupancy of these sites by GATA-1 excludes binding of other proteins. (Adapted from B. Emerson, In Gene Expression: General and Cell-Type Specific (M. Karin, ed.), pp. 116-161. Boston: Birkhauser, 1993.)

Bruce Alberts

1998-07-01

308

Oxytocin activates NF-?B-mediated inflammatory pathways in human gestational tissues.  

PubMed

Human labour, both at term and preterm, is preceded by NF-?B-mediated inflammatory activation within the uterus, leading to myometrial activation, fetal membrane remodelling and cervical ripening. The stimuli triggering inflammatory activation in normal human parturition are not fully understood. We show that the neurohypophyseal peptide, oxytocin (OT), activates NF-?B and stimulates downstream inflammatory pathways in human gestational tissues. OT stimulation (1?pM-100?nM) specifically via its receptor (OTR) in human myometrial and amnion primary cells led to MAPK and NF-?B activation within 15?min and maximal p65-subunit nuclear translocation within 30?min. Both in human myometrium and amnion, OT-induced activation of the canonical NF-?B pathway upregulated key inflammatory labour-associated genes including IL-8, CCL5, IL-6 and COX-2. IKK? inhibition (TPCA1; 10?µM) suppressed OT-induced NF-?B-p65 phosphorylation, whereas p65-siRNA knockdown reduced basal and OT-induced COX-2 levels in myometrium and amnion. In both gestational tissues, MEK1/2 (U0126; 10?µM) or p38 inhibition (SB203580; 10?µM) suppressed OT-induced COX-2 expression, but OT-induced p65-phosphorylation was only inhibited in amnion, suggesting OT activation of NF-?B in amnion is MAPK-dependent. Our data provide new insight into the OT/OTR system in human parturition and suggest that its therapeutic modulation could be a strategy for regulating both contractile and inflammatory pathways in the clinical context of term/preterm labour. PMID:25451977

Kim, Sung Hye; MacIntyre, David A; Da Silva, Maria Firmino; Blanks, Andrew M; Lee, Yun S; Thornton, Steven; Bennett, Phillip R; Terzidou, Vasso

2014-11-14

309

Chromosomal localisation of the human homologues to the oncogenes erbA and B.  

PubMed Central

Avian erythroblastosis virus (AEV) induces acute erythroleukemia and sarcomas in vivo and it transforms erythroblasts and fibroblasts in vitro. The virus has two host cell-derived genes, v-erbA and v-erbB. The latter encodes the oncogenic capacity of the virus, whereas v-erbA enhances the erythroblast transforming effects of v-erbB while being unable to induce neoplasms independently. Recently, human cellular homologues of these viral erb genes have been isolated. The chromosomal locations of two of these genes have been determined using EcoRI-digested DNA prepared from human-mouse somatic cell hybrids. The human c-erbA1 gene has been assigned to chromosome 17 and is located between 17p11 and 17q21. The human c-erbB sequence has been assigned to chromosome 7 and is located between 7pter and 7q22. Thus, in the human genome these genes are on two separate chromosomes. No evidence for the involvement of the human c-erb genes in neoplasia has been found. Images Fig. 1. PMID:6323162

Spurr, N K; Solomon, E; Jansson, M; Sheer, D; Goodfellow, P N; Bodmer, W F; Vennstrom, B

1984-01-01

310

Genetic inactivation of TRAF3 in canine and human B-cell lymphoma.  

PubMed

Non-Hodgkin lymphomas (NHLs) are the most common cancer to affect pet dogs. In contrast to the many genes whose mutation contributes to lymphomagenesis in humans, relatively little is known about the acquired genetic alterations that lead to canine B-cell lymphomas (cBCLs). We performed a survey of 84 canine NHL tumors to identify genes affected by somatic point mutations. We found mutations affecting TRAF3, which encodes a negative regulator of nuclear factor (NF)-?B, to be a common feature of cBCLs, with mutations observed in 44% of tumors including a combination of somatic and rare germ-line variants. Overall, 30% of the tumors contained ?1 somatic TRAF3 mutation. The majority of mutations are predicted to cause loss of TRAF3 protein including those impacting reading frame and splicing. To determine whether TRAF3 loss might be relevant to human NHL, we also analyzed 148 human diffuse large B-cell lymphoma (DLBCL) tumors and identified loss of TRAF3 as a common event, affecting ?9% of DLBCLs, and reduced expression of TRAF3 among deleted cases. This study implicates mutations affecting NF-?B activity as a novel genetic commonality between human and canine NHLs and supports the potential utility of cBCLs with mutated TRAF3 as a model of the more aggressive activated B-cell subgroup of DLBCL. PMID:25468570

Bushell, Kevin R; Kim, Yukyoung; Chan, Fong Chun; Ben-Neriah, Susana; Jenks, Andrew; Alcaide, Miguel; Fornika, Daniel; Grande, Bruno M; Arthur, Sarah; Gascoyne, Randy D; Steidl, Christian; Morin, Ryan D

2015-02-01

311

Fast and high-affinity binding of B-lymphotropic papovavirus to human B-lymphoma cell lines.  

PubMed Central

Binding of B-lymphotropic papovavirus (LPV) to host cells differing in susceptibility to viral infection was determined by a newly established, direct, nonradioactive virus binding assay, which allows quantitative description of the binding characteristics by receptor saturation and Scatchard analysis. LPV binding to the highly susceptible human B-lymphoma cell line BJA-B K88 is specific, saturable, and noncooperative. Binding occurs very fast, with an association rate constant (k1) of 6.7 x 10(7) M-1s-1, and is of high affinity, with a dissociation constant (Kd) of 2.9 x 10(-12) M; and the virus-receptor complex is stable, with a half life of 70 min. The binding affinities of receptors on four other highly, moderately, or weakly susceptible human B-lymphoma cell lines were similar, with up to twofold variation around a mean Kd value of 3 x 10(-12) M, suggesting the presence of the same LPV receptor on all of these cell lines. This view is further supported by the finding that in all cases a terminal sialic acid is necessary for LPV binding. Tunicamycin has been shown to drastically induce LPV susceptibility and LPV binding in weakly and moderately susceptible B-lymphoma cell lines (O.T. Keppler, M. Herrmann, M. Oppenländer, W. Meschede, and M. Pawlita, J. Virol. 68:6933-6939, 1994). The hypothesis that the constitutively expressed and tunicamycin-induced LPV receptors are identical is strengthened by our finding that both receptor types displayed the same high affinity. LPV susceptibility of different B-lymphoma cell lines was correlated with receptor number but not with receptor affinity. The numbers of receptors per cell on highly and moderately susceptible cell lines ranged from 2,000 to 400 and were directly proportional to LPV susceptibility. This indicates that the number of high-affinity receptors per cell is a key regulating factor for the LPV host range. PMID:7474091

Herrmann, M; Oppenländer, M; Pawlita, M

1995-01-01

312

Mechanical properties of the human achilles tendon Tishya A.L. Wren a,b,*, Scott A. Yerby a,b  

E-print Network

Mechanical properties of the human achilles tendon Tishya A.L. Wren a,b,*, Scott A. Yerby a October 2000 Abstract Objective. To determine whether the human Achilles tendon has higher material testing of excised tendons. Background. While the human Achilles tendon appears to experience higher

Stanford University

313

Glucosamine inhibits IL1?-induced NF?B activation in human osteoarthritic chondrocytes  

Microsoft Academic Search

Objective: Glucosamine sulfate (GS) is a commonly used drug for the treatment of osteoarthritis. The mechanism of the action of this drug does, however, remain to be elucidated. In human osteoarthritic chondrocytes (HOC) stimulated with a proinflammatory cytokine, we studied whether GS could modify the NF?B activity and the expression of COX-2, a NF?B-dependent gene.Methods: Using HOC in culture stimulated

R Largo; M. A Alvarez-Soria; I D??ez-Ortego; E Calvo; O Sánchez-Pernaute; J Egido; G Herrero-Beaumont

2003-01-01

314

Kinin B2 Receptor-Coupled Signal Transduction in Human Cultured Keratinocytes  

Microsoft Academic Search

Kinins are key pro-inflammatory peptides that exhibit mitogenic effects in tissue-specific cellular systems. Since the life span of the keratinocyte is regulated by receptors that control proliferation and differentiation, and since both processes are affected during wound healing, we have examined the consequence of kinin B2 receptors (B2R) activation in cultured human keratinocytes. Stimulation of keratinocytes by Lys-bradykinin (LBK) induced

Maria A. Vidal; Angel Astroza; Carola E. Matus; Pamela Ehrenfeld; Francisca Pavicic; Tamara Sanchez; Christian Salem; Jaime Figueroa; Miguel Concha; Carlos B. Gonzalez; Carlos D. Figueroa

2005-01-01

315

Evaluation of liver fluke recombinant cathepsin B1 protease as a serodiagnostic antigen for human opisthorchiasis  

Microsoft Academic Search

A cathepsin B-like cysteine protease belonging to family C1 is abundantly expressed in the transcriptome and proteome of the carcinogenic liver fluke of humans, Opisthorchis viverrini. This enzyme is present in excretory\\/secretory (ES) products released by parasites cultured in vitro. This study evaluated the performance of recombinant O. viverrini cathepsin B1 (rOv-CB-1) as an antigen for immunodiagnosis of opisthorchiasis. The

Jittiyawadee Sripa; Paul J. Brindley; Banchob Sripa; Alex Loukas; Sasithorn Kaewkes; Thewarach Laha

316

Modulation of resistance to cisplatin by amphotericin B and aphidicolin in human larynx carcinoma cells  

Microsoft Academic Search

The aim of this study was to examine whether resistance to cisplatin [cis-diamminedichloroplatinum (II)] (CDDP) could be overcome by amphotericin B, cyclosporin A and aphidicolin in two sublines of human larynx carcinoma HEp2 cells. The sensitivity of parental and cisplatin-resistant CA3 and CK2 cells to amphotericin B, cyclosporin A and aphidicolin, and also the effects of these drugs (given in

Lidija Beketic-Oreskovic; Maja Osmak

1995-01-01

317

Modulation of resistance to cisplatin by amphotericin B and aphidicolin in human larynx carcinoma cells  

Microsoft Academic Search

The aim of this study was to examine whether resistance to cisplatin [ cis-diamminedichloroplatinum (II)] (CDDP) could be overcome by amphotericin B, cyclosporin A and aphidicolin in two sublines of human larynx carcinoma HEp2 cells. The sensitivity of parental and cisplatin-resistant CA3 and CK2 cells to amphotericin B, cyclosporin A and aphidicolin, and also the effects of these drugs (given

L. Beketic-Oreskovic; Maja Osmak

1995-01-01

318

Haploinsufficiency of RAD51B Causes Centrosome Fragmentation and Aneuploidy in Human Cells  

Microsoft Academic Search

The Rad51-like proteins, Rad51B, Rad51C, Rad51D, XRCC2, and XRCC3, have been shown to form two distinct complexes and seem to assist Rad51 in the early stages of homologous recombination. Although these proteins share sequence similarity with Rad51, they do not show functional redundancy. Among them, Rad51B is unique in that the gene maps to the human chromosome 14q23-24, the region

Osamu Date; Mari Ishida; Takashi Yoshihara; Aiko Kinomura; Taijiro Sued; Kiyoshi Miyagawa

2006-01-01

319

HIV1 Vpr regulates expression of b chemokines in human primary lymphocytes and macrophages  

Microsoft Academic Search

The HIV-1 vpr gene encodes a 14-kDa virion-packaged protein that has been implicated in viral pathogenesis. Vpr exhibits profound effects on human primary cells influencing proliferation, differentiation, apoptosis, and cytokine produc- tion, in part through NF-kB-mediated transcrip- tion. NF-kB, a potent transcription factor, acti- vates many proinflammatory cytokines\\/chemo- kines upon infection. Here, we analyzed the effect of extracellular Vpr as

Karuppiah Muthumani; Sagar Kudchodkar; Emmanouil Papasavvas; Luis J. Montaner; David B. Weiner; Velpandi Ayyavoo

2000-01-01

320

Sensitivity of human immunodeficiency virus infection to various a, b and c chemokines  

Microsoft Academic Search

Examination of a large panel of chemokines indi- cates that in addition to RANTES, MIP-1a and MIP- 1b, the b-chemokine MCP-2 and, to a lesser extent, the c-chemokine lymphotactin also show anti- human immunodeficiency virus (HIV) activity in cell culture. The amount of chemokine needed to sup- press HIV replication by Z 50% was generally greater (Z 250 ng\\/ml) than

Giampaolo Greco; Carl Mackewicz; Jay A. Levy

321

The human cytochrome b561 gene (CYB561) is located at 17q11-qter  

SciTech Connect

Cytochrome b561 is a major transmembrane protein that is specific to catacholamine and neuropeptide secretory vesicles of the adrenal medulla, pituitary gland, and other neuroendocrine tissues. This 30-kDa cytochrome is present in both the small synaptic vesicles and the large dense core vesicles (chromaffin granules) of the tissues. In this paper, we report that the human gene encoding cytochrome b561 (CYB561; GenBank Accession No. U06715) is localized to 17q11-qter.

McBride, O.W.; Yi, H.F.; Srivastava, M. [National Institutes of Health, Bethesda, MD (United States)] [National Institutes of Health, Bethesda, MD (United States)

1994-06-01

322

Do Humans Really Learn A[superscript n] B[superscript n] Artificial Grammars from Exemplars?  

ERIC Educational Resources Information Center

An important topic in the evolution of language is the kinds of grammars that can be computed by humans and other animals. Fitch and Hauser (F&H; 2004) approached this question by assessing the ability of different species to learn 2 grammars, (AB)[superscript n] and A[superscript n] B[superscript n]. A[superscript n] B[superscript n] was taken to…

Hochmann, Jean-Remy; Azadpour, Mahan; Mehler, Jacques

2008-01-01

323

Complement receptor 2/CD21? human naive B cells contain mostly autoreactive unresponsive clones  

PubMed Central

Complement receptor 2–negative (CR2/CD21?) B cells have been found enriched in patients with autoimmune diseases and in common variable immunodeficiency (CVID) patients who are prone to autoimmunity. However, the physiology of CD21?/lo B cells remains poorly characterized. We found that some rheumatoid arthritis (RA) patients also display an increased frequency of CD21?/lo B cells in their blood. A majority of CD21?/lo B cells from RA and CVID patients expressed germline autoreactive antibodies, which recognized nuclear and cytoplasmic structures. In addition, these B cells were unable to induce calcium flux, become activated, or proliferate in response to B-cell receptor and/or CD40 triggering, suggesting that these autoreactive B cells may be anergic. Moreover, gene array analyses of CD21?/lo B cells revealed molecules specifically expressed in these B cells and that are likely to induce their unresponsive stage. Thus, CD21?/lo B cells contain mostly autoreactive unresponsive clones, which express a specific set of molecules that may represent new biomarkers to identify anergic B cells in humans. PMID:20231422

Isnardi, Isabelle; Ng, Yen-Shing; Menard, Laurence; Meyers, Greta; Saadoun, David; Srdanovic, Iva; Samuels, Jonathan; Berman, Jessica; Buckner, Jane H.; Cunningham-Rundles, Charlotte

2010-01-01

324

Liposomal amphotericin B as a treatment for human leishmaniasis  

PubMed Central

Introduction: Leishmaniasis is a parasitic disease transmitted by phlebotomine sandflies. Between 700,000 and 1.2 million cases of cutaneous leishmaniasis and between 200,000 and 400,000 cases of visceral leishmaniasis (VL), which is fatal if left untreated, occur annually worldwide. Liposomal amphotericin B (LAMB), alone or in combination with other drugs, has been extensively studied as VL treatment, but data on routine field use are limited, and several challenges to patients' access to this life-saving drug remain. Areas covered: This article provides a review of clinical studies on LAMB for VL and other forms of leishmaniasis. The current development of generic versions of LAMB and related challenges are also discussed. Expert opinion: LAMB proved to be highly efficacious and safe in over 8000 VL patients treated by MÉdecins Sans Frontières in South Asia, and its use was feasible even at primary healthcare level. Despite requiring higher doses, LAMB is the drug of choice to treat vulnerable groups (e.g., pregnant or HIV positive) and relapsing VL patients in East Africa. LAMB should be included in national VL guidelines and registered in all VL endemic countries. Its cost should be further reduced and regulatory pathways to prove bioequivalence for generic LAMB products should be implemented. PMID:23167833

Balasegaram, Manica; Ritmeijer, Koert; Lima, Maria Angeles; Burza, Sakib; Ortiz Genovese, Gemma; Milani, Barbara; Gaspani, Sara; Potet, Julien; Chappuis, François

2012-01-01

325

Energetic and Molecular Water Permeation Mechanisms of the Human Red Blood Cell Urea Transporter B  

PubMed Central

Urea transporter B (UT-B) is a passive membrane channel that facilitates highly efficient permeation of urea. In red blood cells (RBC), while the major function of UT-B is to transport urea, it is assumed that this protein is able to conduct water. Here, we have revisited this last issue by studying RBCs and ghosts from human variants with defects of aquaporin 1 (AQP1) or UT-B. We found that UT-B's osmotic water unit permeability (pfunit) is similar to that of AQP1. The determination of diffusional permeability coefficient (Pd) allowed the calculation of the Pf/Pd ratio, which is consistent with a single-file water transport. Molecular dynamic simulations of water conduction through human UT-B confirmed the experimental finding. From these results, we propose an atomistic description of water–protein interactions involved in this permeation. Inside the UT-B pore, five water molecules were found to form a single-file and move rapidly along a channel by hydrogen bond exchange involving two critical threonines. We further show that the energy barrier for water located in the central region coincides with a water dipole reorientation, which can be related to the proton exclusion observed experimentally. In conclusion, our results indicate that UT-B should be considered as a new member of the water channel family. PMID:24376529

Azouzi, Slim; Gueroult, Marc; Ripoche, Pierre; Genetet, Sandrine; Colin Aronovicz, Yves; Le Van Kim, Caroline; Etchebest, Catherine; Mouro-Chanteloup, Isabelle

2013-01-01

326

Molecular cloning of a human small intestinal apolipoprotein B mRNA editing protein.  

PubMed

Mammalian small intestinal apolipoprotein B (apo B) mRNA undergoes posttranscriptional cytidine deamination with the production of an in frame stop codon and the translation of apo B48. We have isolated a cDNA from human jejunum which mediates in vitro editing of a synthetic apo B RNA template upon complementation with chicken intestinal S100 extracts. The cDNA specifies a 236 residue protein which is 69% identical to the apo B mRNA editing protein (REPR) cloned from rat small intestine [Teng, B., Burant, C. F. and Davidson, N. O. (1993) Science 260, 1816-1819] and which, by analogy, is referred to as HEPR. HEPR does not contain the carboxyl-terminus leucine zipper motif identified in REPR but contains consensus phosphorylation sites as well as the conserved histidine and both cysteine residues identified as a Zn2+ binding motif in other cytidine deaminases. The distribution of HEPR mRNA was predominantly confined to the adult small intestine with lower levels detectable by reverse-transcription polymerase chain reaction amplification in the stomach, colon and testis. These differences in the structure and distribution of the human as compared to the rat apo B mRNA editing protein suggest an important evolutionary adaptation in the mechanisms restricting apo B48 production to the small intestine. PMID:8208612

Hadjiagapiou, C; Giannoni, F; Funahashi, T; Skarosi, S F; Davidson, N O

1994-05-25

327

Development of a shaker culture of Buffalo green monkey kidney cells: potential use for detection of enteroviruses.  

PubMed Central

Buffalo green monkey kidney cells were adapted to grow as shaker cultures. Replication of environmental and clinical isolates of poliovirus, coxsackievirus, and echovirus in these cultures was analyzed by plaque assay and compared with replication in Buffalo green monkey kidney cell monolayers and HEp-2 cell shaker cultures. Dose-response tests with various concentrations of Mahoney type 1 poliovirus indicated that Buffalo green monkey kidney cell shaker cultures could detect as little as 1 PFU in an inoculum of 0.2 ml. These data suggest that Buffalo green monkey kidney cell shaker cultures can be effectively used for the detection of small quantities of enteroviruses from environmental sources. PMID:6289745

Goldstein, G; Guskey, L E

1982-01-01

328

Corruption of Human Follicular B-Lymphocyte Trafficking by a B-Cell Superantigen  

PubMed Central

Protein A (SpA) of Staphylococcus aureus is known to target the paratope of immunoglobulins expressing VH3 genes, and to delete marginal zone B cells and B-1a in vivo. We have discovered that SpA endows S. aureus with the potential to subvert B-cell trafficking in the host. We found that SpA, whose Fc-binding site has been inactivated, binds essentially to naïve B cells and induces a long-lasting decrease in CXCR4 expression and in B-cell chemotaxis to CXCL12. Competition experiments indicated that SpA does not interfere with binding of CXCR4 ligands and does not directly bind to CXCR4. This conclusion is strongly supported by the inability of SpA to modulate clathrin-mediated CXCR4 internalization, which contrasts with the potent effect of anti-immunoglobin M (IgM) antibodies. Microscopy and biochemical experiments confirmed that SpA binds to the surface IgM/IgD complex and induces its clathrin-dependent internalization. Concomitantly, the SpA-induced signaling leads to protein kinase C–dependent CXCR4 downmodulation, suggesting that SpA impairs the recycling of CXCR4, a postclathrin process that leads to either degradation into lysozomes or de novo expression at the cell surface. In addition to providing novel insight into disruption of B-cell trafficking by an infectious agent, our findings may have therapeutic implications. Because CXCR4 has been associated with cancer metastasis and with certain autoimmune diseases, SpA behaves as an evolutionary tailored highly specific, chemokine receptor inhibitor that may have value in addition to conventional cytotoxic therapy in patients with various malignancies and immune-mediated diseases. PMID:22367177

Borhis, Gwenoline; Viau, Muriel; Badr, Gamal; Richard, Yolande; Zouali, Moncef

2012-01-01

329

HspB1, HspB5 and HspB4 in Human Cancers: Potent Oncogenic Role of Some of Their Client Proteins  

PubMed Central

Human small heat shock proteins are molecular chaperones that regulate fundamental cellular processes in normal unstressed cells as well as in many cancer cells where they are over-expressed. These proteins are characterized by cell physiology dependent changes in their oligomerization and phosphorylation status. These structural changes allow them to interact with many different client proteins that subsequently display modified activity and/or half-life. Nowdays, the protein interactomes of small Hsps are under intense investigations and will represent, when completed, key parameters to elaborate therapeutic strategies aimed at modulating the functions of these chaperones. Here, we have analyzed the potential pro-cancerous roles of several client proteins that have been described so far to interact with HspB1 (Hsp27) and its close members HspB5 (?B-crystallin) and HspB4 (?A-crystallin). PMID:24514166

Arrigo, André-Patrick; Gibert, Benjamin

2014-01-01

330

A human TRIM5? B30.2/SPRY domain mutant gains the ability to restrict and prematurely uncoat B-tropic murine leukemia virus  

PubMed Central

Human TRIM5? restricts N-tropic murine leukemia virus (N-MLV) but not B-tropic MLV (B-MLV) infection. Here we study B30.2/SPRY domain mutants of human TRIM5? that acquire the ability to inhibit B-MLV infection prior to reverse transcription without losing the ability to restrict N-MLV infection. Remarkably, these mutants gain the ability to decrease the amount of particulate B-MLV capsids in the cytosol of infected cells. In addition, these mutants gain the ability to restrict SIVmac and HIV-2 infection. B-MLV and SIVmac infections were blocked by the mutant TRIM5? proteins prior to reverse transcription. Thus, the range of retroviruses restricted by human TRIM5? can be increased by changes in the B30.2/SPRY domain, which also result in the ability to cause premature uncoating of the restricted retroviral capsid. PMID:18586294

Diaz-Griffero, Felipe; Perron, Michel; McGee-Estrada, Kathleen; Hanna, Robert; Maillard, Pierre; Trono, Didier; Sodroski, Joseph

2008-01-01

331

Gene copy numbers of erbB oncogenes in human pheochromocytoma.  

PubMed

ErbB-1, -2, -3 and -4 proteins are growth factor receptors, encoded by the family of respective erbB protooncogenes. These receptor-encoding proto-oncogenes frequently undergo amplification, and less frequently, a deletion, in several human neoplasms. The role of the ErbB family in human endocrine neoplasms, including pheochromocytoma (PHEO), was not extensively tested and not previously established. The expression/overexpression of erbB oncogenes in pheochromocytoma tissue was determined only in a few cases, and to the best of our knowledge, their mutations (amplification or deletion) were not examined in any series of PHEO cases. We, therefore, used a double differential polymerase chain reaction (ddPCR) for determination of the amplification/deletion profiles of erbB-1, -2, -3 and -4 genes in formalin-fixed, paraffin embedded (FFPE) specimens of human PHEOs. We examined the average gene copy number (AGCN) of the genes in 36 samples of pheochromocytomas (2 extra-adrenal and 34 adrenal tumors). We found the mean AGCNs of the oncogenes equal 1.18 for erbB-1 [amplification was found in 11/35 cases (31%) and deletion in 6/35 cases (17%)], 2.00 for erbB-2 [amplification was found in 8/34 cases (24%), no deletion was found], 1.36 for erbB-3 [amplification was found in 4/36 cases (11%) and deletion in 1/36 cases (3%)], and 1.22 for erbB-4 [amplification was found in 5/30 cases (17%) and deletion in 1/30 cases (3%)]. A mutation(s) of any erbB oncogene was found in 25/36 (69%) samples tested. Some abnormalities of the erbB oncogenes showed interesting correlations with one another and with clinical features of the tumors. The frequent occurrence of amplifications and deletions of the erbB oncogenes in human pheochromocytoma implies the importance of the gene family in the development of these tumors. PMID:12375051

Sworczak, Krzysztof; Zaczek, Anna; Babinska, Anna; Lisowska, Urszula; Bielawski, Krzysztof P; Falkiewicz, Bogdan

2002-01-01

332

Sparstolonin B suppresses lipopolysaccharide-induced inflammation in human umbilical vein endothelial cells  

PubMed Central

Sparstolonin B (SsnB) is an isocoumarin compound isolated from the tubers of both Sparganium stoloniferum and Scirpus yagara. We previously demonstrated that SsnB blocked the Toll-like receptor (TLR) 2- and TLR4-triggered inflammatory signaling in macrophages by inhibiting the recruitment of MyD88 to the TIR domains of TLR2 and TLR4. The present study was designed to examine the effects of SsnB on vascular inflammatory responses in human umbilical vein endothelial cells (HU-VECs) challenged by lipopolysaccharide (LPS, a TLR4 ligand). We found that SsnB dose-dependently attenuated the LPS-induced expression of interleukin (IL)-1? and monocyte chemoattractant protein 1 both at the transcription and translation levels in HUVEC. LPS-induced endothelial cell adhesion molecules, intercellular adhesion molecular-1 and vascular cell adhesion molecule-1 expressions were also reduced by treatment with SsnB. In addition, co-incubation with SsnB attenuated THP-1 monocyte adhesion to LPS-activated HUVECs. Furthermore, SsnB efficiently suppressed LPS-induced phosphorylation of extracellular-signal-regulated kinase (Erk1/2) and Akt in HUVECs. These findings show that SsnB can suppress endothelial cell inflammation, suggesting that SsnB might be suitable for development as a therapeutic agent for inflammatory cardiovascular disease. PMID:23604718

Yu, Fang; Cui, Xiaodong; Duan, Jin’ao; Wu, Qinan; Nagarkatti, Prakash

2014-01-01

333

Selective Induction of DNA Repair Pathways in Human B Cells Activated by CD4+ T Cells  

PubMed Central

Greater than 75% of all hematologic malignancies derive from germinal center (GC) or post-GC B cells, suggesting that the GC reaction predisposes B cells to tumorigenesis. Because GC B cells acquire expression of the highly mutagenic enzyme activation-induced cytidine deaminase (AID), GC B cells may require additional DNA repair capacity. The goal of this study was to investigate whether normal human B cells acquire enhanced expression of DNA repair factors upon AID induction. We first demonstrated that several DNA mismatch repair, homologous recombination, base excision repair, and ATR signaling genes were overexpressed in GC B cells relative to naïve and memory B cells, reflecting activation of a process we have termed somatic hyperrepair (SHR). Using an in vitro system, we next characterized activation signals required to induce AID expression and SHR. Although AID expression was induced by a variety of polyclonal activators, SHR induction strictly required signals provided by contact with activated CD4+ T cells, and B cells activated in this manner displayed reduced levels of DNA damage-induced apoptosis. We further show the induction of SHR is independent of AID expression, as GC B cells from AID -/- mice retained heightened expression of SHR proteins. In consideration of the critical role that CD4+ T cells play in inducing the SHR process, our data suggest a novel role for CD4+ T cells in the tumor suppression of GC/post-GC B cells. PMID:21179576

Wu, Xiaosheng; Tschumper, Renee C.; Gutierrez, Albert; Mihalcik, Stephen A.; Nowakowski, Grzegorz S.; Jelinek, Diane F.

2010-01-01

334

UV-A-induced decrease in nuclear factor-kappaB activity in human keratinocytes.  

PubMed Central

Previous reports have demonstrated an increase in nuclear factor-kappaB (NF-kappaB) activity in response to UV radiation. These studies have essentially focused on the DNA-damaging fraction of solar UV radiation (UV-B and UV-C). In contrast, the effects of UV-A radiation (320-400 nm) on NF-kappaB are not well known. In this study, we present evidence that UV-A radiation induces a marked decrease in NF-kappaB DNA-binding activity in NCTC 2544 human keratinocytes. In addition, NCTC 2544 keratinocytes pretreated with UV-A fail to respond to NF-kappaB inducers. Moreover, UV-A radiation induces a decrease in NF-kappaB-driven luciferase reporter gene expression in NCTC 2544 keratinocytes. The expression of the gene encoding IkappaBalpha (IkappaB is the NF-kappaB inhibitor), which is closely associated with NF-kappaB activity, is also reduced (3-fold) upon UV-A treatment. Our results indicate that the UV-A-induced decrease in NF-kappaB DNA-binding activity is associated with a decrease in the levels of the p50 and p65 protein subunits. This is the first evidence that an oxidative stress, such as UV-A radiation, may induce a specific decrease in NF-kappaB activity in mammalian cells, probably through degradation of NF-kappaB protein subunits. These findings suggest that UV-A could modulate the NF-kappaB-dependent gene expression. PMID:10051429

Djavaheri-Mergny, M; Gras, M P; Mergny, J L; Dubertret, L

1999-01-01

335

Competitive chemiluminescent anzyme immunoassay for vitamin B12 analysis in human milk.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Recent discoveries of matrix interferences by haptocorrin (HC) in human milk and serum show that past analyses of vitamin B12 in samples with high HC content might have been inaccurate (Lildballe et al., 2009; Carmel & Agrawal, 2012). We evaluated two competitive enzyme-binding immunoassays for seru...

336

How robust is human gait to muscle weakness? Marjolein M. van der Krogt a,b,  

E-print Network

. Disuse, aging, and disease can lead to a loss of muscle strength, which may limit the performance movements requiring agility, timing, and strength. Disuse, aging, and disease can lead to a loss of muscleHow robust is human gait to muscle weakness?§ Marjolein M. van der Krogt a,b, *, Scott L. Delp c

Delp, Scott

337

The Nucleotide Sequence of Human Rhinovirus 1B: Molecular Relationships within the Rhinovirus Genus  

Microsoft Academic Search

SUMMARY We have determined the complete nucleotide sequence of human rhinovirus 1B and made comparisons with other rhinoviruses. Extensive homology was found with serotypes 2 and 89 but the similarity to serotype 14 was considerably less. Rhinovirus- specific characteristics have been noted, in particular the length of the 5' non-coding region and the pattern of codon usage, and these may

PAMELA J. HUGHES; CHRISTINE NORTH; CHRISTOPHER H. JELLIS; PHILIP D. MINOR; GLYN STANWAY

1988-01-01

338

Bordetella pertussis, the Causative Agent of Whooping Cough, Evolved from a Distinct, Human-Associated Lineage of B. bronchiseptica  

PubMed Central

Bordetella pertussis, B. bronchiseptica, B. parapertussishu, and B. parapertussisov are closely related respiratory pathogens that infect mammalian species. B. pertussis and B. parapertussishu are exclusively human pathogens and cause whooping cough, or pertussis, a disease that has resurged despite vaccination. Although it most often infects animals, infrequently B. bronchiseptica is isolated from humans, and these infections are thought to be zoonotic. B. pertussis and B. parapertussishu are assumed to have evolved from a B. bronchiseptica–like ancestor independently. To determine the phylogenetic relationships among these species, housekeeping and virulence genes were sequenced, comparative genomic hybridizations were performed using DNA microarrays, and the distribution of insertion sequence elements was determined, using a collection of 132 strains. This multifaceted approach distinguished four complexes, representing B. pertussis, B. parapertussishu, and two distinct B. bronchiseptica subpopulations, designated complexes I and IV. Of the two B. bronchiseptica complexes, complex IV was more closely related to B. pertussis. Of interest, while only 32% of the complex I strains were isolated from humans, 80% of the complex IV strains were human isolates. Comparative genomic hybridization analysis identified the absence of the pertussis toxin locus and dermonecrotic toxin gene, as well as a polymorphic lipopolysaccharide biosynthesis locus, as associated with adaptation of complex IV strains to the human host. Lipopolysaccharide structural diversity among these strains was confirmed by gel electrophoresis. Thus, complex IV strains may comprise a human-associated lineage of B. bronchiseptica from which B. pertussis evolved. These findings will facilitate the study of pathogen host-adaptation. Our results shed light on the origins of the disease pertussis and suggest that the association of B. pertussis with humans may be more ancient than previously assumed. PMID:16389302

Diavatopoulos, Dimitri A; Cummings, Craig A; Schouls, Leo M; Brinig, Mary M; Relman, David A; Mooi, Frits R

2005-01-01

339

BDNF/TrkB signaling protects HT-29 human colon cancer cells from EGFR inhibition  

SciTech Connect

Highlights: Black-Right-Pointing-Pointer BDNF protected HT-29 colorectal cancer cells from the antitumor effect of cetuximab. Black-Right-Pointing-Pointer TrkB inhibition potentiated the antitumor effect of cetuximab. Black-Right-Pointing-Pointer BDNF/TrkB signaling might be involved in resistance to anti-EGFR therapy. -- Abstract: The clinical success of targeted treatment of colorectal cancer (CRC) is often limited by resistance to anti-epidermal growth factor receptor (EGFR) therapy. The neurotrophin brain-derived neurotrophic factor (BDNF) and its receptor TrkB have recently emerged as anticancer targets, and we have previously shown increased BDNF levels in CRC tumor samples. Here we report the findings from in vitro experiments suggesting that BDNF/TrkB signaling can protect CRC cells from the antitumor effects of EGFR blockade. The anti-EGFR monoclonal antibody cetuximab reduced both cell proliferation and the mRNA expression of BDNF and TrkB in human HT-29 CRC cells. The inhibitory effect of cetuximab on cell proliferation and survival was counteracted by the addition of human recombinant BDNF. Finally, the Trk inhibitor K252a synergistically enhanced the effect of cetuximab on cell proliferation, and this effect was blocked by BDNF. These results provide the first evidence that increased BDNF/TrkB signaling might play a role in resistance to EGFR blockade. Moreover, it is possible that targeting TrkB could potentiate the anticancer effects of anti-EGFR therapy.

Brunetto de Farias, Caroline [Cancer Research Laboratory, University Hospital Research Center (CPE-HCPA), Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil) [Cancer Research Laboratory, University Hospital Research Center (CPE-HCPA), Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil); Children's Cancer Institute, 90420-140 Porto Alegre, RS (Brazil); Laboratory of Neuropharmacology and Neural Tumor Biology, Department of Pharmacology, Institute for Basic Health Sciences, Federal University of Rio Grande do Sul, 90050-170 Porto Alegre, RS (Brazil); National Institute for Translational Medicine (INCT-TM), 90035-003 Porto Alegre, RS (Brazil); Heinen, Tiago Elias; Pereira dos Santos, Rafael [Cancer Research Laboratory, University Hospital Research Center (CPE-HCPA), Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil) [Cancer Research Laboratory, University Hospital Research Center (CPE-HCPA), Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil); Laboratory of Neuropharmacology and Neural Tumor Biology, Department of Pharmacology, Institute for Basic Health Sciences, Federal University of Rio Grande do Sul, 90050-170 Porto Alegre, RS (Brazil); National Institute for Translational Medicine (INCT-TM), 90035-003 Porto Alegre, RS (Brazil); Abujamra, Ana Lucia [Cancer Research Laboratory, University Hospital Research Center (CPE-HCPA), Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil) [Cancer Research Laboratory, University Hospital Research Center (CPE-HCPA), Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil); Children's Cancer Institute, 90420-140 Porto Alegre, RS (Brazil); National Institute for Translational Medicine (INCT-TM), 90035-003 Porto Alegre, RS (Brazil); Schwartsmann, Gilberto [Cancer Research Laboratory, University Hospital Research Center (CPE-HCPA), Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil) [Cancer Research Laboratory, University Hospital Research Center (CPE-HCPA), Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil); National Institute for Translational Medicine (INCT-TM), 90035-003 Porto Alegre, RS (Brazil); Department of Internal Medicine, School of Medicine, Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil); and others

2012-08-24

340

Global reemergence of enterovirus D68 as an important pathogen for acute respiratory infections.  

PubMed

We previously detected enterovirus D68 (EV-D68) in children with severe acute respiratory infections in the Philippines in 2008-2009. Since then, the detection frequency of EV-D68 has increased in different parts of the world, and EV-D68 is now recognized as a reemerging pathogen. However, the epidemiological profile and clinical significance of EV-D68 is yet to be defined, and the virological characteristics of EV-D68 are not fully understood. Recent studies have revealed that EV-D68 is detected among patients with acute respiratory infections of differing severities ranging from mild upper respiratory tract infections to severe pneumonia including fatal cases in pediatric and adult patients. In some study sites, the EV-D68 detection rate was higher among patients with lower respiratory tract infections than among those with upper respiratory tract infections, suggesting that EV-D68 infections are more likely to be associated with severe respiratory illnesses. EV-D68 strains circulating in recent years have been divided into three distinct genetic lineages with different antigenicity. However, the association between genetic differences and disease severity, as well as the occurrence of large-scale outbreaks, remains elusive. Previous studies have revealed that EV-D68 is acid sensitive and has an optimal growth temperature of 33?°C. EV-D68 binds to ?2,6-linked sialic acids; hence, it is assumed that it has an affinity for the upper respiratory track where these glycans are present. However, the lack of suitable animal model constrains comprehensive understanding of the pathogenesis of EV-D68. © 2014 The Authors. Reviews in Medical Virology published by John Wiley & Sons Ltd. PMID:25471236

Imamura, Tadatsugu; Oshitani, Hitoshi

2014-12-01

341

Lineages, Sub-Lineages and Variants of Enterovirus 68 in Recent Outbreaks  

PubMed Central

Enterovirus 68 (EV68) was first isolated in 1962. Very few cases of EV68 infection were described over the ensuing 40 years. However, in the past few years, an increase in severe respiratory tract infections associated with EV68 has been reported. We identified two clusters of EV68 infection in South London, UK, one each in the autumn/winters of 2009 and 2010. Sequence comparison showed significant homology of the UK strains with those from other countries including the Netherlands, Japan and the Philippines, which reported EV68 outbreaks between 2008 and 2010. Phylogenetic analysis of all available VP1 sequences indicated the presence of two modern EV68 lineages. The 2010 UK strains belonged to lineage 2. Lineage 1 could be further divided into two sub-lineages: some Japanese and Dutch strains collected between 2004 and 2010 form a distinct sub-lineages (sub-lineage 1.1), whereas other strains from the UK, Japan, Netherlands and Philippines collected between 2008 and 2010 represent sub-lineage 1.2. The UK 2009 strains together with several Dutch and Japanese strains from 2009/2010 represents one variant (1.2.1), whereas those from the Philippines a second variant (1.2.2). Based on specific deletions and substitutions, we suggest rules for the assignment of lineages and sub-lineages. Molecular epidemiological analysis indicates rapid recent evolution of EV68 and this may explain the recent findings of a global resurgence of EV68. Continuous global monitoring of the clinical and molecular epidemiology of EV68 is recommended. PMID:22536453

Lauinger, Ina L.; Bible, Jon M.; Halligan, Eugene P.; Aarons, Emma J.; MacMahon, Eithne; Tong, Cheuk Y. W.

2012-01-01

342

Chlorine dioxide inactivation of enterovirus 71 in water and its impact on genomic targets.  

PubMed

To control the waterborne transmission of enterovirus 71(EV71), which is associated with hand foot and mouth disease (HFMD), it is essential to know the inactivation effectiveness of disinfectants on EV71 in water. In this article, we present a comparative analysis of the effects on EV71 following exposure to chlorine dioxide (ClO2) under different doses, pH, and temperature conditions. We show that the EV71 exhibited strong resistance to ClO2 (more than the MS2 standard) and that Ct value ranges required for a 4-log reduction of EV71 in buffered, disinfectant demand-free water at pH 7.2 and 20 °C by ClO2 were 4.24-6.62 mg/L·min according to the efficiency factor Hom model. ClO2 inactivation of the virus was temperature- and pH-dependent. The virucidal efficiency was higher at pH 8.2 than at pH 5.6 and pH 7.2 and higher at 36 °C than at 4 and 20 °C. In addition, we also observed the impact of ClO2 on the entire viral genome using RT-PCR, which indicated that the 5' noncoding region (5'-NCR) within the EV71 genome, specifically the 1-118 nt region, was the most easily damaged by ClO2 and correlated with viral infectivity. Our study has not only provided guidelines for EV71 disinfection strategies of waste and drinking water, but also confirmed the importance of the 5'-NCR for EV71 infectivity and may demonstrate a general inactivation by ClO2 of enteric virus by damaging the 5'-NCR. Furthermore, 5'-NCR can be used as a target region for PCR to investigate infectious virus contamination in environmental water and evaluate the inactivation effects of ClO2. PMID:23560857

Jin, Min; Shan, Jinyang; Chen, Zhaoli; Guo, Xuan; Shen, Zhiqiang; Qiu, Zhigang; Xue, Bin; Wang, Yongguang; Zhu, Dunwan; Wang, Xinwei; Li, Junwen

2013-05-01

343

Enterovirus 71 Uses Cell Surface Heparan Sulfate Glycosaminoglycan as an Attachment Receptor  

PubMed Central

Enterovirus 71 (EV-71) infections are usually associated with mild hand, foot, and mouth disease in young children but have been reported to cause severe neurological complications with high mortality rates. To date, four EV-71 receptors have been identified, but inhibition of these receptors by antagonists did not completely abolish EV-71 infection, implying that there is an as yet undiscovered receptor(s). Since EV-71 has a wide range of tissue tropisms, we hypothesize that EV-71 infections may be facilitated by using receptors that are widely expressed in all cell types, such as heparan sulfate. In this study, heparin, polysulfated dextran sulfate, and suramin were found to significantly prevent EV-71 infection. Heparin inhibited infection by all the EV-71 strains tested, including those with a single-passage history. Neutralization of the cell surface anionic charge by polycationic poly-d-lysine and blockage of heparan sulfate by an anti-heparan sulfate peptide also inhibited EV-71 infection. Interference with heparan sulfate biosynthesis either by sodium chlorate treatment or through transient knockdown of N-deacetylase/N-sulfotransferase-1 and exostosin-1 expression reduced EV-71 infection in RD cells. Enzymatic removal of cell surface heparan sulfate by heparinase I/II/III inhibited EV-71 infection. Furthermore, the level of EV-71 attachment to CHO cell lines that are variably deficient in cell surface glycosaminoglycans was significantly lower than that to wild-type CHO cells. Direct binding of EV-71 particles to heparin-Sepharose columns under physiological salt conditions was demonstrated. We conclude that EV-71 infection requires initial binding to heparan sulfate as an attachment receptor. PMID:23097443

Tan, Chee Wah; Poh, Chit Laa; Sam, I-Ching

2013-01-01

344

Enterovirus 71 uses cell surface heparan sulfate glycosaminoglycan as an attachment receptor.  

PubMed

Enterovirus 71 (EV-71) infections are usually associated with mild hand, foot, and mouth disease in young children but have been reported to cause severe neurological complications with high mortality rates. To date, four EV-71 receptors have been identified, but inhibition of these receptors by antagonists did not completely abolish EV-71 infection, implying that there is an as yet undiscovered receptor(s). Since EV-71 has a wide range of tissue tropisms, we hypothesize that EV-71 infections may be facilitated by using receptors that are widely expressed in all cell types, such as heparan sulfate. In this study, heparin, polysulfated dextran sulfate, and suramin were found to significantly prevent EV-71 infection. Heparin inhibited infection by all the EV-71 strains tested, including those with a single-passage history. Neutralization of the cell surface anionic charge by polycationic poly-d-lysine and blockage of heparan sulfate by an anti-heparan sulfate peptide also inhibited EV-71 infection. Interference with heparan sulfate biosynthesis either by sodium chlorate treatment or through transient knockdown of N-deacetylase/N-sulfotransferase-1 and exostosin-1 expression reduced EV-71 infection in RD cells. Enzymatic removal of cell surface heparan sulfate by heparinase I/II/III inhibited EV-71 infection. Furthermore, the level of EV-71 attachment to CHO cell lines that are variably deficient in cell surface glycosaminoglycans was significantly lower than that to wild-type CHO cells. Direct binding of EV-71 particles to heparin-Sepharose columns under physiological salt conditions was demonstrated. We conclude that EV-71 infection requires initial binding to heparan sulfate as an attachment receptor. PMID:23097443

Tan, Chee Wah; Poh, Chit Laa; Sam, I-Ching; Chan, Yoke Fun

2013-01-01

345

Quantitative RT-PCR Detection of Hepatitis A Virus, Rotaviruses and Enteroviruses in the Buffalo River and Source Water Dams in the Eastern Cape Province of South Africa  

PubMed Central

Human enteric viruses (HEntVs) are a major cause of water-related diseases. The prevalence of hepatitis A virus (HAV), rotaviruses (RoV) and enteroviruses (EnV) in Buffalo River waters was assessed quantitatively over a period of 12 months (August 2010 to July 2011). Seventy-two samples were collected from six sites, including three dams, and concentrated using the adsorption-elution method. Viral RNA was extracted using a commercial kit, and the viruses were quantified by real-time quantitative reverse transcriptase PCR (RT-qPCR). Two or more viruses were detected in 12.5% of the samples. HAV was detected in 43.1% of the samples and in significantly (p < 0.05) varying concentrations of 1.5 × 101–1.9 × 105 genome copies/L compared to RoV and EnV, while RoVs were detected in 13.9% of samples, with concentrations ranging from 2.5 × 101–2.1 × 103 genome copies/L, and EnV were detected in 9.7% of the samples, with concentrations ranging from 1.3 × 101–8.6 × 101 genome copies/L. Only HAV was detected at all the sites, with the Bridle Drift Dam recording significantly higher (p < 0.05) concentrations. The presence of enteric viruses in Buffalo River may constitute public health risks and the incidence of HAV at all the sites could reflect both the epidemiological status of hepatitis A and HAV persistence in the water environments. PMID:23202829

Chigor, Vincent Nnamdigadi; Okoh, Anthony Ifeanyi

2012-01-01

346

Prediction of signaling pathways involved in enterovirus 71 infection by algorithm analysis based on miRNA profiles and their target genes.  

PubMed

Enterovirus 71 (EV71) causes major outbreaks of hand, foot, and mouth disease. Host factors and signaling pathways exhibit important functions in the EV71 life cycle. We conducted algorithm analysis based on miRNA profiles and their target genes to identify the miRNAs and downstream signaling pathways involved in EV71 infection. The miRNA profiles of human rhabdomyosarcoma cells treated with interferon (IFN-)-? or IFN-? were compared with those of cells infected with EV71. Genes targeted by differentially expressed miRNAs were identified and assigned to different signaling pathways according to public databases. The results showed that host miRNAs specifically responded to the viral infection and IFN treatment. Some miRNAs, including miR-124 and miR-491-3p, were regulated in opposite manners by the IFNs and EV71. Some signaling pathways regulated by both EV71 infection and IFN treatment were also predicted. These pathways included axon guidance, Wingless/Int1 (Wnt) signaling cascade, platelet-derived growth factor receptor (PDGFR)/PDGF, phosphatidylinositol 3-kinase (PI3K), Jun N-terminal kinase (JNK)/mitogen-activated protein kinase (MAPK), transforming growth factor-beta receptor (TGF-?R)/TGF-?, SMAD2/3, insulin/insulin-like growth factor (IGF), bone morphogenetic protein (BMP), CDC42, ERB1, hepatocyte growth factor receptor (c-Met), eukaryotic translation initiation factor 4E (eIF4E), protein kinase A (PKA), and IFN-? pathways. The identified miRNA and downstream signaling pathways would help to elucidate the interaction between the virus and the host. The genomics method using algorithm analysis also provided a new way to investigate the host factors and signaling pathways critical for viral replication. PMID:25287131

Bian, Liang; Wang, Yan; Liu, Qingqing; Xia, Jufeng; Long, Jian-Er

2015-01-01

347

Sensorless Interaction Force Control Based on B-Spline Function for Human-Robot Systems  

NASA Astrophysics Data System (ADS)

In this paper, to provide precise force sensation of human operator, a twin direct-drive motor system with wire rope mechanism has been developed. The human-robot interaction force and the wire rope tension are independently controlled in acceleration dimension by realizing the dual disturbance observer based on modal space design. In the common mode, it is utilized for control of vibration suppression and wire rope tension. In the differential mode, the purity of human external force with compensation of friction force is obtained. This mode is useful for control of the interaction force of human. Furthermore, the human-robot system that has the ability of support of human interaction force is also proposed. The interaction force generation based on B-spline function is applied to automatically adjust the smooth force command corresponding to the adaptive parameters.
To analyze the human movement stroke, the multi-sensor scheme is applied to fuse both two motor encoders and acceleration sensor signal by using Kalman filter. From the experimental results, the ability to design different level of assistive force makes it well suited to customized training programs due to time and human movement constraints.

Mitsantisuk, Chowarit; Katsura, Seiichiro; Ohishi, Kiyoshi

348

Arterial Shear Stress Reduces Eph-B4 Expression in Adult Human Veins  

PubMed Central

Vein graft adaptation to the arterial environment is characterized by loss of venous identity, with reduced Ephrin type-B receptor 4 (Eph-B4) expression but without increased Ephrin-B2 expression. We examined changes of vessel identity of human saphenous veins in a flow circuit in which shear stress could be precisely controlled. Medium circulated at arterial or venous magnitudes of laminar shear stress for 24 hours; histologic, protein, and RNA analyses of vein segments were performed. Vein endothelium remained viable and functional, with platelet endothelial cell adhesion molecule (PECAM)-expressing cells on the luminal surface. Venous Eph-B4 expression diminished (p = .002), Ephrin-B2 expression was not induced (p = .268), and expression of osteopontin (p = .002) was increased with exposure to arterial magnitudes of shear stress. Similar changes were not found in veins placed under venous flow or static conditions. These data show that human saphenous veins remain viable during ex vivo application of shear stress in a bioreactor, without loss of the venous endothelium. Arterial magnitudes of shear stress cause loss of venous identity without gain of arterial identity in human veins perfused ex vivo. Shear stress alone, without immunologic or hormonal influence, is capable of inducing changes in vessel identity and, specifically, loss of venous identity. PMID:25191151

Model, Lynn S.; Hall, Michael R.; Wong, Daniel J.; Muto, Akihito; Kondo, Yuka; Ziegler, Kenneth R.; Feigel, Amanda; Quint, Clay; Niklason, Laura; Dardik, Alan

2014-01-01

349

Myosin heavy chain-2b transcripts and isoform are expressed in human laryngeal muscles.  

PubMed

Three fast myosin heavy chain (MyHC) isoforms, i.e. MyHC-2a, -2x and -2b, are expressed in skeletal muscles of smaller mammals. In contrast, only MyHC-2a and -2x have been revealed in humans so far. The expression of MyHC isoforms is known to be wider in the functionally more specialized laryngeal muscles. Though mRNA transcripts of the MyHC-2b gene were found to be expressed in certain human skeletal and laryngeal muscles, the corresponding isoform has not been demonstrated in these muscles. To our knowledge, we are the first to demonstrate not only the expression of MyHC-2b transcripts using an in situ hybridization technique but also the corresponding protein, i.e. the MyHC-2b isoform, in some human laryngeal muscles by immunohistochemistry but not by polyacrylamide gel electrophoresis. Using a set of antibodies specific to MyHC isoforms, we demonstrated that MyHC-2b was always co-expressed with the major MyHC isoforms, not only with the fast ones (MyHC-2a and -2x) but with the slow isoform (MyHC-1) as well. PMID:23796659

Smerdu, Vika; Cvetko, Erika

2013-01-01

350

Arterial shear stress reduces eph-b4 expression in adult human veins.  

PubMed

Vein graft adaptation to the arterial environment is characterized by loss of venous identity, with reduced Ephrin type-B receptor 4 (Eph-B4) expression but without increased Ephrin-B2 expression. We examined changes of vessel identity of human saphenous veins in a flow circuit in which shear stress could be precisely controlled. Medium circulated at arterial or venous magnitudes of laminar shear stress for 24 hours; histologic, protein, and RNA analyses of vein segments were performed. Vein endothelium remained viable and functional, with platelet endothelial cell adhesion molecule (PECAM)-expressing cells on the luminal surface. Venous Eph-B4 expression diminished (p = .002), Ephrin-B2 expression was not induced (p = .268), and expression of osteopontin (p = .002) was increased with exposure to arterial magnitudes of shear stress. Similar changes were not found in veins placed under venous flow or static conditions. These data show that human saphenous veins remain viable during ex vivo application of shear stress in a bioreactor, without loss of the venous endothelium. Arterial magnitudes of shear stress cause loss of venous identity without gain of arterial identity in human veins perfused ex vivo. Shear stress alone, without immunologic or hormonal influence, is capable of inducing changes in vessel identity and, specifically, loss of venous identity. PMID:25191151

Model, Lynn S; Hall, Michael R; Wong, Daniel J; Muto, Akihito; Kondo, Yuka; Ziegler, Kenneth R; Feigel, Amanda; Quint, Clay; Niklason, Laura; Dardik, Alan

2014-09-01

351

TLR4 activates NF-{kappa}B in human ovarian granulosa tumor cells  

SciTech Connect

Highlights: {yields} TLR4 is expressed in human ovarian granulosa tumor cells. {yields} Acting through TLR4, LPS and HSP60 induce a NF{kappa}B signaling cascade in human ovarian granulosa tumor cells. {yields} NF{kappa}B activation or inhibition did not alter chemosensitivity to TRAIL or cisplatin. -- Abstract: Previous studies have demonstrated expression of Toll-like receptors (TLRs) in the surface epithelium of normal ovaries (OSE) and in epithelial ovarian tumors. Most notably, OSE-derived cancers express TLR4, which activates the nuclear factor-kappa B (NF-{kappa}B) signaling cascade as a mediator of inflammatory response. Currently, there is considerable interest in elucidating the role of TLR-mediated signaling in cancers. Nevertheless, the expression of TLRs in granulosa cell tumors (GCTs) of the ovary, and the extent to which GCT expression of TLRs may influence cell-signaling pathways and/or modulate the efficacy of chemotherapeutics, has yet to be determined. In the present study, human GCT lines (COV434 and KGN) were utilized to evaluate expression of functional TLR4. TLR4 is expressed in GCT cell lines and ligation of TLR4 with bacterial lipopolysaccharide (LPS) led to I{kappa}B degradation and activation of NF-{kappa}B. NF-{kappa}B activation was confirmed by nuclear localization of NF-{kappa}B p65 following treatment with LPS and the naturally occurring ligand, HSP60. Notably, immunoneutralization of TLR4 blocked nuclear localization, and inhibition of NF-{kappa}B signaling attenuated LPS-induced TNF{alpha} plus increased doubling time in both cell lines. Contradictory to reports using human OSE cell lines, inhibition of NF-{kappa}B signaling failed to sensitize GCT lines to TRAIL or cisplatin. In summary, findings herein are the first to demonstrate a functional TLR-signaling pathway specifically in GCTs, and indicate that in contrast to OSE-derived cancers, inhibition of NF-{kappa}B does not sensitize GCTs to TRAIL or cisplatin.

Woods, Dori C., E-mail: dwoods2@partners.org [Vincent Center for Reproductive Biology, Vincent Obstetrics and Gynecology Service, Massachusetts General Hospital/Harvard Medical School, Boston, MA 02114 (United States); White, Yvonne A.R. [Vincent Center for Reproductive Biology, Vincent Obstetrics and Gynecology Service, Massachusetts General Hospital/Harvard Medical School, Boston, MA 02114 (United States)] [Vincent Center for Reproductive Biology, Vincent Obstetrics and Gynecology Service, Massachusetts General Hospital/Harvard Medical School, Boston, MA 02114 (United States); Dau, Caroline [University of California, San Francisco, School of Dentistry, San Francisco, CA 94143 (United States)] [University of California, San Francisco, School of Dentistry, San Francisco, CA 94143 (United States); Johnson, A.L. [Center for Reproductive Biology and Health, The Pennsylvania State University, University Park, PA 16802 (United States)] [Center for Reproductive Biology and Health, The Pennsylvania State University, University Park, PA 16802 (United States)

2011-06-17

352

Quantitation of human parvovirus B19 DNA in erythema infectiosum and aplastic crisis.  

PubMed

Several publications concerning the methods of real-time PCR for human parvovirus B19 (B19V) have appeared and some case reports mention B19V DNA loads. However, no large-scale study quantitating levels of B19V DNA in common or representative B19V manifestations such as erythema infectiosum and aplastic crisis has been performed. Consequently, using the TaqMan PCR assay, the B19V load in a large sample of subjects with erythema infectiosum or aplastic crisis was quantitated. Sixty-five subjects in the acute phase of erythema infectiosum were involved, and in addition 22 serum samples from seven subjects with B19V-associated aplastic crisis complicating chronic hemolytic anemia were also analyzed. In the acute phase of erythema infectiosum the median B19V DNA load in the serum samples from the acute phase of erythema infectiosum was 7.63?×?10(5) ?genomes/ml, (range from 4.48?×?10(3) to 8.31?×?10(6) ?genomes/ml). The serum B19V DNA load during the acute phase of aplastic crisis complicating chronic hemolytic anemia was extremely high, that is 10(10) -10(13) ?genomes/ml, and decreased gradually to around 10(5) genomes/ml over 1-2 months. Although all subjects followed an almost uniform and typical clinical course of erythema infectiosum, there was a large individual variation of B19V DNA loads, that is differences of over 1,000 times. Extremely high B19V loads were observed in subjects with aplastic crisis. This study is the first large scale report of studies of the B19V DNA loads in subjects with erythema infectiosum and aplastic crisis, the most common and significant clinical manifestations by B19V infections. PMID:24962467

Ishikawa, Aki; Yoto, Yuko; Tsugawa, Takeshi; Tsutsumi, Hiroyuki

2014-12-01

353

A human skeletal overgrowth mutation increases maximal velocity and blocks desensitization of guanylyl cyclase-B.  

PubMed

C-type natriuretic peptide (CNP) increases long bone growth by stimulating guanylyl cyclase (GC)-B/NPR-B/NPR2. Recently, a Val to Met missense mutation at position 883 in the catalytic domain of GC-B was identified in humans with increased blood cGMP levels that cause abnormally long bones. Here, we determined how this mutation activates GC-B. In the absence of CNP, cGMP levels in cells expressing V883M-GC-B were increased more than 20 fold compared to cells expressing wild-type (WT)-GC-B, and the addition of CNP only further increased cGMP levels 2-fold. In the absence of CNP, maximal enzymatic activity (Vmax) of V883M-GC-B was increased 15-fold compared to WT-GC-B but the affinity of the enzymes for substrate as revealed by the Michaelis constant (Km) was unaffected. Surprisingly, CNP decreased the Km of V883M-GC-B 10-fold in a concentration-dependent manner without increasing Vmax. Unlike the WT enzyme the Km reduction of V883M-GC-B did not require ATP. Unexpectedly, V883M-GC-B, but not WT-GC-B, failed to inactivate with time. Phosphorylation elevated but was not required for the activity increase associated with the mutation because the Val to Met substitution also activated a GC-B mutant lacking all known phosphorylation sites. We conclude that the V883M mutation increases maximal velocity in the absence of CNP, eliminates the requirement for ATP in the CNP-dependent Km reduction, and disrupts the normal inactivation process. PMID:23827346

Robinson, Jerid W; Dickey, Deborah M; Miura, Kohji; Michigami, Toshimi; Ozono, Keiichi; Potter, Lincoln R

2013-10-01

354

Probing the binding of procyanidin B3 to human serum albumin by isothermal titration calorimetry  

NASA Astrophysics Data System (ADS)

Proanthocyanidins are a mixture of monomers, oligomers, and polymers of flavan-3-ols that are widely distributed in the plant kingdom. One of the most widely studied proanthocyanidins is procyanidin B3. In this study, the interaction between procyanidin B3 and human serum albumin (HSA) was investigated using isothermal titration calorimetry (ITC). Thermodynamic investigations reveal that the hydrogen bond and van der Waals force are the major binding forces in the binding of procyanidin B3 to HSA. The binding of procyanidin B3 to HSA is driven by favorable enthalpy and unfavorable entropy. The obtained binding constant for procyanidin B3 with HSA is in the intermediate range and the equilibrium fraction of unbound procyanidin B3 fu > 90% at the physiological concentration of HSA shows that procyanidin B3 can be stored and transported from the circulatory system to reach its target site. The stoichiometric binding number n approximately equals to 1, suggesting that one molecule of procyanidin B3 combines with one molecule of HSA and no more procyanidin B3 binding to HSA occurs at the concentration used in this study.

Li, Xiangrong; Yan, Yunhui

2015-02-01

355

Poc1A and Poc1B act together in human cells to ensure centriole integrity.  

PubMed

Proteomic studies in unicellular eukaryotes identified a set of centriolar proteins that included proteome of centriole 1 (Poc1). Functional studies in these organisms implicated Poc1 in centriole duplication and length control, as well as ciliogenesis. Using isoform-specific antibodies and RNAi depletion, we have examined the function of the two related human proteins, Poc1A and Poc1B. We find that Poc1A and Poc1B each localize to centrioles and spindle poles, but do so independently and with different dynamics. However, although loss of one or other Poc1 protein does not obviously disrupt mitosis, depletion of both proteins leads to defects in spindle organization with the generation of unequal or monopolar spindles. Our data indicate that, once incorporated, a fraction of Poc1A and Poc1B remains stably associated with parental centrioles, but that depletion prevents incorporation into nascent centrioles. Nascent centrioles lacking both Poc1A and Poc1B exhibit loss of integrity and maturation, and fail to undergo duplication. Thus, when Poc1A and Poc1B are co-depleted, new centrosomes capable of maturation cannot assemble and unequal spindles result. Interestingly, Poc1B, but not Poc1A, is phosphorylated in mitosis, and depletion of Poc1B alone was sufficient to perturb cell proliferation. Hence, Poc1A and Poc1B play redundant, but essential, roles in generation of stable centrioles, but Poc1B may have additional independent functions during cell cycle progression. PMID:23015594

Venoux, Magali; Tait, Xavier; Hames, Rebecca S; Straatman, Kees R; Woodland, Hugh R; Fry, Andrew M

2013-01-01

356

Identification of enterovirus 71 isolates from an outbreak of hand, foot and mouth disease (HFMD) with fatal cases of encephalomyelitis in Malaysia  

Microsoft Academic Search

Thirteen enterovirus 71 (EV71) isolates were obtained from both fatal and non-fatal infections of patients seen in Peninsula Malaysia and in Sarawak during an outbreak of hand, foot and mouth disease (HFMD) in Malaysia in 1997, with incidences of fatal brainstem encephalomyelitis. The isolates were identified using immunofluorescence staining, neutralization assays, and partial sequencing of the 5? untranslated regions (UTR).

Sazaly AbuBakar; Hui-Yee Chee; Muhannad F. Al-Kobaisi; Jiang Xiaoshan; Kaw Bing Chua; Sai Kit Lam

1999-01-01

357

Assessment of an Enterovirus Sewage Surveillance System by Comparison of Clinical Isolates with Sewage Isolates from Milwaukee, Wisconsin, Collected August 1994 to December 2002  

Microsoft Academic Search

The quantity and serotypes of enteroviruses (EVs) in the influent of a local sewage treatment plant were compared to local clinical EV cases to determine if testing of sewage is adequate for an EV surveillance system. The study was carried out from August 1994 to December 2002. Monthly influent specimens were processed by organic flocculation, and dilutions of concentrate were

Gerald Sedmak; David Bina; Jeffrey MacDonald

2003-01-01

358

DETECTION OF ENVIRONMENTAL VIRUSES IN SLUDGE: ENHANCEMENT OF ENTEROVIRUS PLAQUE ASSAY TITERS WITH 5-IODO-2'-DEOXYURIDINE AND COMPARISON TO ADENOVIRUS AND COLIPHAGE TITERS (JOURNAL VERSION)  

EPA Science Inventory

Enteroviruses present in the primary sludge of two wastewater treatment plants were quantitated by plaque assay using a continuous African green monkey kidney cell line (BGM). Incubation of BGM monolayers with 5-iodo-2'-deoxyuridine (50 micrograms/ml) for 4 days prior to use enha...

359

Reticulon 3 interacts with NS4B of the hepatitis C virus and negatively regulates viral replication by disrupting NS4B self-interaction.  

PubMed

The non-structural protein 4B (NS4B) of the hepatitis C virus (HCV) is an endoplasmic reticulum (ER) membrane protein comprising two consecutive amphipathic ?-helical domains (AH1 and AH2). Its self-oligomerization via the AH2 domain is required for the formation of the membranous web that is necessary for viral replication. Previously, we reported that the host-encoded ER-associated reticulon 3 (RTN3) protein is involved in the formation of the replication-associated membranes of (+)RNA enteroviruses during viral replication. In this study, we demonstrated that the second transmembrane region of RTN3 competed for, and bound to, the AH2 domain of NS4B, thus abolishing NS4B self-interaction and leading to the downregulation of viral replication. This interaction was mediated by two crucial residues, lysine 52 and tyrosine 63, of AH2, and was regulated by the AH1 domain. The silencing of RTN3 in Huh7 and AVA5 cells harbouring an HCV replicon enhanced the replication of HCV, which was counteracted by the overexpression of recombinant RTN3. The synthesis of viral RNA was also increased in siRNA-transfected human primary hepatocytes infected with HCV derived from cell culture. Our results demonstrated that RTN3 acted as a restriction factor to limit the replication of HCV. PMID:24898729

Wu, Ming-Jhan; Ke, Po-Yuan; Hsu, John T-A; Yeh, Chau-Ting; Horng, Jim-Tong

2014-11-01

360

In vivo dynamics of enterovirus protease revealed by fluorescence resonance emission transfer (FRET) based on a novel FRET pair  

SciTech Connect

An in vivo protease assay suitable for analysis by fluorescence resonance energy transfer (FRET) was developed on the basis of a novel FRET pair. The specifically designed fusion substrate consists of green fluorescent protein 2 (GFP{sup 2})-peptide-red fluorescent protein 2 (DsRed2), with a cleavage motif for the enterovirus 2A protease (2A{sup pro}) embedded within the peptide region. FRET can be readily visualized in real-time from cells expressing the fusion substrate until a proteolytic cleavage by 2A{sup pro} from the input virus. The level of FRET decay is a function of the amount and infection duration of the inoculated virus as measured by a fluorometer assay. The FRET biosensor also responded well to other related enteroviruses but not to a phylogenetically distant virus. Western blot analysis confirmed the physical cleavage of the fusion substrate upon the infections. The study provides proof of principle for applying the FRET technology to diagnostics, screening procedures, and cell biological research.

Hsu, Y.-Y. [Faculty of Biotechnology and Laboratory Science in Medicine, National Yang-Ming University, Taipei, Taiwan (China); Liu, Y.-N. [Faculty of Biotechnology and Laboratory Science in Medicine, National Yang-Ming University, Taipei, Taiwan (China); Wang Wenyen [Incubation Center, National Yang-Ming University, Taipei, Taiwan (China); Kao, Fu-Jen [Institute of Biophotonics, National Yang-Ming University, Taipei, Taiwan (China); Kung, S.-H. [Faculty of Biotechnology and Laboratory Science in Medicine, National Yang-Ming University, Taipei, Taiwan (China)]. E-mail: szkung@ym.edu.tw

2007-02-23

361

CD4 T cell activation by B cells in human Leishmania (Viannia) infection  

PubMed Central

Background An effective adaptive immune response requires activation of specific CD4 T cells. The capacity of B cells to activate CD4 T cells in human cutaneous leishmaniasis caused by Leishmania (Viannia) has not been evaluated. Methods CD4 T cell activation by B cells of cutaneous leishmaniasis patients was evaluated by culture of PBMCs or purified B cells and CD4 T cells with Leishmania panamensis antigens. CD4 T cell and B cell activation markers were evaluated by flow cytometry and 13 cytokines were measured in supernatants with a bead-based capture assay. The effect of Leishmania antigens on BCR-mediated endocytosis of ovalbumin was evaluated in the Ramos human B cell line by targeting the antigen with anti-IgM-biotin and anti-biotin-ovalbumin-FITC. Results Culture of PBMCs from cutaneous leishmaniasis patients with Leishmania antigens resulted in upregulation of the activation markers CD25 and CD69 as well as increased frequency of CD25hiCD127- cells among CD4 T cells. Concomitantly, B cells upregulated the costimulatory molecule CD86. These changes were not observed in PBMCs from healthy subjects, indicating participation of Leishmania-specific lymphocytes expanded in vivo. Purified B cells from these patients, when interacting with purified CD4 T cells and Leishmania antigens, were capable of inducing significant increases in CD25 and CD69 expression and CD25hiCD127- frequency in CD4 T cells. These changes were associated with upregulation of CD86 in B cells. Comparison of changes in CD4 T cell activation parameters between PBMC and B cell/CD4 T cell cultures showed no statistically significant differences; further, significant secretion of IFN-?, TNF-?, IL-6 and IL-13 was induced in both types of cultures. Additionally, culture with Leishmania antigens enhanced BCR-mediated endocytosis of ovalbumin in Ramos human B cells. Conclusions The capacity of B cells specific for Leishmania antigens in peripheral blood of cutaneous leishmaniasis patients to activate CD4 T cells and induce cytokine secretion is similar to that of all cell populations present in PBMCs. This capacity implicates B cells as a plausible target for modulation of the immune response to Leishmania infection as a therapeutic strategy. PMID:24568275

2014-01-01

362

MicroRNA-125b promotes neuronal differentiation in human cells by repressing multiple targets.  

PubMed

MicroRNAs (miRNAs) are a class of small noncoding RNAs that regulate gene expression at the posttranscriptional level. Research on miRNAs has highlighted their importance in neural development, but the specific functions of neurally enriched miRNAs remain poorly understood. We report here the expression profile of miRNAs during neuronal differentiation in the human neuroblastoma cell line SH-SY5Y. Six miRNAs were significantly upregulated during differentiation induced by all-trans-retinoic acid and brain-derived neurotrophic factor. We demonstrated that the ectopic expression of either miR-124a or miR-125b increases the percentage of differentiated SH-SY5Y cells with neurite outgrowth. Subsequently, we focused our functional analysis on miR-125b and demonstrated the important role of this miRNA in both the spontaneous and induced differentiations of SH-SH5Y cells. miR-125b is also upregulated during the differentiation of human neural progenitor ReNcell VM cells, and miR-125b ectopic expression significantly promotes the neurite outgrowth of these cells. To identify the targets of miR-125b regulation, we profiled the global changes in gene expression following miR-125b ectopic expression in SH-SY5Y cells. miR-125b represses 164 genes that contain the seed match sequence of the miRNA and/or that are predicted to be direct targets of miR-125b by conventional methods. Pathway analysis suggests that a subset of miR-125b-repressed targets antagonizes neuronal genes in several neurogenic pathways, thereby mediating the positive effect of miR-125b on neuronal differentiation. We have further validated the binding of miR-125b to the miRNA response elements of 10 selected mRNA targets. Together, we report here for the first time the important role of miR-125b in human neuronal differentiation. PMID:19635812

Le, Minh T N; Xie, Huangming; Zhou, Beiyan; Chia, Poh Hui; Rizk, Pamela; Um, Moonkyoung; Udolph, Gerald; Yang, Henry; Lim, Bing; Lodish, Harvey F

2009-10-01

363

Input files with ORNL—mathematical phantoms of the human body for MCNP-4B  

NASA Astrophysics Data System (ADS)

Protection against ionizing radiation requires information on the absorbed doses in organs of the human body. Implantation of many dosimeters in the human body is undesirable (or impossible), so the doses in organs are not measurable and some kind of dose calculation has to be applied. Calculation of doses in organs requests: (a) an exact description of the geometry of organs, (b) the chemical constitution of tissues, and (c) appropriate computer programs. The first two items, (a) and (b), make a so-called "phantom". In another words, the "phantom of a human body" is a mathematical representation of the human body including all other relevant information. All organs are represented with geometrical bodies (like cylinders, ellipsoids, tori, cones etc.), which are described with suitable mathematical equations. A corresponding chemical constitution for various types of organ tissues is also defined. MCNP-4B ( Monte Carlo N- Particle) is often used as transport code. Users of this software prepare an "input file" providing all necessary information for program execution. This information includes: (a) source definition—type of ionizing radiation, energy spectrum, and geometry of the source; (b) target definition—material constitution, geometry, location in respect to the source etc.; (c) characterization of absorbing media between the source and target; (d) output tally, etc. This paper presents input files with "human phantoms" for the MCNP-4B code. The input files with "phantoms" were prepared based on publications issued by the Oak Ridge National Laboratory (ORNL). Seven input files relating to different age groups (newborn, 1, 5, 10, 15 years, as well as, male and female adults) are presented here. A test example and comparison with other data found in literature are also given. Program summaryTitle of program: INPUT FILES, AMALE, AFEMALE, AGE15, AGE10, AGE5, AGE01, NEWB Catalogue identifier:ADYF_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADYF_v1_0 Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Computer: PC Pentium 3+ Operating systems: Windows 98 Programming language used: Fortran Memory required to execute with typical data: 128 MB No. of lines in distributed program, including test data, etc.: 2879 No. of bytes in distributed program, including test data, etc.: 23 151 Distribution format: tar.gz External subprograms used: The entire code must be linked with the MCNP-4B Nature of problem: The human body and all organs are represented with equations of 3D geometrical bodies. All equations and other relevant data (material composition, densities, etc.) were programmed as input files for MCNP-4B

Krsti?, D.; Nikezi?, D.

2007-01-01

364

IL-7 Dependence in Human B Lymphopoiesis Increases During Progression of Ontogeny from Cord Blood to Bone Marrow1  

PubMed Central

IL-7 is critical for B cell production in adult mice, however its role in human B lymphopoiesis is controversial. One challenge was the inability to differentiate human cord blood (CB) or adult bone marrow (BM) hematopoietic stem cells (HSCs) without murine stroma. Here, we examine the role of IL-7 in human B cell development using a novel, human-only model based on co-culturing human HSCs on primary human BM stroma. In this model, IL-7 increases human B cell production by >60-fold from both CB and adult BM HSCs. IL-7-induced increases are dose-dependent and specific to CD19+ cells. STAT5 phosphorylation and expression of the Ki-67 proliferation antigen, indicate that IL-7 acts directly on CD19+ cells to increase proliferation at the CD34+ and CD34? pro-B cell stages. Without IL-7, HSCS in CB, but not BM give rise to a small but consistent population of CD19LO B lineage cells that express EBF and PAX-5 and respond to subsequent IL-7 stimulation. Flt3 ligand, but not thymic stromal-derived lymhopoietin (TSLP), was required for the IL-7-independent production of human B lineage cells. As compared to CB, adult BM shows a reduction of in vitro generative capacity that is progressively more profound in developmentally sequential populations, resulting in a ~50-fold reduction in IL-7-dependent B lineage generative capacity. These data provide evidence that IL-7 is essential for human B cell production from adult BM and that IL-7-induced expansion of the pro-B compartment is increasingly critical for human B cell production during the progression of ontogeny. PMID:19299724

Parrish, Yasmin Khan; Baez, Ineavely; Milford, Terry-Ann; Benitez, Abigail; Galloway, Nicholas; Rogerio, Jaqueline Willeman; Sahakian, Eva; Kagoda, Mercy; Huang, Grace; Hao, Qian-Lin; Sevilla, Yazmar; Barsky, Lora W.; Zielinska, Ewa; Price, Mary A.; Wall, Nathan R.; Dovat, Sinisa; Payne, Kimberly J.

2009-01-01

365

Genetically engineered mouse models of human B-cell precursor leukemias.  

PubMed

B-cell precursor acute lymphoblastic leukemias (pB-ALLs) are the most frequent type of malignancies of the childhood, and also affect an important proportion of adult patients. In spite of their apparent homogeneity, pB-ALL comprises a group of diseases very different both clinically and pathologically, and with very diverse outcomes as a consequence of their biology, and underlying molecular alterations. Their understanding (as a prerequisite for their cure) will require a sustained multidisciplinary effort from professionals coming from many different fields. Among all the available tools for pB-ALL research, the use of animal models stands, as of today, as the most powerful approach, not only for the understanding of the origin and evolution of the disease, but also for the development of new therapies. In this review we go over the most relevant (historically, technically or biologically) genetically engineered mouse models (GEMMs) of human pB-ALLs that have been generated over the last 20 years. Our final aim is to outline the most relevant guidelines that should be followed to generate an "ideal" animal model that could become a standard for the study of human pB-ALL leukemia, and which could be shared among research groups and drug development companies in order to unify criteria for studies like drug testing, analysis of the influence of environmental risk factors, or studying the role of both low-penetrance mutations and cancer susceptibility alterations. PMID:25486471

Hauer, Julia; Borkhardt, Arndt; Sánchez-García, Isidro; Cobaleda, César

2014-09-15

366

Competitive chemiluminescent enzyme immunoassay for vitamin B12 analysis in human milk.  

PubMed

Recent discoveries of matrix interferences by haptocorrin (HC) in human milk and serum show that past analyses of vitamin B12 in samples with high HC content might have been inaccurate (Lildballe et al., 2009; Carmel & Agrawal, 2012). We evaluated two competitive enzyme-binding immunoassays for serum/plasma (IMMULITE and SimulTRAC-SNB) for B12 analysis in human milk. B12-recovery rates (United States Environmental Protection Agency, 2007) were determined to be 78.9 ± 9.1% with IMMULITE and 225 ± 108% (range 116-553%) using SimulTRAC-SNB, most likely due to the presence of excess HC. HC-interferences were not observed with the IMMULITE assay, rendering previously reported mandatory HC-removal (Lildballe et al., 2009) unnecessary. Linearity continued at low B12-concentrations (24-193 pM; r(2)>0.985). Milk B12 concentrations from Bangladeshi women (72-959 pM) were significantly lower than those from California (154-933 pM; p<0.0001) showing IMMULITE's robustness against the complex milk matrix and its ability to measure low milk B12 concentrations. PMID:24491700

Hampel, Daniela; Shahab-Ferdows, Setareh; Domek, Joseph M; Siddiqua, Towfida; Raqib, Rubhana; Allen, Lindsay H

2014-06-15

367

Small molecule growth inhibitors of human oncogenic gammaherpesvirus infected B-cells.  

PubMed

Epstein-Barr virus (EBV) and Kaposi's sarcoma-associated herpesvirus (KSHV) are two human gammaherpesviruses associated with a broad spectrum of B-cell lymphomas, most acutely in immuno-compromised populations. However, there are no drugs which specifically target KSHV or EBV-associated lymphomas. To identify small molecules which selectively inhibit the growth of EBV or KSHV-associated B-cell lines, we performed a fluorescence based high-throughput screen on multiple stable GFP expressing virus-infected or uninfected B-cell lines. We identified 40 initial compounds with selective growth inhibition and subsequently determined the 50% growth inhibitory concentrations (GI50) for each drug. We further examined compounds with higher specificity to explore the underlying molecular mechanisms using transcription factor analysis, as well as a shRNA based knockdown strategy. Our data identified ten compounds with relatively high efficacy for growth inhibition. Two novel small molecules, NSC#10010 and NSC#65381 were potent growth inhibitors for gammaherpesvirus-associated B-lymphomas through activation of both the NF-?B and c-Myc-mediated signaling pathways. These drugs can serve as potential lead compounds to expand the current therapeutic window against EBV or KSHV-associated human B-cell malignancies. PMID:25306391

Dzeng, Richard K; Jha, Hem Chandra; Lu, Jie; Saha, Abhik; Banerjee, Sagarika; Robertson, Erle S

2015-02-01

368

Expansion and somatic hypermutation of B cell clones in rejected human kidney grafts  

PubMed Central

Background B cell infiltrates are common in rejected kidney allografts, yet their composition is still unclear. The aim of our study was to characterize the clonal composition of B cell infiltrates of rejected human kidney grafts. Methods We used a molecular approach to characterize the partial B cell repertoires of 5 failed human kidney grafts with detectable B cell infiltrates. A comparison between the intragraft and blood repertoire was also conducted for one case. Results Redundant sequences were observed in both blood and graft, although the level of clonal amplification was significantly higher for the graft. Somatic hypermutations (SHM) were also more frequent in sequences found in the graft compared to the blood. The rate of non-silent mutations was significantly higher in complementarity determining regions (CDR) compared to framework regions in blood sequences as well as in graft sequences found at low frequency. In contrast, this preferential distribution was lost in sequences found at high frequency in the graft, suggesting a lack of affinity maturation in situ. Lastly, follicular dendritic cells were undetectable in CD20+ infiltrates in all samples examined. Conclusions We provide here evidence that B cell clones expand and undergo SHM in situ. However, the even distribution of non-silent SHM in high frequency graft sequences together with the absence of FDC do not support the view that infiltrating B cells are part of functional germinal centers. PMID:24825521

Ferdman, Jack; Porcheray, Fabrice; Gao, Baoshan; Moore, Carolina; DeVito, Julie; Dougherty, Sarah; Thomas, Margaret V.; Farkash, Evan A.; Elias, Nahel; Kawai, Tatsuo; Malek, Sayeed K.; Tullius, Stefan G.; Wong, Waichi; Zorn, Emmanuel

2014-01-01

369

Combined Vitamins B12b and C Induce the Glutathione Depletion and the Death of Epidermoid Human Larynx Carcinoma Cells HEp2  

Microsoft Academic Search

The combination of hydroxocobalamin (vitamin B12b) and ascorbicacid (vitamin C) can cause the death of tumor cells at the concentrationsof the components at which they are nontoxic when administeredseparately. This cytotoxic action on epidermoid human larynx carcinomacells HEp-2 in vitro is shown to be due to the hydrogen peroxidegenerated by the combination of vitamins B12b and C. The drop inthe

Vladimir S. Akatov; Yury V. Evtodienko; Violetta V. Leshchenko; Vera V. Teplova; Margarita M. Potselueva; Alexey G. Kruglov; Enric I. Lezhnev; Raisa I. Yakubovskaya

2000-01-01

370

Human Hepatic Stellate Cells Inhibit T cell Response through B7-H1 Pathway  

PubMed Central

Background The liver is an immunological privileged organ – liver allografts are accepted across major histocompatibility complex barriers in many species; however, hepatocyte transplants are acutely rejected, suggesting a role for liver non-parenchymal cells in regulating the immune response. We have shown potent immune regulatory activity of hepatic stellate cells (HSCs) in mice. The aim of this study was to examine the immune regulatory activity of human HSCs. Methods HSCs were isolated from normal human livers for analyses of their impact on T cell response. Results HSCs expressed low HLA-DR and co-stimulatory molecules CD40, CD80, but constitutively expressed high levels of CD54. IFN? stimulated HSCs to express B7-H1 in a dose dependent manner, and produce the suppressive cytokines IL-6, IL-10 and TGF?, but not affect expression of HLA-DR, CD40 and CD80. Human HSCs did not stimulate allogeneic T cell proliferative response, indicating they are not professional APC. HSCs markedly inhibited T cell response elicited by either allogeneic APC or CD3/CD28 beads, which was associated with increases in activated CD4 and CD8 T cell apoptosis. Addition of anti-B7-H1 blocking Ab significantly reversed the inhibitory effect. Conclusions Human HSCs demonstrate potent immune regulatory activity via B7-H1-mediated induction of apoptosis in activated T cells. Understanding of the involved mechanisms may lead to development of novel therapeutic approaches for treatment of liver diseases. PMID:23756770

Charles, Ronald; Chou, Hong-Shiue; Wang, Lianfu; Fung, John J.; Lu, Lina; Qian, Shiguang

2013-01-01

371

Clarithromycin Inhibits NF-?B Activation in Human Peripheral Blood Mononuclear Cells and Pulmonary Epithelial Cells  

PubMed Central

Macrolide antibiotics modulate the production of proinflammatory cytokines in vivo and in vitro. Transcription of the genes for these proinflammatory cytokines is regulated by nuclear factor ?B (NF-?B). We examined whether or not clarithromycin inhibits the activation of NF-?B induced by tumor necrosis factor alpha (TNF-?) or staphylococcal enterotoxin A (SEA) in human monocytic U-937 cells, a T-cell line (Jurkat), a pulmonary epithelial cell line (A549), and peripheral blood mononuclear cells (PBMC). Flow cytometry revealed that clarithromycin suppresses NF-?B activation induced by TNF-? in U-937 and Jurkat cells in a concentration-related manner. Western blot analysis also demonstrated that clarithromycin inhibits NF-?B activation induced by TNF-? in U-937, Jurkat, and A549 cells and PBMC and by SEA in PBMC. Western blot analysis of cytoplasmic extracts of A549 cells revealed that this inhibition is not linked to preservation of expression of the I?B? protein. The chloramphenicol acetyltransferase assay indicated that NF-?B-dependent reporter gene expression is suppressed in U-937 cells pretreated with clarithromycin. These findings are consistent with the idea that clarithromycin suppresses the production of proinflammatory cytokines via inhibition of NF-?B activation. PMID:11120942

Ichiyama, Takashi; Nishikawa, Miki; Yoshitomi, Tomomi; Hasegawa, Shunji; Matsubara, Tomoyo; Hayashi, Takashi; Furukawa, Susumu

2001-01-01

372

Light chain editors of anti-DNA receptors in human B cells  

PubMed Central

Receptor editing is a mechanism of self-tolerance used in newly generated B cells. The expressed heavy (H) or light (L) chain of an autoreactive receptor is replaced by upstream V genes which eliminate or modify autoreactivity. Editing of anti-DNA receptors has been characterized in anti-DNA transgenic mouse models including 3H9, 3H9/56R, and their revertant 3H9GL. Certain L chains, termed editors, rescue anti-DNA B cells by neutralizing or modifying DNA binding of the H chain. This editing mechanism acts on the natural H chain repertoire; endogenous H chains with anti-DNA features are expressed primarily in combination with editor L chains. We ask whether a similar set of L chains exists in the human repertoire, and if so, do they edit H chains with anti-DNA signatures? We compared the protein sequences of mouse editors to all human L chains and found several human L chains similar to mouse editors. These L chains diminish or veto anti-DNA binding when expressed with anti-DNA H chains. The human H chains expressed with these L chains also have relatively high arginine (Arg) content in the H chain complementarity determining region (H3), suggesting that receptor editing plays a role in establishing tolerance to DNA in humans. PMID:24470445

Kalinina, Olga; Wang, Yue; Sia, Kevin; Radic, Marko; Cazenave, Pierre-André

2014-01-01

373

A case of pure red cell aplasia and systemic lupus erythematosus caused by human parvovirus B19 infection  

Microsoft Academic Search

Human parvovirus B19 (B19) rarely induces pure red cell aplasia (PRCA) in healthy hosts. Meanwhile B19 infection is often\\u000a clinically similar to systemic lupus erythematosus (SLE), and several cases have been reported wherein B19 actually stimulated\\u000a SLE exacerbation in an immunocompetent subject. An 82-year-old healthy woman was diagnosed to have complicated with B19 infection\\u000a and PRCA. Four weeks later, she

Haruko Ideguchi; Shigeru Ohno; Yoshiaki Ishigatsubo

2007-01-01

374

Molecular Insights into Human Monoamine Oxidase B Inhibition by the Glitazone Antidiabetes Drugs  

PubMed Central

The widely employed antidiabetic drug pioglitazone (Actos) is shown to be a specific and reversible inhibitor of human monoamine oxidase B (MAO B). The crystal structure of the enzyme–inhibitor complex shows that the R-enantiomer is bound with the thiazolidinedione ring near the flavin. The molecule occupies both substrate and entrance cavities of the active site, establishing noncovalent interactions with the surrounding amino acids. These binding properties differentiate pioglitazone from the clinically used MAO inhibitors, which act through covalent inhibition mechanisms and do not exhibit a high degree of MAO A versus B selectivity. Rosiglitazone (Avandia) and troglitazone, other members of the glitazone class, are less selective in that they are weaker inhibitors of both MAO A and MAO B. These results suggest that pioglitazone may have utility as a “repurposed” neuroprotectant drug in retarding the progression of disease in Parkinson's patients. They also provide new insights for the development of reversible isoenzyme-specific MAO inhibitors. PMID:22282722

2011-01-01

375

Global modulation of cellular transcription by human cytomegalovirus is initiated by viral glycoprotein B  

PubMed Central

Human cytomegalovirus (HCMV) infection alters the expression of many cellular genes, including IFN-stimulated genes (ISGs) [Zhu, H., Cong, J.-P., Mamtora, G., Gingeras, T. & Shenk, T. (1998) Proc. Natl. Acad. Sci. USA 95, 14470–14475]. By using high-density cDNA microarrays, we show that the HCMV-regulated gene expression profile in fibroblasts does not differ substantially from the response generated by IFN. Furthermore, we identified the specific viral component triggering this response as the envelope glycoprotein B (gB). Cells treated with gB, but not other herpesviral glycoproteins, exhibited the same transcriptional profile as HCMV-infected cells. Thus, the interaction of gB with its as yet unidentified cellular receptor is the principal mechanism by which HCMV alters cellular gene expression early during infection. These findings highlight a pioneering paradigm for the consequences of virus–receptor interactions. PMID:11390970

Simmen, Kenneth A.; Singh, Jasbir; Luukkonen, B. G. Mattias; Lopper, Matt; Bittner, Anton; Miller, Nancy E.; Jackson, Michael R.; Compton, Teresa; Früh, Klaus

2001-01-01

376

Bog blueberry anthocyanins alleviate photoaging in ultraviolet-B irradiation-induced human dermal fibroblasts.  

PubMed

Fruits of bog blueberry (Vaccinium uliginosum L.) are rich in anthocyanins that contribute pigmentation. Anthocyanins have received much attention as agents with potentials preventing chronic diseases. This study investigated the capacity of anthocyanin-rich extract from bog blueberry (ATH-BBe) to inhibit photoaging in UV-B-irradiated human dermal fibroblasts. BBe anthocyanins were detected as cyanidin-3-glucoside, petunidin-3-glucoside, malvidin-3-glucoside, and delphinidin3-glucoside. ATH-BBe attenuated UV-B-induced toxicity accompanying reactive oxygen species (ROS) production and the resultant DNA damage responsible for activation of p53 and Bad. Preincubation of ATH-BBe markedly suppressed collagen degradation via blunting production of collagenolytic matrix metalloproteinases (MMP). Additionally, ATH-BBe enhanced UV-B-downregulated procollagen expression at transcriptional levels. We next attempted to explore whether ATH-BBe mitigated the MMP-promoted collagen degradation through blocking nuclear factor kappaB (NF-kappaB) activation and MAPK-signaling cascades. UV-B radiation enhanced nuclear translocation of NF-kappaB, which was reversed by treatment with ATH-BBe. The UV-B irradiation rapidly activated apoptosis signal-regulating kinase-1 (ASK-1)-signaling cascades of JNK and p38 mitogen-activated protein kinase (p38 MAPK), whereas ATH-BBe hampered phosphorylation of c-Jun, p53, and signal transducers and activators of transcription-1 (STAT-1) linked to these MAPK signaling pathways. ATH-BBe diminished UV-B augmented-release of inflammatory interleukin (IL)-6 and IL-8. These results demonstrate that ATH-BBe dampens UV-B-triggered collagen destruction and inflammatory responses through modulating NF-kappaB-responsive and MAPK-dependent pathways. Therefore, anthocyanins from edible bog blueberry may be protective against UV-induced skin photoaging. PMID:19199288

Bae, Ji-Young; Lim, Soon Sung; Kim, Sun Ju; Choi, Jung-Suk; Park, Jinseu; Ju, Sung Mi; Han, Seoung Jun; Kang, Il-Jun; Kang, Young-Hee

2009-06-01

377

Strong Inverse Correlation Between MicroRNA-125b and Human Papillomavirus DNA in Productive Infection  

PubMed Central

Infection by the human papillomavirus (HPV) is a cause of cervical intraepithelial neoplasia (CIN) and cancer. microRNA (miRNA) in situ analysis of the transformation zone epithelia, the site of initial cervical HPV infection, showed that miRNAs let-7c, — 99a, 26a, and 125b were the most abundantly expressed. In situ testing of CIN 1 showed a dramatic reduction in miR-125b expression in the koilocytes, the cytologic marker of productive HPV infection. A marked reduction in miR-125b was likewise observed in the HPV-infected cells of the condyloma acuminatum, verruca vulgaris, and epidermodysplasia verruciformis. Reverse transcriptase in situ polymerase chain reaction (PCR) showed that the pre-miRNA 125b was present in the koilocyte, suggesting direct inactivation of the mature miRNA. HEK cells transfected with only the antimiR-125b showed perinuclear halos equivalent to HPV-infected koilocytes. NIH 3T3 cells transfected with the HPV 16 full-length genome and mimetic miR-125b showed a marked reduction in viral DNA and protein synthesis by quantitative PCR and in situ-based analyses, respectively (P=0.002). Alternatively, cotransfection with anti-miR-125b and HPV 16 markedly increased HPV DNA (P=0.002). Sequence analyses showed strong homology between L2 of different HPV genotypes and miR-125b. Transfection with HPV 16 L2 resulted in a marked reduction in miR-125b levels in the NIH 3T3 cells. HPV L2-induced inactivation of miR-125b is associated with the classic cytologic changes of the koilocyte, and the exogenous application of mimetic miR-125b markedly inhibits HPV DNA synthesis. PMID:20736742

Nuovo, Gerard J.; Wu, Xin; Volinia, Stefano; Yan, Fengting; di Leva, Gianpiero; Chin, Nena; Nicol, Alcina F.; Jiang, Jinmai; Otterson, Gregory; Schmittgen, Thomas D.; Croce, Carlo

2014-01-01

378

Characterization of cells of the B lineage in the human adult greater omentum  

PubMed Central

Peritoneal B cells and their omental precursors play an important role in the immune response of the peritoneal cavity and mucosal surfaces in mice. We have previously shown that peritoneal and mucosal B lineage cells are unlikely to be significantly linked in humans. However, the status of the omentum remains unknown. Here, using immunohistochemistry, we observed that sparse, quiescent B cells and occasional clusters of B cells were present in the omentum and that plasma cells, predominantly with cytoplasmic immunoglobulin G (IgG), were present. We analysed sequences of immunoglobulin genes amplified using reverse transcriptase–polymerase chain reaction (RT-PCR) from the normal human greater omentum, and describe the characteristics of variable region genes used by IgG, IgA and IgM. We focused on the properties of IgVH4 and IgVH5 families to allow comparisons of like with like between different Ig isotypes and cells from different immune compartments. We observed that the IgM genes were derived from a mixed population with mutated and unmutated immunoglobulin sequences. All IgVH4 and IgVH5 genes used by IgA and IgG from omental cells showed evidence of somatic hypermutation but the load of mutations was not significantly different to that seen in either the systemic or the mucosal compartments. The trends observed, including the dominance of IgG plasma cells, the IgA1/IgA2 ratio being biased towards IgA1, JH1 usage, and a moderate level of somatic mutations, link omental B lineage cells with the systemic compartment. These observations reinforce previous studies highlighting the difference between human and murine B-cell compartments and their relationship to the mucosal immune system. PMID:16787506

Boursier, Laurent; Montalto, Stephen Attard; Raju, Shanti; Culora, Giuseppe; Spencer, Jo

2006-01-01

379

Epithelial cells modulate genes associated with NF kappa B activation in co-cultured human macrophages.  

PubMed

Macrophages located in airways and the alveolar space are continually exposed to different signals from the respiratory mucosa. In this respect, epithelial cells represent an important source of cytokines and mediators modulating the state of activation and/or differentiation of mononuclear phagocytes. Many of the proinflammatory genes induced in macrophages during immune and immunopathological reactions are regulated by transcription factor NF kappa B. The aim of our study was to characterize changes in the expression of genes associated with NF kappa B activation and signalling in THP-1 human macrophages co-cultured with A549 respiratory epithelial cells. At least 4-fold upregulation of mRNA level was found in 29 of 84 tested genes including genes for multiple cytokines and chemokines, membrane antigens and receptors, and molecules associated with NF kappa B signalling. The mRNA induction was confirmed at the level of protein expression by evaluating the release of IL-6 and IL-8 and by ICAM-1 expression. Blocking of one NF?B subunit by p65 siRNA inhibited the production of IL-6 in both cell types while IL-8 release from THP-1 cells did not seem to be affected. We conclude from our data that unstimulated respiratory epithelial cells regulate genes associated with NF kappa B dependent immune responses in human macrophages and that these interactions may play a key role in immediate responses in the respiratory mucosa. PMID:21601940

Striz, I; Brabcova, E; Kolesar, L; Liu, X D; Brabcova, I; Sekerkova, A; Poole, J A; Jaresova, M; Slavcev, A; Rennard, S I

2011-10-01

380

Structural and Thermodynamic Basis of (+)-?-Pinene Binding to Human Cytochrome P450 2B6  

PubMed Central

Despite recent advances in atomic level understanding of drug and inhibitor interactions with human cytochromes P450, the decades-old questions of chemical and structural determinants of hydrocarbon binding are still unanswered. (+)-?-Pinene is a monoterpene hydrocarbon that is widely distributed in the environment and a potent P450 2B inhibitor. Therefore, a combined biophysical and structural analysis of human P450 2B6 interactions with (+)-?-pinene was undertaken to elucidate the basis of the very high affinity binding. Binding of (+)-?-pinene to the P450 active site was demonstrated by a Type I spectral shift. Thermodynamics of ligand binding were explored using isothermal titration calorimetry and compared to those of P450 2A6, which is much less flexible than 2B6 based on comparison of multiple X-ray crystal structures. Consistent with expectation, entropy is the major driving force for hydrocarbon binding to P450 2A6, as evidenced by the calorimetric results. However, formation of the 2B6-(+)-?-pinene complex has a significant enthalpic component. A 2.0 Å resolution crystal structure of this enzyme ligand complex reveals that the highly plastic 2B6 utilizes previously unrecognized rearrangements of protein motifs. The results indicate that the specific components of enthalpic contribution to ligand binding are closely tied to the degree of enzyme flexibility. PMID:23786449

Wilderman, P. Ross; Shah, Manish B.; Jang, Hyun-Hee; Stout, C. David; Halpert, James R.

2013-01-01

381

Agriculture facilitated permanent human occupation of the Tibetan Plateau after 3600 B.P.  

PubMed

Our understanding of when and how humans adapted to living on the Tibetan Plateau at altitudes above 2000 to 3000 meters has been constrained by a paucity of archaeological data. Here we report data sets from the northeastern Tibetan Plateau indicating that the first villages were established only by 5200 calendar years before the present (cal yr B.P.). Using these data, we tested the hypothesis that a novel agropastoral economy facilitated year-round living at higher altitudes since 3600 cal yr B.P. This successful subsistence strategy facilitated the adaptation of farmers-herders to the challenges of global temperature decline during the late Holocene. PMID:25593179

Chen, F H; Dong, G H; Zhang, D J; Liu, X Y; Jia, X; An, C B; Ma, M M; Xie, Y W; Barton, L; Ren, X Y; Zhao, Z J; Wu, X H; Jones, M K

2015-01-16

382

Detection of Tissue Kallikrein and Kinn B1 and B2 Receptor mRNAs in Human Brain by In Situ RT-PCR  

Microsoft Academic Search

Tissue kallikrein (TK) and kinin receptors have been immuno-localized in various areas of the human nervous system, suggesting that the kallikrein-kinin system (KKS) may be functionally active in the brain. The aim of this study was to determine the cellular expression of TK and kinin B1 and B2 receptor mRNAs in specific regions of the human brain by in situ

R. Mahabeer; S. Naidoo; D. M. Raidoo

2000-01-01

383

Mechanisms of Interleukin 1 b Induced Human Airway Smooth Muscle Hyporesponsiveness to Histamine Involvement of p38 MAPK and NF k B  

Microsoft Academic Search

We have investigated the effect of IL-1 b on histamine H 1 -receptor (H 1 R)-mediated inositol phosphate (IP) accumulation in human airway smooth muscle cells (HASMC) and on histamine-induced contraction of human bronchial rings. Stimulation of HASMC for 24 h with IL-1 b resulted in significant loss of histamine-induced IP formation, which was associated with a reduction of histamine-

JAN L. PYPE; HAIYAN XU; MARLEEN SCHUERMANS; LIEVEN J. DUPONT; WIM WUYTS; JUDITH C. W. MAK; PETER J. BARNES; MAURITS G. DEMEDTS; GEERT M. VERLEDEN

384

Overexpression of a splice variant of DNA methyltransferase 3b, DNMT3b4, associated with DNA hypomethylation on pericentromeric satellite regions during human hepatocarcinogenesis  

Microsoft Academic Search

DNA hypomethylation on pericentromeric satellite regions is an early and frequent event associated with heterochromatin instability during human hepatocarcinogenesis. A DNA methyltransferase, DNMT3b, is required for methylation on pericentromeric satellite regions during mouse development. To clarify the molecular mechanism underlying DNA hypomethylation on pericentromeric satellite regions during human hepatocarcinogenesis, we examined mutations of the DNMT3b gene and mRNA expression levels

Yoshimasa Saito; Yae Kanai; Michiie Sakamoto; Hidetsugu Saito; Hiromasa Ishii; Setsuo Hirohashi

2002-01-01

385

Inhibition of human immunodeficiency virus type 1 replication by blocking IkappaB kinase with noraristeromycin.  

PubMed

Nuclear factor kappaB (NF-kappaB) is one of the critical transcription factors in inflammatory responses and replication of viruses such as human immunodeficiency virus (HIV). In fact, it has been demonstrated that various NF-kappaB inhibitors could block HIV replication. To explore more potent NF-kappaB inhibitors, we focused on carbocyclic adenine nucleosides that had been reported to have anti-inflammatory effects. We synthesized 15 carbocyclic adenine nucleoside compounds and examined their effects on the NF-kappaB-dependent gene expression using HEK293 cell line. Among these compounds, noraristeromycin (NAM) exhibited the most potent inhibitory effect on the NF-kappaB activity under the non-cytotoxic concentrations. NAM-inhibited IkappaBalpha phosphorylation and degradation upon stimulation of cells with tumour necrosis factor-alpha (TNF-alpha). In addition, NAM prevented p65 phoshorylation. These findings suggested that both IkappaB kinase-alpha (IKK-alpha) and -beta were targeted by NAM. Interestingly, in vitro kinase assay revealed that NAM inhibited the kinase activity of IKK-alpha more potently than that of IKK-beta. When we treated the cell lines, OM10.1 and Molt4/IIIB, in which HIV-1 is latently and chronically infected, we found a strong suppressive effect of NAM on HIV-1 viral replication upon stimulation with TNF-alpha. PMID:18713798

Asamitsu, Kaori; Yamaguchi, Tsuyoshi; Nakata, Kenji; Hibi, Yurina; Victoriano, Ann-Florence B; Imai, Kenichi; Onozaki, Kikuo; Kitade, Yukio; Okamoto, Takashi

2008-11-01

386

Apigenin inhibits enterovirus-71 infection by disrupting viral RNA association with trans-acting factors.  

PubMed

Flavonoids are widely distributed natural products with broad biological activities. Apigenin is a dietary flavonoid that has recently been demonstrated to interact with heterogeneous nuclear ribonucleoproteins (hnRNPs) and interferes with their RNA editing activity. We investigated whether apigenin possessed antiviral activity against enterovirus-71 (EV71) infection since EV71 infection requires of hnRNP proteins. We found that apigenin selectively blocks EV71 infection by disrupting viral RNA association with hnRNP A1 and A2 proteins. The estimated EC50 value for apigenin to block EV71 infection was determined at 10.3 µM, while the CC50 was estimated at 79.0 µM. The anti-EV71 activity was selective since no activity was detected against several DNA and RNA viruses. Although flavonoids in general share similar structural features, apigenin and kaempferol were among tested compounds with significant activity against EV71 infection. hnRNP proteins function as trans-acting factors regulating EV71 translation. We found that apigenin treatment did not affect EV71-induced nucleocytoplasmic redistribution of hnRNP A1 and A2 proteins. Instead, it prevented EV71 RNA association with hnRNP A1 and A2 proteins. Accordingly, suppression of hnRNP A1 and A2 expression markedly reduced EV71 infection. As a positive sense, single strand RNA virus, EV71 has a type I internal ribosome entry site (IRES) that cooperates with host factors and regulates EV71 translation. The effect of apigenin on EV71 infection was further demonstrated using a bicistronic vector that has the expression of a GFP protein under the control of EV71 5'-UTR. We found that apigenin treatment selectively suppressed the expression of GFP, but not a control gene. In addition to identification of apigenin as an antiviral agent against EV71 infection, this study also exemplifies the significance in antiviral agent discovery by targeting host factors essential for viral replication. PMID:25330384

Zhang, Wei; Qiao, Haishi; Lv, Yuanzi; Wang, Jingjing; Chen, Xiaoqing; Hou, Yayi; Tan, Renxiang; Li, Erguang

2014-01-01

387

Human liver chimeric mice provide a model for hepatitis B and C virus infection and treatment  

PubMed Central

A paucity of versatile small animal models of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection has been an impediment to both furthering understanding of virus biology and testing antiviral therapies. We recently described a regulatable system for repopulating the liver of immunodeficient mice (specifically mice lacking fumaryl acetoacetate hydrolase [Fah], recombination activating gene 2 [Rag2], and the ?-chain of the receptor for IL-2 [Il-2r?]) with human hepatocytes. Here we have shown that a high transplantation dose (3 × 106 to 5 × 106 human hepatocytes/mouse) generates a higher rate of liver chimerism than was previously obtained in these mice, up to 95% human hepatocyte chimerism. Mice with a high level of human liver chimerism propagated both HBV and HCV, and the HCV-infected mice were responsive to antiviral treatment. This human liver chimeric mouse model will expand the experimental possibilities for studying HBV and HCV infection, and possibly other human hepatotropic pathogens, and prove useful for antiviral drug testing. PMID:20179355

Bissig, Karl-Dimiter; Wieland, Stefan F.; Tran, Phu; Isogawa, Masanori; Le, Tam T.; Chisari, Francis V.; Verma, Inder M.

2010-01-01

388

Site-Directed Mutagenesis of Human Cytosolic Sulfotransferase (SULT) 2B1b to Phospho-mimetic Ser348Asp Results in an Isoform With Increased Catalytic Activity  

PubMed Central

Human SULT2B1b is distinct from other SULT isoforms due to the presence of unique amino (N)- and carboxy (C)-terminal peptides. Using site-directed mutagenesis, it was determined that phosphorylation of Ser348 was associated with nuclear localization. To investigate the effects of this phosphorylation of Ser348 on activity and cellular localization, an in silico molecular mimic was generated by mutating Ser348 to an Asp. The Asp residue mimics the shape and charge of a phospho-Ser and homology models of SULT2B1b-phospho-S348 and SULT2B1b-S348D suggest a similar significant structural rearrangement in the C-terminal peptide. To evaluate the functional consequences of this post-translational modification and predicted rearrangement, 6His-SULT2B1b-S348D was synthesized, expressed, purified and characterized. The 6His-SULT2B1b-S348D has a specific activity for DHEA sulfation ten-fold higher than recombinant 6His-SULT2B1b (209.6 and 21.8 pmol·min?1·mg?1, respectively). Similar to native SULT2B1b, gel filtration chromatography showed SULT2B1b-S348D was enzymatically active as a homodimer. Stability assays comparing SULT2B1b and SUL2B1b-S348 demonstrated that SULT2B1b is 60% less thermostable than SULT2B1b-348D. The increased stability and sulfation activity allowed for better characterization of the sulfation kinetics for putative substrates as well as the determination of dissociation constants that were difficult to obtain with wild-type (WT) 6His-SULT2B1b. The KDs for DHEA and PAPS binding to 6His-SULT2B1b-S348D were 650 ± 7 nM and 265 ± 4 nM, respectively, whereas KDs for binding of substrates to the WT enzyme could not be determined. Characterization of the molecular mimic SULT2B1b-S348D provides a better understanding for the role of the unique structure of SULT2B1b and its effect on sulfation activity, and has allowed for improved kinetic characterization of the SULT2B1b enzyme. PMID:21855633

Salman, Emily D.; He, Dongning; Runge-Morris, Melissa; Kocarek, Thomas A.; Falany, Charles N.

2011-01-01

389

FOXP1 directly represses transcription of proapoptotic genes and cooperates with NF-?B to promote survival of human B cells  

PubMed Central

The forkhead transcription factor FOXP1 is involved in B-cell development and function and is generally regarded as an oncogene in activated B-cell–like subtype of diffuse large B-cell lymphoma (DLBCL) and mucosa-associated lymphoid tissue lymphoma, lymphomas relying on constitutive nuclear factor ?B (NF-?B) activity for survival. However, the mechanism underlying its putative oncogenic activity has not been established. By gene expression microarray, upon overexpression or silencing of FOXP1 in primary human B cells and DLBCL cell lines, combined with chromatin immunoprecipitation followed by next-generation sequencing, we established that FOXP1 directly represses a set of 7 proapoptotic genes. Low expression of these genes, encoding the BH3-only proteins BIK and Harakiri, the p53-regulatory proteins TP63, RASSF6, and TP53INP1, and AIM2 and EAF2, is associated with poor survival in DLBCL patients. In line with these findings, we demonstrated that FOXP1 promotes the expansion of primary mature human B cells by inhibiting caspase-dependent apoptosis, without affecting B-cell proliferation. Furthermore, FOXP1 is dependent upon, and cooperates with, NF-?B signaling to promote B-cell expansion and survival. Taken together, our data indicate that, through direct repression of proapoptotic genes, (aberrant) expression of FOXP1 complements (constitutive) NF-?B activity to promote B-cell survival and can thereby contribute to B-cell homeostasis and lymphomagenesis. PMID:25267198

van Keimpema, Martine; Grüneberg, Leonie J.; Mokry, Michal; van Boxtel, Ruben; Koster, Jan; Coffer, Paul J.; Pals, Steven T.

2014-01-01

390

FOXP1 directly represses transcription of proapoptotic genes and cooperates with NF-?B to promote survival of human B cells.  

PubMed

The forkhead transcription factor FOXP1 is involved in B-cell development and function and is generally regarded as an oncogene in activated B-cell-like subtype of diffuse large B-cell lymphoma (DLBCL) and mucosa-associated lymphoid tissue lymphoma, lymphomas relying on constitutive nuclear factor ?B (NF-?B) activity for survival. However, the mechanism underlying its putative oncogenic activity has not been established. By gene expression microarray, upon overexpression or silencing of FOXP1 in primary human B cells and DLBCL cell lines, combined with chromatin immunoprecipitation followed by next-generation sequencing, we established that FOXP1 directly represses a set of 7 proapoptotic genes. Low expression of these genes, encoding the BH3-only proteins BIK and Harakiri, the p53-regulatory proteins TP63, RASSF6, and TP53INP1, and AIM2 and EAF2, is associated with poor survival in DLBCL patients. In line with these findings, we demonstrated that FOXP1 promotes the expansion of primary mature human B cells by inhibiting caspase-dependent apoptosis, without affecting B-cell proliferation. Furthermore, FOXP1 is dependent upon, and cooperates with, NF-?B signaling to promote B-cell expansion and survival. Taken together, our data indicate that, through direct repression of proapoptotic genes, (aberrant) expression of FOXP1 complements (constitutive) NF-?B activity to promote B-cell survival and can thereby contribute to B-cell homeostasis and lymphomagenesis. PMID:25267198

van Keimpema, Martine; Grüneberg, Leonie J; Mokry, Michal; van Boxtel, Ruben; Koster, Jan; Coffer, Paul J; Pals, Steven T; Spaargaren, Marcel

2014-11-27

391

Intracellular Sites for Storage and Recycling of C3b Receptors in Human Neutrophils  

Microsoft Academic Search

Upon activation of human neutrophils, C3b receptors (type 1 complement receptors, CR1) are rapidly translocated from an intracellular pool to the surface, increasing plasma membrane expression 6- to 10-fold. This is followed by reinternalization and degradation of the receptors, even in the absence of ligand. Upregulation of surface CR1 may occur without exocytosis of primary or secondary granules, and intracellular

Melvin Berger; Erica M. Wetzler; Elisabeth Welter; Jerrold R. Turner; Alan M. Tartakoff

1991-01-01

392

bFGF is the putative natural growth factor for human melanocytes  

Microsoft Academic Search

Summary  Normal human melanocytes, unlike pigment cells from metastatic melanomas, do not survive in culture in routine, serum-supplemented\\u000a media. The search for natural growth factors for melanocytes has shown that mitogenic activity is ubiquitous in several tissues\\u000a and in melanomas. Of several known growth factors tested, basic fibroblast growth factor (bFGF) was the only one mitogenic\\u000a for melanocytes but only in

Ruth Halaban; Sikha Ghosh; Andrew Baird

1987-01-01

393

Quantitative tritium exchange of (³H) aflatoxin B1 during penetration through isolated human skin  

Microsoft Academic Search

Tritium labelled aflatoxin B1 ((G-³H)AFB1) underwent an almost total tritium exchange with water during penetration through isolated human skin. The process was not enzymatic and the site of exchange appeared to be within the epidermis. The mechanism which mediated this extensive exchange was not determined. However, the tritium in (G-³H)AFB1 was found to be very susceptible to chemical conditions which

R. T. Riley; B. W. Kemppainen; W. P. Norred

1988-01-01

394

Human Cytomegalovirus Inhibitor AL18 Also Possesses Activity against Influenza A and B Viruses  

PubMed Central

AL18, an inhibitor of human cytomegalovirus DNA polymerase, was serendipitously found to also block the interaction between the PB1 and PA polymerase subunits of influenza A virus. Furthermore, AL18 effectively inhibited influenza A virus polymerase activity and the overall replication of influenza A and B viruses. A molecular model to explain the binding of AL18 to both cytomegalovirus and influenza targets is proposed. Thus, AL18 represents an interesting lead for the development of new antivirals. PMID:22908168

Muratore, Giulia; Mercorelli, Beatrice; Goracci, Laura; Cruciani, Gabriele; Digard, Paul

2012-01-01

395

Modulation of drug-induced apoptosis in a human B-lymphoma cell line (HT58)  

Microsoft Academic Search

The cytotoxic effect of etoposide (ETO), a topoisomerase II inhibitor, and staurosporine (STA), a non-selective protein kinase inhibitor, were studied on a human lymphoma cell line of B-cell origin (HT58). Apoptosis, induced dose dependently by both drugs, was accompanied with nucleosomal DNA fragmentation detected by flow cytometry. On the other hand, induction of cell death failed using phorbol ester (PMA),

Rudolf Mihalik; László Kopper; Miklós Benczúr

1995-01-01

396

High throughput Screening to Identify Natural Human Monoamine Oxidase B Inhibitors  

PubMed Central

Age-related increase in monoamine oxidase B (MAO-B) may contribute to CNS neurodegenerative diseases. Moreover, MAO-B inhibitors are used in the treatment of idiopathic Parkinson disease as preliminary monotherapy or adjunct therapy with L-dopa. To date, meager natural sources of MAO-B inhibitors have been identified, and the relative strength, potency and rank of many plants relative to standard drugs such as Selegiline (L-deprenyl, Eldepryl) are not known. In this work, we developed and utilized a high throughput enzyme microarray format to screen and evaluate 905 natural product extracts (0.025–.7 mg/ml) to inhibit human MAO-B derived from BTI-TN-5B1-4 cells infected with recombinant baculovirus. The protein sequence of purified enzyme was confirmed using 1D gel electrophoresis-matrix assisted laser desorption ionization-time-of-flight-tandem mass spectroscopy, and enzyme activity was confirmed by [1] substrate conversion (3-mM benzylamine) to H202 and [2] benzaldehyde. Of the 905 natural extracts tested, the lowest IC50s [<0.07 mg/ml] were obtained with extracts of Amur Corktree (Phellodendron amurense), Bakuchi Seed(Cyamopsis psoralioides), Licorice Root (Glycyrrhiza glabra/uralensis), Babchi (Psoralea corylifolia seed). The data also show, albeit to a lesser extent, inhibitory properties of herbs originating from the mint family (Lamiaceae) and Turmeric, Comfrey, Bringraj, Skullcap, Kava-kava, Wild Indigo, Gentian and Green Tea. In conclusion, the data reflect relative potency information by rank of commonly used herbs and plants that contain human MAO-B inhibitory properties in their natural form. PMID:22887993

Mazzio, E; Deiab, S; Park, K; Soliman, KFA

2012-01-01

397

Interaction of Epstein-Barr virus (EBV) with human B-lymphocytes  

SciTech Connect

Epstein-Barr virus, EBV, and humans have a common history that reaches back to our primate ancestors. The virus co-evolved with man and has established a largely harmless and highly complex co-existence. It is carried as silent infection by almost all human adults. A serendipitous discovery established that it is the causative agent of infectious mononucleosis. Still, EBV became known first in 1964, in a rare, geographically prevalent malignant lymphoma of B-cell origin, Burkitt lymphoma BL. Its association with a malignancy prompted intensive studies and its capacity to immortalize B-lymphocytes in vitro was soon demonstrated. Consequently EBV was classified therefore as a potentially tumorigenic virus. Despite of this property however, the virus carrier state itself does not lead to malignancies because the transformed cells are recognized by the immune response. Consequently the EBV induced proliferation of EBV carrying B-lymphocytes is manifested only under immunosuppressive conditions. The expression of EBV encoded genes is regulated by the cell phenotype. The virus genome can be found in malignancies originating from cell types other than the B-lymphocyte. Even in the EBV infected B-cell, the direct transforming capacity is restricted to a defined window of differentiation. A complex interaction between virally encoded proteins and B-cell specific cellular proteins constitute the proliferation inducing program. In this short review we touch upon aspects which are the subject of our present work. We describe the mechanisms of some of the functional interactions between EBV encoded and cellular proteins that determine the phenotype of latently infected B-cells. The growth promoting EBV encoded genes are not expressed in the virus carrying BL cells. Still, EBV seems to contribute to the etiology of this tumor by modifying events that influence cell survival and proli