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evolving the lock to fit the key to create a family of g protein-coupled receptors potently activated by an inert ligand.we evolved muscarinic receptors in yeast to generate a family of g protein-coupled receptors (gpcrs) that are activated solely by a pharmacologically inert drug-like and bioavailable compound (clozapine-n-oxide). subsequent screening in human cell lines facilitated the creation of a family of muscarinic acetylcholine gpcrs suitable for in vitro and in situ studies. we subsequently created lines of telomerase-immortalized human pulmonary artery smooth muscle cells stably expressing all five famil ...200717360345
panmicrobial oligonucleotide array for diagnosis of infectious diseases.to facilitate rapid, unbiased, differential diagnosis of infectious diseases, we designed greenechippm, a panmicrobial microarray comprising 29,455 sixty-mer oligonucleotide probes for vertebrate viruses, bacteria, fungi, and parasites. methods for nucleic acid preparation, random primed pcr amplification, and labeling were optimized to allow the sensitivity required for application with nucleic acid extracted from clinical materials and cultured isolates. analysis of nasopharyngeal aspirates, b ...200717370518
insertion of egfp into the replicase gene of semliki forest virus results in a novel, genetically stable marker virus.alphavirus-based vector and replicon systems have been extensively used experimentally and are likely to be used in human and animal medicine. whilst marker genes can be inserted easily under the control of a duplicated subgenomic promoter, these constructs are often genetically unstable. here, a novel alphavirus construct is described in which an enhanced green fluorescent protein (egfp) marker gene is inserted into the virus replicase open reading frame between nsp3 and nsp4, flanked by nsp2 p ...200717374766
synergistic roles of antibody and interferon in noncytolytic clearance of sindbis virus from different regions of the central nervous system.sindbis virus (sinv) is an alphavirus that causes infection of neurons and encephalomyelitis in adult immunocompetent mice. recovery can occur without apparent neurological damage. to better define the factors facilitating noncytolytic clearance of sinv in different regions of the central nervous system (cns) and the roles of innate and adaptive immune responses at different times during infection, we have characterized sinv infection and clearance in the brain, brain stem, and spinal cords of s ...200717376910
structure of immature west nile virus.the structure of immature west nile virus particles, propagated in the presence of ammonium chloride to block virus maturation in the low-ph environment of the trans-golgi network, was determined by cryo-electron microscopy (cryo-em). the structure of these particles was similar to that of immature west nile virus particles found as a minor component of mature virus samples (naturally occurring immature particles [noips]). the structures of mature infectious flaviviruses are radically different ...200717376919
ubp43 gene expression is required for normal isg15 expression and fetal development.isg15 covalently modifies murine endometrial proteins in response to early pregnancy. isg15 can also be severed from targeted proteins by a specific protease called ubp43 (usp18). mice lacking ubp43 (null) form increased conjugated isg15 in response to interferon. the isg15 system has not been examined in chorioallantoic placenta (cp) or mesometrial (mm) components of implantation sites beyond 9.5 days post coitum (dpc). it was hypothesized that deletion of ubp43 would cause disregulation of isg ...200717381847
homer 1a uncouples metabotropic glutamate receptor 5 from postsynaptic effectors.metabotropic glutamate receptors (mglurs) and homer proteins play critical roles in neuronal functions including plasticity, nociception, epilepsy, and drug addiction. furthermore, homer proteins regulate mglur1/5 function by acting as adapters and facilitating coupling to effectors such as the inositol triphosphate receptor. however, although homer proteins and their interaction with mglurs have been the subject of intense study, direct measurements of homer-induced changes in postsynaptic mglu ...200717389377
viral vector-induced amygdala npy overexpression reverses increased alcohol intake caused by repeated deprivations in wistar rats.acute administration of neuropeptide y (npy) modulates alcohol intake in genetic and chemical models of high intake, while leaving intake unaffected during 'normal' or baseline conditions. in non-selected, normal rat lines, alcohol consumption can be increased by prolonged exposure to alcohol, and it is unclear what effect a constitutive increase in npy function will have on alcohol intake. the purpose of the present study was to examine the effects on alcohol intake of an inducible, constitutiv ...200717405766
therapy with minocycline aggravates experimental rabies in mice.minocycline is a tetracycline derivative with antiapoptotic and anti-inflammatory properties, and the drug has been shown to have beneficial effects in a variety of models of neurological disorders. the potentially neuroprotective role of minocycline was assessed in experimental in vitro and in vivo models of rabies virus infection. in this study, 5 nm minocycline did not improve the viability of embryonic mouse cortical and hippocampal neurons infected in vitro with the attenuated sad-d29 strai ...200717409147
location and role of free cysteinyl residues in the sindbis virus e1 and e2 glycoproteins.sindbis virus is a single-stranded positive-sense rna virus. it is composed of 240 copies of three structural proteins: e1, e2, and capsid. these proteins form a mature virus particle composed of two nested t=4 icosahedral shells. a complex network of disulfide bonds in the e1 and e2 glycoproteins is developed through a series of structural intermediates as virus maturation occurs (m. mulvey and d. t. brown, j. virol. 68:805-812, 1994; m. carleton et al., j. virol. 71:1558-1566, 1997). to better ...200717409163
genetic determinants of sindbis virus strain tr339 affecting midgut infection in the mosquito aedes aegypti.mosquito midgut epithelial cells (mec) play a major role in determining whether an arbovirus can successfully infect and be transmitted by mosquitoes. the sindbis virus (sinv) strain tr339 efficiently infects aedes aegypti mec but the sinv strain te/5'2j poorly infects mec. sinv determinants for mec infection have been localized to the e2 glycoprotein. the e2 amino acid sequences of tr339 and te/5'2j differ at two sites, e2-55 and e2-70. we have altered the te/5'2j virus genome by site-directed ...200717412985
a conserved region between the heptad repeats of paramyxovirus fusion proteins is critical for proper f protein folding.paramyxoviruses are a diverse family that utilizes a fusion (f) protein to enter cells via fusion of the viral lipid bilayer with a target cell membrane. although certain regions of the f protein are known to play critical roles in membrane fusion, the function of much of the protein remains unclear. sequence alignment of a set of paramyxovirus f proteins and analysis utilizing block maker identified a region of conserved amino acid sequence in a large domain between the heptad repeats of f1, de ...200717417875
synthesis of some novel heterocyclic compounds derived from diflunisal hydrazide as potential anti-infective and anti-inflammatory agents.three novel series of 2',4'-difluoro-4-hydroxybiphenyl-3-carboxylic acid derivatives namely 4-substituted-1,2,4-triazoline-3-thiones (4a-g); 2-substituted-1,3,4-thiadiazoles (5a-g) and 2-substituted-1,3,4-oxadiazoles (6a-g) have been synthesized. twenty-one of the newly synthesized compounds were tested against various bacteria, fungi, yeast species and virus. in addition, we have replaced the carboxylic acid group of diflunisal with heterocycles and the anti-inflammatory activity of heterocycle ...200717418454
transcriptional activation of interferon-stimulated genes but not of cytokine genes after primary infection of rhesus macaques with dengue virus type 1.macaques are the only animal model used to test dengue virus (denv) vaccine candidates. nevertheless, the pathogenesis of denv in macaques is not well understood. in this work, by using affymetrix oligonucleotide microarrays, we studied the broad transcriptional modifications and cytokine expression profile after infecting rhesus macaques with denv serotype 1. five days after infection, these animals produced a potent, innate antiviral immune response by inducing the transcription of signature g ...200717428947
antiviral activity of oxidized polyamines.polyamines, oxidized by serum amine oxidase, yield aminoaldehydes and hydrogen peroxide. acrolein may be formed from the aminoaldehydes by a spontaneous beta-elimination process. these oxidation products "oxidized polyamines" inhibit bacterial growth and exhibit anticancer activity. the antimicrobial activity of oxidized polyamines is not limited to bacteria; and the inactivation of bacterial viruses, plant viruses and animal viruses, was also reported. bacteriophages of the t-odd series are per ...200717429570
biochemical and genetic analysis of rna cap guanine-n2 methyltransferases from giardia lamblia and schizosaccharomyces pombe.rna cap guanine-n2 methyltransferases such as schizosaccharomyces pombe tgs1 and giardia lamblia tgs2 catalyze methylation of the exocyclic n2 amine of 7-methylguanosine. here we performed a mutational analysis of giardia tgs2, entailing an alanine scan of 17 residues within the minimal active domain. alanine substitutions at phe18, thr40, asp76, asn103 and asp140 reduced methyltransferase specific activity to <3% of wild-type tgs2, thereby defining these residues as essential. alanines at pro14 ...200717284461
synthesis of dioxane-based antiviral agents and evaluation of their biological activities as inhibitors of sindbis virus replication.the crystal structure of the sindbis virus capsid protein contains one or two solvent-derived dioxane molecules in the hydrophobic binding pocket. a bis-dioxane antiviral agent was designed by linking the two dioxane molecules with a three-carbon chain having r,r connecting stereochemistry, and a stereospecific synthesis was performed. this resulted in an effective antiviral agent that inhibited sindbis virus replication with an ec(50) of 14 microm. the synthesis proceeded through an intermediat ...200717287124
distinct sites on the sindbis virus rna-dependent rna polymerase for binding to the promoters for the synthesis of genomic and subgenomic rna.sindbis virus-infected cells make two positive-strand rnas, a genomic (g) rna and a subgenomic (sg) rna. here we report the amino acid sequence in nonstructural protein 4 (nsp4), the viral rna-dependent rna polymerase, that binds to the promoter for the synthesis of g rna. in addition, using a cell-free system that makes both g and sg rna, we show that specific amino acid changes in nsp4 that abolish the synthesis of sg rna have no effect on the synthesis of g rna. our findings indicate that nsp ...200717287268
superinfection exclusion in cells infected with hepatitis c virus.superinfection exclusion is the ability of an established virus infection to interfere with infection by a second virus. in this study, we found that huh-7.5 cells acutely infected with hepatitis c virus (hcv) genotype 2a (chimeric strain j6/jfh) and cells harboring hcv genotype 1a, 1b, or 2a full-length or subgenomic replicons were resistant to infection with cell culture-produced hcv (hcvcc). replicon-containing cells became permissive for hcvcc infection after treatment with an hcv-specific p ...200717287280
infection of cells by sindbis virus at low temperature.sindbis virus, which belongs to the family togaviridae genus alphavirus infects a variety of vertebrate and invertebrate cells. the initial steps of sindbis virus infection involve attachment, penetration and uncoating. two different pathways of infection have been proposed for alphaviruses. one proposed mechanism involves receptor mediated virion endocytosis followed by membrane fusion triggered by endosome acidification. this virus-host membrane fusion model, well established by influenza viru ...200717289103
isg15 modification of the eif4e cognate 4ehp enhances cap structure-binding activity of 4ehp.the expression of the ubiquitin-like molecule isg15 and protein modification by isg15 (isgylation) are strongly activated by interferon, genotoxic stress, and pathogen infection, suggesting that isg15 plays an important role in innate immune responses. 4ehp is an mrna 5' cap structure-binding protein and acts as a translation suppressor by competing with eif4e for binding to the cap structure. here, we report that 4ehp is modified by isg15 and isgylated 4ehp has a much higher cap structure-bindi ...200717289916
progranulin in frontotemporal lobar degeneration and neuroinflammation.progranulin (pgrn) is a pleiotropic protein that has gained the attention of the neuroscience community with recent discoveries of mutations in the gene for pgrn that cause frontotemporal lobar degeneration (ftld). pathogenic mutations in pgrn result in null alleles, and the disease is likely the result of haploinsufficiency. little is known about the normal function of pgrn in the central nervous system apart from a role in brain development. it is expressed by microglia and neurons. in the per ...200717291356
intranasal immunization with synthetic peptides corresponding to the e6 and e7 oncoproteins of human papillomavirus type 16 induces systemic and mucosal cellular immune responses and tumor protection.the e6 and e7 oncoproteins of the high-risk hpv type16 represent ideal targets for hpv vaccine development, they being consistently expressed in cervical cancer lesions. since hpv-16 is primarily transmitted through genital mucosal route, mucosal immune responses constitute an essential feature for vaccination strategies against hpv-associated lesions. we present here evidence showing that mucosal immunization of mice by the intranasal route with a mixture of peptides e7(44-62) and e6(43-57) fro ...200717291642
adaptation of venezuelan equine encephalitis virus lacking 51-nt conserved sequence element to replication in mammalian and mosquito cells.replication of alphaviruses strongly depends on the promoters located in the plus- and minus-strands of virus-specific rnas. the most sophisticated promoter is encoded by the 5' end of the viral genome. this rna sequence is involved in the initiation of translation of viral nsps, and synthesis of both minus- and plus-strands of the viral genome. part of the promoter, the 51-nt conserved sequence element (cse), is located in the nsp1-coding sequence, and this limits the spectrum of possible mutat ...200717292936
stability of a receptor-binding active human immunodeficiency virus type 1 recombinant gp140 trimer conferred by intermonomer disulfide bonding of the v3 loop: differential effects of protein disulfide isomerase on cd4 and coreceptor binding.stable trimeric forms of human immunodeficiency virus recombinant gp140 (rgp140) are important templates for determining the structure of the glycoprotein to assist in our understanding of hiv infection and host immune response. such information will aid the design of therapeutic drugs and vaccines. here, we report the production of a highly stable and trimeric rgp140 derived from a hiv type 1 (hiv-1) subtype d isolate that may be suitable for structural studies. the rgp140 is functional in term ...200717301129
analysis of hepatitis c virus superinfection exclusion by using novel fluorochrome gene-tagged viral genomes.studies of the complete hepatitis c virus (hcv) life cycle have become possible with the development of an infectious cell culture system using the genotype 2a isolate jfh-1. taking advantage of this system in the present study, we investigated whether hcv infection leads to superinfection exclusion, a state in which hcv-infected cells are resistant to secondary hcv infection. to discriminate between viral genomes, we inserted genes encoding fluorescent proteins in frame into the 3'-terminal ns5 ...200717301154
functional characterization of the sindbis virus e2 glycoprotein by transposon linker-insertion mutagenesis.the glycoprotein envelope of alphaviruses consists of two proteins, e1 and e2. e1 is responsible for fusion and e2 is responsible for receptor binding. an atomic structure is available for e1, but one for e2 has not been reported. in this study, transposon linker-insertion mutagenesis was used to probe the function of different domains of e2. a library of mutants, containing 19 amino acid insertions in the e2 glycoprotein sequence of the prototype alphavirus, sindbis virus (sinv), was generated. ...200717306321
complement contributes to inflammatory tissue destruction in a mouse model of ross river virus-induced disease.arthritogenic alphaviruses, including ross river virus (rrv) and chikungunya virus, are mosquito-borne viruses that cause significant human disease worldwide, including explosive epidemics that can result in thousands to millions of infected individuals. similar to infection of humans, infection of c57bl/6 mice with rrv results in severe monocytic inflammation of bone, joint, and skeletal muscle tissues. we demonstrate here that the complement system, an important component of the innate immune ...200717314163
expression of particulate-form of japanese encephalitis virus envelope protein in a stably transfected drosophila cell line.japanese encephalitis virus (jev), a member of the family flaviviridae, is an important mosquito-borne human pathogen. its envelope glycoprotein (e) is the major determinant of the pathogenicity and host immune responses. in the present study, we explored the feasibility of producing recombinant jev e protein in the virus-free drosophila expression system.200717324254
methamphetamine-induced structural plasticity in the dorsal striatum.repeated exposure to psychostimulant drugs produces long-lasting changes in dendritic structure, presumably reflecting a reorganization in patterns of synaptic connectivity, in brain regions that mediate the psychomotor activating and incentive motivational effects of these drugs, including the nucleus accumbens and prefrontal cortex. however, repeated exposure to psychostimulant drugs also facilitates a transition in the control of some behaviors from action-outcome associations to behavior con ...200717328779
development of sindbis viruses encoding nsp2/gfp chimeric proteins and their application for studying nsp2 functioning.sindbis virus (sinv) is one of almost 30 currently known alphaviruses. in infected cells, it produces only a few proteins that function in virus replication and interfere with the development of the antiviral response. one of the viral nonstructural proteins, nsp2, not only exhibits protease and rna helicase activities that are directly involved in viral rna replication but also plays critical roles in the development of transcriptional and translational shutoffs in the sinv-infected cells. thes ...200717329335
thiol/disulfide exchange is required for membrane fusion directed by the newcastle disease virus fusion protein.newcastle disease virus (ndv), an avian paramyxovirus, initiates infection with attachment of the viral hemagglutinin-neuraminidase (hn) protein to sialic acid-containing receptors, followed by fusion of viral and cell membranes, which is mediated by the fusion (f) protein. like all class 1 viral fusion proteins, the paramyxovirus f protein is thought to undergo dramatic conformational changes upon activation. how the f protein accomplishes extensive conformational rearrangements is unclear. sin ...200717151113
alphavirus replicon approach to promoterless analysis of ires elements.here we describe a system for promoterless analysis of putative internal ribosome entry site (ires) elements using an alphavirus (family togaviridae) replicon vector. the system uses the alphavirus subgenomic promoter to produce transcripts that, when modified to contain a spacer region upstream of an ires element, allow analysis of cap-independent translation of genes of interest (goi). if the ires element is removed, translation of the subgenomic transcript can be reduced >95% compared to the ...200717156813
herpes simplex virus type 2-mediated disease is reduced in mice lacking rnase l.rnase l helps mediate the antiviral state induced by type i interferons (ifnalphabeta). although herpes simplex virus (hsv) encodes inhibitors of the ifnalphabeta-induced antiviral response, the ifnalphabeta system serves the body as a first line of defense against hsv. we investigated whether rnase l limits hsv-2 replication and virulence. rnasel(-/-) and wild-type c57bl/6 mice were infected intravaginally with hsv-2 strain 333. although initial replication in the genital epithelium was similar ...200717157346
metabotropic glutamate receptor 4-immunopositive terminals of medium-sized spiny neurons selectively form synapses with cholinergic interneurons in the rat neostriatum.metabotropic glutamate receptor 4 (mglur4) is localized mainly to presynaptic membranes in the brain. rat neostriatum has been reported to contain two types of mglur4-immunoreactive axon varicosities: small, weakly immunoreactive varicosities that were distributed randomly (type 1) and large, intensely immunoreactive ones that were often aligned linearly (type 2). in the present study, most type 1 terminals formed asymmetric synapses on dendritic spines, whereas type 2 terminals made symmetric s ...200717177262
a mouse cell-adapted ns4b mutation attenuates west nile virus rna synthesis.an adaptive mutation (e249g) within west nile virus (wnv) ns4b gene was consistently recovered from replicon rnas in c3h/he mouse cells. the e249g is located at the c-terminal tail of ns4b predicted to be on the cytoplasmic side of the endoplasmic reticulum membrane. the e249g substitution reduced replicon rna synthesis. compared with the wild-type ns4b, the e249g mutant protein exhibited a similar efficiency in evasion of interferon-beta response. recombinant e249g virus exhibited smaller plaqu ...200717178141
inhibition of filovirus replication by the zinc finger antiviral protein.the zinc finger antiviral protein (zap) was recently shown to inhibit moloney murine leukemia virus and sindbis virus replication. we tested whether zap also acts against ebola virus (ebov) and marburg virus (marv). antiviral effects were observed after infection of cells expressing the n-terminal part of zap fused to the product of the zeocin resistance gene (nzap-zeo) as well as after infection of cells inducibly expressing full-length zap. ebov was inhibited by up to 4 log units, whereas marv ...200717182693
long-distance rna-rna interactions between terminal elements and the same subset of internal elements on the potato virus x genome mediate minus- and plus-strand rna synthesis.potexvirus genomes contain conserved terminal elements that are complementary to multiple internal octanucleotide elements. both local sequences and structures at the 5' terminus and long-distance interactions between this region and internal elements are important for accumulation of potato virus x (pvx) plus-strand rna in vivo. in this study, the role of the conserved hexanucleotide motif within sl3 of the 3' ntr and internal conserved octanucleotide elements in minus-strand rna synthesis was ...200717185361
the zinc-finger antiviral protein recruits the rna processing exosome to degrade the target mrna.zinc-finger antiviral protein (zap) is a host antiviral factor that specifically inhibits the replication of moloney murine leukemia virus (mlv) and sindbis virus (sin) by preventing accumulation of the viral mrna in the cytoplasm. in previous studies, we demonstrated that zap directly binds to its specific target mrnas. in this article, we provide evidence indicating that zap recruits the rna processing exosome to degrade the target rna. zap comigrated with the exosome in sucrose or glycerol ve ...200717185417
caspase 3-dependent cell death of neurons contributes to the pathogenesis of west nile virus encephalitis.west nile virus (wnv) is a neurotropic, arthropod-borne flavivirus that has become a significant global cause of viral encephalitis. to examine the mechanisms of wnv-induced neuronal death and the importance of apoptosis in pathogenesis, we evaluated the role of a key apoptotic regulator, caspase 3. wnv infection induced caspase 3 activation and apoptosis in the brains of wild-type mice. notably, congenic caspase 3(-/-) mice were more resistant to lethal wnv infection, although there were no sig ...200717192305
the taming of the cell penetrating domain of the hiv tat: myths and realities.protein transduction with cell penetrating peptides over the past several years has been shown to be an effective way of delivering proteins in vitro and now several reports have also shown valuable in vivo applications in correcting disease states. an impressive bioinspired phenomenon of crossing biological barriers came from hiv transactivator tat protein. specifically, the protein transduction domain of hiv tat has been shown to be a potent pleiotropic peptide in protein delivery. various app ...200717196289
enzymatic defects of the nsp2 proteins of semliki forest virus temperature-sensitive mutants.we have analyzed the biochemical consequences of mutations that affect viral rna synthesis in semliki forest virus temperature-sensitive (ts) mutants. of the six mutations mapping in the multifunctional replicase protein nsp2, three were located in the n-terminal helicase region and three were in the c-terminal protease domain. wild-type and mutant nsp2s were expressed, purified, and assayed for nucleotide triphosphatase (ntpase), rna triphosphatase (rtpase), and protease activities in vitro at ...200717202213
heparan sulfate binding can contribute to the neurovirulence of neuroadapted and nonneuroadapted sindbis viruses.cell culture-adapted laboratory strains of sindbis virus (sb) exhibit efficient initial attachment to cell surface heparan sulfate (hs) receptors. in contrast, non-cell-adapted strains, such as the sb consensus sequence virus tr339, interact weakly with hs and cell surfaces. regardless of their hs binding phenotype, most sb strains do not cause fatal disease in adult mice, whether inoculated subcutaneously (s.c.) or intracranially (i.c.). however, laboratory strains of sb can be rendered neurovi ...200717215278
a mouse-adapted sars-coronavirus causes disease and mortality in balb/c mice.no single animal model for severe acute respiratory syndrome (sars) reproduces all aspects of the human disease. young inbred mice support sars-coronavirus (sars-cov) replication in the respiratory tract and are available in sufficient numbers for statistical evaluation. they are relatively inexpensive and easily accessible, but their use in sars research is limited because they do not develop illness following infection. older (12- to 14-mo-old) balb/c mice develop clinical illness and pneumoni ...200717222058
negative regulation of isg15 e3 ligase efp through its autoisgylation.the function of ubiquitin-like protein isg15 and protein modification by isg15 (isgylation) has been an enigma for many years. recently, the research of isgylation has been accelerated by the identification of the enzymes involved in the isg15 conjugation process. our previous study identified the interferon inducible protein efp as an isg15 isopeptide ligase (e3) for 14-3-3sigma. in this study, we show that isg15 e3 ligase efp can be modified by isg15. two ubiquitin e2 conjugating enzymes, ubch ...200717222803
correlation between breakdown of the blood-brain barrier and disease outcome of viral encephalitis in mice.changes in the permeability of the blood-brain barrier (bbb) were evaluated in two mouse models of viral encephalitis. the ability of sodium fluorescein (nafl) to cross the bbb from the serum into the central nervous system was assayed in animals inoculated with virulent strains of either banzi or semliki forest viruses. to test the hypothesis that increases in bbb permeability were associated with poor disease outcome subsequent experiments measured bbb permeability in conjunction with treatmen ...200717223204
ifn-stimulated gene 15 functions as a critical antiviral molecule against influenza, herpes, and sindbis viruses.type i interferons (ifns) play an essential role in the host response to viral infection through the induction of numerous ifn-stimulated genes (isgs), including important antiviral molecules such as pkr, rnase l, mx, and inos. yet, additional antiviral isgs likely exist. ifn-stimulated gene 15 (isg15) is a ubiquitin homolog that is rapidly up-regulated after viral infection, and it conjugates to a wide array of host proteins. although it has been hypothesized that isg15 functions as an antivira ...200717227866
early restriction of alphavirus replication and dissemination contributes to age-dependent attenuation of systemic hyperinflammatory disease.severity of alphavirus infection in humans tends to be strongly age-dependent and several studies using laboratory-adapted sindbis virus (sb) ar339 strains have indicated that sb-induced disease in mice is similarly contingent upon host developmental status. in the current studies, the consensus wild-type sb, tr339, and in vivo imaging technology have been utilized to examine virus replication and disease manifestations in mice infected subcutaneously at 5 days of age (5d) vs 11d. initial virule ...200717251570
dengue virus type 2: replication and tropisms in orally infected aedes aegypti mosquitoes.to be transmitted by its mosquito vector, dengue virus (denv) must infect midgut epithelial cells, replicate and disseminate into the hemocoel, and finally infect the salivary glands, which is essential for transmission. the extrinsic incubation period (eip) is very relevant epidemiologically and is the time required from the ingestion of virus until it can be transmitted to the next vertebrate host. the eip is conditioned by the kinetics and tropisms of virus replication in its vector. here we ...200717263893
capsid protein of eastern equine encephalitis virus inhibits host cell gene expression.eastern equine encephalitis virus (eeev) causes sporadic but often severe cases of human and equine neurological disease in north america. to determine how eeev may evade innate immune responses, we screened individual eeev proteins for the ability to rescue the growth of a newcastle disease virus expressing green fluorescent protein (ndv-gfp) from the antiviral effects of interferon (ifn). only expression of the eeev capsid facilitated ndv-gfp replication. inhibition of the antiviral effects of ...200717267491
synthesis and antiviral activities of new acyclic and "double-headed" nucleoside analogues.to develop an understanding of the structure-activity relationships for the inhibition of orthopoxviruses by nucleoside analogues, a variety of novel chemical entities were synthesized. these included a series of pyrimidine 5-hypermodified acyclic nucleoside analogues based upon recently discovered new leads, and some previously unknown "double-headed" or "abbreviated" nucleosides. none of the synthetic products possessed significant activity against two representative orthopoxviruses; namely, v ...200717270235
methylation: a regulator of hiv-1 replication?recent characterizations of methyl transferases as regulators of cellular processes have spurred investigations into how methylation events might influence the hiv-1 life cycle. emerging evidence suggests that protein-methylation can positively and negatively regulate hiv-1 replication. how dna- and rna- methylation might impact hiv-1 is also discussed.200717274823
role of the amphipathic peptide of semliki forest virus replicase protein nsp1 in membrane association and virus replication.semliki forest virus rna replication takes place in association with specific cytoplasmic vacuoles, derived from the endosomal apparatus. of the four virus-encoded replicase proteins, nsp1 serves as the membrane anchor of the replication complex. an amphipathic peptide segment, g245stlytesrkllrswhlpsv264, has been implicated in the membrane binding of nsp1. nsp1 variants with changes within the peptide were studied after protein expression and in the context of virus infection. proteins with mut ...200717093195
chlorella viruses contain genes encoding a complete polyamine biosynthetic pathway.two genes encoding the putative polyamine biosynthetic enzymes agmatine iminohydrolase (aih) and n-carbamoylputrescine amidohydrolase (cpa) were cloned from the chloroviruses pbcv-1, ny-2a and mt325. they were expressed in escherichia coli to form c-terminal (his)6-tagged proteins and the recombinant proteins were purified by ni2+-binding affinity chromatography. the biochemical properties of the two enzymes are similar to aih and cpa enzymes from arabidopsis thaliana and pseudomonas aeruginosa. ...200717101165
the old world and new world alphaviruses use different virus-specific proteins for induction of transcriptional shutoff.alphaviruses are widely distributed throughout the world. during the last few thousand years, the new world viruses, including venezuelan equine encephalitis virus (veev) and eastern equine encephalitis virus (eeev), evolved separately from those of the old world, i.e., sindbis virus (sinv) and semliki forest virus (sfv). nevertheless, the results of our study indicate that both groups have developed the same characteristic: their replication efficiently interferes with cellular transcription an ...200717108023
selective repression of translation by the brome mosaic virus 1a rna replication protein.differential expression of viral replication proteins is essential for successful infection. we report here that overexpression of the brome mosaic virus (bmv) 1a protein can repress viral rna replication in a dosage-dependent manner. using rna replication-incompetent reporter constructs, repression of translation from bmv rna1 and rna2 was observed, suggesting that the effect on translation of the bmv rna replication proteins is responsible for the decrease in rna levels. furthermore, repressio ...200717108036
variable deficiencies in the interferon response enhance susceptibility to vesicular stomatitis virus oncolytic actions in glioblastoma cells but not in normal human glial cells.with little improvement in the poor prognosis for humans with high-grade glioma brain tumors, alternative therapeutic strategies are needed. as such, selective replication-competent oncolytic viruses may be useful as a potential treatment modality. here we test the hypothesis that defects in the interferon (ifn) pathway could be exploited to enhance the selective oncolytic profile of vesicular stomatitis virus (vsv) in glioblastoma cells. two green fluorescent protein-expressing vsv strains, rec ...200717108037
tumor necrosis factor (tnf) protects resistant c57bl/6 mice against herpes simplex virus-induced encephalitis independently of signaling via tnf receptor 1 or 2.tumor necrosis factor (tnf) is a multifunctional cytokine that has a role in induction and regulation of host innate and adaptive immune responses. the importance of tnf antiviral mechanisms is reflected by the diverse strategies adopted by different viruses, particularly members of the herpesvirus family, to block tnf responses. tnf binds and signals through two receptors, tnfrsf1a (tnf receptor 1 [tnfr1], or p55) and tnfrsf1b (tnfr2, or p75). we report here that herpes simplex virus 1 (hsv-1) ...200717108044
infection of ixodes scapularis ticks with rickettsia monacensis expressing green fluorescent protein: a model system.ticks (acari: ixodidae) are ubiquitous hosts of rickettsiae (rickettsiaceae: rickettsia), obligate intracellular bacteria that occur as a continuum from nonpathogenic arthropod endosymbionts to virulent pathogens of both arthropod vectors and vertebrates. visualization of rickettsiae in hosts has traditionally been limited to techniques utilizing fixed tissues. we report epifluorescence microscopy observations of unfixed tick tissues infected with a spotted fever group endosymbiont, rickettsia m ...200717125789
mutagenesis of the la crosse virus glycoprotein supports a role for gc (1066-1087) as the fusion peptide.the la crosse virus (lacv) m segment encodes two glycoproteins (gn and gc), and plays a critical role in the neuropathogenesis of lacv infection as the primary determinant of neuroinvasion. a recent study from our group demonstrated that the region comprising the membrane proximal two-thirds of gc, amino acids 860-1442, is critical in mediating lacv fusion and entry. furthermore, computational analysis identified structural similarities between a portion of this region, amino acids 970-1350, and ...200717027056
identification of linear heparin-binding peptides derived from human respiratory syncytial virus fusion glycoprotein that inhibit infectivity.it has been shown previously that the fusion glycoprotein of human respiratory syncytial virus (rsv-f) interacts with cellular heparan sulfate. synthetic overlapping peptides derived from the f-protein sequence of rsv subtype a (strain a2) were tested for their ability to bind heparin using heparin-agarose affinity chromatography (haac). this evaluation identified 15 peptides representing eight linear heparin-binding domains (hbds) located within f1 and f2 and spanning the protease cleavage acti ...200717050595
a chimeric alphavirus rna replicon gene-based vaccine for human parainfluenza virus type 3 induces protective immunity against intranasal virus challenge.parainfluenza virus type 3 (piv3) infections continue to be a significant health risk for infants, young children, and immunocompromised adults. we describe a gene-based vaccine strategy against piv3 using replication-defective alphavirus vectors. these rna replicon vectors, delivered as virus-like particles and expressing the piv3 hemagglutinin-neuraminidase glycoprotein, were shown to be highly immunogenic in mice and hamsters, inducing piv3-specific neutralizing antibody responses. importantl ...200717052811
heterogeneous nuclear ribonuclear protein k interacts with sindbis virus nonstructural proteins and viral subgenomic mrna.alphaviruses are a group of arthropod-borne human and animal pathogens that can cause epidemics of significant public health and economic consequence. alphavirus rna synthesis requires four virally encoded nonstructural proteins and probably a number of cellular proteins. using comparative two-dimensional electrophoresis we were able to identify proteins enriched in cytoplasmic membrane fractions containing viral rna synthetic complexes following infection with sindbis virus. our studies demonst ...200717561226
human muscle satellite cells as targets of chikungunya virus infection.chikungunya (chik) virus is a mosquito-transmitted alphavirus that causes in humans an acute infection characterised by fever, polyarthralgia, head-ache, and myalgia. since 2005, the emergence of chik virus was associated with an unprecedented magnitude outbreak of chik disease in the indian ocean. clinically, this outbreak was characterized by invalidating poly-arthralgia, with myalgia being reported in 97.7% of cases. since the cellular targets of chik virus in humans are unknown, we studied t ...200717565380
the early protective thymus-independent antibody response to foot-and-mouth disease virus is mediated by splenic cd9+ b lymphocytes.infection of mice with cytopathic foot-and-mouth disease virus (fmdv) induces a rapid and specific thymus-independent (ti) neutralizing antibody response that promptly clears the virus. herein, it is shown that fmdv-infected dendritic cells (dcs) directly stimulate splenic innate-like cd9(+) b lymphocytes to rapidly (3 days) produce neutralizing anti-fmdv immunoglobulin m antibodies without t-lymphocyte collaboration. in contrast, neither follicular (cd9(-)) b lymphocytes from the spleen nor b l ...200717567692
coincident regulation of pkcdelta in human platelets by phosphorylation of tyr311 and tyr565 and phospholipase c signalling.pkc (protein kinase c)d plays a complex role in platelets, having effects on both positive and negative signalling functions. it is phosphorylated on tyrosine residues in response to thrombin and collagen, and it has recently been shown that tyr311 is phosphorylated in response to par (protease-activated receptor) 1 and par4 receptor activation. in the present study, we show that tyr311 and tyr565 are phosphorylated in response to thrombin, and have examined the interplay between phosphorylation ...200717570831
viruses as anticancer drugs.oncolytic viruses are being developed as anticancer drugs. they propagate selectively in tumor tissue and destroy it without causing excessive damage to normal non-cancerous tissues. when used as drugs, they must meet stringent criteria for safety and efficacy and be amenable to pharmacological study in human subjects. specificity for neoplastic tissue is the key to safety, and this goal can be achieved through a variety of ingenious virus-engineering strategies. antiviral immunity remains a sig ...200717573126
regulation of dendritic excitability by activity-dependent trafficking of the a-type k+ channel subunit kv4.2 in hippocampal neurons.voltage-gated a-type k+ channel kv4.2 subunits are highly expressed in the dendrites of hippocampal ca1 neurons. however, little is known about the subcellular distribution and trafficking of kv4.2-containing channels. here we provide evidence for activity-dependent trafficking of kv4.2 in hippocampal spines and dendrites. live imaging and electrophysiological recordings showed that kv4.2 internalization is induced rapidly upon glutamate receptor stimulation. kv4.2 internalization was clathrin m ...200717582333
posttranslational n-glycosylation of the hepatitis b virus large envelope protein.the addition of n-linked glycans to proteins is normally a cotranslational process that occurs during translocation of the nascent protein to the endoplasmic reticulum. here, we report on an exception to this rule occurring on the hepatitis b virus (hbv) large l envelope protein that is a subject to co-plus posttranslational n-glycosylation.200717537250
de novo initiation of rna synthesis by the arterivirus rna-dependent rna polymerase.all plus-strand rna viruses encode an rna-dependent rna polymerase (rdrp) that functions as the catalytic subunit of the viral replication/transcription complex, directing viral rna synthesis in concert with other viral proteins and, sometimes, host proteins. rna synthesis essentially can be initiated by two different mechanisms, de novo initiation and primer-dependent initiation. most viral rdrps have been identified solely on the basis of comparative sequence analysis, and for many viruses the ...200717537850
next generation: tuberculosis vaccines that elicit protective cd8+ t cells.tuberculosis continues to cause considerable human morbidity and mortality worldwide, particularly in people coinfected with hiv. the emergence of multidrug resistance makes the medical treatment of tuberculosis even more difficult. thus, the development of a tuberculosis vaccine is a global health priority. here we review the data concerning the role of cd8+ t cells in immunity to tuberculosis and consider how cd8+ t cells can be elicited by vaccination. many immunization strategies have the po ...200717542758
novel toxicity of the unedited glur2 ampa receptor subunit dependent on surface trafficking and increased ca2+-permeability.rna editing modifies the glur2 ampa receptor subunit pore loop at the q/r site and limits receptor ca(2+) permeability. editing failure is implicated in neurodegenerative diseases, including amyotrophic lateral sclerosis. we show that channels with unedited glur2 are highly toxic in cultured hippocampal neurons. toxicity exceeds that of other ca(2+)-permeable ampa receptor types and is influenced by agonist binding site mutations, ability to desensitize, and extracellular ca(2+) levels. signific ...200717544687
neuroprotective interventions targeting detrimental host immune responses protect mice from fatal alphavirus encephalitis.systemic treatment with the tetracycline derivative, minocycline, attenuates neurologic deficits in animal models of amyotrophic lateral sclerosis, hypoxic-ischemic brain injury, and multiple sclerosis. inhibition of microglial activation within the cns is 1 mechanism proposed to underlie the beneficial effects of the drug in these systems. given the widening scope of acute viral encephalitis caused by mosquito-borne pathogens, we investigated the therapeutic effects of minocycline in a murine m ...200717549013
environment determines fidelity for an rna virus replicase.the rate of insertion and deletion mutations of the replicase of cucumber mosaic virus (cmv) was determined in planta by using a parasitic satellite rna (satrna) as a reporter. we found that the cmv replicase had different fidelity in different environments, with important implications in viral disease evolution. insertions were very rare events, irrespective of the region of the satrna genome assayed and independent of the hosts tested. on the other hand, deletion events were more frequent but ...200717553888
semliki forest virus nonstructural protein 2 is involved in suppression of the type i interferon response.the type i interferons (ifns) are potent mediators of antiviral immunity, and many viruses have developed means to block their expression or their effects. semliki forest virus (sfv) infection induces rapid and profound silencing of host cell gene expression, a process believed to be important for the inhibition of the ifn response. in sfv-infected cells, a large proportion of the nonstructural protein nsp2 is found in the nucleus, but a role for this localization has not been described. in this ...200717553895
mutations at the palmitoylation site of non-structural protein nsp1 of semliki forest virus attenuate virus replication and cause accumulation of compensatory mutations.the replicase of semliki forest virus (sfv) consists of four non-structural proteins, designated nsp1-4, and is bound to cellular membranes via an amphipathic peptide and palmitoylated cysteine residues of nsp1. it was found that mutations preventing nsp1 palmitoylation also attenuated virus replication. the replacement of these cysteines by alanines, or their deletion, abolished virus viability, possibly due to disruption of interactions between nsp1 and nsp4, which is the catalytic subunit of ...200717554031
synaptic scaffolding molecule alpha is a scaffold to mediate n-methyl-d-aspartate receptor-dependent rhoa activation in dendrites.synaptic scaffolding molecule (s-scam) interacts with a wide variety of molecules at excitatory and inhibitory synapses. it comprises three alternative splicing variants, s-scamalpha, -beta, and -gamma. we generated mutant mice lacking specifically s-scamalpha. s-scamalpha-deficient mice breathe and feed normally but die within 24 h after birth. primary cultured hippocampal neurons from mutant mice have abnormally elongated dendritic spines. exogenously expressed s-scamalpha corrects this abnorm ...200717438139
viral translation is coupled to transcription in sindbis virus-infected cells.during the late phase of sindbis virus infection, the viral subgenomic mrna is translated efficiently in bhk cells, whereas host protein synthesis is inhibited. however, transfection of in vitro-generated sindbis virus subgenomic mrna leads to efficient translation in uninfected bhk cells, whereas it is a poor substrate in infected cells. therefore, the structure of the subgenomic mrna itself is not sufficient to confer its translatability in infected cells. in this regard, translation of the su ...200717442713
cellular and humoral immune responses to alphavirus replicon vaccines expressing cytomegalovirus pp65, ie1, and gb proteins.development of vaccines against cytomegalovirus (cmv) is an important public health priority. we used a propagation-defective, single-cycle rna replicon vector system derived from an attenuated strain of an alphavirus, venezuelan equine encephalitis virus, to produce virus-like replicon particles (vrp) expressing various combinations of pp65, ie1, or gb proteins of human cmv. protein expression in vrp-infected cells was highest with single-promoter replicons expressing pp65, ie1, a pp65/ie1 fusi ...200717442845
emerging zoonoses and vector-borne infections affecting humans in europe.the purpose of this study was to assess and describe the current spectrum of emerging zoonoses between 2000 and 2006 in european countries. a computerized search of the medline database from january 1966 to august 2006 for all zoonotic agents in european countries was performed using specific criteria for emergence. fifteen pathogens were identified as emerging in europe from 2000 to august 2006: rickettsiae spp., anaplasma phagocytophilum, borrelia burgdorferi, bartonella spp., francisella tula ...200717445320
[ockelbo disease: stinging fly transmitted polyarthritis in scandinavia]. 200717447272
rapid membrane fusion of individual virus particles with supported lipid bilayers.many enveloped viruses employ low-ph-triggered membrane fusion during cell penetration. solution-based in vitro assays in which viruses fuse with liposomes have provided much of our current biochemical understanding of low-ph-triggered viral membrane fusion. here, we extend this in vitro approach by introducing a fluorescence assay using single particle tracking to observe lipid mixing between individual virus particles (influenza or sindbis) and supported lipid bilayers. our single-particle exp ...200717449662
the opioid receptor antagonist, naloxone, protects spinal motor neurons in a murine model of alphavirus encephalomyelitis.spread of neuroadapted sindbis virus (nsv) to motor neurons (mn) of the spinal cord (sc) causes severe hind limb weakness in c57bl/6 mice and models the paralysis that can accompany alphavirus and flavivirus encephalomyelitis in humans. the fate of spinal mn dictates the severity of nsv-induced paralysis, and recent data suggest that mn damage can occur indirectly via the actions of activated microglial cells. because the opioid receptor antagonist, naloxone (nal), blocks microglial-mediated neu ...200717459376
viral alteration of cellular translational machinery increases defective ribosomal products.here we show that cells expressing genes inserted into semliki forest virus (sfv) vectors generate a large fraction of defective ribosomal products (drips) due to frequent initiation on downstream met residues. in monopolizing the host cell translational machinery, sfv reduces levels of translation eukaryotic initiation factor 4e (eif4e), diminishes phosphorylation of ribosome subunit s6, and phosphorylates translation initiation factor eif2alpha. we show that the last event is required for sfv ...200717459927
pick1 interacts with alpha7 neuronal nicotinic acetylcholine receptors and controls their clustering.central to synaptic function are protein scaffolds associated with neurotransmitter receptors. alpha7 neuronal nicotinic acetylcholine receptors (nachrs) modulate network activity, neuronal survival and cognitive processes in the cns, but protein scaffolds that interact with these receptors are unknown. here we show that the pdz-domain containing protein pick1 binds to alpha7 nachrs and plays a role in their clustering. pick1 interacted with the alpha7 cytoplasmic loop in yeast in a pdz-dependen ...200717467288
seco-pregnane steroids target the subgenomic rna of alphavirus-like rna viruses.plants have evolved multiple mechanisms to selectively suppress pathogens by production of secondary metabolites with antimicrobial activities. therefore, direct selections for antiviral compounds from plants can be used to identify new agents with potent antiviral activity but not toxic to hosts. here, we provide evidence that a class of compounds, seco-pregnane steroid glaucogenin c and its monosugar-glycoside cynatratoside a of strobilanthes cusia and three new pantasugar-glycosides of glauco ...200717470783
novel strategy for treatment of viral central nervous system infection by using a cell-permeating inhibitor of c-jun n-terminal kinase.viral encephalitis is a major cause of morbidity and mortality worldwide, yet there is no proven efficacious therapy for most viral infections of the central nervous system (cns). many of the viruses that cause encephalitis induce apoptosis and activate c-jun n-terminal kinase (jnk) following infection. we have previously shown that reovirus infection of epithelial cell lines activates jnk-dependent apoptosis. we now show that reovirus infection resulted in activation of jnk and caspase-3 in the ...200717475657
influenza virus hemagglutinin and neuraminidase, but not the matrix protein, are required for assembly and budding of plasmid-derived virus-like particles.for influenza virus, we developed an efficient, noncytotoxic, plasmid-based virus-like particle (vlp) system to reflect authentic virus particles. this system was characterized biochemically by analysis of vlp protein composition, morphologically by electron microscopy, and functionally with a vlp infectivity assay. the vlp system was used to address the identity of the minimal set of viral proteins required for budding. combinations of viral proteins were expressed in cells, and the polypeptide ...200717475660
the alphavirus 6k protein activates endogenous ionic conductances when expressed in xenopus oocytes.the alphavirus sindbis 6k protein is involved in several functions. it contributes to the processing and membrane insertion of e1 and pe2 viral envelope glycoproteins and to virus budding. it also permeabilizes escherichia coli and mammalian cells. these viroporin-like properties have been proposed to help virus budding by modifying membrane permeabilities. we expressed sindbis virus 6k crna in xenopus oocytes to further characterize the effect of 6k on membrane conductances and permeabilization ...200717483865
poliovirus induces bax-dependent cell death mediated by c-jun nh2-terminal kinase.poliovirus (pv) is the causal agent of paralytic poliomyelitis, a disease that involves the destruction of motor neurons associated with pv replication. in pv-infected mice, motor neurons die through an apoptotic process. however, mechanisms by which pv induces cell death in neuronal cells remain unclear. here, we demonstrate that pv infection of neuronal imr5 cells induces cytochrome c release from mitochondria and loss of mitochondrial transmembrane potential, both of which are evidence of mit ...200717494073
enucleated l929 cells support invasion, differentiation, and multiplication of trypanosoma cruzi parasites.cell infection with trypanosoma cruzi, the agent of chagas' disease, begins with the uptake of infective trypomastigotes within phagosomes and their release into the cytosol, where they transform into replicating amastigotes; the latter, in turn, differentiate into cytolytically released and infective trypomastigotes. we ask here if the t. cruzi infection program can develop in enucleated host cells. monolayers of l929 cells, enucleated by centrifugation in the presence of cytochalasin b and kep ...200717502387
interaction of tia-1/tiar with west nile and dengue virus products in infected cells interferes with stress granule formation and processing body assembly.the west nile virus minus-strand 3' terminal stem loop (sl) rna was previously shown to bind specifically to cellular stress granule (sg) components, t cell intracellular antigen-1 (tia-1) and the related protein tiar. in vitro tiar binding was 10 times more efficient than tia-1. the 3'(-)sl functions as the promoter for genomic rna synthesis. colocalization of tiar and tia-1 with the viral replication complex components dsrna and ns3 was observed in the perinuclear regions of west nile virus- a ...200717502609
comparative analysis of the alphavirus-based vectors expressing rift valley fever virus glycoproteins.during the last decade, alphaviruses became widely used for expression of heterologous genetic information and development of recombinant vaccines against a variety of human and animal pathogens. in this study, we compared a number of vectors based on the genome of sindbis (sinv) and venezuelan equine encephalitis (veev) viruses for their ability to express the rift valley fever virus (rvfv) envelope glycoprotein gn and induce a protective immune response against rvfv infection. our results sugg ...200717507072
lipid rafts of primary endothelial cells are essential for kaposi's sarcoma-associated herpesvirus/human herpesvirus 8-induced phosphatidylinositol 3-kinase and rhoa-gtpases critical for microtubule dynamics and nuclear delivery of viral dna but dispensable for binding and entry.early during de novo infection of human microvascular dermal endothelial (hmvec-d) cells, kaposi's sarcoma-associated herpesvirus (kshv) (human herpesvirus 8 [hhv-8]) induces the host cell's preexisting fak, src, phosphatidylinositol 3-kinase (pi3-k), rho-gtpases, diaphanous-2 (dia-2), ezrin, protein kinase c-zeta, extracellular signal-regulated kinase 1/2 (erk1/2), and nf-kappab signal pathways that are critical for virus entry, nuclear delivery of viral dna, and initiation of viral gene expres ...200717507466
restricted tissue tropism and acquired resistance to sindbis viral vector expression in the absence of innate and adaptive immunity.our previous studies suggest that replication-defective sindbis vectors might be promising agents for specific tumor targeting and detection. however, the effects of innate and/or adaptive anti-viral immunity, in particular, the ifn-i/stat1 signaling pathway, may impact their therapeutic potential. using a bioluminescent imaging system, we demonstrate that although most normal cells are not permissively transduced by replication-defective sindbis vector, transduction of liver non-sinusoidal endo ...200717508007
virus inactivation by protein denaturants used in affinity chromatography.virus inactivation by a number of protein denaturants commonly used in gel affinity chromatography for protein elution and gel recycling has been investigated. the enveloped viruses sindbis, herpes simplex-1 and vaccinia, and the non-enveloped virus polio-1 were effectively inactivated by 0.5 m sodium hydroxide, 6 m guanidinium thiocyanate, 8 m urea and 70% ethanol. however, ph 2.6, 3 m sodium thiocyanate, 6 m guanidinium chloride and 20% ethanol, while effectively inactivating the enveloped vir ...200717517521
the neuregulin-1 receptor erbb4 controls glutamatergic synapse maturation and plasticity.neuregulin-1 (nrg1) signaling participates in numerous neurodevelopmental processes. through linkage analysis, nrg1 has been associated with schizophrenia, although its pathophysiological role is not understood. the prevailing models of schizophrenia invoke hypofunction of the glutamatergic synapse and defects in early development of hippocampal-cortical circuitry. here, we show that the erbb4 receptor, as a postsynaptic target of nrg1, plays a key role in activity-dependent maturation and plast ...200717521571
functional requirements of the yellow fever virus capsid protein.although it is known that the flavivirus capsid protein is essential for genome packaging and formation of infectious particles, the minimal requirements of the dimeric capsid protein for virus assembly/disassembly have not been characterized. by use of a trans-packaging system that involved packaging a yellow fever virus (yfv) replicon into pseudo-infectious particles by supplying the yfv structural proteins using a sindbis virus helper construct, the functional elements within the yfv capsid p ...200717526891
comparison of four methods using throat swabs to confirm rubella virus infection.laboratory tests are essential for confirming sporadic cases and outbreaks of rubella. detection of rubella virus is often necessary to confirm rubella cases and to identify specimens to be used to characterize wild-type rubella viruses. the sensitivities of four methods for detecting rubella virus infection using throat swabs, which had been collected in henan and anhui provinces in china, were evaluated. the methods used were reverse transcription (rt)-pcr followed by southern hybridization us ...200717596370
characterization of reemerging chikungunya virus.an unprecedented epidemic of chikungunya virus (chikv) infection recently started in countries of the indian ocean area, causing an acute and painful syndrome with strong fever, asthenia, skin rash, polyarthritis, and lethal cases of encephalitis. the basis for chikungunya disease and the tropism of chikv remain unknown. here, we describe the replication characteristics of recent clinical chikv strains. human epithelial and endothelial cells, primary fibroblasts and, to a lesser extent, monocyte ...200717604450
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