| on the pathogenesis of semliki forest virus (sfv) infection in the hamster. | | 1967 | 6022753 |
| virus nucleic acid and interferon formation. | | 1967 | 6049387 |
| the course of semliki forest virus infection in mice. | | 1967 | 6051241 |
| the effect of interferon on the synthesis of rna in chick cells infected with semliki forest virus. | | 1967 | 6060240 |
| the effect of interferon on the synthesis and activity of an rna polymerase isolated from chick cells infected with semliki forest virus. | | 1967 | 6060241 |
| the photosensitivity of semliki forest and other viruses. | | 1967 | 6060243 |
| assembly of semliki forest virus in brain. | | 1967 | 6066100 |
| replication of semliki forest virus: an electron microscopic study. | | 1967 | 6067298 |
| viral specific rnas in infected cells. | | 1967 | 6067598 |
| the effect of liposomal charge on the neutralizing antibody response against inactivated encephalomyocarditis and semliki forest viruses. | the primary neutralizing antibody response to encephalomyocarditis (emc) virus and semliki forest virus (sfv) is enhanced by addition of either negatively or positively charged liposomes. the purified u.v. light inactivated viruses were merely mixed with liposomes and injected intraperitoneally (i.p.) into mice. in contrast, neutral liposomes were unable to enhance the primary response to these viruses. furthermore primary immunization with inactivated sfv mixed with either neutral, positively o ... | 1984 | 6086188 |
| modulation of semliki forest virus-induced infection of mice by defective-interfering virus. | preparations of defective-interfering (di) semliki forest virus (sfv) differed qualitatively in their ability to protect mice against lethal sfv-induced encephalitis. the preparations fell into three categories: (1) di virus p13a protected the majority of mice and left them immune to subsequent challenge with 100 50% lethal doses of sfv; (2) di virus p4 protected mice to a similar extent, but the susceptibility of all surviving mice to challenge suggested that the protection was mediated without ... | 1984 | 6086774 |
| macrophages bind directly to semliki forest virus-infected cells and mediate antibody-dependent cell-mediated cytotoxicity. | macrophages were found to bind directly to semliki forest virus (sfv)-infected, but not uninfected, p815 cells. in the presence of anti-h-2d or anti-balb/c antibody, macrophages lysed sfv-infected, but not uninfected, p815 cells. it is proposed that macrophage-mediated antibody-dependent cell-mediated cytotoxicity (adcc) proceeds via two functionally distinguishable initial steps: (1) adhesion of effector to target cell, which may be mediated through antibody or through viral protein, as in the ... | 1984 | 6087780 |
| pppa2'p5a' blocks vesicular stomatitis virus replication in intact cells. | pppa2'p5'a blocked the production of infectious vesicular stomatitis virus in hela cells. when this compound was present from the beginning of infection, a selective inhibitory effect was observed in viral protein synthesis. thus, cellular translation was not affected even after 10 h of incubation with this compound, and the bulk of viral proteins was not synthesized. however, this effect was not observed with atp, gtp, or the core a2'p5'a. the step blocked by pppa2'p5'a is located early during ... | 1984 | 6090695 |
| 'impermeant' inhibitors of protein synthesis do not affect virally-infected cells as a result of a permeability change. | the effect of certain antiviral compounds said to act because of an increased permeability of virally infected cells has been tested in sfv-infected bhk cells. the time at which sfv-infected bhk cells become sensitive to the action of gppch2p is more than an hour later than the time at which protein synthesis in such cells becomes depressed. the uptake of [3h]gppch2p is the same in infected and uninfected cells, whether measured at 19 or 37 degrees c. we conclude that gppch2p, and probably other ... | 1984 | 6092318 |
| modulation of a systemic semliki forest virus infection in mice by defective interfering virus. | evidence is presented that defective interfering (di) semliki forest virus (sfv) can modulate the systemic infection in mice initiated by intraperitoneal inoculation of 10 ld50 sfv. either the mean time of death was delayed or mice failed completely to develop any sign of disease. this prophylactic activity of di virus was not due to the stimulation of an adaptive immune response since an equivalent amount of noninfectious virus antigen did not change the course of disease. | 1984 | 6092526 |
| the transfer of myristic and other fatty acids on lipid and viral protein acceptors in cultured cells infected with semliki forest and influenza virus. | [3h]myristic and [3h]palmitic acid were compared as tracers for the fatty acylation of cellular lipids and viral glycoproteins in chicken embryo cells infected with fowl plague and semliki forest virus (sfv). both of these substrates are incorporated into glycerolipids to a similar extent, whereas sphingolipids show much higher levels of palmitate than myristate after a 20 h labeling period. both fatty acid species were found to be subject to metabolic conversions into longer chain fatty acids y ... | 1984 | 6094180 |
| protection of mice infected with a lethal dose of semliki forest virus by defective interfering virus: modulation of virus multiplication. | certain defective interfering (di) semliki forest virus (sfv) preparations completely protected the majority of mice inoculated with a normally lethal dose of sfv, and the surviving mice showed no signs of disease during the period of observation. depending upon which di sfv preparation was used, the survivors were resistant to challenge with 100 ld50 sfv (di sfv p13a), or were completely sensitive (di sfv p4), the latter having evidently failed to establish a protective immunity. in this report ... | 1984 | 6094709 |
| gene order of translation of the flavivirus kunjin: further evidence of internal initiation in vivo. | the rates of inactivation of synthesis of individual virus-specified proteins by ultraviolet radiation provided an estimate of the target sizes of individual viral genes. in a control experiment with semliki forest virus, the genes for the structural proteins mapped in the known sequence 5' c-pe2-e1 3', and in accordance with initiation of translation from a single site on 26-s mrna. under the same conditions, the inactivation of synthesis of seven kunjin virus-specified proteins also followed f ... | 1984 | 6099663 |
| antihistaminics, local anesthetics, and other amines as antiviral agents. | a number of lipophilic amines of diverse chemical structure, including antihistaminics, local anesthetics, and chloroquine, were found to exhibit similar kinetics in inhibiting the infection of bhk cells by vesicular stomatitis virus. the inhibition occurred prior to both primary and secondary rna transcription but following transfer from the cell surface to an intracellular site, presumed to be the lysosomes. a similar inhibition, by these agents, of infection by sendai, influenza strain wsn, a ... | 1981 | 6115382 |
| resistance of semliki forest virus protein synthesis to high salt treatment. | selective translation of semliki forest virus-specific mrna occurred in virus-infected cells exposed to hypertonic growth medium. the selective resistance of the virus-specific protein synthesis could be detected at a wide nacl concentration range and was more significant at lowered incubation temperature (28 degrees c). it is suggested that the translation of the structural proteins encoding subgenomic 26 s rna is more resistant to the hypertonic initiation block than the translation of the gen ... | 1981 | 6118045 |
| endocytosis of enveloped animal viruses. | after attaching to the cell surface, virus particles are rapidly internalized by endocytosis and channelled into the lysosomal compartment. the endocytosis occurs by a pinocytic process involving coated pits and coated vesicles. intermediate pre-lysosomal vacuoles, termed endosomes, are recognized as a part of the intracellular pathway. our studies have shown that for several of the enveloped viruses (toga viruses, orthomyxoviruses and rhabdoviruses) the endocytic pathway is essential for produc ... | 1982 | 6129957 |
| heterospecific antiviral activity of human interferon on guinea pig endothelial cells. | human lymphoblastoid interferon has high antiviral activity on guinea pig endothelial cells. guinea pig interferon prepared in guinea pig endothelial cells protected guinea pig cells but did not give antiviral protection to human or to monkey cells. in this case, as in many others, the phenomenon is of one way crossing of the species barrier from the higher to the lower. | 1980 | 6154001 |
| carbohydrate-induced conformational changes of semliki forest virus glycoproteins determine antigenicity. | | 1980 | 6154376 |
| the influence of intramolecular disulfide bonds on the structure and function of semliki forest virus membrane glycoproteins. | | 1980 | 6154377 |
| virus-specific effects of interferon in embryonal carcinoma cells. | embryonal carcinoma (ec) cells are susceptible to infection by a variety of viruses, but do not become resistant to infection by semliki forest virus or vesicular stomatitis virus (vsv) on treatment with interferon. these observations have led to the conclusion that interferon does not induce an antiviral state in ec cells. we report here, however, that ec cells treated with interferon become resistant to infection by two picornaviruses and two ts mutants of vsv, whereas they remain sensitive to ... | 1980 | 6157099 |
| [anti-interferon action of remantadine in human lymphoblastoid cell cultures]. | | 1980 | 6158798 |
| complete nucleotide sequence of the nucleoprotein gene from the human influenza strain a/pr/8/34 (hon1). | the complete nucleotide sequence of the influenza a/pr/8/34 nucleoprotein gene was determined after cloning for dsdna copy in pbr322. the nucleoprotein gene is 1517 nucleotides long of which 1446 nucleotides code for 482 amino acids. the calculated amino acid composition is in good agreement with those published for influenza a nucleoprotein genes. the amino acid sequence of the nucleoprotein contains clusters of basic amino acids and proline, a property shared with other nucleic-acid-associated ... | 1981 | 6166474 |
| the effects of interferon and double-stranded rna upon the virus-host interaction: studies with togavirus strains in mice. | partially purified fibroblast interferon and double-stranded rna (dsrna) of fungal origin were administered as single graded doses to a2g and balb/c mice shortly before intraperitoneal infection by specified virulent or avirulent strains of representative togaviruses (semliki forest virus, venezuelan equine encephalomyelitis virus and yellow fever virus). changes of efficiency of infection arising from interference at the level of clearance or replication and changes of the expression of virulen ... | 1981 | 6168734 |
| structural complexity of defective-interfering rnas of semliki forest virus as revealed by analysis of complementary dna. | the 18s defective interfering rna of semliki forest virus has been reverse transcribed to cdna, which was shown to be heterogeneous by restriction enzyme analysis. after transformation to e.coli, using pbr322 as a vector, two clones, pkth301 and pkth309 with inserts of 1.7 kb and 2 kb, were characterized, respectively. the restriction maps of the two clones were different but suggested that both contained repeating units. at the 3' terminus, pkth301 had preserved 106 nucleotides and pkth309 102 ... | 1981 | 6169007 |
| assay of defective-interfering semliki forest virus by the inhibition of synthesis of virus-specified rnas. | we describe a simple, rapid and reproducible assay for defective-interfering semliki forest virus (di sfv) which is based on the inhibition of synthesis of virus-specified rnas in sfv-infected cells. using the assay, we have been able to show that di virus is generated by a single passage in baby hamster kidney (bhk) cells in an inoculum which contained no detectable di virus and we have calculated the u.v. target size of the interfering activity. | 1981 | 6169791 |
| concomitant methylation and synthesis in vitro of semliki forest virus (sfv) ss rnas by a fraction from infected cells. | | 1981 | 6170159 |
| comparison of specific and cross-reactive antigens of alphaviruses on virions and infected cells. | rabbit hyperimmune antisera against sindbis (sin) or semliki forest (sf) virus were absorbed with purified sin virus or sin virus-infected cells, or with sf virus or sf virus-infected cells. residual antibody titers were determined by hemagglutination inhibition (hai) and antibody-dependent, complement-mediated cytolysis (adcmc) assays. it appeared that absorption with virus-infected cells removed adcmc-detectable cross-reactive antibody much more efficiently than did absorption with either viru ... | 1982 | 6172382 |
| induction and characterization of tortoise interferon. | | 1981 | 6173590 |
| induction of interferon with low molecular weight compounds: fluorenone esters, ethers (tilorone), and pyrimidinones. | | 1981 | 6173601 |
| [effect of remantadine and ribavirin on the production and antiviral action of human interferon types i and ii]. | the results of using human interferon of types i (alpha- and beta-interferons) and ii (gamma-interferon) in combination with chemotherapeutic drugs, such as remantadin and ribavirin for the study in human cell cultures are presented. moderate doses of the drugs (25 microgram/ml) did not eliminate the interferon production. in higher doses (50 microgram/ml) they lowered the interferon production levels 2--3 times. in the presence of ribavirin the level of the interferon production lowering was hi ... | 1982 | 6174074 |
| indomethacin toxicity in the presence of interferon or interferon inducer. | | 1981 | 6175569 |
| semliki forest virus neurovirulence mutants have altered cytopathogenicity for central nervous system cells. | we have analyzed the pathogenicity and host range properties of four neurovirulence mutants of semliki forest virus which, unlike the wild type (wt), allow the survival of weanling mice injected intraperitoneally with 10(2) pfu. the mutant m9 showed a sustained multiplication in the brains of infected mice. it produced paralysis in 35%, and 8% died. demyelination occurred in 94% of the surviving mice and was associated with the destruction of oligodendrocytes. all of the mutants showed a restric ... | 1982 | 6176545 |
| cross-reactive, cell-associated antigen on l929 cells infected with temperature-sensitive mutants of sindbis virus. | temperature-sensitive (ts) mutants of sindbis virus (sin) were used to aid in the identification of alphavirus cross-reactive proteins on the surface of infected cells by antibody-dependent, complement-mediated cytolysis. antisera prepared in rabbits against purified sin or semliki forest viruses were highly cytotoxic for cells infected with wild-type sin and for cells infected at the permissive temperature with maturation-defective, ts mutants of sin belonging to several distinct complementatio ... | 1982 | 6177636 |
| in vivo hyporesponsiveness induced by sendai virus in cflp mice. | sendai and semliki forest viruses (sfv) raised the interferon (ifn) level in blood and suppressed the acute inflammatory response induced by carrageenan in cflp mice. after sendai virus had been inoculated, unresponsiveness developed to repeated challenge either with the same virus or with sfv. the hyporeactive state culminated 48 hr after first virus inoculation. it was characterized (1) by absence of ifn induction and (2) by disappearance of the virus-induced anti-inflammatory effect. in contr ... | 1982 | 6183956 |
| interferon-gamma-like molecule induces ia antigens on cultured mast cell progenitors. | persisting (p) cells (murine cells that resemble mast cells and grow continuously in vitro for prolonged periods in the presence of a specific growth factor) did not express detectable levels of ia antigens (murine class ii major histocompatibility antigens) when their growth was supported by partially purified p cell-stimulating factor. however, when these ia-negative p cells were transferred to medium conditioned by concanavalin a-stimulated spleen cells, ia antigens appeared within 24 hr. the ... | 1982 | 6184720 |
| enhancement of delayed-type hypersensitivity and induction of interferon by the lipophilic agents dda and cp-20,961. | | 1982 | 6187475 |
| interferon and antibody titrations using haemagglutinating togaviridae and trypsinized human erythrocytes. | several togaviridae of the alphavirus and flavivirus genera agglutinate trypsinized human group o erythrocytes (thoe) (shortridge and hu, 1976). haemagglutinin titers of semliki forest virus (sfv) and japanese encephalitis virus (jev) measured with thoe were equivalent to, if not higher than, those obtained with embden gander erythrocytes, even with unextracted haemagglutinin. results obtained with thoe in jev haemagglutination-inhibition tests on sera taken from a previously infected individual ... | 1983 | 6189850 |
| tunicamycin treatment inhibits the antiviral activity of interferon in mice. | earlier we reported that tunicamycin (tm) treatment of l cells in vitro significantly enhances the antiviral activity of interferon (ifn) against viruses (such as vesicular stomatitis, sindbis, and herpes simplex) which bud from membranes. however, no such enhancement of the antiviral activity of ifn by tm was observed against encephalomyocarditis virus (emcv) (nonbudding). we were interested to know whether tm would similarly enhance the antiviral activity of ifn and ifn inducers in vivo agains ... | 1983 | 6190759 |
| solubilization and immune-detection of beta-galactosidase hybrid proteins carrying foreign antigenic determinants. | three dna fragments representing almost the entire e1 gene of semliki forest virus (sfv) were inserted into a cro-lacz expression vector by oligo dc.oligo dg tailing. fragments inserted close to the 5' end of the lacz gene gave rise to hybrid proteins which were rapidly degraded. insertion of the same fragments at the 3' end, however, resulted in the synthesis of stable hybrid proteins which precipitated in an insoluble form within the bacteria. insufficient hybrid protein was soluble to allow d ... | 1983 | 6191278 |
| viral glycoproteins at different stages of intracellular transport can be distinguished using monoclonal antibodies. | monoclonal antibodies were raised against semliki forest virus (sfv) and all were found to recognize the e2 spike glycoprotein. the hybridomas were screened by immunofluorescence microscopy of infected cells to look for antibodies recognizing e2 at different stages of intracellular transport and two (9ab4 and 9ad6) were chosen for further study. immunocytochemical studies at the light and electron microscopic levels were used to show that 9ab4 recognized e2 at all stages of its transport from th ... | 1983 | 6196197 |
| studies on interferon induction and interferon sensitivity of avian reoviruses. | four strains of avian reovirus were ineffective inducers of interferon (ifn) in chicken kidney (ck) cell cultures. all strains were similar in single-cycle replication curves. at multiplicities of infection between 0.20 and 10 plaque-forming units per cell, ifn was not induced in ck cells. reovirus did not produce an ifn blocker in ck cells. attenuated reovirus did induce ifn in aged chicken embryo fibroblast (cef) cell cultures. by priming cells with a low dose of ifn before infection with reov ... | 1983 | 6197057 |
| interferon therapy in experimental semliki forest virus disease in mice. | | 1983 | 6200435 |
| increase in axonal transport in demyelinating optic nerve fibres in the mouse infected with semliki forest virus. | since the integrity of myelin and axon is closely linked with the transport of substances along the axon, changes in the fast and slow axonal transport in the demyelinating optic nerves of mice infected with semliki forest virus were studied. radioactive analysis of the superior colliculi and the optic nerves was thus made following different survival times after an intravitreal injection of tritiated proline by autoradiographic and liquid scintillation counting techniques. the amounts of both t ... | 1984 | 6202358 |
| a rapid method for the inactivation of virus infectivity prior to assay for interferons. | virus infectivity in samples of culture medium or suspensions of animal tissue which are required for interferon assay can be rapidly and conveniently inactivated by overnight incubation with beta-propiolactone (bpl). as bpl hydrolyses spontaneously samples can be assayed with no further treatment. bpl does not affect the interfering activity of alpha, beta or gamma mouse interferons. | 1984 | 6206084 |
| identification of distinct antigenic determinants on semliki forest virus by using monoclonal antibodies with different antiviral activities. | fifteen monoclonal antibodies (mas) directed against either the e1 or e2 glycoprotein of semliki forest virus (sfv) were characterized by immunoglobulin subclass, pi traject, hemagglutination inhibition, neutralization of infectious virus, and protection against virulent infection in mice. all mas except um8.4 (immunoglobulin m [igm]) belonged to various subclasses of igg and predominantly to igg2a, but all were unique as indicated by their banding patterns in isoelectric focusing. competitive b ... | 1984 | 6208379 |
| semliki forest virus penetration from endosomes: a morphological study. | the low ph dependent membrane fusion reaction responsible for the delivery of the semliki forest virus genome into the host cell for replication was visualized by electron microscopy. in order to increase the frequency at which fusion images could be detected a reversible inhibitor, ammonium chloride, was used to synchronize endosomal acidification, and 20 degrees c incubation was employed to concentrate virus particles into the endosomal compartment. | 1984 | 6240300 |
| interferon production and virus replication in lymphoblastoid cells infected with different viruses. | a semicontinuous infection system was used to test viral replication and interferon induction in lymphoblastoid cells: measles virus, newcastle disease virus (ndv), sendai virus, human parainfluenza virus (type ii and iii), semliki forest virus (sfv) and vesicular stomatitis virus (vsv). with the exception of sendai virus, all viruses replicated in the namalva cell line. only measles virus was able to induce high levels of interferon. three other cell lines, nc37, raji (tk+-variant) and raji (tk ... | 1980 | 6243928 |
| anti-viral effects of single-stranded polynucleotides against avirulent semliki forest virus infection of mice and avirulent infection of rats with encephalomyocarditis virus. | single-stranded polynucleotide preparations, which neither induce detectable interferon nor affect immune responses, suppress development of antiviral antibodies in mice infected with an avirulent strain of sfv. on a weight basis the antiviral activity of a mixture of poly(i) and poly(ho5c)-copolymer is greater than that of trna and similar antiviral effects are observed against a related virulent strain of sfv. emc virus causes and avirulent infection of rats and development of emc virus antibo ... | 1980 | 6246856 |
| antibiotics that specifically block translation in virus-infected cells. | several antibiotics including anthelmycin, blasticidin s, destomycin a, gougerotin, hygromycin b and edeine complex, known to powerfully block translation in cell-free systems, did neither inhibit protein synthesis in intact mouse l and 3t6 cells, nor in hamster bhk 21 cells, due to failure to cross the cell plasma membrane. however, after viral infection, these antibiotics exhibited a marked blockade of translation, that is related to the permeability changes induced by viral infection. the inh ... | 1980 | 6251018 |
| the effect of mouse strain on the pathogenesis of the encephalitis and demyelination induced by avirulent semliki forest virus infections. | mice from the following strains--simpson, swr/j, to, cba/ca, cw (outbred), lac/g (outbred), sjl/j and swiss a2g (outbred)--were infected i.p. with avirulent semliki forest virus. clinical signs of disease were noted, histopathological changes assessed and the blood and brain virus infectivities and serum immunoglobulin levels were measured. only the cw, to and swiss/a2g animals showed convincing evidence of demyelination at the light microscopy level but all strains developed encephalitis and mi ... | 1980 | 6252935 |
| cotranslational and posttranslational processing of viral glycoproteins. | | 1980 | 6253233 |
| humoral and cell-mediated immune mechanisms in the production of pathology in avirulent semliki forest virus encephalitis. | seven days after peripheral inoculation with an avirulent strain of semliki forest virus, the brains of cba and nude mice exhibited a mononuclear inflammation and spongiform degeneration. mice that had received cyclophosphamide (150 mg/kg) 24 h after infection showed no pathology until day 11. however, immunofluorescence studies of the brains of immunosuppressed, infected mice demonstrated viral antigen within the soma and processes of neurons at earlier periods. the brain lesions could be recon ... | 1980 | 6254882 |
| growth and release of several alphaviruses in chick and bhk cells. | the growth and release of several alphaviruses, including several strains of sindbis virus (the wild-type strain, the large plaque and small plaque variants of the hr strain, and the hr mutant ts103), semliki forest virus(sfv) and middelburg virus, and of the unrelated rhabdovirus, vesicular stomatitis virus (vsv), have been compared in chick cells and in bhk-21 cells as a function of the culture conditions for the host cell and the ionic strength of the medium. the small plaque strain of sindbi ... | 1980 | 6255069 |
| inhibition of semliki forest and herpes simplex virus production in alpha-difluoromethylornithine-treated cells: reversal by polyamines. | | 1980 | 6257550 |
| monensin and fccp inhibit the intracellular transport of alphavirus membrane glycoproteins. | temperature-sensitive mutants of semliki forest virus (sfv) and sindbis virus (sin) were used to study the intracellular transport of virus membrane glycoproteins in infected chicken embryo fibroblasts. when antisera against purified glycoproteins and (125)i- labeled protein a from staphylococcus aureus were used only small amounts of virus glycoproteins were detected at the surface of sfv ts-1 and sin ts-10 infected cells incubated at the restrictive temperature (39 degrees c). when the mutant- ... | 1980 | 6257729 |
| a subcloning strategy for dna sequence analysis. | we describe here a new strategy of fragment preparation for sequencing procedures using endlabelled dna fragments as substrates (2,3) which is directly applicable to dna fragments cloned into the pst i site of pbr322, or in modified form, to inserts into the bamh i or sal i site of the same plasmid. ordered sets of subclones of predetermined overlap are are generated. these can be sequenced directly without further strand- or fragment separation steps. | 1980 | 6258146 |
| principles for production of effective defined subunit vaccines. deduction from a model experiment. | | 1980 | 6258847 |
| development of effective subunit vaccines against enveloped viruses. | | 1980 | 6259665 |
| comparative studies of the 3'-terminal sequences of several alpha virus rnas. | | 1981 | 6259811 |
| demyelination in mice resulting from infection with a mutant of semliki forest virus. | twelve of 34 weanling mice (35%) developed lesions in the brain and spinal cord following i.p. infection with 10(2) p.f.u. of a mutant of semliki forest virus (sfv). six of 12 mice examined 13 days post infection (p.i.) showed meningo-encephalomyelitis with focal spongiform lesions in the grey and white matter. the spongiform lesions were characterised by necrosis of putative oligodendrocytes, myelinic vacuolation and mononuclear cell infiltration. only one of six mice examined 21 days p.i. and ... | 1981 | 6259872 |
| ph-dependent hemolysis by influenza, semliki, forest virus, and sendai virus. | | 1981 | 6261454 |
| [alphavirus reproduction in cultures of transplantable human lymphoblastic cells in acute infection]. | the results of investigations of acute infection of continuous human b- and t-cells with typical members of the alphavirus group--semliki forest, sindbis, and venezuelan equine encephalomyelitis viruses, are presented. virus amplification was shown to pass through the typical phases: eclipse, logarithmic growth, plateau. infectious virus production per one cell was from 10 to 10,000 pfu in various cultures. cell infection results in interferon production. replication of the viruses under study i ... | 1980 | 6261461 |
| cell fusion by semliki forest, influenza, and vesicular stomatitis viruses. | representatives of three families of enveloped viruses were shown to fuse tissue culture cells together. these were: semliki forest virus (sfv, a togavirus), vesicular stomatitis virus (a rhabdovirus), and two myxoviruses, fowl plaque virus and japan influenza virus (japan)/a/305/57). unlike paramyxoviruses, whose fusion activity is known to occur over a broad ph range, fusion by these viruses was restricted to mildly acidic ph. the ph thresholds for the four viruses were 6.0, 6.1, 5.5, and 5.1, ... | 1981 | 6265470 |
| metastatic tumor cell variants with increased resistance to infection by semliki forest virus. | semliki forest virus (sfv) is an interesting virus for cell interaction studies because it binds directly to the cells' major histocompatibility antigens. we used this reagent to study the expression and functional properties of h-2 molecules on murine tumor lines that are closely related but differ greatly in metastatic capacity. tumor cell variants with high metastatic capacity showed an increased resistance to virus infection, an effect that was selective for sfv. although the high metastatic ... | 1981 | 6267134 |
| modification of membrane permeability induced by animal viruses early in infection. | | 1981 | 6267801 |
| benzoxazolone-5-sulphonanilides, 1-(benzoxazolone-5'-sulphonyl)-benzotriazoles and 4-hydroxy-3,2'-diaminobenzenesulphonanilides with antiviral activity. | benzoxazolone-5-(2'-nitro)-sulphonanilides were synthesized by acylation of o-nitroanilines with benzoxazolone-5-sulphochloride or 3-methylbenzoxazolone-5-sulphochloride. the nitro group in these compounds was subjected to reduction and the resulting amino derivatives were cyclysed to yield the corresponding 1-(benzoxazolone-5'-sulphonyl)-benzotriazoles. decyclization of the oxazolone cycle of benzoxazolone-5-(2'-amino)-sulphonanilides resulted in 4-hydroxy-3,2'-diaminobenzenesulphonanilides. in ... | 1981 | 6268120 |
| antibody response to spike protein vaccines prepared from semliki forest virus. | subunit vaccines, containing the spike glycoproteins of semliki forest virus (sfv) in three different forms, have been prepared: detergent-solubilized monomers, detergent- and lipid-free octamers, and virosomes in which the spike proteins are reconstituted into phospholipid vesicles. previous studies have shown that the octamers and the virosomes are very efficient in protecting mice against the encephalitis caused by virulent sfv (morein, et al., 1978). in this study we have characterized the s ... | 1981 | 6268742 |
| cellular synthesis and modification of murine hepatitis virus polypeptides. | mouse l fibroblasts infected with mouse hepatitis virus, mhv3, and radiolabelled with 35s-methionine, contained, in addition to the three major structural polypeptides, p24, p56 and p180, two additional ones, p22 and p50. of these total five polypeptides, only three, p22, p56 and p180, were labelled in infected cells during a 2 min 35s-methionine pulse and are, therefore, presumed to be immediate translation products. pulse-chases and chymotryptic peptide mapping experiments showed apparent prec ... | 1981 | 6270250 |
| [biogenesis of viral glycoproteins and role of sugar chains in biological functions of virus (author's transl)]. | | 1981 | 6276923 |
| construction of a hybrid plasmid molecule containing the total coding region of semliki forest virus 26s mrna. | we have constructed a hybrid plasmid molecule that contains the complete coding sequences from the 26s mrna of semliki forest virus. five fragments which together covered the mrna sequence were isolated from three original hybrid plasmids and joined together at five different restriction endonuclease cleavage sites using t4 dna ligase. | 1982 | 6278065 |
| [morphological study of a mixed alphavirus infection]. | in combined paired cultivation of 8 venezuelan equine encephalomyelitis virus, multiploid virions formed in 17.8% of cases. five clones with this effect were used in mixed infections with clones of semliki forest and sindbis viruses. in these infections changes in virions of the virus progeny were observed in 20% and 16.6%, respectively. mixed cultivation of pairs of sindbis and semliki forest viruses resulted in formation of multiploid virions in 42.8%. besides, in two mixed populations formed ... | 1981 | 6278779 |
| uncoating of enveloped viruses. | | 1982 | 6279312 |
| roles of polyamines in the replication of animal viruses. | several animal viruses are known to contain significant amounts of polyamines but so far the function of these viral components is poorly understood. in this study the role of polyamines in the replication of two different types of viruses, herpes simplex virus type 2 and semliki forest virus (sfv) has been investigated. purified sfv was found to contain fairly small amounts of polyamines, sufficient to neutralize only about 3% of viral nucleic acid phosphate, i.e., 1/20 of that found in herpes ... | 1981 | 6279979 |
| demyelination induced in mice by avirulent semliki forest virus. i. virology and effects on optic nerve. | swiss a2g mice were infected intraperitoneally with an avirulent strain of semliki forest virus. the virus titres in the optic nerves, retina and brain were estimated on post-inoculation days 3 to 8. high titres of virus were obtained in the optic nerve, retina and brain. the optic nerves, retina and brain were studied by light microscopy up to post-inoculation day 67. electron microscope studies wee carried out on the optic nerve on post-inoculation days 11 and 14. inflammatory, microcystic cha ... | 1982 | 6280088 |
| demyelination induced in mice by avirulent semliki forest virus. ii. an ultrastructural study of focal demyelination in the brain. | four-week-old mice were infected intraperitoneally with an avirulent strain a7(74) of semliki forest virus (sfv) and killed at 4, 10, 15, 21 and 29 days after inoculation. focal demyelinating lesions were present by 10 days. these were usually accompanied by a mononuclear infiltrate which included lymphocytes possessing characteristic cytoplasmic projections. these latter extended deep into the cytoplasm of adjacent cells, which were usually astrocytes and macrophages. other features of the foca ... | 1982 | 6280089 |
| immunoglobulin synthesis in nude (nu/nu), nu/+ and reconstituted nu/nu mice infected with a demyelinating strain of semliki forest virus. | infections with the avirulent (a7/74) strain of semliki forest virus which causes primary demyelination of the central nervous system in mice have been studied further in nude athymic (nu/nu) mice and their immunocompetent (nu/+) litter mates to measure the production of immunoglobulins. this has been done by radial immunodiffusion and enzyme-linked immunosorbent assays. half the nude mice examined were able to synthesize specific igg but at levels 1,000-fold lower than their nu/+ littermates. t ... | 1982 | 6280913 |
| properties of monoclonal antibodies directed against the glycoproteins of sindbis virus. | four monoclonal antibodies that react with sindbis virus glycoproteins have been examined for (i) their effects on virus infectivity, (ii) their ability to recognize conformational changes in glycoprotein structure, and (iii) their cross-reaction with several different alphaviruses. two of the monoclonal antibodies reacted with the native forms of the e1 glycoprotein but did not neutralize virus infectivity. one of the anti-e1 antibodies formed an infectious virus-antibody complex. the other two ... | 1982 | 6281377 |
| are lysosomes a site of enveloped-virus penetration? | | 1982 | 6286223 |
| the effect of defective-interfering semliki forest virus on the histopathology of infection with virulent semliki forest virus in mice. | the majority of mice inoculated with a mixture of a lethal dose of virulent semliki forest virus (sfv) strain ts+ and defective-interfering (di) sfv remained completely health, with virus infectivity levels in brain tissue reduced by 99.9%. the results of previous studies had suggested that these effects were primarily the result of the intrinsic interfering capacity of di virus rather than of host defense responses. because sfv strain ts+ and an avirulent strain of sfv have clearly distinguisha ... | 1982 | 6286798 |
| interferon induction by 5-halo-6-phenyl pyrimidinones. | the interferon inducing characteristics of a new series of 6-phenyl pyrimidinol compounds are described and compared against a previously identified pyrimidine, 2-amino-5-bromo-6-methyl-4-pyrimidinol (abmp). interestingly, a split in ability to induce interferon but not in vivo antiviral activity was observed in the newest compounds. one representative compound, 2-amino-5-bromo-6-phenyl-4-pyrimidinol (abpp) induced high levels of serum interferon in mice, cats and cattle in vivo and human lympho ... | 1980 | 6286802 |
| translation of capped virus mrna in encephalomyocarditis virus-infected cells. | the pattern of protein synthesis in hela cells simultaneously infected with encephalomyocarditis virus (emcv) and semliki forest virus (sfv) has been analysed throughout the time course of the infection. the ratio of the picornavirus protein gamma versus the togavirus late protein c increased when the m.o.i. of emcv was raised, and the ratio of c/gamma increased with higher multiplicities of sfv. under some conditions, the co-infected cells simultaneously synthesized the picornavirus and togavir ... | 1982 | 6286854 |
| ultraviolet-irradiated vesicular stomatitis virus and defective-interfering particles are similar non-specific inhibitors of virus infection. | the way in which ultraviolet-irradiated vesicular stomatitis virus (vsv) inhibits the early events in vsv infection has been further characterized. comparison of several different u.v.-irradiated thermolabile, temperature-sensitive mutants before and after heat inactivation established a requirement for inhibitory activity of functional g, n and l proteins, but not m protein. defective-interfering (di) particles, whether irradiated or not, inhibited vsv primary transcription as efficiently as uv ... | 1982 | 6286855 |
| membrane changes during viral infection. | the effect of viruses on the surface membrane of susceptible cells during the entry and exit process has been studied. haemolytic paramyxoviruses induce a non-specific leakage to low-molecular-weight compounds during entry; other viruses do not show this effect. during exit, no such changes occur with any virus so far studied: some viruses are released without any obvious change at all in surface membrane function; in other cases, uptake of some nutrients is altered and there is a fall in membra ... | 1982 | 6291665 |
| virus titres and persistently raised white cell counts in cerebrospinal fluid in mice after peripheral infection with demyelinating semliki forest virus. | | 1982 | 6294545 |
| experimental allergic encephalomyelitis: modification of optic nerve pathology by antecedent virus infection. | | 1982 | 6295047 |
| lysosomal enzyme changes in macrophages from mice given myocrisin and infected with avirulent semliki forest virus. | myocrisin given to mice i.p. causes depression of lysosomal enzyme activity (acid phosphatase, beta-glucuronidase and n-acetyl-beta-d-glucosaminidase) in peritoneal macrophages. if avirulent semliki forest virus (sfv) is given i.p. 3 h after the myocrisin, further depression of lysosomal enzyme activity occurs, a very high titre of virus is produced in these macrophages and the virus becomes lethal, causing 100% mortality. the possible interrelationships between depressed lysosomal activity, hig ... | 1982 | 6295431 |
| effect of alphavirus infection on mouse embryos. | seven strains and mutants of the alphaviruses, semliki forest virus and sindbis virus, differed in their lethality for mouse embryos and their mothers. the a7 strain and the neurovirulence mutant m103 of semliki forest virus were selected for detailed comparison. a7 produced 100% lethality of mouse embryos but was avirulent for their mothers. m103 did not kill embryos or their mothers but did induce postnatal immunity. this immunity could be induced in utero or by suckling to an immune mother. i ... | 1982 | 6295945 |
| blood brain barrier disturbance and immunoglobulin g levels in the cerebrospinal fluid of the mouse following peripheral infection with the demyelinating strain of semliki forest virus. | immunoglobulin g and albumin levels have been measured in the cerebrospinal fluid and serum of swiss a2g mice following single intraperitoneal inoculation of semliki forest virus. this strain of virus used causes a meningoencephalitis followed by immunologically-mediated demyelination. by the use of the levels of immunoglobulin g and albumin in cerebrospinal fluid and serum to calculate the cerebrospinal fluid: serum ratios and the cerebrospinal fluid immunoglobulin g index, it has been shown th ... | 1982 | 6298371 |
| xyloadenosine analogue of (a2'p)2a inhibits replication of herpes simplex viruses 1 and 2. | molecules of the structure ppp(a2'p)2a containing a 2' leads to 5' phosphodiester bond, commonly abbreviated as 2-5a, are synthesized in interferon-treated virally-infected cells and have been implicated in several systems as contributing to interferon's antiviral activity. the 2-5a binds to and subsequently activates an endogenous endonuclease, ultimately resulting in degradation of rna. we have been interested in the use of 2-5a analogues to achieve antiviral activity without the use of interf ... | 1983 | 6300696 |
| reconstitution of semliki forest virus infected mice, induces immune mediated pathological changes in the cns. | reconstitution of semliki forest virus infected nude mice with spleen cells from their immunocompetent nu/+ litter mates resulted in an abolition of the otherwise persistent brain virus, production of anti-sfv igg, and development of normally absent brain pathology. the brain pathological changes, including demyelination, seem to be mediated by t cells, and are maximum 14 days after sensitization of the reconstituting spleen cells. sensitization of the spleen cells 7 days before transfer to the ... | 1983 | 6305540 |
| effect of vesicular stomatitis virus and semliki forest virus on uptake of nutrients and intracellular cation concentration. | bhk-21 cells showed an increased ability to concentrate 2-deoxy-d-glucose (dglc) 2 to 3 h after infection with vesicular stomatitis virus (vsv) or semliki forest virus (sfv), which began to be released at 2 and 3 h post-infection respectively; uptake of other nutrients was not affected in this way. intracellular na+ was either unchanged (vsv-infected cells) or increased (sfv-infected cells); k+ content was unchanged. these results do not support the current hypothesis that a non-specific increas ... | 1983 | 6306146 |
| combined treatment of mice with panax ginseng extract and interferon inducer. amplification of host resistance to semliki forest virus. | | 1983 | 6306707 |
| nucleic acid sandwich hybridization in adenovirus diagnosis. | | 1983 | 6307597 |
| interaction of enveloped viruses with planar bilayer membranes: observations on sendai, influenza, vesicular stomatitis, and semliki forest viruses. | exposure of a planar lipid bilayer to sendai virus at ph 7.0 resulted in conductance increases that continued over several minutes, provided that the virus particles had first been conditioned by freezing and thawing, sonicating, or storing for 2 weeks in the cold. individual electrical events could not be resolved, even on a millisecond time scale, and thus do not reflect the insertion of structural channels into the lipid bilayer. prior treatment of the sendai virions with protease prevented t ... | 1983 | 6308891 |
| ross river virus 26 s rna: complete nucleotide sequence and deduced sequence of the encoded structural proteins. | the complete sequence of the 26 s rna of ross river virus (t48 strain) has been obtained and from this the amino acid sequences of the encoded structural proteins have been deduced. these include a basic capsid protein and two envelope glycoproteins. the nucleotide sequence was obtained by chemical sequence analysis of both single-stranded and double-stranded cdna made to rna and the sequence data so obtained was rapidly aligned by making use of the protein homology found among the alphaviruses. ... | 1983 | 6310876 |