bluuebunny/crossref_metadata_2025 huggingface dataset:
Betanodavirus infection in the freshwater model fish medaka (Oryzias latipes)
Authors: Furusawa Ryo , Okinaka Yasushi , Nakai Toshihiro
Published: July 2006

Betanodaviruses, the causal agents of viral nervous necrosis in marine fish, have bipartite, positive-sense RNA genomes. As their genomes are the smallest and simplest among viruses, betanodaviruses have been studied in detail as model viruses by using a genetic-engineering system, as has occurred with the insect alphanodaviruses, the other members of the family Nodaviridae. However, studies of virus–host interactions have been limited, as betanodaviruses basically infect marine fish at early developmental stages (larval and juvenile). These fish are only available for a few months of the year and are not suitable for the construction of a reverse-genetics system. To overcome these problems, several freshwater fish species were tested for their susceptibility to betanodaviruses. It was found that adult medaka (Oryzias latipes), a well-known model fish, was susceptible to both Striped jack nervous necrosis virus (the type species of the genus Betanodavirus) and Redspotted grouper nervous necrosis virus (RGNNV), which have different host specificities in marine fish species. Infected medaka exhibited erratic swimming and the viruses were localized specifically in the brain, spinal cord and retina of the infected fish, similar to the pattern of infection in naturally infected marine fish. Moreover, medaka were susceptible to RGNNV at the larval stage. This is the first report of a model virus–model host infection system in fish. This system should facilitate elucidation of the mechanisms underlying RNA virus infections in fish.
The Pro78 residue regulates the capacity of the human immunodeficiency virus type 1 Nef protein to inhibit recycling of major histocompatibility complex class I molecules in an SH3-independent manner
Authors: Casartelli Nicoletta , Giolo Giorgia , Neri Francesca , Haller Claudia , Potestà Marina , Rossi Paolo , Fackler Oliver T. , Doria Margherita
Published: July 2006

The Nef protein is a crucial pathogenicity factor of human immunodeficiency virus type 1 (HIV-1) that contains a proline-rich motif consisting of four conserved prolines: Pro69 (P69), P72, P75 and P78. P72 and P75 were shown to bind Src homology domains 3 (SH3) and have been implicated in many biological functions of Nef, including downmodulation of cell-surface major histocompatibility complex class I (MHC-I). P78 is involved together with P69 in positioning of the Nef–SH3 complex and it has been shown to be essential for Nef activity of MHC-I downmodulation. It is shown here that alteration of P78 affects recycling of MHC-I molecules to the cell surface, but does not interfere with SH3 binding. In addition, it is demonstrated that P72 and P75, and thus the SH3-binding capacity, are fully dispensable for Nef activity on MHC-I.
Diversity of the population of Tick-borne encephalitis virus infecting Ixodes ricinus ticks in an endemic area of central Switzerland (Canton Bern)
Authors: Casati Simona , Gern Lise , Piffaretti Jean-Claude
Published: July 2006

Tick-borne encephalitis virus (TBEV), a member of the genus Flavivirus, has a positive-strand RNA genome containing a single open reading frame flanked by non-coding regions (NCRs). Ixodes ricinus ticks (n=307) were collected from vegetation in a natural TBEV focus in Belp, Switzerland. The presence and identity of the virus were determined by nested RT-PCR followed by sequencing of the 5′-terminal region that comprises the 5′ NCR and the capsid-encoding region (C). The presence of the western European TBEV subtype (W-TBEV) genome was detected in 14.3 % of the ticks. Nucleotide sequence analysis revealed a high variability of 55.5 %. In particular, four DNA fragments (CS ‘A’, CS ‘B’, the folding-stem structure and the start codon) showed substantial heterogeneity, which has the potential of compromising replication, translation and packaging of the viral genome. This variability may reflect a viral strategy to select the fittest RNA molecule to produce a viral infection in the different vertebrate hosts that may be encountered by the ticks. It may also indicate a possible ancient introduction of TBEV to the Belp site. In addition, it may contribute to explaining the annual low incidence of tick-borne encephalitis in the natural focus of Belp, despite the high prevalence of TBEV genomes in ticks.
Inhibition of SUMO-independent PML oligomerization by the human cytomegalovirus IE1 protein
Authors: Kang Heejung , Kim Eui Tae , Lee Hye-Ra , Park Jung-Jin , Go Yoon Young , Choi Cheol Yong , Ahn Jin-Hyun
Published: July 2006

In human cytomegalovirus-infected cells, the immediate-early IE1 protein disrupts the subnuclear structures known as the PML oncogenic domains or PODs, via the induction of PML desumoylation. This activity correlates with the functions of IE1 in transcriptional regulation and in the stimulation of lytic infection. Here, the effects of IE1 in induction of desumoylation of PML were characterized. IE1 did not interfere with the formation of sumoylated forms of PML in vitro. In in vitro assays using the sumoylated proteins, a SUMO-specific protease SENP1 desumoylated both PML and IE1. However, the IE1 proteins generated from bacteria or insect cells were unable to desumoylate PML in the same conditions. Although both IE1 and SUMO proteases such as SENP1, Axam and SuPr-1 efficiently desumoylated PML in co-transfection assays, they exerted different effects on the localization of PML. In cells transfected with either SENP1 or SuPr-1, the number of PML foci was reduced significantly and these remnant PML foci were devoid of SUMO-1 signals. However, in cells co-transfected with both SUMO proteases and IE1, these SUMO-independent PML foci were also completely disrupted. Furthermore, IE1, but not SENP1, was shown to disrupt the PML foci generated via transfection of a sumoylation-deficient mutant of PML. These data suggest that IE1 exhibits neither an inhibitory effect on sumoylation of PML nor intrinsic SUMO protease activity against PML in vitro. The finding that IE1 is capable of disrupting SUMO-independent PML aggregates suggests that inhibition of PML oligomerization by IE1 may play an important role in inducing PML desumoylation in vivo.
Functional analysis of the five melon necrotic spot virus genome-encoded proteins
Authors: Genovés A. , Navarro J. A. , Pallás V.
Published: July 2006

Function of the melon necrotic spot virus (MNSV) genome-encoded proteins (p29, p89, p7A, p7B and p42) has been studied. Protein-expression mutants of an infectious, full-length cDNA clone of a Spanish MNSV-Al isolate and a recombinant green fluorescent protein (GFP)-expressing virus were used in infection bioassays on melon plants. Results revealed that p29 and p89 are both essential for virus replication, whereas small proteins p7A and p7B are sufficient to support viral movement between adjacent cells operating in trans. It is also demonstrated that, in addition to its structural role as coat protein, p42 is an important factor controlling symptoms and is required for systemic transport. Moreover, both p42 and p7B, among all of the MNSV-encoded proteins, were able to delay RNA silencing in transient-expression assays on GFP-transgenic Nicotiana benthamiana plants. Finally, the presence of p42 also produced an enhancing effect on local spread similar to that of potyviral helper component proteinase (HC-Pro), probably due to its RNA silencing-suppression ability.
Porcine reproductive and respiratory syndrome virus-infected alveolar macrophages contain no detectable levels of viral proteins in their plasma membrane and are protected against antibody-dependent, complement-mediated cell lysis
Authors: Costers Sarah , Delputte Peter L. , Nauwynck Hans J.
Published: July 2006

Porcine reproductive and respiratory syndrome virus(PRRSV) can evade the host immune system, which results in prolonged virus replication for several weeks to several months. To date, the mechanisms of PRRSV immune evasion have not been investigated in detail. One possible immune-evasion strategy is to avoid incorporation of viral proteins into the plasma membrane of infected cells, as this prevents recognition by virus-specific antibodies and consequent cell lysis either by the classical complement pathway or by antibody-dependent, cell-mediated cytotoxicity. In this study, viral proteins were not observed in the plasma membrane ofin vitro-infected macrophages by using confocal microscopy or flow cytometry. Subsequently, the sensitivity of PRRSV-infected macrophages towards antibody-dependent, complement-mediated cell lysis (ADCML) was determined by using an ADCML assay. A non-significant percentage of PRRSV-infected cells were killed in the assay, showing thatin vitroPRRSV-infected macrophages are protected against ADCML. PRRSV proteins were not detected in the plasma membrane ofin vivo-infected alveolar macrophages and ADCML was also not observed. Together, these data indicate that viral proteins are not incorporated into the plasma membrane of PRRSV-infected macrophages, which makes infected cells invisible to PRRSV-specific antibodies. This absence of viral proteins on the cell surface could explain the protection against ADCML observed forin vitroandin vivoPRRSV-infected macrophages, and may play a role in virus persistence.
Orchid fleck virus is a rhabdovirus with an unusual bipartite genome
Authors: Kondo Hideki , Maeda Takanori , Shirako Yukio , Tamada Tetsuo
Published: July 2006

Orchid fleck virus (OFV) has an unusual bipartite negative-sense RNA genome with clear sequence similarities to those of nucleorhabdoviruses. The OFV genome consists of two single-stranded RNA molecules, RNA1 and RNA2 that are 6413 and 6001 nt long, respectively, with open reading frame (ORF) information in the complementary sense. RNA1 encodes 49 (ORF1), 26 (ORF2), 38 (ORF3), 20 (ORF4) and 61 kDa (ORF5) proteins, and RNA2 encodes a single protein of 212 kDa (ORF6). ORF1, ORF5 and ORF6 proteins had significant similarities (21–38 % identity) to the nucleocapsid protein (N), glycoprotein (G) and polymerase (L) gene products, respectively, of other rhabdoviruses, especially nucleorhabdoviruses, whereas ORF2, ORF3 and ORF4 proteins had no significant similarities to other proteins in the international databases. Similarities between OFV and rhabdoviruses were also found in the sequence complementarity at both termini of each RNA segment (the common terminal sequences are 3′-UGUGUC---GACACA-5′), the conserved intergenic sequences and in being negative sense. It was proposed that a new genus Dichorhabdovirus in the family Rhabdoviridae of the order Mononegavirales should be established with OFV as its prototype member and type species.
Infectivity variation and genetic diversity among strains of Western equine encephalitis virus
Authors: Nagata Les P. , Hu Wei-Gang , Parker Michael , Chau Damon , Rayner George A. , Schmaltz Fay L. , Wong Jonathan P.
Published: July 2006

Variation in infectivity and genetic diversity in the structural proteins were compared among eight strains of Western equine encephalitis virus (WEEV) to investigate WEEV virulence at the molecular level. A lethal intranasal infectivity model of WEEV was developed in adult BALB/c mice. All eight strains examined were 100 % lethal to adult mice in this model, but they varied considerably in the time to death. Based on the time to death, the eight strains could be classified into two pathotypes: a high-virulence pathotype, consisting of strains California, Fleming and McMillan, and a low-virulence pathotype, comprising strains CBA87, Mn548, B11, Mn520 and 71V-1658. To analyse genetic diversity in the structural protein genes, 26S RNAs from these eight strains were cloned and sequenced and found to have >96 % nucleotide and amino acid identity. A cluster diagram divided the eight WEEV strains into two genotypes that matched the pathotype grouping exactly, suggesting that variation in infectivity can be attributed to genetic diversity in the structural proteins among these eight strains. Furthermore, potential amino acid differences in some positions between the two groups were identified, suggesting that these amino acid variations contributed to the observed differences in virulence.
Hepatitis C virus polyprotein vaccine formulations capable of inducing broad antibody and cellular immune responses
Authors: Vajdy Michael , Selby Mark , Medina-Selby Angelica , Coit Doris , Hall John , Tandeske Laura , Chien David , Hu Celine , Rosa Domenico , Singh Manmohan , Kazzaz Jina , Nguyen Steve , Coates Steve , Ng Philip , Abrignani Sergio , Lin Yin-Ling , Houghton Michael , O'Hagan Derek T.
Published: July 2006

Although approximately 3 % of the world's population is infected withHepatitis C virus(HCV), there is no prophylactic vaccine available. This study reports the design, cloning and purification of a single polyprotein comprising the HCV core protein and non-structural proteins NS3, NS4a, NS4b, NS5a and NS5b. The immunogenicity of this polyprotein, which was formulated in alum, oil-in-water emulsion MF59 or poly(dl-lactide co-glycolide) in the presence or absence of CpG adjuvant, was then determined in a murine model for induction of B- and T-cell responses. The addition of adjuvants or a delivery system to the HCV polyprotein enhanced serum antibody and T-cell proliferative responses, as well as IFN-γresponses, by CD4+T cells. The antibody responses were mainly against the NS3 and NS5 components of the polyprotein and relatively poor responses were elicited against NS4 and the core components. IFN-γresponses, however, were induced against all of the individual components of the polyprotein. These data suggest that the HCV polyprotein delivered with adjuvants induces broad B- and T-cell responses and could be a vaccine candidate against HCV.
Functional replacement of the R region of simian immunodeficiency virus-based vectors by heterologous elements
Authors: Brandt Sabine , Grunwald Thomas , Lucke Susann , Stang Alexander , Überla Klaus
Published: July 2006

Substitution of lentiviralcis-acting elements by heterologous sequences might allow the safety of lentiviral vectors to be enhanced by reducing the risk of homologous recombination and vector mobilization. Therefore, a substitution and deletion analysis of the R region of simian immunodeficiency virus (SIV)-based vectors was performed and the effect of the modifications on packaging and transfer by SIV and human immunodeficiency virus type 1 (HIV-1) particles was analysed. Deletion of the first 7 nt of R reduced vector titres by 10- to 20-fold, whilst deletion of the entire R region led to vector titres that were 1500-fold lower. Replacement of the R region of SIV-based vectors by HIV-1 or Moloney murine sarcoma virus R regions partially restored vector titres. A non-retroviral cellular sequence was also functional, although to a lesser extent. In the absence oftat, modification of the R region had only minor effects on cytoplasmic RNA stability, steady-state levels of vector RNA and packaging, consistent with the known primary function of R during reverse transcription. Although the SIV R region of SIV-based vectors could be replaced functionally by heterologous sequences, the same modifications of R led to a severe replication defect in the context of a replication-competent SIV. As SIV-based vectors containing the HIV-1 R region were transferred less efficiently by HIV-1 particles than wild-type SIV vectors, a match between R andcis-acting elements of the vector construct seems to be more important than a match between R and the Gag or Pol proteins of the vector particle.
Identification of an RNA-silencing suppressor in the genome of Grapevine virus A
Authors: Zhou Z. Sh. , Dell'Orco M. , Saldarelli P. , Turturo C. , Minafra A. , Martelli G. P.
Published: July 2006

Higher plants use post-transcriptional gene silencing (PTGS), an RNA-degradation system, as a defence mechanism against viral infections. To counteract this, plant viruses encode and express PTGS suppressor proteins. Four of the five proteins encoded by the Grapevine virus A (GVA) genome were screened using a green fluorescent protein (GFP)-based transient expression assay, and the expression product of ORF5 (protein p10) was identified as a suppressor of silencing. ORF5 p10 suppressed local and systemic silencing induced by a transiently expressed single-stranded sense RNA. This protein was active towards both a transgene and exogenous GFP mRNAs. Ectopic expression of GVA-ORF5 by a Potato virus X vector enhanced symptom severity. The findings that p10 markedly reduces the levels of small interfering RNAs (siRNAs) and that the recombinant protein is able to bind single-stranded and double-stranded forms of siRNAs and microRNAs, suggest the existence of a potential mechanism of suppression based on RNA sequestering.
Analysis of human and swine hepatitis E virus (HEV) isolates of genotype 3 in Japan that are only 81–83 % similar to reported HEV isolates of the same genotype over the entire genome
Authors: Inoue Jun , Takahashi Masaharu , Ito Keiichi , Shimosegawa Tooru , Okamoto Hiroaki
Published: July 2006

Full-length sequences were determined for a human hepatitis E virus (HEV) isolate (HE-JA04-1911) and two swine HEV isolates (swJ8-5 and swJ12-4) that belong to one of three clusters within genotype 3 in Japan and are close to Spanish isolates according to their partial sequences. The three HEV isolates were 89.7–92.9 % identical to each other, but only 80.7–83.0 % similar to 21 HEV strains of the same genotype isolated in Canada, Kyrgyzstan, the USA and Japan over their entire genome. On comparison with HEV isolates whose partial sequence is known, the HE-JA04-1911, swJ8-5 and swJ12-4 isolates segregated into a phylogenetic cluster consisting of human and swine HEV isolates in Japan and the UK, with identities of 89.8–100 % and 87.9–92.4 %, respectively. Genotype 3 HEV isolates were found to be markedly heterogeneous. The UK-isolate-like HEV strains in Japan may have originated from the UK via the importation of pigs since 1900.
Response of immunocompetent and immunosuppressed Spodoptera littoralis larvae to baculovirus infection
Authors: Rivkin Hadassah , Kroemer Jeremy A. , Bronshtein Alexander , Belausov Eduard , Webb Bruce A. , Chejanovsky Nor
Published: July 2006

The Mediterranean lepidopteran pest Spodoptera littoralis is highly resistant to infection with the Autographa californica multiple nucleopolyhedrovirus (AcMNPV) via the oral route, but highly sensitive to infection with budded virus (BV) via the intrahaemocoelic route. To study the fate of AcMNPV infection in S. littoralis, vHSGFP, an AcMNPV recombinant that expresses the reporter green fluorescent protein gene under the control of the Drosophila heat-shock promoter, and high-resolution fluorescence microscopy were utilized. S. littoralis fourth-instar larvae infected orally with vHSGFP showed melanization and encapsulation of virus-infected tracheoblast cells serving the midgut columnar cells. At 72 h post-infection, the viral foci were removed during the moult clearing the infection. Thus, oral infection was restricted by immune responses to the midgut and midgut-associated tracheal cells. By contrast, injection of BV into the haemocoel resulted in successful infection of tracheoblasts, followed by spread of the virus through the tracheal epidermis to other tissues. However, in contrast to fully permissive infections where tracheoblasts and haemocytes are equally susceptible to infection, a severe limitation to vHSGFP infection of haemocytes was observed. To investigate the resistance of S. littoralis haemocytes to BV infection with AcMNPV, the larval immune system was suppressed with the Chelonus inanitus polydnavirus or a putatively immunosuppressive polydnavirus gene, P-vank-1. Both treatments increased the susceptibility of S. littoralis larvae to AcMNPV. It is concluded that the resistance of S. littoralis to AcMNPV infection involves both humoral and cellular immune responses that act at the gut and haemocyte levels. The results also support the hypothesis that tracheolar cells mediate establishment of systemic baculovirus infections in lepidopteran larvae. The finding that polydnaviruses and their encoded genes synergize baculovirus infection also provides an approach to dissecting the responses of the lepidopteran immune system to viruses by using specific polydnavirus immunosuppressive genes.
Human herpesvirus 1 protein US3 induces an inhibition of mitochondrial electron transport
Authors: Derakhshan Mohammad , Willcocks Margaret M. , Salako Michael A. , Kass George E. N. , Carter Michael J.
Published: July 2006

Previous studies have identified virus proteins that traffic to mitochondria and may affect mitochondrial function. Here, it is reported that Human herpesvirus 1 (HHV-1, herpes simplex virus 1) and influenza virus reduced mitochondrial respiration, whilst Measles virus, cytomegalovirus, coxsackievirus B4 and Feline calicivirus did not. The inhibition of total cellular respiration was caused by a block in the mitochondrial electron-transport chain. This effect occurred during β-phase protein synthesis and the inhibition of mitochondrial respiration could be reproduced by ectopic expression of the β-phase protein US3. An HHV-1 mutant lacking this protein failed to inhibit oxygen consumption in infected cells relative to controls. It was concluded that US3 was mediating the suppression of mitochondrial respiration following HHV-1 infection. The integrity of the electron-transport chain in HHV-1-infected cells was analysed further and the site of the block in electron transport was located between complexes II and III, a site previously shown to be affected by Poliovirus.
Novel replication-incompetent adenoviral B-group vectors: high vector stability and yield in PER.C6 cells
Authors: Havenga M. , Vogels R. , Zuijdgeest D. , Radosevic K. , Mueller S. , Sieuwerts M. , Weichold F. , Damen I. , Kaspers J. , Lemckert A. , van Meerendonk M. , van der Vlugt R. , Holterman L. , Hone D. , Skeiky Y. , Mintardjo R. , Gillissen G. , Barouch D. , Sadoff J. , Goudsmit J.
Published: July 2006

Adenoviral vectors based on adenovirus type 35 (rAd35) have the advantage of low natural vector immunity and induce strong, insert-specific T- and B-cell responses, making them prime-candidate vaccine carriers. However, severe vector-genome instability of E1-deleted rAd35 vectors was observed, hampering universal use. The instability of E1-deleted rAd35 vector proved to be caused by low pIX expression induced by removal of the pIX promoter, which was located in the E1B region of B-group viruses. Reinsertion of a minimal pIX promoter resulted in stable vectors able to harbour large DNA inserts (>5 kb). In addition, it is shown that replacement of the E4-Orf6 region of Ad35 by the E4-Orf6 region of Ad5 resulted in successful propagation of an E1-deleted rAd35 vector on existing E1-complementing cell lines, such as PER.C6 cells. The ability to produce these carriers on PER.C6 contributes significantly to the scale of manufacturing of rAd35-based vaccines. Next, a stable rAd35 vaccine was generated carrying Mycobacterium tuberculosis antigens Ag85A, Ag85B and TB10.4. The antigens were fused directly, resulting in expression of a single polyprotein. This vaccine induced dose-dependent CD4+ and CD8+ T-cell responses against multiple antigens in mice. It is concluded that the described improvements to the rAd35 vector contribute significantly to the further development of rAd35 carriers for mass-vaccination programmes for diseases such as tuberculosis, AIDS and malaria.
Infectious clone construction of dengue virus type 2, strain Jamaican 1409, and characterization of a conditional E6 mutation
Authors: Pierro Dennis J. , Salazar Ma Isabel , Beaty Barry J. , Olson Ken E.
Published: July 2006

A full-length infectious cDNA clone (ic) was constructed from the genome of the dengue virus type 2 (DENV-2) Jamaica83 1409 strain, pBAC1409ic, by using a bacterial artifical chromosome plasmid system. Infectious virus was generated and characterized for growth in cell culture and for infection in Aedes aegypti mosquitoes. During construction, an isoleucine to methionine (Ile→Met) change was found at position 6 in the envelope glycoprotein sequence between low- and high-passage DENV-2 1409 strains. In vitro-transcribed genomic RNA of 1409ic with E6-Ile produced infectious virions following electroporation in mosquito cells, but not mammalian cells, while 1409ic RNA with an E6-Met mutation produced virus in both cell types. Moreover, DENV-2 1409 with the E6-Ile residue produced syncytia in C6/36 cell culture, whereas viruses with E6-Met did not. However, in vitro cell culture-derived growth-curve data and in vivo mosquito-infection rates revealed that none of the analysed DENV-2 strains differed from each other.
Intraspecific bovine herpesvirus 1 recombinants carrying glycoprotein E deletion as a vaccine marker are virulent in cattle
Authors: Muylkens Benoît , Meurens François , Schynts Frédéric , Farnir Frédéric , Pourchet Aldo , Bardiau Marjorie , Gogev Sacha , Thiry Julien , Cuisenaire Adeline , Vanderplasschen Alain , Thiry Etienne
Published: July 2006

Vaccines used in control programmes ofBovine herpesvirus 1(BoHV-1) utilize highly attenuated BoHV-1 strains marked by a deletion of the glycoprotein E (gE) gene. Since BoHV-1 recombinants are obtained at high frequency in experimentally coinfected cattle, the consequences of recombination on the virulence of gE-negative BoHV-1 were investigated. Thus, gE-negative BoHV-1 recombinants were generatedin vitrofrom several virulent BoHV-1 and one mutant BoHV-1 deleted in the gC and gE genes. Four gE-negative recombinants were tested in the natural host. All the recombinants were more virulent than the gE-negative BoHV-1 vaccine and the gC- and gE-negative parental BoHV-1. The gE-negative recombinant isolated from a BoHV-1 field strain induced the highest severe clinical score. Latency and reactivation studies showed that three of the recombinants were reexcreted. Recombination can therefore restore virulence of gE-negative BoHV-1 by introducing the gE deletion into a different virulence background.
Barley stripe mosaic virus-encoded proteins triple-gene block 2 and γb localize to chloroplasts in virus-infected monocot and dicot plants, revealing hitherto-unknown roles in virus replication
Authors: Torrance L. , Cowan G. H. , Gillespie T. , Ziegler A. , Lacomme C.
Published: July 2006

Replication ofBarley stripe mosaic virus(BSMV), genusHordeivirus, is thought to be associated with vesicles in proplastids and chloroplasts, but the molecular details of the process and identity of virus proteins involved in establishing the virus replication complexes are unknown. In addition, BSMV encodes a triple-gene block of movement proteins (TGBs) that putatively share functional roles with their counterparts in other hordei-, pomo- and pecluviruses, but detailed information on the intracellular locations of the individual TGBs is lacking. Here, the subcellular localizations of BSMV-encoded proteins TGB2 andγb fused to green or red fluorescent proteins were examined in epidermal cells ofNicotiana benthamianaand barley (Hordeum vulgare‘Black Hulless’). The fusion proteins were expressed from a BSMV vector or under the control of the cauliflower mosaic virus 35S promoter. The subcellular localizations were studied by confocal laser-scanning microscopy (CLSM). CLSM studies showed that both proteins were recruited to chloroplasts in the presence of viral RNA and that virus RNA, coat protein andγb protein were detected in plastid preparations from infected leaves. Electron microscope images of thin sections of virus-infected leaves revealed abnormal chloroplasts with cytoplasmic inclusions containing virus-like particles. In addition, cellular localizations of BSMV TGB2 suggest subtle differences in function between the hordei-like TGB2 proteins. The results indicate that TGB2 andγb proteins play a previously unknown functional role at the site of virus replication.
Replication of Bovine respiratory syncytial virus in murine cells depends on type I interferon-receptor functionality
Authors: Riffault Sabine , Dubuquoy Catherine , Castagné Nathalie , Baranowski Eric , Charley Bernard , Eléouët Jean-François
Published: July 2006

Bovine respiratory syncytial virus(BRSV) is able to counteract the alpha/beta interferon (IFN-α/β)-mediated antiviral response for efficient replication in a host-specific manner. Mice models have been developed for experimental infection with human, but not bovine, respiratory syncytial virus strains. Here, it is shown that BRSV can replicate efficiently on primary cell cultures derived from type I IFN receptor-deficient, but not from wild-type IFN-competent, mice. However, BRSV infection was not enhanced in mice devoid of the type I IFN receptor. These results show that type I IFN is a major host-range determinant for infection at the cellular level, but that other factors control virus replication and pathologyin vivo.
Effect of PVC/CPVC ratio of non‐toxic, platy pigments on corrosion protection of acrylic‐modified alkyd coatings
Authors: Emira H.S.
Published: July 2006

Purpose

This work aims to study the corrosion protection of laboratory‐prepared micaceous zinc ferrite (MZF) pigment in anticorrosive paints for steel.

Design/methodology/approach

Acrylic‐modified alkyd coatings, based on MZF pigment, micaceous iron oxide (MIO) and zinc ferrite (ZF) pigments, were prepared at different pigment volume concentrations “PVCs” to the critical pigment volume concentrations “CPVCs” ratio, which denoted hereafter by A. Scanning electron microscope, weight loss measurements, water vapour transmission (WVT) and immersion in 3.5 per cent salt solution as well as physico‐mechanical properties were performed to evaluate the paints anticorrosive performance.

Findings

WVT and corrosion protection can be affected by the PVC/CPVC ratio for all systems. At any particular PVC, the barrier property of the pigment was the main factor affecting the WVT and corrosion protection. MZF pigment protected the carbon steel physically through barrier action and chemically by the reaction with the acidic acrylic‐modified alkyd resin to produce soaps which passivate the substrate.

Originality/value

Novel MZF paint could be used with optimum percentage in anticorrosive paints for steel protection especially in humid and coastal regions.
Properties of potentiostatic passive films grown on iron electrodes immersed in weak‐alkaline phosphate solutions
Authors: Giacomelli C. , Giacomelli F.C. , Bortolluzzi R.L. , Spinelli A.
Published: July 2006

Purpose

This paper aims to study the growth and properties of potentiostatic passive films formed on iron electrodes immersed in pH 8.9‐11.0 phosphate solutions.

Design/methodology/approach

First, passive films were grown potentiostatically on pure iron electrodes under different experimental conditions (namely the Na2HPO4 concentration, time and potential of polarization, solution pH and temperature). Subsequently, the properties of the resulting passive layer were evaluated by electrochemical measurements (open circuit potential and potentiodynamic polarization measurements) and scanning electron microscopy.

Findings

The formation of passive films on iron electrodes immersed in weak‐alkaline phosphate solutions was found to occur in three main steps, being the Na2HPO4 concentration a very important parameter to promote reduction of iron dissolution. Films with protective properties could be obtained within at least 30 s of polarization at +0.50 V/SCE. The effect of the polarization potential was interpreted according to previous potentiodynamic data and the influences of solution pH and temperature follow thermodynamic laws.

Research limitations/implications

In‐situ surface analytical techniques such as extended X‐ray absorption fine structure (EXAFS) and elipsometry coupled to electrochemical measurements can elucidate more information on the film growth process, and in turn on resulting properties.

Originality/value

This contribution provides useful insights into the potentiostatic behaviour of iron in alkaline phosphate solutions.
The economics of reindeer herding
Authors: Reinert Erik S.
Published: July 2006

Purpose

This paper attempts to explain the drastic fall in income experienced by Saami reindeer herders in Northern Norway between 1976 and 2000, in spite of increasing government subsidies. Saami herders maintain a legal monopoly as suppliers of reindeer meat, a traditional luxury product in Norway.

Design/methodology/approach

This paper shows that a review of the literature is supported by qualitative interviews.

Findings

The paper argues that main explanatory variables are to be found in the interaction of a number of factors, mainly: cyclical climatic variation in Northern Norway; a system with fixed prices, independent of the variations in supply, that magnified the effects of the natural cycles; increasingly severe sanitary regulations forcing Saami herders to abandon slaughtering and preparation; and the oligopoly market powers of the non‐Saami actors taking over slaughtering and processing. It is argued that the fall in herders' income resulted from a failure of the Norwegian Department of Agriculture to understand key factors distinguishing sub‐Arctic herding from sedentary agriculture. Sanitary requirements and the government's quest for economies of scale in processing contributed to playing the volume of production into the hands of non‐Saami oligopolies. In this way the Saami herders lost the meat production that traditionally was at the core of both their culture and their economic livelihood.

Originality/value

The paper is relevant for the management of herding and other production systems in areas with cyclical production, and documents the damaging effects on the aboriginal culture resulting from Norway's exclusive use of modern agricultural science in managing such systems.
A historical study of the traditional livestock merchants of Alsace
Authors: Paul Dana Leo
Published: July 2006

Purpose

This paper is the result of empirical field research conducted in Alsace, a bi‐cultural area of France controlled by Germany from 1870 to WWI, by France between the World Wars, and by Germany during WWII. The objective of the study is to contribute to the understanding of small‐scale entrepreneurs who traditionally controlled the distribution of livestock in this bi‐cultural and multi‐lingual region.

Design/methodology/approach

This paper gives an account of the livestock distribution system, which prevailed in Alsace, until the Second World War. It uses qualitative methodology, based on oral testimonies of retired entrepreneurs and verified by means of triangulation.

Findings

The findings in this paper indicate that, in this region of traditional rivalry between French and Germans, the sector was dominated by family enterprises speaking Jédich‐Daitch, serving as a middleman minority, and dealing between French‐speakers and German‐speakers, who did not trade with one another.

Originality/value

This paper shows that, while much literature shows that middleman minorities now exist around the world, it also reveals that the concept of middleman minority existed centuries ago, in the food sector; the arrangement allowed farmers to specialise in agriculture, while specialised entrepreneurs bought and sold livestock and also provided credit to farmers. This paper is of interest to historians and anthropology/management/sociology scholars of entrepreneurship, as well as practitioners in the livestock industry.
Taking stock of open access: progress and issues
Authors: McCulloch Emma
Published: July 2006

Purpose

Aims at providing a broad overview of some of the issues emerging from the growth in open access publishing, with specific reference to the use of repositories and open access journals.

Design/methodology/approach

A paper largely based on specific experience with institutional repositories and the internationally run E‐library and information science (LIS) archive.

Findings

The open access initiative is dramatically transforming the process of scholarly communication bringing great benefits to the academic world with an, as yet, uncertain outcome for commercial publishers.

Practical implications

Outlines the benefits of the open access movement with reference to repositories and open access journals to authors and readers alike and gives some food for thought on potential barriers to the complete permeation of the open access model, such as copyright restrictions and version control issues. Some illustrative examples of country‐specific initiatives and the international E‐LIS venture are given.

Originality/value

An attempt to introduce general theories and practical implications of the open access movement to those largely unfamiliar with the movement.
Webliometrics: a new horizon in information research
Authors: Alimohammadi Dariush
Published: July 2006

Purpose

During the second half of the past century, the field of library and information science (LIS) has frequently used the research methods of the social sciences. In particular, quantitative assessment research methodologies, together with one of its associated concepts, quantitative assessment metrics, have also been used in the information field, out of which more specific bibliometric, scientometric, informetric and webometric research instruments have been developed. This brief communication tries to use the metrics system to coin a new concept in information science metrical studies, namely, webliometrics.

Design/methodology/approach

An overview of the webliography is presented, while webliometrics as a type of research method in LIS is defined. Webliometrics' functions are enumerated and webliometric research methods are sketched out.

Findings

That webliometrics is worthy of further clarification and development, both in theory and practice.

Research limitations/implications

Webliometrics potentially offer a powerful and rigorous new research tool for LIS researchers.

Practical implications

The research outputs of webliometrics, although theoretically and statistically rigorous, are of immediate practical value.

Originality/value

This paper aims to increase the knowledge of an original thought as yet under‐utilised approach to research methods.
Civil society and good governance: challenges for public libraries in South Africa
Authors: Arko‐cobbah Albert
Published: July 2006

Purpose

To demonstrate that “civil society” is an important aspect of the democratic process, providing a vital link between the citizens and the state. One of the principal functions of civil society is to maintain a watchful eye on the activities of public officials. Public libraries play an essential role in fulfilling in this regard.

Design/methodology/approach

An examination of the philosophy of civil society and governance, with accompanying analyses for the potential social applications of a variety of civic principles.

Findings

The development of an informed citizenry is one of the essential functions of public libraries and this invariably affects the participation of civil society in the affairs of state. In South Africa, for civil society to ensure good governance, there are various challenges confronting public libraries that need to be addressed. This paper enumerates those challenges and points a way forwards.

Research limitations/implications

This paper gives a variety of interpretations of the relationship between social philosophy and information science that are capable of further sophisticated theoretical elaboration.

Practical implications

The broad thrust of this paper is to emphasise the potential social benefit and significant practical outcomes of promoting library and information services within the sphere of civil society.

Originality/value

This paper gives an original insight into the relevance of public library work to the furtherance of social betterment, with particular reference to the situation in South Africa in the post‐apartheid era.
E‐learning: a philosophical enquiry
Authors: Graham Gordon
Published: July 2006

This paper focuses on successes and failures in the history of technology. It attempts to assess the wisdom of possible future courses of action with regard to technology in e‐learning and education.
Evaluation of a collaborative virtual learning environment
Authors: Akar Evren , Öztürk Ebru , Tunc¸er Bige , Wiethoff Marion
Published: July 2006

Research results concerning the evaluation of a collaborative virtual learning environment (CVLE) are presented in this paper. The focus of the evaluation is the perceptions of the learners concerning the technical and social qualities of a CVLE. It is argued in this paper that course designers and system developers should put efforts to build technically robust CVLEs with proper social infrastructure. The research results showed that although some of the failures experienced by users in CVLEs are based on technological reasons, some others are based on the lack of proper social arrangements. Additionally, if CVLEs are implemented in an international environment special attention should be paid for language and cultural differences. This research also argues about the evaluation of CVLEs that should follow a socio‐technical approach, to cover both technological and social issues.
Interactive media for learning (IML): assuring usability in terms of a learning context
Authors: Hunt Brian , Burvall Patrik , Ivergard Toni
Published: July 2006

On account of competence‐led market demands, it is important that employees gain new knowledge efficiently. One solution is to set‐up IT‐based courses using interactive media for learning (IML) so that employees can learn at their workplace and also learn as a part of their ordinary work. Choosing technology as a media for learning is not simply chosen for its own sake rather because it is more efficient for the task. However, for a number of reasons, it is becoming increasingly difficult to assess the efficient use of technology. Thus there are needs for processes to quality assure usability or even to create a process to certify usability. Before this is possible a number of issues have to be resolved. All issues are fundamental to assure usability. We address each issue in our paper. The purpose of this paper is to review current approaches to quality assurance as applied in the field of IML. This paper discusses the difficulties of distinguishing between learning and usability in an IML context. We discuss quality‐assuring usability in terms of learning and we outline a certification process for IML in terms of usability. Our concluding remarks indicate possible future research directions.
The political economy of e‐learning educational development: strategies, standardisation and scalability
Authors: Kenney Jacqueline , Hermens Antoine , Clarke Thomas
Published: July 2006

The development of e‐learning by government through policy, funding allocations, research‐based collaborative projects and alliances has increased recently in both developed and under‐developed nations. The paper notes that government, industry and corporate users are increasingly focusing on standardisation issues and the scalability of technology platforms to meet demand. This paper assesses the challenges for further development that e‐learning faces in the coming years, including: access to appropriate technology, scalability, measurement, and changed governance structures.
Employee learning in New Zealand small manufacturing firms
Authors: Coetzer Alan
Published: July 2006

Purpose

The paper aims to explain specific actions managers could take to improve support for the learning of staff and increase staff satisfaction with workplace learning.

Design/methodology/approach

The paper shows the data gathered from 464 employees in 31 small manufacturing firms through mail survey questionnaires and analysed using descriptive statistics and multiple regression.

Findings

This paper shows that the learning potential of the work systems is constrained mostly by limited employee scope for action and enhanced mainly by wide task variety. Managers are failing to create some important facilitating conditions, such as providing incentives to learn and modelling influences. Workplace supervisors are providing only low levels of learning support and are not proactive in fostering the learning of their staff. Employee perceptions of specific work environment characteristics and workplace supervisor behaviours are significant influencers of satisfaction with workplace learning.

Research limitations/implications

The paper shows future research could examine: the ability to generalise the findings by replicating the study in different contexts to rule out the manufacturing sector as an important contingency factor; and how work environment characteristics and supervisors' proximate support for learning affect other outcomes, including organisational commitment and job satisfaction.

Practical implications

This paper periodically examines characteristics of work environments and ensures that these characteristics support informal learning. Workplace supervisors need practical advice and behavioural guidelines, based on principles of adult learning, to effectively support the learning of staff. Their performance of this role should be managed.

Originality/value

The paper identifies specific managerial actions and behaviours that have potential for improving the context to support learning and increase employee satisfaction with workplace learning. It provides an employee perspective.
Employee financial participation: evidence from a major UK retailer
Authors: Morris David , Bakan Ismail , Wood Geoff
Published: July 2006

Purpose

The bulk of research on approved profit sharing and SAYE schemes tends to focus on the effects of their presence/absence, which says little about how effectively such initiatives are implemented, particularly with regard to different categories of employee. This paper seeks to contribute towards filling that gap through comparing responses between different categories of employee, and the relative effects of differing forms of financial participation.

Design/methodology/approach

The paper shows that the population for the study consisted of employees in a large (153,000 employees) retail organisation in the UK. A stratified proportionate random sampling procedure was adopted to include employees at the managerial/non‐managerial levels and in shareholder/non‐shareholder groups. A total of 1,000 questionnaires were mailed to a broad spectrum of employees and a total of 430 usable returns were received. The survey results were analysed using regression analysis.

Findings

The paper found that more junior employees are less likely to choose to actively buy into profit sharing and share ownership schemes; among workers in the lower job bands, the rewards accruing from participation in such schemes are likely to be the least, yet it is there that the effects of any undermining of collective solidarities are likely to be particularly pronounced.

Research limitations/implications

The paper shows, while based on the case of a single large enterprise, this case study highlights something of the contradictions and limitations of flexible reward systems.

Originality/value

The paper highlights the divergent effects of individualized forms of participation. On the one hand, financial participation lengthens the reward cycle; employees will be encouraged to remain with the firm, to maximise their shareholdings. On the other hand, a greater individualisation of reward systems will undermine notions of collective solidarity; workers will have different agendas according to individual choices made regarding the scale of participation in such schemes. This central contradiction will be particularly pronounced among workers in the lower job bands, where the rewards accruing from participation in such schemes is likely to be the least, yet it is there that the effects of any undermining of collective solidarities is likely to be particularly pronounced.