bluuebunny/crossref_metadata_2025 huggingface dataset:
Phenotypic, Functional, and Kinetic Parameters Associated with Apparent T-Cell Control of Human Immunodeficiency Virus Replication in Individuals with and without Antiretroviral Treatment
Authors: Emu Brinda , Sinclair Elizabeth , Favre David , Moretto Walter J. , Hsue Priscilla , Hoh Rebecca , Martin Jeffrey N. , Nixon Douglas F. , McCune Joseph M. , Deeks Steven G.
Published: October 2005

The human immunodeficiency virus (HIV)-mediated immune response may be beneficial or harmful, depending on the balance between expansion of HIV-specific T cells and the level of generalized immune activation. The current study utilizes multicolor cytokine flow cytometry to study HIV-specific T cells and T-cell activation in 179 chronically infected individuals at various stages of HIV disease, including those with low-level viremia in the absence of therapy (“controllers”), low-level drug-resistant viremia in the presence of therapy (partial controllers on antiretroviral therapy [PCAT]), and high-level viremia (“noncontrollers”). Compared to noncontrollers, controllers exhibited higher frequencies of HIV-specific interleukin-2-positive gamma interferon-positive (IL-2
+
IFN-γ
+
) CD4
+
T cells. The presence of HIV-specific CD4
+
IL-2
+
T cells was associated with low levels of proliferating T cells within the less-differentiated T-cell subpopulations (defined by CD45RA, CCR7, CD27, and CD28). Despite prior history of progressive disease, PCAT patients exhibited many immunologic characteristics seen in controllers, including high frequencies of IL-2
+
IFN-γ
+
CD4
+
T cells. Measures of immune activation were lower in all CD8
+
T-cell subsets in controllers and PCAT compared to noncontrollers. Thus, control of HIV replication is associated with high levels of HIV-specific IL-2
+
and IFN-γ
+
CD4
+
T cells and low levels of T-cell activation. This immunologic state is one where the host responds to HIV by expanding but not exhausting HIV-specific T cells while maintaining a relatively quiescent immune system. Despite a history of advanced HIV disease, a subset of individuals with multidrug-resistant HIV exhibit an immunologic profile comparable to that of controllers, suggesting that functional immunity can be reconstituted with partially suppressive highly active antiretroviral therapy.
Human Immunodeficiency Virus Type 1 Can Establish Latent Infection in Resting CD4+T Cells in the Absence of Activating Stimuli
Authors: Swiggard William J. , Baytop Clifford , Yu Jianqing J. , Dai Jihong , Li Chuanzhao , Schretzenmair Richard , Theodosopoulos Ted , O'Doherty Una
Published: October 2005

Resting CD4+T cells are the best-defined reservoir of latent human immunodeficiency virus type 1 (HIV-1) infection, but how the reservoir is formed is unclear. Understanding how the reservoir of latently infected cells forms is critical because it is a major barrier to curing HIV infection. The system described here may provide an in vitro model of latent HIV-1 infection in resting CD4+T cells. We demonstrated that HIV-1 integrates into the genomes of in vitro-inoculated resting CD4+T cells that have not received activating stimuli and have not entered cell cycle stage G1b. A percentage of the resting CD4+T cells that contain integrated DNA produce virus upon stimulation, i.e., are latently infected. Our results show that latent HIV-1 infection occurs in unstimulated resting CD4+T cells and suggest a new route for HIV-1 reservoir formation.
Protective Cytotoxic T-Cell Responses Induced by Venezuelan Equine Encephalitis Virus Replicons Expressing Ebola Virus Proteins
Authors: Olinger Gene G. , Bailey Michael A. , Dye John M. , Bakken Russell , Kuehne Ana , Kondig John , Wilson Julie , Hogan Robert J. , Hart Mary Kate
Published: October 2005

Infection with Ebola virus causes a severe disease accompanied by high mortality rates, and there are no licensed vaccines or therapies available for human use. Filovirus vaccine research efforts still need to determine the roles of humoral and cell-mediated immune responses in protection from Ebola virus infection. Previous studies indicated that exposure to Ebola virus proteins expressed from packaged Venezuelan equine encephalitis virus replicons elicited protective immunity in mice and that antibody-mediated protection could only be demonstrated after vaccination against the glycoprotein. In this study, the murine CD8
+
T-cell responses to six Ebola virus proteins were examined. CD8
+
T cells specific for Ebola virus glycoprotein, nucleoprotein, and viral proteins (VP24, VP30, VP35, and VP40) were identified by intracellular cytokine assays using splenocytes from vaccinated mice. The cells were expanded by restimulation with peptides and demonstrated cytolytic activity. Adoptive transfer of the CD8
+
cytotoxic T cells protected filovirus naïve mice from challenge with Ebola virus. These data support a role for CD8
+
cytotoxic T cells as part of a protective mechanism induced by vaccination against six Ebola virus proteins and provide additional evidence that cytotoxic T-cell responses can contribute to protection from filovirus infections.
Characterization of Parvovirus B19 Genotype 2 in KU812Ep6 Cells
Authors: Blümel Johannes , Eis-Hübinger Anna Maria , Stühler Albert , Bönsch Claudia , Gessner Matthias , Löwer Johannes
Published: October 2005

An infectious parvovirus B19 (B19V) genotype 2 variant was identified as a high-titer contaminant in a human plasma donation. Genome analysis revealed a 138-bp insertion within the p6 promoter. The inserted sequence was represented by an additional 30 bp from the end of the inverted terminal repeat adjacent to a 108-bp element found also, in inverted orientation, at the extreme right end of the unique sequence of the genome. However, despite the profound variations in the promoter region, the pattern of gene expression and DNA replication did not differ between genotype 1 and genotype 2 in permissive erythroid KU812Ep6 cells. Capsid proteins of both genotypes differ in their amino acid sequences. However, equivalent kinetics of virus inactivation at 56°C or pH 4 indicated a comparable physicochemical stability of virus capsids. Sera from six individuals infected by B19V genotype 1 were investigated on cross-neutralization of B19V genotype 2 in vitro. Similar neutralization of both B19V genotypes was observed in sera from three individuals, while the sera from three other individuals showed weaker cross-neutralization for genotype 2. In conclusion, the in vitro replication characteristics and physical stability of B19V capsids are very similar between human parvovirus B19 genotypes 1 and 2, and cross-neutralization indicates a close antigenic relation of genotypes 1 and 2.
Interaction between Brome Mosaic Virus Proteins and RNAs: Effects on RNA Replication, Protein Expression, and RNA Stability
Authors: Gopinath K. , Dragnea B. , Kao C.
Published: October 2005

Brome mosaic virus (BMV) RNA replication has been examined in a number of systems, including
Saccharomyces cerevisiae
. We developed an efficient T-DNA-based gene delivery system using
Agrobacterium tumefaciens
to transiently express BMV RNAs in
Nicotiana benthamiana
. The expressed RNAs can systemically infect plants and provide material to extract BMV replicase that can perform template-dependent RNA-dependent RNA synthesis in vitro. We also expressed the four BMV-encoded proteins from nonreplicating RNAs and analyzed their effects on BMV RNA accumulation. The capsid protein that coinfiltrated with constructs expressing RNA1 and RNA2 suppressed minus-strand levels but increased plus-strand RNA accumulation. The replication proteins 1a and 2a could function in
trans
to replicate and transcribe the BMV RNAs. None of the BMV proteins or RNA could efficiently suppress posttranscriptional silencing. However, 1a expressed in
trans
will suppress the production of a recombinant green fluorescent protein expressed from the nontranslated portions of BMV RNA1 and RNA2, suggesting that 1a may regulate translation from BMV RNAs. BMV replicase proteins 1a did not affect the accumulation of the BMV RNAs in the absence of RNA replication, unlike the situation reported for
S. cerevisiae
. This work demonstrates that the
Agrobacterium
-mediated gene delivery system can be used to study the
cis
- and
trans
-acting requirements for BMV RNA replication in plants and that significant differences can exist for BMV RNA replication in different hosts.
Mutation of a Single Conserved Nucleotide between the Cloverleaf and Internal Ribosome Entry Site Attenuates Poliovirus Neurovirulence
Authors: DeJesus Nidia , Franco David , Paul Aniko , Wimmer Eckard , Cello Jeronimo
Published: October 2005

The chemical synthesis of poliovirus (PV) cDNA combined with the cell-free synthesis of infectious particles yielded virus whose mouse neurovirulence was highly attenuated (J. Cello, A. V. Paul, and E. Wimmer, Science 297:1016-1018, 2002). Compared to the wild-type PV1 (Mahoney) [PV1(M)] sequence, the synthetic virus genome harbored 27 nucleotide (nt) changes deliberately introduced as genetic markers. Of the 27 nucleotide substitutions, the UA-to-GG exchanges at nucleotides 102/103, mapping to a region between the cloverleaf and the internal ribosome entry site (IRES) in the 5′-nontranslated region, were found to be involved in the observed attenuation phenotype in mice. The UA/GG mutation at nt 102/103 in the synthetic PV1(M) [sPV1(M)] background conferred also a ts phenotype of replication to the virus in human neuroblastoma cells. Conversely, the exchange of GG to wild-type (wt) UA at 102/103 in an sPV1(M) background restored wt neurovirulence in
CD155
transgenic (tg) mice and suppressed the ts phenotype in SK-N-MC cells. All poliovirus variants replicated well in HeLa cells at the two temperatures, regardless of the sequence at the 102/103 locus. Analyses of variants isolated from sPV(M)-infected
CD155
tg mice revealed that the G
102
G
103
-to-G
102
A
103
reversion alone reestablished the neurovirulent phenotype. This suggests that a single mutation is responsible for the observed change of the neurovirulence phenotype. sPV1(M) RNA is translated in cell extracts of SK-N-MC cells with significantly lower efficiency than PV1(M) RNA or sPV1(M) RNA with a G
102
-to-A
102
reversion. These studies suggest a function for the conserved nucleotide (A
103
) located between the cloverleaf and the IRES which is important for replication of PV in the central nervous system of
CD155
tg mice and in human cells of neuronal origin.
Effect of Alternating Passage on Adaptation of Sindbis Virus to Vertebrate and Invertebrate Cells
Authors: Greene Ivorlyne P. , Wang Eryu , Deardorff Eleanor R. , Milleron Rania , Domingo Esteban , Weaver Scott C.
Published: October 2005

Mosquito-borne alphaviruses, which replicate alternately and obligately in mosquitoes and vertebrates, appear to experience lower rates of evolution than do many RNA viruses that replicate solely in vertebrates. This genetic stability is hypothesized to result from the alternating host cycle, which constrains evolution by imposing compromise fitness solutions in each host. To test this hypothesis, Sindbis virus was passaged serially, either in one cell type to eliminate host alteration or alternately between vertebrate (BHK) and mosquito (C6/36) cells. Following 20 to 50 serial passages, mutations were identified and changes in fitness were assessed using competition assays against genetically marked, surrogate parent viruses. Specialized viruses passaged in a single cell exhibited more mutations and amino acid changes per passage than those passaged alternately. Single host-adapted viruses exhibited fitness gains in the cells in which they specialized but fitness losses in the bypassed cell type. Most but not all viruses passaged alternately experienced lesser fitness gains than specialized viruses, with fewer mutations per passage. Clonal populations derived from alternately passaged viruses also exhibited adaptation to both cell lines, indicating that polymorphic populations are not required for simultaneous fitness gains in vertebrate and mosquito cells. Nearly all passaged viruses acquired Arg or Lys substitutions in the E2 envelope glycoprotein, but enhanced binding was only detected for BHK cells. These results support the hypothesis that arbovirus evolution may be constrained by alternating host transmission cycles, but they indicate a surprising ability for simultaneous adaptation to highly divergent cell types by combinations of mutations in single genomes.
Posttranslational Modification of α-Dystroglycan, the Cellular Receptor for Arenaviruses, by the Glycosyltransferase LARGE Is Critical for Virus Binding
Authors: Kunz Stefan , Rojek Jillian M. , Kanagawa Motoi , Spiropoulou Christina F. , Barresi Rita , Campbell Kevin P. , Oldstone Michael B. A.
Published: October 2005

The receptor for lymphocytic choriomeningitis virus (LCMV), the human pathogenic Lassa fever virus (LFV), and clade C New World arenaviruses is α-dystroglycan (α-DG), a cell surface receptor for proteins of the extracellular matrix (ECM). Specific posttranslational modification of α-DG by the glycosyltransferase LARGE is critical for its function as an ECM receptor. In the present study, we show that LARGE-dependent modification is also crucial for α-DG's function as a cellular receptor for arenaviruses. Virus binding involves the mucin-type domain of α-DG and depends on modification by LARGE. A crucial role of the LARGE-dependent glycosylation of α-DG for virus binding is found for several isolates of LCMV, LFV, and the arenaviruses Mobala and Oliveros. Since the posttranslational modification by LARGE is crucial for α-DG recognition by both arenaviruses and the host-derived ligand laminin, it also influences competition between virus and laminin for α-DG. Hence, LARGE-dependent glycosylation of α-DG has important implications for the virus-host cell interaction and the pathogenesis of LFV in humans.
PrP
TSE
Distribution in a Primate Model of Variant, Sporadic, and Iatrogenic Creutzfeldt-Jakob Disease
Authors: Herzog Christian , Rivière Julie , Lescoutra-Etchegaray Nathalie , Charbonnier Aurore , Leblanc Virginie , Salès Nicole , Deslys Jean-Philippe , Lasmézas Corinne Ida
Published: October 2005

Human prion diseases, such as Creutzfeldt-Jakob disease (CJD), are neurodegenerative and fatal. Sporadic CJD (sCJD) can be transmitted between humans through medical procedures involving highly infected organs, such as the central nervous system. However, in variant CJD (vCJD), which is due to human contamination with the bovine spongiform encephalopathy (BSE) agent, lymphoreticular tissue also harbors the transmissible spongiform encephalopathy-associated prion protein (PrP
TSE
), which poses a particularly acute risk for iatrogenic transmission. Two blood transfusion-related cases are already documented. In addition, the recent observation of PrP
TSE
in spleen and muscle in sCJD raised the possibility that peripheral PrP
TSE
is not limited to vCJD cases. We aimed to clarify the peripheral pathogenesis of human TSEs by using a nonhuman primate model which mimics human diseases. A highly sensitive enzyme-linked immunosorbent assay was adapted to the detection of extraneural PrP
TSE
. We show that affected organs can be divided into two groups. The first is peripheral organs accumulating large amounts of PrP
TSE
, which represent a high risk of iatrogenic transmission. This category comprises only lymphoreticular organs in the vCJD/BSE model. The second is organs with small amounts of PrP
TSE
associated with nervous structures. These are the muscles, adrenal glands, and enteric nervous system in the sporadic, iatrogenic, and variant CJD models. In contrast to the first set of organs, this low level of tissue contamination is not strain restricted and seems to be linked to secondary centrifugal spread of the agent through nerves. It might represent a risk for iatrogenic transmission, formerly underestimated despite previous reports of low rates of transmission from peripheral organs of humans to nonhuman primates (5, 10). This study provides an additional experimental basis for the classification of human organs into different risk categories and a rational re-evaluation of current risk management measures.
Establishment and Maintenance of Kaposi's Sarcoma-Associated Herpesvirus Latency in B Cells
Authors: Chen Lei , Lagunoff Michael
Published: October 2005

Kaposi's sarcoma (KS)-associated herpesvirus (KSHV) is the infectious cause of Kaposi's sarcoma and is also associated with two B-cell lymphoproliferative diseases, primary effusion lymphoma and the plasmablastic form of multicentric Castleman's disease. KSHV is also found in the B-cell fraction of peripheral blood mononucleocytes of some KS patients. Despite in vivo infection of B cells and the ability of KSHV to infect many cell types in culture, to date B cells in culture have been resistant to KSHV infection. However, as shown here, the lack of infection is not due to the inability of B cells to support latent KSHV infection. When KSHV DNA is introduced into B cells, the virus is maintained as an episome and can establish and maintain latency over the course of months. As in all primary effusion lymphoma cell lines, there is a low level of spontaneous lytic replication in latently infected BJAB cells. Importantly, viral gene expression is similar to that of primary effusion lymphoma cell lines. Furthermore, the virus can be reactivated to higher levels with specific stimuli and transmitted to other cells, indicating that this is a productive infection. Thus B cells in culture are capable of establishing, maintaining, and reactivating from latency. These studies provide a controlled system to analyze how KSHV alters B cells during KSHV latency and reactivation.
Genomic Analysis of Anti-Hepatitis B Virus (HBV) Activity by Small Interfering RNA and Lamivudine in Stable HBV-Producing Cells
Authors: Guo Yong , Guo Hongyan , Zhang Liang , Xie Hongying , Zhao Xin , Wang Fangxun , Li Ze , Wang Yahui , Ma Shiliang , Tao Jiaping , Wang Weixing , Zhou Yuxiang , Yang Weiping , Cheng Jing
Published: October 2005

Hepatitis B virus (HBV) causes acute and chronic hepatitis and hepatocellular carcinoma. Small interfering RNA (siRNA) and lamivudine have been shown to have anti-HBV effects through different mechanisms. However, assessment of the genome-wide effects of siRNA and lamivudine on HBV-producing cell lines has not been reported, which may provide a clue to interrogate the HBV-cell interaction and to evaluate the siRNA's side effect as a potential drug. In the present study, we designed seven siRNAs based on the conserved HBV sequences and tested their effects on the expression of HBV genes following sorting of siRNA-positive cells. Among these seven siRNAs, siRNA-1 and siRNA-7 were found to effectively suppress HBV gene expression. We further addressed the global gene expression changes in stable HBV-producing cells induced by siRNA-1 and siRNA-7 by use of human genome-wide oligonucleotide microarrays. Data from the gene expression profiling indicated that siRNA-1 and siRNA-7 altered the expression of 54 and 499 genes, respectively, in HepG2.2.15 cells, which revealed that different siRNAs had various patterns of gene expression profiles and suggested a complicated influence of siRNAs on host cells. We further observed that 18 of these genes were suppressed by both siRNA-1 and siRNA-7. Interestingly, seven of these genes were originally activated by HBV, which suggested that these seven genes might be involved in the HBV-host cell interaction. Finally, we have compared the effects of siRNA and lamivudine on HBV and host cells, which revealed that siRNA is more effective at inhibiting HBV expression at the mRNA and protein level in vitro, and the gene expression profile of HepG2.2.15 cells treated by lamivudine is totally different from that seen with siRNA.
Rabies Virus P Protein Interacts with STAT1 and Inhibits Interferon Signal Transduction Pathways
Authors: Vidy Aurore , Chelbi-Alix Mounira , Blondel Danielle
Published: October 2005

Rabies virus P protein is a cofactor of RNA polymerase. We investigated other potential roles of P (CVS strain) by searching for cellular partners using two-hybrid screening. We isolated a cDNA encoding the signal transducer and activator of transcription 1 (STAT1) that is a critical component of interferon type I (IFN-α/β) and type II (IFN-γ) signaling. We confirmed this interaction by glutathione
S
-transferase-pull-down assay. Deletion mutant analysis indicated that the carboxy-terminal part of P interacted with a region containing the DNA-binding domain and the coiled-coil domain of STAT1. The expression of P protein inhibits IFN-α- and IFN-γ-induced transcriptional responses, thus impairing the IFN-induced antiviral state. Mechanistic studies indicate that P protein does not induce STAT1 degradation and does not interfere with STAT1 phosphorylation but prevents IFN-induced STAT1 nuclear accumulation. These results indicate that rabies P protein overcomes the antiviral response of the infected cells.
Actin Cytoskeleton Is Involved in Targeting of a Viral Hsp70 Homolog to the Cell Periphery
Authors: Prokhnevsky Alexey I. , Peremyslov Valera V. , Dolja Valerian V.
Published: October 2005

The cell-to-cell movement of plant viruses involves translocation of virus particles or nucleoproteins to and through the plasmodesmata (PDs). As we have shown previously, the movement of the
Beet yellows virus
requires the concerted action of five viral proteins including a homolog of cellular ∼70-kDa heat shock proteins (Hsp70h). Hsp70h is an integral component of the virus particles and is also found in PDs of the infected cells. Here we investigate subcellular distribution of Hsp70h using transient expression of Hsp70h fused to three spectrally distinct fluorescent proteins. We found that fluorophore-tagged Hsp70h forms motile granules that are associated with actin microfilaments, but not with microtubules. In addition, immobile granules were observed at the cell periphery. A pairwise appearance of these granules at the opposite sides of cell walls and their colocalization with the movement protein of
Tobacco mosaic virus
indicated an association of Hsp70h with PDs. Treatment with various cytoskeleton-specific drugs revealed that the intact actomyosin motility system is required for trafficking of Hsp70h in cytosol and its targeting to PDs. In contrast, none of the drugs interfered with the PD localization of
Tobacco mosaic virus
movement protein. Collectively, these findings suggest that Hsp70h is translocated and anchored to PDs in association with the actin cytoskeleton.
CD46 Is a Cellular Receptor for All Species B Adenoviruses except Types 3 and 7
Authors: Marttila Marko , Persson David , Gustafsson Dan , Liszewski M. Kathryn , Atkinson John P. , Wadell Göran , Arnberg Niklas
Published: October 2005

The 51 human adenovirus serotypes are divided into six species (A to F). Adenovirus serotypes from all species except species B utilize the coxsackie-adenovirus receptor for attachment to host cells in vitro. Species B adenoviruses primarily cause ocular and respiratory tract infections, but certain serotypes are also associated with renal disease. We have previously demonstrated that adenovirus type 11 (species B) uses CD46 (membrane cofactor protein) as a cellular receptor instead of the coxsackie-adenovirus receptor (A. Segerman et al., J. Virol.77:9183-9191, 2003). In the present study, we found that transfection with human CD46 cDNA rendered poorly permissive Chinese hamster ovary cells more permissive to infection by all species B adenovirus serotypes except adenovirus types 3 and 7. Moreover, rabbit antiserum against human CD46 blocked or efficiently inhibited all species B serotypes except adenovirus types 3 and 7 from infecting human A549 cells. We also sequenced the gene encoding the fiber protein of adenovirus type 50 (species B) and compared it with the corresponding amino acid sequences from selected serotypes, including all other serotypes of species B. From the results obtained, we conclude that CD46 is a major cellular receptor on A549 cells for all species B adenoviruses except types 3 and 7.
Retroviral Restriction Factor TRIM5α Is a Trimer
Authors: Mische Claudia C. , Javanbakht Hassan , Song Byeongwoon , Diaz-Griffero Felipe , Stremlau Matthew , Strack Bettina , Si Zhihai , Sodroski Joseph
Published: October 2005

The retrovirus restriction factor TRIM5α targets the viral capsid soon after entry. Here we show that the TRIM5α protein oligomerizes into trimers. The TRIM5α coiled-coil and B30.2(SPRY) domains make important contributions to the formation and/or stability of the trimers. A functionally defective TRIM5α mutant with the RING and B-box 2 domains deleted can form heterotrimers with wild-type TRIM5α, accounting for the observed dominant-negative activity of the mutant protein. Trimerization potentially allows TRIM5α to interact with threefold pseudosymmetrical structures on retroviral capsids.
Transcripts Encoding K12, v-FLIP, v-Cyclin, and the MicroRNA Cluster of Kaposi's Sarcoma-Associated Herpesvirus Originate from a Common Promoter
Authors: Pearce Michael , Matsumura Satoko , Wilson Angus C.
Published: October 2005

Kaposi's sarcoma-associated herpesvirus (KSHV) is the causative agent of three malignancies associated with AIDS and immunosuppression. Tumor cells harbor latent virus and express kaposin (open reading frame [ORF] K12), v-FLIP (ORF 71), v-Cyclin (ORF 72), and latency-associated nuclear antigen (LANA; ORF 73). ORFs 71 to 73 are transcribed as multicistronic RNAs initiating from adjacent constitutive and inducible promoters upstream of ORF 73. Here we characterize a third promoter embedded within the ORF 71-to-73 transcription unit specifying transcripts that encode ORF 71/72 or K12. These transcripts may also be the source of 11 microRNAs arranged as a cluster between K12 and ORF 71. Our studies reveal a complex arrangement of interlaced transcription units, incorporating four important protein-encoding genes required for latency and pathogenesis and the entire KSHV microRNA repertoire.
The Herpes Simplex Virus Type 1 Locus That Encodes the Latency-Associated Transcript Enhances the Frequency of Encephalitis in Male BALB/c Mice
Authors: Jones Clinton , Inman Melissa , Peng Weiping , Henderson Gail , Doster Alan , Perng Guey-Chuen , Angeletti Anisa Kaenjak
Published: October 2005

Herpes simplex virus type 1 (HSV-1) is the leading cause of virus-induced encephalitis; however, the viral genes that regulate encephalitis have not been well characterized. In this study, we tested whether the LAT (latency-associated transcript) locus regulates the frequency of encephalitis in male or female mice. Male BALB/c mice are more susceptible to HSV-1-induced encephalitis than age-matched female BALB/c mice. Deletion of LAT coding sequences reduced the frequency of encephalitis. A recombinant virus containing the first 1.5 kb of the LAT coding sequence induces levels of encephalitis in male BALB/c mice similar to those induced by wild-type HSV-1.
Sorption Profile and Thermodynamic Characteristics of Nitrosonaphthol Functionalized Sorbent for Metal Ion Enrichment
Authors: Memon Saima Q. , Bhanger Muhammad I. , Khuhawar Muhammad Y.
Published: October 2005

A simple and reliable method has been developed using styrene-divinylbenzene-based polymeric material containing 1-nitroso-2-naphthol as chelating agent, to concentrate ultratrace amounts of Ni(II) and Cu(II) ions in aqueous samples. Sorption of both the ions on the new synthetic resin under static and dynamic conditions has been investigated. The sorption has been optimized with respect to pH, shaking and contact time of two phases. Maximum sorption has been achieved from solution of pH 5-8 after 8 min of agitation. Total saturation capacities were 516 ± 2 and 316 ± 2.5 μmol g-1 for Ni(II) and Cu(II) ions, respectively. The lowest concentration for quantitative recovery (98 ± 1%) is 1.33 and 5 ppb with the preconcentration factor of 750 and 200 for Ni(II) and Cu(II), respectively. Monitoring of the influence of diverse ions on the sorption of metal ions has revealed that phosphate, hydrogencarbonate and citrate reduce the sorption to some extent. Under optimum conditions the sorption data followed Langmuir, Freundlich, and Dubinin-Radushkevich isotherms. The kinetics and thermodynamics of sorption are studied in detail. The sorption procedure is utilized to preconcentrate these ions prior to their determination in tea, human hair, and tap water samples by atomic absorption spectrometry using direct and standard addition methods.
The Antileukotrienic Derivatives and Homologues of [(Quinolin-2-ylmethoxy)sulfanyl]benzoic Acids with Reduced Lipophilicity
Authors: Kuchař Miroslav , Brunová Bohumila , Junek Richard , Rodling Robert , Hájíček Josef , Panajotová Vladimíra , Jandera Antonín
Published: October 2005

A series of ({[(quinolin-2-ylmethoxy)phenyl]sulfanyl}phenyl)acetic acids 2 and S-oxidized derivatives of {[(quinolin-2-ylmethoxy)phenyl]sulfanyl}benzoic acids 3 were prepared and their antileukotrienic and antiasthmatic activities evaluated. Regression analysis led to the conclusion that the antileukotrienic activities of compounds 2 correspond to the relationships between these activities and lipophilicity, derived for the previously synthesized series of substituted (arylsulfanyl)benzoic acids 1A, 1B and 1C. Acids 3 are outliers from these relationships, probably due to a somewhat different mechanism of action. A higher antiasthmatic activity was observed in some [(arylsulfanyl)phenyl]acetic acids 2 in comparison with the corresponding analogs bearing the (arylsulfanyl)benzoic acid moiety. The inhibition of 5-lipoxygenase activated protein (FLAP) was determined for these compounds, and the influence of the direct inhibition of LTB4 biosynthesis is discussed to explain the differences in the antiasthmatic effect of the compounds under study.
Nucleophilic Substitution and Lipophilicity - Structure Relations in Methylazolopyridazines
Authors: Katrusiak Anna , Ratajczak-Sitarz Małgorzata , Skierska Urszula , Zinczenko Wiktoria
Published: October 2005

Syntheses of methyl[1,2,4]triazolo- or methyltetrazolopyridazine isomers, their separation and nucleophilic substitution with morpholine, dimethylamine and hydrazine have been described. The lipophilicity of the azolopyridazines has been measured and related to the number and sites of the methyl substituents. The structures of new methylated azolopyridazines have been characterized by 1H NMR, MS spectra, and X-ray diffraction.
Synthesis and Biological Activity of Some 17a-Substituted Homolactones of Androst-5-ene Derivatives
Authors: Penov Gaši Katarina M. , Stojanović Srdjan Z. , Sakač Marija N. , Djurendić Evgenija A. , Csanádi János J. , Molnar-Gabor Dora , Lazar Dušan , Kovačević Radmila M.
Published: October 2005

Some new 17a-homolactones were prepared from 3β-hydroxy-16-(hydroxyimino)androst-5-en-17-one (1) as a starting compound, which was transformed first to the corresponding 17α-phenyl and 17α-benzyl derivatives 2 and 3. The structure of compound 3 was confirmed by X-ray structure analysis. Beckmann fragmentation of compounds 2 and 3 yielded 16,17-seco-cyano ketones 4-7, whose reduction with NaBH4 gave 16,17-seco-cyano alcohols 8-11, whereby the structure of compound 7 was established by X-ray structural analysis. Compounds 8-11 served as the starting compounds for obtaining lactones 12 and 13 in a reaction with potassium hydroxide in ethylene glycol. One-pot procedures were also developed for preparing 17a-homolactones 12, 13 and 16 from the hydroxyimino alcohols 2, 3 and 14. Compounds 12 and 13 showed an inhibitory activity against the enzyme aromatase (63 and 59%, respectively).
Stereoselective Preparation of Precursors of α-C-(1→3)-Disaccharides
Authors: Štěpánek Petr , Vích Ondřej , Werner Lukáš , Kniežo Ladislav , Dvořáková Hana , Vojtíšek Pavel
Published: October 2005

The stereoselectivity of cycloaddition of sugar-containing substituted 1-(thiazol-2-yl)but-2-en-1-ones1and vinyl ethers was studied using the achiral vinyl ether/chiral catalyst as well as the chiral vinyl ether/achiral catalyst combinations. It has been shown that Eu(fod)3-catalyzed cycloaddition of oxadienes1a-1ewith the chiral vinyl ethers9and10affords stereoselectively almost pure cycloadducts11a-11eand12a-12e, respectively. The obtained cycloadducts are suitable precursors for the synthesis of α-C-(1→3)-disaccharides, containing 2-deoxy-arabino-hexopyranose moiety of D- or L-configuration.
Early, active rehabilitation following mini-open repair of Achilles tendon rupture: a prospective study
Authors: Calder J D F , Saxby T S
Published: October 2005

Objective:To assess the use of a supervised active rehabilitation program following repair of acute Achilles tendon ruptures using a minimally invasive suture system.

Methods:We performed a prospective study on 46 patients undergoing surgical repair of acute Achilles tendon ruptures using the Achillon suture system. All patients began a supervised active rehabilitation program from 2 weeks postoperatively. Patients were placed in a range of motion brace fixed at 20° equinus for 2 weeks to allow wound healing followed by active movement from neutral to full plantar flexion for 4 weeks.

Results:At a minimum follow up of 12 months there were no re-ruptures. All patients were able to return to their previous sporting activities by 6 months post operation. The average American Orthopaedic Foot and Ankle Society (AOFAS) score at 6 months was 98, with 42 patients having excellent and four patients good Leppilahti scores. The average time to return to work was 22 days. One patient had a superficial wound infection which settled with 5 days of oral antibiotics. Two patients had altered sensation in the distribution of the sural nerve which settled spontaneously within 3 months.

Conclusion:The Achillon suture system appears to allow a safe early active rehabilitation program and achieves a high rate of success. Further evaluation is necessary with regard to potential damage to the sural nerve.
Superior results with eccentric compared to concentric quadriceps training in patients with jumper’s knee: a prospective randomised study
Authors: Jonsson P , Alfredson H
Published: October 2005

Background:A recent study reported promising clinical results using eccentric quadriceps training on a decline board to treat jumper’s knee (patellar tendinosis).

Methods:In this prospective study, athletes (mean age 25 years) with jumper’s knee were randomised to treatment with either painful eccentric or painful concentric quadriceps training on a decline board. Fifteen exercises were repeated three times, twice daily, 7 days/week, for 12 weeks. All patients ceased sporting activities for the first 6 weeks. Age, height, weight, and duration of symptoms were similar between groups. Visual analogue scales (VAS; patient estimation of pain during exercise) and Victorian Institute of Sport Assessment (VISA) scores, before and after treatment, and patient satisfaction, were used for evaluation.

Results:In the eccentric group, for 9/10 tendons patients were satisfied with treatment, VAS decreased from 73 to 23 (p<0.005), and VISA score increased from 41 to 83 (p<0.005). In the concentric group, for 9/9 tendons patients were not satisfied, and there were no significant differences in VAS (from 74 to 68, p<0.34) and VISA score (from 41 to 37, p<0.34). At follow up (mean 32.6 months), patients in the eccentric group were still satisfied and sports active, but all patients in the concentric group had been treated surgically or by sclerosing injections.

Conclusions:In conclusion, eccentric, but not concentric, quadriceps training on a decline board, seems to reduce pain in jumper’s knee. The study aimed to include 20 patients in each group, but was stopped at the half time control because of poor results achieved in the concentric group.
Loss ofBCL-2in the progression of oral cancer is not attributable to mutations
Authors: Loro L L , Johannessen A C , Vintermyr O K
Published: October 2005

Background:BCL-2 and BAX are important in the regulation of apoptosis. There have been reports of loss of BCL-2 in basal cells of oral epithelial dysplasia (OED) and in oral squamous cell carcinoma (OSCC), and suppression of BAX in poorly differentiated OSCC.

Aim:To investigate whether loss of BCL-2 in OED and OSCC, and of BAX in poorly differentiated OSCC could be attributed toBCL-2andBAXmutations.

Methods:Immunohistochemistry and in situ hybridisation were used to confirm BCL-2 and BAX expression. DNA was extracted from archival samples of OED (n  =  22) and OSCC (n  =  28). The connective tissue part from each section was collected separately and used as the normal reference.

Results:No mutations were detected inBCL-2orBAXthat could explain their aberrant expression at the mRNA and protein levels in OED and OSCC. The reported A/G polymorphism at codon 7 ofBCL-2was detected in 18 of 50 samples and a novel C/T polymorphism at codon 100 was detected in three of 50 samples.

Conclusions:No mutations were found that could explain loss of BCL-2 in oral dysplasia and carcinoma. An unreported C/T polymorphism inBCL-2was detected. Downregulation of BCL-2 in OED and OSCC may be the result of transcriptional regulation.
Solitary epithelial cells in B cell gastric MALT lymphoma
Authors: Sutak J , Stoddard C , Smith M E F
Published: October 2005

Background:Gastric mucosa associated lymphoid tissue (MALT) lymphoma is a low grade B cell lymphoma histologically characterised by neoplastic B cells surrounding follicles in a marginal zone pattern and selectively infiltrating epithelium to form characteristic lymphoepithelial lesions.

Aims:To identify solitary epithelial cells in gastric MALT lymphoma and investigate their nature.

Methods:Anonymised endoscopic biopsies from eight B cell gastric MALT lymphomas and 10 control biopsies from chronic atrophic gastritis were selected. The numbers of solitary cytokeratin positive epithelial cells were assessed both semiquantitatively and quantitatively in immunostained sections. Chromogranin A expression was studied in sections consecutive to those stained for cytokeratin.

Results:Statistical analysis of the quantitative data confirmed that solitary epithelial cells were significantly more common in the lymphomas. The study of consecutive sections showed that the single cells express chromogranin A.

Conclusions:The presence of solitary, cytokeratin positive epithelial cells within the neoplastic infiltrate is a characteristic feature of gastric B cell lymphoma. These solitary epithelial cells are of neuroendocrine origin.
The molecular pathogenetic role of cell adhesion in endocrine neoplasia
Authors: Ezzat S , Asa S L
Published: October 2005

It is becoming increasingly evident that cell adhesion is an important determinant of organised growth and the maintenance of architectural integrity. Indeed, reduced adhesiveness between cells and with the extracellular matrix is a hallmark of neoplastic growth. In neuroendocrine tissues, neural cell adhesion molecule is implicated in modulating cell growth, migration, and differentiation. This review will focus on the molecular pathways involving key growth factor receptors that govern normal adhesive forces. The extent to which disruption of these adhesive forces contributes to the tumorigenic process in neuroendocrine tissues will be highlighted. Validation of the functional relevance of these adhesive pathways will be discussed in light of targeted pharmacotherapeutic studies that are unmasking novel approaches to the treatment of neuroendocrine tumours.
Rare allelic imbalances, but no mutations of thePRDX1gene in human hepatocellular carcinomas
Authors: Gisin J , Perren A , Bawohl M , Jochum W
Published: October 2005

Allelic losses on chromosome 1p are frequent in hepatocellular carcinoma (HCC), suggesting the presence of a tumour suppressor gene in this region. The gene for peroxiredoxin 1 (PRDX1), an antioxidant enzyme, has been mapped to 1p34.1. Mice lacking PRDX1 develop HCC with high frequency. Because oxidative stress has been implicated in the pathogenesis of HCC, this study was designed to determine whether thePRDX1gene is mutated in human HCC using loss of heterozygosity (LOH) analysis, polymerase chain reaction/denaturing gradient gel electrophoresis, and DNA sequencing. LOH of at least one of four microsatellite markers within 0.8 Mb of thePRDX1gene was seen in three of 34 informative HCCs, but no mutations or polymorphisms in the translated exons 2–6 of thePRDX1gene were found. These results suggest that genetic alterations of thePRDX1locus are rare events in human HCC, indicating that other genes on chromosome 1p contribute to liver carcinogenesis.
PCR based identification and discrimination of agents of mucormycosis and aspergillosis in paraffin wax embedded tissue
Authors: Bialek R , Konrad F , Kern J , Aepinus C , Cecenas L , Gonzalez G M , Just-Nübling G , Willinger B , Presterl E , Lass-Flörl C , Rickerts V
Published: October 2005

Background:Invasive fungal infections are often diagnosed by histopathology without identification of the causative fungi, which show significantly different antifungal susceptibilities.

Aims:To establish and evaluate a system of two seminested polymerase chain reaction (PCR) assays to identify and discriminate between agents of aspergillosis and mucormycosis in paraffin wax embedded tissue samples.

Methods:DNA of 52 blinded samples from five different centres was extracted and used as a template in two PCR assays targeting the mitochondrial aspergillosis DNA and the 18S ribosomal DNA of zygomycetes.

Results:Specific fungal DNA was identified in 27 of 44 samples in accordance with a histopathological diagnosis of zygomycosis or aspergillosis, respectively.Aspergillus fumigatusDNA was amplified from one specimen of zygomycosis (diagnosed by histopathology). In four of 16 PCR negative samples no human DNA was amplified, possibly as a result of the destruction of DNA before paraffin wax embedding. In addition, eight samples from clinically suspected fungal infections (without histopathological proof) were examined. The two PCR assays detected a concomitant infection withAbsidia corymbiferaandA fumigatusin one, and infections withRhizopus arrhizusandA fumigatusin another two cases.

Conclusions:The two seminested PCR assays described here can support a histopathological diagnosis of mucormycosis or aspergillosis, and can identify the infective agent, thereby optimising antifungal treatment.
Prognostic value of activated Akt expression in oral squamous cell carcinoma
Authors: Lim J , Kim J-H , Paeng J-Y , Kim M-J , Hong S-D , Lee J-I , Hong S-P
Published: October 2005

Background:Akt is a serine/threonine kinase that plays an important role in tumorigenesis and influences prognosis in several cancers. However, its importance in oral squamous cell carcinomas (OSCC) has not been elucidated.

Aim:To investigate the association between the expression of activated Akt, clinicopathological factors, and E-cadherin, PCNA (proliferating cell nuclear antigen), and VEGF (vascular endothelial growth factor) expression to verify the validity of Akt as a prognostic factor in OSCC.

Methods:Phosphorylated Akt (p-Akt), E-cadherin, PCNA, and VEGF expression were assessed immunohistochemically in 84 OSCCs. The results were analysed in relation to clinicopathological factors.

Results:p-Akt was expressed in 29 cases. It was significantly correlated with lymph node metastasis, TNM stage, and E-cadherin expression. Univariate analysis showed that p-Akt expression, E-cadherin expression, PCNA expression, differentiation, tumour size, lymph node metastasis, TNM stage, and recurrence correlated with prognosis. Multivariate analysis showed that p-Akt expression is an independent prognostic factor in patients with OSCC.

Conclusions:This study revealed that Akt activation is a significant prognostic indicator for OSCC and is correlated with E-cadherin expression. The inhibition of Akt is a possible molecular approach to the treatment of OSCC.
Tumour proliferation, angiogenesis, and ploidy status in human colon cancer
Authors: Cristi E , Perrone G , Toscano G , Verzì A , Nori S , Santini D , Tonini G , Vetrani A , Fabiano A , Rabitti C
Published: October 2005

Aims:Tumour angiogenesis is essential for carcinogenesis and facilitates the process of tumour development and metastasis. Vascular endothelial growth factor (VEGF) is a well characterised angiogenetic factor and is known to play a crucial role in new vessel development. To gain further insight into the effects of microvessel density and VEGF expression in colon cancer, their relation with tumour proliferation, ploidy status, and p53 expression was investigated in colon cancer.

Methods:Tissue samples of 50 archived colon cancers were analysed by immunohistochemistry for VEGF, p53, and the endothelial cell marker, von Willebrand factor (VWF), using specific antibodies. The same samples were re-cut for flow cytometric studies to obtain S phase fraction (SPF) and ploidy status.

Results:A positive significant correlation was found between SPF and angiogenesis. The median microvessel count in high SPF tumours was significantly higher than in low SPF ones. No association was found between VEGF expression and SPF. A positive correlation was found between ploidy status and p53 expression and microvessel count. Furthermore, a positive correlation was established between DNA ploidy, VEGF expression, and microvessel count.

Conclusion:This study provides evidence that in colon cancer, tumour growth may be stimulated by vascular supply, and the lack of a correlation between tumour cell proliferation and VEGF expression indicates that these two parameters may be regulated by separate mechanisms. Furthermore, the positive correlation between microvessel density, VEGF expression, and ploidy status provides more evidence that genetic alterations are involved in tumour angiogenesis.
Immunohistochemical analysis of desmoid tumours
Authors: Leithner A , Gapp M , Radl R , Pascher A , Krippl P , Leithner K , Windhager R , Beham A
Published: October 2005

Background/Aims:Although the standard treatment for desmoid tumours is complete surgical resection with wide margins, the optimal adjuvant treatment for recurrent or inoperable disease is unclear, often being based on sporadic immunohistochemical reports with a low number of cases. Therefore, a large immunohistochemical study was performed, to provide a theoretical basis for adjuvant treatment regimens.

Methods:One hundred and sixteen tissue samples from 80 patients (49 female, 31 male; mean age, 34 years; range, 0–83) with desmoid tumours (46 extra-abdominal, 21 abdominal, 13 intra-abdominal) were tested for oestrogen receptors α and β, progesterone and androgen receptors, and somatostatin, in addition to HER2, cathepsin D, Ki-67, and c-KIT by immunohistochemistry.

Results:All samples were negative for oestrogen receptor α, HER2, and the progesterone receptor. Positive staining for the androgen receptor was found in six extra-abdominal cases. Staining for oestrogen receptor β was positive in four extra-abdominal, two abdominal, and one intra-abdominal case. Staining for somatostatin was positive in six extra-abdominal, two abdominal, and one intra-abdominal case, and staining for cathepsin D was positive in all cases. Positive staining for Ki-67 was found in 14 extra-abdominal, three abdominal, and three intra-abdominal cases. C-KIT was detectable in one abdominal case only.

Conclusions:The data from this immunohistochemical study show that the published effects of antioestrogens and imatinib mesylate in the treatment of aggressive fibromatoses may not be attributable to oestrogen receptor α or c-KIT expression.