bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetic polymorphism of CCR5 gene and HIV disease: The heterozygous (CCR5/Δccr5) genotype is neither essential nor sufficient for protection against disease progression
Authors: Morawetz Renate A. , Rizzardi G. Paolo , Glauser Didier , Rutschmann Olivier , Hirschel Bernard , Perrin Luc , Opravil Milos , Flepp Markus , von Overbeck Jan , Glauser Michel P. , Ghezzi Silvia , Vicenzi Elisa , Poli Guido , Lazzarin Adriano
Published: March 2007

Homozygous (Δccr5/Δccr5) and heterozygous (CCR5/Δccr5) deletions in the β‐chemokine receptor 5 (CCR5) gene, which encodes for the major co‐receptor for macrophage‐tropic HIV‐1 entry, have been implicated in resistance to HIV infection and in protection against disease progression, respectively. The CCR5/Δccr5 genotype was found more frequently in long‐term nonprogressors (LTNP) (31.0%) than in progressors (10.6%, p < 0.0001), in agreement with previous studies. Kaplan‐Meier survival analyses showed that a slower progression of disease, i.e. higher proportion of subjects with CD4+ T cell counts >500/μl (p = 0.0006) and a trend toward a slower progression to AIDS (p = 0.077), was associated with the CCR5/Δccr5 genotype. However, when LTNP were analyzed separetely, no significant differences in CD4+ T cell counts (p = 0.12) and viremia levels (p = 0.65) were observed between the wild‐type (69 % of LTNP) and the heterozygous (31.0 %) genotypes. Therefore, there are other factors which play a major role in determining the status of nonprogression in the majority of LTNP. Furthermore, there was no evidence that the CCR5/Δccr5 genotype was associated with different rates of disease progression in the group of progressors. Taken together, these results indicate that the CCR5/Δccr5 genotype is neither essential nor sufficient for protection against the progression of HIV disease.
Cross talk between T and B cells generates B antigen‐presenting cells able to induce inositol phosphate production in T cells responding to MIsa superantigens
Authors: O'Rourke Anne M. , Webb Susan R.
Published: March 2007

Previous studies showed that activation of CD4+ T cells with mouse mammary tumor virus‐encoded Mlsa superantigens induces strong proliferative responses and interleukin‐2 production but fails to elicit typical early T cell receptor (TCR)‐mediated signal transduction events, such as hydrolysis of polyphosphoinositides (PI) or an increase in intracellular calcium. Here we show that the failure of MIsa antigen to activate PI hydrolysis applies when resting B cells are used as antigen‐presenting cells (APC). By contrast, when MIsa‐bearing B cells are activated for 24h by exposure to lipopolysaccharide or, more importantly, to Mlsa‐reactive T cells or anti‐CD40 antibodies the cells develop the capacity to elicit easily detectable PI turnover. These studies demonstrate that, for B cells as APC, the initiation of certain TCR‐associated signal transduction pathways can depend on activation of the APC. The data suggest that cross talk between T cells and resting B cells can suffice to generate competent B APC and lead to the delayed initiation of signaling pathways important in T cell responses.
Murine model of IgE production with a predominant Th2‐response by feeding protein antigen without adjuvants
Authors: Ito Kazue , Inagaki‐Ohara Kyoko , Murosaki Shinji , Nishimura Hitoshi , Shimokata Tomoya , Torii Shinnpei , Matsuda Tukasa , Yoshikai Yasunobu
Published: March 2007

Stimulation of systemic antigen‐specific IgE production plays an important role in the mediation of food allergy; however, the mechanism of IgE production against food antigens is not fully understood. The development of relevant animal models may help to elucidate the pathogenesis of food allergy. We here show that DBA/2 mice receiving a casein diet without any adjuvant produced high levels of IgE specific for casein, accompanied by predominant Th2‐like responses in liver lymphocytes, mesenteric lymph node cells and spleen cells. This model of IgE production produced by feeding protein antigen as a constituent of the diet can be applied to investigate the mechanism of IgE production and to develop reagents for controlling food allergy.
A recombinant single chain antibody neutralizes coronavirus infectivity but only slightly delays lethal infection of mice
Authors: Lamarre Alain , Yu Mathilde W. N. , Chagnon Fanny , Talbot Pierre J.
Published: March 2007

The variable region genes of a murine anti‐coronavirus monoclonal antibody (mAb) were joined by assembly polymerase chain reaction and expressed in Escherichia coli in a single chain variable fragment (scFv) configuration. After induction of expression, the expected 32‐kDa protein was identified by Western immunoblotting with specific rabbit anti‐idiotype antibodies. The scFv fragments were purified from soluble cytoplasmic preparations by affinity chromatography on nickel agarose, which was possible with an N‐terminal but not with a C‐terminal histidine tag. Purified scFv fragments retained the antigen‐binding properties of the parental antibody, could inhibit its binding to viral antigens with apparently higher efficiency than monovalent antigen‐binding (Fab) fragments, but neutralized viral infectivity with lower efficiency (about sevenfold at a molar level). To evaluate the usefulness of these smaller and less immunogenic molecules in the treatment of viral diseases, mice were treated with purified recombinant scFv fragments and challenged with a lethal viral dose. A small delay in mortality was observed for the scFv‐treated animals. Therefore, even though the scFv could neutralize viral infectivity in vitro, the same quantity of fragments that partially protected mice in the form of Fab only slightly delayed virus‐induced lethality when injected as scFv fragments, probably because of a much faster in vivo clearance: the biologic half‐life was estimated to be about 6 min. Since a scFv derived from a highly neutralizing and protective mAb is only marginally effective in the passive protection of mice from lethal viral infection, the use of such reagents for viral immunotherapy will require strategies to overcome stability limitations.
Bacterial invasion induces interleukin‐7 receptor expression in colonic epithelial cell line, T84
Authors: Yamada Keiko , Shimaoka Motomu , Nagayama Kenichi , Hiroi Takachika , Kiyono Hiroshi , Honda Takeshi
Published: March 2007

The intestinal epithelial layer forms the interface between the external and the internal environments of a host. Since the interleukin‐7 (IL‐7) and IL‐7 receptor (IL‐7R) signaling pathway has been shown to play an important role in the mucosal immune system, we studied the expression of IL‐7R in T84, a colonic epithelial cell line, after cells were infected with several types of enteropathogenic bacteria, including Salmonella typhimurium, enteropathogenic Escherichia coli and enteroinvasive Escherichia coli. Bacterial invasion induced IL‐7R expression in T84 assessed by a semi‐quantitative reverse transcription‐polymerase chain reaction technique and flow cytometry. The inhibition of bacterial invasion by cytochalasin D, a specific inhibitor of actin polymerization, led to a reduction in the expression of IL‐7R. These data indicate that bacterial invasion into intestinal epithelial cells is likely to be an essential process in the induction of IL‐7R. The communication between the epithelium and mucosal lymphocytes which is mediated via IL‐7 and IL‐7R may be involved in the modulation of the mucosal inflammation which occurs in bacterial infection.
Induction of interleukin‐12 p40 transcript by CD40 ligation via activation of nuclear factor‐xB
Authors: Yoshimoto Takayuki , Nagase Hisashi , Ishida Takaomi , Inoue Jun‐Ichiro , Nariuchi Hideo
Published: March 2007

Interleukin‐12 is produced in response to infection with bacteria or parasites or to bacterial constituents such as LPS in monocytes/macrophages and dendritic cells, and also generated by the interaction between activated T cells and antigen‐presenting cells via CD40–CD40 ligand (CD40L). So far, transcriptional analyses of p40 have been carried out only using bacterial constituents such as LPS as stimuli. In the present study, we have characterized the transcriptional induction of p40 by CD40 ligation in a human B lymphoblastoid cell line, Daudi, and a human acute monocytic leukemia cell line, THP‐1. These cells, stimulated by an agonistic monoclonal antibody against CD40 or by transfection with a CD40L expression vector, secreted p40 and showed enhanced p40 mRNA expression. Sequence analysis of the p40 promoter region identified two potential nuclear factor (NF)‐xB binding sites conserved between mouse and human. Electrophoretic mobility shift assay revealed that the potential NF‐xB binding sequence which is located around 120 bp upstream of the transcription initiation site in murine and human p40 genes formed an NF‐xB complex with nuclear extract from Daudi cells stimulated by CD40 ligation. Moreover, transfection of Daudi cells with the polymerized NF‐xB binding sequence ligated to a thymidine kinase/chloramphenicol acetyltransferase (CAT) reporter plasmid greatly induced CAT activity, but transfection with the polymerized mutated NF‐xB binding sequence did not. These results suggest that the NF‐xB binding site located around 120 bp upstream of the transcription initiation site in murine and human p40 promoter regions could be important for the p40 induction by CD40 ligation via activation of NF‐xB.
Processing of exogenous hepatitis B surface antigen particles for Ld‐restricted epitope presentation depends on exogenous β2‐ microglobulin
Authors: Schirmbeck Reinhold , Thoma Stefan , Reimann Jörg
Published: March 2007

Processing of exogenous hepatitis B surface antigen (HBsAg) particles in an endolysosomal compartment generates peptides that bind to the major histocompatibility complex (MHC) class I molecule Ld and are presented to CD8+ cytotoxic T lymphocytes. Surface‐associated ‘empty’ MHC class I molecules associated neither with peptide, nor with β2‐microglobulin (β2m) are involved in this alternative processing pathway of exogenous antigen for MHC class I‐restricted peptide presentation. Here, we demonstrate that internalization of exogenous β2m is required for endolysosomal generation of presentation‐competent, trimeric Ld molecules in cells pulsed with exogenous HBsAg. These data point to a role of endocytosed exogenous β2m in the endolysosomal assembly of MHC class I molecules that present peptides from endosomally processed, exogenous antigen.
Prostaglandin E2 primes naive T cells for the production of anti‐inflammatory cytokines
Authors: Demeure Christian E. , Yang Liang‐Peng , Desjardins Céline , Raynauld Pierre , Delespesse Guy
Published: March 2007

In addition to their capacity to induce pain, vasodilatation and fever, prostaglandins E (PGE) exert anti‐inflammatory activities by inhibiting the release of pro‐inflammatory cytokines by macrophages and T cells, and by increasing interleukin (IL)‐10 production by macrophages. We here report that PGE2, the major arachidonic acid metabolite released by antigen‐presenting cells (APC), primes naive human T cells for enhanced production of anti‐inflammatory cytokines and inhibition of pro‐inflammatory cytokines. Unfractionated as well as CD45RO−CD31+ sort‐purified neonatal CD4 T cells acquire the capacity to produce a large spectrum of cytokines after priming with anti‐CD3 and anti‐CD28 monoclonal antibodies (mAb), in the absence of both APC and exogenous cytokines. PGE2 primes naive T cells in a dose‐dependent fashion for production of high levels of IL‐4, IL‐10 and IL‐13, and very low levels of IL‐2, interferon (IFN)‐γ, tumor necrosis factor (TNF)‐α, and TNF‐β. PGE2 does not significantly increase IL‐4 production in priming cultures, whereas it suppresses IL‐2 and IFN‐γ. Addition of a neutralizing mAb to IL‐4 receptor in primary cultures, supplemented or not with PGE2, prevents the development of IL‐4‐producing cells but does not abolish the effects of PGE2 on IL‐10 and IL‐13 as well as T helper (Th)1‐associated cytokines. Addition of exogenous IL‐2 in primary cultures does not alter the effects of PGE2 on naive T cell maturation. Thus PGE2 does not act by increasing IL‐4 production in priming cultures, and its effects are partly IL‐4 independent and largely IL‐2 independent. Together with the recent demonstration that PGE2 suppresses IL‐12 production, our results strongly suggest that this endogenously produced molecule may play a significant role in Th subset development and that its stable analogs may be considered for the treatment of Th1‐mediated inflammatory diseases.
Study of the Defects in Sintered SnO2 by High‐Resolution Transmission Electron Microscopy and Cathodoluminescence
Authors: Maestre David , Ramírez‐Castellanos Julio , Hidalgo Pedro , Cremades Ana , González‐Calbet José M. , Piqueras Javier
Published: March 2007

The defect structure of sintered SnO2 was investigated by high‐resolution transmission electron microscopy (HRTEM), cathodoluminescence (CL), and electrical measurements. HRTEM shows the presence of the SnO phase in the sintered samples as well as twinning, stacking faults, and disordered intergrowths. The sintered samples annealed under an oxygen atmosphere show changes in the defect structure and in the CL spectra. In particular, the intensity of a CL band at 1.94 eV, related to oxygen vacancies, decreased as the electrical resistivity increased. The results are discussed by considering the presence of stoichiometric defects such as oxygen vacancies and Sn interstitials in the final structure and their evolution during the annealing process under an oxygen atmosphere. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Spin‐Crossover Studies on a Series of 1D Chain and Dinuclear Iron(II) Triazine‐Dipyridylamine Compounds (Eur. J. Inorg. Chem. 8/2007)
Authors: Neville Suzanne M. , Leita Ben A. , Offermann Daniel A. , Duriska Martin B. , Moubaraki Boujemaa , Chapman Karena W. , Halder Gregory J. , Murray Keith S.
Published: March 2007

The cover picture shows the one‐dimensional polymeric iron(II) spin crossover material, Fe(NCX)2(cddt)·n(guest) (X = S or Se) containing the ligand 2‐chloro‐4,6‐bis(dipyrid‐2‐ylamino)‐1,3,5‐triazine. The thiocyanate analogue undergoes a “half” spin crossover, illustrated at the bottom, where at low temperatures there are alternating, crystallographically distinct, high spin (yellow) and low spin (red) iron(II) centres (as can be seen in the structural diagram). The selenocyanate material undergoes a full spin crossover illustrated at the base of the image. Further characterisation of the thiocyanate material has been carried out by powder X‐ray diffraction using synchrotron radiation; a representative image is shown in the background of the picture. Details are discussed in the article by K. S. Murray et al. on p. 1073 ff.
Biofilm growth kinetics on hydrocarbon in a porous medium under biostimulation conditions
Authors: Joannis‐Cassan C. , Delia M.‐L. , Riba J.‐P.
Published: March 2007

The formation of biofilm on hydrocarbon in a porous medium under biostimulation conditions was investigated in order to a better understanding of microbial development during bioremediation of hydrocarbon‐contaminated soils. Pseudomonas alkanolytica ATCC 21034 was studied as it grows embedded in a biofilm on dodecane surface. First, an experimental protocol for determination of biofilm growth kinetics on hydrocarbon in a porous medium was proposed. Six identical columns packed with sand were run simultaneously. The growth kinetics was obtained by measuring the biofilm dry weight of each column at different times. The reproducibility of the experimental protocol was validated using statistical tests. Then biofilm growth kinetics was established in the porous medium for two specific surfaces of dodecane (large or small droplets). A linear growth was observed due to transport limitation of both dodecane and dissolved oxygen in the biofilm. So the degradation of dodecane was uncompleted. Moreover, difficulty to bring dissolved oxygen in the deeper part of the porous medium was pointed out. All these phenomena could explain some failures encountered during biostimulation processes. © 2007 American Institute of Chemical Engineers Environ Prog, 2007
Synthesis, structures, and luminescence properties of ternary supramolecular hydrogen‐bonded complexes involving [(o‐C6F4)Hg]3, carbazole, and a Lewis base
Authors: Burress Charlotte N. , Gabbaï François P.
Published: March 2007

The interaction of trimeric perfluoro‐ortho‐phenylene mercury (1) with carbazole in dichloromethane, THF, and THF/NEt3 leads to the crystallization of [1·C12H8NH] (2), [1·(C12H8NH·THF)] (3), and [1·(C12H8NH·NEt3)] (4), respectively. Adducts 3 and 4 have been characterized by elemental analysis, IR spectroscopy, and luminescence spectroscopy. The crystal structures of 3 and 4 have also been determined. Both adducts have extended structures that exhibit supramolecular binary stacks, where molecules of 1 and the carbazole–Lewis base complex alternate. Short Hg–C contacts involving molecules of 1 and carbazole indicate the presence of secondary Hg–π interactions. In addition, adducts 3 and 4 display hydrogen‐bonding interactions between the acidic NH moiety of carbazole and the heteroatom of the Lewis base. The presence of this hydrogen bond is also confirmed by IR spectroscopy, which shows that the νNH of 3 and 4 is lower than that of 2. The luminescence spectra of these adducts correspond to the phosphorescence of carbazole, which is induced by the mercury heavy atom effect. In the case of 3 and 4, additional low‐energy bands are observed at 578 and 567 nm. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:195–201, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20329
Extracellular adenosine triphosphate induces glutamate transporter‐1 expression in hippocampus
Authors: Frizzo Marcos E. , Frizzo Juliana K. , Amadio Susanna , Rodrigues Juliana M. , Perry Marcos L. , Bernardi Giorgio , Volonté Cinzia
Published: March 2007

ATP can be significantly released following various brain insults and activates the extracellular signal‐regulated protein kinase (ERK) pathway in astrocytes. Glutamate transporter‐1 (GLT1) is the major forebrain astroglial glutamate transporter and its expression is stimulated also via ERK1/2 phosphorylation. We thus hypothesized that extracellular ATP could be a signal to GLT1 modulation in hippocampal slices obtained from rat. We indeed observed by western blot analysis that, after 1 mM ATP exposure, GLT1 expression, but not the glutamate–aspartate transporter, was enhanced. At the same time, high ATP induced significant rates of cell death in piramidal and granule cell layers, as shown by propidium iodide uptake, and increased glutamate uptake through GLT1 transporter. Also using confocal laser‐scanning microscopy, we observed that ATP induced a vigorous and extensive GLT1‐labeling on glial fibrillary acidic protein‐positive cells. This stimulation was abolished by purine/pyrimidine nucleotide receptor antagonists and by MEK1/2 inhibitor. The present study demonstrates a novel mechanism of GLT1 regulation by extracellular ATP, reinforcing the evidence of cross talk between glutamatergic and purinergic systems. © 2007 Wiley‐Liss, Inc.
A quantum chemistry study: A new kind of boron nitrides
Authors: Li Qian Shu , Xu Yu
Published: March 2007

At the B3LYP/6‐311+G** and the BP86/6‐311+G** levels of theory, BNN, H3BNN, NNBH2‐BH2NN, (BNN)2H2, NNBBNN, (BNN), (BNN)4, (BNN), (BNN), B4(NN)2, (BNN), (BNN)6, (BNN), and (BNN) are investigated. Neutral (BNN)4 is aromatic with its triplet state but antiaromatic with its singlet state. (BNN)4 dication favors D2d structure, while (BNN)4 dianion favors a planar D4h structure. (BNN), (BNN), (BNN), (BNN)6, (BNN), (BNN), (BNN), and (BNN) are all aromatic with planar monocyclic conformation, following the 4n + 2 rule. Moreover, according to the CASSCF and MRCI calculations, the planar B4(NN)2 of D2h symmetry prefers to be a σ‐π diradical in spite of open‐shell singlet or triplet and is also aromatic. Akin to the σ‐π back interaction in compounds containing transition metal, there exists the σ‐π back interaction between boron and N2 ligand among some species reported herein, which strengthens B−N bond but activates NN bond, especially in 4Σ− BNN. The T‐shaped structure lies lowest in energy among seven isomers of the (BNN)2H2 dimer, and the parallel‐displaced structure is favored between two isomers of the (BNN)6 dimer. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2007
Generation and characterization of tTS‐H4: a novel transcriptional repressor that is compatible with the reverse tetracycline‐controlled TET‐ON system
Authors: Bockamp Ernesto , Christel Cerstin , Hameyer Dorothe , Khobta Andriy , Maringer Marko , Reis Marco , Heck Rosario , Cabezas‐Wallscheid Nina , Epe Bernd , Oesch‐Bartlomowicz Barbara , Kaina Bernd , Schmitt Steffen , Eshkind Leonid
Published: March 2007

Background

Conditional gene regulatory systems ensuring tight and adjustable expression of therapeutic genes are central for developing future gene therapy strategies. Among various regulatory systems, tetracycline‐controlled gene expression has emerged as a safe and reliable option. Moreover, the tightness of tetracycline‐regulated gene switches can be substantially improved by complementing transcriptional activators with antagonizing repressors.

Methods

To develop novel tetracycline‐responsive transcriptional repressors, we fused various transcriptional silencing domains to the TetR (B/E) DNA‐binding and dimerization domain of the Tn10‐encoded tetracycline resistance operon (TetR (B/E)). The resulting fusion proteins were individually tested for their ability to repress transcription of the constitutively active hypoxanthine phosphoribosyltransferase (HPRT) promoter. In addition, compatibility with the commonly used reverse tetracycline‐controlled transactivator system (rtTA‐system) and responsiveness to the pharmacological effector doxycycline (DOX) were evaluated. Finally, inducibility, effector‐dependent promoter activity and the modification of histone H3 and H4 of the active versus the repressed target promoter were determined.

Results

Fusion of the human deacetylase 4 (HDAC4) carboxy‐terminal silencing domain to TetR (B/E) resulted in a functional transcriptional repressor. This novel repressor, termed tTS‐H4, efficiently reduced the activity of the murine HPRT promoter and a constitutively active human cytomegalovirus (hCMV) minimal promoter. Furthermore, combining tTS‐H4 with the rtTA transcriptional activator allowed for grading, turning off and resuming target gene expression over several orders of magnitude without background.

Conclusions

The tTS‐H4 repressor is compatible with the commonly used rtTA transcriptional activation system and is a versatile new tool for tightly and adjustably regulating conditional gene expression. Copyright © 2007 John Wiley & Sons, Ltd.
Studies of an outbreak of acute hepatitis A: I. Complement level fluctuation
Authors: Baer G. M. , Walker J. A. , Yager P. A.
Published: March 2007

An outbreak of hepatitis A occurred in a rural elementary school in Colbert County, Alabama, in October and November 1972. The outbreak was caused by sewage‐contaminated drinking water and involved 49 children and 1 adult. Acute and convalescent serum samples were obtained from the hepatitis patients, and from each of 24 unafflicted matched controls at the same time. Strikingly, the levels of the third and fourth components of complement (C'3 and C'4) were markedly reduced in the acute samples from the sick children but returned to normal in the convalescent ones; the C'3 and C'4 levels in the healthy matched controls were not reduced. In addition, antigen‐antibody complexes were found in convalescent sera from some of the sick children. These findings indicate that immune complexes are present in acute hepatitis A and suggest that the techniques for future virus isolation may have to be altered.
Studies of an outbreak of acute hepatitis A: II. Antibody changes to cytomegalovirus and herpesvirus
Authors: Baer G. M. , Yager P. A. , Hierholzer J. C. , Walker J. A. , Almeida J. D.
Published: March 2007

The acute and convalescent sera from 14 schoolchildren with acute hepatitis A were tested for antibody changes to 70 viral antigens. Marked decreases were noted in the levels of antibody to cytomegalovirus in 5 of the 14 children and in the levels of antibody to herpesvirus type 1 in 3. No such changes were noted in 9 sex‐ and age‐matched healthy control children from the same classes.
The effect of intradermal administration of corynebacterium parvum on the immune response to hepatitis Bs antigen
Authors: Papaevangelou G. , Sparros L. , Vissouls Ch. , Kyriakidou A. , Giokas G. , Hadzimanolis J. , Trichopoulos D.
Published: March 2007

The immunopotentiating effect of the intradermal administration of a course of four doses (0.25 ml) of a standard suspension of killed C. parvum (2 mg/ml) was studied in a group of 10 asymptomatic chronic hepatitis B surface antigen (HBsAg) carriers, as well as in 11 persons with antibodies to HBsAg (anti‐HBs) and six without HBsAg or anti‐HBs. HBsAg, anti‐HBs, and leukocyte migration inhibition (LMI) studies were performed in pre‐ and post‐inoculation blood samples. C. parvum produced a substantial increase of anti‐HBs titre in persons with preexisting anti‐HBs. However, anti‐HBs responses were not induced in carriers. HBsAg was not eliminated and its titre remained practically unchanged in carriers. These results support the hypothesis that in carriers the specific defect in the immune response to HBsAg possibly exists at the B cell level.
The virion and soluble antigen proteins of variola, monkeypox, and vaccinia viruses
Authors: Esposito Joseph J. , Obijeski John F. , Nakano James H.
Published: March 2007

The structural proteins in purified preparations of variola, monkeypox, and vaccinia viruses were separated and compared by using a high resolution SDS‐polyacrylamide gel electrophoresis system. About 30 proteins were resolved for each virus by autoradiography of longitudinally‐sliced gel rods. Although the autoradioelectropherograms of each virus were similar, it was possible to differentiate them by their unique protein pattern in the 30,000 to 40,000 molecular weight region of the gels. A single virion glycoprotein (mol. wt. = 38 × 103) and a virion phosphoprotein (mol. wt. = 12 × 103) were associated with each of the virus preparations.

Cross‐absorbed monospecific immune sera against variola, monkeypox, and vaccinia virus‐infected cells were used in immunodiffusion tests to precipitate radiolabeled, homologous, soluble antigen proteins. The predominant antigen protein associated with each immunospecific precipitate had a molecular weight of approximately 73,000.
Biological and biochemical characterization of a latent subacute sclerosing panencephalitis (SSPE) virus infection in tissue culture
Authors: Kratzsch Volker , Hall William W. , Nagashima Kazuo , ter Meulen Volker
Published: March 2007

The present investigation describes the biological and biochemical properties of a persistent SSPE virus infection. Persistently infected cells were derived by cocultivation of infected brain cells and uninfected Vero cells, and cultures were maintained by normal subculturing methods.

No infectious virus was ever released from these cultures, and all attempts to induce infectious virus release were unsuccessful. Biological assays showed that infected cells contained nucleocapsid and salt‐dependent hemagglutinin antigens, whereas the normal hemagglutinin appeared not to be present. Electron microscopic examination demonstrated the presence of both intranuclear and cytoplasmic nucleocapsids together with the release of virus particles (defective?) from the cell membrane.

Biochemical analysis demonstrated that approximately 90% of the intracellular genomic RNA was defective or subgenomic although a small quantity of infectious genomes was present.

It is proposed that the large quantities of defective genomes in the infected cells are the major factor in the maintenance of this persistent infection.
Seroepidemiological investigation of patients and family contacts in an epidemic of hepatitis A
Authors: Frösner Gert G. , Overby Lacy R. , Flehmig Bertram , Gerth Hans‐Joachim , Haas Hans , Decker Richard H. , Ling Chung‐Mei , Zuckerman Arie J. , Frösner Helga‐Ruth
Published: March 2007

Serial blood and faecal samples were collected from patients and family contacts during an outbreak of hepatitis A in a village and tested by a solid‐phase competitive type radioimmunoassay for hepatitis A antigen and hepatitis A antibody. The amount and duration of excretion of hepatitis A antigen was correlated with the severity of the illness. In 2 severe clinical cases, hepatitis A antigen was demonstrated in faecal extracts 11 days before the onset of jaundice and continuing for 10 days thereafter, with maximum shedding during the late incubation period. Faecal antigen was demonstrated in low concentrations for only 2 days in a patient with mild disease and in a person with subclinical infection. There was an inverse correlation between the incidence of infection and prevalence of hepatitis A antibody and age. Of 24 infections, 19 (79%) occurred in persons in the age group 0 to 20 years, a group in which only 6% of individuals had pre‐existing antibody. Hepatitis A antibody was present in the serum of 3 persons in low titres of 1:20 to 1:40 on the day jaundice developed. The antibody titres increased very rapidly during the following 2 weeks of illness and slowly during the following months, reaching titres of 1:900 to 1:3500. In a separate study, a mean antibody titre of 1:591 was found in 13 patients, 12 years after clinical hepatitis A with jaundice.
Acute optic neuritis: A virological study in relation to multiple sclerosis
Authors: Santoli Daniela , Wroblewska Zofia , Cremer Natalie E. , Lief Florence S. , Schatz Norman
Published: March 2007

Previous ultrastructural examination of peripheral blood lymphocytes revealed the presence of intranuclear filamentous structures in multiple sclerosis (MS) and in some optic neuritis (ON) patients. The present investigation was undertaken in the attempt to correlate the presence of such structures with the etiology of ON and MS and possibly to demonstrate the viral origin of the filaments. Suitable virological and serological techniques were used to detect and isolate infectious agents from peripheral blood samples and body excretions of 12 monosymptomatic ON patients at their first acute attack. Nevertheless, any efforts to demonstrate the presence of a virus in these patients have been unsuccessful: no evidence of active viral infection was obtained by serological studies of serum and cerebrospinal fluid samples, nor could viral antigens or inclusions be observed by immunofluorescence and cytochemical analysis. Negative results were also obtained from studies performed in parallel on MS patients and various controls. The significance of the failure to isolate infectious agents from either ON and MS patients is discussed.
Immunotherapy of viral infections with transfer factor
Authors: Mazaheri M. R. , Hamblin Anne S. , Zuckerman A. J.
Published: March 2007

It has been reported that dialysable leucocyte extract preparations, thought to contain transfer factor, may be used therapeutically for the treatment of a variety of immunodeficiency syndromes. Clinical and laboratory studies have suggested that such preparations, in addition to transferring specific cellular immunity may also contain non‐specific adjuvant activities. Attempts at immunotherapy of viral infections are described against a background of current research on the biological and biochemical properties of leucocyte dialysates.
Picorna‐ and togavirus infection of cells detected by gas chromatography
Authors: Levanon A. , Klibansky Y. , Kohn A.
Published: March 2007

Viral infection of cells causes chemical and metabolic changes, which can be detected by gas chromatography (GC) of ether extracts of supernatant fluids and cell homogenates. before any significant damage to the cells is observable microscopically. The characteristic and specific GC patterns obtained from BHK‐21 and Vero cell cultures infected with encephalomyocarditis, polio, echoviruses, and a togavirus make it possible to distinguish between these infecting viruses. The appearance of 1 or 2 compounds, represented by GC peaks with TR values of 302 and 677 seconds seems to be specific for these viruses. Other peaks found in the supernatant media 1–2 hours after infection probably represent cell constituents leaking into the medium as a result of damage to the cell membrane by the invading virus.
Tampon culture for quantitation of cervicovaginal herpes simplex virus
Authors: Ekwo Edem E. , Myers Martin G.
Published: March 2007

From 101 to 106 TCID50 (mean tissue culture infective doses) per ml HSV I and II can be quantitatively recorded from vaginal tampons. Tampons and sterile cotton swabs are equally sensitive in recovering HSV I and II. Direct cotton swab cultures of the cervix and cervicovaginal tampon cultures from the same patients recovered similar quantities of HSV, ranging from 1.5 to 6.5 log10 TCID50 /ml in 5 patients.
Pattern of shedding of two noncultivable viruses in stools of newborn babies
Authors: Cameron D. J. S. , Bishop R. F. , Veenstra A. A. , Barnes G. L. , Holmes I. H. , Ruck B. J.
Published: March 2007

Noncultivable viruses have been associated with diarrhea affecting newborn babies in obstetric hospital nurseries. Persisting infection in a special care nursery in Melbourne, Australia, permitted a study of the pattern of excretion of these viruses. Ten babies admitted to the nursery within 2 hr of birth were randomly selected for prospective study. Feces were collected daily for 14 days and were examined by electron microscopy. All ten babies excreted detectable amounts of duovirus (rotavirus, HRVL agent, IGV) for at least 1 day. Age at onset of excretion varied from 2 to 13 days. Eight of the ten babies developed diarrhea. Excretion of duovirus preceded the onset of diarrhea by 12–72 hr and persisted for at least 3 days.

Seven of the ten babies also excreted detectable amounts of a 28‐nm virus‐like particle for 3–8 days. The identity of this particle is unknown. Morphologically it resembles Norwalk agent and “astrovirus.” Excretion of this 28‐nm particle coincided with symptoms of diarrhea in four babies, all of whom were also excreting duovirus.

It is concluded that most newborn babies admitted to a nursery where duovirus infection is endemic will excrete this virus at least once during the first 2 weeks of life. Excretion of virus particles will either precede development of diarrhea or be asymptomatic. Selective isolation of babies with diarrhea is thus unlikely to control spread of duovirus infection within a hospital nursery.
Cytomegalovirus proteins: II. Polypeptide composition of cytomegalovirus complement‐fixing antigen
Authors: Fiala Milan , Heiner Douglas C. , Murnane John , Guze Lucien B.
Published: March 2007

Complement‐fixing (CF) antigen, prepared from cytomegalovirus (CMV)‐ infected cells and solubilized by urea and Tween‐20, was fractionated on agarose gel columns. Its molecular weight was 1.5−5 × 107 daltons, and it contained 5 major peptides with molecular weights from 60,000–90,000 daltons. The peptide with a molecular weight of 70,000 daltons which was present in the solubilized CF antigen was absent in a soluble fraction from infected cells without CF activity and may be, therefore, important in this respect. The antigens present in the CF antigen did not elicit neutralizing antibody.
Pathogenesis of a Venezuelan encephalitis virus strain lethal for adult white rats
Authors: Jahrling Peter B. , DePaoli Alexander , Powanda Michael C.
Published: March 2007

The pathogenesis for adult rats of a Venezuelan encephalitis virus (VEE) strain, V‐198, was studied. This virus strain was chosen following virulence‐testing of 12 prototype alphavirus strains, selected from the Semliki Forest, Venezuelan, Eastern, and Western encephalitis virus complexes; only VEE strain V‐198 killed all adult rats when inoculated subcutaneously (sc) with 6.0–6.5 log10 plaque‐forming units (PFU). Lower doses of strain V‐198 by the same route were also lethal: 5.0 and 3.0 log10 PFU killed 100%, and 1.0 log10 PFU killed 70% of rats. Viral infectivity titrations of tissues obtained from V‐198 straininfected rats demonstrated that virus replicated early in thymus and spleen, but did not replicate in bone marrow or liver. Following a brief viremia, virus infectivity titers peaked in brain, but did not persist there. A biphasic neutrophilia also occurred. Lower doses of inoculum virus affected the timing but not the degree of neutrophil fluctuations, virus replication, and clinical disease. Rats, moribund seven days after inoculation of 4.3 log10 PFU, exhibited central nervous system signs and histologic evidence of encephalomyelitis. Significant proportions of rats, otherwise lethally infected with V‐198 virus, were protected by a single intraperitoneal inoculation of hyperimmune V‐198 antiserum, administered 3 or 4, but not 5 days after virus.

Since the rat has been well characterized with respect to metabolic alterations following other infectious diseases, it is anticipated that this model for lethal virus‐induced disease will be useful for defining more precisely the functional relationships between viral growth, tissue destruction, metabolic alterations, and clinical course of disease, and that it may suggest specific approaches for effective treatment of viral diseases in general.
Enhanced parainfluenza I (6/94) virus detection in latently infected human brain cell cultures by treatment with cytochalasin D and dimethyl sulfoxide
Authors: Wroblewska Zofia , Wellish Mary , Gilden Donald H.
Published: March 2007

The ability of cytochalasin D (CD) and dimethyl sulfoxide (DMSO) to enhance parainfluenza I (6/94) virus replication was studied in various cell culture systems. Treatment of CV1 cells with CD (1 μg/ml) dissolved in DMSO prior to primary 6/94 virus exposure at 100–105 multiplicities of infection did not substantially enhance virus replication. However, there was a transient increase in cell associated virus one day after infection of DMSO‐treated cultures. CD treatment of cultures of human brain cells latently infected with 6/94 virus (LIHB cells) did not enhance 6/94 virus detection. Cocultivation of CV1 cells with CD‐treated LIHB cell cultures, and cocultivation of LIHB cell cultures with CD‐treated CV1 cells, resulted in the production of both cell‐associated and cell‐free 6/94 virus three and five days after cocultivation. No virus was detected after similar cocultivation of untreated LIHB cell cultures with untreated CV1 cells. The usefulness of CD‐DMSO treatment in the rescue of virus from 6/94 LIHB cell cultures appears limited to a cocultivation system. The use of these techniques to enhance virus rescue from human tissues suspected of harboring latent viral genomes is discussed.
Relationship of human adenoviruses 12, 18, and 31 as determined by hemagglutination inhibition
Authors: Wigand R. , Keller Doris
Published: March 2007

Adenoviruses 12 and 31, but not Ad 18, agglutinate rat blood cells at high titer, providing suitable blood cells be available and a prolonged contact period of virus with the erythrocytes is allowed. Purified virus particles show direct, and virus‐free supernatants show direct and indirect, hemagglutination, ie, enhancement of HA by heterologous antiserum. Hemagglutination inhibition with rabbit antisera shows cross‐reactions between Ad12 and Ad31 with liters 4–32 times lower than with homologous antigens; Ad18 antisera react with antigens from both of the other serotypes. No cross‐reactions were seen with antisera from other adenoviruses. This suggests an antigenic relationship of the three viruses of subgroup IV in their fiber antigen γ, in addition to the known relation in the hexon (ϵ), which is apparent in cross‐neutralization.
Glycoproteins of representative paramyxoviruses: Isolation and antigenic analysis using a zwitterionic surfactant
Authors: Dyke Saleh F. , Williams Wanda , Seto J. T.
Published: March 2007

A new method for the isolation of biologically active envelope antigens from paramyxo‐ and myxoviruses was developed using a zwitterionic detergent Empigen BB. Essentially complete recovery of hemagglutinin and sialidase from representative paramyxoviruses (PMY, NDV, and Sendai virus) and influenza virus X7 was achieved. The glycoproteins (HN and F) of PMY were purified in a DEAE‐Bio‐Gel A column equilibrated with bicarbonate buffer containing Empigen, Polyacrylamide gel electrophoresis analysis of pooled HN fractions revealed one band, indicating that it is a common glycoprotein. Gels of pooled F‐enriched fractions revealed three bands corresponding to LGP, HN, and F. Gels of PMY virus revealed six polypeptides, and they have been tentatively designated L, LGP, HN, F, NP, and M. LGP, a large glycoprotein, was not detected in gels of NDV and Sendai virus. It has been proposed that LGP may consist of a complex of F. Antiserum was prepared against purified HN and it was found to be monospecific. The antiserum inhibited both hemagglutination and enzyme activities of PMY, which is in support of the hemagglutinin and sialidase of PMY being associated with a common glycoprotein. By enzyme inhibition analysis of PMY, NDV, and Sendai virus, it was shown that the enzymes of these viruses are antigenically distinct. The methods described for the isolation and purification of PMY glycoproteins may be useful for the preparation of myxo‐ and paramyxovirus subunit vaccines.
The coating of respiratory syncytial (RS) virus‐infected cells in the respiratory tract by immunoglobulins
Authors: Gardner P. S. , McQuillin J.
Published: March 2007

During the course of 26 respiratory syncytial (RS) virus infections, infected cells in the respiratory tract become coated with immunoglobulins (IgA, IgG, and IgM), IgA being predominant. Methods are described for detecting both intracellular virus and coating immunoglobulin using a double staining technique and immunofluorescence.

IgA coating antibody appears in small amounts very early in the illness. The relationship of coating antibody to pathogenesis, prevention, and recovery from RS virus infection is discussed.
Antigenic sites related to human serum proteins in HBsAg: Isolation from normal human serum of a high‐molecular‐weight glycoprotein reacting with antialbumin
Authors: Neurath A. R. , Strick N. , Huang C. Y. , Prince A. M.
Published: March 2007

A novel minor constituent was isolated from normal human serum by affinity chromatography on columns of insolubilized concanavalin A and antibodies to albumin, followed by rate zonal centrifugation. This component has the following properties: a sedimentation coefficient of approximately 31; a diameter of 14–22 nm, and a buoyant density of 1.302 gm/cu cm. It contains about 1% neutral sugars and is electrophoretically heterogeneous, since two populations of particles with isoelectric points of pH 4.95 and 5.75 were separated by isoelectric focusing. It contains a single major glycopeptide with an apparent molecular weight of 72,000 daltons. Its amino acid composition is distinct from that of albumin. It elicited the formation of antibodies that also reacted with HBsAg.
Effect of ethanol during hepatitis B virus infection in chimpanzees
Authors: Tabor Edward , Gerety Robert J. , Barker Lewellys F. , Howard Colin R. , Zuckerman Arie J.
Published: March 2007

To determine whether the use of ethyl alcohol (ethanol, C2H5 OH) may increase the liver damage caused by hepatitis B virus infection, ethanol was infused into four chimpanzees on one or two occasions during the course of natural or experimentally induced hepatitis B virus infections. A fifth chimpanzee, without active hepatitis B virus infection, served as a control. Moderate elevations of serum aspartate or alanine aminotransferases occurred in four of the five chimpanzees, including the control chimpanzee, in direct association with ethanol infusion; pre‐existing enzyme elevations persisted in a fifth chimpanzee. No alteration occurred in the titers of hepatitis B surface antigen or of antibody to hepatitis B core antigen in three of the four infected chimpanzees. There was no significant alteration in the course of hepatitis B virus infection by ethanol infusion in these chimpanzees.
Association of normal serum protein antigens with chimpanzee hepatitis B surface antigen particles
Authors: Vnek John , Prince Alfred M. , Hashimoto Nobuo , Ikram Hafeez
Published: March 2007

HBsAg/adw was purified from 2.6 liters of pooled plasma from a single chimpanzee carrier by polyethylene glycol (PEG) precipitation followed by isopycnic and rate zonal centrifugation. The different morphological populations of HBsAg separated in the final rate zonal centrifugation step were combined into seven pools: two fractions rich in filaments and Dane particles, two pools composed of filaments and 20–28‐nm spheres, and three fractions containing mostly 20–28‐nm spheres.

The purified preparations of HBsAg analyzed for normal serum protein contaminants revealed albumin and traces of IgG. The same samples, analyzed after Tween‐80 treatment, revealed enhanced quantities of the previous two contaminants, and in addition, transferrin, traces of α2‐macroglobulin, IgM, and complement (C3/C3c). The residual contaminants were mostly removed by further purification and fractionation after detergent treatment using zone convection electrofocusing and rate zonal centrifugation.

Our findings indicate that conventional purification techniques will not provide preparations of HBsAg free of traces of serum protein contaminants. Many of these are released only by detergent treatments and subsequent purification. It is not yet clear whether detergents release these contaminants from the interior of the particles or from firm association or incorporation within the membranes.
CNS disease following dissemination of SSPE measles virus from intraperitoneal inoculation of suckling hamsters
Authors: Carrigan Donald R. , McKendall Robert R. , Johnson Kenneth P.
Published: March 2007

Acute encephalitis was observed in suckling Golden Syrian hamsters following intraperitoneal (ip) inoculation of a hamster brain adapted strain of subacute sclerosing panencephalitis (SSPE) measles virus (HBS). Virus was isolated from the brains of all encephalitic animals by cocultivation of tissue with Vero cells. The histopathology of the encephalitis was characterized by perivascular mononuclear infiltrates, necrosis, eosinophilic inclusion bodies, and rare giant cells. Association of encephalitis with systemic viral infection was observed with virus present in lung and a kidney‐spleen pool in addition to brain.

Viral dissemination in asymptomatic animals was documented with virus being isolated from multiple non‐neural tissues (spleen, lung, liver) of animals having no recoverable virus in their brains and no signs of encephalitis. Treatment of animals with cyclophosphamide prior to ip virus inoculation did not increase dissemination to brain. Absence of encephalitis in asymptomatic animals with proven viral dissemination to parenchymal organs indicates that neither viremia alone, nor viremia in conjunction with dissemination are sufficient conditions to establish central nervous system disease.

The association of encephalitis with systemic viral infection and the dissemination to brain establish this model's potential value for the study of the pathogenesis of measles encephalitis.