bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization ofToxoplasma gondiiSAG2 Expressed in Insect Cells by Recombinant Baculovirus and Evaluation of Its Diagnostic Potential in an Enzyme-Linked Immunosorbent Assay
Authors: Huang Xiaohong , Xuan Xuenan , Suzuki Hiroshi , Sugimoto Chihiro , Nagasawa Hideyuki , Fujisaki Kozo , Mikami Takeshi , Igarashi Ikuo 
Published: November 2002

ABSTRACTA baculovirus carrying the SAG2 gene ofToxoplasma gondiiwas constructed, and recombinant SAG2 protein (S-rSAG2) was expressed in insect cells. S-rSAG2 was recognized by sera from cats and pigs infected withT. gondii. Mice immunized with S-rSAG2 produced high titers of specific immunoglobulin G2a (IgG2a) and IgG1 antibodies. In an indirect fluorescent antibody test, all mouse antisera against S-rSAG2 reacted strongly to the natural parasites, but those against rSAG2 expressed inEscherichia coli(E-rSAG2) only showed very weak reaction, although no markedly difference was found in the reaction to denatured antigen,T. gondiilysate, in Western blot analysis. The results suggest that S-rSAG2 is better than E-rSAG2 in both antigenicity and immunogenicity. Enzyme-linked immunosorbent assay (ELISA) with S-rSAG2 could differentiate clearly between sera from 30 specific-pathogen-free cats and 4 experimentally infected cats. Serum samples from domestic cats in Japan were tested by the ELISA and compared with a latex agglutination test (LAT) and ELISA with E-rSAG2. Of 187 samples, all 35 LAT-positive sera had strong reactions to S-rSAG2 and E-rSAG2. Of the 152 LAT-negative sera, 18 were positive in the ELISA with S-rSAG2, whereas only 2 were positive in the ELISA with E-rSAG2. Although there were significant correlations among the three methods, the ELISA with S-rSAG2 was more sensitive than the others, which could be attributed to the fact that S-rSAG2 shares some common conformational structure with the native antigen. The results suggest that S-rSAG2 would be a useful reagent for the detection ofT. gondiiinfection in cats.
Humoral Immune Response Associated with Lyme Borreliosis in Nonhuman Primates: Analysis by Immunoblotting and Enzyme-Linked Immunosorbent Assay with Sonicates or Recombinant Proteins
Authors: Pachner A. R. , Dail D. , Li L. , Gurey L. , Feng S. , Hodzic E. , Barthold S. 
Published: November 2002

ABSTRACT

The immune response to
Borrelia burgdorferi
, the causative agent of Lyme disease, is complex. We studied the immunoglobulin M (IgM) and IgG antibody response to N40Br, a sensu stricto strain, in the rhesus macaque(nonhuman primate [NHP]) model of infection to identify the spirochetal protein targets of specific antibody. Antigens used in enzyme-linked immunosorbent assays were whole-cell sonicates of the spirochete and recombinant proteins of
B. burgdorferi
. Immunoblotting with a commercially available strip and subsequent quantitative densitometry of the bands were also used. Sera from four different groups of NHPs were used: immunocompetent, transiently immunosuppressed, extended immunosuppressed, and uninfected. In immunocompetent and transiently immunosuppressed NHPs, there was a strong IgM and IgG response. Major proteins for the early IgM response were P39 and P41 and recombinant BmpA and OspC. Major proteins for the later IgG response were P39, P41, P18, P60, P66, and recombinant BmpA and DbpA. There was no significant response in the NHPs to recombinant OspA or to Arp, a 37-kDa protein that elicits an antibody response during infection in mice. Most antibody responses, except for that to DbpA, were markedly diminished by prolonged dexamethasone treatment. This study supports the hypothesis that recombinant proteins may provide a useful adjunct to current diagnostic testing for Lyme borreliosis.
Fluorescence Polarization Assay for Detection of
Brucella abortus
Antibodies in Bulk Tank Bovine Milk Samples
Authors: Gall D. , Nielsen K. , Bermudez M. R. , Moreno F. , Smith P. 
Published: November 2002

ABSTRACT

A simple, rapid, inexpensive fluorescence polarization assay for the detection of antibodies to
Brucella abortus
in bulk tank milk samples at the farm level or at dairies with a sensitivity and specificity of 100 and 95.9%, respectively, is described. The assay detects antibodies to
B. abortus
in 15 min by testing undiluted whey produced by chemical and physical manipulation of milk from bulk tanks. This sampling is noninvasive and therefore costs less and is less stressful than blood-based tests. The assay is specific and can detect antibodies at levels below that of the indirect enzyme immunoassay for milk and the fluorescence polarization assay for individual milk samples. Use of this test would make programs for surveillance of dairy animals and eradication of
B. abortus
more cost-effective.
Interpretation of a Commercial Bovine Paratuberculosis Enzyme-Linked Immunosorbent Assay by Using Likelihood Ratios
Authors: Collins M. T. 
Published: November 2002

ABSTRACT

Evidence-based medicine encourages the use of quantitative diagnostic test results to estimate the probability of a particular diagnosis. Likelihood ratios (LRs) are among the best tools for maximizing the diagnostic information gained from diagnostic assays that provide results on a continuous scale. They provide the odds that an animal with a particular test result actually has the disease in question based on the magnitude of the test result. A commercial enzyme-linked immunosorbent assay (ELISA) was used to test sera from 143 dairy cattle infected with
Mycobacterium paratuberculosis
and 2,974 cattle free of this infection. This assay transforms ELISA reader optical density values into sample-to-positive (S/P) ratios. The LR was calculated for S/P results from 0.00 to 1.00 at 0.05-S/P unit intervals. LRs were directly but not linearly correlated with ELISA S/P ratios (
r
2
= 0.94). The mathematical function describing the relationship between the ELISA S/P ratio and the LR was LR = 265 × (S/P value)
2.03
. LRs were also directly related to the frequency of animals testing positive for paratuberculosis by fecal culture and other serologic tests. Based on these LRs, guidelines for interpretation and application of this ELISA for the diagnosis and control of paratuberculosis in dairy cattle herds are recommended.
Concentrations of Cytokines, Soluble Interleukin-2 Receptor, and Soluble CD30 in Sera of Patients with Hepatitis B Virus Infection during Acute and Convalescent Phases
Authors: Monsalve-de Castillo Francisca , Romero Tania A. , Estévez Jesús , Costa Luciana L. , Atencio Ricardo , Porto Leticia , Callejas Diana 
Published: November 2002

ABSTRACT

The immunoregulatory roles of interleukin-2 (IL-2), IL-4, IL-10, gamma interferon (IFN-γ), tumor necrosis factor alpha (TNF-α), the soluble form of the IL-2 receptor (sIL-2R), and the soluble form of CD30 (sCD30) were evaluated in patients with hepatitis B virus (HBV) infection. Two groups of subjects were studied: 15 healthy individuals without hepatitis antecedents and 15 patients with HBV infection. Blood samples were taken during the acute and convalescent phases. The analysis of the samples was done by the enzyme-linked immunosorbent assay technique. IFN-γ and TNF-α levels decreased in the convalescent phase. IL-10, IL-2, and sIL-2R levels increased in the acute and convalescent phases, while sCD30 levels increased during the acute phase. The IL-4 concentrations decreased in both phases. During the acute phase, IFN-γ and TNF-α induced increases in IL-2, sIL-2R, IL-10, and sCD30 levels in serum, which allowed the development of immunity characterized by the nonreactivity of the HBV surface antigen, the onset of antibodies to the HBV surface antigen (anti-HBs), and normal alanine aminotransferase levels during the convalescent phase. Increased IL-2 levels during the acute phase would stimulate the activities of NK cells and CD8
+
lymphocytes, which are responsible for viral clearing. The raised sIL-2R levels reveal activation of T lymphocytes and control of the IL-2-dependent immune response. The sCD30 increment during the acute phase reflects the greater activation of the Th2 cellular phenotype. Its decrease in the convalescent phase points out the decrease in the level of HBV replication. The increase in IL-10 levels could result in a decrease in IL-4 levels and modulate IFN-γ and TNF-α levels during both phases of disease, allowing the maintenance of anti-HBs concentrations.
Defibrination of Blood Plasma for Use in Serological Tests for Syphilis
Authors: Castro Arnold R. , Kikkert Susan E. , Fears Martha B. , Pope Victoria 
Published: November 2002

ABSTRACT

Syphilitic plasma can be salvaged from discarded blood donations and converted to serum by defibrination. Sixty-nine units of plasma were treated with a stock solution of 100 U of thrombin per ml in 1 M calcium chloride and then with a 10% (wt/vol) solution of kaolin. Fibrinogen concentrations detected in initial plasma samples ranged from 94 to 4,970 mg/liter (mean, 2,532 mg/liter) for samples that were reactive by the rapid plasma reagin circle card test (RPR) and from 314 to 2,742 mg/liter (mean 1,528 mg/liter) for samples that were not reactive by the RPR. The treated samples showed no measurable fibrinogen remaining after the defibrination process. In the nontreponemal RPR for syphilis, 86% of the treated plasma samples retained the same endpoint titer as that of the initial plasma sample. When the
Treponema pallidum
passive-particle-agglutination test was used, 98% retained the same reactivity. In the Captia Syphilis-G enzyme immunoassay, 89% of the treated samples demonstrated no change in reactivity index, and in the fluorescent treponemal antibody absorption test, 96% showed no reduction in fluorescence. Human sera containing antibodies to syphilis are used at the Centers for Disease Control and Prevention for the preparation of reference controls or as samples for proficiency testing. Finding reactive sera is becoming more difficult due to the general decline of syphilis cases in the United States. The decreasing availability of these sera can be alleviated by salvaging plasma and converting it to serum.
Use of a Single Monoclonal Antibody To Determine the Susceptibilities of Herpes Simplex Virus Type 1 and Type 2 Clinical Isolates to Acyclovir
Authors: Chutkowski Christine , Olson Betty , McDonough Ann , Mahoney James , McSharry James J. 
Published: November 2002

ABSTRACT
This report describes a flow cytometry drug susceptibility assay that uses a single fluorochrome-labeled monoclonal antibody to determine the acyclovir susceptibilities of herpes simplex virus (HSV) type 1 or type 2 clinical isolates. This assay yields 50% effective doses (drug concentrations that reduce the number of antigen-positive cells by 50%) for HSV clinical isolates that are equivalent to those obtained with the plaque reduction assay.
Differential Immune Response to the Variable Surface Loop Antigen of P66 of
Borrelia burgdorferi
Sensu Lato Species in Geographically Diverse Populations of Lyme Borreliosis Patients
Authors: Ornstein Katharina , Östberg Yngve , Bunikis Jonas , Noppa Laila , Berglund Johan , Norrby Ragnar , Bergström Sven 
Published: November 2002

ABSTRACT

We have studied the immune response to a variable surface-exposed loop region of the P66 outer membrane protein from
Borrelia burgdorferi
sensu lato by using an enzyme immunoassay. Lyme borreliosis populations found in North America and Sweden were preferentially more seroreactive to P66 from their respective regional species, namely,
B. burgdorferi
sensu stricto and
B. garinii
and
B. afzelii
, respectively.
Fully Automated Detection of Hepatitis C Virus RNA in Serum and Whole-Blood Samples
Authors: Kessler Harald H. , Clarici Alexandra M. K. , Stelzl Evelyn , Mühlbauer Gerhard , Daghofer Elisabeth , Santner Brigitte I. , Marth Egon , Stauber Rudolf E. 
Published: November 2002

ABSTRACT
In this study, we established a fully automated molecular assay for qualitative detection of hepatitis C virus (HCV) in serum and whole-blood samples and compared it with conventional molecular assays, including manual HCV RNA extraction protocols. Whole-blood samples were collected from patients with and without chronic HCV infection in EDTA tubes and nucleic acid stabilization tubes (NASTs). Prior to HCV RNA extraction, the HCV Internal Control (IC), derived from the COBAS AMPLICOR HCV test, version 2.0 (Roche Molecular Diagnostics), was added. The new assay was based on an automated extraction protocol on the MagNA Pure LC instrument (Roche Applied Science), followed by automated reverse transcription, amplification, hybridization, and detection on the Cobas Amplicor analyzer (Roche Molecular Diagnostics). The detection limit of the new assay was found to be similar to those of conventional molecular assays. In clinical samples, 100% agreement between the new assay and conventional methods was observed. The introduced amount of IC was detected in 45 of 45 serum samples, 41 of 45 EDTA tube whole-blood samples, and 43 of 45 NAST whole-blood samples. Retesting led to more frequent IC detection. The fully automated molecular assay was found to be suitable for detection of HCV RNA in different kinds of sample materials. It may be recommended for use in the high-throughput routine molecular diagnostic laboratory.
Prophylactic Effect ofMycobacterium bovisBCG Vaccination against Osteomyelitis in Children withMycobacterium ulceransDisease (Buruli Ulcer)
Authors: Portaels F. , Aguiar J. , Debacker M. , Steunou C. , Zinsou C. , Guédénon A. , Meyers W. M. 
Published: November 2002

ABSTRACTMycobacterium ulceransdisease, or Buruli ulcer (BU), causes significant morbidity in West Africa. In 233 consecutive, laboratory-confirmed samples from BU patients in Benin whoseMycobacterium bovisBCG scar status was known, 130 children (<15 years old) and 75 adults had a neonatal BCG vaccination scar. Of 130 children with BCG scars, 10 (7.7%) had osteomyelitis, while 3 of 9 children without BCG scars (33.3%) had osteomyelitis. Our observations support the conclusion that having a BCG vaccination scar provides significant protection againstM. ulceransosteomyelitis in children with BU disease.
In Vitro Detection of Apoptosis in Monocytes/Macrophages Infected with Human Coronavirus
Authors: Collins Arlene R. 
Published: November 2002

ABSTRACT

Human coronavirus (HCoV) strain 229E infection, but not HCoV strain OC43 infection, of monocytes/macrophages from healthy donors and patients with multiple sclerosis in remission resulted in increased apoptosis, as measured by DNA changes and annexin V staining. Apoptosis correlated with the differential release of infectious virus. HCoV strain 229E titers were 10
3.5
to 10
6
50% tissue culture-infective doses (TCID
50
)/ml, and HCoV strain OC43 titers were only 10
1.2
to 10
2.7
TCID
50
/ml.
Dichotomal Effect of the Coumadin Derivative Warfarin on Inflammatory Signal Transduction
Authors: Kater Arnon P. , Peppelenbosch Maikel P. , Brandjes Dees P. M. , Lumbantobing Mika 
Published: November 2002

ABSTRACTWarfarin, a widely prescribed drug for preventing thrombosis, is thought to act solely through inhibition of vitamin K-dependent coagulation factors. Low concentrations of warfarin inhibit interleukin-6 production and phosphorylation of I-κB but not activation of p38 mitogen-activated protein kinase. Thus, warfarin inhibits inflammatory signal transduction, and this may contribute to clinical effects of warfarin.
Coombs Antiglobulin Test Using
Brucella abortus
99 as Antigen To Detect Incomplete Antibodies Induced by
B. abortus
RB51 Vaccine in Cattle
Authors: Ciuchini Franco , Adone Rosanna , Pasquali Paolo 
Published: November 2002

ABSTRACT

This study showed that vaccination of cattle with
Brucella abortus
rough strain RB51 induces incomplete antibodies that can be detectable by a Coombs antiglobulin test using the
B. abortus
99 smooth strain.
Peptides Containing Cyclin/Cdk-Nuclear Localization Signal Motifs Derived from Viral Initiator Proteins Bind to DNA When Unphosphorylated
Authors: Kim Ronald J. , Moine Stephanie , Reese Danielle K. , Bullock Peter A. 
Published: November 2002

ABSTRACT
A single phosphorylation event at T-antigen residue Thr124 regulates initiation of simian virus 40 DNA replication. To explore this regulatory process, a series of peptides were synthesized, centered on Thr124. These peptides contain a nuclear localization signal (NLS) and a recognition site for cyclin/Cdk kinases. When unphosphorylated, the “CDK/NLS” peptides inhibit T-antigen assembly and bind non-sequence specifically to DNA. However, these activities are greatly reduced upon phosphorylation of Thr124. Similar results were obtained by using peptides derived from the CDK/NLS region of bovine papillomavirus E1. Related studies indicate that residues in the NLS bind to DNA, whereas those in the CDK motif regulate binding. These findings are discussed in terms of the control of T-antigen double hexamer assembly and initiation of viral replication.
Frequent Reassortments May Explain the Genetic Heterogeneity of Rotaviruses: Analysis of Finnish Rotavirus Strains
Authors: Maunula Leena , von Bonsdorff Carl-Henrik 
Published: November 2002

ABSTRACT
The predominant rotavirus electropherotypes (e-types) during 17 epidemic seasons (1980 through 1997) in Finland were established, and representative virus isolates were studied by nucleotide sequencing and phylogenetic analysis. The virus isolates were either P[8]G1 or P[8]G4 types. The G1 and G4 strains formed one G1 lineage (VP7-G1-1) and one G4 lineage, respectively. Otherwise, they belonged to two P[8] lineages (VP4-P[8]-1 and -2) unrelated to their G types. Phylogenetic analysis of partial sequences of all 11 RNA segments obtained from the strains also revealed genetic diversity among gene segments other than those defining P and G types. With the exception of segments 1, 3, and 10, the sequences of the other segments could be assigned to 2 to 4 different genetic clusters. The results of this study suggest that, in addition to the RNA segments encoding VP4 and VP7, the other RNA segments may segregate independently as well. In total, the 9 predominant e-types represented 7 different RNA segment combinations when the phylogenetic clusters of their 11 genes were determined. The extensive genetic diversity and number of e-types among rotaviruses are best explained by frequent genetic reassortment.
Amino Acid Residues in the Carboxy-Terminal Region of Cottontail Rabbit Papillomavirus E6 Influence Spontaneous Regression of Cutaneous Papillomas
Authors: Hu Jiafen , Cladel Nancy M. , Pickel Martin D. , Christensen Neil D. 
Published: November 2002

ABSTRACTPrevious studies have identified two different strains of cottontail rabbit papillomavirus (CRPV) that differ by approximately 5% in base pair sequence and that perform quite differently when used to challenge New Zealand White (NZW) rabbit skin. One strain caused persistent lesions (progressor strain), and the other induced papillomas that spontaneously regressed (regressor strain) at high frequencies (J. Salmon, M. Nonnenmacher, S. Caze, P. Flamant, O. Croissant, G. Orth, and F. Breitburd, J. Virol. 74:10766-10777, 2000; J. Salmon, N. Ramoz, P. Cassonnet, G. Orth, and F. Breitburd, Virology 235:228-234, 1997). We generated a panel of CRPV genomes that contained chimeric and mutant progressor and regressor strain E6 genes and assessed the outcome upon infection of both outbred and EIII/JC inbred NZW rabbits. The carboxy-terminal 77-amino-acid region of the regressor CRPV strain E6, which contained 15 amino acid residues that are different from those of the equivalent region of the persistent CRPV strain E6, played a dominant role in the conversion of the persistent CRPV strain to one showing high rates of spontaneous regressions. In addition, a single amino acid change (G252E) in the E6 protein of the CRPV progressor strain led to high frequencies of spontaneous regressions in inbred rabbits. These observations imply that small changes in the amino acid sequences of papillomavirus proteins can dramatically impact the outcome of natural host immune responses to these viral infections. The data imply that intrastrain differences between separate isolates of a single papillomavirus type (such as human papillomavirus type 16) may contribute to a collective variability in host immune responses in outbred human populations.
Inhibition of Polyomavirus
ori-
Dependent DNA Replication by mSin3B
Authors: Xie An-Yong , Folk William R. 
Published: November 2002

ABSTRACT

When tethered in
cis
to DNA, the transcriptional corepressor mSin3B inhibits polyomavirus (Py)
ori
-dependent DNA replication in vivo. Histone deacetylases (HDACs) appear not to be involved, since tethering class I and class II HDACs in
cis
does not inhibit replication and treating the cells with trichostatin A does not specifically relieve inhibition by mSin3B. However, the mSin3B L59P mutation that impairs mSin3B interaction with N-CoR/SMRT abrogates inhibition of replication, suggesting the involvement of N-CoR/SMRT. Py large T antigen interacts with mSin3B, suggesting an HDAC-independent mechanism by which mSin3B inhibits DNA replication.
Receptor-Induced Conformational Changes of Murine Coronavirus Spike Protein
Authors: Matsuyama Shutoku , Taguchi Fumihiro 
Published: November 2002

ABSTRACT

Although murine coronavirus mouse hepatitis virus (MHV) enters cells by virus-cell membrane fusion triggered by its spike (S) protein, it is not well known how the S protein participates in fusion events. We reported that the soluble form of MHV receptor (soMHVR) transformed a nonfusogenic S protein into a fusogenic one (F. Taguchi and S. Matsuyama, J. Virol.
76:
950-958, 2002). In the present study, we demonstrate that soMHVR induces the conformational changes of the S protein, as shown by the proteinase digestion test. A cl-2 mutant, srr7, of the MHV JHM virus (JHMV) was digested with proteinase K after treatment with soMHVR, and the resultant S protein was analyzed by Western blotting using monoclonal antibody (MAb) 10G, specific for the membrane-anchored S2 subunit. A 58-kDa fragment, encompassing the two heptad repeats in S2, was detected when srr7 was digested after soMHVR treatment, while no band was seen when the virus was untreated. The appearance of the proteinase-resistant fragment was dependent on the temperature and time of srr7 incubation with soMHVR and also on the concentration of soMHVR. Coimmunoprecipitation indicated that the direct binding of soMHVR to srr7 S protein induced these conformational changes; this was also suggested by the inhibition of the changes following pretreatment of soMHVR with anti-MHVR MAb CC1. soMHVR induced conformational changes of the S proteins of wild-type (wt) JHMV cl-2, as well as revertants from srr7, srr7A and srr7B; however, a major proportion of these S proteins were resistant to proteinase K even without soMHVR treatment. The implications of this proteinase-resistant fraction are discussed. This is the first report on receptor-induced conformational changes of the membrane-anchored fragment of the coronavirus S protein.