bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of Four Commercial Immunoglobulin G (IgG)- and IgM-Specific Enzyme Immunoassays for Diagnosis of
Mycoplasma pneumoniae
Infections
Authors: Petitjean J. , Vabret A. , Gouarin S. , Freymuth F. 
Published: July 2002

ABSTRACT

The four following commercially available enzyme immunoassays (EIAs) were assessed and compared for their performance in detecting
Mycoplasma pneumoniae
immunoglobulin G (IgG)- and IgM-specific antibodies Platelia EIA, ImmunoWELL
M. pneumoniae
ELISA IgG and IgM, ETI-MP-IgG and IgM EIAs and Biotest anti-
M. pneumoniae
IgG and IgM ELISA (referred to herein as EIA-Platelia, EIA-BMD, EIA-Sorin, and EIA-Biotest). Three groups of patients were investigated: 39 patients (27 children and 12 adults) with respiratory infections who tested positive by PCR for
M. pneumoniae
in respiratory specimens (group I; 52 serum samples), 61 healthy children and adults (group II; 61 serum samples), and 20 patients with rheumatoid factor or antinuclear antibodies, or who tested positive for antiviral IgM (group III; 20 serum samples). In group III, the IgM specificity for EIA-Platelia, EIA-BMD, EIA-Biotest, and EIA-Sorin was 100, 90, 65, and 25%, respectively. In the children from group I, the four EIAs had similar IgM sensitivities (89 to 92%); the sensitivity for IgG was greater with EIA-BMD and EIA-Biotest than with EIA-Platelia and EIA-Sorin (66 and 78% versus 55 and 52%, respectively). In adult patients from group I, 9 to 10 serum samples were positive for IgG with a concordant sensitivity of 75 to 83% between the four EIAs but a striking difference in IgM sensitivity: 16% by EIA-Platelia and EIA-BMD, 50% by EIA-Biotest, and 58% by EIA-Sorin. Discrepant and unexpected results were observed in IgM detection from control healthy patients using EIA-Sorin and EIA-Biotest, confirming the lack of specificity of these two EIAs and making them inaccurate for routine diagnosis. A good concordance of IgG seroprevalence in healthy adults was found between the four EIAs (66 to 70%), though this concordance was lower with EIA-Platelia (43%). In healthy children, EIA-BMD and EIA-Biotest gave a higher IgG seroprevalence than EIA-Sorin and EIA-Platelia (45% each for the former compared to 17 and 20%, respectively, for the latter). These results confirm that the IgM EIA serology test is a valuable tool for the early diagnosis of
M. pneumoniae
infections in children, as long as the EIA used is specific. In adults, the difficult interpretation of EIAs suggests that paired sera, combined with PCR detection on respiratory tract specimens collected on admission of patient, should be required for accurate diagnosis.
Evaluation of a Strand Displacement Amplification Assay (BD ProbeTec-SDA) for Detection of
Neisseria gonorrhoeae
in Urine Specimens
Authors: Akduman Deniz , Ehret Josephine M. , Messina Kimberly , Ragsdale Sharron , Judson Franklyn N. 
Published: July 2002

ABSTRACT

The performance of a strand displacement amplification assay (the BDProbeTec-SDA assay) in detecting
Neisseria gonorrhoeae
in urine specimens was evaluated. When performed under stringent quality control conditions, the BDProbeTec-SDA assay is a sensitive, specific, and efficient method for the screening of large numbers of noninvasively obtained specimens. Because the predictive value of an assay is a function of the prevalence of the disease, culture confirmation is needed for samples with positive results from populations in which the prevalence of a disease is low or in situations in which false-positive results may have important medical, psychosocial, or medicolegal consequences.
Paracoccidioides
brasiliensis
87-Kilodalton Antigen, a Heat Shock Protein Useful in Diagnosis: Characterization, Purification, and Detection in Biopsy Material via Immunohistochemistry
Authors: Díez Soraya , Gómez Beatriz L. , Restrepo Angela , Hay Rod J. , Hamilton Andrew J. 
Published: July 2002

ABSTRACT

The 87-kDa antigen derived from the fungal pathogen
Paracoccidioides brasiliensis
can be detected in the sera of infected patients, and its levels have been shown to correlate well with response to treatment and with clinical cure. Despite its potential importance, the antigen has been poorly characterized. The 87-kDa antigen was purified to homogeneity via preparative gel electrophoresis; N-terminal amino acid sequencing revealed substantial homology with heat shock proteins (hsps) from a variety of organisms. A monoclonal antibody (MAb) raised against a
Histoplasma capsulatum
80-kDa hsp showed cross-reactivity to the purified 87-kDa antigen via Western blotting, and the 87-kDa-specific MAb P1B demonstrated that the antigen was expressed at higher levels in yeast than in mycelia by the same technique. Enzyme-linked immunosorbent assay and immunofluorescence reactivity using P1B confirmed increased expression of the 87-kDa antigen during the temperature-induced transformation of mycelia to yeast. Yeast-to-mycelium transformation was accompanied by a fall in expression, although the 87-kDa antigen was clearly constitutively expressed in both phases. Immunochemical staining of tissues from patients with MAb P1B who were infected with
P. brasiliensis
confirmed in vivo expression of the 87-kDa antigen by yeasts, and identification of this antigen via this method appears to be a useful adjunct to other methods used to diagnose paracoccidioidomycosis.
Evaluation of
Chlamydia pneumoniae
and
Mycoplasma pneumoniae
as Etiologic Agents of Persistent Cough in Adolescents and Adults
Authors: Wadowsky Robert M. , Castilla Elias A. , Laus Stella , Kozy Anita , Atchison Robert W. , Kingsley Lawrence A. , Ward Joel I. , Greenberg David P. 
Published: July 2002

ABSTRACT

Chlamydia pneumoniae
and
Mycoplasma pneumoniae
were evaluated as agents of persistent cough in adolescents and adults (
n
= 491). Tests of 473 respiratory specimens by culture or PCR or both identified four episodes (0.8%) of
M. pneumoniae
-associated illness and no episodes of
C. pneumoniae
illness, suggesting that these bacteria do not frequently cause persistent cough.
Soft Tissue Infection with
Absidia corymbifera
in a Patient with Idiopathic Aplastic Anemia
Authors: Cloughley R. , Kelehan J. , Corbett-Feeney G. , Murray M. , Callaghan J. , Regan P. , Cormican M. 
Published: July 2002

ABSTRACT

We describe a case of primary cutaneous mucormycosis (zygomycosis) in a patient with idiopathic aplastic anemia which responded to surgical debridement and therapy with liposomal amphotericin B. The tissue removed at surgery showed dense infiltration with fungal hyphae on histopathological examination. Primary cultures of tissue on solid media were negative, but
Absidia corymbifera
was isolated from unprocessed tissue placed in brain heart infusion broth.
Nine-Year Surveillance of Methicillin-ResistantStaphylococcus aureusin a Hospital Suggests Instability ofmecADNA Region in an Epidemic Strain
Authors: Donnio Pierre-Yves , Louvet Laurence , Preney Laure , Nicolas Denis , Avril Jean-Loup , Desbordes Laurent 
Published: July 2002

ABSTRACTThe distributions of the antibiotic resistance patterns in a population ofStaphylococcus aureusisolates from a teaching hospital were studied over a 9-year period. The results indicate the existence of successive major epidemic methicillin-resistant strains and the emergence of a methicillin-susceptible strain with an unusual resistance pattern. Our findings suggest that this methicillin-susceptibleS.aureusstrain could be derived from the dominant gentamicin-susceptible methicillin-resistantS.aureusstrain with the loss of a 40-kb DNA fragment.
Imported Visceral Leishmaniasis: Diagnostic Dilemmas and Comparative Analysis of Three Assays
Authors: Iqbal Jamshaid , Hira Parsotam R. , Saroj Grover , Philip Reeni , Al-Ali Faiza , Madda Patrick J. , Sher Ali 
Published: July 2002

ABSTRACT
The present study evaluates the performances of three noninvasive serological assays for the detection of immunoglobulin G antibodies to leishmania antigen for the diagnosis of imported cases of kala azar (visceral leishmaniasis [VL]) in a country, Kuwait, where the disease is not endemic. A total of 323 individuals including 21 patients with documented cases of VL, 72 individuals with suspected cases of VL, 155 patients with other parasitic infections, and 75 healthy control individuals were tested by indirect hemagglutination assay (IHA; Behring Diagnostics GmbH, Marburg, Germany), indirect fluorescent-antibody assay (IFA; bioMerieux sa, Marcy l'Etoile, France), and a qualitative membrane-based immunoassay with recombinant leishmania antigen K39 (strip-test; Intersep Ltd, Berkshire, United Kingdom). Our data show that IHA is the most sensitive test (100%), followed by IFA (86.6%) and the strip-test (80.0%). The strip-test was the most specific (100%) of the three assays, followed by IFA (93.0%) and IHA (86.0%). However, the strip-test failed to detect at least three confirmed cases of VL. We conclude that IHA is preferred over IFA and the strip-test for the screening of individuals with suspected cases of VL, especially in a country where VL is not endemic and where the number of cases is regular but limited. The details about some of the patients with VL are presented to highlight the diversity of clinical presentations and problems encountered in the diagnosis of VL in a country where VL is not endemic.
Genetic and Phenotypic Differences between
Legionella pneumophila
Strains
Authors: Samrakandi Mustapha M. , Cirillo Suat L. G. , Ridenour Dennis A. , Bermudez Luiz E. , Cirillo Jeffrey D. 
Published: July 2002

ABSTRACT

Legionnaires' disease is a potentially lethal pneumonia that is primarily due to infection by the species
Legionella
pneumophila
, although more than 40 other species are known. Certain
L
.
pneumophila
subgroups, particularly serogroup 1, are associated with the majority of the epidemics. The genetic bases for these differences in virulence have not been determined. Three strains, AA100, JR32, and Lp01, have been used in many molecular pathogenesis studies of
L
.
pneumophila
. We found genetic differences between these strains by PCR and Southern analyses that may be related to their ability to cause disease. We also examined the distribution of these genetic loci in clinical and environmental isolates of
Legionella
and found a correlation between the presence of two of these loci,
rtxA
and
lvh
, and the ability to cause disease in humans. Examination of the interactions of these strains with host cells suggested that they differ in important phenotypic characteristics including adherence, entry, and intracellular replication. Furthermore, in the mouse model of infection they display differing levels of replication in lungs. These studies emphasize the importance of further investigation into the genetic makeup of these strains, which is likely to lead to the identification of additional factors involved in
Legionella
pathogenesis.
DNA Microarray-Based Typing of an Atypical Monophasic
Salmonella enterica
Serovar
Authors: Garaizar Javier , Porwollik Steffen , Echeita Aurora , Rementeria Aitor , Herrera Silvia , Wong Rita Mei-Yi , Frye Jonathan , Usera Miguel A. , McClelland Michael 
Published: July 2002

ABSTRACT

A multidrug-resistant
fljB
-lacking
Salmonella enterica
serovar [4,5,12:i:−] emerged in Spain in 1997. We analyzed the genome from four strains of this serovar using a microarray containing almost all the predicted protein coding regions of serovar Typhimurium strain LT2, including the pSLT plasmid. Only a few differences from serovar Typhimurium LT2 were observed, suggesting the serovar to be Typhimurium as well. Six regions of interest were identified from the microarray data. Cluster I was a deletion of 13 genes, corresponding to part of the regulon responsible for the anaerobic assimilation of allantoin. Clusters II and IV were associated with the absence of the Fels-1 and Fels-2 prophage. Cluster III was a small group of Gifsy-1 prophage-related genes that appeared to be deleted or replaced. Cluster V was a deletion of 16 genes, including
iroB
and the operon
fljAB
, which is reflected in the serovar designation. Region VI was the gene STM2240, which appears to have an additional homologue in these strains. The regions spanning the deletions involving the allantoin operon and the
fljAB
operon were PCR amplified and sequenced. PCR across these regions may be an effective marker for this particular emergent serovar. While the microarray data for all isolates of the new serovar were essentially identical for all LT2 chromosomal genes, the isolates differed in their similarity to pSLT, consistent with the heterogeneity in plasmid content among isolates of the new serovar. Recent isolates have acquired a more-complete subset of homologues to this virulence plasmid. In general, microarrays can provide useful complementary data to other typing methods.
Identification by Phage Display and Characterization of Two Neutralizing Chimpanzee Monoclonal Antibodies to the Hepatitis E Virus Capsid Protein
Authors: Schofield D. J. , Glamann J. , Emerson S. U. , Purcell R. H. 
Published: July 2002

ABSTRACTTwo monoclonal antibodies (MAbs) against the ORF2 protein of the SAR-55 strain of hepatitis E virus (HEV) were isolated by phage display from a cDNA library of chimpanzee (Pan troglodytes) γ1/κ antibody genes. Both MAbs, HEV#4 and HEV#31, bound to reduced, denatured open reading frame 2 (ORF2) protein in a Western blot, suggesting that they recognize linear epitopes. The affinities (equilibrium dissociation constants,Kd) for the SAR-55 ORF2 protein were 1.7 nM for HEV#4 and 5.4 nM for HEV#31. The two MAbs also reacted in an enzyme-linked immunosorbent assay with recombinant ORF2 protein from a heterologous HEV, the Meng strain. Each MAb blocked the subsequent binding of the other MAb to homologous ORF2 protein in indirect competition assays, suggesting that they recognize the same or overlapping epitopes. Radioimmunoprecipitation assays suggested that at least part of the linear epitope(s) recognized by the two MAbs is located between amino acids 578 and 607. MAbs were mixed with homologous HEV in vitro and then inoculated into rhesus monkeys (Macaca mulatta) to determine their neutralizing ability. Whereas all control animals developed hepatitis (elevated liver enzyme levels in serum) and seroconverted to HEV, those receiving an inoculum incubated with either HEV#4 or HEV#31 were not infected. Therefore, each MAb neutralized the SAR-55 strain of HEV in vitro.
Reovirus Protein ςNS Binds in Multiple Copies to Single-Stranded RNA and Shares Properties with Single-Stranded DNA Binding Proteins
Authors: Gillian Anne Lynn , Schmechel Stephen C. , Livny Jonathan , Schiff Leslie A. , Nibert Max L. 
Published: July 2002

ABSTRACT

Reovirus nonstructural protein ςNS interacts with reovirus plus-strand RNAs in infected cells, but little is known about the nature of those interactions or their roles in viral replication. In this study, a recombinant form of ςNS was analyzed for in vitro binding to nucleic acids using gel mobility shift assays. Multiple units of ςNS bound to single-stranded RNA molecules with positive cooperativity and with each unit covering about 25 nucleotides at saturation. The ςNS protein did not bind preferentially to reovirus RNA over nonreovirus RNA in competition experiments but did bind preferentially to single-stranded over double-stranded nucleic acids and with a slight preference for RNA over DNA. In addition, ςNS bound to single-stranded RNA to which a 19-base DNA oligonucleotide was hybridized at either end or near the middle. When present in saturative amounts, ςNS displaced this oligonucleotide from the partial duplex. The strand displacement activity did not require ATP hydrolysis and was inhibited by MgCl
2
, distinguishing it from a classical ATP-dependent helicase. These properties of ςNS are similar to those of single-stranded DNA binding proteins that are known to participate in genomic DNA replication, suggesting a related role for ςNS in replication of the reovirus RNA genome.
Human Immunodeficiency Virus Type 1 Virion Density Is Not Determined by Nucleocapsid Basic Residues
Authors: Cimarelli Andrea , Luban Jeremy 
Published: July 2002

ABSTRACTThe human immunodeficiency virus type 1 (HIV-1) Gag polyprotein is sufficient for assembly and release of virion-like particles from the plasma membrane. To promote assembly, the Gag polyprotein must polymerize to form a shell that lines the inner membrane of nascent virions. Several techniques have been used to functionally map the domain required for Gag polymerization (the I domain). Among these methods, isopycnic centrifugation has been used under the assumption that changes in virion density reflect impairment in Gag-Gag interaction. If virion density is determined by efficient Gag-Gag interaction, then mutation of basic residues in the nucleocapsid (NC) domain should disrupt virion density, since these residues constitute the I domain. However, we have previously shown that simultaneous disruption of up to 10 HIV-1 NC basic residues has no obvious effect on virion density. To rule out the possibility that HIV-1 NC basic residues other than those previously mutated might be important for virion density, mutations were introduced at the remaining sites and the ability of these mutations to affect Gag-Gag interaction and virion density was analyzed. Included in our analysis is a mutant in which all NC basic residues are replaced with alanine. Our results show that disruption of HIV-1 NC basic residues has an enormous effect on Gag-Gag interaction but only a minimal effect on the density of those virions that are still produced. Therefore, the determinants of the I domain and of virion density are genetically distinguishable.
Effective Vaccine for Lassa Fever
Authors: Fisher-Hoch S. P. , Hutwagner L. , Brown B. , McCormick J. B. 
Published: July 2002

ABSTRACT
Lassa fever has been estimated to cause 5,000 deaths annually in West Africa. Recently, war in the zone where Lassa fever is hyperendemic has severely impeded control and treatment. Vaccination is the most viable control measure. There is no correlation between antibody levels and outcome in human patients, and inactivated vaccines produce high titers of antibodies to all viral proteins but do not prevent virus replication and death in nonhuman primates. Accordingly, we vaccinated 44 macaques with vaccinia virus-expressed Lassa virus structural proteins separately and in combination, with the object of inducing a predominantly TH1-type immune response. Following Lassa virus challenge, all unvaccinated animals died (0% survival). Nine of 10 animals vaccinated with all proteins survived (90% survival). Although no animals that received full-length glycoprotein alone had a high titer of antibody, 17 of 19 survived challenge (88%). In contrast, all animals vaccinated with nucleoprotein developed high titers of antibody but 12 of 15 died (20% survival). All animals vaccinated with single glycoproteins, G1 or G2, died, but all those that received both single glycoproteins (G1 plus G2) at separate sites survived, showing that both glycoproteins are independently important in protection. Neither group had demonstrable antibody levels prior to challenge. We demonstrate that in primates, immune responses to epitopes on both glycoproteins are required to protect against lethal challenge with Lassa virus without having untoward side effects and that this protection is likely to be primarily cell mediated. We show that an effective, safe vaccine against Lassa virus can and should be made and that its evaluation for human populations is a matter of humanitarian priority.
Short- and Long-Term Clinical Outcomes in Rhesus Monkeys Inoculated with a Highly Pathogenic Chimeric Simian/Human Immunodeficiency Virus
Authors: Endo Yasuyuki , Igarashi Tatsuhiko , Nishimura Yoshiaki , Buckler Charles , Buckler-White Alicia , Plishka Ronald , Dimitrov Dimiter S. , Martin Malcolm A. 
Published: July 2002

ABSTRACT

A highly pathogenic simian/human immunodeficiency virus (SHIV), SHIV
DH12R
, isolated from a rhesus macaque that had been treated with anti-human CD8 monoclonal antibody at the time of primary infection with the nonpathogenic, molecularly cloned SHIV
DH12
, induced marked and rapid CD4
+
T cell loss in all rhesus macaques intravenously inoculated with 1.0 50% tissue culture infective dose (TCID
50
) to 4.1 × 10
5
TCID
50
s of virus. Animals inoculated with 650 TCID
50
s of SHIV
DH12R
or more experienced irreversible CD4
+
T lymphocyte depletion and developed clinical disease requiring euthanasia between weeks 12 and 23 postinfection. In contrast, the CD4
+
T-cell numbers in four of five monkeys receiving 25 TCID
50
s of SHIV
DH12R
or less stabilized at low levels, and these surviving animals produced antibodies capable of neutralizing SHIV
DH12R
. In the fifth monkey, no recovery from the CD4
+
T cell decline occurred, and the animal had to be euthanized. Viral RNA levels, subsequent to the initial peak of infection but not at peak viremia, correlated with the virus inoculum size and the eventual clinical course. Both initial infection rate constants,
k
, and decay constants,
d
, were determined, but only the latter were statistically correlated to clinical outcome. The attenuating effects of reduced inoculum size were also observed when virus was inoculated by the mucosal route. Because the uncloned SHIV
DH12R
stock possessed the genetic properties of a lentivirus quasispecies, we were able to assess the evolution of the input virus swarm in animals surviving the acute infection by monitoring the emergence of neutralization escape viral variants.
Distinct Trafficking Pathways Mediate Nef-Induced and Clathrin-Dependent Major Histocompatibility Complex Class I Down-Regulation
Authors: Le Gall Sylvie , Buseyne Florence , Trocha Alicja , Walker Bruce D. , Heard Jean-Michel , Schwartz Olivier 
Published: July 2002

ABSTRACTThe human immunodeficiency virus type 1 Nef protein alters the post-Golgi stages of major histocompatibility complex class I (MHC-I) biogenesis. Presumed mechanisms involve the disclosure of a cryptic tyrosine-based sorting signal (YSQA) located in the cytoplasmic tail of HLA-A and -B heavy chains. We changed this signal for a prototypic sorting motif (YSQI or YSQL). Modified HLA-A2 molecules, termed A2-endo, displayed constitutively low surface levels and accumulated in a region close to or within the Golgi apparatus, a behavior reminiscent of wild-type HLA-A2 in Nef-expressing cells. However, several lines of evidence indicate that the action of prototypic signals on MHC-I trafficking differs from that of Nef. Internalization of surface A2-endo was more rapid and was associated with efficient recycling to the surface. A transdominant-negative mutant of dynamin-1 inhibited A2-endo constitutive internalization and Nef-induced CD4 down-regulation, whereas it did not affect the activity of Nef on MHC-I. Moreover, trafficking of A2-endo was still affected by the viral protein, indicating additive effects of prototypic signals and Nef. Therefore, distinct trafficking pathways regulate clathrin-dependent and Nef-induced MHC-I modulation.