bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of the Vitek Gram-Positive Susceptibility 106 Card and the MRSA-Screen Latex Agglutination Test for Determining Oxacillin Resistance in Clinical Bloodstream Isolates of
Staphylococcus aureus
Authors: Yamazumi T. , Marshall S. A. , Wilke W. W. , Diekema D. J. , Pfaller M. A. , Jones Ronald N. 
Published: July 2002

ABSTRACT

The Vitek automated susceptibility testing system with a modified Gram-Positive Susceptibility (GPS) 106 Card (bioMerieux Vitek, Inc., Hazelwood, Mo.) and a rapid slide latex agglutination test (MRSA-Screen; Denka Seiken Co., Ltd., Tokyo, Japan) were evaluated for their ability to detect oxacillin resistance in
Staphylococcus aureus
. The oxacillin-salt agar screen (OS) test, the reference broth microdilution method, and the detection of the
mecA
gene by PCR were compared with the commercial products. A total of 200 contemporary (1999) bloodstream infection isolates were collected from the SENTRY Antimicrobial Surveillance Program, representing diverse geographic areas throughout the world. Among the 99
mecA
-positive isolates, 3 isolates were found negative by the MRSA-Screen. Another two isolates did not grow on OS plates and had MICs of 0.5 and 2 μg/ml with the Vitek GPS card. All 101
mecA
-negative isolates were also found negative by the MRSA-Screen and were categorized as susceptible by the GPS card. Overall, the MRSA-Screen, GPS card, and OS test had sensitivities of 96.9, 98.0, and 98.0% and specificities of 100.0, 100.0, and 98.0%, respectively. MRSA-Screen was a rapid (≤15 min) and simple test to perform, and the GPS card provided results in <8 h. Both methods were sensitive and specific for detecting staphylococcal oxacillin resistance in the clinical microbiology laboratory.
Quantitative Detection of Hepatitis B Virus DNA by Real-Time Nucleic Acid Sequence-Based Amplification with Molecular Beacon Detection
Authors: Yates Sol , Penning Maarten , Goudsmit Jaap , Frantzen Inge , van de Weijer Bert , van Strijp Dianne , van Gemen Bob 
Published: July 2002

ABSTRACT

We have developed a hepatitis B virus (HBV) DNA detection and quantification system based on amplification with nucleic acid sequence-based amplification (NASBA) technology and real-time detection with molecular beacon technology. NASBA is normally applied to amplify single-stranded target RNA, producing RNA amplicons. In this work we show that with modifications like primer design, sample extraction method, and template denaturation, the NASBA technique can be made suitable for DNA target amplification resulting in RNA amplicons. A major advantage of our assay is the one-tube, isothermal nature of the method, which allows high-throughput applications for nucleic acid detection. The homogeneous real-time detection allows a closed-tube format of the assay, avoiding any postamplification handling of amplified material and therefore minimizing the risk of contamination of subsequent reactions. The assay has a detection range of 10
3
to 10
9
HBV DNA copies/ml of plasma or serum (6 logs), with good reproducibility and precision. Compared with other HBV DNA assays, our assay provides good sensitivity, a wide dynamic range, and high-throughput applicability, making it a viable alternative to those based on other amplification or detection methods.
Alternative Identification Test Relying upon Sexual Reproductive Abilities of
Candida
lusitaniae
Strains Isolated from Hospitalized Patients
Authors: François Fabienne , Noël Thierry , Pépin Régis , Brulfert Annie , Chastin Christiane , Favel Anne , Villard Jean 
Published: July 2002

ABSTRACT

The in vitro mating ability of
Candida
lusitaniae
(teleomorph
Clavispora
lusitaniae
) clinical isolates has been investigated. Studying the effects of culture conditions, we showed that ammonium ion depletion in the medium is a major trigger of the sexual cycle. Moreover, a solid support is required for mating, suggesting a role for adhesion factors in addition to the mating type gene recognition function. Monitoring of mating and meiosis efficiency with auxotrophic strains showed great variations in ascospore yields, which appeared to be strain and temperature dependent, with an optimal range of 18 to 28°C. The morphogenetic events taking place from mating to ascospore release were studied by scanning and electron microscopy, and the ultrastructure of the conjugation canal, through which intercellular nuclear exchanges occur, was revealed. Labeling experiments with a lectin-fluorochrome system revealed that the nuclear transfer was predominantly polarized, thus allowing a distinction between the nucleus donor and the nucleus acceptor strains. The direction of the transfer depended on the strain combination used, rather than on the genotypes of the strains, and did not appear to be controlled by the mating type genes. Finally, we demonstrated that all of the 76 clinical isolates used in this study were able to reproduce sexually when mated with an opposite mating type strain, and we identified a 1:1
MAT
a/
MAT
α ratio in the collection. These results support the idea that there is no anamorph state in
C. lusitaniae
. Accordingly, the mating type test, which is easy to use and can usually be completed within 48 h, is a reliable alternative identification system for
C. lusitaniae
.
Molecular Evidence of Male-to-Female Sexual Transmission of Hepatitis C Virus after Vaginal and Anal Intercourse
Authors: Halfon Philippe , Riflet Hervé , Renou Christophe , Quentin Yves , Cacoub Patrice 
Published: July 2002

ABSTRACT
Hepatitis C virus (HCV) was transmitted from a chronic carrier to his female partner during unprotected anal and vaginal intercourse. Based on HVR1 and phylogenetic tree analysis, the couple had closely related isolates. These findings confirm sexual transmission of HCV without other risk factors.
Evaluation of Etest for Direct Antifungal Susceptibility Testing of Yeasts in Positive Blood Cultures
Authors: Chang Hsein Chang , Chang Jui Jung , Chan Shih Huang , Huang Ay Huey , Wu Tsu Lan , Lin Miao Chu , Chang Tsung Chain 
Published: July 2002

ABSTRACT

The performance of the Etest (AB BIODISK, Solna, Sweden) for direct antifungal susceptibility testing of yeasts in positive blood cultures was compared with that of the macrodilution method for determining the MICs of five antifungal agents. Culture broths with blood from bottles positive for yeasts were inoculated directly onto plates for susceptibility testing with the Etest, and the MICs were read after 24 and 48 h of incubation. A total of 141 positive blood cultures (72 cultures of
Candida albicans
, 31 of
Candida tropicalis
, 14 of
Candida glabrata
, 11 of
Candida parapsilosis
, 3 of
Candida krusei
, and 3 of
Cryptococcus neoformans
, 4 miscellaneous yeast species, and 3 mixed cultures) were tested, and the rates of MIC agreement (±1 log
2
dilution) between the direct Etest (at 24 and 48 h, respectively) and macrodilution methods were as follows: amphotericin B, 81.8 and 93.5%; flucytosine, 84.8 and 87.7%; fluconazole, 89.4 and 85.5%; itraconazole, 69.7 and 63.8%; ketoconazole, 87.9 and 79.0%. By a large-sample
t
test, the difference in log
2
dilution between the direct Etest and the macrodilution method was found to be small (
P
< 0.05). The lone exceptions were ketoconazole at 48 h of incubation and itraconazole at both 24 and 48 h of incubation (
P
> 0.05). By Tukey's multiple comparisons, the difference between the direct Etest (48 h) and reference methods among different species was found to be less than 1 log
2
dilution. When the MICs were translated into interpretive susceptibility, the minor errors caused by the direct Etest (at 24 and 48 h, respectively) were as follows: flucytosine, 2.3 and 1.4%; fluconazole, 3.0 and 3.6%; itraconazole, 21.2 and 21.3%. Itraconazole also produced an additional 3.0 and 3.6% major errors as determined by the direct Etest at 24 and 48 h, respectively. It was concluded that, except for itraconazole, the Etest method was feasible for direct susceptibility testing of blood cultures positive for yeasts. The method is simple, and the results could be read between 24 and 48 h after direct inoculation, whenever the inhibition zones were discernible.
Dynamics of a Nosocomial Outbreak of Multidrug-Resistant
Pseudomonas aeruginosa
Producing the PER-1 Extended-Spectrum β-Lactamase
Authors: Luzzaro Francesco , Mantengoli Elisabetta , Perilli Mariagrazia , Lombardi Gianluigi , Orlandi Viviana , Orsatti Alessandra , Amicosante Gianfranco , Rossolini Gian Maria , Toniolo Antonio 
Published: July 2002

ABSTRACT

From November 1998 to August 1999, a large outbreak occurred in the general intensive care unit of the Ospedale di Circolo in Varese (Italy), caused by
Pseudomonas aeruginosa
producing the PER-1 extended-spectrum β-lactamase. A total of 108 clinical isolates of
P. aeruginosa
resistant to broad-spectrum cephalosporins were recovered from 18 patients. Epidemic isolates were characterized by synergy between clavulanic acid and ceftazidime, cefepime, and aztreonam. Isoelectric focusing of crude bacterial extracts detected two nitrocefin-positive bands with pI values of 8.0 and 5.3. PCR amplification and characterization of the amplicons by restriction analysis and direct sequencing indicated that the epidemic isolates carried a
bla
PER-1
determinant. The outbreak was of clonal origin as shown by pulsed-field gel electrophoresis analysis. This technique also indicated that the epidemic strain was not related to three other PER-1-positive isolates obtained at the same hospital in 1997. Typing by enterobacterial repetitive intergenic consensus-PCR showed that minor genetic variations occurred during the outbreak. The epidemic strain was characterized by a multiple-drug-resistance phenotype that remained unchanged over the outbreak, including extended-spectrum cephalosporins, monobactams, aminoglycosides, and fluoroquinolones. Isolation of infected patients and appropriate carbapenem therapy were successful in ending the outbreak. Our report indicates that the
bla
PER-1
resistance determinant may become an emerging therapeutic problem in Europe.
Identification ofEhrlichiaspp. andBorrelia burgdorferiinIxodesTicks in the Baltic Regions of Russia
Authors: Alekseev Andrey N. , Dubinina Helen V. , Van De Pol Ingrid , Schouls Leo M. 
Published: July 2002

ABSTRACTThe presence and distribution ofEhrlichiaspp. andBorrelia burgdorferisensu lato was demonstrated among ixodid ticks collected in the Baltic regions of Russia, where Lyme borreliosis is endemic. A total of 3,426Ixodes ricinusand 1,267Ixodes persulcatusspecimens were collected, and dark-field microscopy showed that 265 (11.5%)I. ricinusand 333 (26.3%)I. persulcatusticks were positive. From these samples, 472 dark-field-positive and 159 dark-field-negative ticks were subjected to PCR and subsequent reverse line blot hybridization. Fifty-four ticks (8.6%) carriedEhrlichiaspecies, and 4 (0.6%) carried ehrlichiae belonging to theEhrlichia phagocytophilacomplex, which includes the human granulocytic ehrlichiosis agent. TheE. phagocytophilacomplex and anEhrlichia-like species were detected only inI. ricinuswhereasEhrlichia muriswas found exclusively inI. persulcatus, indicating a possible vector-specific infection.Borrelia gariniiwas found predominantly inI. persulcatus, butBorrelia afzeliiwas evenly distributed among the two tick species. Only twoI. ricinusticks carriedB. burgdorferisensu stricto, whileBorrelia valaisianaand a newly identifiedB. afzelii-like species were found in 1.7 and 2.5% of all ticks, respectively. Of the dark-field-positive ticks, only 64.8% yielded aBorreliaPCR product, indicating that dark-field microscopy may detect organisms other thanB. burgdorferisensu lato. These observations show that the agent of human granulocytic ehrlichiosis may be present in ticks in the Baltic regions of Russia and that clinicians should be aware of this agent as a cause of febrile disease.
Contamination of Catheter-Drawn Blood Cultures
Authors: Everts Richard J. , Vinson Emily N. , Adholla Paul O. , Reller L. Barth 
Published: July 2002

ABSTRACT

To assess the risk of contamination, we reviewed retrospectively 1,408 matched pairs of simultaneous catheter-drawn and venipuncture blood cultures. Catheter-drawn cultures were equally likely to be truly positive (14.4 versus 13.7%) but more likely to be contaminated (3.8 versus 1.8% [
P
= 0.001]). Direct venipuncture cultures are preferred.
Species-SpecificSerodiagnosis of Lyme Arthritis and Neuroborreliosis Due to
Borreliaburgdorferi
Sensu Stricto,
B. afzelii
, and
B.garinii
by Using Decorin Binding ProteinA
Authors: Heikkilä Tero , Seppälä Ilkka , Saxen Harri , Panelius Jaana , Yrjänäinen Heta , Lahdenne Pekka 
Published: July 2002

ABSTRACT

The antigenic potential of decorin binding protein A
(DbpA) was evaluated in serodiagnosis of human Lyme borreliosis (LB). The
dbpA
was cloned and sequenced from the three pathogenic
Borrelia
species common in Europe. Sequence analysis revealed high
interspecies heterogeneity. The identity of the predicted amino acid
sequences was 43 to 62% among
Borrelia burgdorferi
sensu stricto,
B. afzelii
, and
B. garinii
. The respective recombinant
DbpAs (rDbpAs) were produced and tested as antigens by Western blotting and
enzyme-linked immunosorbent assay (ELISA). One hundred percent of patients
with neuroborreliosis (NB) and 93% of patients with Lyme arthritis (LA)
reacted positively. Sera from the majority of patients reacted with one
rDbpA only and had no or low cross-reactivity to other two variant
proteins. In patients with culture-positive erythema migrans (EM), the
sensitivity of rDbpA immunoglobulin G (IgG) or IgM ELISA was low. The DbpA
seems to be a sensitive and specific antigen for the serodiagnosis of LA or
NB, but not of EM, provided that variants from all three pathogenic
borrelial species are included in the combined set of
antigens.
Rapid Identification of
Staphylococcus aureus
Directly from Blood Cultures by Fluorescence In Situ Hybridization with Peptide Nucleic Acid Probes
Authors: Oliveira Kenneth , Procop Gary W. , Wilson Deborah , Coull James , Stender Henrik 
Published: July 2002

ABSTRACT

A new fluorescence in situ hybridization (FISH) method with peptide nucleic acid (PNA) probes for identification of
Staphylococcus aureus
directly from positive blood culture bottles that contain gram-positive cocci in clusters (GPCC) is described. The test (the
S. aureus
PNA FISH assay) is based on a fluorescein-labeled PNA probe that targets a species-specific sequence of the 16S rRNA of
S. aureus.
Evaluations with 17 reference strains and 48 clinical isolates, including methicillin-resistant and methicillin-susceptible
S. aureus
species, coagulase-negative
Staphylococcus
species, and other clinically relevant and phylogenetically related bacteria and yeast species, showed that the assay had 100% sensitivity and 96% specificity. Clinical trials with 87 blood cultures positive for GPCC correctly identified 36 of 37 (97%) of the
S. aureus
-positive cultures identified by standard microbiological methods. The positive and negative predictive values were 100 and 98%, respectively. It is concluded that this rapid method (2.5 h) for identification of
S. aureus
directly from blood culture bottles that contain GPCC offers important information for optimal antibiotic therapy.
Direct Detection and Characterization of Shiga Toxigenic
Escherichia coli
by Multiplex PCR for
stx
1
,
stx
2
,
eae
,
ehxA
, and
saa
Authors: Paton Adrienne W. , Paton James C. 
Published: July 2002

ABSTRACT

We recently described a novel megaplasmid-encoded adhesin produced by certain Shiga toxigenic
Escherichia coli
(STEC) strains that lack the locus for enterocyte effacement (LEE) pathogenicity island. This adhesin, designated Saa (STEC autoagglutinating adhesin), may be a marker for a subset of LEE-negative STEC strains capable of causing severe gastrointestinal and systemic diseases in humans. In this study, we developed a pentavalent PCR assay for the detection of
saa
as well as other proven and putative STEC virulence genes (
stx
1
,
stx
2
,
eae
, and
ehxA
). The five primer pairs used in the assay do not interfere with each other and generate amplification products of 119, 180, 255, 384, and 534 bp.
Emergence of Penicillin-Nonsusceptible
Streptococcus pneumoniae
Invasive Clones in Canada
Authors: Greenberg D. , Speert D. P. , Mahenthiralingam E. , Henry D. A. , Campbell M. E. , Scheifele D. W. ,   the CPS/LCDC IMPACT Monitoring Network
Published: July 2002

ABSTRACT

Distinctive international clones of penicillin-nonsusceptible and multidrug-resistant
Streptococcus pneumoniae
are increasingly being reported. We investigated the spread of these clones in Canada through an active surveillance that was carried out at 11 Canadian pediatric tertiary care centers from 1991 to 1998. All penicillin-nonsusceptible isolates were serotyped, tested for antibiotic susceptibility, and genotyped by pulsed-field gel electrophoresis (PFGE) and random amplified polymorphic DNA (RAPD). Forty-five penicillin-nonsusceptible
S. pneumoniae
isolates were evaluated. Eleven serotype 9V isolates and six serotype 14 isolates displayed identical RAPD and PFGE fingerprint profiles. Twelve (70%) of these isolates were encountered in Quebec. The 9V/14 clone and the Spanish-French clone had similar PFGE fingerprint patterns. Eight isolates of serotype 23F and two isolates of serogroup 14 had the same fingerprint profiles and displayed resistance to three or more antibiotic drug classes. This clone was first detected in Calgary (Alberta) and in 1996 appeared simultaneously in various regions of Canada. This clone showed a PFGE fingerprint pattern similar to that of the Spanish-U.S. 23F clone. Our data show the emergence across Canada of two international clones of penicillin-nonsusceptible
S. pneumoniae
: (i) serotypes 9V and 14 related to the Spanish-French clone and (ii) the 23F Spanish-U.S. clone. The source of the first clone was in Quebec and the second international clone was probably originated from the United States. The exact reasons for the successful spread of these clones within Canada and their contribution to increased resistance to antibiotics have yet to be explored.
Sensitive PCR-Restriction Fragment Length Polymorphism Assay for Detection and Genotyping ofGiardia duodenalisin Human Feces
Authors: Amar C. F. L. , Dear P. H. , Pedraza-Díaz S. , Looker N. , Linnane E. , McLauchlin J. 
Published: July 2002

ABSTRACTAn assay that uses heminested PCR-restriction fragment length polymorphism analysis for the detection and genotyping ofGiardia duodenalison the basis of polymorphism in the triose phosphate isomerase (tpi) gene was developed. This assay was evaluated with DNA extracted from purified parasite material, bacterial cultures, whole human feces containingG. duodenalisand other parasites, and their corresponding immunofluorescence-stained fecal smears on glass microscope slides. The assay was specific and discriminated betweenG. duodenalisassemblages A and B. RFLP analysis further distinguished two groups (designated groups I and II) within assemblage A. Among 35 DNA samples extracted from whole feces from patients with confirmed sporadic giardiasis, thetpigene was amplified from 33 (94%). Of these, nine (27%) samples contained assemblage A group II, 21 (64%) contained assemblage B, and 3 (9%) contained a mixture of assemblage A group II and assemblage B. Thetpigene ofG. duodenalisassemblage B was amplified from 21 of 24 (88%) DNA samples extracted from whole feces from patients with confirmed cases of infection in a nursery outbreak. No amplification was detected from the remaining three DNA samples. Overall, analysis of DNA extracted from material recovered from stained microscope slides identified identicalG. duodenalisgenotypes in 35 (65%) of the 54 samples for which a genotype was established with DNA from whole feces. The heminested PCR method developed is sensitive, simple, and rapid to perform and is applicable for the analysis of other intestinal pathogens.
Evaluation of Dry and Wet Transported Intravaginal Swabs in Detection of
Chlamydia trachomatis
and
Neisseria gonorrhoeae
Infections in Female Soldiers by PCR
Authors: Gaydos Charlotte A. , Crotchfelt Kimberly A. , Shah Nina , Tennant Marie , Quinn Thomas C. , Gaydos Joel C. , McKee Kelly T. , Rompalo Anne M. 
Published: July 2002

ABSTRACT
Screening women for sexually transmitted diseases (STD) in nonclinic settings is highly desirable because many infections are asymptomatic. This is especially true for military women, for whom logistical, social, and other job-related obstacles present barriers to accessing medical care. We assessed the accuracy of intravaginal swabs transported by mail in a wet versus a dry state for PCR (Amplicor CT/NG test) detection of chlamydia and gonorrhea infections in a cross-sectional study of 793 active-duty military women attending an STD clinic. PCR tests of vaginal swabs (wet and dry) were compared to local clinical methods used on cervical swabs. Standard wet vaginal swab PCR testing detected more chlamydia (11.6%) than cervical enzyme immunoassay (9.3%). For detection of chlamydia using wet swabs, the sensitivity and specificity compared with adjudicated true positives were 94.6% (87 of 92) and 99.3% (696 of 701), respectively. Comparing dry swabs to true-positives for chlamydia, the sensitivity was 91.3% (84 of 92) and the specificity was 99.3% (696 of 701). Standard wet vaginal swab PCR detected more gonorrhea (3.3%) than routine cervical culture (2.1%). The sensitivity and specificity of PCR testing of wet swabs compared to true-positives (infected patients) were 96.3% (26 of 27) and 98.2% (752 of 766) for gonorrhea, respectively. For gonorrhea, the sensitivity and specificity of dry swabs compared to true-positives (infected patients) were 88.9% (24 of 27) and 98.3% (753 of 766), respectively. PCR testing of wet and dry transported intravaginal swabs to detect chlamydia and gonorrhea infections was an accurate diagnostic method for military women.
Enterococcus faecium
-Related Outbreak with Molecular Evidence of Transmission from Pigs to Humans
Authors: Lu Hong-Zhou , Weng Xin-Hua , Li Haijing , Yin You-Kuan , Pang Mao-Yin , Tang Yi-Wei 
Published: July 2002

ABSTRACT

Between 24 July and 31 August 1998, thousands of domestic pigs died of hemorrhagic shock in three adjunct counties along the YangZi River in Jiangshu Province, China. From 28 July to 6 September 1998, 40 local farmers (36 males and 4 females, ages 23 to 78 years) were hospitalized with severe illness characterized by high fever, erythematous rash or petechiae, and profound lethargy after contact with sick pigs. Twelve (30%) of these patients died of respiratory failure and shock. Eleven bacterial isolates recovered from 11 blood and cerebrospinal fluid specimens collected from seven patients and two pigs were identified as
Enterococcus faecium
based on biochemical reactions and 16S rRNA gene sequence analysis. Both pig and human
E. faecium
isolates displayed indistinguishable antibiotic susceptibility and pulsed-field gel electrophoresis patterns. These data strongly suggest the spread of an outbreak of
E. faecium
-related sepsis from pigs to humans.