bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of the Oxyrase OxyPlate Anaerobe Incubation System
Authors: Wiggs Lois S. , Cavallaro Joseph J. , Miller J. Michael 
Published: December 2019

ABSTRACT

The Oxyrase OxyPlate anaerobe incubation system was evaluated for its ability to support the growth of clinically significant anaerobic bacteria previously identified by the Anaerobe Reference Laboratory at the Centers for Disease Control and Prevention. The results were compared with those obtained with conventional anaerobe blood agar plates incubated in an anaerobe chamber. We tested 251 anaerobic bacterial strains. Plates were read at 24, 48, and 72 h; growth was scored by a numerical coding system that combines the degree of growth and the colony size. Organisms (number of strains tested) used in this study were
Actinomyces
(32),
Anaerobiospirillum
(8),
Bacteroides
(39),
Campylobacter
(8),
Clostridium
(96),
Fusobacterium
(12),
Leptotrichia
(8),
Mobiluncus
(8),
Peptostreptococcus
(16), and
Propionibacterium
(24). At 24 h, 101 (40.2%) of the 251 strains tested showed better growth with the anaerobe chamber than with the OxyPlate system, 10 (4.1%) showed better growth with the OxyPlate system, and the remaining 140 (55.8%) showed equal growth with both systems. At 48 h, 173 (68.9%) showed equal growth with both systems, while 78 (31.1%) showed better growth with the anaerobe chamber. At 72 h, 176 (70.1%) showed equal growth with both systems, while 75 (29.9%) showed better growth with the anaerobe chamber. The OxyPlate system performed well for the most commonly isolated anaerobes but was inadequate for some strains. These results indicate that the Oxyrase OxyPlate system was effective in creating an anaerobic atmosphere and supporting the growth of anaerobic bacteria within 72 h. OxyPlates would be a useful addition to the clinical microbiology laboratory lacking resources for traditional anaerobic culturing techniques.
Detection of Carbapenemase-Producing
Acinetobacter baumannii
in a Hospital
Authors: Takahashi Ayako , Yomoda Sachie , Kobayashi Isao , Okubo Toyoji , Tsunoda Mitsuko , Iyobe Shizuko 
Published: December 2019

ABSTRACT

Acinetobacter baumannii
strains resistant to both imipenem (IPM) and ceftazidime (CAZ) were isolated from 1994 through 1996 at Gunma University Hospital. Nine isolates from different inpatients were examined for carbapenem-hydrolyzing activity and for the carbapemase gene
bla
IMP
by the PCR method. All nine isolates were carbapenemase-producing strains that hydrolyzed IPM and that harbored
bla
IMP
. The
bla
IMP
gene was transmissible by conjugation to an IPM-susceptible recipient strain of
A. baumannii
and conferred resistance to IPM, CAZ, cefotaxime (CTX), ampicillin (AMP), and piperacillin (PIP). Either intermediate or high-level resistance to amikacin (AMK) was transferred from two and five strains, respectively, concomitantly with
bla
IMP
, and gentamicin (GEN) resistance was also transferred in one instance of high-level AMK resistance. Comparative examination of clinical isolates for resistance patterns to nine drugs, IPM, CAZ, CTX, aztreonam, AMP, PIP, AMK, GEN, and norfloxacin, in addition to pulsed-field gel electrophoresis patterns with
Not
I-digested genomic DNA, confirmed nosocomial transmission of infections involving carbapenemase-producing
A. baumannii
strains.
Comparison of Sorbitol MacConkey Agar and a Two-Step Method Which Utilizes Enzyme-Linked Immunosorbent Assay Toxin Testing and a Chromogenic Agar To Detect and Isolate Enterohemorrhagic
Escherichia coli
Authors: Novicki Thomas J. , Daly Judy A. , Mottice Susan L. , Carroll Karen C. 
Published: December 2019

ABSTRACT

Enterohemorrhagic
Escherichia coli
(EHEC) and specifically serotype O157:H7 are a significant cause of hemorrhagic gastrointestinal disease and the hemolytic uremic syndrome. Methods currently used in clinical microbiology labs, such as sorbitol-MacConkey (SMAC) agar, reliably detect only O157:H7. We have evaluated a two-step method that has the potential to identify and isolate all EHEC serotypes, including serotype O157:H7. This method utilizes a chromogenic selective-differential medium for the isolation of
E. coli
together with an enzyme-linked immunosorbent assay (ELISA) that detects the Shiga-like toxins Stx1 and Stx2. Both are commercially available and usable in a wide range of clinical microbiology laboratories. Compared to a Vero cell cytotoxic assay, SMAC had sensitivities of 23.5% for the identification of all EHEC serotypes and of 50.0% for the identification of O157:H7 alone. The two-step method had sensitivities of 76.5 and 100%, respectively. The ELISA alone had a sensitivity of 82.4% in the detection of Stx1 and Stx2. The specificity was 100% in all cases. Overall, 14 EHEC isolates were obtained: 8 (58%) O157:H7, 2 (14%) O26, 2 (14%) O111:NM, 1 (7%) O103:H2, and 1 (7%) O121:H19. All but one were isolated during the months of May to September. The two-step method was found to be considerably more expensive than SMAC for both positive and negative samples.
Characterization of
Mycobacterium tuberculosis
Isolates from Patients in Houston, Texas, by Spoligotyping
Authors: Soini Hanna , Pan Xi , Amin Amol , Graviss Edward A. , Siddiqui Anees , Musser James M. 
Published: December 2019

ABSTRACT

Mycobacterium tuberculosis
isolates (
n
= 1,429) from 1,283 patients collected as part of an ongoing population-based tuberculosis epidemiology study in Houston, Texas, were analyzed by spoligotyping and IS
6110
profiling. The isolates were also assigned to one of three major genetic groups on the basis of nucleotide polymorphisms located at codons 463 and 95 in the genes (
katG
and
gyrA
) encoding catalase-peroxidase and the A subunit of DNA gyrase, respectively. A total of 225 spoligotypes were identified in the 1,429 isolates. There were 54 spoligotypes identified among 713 isolates (
n
= 623 patients) assigned to 73 IS
6110
clusters. In addition, among 716 isolates (
n
= 660 patients) with unique IS
6110
profiles, 200 spoligotypes were identified. No changes were observed either in the IS
6110
profile or in the spoligotype for the 281 isolates collected sequentially from 133 patients. Five instances in which isolates with slightly different spoligotypes had the same IS
6110
profile were identified, suggesting that in rare cases isolates with different spoligotypes can be clonally related. Spoligotypes correlated extremely well with major genetic group designations. Only three very similar spoligotypes were shared by isolates from genetic groups 2 and 3, and none was shared by group 1 and group 2 organisms or by group 1 and group 3 organisms. All organisms belonging to genetic groups 2 and 3 failed to hybridize with spacer probes 33 to 36. Taken together, the results support the existence of three distinct genetic groups of
M. tuberculosis
organisms and provide new information about the relationship between IS
6110
profiles, spoligotypes, and major genetic groups of
M. tuberculosis
.
Sequence Variation in the
ftsZ
Gene of
Bartonella henselae
Isolates and Clinical Samples
Authors: Ehrenborg C. , Wesslén L. , Jakobson Å. , Friman G. , Holmberg M. 
Published: December 2019

ABSTRACT

In a search for methods for subtyping of
Bartonella henselae
in clinical samples, we amplified and sequenced a 701-bp region in the 3′ end of the
ftsZ
gene in 15
B. henselae
isolates derived from cats and humans in the United States and Europe. The
ftsZ
sequence variants that were discovered were designated variants Bh
ftsZ
1, 2, and 3 and were compared with 16S rRNA genotypes I and II of the same isolates. There was no
ftsZ
gene variation in the strains of 16S rRNA type I, all of which were Bh
ftsZ
1. The type II strains constituted two groups, with nucleotide sequence variation in the
ftsZ
gene resulting in amino acid substitutions at three positions, one of which was shared by the two groups. One 16S rRNA type II isolate had an
ftsZ
gene sequence identical to those of the type I strains. Variants Bh
ftsZ
1 and 2 were detected in tissue specimens from seven Swedish patients with diagnoses such as chronic multifocal osteomyelitis, cardiomyopathy, and lymphadenopathy. Patients with similar clinical entities displayed either Bh
ftsZ
variant. The etiological role of
B. henselae
in these patients was supported by positive
Bartonella
antibody titers and/or amplification and sequencing of a part of the
B. henselae gltA
gene.
B. henselae ftsZ
gene sequence variation may be useful in providing knowledge about the epidemiology of various
B. henselae
strains in clinical samples, especially when isolation attempts have failed. This report also describes manifestations of atypical
Bartonella
infections in Sweden.
Use of Epidemiologically Well-Defined Subjects and Existing Immunofluorescence Assays To Calibrate a New Enzyme Immunoassay for Human Herpesvirus 8 Antibodies
Authors: Martin Jeffrey N. , Amad Zahwa , Cossen Cynthia , Lam Phung K. , Kedes Dean H. , Page-Shafer Kimberly A. , Osmond Dennis H. , Forghani Bagher 
Published: December 2019

ABSTRACT
Agreement between assays for the detection of human herpesvirus 8 (HHV-8) antibodies has been limited. In part, this disagreement has been because assay calibration (i.e., differentiating positive from negative results) has not been done in a standardized fashion with reference to a wide spectrum of HHV-8-infected (true-positive) and HHV-8-uninfected (true-negative) persons. To describe the performance of an assay for HHV-8 antibodies more accurately, we used epidemiologically well-characterized subjects in conjunction with testing on two existing immunofluorescence assays for HHV-8 antibodies to define two groups: a group of 135 HHV-8-infected individuals (true positives), including Kaposi's sarcoma patients and those asymptomatically infected, and a group of 234 individuals with a high likelihood of being HHV-8 uninfected (true negatives). A new enzyme immunoassay (EIA), using lysed HHV-8 virion as the antigen target, was then developed. With the above true positives and true negatives as references, the sensitivity and specificity of the EIA associated with different cutoff values were determined. At the cutoff that maximized both sensitivity and specificity, sensitivity was 94% and specificity was 93%. When the EIA was used to test a separate validation group, a distribution of seropositivity that matched that predicted for the agent of Kaposi's sarcoma was observed: 55% of homosexual men were seropositive, versus 6% seropositivity in a group of children, women, and heterosexual men. It is proposed that the EIA has utility for large-scale use in a number of settings and that the calibration method described can be used for other assays, both to more accurately describe the performance of these assays and to permit more-valid interassay comparison.
Comparison of Three Assays for Cytomegalovirus Detection in AIDS Patients at Risk for Retinitis
Authors: Wattanamano Pornthep , Clayton John L. , Kopicko Jeffrey J. , Kissinger Patricia , Elliot Steven , Jarrott Christine , Rangan Setlur , Beilke Mark A. 
Published: December 2019

ABSTRACT

The purpose of this study was to determine the sensitivity and specificity of three different methods of cytomegalovirus (CMV) detection for AIDS patients at risk for CMV retinitis. Patients with CD4
+
counts of <100/μl and negative baseline screening eye examinations were tested for CMV infection by (i) pp65 antigenemia expression in leukocytes, (ii) the Digene Hybrid Capture CMV DNA System, and (iii) the Roche Amplicor Qualitative PCR Test. The incidence of CMV retinitis in our study of 296 patients at the Medical Center of Louisiana—New Orleans HIV Outpatient Clinic was 7.2 per 100 person-years (a total of 20 episodes in 18 patients from April 1997 to February 1999). Receiver operating characteristic curves were calculated for each assay to determine optimal cutoff points which maximized the sensitivity and specificity of each assay. The sensitivities of the assays compared to the eye examinations were 80% for the pp65 antigenemia assay (cutoff, >0 cell per 1.5 × 10
5
leukocytes), 85% for the Digene assay (cutoff, 1,400 genome copies/ml of whole blood), and 60% for the Amplicor assay. The specificities of the assays were 84, 84, and 87%, respectively. The Digene assay with a cutoff of ≥1,400 genome copies/ml gave optimal sensitivity and specificity and was found to have predictive values equal to those of the more technically cumbersome antigenemia assay.
Differential Diagnosis of
Taenia saginata
and
Taenia solium
Infection by PCR
Authors: González Luis Miguel , Montero Estrella , Harrison Leslie J. S. , Parkhouse R. Michael E. , Garate Teresa 
Published: December 2019

ABSTRACT

We have designed species-specific oligonucleotides which permit the differential detection of two species of cestodes,
Taenia saginata
and
Taenia solium
. The oligonucleotides contain sequences established for two previously reported, noncoding DNA fragments cloned from a genomic library of
T. saginata
. The first, which is
T. saginata
specific (fragment HDP1), is a repetitive sequence with a 53-bp monomeric unit repeated 24 times in direct tandem along the 1,272-bp fragment. From this sequence the two oligonucleotides that were selected (oligonucleotides PTs4F1 and PTs4R1) specifically amplified genomic DNA (gDNA) from
T. saginata
but not
T. solium
or other related cestodes and had a sensitivity down to 10 pg of
T. saginata
gDNA. The second DNA fragment (fragment HDP2; 3,954 bp) hybridized to both
T. saginata
and
T. solium
DNAs and was not a repetitive sequence. Three oligonucleotides (oligonucleotides PTs7S35F1, PTs7S35F2, and PTs7S35R1) designed from the sequence of HDP2 allowed the differential amplification of gDNAs from
T. saginata
,
T. solium
, and
Echinococcus granulosus
in a multiplex PCR, which exhibits a sensitivity of 10 pg.
Rapid Identification of Bacteria in Blood Cultures by Using Fluorescently Labeled Oligonucleotide Probes
Authors: Jansen G. J. , Mooibroek M. , Idema J. , Harmsen H. J. M. , Welling G. W. , Degener J. E. 
Published: December 2019

ABSTRACT

The applicability of whole-cell hybridization for the identification of pathogenic bacteria in blood from septic patients was examined. Oligonucleotide probes, fluorescently labeled with fluorescein isothiocyanate, directed against the variable regions of the 16S rRNAs of the following bacterial species and/or genera were used:
Streptococcus
spp.,
Enterococcus faecalis
,
Staphylococcus aureus
, coagulase-negative staphylococci (CoNS),
Escherichia coli
,
Pseudomonas aeruginosa
, and the
Enterobacteriaceae
family. A probe specific for the rRNAs of almost all bacteria and its complementary, reversed counterpart was used as positive and negative control, respectively. The probes were used in conjunction with a fast and simple-to-use protocol for whole-cell hybridization. This protocol yields an identification after 25 to 45 min, depending on whether the bacterium is gram positive or gram negative. A total of 182 blood samples which tested positive in a blood culture machine were investigated. All probes except for the ones for
S. aureus
and the CoNS showed sensitivities and specificities of 1.000. It was concluded that whole-cell hybridization is well suited for the fast screening of septic blood containing streptococci and/or enterococci or gram-negative rods.
Fluorescent In Situ Hybridization Allows Rapid Identification of Microorganisms in Blood Cultures
Authors: Kempf Volkhard A. J. , Trebesius Karlheinz , Autenrieth Ingo B. 
Published: December 2019

ABSTRACT
Using fluorescent in situ hybridization (FISH) with rRNA-targeted fluorescently labelled oligonucleotide probes, pathogens were rapidly detected and identified in positive blood culture bottles without cultivation and biotyping. In this study, 115 blood cultures with a positive growth index as determined by a continuous-reading automated blood culture system were examined by both conventional laboratory methods and FISH. For this purpose, oligonucleotide probes that allowed identification of approximately 95% of those pathogens typically associated with bacteremia were produced. The sensitivity and specificity of these probes were 100%. From all 115 blood cultures, microorganisms were grown after 1 day and identification to the family, genus, or species level was achieved after 1 to 3 days while 111 samples (96.5%) were similarly identified by FISH within 2.5 h. Staphylococci were identified in 62 of 62 samples, streptococci and enterococci were identified in 19 of 20 samples, gram-negative rods were identified in 28 of 30 samples, and fungi were identified in two of two samples. Thus, FISH is an appropriate method for identification of pathogens grown in blood cultures from septicemic patients.
Heterogeneous Vancomycin Resistance in Methicillin-Resistant
Staphylococcus aureus
Strains Isolated in a Large Italian Hospital
Authors: Marchese A. , Balistreri G. , Tonoli E. , Debbia E. A. , Schito G. C. 
Published: December 2019

ABSTRACT

Of 179 methicillin-resistant
Staphylococcus aureus
strains isolated from 1997 to 1998, two strains (1.1%) gave subclones for which the vancomycin MICs were 8 mg/liter. Pulsed-field gel electrophoresis showed identical restriction patterns for both isolates, suggesting transfer of a single clone between two different patients.
Genetic Characterization of
Campylobacter jejuni
O:41 Isolates in Relation with Guillain-BarréSyndrome
Authors: Wassenaar Trudy M. , Fry Benjamin N. , Lastovica Albert J. , Wagenaar Jaap A. , Coloe Peter J. , Duim Birgitta 
Published: December 2019

ABSTRACT

Campylobacter jejuni
O:41 strains are found in association with Guillain-Barré syndrome in South Africa. Strains of this serotype collected over 17 years were characterized by amplified fragment length polymorphism and flagellin typing to determine their clonal nature. Despite minor variation in GM1 expression, all of the strains were genetically indistinguishable, indicating that they are representative of a genetically stable clone.
Epidemiology of Glycopeptide-Resistant Enterococci Colonizing High-Risk Patients in Hospitals in Johannesburg, Republic of South Africa
Authors: von Gottberg Anne , van Nierop Wim , Dusé Adriano , Kassel Marlene , McCarthy Kerrigan , Brink Adrian , Meyers Marilyn , Smego Raymond , Koornhof Hendrik 
Published: December 2019

ABSTRACT

Recent cases of infections caused by glycopeptide-resistant enterococci (GRE) have highlighted the emergence of these organisms in the Republic of South Africa. During May 1998 we conducted a prevalence study in four hospitals in Johannesburg and obtained 184 rectal swabs from patients identified as being at high risk for GRE colonization. Twenty enterococcal isolates showing various glycopeptide resistance genotypes were recovered: 3
Enterococcus faecium vanA
isolates, 10
E. faecium vanB
isolates, 6
E. gallinarum vanC1
isolates, and 1
E. avium vanA
isolate. Macrorestriction analysis was used to demonstrate the clonal spread of GRE strains within hospitals. Evidence also demonstrated the likely persistence of the original
E. faecium vanA
isolate associated with the first confirmed death contributed to by GRE infection in South Africa in March 1997.
Diagnostically and Experimentally Useful Panel of Strains from the
Burkholderia cepacia
Complex
Authors: Mahenthiralingam Eshwar , Coenye Tom , Chung Jacqueline W. , Speert David P. , Govan John R. W. , Taylor Peter , Vandamme Peter 
Published: December 2019

ABSTRACT

Two new species,
Burkholderia multivorans
and
Burkholderia vietnamiensis
, and three genomovars (genomovars I, III, and IV) currently constitute the
Burkholderia cepacia
complex. A panel of 30 well-characterized strains representative of each genomovar and new species was assembled to assist with identification, epidemiological analysis, and virulence studies on this important group of opportunistic pathogens.
Comparative Evaluation of Two Branched-DNA Human Immunodeficiency Virus Type 1 RNA Quantification Assays with Lower Detection Limits of 50 and 500 Copies per Milliliter
Authors: Manegold Christoph , Krempe Catharina , Jablonowski Helmut , Kajala Lasse , Dietrich Manfred , Adams Ortwin 
Published: December 2019

ABSTRACT

We have comparatively evaluated Quantiplex version 3.0 and version 2.0 on 133 plasma samples and a repetitive dilution series. Version 3.0 yielded higher human immunodeficiency virus RNA values, and the ratio of version 3.0 results to version 2.0 results decreased from 3.47 below 1,000 copies/ml to 1.97 above 50,000 copies/ml [linear regression, log (version 3.0) = 0.915 + 0.871 × log (version 2.0);
r
2
= 0.952].
Infection of a Hip Prosthesis by
Actinomyces naeslundii
Authors: Wüst Jürg , Steiger Ulrich , Vuong Hanh , Zbinden Reinhard 
Published: December 2019

ABSTRACT

We present the case of a 77-year-old woman who developed an
Actinomyces naeslundii
infection of a hip prosthesis. The isolate grew well aerobically with 5% CO
2
. Possible diagnostic problems may arise in the microbiological laboratory because aerobic growth is not sufficiently accounted for in some of the traditional identification schemes and commercial test kits. Therefore, besides presenting an unusual pathogen in this setting, this report focuses on possible diagnostic problems in the microbiological laboratory.
Multiplex PCR for Detection of Genes for
Staphylococcus aureus
Enterotoxins, Exfoliative Toxins, Toxic Shock Syndrome Toxin 1, and Methicillin Resistance
Authors: Mehrotra Manisha , Wang Gehua , Johnson Wendy M. 
Published: December 2019

ABSTRACT

A multiplex PCR assay for detection of genes for staphylococcal enterotoxins A to E (
entA
,
entB
,
entC
,
entD
, and
entE
), toxic shock syndrome toxin 1 (
tst
), exfoliative toxins A and B (
etaA
and
etaB
), and intrinsic methicillin resistance (
mecA
) was developed. Detection of
femA
was used as an internal positive control. The multiplex PCR assay combined the primers for
sea
to
see
and
femA
in one set and those for
eta
,
etb
,
tst
,
mecA
, and
femA
in the other set. Validation of the assay was performed using 176 human isolates of
Staphylococcus aureus
. This assay offers a very specific, quick, reliable, and inexpensive alternative to conventional PCR assays used in clinical laboratories to identify various staphylococcal toxin genes.
Evaluation of the Oricult-N Dipslide for Laboratory Diagnosis of Vaginal Candidiasis
Authors: Carlson Petteri , Richardson Malcolm , Paavonen Jorma 
Published: December 2019

ABSTRACT

The Oricult-N semiquantitative dipslide (Orion Diagnostica, Espoo, Finland) was evaluated for the laboratory diagnosis of vaginal candidiasis. It was compared with broth culture (Vagicult; Orion Diagnostica). Oricult-N was positive for 14.5% of 124 symptomatic patients and 12% of 50 asymptomatic controls. The results for broth cultures were 17 and 22%, respectively. Thus, the test group and the control group did not differ significantly by either method. High vaginal yeast counts (≥10
5
CFU/ml) were detected by Oricult-N in 7% of patients and in 0% of controls, but both groups harbored low numbers of yeasts. An accurate quantitative cutoff point separating a level of yeast associated with infection from vaginal yeast carriage could not be defined in the study. Nevertheless, the easy semiquantitation allowed by the Oricult-N method could be helpful because, especially in low-count carriers of
Candida
, other potential causes of vaginal symptoms should be considered. The Oricult-N method was technically simple and could be applied in primary health care. Further studies are required, however, before Oricult-N can be recommended as a routine diagnostic tool.