bluuebunny/crossref_metadata_2025_split huggingface dataset:
Monoclonal Antibody against
Babesia equi
: Characterization and Potential Application of Antigen for Serodiagnosis
Authors: Avarzed Abgaandorjiin , Igarashi Ikuo , De Waal Daniel T. , Kawai Satoru , Oomori Yukio , Inoue Noboru , Maki Yoshiyuki , Omata Yoshitaka , Saito Atsushi , Nagasawa Hideyuki , Toyoda Yutaka , Suzuki Naoyoshi 
Published: December 2019

ABSTRACT

Monoclonal antibody (MAb) BEG3 was produced against
Babesia equi
parasites to define a species-specific antigen for diagnostic use. The MAb reacted with single, paired, and Maltese cross forms of
B. equi
, and no reaction was observed with this MAb on acetone-fixed
Babesia caballi
,
Babesia ovata
, or
Babesia microti
parasites in the indirect immunofluorescent antibody test. Confocal laser and immunoelectron microscopic studies showed that the antigen which was recognized by this MAb was located on the surface of
B. equi
parasites. This MAb recognized a 19-kDa protein of
B. equi
antigen and did not react with
B. caballi
antigen or normal horse erythrocytes in immunoblot analysis. This MAb also significantly inhibited the in vitro growth of the
B. equi
parasite. Preliminary studies using partially purified antigen, which was separated by high-pressure liquid chromatography and recognized by the MAb, suggested that it is a suitable antigen for enzyme-linked immunosorbent assay detection of anti-
B. equi
antibodies in naturally infected horse sera.
Characterization of Glycopeptide-Resistant Enterococci from a Swiss Hospital
Authors: Liassine Nadia , Frei Reno , Jan Isabelle , Auckenthaler Raymond 
Published: December 2019

ABSTRACT

Between August 1994 and September 1996, 28 glycopeptide-resistant enterococci (GRE) were isolated from 8 infected patients and 11 intestinal carriers hospitalized at the University Hospital of Geneva. Identification to the species was made by both phenotypic (API 20 STREP and Rapid ID 32 STREP systems, and Vitek Gram Positive Identification Card) and genotypic methods using a multiplex PCR assay developed also for the determination of the genotype of glycopeptide resistance (
vanA
,
vanB
,
vanC1
, and
vanC2-C3
genes). Fifteen isolates were identified as
Enterococcus faecium
, 8 as
E. gallinarum
, 4 as
E. faecalis
, and 1 as
E. hirae
. All of the phenotypic identification methods failed to differentiate some isolates of
E. gallinarum
from
E. faecium
, or vice versa. Both
vanA
(
n
= 18) and
vanB
(
n
= 4) glycopeptide resistance genotypes were found. For the first time, the
vanB
determinant was found in two isolates of
E. gallinarum
. Two patients were colonized by two different species containing the
vanA
gene and one by two different species containing the
vanB
gene. All
vanA
isolates were highly resistant to both vancomycin and teicoplanin except for three isolates which were susceptible to teicoplanin. Molecular typing by pulsed-field gel electrophoresis showed identical or similar patterns among
E. faecium
isolates with the
vanA
gene in five patients for whom the epidemiological link could not be always elucidated. This study emphasizes the necessity of utilizing both phenotypic and genotypic methods to characterize GRE.
Single-Step Multiplex PCR Assay for Characterization of New World
Leishmania
Complexes
Authors: Harris Eva , Kropp Gerald , Belli Alejandro , Rodriguez Betzabé , Agabian Nina 
Published: December 2019

ABSTRACT

We have developed a PCR assay for one-step differentiation of the three complexes of New World
Leishmania
(
Leishmania braziliensis
,
Leishmania mexicana
, and
Leishmania donovani
). This multiplex assay is targeted to the spliced leader RNA (mini-exon) gene repeats of these organisms and can detect all three complexes simultaneously, generating differently sized products for each complex. The assay is specific to the
Leishmania
genus and does not recognize related kinetoplastid protozoa, such as
Trypanosoma cruzi
,
Trypanosoma brucei
, and
Crithidia fasciculata
. It correctly identified
Leishmania
species with a broad geographic distribution in Central and South America. The sensitivity of the PCR amplification ranged from 1 fg to 10 pg of DNA (0.01 to 100 parasites), depending on the complex detected. Crude extracts of cultured parasites, prepared simply by boiling diluted cultures, served as excellent templates for amplification. Crude preparations of clinical material were also tested. The assay detected
L. braziliensis
in dermal scrapings from cutaneous leishmanial lesions,
Leishmania chagasi
in dermal scrapings of atypical cutaneous leishmaniasis, and
L. mexicana
from lesion aspirates from infected hamsters. We have minimized the material requirements and maximized the simplicity, rapidity, and informative content of this assay to render it suitable for use in laboratories in countries where leishmaniasis is endemic. This assay should be useful for rapid in-country identification of
Leishmania
parasites, particularly where different
Leishmania
complexes are found in the same geographical area.
Novel Method for Processing Respiratory Specimens for Detection of Mycobacteria by Using C
18
-Carboxypropylbetaine: Blinded Study
Authors: Thornton Charles G. , MacLellan Kerry M. , Brink Thomas L. , Lockwood Denise E. , Romagnoli Mark , Turner June , Merz William G. , Schwalbe Richard S. , Moody Marcia , Lue Yvonne , Passen Selvin 
Published: December 2019

ABSTRACT

A novel method for processing respiratory specimens to improve culture and acid-fast staining of mycobacteria is introduced. This new method utilized
N
,
N
-dimethyl-
N
-(
n
-octadecyl)-
N
-(3-carboxypropyl)ammonium inner salt (Chemical Abstract Service no. 78195-27-4), also known as C
18
-carboxypropylbetaine (CB-18). In a blinded, five-center study, CB-18-based processing was compared to the standard method combining NALC and NaOH (NALC/NaOH). A total of 573 respiratory specimens were tested. Individual specimens were split approximately equally; the host institutions processed half of each specimen by the NALC/NaOH method, while the other half was processed with CB-18 at Quest Diagnostics—Baltimore. A total of 106 specimens were culture positive for acid-fast bacilli (AFB). Replacement of the primary decontamination agent with CB-18 caused changes in all diagnostic parameters. Aggregate culture sensitivity improved by approximately 43% (
P
< 0.01), and smear sensitivity improved by approximately 58% (
P
< 0.01). The sensitivity of smear relative to that of
M. tuberculosis
isolates exceeded 93% (
P
< 0.01) when specimens were processed with CB-18. The average times to a positive result were reduced by 7.3 days in liquid culture (
P
< 0.01) and 5.3 days on solid media (
P
< 0.05); however, the CB-18 method had a 20.8% contamination rate in liquid culture versus a rate of approximately 7.5% with NALC/NaOH processing. There were also unusual reductions in liquid culture sensitivity and smear specificity among CB-18-processed specimens. The characteristics of the latter parameters suggested that refinement of the CB-18 processing method should allow further improvements in culture sensitivity. This study showed that the CB-18 method has the potential to improve both smear and culture detection for these important human pathogens.
Low-Level Viremia and Intracellular Expression of Hepatitis B Surface Antigen (HBsAg) in HBsAg Carriers with Concurrent Hepatitis C Virus Infection
Authors: Chu Chia-Ming , Yeh Chau-Ting , Liaw Yun-Fan 
Published: December 2019

ABSTRACT
Assays of hepatitis B virus (HBV) replication and antigen expression in HBV surface antigen (HBsAg) carriers with concurrent hepatitis C or D virus (HCV or HDV) infection revealed that HCV and HDV can suppress HBV replication but that HCV also substantially suppresses HBV surface protein expression. HBsAg carriers with concurrent HCV infection thus have low-level viremia and intracellular HBsAg.
Borna Disease in a Dog with Lethal Meningoencephalitis
Authors: Weissenböck Herbert , Nowotny Norbert , Caplazi Patrick , Kolodziejek Jolanta , Ehrensperger Felix 
Published: December 2019

ABSTRACT
A dog was euthanatized because of progressive neurological signs. Histologically, a nonsuppurative meningoencephalitis was found. By immunohistochemistry, in situ hybridization, and nested PCR procedures, Borna disease virus (BDV) antigen and BDV-specific RNA were demonstrated in brain tissues of the dog. The nucleotide sequence of the PCR product showed 94 to 98% homology to published BDV sequences. This is the first description of Borna disease in a dog.
Experimental Transmission ofEhrlichia equito Horses through Naturally Infected Ticks (Ixodes pacificus) from Northern California
Authors: Reubel Gerhard H. , Kimsey Robert B. , Barlough Jeffrey E. , Madigan John E. 
Published: December 2019

ABSTRACTWe report the experimental transmission ofEhrlichia equifrom naturally infectedIxodes pacificusticks to horses. Three weeks after exposure to ticks, two of three horses developed clinical signs compatible withE. equiinfection, while one horse remained asymptomatic. 16S rRNA gene PCR of blood leukocyte lysates was positive for all horses at various time points; two horses seroconverted. The 16S rRNA gene sequences amplified from tick-exposed horses showed more than 99% homology to corresponding fragments of the 16S rRNA genes ofE. equi,Ehrlichia phagocytophila, and the human granulocytic ehrlichiosis agent.
Clinical Evaluation of the Gen-Probe Amplified Direct Test for Detection of
Mycobacterium tuberculosis
Complex Organisms in Cerebrospinal Fluid
Authors: Lang Anne M. , Feris-Iglesias Jesus , Pena Chabela , Sanchez Jacqueline F. , Stockman Leslie , Rys Paul , Roberts Glenn D. , Henry Nancy K. , Persing David H. , Cockerill Franklin R. 
Published: December 2019

ABSTRACT

Eighty-four cerebrospinal fluid (CSF) samples from different children who presented with signs and symptoms of meningitis were evaluated for the presence of
Mycobacterium tuberculosis
complex organisms by the Gen-Probe Amplified
Mycobacterium tuberculosis
Direct Test (MTD; Gen-Probe, San Diego, Calif.). All CSF samples had negative acid-fast smears by the Ziehl-Neelsen staining method.
M. tuberculosis
was recovered from five samples.
M. tuberculosis
did not grow from 19 additional samples, but the samples were from patients who fulfilled specific clinical and laboratory criteria for probable tuberculous meningitis (TBM). The remaining samples (
n
= 60) were from patients with other infections or noninfectious causes of meningitis. The results of the MTD were interpreted as positive or negative on the basis of recommended cutoff values for respiratory specimens. These results were interpreted as true or false positives or true or false negatives on the basis of the results of
M. tuberculosis
culture or whether the patient fulfilled criteria for probable TBM. The Gen-Probe MTD was 33% sensitive and 100% specific for detecting
M. tuberculosis
complex organisms in these 84 CSF samples. If the cutoff values for positive results were decreased for the MTD (≥11,000 versus ≥30,000 relative light units), the sensitivity increased to 83% and the specificity remained 100%. These results for the MTD are encouraging considering that TBM is a highly fatal disease and difficult to diagnose by conventional laboratory techniques.
Etiological Study of Diarrheal Patients in Vientiane, Lao People’s Democratic Republic
Authors: Yamashiro Tetsu , Nakasone Noboru , Higa Naomi , Iwanaga Masaaki , Insisiengmay Sithat , Phounane Traykhouane , Munnalath Khampheuy , Sithivong Noikaseumsy , Sisavath Lay , Phanthauamath Boonang , Chomlasak Khampheng , Sisulath Phonsamay , Vongsanith Praseunthong 
Published: December 2019

ABSTRACT

The etiological agents of diarrhea in Vientiane, Lao People’s Democratic Republic (Lao PDR), were studied in the period from October 1996 to August 1997. A total of 880 patients with diarrhea visiting medical facilities were examined for
Shigella
,
Salmonella
, diarrheagenic
Escherichia coli
,
Vibrio
,
Aeromonas
,
Campylobacter
, and rotavirus.
Shigella
spp., heat-stable enterotoxin (ST)-producing
E. coli
, and serogroup-based enteropathogenic
E. coli
were found to be the main organisms causing diarrhea in Vientiane, with frequencies of 16.8% (148 of 880), 17.2% (111 of 645), and 11.0% (97 of 880), respectively. Relatively low incidences were observed in the cases of
Salmonella
spp., (0.6%; 5 of 880),
Campylobacter
spp. (4.4%; 39 of 880), and rotavirus (6.1%; 9 of 148), and no isolates of
V. cholerae
O1 or O139 or
Aeromonas
were recovered. An analysis of the incidences of enteropathogens with respect to age and seasonal variations demonstrated that the frequencies of isolation of
Shigella
spp. and heat-labile enterotoxin-producing
E. coli
were significantly higher in those aged 1 to 5 years than in those younger than 1 year of age and those older than 5 years of age (
P
< 0.0001 and
P
< 0.05, respectively) and that the frequencies of isolation of
Shigella
spp. and ST-producing
E. coli
were significantly higher in the rainy season than in the dry season (
P
< 0.005 and
P
< 0.001, respectively). Almost all strains of
Shigella
spp. tested were resistant to ampicillin, tetracycline, and erythromycin and were susceptible to cefdinir and ofloxacin. This is the first intensive and longitudinal study to define the etiologic agents of diarrheal diseases in Lao PDR.
Isolation ofKlebsiella planticolafrom Newborns in a Neonatal Ward
Authors: Podschun R. , Acktun H. , Okpara J. , Linderkamp O. , Ullmann U. , Borneff-Lipp M. 
Published: December 2019

ABSTRACTThis is the first report on the isolation ofKlebsiella planticolafrom neonates. Over a period of 1 year, oropharyngeal and rectal swab specimens from 131 newborns on a neonatal ward were monitored forKlebsiellaspp. Thirteen strains ofK. planticolacould be isolated, and these represented 9% of allKlebsiellaspp. found. Capsule type K27 predominated, followed by capsule type K68. Our findings suggest a significant rate of colonization byK. planticolaamong neonates.
Characterization of
Neisseria meningitidis
Strains Causing Disease in Complement-Deficient and Complement-Sufficient Patients
Authors: Fijen C. A. P. , Kuijper E. J. , Dankert J. , Daha M. R. , Caugant D. A. 
Published: December 2019

ABSTRACT
Serotyping and serosubtyping of meningococci showed no difference between isolates from 44 complement-deficient persons and from 50 complement-sufficient persons with meningococcal disease. Multilocus enzyme electrophoretic typing of the meningococci revealed 54 electrophoretic types that were equally distributed among isolates from complement-deficient and complement-sufficient patients. Analysis of strains isolated from eight complement-deficient persons with 11 recurrences of meningococcal disease showed that one strain was identical to the strain previously isolated from the same individual. Our results indicate that there are no differences between the clonal distributions of strains infecting complement-deficient and complement-sufficient patients. Most recurrences were infections caused by different strains.
Competitive PCR for Quantification of BM5d Proviral DNA in Mice with AIDS
Authors: Casabianca Anna , Vallanti Giuliana , Magnani Mauro 
Published: December 2019

ABSTRACT
Murine AIDS in C57BL/6 mice is caused by a unique mixture of murine leukemia viruses. We report the use of a competitive PCR to detect and quantitate BM5d proviral DNA. This assay allowed discrimination among endogenous wild-type murine retroviruses and BM5d sequences. Furthermore, the method was subsequently used to evaluate the amount of BM5d in infected mice and in infected AZT (zidovudine)-treated mice, providing an effective way to quantitatively evaluate drug efficacy in the murine AIDS model.
Evaluation of the RapID CB Plus System for Identification of Coryneform Bacteria andListeriaspp
Authors: Funke Guido , Peters Katja , Aravena-Roman Max 
Published: December 2019

ABSTRACTIn a stress test, the recently introduced RapID CB Plus system (Remel Inc. [formerly Innovative Diagnostic Systems], Norcross, Ga.) was challenged with a diverse set of gram-positive rods comprising 345 strains of coryneform bacteria and 33 strains ofListeriaspp. representing a total of 49 different taxa. Overall, within 4 h, the system correctly identified 80.9% of the strains on the species level and 12.2% of the strains on the genus level. Only 3.7% strains were misidentified, and for 3.2% of the strains no identification was provided. Difficulties with the system were mainly due to occasional uncertainties in reading reactions for acid production from carbohydrates and, to a lesser extent, aminopeptidase reactions. It is concluded that the system may also perform well under the conditions of a routine clinical laboratory.
Development of a PCR-Restriction Fragment Length Polymorphism Assay Using the Nucleotide Sequence of the
Helicobacter hepaticus
Urease Structural Genes
ureAB
Authors: Shen Zeli , Schauer David B. , Mobley Harry L. T. , Fox James G. 
Published: December 2019

ABSTRACT

Infection with
Helicobacter hepaticus
causes chronic active hepatitis in certain strains of mice and is associated with hepatocellular carcinoma in A/JCr mice. Like the gastric helicobacters,
H. pylori
and
H. mustelae
,
H. hepaticus
possesses a high level of urease activity. However, the
H. hepaticus
urease structural gene sequences have not been previously determined, and the role of the urease enzyme in colonization and in pathogenesis is not known. PCR was used to amplify a portion of the urease structural genes from
H. hepaticus
genomic DNA. Amplified DNA fragments were cloned, and the nucleotide sequence was determined. The deduced amino acid sequence of the partial
H. hepaticus ureA
gene product was found to exhibit 60% identity and 75% similarity to the predicted
H. pylori
UreA. The deduced amino acid sequence of a partial
H. hepaticus ureB
gene product exhibited 75% identity and 87% similarity to the predicted
H. pylori
UreB. Diversity among
H. hepaticus
isolates was evaluated by means of a restriction fragment length polymorphism (RFLP) assay. The 1.6-kb fragments within the
ureAB
open reading frames, amplified from 11 independent isolates, were digested with the restriction endonuclease
Hha
I. Three distinct RFLP patterns were observed. Identical RFLP profiles were noted in sequential isolates of one strain of
H. hepaticus
during an 18 month in vivo colonization study, suggesting that the urease genes of
H. hepaticus
are stable. The urease genes among
H. hepaticus
strains were also well conserved, showing 98.8 to 99% nucleotide sequence identity among three isolates analyzed. These findings indicate that
H. hepaticus
has urease structural genes which are homologous to those of the gastric
Helicobacter
species and that these gene sequences can be used in a PCR and RFLP assay for diagnosis of this important murine pathogen.
Cat Scratch Disease: the Rare Role of
Afipia felis
Authors: Giladi Michael , Avidor Boaz , Kletter Yehudith , Abulafia Suzy , Slater Leonard N. , Welch David F. , Brenner Don J. , Steigerwalt Arnold G. , Whitney Anne M. , Ephros Moshe 
Published: December 2019

ABSTRACT

Since its isolation in 1988,
Afipia felis
has been associated with cat scratch disease (CSD) in only one report and its role in CSD has been questioned. We have cultured
A. felis
from a lymph node of a patient with CSD. 16S rRNA gene sequencing, DNA relatedness studies, fatty acid analysis, and PCR of the
A. felis
ferredoxin gene showed that the isolate is identical to the previously reported
A. felis
isolate. To determine the role of
A. felis
in CSD, PCR of the 16S rRNA gene followed by hybridizations with specific probes were performed with lymph node specimens from CSD patients. All 32 specimens tested positive for
Bartonella henselae
and negative for
A. felis
. We conclude that
A. felis
is a rare cause of CSD. Diagnostic tests not conducive to the identification of
A. felis
might cause the diagnosis of CSD due to
A. felis
to be missed.
Chronic Prosthetic Hip Infection Caused by a Small-Colony Variant of
Escherichia coli
Authors: Roggenkamp Andreas , Sing Andreas , Hornef Mathias , Brunner Ulrich , Autenrieth Ingo B. , Heesemann Jürgen 
Published: December 2019

ABSTRACT

From two different specimens of a chronic prosthetic hip infection taken at an interval of 2 months a slow-growing gram-negative bacterium was isolated in pure culture. The strain grew with the typical features of a small-colony variant (SCV). 16S rRNA sequencing identified the bacterium as
Escherichia coli
. Biochemical characterization demonstrated multiple phenotypic alterations of a mutant carrying a defect in the heme biosynthetic pathway (Hem
−
): (i) catalase and nitrate reductase reactions were both negative, (ii) a negative benzidine reaction demonstrated the lack of heme-containing cytochromes, and (iii) growth stimulation under anaerobic conditions as well as gentamicin resistance indicated defective aerobic respiration. PCR and Southern hybridization demonstrated that the mutation of the SCV of
E. coli
was localized in the
hemB
gene and was most likely due to a deletion of the
hemB
gene. On blood agar plates revertants were recognized growing as normal-sized colonies between the dominant small colonies of the strain. Feeding experiments indicated that the revertants but not the small colonies were permeable for hemin. A strong antibody response against the infecting SCV of
E. coli
was found. To our knowledge, this is the first report of a Hem
−
E. coli
strain as the etiological agent of a chronic bacterial infection.
Species Identification and Virulence Attributes of
Saccharomyces boulardii
(nom. inval.)
Authors: McCullough Michael J. , Clemons Karl V. , McCusker John H. , Stevens David A. 
Published: December 2019

ABSTRACT

Saccharomyces boulardii
(nom. inval.) has been used for the treatment of several types of diarrhea. Recent studies have confirmed that
S. boulardii
is effective in the treatment of diarrhea, in particular chronic or recurrent diarrhea, and furthermore that it is a safe and well-tolerated treatment. The aim of the present study was to identify strains of
S. boulardii
to the species level and assess their virulence in established murine models. Three strains of
S. boulardii
were obtained from commercially available products in France and Italy. The three
S. boulardii
strains did not form spores upon repeated testing. Therefore, classical methods used for the identification of
Saccharomyces
spp. could not be undertaken. Typing by using the restriction fragment length polymorphisms (RFLPs) of the PCR-amplified intergenic transcribed spacer regions (including the 5.8S ribosomal DNA) showed that the three isolates of
S. boulardii
were not separable from authentic isolates of
Saccharomyces cerevisiae
with any of the 10 restriction endonucleases assessed, whereas 9 of the 10 recognized species of
Saccharomyces
could be differentiated. RFLP analysis of cellular DNA with
Eco
RI showed that all three strains of
S. boulardii
had identical patterns and were similar to other authentic
S. cerevisiae
isolates tested. Therefore, the commercial strains of
S. boulardii
available to us cannot be genotypically distinguished from
S. cerevisiae
. Two
S. boulardii
strains were tested in CD-1 and DBA/2N mouse models of systemic disease and showed intermediate virulence compared with virulent and avirulent strains of
S. cerevisiae
. The results of the present study show that these
S. boulardii
strains are asporogenous strains of the species
S. cerevisiae
, not representatives of a distinct and separate species, and possess moderate virulence in murine models of systemic infection. Therefore, caution should be advised in the clinical use of these strains in immunocompromised patients until further study is undertaken.