bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identification of New Verocytotoxin Type 2 Variant B-Subunit Genes in Human and Animal
Escherichia coli
Isolates
Authors: Piérard D. , Muyldermans G. , Moriau L. , Stevens D. , Lauwers S. 
Published: December 2019

ABSTRACT

The sequence of a verocytotoxin 2 (VT2) variant gene that was untypeable by the B subunit PCR and restriction fragment length polymorphism analysis (PCR-RFLP) method described by Tyler et al. (S. D. Tyler, W. M. Johnson, H. Lior, G. Wang, and K. R. Rozee, J. Clin. Microbiol. 29:1339–1343, 1991) was determined and compared with published sequences. It was highly homologous to two recently reported VT2 variant sequences. The PCR-RFLP method described by Tyler et al. was extended to include these new sequences. New VT2 variants were identified in 65 of 359 VT-producing
Escherichia coli
(VTEC) with newly designed primers (VT2-cm and VT2-f) and were characterized as well by restriction analysis of the amplification products obtained with another VT2-specific primer pair (VT2-e and VT2-f). The VT genes harbored by 64 of these isolates proved to be untypeable by Tyler’s PCR-RFLP method because no amplification was obtained with the primers used with this method (VT2-c and VT2-d). The last isolate harbored the new variant gene in addition to VT2vh-a. None of the isolates harboring these new toxin genes belonged to serogroups O157, O26, O103, O111, and O145. All 65 isolates were negative for the
eaeA
gene and were significantly less frequently enterohemolytic or positive for the enterohemorrhagic
E. coli
(EHEC) virulence plasmid than non-O157 VTEC isolates harboring other VT2 genes. They were also less frequently isolated from patients with EHEC-associated symptoms. The extended PCR-RFLP typing method is a useful tool to identify less-virulent VTEC isolates and for VT genotyping in epidemiological studies with non-O157 strains.
Efficacy of API 20C and ID 32C Systems for Identification of Common and Rare Clinical Yeast Isolates
Authors: Ramani Rama , Gromadzki Sally , Pincus David H. , Salkin Ira F. , Chaturvedi Vishnu 
Published: December 2019

ABSTRACT
The abilities of the API 20C and ID 32C yeast identification systems to identify 123 common and 120 rare clinical yeast isolates were compared. API 20C facilitated correct identification of 97% common and 88% rare isolates while ID 32C facilitated correct identification of 92% common and 85% rare isolates.
In Vitro Activities of Ampicillin-Sulbactam and Amoxicillin-Clavulanic Acid against
Acinetobacter baumannii
Authors: Pandey Anita , Kapil Arti , Sood Seema , Goel Vikas , Das Bimal , Seth Pradeep 
Published: December 2019

ABSTRACT

In vitro susceptibility patterns of newer β-lactamase-inhibiting antibiotics ampicillin-sulbactam (A/S) and amoxicillin-clavulanic acid (A/C) for 100 consecutive isolates of
Acinetobacter baumannii
obtained from various clinical samples were studied. The A/C MIC for 86% of the strains was more than 16/8 μg/ml, whereas there was an A/S MIC of more than 16/8 μg/ml for only 38% of the strains. This showed that A/S has significantly superior in vitro activity compared to A/C against
A. baumannii
, although, theoretically, both should have similar activities. The therapeutic superiority of A/S over A/C needs to be studied, or else the breakpoints for these agents in in vitro tests need to be redefined.
Pretreatment with Restriction Enzyme or Bovine Serum Albumin for Effective PCR Amplification of Epstein-Barr Virus DNA in DNA Extracted from Paraffin-Embedded Gastric Carcinoma Tissue
Authors: Satoh Yukio , Takasaka Noriko , Hoshikawa Yoshiko , Osaki Mitsuhiko , Ohfuji Satoshi , Ito Hisao , Kaibara Nobuaki , Kurata Takeshi , Sairenji Takeshi 
Published: December 2019

ABSTRACT

An association between Epstein-Barr virus (EBV) and gastric carcinoma has been studied through the EBV genome present in the carcinoma cells. Recently, we found that EBV DNA in paraffin-embedded gastric carcinoma tissue was detected effectively by PCR after pretreatment of the extracted DNA with a restriction enzyme,
Bam
HI or
Eco
RI. Here, we show that the PCR amplification was also enhanced by pretreatment of the DNA with other restriction enzymes or with bovine serum albumin and several other proteins. Treatment with these proteins may remove a PCR inhibitor(s) in the DNA samples extracted from the paraffin blocks.
Prevalence of Specific Antibodies to
Chlamydia pneumoniae
in Korea
Authors: Choi Tae Yeal , Kim Duck An , Kim Sin Kyung , Kang Jung Oak , Park Sung Soo , Jung Sung Ro 
Published: December 2019

ABSTRACT

To clarify the endemic status of
Chlamydia pneumoniae
in Korea, the incidence of antibodies in 564 serum samples from healthy individuals, patients with respiratory infection, and cord blood specimens was evaluated. We conclude that
C. pneumoniae
infection is highly endemic in Korea and that this infection is associated with acute respiratory diseases.
Identification of Encephalomyocarditis Virus in Clinical Samples by Reverse Transcription-PCR Followed by Genetic Typing Using Sequence Analysis
Authors: Vanderhallen H. , Koenen F. 
Published: December 2019

ABSTRACT
The objective of the present study was to gain a better understanding of the epidemiology of encephalomyocarditis virus (EMCV) infections in pigs by applying molecular techniques. The diagnostic potential of a reverse transcription-PCR (RT-PCR) targeting 286 nucleotides at the 3′ end of the gene which encodes the viral polymerase was assessed with experimental and field samples. In addition, the use of the amplified sequences for an epidemiological study was evaluated. The heart was clearly shown to be the most suitable organ. The detection limit was determined to be 1 viral particle in 100 mg of heart tissue. The sensitivity and specificity of the assay on the basis of the results obtained in this study were 94 and 100%, respectively. Phylogenetic analysis of the amplified sequences classified EMCVs in two distinct lineages. Group A consists of the reference strain ATCC 129B, all isolates collected between 1991 and 1994 in Belgium in association with reproductive failure, and all Greek isolates. All Belgian isolates collected since the first isolation of EMCV in relation to myocardial failure in fatteners in Belgium group together with the isolates from Cyprus (1996 and 1997), Italy (1986 to 1996), and France (1995) in group B irrespective of their pathogenicity. The analyzed part of the 3D gene differed by 13.0% between Groups A and B. In contrast to the sequence homogeneity of the Belgian isolates collected between 1991 and 1994, molecular diversity, which ranged between 0 and 2%, was observed among the Belgian isolates collected in 1995 and 1996. Among all Greek isolates the diversity ranged between 1 and 8%. However, this diversity does not seem to reflect geographical links between the outbreaks. A RT-PCR for the rapid and specific diagnosis of EMCV in a variety of clinical samples followed by nucleotide sequence analysis proved to be valuable for molecular epidemiological studies.
Acquisition and Transmission of the Agent of Human Granulocytic Ehrlichiosis by
Ixodes scapularis
Ticks
Authors: Hodzic Emir , Fish Durland , Maretzki Craig M. , De Silva Aravinda M. , Feng Sunlian , Barthold Stephen W. 
Published: December 2019

ABSTRACT

The purpose of the present study was to investigate the transmission of a human isolate of the agent of human granulocytic ehrlichiosis (HGE agent) from infected mice to larval ticks and to examine the population kinetics of the HGE agent in different stages of the tick life cycle. The HGE agent was quantitated by competitive PCR with blood from infected mice and with
Ixodes scapularis
ticks. The median infectious dose for C3H mice was 10
4
to 10
5
organisms when blood from an infected severe combined immunodeficient mouse was used as an inoculum. Uninfected larval ticks began to acquire infection from infected mice within 24 h of attachment, and the number of HGE agent organisms increased in larval ticks during feeding and after detachment of replete ticks. Molted nymphal ticks, infected as larvae, transmitted infection to mice between 40 and 48 h of attachment. Onset of feeding stimulated replication of the HGE agent within nymphal ticks. These studies suggest that replication of the HGE agent during and after feeding in larvae and during feeding in nymphs is a means by which the HGE agent overcomes inefficiencies in acquisition of infection by ticks and in tick-borne transmission to mammalian hosts.
Rapid Diagnosis of Cholera Caused by
Vibrio cholerae
O139
Authors: Chaicumpa Wanpen , Srimanote Potjanee , Sakolvaree Yuwaporn , Kalampaheti Thareerat , Chongsa-Nguan Manas , Tapchaisri Pramuan , Eampokalap Boonchuay , Moolasart Pikul , Nair G. Balakrish , Echeverria Peter 
Published: December 2019

ABSTRACT

Hybridomas secreting specific monoclonal antibodies (MAbs) to
Vibrio cholerae
serogroup O139 were produced. Six monoclones (hybridomas) secreting MAbs specific only to lipopolysaccharide of
V. cholerae
O139 strains and which did not cross-react to 137 strains of other enteric microorganisms were obtained. These clones were designated 12F5-G11, 12F5-G2, 15F5-H5, 5B9-F8, 14C9-D2, and 6D2-D8. The immunoglobulin (Ig) heavy chain isotypes secreted by these clones were IgG2b, IgG2b, IgG2b, IgM, IgG2b, and IgG3, respectively. Clone 12F5-G11 was selected for mass production of MAb, which was used as a detection reagent in the antigen detection assay for diagnosis of cholera caused by
V. cholerae
O139, and this assay was compared to the conventional bacterial isolation method. Five batches of rectal swab cultures in alkaline-peptone water were collected from 6,497 patients with watery diarrhea. These were 6,310 patients admitted to Bamrasnaradura Infectious Diseases Hospital, 16 patients from Krung Thon Hospital, 78 patients from Bangkok Children’s Hospital, 19 patients from Karen refugee camps, and 74 Indian patients from the National Institute of Cholera and Enteric Diseases, Calcutta, India. The
V. cholerae
O139 isolations from the rectal swab cultures and the antigen detection assays (i.e., the MAb-based dot-blot ELISA) were performed by different persons of different laboratories, and the results were revealed after all specimens had been tested. Of the 6,497 samples tested, the dot-blot ELISA correctly identified 42 of 42
V. cholerae
O139-positive samples and gave a result of positive for three samples which were culture negative for
V. cholerae
O139. The diagnostic sensitivity, specificity, and efficacy of the dot-blot ELISA were 100, 99.95, and 99.26%, respectively. The ELISA is easy to perform and relatively inexpensive. It can test multiple samples at a single time, does not require special equipment, and does not produce great quantities of contaminated waste. Most of all, it reduces the diagnostic time from at least 2 days for the bacterial isolation to less than 90 min. The assay is recommended as a rapid screening test of cholera cases caused by
V. cholerae
O139.
Evaluation of PCR for Detection of DNA Specific for
Aspergillus
Species in Sera of Patients with Various Forms of Pulmonary Aspergillosis
Authors: Yamakami Yuriko , Hashimoto Atsuro , Yamagata Eiji , Kamberi Perparim , Karashima Reiko , Nagai Hiroyuki , Nasu Masaru 
Published: December 2019

ABSTRACT

Pulmonary aspergillosis is classified into invasive, saprophytic, and allergic forms. In this study, we evaluated the usefulness of PCR for differentiating between different forms of aspergillosis or in monitoring disease activity during treatment by detecting DNA specific for
Aspergillus
species in the serum. Nested PCR was used to detect
Aspergillus
DNA in the sera of 30 patients with various forms of pulmonary aspergillosis. The results were compared with those of latex agglutination tests for detecting galactomannan antigen. We also examined the serial changes in the results of nested PCR during and after treatment of a subgroup of patients with invasive pulmonary aspergillosis with amphotericin B. The highest proportion of positive nested PCR results were in patients with invasive aspergillosis (10 of 12; 83%), while patients with pulmonary aspergilloma had the lowest frequency of positive tests (1 of 9; 11%). These results suggested that the sensitivity of the nested PCR depends on the extent of invasion by
Aspergillus
species. Serial assays showed that the results of nested PCR became negative shortly after commencement of antifungal treatment and that such changes did not correlate with clinical responsiveness to treatment. Our results indicate the potential usefulness of nested PCR with serum samples for the diagnosis of invasive aspergillosis and the detection of a shift in the status of infection from a noninvasive type to invasive aspergillosis. However, the results of the nested PCR did not correlate with the response to antifungal treatment.
Critical Evaluation of 4-Week Incubation for Fungal Cultures: Is the Fourth Week Useful?
Authors: Labarca Jaime A. , Wagar Elizabeth A. , Grasmick Ann E. , Kokkinos Heidi M. , Bruckner David A. 
Published: December 2019

ABSTRACT
To determine the benefit of a 4-week incubation for mycology cultures, we evaluated all positive cultures during the fourth week of incubation in a 1-year period. Of 3,855 positive mycology cultures (yeast, 82%; molds, 18%), 62 (1.6%) were positive during the fourth week (yeast, 42%; molds, 58%). Only 15 of the 62 cultures (24%) were considered clinically relevant (2 isolates from invasive fungal infection and 13 isolates from cutaneous mycosis). With the exception of those from skin samples, isolates recovered during the fourth week are rarely important for patient care.
Prevalence of Astrovirus Infection among Chilean Children with Acute Gastroenteritis
Authors: Gaggero Aldo , O’Ryan Miguel , Noel Jacqueline S. , Glass Roger I. , Monroe Stephan S. , Mamani Nora , Prado Valeria , Avendaño Luis F. 
Published: December 2019

ABSTRACT
The frequency of astrovirus infection in 456 Chilean children with diarrhea was determined by enzyme-linked immunosorbent assay, reverse transcriptase PCR, and cell culture. Astrovirus was detected in 16.5% of rotavirus-negative and 7% of rotavirus-positive samples obtained from emergency rooms or hospitals and in 11% of samples from day care centers. HAst-1 was the predominant serotype identified.
Differentiation of
Corynebacterium amycolatum
,
C. minutissimum
, and
C. striatum
by Carbon Substrate Assimilation Tests
Authors: Renaud François N. R. , Dutaur Marianne , Daoud Salah , Aubel Dominique , Riegel Philippe , Monget Daniel , Freney Jean 
Published: December 2019

ABSTRACT

We tested the carbon substrate assimilation patterns of 40
Corynebacterium amycolatum
strains, 19
C. minutissimum
strains, 50
C. striatum
strains, and 1
C. xerosis
strain with the Biotype 100 system (bioMérieux, Marcy-l’Étoile, France). Twelve carbon substrates of 99 allowed discrimination among the species tested. Additionally, assimilation of 3 of these 12 carbon substrates (maltose, N -acetyl-
d
-glucosamine, and phenylacetate) was tested with the API 20 NE identification system (bioMérieux). Since concordant results were observed with the two systems for these three carbon substrates, either identification system can be used as a supplementary tool to achieve phenotypic differential identification of
C. amycolatum
,
C. minutissimum
, and
C. striatum
in the clinical microbiology laboratory.
Toxoplasma gondii
-Associated Guillain-Barré Syndrome in an Immunocompetent Patient
Authors: Bossi Philippe , Caumes Eric , Paris Luc , Dardé Marie-Laure , Bricaire François 
Published: December 2019

ABSTRACT
We report a case of Guillain-Barré syndrome associated with an acute, disseminated toxoplasmosis due to a new and unknown zymodeme (zymodeme 12) in an immunocompetent patient. The patient’s condition improved with pyrimethamine and sulfadiazine. Only the standard treatment for toxoplasmosis was effective, whereas intravenous immunoglobulins were ineffective.
Survival of Vancomycin-Resistant and Vancomycin-Susceptible Enterococci on Dry Surfaces
Authors: Wendt Constanze , Wiesenthal Bettina , Dietz Ekkehart , Rüden Henning 
Published: December 2019

ABSTRACT

We compared the abilities of
Enterococcus faecium
strains (three vancomycin-resistant enterococci [VRE] and five vancomycin-susceptible enterococci [VSE]) and
Enterococcus faecalis
strains (one VRE and 10 VSE) to survive under dry conditions. Bacterial suspensions of the strains were inoculated onto polyvinyl chloride and stored under defined conditions for up to 16 weeks. All strains survived for at least 1 week, and two strains survived for 4 months. A statistical model was used to distribute the 19 resulting survival curves between two types of survival curves. The type of survival curve was not associated with the species (
E. faecalis
versus
E. faecium
), the source of isolation (patient versus environment), or the susceptibility to vancomycin (VRE versus VSE). Resistance to dry conditions may promote the transmissibility of a strain, but VRE have no advantages over VSE with respect to their ability to survive under dry conditions.
Serotyping Scheme for
Campylobacter jejuni
and
Campylobacter coli
Based on Direct Agglutination of Heat-Stable Antigens
Authors: Frost J. A. , Oza A. N. , Thwaites R. T. , Rowe B. 
Published: December 2019

ABSTRACT

Campylobacter is now the most frequently reported cause of gastrointestinal disease in England and Wales, yet few isolates are characterized beyond the genus level. The majority of isolates are
Campylobacter jejuni
(90%), with most of the remainder being
Campylobacter coli
. We describe an adaptation of the Penner serotyping scheme in which passive hemagglutination has been replaced by detection of heat-stable antigens by direct bacterial agglutination; absorbed antisera are used where appropriate. This scheme has been used to type 2,407
C. jejuni
samples and 182
C. coli
samples isolated in Wales between April 1996 and March 1997. Forty-seven
C. jejuni
serotypes were identified, with the 10 most prevalent serotypes accounting for 53% of the isolates tested; 19% of the isolates were untypeable. Only fifteen
C. coli
serotypes were identified, with three serotypes accounting for 69% of the isolates. This scheme provides a baseline for epidemiological studies of
C. jejuni
and
C. coli.
Improved Diagnostic PCR Assay forActinobacillus pleuropneumoniaeBased on the Nucleotide Sequence of an Outer Membrane Lipoprotein
Authors: Gram Trine , Ahrens Peter 
Published: December 2019

ABSTRACTThe gene (omlA) coding for an outer membrane protein ofActinobacillus pleuropneumoniaeserotypes 1 and 5 has been described earlier and has formed the basis for development of a specific PCR assay. The corresponding regions of all 12A. pleuropneumoniaereference strains of biovar 1 were sequenced. Alignment of the sequences revealed conserved terminal and variable middle regions, which divided the reference strains into four distinct groups. Primers were selected from the conserved 5′ and 3′ termini of the gene. A 950-bp amplicon was obtained from each of 102 tested field isolates ofA. pleuropneumoniaeobtained from lungs. Their identity was verified by sequencing approximately 500 bp of the amplification product from 50 of theA. pleuropneumoniaeisolates, which all showed the expected DNA sequence characteristic of the serotype. To test the specificity of the reaction, 23 other bacterial species related toA. pleuropneumoniaeor isolated from pigs were assayed. They were all found negative in the PCR, as were tonsil cultures from 50 pigs of anA. pleuropneumoniae-negative herd. The sensitivity assessed by agarose gel analysis of the PCR product was 102CFU/PCR test tube. The specificity and sensitivity of this PCR compared to those of culture suggest the use of this PCR for routine identification ofA. pleuropneumoniae.
Association of Deficiency in Antibody Response to Vaccine and Heterogeneity ofEhrlichia risticiiStrains with Potomac Horse Fever Vaccine Failure in Horses
Authors: Dutta Sukanta K. , Vemulapalli Ramesh , Biswas Biswajit 
Published: December 2019

ABSTRACTEhrlichia risticiiis the causative agent of Potomac horse fever (PHF), which continues to be an important disease of horses. Commercial inactivated whole-cell vaccines are regularly used for immunization of horses against the disease. However, PHF is occurring in large numbers of horses in spite of vaccination. In a limited study, 43 confirmed cases of PHF occurred between the 1994 and 1996 seasons; of these, 38 (89%) were in horses that had been vaccinated for the respective season, thereby clearly indicating vaccine failure. A field study of horses vaccinated with two PHF vaccines indicated a poor antibody response, as determined by immunofluorescence assay (IFA) titers. In a majority of horses, the final antibody titer ranged between 40 and 1,280, in spite of repeated vaccinations. None of the vaccinated horses developed in vitro neutralizing antibody in their sera. Similarly, one horse experimentally vaccinated three times with one of the vaccines showed a poor antibody response, with final IFA titers between 80 and 160. The horse did not develop in vitro neutralizing antibody or antibody against the 50/85-kDa strain-specific antigen (SSA), which is the protective antigen of the original strain, 25-D, and the variant strain of our laboratory, strain 90-12. Upon challenge infection with the 90-12 strain, the horse showed clinical signs of the disease. The horse developed neutralizing antibody and antibody to the 50/85-kDa SSA following the infection. Studies of the newE. risticiiisolates from the field cases indicated that they were heterogeneous among themselves and showed differences from the 25-D and 90-12 strains as determined by IFA reactivity pattern, DNA amplification finger printing profile, and in vitro neutralization activity. Most importantly, the molecular sizes of the SSA of these isolates varied, ranging from 48 to 85 kDa. These studies suggest that the deficiency in the antibody response to the PHF vaccines and the heterogeneity ofE. risticiiisolates may be associated with the vaccine failure.
Antibody Tests for Identification of
Mycobacterium bovis
-Infected Bovine Herds
Authors: Amadori M. , Tameni S. , Scaccaglia P. , Cavirani S. , Archetti I. L. , Giandomenico R. Quondam 
Published: December 2019

ABSTRACT
Antibody in sera from 560 cattle of tuberculosis (TB)-infected and TB-free herds was investigated by competition and indirect enzyme-linked immunosorbent assays using bovine purified protein derivative tuberculin as the antigen. Antibody was detected in sera from both types of herd, with a widely overlapping range of titers. However, a “tail” of high-titered sera was observed for the distribution of data for only those cattle from TB-infected herds.
DNA Fingerprinting of
Mycobacterium tuberculosis
Complex Culture Isolates Collected in Brazil and Spotted onto Filter Paper
Authors: Burger Marion , Raskin Salmo , Brockelt Sonia R. , Amthor Beate , Geiss Heinrich K. , Haas Walter H. 
Published: December 2019

ABSTRACT

The usefulness of filter paper for preservation of bacterial cells was shown by mixed-linker DNA fingerprint analysis of
Mycobacterium tuberculosis
isolates from 77 Brazilian patients. DNA fingerprints of samples spotted onto filter paper and conventional culture material were identical. Thus, filter paper specimens analyzed by an amplification-based typing method provide a new resource for epidemiological studies of infectious diseases.