bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prevalence of
Shigella
Enterotoxins 1 and 2 among
Shigella
Strains Isolated from Patients with Traveler's Diarrhea
Authors: Vargas Martha , Gascon Joaquim , De Anta Maria Teresa Jimenez , Vila Jordi 
Published: December 2019

ABSTRACT

Shigella
spp. are known primarily as a cause of bacillary dysentery. However, in an initial phase, numerous patients exhibit watery diarrhea that may or may not be followed by dysentery. New virulence factors associated with the species of
Shigella
have recently been described. These are enterotoxins 1 and 2 of
Shigella
(ShET-1 and ShET-2, respectively). The aim of the present study was to determine the prevalence of ShET-1 and ShET-2 in species of
Shigella
isolated from patients with traveler's diarrhea. During the period from 1993 to 1998, stool samples from 500 travelers with diarrhea were cultured for the isolation of
Shigella
spp. and other enteropathogens. The detection of ShET-1 and ShET-2 was performed by a PCR technique with specific primers. Among a total of 51 strains of
Shigella
isolated during this period (22
S. flexneri
, 26
S. sonnei
, and 3
S. dysenteriae
strains), at least one enterotoxin was detected in 31 (60.78%) strains; 2 (9.09%; both of which were
S. flexneri
strains) produced only ShET-1, while 21 (41.17%; 3
S. flexneri
, 15
S. sonnei
, and 3
S. dysenteriae
strains) produced ShET-2. Furthermore, 8 (15.69%) of 22
S. flexneri
strains presented both enterotoxins. Our results show that the prevalence of ShET-2 was high in all the
Shigella
species studied and confirm that ShET-1 is detected only in
S. flexneri.
Bartonella vinsoniisubsp.berkhoffiiand Related Members of the Alpha Subdivision of theProteobacteriain Dogs with Cardiac Arrhythmias, Endocarditis, or Myocarditis
Authors: Breitschwerdt Edward B. , Atkins Clarke E. , Brown Talmage T. , Kordick Dorsey L. , Snyder Patti S. 
Published: December 2019

ABSTRACTCardiac arrhythmias, endocarditis, or myocarditis was identified in 12 dogs, of which 11 were seroreactive toBartonella vinsoniisubspeciesberkhoffiiantigens. Historical abnormalities were highly variable but frequently included substantial weight loss, syncope, collapse, or sudden death. Fever was an infrequently detected abnormality. Cardiac disease was diagnosed following an illness of short duration in most dogs, but a protracted illness of at least 6 months' duration was reported for four dogs. Valvular endocarditis was diagnosed echocardiographically or histologically in eight dogs, two of which also had moderate to severe multifocal myocarditis. Four dogs lacking definitive evidence of endocarditis were included because of seroreactivity toB. vinsoniiantigens and uncharacterized heart murmurs and/or arrhythmias. Alpha proteobacteria were not isolated from the blood by either conventional or lysis centrifugation blood culture techniques. Using PCR amplification and DNA sequencing of a portion of the 16S rRNA gene,B. vinsoniiwas identified in the blood or heart valves of three dogs. DNA sequence alignment of PCR amplicons derived from blood or tissue samples from seven dogs clustered among members of the alpha subdivision of theProteobacteriaand suggested the possibility of involvement of one or more alpha proteobacteria; however, because of the limited quantity of sequence, the genus could not be identified. Serologic or molecular evidence of coinfection with tick-transmitted pathogens, includingEhrlichia canis,Babesia canis,Babesia gibsonii, or spotted fever group rickettsiae, was obtained for seven dogs. We conclude thatB. vinsoniisubsp.berkhoffiiand closely related species of alpha proteobacteria are an important, previously unrecognized cause of arrhythmias, endocarditis, myocarditis, syncope, and sudden death in dogs.
Genotypic and Phenotypic Characterization of “
Streptococcus milleri
” Group Isolates from a Veterans Administration Hospital Population
Authors: Clarridge Jill E. , Osting Cheryl , Jalali Mehri , Osborne Janet , Waddington Michael 
Published: December 2019

ABSTRACT

Because identification of the species within the “Streptococcus milleri” group is difficult for the clinical laboratory as the species share overlapping phenotypic characteristics, we wished to confirm biochemical identification with identification by 16S rRNA gene sequence analysis. Ninety-four clinical isolates previously identified as the “Streptococcus milleri” group were reclassified as
S. anginosus
,
S. constellatus
, or
S. intermedius
with the API 20 Strep system (bioMerieux Vikek, Hazelton, Mo.) and the Fluo-card (Key Scientific, Round Rock, Tex.). In addition, we determined the Lancefield group, hemolysis, colony size, colony texture, repetitive extragenic palindromic PCR (rep-PCR) pattern, and cellular fatty acid (CFA) profile (MIDI, Newark, Del.). 16S rRNA gene sequence analysis with 40 selected representative strains showed three distinct groups, with
S. constellatus
and
S. intermedius
found to be more closely related to each other than to
S. anginosus
, and further distinguished a biochemically distinct group of urogenital isolates within the
S. anginosus
group of isolates. Except for strains unreactive with the Fluo-card (8%), all
S. anginosus
and
S. intermedius
strains identified by sequencing were similarly identified by biochemical testing. However, 23% of the selected
S. constellatus
isolates identified by sequencing (9% of all
S. constellatus
isolates) would have been identified as
S. anginosus
or
S. intermedius
by biochemical tests. Although most
S. anginosus
strains formed one unique cluster by CFA analysis and most
S. constellatus
strains showed similar rep-PCR patterns, neither method was sufficiently dependable for identification. Whereas Lancefield group or lactose fermentation did not correspond to sequence or biochemical type,
S. constellatus
was most likely to be beta-hemolytic and
S. intermedius
was most likely to have a dry colony type. The most frequent isolate in our population was
S. constellatus
, followed by
S. anginosus
. There was an association of
S. anginosus
with a gastrointestinal or urogenital source, and there was an association of
S. constellatus
and
S. intermedius
with both the respiratory tract and upper-body abscesses.
Importance of Selective Media for Recovery of Yeasts from Clinical Specimens
Authors: Sandven Per , Lassen Jørgen 
Published: December 2019

ABSTRACT
We compared the recovery of yeasts from clinical specimens cultured on routine bacteriological media to the recovery of yeast from specimens cultured on a selective fungal medium (Sabouraud agar). The use of Sabouraud agar was especially important in cases of mixed cultures, since in such cases yeast was recovered on bacteriological media from only 50% of 44 yeast-positive pus specimens and from 22.5% of 22 yeast-positive throat specimens. The use of a selective fungal medium is therefore necessary to ensure the detection of yeast in specimens containing a mixture of bacteria and yeasts. As a result, clinicians must request yeast isolation when clinically indicated, and the microbiological laboratory must add a selective fungal medium when clinically significant yeasts are likely to be encountered. It is also important that selective fungal media be used in clinical studies of yeast infections.
Evaluation of a New Commercially Available Immunoglobulin M Capture Enzyme-Linked Immunosorbent Assay for Diagnosis of Japanese Encephalitis Infections
Authors: Cuzzubbo Andrea J. , Endy Timothy P. , Vaughn David W. , Solomon Tom , Nisalak Ananda , Kalayanarooj Siripen , Dung Nguyen Minh , Warrilow David , Aaskov John , Devine Peter L. 
Published: December 2019

ABSTRACT
A new commercial enzyme-linked immunosorbent assay (ELISA) for the diagnosis of Japanese encephalitis virus infections showed a sensitivity of 88% with sera and 81% with cerebrospinal fluid and a specificity of 97% with sera from patients with primary and secondary dengue virus infections. Specificity was 100% when samples from nonflavivirus infections were tested.
Cloning and Characterization of a Nonhemolytic Phospholipase C Gene from
Burkholderia pseudomallei
Authors: Korbsrisate Sunee , Suwanasai Nuttiga , Leelaporn Amornrut , Ezaki Takayuki , Kawamura Yoshiaki , Sarasombath Suttipant 
Published: December 2019

ABSTRACT

We cloned and characterized a phosphatidylcholine-hydrolyzing phospholipase C (PC-PLC) gene from
Burkholderia pseudomallei
. DNA sequence analysis of the gene indicated an open reading frame coding for 700 amino acids with a 34-amino-acid signal peptide. When cleaved, this yields a secreted 73-kDa mature protein. The deduced amino acid sequence exhibited 48% similarity to that of a nonhemolytic PLC from
Pseudomonas aeruginosa
. The expressed PC-PLC was heat stable, nonhemolytic for sheep erythrocytes, and active between pH 2 and 8. Western blot analysis with sera from melioidosis patients indicated that they produced immunoglobulin M antibodies against this PC-PLC protein.
Viability of
Trichomonas vaginalis
in Transport Medium
Authors: Beverly A. L. , Venglarik M. , Cotton B. , Schwebke J. R. 
Published: December 2019

ABSTRACT

The ability of Amies gel agar transport medium to maintain the viability of
Trichomonas vaginalis
was determined by comparing transported vaginal specimens to specimens immediately inoculated into culture medium. The prevalence of trichomonosis in the study population was 26% (68 of 260 women). The immediate inoculation method detected infections in 64 of 68 infected women (sensitivity of 94.1%). The transport method detected 62 of 68 infections (sensitivity of 91.2%). There was no significant difference between the two methods.
Recovery of Mycobacteria from Patients with Cystic Fibrosis
Authors: Bange Franz-Christoph , Kirschner Philip , Böttger Eric C. 
Published: December 2019

ABSTRACT

Despite decontamination, overgrowth by pseudomonads renders cultural isolation of mycobacteria from respiratory specimens of patients with cystic fibrosis (CF) difficult or impossible. We performed a prospective study by comparing levels of reduction of overgrowth and recovery of mycobacteria using either pretreatment with
N
-acetyl-
l
-cysteine (NALC)–NaOH alone or pretreatment with NALC-NaOH and then with oxalic acid. From 406 specimens of 148 CF patients, 11 specimens were positive for mycobacteria, 5 of which grew mycobacteria after decontamination by either procedure. Three specimens grew mycobacteria only after decontamination with NALC-NaOH, whereas three specimens grew mycobacteria only after treatment with NALC-NaOH followed by oxalic acid but were overgrown after decontamination with NALC-NaOH. Thus, inactivation of mycobacteria by the more aggressive oxalic acid treatment offsets its beneficial effect of reducing the proportion of cultures overgrown with microorganisms other than mycobacteria.
Transport and Storage of Fresh and Frozen Gastric Biopsy Specimens for Optimal Recovery of
Helicobacter pylori
Authors: Heep Markus , Scheibl Karl , Degrell Andrea , Lehn Norbert 
Published: December 2019

ABSTRACT

The viability of
Helicobacter pylori
in vitro and in gastric biopsy specimens was determined. Recovery rates were 94, 87, and 77% from biopsy specimens in Portagerm pylori in cooled containers after 1, 2, and 3 days of transport, respectively (
n
= 307), and 97% if stored and shipped in glycerol broth at −70°C (
n
= 232).
PCR Assay for Detecting Porcine Cytomegalovirus
Authors: Hamel Andre L. , Lin Lihua , Sachvie Cheryl , Grudeski Elsie , Nayar Gopi P. S. 
Published: December 2019

ABSTRACT
This is the first published report of a PCR assay for detecting porcine cytomegalovirus (PCMV), the causative agent of inclusion body rhinitis in pigs. The DNA to be tested was extracted directly from lungs and nasal scrapings of pigs with various clinical syndromes. Fifty-nine percent (74 of 126) of tested pigs with various clinical syndromes were found to be PCR positive for PCMV. It is hoped that veterinary diagnostic laboratories will benefit by using this PCR assay for routine testing and surveillance of PCMV in pigs.
Development of a Universal Intimin Antiserum and PCR Primers
Authors: Batchelor Miranda , Knutton Stuart , Caprioli Alfredo , Huter Veronika , Zanial Mazlina , Dougan Gordon , Frankel Gad 
Published: December 2019

ABSTRACT

Enteropathogenic
Escherichia coli
(EPEC) and enterohemorrhagic
E. coli
(EHEC) constitute a significant risk to human health worldwide. A hallmark of both pathogens is their ability to produce characteristic attaching-and-effacing (A/E) lesions in intestinal epithelial cells. Genes encoding A/E lesion formation map to a chromosomal pathogenicity island termed the locus of enterocyte effacement (LEE). Intimin, an LEE-encoded bacterial adhesion molecule, mediates the intimate bacterium-host cell interaction characteristic of A/E lesions. On the basis of characterization of the C-terminal 280-amino-acid cell binding domain of intimin (Int280
661–939
), four distinct Int280 types (types α, β, γ, and δ) have been identified. Importantly, Int280α and Int280β antisera specifically recognized their respective intimin types. Using a conserved region of the intimin molecule (Int
388–667
) and primers synthesized to generate the recombinant Int
388–667
, we have now generated universal intimin antiserum and PCR primers that are reactive with the different intimin types expressed by both human and animal A/E lesion-forming strains. Use of immunogold electron microscopy to visualize intimin on the surfaces of EPEC and EHEC strains revealed, in general, a uniform distribution on the bacterial cell surface. However, a filamentous staining pattern was observed with a few strains expressing intimin γ. Cloning of the intimin
eae
gene from one such strain (strain ICC57) into strain CVD206, an EPEC strain which harbors a null deletion in
eae
, produced a uniform intimin staining pattern indicating that, if the filamentous staining pattern defines a filamentous form of intimin γ, it is dependent upon the genetic background of the strain and is not a feature of the intimin molecule.
Species and Genotypic Diversities and Similarities of Pathogenic Yeasts Colonizing Women
Authors: Xu Jianping , Boyd Cynthia M. , Livingston Elizabeth , Meyer Wieland , Madden John F. , Mitchell Thomas G. 
Published: December 2019

ABSTRACT

We examined the patterns of strain relatedness among pathogenic yeasts from within and among groups of women to determine whether there were significant associations between genotype and host condition or body site. A total of 80 yeast strains were isolated, identified, and genotyped from 49 female volunteers, who were placed in three groups: (i) 19 women with AIDS, (ii) 11 pregnant women without human immunodeficiency virus (HIV) infection, and (iii) 19 women who were neither pregnant nor infected with HIV. Seven yeast species were recovered, including 59 isolates of
Candida albicans
, 9 isolates of
Candida parapsilosis
, 5 isolates of
Candida krusei
, 3 isolates of
Candida glabrata
, 2 isolates of
Saccharomyces cerevisiae
, and 1 isolate each of
Candida tropicalis
and
Candida lusitaniae
. Seventy unique genotypes were identified by PCR fingerprinting with the M13 core sequence and by random amplified polymorphic DNA analysis. Of the nine shared genotypes, isolates from three different hosts were of one genotype and pairs of strains from different body sites of the same host shared each of the other eight genotypes. Genetic similarities among groups of strains were calculated and compared. We found no significant difference in the patterns of relatedness of strains from the three body sites (oral cavity, vagina, and rectum), regardless of host conditions. The yeast microflora of all three host groups had similar species and genotypic diversities. Furthermore, a single host can be colonized with multiple species or multiple genotypes of the same species at the same or different body sites, indicating dynamic processes of yeast colonization on women.
Bacteriological and Molecular Analysis of Rifampin-Resistant
Mycobacterium tuberculosis
Strains Isolated in Australia
Authors: Yuen Lilly K. W. , Leslie David , Coloe Peter J. 
Published: December 2019

ABSTRACT

To develop a better understanding of the epidemiology and molecular biology of rifampin-resistant
Mycobacterium tuberculosis
strains in Australia, 50 clinical isolates (33 rifampin-resistant and 17 rifampin-sensitive strains) cultured between 1990 and 1997 were analyzed by a number of bacteriological and molecular techniques. Examination of the drug resistance profiles of the 33 rifampin-resistant isolates revealed that 91% were resistant to rifampin in combination with resistance to isoniazid, 88% were resistant to rifampin on first isolation, and 81% showed cross-resistance with rifabutin. On the basis of the demographic data provided for the patients infected with the rifampin-resistant strains, 90% of the patients were born overseas. Of these patients, 64% developed clinical symptoms within 5 years of residence in Australia. On a molecular level, analysis of the
rpoB
gene revealed that 97% of the rifampin-resistant isolates had missense mutations within a conserved region of the gene, and eight types of missense mutations were detected. Of the 31 rifampin-resistant isolates that were typed by restriction fragment length polymorphism (RFLP) analysis, 28 distinct patterns were obtained by RFLP analysis with IS
6110
, and three clusters of genetically related isolates were identified. All isolates within the clusters were from patients who were born overseas and who had the same country of origin. The results from this study provide an overview of the current situation of rifampin resistance in Australia and can serve as a basis for continued monitoring of drug-resistant
M. tuberculosis
strains isolated within the country.
Epidemiology of OropharyngealCandidaColonization and Infection in Patients Receiving Radiation for Head and Neck Cancer
Authors: Redding Spencer W. , Zellars Richard C. , Kirkpatrick William R. , McAtee Robert K. , Caceres Marta A. , Fothergill Annette W. , Lopez-Ribot Jose L. , Bailey Cliff W. , Rinaldi Michael G. , Patterson Thomas F. 
Published: December 2019

ABSTRACTOral mucosal colonization and infection withCandidaare common in patients receiving radiation therapy for head and neck cancer. Infection is marked by oral pain and/or burning and can lead to significant patient morbidity. The purpose of this study was to identifyCandidastrain diversity in this population by using a chromogenic medium, subculturing, molecular typing, and antifungal susceptibility testing of clinical isolates. These results were then correlated with clinical outcome in patients treated with fluconazole for infection. Specimens from 30 patients receiving radiation therapy for head and neck cancer were cultured weekly forCandida. Patients exhibiting clinical infection were treated with oral fluconazole. All isolates were plated on CHROMagar Candida and RPMI medium, subcultured, and submitted for antifungal susceptibility testing and molecular typing. Infections occurred in 27% of the patients and were predominantly due toCandida albicans(78%).Candidacarriage occurred in 73% of patients and at 51% of patient visits. Yeasts other thanC. albicanspredominated in carriage, as they were isolated from 59% of patients and at 52% of patient visits. All infections responded clinically, and all isolates were susceptible to fluconazole. Molecular typing showed that most patients had similar strains throughout their radiation treatment. One patient, however, did show the acquisition of a new strain. With this high rate of infection (27%), prophylaxis to prevent infection should be evaluated for these patients.
Molecular Epidemiology and Genetic Diversity of Echovirus Type 30 (E30): Genotypes Correlate with Temporal Dynamics of E30 Isolation
Authors: Oberste M. Steven , Maher Kaija , Kennett Margery L. , Campbell Janice J. , Carpenter Michael S. , Schnurr David , Pallansch Mark A. 
Published: December 2019

ABSTRACT

Echovirus type 30 (E30) (genus,
Enterovirus
; family,
Picornaviridae
) has caused large outbreaks of aseptic meningitis in many regions of the world in the last 40 years. U.S. enterovirus surveillance data for the period 1961 to 1998 indicated that the annual proportion of E30 isolations relative to total enterovirus isolations has fluctuated widely, from a low of 0% in 1966 to a high of 42% in 1998. Peaks of E30 isolations occurred in the years 1968 to 1969, 1981 to 1984, 1990 to 1993, and 1997 to 1998, coincident with large nationwide outbreaks of E30-associated aseptic meningitis. Analysis of the complete VP1 sequence (876 nucleotides) of 136 E30 strains isolated in geographically dispersed regions of the United States and nine other countries between 1956 and 1998 indicated that the currently circulating E30 strains are genetically distinct from those isolated 30 to 40 years ago. Phylogenetic reconstruction demonstrated the existence of at least four distinct genetic groups, three of which have not been isolated in North America since 1981. Two of the three groups disappeared during periods when E30 was isolated infrequently. All North American E30 strains isolated after 1988 were closely related to one another, and all post-1993 isolates were of the same lineage within this group. Surveillance data indicate that E30 causes large national outbreaks of 2- to 4-year durations, separated by periods of relative quiescence. Our results show that shifts in the overall genetic diversity of E30 and the predominant genetic type correlate temporally with the dynamics of E30 isolation. The sequence data also provide a basis for the application of molecular techniques for future epidemiologic investigations of E30 disease.
vanA
and
vanB
Incorporate into an Endemic Ampicillin-Resistant Vancomycin-Sensitive
Enterococcus faecium
Strain: Effect on Interpretation of Clonality
Authors: Suppola Juhana P. , Kolho Elina , Salmenlinna Saara , Tarkka Eveliina , Vuopio-Varkila Jaana , Vaara Martti 
Published: December 2019

ABSTRACT

Clonal spread and horizontal transfer in the spread of vancomycin resistance genes were investigated. Multiplex PCR, pulsed-field gel electrophoresis (PFGE), hybridization of enterococcal plasmids with the
vanA
and
vanB
probes, and sequencing of a fragment of
vanB
were used in the analysis. Before May 1996, 12 vancomycin-resistant
Enterococcus faecium
(VRE) isolates were found in Finland. Between May 1996 and October 1997, 156 VRE isolates were found in the Helsinki area. Between December 1997 and April 1998, fecal samples from 359 patients were cultured for VRE. One new case of colonization with VRE was found. During the outbreak period, 88% (137 of 155) of the VRE isolates belonged to two strains (VRE types I and II), as determined by PFGE. Each VRE type I isolate possessed
vanB
, and five isolates also had
vanA
. Of the 34 VRE type II isolates, 27 possessed
vanA
and 7 possessed
vanB
. Fifteen of 21 (71%) ampicillin-resistant, vancomycin-sensitive
E. faecium
(VSE) isolates found during and after the outbreak period in one ward were also of type II. Two VSE type II isolates were found in the hospital before the outbreak in 1995. By PFGE, the three groups (
vanA
,
vanB
, or no
van
gene) of type II shared the same band differences with the main type of VRE type II with
vanA
. None of the differences was specific to or determinative for any of the groups. Our material suggests that
vanA
and
vanB
incorporate into an endemic ampicillin-resistant VSE strain.