Search results for "Serotype"
showing 10 items of 130 documents
Identification of a clone of Escherichia coli O103:H2 as a potential agent of hemolytic-uremic syndrome in France
1993
In a French multicenter study, six verocytotoxin-producing Escherichia coli strains were isolated from the stools of 6 of 69 children suffering from hemolytic-uremic syndrome. All strains belonged to serotype O103:H2, a serotype commonly associated with diarrhea in weaned rabbits in France. To determine whether the strains from humans and rabbits were genetically related, they were compared by analyzing their esterase electropherotypes and the restriction fragment length polymorphisms of the ribosomal DNA regions. A common clonal origin of these pathogenic strains was suggested by their identical esterase electropherotypes and their identical ribotypes, in addition to their identical seroty…
DNA Amplification Fingerprinting for Subtyping Neisseria gonorrhoeae Strains
1995
Background and Objectives DNA amplification fingerprinting is used in most epidemiologic studies as a substitute for conventional typing methods. DNA amplification fingerprinting and conventional typing methods were compared in this epidemiologic study of Neisseria gonorrhoeae. Goal of This Study To differentiate 70 Neisseria gonorrhoeae isolates from untreated patients with urogenital gonococcal infection. Study Design Gonococcal strains were characterized by auxo-typing, serotyping, plasmid profile, antibiotic sensitivity, and DNA amplification fingerprinting. The method of unweighted pair-group average linkage was used for cluster analysis. Discriminatory power was calculated applying Si…
Comparison of two PCR methods for detection of Leptospira interrogans in formalin-fixed and paraffin-embedded tissues
2012
In this study we compared two polymerase chain reaction (PCR) methods using either 16S ribosomal RNA (rRNA) or 23S rRNA gene primers for the detection of different Leptospira interrogans serovars. The performance of these two methods was assessed using DNA extracted from bovine tissues previously inoculated with several bacterial suspensions. PCR was performed on the same tissues before and after the formalin-fixed, paraffin-embedding procedure (FFPE tissues). The 23S rDNA PCR detected all fresh and FFPE positive tissues while the 16S rDNA-based protocol detected primarily the positive fresh tissues. Both methods are specific for pathogenic L. interrogans. The 23S-based PCR method successfu…
Epidemiology ofSalmonella typhimurium: ribosomal DNA analysis of strains from human and animal sources
1993
SUMMARYSalmonella typhimuriumis the most frequently identified serovar ofSalmonellain Italy. This serovar is characterized by the widespread dissemination among human and non-human sources of phenotypically and genetically well-differentiated clones.In this study 457 strains ofS. typhimuriumisolated in Italy in the years 1982–91 from human and animal sources were submitted to characterization by the rDNA fingerprinting technique. Application of this typing method, after digestion of chromosomal DNA withHincII endonuclease, confirmed the greatest genetic differentiation of clones ofS. typhimurium, allowing reliable identification of 45 rDNA patterns linked into 9 major clusters. rDNA pattern…
rRNA probing of chromosomal DNA of epidemic and sporadic isolates of Salmonella enterica subsp. Enterica serovar kottbus from Northern and Southern I…
1990
Fifty-two strains of Salmonella enterica subsp. enterica serovar Kottbus, identified at the Centres of Enterobacteriaceae of Northern and Southern Italy, were investigated by molecular genetic methods. Thirteen isolates were recovered during two food-poisoning outbreaks that occurred in May 1987 in Lombardy. The rDNA gene restriction patterns, obtained by probing endonuclease cleaved chromosomal DNA with photobiotin labeled Escherichia coli rRNA, revealed some heterogeneity among strains isolated from Southern Italy, whereas Northern Italy isolates exhibited virtually identical banding patterns.
Multiplex PCR Assay for Detection of Vibrio vulnificus Biotype 2 and Simultaneous Discrimination of Serovar E Strains
2007
ABSTRACT In the present work we develop a multiplex PCR assay for the detection and identification of the fish pathogen Vibrio vulnificus biotype 2 with discriminating potential for zoonotic strains (serovar E). The PCR assay allowed the identification of two new biotype 2 serovar E human isolates from culture collections. Finally, the multiplex was successfully applied to both diagnosis and carrier detection in field samples.
rDNA fingerprinting as a tool in epidemiological analysis of Salmonella typhi infections
1991
SUMMARYCharacterization of 169 strainsof Salmonella typhiof phage types C1, C4, D1and D9isolated in 1975–88 was carried out by rDNA gene restriction pattern analysis. Twenty-four isolates had been recovered during four large waterbone outbreaks in the last 20 years in Sicily; 145 strains, isolated from apparently sporadic cases of infection in Southern Italy in the same period of time, were also examined.Application of rRNA–DNA hybridization technique after digestion of chromosomal DNA withClaI showed the identity of patterns of the epidemic strains of phage types C1and D1, confirming attribution of the outbreaks to single bacterial clones. Patterns of the two available strains of lysotype …
Identification of a novel VP4 genotype carried by a serotype G5 porcine rotavirus strain
2006
AbstractRotavirus genome segment 4, encoding the spike outer capsid VP4 protein, of a porcine rotavirus (PoRV) strain, 134/04-15, identified in Italy was sequenced, and the predicted amino acid (aa) sequence was compared to those of all known VP4 (P) genotypes. The aa sequence of the full-length VP4 protein of the PoRV strain 134/04-15 showed aa identity values ranging from 59.7% (bovine strain KK3, P8[11]) to 86.09% (porcine strain A46, P[13]) with those of the remaining 25 P genotypes. Moreover, aa sequence analysis of the corresponding VP8* trypsin cleavage fragment revealed that the PoRV strain 134/04-15 shared low identity, ranging from 37.52% (bovine strain 993/83, P[17]) to 73.6% (po…
Expression of P, S, and F1C adhesins by cytotoxic necrotizing factor1-producing Escherichia coli from septicemic and diarrheic pigs
1997
Nineteen papC-positive cytotoxic necrotizing factor 1 (CNF1)-producing Escherichia coli isolates from pigs with septicemia or diarrhea were tested for the presence of pap-, sfa-, and afa-related sequences encoding P/Prs, S/F1C, and Dr/AFA adhesins respectively. Production of adhesins by isolates was tested by mannose-resistant hemagglutination (MRHA), sialidase treatment of erythrocytes and particle agglutination tests. Production of P, S, and F1C fimbriae by isolates was also examined by immunofluorescence. All isolates were pap+ by PCR. Eighteen isolates (95%) were MRHA for ovine and human A erythrocytes and exhibited GalNac-GalNac receptor specificity associated with class III P(Prs) adh…
Distribution of VP7 serotypes and VP4 genotypes among rotavirus strains recovered from Italian children with diarrhea
1997
108 rotavirus strains obtained from children with diarrhea hospitalized in Palermo, Italy, in the years 1990-1994, were examined by seminested PCR to study the relative frequency and distribution of the four most common alleles of the gene 4. Such strains were selected from 344 human rotavirus strains recovered in palermo during those years after characterization by electropherotyping, subgrouping and G serotyping. One hundred and seven of the 108 strains could be classified into P types, the P[8], G1 (38.3%) and the P[8], G4 (52.3%) types being predominant. The unique strain whose P genotype could not be identified showed an unusual combination of long migration electrophoretic pattern and…