Search results for "PRIMERS"

Nucleotide variation in the VP7 gene affects PCR genotyping of G9 rotaviruses identified in Italy

2003

A modified (aFT9m) and a degenerate (aFT9d) version of the rotavirus G9-specific primer (aFT9) allowed strains that were previously untypable, because of point mutations accumulating at the primer binding site, to be G typed by reverse transcription-polymerase chain reaction. The strains were collected during 2001-2002 in Italy in hospitals of the Apulia region, from children affected by severe rotavirus-associated enteritis. Using a wide selection of G9 rotaviruses detected worldwide, sequencing of the G9 untypable strains, sequence comparison, and phylogenetic analysis showed that the Italian strains have strong genetic similarity (< or =99.4%) to G9 rotaviruses identified recently in man…

Use of TaqMan® real-time PCR for rapid detection of Salmonella enterica serovar Typhi

2014

We evaluated the performances of a newly designed real-time polymerase chain reaction (PCR) assay using TaqMan® probes to detectSalmonellaTyphi. TaqMan® real-time PCR assays were performed by designed primers and probe based on thestaGgene for detectingS.Typhi. The specificity of the assay was evaluated on 15Salmonellaserovars. The analytical specificity was evaluated on 20 non-Salmonellamicroorganisms. The analytical sensitivity was assessed using decreasing DNA quantities ofS.Typhi ATCC 19430. Finally the detection capability of the TaqMan® real-time PCR assay on isolates recovered from patients withSalmonellainfections was compared to the conventional PCR assay. OnlyS.Typhi strain had po…

Evaluation of a modified single-enzyme amplified fragment length polymorphism (SE-AFLP) technique for subtyping Salmonella enterica serotype Enteriti…

2006

Salmonella enterica subsp. enterica serotype Enteritidis is not readily subtyped beyond the level of phage type (PT). Pulsed field gel electrophoresis (PFGE) is generally acknowledged to be the most discriminating typing method for Salmonella, but only a restricted variety of PFGE types has been described for S. enterica serotype Enteritidis. In the present study, a modification of the SE-AFLP typing method was used to investigate both outbreak and apparently sporadic isolates of S. enterica serotype Enteritidis belonging to different PTs and/or PFGE types. The method proved to be as discriminatory as PFGE when combined with phage typing, and provided subtyping data consistent with epidemio…

MOLECULAR ANALYSIS OF COLLETOTRICHUM SPECIES ASSOCIATED TO OLIVE IN CALABRIA.

2013

A new molecular approach based on the use of genus-specific primers targeting the internal transcribed spacer (ITS) regions of rDNA, was developed and used to study the diversity of Colletotrichum species associated with the olive canopy in the Gioia Tauro plain (Calabria, southern Italy). Representative symptomatic and symptomless samples of leaves, flowers and fruits were collected during 2012 and analyzed by extracting total DNA and amplifying the target region with the genus-specific primers. Amplicons were cloned and sequenced in order to use the ITS as a barcode gene. No Colletotrichum species were detected in the first sampling period (May 28, 2012), whereas around 15% of the analyze…

Metagenomic strategies to assess genetic diversity in Phytophthora species

Two Patients With History of STEC-HUS, Posttransplant Recurrence and Complement Gene Mutations

2013

Hemolytic uremic syndrome (HUS) is a disease of microangiopathic hemolytic anemia, thrombocytopenia and acute renal failure. About 90% of cases are secondary to infections by Escherichia coli strains producing Shiga-like toxins (STEC-HUS), while 10% are associated with mutations in genes encoding proteins of complement system (aHUS). We describe two patients with a clinical history of STEC-HUS, who developed end-stage renal disease (ESRD) soon after disease onset. They received a kidney transplant but lost the graft for HUS recurrence, a complication more commonly observed in aHUS. Before planning a second renal transplantation, the two patients underwent genetic screening for aHUS-associat…

Sequence of the M28 dsRNA: Preprotoxin Is Processed to an α/β Heterodimeric Protein Toxin

1995

The killer and immunity phenotypes of K28 killer strains of Saccharomyces cerevisiae are determined by the 1.75-kb M28 dsRNA virus. In the plus strand, M28p, the K28 preprotoxin gene, comprises bases 13-1047 and is followed, after an additional 85 bases, by a 63-bp poly(A) sequence and a 553-base 3'-sequence. This 3'-sequence contains two potential stem-loop structures predicted to bind the L-A encoded cap-pol protein, initiating encapsidation; high-level expression results in curing of M1 dsRNA. Expression of M28p confers the complete K28 killer and immunity phenotype on a cell lacking M28 dsRNA. K28 toxin is a disulfide-bonded heterodimer of alpha (10.5 kDa) and beta (11 kDa) components w…

Systematic screening for mutations in the human serotonin-2A (5-HT2A) receptor gene: Identification of two naturally occurring receptor variants and …

1996

A statistically significant association between a silent mutation (102T/C) in the serotonin-2A (5-HT2A) receptor gene and schizophrenia has recently been reported in a sample of Japanese patients and healthy controls. This finding suggests that genetic predisposition to schizophrenia may be affected by a functional 5-HT2A receptor variant that is in linkage disequilibrium with 102T/C. In the present study, we have sought to identify genetic variation in the 5-HT2A receptor gene by screening genomic DNA samples from 91 unrelated subjects comprising 45 patients with schizophrenia and 46 healthy controls by using single-strand conformation analysis. We have identified four nucleotide sequence …

Mitochondrial DNA variation and the evolutionary history of cryptic Gammarus fossarum types.

2000

The evolutionary history of the cryptic Gammarus fossarum species complex (Crustacea, Amphipoda) in Central Europe was approached by investigating the genetic variation in populations of a natural contact zone. Nucleotide sequence variation of a 395-bp segment of the mitochondrial 16S rRNA gene was compared to that of six nuclear allozyme loci. Three major mtDNA lineages were found, the eastern clade being consistent with the former allozyme type A. The two western clades (types B and C) were not distinguished previously. Strong sequence divergence and correlation with nuclear genetic isolation in syntopic populations, however, justifies the specific status of the three G. fossarum types. T…

The age and evolution of sociality in Stegodyphus spiders: a molecular phylogenetic perspective

2006

Social, cooperative breeding behaviour is rare in spiders and generally characterized by inbreeding, skewed sex ratios and high rates of colony turnover, processes that when combined may reduce genetic variation and lower individual fitness quickly. On these grounds, social spider species have been suggested to be unstable in evolutionary time, and hence sociality a rare phenomenon in spiders. Based on a partial molecular phylogeny of the genus Stegodyphus , we address the hypothesis that social spiders in this genus are evolutionary transient. We estimate the age of the three social species, test whether they represent an ancestral or derived state and assess diversification relative to s…