Search results for "Real-Time Polymerase Chain Reaction"
showing 10 items of 385 documents
Quantification of Salmonella spp., Listeria monocytogenes and Escherichia coli O157:H7 in non-spiked food products and evaluation of real-time PCR as…
2011
Abstract Escherichia coli O157:H7, Listeria monocytogenes and Salmonella spp. are foodborne pathogens frequently associated with foods such as poultry, ready-to-eat products, fruits and vegetables. PCR-based procedures are rapid, sensitive and accurate; in particular, real-time PCR (qPCR), which besides being an automated high-throughput technique, allows quantification of foodborne pathogens. In the present work, qPCR-based methods were applied for the quantitative detection of E. coli O157:H7, Salmonella spp. and L. monocytogenes in a total of 306 non-spiked food samples in a study carried out in two laboratories simultaneously. qPCR allowed the detection of the three pathogens in around …
Quantitative detection of viable foodborne E. coli O157:H7, Listeria monocytogenes and Salmonella in fresh-cut vegetables combining propidium monoazi…
2012
Abstract The increase of foodborne outbreaks associated with fresh vegetables has highlighted the importance of developing rapid and specific methods for the detection and quantification of foodborne pathogens. In this sense, real-time PCR (qPCR) fulfills these requirements although it may detect dead cells. Recently, a potential strategy to specifically detect viable cells has been proposed relying on the use of DNA binding molecules as sample pretreatment previous to the qPCR. In this study propidium monoazide (PMA) and reagent D, combined with qPCR, were evaluated for the detection and quantification of viable Escherichia coli O157:H7, Salmonella and Listeria monocytogenes. Initially, th…
APPLICATION OF REAL-TIME POLYMERASE CHAIN REACTION FOR RAPID DETERMINATION OFSALMONELLAIN RESTAURANT FOODS
2008
Several foods have been identified as frequently or occasionally contaminated with Salmonella, such as eggs, raw milk and all raw foods of animal origin that may carry salmonella and other bacteria. Salmonellosis is the most common food-borne illness, but it is usually preventable according to the implementation of a food safety system that includes Hazard Analysis and Critical Control Point. In this study, 96 food samples of the University restaurant of Valencia (Spain) were divided into four groups: first course; main course; accompaniment; and dessert, and were analyzed simultaneously with classical and fluorogenic polymerase chain reaction microbiological analysis. Neither of the proced…
A single method for recovery and concentration of enteric viruses and bacteria from fresh-cut vegetables
2011
Fresh-cut vegetables are prone to be contaminated with foodborne pathogens during growth, harvest, transport and further processing and handling. As most of these products are generally eaten raw or mildly treated, there is an increase in the number of outbreaks caused by viruses and bacteria associated with fresh vegetables. Foodborne pathogens are usually present at very low levels and have to be concentrated (i.e. viruses) or enriched (i.e. bacteria) to enhance their detection. With this aim, a rapid concentration method has been developed for the simultaneous recovery of hepatitis A virus (HAV), norovirus (NV), murine norovirus (MNV) as a surrogate for NV, Escherichia coli O157:H7, List…
Silk fibroin scaffolds enhance cell commitment of adult rat cardiac progenitor cells.
2015
The use of three-dimensional (3D) cultures may induce cardiac progenitor cells to synthesize their own extracellular matrix (ECM) and sarcomeric proteins to initiate cardiac differentiation. 3D cultures grown on synthetic scaffolds may favour the implantation and survival of stem cells for cell therapy when pharmacological therapies are not efficient in curing cardiovascular diseases and when organ transplantation remains the only treatment able to rescue the patient’s life. Silk fibroin-based scaffolds may be used to increase cell affinity to biomaterials and may be chemically modified to improve cell adhesion. In the present study, porous, partially orientated and electrospun nanometric n…
Rejuvenative Efficacy and NF-κB Pathway-Dependent Mechanism of Human Platelet Lysate on Skin Aging
2021
Background: Skin aging is an irreversible process associated with poor self-regenerative capability. Human platelet lysate (hPL) contains rich amounts of growth factors, benefiting tissue regeneration. To explore the anti-aging efficacy and mechanism of hPL on skin, this study employed nude mice and human dermal fibroblasts (HDFs) to perform in vitro and in vivo assays. Methods: Flow cytometry and ELISA were conducted for quality control of hPL. In vivo, skin texture grading, histopathological observation, immunofluorescence analysis, and SOD and MDA assays were conducted to determine the effects of hPL on epidermis and dermis of aged skin. In vitro, senescence-associated-beta-galactosidase…
Age-associated telomere shortening in mouse oocytes
2013
Abstract Background Oocytes may undergo two types of aging. The first is induced by exposure to an aged ovarian microenvironment before being ovulated, known as ‘reproductive or maternal aging’, and the second by either a prolonged stay in the oviduct before fertilization or in vitro aging prior to insemination, known as ‘postovulatory aging’. However, the molecular mechanisms underlying these aging processes remain to be elucidated. As telomere shortening in cultured somatic cells triggers replicative senescence, telomere shortening in oocytes during reproductive and postovulatory aging may predict developmental competence. This study aimed to ascertain the mechanisms underlying altered te…
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…
Modulation of MMP-2 and MMP-9 in Churg-Strauss syndrome respiratory mucosa: potential monitoring parameters.
2014
Churg-Strauss (CSS) syndrome is rare and of unknown etiology. It is associated with vasculitis, blood eosinophilia and granulomatosis, and affects multiple organs and systems at various stages of the disease. Specific diagnostic and monitoring tests are not yet available. This study aims to assess the changes in MMP-2 and MMP-9 along with the histopathological alterations in two cases of CSS, as possible potential diagnostic and monitoring criteria. Two adult male patients were diagnosed with CSS in the otorhinolaryngology clinic in the University of Palermo, based on multiple clinical and histopathologic criteria. Biopsies of respiratory mucosa were taken after the consent of the patients…
Single tube real time PCR for detection of Streptococcus pneumoniae, Mycoplasma pneumoniae, Chlamydophila pneumoniae and Legionella pneumophila from …
2012
We designed a multiplex real time PCR for rapid, sensitive and specific detection of Streptococcus pneumoniae, Legionella pneumophila, Chlamydophila pneumoniae and Mycoplasma pneumoniae. The study cases consisted of 129 patients with community acquired pneumonia (CAP). Bacteriological techniques were implemented for detection of the cultivable organisms. DNA were extracted from sputa, throat swabs, bronchoalveolar lavages and tracheal aspirates and used as templates in real time PCR. The primers and probes were designed for cbpA (S. pneumoniae), p1adhesin (M. pneumoniae), mip (L. pneumophila) and ompA (C. pneumoniae). After optimization of real time PCR for every organism, the experiments w…