Listeriolysin is a virulence factor that appears to be necessary for the intracellular survival of Listeria monocytogenes. As shown in this investigation, listeriolysin is produced in only small amounts by clinical isolates of L. monocytogenes belonging to the serogroup 1/2a, but its synthesis can be induced by heat shock and to a lesser extent by oxidative stress. In addition to about 15 heat ...

Listeria monocytogenes, isolated from outbreaks in either human or nonhuman primate populations, was administered orally at doses ranging from 10(6) to 10(10) CFU. Four of 10 treated animals delivered stillborn infants. L. monocytogenes was isolated from fetal tissue, and the pathology was consistent with L. monocytogenes infection as the cause of pregnancy loss. For all pregnancies resulting i...

background the genus-listeria has two pathogenic species namely, listeria monocytogenes and listeria ivanovii. of these, l. monocytogenes is a well-known cause of abortion, encephalitis and septicaemia in man and animals. listeria ivanovii is an animal pathogen and in rare cases causes human infection. contamination of ovine carcasses during the slaughter and processing is a major risk for food...

Aim: This study investigates the prevalence of Listeria spp. in fresh produce sold in the Canterbury region of New Zealand. Background: L. monocytogenes is a common pathogenic bacterium that can be present and grow on fresh produce. Therefore, systematic risk assessment is needed to avoid a food safety scare. Results: Microbiological analysis to detect Listeria spp. in fresh produce samples sho...

For two large beef processing plants, one located in the southern United States (plant A) and one located in the northern United States (plant B), prevalence of Escherichia coli O157:H7, Listeria spp., Listeria monocytogenes, and Salmonella was determined for hide, carcass, and facility environmental samples over the course of 5 months. The prevalence of E. coli O157:H7 (68.1 versus 55.9%) and ...

Spleen cells of mice infected with Listeria monocytogenes were adoptively transferred to normal mice. Such lymphocytes conferred resistance to a lethal challenge with Listeria. Hyperimmunization of the donor reduces the number of cells necessary to transfer effective immunity. Such spleen cells if treated with anti-theta serum do not transfer resistance to Listeria. Hence, thymus (T) lymphocyte...

results the amount of hgbr2 (0.1% wt/vol) and cdso4 (0.2% wt/vol) were considered as lethal doses for l. monocytogenes ptcc 1297 (serotype 4a). different concentrations of pbo could not kill bacteria yet decreased their growth. the bacteria showed different morphologic and biochemical characteristics under each stressor. objectives the aim of this work was evaluate the growth, surface structure...

introduction: listeria monocytogenes is a serious concern for the food industry due to its high case fatality rate, widespread distribution, ability to survive a wide variety of food processing conditions, and the severity of the illness associated with this pathogen infection. the objective of this study was to determine the growth, cell morphology and biochemical characteristics of l. monocyt...

the innate immune system utilizes pattern recognition receptors (prrs) to recognize microbes. pathogens contain various molecules with diverse effects on immune response. in this study, we evaluated the effect of dna and protein components derived from two intracellular microorganisms including listeria monocytogenes (l.monocytogenes) and toxoplasma gondii (t. gondii) on dendritic cells (dcs) a...

objectives in this study, the effect of coating glass and steel surfaces by copper nanoparticles (cunps) in inhibiting the biofilm formation by listeria monocytogenes and pseudomonas aeruginosa was examined. materials and methods the minimal inhibitory concentrations (mics) of synthesized cunps were measured against l. monocytogenes and p. aeruginosa by using the broth-dilution method. the cell...