The Experts below are selected from a list of 273 Experts worldwide ranked by ideXlab platform
Kumar Venkitanarayanan - One of the best experts on this subject based on the ideXlab platform.
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Sub-Inhibitory Concentrations of Trans-Cinnamaldehyde Attenuate Virulence in Cronobacter sakazakii in Vitro
International journal of molecular sciences, 2014Co-Authors: Mary Anne Roshni Amalaradjou, Kwang Sik Kim, Kumar VenkitanarayananAbstract:Cronobacter sakazakii is a foodborne pathogen, which causes a life-threatening form of meningitis, Necrotizing Colitis and meningoencephalitis in neonates and children. Epidemiological studies implicate dried infant formula as the principal source of C. sakazakii. In this study, we investigated the efficacy of sub-inhibitory concentrations (SIC) of trans-cinnamaldehyde (TC), an ingredient in cinnamon, for reducing C. sakazakii virulence in vitro using cell culture, microscopy and gene expression assays. TC significantly (p ≤ 0.05) suppressed C. sakazakii adhesion to and invasion of human and rat intestinal epithelial cells, and human brain microvascular endothelial cells. In addition, TC inhibited C. sakazakii survival and replication in human macrophages. We also observed that TC reduced the ability of C. sakazakii to cause cell death in rat intestinal cells, by inhibiting nitric oxide production. Results from gene expression studies revealed that TC significantly downregulated the virulence genes critical for motility, host tissue adhesion and invasion, macrophage survival, and LPS (Lipopolysaccharide) synthesis in C. sakazakii. The efficacy of TC in attenuating these major virulence factors in C. sakazakii underscores its potential use in the prevention and/or control of infection caused by this pathogen.
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Article Sub-Inhibitory Concentrations of Trans-Cinnamaldehyde Attenuate Virulence in Cronobacter sakazakii in Vitro
2014Co-Authors: Mary Anne, Kwang Sik Kim, Roshni Amalaradjou, Kumar VenkitanarayananAbstract:Abstract: Cronobacter sakazakii is a foodborne pathogen, which causes a life-threatening form of meningitis, Necrotizing Colitis and meningoencephalitis in neonates and children. Epidemiological studies implicate dried infant formula as the principal source of C. sakazakii. In this study, we investigated the efficacy of sub-inhibitory concentrations (SIC) of trans-cinnamaldehyde (TC), an ingredient in cinnamon, for reducing C. sakazakii virulence in vitro using cell culture, microscopy and gene expression assays. TC significantly (p ≤ 0.05) suppressed C. sakazakii adhesion to and invasion of human and rat intestinal epithelial cells, and human brain microvascular endothelial cells. In addition, TC inhibited C. sakazakii survival and replication in human macrophages. We also observed that TC reduced the ability of C. sakazakii to cause cell death in rat intestinal cells, by inhibiting nitric oxide production. Results from gene expression studies revealed that TC significantly downregulated the virulence genes critical for motility, host tissue adhesion and invasion, macrophage survival, and LPS (Lipopolysaccharide) synthesis in C. sakazakii. The efficacy of TC in attenuating these major virulence factors in C. sakazakii underscores its potential use in the prevention and/or control of infection caused by this pathogen
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Inactivation of Enterobacter sakazakii in reconstituted infant formula by trans-cinnamaldehyde
International journal of food microbiology, 2008Co-Authors: Mary Anne Roshni Amalaradjou, Thomas Hoagland, Kumar VenkitanarayananAbstract:Enterobacter sakazakii is an emerging pathogen which causes a life-threatening form of meningitis, Necrotizing Colitis and meningoencephalitis in neonates and children. Epidemiological studies implicate dried infant formula as the principal source of the pathogen. Trans-cinnamaldehyde is a major component of bark extract of cinnamon. It is classified as generally recognized as safe (GRAS) by the U.S. Food and Drug Administration, and is approved for use in food (21 CFR 182.60). The objective of this study was to determine the antibacterial effect of trans-cinnamaldehyde on E. sakazakii in reconstituted infant formula. A 5-strain mixture of E. sakazakii was inoculated into 10 ml samples of reconstituted infant formula (at 6.0 log CFU/ml) containing 0%, 0.15%, 0.3% or 0.5% trans-cinnamaldehyde. The samples were incubated at 37, 23, 8 or 4 °C for 0, 6, 10 and 24 h, and the surviving populations of E. sakazakii at each sampling time were enumerated. In addition, potential cytotoxicity of trans-cinnamaldehyde, if any, was determined on human embryonic intestinal cells (INT-407). The treatments containing trans-cinnamaldehyde significantly reduced (P < 0.05) the population of E. sakazakii, compared to the controls. Trans-cinnamaldehyde (0.5%) reduced the pathogen to undetectable levels by 4 h of incubation at 37 or 23 °C and 10 h of incubation at 8 or 4 °C, respectively. Trans-cinnamaldehyde produced no cytotoxic effects on human embryonic intestinal cells at the tested concentrations. Results indicate that trans-cinnamaldehyde could potentially be used to kill E. sakazakii in reconstituted infant formula, however sensory studies are warranted before recommending its use.
Mary Anne Roshni Amalaradjou - One of the best experts on this subject based on the ideXlab platform.
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Sub-Inhibitory Concentrations of Trans-Cinnamaldehyde Attenuate Virulence in Cronobacter sakazakii in Vitro
International journal of molecular sciences, 2014Co-Authors: Mary Anne Roshni Amalaradjou, Kwang Sik Kim, Kumar VenkitanarayananAbstract:Cronobacter sakazakii is a foodborne pathogen, which causes a life-threatening form of meningitis, Necrotizing Colitis and meningoencephalitis in neonates and children. Epidemiological studies implicate dried infant formula as the principal source of C. sakazakii. In this study, we investigated the efficacy of sub-inhibitory concentrations (SIC) of trans-cinnamaldehyde (TC), an ingredient in cinnamon, for reducing C. sakazakii virulence in vitro using cell culture, microscopy and gene expression assays. TC significantly (p ≤ 0.05) suppressed C. sakazakii adhesion to and invasion of human and rat intestinal epithelial cells, and human brain microvascular endothelial cells. In addition, TC inhibited C. sakazakii survival and replication in human macrophages. We also observed that TC reduced the ability of C. sakazakii to cause cell death in rat intestinal cells, by inhibiting nitric oxide production. Results from gene expression studies revealed that TC significantly downregulated the virulence genes critical for motility, host tissue adhesion and invasion, macrophage survival, and LPS (Lipopolysaccharide) synthesis in C. sakazakii. The efficacy of TC in attenuating these major virulence factors in C. sakazakii underscores its potential use in the prevention and/or control of infection caused by this pathogen.
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Inactivation of Enterobacter sakazakii in reconstituted infant formula by trans-cinnamaldehyde
International journal of food microbiology, 2008Co-Authors: Mary Anne Roshni Amalaradjou, Thomas Hoagland, Kumar VenkitanarayananAbstract:Enterobacter sakazakii is an emerging pathogen which causes a life-threatening form of meningitis, Necrotizing Colitis and meningoencephalitis in neonates and children. Epidemiological studies implicate dried infant formula as the principal source of the pathogen. Trans-cinnamaldehyde is a major component of bark extract of cinnamon. It is classified as generally recognized as safe (GRAS) by the U.S. Food and Drug Administration, and is approved for use in food (21 CFR 182.60). The objective of this study was to determine the antibacterial effect of trans-cinnamaldehyde on E. sakazakii in reconstituted infant formula. A 5-strain mixture of E. sakazakii was inoculated into 10 ml samples of reconstituted infant formula (at 6.0 log CFU/ml) containing 0%, 0.15%, 0.3% or 0.5% trans-cinnamaldehyde. The samples were incubated at 37, 23, 8 or 4 °C for 0, 6, 10 and 24 h, and the surviving populations of E. sakazakii at each sampling time were enumerated. In addition, potential cytotoxicity of trans-cinnamaldehyde, if any, was determined on human embryonic intestinal cells (INT-407). The treatments containing trans-cinnamaldehyde significantly reduced (P < 0.05) the population of E. sakazakii, compared to the controls. Trans-cinnamaldehyde (0.5%) reduced the pathogen to undetectable levels by 4 h of incubation at 37 or 23 °C and 10 h of incubation at 8 or 4 °C, respectively. Trans-cinnamaldehyde produced no cytotoxic effects on human embryonic intestinal cells at the tested concentrations. Results indicate that trans-cinnamaldehyde could potentially be used to kill E. sakazakii in reconstituted infant formula, however sensory studies are warranted before recommending its use.
Kwang Sik Kim - One of the best experts on this subject based on the ideXlab platform.
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Sub-Inhibitory Concentrations of Trans-Cinnamaldehyde Attenuate Virulence in Cronobacter sakazakii in Vitro
International journal of molecular sciences, 2014Co-Authors: Mary Anne Roshni Amalaradjou, Kwang Sik Kim, Kumar VenkitanarayananAbstract:Cronobacter sakazakii is a foodborne pathogen, which causes a life-threatening form of meningitis, Necrotizing Colitis and meningoencephalitis in neonates and children. Epidemiological studies implicate dried infant formula as the principal source of C. sakazakii. In this study, we investigated the efficacy of sub-inhibitory concentrations (SIC) of trans-cinnamaldehyde (TC), an ingredient in cinnamon, for reducing C. sakazakii virulence in vitro using cell culture, microscopy and gene expression assays. TC significantly (p ≤ 0.05) suppressed C. sakazakii adhesion to and invasion of human and rat intestinal epithelial cells, and human brain microvascular endothelial cells. In addition, TC inhibited C. sakazakii survival and replication in human macrophages. We also observed that TC reduced the ability of C. sakazakii to cause cell death in rat intestinal cells, by inhibiting nitric oxide production. Results from gene expression studies revealed that TC significantly downregulated the virulence genes critical for motility, host tissue adhesion and invasion, macrophage survival, and LPS (Lipopolysaccharide) synthesis in C. sakazakii. The efficacy of TC in attenuating these major virulence factors in C. sakazakii underscores its potential use in the prevention and/or control of infection caused by this pathogen.
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Article Sub-Inhibitory Concentrations of Trans-Cinnamaldehyde Attenuate Virulence in Cronobacter sakazakii in Vitro
2014Co-Authors: Mary Anne, Kwang Sik Kim, Roshni Amalaradjou, Kumar VenkitanarayananAbstract:Abstract: Cronobacter sakazakii is a foodborne pathogen, which causes a life-threatening form of meningitis, Necrotizing Colitis and meningoencephalitis in neonates and children. Epidemiological studies implicate dried infant formula as the principal source of C. sakazakii. In this study, we investigated the efficacy of sub-inhibitory concentrations (SIC) of trans-cinnamaldehyde (TC), an ingredient in cinnamon, for reducing C. sakazakii virulence in vitro using cell culture, microscopy and gene expression assays. TC significantly (p ≤ 0.05) suppressed C. sakazakii adhesion to and invasion of human and rat intestinal epithelial cells, and human brain microvascular endothelial cells. In addition, TC inhibited C. sakazakii survival and replication in human macrophages. We also observed that TC reduced the ability of C. sakazakii to cause cell death in rat intestinal cells, by inhibiting nitric oxide production. Results from gene expression studies revealed that TC significantly downregulated the virulence genes critical for motility, host tissue adhesion and invasion, macrophage survival, and LPS (Lipopolysaccharide) synthesis in C. sakazakii. The efficacy of TC in attenuating these major virulence factors in C. sakazakii underscores its potential use in the prevention and/or control of infection caused by this pathogen
Di Meng - One of the best experts on this subject based on the ideXlab platform.
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Indole-3-lactic acid, a metabolite of tryptophan, secreted by Bifidobacterium longum subspecies infantis is anti-inflammatory in the immature intestine
Pediatric Research, 2020Co-Authors: Di Meng, Eduardo Sommella, Emanuela Salviati, Pietro Campiglia, Kriston Ganguli, Karim Djebali, Weishu Zhu, W. Allan WalkerAbstract:Background Necrotizing enteroColitis (NEC), a necrotic inflammation of the intestine, represents a major health problem in the very premature infant. Although prevention is difficult, the combination of ingestion of maternal-expressed breastmilk in conjunction with a probiotic provides the best protection. In this study, we establish a mechanism for breastmilk/probiotic protection. Methods Ultra-high-performance liquid chromatography-tandem mass spectrometry of Bifidobacterium longum subsp. infantis ( B. infantis ) secretions was used to identify an anti-inflammatory molecule. Indole-3-lactic acid (ILA) was then tested in an established human immature small intestinal cell line, Necrotizing Colitis enterocytes, and other immature human enteroids for anti-inflammatory effects and to establish developmental function. ILA was also examined in immature and mature enterocytes. Results We have identified ILA, a metabolite of breastmilk tryptophan, as the anti-inflammatory molecule. This molecule is developmentally functional in immature but not mature intestinal enterocytes; ILA reduces the interleukin-8 (IL-8) response after IL-1β stimulus. It interacts with the transcription factor aryl hydrocarbon receptor (AHR) and prevents transcription of the inflammatory cytokine IL-8. Conclusions This molecule produced by B. infantis (ATCC No. 15697) interaction with ingested breastmilk functions in a complementary manner and could become useful in the treatment of all at-risk premature infants for NEC if safety and clinical studies are performed.
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indole 3 lactic acid a metabolite of tryptophan secreted by bifidobacterium longum subspecies infantis is anti inflammatory in the immature intestine
Pediatric Research, 2020Co-Authors: Di Meng, Eduardo Sommella, Emanuela Salviati, Pietro Campiglia, Kriston Ganguli, Karim Djebali, Weishu Zhu, Allan W WalkerAbstract:Necrotizing enteroColitis (NEC), a necrotic inflammation of the intestine, represents a major health problem in the very premature infant. Although prevention is difficult, the combination of ingestion of maternal-expressed breastmilk in conjunction with a probiotic provides the best protection. In this study, we establish a mechanism for breastmilk/probiotic protection. Ultra-high-performance liquid chromatography-tandem mass spectrometry of Bifidobacterium longum subsp. infantis (B. infantis) secretions was used to identify an anti-inflammatory molecule. Indole-3-lactic acid (ILA) was then tested in an established human immature small intestinal cell line, Necrotizing Colitis enterocytes, and other immature human enteroids for anti-inflammatory effects and to establish developmental function. ILA was also examined in immature and mature enterocytes. We have identified ILA, a metabolite of breastmilk tryptophan, as the anti-inflammatory molecule. This molecule is developmentally functional in immature but not mature intestinal enterocytes; ILA reduces the interleukin-8 (IL-8) response after IL-1β stimulus. It interacts with the transcription factor aryl hydrocarbon receptor (AHR) and prevents transcription of the inflammatory cytokine IL-8. This molecule produced by B. infantis (ATCC No. 15697) interaction with ingested breastmilk functions in a complementary manner and could become useful in the treatment of all at-risk premature infants for NEC if safety and clinical studies are performed.
Francisco A. Uzal - One of the best experts on this subject based on the ideXlab platform.
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Epsilon toxin is essential for the virulence of Clostridium perfringens type D infection in sheep, goats, and mice.
Infection and immunity, 2013Co-Authors: Jorge P. Garcia, Bruce A. Mcclane, Victoria Michelle Adams, Juliann Beingesser, Meredith Lesley Hughes, Rachael Poon, Dena Lyras, Ashley E. Hill, Julian I. Rood, Francisco A. UzalAbstract:Clostridium perfringens type D causes disease in sheep, goats, and other ruminants. Type D isolates produce, at minimum, alpha and epsilon (ETX) toxins, but some express up to five different toxins, raising questions about which toxins are necessary for the virulence of these bacteria. We evaluated the contribution of ETX to C. perfringens type D pathogenicity in an intraduodenal challenge model in sheep, goats, and mice using a virulent C. perfringens type D wild-type strain (WT), an isogenic ETX null mutant (etx mutant), and a strain where the etx mutation has been reversed (etx complemented). All sheep and goats, and most mice, challenged with the WT isolate developed acute clinical disease followed by death in most cases. Sheep developed various gross and/or histological changes that included edema of brain, lungs, and heart as well as hydropericardium. Goats developed various effects, including Necrotizing Colitis, pulmonary edema, and hydropericardium. No significant gross or histological abnormalities were observed in any mice infected with the WT strain. All sheep, goats, and mice challenged with the isogenic etx mutant remained clinically healthy for ≥24 h, and no gross or histological abnormalities were observed in those animals. Complementation of etx knockout restored virulence; most goats, sheep, and mice receiving this complemented mutant developed clinical and pathological changes similar to those observed in WT-infected animals. These results indicate that ETX is necessary for type D isolates to induce disease, supporting a key role for this toxin in type D disease pathogenesis.
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Fatal Necrotizing Colitis Following a Foodborne Outbreak of Enterotoxigenic Clostridium perfringens Type A Infection
Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, 2005Co-Authors: John E. Bos, Lauri Smithee, Bruce A. Mcclane, R. F. Distefano, Francisco A. Uzal, J. Glenn Songer, Sue Mallonee, James M. CrutcherAbstract:BACKGROUND Enterotoxigenic Clostridium perfringens type A is the third leading cause of foodborne disease in the United States, resulting annually in an estimated 250,000 cases of a typically mild, self-limiting gastrointestinal illness. METHODS A retrospective cohort study was conducted to determine the cause of a small cluster of cases of gastrointestinal illness, which included cases of severe Necrotizing Colitis. Participants in the study consisted of residents and staff of a residential care facility for the mentally ill in Oklahoma (n = 20). An inspection of food preparation and food storage areas of the residential care facility was conducted as part of an environmental investigation. The investigation included extensive microbiological and molecular testing of the C. perfringens isolates and tissue specimens collected at autopsy. RESULTS A total of 7 (3 confirmed and 4 probable) cases of foodborne enterotoxigenic C. perfringens type A were identified (attack rate, 35%) after the consumption of high-risk foods. Three residents developed acute Necrotizing Colitis; 2 of them died. Each patient with confirmed infection presented with evidence of constipation or fecal impaction. C. perfringens enterotoxin (CPE)-positive C. perfringens type A was cultured on samples from each patient with Necrotizing Colitis. Although statistical analyses failed to implicate a food source, the isolates carried a chromosomal cpe gene, which supports a foodborne origin. CONCLUSIONS This study confirms that foodborne CPE-positive C. perfringens type A can affect the colon, resulting in potentially fatal Necrotizing Colitis. Drug-induced constipation and fecal impaction, resulting in prolonged exposure of the colonic mucosal tissue to C. perfringens type A toxins, contributed to the development of Necrotizing Colitis.
