scholarly journals The role of metal oxide nanoparticles, Escherichia coli, and Lactobacillus rhamnosus on small intestinal enzyme activity

2020 ◽  
Vol 7 (12) ◽  
pp. 3940-3964
Author(s):  
Alba García-Rodríguez ◽  
Fabiola Moreno-Olivas ◽  
Ricard Marcos ◽  
Elad Tako ◽  
Cláudia N. H. Marques ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Enzyme Activity ◽  
Metal Oxide Nanoparticles ◽  
Lactobacillus Rhamnosus ◽  
Engineered Nanomaterials ◽  
Oxide Nanoparticles ◽  
Small Intestinal ◽  
Intestinal Enzyme

To understand the effects of engineered nanomaterials added intentionally and unintentionally to food, we improved a gastrointestinal in vitro model using in vitro digested nanoparticles, Caco-2/HT29-MTX cells and gut microbiota.

The Role of Microbiota and Metal Oxide Nanoparticles on Small Intestinal Enzyme Activity

2020 ◽  
Author(s):  
Alba García-Rodríguez ◽  
Fabiola Moreno-Olivas ◽  
Ricard Marcos ◽  
Elad Tako ◽  
Cláudia N. H. Marques ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Metal Oxide ◽  
Metal Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Small Intestinal ◽  
Intestinal Enzyme

Abstract The authors have removed this preprint from Research Square

scholarly journals Role of Intimin and Bundle-Forming Pili in Enteropathogenic Escherichia coli Adhesion to Pediatric Intestinal Tissue In Vitro

1998 ◽  
Vol 66 (4) ◽  
pp. 1570-1578 ◽  
Author(s):  
Susan Hicks ◽  
Gad Frankel ◽  
James B. Kaper ◽  
Gordon Dougan ◽  
Alan D. Phillips
Keyword(s):  
Escherichia Coli ◽  
Organ Culture ◽  
Single Amino Acid ◽  
Intestinal Biopsy ◽  
Virulence Plasmid ◽  
Lesion Formation ◽  
Intestinal Tissue ◽  
Small Intestinal

ABSTRACT Attaching and effacing (A/E) lesion formation is central to enteropathogenic Escherichia coli (EPEC) pathogenesis. In vitro experiments with human epithelial cell lines have implicated virulence plasmid-encoded bundle-forming pili (BFP) in initial binding and intimin in intimate attachment and A/E lesion formation. This study investigated the role of BFP and intimin in EPEC interactions with pediatric small intestinal biopsy tissue in in vitro organ culture. Organ culture infections (2 to 8 h) were performed with E2348/69 (a wild-type EPEC O127:H6 clinical isolate) and E2348/69 derivatives including CVD206 (eae deficient), CVD206(pCVD438) (eae-complemented CVD206), CVD206(pCVD438/01) (expressing intimin, which is nonfunctional due to a single amino acid substitution), JPN15 (spontaneous EPEC adherence factor virulence plasmid-cured E2348/69), and 31-6-1(1) (E2348/69 with a TnphoA insertion inactivation mutation in the virulence plasmid-encoded bfpA gene). Scanning and transmission electron microscopy revealed that after 8 h E2348/69 and CVD206(pCVD438) (both Int+ BFP+) adhered to all specimens, causing A/E lesions with surrounding microvillous elongation. JPN15 and 31-6-1(1) (both Int+BFP−) adhered and caused A/E lesions although bacteria adhered in “flat,” two-dimensional groups. CVD206 and CVD206(pCVD438/01) (both Int− BFP+) did not adhere to any sample, and no pathological tissue changes were seen. Thus, in human intestinal organ culture, BFP do not appear to be involved in the initial stages of EPEC nonintimate adhesion but are implicated in the formation of complex, three-dimensional colonies via bacterium-bacterium interactions. Intimin appears to play an essential role in establishing colonization of EPEC on pediatric small intestinal tissue.

scholarly journals Interaction of Enteropathogenic Escherichia coli with Human Intestinal Mucosa: Role of Effector Proteins in Brush Border Remodeling and Formation of Attaching and Effacing Lesions

2005 ◽  
Vol 73 (2) ◽  
pp. 1243-1251 ◽  
Author(s):  
Robert K Shaw ◽  
Jennifer Cleary ◽  
Michael S. Murphy ◽  
Gad Frankel ◽  
Stuart Knutton
Keyword(s):  
Escherichia Coli ◽  
Brush Border ◽  
Effector Proteins ◽  
Host Cells ◽  
Culture Model ◽  
Specific Effector ◽  
Subsequent Loss ◽  
Small Intestinal

ABSTRACT Enteropathogenic Escherichia coli (EPEC) strains deliver effector proteins Tir, EspB, Map, EspF, EspH, and EspG into host cells to induce brush border remodeling and produce attaching and effacing (A/E) lesions on small intestinal enterocytes. In this study, the role of individual EPEC effectors in brush border remodeling and A/E lesion formation was investigated with an in vitro human small intestinal organ culture model of EPEC infection and specific effector mutants. tir, map, espB, and espH mutants produced “footprint” phenotypes due to close bacterial adhesion but subsequent loss of bacteria; an espB mutant and other type III secretion system mutants induced a “noneffacing footprint” associated with intact brush border microvilli, whereas a tir mutant was able to efface microvilli resulting in an “effacing footprint”; map and espH mutants produced A/E lesions, but loss of bacteria resulted in a “pedestal footprint.” An espF mutant produced typical A/E lesions without associated microvillous elongation. An espG mutant was indistinguishable from the wild type. These observations indicate that Tir, Map, EspF, and EspH effectors play a role in brush border remodeling and production of mature A/E lesions.

scholarly journals Green Synthesis of CeO2 Nanoparticles from the Abelmoschus esculentus Extract: Evaluation of Antioxidant, Anticancer, Antibacterial, and Wound-Healing Activities

Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4659
Author(s):  
Hafiz Ejaz Ahmed ◽  
Yasir Iqbal ◽  
Muhammad Hammad Aziz ◽  
Muhammad Atif ◽  
Zahida Batool ◽  
...  
Keyword(s):  
Wound Healing ◽  
Metal Oxide Nanoparticles ◽  
In Vitro Cytotoxicity ◽  
Ceo2 Nanoparticles ◽  
Abelmoschus Esculentus ◽  
Oxide Nanoparticles ◽  
Dependent Manner ◽  
Hydrogel Membrane ◽  
Cancerous Cells

Metal oxide nanoparticles synthesized by the biological method represent the most recent research in nanotechnology. This study reports the rapid and ecofriendly approach for the synthesis of CeO2 nanoparticles mediated using the Abelmoschus esculentus extract. The medicinal plant extract acts as both a reducing and stabilizing agent. The characterization of CeO2 NPs was performed by scanning electron microscopy (SEM), X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-Vis), and Fourier transform infrared spectroscopy (FTIR). The in vitro cytotoxicity of green synthesized CeO2 was assessed against cervical cancerous cells (HeLa). The exposure of CeO2 to HeLa cells at 10–125 µg/mL caused a loss in cellular viability against cervical cancerous cells in a dose-dependent manner. The antibacterial activity of the CeO2 was assessed against S. aureus and K. pneumonia. A significant improvement in wound-healing progression was observed when cerium oxide nanoparticles were incorporated into the chitosan hydrogel membrane as a wound dressing.

scholarly journals Characterization of a Dye-Decolorizing Peroxidase from Irpex lacteus Expressed in Escherichia coli: An Enzyme with Wide Substrate Specificity Able to Transform Lignosulfonates

2021 ◽  
Vol 7 (5) ◽  
pp. 325
Author(s):  
Laura Isabel de de Eugenio ◽  
Rosa Peces-Pérez ◽  
Dolores Linde ◽  
Alicia Prieto ◽  
Jorge Barriuso ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Inclusion Bodies ◽  
Veratryl Alcohol ◽  
Dye Decolorization ◽  
Irpex Lacteus ◽  
Type D ◽  
Lignin Peroxidases

A dye-decolorizing peroxidase (DyP) from Irpex lacteus was cloned and heterologously expressed as inclusion bodies in Escherichia coli. The protein was purified in one chromatographic step after its in vitro activation. It was active on ABTS, 2,6-dimethoxyphenol (DMP), and anthraquinoid and azo dyes as reported for other fungal DyPs, but it was also able to oxidize Mn2+ (as manganese peroxidases and versatile peroxidases) and veratryl alcohol (VA) (as lignin peroxidases and versatile peroxidases). This corroborated that I. lacteus DyPs are the only enzymes able to oxidize high redox potential dyes, VA and Mn+2. Phylogenetic analysis grouped this enzyme with other type D-DyPs from basidiomycetes. In addition to its interest for dye decolorization, the results of the transformation of softwood and hardwood lignosulfonates suggest a putative biological role of this enzyme in the degradation of phenolic lignin.

scholarly journals Uptake and impacts of polyvinylpyrrolidone (PVP) capped metal oxide nanoparticles on Daphnia magna: role of core composition and acquired corona

2018 ◽  
Vol 5 (7) ◽  
pp. 1745-1756 ◽  
Author(s):  
S. M. Briffa ◽  
F. Nasser ◽  
E. Valsami-Jones ◽  
I. Lynch
Keyword(s):  
Metal Oxide ◽  
Daphnia Magna ◽  
Metal Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Core Composition

A key hypothesis in nanosafety assessment is that the NP core chemistry and eco-corona are primary factors controlling toxicity.

Calcium ATPase and intestinal calcium transport in uremic rats

1980 ◽  
Vol 238 (5) ◽  
pp. G424-G428
Author(s):  
H. Schiffl ◽  
U. Binswanger
Keyword(s):  
Enzyme Activity ◽  
Atpase Activity ◽  
Calcium Transport ◽  
Calcium Atpase ◽  
Intestinal Calcium Transport ◽  
Identical Response ◽  
Close Relationship ◽  
Intact Rats

Calcium ATPase, an enzyme involved in intestinal calcium transport, was measured in homogenates of duodenal mucosal scrapings of normal and uremic rats. The effects of calcium deprivation and treatment with 1 alpha,25-dihydroxycholecalciferol [1,25-(OH)2D3] were investigated as well. Uremia decreased the enzyme activity and impaired the rise after calcium deprivation as observed in intact rats. The 1,25-(OH)2D3 treatment increased the enzyme activity in uremic animals and resulted in an identical response to calcium deprivation as observed in intact rats; parathyroidectomy abolished this effect. A striking correlation between everted duodenal gut sac calcium transport and calcium ATPase activity could be demonstrated for all groups of rats studied. It is concluded that the calcium ATPase activity is linked to the production of 1,25-(OH)2D3 as well as to an additional factor, probably parathyroid hormone. The close relationship between enzyme activity and in vitro calcium transport, even during constant physiological supplementation with 1,25-(OH)2D3, suggests an autonomous role of the calcium ATPase activity for mediation of calcium transport in the duodenum in addition to the well-known mechanisms related to vitamin D and its metabolites.

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