scholarly journals The Listeria monocytogenes Virulence Factor InlJ Is Specifically Expressed In Vivo and Behaves as an Adhesin

2008 ◽  
Vol 76 (4) ◽  
pp. 1368-1378 ◽  
Author(s):  
Christophe Sabet ◽  
Alejandro Toledo-Arana ◽  
Nicolas Personnic ◽  
Marc Lecuit ◽  
Sarah Dubrac ◽  
...  
Keyword(s):  
Listeria Monocytogenes ◽  
Cultured Cells ◽  
Brain Heart Infusion ◽  
Gene Encoding ◽  
Regulatory Pathways ◽  
Food Borne ◽  
Food Body ◽  
Brain Heart Infusion Medium

ABSTRACT The food-borne pathogen Listeria monocytogenes is adapted to a diversity of environments, such as soil, food, body fluids, and the cytosol of eukaryotic cells. The transition between saprophytic and pathogenic life is mediated through complex regulatory pathways that modulate the expression of virulence factors. Here we examined the expression of inlJ, a recently identified gene encoding a protein of the LPXTG-internalin family and involved in pathogenesis. We show that inlJ expression is controlled neither by the major listerial regulator of virulence genes, PrfA, nor by AxyR, a putative AraC regulator encoded by a gene adjacent to inlJ and divergently transcribed. The InlJ protein is not produced by bacteria grown in vitro in brain heart infusion medium or replicating in the cytosol of tissue-cultured cells. In contrast, it is efficiently produced and localized at the surface of bacteria present in the liver and blood of infected animals. Strikingly, the expression of inlJ by a heterologous promoter in L. monocytogenes or L. innocua promotes bacterial adherence to human cells in vitro. Taken together, these results strongly suggest that InlJ acts as a novel L. monocytogenes sortase-anchored adhesin specifically expressed during infection in vivo.

Metal oxide nanoparticle-functionalized sebacic acid-grafted PHEAM nanocarriers for enriched activity of metronidazole against food borne bacteria: in vitro and in vivo study

2018 ◽  
Vol 42 (22) ◽  
pp. 18437-18447 ◽  
Author(s):  
Murugesan Gowri ◽  
Kannan Suganya ◽  
Nachimuthu Latha ◽  
Marudhamuthu Murugan ◽  
Mukhtar Ahmed ◽  
...  
Keyword(s):  
Listeria Monocytogenes ◽  
Metal Oxide ◽  
Sebacic Acid ◽  
In Vivo Study ◽  
Metal Oxide Nanoparticle ◽  
Food Borne ◽  
Oxide Nanoparticle

Food borne infection is a serious complication caused by Listeria monocytogenes (L. monocytogenes), a dangerous bacteria.

scholarly journals Endometriosis and Phytoestrogens: Friends or Foes? A Systematic Review

Nutrients ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 2532
Author(s):  
Ludovica Bartiromo ◽  
Matteo Schimberni ◽  
Roberta Villanacci ◽  
Jessica Ottolina ◽  
Carolina Dolci ◽  
...  
Keyword(s):  
Systematic Review ◽  
Animal Models ◽  
Cultured Cells ◽  
Regulatory Pathways ◽  
Medical Databases ◽  
Lesion Growth ◽  
Experimental Findings

The aim of this systematic review was to provide comprehensive and available data on the possible role of phytoestrogens (PE) for the treatment of endometriosis. We conducted an advanced, systematic search of online medical databases PubMed and Medline. Only full-length manuscripts written in English up to September 2020 were considered. A total of 60 studies were included in the systematic review. According to in vitro findings, 19 out of 22 studies reported the ability of PE in inducing anti-proliferative, anti-inflammatory and proapoptotic effects on cultured cells. Various mechanisms have been proposed to explain this in vitro action including the alteration of cell cycle proteins, the activation/inactivation of regulatory pathways, and modification of radical oxidative species levels. Thirty-eight articles on the effects of phytoestrogens on the development of endometriotic lesions in in vivo experimental animal models of endometriosis have been included. In line with in vitro findings, results also derived from animal models of endometriosis generally supported a beneficial effect of the compounds in reducing lesion growth and development. Finally, only seven studies investigated the effects of phytoestrogens intake on endometriosis in humans. The huge amount of in vitro and in vivo animal findings did not correspond to a consistent literature in the women affected. Therefore, whether the experimental findings can be translated in women is currently unknown.

Apoptotic Death of Listeria Monocytogenes-Infected Human Macrophages Induced by Lactoferricin B, A Bovine Lactoferrin-Derived Peptide

2005 ◽  
Vol 18 (2) ◽  
pp. 317-325 ◽  
Author(s):  
C. Longhi ◽  
M. P. Conte ◽  
S. Ranaldi ◽  
M. Penta ◽  
P. Valenti ◽  
...  
Keyword(s):  
Listeria Monocytogenes ◽  
Bovine Milk ◽  
Cell Types ◽  
Bovine Lactoferrin ◽  
Human Macrophages ◽  
Apoptotic Death ◽  
Food Borne ◽  
Ifn Γ

Listeria monocytogenes, an intracellular facultative food-borne pathogen, was reported to induce apoptosis in vitro and in vivo in a variety of cell types with the exception of murine macrophages. These cells represent the predominant compartment of bacterial multiplication and die as a result of necrosis. In this study we showed that human non-activated and IFN-γ-activated macrophagic-like (THP-1) cells infected with L. monocytogenes, mainly die by necrosis rather than by an apoptotic process. Two natural products derived from bovine milk, lactoferrin and its derivative peptide lactoferricin B, are capable of regulating the fate of infected human macrophages. Bovine lactoferrin treatment of macrophages protects them from L. monocytogenes-induced death whereas lactoferricin B, its derivative peptide, determines a shifting of the equilibrium from necrosis to apoptosis.

scholarly journals Amoxicillin dose-effect relationship with Streptococcus pneumoniae in a mouse pneumonia model and roles of in vitro penicillin susceptibilities, autolysis, and tolerance properties of the strains.

1996 ◽  
Vol 40 (4) ◽  
pp. 941-946 ◽  
Author(s):  
E Azoulay-Dupuis ◽  
P Moine ◽  
J P Bedos ◽  
V Rieux ◽  
E Vallee
Keyword(s):  
Brain Heart Infusion ◽  
Bactericidal Effect ◽  
Dose Effect ◽  
Bacterial Killing ◽  
Resistant Strains ◽  
Two Populations ◽  
Brain Heart Infusion Medium ◽  
In Vitro Treatment

We used a mouse model of pneumococcal pneumonia to assess the bactericidal effect of increasing doses of amoxicillin (AMX) against clinical strains with various susceptibilities to penicillin. Twelve strains that exhibited similar virulence in mice were selected. Three were penicillin susceptible (PS) (penicillin and AMX MICs = 0.01 to 0.03 microgram/ml), three were intermediately resistant (PIR) (penicillin and AMX MICs = 0.5 to 1 microgram/ml), and six were penicillin resistant (PR) (penicillin and AMX MICs = 1 to 8 micrograms/ml). Leukopenic Swiss mice were infected intratracheally with 10(7) CFU of each strain. Treatment was initiated 3 h after infection and consisted of a single subcutaneous injection of AMX at doses ranging from 2.5 to 10 mg/kg (PS strains), 5 to 100 (PIR strains), and 25 to 3,000 (PR strains). Bacterial killing kinetics were recorded in the lungs over 9 h. The maximal log CFU reduction (Emax) was observed 3 h postinjection. The relation between Emax and log10(dose/MIC) showed two populations. With seven strains (the three PS, the three PIR, and one of the six PR [MICs, penicillin/AMX = 4/1]) a good correlation was observed between Emax and log10(dose/MIC) (r = 0.772; P < 0.02). A bactericidal effect equal to 3.5 log10 CFU was observed at a log10(dose/MIC) = 2. At this ratio, with the five other PR strains, Emax varied from 0.4 to 1.6 log10 CFU. In brain heart infusion medium containing AMX at 50 times the relevant MIC, these five PR strains were tolerant in vitro. Treatment failure with AMX was found in vivo, with tolerant, highly resistant strains.

Ultrastructural Correlations between Clonal Human Tumor Colonies and in Vivo Neoplasms

1982 ◽  
Vol 40 ◽  
pp. 210-211
Author(s):  
M.J. Murphy ◽  
R.R. Price ◽  
J.C. Sloman
Keyword(s):  
Cultured Cells ◽  
Human Tumor ◽  
Cell Type ◽  
Tumor Mass ◽  
Initial Cell ◽  
Cloning Assay ◽  
Human Tumor Cloning ◽  
The Relationship

The in vitro human tumor cloning assay originally described by Salmon and Hamburger has been applied recently to the investigation of differential anti-tumor drug sensitivities over a broad range of human neoplasms. A major problem in the acceptance of this technique has been the question of the relationship between the cultured cells and the original patient tumor, i.e., whether the colonies that develop derive from the neoplasm or from some other cell type within the initial cell population. A study of the ultrastructural morphology of the cultured cells vs. patient tumor has therefore been undertaken to resolve this question. Direct correlation was assured by division of a common tumor mass at surgical resection, one biopsy being fixed for TEM studies, the second being rapidly transported to the laboratory for culture.

Preparation of cultured astrocytes for x-ray microanalysis

1989 ◽  
Vol 47 ◽  
pp. 988-989
Author(s):  
N.K.R. Smith ◽  
K.E. Hunter ◽  
P. Mobley ◽  
L.P. Felpel
Keyword(s):  
Cultured Cells ◽  
Elemental Content ◽  
Elemental Distribution ◽  
Sprague Dawley ◽  
X Ray ◽  
Cultured Astrocytes ◽  
Freeze Dried ◽  
Ultimate Objective

Electron probe energy dispersive x-ray microanalysis (XRMA) offers a powerful tool for the determination of intracellular elemental content of biological tissue. However, preparation of the tissue specimen , particularly excitable central nervous system (CNS) tissue , for XRMA is rather difficult, as dissection of a sample from the intact organism frequently results in artefacts in elemental distribution. To circumvent the problems inherent in the in vivo preparation, we turned to an in vitro preparation of astrocytes grown in tissue culture. However, preparations of in vitro samples offer a new and unique set of problems. Generally, cultured cells, growing in monolayer, must be harvested by either mechanical or enzymatic procedures, resulting in variable degrees of damage to the cells and compromised intracel1ular elemental distribution. The ultimate objective is to process and analyze unperturbed cells. With the objective of sparing others from some of the same efforts, we are reporting the considerable difficulties we have encountered in attempting to prepare astrocytes for XRMA.Tissue cultures of astrocytes from newborn C57 mice or Sprague Dawley rats were prepared and cultured by standard techniques, usually in T25 flasks, except as noted differently on Cytodex beads or on gelatin. After different preparative procedures, all samples were frozen on brass pins in liquid propane, stored in liquid nitrogen, cryosectioned (0.1 μm), freeze dried, and microanalyzed as previously reported.

scholarly journals Probiotic and Functional Properties of Limosilactobacillus reuteri INIA P572

Nutrients ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1860
Author(s):  
Patricia Diez-Echave ◽  
Izaskun Martín-Cabrejas ◽  
José Garrido-Mesa ◽  
Susana Langa ◽  
Teresa Vezza ◽  
...  
Keyword(s):  
In Vitro Assays ◽  
Immunomodulatory Activity ◽  
Probiotic Properties ◽  
Protective Effects ◽  
Mice Model ◽  
In Vivo Models ◽  
Food Borne ◽  
Gastrointestinal Conditions

Limosilactobacillus reuteri INIA P572 is a strain able to produce the antimicrobial compound reuterin in dairy products, exhibiting a protective effect against some food-borne pathogens. In this study, we investigated some probiotic properties of this strain such as resistance to gastrointestinal passage or to colonic conditions, reuterin production in a colonic environment, and immunomodulatory activity, using different in vitro and in vivo models. The results showed a high resistance of this strain to gastrointestinal conditions, as well as capacity to grow and produce reuterin in a human colonic model. Although the in vitro assays using the RAW 264.7 macrophage cell line did not demonstrate direct immunomodulatory properties, the in vivo assays using a Dextran Sulphate Sodium (DSS)-induced colitic mice model showed clear immunomodulatory and protective effects of this strain.

scholarly journals TAMI-06. PRECLINICAL MODELS REVEAL BRAIN-MICROENVIRONMENT SPECIFIC METABOLIC DEPENDENCIES IN GLIOBLASTOMA

2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii214-ii214
Author(s):  
Jenna Minami ◽  
Nicholas Bayley ◽  
Christopher Tse ◽  
Henan Zhu ◽  
Danielle Morrow ◽  
...  
Keyword(s):  
Tumor Microenvironment ◽  
Cultured Cells ◽  
Tumor Biology ◽  
Metabolic Reprogramming ◽  
Neoplastic Progression ◽  
Extracellular Milieu ◽  
Metabolic Defects ◽  
Metabolic Heterogeneity

Abstract Metabolic reprogramming is a hallmark of cancer, and malignant cells must acquire metabolic adaptations to fuel neoplastic progression. Mutations or changes in metabolic gene expression can impose nutrient dependencies in tumors, and even in the absence of metabolic defects, cancer cells can become auxotrophic for particular nutrients or metabolic byproducts generated by other cells in the tumor microenvironment (TME). Conventional cell lines do not recapitulate the metabolic heterogeneity of glioblastoma (GBM), while primary cultured cells do not account for the influences of the microenvironment and the blood brain barrier on tumor biology. Additionally, these systems are under strong selective pressure divergent from that in vivo, leading to reduced heterogeneity between cultured tumor cells. Here, we describe a biobank of direct-from-patient derived orthotopic xenografts (GliomaPDOX) and gliomaspheres that reveal a subset of gliomas that, while able to form in vivo, cannot survive in vitro. RNA sequencing of tumors that can form both in vivo and in vitro (termed “TME-Indifferent”) compared to that of tumors that can only form in vivo (termed “TME-Dependent”) revealed transcriptional changes associated with altered nutrient availability, emphasizing the unique metabolic programs impacted by the tumor microenvironment. Furthermore, TME-dependent tumors lack metabolic signatures associated with nutrient biosynthesis, thus indicating a potential dependency of these tumors on scavenging specific nutrients from the extracellular milieu. Collectively, these data emphasize the metabolic heterogeneity within GBM, and reveal a subset of gliomas that lack metabolic plasticity, indicating a potential brain-microenvironment specific metabolic dependency that can be targeted for therapy.

scholarly journals Effect of Gaseous Ozone on Listeria monocytogenes Planktonic Cells and Biofilm: An In Vitro Study

Foods ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1484
Author(s):  
Felice Panebianco ◽  
Selene Rubiola ◽  
Francesco Chiesa ◽  
Tiziana Civera ◽  
Pierluigi Aldo Di Ciccio
Keyword(s):  
Listeria Monocytogenes ◽  
In Vitro Study ◽  
Planktonic Cells ◽  
Free Living ◽  
Biofilm Inhibition ◽  
Additional Tool ◽  
Complete Inactivation ◽  
Gaseous Ozone ◽  
Food Borne

Among food-borne pathogens, Listeria monocytogenes continues to pose concerns to food business operators due to its capacity to form biofilm in processing environments. Ozone may be an eco-friendly technology to control microbial contaminations, but data concerning its effect on Listeria monocytogenes biofilm are still limited. In this study, the effect of gaseous ozone at 50 ppm on planktonic cells and biofilm of reference and food-related Listeria monocytogenes strains was evaluated. Ozone caused a reduction in microbial loads of 3.7 ± 0.4 and 3.9 ± 0.4 Log10 CFU/mL after 10 and 30 min, respectively. A complete inactivation of planktonic cells after 6 h of treatment was observed. Biofilm inhibition and eradication treatments (50 ppm, 6 h) resulted in a significant decrease of the biofilm biomass for 59% of the strains tested, whilst a slight dampening of live cell loads in the biofilm state was observed. In conclusion, gaseous ozone is not sufficient to completely counteract Listeria monocytogenes biofilm, but it may be useful as an additional tool to contrast Listeria monocytogenes free-living cells and to improve the existing sanitization procedures in food processing environments.

scholarly journals Reversal of senescence-associated beta-galactosidase expression during in vitro three-dimensional tissue-engineering of human chondrocytes in a polymer scaffold

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shojiro Katoh ◽  
Atsuki Fujimaru ◽  
Masaru Iwasaki ◽  
Hiroshi Yoshioka ◽  
Rajappa Senthilkumar ◽  
...  
Keyword(s):  
Regenerative Medicine ◽  
Replicative Senescence ◽  
Cultured Cells ◽  
Three Dimensional ◽  
Human Chondrocytes ◽  
Cartilage Tissue ◽  
Optimal Method ◽  
Beta Galactosidase

AbstractRegenerative medicine applications require cells that are not inflicted with senescence after in vitro culture for an optimal in vivo outcome. Methods to overcome replicative senescence include genomic modifications which have their own disadvantages. We have evaluated a three-dimensional (3D) thermo-reversible gelation polymer (TGP) matrix environment for its capabilities to reverse cellular senescence. The expression of senescence-associated beta-galactosidase (SA-βgal) by human chondrocytes from osteoarthritis-affected cartilage tissue, grown in a conventional two-dimensional (2D) monolayer culture versus in 3D-TGP were compared. In 2D, the cells de-differentiated into fibroblasts, expressed higher SA-βgal and started degenerating at 25 days. SA-βgal levels decreased when the chondrocytes were transferred from the 2D to the 3D-TGP culture, with cells exhibiting a tissue-like growth until 42–45 days. Other senescence associated markers such as p16INK4a and p21 were also expressed only in 2D cultured cells but not in 3D-TGP tissue engineered cartilage. This is a first-of-its-kind report of a chemically synthesized and reproducible in vitro environment yielding an advantageous reversal of aging of human chondrocytes without any genomic modifications. The method is worth consideration as an optimal method for growing cells for regenerative medicine applications.

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