Search results for "Techniques"
showing 10 items of 4426 documents
Innovations in assisted reproductive technologies: impact on contemporary donor egg practice and future advances.
2018
Innovations in assisted reproductive technologies (ART) have driven progress in the donor egg field since the birth of the first baby derived from a donor egg in 1983. Over time, donor oocytes have become an increasingly used option for patients unable to conceive with autologous oocytes. In donor egg, the unique separation of the oocyte source and recipient uterus has created a model that has propelled advances in ART. Progressive ART innovations that have optimized the oocyte donor and resulting embryo include the following: evaluation of ovarian reserve, controlled ovarian hyperstimulation regimens that reduce the risk of ovarian hyperstimulation syndrome, blastocyst culture, oocyte cryo…
Progressive Characterization of Visual Phenotype in Bardet-Biedl Syndrome Mutant Mice
2019
Purpose Bardet-Biedl syndrome (BBS) is an archetypical ciliopathy caused by defective ciliary trafficking and consequent function. Insights gained from BBS mouse models are applicable to other syndromic and nonsyndromic retinal diseases. This progressive characterization of the visual phenotype in three BBS mouse models sets a baseline for testing therapeutic interventions. Methods Longitudinal acquisition of electroretinograms, optical coherence tomography scans, and visual acuity using the optomotor reflex in Bbs6/Mkks, Bbs8/Ttc8, and Bbs5 knockout mice. Gene and protein expression analysis in vivo and in vitro. Results Complete loss of BBS5, BBS6, or BBS8 leads to different rates of reti…
Usherin defects lead to early-onset retinal dysfunction in zebrafish
2018
Mutations in USH2A are the most frequent cause of Usher syndrome and autosomal recessive nonsyndromic retinitis pigmentosa. To unravel the pathogenic mechanisms underlying USH2A-associated retinal degeneration and to evaluate future therapeutic strategies that could potentially halt the progression of this devastating disorder, an animal model is needed. The available Ush2a knock-out mouse model does not mimic the human phenotype, because it presents with only a mild and late-onset retinal degeneration. Using CRISPR/Cas9-technology, we introduced protein-truncating germline lesions into the zebrafish ush2a gene (ush2a(rmc1): c.2337_2342delinsAC; p.Cys780GlnfsTer32 and ush2a(b1245): c.15520_…
Generation of an inducible RPE-specific Cre transgenic-mouse line.
2018
The retinal pigment epithelium (RPE) is an epithelial monolayer in the back of the vertebrate eye. RPE dysfunction is associated with retinal degeneration and blindness. In order to fully understand how dysregulation affects visual function, RPE-specific gene knockouts are indispensable. Since the currently available RPE-specific Cre recombinases show lack of specificity or poor recombination, we sought to generate an alternative. We generated a tamoxifen-inducible RPE-specific Cre transgenic mouse line under transcriptional control of an RPE-specific Tyrosinase enhancer. We characterized the Cre-mediated recombinant expression by crossing our RPE-Tyrosinase-CreErT2 mouse line with the tdTo…
Quantitative characterization of translational riboregulators using an in vitro transcription–translation system
2018
Riboregulators are short RNA sequences that, upon binding to a ligand, change their secondary structure and influence the expression rate of a downstream gene. They constitute an attractive alternative to transcription factors for building synthetic gene regulatory networks because they can be engineered de novo. However, riboregulators are generally designed in silico and tested in vivo, which provides little quantitative information about their performances, thus hindering the improvement of design algorithms. Here we show that a cell-free transcription-translation (TX-TL) system provides valuable information about the performances of in silico designed riboregulators. We first propose a …
Oxidative stress, glutathione, and gene expression as key indicators in SH-SY5Y cells exposed to zearalenone metabolites and beauvericin.
2020
The co-presence of mycotoxins from fungi of the genus Fusarium is a common fact in raw food and food products, as trace levels of them or their metabolites can be detected, unless safety practices during manufacturing are carried out. Zearalenone (ZEA), its metabolites α-zearalenol (α-ZEL) and β-zearalenol (β-ZEL) and, beauvericin (BEA) are co/present in cereals, fruits or their products which is a mixture that consumer are exposed and never evaluated in neuronal cells. In this study the role of oxidative stress and intracellular defense systems was assessed by evaluating reactive oxygen species (ROS) generation and glutathione (GSH) ratio activity in a human neuroblastoma cell line, SH-SY5…
The membrane-associated MUC1 improves adhesion of salivary MUC5B on buccal cells. Application to development of an in vitro cellular model of oral ep…
2015
Objectives: The mucosal pellicle is a thin layer of salivary proteins, mostly MUC5B mucins, anchored to epithelial oral cells. This pellicle is involved in protection of oral mucosae against abrasion, pathogenic microorganisms or chemical xenobiotics. The present study aimed at studying the involvement of MUC1 in mucosal pellicle formation and more specifically in salivary MUC5B binding using a cell-based model of oral epithelium. DESIGN: MUC1 mRNAs were not detected in TR146 cells, and therefore a stable cell line named TR146/MUC1 expressing this protein was developed by transfection. TR146 and TR146/MUC1 were incubated with human saliva in order to evaluate retention of MUC5B by epithelia…
mcr-1- like detection in commensal Escherichia coli and Salmonella spp. from food-producing animals at slaughter in Europe
2017
International audience; We evaluate here the presence of the mcr-1-like and mcr-2 genes in Escherichia coli and Salmonella spp. isolated from healthy food-producing animals at slaughter between 2002 and 2014 in Europe. Isolates were retrieved from cattle, pig and chicken from 11 European countries of production. The susceptibility to colistin and antibiotics used in human medicine was determined by agar dilution. Colistin-resistant isolates were PCR-screened for mcr genes. mcr-positive isolates were typed by Pulsed-Field Gel Electrophoresis (PFGE) and Multi-Locus Sequence Typing. Among the 10,206 E. coli and 1774 Salmonella spp. isolated from cattle, pigs and chickens, 148 E. coli and 92 Sa…
The development of a tissue-engineered tracheobronchial epithelial model using a bilayered collagen-hyaluronate scaffold
2016
Today, chronic respiratory disease is one of the leading causes of mortality globally. Epithelial dysfunction can play a central role in its pathophysiology. The development of physiologically-representative in vitro model systems using tissue-engineered constructs might improve our understanding of epithelial tissue and disease. This study sought to engineer a bilayered collagen-hyaluronate (CHyA-B) scaffold for the development of a physiologically-representative 3D in vitro tracheobronchial epithelial co-culture model. CHyA-B scaffolds were fabricated by integrating a thin film top-layer into a porous sub-layer with lyophilisation. The film layer firmly connected to the sub-layer with del…
Salmon fibrinogen and chitosan scaffold for tissue engineering: in vitro and in vivo evaluation
2018
3D fibrous scaffolds have received much recent attention in regenerative medicine. Use of fibrous scaffolds has shown promising results in tissue engineering and wound healing. Here we report the development and properties of a novel fibrous scaffold that is useful for promoting wound healing. A scaffold made of salmon fibrinogen and chitosan is produced by electrospinning, resulting in a biocompatible material mimicking the structure of the native extracellular matrix (ECM) with suitable biochemical and mechanical properties. The scaffold is produced without the need for enzymes, in particular thrombin, but is fully compatible with their addition if needed. Human dermal fibroblasts culture…