Search results for "Genetically Modified"

29 Elevated acetylcholine release in the hippocampus of transgenic mice expressing the human acetylcholinesterase

1998

Cytokine regulatory effects on α-1 proteinase inhibitor expression in NOD mouse islet endothelial cells

2002

Human microvascular islet endothelial cells (IEC) exhibit specific morphological and functional characteristics that differ from endothelia derived from other organs. One of these characteristics is the expression of alpha-1 proteinase inhibitor (Api). In this study, we observed its expression in nonobese diabetic (NOD) mouse IEC, in relation to the occurrence of type 1 diabetes and in response to cytokines, namely IL-1 beta and IL-10. In addition, IL-10-deficient NOD mice as well as IL-10 transgenic NODs were studied. Results have demonstrated that Api expression is: (i) highly specific for IEC in NOD mouse islets, as for humans; (ii) linked to the occurrence of early type 1 diabetes, and …

Naturally occurring autoantibodies interfere with β-amyloid metabolism and improve cognition in a transgenic mouse model of Alzheimer's disease 24 h …

2013

There is evidence that naturally occurring antibodies directed against Aβ (nAbs-Aβ) have a role in Aβ-metabolism and Aβ-clearance. The presence of nAbs-Aβ leads to a reduction in amyloid fibrillation and thus a reduction in their toxicity. We investigated the effects of nAbs-Aβ in respect to oligomerization and used the Tg2576 transgenic mouse model in order to investigate the rapid effect with a single-dose (24 h) on oligomer breakdown and cytokine secretion along with immunohistochemical characterization of synaptic plasticity. nAbs-Aβ were able to reduce toxic oligomer concentration with an increase in Aβ-monomers. Cytokine secretion was significantly reduced. Synaptic plasticity was als…

Cdc42 in osterix-expressing cells alters osteoblast behavior and myeloid lineage commitment

2021

Osteoblasts are not only responsible for bone formation. They also support hematopoiesis. This requires responding to cues originating from several signaling pathways, a task performed by Rho GTPases. We therefore examined several transgenic mouse models and used inhibitors of Cdc42 in vitro. Deletion of Cdc42 in vivo using the Osterix promoter suppressed osteoblast function, while its deletion in differentiating osteoblasts using the Collagen-a1(I) promoter decreased osteoblast numbers. In both cases, bone mineral density diminished confirming the importance of Cdc42. Evaluation of hematopoiesis revealed that deletion of Cdc42 using the Osterix, but not the Collagen-a1(I) promoter increase…

Fatal neuroinvasion and SARS-CoV-2 tropism in K18-hACE2 mice is partially independent on hACE2 expression

2022

ABSTRACTAnimal models recapitulating distinctive features of severe COVID-19 are critical to enhance our understanding of SARS-CoV-2 pathogenesis. Transgenic mice expressing human angiotensin-converting enzyme 2 (hACE2) under the cytokeratin 18 promoter (K18-hACE2) represent a lethal model of SARS-CoV-2 infection. The precise mechanisms of lethality in this mouse model remain unclear. Here, we evaluated the spatiotemporal dynamics of SARS-CoV-2 infection for up to 14 days post-infection. Despite infection and moderate pneumonia, rapid clinical decline or death of mice was invariably associated with viral neuroinvasion and direct neuronal injury (including brain and spinal neurons). Neuroinv…

Instability of Tandem Repetitive DNA in “Natural” and Transgenic Organisms

1996

Genome research of the last 10 years has forced us to re-evaluate our view of DNA as a relatively stable molecule. Unprecedented levels of DNA instability in germline and soma cells have been observed, associated primarily with tandem repetitive (tr) DNA sequences. We will discuss here briefly the structure and possible functions of trDNA in eukaryotes, the putative mechanisms of mutational change in repeat clusters and the evolutionary dimensions of trDNA instability (for other relevant reviews, sec Pardue and Hennig 1990; Vogt 1990; Charlesworth et al. 1994). A special focus will be on the behaviour of trDNA after DNA transfer experiments in transgenic organisms, with reference to our own…

Assessment of Genetically Modified Organisms (GMO) in Meat Products by PCR

2010

A simple DNA extraction method suitable for PCR detection of genetically modified maize.

2010

BACKGROUND: The polymerase chain reaction (PCR) is a powerful tool that is being increasingly used for detection of transgenic DNA. PCR requires only a minute quantity of template, but sensitive and accurate testing requires DNA of sufficient purity and free from inhibitors such as plant polysaccharides. Several standard protocols are available for this purpose, but they usually involve several steps, imply destruction of the maize kernel, or are time-consuming. Our aim was to develop a fast and simple extraction method to isolate a raw DNA-containing solution from maize tissues suitable for use as a template in a PCR-based detection assay with specific oligonucleotides directed to the iden…

A novel approach for the improvement of stress resistance in wine yeasts

2006

During wine production yeast cells are affected by several stress conditions that could affect their viability and fermentation efficiency. In this work we describe a novel genetic manipulation strategy designed to improve stress resistance in wine yeasts. This strategy involves modifying the expression of the transcription factor MSN2, which plays an important role in yeast stress responses. The promoter in one of the genomic copies of this gene has been replaced by the promoter of the SPI1 gene, encoding for a cell wall protein of unknown function. SPI1 is expressed at late phases of growth and is regulated by Msn2p. This modification allows self-induction of MSN2 expression. MSN2 gene tr…

Evaluation of different genetic procedures for the generation of artificial hybrids in Saccharomyces genus for winemaking

2012

Several methods based on recombinant DNA techniques have been proposed for yeast strain improvement; however, the most relevant oenological traits depend on a multitude of loci, making these techniques difficult to apply. In this way, hybridization techniques involving two complete genomes became interesting. Natural hybrid strains between different Saccharomyces species have been detected in diverse fermented beverages including wine, cider and beer. These hybrids seem to be better adapted to fluctuating situations typically observed in fermentations due to the acquisition of particular physiological properties of both parental strains. In this work we evaluated the usefulness of three dif…