Search results for " disease model"
showing 10 items of 39 documents
Abstract LB-085: A new role for LKB1 to regulate Heat Shock Protein 90 activity
2018
Abstract Approximately 30% of human non-small cell lung cancer (NSCLC) patients harbor a somatic KRAS mutation resulting, in aberrant activation of downstream signaling pathways that control cell proliferation, cell growth, and cell survival. Importantly, alleles of LKB1, a serine/threonine kinase that functions as a tumor suppressor, are somatically inactivated in ~30% of NSCLCs within KRAS-mutant NSCLC. The loss of LKB1 gives rise to aggressive, highly metastatic, and highly drug resistant tumors. We have previously demonstrated that the inactivation of the tumor suppressor lkb1 rendered mutant kras murine NSCLC resistant to targeted agents including BET bromodomain and kinase inhibitors.…
Virulent synergistic effect between Enterococcus faecalis and Escherichia coli assayed by using the Caenorhabditis elegans model.
2008
5 pages; International audience; BACKGROUND: The role of enterococci in the pathogenesis of polymicrobial infections is still debated. The purpose of this study was to evaluate the effect of virulent enterococci in the presence or absence of Escherichia coli strains in the in vivo Caenorhabditis elegans model. PRINCIPAL FINDINGS: This study demonstrated that there was a synergistic effect on virulence when an association of enterococci and E. coli (LT50 = 1.6 days+/-0.1 according to the tested strains and death of nematodes in 4 days+/-0.5) was tested in comparison with enterococci alone (LT50 = 4.6 days+/-0.1 and death in 10.4 days+/-0.6) or E. coli alone (LT50 = 2.1+/-0.9 and deaths 6.6+/…
Toxicity of ligand-dependent Cre recombinases and generation of a conditional Cre deleter mouse allowing mosaic recombination in peripheral tissues.
2007
Ligand-activated Cre recombinases are widely used for studying gene function in vitro and in conditional mouse models. To compare ligand-dependent Cre recombinases, different Cre estrogen receptor fusions were introduced into the ROSA26 locus of embryonic stem (ES) cells and assayed for genotoxicity and recombination efficiency. Of the tested recombinases, the CreERT2 variant showed no toxicity and was highly responsive to ligand induction. To constitutively express CreERT2 in mice and also to clarify whether the CreERT2 system displays background activity, we generated a knock-in mouse line harboring the CreERT2 coding region under the control of the ROSA26 locus. Analysis of this ROSA26-…
Janus -faced liposomes enhance antimicrobial innate immune response in Mycobacterium tuberculosis infection
2012
We have generated unique asymmetric liposomes with phosphatidylserine (PS) distributed at the outer membrane surface to resemble apoptotic bodies and phosphatidic acid (PA) at the inner layer as a strategy to enhance innate antimycobacterial activity in phagocytes while limiting the inflammatory response. Results show that these apoptotic body-like liposomes carrying PA (ABL/PA) ( i ) are more efficiently internalized by human macrophages than by nonprofessional phagocytes, ( ii ) induce cytosolic Ca 2+ influx, ( iii ) promote Ca 2+ -dependent maturation of phagolysosomes containing Mycobacterium tuberculosis (MTB), ( iv ) induce Ca 2+ -dependent reactive oxygen species (ROS) production, (…
miR-20b and miR-451a Are Involved in Gastric Carcinogenesis through the PI3K/AKT/mTOR Signaling Pathway: Data from Gastric Cancer Patients, Cell Line…
2020
Gastric cancer (GC) is one of the most common and lethal gastrointestinal malignancies worldwide. Many studies have shown that development of GC and other malignancies is mainly driven by alterations of cellular signaling pathways. MicroRNAs (miRNAs) are small noncoding molecules that function as tumor-suppressors or oncogenes, playing an essential role in a variety of fundamental biological processes. In order to understand the functional relevance of miRNA dysregulation, studies analyzing their target genes are of major importance. Here, we chose to analyze two miRNAs, miR-20b and miR-451a, shown to be deregulated in many different malignancies, including GC. Deregulated expression of miR…
CANDIDA ALBICANS INDUCES SELECTIVE DEVELOPMENT OF MACROPHAGES AND MONOCYTE DERIVED DENDRITIC CELLS BY A TLR2 DEPENDENT SIGNALLING
2011
As TLRs are expressed by haematopoietic stem and progenitor cells (HSPCs), these receptors may play a role in haematopoiesis in response to pathogens during infection. We have previously demonstrated that in in vitro defined conditions inactivated yeasts and hyphae of Candida albicans induce HSPCs proliferation and differentiation towards the myeloid lineage by a TLR2/MyD88 dependent pathway. In this work, we showed that C. albicans invasive infection with a low virulence strain results in a rapid expansion of HSPCs (identified as LKS cells: Lin(-) c-Kit(+) Sca-1(+) IL-7R alpha(-)), that reach the maximum at day 3 post-infection. This in vivo expansion of LKS cells in TLR2(-/-) mice was del…
Oral homeostasis disruption by medical plasticizer component bisphenol A in adult male rats.
2013
Objectives/Hypothesis Bisphenol A (BPA) is a synthetic estrogen-like chemical mimetic widely used in the manufacture of polycarbonate plastics and epoxy resins found in numerous consumer products including food packaging, medical devices, and dental sealants. Because it is recovered in fluids and it can reach high levels in saliva, this study aimed to evaluate its safety on oral homeostasis by examining its effects on salivary glands, mouth epithelium, water consumption, and salt preference, each parameter being estrogen sensitive. Study Design Randomized controlled trial involving rats. Methods A dose-response study was conducted in adult Wistar rats randomized into five groups (n = 12). B…
Neuroprotection by erythropoietin administration after experimental traumatic brain injury.
2007
A large body of evidence indicates that the hormone erythropoietin (EPO) exerts beneficial effects in the central nervous system (CNS). To date, EPO's effect has been assessed in several experimental models of brain and spinal cord injury. This study was conducted to validate whether treatment with recombinant human EPO (rHuEPO) would limit the extent of injury following experimental TBI. Experimental TBI was induced in rats by a cryogenic injury model. rHuEPO or placebo was injected intraperitoneally immediately after the injury and then every 8 h until 2 or 14 days. Forty-eight hours after injury brain water content, an indicator of brain edema, was measured with the wet-dry method and bl…
Detection of flap venous and arterial occlusion using interstitial glucose monitoring in a rodent model.
2010
Background: Free tissue transfer necessitates vigilant postoperative monitoring for vessel occlusion. Unfortunately, most monitoring methods require experienced personnel and are expensive to use. Furthermore, many tests have low sensitivity, low specificity, or significant delay between vessel occlusion and detection. The authors report on a novel method of tissue monitoring that avoids these limitations by tracking interstitial glucose concentration. Methods: Vertical rectus abdominis myocutaneous flaps were elevated in adult rats based on the superior epigastric vessels. Interstitial glucose within the flaps was monitored using a transcutaneous sensor. Interstitial glucose was recorded f…