Search results for "SIG"
showing 10 items of 19670 documents
Famotidine inhibits toll-like receptor 3-mediated inflammatory signaling in SARS-CoV-2 infection
2021
Apart from prevention using vaccinations, the management options for COVID-19 remain limited. In retrospective cohort studies, use of famotidine, a specific oral H2 receptor antagonist (antihistamine), has been associated with reduced risk of intubation and death in patients hospitalized with COVID-19. In a case series, nonhospitalized patients with COVID-19 experienced rapid symptom resolution after taking famotidine, but the molecular basis of these observations remains elusive. Here we show using biochemical, cellular, and functional assays that famotidine has no effect on viral replication or viral protease activity. However, famotidine can affect histamine-induced signaling processes i…
Synthesis and antiproliferative mechanism of action of pyrrolo[3′,2′:6,7] cyclohepta[1,2-d]pyrimidin-2-amines as singlet oxygen photosensitizers
2016
A new series of pyrrolo[3′,2′:6,7]cyclohepta[1,2-d]pyrimidin-2-amines, was conveniently prepared using a versatile and high yielding multistep sequence. A good number of derivatives was obtained and the cellular photocytotoxicity was evaluated in vitro against three different human tumor cell lines with EC50 (0.08–4.96 μM) values reaching the nanomolar level. Selected compounds were investigated by laser flash photolysis. The most photocytotoxic derivative, exhibiting a fairly long-lived triplet state (τ ∼ 7 μs) and absorbance in the UV–Vis, was tested in the photo-oxidations of 9,10-anthracenedipropionic acid (ADPA) by singlet oxygen. The photosentizing properties are responsible for the c…
Leukemia-associated activating mutation of Flt3 expands dendritic cells and alters T cell responses
2016
Lau et al. show that the FLT3-ITD mutation directly affects dendritic cell development in preleukemic mice, indirectly modulating T cell homeostasis and supporting the expansion of regulatory T cells.
Functional Gustatory Role of Chemoreceptors in Drosophila Wings
2016
Summary: Neuroanatomical evidence argues for the presence of taste sensilla in Drosophila wings; however, the taste physiology of insect wings remains hypothetical, and a comprehensive link to mechanical functions, such as flight, wing flapping, and grooming, is lacking. Our data show that the sensilla of the Drosophila anterior wing margin respond to both sweet and bitter molecules through an increase in cytosolic Ca2+ levels. Conversely, genetically modified flies presenting a wing-specific reduction in chemosensory cells show severe defects in both wing taste signaling and the exploratory guidance associated with chemodetection. In Drosophila, the chemodetection machinery includes mechan…
Drosophila Food-Associated Pheromones: Effect of Experience, Genotype and Antibiotics on Larval Behavior
2016
International audience; Animals ubiquitously use chemical signals to communicate many aspects of their social life. These chemical signals often consist of environmental cues mixed with species-specific signals-pheromones-emitted by conspecifics. During their life, insects can use pheromones to aggregate, disperse, choose a mate, or find the most suitable food source on which to lay eggs. Before pupariation, larvae of several Drosophila species migrate to food sources depending on their composition and the presence of pheromones. Some pheromones derive from microbiota gut activity and these food-associated cues can enhance larval attraction or repulsion. To explore the mechanisms underlying…
Efficient and reproducible experimental infections of rats with Blastocystis spp.
2018
Although Blastocystis spp. infect probably more than 1 billion people worldwide, their clinical significance is still controversial and their pathophysiology remains poorly understood. In this study, we describe a protocol for an efficient and reproducible model of chronic infection in rats, laying the groundwork for future work to evaluate the pathogenic potential of this parasite. In our experimental conditions, we were unable to infect rats using vacuolar forms of an axenically cultivated ST4 isolate, but we successfully established chronic infections of 4 week-old rats after oral administration of both ST3 and ST4 purified cysts isolated from human stool samples. The infection protocol …
Redox modulation of muscle mass and function
2020
Muscle mass and strength are very important for exercise performance. Training-induced musculoskeletal injuries usually require periods of complete immobilization to prevent any muscle contraction of the affected muscle groups. Disuse muscle wasting will likely affect every sport practitioner in his or her lifetime. Even short periods of disuse results in significant declines in muscle size, fiber cross sectional area, and strength. To understand the molecular signaling pathways involved in disuse muscle atrophy is of the utmost importance to develop more effective countermeasures in sport science research. We have divided our review in four different sections. In the first one we discuss t…
Ca2+ signalling plays a role in celastrol‐mediated suppression of synovial fibroblasts of rheumatoid arthritis patients and experimental arthritis in…
2019
Background and purpose Celastrol exhibits anti-arthritic effects in rheumatoid arthritis (RA), but the role of celastrol-mediated Ca2+ mobilization in treatment of RA remains undefined. Here, we describe a regulatory role for celastrol-induced Ca2+ signalling in synovial fibroblasts of RA patients and adjuvant-induced arthritis (AIA) in rats. Experimental approach We used computational docking, Ca2+ dynamics and functional assays to study the sarcoplasmic/endoplasmic reticulum Ca2+ ATPase pump (SERCA). In rheumatoid arthritis synovial fibroblasts (RASFs)/rheumatoid arthritis fibroblast-like synoviocytes (RAFLS), mechanisms of Ca2+ -mediated autophagy were analysed by histological, immunohis…
Ferritin and C-reactive protein are predictive biomarkers of mortality and macrophage activation syndrome in adult onset Still's disease. Analysis of…
2020
ObjectiveTo assess the predictive role of ferritin and C-reactive protein (CRP) on occurrence of macrophage activation syndrome (MAS) and mortality in patients with adult onset Still's disease (AOSD), a rare and severe disease, included in the multicentre Gruppo Italiano di Ricerca in Reumatologia Clinica e Sperimentale (GIRRCS) cohort.MethodsThe predictive role, at the time of diagnosis, of serum levels of ferritin and CRP on occurrence of MAS and mortality, was evaluated by logistic regression analyses and receiver-operating characteristic (ROC) curves were built to identify patients at high risk of MAS and mortality, respectively.ResultsIn assessed 147 patients with AOSD, levels of ferri…
Proteomics Reveals the Potential Protective Mechanism of Hydrogen Sulfide on Retinal Ganglion Cells in an Ischemia/Reperfusion Injury Animal Model
2020
Glaucoma is the leading cause of irreversible blindness and is characterized by progressive retinal ganglion cell (RGC) degeneration. Hydrogen sulfide (H2S) is a potent neurotransmitter and has been proven to protect RGCs against glaucomatous injury in vitro and in vivo. This study is to provide an overall insight of H2S&rsquo