Search results for "Processes"
showing 10 items of 3831 documents
Mitochondrial Changes in β0-Thalassemia/Hb E Disease.
2015
The compound β°-thalassemia/Hb E hemoglobinopathy is characterized by an unusually large range of presentation from essentially asymptomatic to a severe transfusion dependent state. While a number of factors are known that moderate presentation, these factors do not account for the full spectrum of presentation. Mitochondria are subcellular organelles that are pivotal in a number of cellular processes including oxidative phosphorylation and apoptosis. A mitochondrial protein enriched proteome was determined and validated from erythroblasts from normal controls and β°-thalassemia/Hb E patients of different severities. Mitochondria were evaluated through the use of mitotracker staining, analy…
Odorant metabolizing enzymes in the peripheral olfactory process
2016
Odorant metabolizing enzymes in the peripheral olfactory process
Apoptotic Activity of MeCP2 Is Enhanced by C-Terminal Truncating Mutations.
2016
Methyl-CpG binding protein 2 (MeCP2) is a widely abundant, multifunctional protein most highly expressed in post-mitotic neurons. Mutations causing Rett syndrome and related neurodevelopmental disorders have been identified along the entire MECP2 locus, but symptoms vary depending on mutation type and location. C-terminal mutations are prevalent, but little is known about the function of the MeCP2 C-terminus. We employ the genetic efficiency of Drosophila to provide evidence that expression of p.Arg294* (more commonly identified as R294X), a human MECP2 E2 mutant allele causing truncation of the C-terminal domains, promotes apoptosis of identified neurons in vivo. We confirm this novel find…
Coordination of the biliverdin D-ring in bacteriophytochromes.
2018
Phytochrome proteins translate light into biochemical signals in plants, fungi and microorganisms. Light cues are absorbed by a bilin chromophore, leading to an isomerization and a rotation of the D-ring. This relays the signal to the protein matrix. A set of amino acids, which is conserved across the phytochrome superfamily, holds the chromophore in the binding pocket. However, the functional role of many of these amino acids is not yet understood. Here, we investigate the hydrogen bonding network which surrounds the D-ring of the chromophore in the resting (Pr) state. We use UV/vis spectroscopy, infrared absorption spectroscopy and X-ray crystallography to compare the photosensory domains…
Extracellular non-coding RNA signatures of the metacestode stage of Echinococcus multilocularis
2020
Extracellular RNAs (ex-RNAs) are secreted by cells through different means that may involve association with proteins, lipoproteins or extracellular vesicles (EV). In the context of parasitism, ex-RNAs represent new and exciting communication intermediaries with promising potential as novel biomarkers. In the last years, it was shown that helminth parasites secrete ex-RNAs, however, most work mainly focused on RNA secretion mediated by EV. Ex-RNA study is of special interest in those helminth infections that still lack biomarkers for early and/or follow-up diagnosis, such as echinococcosis, a neglected zoonotic disease caused by cestodes of the genus Echinococcus. In this work, we have char…
Levosimendan protects human hepatocytes from ischemia-reperfusion injury.
2017
Background Ischemia-reperfusion injury (IRI) is a major challenge in liver transplantation. The mitochondrial pathway plays a pivotal role in hepatic IRI. Levosimendan, a calcium channel sensitizer, was shown to attenuate apoptosis after IRI in animal livers. The aim of this study was to investigate the effect of levosimendan on apoptosis in human hepatocytes. Methods Primary human hepatocytes were either exposed to hypoxia or cultured under normoxic conditions. After the hypoxic phase, reoxygenation was implemented and cells were treated with different concentrations of levosimendan (10ng/ml, 100ng/ml, 1000ng/ml). The overall metabolic activity of the cells was measured using 3-(4,5-dimeth…
Odour perception: A review of an intricate signalling pathway
2015
The perception of odours is the result of the complex processing of a signal, which initiates at peripheral receptors and ends in the brain. Along this pathway, olfactory signal processing proceeds through several steps; each step possesses its own complexity, and all steps are also intricately connected. This review aims to describe the main intricate steps of olfactory processing in mammals, some of which remain unclear, and the close associations and overlapping nature of these steps. The causes of both the complexity and the variability of olfactory signals are examined: the nature of olfactory receptors, involving the diversity of the genome; the spatial organization of the olfactory e…
Afferent and Efferent Connections of the Cortex-Amygdala Transition Zone in Mice
2016
The transitional zone between the ventral part of the piriform cortex and the anterior cortical nucleus of the amygdala, named the cortex-amygdala transition zone (CxA), shows two differential features that allow its identification as a particular structure. First, it receives dense cholinergic and dopaminergic innervations as compared to the adjacent piriform cortex and amygdala, and second, it receives projections from the main and accessory olfactory bulbs. In this work we have studied the pattern of afferent and efferent projections of the CxA, which are mainly unknown, by using the retrograde tracer Fluorogold and the anterograde tracer biotinylated dextranamine. The results show that …
Stimulus Driven Functional Transformations in the Early Olfactory System.
2021
Olfactory stimuli are encountered across a wide range of odor concentrations in natural environments. Defining the neural computations that support concentration invariant odor perception, odor discrimination, and odor-background segmentation across a wide range of stimulus intensities remains an open question in the field. In principle, adaptation could allow the olfactory system to adjust sensory representations to the current stimulus conditions, a well-known process in other sensory systems. However, surprisingly little is known about how adaptation changes olfactory representations and affects perception. Here we review the current understanding of how adaptation impacts processing in …
Intermittent targeted therapies and stochastic evolution in patients affected by chronic myeloid leukemia
2016
Front line therapy for the treatment of patients affected by chronic myeloid leukemia (CML) is based on the administration of tyrosine kinase inhibitors, namely imatinib or, more recently, axitinib. Although imatinib is highly effective and represents an example of a successful molecular targeted therapy, the appearance of resistance is observed in a proportion of patients, especially those in advanced stages. In this work, we investigate the appearance of resistance in patients affected by CML, by modeling the evolutionary dynamics of cancerous cell populations in a simulated patient treated by an intermittent targeted therapy. We simulate, with the Monte Carlo method, the stochastic evolu…