Context: Designing efficient sensitive materials for the detection of volatile organic compounds (VOCs) such as ethanol, acetone, and benzene is stringent owing to the significant environmental and health risks induced by these compounds, in addition to their role as biomarkers for chronic diseases and food quality. This study investigates the adsorption mechanisms of VOC molecules (ethanol, acetone, and benzene) on both non-oxidized and oxidized SnO (110) monolayers and identifies the most suitable surface for gas sensing applications. For this, we examined structural properties, adsorption energies, density of states, gas responses, and recovery times.
View Article and Find Full Text PDFThe sensory cells that transduce the signals for hearing and balance are highly specialized mechanoreceptors called hair cells that together with supporting cells comprise the sensory epithelia of the inner ear. Loss of hair cells from toxin exposure and age can cause balance disorders and is essentially irreversible due to the inability of mammalian vestibular organs to regenerate physiologically active hair cells. Here, we show substantial regeneration of hair cells in a mouse model of vestibular damage by treatment with a combination of glycogen synthase kinase 3β and histone deacetylase inhibitors.
View Article and Find Full Text PDFThe conformational preferences of three azadipeptides Ac-Pro-azaXaa-NHMe [Xaa = Asn (1), Asp (2), Ala (3)] have been carried out in gas phase and solution (water) using the density functional method B3LYP/6-311 + + G(d,p) to explore the effect of the change of side chain of azaamino acids at the i + 2 position on the stability of these components. The most stable conformations of compounds (1), (2), and (3) have an amid bond oriented trans, trans, and cis, respectively, in gas phase, whereas the orientation of amid bond in water solvent of compounds (2) and (3) has changed to cis and trans, respectively. We have also noticed the importance of backbone-side chain hydrogen bonds in the stabilization of the β turn motif in gas phase since this motif is more stable in the case of compounds (1) and (2) and less stable in the case of compound (3) in which these hydrogen bonds are absent.
View Article and Find Full Text PDFWe analyzed transcriptomic data from otic sensory cells differentiated from human induced pluripotent stem cells (hiPSCs) by a previously described method to gain new insights into the early human otic neurosensory lineage. We identified genes and biological networks not previously described to occur in the human otic sensory developmental cell lineage. These analyses identified and ranked genes known to be part of the otic sensory lineage program (SIX1, EYA1, GATA3, etc.
View Article and Find Full Text PDFAuditory neuropathy is caused by the loss of afferent input to the brainstem via the components of the neural pathway comprising inner hair cells and the first order neurons of the spiral ganglion. Recent work has identified the synapse between cochlear primary afferent neurons and sensory hair cells as a particularly vulnerable component of this pathway. Loss of these synapses due to noise exposure or aging results in the pathology identified as hidden hearing loss, an initial stage of cochlear dysfunction that goes undetected in standard hearing tests.
View Article and Find Full Text PDFMost cases of sensorineural deafness are caused by degeneration of hair cells. Although stem/progenitor cell therapy is becoming a promising treatment strategy in a variety of organ systems, cell engraftment in the adult mammalian cochlea has not yet been demonstrated. In this study, we generated human otic progenitor cells (hOPCs) from induced pluripotent stem cells (iPSCs) in vitro and identified these cells by the expression of known otic markers.
View Article and Find Full Text PDFAge-related neurosensory deficit of the inner ear is mostly due to a loss of hair cells (HCs). Development of stem cell-based therapy requires a better understanding of factors and signals that drive stem cells into otic sensory progenitor cells (OSPCs) to replace lost HCs. Human induced pluripotent stem cells (hiPSCs) theoretically represent an unlimited supply for the generation of human OSPCs .
View Article and Find Full Text PDFThe inner ear represents a promising system to develop cell-based therapies from human induced pluripotent stem cells (hiPSCs). In the developing ear, Notch signaling plays multiple roles in otic region specification and for cell fate determination. Optimizing hiPSC induction for the generation of appropriate numbers of otic progenitors and derivatives, such as hair cells, may provide an unlimited supply of cells for research and cell-based therapy.
View Article and Find Full Text PDFStem cell-based therapies critically rely on selective cell migration toward pathological or injured areas. We previously demonstrated that human olfactory ectomesenchymal stem cells (OE-MSCs), derived from an adult olfactory lamina propria, migrate specifically toward an injured mouse hippocampus after transplantation in the cerebrospinal fluid and promote functional recoveries. However, the mechanisms controlling their recruitment and homing remain elusive.
View Article and Find Full Text PDFAngioedema is a rare but may be serious (laryngeal edema). This is a recurrent edema, subcutaneous and/or submucosal, whose cause is a hereditary or acquired deficiency in C1 inhibiteur (C1 inhibitor fraction of complement). We present the case of a 56 years old patient who showed recurrent episodes of swelling of the face and hands in association with chronic lymphocytic leukemia stage A.
View Article and Find Full Text PDFThe formation of ErbB2/ErbB3 heterodimers plays a critical role in ErbB2-mediated signaling in both normal mammary development and mammary tumor progression. Through 7 phosphoinositide 3-kinase (PI3K) phosphotyrosine-binding sites, ErbB3 is able to recruit PI3K and initiate the PI3K/AKT signaling pathway. To directly explore the importance of the ErbB3/PI3K pathway in mammary development and tumorigenesis, we generated a mouse model that carries a mutant ErbB3 allele lacking the seven known PI3K-binding sites (ErbB3(Δ85)).
View Article and Find Full Text PDFAn increase in the number of cases of cutaneous leishmaniasis has been observed, in recent years, in Morocco. We tried, through a series of 49 cases collected from the dermatology department at the military hospital Moulay Ismail of Meknes, to clarify the epidemiological, clinical and evolutionary aspects of the reported cases. We recorded for each patient: age, sex, geographic origin and the period before consultation.
View Article and Find Full Text PDFConsistent with their essential role in cell adhesion to the extracellular matrix, integrins and their associated signaling pathways have been shown to be involved in cell proliferation, migration, invasion and survival, processes required in both tumorigenesis and metastasis. β1-integrins represent the predominantly expressed integrins in mammary epithelial cells and have been proven crucial for mammary gland development and differentiation. Here we provide an overview of the studies that have used transgenic mouse models of mammary tumorigenesis to establish β1-integrin as a critical mediator of breast cancer progression and thereby as a potential therapeutic target for the development of new anticancer strategies.
View Article and Find Full Text PDFBackground: Visceral leishmaniasis is a notifiable parasitic disease that had increased in incidence in our region on the past few years. It is common in children. In adults, it occurs more on a background of immunodeficiency, and frequently with incomplete clinical manifestations, making the diagnosis complicated.
View Article and Find Full Text PDFObjectivesThe purpose of this retrospective study was to clarify the factors for a laboratory diagnosis of multiple myeloma (Kahler's disease) and assess their prognostic value.MethodsThe study of all 10 patients with multiple myeloma seen during 2009 in the department of internal medicine and the haematology laboratory of HASSAN II University Hospital Centre in Fez. Work-ups for all patients included hemograms, sedimentation speed, electrophoresis of serum and urinary proteins, myelograms, creatinemia, calcemia, ß2-microglobulin, LDH and CRP.
View Article and Find Full Text PDFThe Niemann Pick disease is a rare lysosomal storage disease responsible for numerous cytological abnormalities of blood cells and bone marrow. The diagnosis requires enzymatic dosages, which can be long and difficult. In this context, the detection of inconstant cytologic anomalies in blood and bone marrow smears, allowing a rapid screening, is an important step in the diagnostic approach.
View Article and Find Full Text PDFThe suppressor of translation initiation 4E-BP1 functions as a key regulator in cellular growth, differentiation, apoptosis and survival. While the control of 4E-BP1 activity via phosphorylation has been widely studied, the molecular mechanisms and the signaling pathways that govern 4E-BP1 gene expression are largely unknown. Here we show that inactivation of phosphatidylinositol 3-kinase (PI3K) consequent to stable expression of the antiproliferative somatostatin receptor 2 (sst2) in pancreatic cancer cells leads to transcriptional accumulation of the hypophosphorylated forms of 4E-BP1 protein.
View Article and Find Full Text PDFElevated expression and activation of the focal adhesion kinase (FAK) occurs in a large proportion of human breast cancers. Although several studies have implicated FAK as an important signaling molecule in cell culture systems, evidence supporting a role for FAK in mammary tumor progression is lacking. To directly assess the role of FAK in this process, we have used the Cre/loxP recombination system to disrupt FAK function in the mammary epithelium of a transgenic model of breast cancer.
View Article and Find Full Text PDFAims: In order to depict the fine interactions that lead to nodulation, absolute microbiological control of the symbiotic partners is required, i.e. the ability to obtain in vitro axenic nodulation, a condition that has never been fulfilled with the Casuarina-Frankia symbiosis.
View Article and Find Full Text PDFSince its discovery three decades ago as an inhibitor of GH release from the pituitary gland, somatostatin has attracted much attention because of its functional role in the regulation of a wide variety of physiological functions in the brain, pituitary, pancreas, gastrointestinal tract, adrenals, thyroid, kidney and immune system. Its actions include inhibition of endocrine and exocrine secretions, modulation of neurotransmission, motor and cognitive functions, inhibition of intestinal motility, absorption of nutrients and ions and vascular contractility. In addition, the peptide controls the proliferation of normal and tumor cells.
View Article and Find Full Text PDFVerticillium albo-atrum culture filtrates contain numerous metabolites such as enzymes and toxins. Their purification was carried out by high phase liquid chromatography (HPLC). In this study, we set out to look for other lighter metabolites that could be identified by gas chromatography coupled to mass spectrometry (GC-MS).
View Article and Find Full Text PDFBehcet syndrome is a systemic disease with venous tropism, generally expressed by thrombosis and phlebitis. Arterial involvement is more exceptional but can lead to aneurysm of the pulmonary artery, generally not more than three. We report a patient with Behcet syndrome who developed multiple aneurysms of the pulmonary artery and discuss the clinical, radiological aspects as well as the disease course and therapeutic management.
View Article and Find Full Text PDF