Search results for "Receptor"
showing 10 items of 6990 documents
Functional analysis of broadly tuned odorant receptors expressed in the mouse septal organ through patch-clamp recordings in an intact preparation an…
2010
The septal organ (SO) is a small island of olfactory epithelium located at the ventral base of the nasal septum. SO neurons express identified odorant receptors, but its function remains unknown. Using perforated patch clamp recordings, we investigated the response properties of SO neurons in the intact epithelium of mice to a panel of 45 odorants or mixtures. Out of 328 neurons tested, approximately 70% responded to odor stimulation. Among the responsive neurons, 72.5 % responded to multiple odorants. Responding neurons were tested with increasing concentrations of 3 odorants (octanoic acid, (+) camphor, amylacetate) and a mixture (fox urine). Dose-response curves show nanomolar threshold …
Système olfactif et neurobiologie
2006
Les connaissances neurobiologiques sur l’odorat progressent désormais rapidement depuis la découverte des récepteurs des odorants, remarquables par leur grand nombre et leur diversité. Des réponses sont maintenant apportées aux questions posées par les propriétés originales de la perception olfactive dont beaucoup sont déterminées dès le niveau de l’organe olfactif, et sont fortement déterminées par la génétique. Les connaissances génétiques sur les récepteurs dévoilent une considérable réduction du nombre de gènes olfactifs fonctionnels dans l’espèce humaine et alimentent une réflexion sur l’évolution de l’odorat. Autre avancée riche de promesses : l’application à l’olfaction des méthodes …
Speciation of dimethyltin(IV) – and trimethyltin(IV) – carbocysteinate and – glutamate systems in aqueous media
2008
The formation of complex species in the dimethyltin(IV) and trimethyltin(IV)-carboxymethyl-L-cysteinate (carbocysteinate) systems in NaClaq, at different ionic strengths, and in a multicomponent Na+, K+, Ca2+, Mg2+, Cl- and SO42- medium representative of the seawater major composition, is discussed. Experimental results give evidence for the formation of the following species (L¼carbocysteinate): [(CH3)2Sn(L)]0, [(CH3)2Sn(HL)]+, [(CH3)2Sn(OH)(L)]-, [(CH3)2Sn(OH)2(L)]2- in the DMT–CCYS system, and [(CH3)3Sn(HL)]0, [(CH3)3Sn(L)]- and [(CH3)3Sn(OH)(L)]2- in the TMT-CCYS system. The ionic strength dependence of formation constants was taken into account by an extended Debye Huckel type equation…
Sex steroid hormone receptors, their ligands, and nuclear and non-nuclear pathways
2015
The ability of a cell to respond to a particular hormone depends on the presence of specific receptors for those hormones. Once the hormone has bound to its receptor, and following structural and biochemical modifications to the receptor, it separates from cytoplasmic chaperone proteins, thereby exposing the nuclear localization sequences that result in the activation of the receptor and initiation of the biological actions of the hormone on the target cell. In addition, recent work has demonstrated new pathways of steroid signaling through orphan and cell surface receptors that contribute to more rapid, “non-nuclear” or non-transcriptional effects of steroid hormones, often involving G-pro…
Sigma 1 receptora ietekme uz peļu mezenhimālo stromas šūnu osteodiferenciāciju
2021
Mezenhimālajām stromas šūnām (MSŠ) piemīt osteodiferenciācijas potenciāls. Sigma-1 receptors (SigmaR1) ir transmembrānu proteīns, tā ietekme uz osteodiferenciāciju nav vēl zināma. Bakalaura darba mērķis bija noskaidrot SigmaR1 ietekmi uz peļu taukaudu MSŠ (T-MSŠ) osteodiferenciāciju. Osteodiferenciācijas norise un SigmaR1 ietekme uz osteodiferenciāciju tika analizēta, pētot osteoģenēzē iesaistīto gēnu ekspresiju peļu T-MSŠ ar qPCR metodi. Salīdzinot izslēgta SigmaR1 (S1R-/-) T-MSŠ pret WT (wild type) T-MSŠ gēnu ekspresiju pēc osteodiferenciācijas, transkripcijas faktora osterix ekspresija tika nozīmīgi palielināta, bet nediferencētā stāvoklī būtiskas izmaiņas netika novērotas.
A novel intrinsically disordered outer membrane lipoprotein ofAggregatibacter actinomycetemcomitansbinds various cytokines and plays a role in biofil…
2017
Intrinsically disordered proteins (IDPs) do not have a well-defined and stable 3-dimensional fold. Some IDPs can function as either transient or permanent binders of other proteins and may interact with an array of ligands by adopting different conformations. A novel outer membrane lipoprotein, bacterial interleukin receptor I (BilRI) of the opportunistic oral pathogen Aggregatibacter actinomycetemcomitans binds a key gatekeeper proinflammatory cytokine interleukin (IL)-1b. Because the amino acid sequence of the novel lipoprotein resembles that of fibrinogen binder A of Haemophilus ducreyi, BilRI could have the potential to bind other proteins, such as host matrix proteins. However, from th…
Increased dosage of Ink4/Arf protects against glucose intolerance and insulin resistance associated with aging
2013
Recent genome-wide association studies have linked type-2 diabetes mellitus to a genomic region in chromosome 9p21 near the Ink4/Arf locus, which encodes tumor suppressors that are up-regulated in a variety of mammalian organs during aging. However, it is unclear whether the susceptibility to type-2 diabetes is associated with altered expression of the Ink4/Arf locus. In the present study, we investigated the role of Ink4/Arf in age-dependent alterations of insulin and glucose homeostasis using Super-Ink4/Arf mice which bear an extra copy of the entire Ink4/Arf locus. We find that, in contrast to age-matched wild-type controls, Super-Ink4/Arf mice do not develop glucose intolerance with agi…
Activation of the p38MAPK cascade is associated with upregulation of TNF alpha receptors in the spinal motor neurons of mouse models of familial ALS.
2005
Phosphorylated p38 mitogen-activated protein kinase (p38MAPK), but not activated c-jun-N-terminal kinase (JNK), increases in the motor neurons of transgenic mice overexpressing ALS-linked SOD1 mutants at different stages of the disease. This effect is associated with a selective increase of phosphorylated MKK3-6, MKK4 and ASK1 and a concomitant upregulation of the TNFalpha receptors (TNFR1 and TNFR2), but not IL1beta and Fas receptors. Activation of both p38 MAPK and JNK occurs in the activated microglial cells of SOD1 mutant mice at the advanced stage of the disease; however, this effect is not accompanied by the concomitant activation of the upstream kinases ASK1 and MKK3,4,6, while both …
Influence of aryl hydrocarbon- (Ah) receptor and genotoxins on DNA repair gene expression and cell survival of mouse hepatoma cells
2009
The aryl hydrocarbon receptor (AhR) mediates toxicity of a variety of environmental pollutants such as polycyclic aromatic hydrocarbons (PAHs) and dioxins. However, the underlying mechanisms and genetic programmes regulated by AhR to cause adverse effects but also to counteract poisoning are still poorly understood. Here we analysed the effects of two AhR ligands, benzo[a]pyrene (B[a]P), a DNA damaging tumour initiator and promotor and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a pure tumour promoter, on cell survival and on nucleotide excision repair (NER) gene expression. NER deals with so called "bulky" DNA adducts including those generated by enzymatically activated B[a]P. Therefore, t…
Predictive value of p53, Ki67 and TLR5 in neoplastic progression of Barrett’s esophagus: a matched case–control study
2022
Abstract Barrett’s esophagus progresses to high-grade dysplasia or cancer along the well-established metaplasia-dysplasia-adenocarcinoma sequence. The aim of this study was to evaluate the value of p53, Ki67, and toll-like receptor 5 (TLR5) in prediction of malignant progression of Barrett’s metaplasia and low-grade dysplasia. This was a retrospective matched case–control study based on Northern and Central Finland population. Patients diagnosed with esophageal high-grade dysplasia or adenocarcinoma were included. From these patients, all previous endoscopy samples were obtained along with original diagnostic HE-slides and clinical data. Age- and sex-matched patients with non-progressing Ba…