Search results for "M5"
showing 10 items of 192 documents
Activation of Muscarinic Receptors by Non-neuronal Acetylcholine
2011
The biological role of acetylcholine and the cholinergic system is revisited based particularly on scientific research early and late in the last century. On the one hand, acetylcholine represents the classical neurotransmitter, whereas on the other hand, acetylcholine and the pivotal components of the cholinergic system (high-affinity choline uptake, choline acetyltransferase and its end product acetylcholine, muscarinic and nicotinic receptors and esterase) are expressed by more or less all mammalian cells, i.e. by the majority of cells not innervated by neurons at all. Moreover, it has been demonstrated that acetylcholine and “cholinergic receptors” are expressed in non-neuronal organism…
First Nationwide Molecular Screening Program in Spain for Patients With Advanced Breast Cancer: Results From the AGATA SOLTI-1301 Study
2021
Anàlisi de seqüències d'ADN; Subtipus PAM50; Genètica molecular Análisis de secuencias de ADN; Subtipo PAM50; Genética molecular DNA sequence analyses; PAM50 subtype; Molecular genetic Background: The SOLTI-1301 AGATA study aimed to assess the feasibility of a multi-institutional molecular screening program to better characterize the genomic landscape of advanced breast cancer (ABC) and to facilitate patient access to matched-targeted therapies in Spain. Methods: DNA sequencing of 74 cancer-related genes was performed using FFPE tumor samples in three different laboratories with three different gene panels. A multidisciplinary advisory board prospectively recommended potential targeted trea…
Muscarinic acetylcholine receptor trafficking in streptolysin O-permeabilized MDCK cells.
1996
We investigated the validity of streptolysin O (SLO)-permeabilized Madin-Darbin canine kidney (MDCK) cells which express muscarinic acetylcholine receptors (mAChRs) coupled to pertussis toxin-sensitive guanine nucleotide-binding proteins (G proteins) for the study of the molecular machinery that regulated mAChR internalization and recycling. Exposure of SLO-permeabilized cells to carbachol-reduced cell surface receptor number by up to 40% without changing total receptor number. The kinetics and maximal extent of receptor internalization as well as the potency of carbachol to induce receptor internalization were almost identical in SLO-permeabilized and non-permeabilized cells. Using this se…
Murine embryonic stem cell line CGR8 expresses all subtypes of muscarinic receptors and multiple nicotinic receptor subunits: Down-regulation of α4- …
2015
Non-neuronal acetylcholine mediates its cellular effects via stimulation of the G-protein-coupled muscarinic receptors and the ligand-gated ion channel nicotinic receptors. The murine embryonic stem cell line CGR8 synthesizes and releases non-neuronal acetylcholine. In the present study a systematic investigation of the expression of nicotinic receptor subunits and muscarinic receptors was performed, when the stem cells were grown in the presence or absence of LIF, as the latter condition induces early differentiation. CGR8 cells expressed multiple nicotinic receptor subtypes (α3, α4, α7, α9, α10, β1, β2, β3, β4, γ, δ, e) and muscarinic receptors (M1, M3, M4, M5); M2 was detected only in 2 …
Acetylcholine release at motor endplates and autonomic neuroeffector junctions: a comparison.
1996
Acetylcholine released at motor endplates and at autonomic neuroeffector junctions binds to nicotinic and muscarinic receptors to affect the activity of the corresponding target cells. Additionally, nicotonic and muscarinic receptors modulate various intracellular regulatory pathways (second messengers, gene expression) and mediate trophic effects. To maintain homeostasis of the individual cell and of the whole organism the release of acetylcholine has to be strictly controlled within both nervous systems. The basic events of synthesis, storage, and release are comparable at motoneurones and autonomic neurones, but mechanisms regulating transmitter release appear to differ. The motor endpla…
Non-neuronal acetylcholine, a locally acting molecule, widely distributed in biological systems: expression and function in humans.
1998
Acetylcholine acts as a neurotransmitter in the central and peripheral nervous systems in humans. However, recent experiments demonstrate a widespread expression of the cholinergic system in non-neuronal cells in humans. The synthesizing enzyme choline acetyltransferase, the signalling molecule acetylcholine, and the respective receptors (nicotinic or muscarinic) are expressed in epithelial cells (human airways, alimentary tract, epidermis). Acetylcholine is also found in mesothelial, endothelial, glial, and circulating blood cells (platelets, mononuclear cells), as well as in alveolar macrophages. The existence of non-neuronal acetylcholine explains the widespread expression of muscarinic …
The Non-neuronal cholinergic system: an emerging drug target in the airways.
2001
The non-neuronal cholinergic system is widely expressed in human airways. Choline acetyltransferase (ChAT) and/or acetylcholine are demonstrated in more or less all epithelial surface cells (goblet cells, ciliated cells, basal cells), submucosal glands and airway smooth muscle fibres. Acetylcholine is also demonstrated in the effector cells of the immune system (lymphocytes, macrophages, mast cells). Epithelial, endothelial and immune cells express nicotinic and muscarinic receptors. Thus the cytomolecule acetylcholine can contribute to the regulation of basic cell functions via auto-/paracrine mechanisms (proliferation, differentiation, ciliary activity, secretion of water, ions and mucus,…
Small $C^1$ actions of semidirect products on compact manifolds
2020
Let $T$ be a compact fibered $3$--manifold, presented as a mapping torus of a compact, orientable surface $S$ with monodromy $\psi$, and let $M$ be a compact Riemannian manifold. Our main result is that if the induced action $\psi^*$ on $H^1(S,\mathbb{R})$ has no eigenvalues on the unit circle, then there exists a neighborhood $\mathcal U$ of the trivial action in the space of $C^1$ actions of $\pi_1(T)$ on $M$ such that any action in $\mathcal{U}$ is abelian. We will prove that the same result holds in the generality of an infinite cyclic extension of an arbitrary finitely generated group $H$, provided that the conjugation action of the cyclic group on $H^1(H,\mathbb{R})\neq 0$ has no eige…
The differential Galois group of the rational function field
2020
We determine the absolute differential Galois group of the field $\mathbb{C}(x)$ of rational functions: It is the free proalgebraic group on a set of cardinality $|\mathbb{C}|$. This solves a longstanding open problem posed by B.H. Matzat. For the proof we develop a new characterization of free proalgebraic groups in terms of split embedding problems, and we use patching techniques in order to solve a very general class of differential embedding problems. Our result about $\mathbb{C}(x)$ also applies to rational function fields over more general fields of coefficients.
A criterion for homeomorphism between closed Haken manifolds
2003
In this paper we consider two connected closed Haken manifolds denoted by M^3 and N^3, with the same Gromov simplicial volume. We give a simple homological criterion to decide when a given map f: M^3-->N^3 between M^3 and N^3 can be changed by a homotopy to a homeomorphism. We then give a convenient process for constructing maps between M^3 and N^3 satisfying the homological hypothesis of the map f.