Search results for "transporter"
showing 10 items of 676 documents
Sodium Fluxes and Astroglial Function
2012
Astrocytes exhibit their excitability based on variations in cytosolic Ca(2+) levels, which leads to variety of signalling events. Only recently, however, intracellular fluctuations of more abundant cation Na(+) are brought in the limelight of glial signalling. Indeed, astrocytes possess several plasmalemmal molecular entities that allow rapid transport of Na(+) across the plasma membrane: (1) ionotropic receptors, (2) canonical transient receptor potential cation channels, (3) neurotransmitter transporters and (4) sodium-calcium exchanger. Concerted action of these molecules in controlling cytosolic Na(+) may complement Ca(2+) signalling to provide basis for complex bidirectional astrocyte…
Functional characterization of protein variants of the human multidrug transporter ABCC2 by a novel targeted expression system in fibrosarcoma cells
2012
The multidrug resistance-associated protein 2 (MRP2/ABCC2) is involved in the efflux of endogenous and xenobiotic substrates, including several anticancer and antiviral drugs. The functional consequences of ABCC2 protein variants remain inconsistent, which may be due to shortcomings of the in vitro assays used. To study systematically the functional consequences of nonsynonymous ABCC2 variants, we used a novel “Screen and Insert” (ScIn) technology to achieve stable and highly reproducible expression of 13 ABCC2 variants in HT1080 cells. Western blotting revealed lower (30–65%) ABCC2 expression for D333G, R1174H, and R1181L as compared with wild type (WT; 100%), whereas the linked variant V1…
The MARA-LEB ion transport system
2020
Abstract A low-energy branch is under development for the MARA vacuum-mode recoil separator at the Accelerator Laboratory of the University of Jyvaskyla. This development will allow for the study of proton-rich nuclei through laser ionisation spectroscopy and mass measurements. After stopping and extraction from a buffer gas cell, the ions of interest will be accelerated and transported to dedicated experimental setups by an ion transport system consisting of several focusing, accelerating and mass-separating elements. This article presents the current design and simulations for the ion transport.
Arbuscular mycorrhiza - studies on the geosiphon symbiosis lead to the characterization of the first glomeromycotan sugar transporter
2007
Article Addendum ; International audience; The intimate arbuscular mycorrhiza (AM) association between roots and obligate symbiotic Glomeromycota (‘AM fungi’) ‘feeds’ about 80% of land plants. AM forming fungi supply land plants with inorganic nutrients and have an enormous impact on terrestrial ecosystems. In return, AM fungi obtain up to 20% of the plant‑fixed CO2, putatively as monosaccharides. In a recent work we have reported the characterization of the first glomeromycotan monosaccharide transporter, GpMST1, and its gene sequence. We discuss that AM fungi might take up sugars deriving from plant cell‑wall material. The GpMST1 sequence delivers valuable data for the isolation of orthol…
The loss of the inducible Aspergillus carbonarius MFS transporter MfsA leads to ochratoxin A overproduction
2014
Ochratoxin A (OTA), a nephrotoxic compound produced by certain Aspergillus and Penicillium species, is one of the most abundant mycotoxins in food commodities. Aspergillus carbonarius is the main source of OTA in wine, grape juice and dried vine fruits. Although many studies have focused on OTA production by A. carbonarius, little is known about the genes related to OTA production and transport. We have found a transporter that belongs to the major facilitator superfamily (MfsA) which is highly expressed with a 102-fold induction in an ochratoxigenic A. carbonarius strain compared to a low OTA producer strain. The encoding mfsA gene shows similarity to the multidrug efflux transporter flu1 …
A comprehensive review of the clinical utility of and a combined analysis of the clozapine/norclozapine ratio in therapeutic drug monitoring for adul…
2019
Introduction: This article comprehensively reviews the clinical utility of the serum clozapine/norclozapine (CLO/NCLO) ratio. Areas covered: Fifty-four published studies used this ratio (21 from a PubMed search from onset to 10/21/18 and 33 identified by the authors). To estimate a combined mean of the CLO/NCLO ratio in published studies, a PubMed search on 10/21/18 identified 422 articles leading to 19 included. The systematic review focused on 1) the combined analysis, 2) CYP1A2 activity, 3) clinical response, 4) cognition, and 5) renal function. Expert opinion: Our combined analysis provided a weighted mean CLO/NCLO ratio of 1.73 in 2,317 adult patients from 19 studies, but the range in …
Microregional expression of glucose transporter-1 and oxygenation status: lack of correlation in locally advanced cervical cancers.
2005
Abstract Purpose: Glucose transporter-1 (GLUT-1), a target gene of hypoxia-inducible factor-1, has been considered a candidate endogenous marker of tumor hypoxia. Expression of GLUT-1 may also serve as an indicator for the induction of the transcriptional response to hypoxia, which has been linked to enhanced proliferation, resistance to therapy, and metastatic propagation of cancer cells. Overexpression of GLUT-1 has been shown to correlate with poor prognosis in several tumor entities, among them cancers of the uterine cervix. The validity of these hypotheses is investigated. Experimental Design: The expression of GLUT-1 was assessed in 80 biopsies of Eppendorf oxygenation measurement tra…
Prognostic role of human equilibrative transporter 1 (hENT1) in patients with resected gastric cancer.
2010
Nucleoside transporter proteins are specialized proteins that mediate the transport of nucleosides and nucleoside analog drugs across the plasma membrane. The human equilibrative nucleoside transporter 1 (hENT1) is a member of these proteins and mediates cellular entry of gemcitabine, cytarabine, and fludarabine. The hENT1 expression has been demonstrated to be related with prognosis and activity of gemcitabine-based therapy in breast, ampullary, lung, and pancreatic cancer. We investigated the immunohistochemical expression of hENT in tumor samples from 111 patients with resected gastric adenocarcinoma, correlating these data with clinical parameters and disease outcomes. None of the patie…
Human equilibrative nucleoside transporter 1 (hENT1) levels predict response to gemcitabine in patients with biliary tract cancer (BTC)
2009
Background and aim: Translational data suggest that nucleoside transporters, in particular human equilibrative nucleoside transporter 1 (hENT1), play an important role in predicting clinical outcome after gemcitabine chemotherapy for several types of cancer. The aim of this study was to retrospectively determine patients' outcome according to the expression of hENT1 in tumoral cells of patients receiving gemcitabine-based therapy. Materials and Methods: The immunohistochemistry analysis was performed on samples from thirty-one patients with unresectable biliary tract cancer (BTC) consecutively treated with first line gemcitabine-based regimens. Results: Positive hENT1 staining patients were…
Personalized cancer medicine: from molecular diagnostics to targeted therapy with natural products.
2010
Personalized cancer medicine aims to develop individualized treatment options adapted to factors relevant for the prognosis of each patient. Molecular biomarkers are required to predict the likelihood of an individual tumor's responsiveness or of toxicity in normal organs and to advise optimized treatments with improved efficacy at reduced side effects for each cancer patient. In the present review, we present a concept, which takes advantage of methods of molecular diagnostics to identify predictive markers at the DNA, mRNA, and protein levels. Markers with prognostic value concerning treatment response and patient survival can then be used as targets to develop optimized drugs. We focus o…