Search results for "TP"
showing 10 items of 4688 documents
Alkamides from Echinacea angustifolia Interact with P-Glycoprotein of Primary Brain Capillary Endothelial Cells Isolated from Porcine Brain Blood Ves…
2013
The blood-brain barrier prevents the passage of toxic compounds from blood circulation into brain tissue. Unfortunately, drugs for the treatment of neurodegenerative diseases, brain tumors, and other diseases also do not cross the blood-brain barrier. In the present investigation, we used isolated porcine brain capillary endothelial cells and a flow cytometric calcein-AM assay to analyze inhibition of P-glycoprotein, a major constituent of the blood-brain barrier. We tested 8 alkamides isolated from Echinacea angustifolia and found that four of them inhibited P-glycoprotein-mediated calcein transport in porcine brain capillary endothelial cells.
Cytotoxicity of the indole alkaloid reserpine from Rauwolfia serpentina against drug-resistant tumor cells.
2015
Abstract Background: The antihypertensive reserpine is an indole alkaloid from Rauwolfia serpentina and exerts also profound activity against cancer cells in vitro and in vivo. The present investigation was undertaken to investigate possible modes of action to explain its activity toward drug-resistant tumor cells. Material and methods: Sensitive and drug-resistant tumor cell lines overexpressing P-glycoprotein (ABCB1/MDR1), breast cancer resistance protein (ABCG2/BCRP), mutation-activated epidermal growth factor receptor (EGFR), wild-type and p53-knockout cells as well as the NCI panel of cell lines from different tumor origin were analyzed. Reserpine's cytotoxicity was investigated by res…
Selective downregulation of the MDR1 gene product in Caco-2 cells by stable transfection to prove its relevance in secretory drug transport.
2005
Considerable interest is focused on overcoming multidrug resistance (MDR) in cancer chemotherapy. The in vitro experiments to characterize P-glycoprotein's (P-gp) function and to decrease its effects have led to a variety of strategies such as addition of competitors or supplementation of the medium with oligonucleotides complementary to the 5'-end of the MDR1-mRNA. For the Caco-2 cell line, an in vitro model for absorption screening, expressing multiple transporters including P-gp, which pumps substances back into the apical solution, P-gp activity might mask other relevant transport proteins' activity. The objective of the present study was to construct a Caco-2 subline with reduced P-gp …
Pharmacogenomic Characterization of Cytotoxic Compounds from Salvia officinalis in Cancer Cells.
2015
Salvia officinalis is used as a dietary supplement with diverse medicinal activity (e.g. antidiabetic and antiatherosclerotic effects). The plant also exerts profound cytotoxicity toward cancer cells. Here, we investigated possible modes of action to explain its activity toward drug-resistant tumor cells. Log10IC50 values of two constituents of S. officinalis (ursolic acid, pomolic acid) were correlated to the expression of ATP-binding cassette (ABC) transporters (P-glycoprotein/ABCB1/MDR1, MRP1/ABCC1, BCRP/ABCG2) and epidermal growth factor receptor (EGFR) or mutations in RAS oncogenes and the tumor suppressor gene TP53 of the NCI panel of cell lines. Gene expression profiles predicting se…
Analytical Performance Issues
2014
Contaminated hospital surfaces have been demonstrated to be an important environmental reservoir of microorganisms that can increase the risk of nosocomial infection in exposed patients. As a consequence, cleaning and disinfecting hospital environments play an important role among strategies for preventing healthcare-associated colonization and infections. The aim of the present study was to evaluate whether adenosine triphosphate (ATP) presence, measured by bioluminescence methods, can predict microbiological contamination of hospital surfaces. The study was carried out between September and December 2012 at the University Hospital "P. Giaccone" of Palermo. A total of 193 randomly selected…
Partial substitution of fish meal with vegetable protein sources in a diet for sea bass: effects on lipogenesis
2005
Three isoproteic (49.4%) and isolipidic (17.0%) diets were prepared: A control diet FM, in which protein was derived from fish meal and two experimental diets in which 70% of the fish meal protein was substituted with wheat gluten meal (WGM) or wheat gluten meal plus soybean meal (WGMsb), respectively. The essential limiting amino acids were added to satisfy the requirements of the species (Tibaldi et al., 1996). Three hundred and fifteen sea bass (initial weight = 23.9±0. 1g )were randomly divided into nine homogenous groups. The animals were reared in a closed recirculation system at 23.9 ◦ C and were fed ad libitum twice a day for 96 days. The fish were weighed at the beginning and the e…
Clinical evaluation of bempedoic acid for the treatment of hyperlipidaemia.
2021
Bempedoic acid (BA) is a novel first-in-class oral lipid-lowering therapy. BA has been approved by the European Medicinal Agency and Food and Drug Administration and has been commercialised throughout Europe since the end of 2020 as an add-on therapy in patients at high/very-high cardiovascular risk that are not at LDL-C goals with current lipid-lowering treatments. Recently, Italian lipid management experts gathered to discuss several open questions on BA characteristics and BArelated practical clinical issues. The panel permitted collection of its opinions in a ten Q&A format. Aim: The aim of this viewpoint is to discuss and answer several open questions on BA characteristics and BA-r…
CitA/CitB Two-Component System Regulating Citrate Fermentation in Escherichia coli and Its Relation to the DcuS/DcuR System In Vivo
2011
ABSTRACT Citrate fermentation by Escherichia coli requires the function of the citrate/succinate antiporter CitT ( citT gene) and of citrate lyase ( citCDEFXG genes). Earlier experiments suggested that the two-component system CitA/CitB, consisting of the membrane-bound sensor kinase CitA and the response regulator CitB, stimulates the expression of the genes in the presence of citrate, similarly to CitA/CitB of Klebsiella pneumoniae . In this study, the expression of a chromosomal citC-lacZ gene fusion was shown to depend on CitA/CitB and citrate. CitA/CitB is related to the DcuS/DcuR two-component system which induces the expression of genes for fumarate respiration in response to C 4 -di…
Genetic organization of the citCDEF locus and identification of mae and clyR genes from Leuconostoc mesenteroides.
1999
ABSTRACT In this paper, we describe two open reading frames coding for a NAD-dependent malic enzyme ( mae ) and a putative regulatory protein ( clyR ) found in the upstream region of citCDEFG of Leuconostoc mesenteroides subsp. cremoris 195. The transcriptional analysis of the citrate lyase locus revealed one polycistronic mRNA covering the mae and citCDEF genes. This transcript was detected only on RNA prepared from cells grown in the presence of citrate. Primer extension experiments suggest that clyR and the citrate lyase operon are expressed from a bidirectional A-T-rich promoter region located between mae and clyR.
The inefficient aerobic energetics ofZymomonas mobilis: Identifying the bottleneck
2014
To investigate the mechanisms of Zymomonas mobilis uncoupled aerobic metabolism, growth properties of the wild-type strain Zm6 were compared to those of its respiratory mutants cytB and cydB, and the effects of the ATPase inhibitor DCCD on growth and intracellular ATP concentration were studied. The effects of the ATPase inhibitor DCCD on growth and intracellular ATP concentration strongly indicated that the apparent lack of oxidative phosphorylation in aerobically growing Z. mobilis culture might be caused by the ATP hydrolyzing activity of the H(+) -dependent ATPase in all analyzed strains. Aerobic growth yields of the mutants, and their capacity of oxidative ATP synthesis with ethanol we…