Search results for "interactions."
showing 10 items of 1865 documents
Metformin influences drug sensitivity in pancreatic cancer cells
2018
Abstract Pancreatic ductal adenocarcinoma (PDAC) is an aggressive, highly metastatic malignancy and accounts for 85% of pancreatic cancers. PDAC patients have poor prognosis with a five-year survival of only 5–10% after diagnosis and treatment. Pancreatic cancer has been associated with type II diabetes as the frequency of recently diagnosed diabetics that develop pancreatic cancer within a 10-year period of initial diagnosis of diabetes in increased in comparison to non-diabetic patients. Metformin is a very frequently prescribed drug used to treat type II diabetes. Metformin acts in part by stimulating AMP-kinase (AMPK) and results in the suppression of mTORC1 activity and the induction o…
Nuclear anapole moment interaction in BaF from relativistic coupled-cluster theory
2018
We present high accuracy relativistic coupled cluster calculations of the P-odd interaction coefficient $W_A$ describing the nuclear anapole moment effect on the molecular electronic structure. The molecule under study, BaF, is considered a promising candidate for the measurement of the nuclear anapole moment, and the preparation for the experiment is now underway [Altunas et al., Phys. Rev. Lett. 120, 142501 (2018)]. Influence of various computational parameters (size of the basis set, treatment of relativistic effects, and treatment of electron correlation) on the calculated $W_A$ coefficient is investigated and a recommended value of 147.7 Hz with an estimated uncertainty of 1.5% is prop…
Viscosity-mediated negative food effect on oral absorption of poorly-permeable drugs with an absorption window in the proximal intestine: In vitro ex…
2014
Concomitant food intake can diminish oral absorption of drugs with limited permeability and an absorption window in the proximal intestine, due to viscosity-mediated decrease in dosage form disintegration time and drug dissolution rate. Three poorly-permeable drugs (atenolol, metformin hydrochloride, and furosemide) exhibiting negative food effect, and one highly-soluble and highly-permeable (metoprolol tartrate), serving as a negative control, were selected for the study. In vitro and in silico tools were used to evaluate the influence of media viscosity on drug bioperformance under fasted and fed conditions. The obtained results demonstrated that increased medium viscosity in the presence…
Partially competitive inhibition of intestinal baclofen absorption by beta-alanine, a nonessential dietary aminoacid.
1991
In situ intestinal absorption of baclofen in the rat in the presence of beta-alanine has been investigated. Through the perfusion of 0.50 mM baclofen solutions containing variable concentrations of the aminoacid (from 5 to 100 mM), a partially competitive inhibition of baclofen absorption was characterized: absorption rate pseudoconstants of the spasmolytic drug decrease as beta-alanine concentration increases, until a limiting value is obtained (36.8 per cent of that found for baclofen alone). A computer method was developed in order to calculate parameters governing baclofen absorption in the presence of beta-aminoacid, with the following results: Vm = 11.22 mM h-1; Km = 7.42 mM; Ki = 2.4…
Investigation of molecular dimers by ensemble and single molecule spectroscopy
2002
International audience; We have investigated molecular dimers with different electronic coupling strengths by bulk and single molecule spectroscopy. In one of the dimers the two monomers (perylene-monoimide) are directly connected via a single bond while in the other one they are separated by the benzil motif. The close proximity of the monomers in the first case gives rise to excitonic band splitting which is clearly observable in the bulk absorption spectra. For the benzil structure the electronic interactions are governed by Förster-type energy hopping between the monomers. Fluorescence intensity trajectories at the single molecule level show one-step and two-step bleaching behaviour whi…
Crystallographic and (spectro)electrochemical characterizations of cobalt(II) 10-phenyl-5,15-di-p-tolylporphyrin
2021
International audience; The synthesis, cyclic and rotating disk electrode voltammograms, UV-visible absorption and Xray diffraction analyses of cobalt(II) 10-phenyl-5,15-dip -tolylporphyrin (1-Co) are described. 1-Co was crystallized by slow diffusion of n-hexane into a concentrated CH2Cl2 solution. X-ray diffraction analyses reveals porphyrin aromatic cycle stacking in the crystal, C-H•••π interactions of the CH2Cl2 solvent with the π-system of one tolyl group and Co(II)•••π (porphyrin ring) interactions. The abstraction of 1.0 F/mol during the electrolysis at the first oxidation potential was followed by spectroelectrochemistry. It leads to the Co(II) → Co(III) transformation rather than …
Maternal transfer of antibodies: raising immuno-ecology issues.
2007
The transfer of antibodies from mother to offspring has broad potential implications in evolutionary ecology, from the adaptive value of maternal effects to the role of transgenerational plasticity in host-parasite interactions. Recent contributions have addressed key issues such as environmental and genetic factors affecting the amount of antibodies transferred and whether maternal antibodies affect offspring immunity, but little is still known about the implications of the maternal transfer of antibodies in natural populations. By its position at the crossroads between population ecology, animal science, medicine and epidemiology, current studies of the role of the maternal transfer of an…
The influence of food competition and host specificity on the transmission of Triaenophorus crassus (Cestoda) and Cystidicola farionis (Nematoda) to …
2000
Abstract As a superior competitor for planktonic food, vendace ( Coregonus albula ), when abundant, is expected to displace whitefish ( Coregonus lavaretus ) from feeding on plankton and to force it to rely more on benthic food. The predicted result would be a reduced abundance of the copepod-transmitted cestode Triaenophorus crassus in whitefish, but an increase in the abundance of the nematode Cystidicola farionis transmitted via benthic amphipods. We studied the occurrence of both parasites in whitefish during 1991–1996 in three interconnected areas at Lake Saimaa, Finland, where the densities of the vendace stocks varied due to natural fluctuation in year-class strengths. In accordance …
Therapeutic Vaccination of Hematopoietic Cell Transplantation Recipients Improves Protective CD8 T-Cell Immunotherapy of Cytomegalovirus Infection
2021
Reactivation of latent cytomegalovirus (CMV) endangers the therapeutic success of hematopoietic cell transplantation (HCT) in tumor patients due to cytopathogenic virus spread that leads to organ manifestations of CMV disease, to interstitial pneumonia in particular. In cases of virus variants that are refractory to standard antiviral pharmacotherapy, immunotherapy by adoptive cell transfer (ACT) of virus-specific CD8+ T cells is the last resort to bridge the “protection gap” between hematoablative conditioning for HCT and endogenous reconstitution of antiviral immunity. We have used the well-established mouse model of CD8+ T-cell immunotherapy by ACT in a setting of experimental HCT and mu…
Synthetic antioxidants: biochemical actions and interference with radiation, toxic compounds, chemical mutagens and chemical carcinogens.
1984
Abstract Biological actions of 4 commonly used synthetic antioxidants — butylated hydroxyanisole, butylated hydroxytoluene, ethoxquin and propul gallate — on the molecular, cellular and organ level are compiled. Such actions may be divided into modulation of growth, macromolecule synthesis and differentiation, modulation of immune response, interference with oxygen activation and miscellaneous. Moreover, an overview of beneficial and adverse interactions of these antioxidants with exogenous noxae is given. Beneficial interactions include radioprotection, protection against acute toxicity of chemicals, antimutagenic activity and antitumorigenic action. Possible mechanisms of the antitumorige…