6 research outputs found
Processus relationnels structurant la relation thérapeutique médecin-malade en médecine générale
MONTPELLIER-BU MĂ©decine UPM (341722108) / SudocPARIS-BIUM (751062103) / SudocMONTPELLIER-BU MĂ©decine (341722104) / SudocSudocFranceF
Efficient Inhibition of Telomerase by Nickel-Salophen Complexes
International audienc
Interaction of Polycationic Ni(II)-Salophen Complexes with G-Quadruplex DNA
International audienc
Interaction of Polycationic Ni(II)-Salophen Complexes with GâQuadruplex DNA
A series
of nine NiÂ(II) salophen complexes involving one, two,
or three alkyl-imidazolium side-chains was prepared. The lengths of
the side-chains were varied from one to three carbons. The crystal
structure of one complex revealed a square planar geometry of the
nickel ion. Fluorescence resonance energy transfer melting of G-quadruplex
structures in the presence of salophen complex were performed. The
G-quadruplex DNA structures were stabilized in the presence of the
complexes, but a duplex DNA was not. The binding constants of the
complexes for parallel and antiparallel G-quadruplex DNA, as well
as hairpin DNA, were measured by surface plasmon resonance. The compounds
were selective for G-quadruplex DNA, as reflected by equilibrium dissociation
constant <i>K</i><sub>D</sub> values in the region 0.1â1
ÎŒM for G-quadruplexes and greater than 2 ÎŒM for duplex
DNA. Complexes with more and shorter side-chains had the highest binding
constants. The structural basis for the interaction of the complexes
with the human telomeric G-quadruplex DNA was investigated by computational
studies: the aromatic core of the complex stacked over the last tetrad
of the G-quadruplex with peripherical cationic side chains inserted
into opposite grooves. Biochemical studies (telomeric repeat amplification
protocol assays) indicated that the complexes significantly inhibited
telomerase activity with IC<sub>50</sub> values as low as 700 nM;
the complexes did not significantly inhibit polymerase activity
Interaction of Polycationic Ni(II)-Salophen Complexes with GâQuadruplex DNA
A series
of nine NiÂ(II) salophen complexes involving one, two,
or three alkyl-imidazolium side-chains was prepared. The lengths of
the side-chains were varied from one to three carbons. The crystal
structure of one complex revealed a square planar geometry of the
nickel ion. Fluorescence resonance energy transfer melting of G-quadruplex
structures in the presence of salophen complex were performed. The
G-quadruplex DNA structures were stabilized in the presence of the
complexes, but a duplex DNA was not. The binding constants of the
complexes for parallel and antiparallel G-quadruplex DNA, as well
as hairpin DNA, were measured by surface plasmon resonance. The compounds
were selective for G-quadruplex DNA, as reflected by equilibrium dissociation
constant <i>K</i><sub>D</sub> values in the region 0.1â1
ÎŒM for G-quadruplexes and greater than 2 ÎŒM for duplex
DNA. Complexes with more and shorter side-chains had the highest binding
constants. The structural basis for the interaction of the complexes
with the human telomeric G-quadruplex DNA was investigated by computational
studies: the aromatic core of the complex stacked over the last tetrad
of the G-quadruplex with peripherical cationic side chains inserted
into opposite grooves. Biochemical studies (telomeric repeat amplification
protocol assays) indicated that the complexes significantly inhibited
telomerase activity with IC<sub>50</sub> values as low as 700 nM;
the complexes did not significantly inhibit polymerase activity
Pru p 7 sensitization is a predominant cause of severe, cypress pollenâassociated peach allergy
International audienceBACKGROUND:Peach is a common elicitor of food allergic reactions. Peach-induced immediate reactions may occur as benign pollen-food syndromes, usually due to birch pollen-related PR-10 cross-reactivity in temperate climates, and as potentially severe primary food allergies, predominantly related to nsLTP Pru p 3 in Mediterranean regions. The newly described peach allergen Pru p 7 has gained recent attention as a potential peach allergy severity marker. Sensitization to Pru p 7 and its allergenic homologues of the gibberellin-regulated protein family occurs in areas with high Cupressaceae tree pollen exposure.OBJECTIVE:We sought to investigate the distribution, clinical characteristics and molecular associations of Pru p 7 sensitization among subjects with suspected peach allergy in different regions of France.METHODS:Subjects with suspected peach allergy (n = 316) were included. Diagnostic work-up was performed according to current guidelines, including open food challenge when required. IgE antibody measurements and competition experiments were performed using the ImmunoCAP assay platform.RESULTS:Sensitization to Pru p 7 was present in 171 (54%) of all subjects in the study and in 123 of 198 (62%) diagnosed as peach allergic, more than half of whom were sensitized to no other peach allergen. Frequency and magnitude of Pru p 7 sensitization were associated with the presence of peach allergy, the clinical severity of peach-induced allergic reactions and the level of cypress pollen exposure. Cypress pollen extract completely outcompeted IgE binding to Pru p 7. Pru p 7 was extremely potent in basophil activation tests.CONCLUSION AND CLINICAL RELEVANCE:A subtype of Cupressaceae pollinosis, characterized by Pru p 7 sensitization, can be an underlying cause of severe peach allergy