Search results for "Penicillin"
showing 10 items of 50 documents
Benzodiazepine receptor interactions may be involved in the neurotoxicity of various penicillin derivatives
1980
The interaction of seven penicillin derivatives with specific [3H]flunitrazepam binding to benzodiazepine receptors was investigated. The affinities of the penicillins for benzodiazepine receptor seemed to depend on the lipophilia of the derivatives. The concentrations of the penicillins which inhibit specific [3H]flunitrazepam binding are consistent with penicillin levels found in the central nervous system of patients developing penicillin induced convulsions. The results suggest that penicillins inhibit GABAergic transmission not only at the GABA receptor, but also at the benzodiazepine receptor, which is thought to be part of a neuronal system facilitating GABAergic transmission. Both m…
In situ formation of pyronin dyes for fluorescence protease sensing
2017
International audience; We report a reaction-based strategy for the fluorogenic detection of protease activity. Based on the "covalent-assembly" probe design principle recently put forward by the Yang group for detection of Sarin related threats (J. Am. Chem. Soc., 2014, 136, 6594-6597), we have designed two unusual nonfluorescent caged precursors (mixed bis-aryl ethers) which are readily converted into a fluorescent unsymmetrical pyronin dye through a domino cyclisation-aromatisation reaction triggered by penicillin G acylase (PGA) or leucine aminopeptidase (LAP). Fluorescence-based in vitro assays and HPLCfluorescence/- MS analyses support the claimed activation mechanism whose the furthe…
Bacterial sensors based on biosilica immobilization for label-free OWLS detection
2013
In the last years, a new group of enzymes, the so-called silicateins, have been identified and characterized, which form the axial filaments of the spicules of the siliceous sponges, consisting of not only amorphous silica among others. These enzymes are able to catalyze the polycondensation and deposition of silica at mild conditions. Silicateins can be expressed in Escherichia coli. The recombinant proteins are expressed on the surface of the cell wall and are able to catalyze the formation of a polysilicate net around the bacterial cells providing the possibility for further attachment to the surface of SiO2 containing sensor chips. With this mild immobilization process it is now possibl…
Synergistic effect between amoxicillin and TLR ligands on dendritic cells from amoxicillin-delayed allergic patients.
2013
Journal Article; Amoxicillin, a low-molecular-weight compound, is able to interact with dendritic cells inducing semi-maturation in vitro. Specific antigens and TLR ligands can synergistically interact with dendritic cells (DC), leading to complete maturation and more efficient T-cell stimulation. The aim of the study was to evaluate the synergistic effect of amoxicillin and the TLR2, 4 and 7/8 agonists (PAM, LPS and R848, respectively) in TLR expression, DC maturation and specific T-cell response in patients with delayed-type hypersensitivity (DTH) reactions to amoxicillin. Monocyte-derived DC from 15 patients with DTH to amoxicillin and 15 controls were cultured with amoxicillin in the pr…
Organometallic complexes with biological molecules. XVII. Triorganotin(IV) complexes with amoxicillin and ampicillin.
2002
Novel triorganotin(IV) complexes of two β-lactamic antibiotics, 6-[D-(-)-β-amino-p-hydroxyphenyl-acetamido]penicillin (=amoxicillin) and 6-[D-(-)-α-aminobenzyl]penicillin (=ampicillin), have been synthesized and investigated both in solid and solution states. The complexes corresponded to the general formula R3Sn(IV)antib·H2O (R=Me, n-Bu, Ph; antib=amox=amoxicillinate or amp=ampicillinate). Structural investigations about configuration in the solid state have been carried out by interpreting experimental IR and 119Sn Mössbauer data. In particular, IR results suggested polymeric structures both for R3Sn(IV)amox·H2O and R3Sn(IV)amp·H2O. Moreover, both antibiotics appear to behave as monoanion…
Staphylococcus saprophyticus as an Unusual Agent of Nosocomial Pneumonia
1999
Study of spindle-spike interactions: Features of basal ganglia control
1987
Summary Changes in cortical spindle distribution following penicillin (PCN) injections were studied in feline generalized PCN epilepsy. PCN activation caused no substantial changes in spindle duration, frequency and intraburst frequency, while significant reductions in the amplitude of the negative waves were noted. At the same time combinations of spindle waves and epileptic complexes were recorded with one or more spikes randomly occurring at the beginning, in the middle, or at the end of a spindle envelope. Low frequency stimulation of the caudate nucleus induced a certain degree of enhancement in cortical precruciate spike frequency while high frequency activation of the entopeduncular …
Chancre of the eyelid as manifestation of primary syphilis, and precocious chorioretinitis and uveitis in an HIV-infected patient: a case report
2012
Abstract Background Ocular syphilis is often difficult to diagnose because of the wide variation in clinical features. HIV co-infection may further complicate the picture. Case presentation Herein the authors report an unusual primary syphilitic ocular lesion in a 45-year-old Italian HIV-infected bisexual man who presented with a unilateral eyelid lesion. Associated precocious signs and symptoms in the posterior segment of both eyes, bilateral chorioretinitis and uveitis, are described. Intravenous penicillin and steroid treatment produced a rapid improvement in clinical status and complete resolution. Conclusions Careful questioning about sexual behavior is crucial for unmasking unusual fe…
Preparation, characterization and in vitro antimicrobial activity of ampicillin-loaded polyethylcyanoacrylate nanoparticles.
1998
In this paper, the experimental conditions for preparing ampicillin-loaded polyethylcyanoacrylate (PECA) nanoparticles are described. The effects of drug concentration and surfactant type in the polymerization medium on the particle size distribution and loading capacity were studied. The results of these studies show that only the type of surfactant has an impact on the nanoparticle dimensions. The release rate of ampicillin from PECA nanoparticles at pH 7.4 (extracellular value pH) performed either with and without esterases, show that the drug release is considerably increased in the presence of these exzymes. The results of drug release study at pH 1.1 (simulated gastric juice) are very…