Search results for "Thiazines"
showing 10 items of 20 documents
Increased survival of honeybees in the laboratory after simultaneous exposure to low doses of pesticides and bacteria
2018
Recent studies of honeybees and bumblebees have examined combinatory effects of different stressors, as insect pollinators are naturally exposed to multiple stressors. At the same time the potential influences of simultaneously occurring agricultural agents on insect pollinator health remain largely unknown. Due to different farming methods, and the drift of applied agents and manure, pollinators are most probably exposed to insecticides but also bacteria from organic fertilizers at the same time. We orally exposed honeybee workers to sub-lethal doses of the insecticide thiacloprid and two strains of the bacterium Enterococcus faecalis, which can occur in manure from farming animals. Our re…
ERa dimerization: a key factor for the weak estrogenic activity of an ERa modulator unable to compete with estradiol in binding assays
2016
PMID: 27400858; International audience; AbstractEstrothiazine (ESTZ) is a weak estrogen sharing structural similarities with coumestrol. ESTZ failed to compete with [3H]17β-estradiol ([3H]17β-E2) for binding to the estrogen receptor α (ERα), questioning its ability to interact with the receptor. However, detection by atomic force spectroscopy (AFS) of an ESTZ-induced ERα dimerization has eliminated any remaining doubts. The effect of the compound on the proliferation of ERα-positive and negative breast cancer cells confirmed the requirement of the receptor. The efficiency of ESTZ in MCF-7 cells was weak without any potency to modify the proliferation profile of estradiol and coumestrol. Gro…
Binding of several phenothiazine neuroleptics to a common binding site of alpha 1-acid glycoprotein, orosomucoid.
1983
The interaction of several phenothiazine neuroleptics with alpha 1-acid glycoprotein was investigated using circular dichroism and equilibrium dialysis techniques. For chlorpromazine only, one high-affinity binding site of the protein was found. The binding of the drug to this single site generated typical polyphasic extrinsic Cotton effects. Since several other phenothiazine neuroleptics gave qualitatively comparable extrinsic Cotton effects in the presence of alpha 1-acid glycoprotein and potently inhibited the binding of chlorpromazine to the single site, it was concluded that all phenothiazine derivatives investigated bound preferentially to only one common binding site of the alpha 1-a…
FTIR determination of Aspartame and Acesulfame-K in tabletop sweeteners.
2004
Two different strategies for sweeteners determination in tabletop samples by Fourier transform middle-infrared (FTIR) spectrometry, an off-line and a fully mechanized extraction of Aspartame and Acesulfame-K with different mixtures of chloroform and methanol, have been developed. The off-line method involves the extraction of both active principles by sonication of samples with 25:75 v/v CHCl3/CH3OH and direct measurement of the peak height values at 1751 cm(-1), corrected using a baseline defined at 1850 cm(-1) for Aspartame, and measurement of the peak height at 1170 cm(-1) in the first-order derivative spectra, corrected by using a horizontal baseline established at 1850 cm(-1), for Aces…
Characterization of basic drug–human serum protein interactions by capillary electrophoresis
2006
Drug-protein interactions are determining factors in the therapeutic, pharmacodynamic and toxicological drug properties. The affinity of drugs towards plasmatic proteins is apparently well established in bibliography. Albumin (HSA) especially binds neutral and negatively charged compounds; alpha(1)-acid glycoprotein (AGP) binds many cationic drugs, lipoproteins bind to nonionic and lipophilic drugs and some anionic drugs while globulins interact inappreciably with the majority of drugs. In this paper, the characterization of the interaction between cationic drugs, beta-blockers and phenotiazines towards HSA, AGP, and both HSA + AGP mixtures of proteins under physiological conditions by CE-f…
Ovicide-induced serosa degeneration and its impact on embryonic development in Manduca sexta (Insecta: Lepidoptera)
2003
Abstract Eggs of Manduca sexta treated with the ovicide Ov. 165049 turn orange, and the embryos later die. The orange pigmentation is at first confined to the serosa, and is accompanied by pathological changes of serosal cells. Lipid vesicles aggregate and spindle-shaped electron-lucent vesicles—normally forming a single layer below the apical cell surface—greatly accumulate. The mitochondria swell considerably, and their matrices become electron-lucent. Subsequently, the serosal cells develop additional features of necrosis. They form many autophagic vacuoles which contain mostly degradating mitochondria, but also segregated rough endoplasmic reticulum (rER) and glycogen granules. The whol…
Phenothiazines interfere with dopaminergic neurodegeneration in Caenorhabditis elegans models of Parkinson's disease
2010
Oxidative stress is involved in the pathogenesis of various neurodegenerative disorders, conventional antioxidant strategies have yet been of limited success. We have employed transgenic Caenorhabditis elegans expressing DsRed2 in dopaminergic neurons and CFP pan-neuronally, to characterize in larval and adult animals the effects of rotenone and 1-methyl-4-phenyl-pyridinium (MPP(+)) on the dopaminergic system. Investigating the antioxidant phenothiazine and different derived antipsychotic drugs, it was found that free phenothiazine exerted strong neuroprotection at the cellular level and resulted in a better performance in behavioral assays, whereas apomorphine and other dopamine agonists o…
Update on topical carbonic anhydrase inhibitors
2001
Topical carbonic anhydrase inhibitors are a novel addition to the armamentarium of medical glaucoma treatment; dorzolamide has been available since 1995 and brinzolamide since 1998. They lower intraocular pressure by inhibiting carbonic anhydrase, a key enzyme for aqueous humor formation. Intraocular pressure-lowering activity of the substances appears to be the same and is similar to that of most other agents, but it does not reach the activity of the unselective beta-blocker timolol or the prostaglandin latanoprost. On concomitant treatment, additivity is reached with all other topical agents. A possible improvement of blood flow may offer an additional benefit, but its significance for t…
Photoinduced chemiluminescence of pharmaceuticals
2005
Abstract A screening test for the forward development of chemiluminescence systems able to determine pharmaceutical compounds is reported. The test is based on the on-line photodegradation of the drugs by using a photoreactor consisting of 697 cm × 0.5 mm PTFE tubing helically coiled around an 8 W low-pressure mercury lamp. Photodegraded pharmaceuticals are detected by direct chemiluminescence of the resulting photofragments and their subsequent reaction with potassium permanganate in sulphuric acid medium as oxidant. The screening comprised 97 compounds with different molecular structures and relevant members of the most important families of pharmaceuticals are tested (amino acids, carbox…
Randomized Trial of Brinzolamide/Brimonidine Versus Brinzolamide Plus Brimonidine for Open-Angle Glaucoma or Ocular Hypertension
2014
Introduction Fixed-combination intraocular pressure (IOP)—lowering medications simplify treatment regimens for patients requiring 2 ocular hypotensive agents to maintain sufficiently low IOP. The aim of this study was to evaluate the safety and efficacy of fixed-combination brinzolamide 1%/brimonidine 0.2% (BBFC) versus concomitant administration of brinzolamide 1% plus brimonidine 0.2% (BRINZ + BRIM) in patients with open-angle glaucoma or ocular hypertension. Methods This was a prospective, phase 3, multicenter, double-masked, 6-month trial. Patients who had insufficient IOP control with monotherapy or who were receiving 2 IOP-lowering medications were randomized 1:1 to receive twice-dail…