Search results for "TOXICITY"
showing 10 items of 2261 documents
THIOPYRANO[2,3-E]INDOL-2-ONES: ANGELICIN HETEROANALOGUES WITH POTENT PHOTOANTIPROLIFERATIVE ACTIVITY
2008
A new class of compounds, the thiopyrano[2,3-e]indol-2-ones, bioisosters of the angular furocoumarin angelicin, was synthesized with the aim of obtaining new photochemotherapeutic agents. In particular 7,8-dimethyl-thiopyranoindolone 6c s showed a remarkable phototoxicity and a great dose UVA dependence reaching IC(50) values at submicromolar level. This latter photoinduced a massive apoptosis and a remarkable photodamage to lipids and proteins. Although it did not intercalate DNA, it was able to cause photooxidation of DNA bases.
Role of neuroinflammation in ethanol neurotoxicity
2019
Abstract Alcohol is a neurotoxic compound whose abuse can cause alterations in brain structure and functions, although these effects are more dramatic while the brain develops. The molecular mechanisms of neurotoxic effects of alcohol are complex and remain largely unknown. Current evidence from human and animal studies supports the role of the neuroimmune system in many actions of ethanol on the central nervous system, including neurotoxicity. Different studies have shown that, by activating innate immune receptors TLRs (Toll-like receptors) and (NOD)-like receptors (inflammasome NLRs) in glial cells, alcohol triggers signaling pathways which culminate in the production of pro-inflammatory…
A New 1D Ni (II) Coordination Polymer of s-Triazine Type Ligand and Thiocyanate as Linker via Unexpected Hydrolysis of 2,4-Bis(3,5-dimethyl-1H-pyrazo…
2023
A new 1D Ni(II) coordination polymer was synthesized by the reaction of NiSO4·6H2O with 2,4-bis(3,5-dimethyl-1H-pyrazol-1-yl)-6-methoxy-1,3,5-triazine (BPT) and SCN− as a linker in an acidic medium by heating under reflux conditions. Unusually, the BPT ligand underwent acid-mediated hydrolysis by losing one of the pyrazolyl arms afforded the polymeric [Ni(MPT)(H2O)(SCN)2]n complex (MPT: 4-(3,5-dimethyl-1H-pyrazol-1-yl)-6-methoxy-1,3,5-triazin-2-ol. The Ni(II) center is coordinated with one MPT as a bidentate NN-chelate, one water molecule, and two thiocyanate groups in cis positions to one another. One of the thiocyanate groups acts as a bridging ligand between metal centers, l…
Lack of Detrimental Effects of Bacillus thuringiensis Cry Toxins on the Insect Predator Chrysoperla carnea : a Toxicological, Histopathological, and …
2006
ABSTRACT The effect of Cry proteins of Bacillus thuringiensis on the green lacewing ( Chrysoperla carnea ) was studied by using a holistic approach which consisted of independent, complementary experimental strategies. Tritrophic experiments were performed, in which lacewing larvae were fed Helicoverpa armigera larvae reared on Cry1Ac, Cry1Ab, or Cry2Ab toxins. In complementary experiments, a predetermined amount of purified Cry1Ac was directly fed to lacewing larvae. In both experiments no effects on prey utilization or fitness parameters were found. Since binding to the midgut is an indispensable step for toxicity of Cry proteins to known target insects, we hypothesized that specific bind…
Fish tolerance to organophosphate-induced oxidative stress is dependent on the glutathione metabolism and enhanced by N-acetylcysteine
2003
Abstract Dichlorvos (2,2-dichlorovinyl dimethyl phosphate, DDVP) is an organophosphorus (OP) insecticide and acaricide extensively used to treat external parasitic infections of farmed fish. In previous studies we have demonstrated the importance of the glutathione (GSH) metabolism in the resistance of the European eel ( Anguilla anguilla L.) to thiocarbamate herbicides. The present work studied the effects of the antioxidant and glutathione pro-drug N -acetyl- l -cysteine (NAC) on the survival of a natural population of A. anguilla exposed to a lethal concentration of dichlorvos, focusing on the glutathione metabolism and the enzyme activities of acetylcholinesterase (AChE) and caspase-3 a…
Increased recovery of brain acetylcholinesterase activity in dichlorvos-intoxicated European eels Anguilla anguilla by bath treatment with N-acetylcy…
2003
Organophosphate (OP) pesticides are widely used as antiparasitic chemicals in finfish aquaculture. However, current antidotes cannot be applied to treat intoxicated fish. We showed in previous studies the importance of glutathione (GSH) metabolism in pesticide resistance of the European eel Anguilla anguilla L. The present work studied the effects of the antioxidant and glutathione pro-drug N-acetyl-l-cysteine (NAC) on the recovery of European eels exposed for 96 h to a sublethal concentration (0.17 mg l^-1; 20% of its 96 h LC50) of the OP pesticide dichlorvos (2,2-dichlorovinyl dimethyl phosphate; DDVP). This insecticide and acaricide decreased muscular GSH content and increased oxidised g…
Screening for Bacillus thuringiensis Crystal Proteins Active against the Cabbage Looper, Trichoplusia ni
2000
Abstract Toxicity tests were performed to find among Cry1 and Cry2 Bacillus thuringiensis crystal proteins those with high activity against the cabbage looper. Tests were performed with neonate larvae on surface-contaminated artificial diet. The crystal proteins found to be toxic were, from higher to lower toxicity: Cry1Ac, Cry1Ab, Cry1C, Cry2Aa, Cry1J, and Cry1F (LC50 of 1.1–4.1, 3.4–4.4, 12, 34, 87, and 250 ng/cm2, respectively). Cry1B, Cry1D, and Cry1E can be considered nontoxic (LC50 higher than 2500 ng/cm2). Cry1Aa was moderately toxic to nontoxic, depending on the source (LC50 of 420 ng/cm2 from PGS and 8100 ng/cm2 from Ecogen). In vitro binding assays with trypsin-activated 125I-labe…
Assessment of the toxicity of a pesticide with a two-generation reproduction test using Daphnia magna.
2000
Abstract Daphnia magna (F 0 generation) were exposed during 21 days to different diazinon concentrations. Offspring (animals from the first and third brood: F 1 (1st) and F 1 (3rd), respectively) were transferred to a free pesticide medium during a 21-day recovery period. The algae Nannochloris oculata (5×10 5 cells/ml) were used as food. In this recovery study, survival, growth and reproduction (mean total young per female, mean brood size, onset of reproduction and mean number broods per female) were assessed as individual parameters, and the intrinsic rate of natural increase ( r ) as population parameter for F 1 (1st and 3rd broods) daphnids. Reproduction as well as survival was still r…
Physiological Perturbations in Several Generations of Daphnia magna Straus Exposed to Diazinon
2000
Abstract Daphnia magna was exposed to sublethal diazinon concentrations (0.05, 0.1, 0.5, 0.75, and 1.0 ng/L) for 21 days. The algae Nannochloris oculata (5×10 5 cells/mL) was used to feed the daphnids. Chronic toxicity tests were carried out using neonates of F 1 (first brood) and F 1 (third brood) offspring generations from parentals (F 0 ) preexposed to the organophosphate. The effect of diazinon on survival, reproduction, and growth was monitored for the selected daphnid generations. The parameters used to evaluate pesticide effect on reproduction were mean total young per female, mean brood size, time to first reproduction, mean number broods per female, and intrinsic rate of natural in…
Toxicity of lindane, atrazine, and deltamethrin to early life stages of zebrafish (Brachydanio rerio).
1990
Fertilized eggs of zebrafish were exposed under flow-through conditions to several concentrations of the following pesticides: lindane 40, 80, 110, 130, and 150 micrograms/liter; atrazine 300, 1300, and 9100 micrograms/liter; deltamethrin 0.5, 0.8, and 1.2 micrograms/liter. Hatching, abnormalities in development (external deformations, edema, etc.), and mortality were recorded over a period of 35 days. At the end of the experiment, the body lengths of the fish were measured. Survival of juvenile fish after 35 days was reduced by increasing concentrations of all xenobiotics tested: lindane enhanced the mortality from 110 micrograms/liter and atrazine from 1300 micrograms/liter, and deltameth…