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1.
Food Chem Toxicol ; 155: 112357, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34217737

RESUMO

In 2015, the Expert Panel of the Flavor and Extract Manufacturers Association (FEMA) initiated a program for the re-evaluation of the safety of over 250 natural flavor complexes (NFCs) used as flavor ingredients. This publication, the sixth in the series, will summarize the re-evaluation of eight NFCs whose constituent profiles are characterized by significant amounts of eucalyptol and/or other cyclic ethers. This re-evaluation was based on a procedure first published in 2005 and subsequently updated in 2018 that evaluates the safety of naturally occurring mixtures for their intended use as flavoring ingredients. The procedure relies on a complete chemical characterization of the NFC intended for commerce and the organization of its chemical constituents into well-defined congeneric groups. The safety of the NFC is evaluated using the well-established and conservative threshold of toxicological concern (TTC) concept in addition to data on absorption, metabolism and toxicology of the constituents of the congeneric groups and the NFC under evaluation. Eight NFCs derived from the Eucalyptus, Melaleuca, Origanum, Laurus, Rosmarinus and Salvia genera were affirmed as generally recognized as safe (GRAS) under their conditions of intended use as flavor ingredients based on an evaluation of each NFC and the constituents and congeneric groups therein.


Assuntos
Éteres Cíclicos/toxicidade , Aromatizantes/toxicidade , Óleos de Plantas/toxicidade , Animais , Células CHO , Linhagem Celular Tumoral , Qualidade de Produtos para o Consumidor , Cricetulus , Éteres Cíclicos/química , Eucaliptol/toxicidade , Feminino , Aromatizantes/química , Humanos , Masculino , Camundongos , Testes de Mutagenicidade , Nível de Efeito Adverso não Observado , Óleos de Plantas/química , Plantas/química , Gravidez , Ratos Wistar , Medição de Risco , Salmonella typhimurium/efeitos dos fármacos
2.
Fitoterapia ; 142: 104520, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32088280

RESUMO

Chemical and biocatalytic synthesis of seven previously undescribed marchantin A ester derivatives has been presented. Chemical synthesis afforded three peresterified bisbibenzyl products (TE1-TE3), while enzymatic method, using lipase, produced regioselective monoester derivatives (ME1-ME4). The antiproliferative activities of all prepared derivatives of marchantin A were tested on MRC-5 healthy human lung fibroblast, A549 human lung cancer, and MDA-MB-231 human breast cancer cell lines. All tested esters were less cytotoxic in comparison to marchantin A, but they also exhibited lower cytotoxicity against healthy cells. Monoesters displayed higher cytotoxic activities than the corresponding peresterified products, presumably due to the presence of free catechol group. Monohexanoyl ester ME3 displayed the same IC50 like marchantin A against MDA-MB-231 cells, but the selectivity was higher. In this way, regioselective enzymatic monoesterification enhanced selectivity of marchantin A. ME3 was also the most active among all derivatives against lung cancer cells A549 with the slightly lower activity and selectivity in comparison to marchantin A.


Assuntos
Antineoplásicos Fitogênicos/química , Bibenzilas/química , Éteres Cíclicos/química , Células A549 , Antineoplásicos Fitogênicos/toxicidade , Bibenzilas/toxicidade , Ensaios de Seleção de Medicamentos Antitumorais , Esterificação , Éteres Cíclicos/toxicidade , Humanos
3.
Food Chem Toxicol ; 97S: S192-S200, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27697541

RESUMO

: The use of this material under current conditions is supported by existing information. This material was evaluated for genotoxicity, repeated dose toxicity, developmental and reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, as well as environmental safety. Data show that this material is not genotoxic nor does it have skin sensitization potential. The local respiratory toxicity endpoint was completed using the TTC (Threshold of Toxicological Concern) for a Cramer Class I material (1.4 mg/day). The repeated dose toxicity endpoint was completed using ethylene dodecanedioate (CAS # 54982-83-1) as a suitable read across analog, which provided a MOE > 100. The developmental and reproductive toxicity endpoint was completed using oxacyclohexadec-12-en-2-one, (12E)- (CAS # 111879-80-2) as a suitable read across analog, which provided a MOE > 100. The phototoxicity/photoallergenicity endpoint was completed based on suitable UV spectra along with data on the target material. The environmental endpoint was completed as described in the RIFM Framework along with data on the suitable read across analog oxacyclohexadec-12-en-2-one, (12E)- (CAS # 111879-80-2).


Assuntos
Éteres Cíclicos/toxicidade , Perfumes/toxicidade , Testes de Toxicidade/métodos , Animais , Qualidade de Produtos para o Consumidor , Dano ao DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Determinação de Ponto Final , Éteres Cíclicos/química , Nível de Efeito Adverso não Observado , Perfumes/química , Ratos , Medição de Risco
4.
Eksp Klin Farmakol ; 56(5): 18-21, 1993.
Artigo em Russo | MEDLINE | ID: mdl-8312801

RESUMO

Experiments on open-chest anaesthetized cats were made to test derivatives of crown ethers, such as benzylase-15-crown-5 and dibenzylase-15-crown-5 for their effects on myocardial ischemia and the functional status of a myocardial ischemic focus in temporary coronary occlusion during coronary spasm induced by dihydroergotamine and during coronary microthrombosis caused by ADP. When intravenously administered in doses of 0.5-15 mg/kg, the tested agents were found to enhance myocardial tolerance to ischemia, depressed ST segment in ischemia induced by coronary occlusion and administration of ATP, and prevented ST-segment depression during coronary spasm.


Assuntos
Éteres de Coroa , Éteres Cíclicos/uso terapêutico , Isquemia Miocárdica/tratamento farmacológico , Animais , Gatos , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Tolerância a Medicamentos , Eletrocardiografia/efeitos dos fármacos , Éteres Cíclicos/toxicidade , Feminino , Dose Letal Mediana , Masculino , Camundongos , Isquemia Miocárdica/fisiopatologia
6.
Toxicol Appl Pharmacol ; 93(1): 127-36, 1988 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-3353998

RESUMO

Methyl palmoxirate, an inhibitor of long-chain fatty acid oxidation, was administered by gavage (0, 1, 5, or 20 mg/kg/day) to female rats over the last third of gestation and throughout lactation. Weight gain (mid- and high-dosage group) and survivability (high-dosage group) were significantly (p less than or equal to 0.05) reduced in offspring of methyl palmoxirate-treated dams as compared to control offspring. Mid- and high-dosage male offspring found dead after Day 4 of lactation exhibited grossly distended bladders and renal pelves. A dosage-related increased incidence of dilated renal pelves was observed in both sexes at necropsy of 21-day-old mid- and high-dosage group pups. Microscopic examination of the urinary tracts of a number of affected pups revealed renal parenchymal atrophy and urethral obstruction. Drug disposition studies indicated lactating pups were exposed to significant amounts of methyl palmoxirate via mammary secretions. Cross-fostering experimentation suggested that some of the adverse effects observed in offspring were due to lactational, rather than in utero, exposure.


Assuntos
Compostos de Epóxi/toxicidade , Éteres Cíclicos/toxicidade , Ácidos Graxos/metabolismo , Hidronefrose/induzido quimicamente , Propionatos/toxicidade , Animais , Nitrogênio da Ureia Sanguínea , Relação Dose-Resposta a Droga , Feminino , Rim/efeitos dos fármacos , Rim/patologia , Lactação , Leite/metabolismo , Oxirredução , Gravidez , Proteínas/metabolismo , Ratos , Ratos Endogâmicos , Uretra/efeitos dos fármacos
7.
Farmakol Toksikol ; 47(5): 29-32, 1984.
Artigo em Russo | MEDLINE | ID: mdl-6238839

RESUMO

The authors studied antiarrhythmic properties of macrocyclic polyesters. Some of the esters exhibited antiarrhythmic activity coupled with low toxicity. It was found that antiarrhythmic action of these substances is not mediated via acetylcholine and/or catecholamine system responsible for nervous regulation of the cardiac activity. The compounds under study were found to have marked antifibrillar properties. Experiments on an isolated rat heart demonstrated calcium specificity of the antifibrillar action of cyclolactones. It is assumed that macrocyclic polyesters represent a new class of antiarrhythmic agents having a direct cardiotropic action.


Assuntos
Antiarrítmicos/uso terapêutico , Éteres Cíclicos/uso terapêutico , Aconitina , Animais , Antiarrítmicos/toxicidade , Arritmias Cardíacas/induzido quimicamente , Arritmias Cardíacas/tratamento farmacológico , Cloreto de Cálcio , Avaliação Pré-Clínica de Medicamentos , Éteres Cíclicos/toxicidade , Camundongos , Ratos , Estrofantinas , Fibrilação Ventricular/induzido quimicamente , Fibrilação Ventricular/tratamento farmacológico
9.
Cancer Treat Rep ; 60(10): 1585-9, 1976 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-828520

RESUMO

Thirty dogs in four different treatment schedules and 14 monkeys in a single multiple-treatment schedule were used to evaluate the toxicity of dianhydrogalactitol. Highest nontoxic, low toxic, high toxic, and lethal doses were established in single injection doses and five daily injections in dogs, and in five daily injections in monkeys. Dose ranges of 20-320 mg/m2 (single injection) and 5-80 mg/m2 (five daily injections) in dogs, and 3-96 mg/m2 (five daily injections) in monkeys were established. The monkeys were more sensitive than dogs to the low toxic dose and more tolerant to the high toxic dose in the repeated daily injections. The dose-response curves for the dogs and monkeys had similar slopes and inflection points. Because of the steep slope between the lethal dose and the highest nontoxic dose in both species, caution should be used in the initial clinical trials.


Assuntos
Galactitol/toxicidade , Álcoois Açúcares/toxicidade , Animais , Cães , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Éteres Cíclicos/toxicidade , Feminino , Galactitol/análogos & derivados , Haplorrinos , Dose Letal Mediana , Macaca mulatta , Masculino
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