Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 122
Filtrar
1.
Food Chem Toxicol ; 149 Suppl 1: 111989, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33465460

RESUMO

The existing information supports the use of this material as described in this safety assessment. 3,7-Dimethyl-1,3,6-octatriene was evaluated for genotoxicity, repeated dose toxicity, developmental and reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data from 3,7-dimethyl-1,3,6-octatriene and read-across analog myrcene (ß-myrcene; CAS # 123-35-3) show that 3,7-dimethyl-1,3,6-octatriene is not expected to be genotoxic and provide a calculated margin of exposure (MOE) >100 for the repeated dose toxicity and developmental and reproductive toxicity endpoints. The skin sensitization endpoint was completed using the dermal sensitization threshold (DST) for non-reactive materials (900 µg/cm 2 ); exposure is below the DST. The phototoxicity/photoallergenicity endpoints were evaluated based on ultraviolet (UV) spectra; 3,7-dimethyl-1,3,6- octatriene is not expected to be phototoxic/photoallergenic. The local respiratory toxicity endpoint was evaluated using the threshold of toxicological concern (TTC) for a Cramer Class I material, and the exposure to 3,7-dimethyl-1,3,6-octatriene is below the TTC (1.4 mg/day). The environmental endpoints were evaluated; 3,7-dimethyl-1,3,6- octatriene was found not to be persistent, bioaccumulative, and toxic (PBT) as per the International Fragrance Association (IFRA) Environmental Standards, and its risk quotients, based on its current volume of use in Europe and North America (i.e., Predicted Environmental oncentration/Predicted No Effect Concentration [PEC/PNEC]), are <1.


Assuntos
Odorantes , Animais , Relação Dose-Resposta a Droga , Humanos , Relação Quantitativa Estrutura-Atividade , Reprodução/efeitos dos fármacos , Medição de Risco , Testes de Toxicidade
2.
Food Chem Toxicol ; 144 Suppl 1: 111697, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32853699

RESUMO

The existing information supports the use of this material as described in this safety assessment. 2-Phenylpropionaldehyde was evaluated for genotoxicity, repeated dose toxicity, developmental and reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data on read-across analogs 3-phenylbutanal (CAS # 16251-77-7) and isopropylphenylbutanal (CAS # 125109-85-5) show that this material is not expected to be genotoxic. Data from the target material provide a calculated margin of exposure (MOE) >100 for the repeated dose toxicity endpoint and a No Expected Sensitization Induction Level (NESIL) of 380 µg/cm2 for the skin sensitization endpoint. The developmental and reproductive toxicity and the local respiratory toxicity endpoints were completed using the threshold of toxicological concern (TTC) for a Cramer Class I material (0.03 mg/kg/day and 1.4 mg/day, respectively). The phototoxicity/photoallergenicity endpoints were evaluated based on ultraviolet (UV) spectra; 2-phenylpropionaldehyde is not expected to be phototoxic/photoallergenic. The environmental endpoints were evaluated; 2-phenylpropionaldehyde was found not to be persistent, bioaccumulative, and toxic (PBT) as per the International Fragrance Association (IFRA) Environmental Standards, and its risk quotients, based on its current volume of use in Europe and North America (i.e., Predicted Environmental Concentration/Predicted No Effect Concentration [PEC/PNEC]), are <1.


Assuntos
Perfumes/toxicidade , Animais , Dermatite Fototóxica , Humanos , Testes de Mutagenicidade , Sistema de Registros , Medição de Risco
3.
J Cell Biol ; 145(1): 141-51, 1999 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-10189374

RESUMO

The MAL (MAL/VIP17) proteolipid is a nonglycosylated integral membrane protein expressed in a restricted pattern of cell types, including T lymphocytes, myelin-forming cells, and polarized epithelial cells. Transport of the influenza virus hemagglutinin (HA) to the apical surface of epithelial Madin-Darby canine kidney (MDCK) cells appears to be mediated by a pathway involving glycolipid- and cholesterol- enriched membranes (GEMs). In MDCK cells, MAL has been proposed previously as being an element of the protein machinery for the GEM-dependent apical transport pathway. Using an antisense oligonucleotide-based strategy and a newly generated monoclonal antibody to canine MAL, herein we have approached the effect of MAL depletion on HA transport in MDCK cells. We have found that MAL depletion diminishes the presence of HA in GEMs, reduces the rate of HA transport to the cell surface, inhibits the delivery of HA to the apical surface, and produces partial missorting of HA to the basolateral membrane. These effects were corrected by ectopic expression of MAL in MDCK cells whose endogenous MAL protein was depleted. Our results indicate that MAL is necessary for both normal apical transport and accurate sorting of HA.


Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Proteínas de Membrana Transportadoras , Proteínas da Mielina , Proteolipídeos/fisiologia , Animais , Anticorpos Monoclonais/farmacologia , Transporte Biológico/efeitos dos fármacos , Polaridade Celular , Detergentes/farmacologia , Cães , Células Epiteliais/metabolismo , Rim , Lipídeos de Membrana/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Proteolipídicas Associadas a Linfócitos e Mielina , Oligonucleotídeos Antissenso/farmacologia , Proteolipídeos/antagonistas & inibidores , Proteolipídeos/genética , Proteolipídeos/imunologia , Ratos , Ratos Wistar , Transfecção
4.
Food Chem Toxicol ; 130 Suppl 1: 110622, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31238136

RESUMO

The existing information supports the use of this material as described in this safety assessment. Methyl 2-nonenoate was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data from read-across analog ethyl trans-2,cis-4-decadienoate (CAS # 3025-30-7) show that methyl 2-nonenoate is not expected to be genotoxic. The repeated dose, reproductive, and local respiratory toxicity endpoints were evaluated using the TTC for a Cramer Class I material, and the exposure to methyl 2-nonenoate is below the TTC (0.03 mg/kg/day, 0.03 mg/kg/day, and 1.4 mg/day, respectively). Data from the target and read-across analog isobutyl-2-butenoate (CAS # 589-66-2) do not indicate the material is a sensitizer. The phototoxicity/photoallergenicity endpoints were evaluated based on data and UV spectra; methyl 2-nonenoate is not expected to be phototoxic/photoallergenic. The environmental endpoints were evaluated; methyl 2-nonenoate was found not to be PBT as per the IFRA Environmental Standards, and its risk quotients, based on its current volume of use in Europe and North America (i.e., PEC/PNEC), are <1.


Assuntos
Ácidos Graxos Monoinsaturados/química , Ácidos Graxos Monoinsaturados/toxicidade , Perfumes/química , Perfumes/toxicidade , Testes de Toxicidade/métodos , Animais , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Humanos , Estrutura Molecular , Medição de Risco
5.
Food Chem Toxicol ; 134 Suppl 2: 111024, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31812735

RESUMO

Hydroxycitronellal dimethyl acetal was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data from read-across analog hydroxycitronellal diethyl acetal (CAS # 7779-94-4) show that hydroxycitronellal dimethyl acetal is not expected to be genotoxic. The repeated dose, reproductive, and local respiratory toxicity endpoints were evaluated using the TTC for a Cramer Class I material and the exposure to hydroxycitronellal dimethyl acetal is below the TTC (0.03 mg/kg/day, 0.03 mg/kg/day, and 1.4 mg/day, respectively). Data from hydroxycitronellal dimethyl acetal and from read-across material hydroxycitronellal diethyl acetal (CAS # 7779-94-4) show that there are no safety concerns for skin sensitization under the current declared levels of use. The phototoxicity/photoallergenicity endpoints were evaluated based on UV spectra; hydroxycitronellal dimethyl acetal is not expected to be phototoxic/photoallergenic. The environmental endpoints were evaluated; hydroxycitronellal dimethyl acetal was found not to be PBT as per the IFRA Environmental Standards, and its risk quotients, based on its current volume of use in Europe and North America (i.e., PEC/PNEC), are <1.


Assuntos
Acetais/toxicidade , Octanóis/toxicidade , Odorantes , Acetais/química , Animais , Qualidade de Produtos para o Consumidor , Avaliação Pré-Clínica de Medicamentos , Determinação de Ponto Final , Escherichia coli/efeitos dos fármacos , Humanos , Testes de Mutagenicidade , Nível de Efeito Adverso não Observado , Octanóis/química , Medição de Risco , Salmonella typhimurium/efeitos dos fármacos
6.
Food Chem Toxicol ; 134 Suppl 2: 110999, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31783104

RESUMO

The existing information supports the use of this material as described in this safety assessment. Isobutyl alcohol was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data show that isobutyl alcohol is not genotoxic. Data on isobutyl alcohol provide a calculated MOE >100 for the repeated dose toxicity and reproductive toxicity endpoints. Data from read-across material isoamyl alcohol (CAS # 123-51-3) show that there are no safety concerns for isobutyl alcohol for skin sensitization under the current declared levels of use. The phototoxicity/photoallergenicity endpoints were evaluated based on UV spectra; isobutyl alcohol is not expected to be phototoxic/photoallergenic. The local respiratory toxicity endpoint was evaluated using the TTC for a Cramer Class I material and the exposure to isobutyl alcohol is below the TTC (1.4 mg/day). The environmental endpoints were evaluated; isobutyl alcohol was found not to be PBT as per the IFRA Environmental Standards, and its risk quotients, based on its current volume of use in Europe and North America (i.e., PEC/PNEC), are <1.


Assuntos
Butanóis/toxicidade , Odorantes , Animais , Butanóis/química , Qualidade de Produtos para o Consumidor , Avaliação Pré-Clínica de Medicamentos , Determinação de Ponto Final , Humanos , Testes de Mutagenicidade , Nível de Efeito Adverso não Observado , Medição de Risco , Salmonella typhimurium/efeitos dos fármacos
7.
Food Chem Toxicol ; 134 Suppl 2: 111002, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31785315

RESUMO

The existing information supports the use of this material as described in this safety assessment. p-Tolyl acetate was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data from read-across analog ethyl p-tolyl carbonate (CAS # 22719-81-9) show that p-tolyl acetate is not expected to be genotoxic. Data on read-across materials p-cresol (CAS # 106-44-5) and acetic acid (CAS # 64-19-7) provide a calculated MOE >100 for the repeated dose and reproductive toxicity endpoints. The skin sensitization endpoint was completed using DST for reactive materials (64 µg/cm2); exposure is below the DST. The phototoxicity/photoallergenicity endpoints were evaluated based on UV spectra; p-tolyl acetate is not expected to be phototoxic/photoallergenic. The local respiratory toxicity endpoint was evaluated using the TTC for a Cramer Class I material, and the exposure to p-tolyl acetate is below the TTC (1.4 mg/day).The environmental endpoints were evaluated; p-tolyl acetate was found not to be PBT as per the IFRA Environmental Standards, and its risk quotients, based on its current volume of use in Europe and North America (i.e., PEC/PNEC), are <1.


Assuntos
Cresóis/toxicidade , Odorantes , Animais , Qualidade de Produtos para o Consumidor , Cresóis/química , Avaliação Pré-Clínica de Medicamentos , Determinação de Ponto Final , Escherichia coli/efeitos dos fármacos , Humanos , Testes de Mutagenicidade , Nível de Efeito Adverso não Observado , Medição de Risco , Salmonella typhimurium/efeitos dos fármacos
8.
Mol Biol Cell ; 11(6): 2033-45, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10848627

RESUMO

The MAL proteolipid has been recently demonstrated as being necessary for correct apical sorting of the transmembrane influenza virus hemagglutinin (HA) in Madin-Darby canine kidney (MDCK) cells. The fact that, in contrast to MDCK cells, Fischer rat thyroid (FRT) cells target the majority of glycosylphosphatidylinositol (GPI)-anchored proteins to the basolateral membrane provides us with the opportunity to determine the role of MAL in apical transport of membrane proteins under conditions in which the majority of GPI-anchored proteins are (MDCK cells) or are not (FRT cells) targeted to the apical surface. Using an antisense oligonucleotide-based strategy to deplete endogenous MAL, we have observed that correct transport of apical transmembrane proteins associated (HA) or not (exogenous neurotrophin receptor and endogenous dipeptidyl peptidase IV) with lipid rafts, as well as that of the bulk of endogenous apical membrane, takes place in FRT cells by a pathway that requires normal MAL levels. Even transport of placental alkaline phosphatase, a GPI-anchored protein that is targeted apically in FRT cells, was dependent on normal MAL levels. Similarly, in addition to the reported effect of MAL on HA transport, depletion of MAL in MDCK cells caused a dramatic reduction in the apical delivery of the GPI-anchored gD1-DAF protein, neurotrophin receptor, and the bulk of membrane proteins. These results suggest that MAL is necessary for the overall apical transport of membrane proteins in polarized MDCK and FRT cells.


Assuntos
Proteínas de Membrana/metabolismo , Proteínas de Membrana Transportadoras , Proteínas da Mielina/metabolismo , Proteolipídeos/metabolismo , Animais , Transporte Biológico , Antígenos CD55/genética , Antígenos CD55/metabolismo , Linhagem Celular , Polaridade Celular , Dipeptidil Peptidase 4/metabolismo , Cães , Células Epiteliais/metabolismo , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Humanos , Proteínas de Membrana/genética , Proteínas da Mielina/genética , Proteínas Proteolipídicas Associadas a Linfócitos e Mielina , Oligonucleotídeos Antissenso , Proteolipídeos/genética , Ratos , Ratos Endogâmicos F344 , Receptores de Fator de Crescimento Neural/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Glândula Tireoide/citologia , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo
9.
Pediatr Obes ; 12(6): 446-452, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-27350543

RESUMO

BACKGROUND: Gut-liver axis (GLA) dysfunction appears to play a role in obesity and obesity-related hepatic complications. OBJECTIVES: This study sought to concurrently explore several GLA components in a paediatric obese population with/without liver disease. METHODS: Thirty-two children (mean age 11.2 years) were enrolled: nine controls with normal weight and 23 patients with obesity (OB+). Of the 23 patients OB(+), 12 had not steatosis (ST-), and 11 had steatosis (ST+) (associated [n = 8] or not [n = 3] with hypertransaminasaemia [ALT +/-]). Subjects were characterized by using auxologic, ultrasonographic and laboratory parameters. A glucose hydrogen breath test was performed to test for small intestinal bacterial overgrowth, a urinary lactulose/mannitol ratio (LMR) was obtained to assess intestinal permeability, and tests for transaminases, blood endogenous ethanol, endotoxin and faecal calprotectin were also conducted. RESULTS: Eleven out of 23 patients OB(+) (p < 0.05) exhibited pathological (>90th percentile of the control group values) LMR, with values paralleling the grade of liver involvement (normal weight < OB[+] < OB[+]ST[+]ALT[-] < OB[+)]ST[+]ALT[+] [p < 0.05]). LMR significantly correlated with ethanolaemia (r = 0.38, p = 0.05) and endotoxaemia (r = 0.48, p = 0.015) concentrations. Increased permeability was a risk factor for the development of steatosis (p < 0.002). SIBO was present only in patients with obesity. Faecal calprotectin concentrations were within normal limits in all subjects. CONCLUSIONS: Increased permeability, endogenous ethanol and systemic endotoxin concentrations reflect some GLA dysfunction in obesity and its hepatic complications. Pending further results to establish their potential causative roles, the modulation of the GLA appears to represent a possible target for the prevention and treatment of these conditions.


Assuntos
Intestinos/fisiopatologia , Hepatopatias/etiologia , Fígado/patologia , Obesidade Infantil/fisiopatologia , Adolescente , Testes Respiratórios , Criança , Feminino , Humanos , Testes de Função Hepática , Masculino , Obesidade Infantil/complicações , Permeabilidade , Fatores de Risco
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA