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1.
Biomed Environ Sci ; 34(8): 606-615, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34474720

RESUMO

Objective: This study aimed to assess the risk of cumulative exposure to Pb, Cd, Hg, and iAs through aquatic products consumed by Chinese people. Methods: Heavy metal concentration data were obtained from the national food contamination monitoring program during 2013-2017. Consumption data were derived from the China National Food Consumption Survey in 2014 and the relative potency factor (RPF) method was used to estimate cumulative exposure for neurotoxicity and nephrotoxicity. Results: The results demonstrated that the cumulative exposure based on neurotoxicity was below the lower confidence limit on benchmark doses of lead (BMDL 01) for nephrotoxicity and the cumulative exposures were all lower than the provisional tolerable monthly intake (PTMI) of Cd. However, the margin of exposure values (MOEs) of the cumulative exposures for neurotoxicity in the 2-6 year-old group was close to 1 and the cumulative exposure level for nephrotoxicity accounted for 90.21 % of the PTMI. Conclusion: The cumulative exposures of the 2-6 year-old group to the four heavy metals did not reach (but came close to) the corresponding safety threshold for both neurotoxicity and nephrotoxicity. Given that there are still other food sources of these four heavy metals, it is necessary to more closely study their cumulative health effects.


Assuntos
Arsênio/análise , Exposição Dietética/análise , Contaminação de Alimentos/análise , Metais Pesados/análise , Alimentos Marinhos/análise , Poluentes Químicos da Água/análise , Adolescente , Adulto , Idoso , Animais , Criança , Pré-Escolar , Monitoramento Ambiental , Humanos , Pessoa de Meia-Idade , Medição de Risco , Adulto Jovem
2.
Artigo em Inglês | MEDLINE | ID: mdl-30650034

RESUMO

Morpholine is a common chemical used as emulsifier in the preparation of wax coatings for some fruit to help them remain fresh and protect against insects and fungal contamination. It has been reported that morpholine has acute toxic effects on rodents. In the present study, morpholine concentrations were analysed in fruits (citrus fruits, apples, strawberries and grapes) and juices (apple juice and orange juice) in order to determine dietary exposure among the Chinese population. A total of 732 fruit and juice samples were collected during 2015-2016, which covered major foods in China. Fruit and juice consumption data were taken from China National Nutrient and Health Survey (2002) and include data from 16,407 fruit or juice consumers. It was found that mean dietary exposure to morpholine residues from fruits and/or juices for general Chinese consumers and children 2-6 years old were 0.42 and 1.24 µg/kg bw/day, respectively. The 97.5% intake in general Chinese consumers and children 2-6 years old were 2.25 and 6.90 µg/kg bw/day, respectively. The primary food sources of the morpholine dietary intake of general Chinese consumers were citrus fruits (57.4%) and apples (40.8%). These findings suggested that dietary exposure to morpholine in the Chinese population was lower than the acceptable daily intake of morpholine, and there are no health concerns.


Assuntos
Dieta/estatística & dados numéricos , Exposição Dietética , Contaminação de Alimentos/análise , Sucos de Frutas e Vegetais/análise , Frutas/química , Morfolinas/análise , China
3.
Molecules ; 23(2)2018 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-29466304

RESUMO

Lewis pair polymerization is a powerful method for preparing soluble polymers bearing pendant active vinyl groups by directly polymerizing dissymmetric divinyl polar monomers. Herein, we present a strategy for synthesizing block and brush copolymers via tandem Lewis pair polymerization of methacrylates, "thiol-ene" click reaction and organocatalytic ring-opening polymerization of lactide.


Assuntos
Ácidos de Lewis/química , Bases de Lewis/química , Polimerização , Polímeros/química , Polímeros/síntese química , Catálise , Cromatografia em Gel , Poliésteres/síntese química , Poliésteres/química , Polimetil Metacrilato/síntese química , Polimetil Metacrilato/química , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray
4.
Ultrason Sonochem ; 22: 144-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24974005

RESUMO

4-Substituted 1,4-dihydropyridine-3,5-dicarboxylates (4) have been synthesized by the solvent-free reaction of aldehyde, methyl propiolate and ammonium carbonate catalyzed by ionic liquid 1-carboxymethyl-3-methylimidazolium tetrafluoroborate under ultrasonic irradiation. The effects of changes in the ultrasonic power, temperature, catalysts and reactants on the synthesis of 4-substituted 1,4-dihydropyridine-3,5-dicarboxylates (4) are discussed. With the optimized reaction conditions, various aldehydes were used to synthesize 1,4-dihydropyridines (4) under the influence of ultrasound irradiation. Compared with the conventional thermal methods, the remarkable advantages of this method are the simple experimental procedure, shorter reaction time (2-10min) and high yield of product (76-95%). Furthermore, the green catalytic system can be recycled specific times without significantly decreasing the yields and reaction rates.

5.
Molecules ; 19(11): 19050-65, 2014 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-25415471

RESUMO

Several pleuromutilin derivatives possessing thiadiazole moieties were synthesized via acylation reactions under mild conditions. The in vitro antibacterial activities of the derivatives against methicillin-resistant S. aureus, methicillin-resistant S. epidermidis, S. aureus, S. epidermidis, E. coli, and B. cereus were tested by the agar dilution method and Oxford cup assay. All the screened compounds displayed potent activity. Compound 6d was the most active antibacterial agent because of its lowest MIC value and largest inhibition zone. Docking experiments were performed to understand the possible mode of the interactions between the derivatives and 50S ribosomal subunit. Moreover, the absorption, distribution, metabolism, excretion and toxicity properties of the synthesized compounds were analyzed after prediction using the Advanced Chemistry Development/Percepta Platform available online.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Diterpenos/síntese química , Diterpenos/farmacologia , Testes de Sensibilidade Microbiana/métodos , Simulação de Acoplamento Molecular , Compostos Policíclicos
6.
Chem Biol Interact ; 213: 21-7, 2014 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-24480521

RESUMO

Translocation of viral integrase (IN) into the nucleus is a critical precondition of integration during the life cycle of HIV, a causative agent of Acquired Immunodeficiency Syndromes (AIDS). As the first discovered cellular factor to interact with IN, Lens epithelium-derived growth factor (LEDGF/p75) plays an important role in the process of integration. Disruption of the LEDGF/p75-IN interaction has provided a great interest for anti-HIV agent discovery. In this work, we reported that one small molecular compound, 1,4-bis(5-(naphthalen-1-yl)thiophen-2-yl)naphthalene(Compound 15), potently inhibit the IN-LEDGF/p75 interaction and affect the HIV-1 IN nuclear distribution at 1 µM. The putative binding mode of Compound 15 was constructed by a molecular docking simulation to provide structural insights into the ligand-binding mechanism. Compound 15 suppressed viral replication by measuring p24 antigen production in HIV-1IIIB acute infected C8166 cells with EC50 value of 11.19 µM. Compound 15 might supply useful structural information for further anti-HIV agent discovery.


Assuntos
Inibidores de Integrase de HIV/farmacologia , Integrase de HIV/metabolismo , HIV-1/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Naftalenos/química , Tiofenos/química , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Sistemas de Liberação de Medicamentos , Integrase de HIV/química , Inibidores de Integrase de HIV/química , Humanos , Concentração Inibidora 50 , Peptídeos e Proteínas de Sinalização Intercelular/química , Modelos Moleculares , Simulação de Acoplamento Molecular , Naftalenos/farmacologia , Bibliotecas de Moléculas Pequenas , Tiofenos/farmacologia , Replicação Viral/efeitos dos fármacos
7.
Mol Med Rep ; 4(1): 181-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21461583

RESUMO

Several studies have investigated whether the CCR2-Val64Ile polymorphism affects susceptibility to human immune deficiency virus type-1 (HIV-1), with inconclusive results. Here, we performed a meta-analysis of the literature aiming to clarify the relationship between the polymorphism of CCR2-Val64Ile and the risk of HIV-1 infection. Twelve studies with a total of 6,599 patients, including infants, were selected for inclusion in the analysis. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were assessed after the collected data were pooled for analysis. The risk estimates (OR) of HIV-1 infection were calculated in a homozygote comparison (OR=1.10, 95% CI 0.79-1.53), a heterozygote comparison (OR=0.98, 95% CI 0.70-1.37), a dominant model (OR=1.06, 95% CI 0.77-1.47) and a recessive model (OR=0.98, 95% CI 0.77-1.27, by random effects model) from among the total population. Taking into account the effect of sample size, ethnicity and control population, further stratified analyses were performed. The results showed no statistically significant difference in any genetic model, with the exception of the sub-analysis of mixed ethnicity (OR=0.33, 95% CI 0.11­0.98) using heterozygote comparison. The meta-analysis clarified that the CCR2-Val64Ile polymorphism has no effect on susceptibility to HIV-1 infection in the total population.


Assuntos
Predisposição Genética para Doença , Infecções por HIV/genética , Receptores CCR2/genética , Infecções por HIV/epidemiologia , Humanos , Medição de Risco , Fatores de Risco
8.
Arch Pharm Res ; 33(10): 1641-9, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21052939

RESUMO

Acetylcholinesterase (AChE) inhibitors played an important role in developing a cure for Alzheimer' s disease. In order to study on the influence of modifications at different groups and side chains on the AChE inhibitory ability and the active sites of 7H-thiazolo[3,2-b][1,2,4]triazin-7-one derivatives, fourteen 3,6-diaryl-7H-thiazolo[3,2-b][1,2,4]triazin-7-one derivatives were designed and synthesized. The study of AChE inhibitory activity was carried out using the Ellman colorimetric assay with huperzine-A as the positive control drug. Most of the target compounds exhibited more than 50% inhibition at 10 µM. Some target compounds showed strong inhibition against AChE. The molecular fields analysis and preliminary structure-activity relationships are discussed.


Assuntos
Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/farmacologia , Doença de Alzheimer/tratamento farmacológico , Animais , Sítios de Ligação , Inibidores da Colinesterase/química , Inibidores da Colinesterase/metabolismo , Bases de Dados de Proteínas , Proteínas Ligadas por GPI/antagonistas & inibidores , Proteínas Ligadas por GPI/química , Proteínas Ligadas por GPI/metabolismo , Humanos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular , Ligação Proteica , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Infravermelho , Relação Estrutura-Atividade , Tiazóis/química , Torpedo/metabolismo , Triazinas/química
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