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1.
Food Res Int ; 190: 114633, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38945584

RESUMO

The Frankfurter sausages smoked with beech, oak, and alder, respectively, were used to clarify the underlying impact of the smoke chemical composition on the levels of heterocyclic amines (HAs) and polycyclic aromatic hydrocarbons (PAHs). The result indicated that different wood types significantly affected the profiles of target substances in food matrices. The beech-smoked samples had lower contents of total free HAs (5.98-6.80 ng/g dry-weight-DW), PAH4 (3.31-3.83 ng/g DW), and PAH8 (10.0-10.8 ng/g DW), whereas the alder pyrolysis usually led to higher hazardous residues (8.26-9.19 ng/g DW of total free HAs, 4.24-6.60 ng/g DW of PAH4 and 14.1-23.3 ng/g DW of PAH8). In addition, the differences in smoke chemical composition were attributed to the different proportions of 15 key identified substances. Among them, two aldehydes (5-methyl-furfural & furfural) and two phenols (phenol & 5-hydroxymaltol) may have synergistic or competitive inhibitory effects on the formation of HAs and PAHs in smoked meat products.


Assuntos
Aminas , Produtos da Carne , Hidrocarbonetos Policíclicos Aromáticos , Fumaça , Madeira , Hidrocarbonetos Policíclicos Aromáticos/análise , Produtos da Carne/análise , Fumaça/análise , Madeira/química , Aminas/análise , Compostos Heterocíclicos/análise , Contaminação de Alimentos/análise , Animais
2.
Food Chem ; 423: 136258, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37172502

RESUMO

The impact of temperature-controlled smoldering smoking conditions on the accumulations of polycyclic aromatic hydrocarbons (PAHs) and heterocyclic amines (HAs) in Frankfurter-type sausages was investigated. Depending on the temperature, smoking can be divided into two phases: an unstable pyrolysis stage (≈ 200 s) and a stable pyrolysis stage (>200 s), which had different effects on hazardous substances contents. The unstable pyrolysis stage, which contributed 66.9 âˆ¼ 89.6% of PAH accumulations by comparing with sausages smoked for 15 min, has significant impact on high PAH residues. By contrast, the contents of HAs showed steady increase trends with smoking time. Few types of free-HAs with low concentrations (3.05 âˆ¼ 22.9 ng/g DW), but more types of bound-HAs with much higher levels (10.8 âˆ¼ 396 ng/g DW) were found. In addition, the formation of some HAs followed the first-order reaction model. However, the detailed formation mechanisms of PAHs and HAs under temperature-controlled smoldering smoking conditions remain to be studied.


Assuntos
Produtos da Carne , Hidrocarbonetos Policíclicos Aromáticos , Hidrocarbonetos Policíclicos Aromáticos/química , Temperatura , Produtos da Carne/análise , Aminas , Fumar
3.
Huan Jing Ke Xue ; 42(2): 749-760, 2021 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-33742869

RESUMO

Emerging contaminants including antibiotics and antibiotic resistance genes (ARGs) have been frequently detected in drinking water resources. In this study, the occurrence of antibiotics and ARGs in various environmental matrices in representative drinking water sources in Jiangsu Province and their influencing factors were explored. Five representative drinking water sources in northern, central, and southern Jiangsu were selected. Water, surface sediment, and epilithic biofilm samples were harvested near the water intakes of each water resource in December 2018 and June 2019. The concentrations and abundances of ten antibiotics, one integrase gene intl1, and seven common ARGs were measured. The results suggest that the concentrations of the target antibiotics and ARGs are relatively low compared to previously reported data in China and elsewhere in the world. The target antibiotics were detected in all of the water sources. The concentrations of sulfonamides in the water, surface sediment, and epilithic biofilm ranged from not found (NF) to 37.4 ng·L-1, NF to 47.3 ng·g-1, and NF to 3759.1 ng·g-1, respectively; the concentrations of quinolones in three matrices were NF-5.3 ng·L-1, 0.4-32.5 ng·g-1, and NF-4220.9 ng·g-1, respectively. The detection rates of the ARGs including sul 1, sul2, tetW, and tetQ were 100%, among which the sulfonamides sul1 and sul2 showed the highest abundance. The absolute abundances of sul1 in the three matrices were 2.48×106 copies·L-1, 3.54×107 copies·g-1, and 1.44×109 copies·g-1, respectively. The abundances of ARGs in the sediments and epilithic biofilms were comparable, and were much higher than in the water body. The phyla Bacteroidetes, Proteobacteris, Firmicutes, Verrucobacteria, and Actinomycetes have proven potential hosts for ARGs and might play an important role in the transmission and diffusion of resistance genes. This study offers baseline information on the presence of antibiotics and ARGs in the drinking water sources of Jiangsu Province, providing a significant theoretical basis for ARGs pollution control and safety guidelines for drinking water resources.


Assuntos
Antibacterianos , Água Potável , Antibacterianos/análise , China , Água Potável/análise , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos/genética , Recursos Hídricos
4.
Biol Pharm Bull ; 34(10): 1527-32, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21963491

RESUMO

Gq-protein is located at the convergent point in signal transduction pathways leading to vascular remodeling. The carboxyl terminus of Gα-subunit plays a vital role in G-protein-receptor interaction. The present study was designed to explore the effects of a synthetic Gαq carboxyl terminus imitation peptide, namely GCIP-27, on vascular smooth muscle cells (VSMC) in vitro and vascular remodeling in spontaneous hypertensive rats (SHR). Hyperplasia and hypertrophy of VSMC wre determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, [(3)H]-thymidine and [(3)H]-leucine incorporation, and [Ca(2+)](i) was measured with Fluo-3/AM staining. Systolic blood pressure (SBP), the ratio of media thickness to lumen diameter (MT/LD) of aorta, collagen content, and phospholipase C activity in aorta were measured in SHR. GCIP-27 (3-100 µg/l) significantly decreased proliferation activity, protein content, incorporation of [(3)H]-thymidine and [(3)H]-leucine, and [Ca(2+)](i) level in VSMC. SBP, MT/LD, collagen content, and phospholipase C activity in aorta of SHR were decreased significantly in GCIP-27 (7, 20, 60 µg/kg)-treated groups and losartan (6 mg/kg) group compared with vehicle group. In conclusion, GCIP-27 could inhibit vascular remodeling effectively in vitro and in vivo.


Assuntos
Aorta/patologia , Cardiotônicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/uso terapêutico , Hipertensão/patologia , Hipertrofia/patologia , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/patologia , Peptídeos/farmacologia , Células 3T3 , Angiotensina II/farmacologia , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Animais , Aorta/citologia , Aorta/metabolismo , Aorta/fisiopatologia , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Determinação da Pressão Arterial , Cálcio/análise , Cardiotônicos/uso terapêutico , Técnicas de Cultura de Células , Colágeno/metabolismo , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/fisiologia , Hipertensão/tratamento farmacológico , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Hipertrofia/fisiopatologia , Losartan/farmacologia , Masculino , Camundongos , Terapia de Alvo Molecular , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/metabolismo , Distribuição Aleatória , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Ratos Wistar , Sais de Tetrazólio , Tiazóis , Fosfolipases Tipo C/metabolismo , Vasoconstritores/farmacologia
6.
Clin Exp Pharmacol Physiol ; 35(10): 1215-21, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18518877

RESUMO

The G(q)-protein is located at the convergent point in the signal transduction pathway that leads to ventricular remodelling. In G-protein signalling pathways, the carboxyl terminus of the G(alpha)-subunit plays a vital role in G-protein-receptor interaction. The aim of the present study was to explore the effects of a synthetic G(alphaq) carboxyl terminus imitation peptide, namely GCIP-27, on left ventricular (LV) remodelling and blood pressure in spontaneous hypertensive rats (SHR). In the present study, 10, 30 or 90 microg/kg, i.p., GCIP-27 was administered for 8 weeks to SHR. In addition, another two groups of SHR were treated with either 6 mg/kg losartan or vehicle (saline). Wistar-Kyoto rats were used as controls. Systolic blood pressure (SBP) was measured using the standard tail-cuff method once every 2 weeks. At the end of the experiment, the LV mass index (LVMI) was evaluated. In addition, LV structure and function, collagen content, microstructure and ultrastructure were examined using echocardiography, the hydroxyproline assay, routine light microscopy and transmission electron microscopy, respectively. In the losartan- and GCIP-27 (10, 30 and 90 microg/kg)-treated groups, SBP was decreased significantly compared with that of the vehicle (saline) group. However, even at the highest concentration used, the hypotensive effect of GCIP-27 was weaker than that of losartan. For example, after 8 weeks treatment, SBP had decreased by 30.4% in the losartan-treated group compared with decreases of 10.5, 13.1 and 18.5% in the 10, 30 and 90 microg/kg GCIP-27-treated groups, respectively. Both GCIP-27 (10, 30 and 90 microg/kg) and losartan (6 mg/kg) significantly reduced LV posterior wall thickness, the thickness of the interventricular septum, collagen content and LVMI, with the effects of GCIP-27 at all three concentrations tested being greater than those of losartan. In conclusion, GCIP-27 effectively attenuates LV remodelling in SHR and the antiremodelling effect may not be dependent entirely on decreases in blood pressure.


Assuntos
Pressão Sanguínea/fisiologia , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/síntese química , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/uso terapêutico , Proteínas de Ligação ao GTP/síntese química , Proteínas de Ligação ao GTP/uso terapêutico , Mimetismo Molecular/fisiologia , Fragmentos de Peptídeos/uso terapêutico , Remodelação Ventricular/fisiologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Hipertensão/patologia , Hipertensão/fisiopatologia , Masculino , Fragmentos de Peptídeos/síntese química , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Remodelação Ventricular/efeitos dos fármacos
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