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1.
Food Chem Toxicol ; 188: 114655, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38614221

RESUMO

The special issue "New Insight into Mycotoxins and Bacterial Toxins: Toxicity Assessment, Molecular Mechanism and Food Safety" in Food and Chemical Toxicology contains 19 articles on current hot topics in mycotoxins and bacterial toxins. Dietary exposure to mycotoxins and risk assessments are reported in this issue. Molecular mechanisms of multiple mycotoxins and emerging mechanisms of toxicity are especially concerned by researchers. Moreover, mycotoxin-detoxifying substances and antimicrobial agents are also fully investigated in the context. This special issue will help to further understand the mycotoxins and bacterial toxins, casting new light for the control of food safety.


Assuntos
Toxinas Bacterianas , Inocuidade dos Alimentos , Micotoxinas , Micotoxinas/toxicidade , Micotoxinas/análise , Toxinas Bacterianas/toxicidade , Humanos , Contaminação de Alimentos/análise , Animais , Medição de Risco
2.
Br J Radiol ; 96(1149): 20200448, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37393533

RESUMO

OBJECTIVE: The study explores the application value of three-dimensional arterial spin labeling magnetic resonance imaging (3D pCASL) in early assessment of radiation encephalopathy (REP) in patients with nasopharyngeal carcinoma (NPC). METHODS: A retrospective analysis of 39 cases of NPC was performed. Routine enhanced MRI scan and 3D pCASL imaging were used to examine the apparent diffusion coefficient (ADC) and brain blood flow (CBF) before and after treatment with intensity-modulated radiotherapy (IMRT). Dosimetric analysis of irradiation was performed. Receiver operating characteristic curve (ROC) was used to analyze diagnostic performance of two imaging methods. RESULTS: There was no statistically significant difference between the two methods for the measurement of temporal white matter ADC, but statistically significant difference was found in CBF. 3D pCASL imaging showed more sensitivity, specificity and higher accuracy than conventional MRI enhanced scan in showing REP. The maximum dose of the temporal lobe was at the enhanced area. CONCLUSION: The present study demonstrates that 3D pCASL scan at month 3 can reflect blood flow perfusion differences in NPC patients after IMRT and can accurately assess the possibility of REP at early stage. Enhanced areas have a higher probability of REP than the surrounding areas. ADVANCES IN KNOWLEDGE: There is few magnetic resonance angiography studies used to evaluate arterial circulation on its application on potential REP after radiotherapy for NPC. In our study, we evaluate the application value of 3D pCASL in the early assessment of potential REP in patients with NPC after radiotherapy. The study was to provide an improved understanding of the early specific characteristics on MRI imaging and evolution of potential radiation encephalopathy using 3D pCASL technique, which can quantitatively evaluate the changes of blood flow in tissues at early stage and help to diagnose and treat potential radiation encephalopathy as early as possible.


Assuntos
Encefalopatias , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/diagnóstico por imagem , Carcinoma Nasofaríngeo/radioterapia , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Circulação Cerebrovascular , Neoplasias Nasofaríngeas/diagnóstico por imagem , Neoplasias Nasofaríngeas/radioterapia , Marcadores de Spin
3.
Toxicology ; 492: 153549, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37209941

RESUMO

Serious health risks associated with the consumption of food products contaminated with aflatoxins (AFs) are worldwide recognized and depend predominantly on consumed AF concentration by diet. A low concentration of aflatoxins in cereals and related food commodities is unavoidable, especially in subtropic and tropic regions. Accordingly, risk assessment guidelines established by regulatory bodies in different countries help in the prevention of aflatoxin intoxication and the protection of public health. By assessing the maximal levels of aflatoxins in food products which are a potential risk to human health, it's possible to establish appropriate risk management strategies. Regarding, a few factors are crucial for making a rational risk management decision, such as toxicological profile, adequate information concerning the exposure duration, availability of routine and some novel analytical techniques, socioeconomic factors, food intake patterns, and maximal allowed levels of each aflatoxin in different food products which may be varied between countries.


Assuntos
Aflatoxinas , Contaminação de Alimentos , Humanos , Contaminação de Alimentos/prevenção & controle , Aflatoxinas/toxicidade , Aflatoxinas/análise , Aflatoxinas/metabolismo , Dieta , Medição de Risco , Alimentos
4.
J Pharm Biomed Anal ; 227: 115277, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36736110

RESUMO

The quality of traditional Chinese medicine (TCM) guarantees its clinical efficacy. Although advanced analytical techniques and methods can accurately determine the content of chemical components in TCM, it is difficult to accurately determine its clinical efficacy. In addition, the current analytical methods and technologies are complex and have difficulty meeting the requirements of a rapid, accurate and convenient determination of TCM quality. In this study, we first propose the concept of "indistinct" evaluation of the quality of TCM, that is, combining biological potency with character evaluation, quantifying the character evaluation, and preparing the safflower quality grade evaluation card based on the character analysis, which provides research ideas and methods for the rapid and accurate evaluation of the quality of TCM. We determined the biological potency of different batches of safflower based on the in vitro antiplatelet aggregation model and divided the safflower samples into two grades based on the biological potency. We further collected the color information of different grades of safflower samples, quantified the color information of different grades of safflower, drew a quality grade evaluation card for the rapid judgment of safflower quality grade and verified its accuracy by pharmacodynamic evaluation. To further analyze the differences in the material basis of different grades of safflower, the LC-MS method was used to simultaneously determine the contents of 19 chemical components, such as myricetin, in different grades of safflower samples to analyze the differences in the material basis of different grades of safflower. The result shows that the different grades of safflower exhibited significant differences in color. The pharmacodynamic results show that the quality evaluation card prepared based on color information can accurately evaluate quality, and the effect of first-class safflower is significantly better than that of second-class safflower. The chemical analysis results of different grades of safflower show that there are also significant differences between them, among which hypericin, 6-hydroxyapin-6-O-glucose-7-O-glucuronide, 6-hydroxykaempferol-3,6-O-diglucoside-7-O-glucuronic acid glycoside, 6-hydroxykaempferol-3,6,7-tri-O-glucoside and hydroxysafflower yellow A exhibit significant differences, which may be the main differentiating components of different grades of safflower. This study preliminarily confirmed that the "indistinct" evaluation of the quality of TCM based on character analysis is accurate and scientific, and the quality evaluation card prepared can accurately judge the quality of TCM, providing a reference for the rapid application of TCM character evaluation.


Assuntos
Carthamus tinctorius , Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Carthamus tinctorius/química , Medicina de Precisão , Medicamentos de Ervas Chinesas/química , Cromatografia Líquida
5.
Environ Sci Pollut Res Int ; 30(8): 22063-22077, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36280633

RESUMO

Seawater intrusion is a common groundwater pollution problem, which has a great impact on ecological environment and economic development. In this paper, a numerical simulation model of variable density groundwater was constructed to simulate and predict the future seawater intrusion in Longkou city, Shandong Province of China. The influence of the sensitive parameter uncertainty of the model on the simulation results was evaluated by using the Monte Carlo method. In order to reduce the computational load from repeatedly calling the simulation model, the surrogate model was established by using the support vector regression (SVR) method. After training, the correlation coefficient R2 of the input-output relationship between the SVR surrogate model and the seawater intrusion simulation model reached 0.9957, with an average relative error of 0.2%, indicating that the surrogate model has a high fitting accuracy. Stochastic simulations of seawater intrusion showed that the seawater intrusion in the Longkou area will gradually aggravate at a slow rate, and the increase of seawater intrusion in the study area after 30 years was expected to range from - 6.03% to 7.37% at the 80% confidence level.


Assuntos
Água Subterrânea , Água do Mar , Método de Monte Carlo , Simulação por Computador , China , Monitoramento Ambiental
6.
Radiol Cardiothorac Imaging ; 5(6): e230064, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38166346

RESUMO

Purpose To develop a new coronary CT angiography (CCTA)-based index, α×LL/MLD4, that considers lesion entrance angle (α) in addition to lesion length (LL) and minimal lumen diameter (MLD) and to evaluate its efficacy in predicting hemodynamically significant coronary stenosis compared with invasive coronary angiography (ICA)-derived fractional flow reserve (FFR). Materials and Methods This prospective study enrolled participants (September 2016-March 2020) from two centers who underwent CCTA followed by ICA (ClinicalTrials.gov identifier: NCT03054324). CCTA images were processed semiautomatically to measure LL, MLD, and α for calculating α×LL/MLD4. Diagnostic performance and accuracy of α×LL/MLD4 and LL/MLD4 in detecting hemodynamically significant coronary stenosis were compared against the reference standard (invasive FFR ≤ 0.80). Results In total, 133 participants (mean age, 63 years ± 9 [SD]; 99 [74%] men) with 210 stenosed coronary arteries were analyzed. Median α×LL/MLD4 was 54.0 degree/mm3 (IQR, 25.3-128.7) in participants with invasive FFR of 0.80 or less and 6.7 degree/mm3 (IQR, 3.3-12.8) in participants with invasive FFR of more than 0.80 (P < .001). The per-vessel accuracy, sensitivity, specificity, positive predictive value, and negative predictive value for discriminating ischemic lesions were 86.2%, 83.1%, 88.4%, 84.1%, and 87.7% for α×LL/MLD4 and 80.5%, 66.3%, 90.9%, 84.3%, and 78.6% for LL/MLD4, respectively. Area under the receiver operating characteristic curve for discriminating hemodynamically significant stenosis was 0.93 for α×LL/MLD4, which was significantly greater than the values of 0.84 for LL/MLD4 and 0.63 for diameter stenosis (both P < .001). Conclusion The new morphologic index, α×LL/MLD4, incorporating lesion entrance angle achieved higher diagnostic performance in detecting hemodynamically significant lesions compared with diameter stenosis and LL/MLD4. Keywords: CT Angiography, Cardiac, Coronary Arteries, Ischemia, Infarction, Technology Assessment Clinical trial registration no. NCT03054324 Supplemental material is available for this article. © RSNA, 2023 See also the commentary by Fairbairn and Nørgaard in this issue.


Assuntos
Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Angiografia por Tomografia Computadorizada/métodos , Constrição Patológica , Angiografia Coronária/métodos , Estenose Coronária/diagnóstico , Estudos Prospectivos , Estudos Retrospectivos , Idoso
7.
Int J Cardiol ; 348: 9-14, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34864078

RESUMO

BACKGROUND: Physician visual assessment (PVA) in invasive coronary angiography (ICA) is the current clinical method to determine stenosis severity and guide percutaneous coronary intervention. This study sought to evaluate the effect of sex differences in assessing coronary stenosis severity between PVA and quantitative coronary angiography (QCA). METHODS: 209 patients with coronary artery disease (288 coronary lesions) underwent ICA and fractional flow reserve (FFR). ICA image processing including PVA and QCA was used to quantify diameter stenosis (DS). The difference of DS (ΔDS) between PVA and QCA was defined as DSPVA-DSQCA. DS ≥50% was considered anatomically obstructive. FFR ≤0.8 was defined as myocardial ischemia. RESULTS: Mean ± SD age was 63 ± 9 years. There were no significant differences in DSPVA (61.1 ± 16.3% vs 60.1 ± 18.9%) and DSQCA (53.1 ± 12.1% vs 55.4 ± 14.3%) between females and males. However, ΔDS between PVA and QCA was higher in females (8.0 ± 10.9%) than in males (4.7 ± 10.9%) (P = 0.03). Thirty-four of 72 vessels (47.2%) in female patients and 75 of 216 vessels (34.7%) in male patients were classified differently by at least one grade using PVA compared to QCA assessment. DSPVA and DSQCA were negatively correlated with FFR in females (rPVA = -0.397, rQCA = -0.448) with an even stronger negative correlation in males (rPVA = -0.607, rQCA = -0.607). ROC analysis demonstrated that DSQCA had better discrimination capability for myocardial ischemia (FFR ≤ 0.80) than DSPVA in both sexes (P < 0.05). CONCLUSIONS: A systematic bias was found in PVA (QCA reference) for overestimating severity of coronary artery disease in females compared to males.


Assuntos
Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Médicos , Idoso , Constrição Patológica , Angiografia Coronária , Estenose Coronária/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Índice de Gravidade de Doença , Caracteres Sexuais
8.
Arch Toxicol ; 94(11): 3645-3669, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32910237

RESUMO

T-2 toxin is the most toxic trichothecene mycotoxin, and it exerts potent toxic effects, including immunotoxicity, neurotoxicity, and reproductive toxicity. Recently, several novel metabolites, including 3',4'-dihydroxy-T-2 toxin and 4',4'-dihydroxy-T-2 toxin, have been uncovered. The enzymes CYP3A4 and carboxylesterase contribute to T-2 toxin metabolism, with 3'-hydroxy-T-2 toxin and HT-2 toxin as the corresponding primary products. Modified forms of T-2 toxin, including T-2-3-glucoside, exert their immunotoxic effects by signaling through JAK/STAT but not MAPK. T-2-3-glucoside results from hydrolyzation of the corresponding parent mycotoxin and other metabolites by the intestinal microbiota, which leads to enhanced toxicity. Increasing evidence has shown that autophagy, hypoxia-inducible factors, and exosomes are involved in T-2 toxin-induced immunotoxicity. Autophagy promotes the immunosuppression induced by T-2 toxin, and a complex crosstalk between apoptosis and autophagy exists. Very recently, "immune evasion" activity was reported to be associated with this toxin; this activity is initiated inside cells and allows pathogens to escape the host immune response. Moreover, T-2 toxin has the potential to trigger hypoxia in cells, which is related to activation of hypoxia-inducible factor and the release of exosomes, leading to immunotoxicity. Based on the data from a series of human exposure studies, free T-2 toxin, HT-2 toxin, and HT-2-4-glucuronide should be considered human T-2 toxin biomarkers in the urine. The present review focuses on novel findings related to the metabolism, immunotoxicity, and human exposure assessment of T-2 toxin and its modified forms. In particular, the immunotoxicity mechanisms of T-2 toxin and the toxicity mechanism of its modified form, as well as human T-2 toxin biomarkers, are discussed. This work will contribute to an improved understanding of the immunotoxicity mechanism of T-2 toxin and its modified forms.


Assuntos
Exposição Ambiental/análise , Toxina T-2/metabolismo , Toxina T-2/toxicidade , Animais , Apoptose , Autofagia , Biomarcadores , Hipóxia Celular , Humanos , Transdução de Sinais , Toxina T-2/análogos & derivados
9.
Artigo em Inglês | MEDLINE | ID: mdl-31546849

RESUMO

The development of rural infrastructure plays an essential role in improving rural livelihoods and enhancing sustainable and environmentally friendly agricultural production. However, little is known about whether rural infrastructure enables the promotion of resource-conserving agriculture and reduces production costs. Understanding the relationship between rural infrastructure and production costs can provide significant information for policy-makers in their efforts to promote resource-saving agriculture that is beneficial to environmental performance. This study contributes to the literature by analyzing the heterogeneous effects of irrigation infrastructure and standard and substandard roads on agricultural production costs, using an unconditional quantile regression model and provincial data from China for the period 1995-2017. The empirical results show that the effects of rural infrastructure on production costs are mixed. In particular, irrigation infrastructure affects production costs positively in the lower quantiles, but it negatively affects production costs in the higher quantiles. In the higher 80th and 90th quantiles, standard and substandard roads affect production costs both negatively and significantly. Our findings suggest that improving rural infrastructure enables the promotion of resource-conserving agriculture and enhances environmental performance, especially for those paying high production costs.


Assuntos
Irrigação Agrícola , Conservação dos Recursos Naturais , Produção Agrícola/economia , Modelos Econômicos , Meios de Transporte , Agricultura , China , Humanos , População Rural
10.
Mini Rev Med Chem ; 19(3): 206-214, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30264680

RESUMO

Beauvericin (BEA) is a cyclic hexadepsipeptide, which derives from Cordyceps cicadae. It is also produced by Fusarium species, which are parasitic to maize, wheat, rice and other important commodities. BEA increases ion permeability in biological membranes by forming a complex with essential cations, which may affect ionic homeostasis. Its ion-complexing capability allows BEA to transport alkaline earth metal and alkali metal ions across cell membranes. Importantly, increasing lines of evidence show that BEA has an anticancer effect and can be potentially used in cancer therapeutics. Normally, BEA performs the anticancer effect due to the induced cancer cell apoptosis via a reactive oxygen species-dependent pathway. Moreover, BEA increases the intracellular Ca2+ levels and subsequently regulates the activity of a series of signalling pathways including MAPK, JAK/STAT, and NF-κB, and finally causes cancer cell apoptosis. In vivo studies further show that BEA reduces tumour volumes and weights. BEA especially targets differentiated and invasive cancer types. Currently, the anticancer activity of BEA is a hot topic; however, there is no review article to discuss the anticancer activity of BEA. Therefore, in this review, we have mainly summarized the anticancer activity of BEA and thoroughly discussed its underlying mechanisms. In addition, the human exposure risk assessment of BEA is also discussed. We hope that this review will provide further information for understanding the anticancer mechanisms of BEA.


Assuntos
Depsipeptídeos/farmacologia , Depsipeptídeos/toxicidade , Exposição Ambiental/efeitos adversos , Fusarium/química , Micotoxinas/farmacologia , Micotoxinas/toxicidade , Antineoplásicos/farmacologia , Antineoplásicos/toxicidade , Humanos , Medição de Risco
11.
Environ Sci Pollut Res Int ; 23(2): 1158-72, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26507724

RESUMO

Air pollution is one of the most serious environmental problems in China due to its rapid economic development alongside a very large consumption of fossil fuel, particularly in the North China Plain (NCP). During the period 2011-2014, we integrated active and passive sampling methods to perform continuous measurements of NH3, HNO3, NO2, and PM2.5 at two urban, one suburban, and two rural sites in the NCP. The annual average concentrations of NH3, NO2, and HNO3 across the five sites were in the ranges 8.5-23.0, 22.2-50.5, and 5.5-9.7 µg m(-3), respectively, showing no significant spatial differences for NH3 and HNO3 but significantly higher NO2 concentration at the urban sites. At each site, annual average concentrations of NH3 and NO2 showed increasing and decreasing trends, respectively, while there was no obvious trend in annual HNO3 concentrations. Daily PM2.5 concentrations ranged from 11.8 to 621.0 µg m(-3) at the urban site, from 19.8 to 692.9 µg m(-3) at the suburban site, and from 23.9 to 754.5 µg m(-3) at the two rural sites, with more than 70% of sampling days exceeding 75 µg m(-3). Concentrations of water-soluble ions in PM2.5 ranked differently between the non-rural and rural sites. The three dominant ions were NH4(+), NO3(-), and SO4(2-) and mainly existed as (NH4)2SO4, NH4HSO4, and NH4NO3, and their concentrations averaged 48.6 ± 44.9, 41.2 ± 40.8, and 49.6 ± 35.9 µg m(-3) at the urban, suburban, and rural sites, respectively. Ion balance calculations indicated that PM2.5 was neutral at the non-rural sites but acidic at the rural sites. Seasonal variations of the gases and aerosols exhibited different patterns, depending on source emission strength and meteorological conditions. Our results suggest that a feasible pathway to control PM2.5 pollution in the NCP should target ammonia and acid gases together.


Assuntos
Poluentes Atmosféricos/análise , Amônia/análise , Material Particulado/análise , Aerossóis/análise , Poluição do Ar/análise , China , Monitoramento Ambiental , Gases/análise , Estações do Ano
12.
Arch Toxicol ; 88(11): 1915-28, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25199684

RESUMO

Deoxynivalenol (DON) is a group B trichothecene and a common contaminant of crops worldwide. This toxin is known to cause a spectrum of diseases in animals and humans such as vomiting and gastroenteritis. Importantly, DON could inhibit the synthesis of protein and nucleonic acid and induce cell apoptosis in eukaryote cells. The transduction of signaling pathways is involved in the underlying mechanism of the cytotoxicity of DON. Mitogen-activated protein kinase and Janus kinase/signal transducer and activator of transcription seem to be two important signaling pathways and induce the inflammatory response by modulating the binding activates of specific transcription factors. This review mainly discussed the toxic mechanism of DON from the vantage point of signaling pathways and also assessed the profiles of DON and its metabolites in humans. Importantly, we conducted a human exposure risk assessment of DON from cereals, cereal-based foods, vegetables, water, and animal-derived foods in different countries. Some regular patterns of DON occurrence in these countries are suggested based on an analysis of global contamination with DON. This review should provide further insight for the toxic mechanism study of DON and human exposure risk assessment, thereby facilitating mycotoxin control strategies.


Assuntos
Exposição Ambiental/efeitos adversos , Contaminação de Alimentos/análise , Tricotecenos/toxicidade , Animais , Monitoramento Ambiental , Humanos , Medição de Risco/métodos , Transdução de Sinais/efeitos dos fármacos
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