Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 26
Filtrar
1.
J Sep Sci ; 46(14): e2300112, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37132076

RESUMO

In this work, amphiphilic polymers synthesized from carboxylated carbon nanotubes stabilized high internal phase emulsions are demonstrated to be capable of direct extracting zearalenone and zearalanone in samples consisting of an oil-water emulsion system. Under optimal conditions, the maximum adsorption capacities for zearalenone and zearalanone are 17.27 and 13.26 mg/g. The adsorption is mainly attributed to π-π interaction, hydrophobic interaction, and hydrogen-bonding interaction for zearalenone and zearalanone. The adsorption isotherms reveal that the adsorption of zearalenone and zearalanone on amphiphilic polymers synthesized from carboxylated carbon nanotubes stabilized high internal phase emulsions follows Freundlich model with multilayer and heterogeneous adsorption due to the presence of multiple kinds of adsorption sites. The relative recoveries of the spiked zearalenone and zearalanone in corn juice samples range from 85% to 93% with relative standard deviations lower than 3.52%. The results manifest the high efficiency of amphiphilic polymers synthesized from carboxylated carbon nanotubes stabilized high internal phase emulsions for the adsorption and separation of analytes in the oil-water emulsion system. This study provides a new perspective on adsorbent engineering for the adsorption application in heterogeneous media.


Assuntos
Nanotubos de Carbono , Zearalenona , Zearalenona/análise , Nanotubos de Carbono/química , Zea mays , Emulsões , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida , Extração em Fase Sólida/métodos , Água
2.
Int J Mol Sci ; 24(9)2023 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-37175447

RESUMO

The adhesion G-protein-coupled receptor is a seven-transmembrane receptor protein with a complex structure. Impaired GPR56 has been found to cause developmental damage to the human brain, resulting in intellectual disability and motor dysfunction. To date, studies on gpr56 deficiency in zebrafish have been limited to the nervous system, and there have been no reports of its systemic effects on juvenile fish at developmental stages. In order to explore the function of gpr56 in zebrafish, the CRISPR/Cas9 gene-editing system was used to construct a gpr56-knockout zebrafish. Subsequently, the differentially expressed genes (DEGs) at the transcriptional level between the 3 days post fertilization (dpf) homozygotes of the gpr56 mutation and the wildtype zebrafish were analyzed via RNA-seq. The results of the clustering analysis, quantitative PCR (qPCR), and in situ hybridization demonstrated that the expression of innate immunity-related genes in the mutant was disordered, and multiple genes encoding digestive enzymes of the pancreatic exocrine glands were significantly downregulated in the mutant. Motor ability tests demonstrated that the gpr56-/- zebrafish were more active, and this change was more pronounced in the presence of cold and additional stimuli. In conclusion, our results revealed the effect of gpr56 deletion on the gene expression of juvenile zebrafish and found that the gpr56 mutant was extremely active, providing an important clue for studying the mechanism of gpr56 in the development of juvenile zebrafish.


Assuntos
Transcriptoma , Peixe-Zebra , Animais , Humanos , Mutação , Receptores Acoplados a Proteínas G/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo
3.
J Sep Sci ; 42(3): 716-724, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30548208

RESUMO

A facile and efficient strategy is developed to modify aptamers on the surface of the magnetic metal-organic framework MIL-101 for the rapid magnetic solid-phase extraction of ochratoxin A. To the best of our knowledge, this is the first attempt to create a robust aptamer-modified magnetic MIL-101 with covalent bonding for the magnetic separation and enrichment of ochratoxin A. The saturated adsorption of ochratoxin A by aptamer-modified magnetic MIL-101 was 7.9 times greater than that by magnetic metal-organic framework MIL-101 due to the former's high selective recognition as well as good stability. It could be used for extraction more than 12 times with no significant changes in the extraction efficiency. An aptamer-modified magnetic MIL-101-based method of magnetic solid-phase extraction combined with ultra high performance liquid chromatography with tandem mass spectrometry was developed for the determination of trace ochratoxin A with limit of detection of 0.067 ng/L. Ochratoxin A of 4.53-13.7 ng/kg was determined in corn and peanut samples. The recoveries were in the range 82.8-108% with a relative standard deviation (n = 5) of 4.5-6.5%. These results show that aptamer-modified magnetic MIL-101 exhibits selective and effective enrichment performance and have excellent potential for the analysis of ultra-trace targets from complex matrices.


Assuntos
Aptâmeros de Nucleotídeos/química , Contaminação de Alimentos/análise , Estruturas Metalorgânicas/química , Ocratoxinas/análise , Arachis/química , Fenômenos Magnéticos , Estruturas Metalorgânicas/síntese química , Zea mays/química
4.
Yao Xue Xue Bao ; 49(12): 1665-73, 2014 Dec.
Artigo em Zh | MEDLINE | ID: mdl-25920195

RESUMO

In order to enhance the specificity of TNF-α monoclonal antibody to inflamed site, a bispecific antibody BsDb that targets TNF-α and the extra-domain B (ED-B) of fibronectin (FN) was constructed by covalently linking the anti-TNF-α single chain Fv antibody (TNF-scFv) and the anti-ED-B scFv L19 via a flexible peptide linker deriving from human serum albumin (HSA). ED-B is an antigen specifically expressed at the inflamed site. BsDb is expressed in E. coli, identified by immunoblot, and purified with affinity chromatography. This was followed by further examination of its bioactivities and pharmacokinetics. We demonstrated that BsDb retained the immunoreactivity of its original antibodies as it could simultaneously bind to TNF-α and ED-B and neutralize the biological action of TNF-α. In the collagen-induced arthritis mice model, BsDb selectively accumulate in the inflamed joint with a maximal uptake of (12.2 ± 1.50)% ID/g in a single inflamed paw and retain in the inflamed paw for at least 72 h. In contrast, BsDb showed a short serum half-life of (0.50 ± 0.05) h and a rapid clearance from normal tissues. The findings reported herein indicate that BsDb has good specificity to the inflamed site and low toxicity to normal tissues. BsDb is therefore likely to have greater clinical applications in the treatment of rheumatoid arthritis and other autoimmune diseases. This laid a stable basis for its preclinical study.


Assuntos
Anticorpos Biespecíficos/química , Fibronectinas/química , Fator de Necrose Tumoral alfa/química , Animais , Anticorpos Monoclonais/química , Artrite Experimental , Escherichia coli , Meia-Vida , Humanos , Camundongos , Anticorpos de Cadeia Única/química
5.
J Chromatogr A ; 1720: 464794, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38484640

RESUMO

The distinctive morphology of dendritic mesoporous silica nanoparticles (DMSN) has recently attracted considerable attention in scientific community. However, synthesis of DMSN with well-defined structure and uniform size for ultrafast extraction of trace herbicide residues from environmental and food samples remains to be a compelling challenge. In this study, sulfhydryl functionalized dendritic mesoporous silica (SH-DMSN) was synthesized and the SH-DMSN showcases monodisperse microspheres with flower shape and precisely tailored and controllable pore sizes. This distinctive structural configuration accelerates mass transfer within the silica layer, resulting in heightened adsorption efficiencies. Furthermore, the particle sizes (455, 765, and 808) of the adsorbent can be meticulously fine-tuned by introducing distinct templates. Specifically, when the particle size is 765 nm, the optimized SH-DMSN exhibits a substantial specific surface area (691.32 m²/g), outstanding adsorption efficiencies (>90 %), remarkably swift adsorption and desorption kinetics (2 min and 3 min, respectively), and exceptional stability. The superior adsorption capabilities of this novel adsorbent, ranging from 481.65 to 1021.7 µg/g for organochlorine herbicides containing amide groups, can be attributed to the interplay of S-π interactions, halogen bonding, and electrostatic attraction interaction. These interactions involve the lone pair electrons of sulfhydryl and silanol groups with the π-electrons, halogen atoms and amide groups in herbicide molecules. This study not only offers a new perspective on advancing the practical utilization of dendritic mesoporous silica but also provides a pragmatic strategy for the separation and analysis of herbicides in diverse sample matrices.


Assuntos
Herbicidas , Nanosferas , Nanosferas/química , Dióxido de Silício/química , Halogênios , Porosidade
6.
Metabolism ; 157: 155953, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38885833

RESUMO

With aging and the increasing incidence of obesity, nonalcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease worldwide. NAFLD mainly includes simple hepatic steatosis, nonalcoholic steatohepatitis (NASH), liver fibrosis and hepatocellular carcinoma (HCC). An imbalance in hepatic iron homeostasis is usually associated with the progression of NAFLD and induces iron overload, reactive oxygen species (ROS) production, and lipid peroxide accumulation, which leads to ferroptosis. Ferroptosis is a unique type of programmed cell death (PCD) that is characterized by iron dependence, ROS production and lipid peroxidation. The ferroptosis inhibition systems involved in NAFLD include the solute carrier family 7 member 11 (SLC7A11)/glutathione (GSH)/glutathione peroxidase 4 (GPX4) and ferroptosis suppressor protein 1 (FSP1)/coenzyme Q10 (CoQ10)/nicotinamide adenine dinucleotide phosphate (NADPH) regulatory axes. The main promotion system involved is the acyl-CoA synthetase long-chain family (ACSL4)/arachidonic lipoxygenase 15 (ALOX15) axis. In recent years, an increasing number of studies have focused on the multiple roles of iron homeostasis imbalance and ferroptosis in the progression of NAFLD. This review highlights the latest studies about iron homeostasis imbalance- and ferroptosis-associated NAFLD, mainly including the physiology and pathophysiology of hepatic iron metabolism, hepatic iron homeostasis imbalance during the development of NAFLD, and key regulatory molecules and roles of hepatic ferroptosis in NAFLD. This review aims to provide innovative therapeutic strategies for NAFLD.


Assuntos
Ferroptose , Homeostase , Ferro , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Homeostase/fisiologia , Ferro/metabolismo , Ferroptose/fisiologia , Animais
7.
Heliyon ; 9(1): e12924, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36704287

RESUMO

At present, the global tunnel construction industry is developing rapidly, but construction accidents are also common. A large number of casualties and property losses are alarming people. It is urgent to pay attention to the causes of tunnel construction accidents, ensure the safety of construction sites, and reduce tunnel construction accidents. Through literature and case analysis, we have sorted out 35 typical tunnel causative factors for research and analysis, which are divided into 7 types. Based on the variable system, we prepared a measurement questionnaire, and 536 valid questionnaires were collected. The structural equation model (SEM) was used to study the relationship between these variables. The influence mechanism and interaction relationship between the variables are analyzed in depth in terms of influence intensity and path coefficient. The results showed that the following six latent variables significantly influence tunnel construction accidents: human factors, material factors, geological exploration design, technical management, safety management, and natural conditions. Natural conditions have the most significant impact, followed by human factors and safety management. Particular attention should be paid to education, training, and safety management in construction risk control. The structural model and research results are helpful to establish the cause theory of tunnel construction accidents, and guide the formulation of safety management policies for tunnel construction projects, reduce tunnel accidents and ensure construction safety.

8.
Accid Anal Prev ; 192: 107230, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37556999

RESUMO

The continuous growth of automobile ownership and road mileage in China has brought a lot of road maintenance work. The work zone shall be set for road maintenance work. Due to the road characteristics near the work zone, more accidents and a higher accident risk exist. Traffic signs are one of the essential means to ensure traffic safety. The location and number of road work signs (sign level) play a crucial role in driver safety near the work zone. The repeated road work signs can form a warning system to regulate driver behavior. This paper evaluates the effect of the number of warning signs with and without distance information on driver behavior (psychological load and physiological characteristics) near the work zone. The matter-element extension model is used for comprehensive evaluation. The study resulted in several findings. First, adding distance information improves the difficulty and time of visual recognition and enhances driver alertness. On the other hand, too many road signs are not conducive to maintaining driver alertness. Second, distance information on the work signs and the repeated setting of road warning signs add extra burden on the driver and increase driver fatigue. Third, driver's response to the repeated road work signs will gradually become stable; The speed transition under the warning signs Levels 2 and 3 are more stable than that under the warning sign Levels 1 and 4. Finally, the warning sign level shall not be more than 3. If the advanced warning area is short, it is recommended to select a warning sign Level 1. If the advanced warning area is relatively long, it is recommended to choose a warning sign Level 2. Finally, adding distance information will improve the overall effect of the warning scheme. These findings can provide a valuable reference for setting the road work signs near the work zone in practice in China.


Assuntos
Acidentes de Trânsito , Condução de Veículo , Humanos , Adulto Jovem , Acidentes de Trânsito/prevenção & controle , Condução de Veículo/psicologia , Segurança , Atenção , China
9.
Environ Sci Pollut Res Int ; 30(23): 64154-64167, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37060407

RESUMO

Based on the accident causation theory, the mechanism and inducement of construction safety risk in mining enterprises are clarified. The safety risk system of mining enterprises is divided into five subsystems: personnel, material equipment, technology, environment, and management by rough set theory. The comprehensive weight of each risk factor is calculated by network analytic hierarchy process and fuzzy comprehensive evaluation method. Taking a mine in Shanxi Province as the research object, the causal traceability diagram and stock flow diagram of the risk system of mining enterprises are constructed by means of system dynamics model. The influence of various risk factors of the mine on the overall safety risk management level of the enterprise is simulated, and the numerical value of key personnel influence factors is adjusted. The sensitivity changes of safety productivity and safety risk management level of mining enterprises in different situations are analyzed. The results show that: (1) the management and personnel subsystem has the greatest impact on the safety risk management of mining enterprises, followed by the technology, material equipment, and environment subsystem. (2) Increasing safety input can improve the safety level and reduce the expected safety value time, otherwise it will reduce the safety level and delay the expected safety value time. (3) Further simulation of the personnel subsystem, it is found that the factors affecting the safety level of mining enterprises contain six factors, namely, the technical level of construction personnel, the management level of manager, the conduct code of construction personnel, the safety consciousness of practitioners, the basic quality of construction personnel, and the physical and mental state of construction personnel. (4) The conversion rate of personnel safety input to manager's management level and the safety consciousness of practitioners presents a steep decline-slow rise-gradually steady development trend, which mainly because the benefits of safety input have certain time delay and lag.


Assuntos
Minas de Carvão , Mineração , Gestão da Segurança , Gestão de Riscos , Acidentes , Carvão Mineral , Minas de Carvão/métodos
10.
Sci Rep ; 13(1): 18886, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37919385

RESUMO

Owing to issues such as time and cost, patients often show poor acceptance of and adherence to center-based cardiac rehabilitation (CBCR), which impacts the effectiveness of rehabilitation. Therefore, there is growing interest in home-based cardiac rehabilitation and cardiac telerehabilitation (CTR), which entail less time and cost than CBCR. This study aimed to compare the changes in physiological and psychological indicators, compliance, and satisfaction after CTR and CBCR. In this single-blind, randomized, controlled trial, the intervention group received CTR via the 5G Internet of Things platform, while the control group received CBCR. Data from 50 patients (age 66.28 ± 4.01 years) with acute myocardial infarction who underwent percutaneous coronary intervention were analyzed. After an intervention period of three months, the maximal oxygen uptake and metabolic equivalent of task were 5.53 ± 0.12 and 19.32 ± 0.17, respectively, in the intervention group, and 4.15 ± 0.13 and 16.52 ± 0.18, respectively, in the control group. After three months of intervention, there were significant differences between the two groups in all observed indicators (p < 0.05), except for low-density lipoprotein and the incidence of major adverse cardiovascular events (p > 0.05). The use of a 5G Internet of Things platform cardiac rehabilitation model effectively improved outcomes in patients with acute myocardial infarction who underwent percutaneous coronary intervention. Trials registry: The study protocol was registered at Chinese Clinical Trials Registry (ChiCTR), first trial registration 07/08/2023, identification number ChiCTR2300074435.


Assuntos
Internet das Coisas , Infarto do Miocárdio , Telerreabilitação , Humanos , Pessoa de Meia-Idade , Idoso , Telerreabilitação/métodos , Projetos Piloto , Método Simples-Cego , Internet , Infarto do Miocárdio/cirurgia
11.
Yao Xue Xue Bao ; 47(9): 1210-8, 2012 Sep.
Artigo em Zh | MEDLINE | ID: mdl-23227553

RESUMO

In order to increase the plasma half-life and tissue specificity of IL-1 receptor antagonist, a recombinant fusion protein IL-1Ra-HSA, linked by a rigid peptide linker PAPAP, was engineered and expressed by the Pichia pastoris host cells. The fusion protein was secreted to the host cells culture, identified by Western blot, and purified by affinity chromatography. This was followed by a further examination of its bioactivity and pharmacokinetics. Our results demonstrated that the fusion protein retained the antagonist activity of IL-1Ra, capable of binding specifically to the IL-1 receptor on human melanoma A375.S2 cells, and inhibits the cytolytic effect of IL-1beta to A375.S2 cells. Albumin fusion dramatically extended the half-life of IL-1Ra and resulted in a specific accumulation of IL-1Ra in the arthritic paws and a lower distribution of IL-1Ra in other organs such as liver, kidney, spleen and lung in mice with collagen-induced arthritis. The findings reported herein indicate that the fusion protein is likely to have greater clinical applications in areas such as the treatment of rheumatoid arthritis.


Assuntos
Apoptose/efeitos dos fármacos , Artrite Experimental/metabolismo , Proteína Antagonista do Receptor de Interleucina 1 , Albumina Sérica , Animais , Linhagem Celular Tumoral , Membro Anterior/metabolismo , Meia-Vida , Humanos , Proteína Antagonista do Receptor de Interleucina 1/genética , Proteína Antagonista do Receptor de Interleucina 1/metabolismo , Proteína Antagonista do Receptor de Interleucina 1/farmacocinética , Proteína Antagonista do Receptor de Interleucina 1/farmacologia , Interleucina-1beta/toxicidade , Masculino , Melanoma/patologia , Camundongos , Camundongos Endogâmicos DBA , Pichia/genética , Pichia/metabolismo , Plasmídeos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/farmacocinética , Proteínas Recombinantes de Fusão/farmacologia , Albumina Sérica/genética , Albumina Sérica/metabolismo , Albumina Sérica/farmacocinética , Albumina Sérica/farmacologia , Distribuição Tecidual
12.
Artigo em Inglês | MEDLINE | ID: mdl-35627442

RESUMO

Based on the theory of rational action (TRA), overconfidence theory (OT), and deterrence theory (DT), this study explores the reasons for mobile phone use by Chinese students riding electronic bicycles (e-bikes) in Fuzhou City. We tested the reliability and validity of an extended TPB, OT and DT questionnaire (with 531 eligible responses) and constructed a structural equation model of mobile phone use behavior while riding e-bikes, based on the improved model. The structural equation model (SEM) is used to evaluate the relationship between the internal factors of mobile phone riding behavior. The results show that the correlation among mobile phone dependence, punishment mechanism, attitude, and controllable operation impacts e-bike riders' behavior when using mobile phones while riding.


Assuntos
Telefone Celular , Motocicletas , Ciclismo , Humanos , Reprodutibilidade dos Testes , Assunção de Riscos
13.
Heliyon ; 8(6): e09561, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35669541

RESUMO

This paper presents a study of the causes of anger of students who ride electric bicycles on a university campus. A questionnaire survey of 370 students in university was conducted using a electric bicycle rider anger scale. Structural equation model is used to analyze the interaction between pedestrians, traffic management, other riders and environment and riders themselves. The results show that the overall level of students' riding anger on the campus was not high, and the interaction with the surrounding environment mainly reflected the riding anger of college students. The interaction of students' anger with campus traffic management requirements was relatively low. Based on the study results, several campus traffic management and safety education recommendations are made.

14.
Artigo em Inglês | MEDLINE | ID: mdl-36554557

RESUMO

Despite the continuous progress of tunnel construction technology and safety management technology, road tunnel construction safety still faces many challenges in China, such as how to ensure the effective management and safety control of people and materials, how to ensure the implementation of technology and program implementation, risk assessment of construction site environmental information, etc. Exploring the causes of tunnel construction accidents and understanding the properties of the factors and their interrelationships can effectively control the sources of risk and contribute to the safety control of tunnel construction. Therefore, we have collected 30 formal accident investigation reports from the government safety supervision and management department from 2005 to 2021, including detailed investigation and accident analysis. Based on grounded theory, a qualitative research method to generalize experience through direct observation, abstraction, and analysis of data, we use Nvivo11 software to analyze reports and obtain 6 selective codes, 16 spindle codes, and 43 open codes. In addition, we construct a theoretical model of tunnel construction accident influencing factors, which passed the saturation test. The Decision-Making Trial and Evaluation Laboratory (DEMATEL) model is used to analyze the influencing mechanism and interaction relationships of these factors. The two dimensions of influence degree and centrality are used to determine the critical influencing factors of tunnel construction accidents in mountainous areas. They are security awareness and professionalism. According to the cause degree, the influencing factors are divided into cause and result factors. Finally, the basis and suggestions for reducing construction accidents are presented.


Assuntos
Acidentes , Indústria da Construção , Humanos , Teoria Fundamentada , China , Gestão da Segurança/métodos , Medição de Risco/métodos
15.
Mar Pollut Bull ; 185(Pt B): 114320, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36410194

RESUMO

Considering the interrelatedness of river and bay ecosystems, river and bay water quality management is shifting to integrated management across coastlines. Here, an integrated management indicator for the coordinated and efficient nitrogen abatement of the Bohai Sea and its basin was proposed. The terrigenous total nitrogen (TN) allocated load was optimized under the dual water quality constraints for both river and bay using a simulation-optimization method. The contributing jurisdictions were identified by their TN overload rates, and their responsibility apportionment rate for specific nitrogen-polluted segment was quantified. Integrated TN reduction scheme resulted in a 29 % greater reduction in bay and river nitrogen pollution than the equal proportion reduction approach. In 18 % of the watersheds in the Bohai basin, the water quality standards of the river were more restrictive than the standards of the bay. Integrated management scheme has higher coordination of river and sea management objectives.


Assuntos
Rios , Qualidade da Água , Ecossistema , Nitrogênio , China
16.
Anal Chim Acta ; 1227: 340270, 2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36089309

RESUMO

In this work, a porous capillary monolithic column was simply prepared by in situ thiol-alkyne click polymerization of dipentaerythritol hexakis (3-mercaptopropionate) and dimethyl dipropargylmalonate in fused-silica capillary. The capillary monolithic column shows excellent permeability, high porosity, and thoiether-rich groups, thereby, a high-efficient capacity for trace estrogens from complex samples are obtained via electron-donor-acceptor π-π interaction and hydrophobic interaction. The highest adsorption efficiency for estrogens is achieved at pH = 7.0 with a flow rate of 0.200 mL min-1. The superior adsorption capacities of the as-prepared capillary column for eight estrogens range from 0.092 mg m-1 to 0.31 mg m-1. A simple, reliable, and sensitive method for the determination of eight estrogens in biological and environmental samples is developed using the monolithic polymer as in-tube solid-phase microextraction coupled with ultrahigh performance liquid chromatography-tandem mass spectrometry (SPME-UPLC-MS/MS), and the total instrumental analysis time for the SPME-UPLC-MS/MS procedures was about 60 min per sample. The developed method shows a wide linear range (0.0500-5.00 µg L-1), and low limits of detection (5.34-9.63 ng L-1) for estrogens. The concentrations of estrogens in serum, urine, and pond water samples are found to be no more than 3.69, 0.741, and 1.04 µg L-1, respectively, and the satisfying recoveries for the eight estrogens range from 80.3% to 113% with relative standard deviations (n = 5) of 1.5-9.4%. The established method is highly potential for extraction and analysis of ultratrace target estrogens in complex matrices, such as biological and environmental samples.


Assuntos
Estrogênios , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Estrogênios/análise , Porosidade
17.
Zhong Yao Cai ; 34(5): 738-46, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21954562

RESUMO

OBJECTIVE: To set up a suitable IEC-6 migration model for pharmacological research and observe the effect of complex polysaccharide from Astragalus membranaceus (Fisch.) Bge. var. mongholicus (Bge.) Hsiao to IEC-6 cell migration. METHODS: The main conditions related to the establishment of the model, including the planting density of the cell, the observation time after scratching, the concentration of the auxiliary material Matrigel, the treatment of the serum-starvation, the concentration of alpha-difluoromethylornithine (DFMO), an inhibitor of the cell migration, were investigated respectively; and the effects of the tested medicines on the model were observed. RESULTS: 4 x 10(5) cell/mL was the suitable planting density of the cell in the 6-well plate; at the 24th hour after scratching was the appropriate time to count the migrating cells; and the proper concentration of Matrigel was 5%; the serum-starvation could evidently reduce the migrating cells, so the culture medium should contain the serum; 2.5 - 5 mmol/L DFMO was proper for inhibition of the cell migration. Complex polysaccharide from Astragalus membranaceus and spermidine both can promote cell migration. CONCLUSION: The established model of IEC-6 cell migration was suitable for intestinal epithelial restitution such as the researches on pathophysiological mechanisms is the effects of the medicines on the cell migration.


Assuntos
Movimento Celular , Células Epiteliais/efeitos dos fármacos , Intestinos/citologia , Modelos Biológicos , Polissacarídeos/farmacologia , Animais , Astragalus propinquus/química , Técnicas de Cultura de Células/métodos , Linhagem Celular , Ensaios de Migração Celular/métodos , Meios de Cultura/metabolismo , Eflornitina/metabolismo , Células Epiteliais/citologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Intestinos/fisiologia , Ratos , Espermidina/farmacologia , Cicatrização
18.
Front Psychol ; 12: 646406, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34671283

RESUMO

In recent years, the mileage of the tunnels has substantially increased with the rapid highway construction that led to increasing highway tunnels. Most studies on tunnel accidents have mainly focused on the external environments, such as tunnel structure, traffic volume, and lighting. In addition, although many studies on mental load of drivers have been conducted for public roads, such studies for highway tunnels have been limited. In this study, three scenarios with different front vehicle speeds (60, 45, and 30 km/h) in a two-lane long tunnel (one lane in each travel direction) were evaluated using a driving simulator. The experiment involved 24 participants (14 men and 10 women) with an average age of 25.8 years and an average experience of 3.2 years. The electroencephalogram (EEG) technology was used to collect the leading EEG indicators during the driving simulation of the scenarios: α, ß, and θ waves and the wave ratio, (α + θ)/ß. According to the ß-wave energy measurements, the alertness of drivers was the lowest at 45 km/h after adapting to the tunnel environment, indicating that the drivers were more comfortable at this speed. This preliminary finding should help in determining the speed limit in this type of tunnel.

19.
Front Psychol ; 12: 693005, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34248797

RESUMO

Driving behavior in a highway tunnel could be affected by external environmental factors like light, traffic flow, and acoustic environments, significantly when these factors suddenly change at the moment before and after entering a tunnel. It will cause tremendous physiological pressure on drivers because of the reduction of information and the narrow environment. The risks in driving behavior will increase, making drivers more vulnerable than driving on the regular highways. This research focuses on the usually neglected acoustic environment and its effect on drivers' physiological state and driving behavior. Based on the SIMLAB driving simulation platform of a highway tunnel, 45 drivers participated in the experiment. Five different sound scenarios were tested: original highway tunnel sound and a mix of it with four other sounds (slow music, fast music, voice prompt, and siren, respectively). The subjects' physiological state and driving behavior data were collected through heart rate variability (HRV) and electroencephalography (EEG). Also, vehicle operational data, including vehicle speed, steering wheel angle, brake pedal depth, and accelerator pedal depth, were collected. The results indicated that different sound scenarios in the highway tunnel showed significant differences in vehicle speed (p = 0.000, η2 = 0.167) and steering wheel angle (p = 0.007, η2 = 0.126). At the same time, they had no significant difference in HRV and EEG indicators. According to the results, slow music was the best kind of sound related to driving comfort, while the siren sound produced the strongest driver reaction in terms of mental alertness and stress level. The voice-prompt sound most likely caused driver fatigue and overload, but it was the most effective sound affecting safety. The subjective opinion of the drivers indicated that the best sound scenario for the overall experience was slow music (63%), followed by fast music (21%), original highway tunnel sound environment (13%), and voice-prompt sound (3%). The findings of this study will be valuable in improving acoustic environment quality and driving safety in highway tunnels.

20.
Accid Anal Prev ; 146: 105705, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32818759

RESUMO

The rapid development of expressways has led to an increasing number of place names that must be displayed on road guide signs. As a result, multi-board guide signs have been increasingly set up on expressways. The main aim of this study was to analyze the effect of the directional road sign displayed on multi and single-board signs on driver mental workload and behavior. 32 participants including 16 females (mean age = 24.7 years, standard deviation = 1.9 years) participated in the experiment and completed 3 driving simulation scenes. The setting of each scene-sign board was different: 1 board, 2 boards, and 3 boards. The driver needed to reach the designated destination according to the guidance of the road signs. Eye tracker was used to measure the fixation, saccade and electroencephalogram (EEG) was used to measure the alpha (8-13 hz) band absolute power in different signage scenarios. There are two major findings of the study. First, when the number of place names is less than or equal to 7, the multi-board sign generates more mental workload than the single-board sign does. The alpha band power of the driver's frontal area under the multiple boards is lower and affects driving performance (the deceleration is greater). Second, when the number of place names is more than 7, there is no significant difference in the effect on mental workload whether multi or single-board sign is used. However, compared to the single-board sign, drivers in the case of multi-board sign are likely to reduce the fixation duration and increase the number of saccades. The results suggest that it is not necessary to use multi-board signs when the number of place names is less than 7. These findings provide more safety considerations for the setting of multi-board guide signs in the future.


Assuntos
Acidentes de Trânsito , Atenção , Condução de Veículo/psicologia , Planejamento Ambiental , Processos Mentais , Acidentes de Trânsito/prevenção & controle , Adulto , Ondas Encefálicas , Comunicação , Simulação por Computador , Eletroencefalografia , Movimentos Oculares , Feminino , Humanos , Masculino , Carga de Trabalho , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA