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1.
Sci Rep ; 14(1): 7685, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561405

RESUMO

The colloidal borescope, using colloidal particle motion, is used to monitor the flow velocities and directions of groundwater. It integrates advanced techniques such as microscopy, high-speed photography, and big data computing and enjoys high sensitivity at the micron level. However, In the same well, the groundwater flow velocity monitored by colloidal hole mirror is varies greatly from that obtained by conventional hydrogeological monitoring, such as pumping test. In order to solve this problem, the stability catcher and stratified packer are designed to control the interference of the vertical flow in drilling, and to monitor the flow velocity and direction of groundwater velocity at the target aquifer and target fracture. Five wells with different aquifers and different groundwater types were selected for monitoring in south-central China. The instantaneous velocity and direction are converted into east-west component and north-south component, the average velocity and direction is calculated according to the time of 10 min, and the particle trajectory diagram is established. Based on these results, it proposed a concept of cumulative flow velocity. Using curve-fitting equations, the limits of cumulative flow velocities as the monitoring time tends to infinity were then calculated as the actual flow velocities of the groundwater. The permeability coefficient of aquifer is calculated by using the fissure ratio of aquifer, hydraulic slope and flow velocity, and compared with the permeability coefficient obtained by pumping test. The results are as follows: (1) The variation coefficient of the instantaneous flow velocity measured at the same depth in the same well at different times is greater than that of the time average flow velocity and greater than that of the cumulative flow velocity. The variation coefficient of the actual velocity is the smallest, indicating that the risk of using the actual flow velocity is lower. (2) The variation coefficient of the flow rate monitored at different depths in the same well is mainly controlled by the properties of the aquifer. The more uniform water storage space in the aquifer, the smaller the variation coefficient. (3) The comparison between the permeability coefficient obtained by monitoring and the permeability coefficient obtained by pumping test shows that the flow of structural fissure water controlled by planar fissure is more surface flow, and the results are consistent. When the groundwater flow is controlled by pores and solution gaps, the flow channel is complicated, which is easy to produce turbulent flow, and the result consistency is poor. (4) According to different research accuracy requirements, different monitoring and calculation methods can be selected for different aquifers and groundwater types. Researches show that, the permeability coefficient calculated for the actual flow velocity in well DR01 is the same as that calculated for the pumping test. The aquifer characteristics reflected by the coefficient of variation of the actual flow velocity in the same aquifer are more realistic. The pumping test method obtains the comprehensive parameters of a certain aquifer, and this method can be used to monitor a certain fissure. In this paper, the new technology developed for monitoring, and the new algorithm established for data processing, can accurately obtain the flow velocity and direction of groundwater, using capsule hole mirror monitoring method. The key parameters of hydrogeology can be obtained by using one well, which can reduce the time and cost input and improve the work efficiency.

2.
Sci Total Environ ; 923: 171411, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38442761

RESUMO

Plastic advertising banners (PABs) have been widely used for advertising and publicizing with large usage amount. The PABs are usually added with plenty of chemical additives for improving material performance, and the additives can be released during the lifetime of the PABs. However, limited knowledge is available on the composition and release of the additives in the PABs. In this study, benzenoids were found as the dominant additive categories in PABs. Release kinetics of benzenoid additives with high detection frequency and high abundance from the PABs under indoor and outdoor environments were investigated. During the 150-day release experiment, average release rates of the additives from the PABs under outdoor and indoor environments were 8.3 × 10-10 kg/m2·s and 6.3 × 10-10 kg/m2·s, respectively. The release rates of the additives were negatively related to the thickness of the PAB samples. Health risk assessment indicated that chemicals associated with PABs have potential carcinogenic risks to salesmen in the shopping malls. The risks of chemical exposure associated with PABs to consumers in the shopping malls were acceptable. This study unveils a considerable source of chemical exposure to humans.


Assuntos
Publicidade , Plásticos , Humanos , Medição de Risco
4.
Dalton Trans ; 53(6): 2626-2634, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38224010

RESUMO

A supercapacitor (SC) is considered as a promising energy storage device because of its high power density, fast charging/discharging speed and long cycle life. The transition metal oxides prepared by traditional methods face some challenges, such as low conductivity and uncontrollable pore size distribution. Therefore, we have prepared Prussian blue analogues (PBAs) using a coprecipitation method. By adjusting additives in the experimental process, uniform PBAs with a series of regular morphologies and structures are successfully prepared. Then the corresponding metal oxides are obtained by calcining precursors. We systematically study the influence of the morphology and structure of metal oxides Co3O4/Fe2O3 derived from PBAs on their electrochemical performance. The metal oxide with a partially hollow and octahedral structure shows excellent electrochemical performance. In a neutral electrolyte, the specific capacitance is 659.7 F g-1 at a current density of 0.5 A g-1. After 6000 cycles, the capacitance retention rate is 63.7%. An asymmetric supercapacitor (ASC) is constructed using Co3O4/Fe2O3 with an octahedral structure (CFMO-PVP-2) as the positive electrode and YP-50F as the negative electrode. The maximum energy density is 31.4 W h kg-1 at a power density of 1921 W kg-1. The maximum power density is 8421 W kg-1 at an energy density of 23.5 W h kg-1. The excellent electrochemical performance is attributed to the low resistance (Rw and Rct) and high DOH- derived from the oxide particles on the surface and within the inner parts of the octahedron, which are available for electron transport. Meanwhile, the open void between adjacent nanoparticles allows the electrolyte ions to diffuse more efficiently and ensures a much more effective area for participating in a reaction. The strategy will give new insights into designing high-performance SCs based on PBAs.

5.
Environ Pollut ; 344: 123312, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38199480

RESUMO

Unveiling composition and release rates of chemicals in chemical-intensive products (CIPs) such as inkjet fabrics that are applied extensively in advertising and publicizing industries, is of importance to sound management of chemicals. This study tentatively identified 212 compounds from 69 inkjet fabric samples using gas chromatograph coupled with quadrupole time-of-flight mass spectrometry (GC-QTOF-MS). Contents of six phthalate esters (PAEs) were quantified to range from 3.0 × 102 mg/kg to 3.1 × 105 mg/kg with GC-MS. Bis(2-ethylhexyl) phthalate was predominantly detected to average 96 g/kg. The inkjet fabrics collected from southern China contained fewer non-intentionally added substances (NIASs) than from northern China. Annual mass release rates (RM) of the 6 PAEs from inkjet fabrics to air were estimated to range from 1.4 × 10-2 kg/year to 2.8 × 104 kg/year in China in 2020, and the mean indoor RM was comparable with the outdoor one. Equilibrium partition coefficients of the compounds between the product and air, ambient temperature, and concentrations of chemicals in the product, are key factors leading to RM with the high variance. The findings indicate that contents of the NIASs in the CIPs should be minimized, and the refining concept should be adopted in design of the CIPs, so as to control the release of chemicals from the CIPs.


Assuntos
Ésteres , Ácidos Ftálicos , Ésteres/análise , Ácidos Ftálicos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , China
6.
J Environ Manage ; 351: 119820, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38113783

RESUMO

Heavy metals (HMs) pollution threatens food security and human health. While previous studies have evaluated source-oriented health risk assessments, a comprehensive integration of environmental capacity risk assessments with pollution source analysis to prioritize control factors for soil contamination is still lacking. Herein, we collected 837 surface soil samples from agricultural land in the Nansha District of China in 2019. We developed an improved integrated assessment model to analyze the pollution sources, health risks, and environmental capacities of As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn. The model graded pollution source impact on environmental capacity risk to prioritize control measures for soil HMs. All HMs except Pb exceeded background values and were sourced primarily from natural, transportation, and industrial activities (31.26%). Approximately 98.92% (children), 97.87% (adult females), and 97.41% (adult males) of carcinogenic values exceeded the acceptable threshold of 1E-6. HM pollution was classified as medium capacity (3.41 kg/hm2) with mild risk (PI = 0.52). Mixed sources of natural backgrounds, transportation, and industrial sources were identified as priority sources, and As a priority element. These findings will help prioritize control factors for soil HMs and direct resources to the most critical pollutants and sources of contamination, particularly when resources are limited.


Assuntos
Metais Pesados , Poluentes do Solo , Adulto , Criança , Humanos , Solo , Monitoramento Ambiental , Chumbo , Poluentes do Solo/análise , Medição de Risco , China , Metais Pesados/análise , Cádmio
7.
Ecotoxicol Environ Saf ; 267: 115642, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37924799

RESUMO

Heavy metals (HMs) in groundwater seriously threaten ecological safety and human health. To facilitate the effective management of groundwater contamination, priority control factors of HMs in groundwater need to be categorized. A total of 86 groundwater samples were collected from the Huangpi district of Wuhan city, China, during the dry and wet seasons. To determine priority control factors, a source-oriented health risk assessment model was applied to compare the pollution sources and health risks of seven HMs (Cu, Pb, Zn, Cr, Ni, As, and Fe). The results showed that the groundwater had higher As and Fe contents. The sources of HM pollution during the wet period were mainly industrial and agricultural activities and natural sources. During the dry period, origins were more complex due to the addition of domestic discharges, such as sewage wastewater. Industrial activities (74.10% during the wet period), agricultural activities (53.84% during the dry period), and As were identified as the priority control factors for groundwater HMs. The results provide valuable insights for policymakers to coordinate targeted management of HM pollution in groundwater and reduce the cost of HM pollution mitigation.


Assuntos
Água Subterrânea , Metais Pesados , Poluentes do Solo , Humanos , Monitoramento Ambiental , Medição de Risco , Poluição Ambiental/análise , Cidades , Metais Pesados/análise , China , Poluentes do Solo/análise
8.
Ear Nose Throat J ; : 1455613231181711, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37381663

RESUMO

Objective: This study aims to examine the clinical efficacy and prognostic factors associated with nerve growth factor (NGF) treatment for sudden sensorineural hearing loss (SSHL). Materials and methods: A retrospective analysis was conducted on the clinical data of 101 patients with moderate or more severe SSHL who underwent secondary treatment at Sun Yat-sen Memorial Hospital of Sun Yat-sen University between January 2019 and July 2020. Prior to treatment, all patients were assessed using Pure Tone Audiometry (PTA), auditory brainstem response, otoacoustic emission, temporal bone computed tomography, or inner ear magnetic resonance imaging. Fifty-seven patients received conventional systemic treatment and served as the control group, while 44 patients received NGF in conjunction with conventional systemic treatment, forming the experimental group. PTA results were compared between the two groups before treatment and at 1 week, 2 weeks, and 1 month post-treatment. Additionally, the impact of age, sex, affected side, hypertension, and other factors on patient prognosis was analyzed. Results: Both groups demonstrated significant PTA improvements following treatment, with a statistically significant difference (P < .05). The hearing recovery effective rate in the control group was 42.1%, while that of the experimental group reached 70.5%, with a statistically significant difference between the groups (P < .05). Most patients experienced notable hearing improvements 1 week after treatment, with some patients still showing progress 2 weeks post-treatment. Multifactor analysis revealed that hypertension and onset days were associated with treatment outcomes. Conclusion: Secondary treatment remains clinically significant for patients with SSHL who have not achieved a satisfactory response or show no clear improvement following initial treatment. The presence of hypertension and delayed treatment are negative factors related to treatment efficacy.

9.
Drug Des Devel Ther ; 17: 1741-1752, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37333962

RESUMO

Purpose: This study aimed to explore the effects of different injection rates of propofol on postoperative cognition in elderly patients undergoing laparoscopic inguinal hernia repair. Methods: A total of 180 elderly patients who planned to undergo laparoscopic inguinal hernia repair were randomly divided into three groups: slow injection of propofol (VS-Group, 30 mg kg-1 h-1); medium injection of propofol (VM-Group, 100 mg kg-1 h-1) or fast injection of propofol (VF-Group, 300 mg kg-1 h-1). Propofol was induced by microinfusion pump, and the depth of anesthesia was monitored by bispectral index (BIS). Propofol and remifentanil were continuously infused during anesthesia maintenance and adjusted according to BIS. The primary outcome was the use of the Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) to measure the incidence of postoperative cognitive decline (POCD) in elderly patients on the first and seventh postoperative day. Secondary outcomes included induced dose of propofol, incidence of burst suppression and maximum electroencephalographic (EEG) effect of propofol (BIS-min) during induction. Results: The incidence of POCD on the first and seventh day postoperatively was similar among the three groups (P > 0.05). However, with the increase of propofol injection rate, induced dose of propofol, incidence of burst suppression and BIS-min during induction, the number of patients requiring vasoactive agents were significantly increased (P < 0.001). Multivariate regression analysis showed that the brief duration of burst suppression during induction did not affect the occurrence of POCD, while age and duration of hospitalization were risk factors for POCD. Conclusion: For elderly patients undergoing laparoscopic inguinal hernia repair, lowering the injection rate of propofol (such as 30 mg kg-1 h-1) cannot decrease the incidence of early POCD, but reduces induction dose of propofol and use of vasoactive drugs, making the patient's hemodynamics more stable.


Assuntos
Delírio , Hérnia Inguinal , Laparoscopia , Propofol , Humanos , Idoso , Propofol/efeitos adversos , Anestésicos Intravenosos/efeitos adversos , Hérnia Inguinal/cirurgia , Hérnia Inguinal/induzido quimicamente , Complicações Pós-Operatórias/epidemiologia , Cognição
10.
Neuroscience ; 523: 80-90, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37257555

RESUMO

Epidemiological studies have demonstrated that women are less susceptible to Parkinson's disease (PD) than men. Estrogen exposure is hypothesized to confer protection against dopaminergic neuronal loss in patients with PD. Although the accumulation and propagation of α-synuclein (α-Syn) are closely linked to the clinical progression of PD, no relevant research has examined whether α-Syn proteostasis in the brain is altered in women after menopause. In this study, we established long-term ovariectomized (OVX) mice to simulate late post-menopause and investigated the expression and aggregation of α-Syn following the ovariectomy procedure. We observed that the OVX mice exhibited a significant increase in the expression and aggregation of α-Syn in the striatum and midbrain accompanied by impaired motor performance at 3 months after ovariectomy. The accumulation of α-Syn did not result in a significant loss of nigral dopaminergic neurons but did enhance autophagy and neuroglial activation. These findings imply that menopause may disrupt α-Syn proteostasis and exacerbate the accumulation of α-Syn in the basal ganglia circuit.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Animais , Feminino , Camundongos , alfa-Sinucleína/metabolismo , Encéfalo/metabolismo , Neurônios Dopaminérgicos/metabolismo , Mesencéfalo/metabolismo , Doença de Parkinson/metabolismo , Proteostase
11.
CNS Neurosci Ther ; 29(7): 1817-1829, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36852451

RESUMO

AIMS: Multiple guidance cues, such as netrin-1 (NTN-1)/deleted in colorectal carcinoma (DCC), control the guidance of axons and help establish functional neural circuits during development. However, the function of these guidance molecules during the neurodegenerative process is unclear. METHODS: To access the alterations of NTN-1 and DCC during the onset and progression of PD, we first established two subacute and one chronic PD model. Then, we investigated the relationship between the NTN-1/DCC pathway and cell death in SH-SY5Y cells. Finally, we conducted correlation studies between plasma NTN-1 and parkinsonian symptoms in patients to understand how this pathway contributes to PD. RESULTS: We found that the imbalance of NTN-1 and DCC was a common feature of nigral DA neuron injury in PD mouse models. We investigated that MPP+ inhibited NTN-1 expression and increased DCC expression in a concentration- and time-dependent manner. We further discovered a significant decrease in plasma NTN-1 levels and a positive correlation with UPDRS scores in PD patients. CONCLUSION: Our findings confirmed the imbalance of NTN-1/DCC signaling during nigral degeneration in experimental PD models and found for the first time a correlation of plasma NTN-1 with PD symptoms in patients.


Assuntos
Neuroblastoma , Doença de Parkinson , Camundongos , Animais , Humanos , Fatores de Crescimento Neural/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Netrina-1 , Células Cultivadas , Axônios/metabolismo , Receptor DCC
12.
Sci Rep ; 12(1): 22335, 2022 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-36572795

RESUMO

Radix Bupleuri (Chaihu in Chinese) is a traditional Chinese medicine commonly used to treat colds and fevers. The root metabolome and transcriptome of two cultivars of B. chinense (BCYC and BCZC) and one of B. scorzonerifolium (BSHC) were determined and analyzed. Compared with BSHC, 135 and 194 differential metabolites were identified in BCYC and BCZC, respectively, which were mainly fatty acyls, organooxygen metabolites. A total of 163 differential metabolites were obtained between BCYC and BCZC, including phenolic acids and lipids. Compared with BSHC, 6557 and 5621 differential expression genes (DEGs) were found in BCYC and BSHC, respectively, which were annotated into biosynthesis of unsaturated fatty acid and fatty acid metabolism. A total of 4,880 DEGs existed between the two cultivars of B. chinense. The abundance of flavonoids in B. scorzonerifolium was higher than that of B. chinense, with the latter having higher saikosaponin A and saikosaponin D than the former. Pinobanksin was the most major flavonoid which differ between the two cultivars of B. chinense. The expression of chalcone synthase gene was dramatically differential, which had a positive correlation with the biosynthesis of pinobanksin. The present study laid a foundation for further research on biosynthesis of flavonoids and terpenoids of Bupleurum L.


Assuntos
Medicamentos de Ervas Chinesas , Saponinas , Transcriptoma , Metabolômica , Flavonoides , Raízes de Plantas/genética , Saponinas/genética
13.
Environ Pollut ; 307: 119550, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35636718

RESUMO

Indoor semi-volatile organic compounds (SVOCs) can have a significant impact on human health. Previous studies involved the detection of limited classes of indoor SVOCs in different regions of China. However, overall indoor pollution profiles and the associated health risks via multiple exposure pathways remain unclear. High-throughput screening of SVOCs would help clarify the overall indoor pollution status and identify high-risk pollutants. We collected indoor air and dust samples from 35 Chinese homes and investigated the occurrence of a wide range of SVOCs. Ninety-seven SVOCs including phthalate esters (PAEs), polycyclic aromatic hydrocarbons (PAHs), organophosphate esters, alcohols, fatty acids, phenols, etc., were detected in the air (total concentrations: 0.13-48 µg/m3; median: 3.4 µg/m3) and dust (total concentrations: 120-1500 µg/g; median: 490 µg/g) samples. PAEs were the most abundant, accounting for 55.3 ± 28.6% and 43.4 ± 16.9% of the total SVOC concentrations in the air and dust samples respectively. Human exposure and health risks of 34 SVOCs with detection frequencies >10% were assessed based on inhalation, ingestion and dermal absorption of SVOCs from air and dust by infants and adults. In the case of indoor SVOCs with log Koa < 9, inhalation and dermal contact with air was >90% for adults and >69% for infants. The following five SVOCs in air samples posed significant non-carcinogenic risks and are listed based on their decreasing risk level: dibutyl phthalate > phenanthrene > stearic acid > methyl palmitate > lauryl alcohol. Four PAHs with 2-4 rings posed potential carcinogenic risks, with phenanthrene exceeding the acceptable risk level of 10-4. The high risks posed by SVOCs were due to inhalation exposure. Therefore, keeping the air concentrations of SVOCs, especially that of PAEs and PAHs under check would greatly benefit human health in indoor environments.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Fenantrenos , Hidrocarbonetos Policíclicos Aromáticos , Compostos Orgânicos Voláteis , Adulto , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Poeira/análise , Ésteres , Humanos , Lactente , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de Risco , Compostos Orgânicos Voláteis/análise
14.
FEBS Open Bio ; 12(7): 1344-1352, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35429231

RESUMO

Chaihu, the dried roots of some species of Bupleurum L., is a famous Chinese herbal medicine for treatment of liver- and cold-related diseases, in which saikosaponins (SSs) are the major active compounds. Many of the genetic components upstream of SS biosynthetic pathways have been characterized; however, the regulatory mechanisms remain elusive. In this study we identified the APETALA2/Ethylene Responsive Factor family transcription factor gene BcERF3 from B. chinense. The expression of BcERF3 was induced in methyl-jasmonate-treated adventitious root of B. chinense; it was also expressed at higher levels in roots than in other tissues (stem, leaf, flower, and tender fruit of early fruiting plants). Transient expression of BcERF3 in the leaves of Nicotiana benthamiana resulted in intracellular localization of the protein in the nucleus. It was also demonstrated that the number of SSs was greater in BcERF3-overexpressing hairy roots of B. chinense than in plants treated with empty vector controls. This coincided with upregulation of ß-AS, which encodes a key enzyme involved with triterpenoid biosynthesis. In conclusion, BcERF3 plays a positive regulatory role in the biosynthesis of SSs.


Assuntos
Bupleurum , Ácido Oleanólico , Bupleurum/genética , Bupleurum/metabolismo , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/metabolismo , Raízes de Plantas/genética , Saponinas
15.
Curr Pharm Biotechnol ; 23(14): 1678-1690, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35255784

RESUMO

BACKGROUND: Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 technology is widely used in disease treatment and medicinal plant improvements due to its advantages, such as easy operation, low time consumption, and high efficiency. However, potential off-target risks still exist in practical applications and need to be solved urgently. OBJECTIVES: This study aimed to review the application progress of CRISPR/Cas9 technology in the field of disease treatment and medicinal agriculture in recent years. Furthermore, the study discusses the ways to reduce the off-target effect of CRISPR/Cas9 technology, providing a reference for the further application of this technology. METHODS: CiteSpace software was used to analyze relevant literature data from 2013 to August 2021, and search results were retrieved from Web of Science, PubMed, and CNKI databases. RESULTS: In the field of disease treatment, CRISPR/Cas9 technology has great potential to cure challenging human diseases and has been widely used in drug target development, drug design, and screening. In crop breeding, CRISPR/Cas9 accelerates the improvement of crop varieties and shortens the number of years of crop breeding. By adjusting the length and GC content of sgRNA and changing the concentration of Cas9/sgRNA complex to reduce the off-target effect of CRISPR/Cas9 technology, the target genes can be manipulated more accurately. CONCLUSION: CRISPR/Cas9 technology is an indispensable and key technology in the field of disease treatment and medicinal plants. With the in-depth study of the off-target effect, CRISPR/Cas9 technology can have broader application prospects in the fields of medicine and medicinal agriculture.


Assuntos
Edição de Genes , Plantas Medicinais , Humanos , Sistemas CRISPR-Cas , Edição de Genes/métodos , Plantas Medicinais/genética
16.
Artigo em Inglês | MEDLINE | ID: mdl-35055615

RESUMO

Cadmium is a toxic element with a half-life of several decades, which can accumulate in the human body by entering the food chain and seriously harm health. The cadmium adsorption and desorption processes in the soil directly affect the migration, transformation, bioavailability, and ecotoxicity of this element in soil-plant systems. Coastal zones are located in the transitional zone between land and sea, and large amounts of terrigenous material input have important environmental effects on this ecosystem. The pH, hydrodynamic conditions, soil organic matter (SOM), and other factors defining the sea-land interaction within the sedimentary environment are significantly different from those defining land facies. In order to study the key factors affecting cadmium adsorption in soils at the sea-land interface in the Nansha area of the Pearl River Delta, a test was conducted on a column of undisturbed soil. The results showed that the adsorption constant KF and the Cd2+ adsorption capacity of marine soils were higher than those of terrestrial soils. However, the saturation adsorption of cadmium in terrestrial sediments was higher than in marine sediments. Soil pH was an important factor affecting cadmium adsorption capacity in both terrestrial and ma-rine sediments. Neutral and alkaline topsoil conditions inhibited the vertical migration of cadmium, while the acidic environment favored it. The higher the clay and SOM were, the stronger the Cd2+ adsorption capacity of the soil was. These findings suggest that the distribution of cadmium in marine and continental sedimentary soils is not only related to adsorption, but also to the physical and chemical processes occurring in different sedimentary environments.


Assuntos
Poluentes do Solo , Solo , Adsorção , Cádmio/análise , Ecossistema , Monitoramento Ambiental , Humanos , Concentração de Íons de Hidrogênio , Rios , Poluentes do Solo/análise
18.
J Hazard Mater ; 422: 126848, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34403943

RESUMO

Face masks are necessary for fighting against the coronavirus disease 2019 around the world. As the face mask is usually made from polymers and phthalates are widely-used additives into the polymers, the face mask could be a potential source of phthalate exposure to humans. However, limited knowledge is available on the occurrence and risks of the phthalates from the face mask. In this study, twelve phthalates were determined in 56 mask samples collected from different countries. The phthalates were detected in all the samples with total levels ranging from 115 ng/g to 37,700 ng/g. Estimated daily intakes (EDIs) of the phthalates from the masks ranged from 3.71 to 639 ng/kg-bw/day, and the EDIs of the phthalates from masks for toddlers were approximately 4-5 times higher than those for adults. Non-carcinogenic risks in relation to the phthalates in masks were found to be within safe levels, yet 89.3% of the mask samples exhibited potential carcinogenic effects to humans. The extent of the risks for wearing masks located at a moderate level comparing with other skin-contacted products. This study unveiled a potential source of phthalate exposure to human, and indicated necessity of managing types and levels of additives in the face masks.


Assuntos
COVID-19 , Ácidos Ftálicos , Adulto , Humanos , Máscaras , Ácidos Ftálicos/toxicidade , SARS-CoV-2
19.
Environ Sci Technol ; 55(17): 11874-11884, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34488350

RESUMO

Benzotriazole ultraviolet stabilizers (BUVSs) are high-production-volume chemicals with ubiquitous occurrence in the aquatic environment. However, little is known about their bioconcentration and biotransformation, and physiologically based toxicokinetic (PBTK) models for BUVSs are lacking. This study selected six BUVSs for which experiments were performed with zebrafish (Danio rerio) exposed to two different levels (0.5 and 10 µg·L-1). Higher kinetic bioconcentration factors (BCFs) were observed at the lower exposure level with environmental relevance, with BCF of 3.33 × 103 L·kg-1 for 2-(2-hydroxy-3,5-di-tert-butylphenyl)-5-chlorobenzotriazole (UV-327). This phenomenon was interpreted by a nonlinear adsorption mechanism, where binding with specific protein sites contributes to bioconcentration. Muscle exhibited the lowest accumulation, in which depuration half-life of UV-327 was 19.5 d. In kidney, muscle, ovary, gill, and skin, logBCF increased with increase in log KOW of the BUVSs until log KOW was ca. 6.5, above which logBCF decreased. However, the trend was not observed in the liver and intestine. Six biotransformation products were identified and mainly accumulated in the liver and intestine. Considering the nonlinear adsorption mechanism in the PBTK model, the prediction accuracy of the model was improved, highlighting the binding of xenobiotics with specific protein sites in assessing the bioconcentration of chemicals for their risk assessment.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Biotransformação , Feminino , Toxicocinética , Triazóis , Raios Ultravioleta
20.
G3 (Bethesda) ; 11(5)2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33755111

RESUMO

MicroRNAs (miRNAs), a class of 22 nucleotide (nt) noncoding RNAs, negatively regulate mRNA posttranscriptional modification in various biological processes. Morphogenesis of skin hair follicles in cashmere goats is a dynamic process involving many key signaling molecules, but the associated cellular biological mechanisms induced by these key signaling molecules have not been reported. In this study, differential expression, bioinformatics, and Gene Ontology/Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed on miRNA expression profiles of Inner Mongolian cashmere goats at 45, 55, and 65 days during the fetal period, and chi-miR-370-3p was identified and investigated further. Real-time fluorescence quantification (qRT-PCR), dual luciferase reporting, and Western blotting results showed that transforming growth factor beta receptor 2 (TGF-ßR2) and fibroblast growth factor receptor 2 (FGFR2) were the target genes of chi-miR-370-3p. Chi-miR-370-3p also regulated the expression of TGF-ßR2 and FGFR2 at mRNA and protein levels in epithelial cells and dermal fibroblasts. DNA staining, Cell Counting Kit-8, and fluorescein-labelled Annexin V results showed that chi-miR-370-3p inhibited the proliferation of epithelial cells and fibroblasts but had no effect on apoptosis. Cell scratch test results showed that chi-miR-370-3p promoted the migration of epithelial cells and fibroblasts. Chi-miR-370-3p inhibits the proliferation of epithelial cells and fibroblasts by targeting TGF-ßR2 and FGFR2, thereby improving cell migration ability and ultimately regulating the fate of epithelial cells and dermal fibroblasts to develop the placode and dermal condensate, inducing hair follicle morphogenesis.


Assuntos
Cabras , MicroRNAs , Animais , Proliferação de Células , Perfilação da Expressão Gênica , Cabras/genética , Folículo Piloso , MicroRNAs/genética , Morfogênese
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